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Richard S. Boardman was an American paleontologist and curator of the Department of Paleobiology at the United States National Museum (now the National Museum of Natural History). Boardman worked for the museum from 1957 to 1985 and subsequently became a founding member of the International Bryozoology Association (IBA). Boardman is best known for the hard/soft thin-sectioning technique that he developed in order to compare the internal morphology of living and fossilized bryozoans which have revealed new information about bryozoan life history. | Natural_sciences | https://en.wikipedia.org/wiki?curid=35760811 | Richard S. Boardman |
Mackenzie Gordon Jr. (1913–1992) was an American invertebrate paleontologist. He was an expert on Carboniferous fossils. Gordon worked for the United States Geological Survey for 40 years, from 1941–1981. He was a research associate at the National Museum of Natural History from 1981 to his death in 1992. | Natural_sciences | https://en.wikipedia.org/wiki?curid=35760852 | Mackenzie Gordon Jr. |
Janez Matjašič (14 May 1921 – 9 August 1996) was a Slovene zoologist. Matjašič was an associate member of the Slovenian Academy of Sciences and Arts from 1974 and a full member from 1989. Apart from scientific contributions he also wrote two popular science books "Nevidno življenje" (Invisible Life) and "Iz življenja najmanjših" (From the Lives of the Smallest). For the latter he won the Levstik Award in 1956. | Natural_sciences | https://en.wikipedia.org/wiki?curid=35764931 | Janez Matjašič |
Bates–Guggenheim Convention In chemistry, the refers to a conventional method based on the Debye–Hückel theory to determine pH standard values. | Natural_sciences | https://en.wikipedia.org/wiki?curid=35769512 | Bates–Guggenheim Convention |
Vincent Moncrief Vincent Edward Moncrief is an American mathematician and physicist at Yale University. He works in relativity and mathematical physics. Moncrief earned his doctorate in 1972 at the University of Maryland College Park under the supervision of Charles William Misner and worked subsequently at the University of California Berkeley and at the University of Utah. He grew up in Oklahoma City. A key result (obtained jointly with Arthur Fischer of the University of California at Santa Cruz) was to relate the reduced Hamiltonian for Einstein's equations to a topological invariant known as the Yamabe invariant (or sigma constant) for the spatial manifold and to show that the reduced Hamiltonian is monotonically decreasing along all solutions of the field equations (in the direction of cosmological expansion) and therefore evidently seeking to attain its infimum which in turn is expressible in terms of the sigma constant. A discussion of this and related work (with Lars Andersson of the University of Miami and Yvonne Choquet-Bruhat of the Université Paris VI) may be found in Moncrief's and Choquet-Bruhat's lectures at the Cargese summer school on 50 years of the Cauchy Problem in General Relativity. Moncrief's own research is mainly concerned with the global existence and asymptotic properties of cosmological solutions of Einstein's equations and especially the question of how these properties depend upon the topology of spacetime | Natural_sciences | https://en.wikipedia.org/wiki?curid=35783189 | Vincent Moncrief |
Vincent Moncrief He is also interested in how a study of the "Einstein flow" on various manifolds might shed light on open questions in 3-manifold topology itself. Most of this research involves the treatment of sufficiently small but nevertheless fully non-linear perturbations of certain special backgrounds and includes an analysis of higher as well as lower-dimensional spacetimes in addition to physical (3 + 1)-dimensional spacetime. | Natural_sciences | https://en.wikipedia.org/wiki?curid=35783189 | Vincent Moncrief |
Jeans's theorem In astrophysics and statistical mechanics, Jeans's theorem, named after James Jeans, states that any steady-state solution of the collisionless Boltzmann equation depends on the phase space coordinates only through integrals of motion in the given potential, and conversely any function of the integrals is a steady-state solution. is most often discussed in the context of potentials characterized by three, global integrals. In such potentials, all of the orbits are regular, i.e. non-chaotic; the Kepler potential is one example. In generic potentials, some orbits respect only one or two integrals and the corresponding motion is chaotic. can be generalized to such potentials as follows: The phase-space density of a stationary stellar system is constant within every well-connected region. A well-connected region is one that cannot be decomposed into two finite regions such that all trajectories lie, for all time, in either one or the other. Invariant tori of regular orbits are such regions, but so are the more complex parts of phase space associated with chaotic trajectories. Integrability of the motion is therefore not required for a steady state. | Natural_sciences | https://en.wikipedia.org/wiki?curid=35784363 | Jeans's theorem |
Function-spacer-lipid Kode construct Function-Spacer-Lipid (FSL) Kode constructs (Kode Technology) are amphiphatic, water dispersible biosurface engineering constructs that can be used to engineer the surface of cells, viruses and organisms, or to modify solutions and non-biological surfaces with bioactives. FSL Kode constructs spontaneously and stably incorporate into cell membranes. FSL Kode constructs with all these aforementioned features are also known as Kode Constructs. The process of modifying surfaces with FSL Kode constructs is known as "koding" and the resultant "koded" cells, viruses and liposomes are respectively known as kodecytes, and kodevirions. All living surfaces are decorated with a diverse range of complex molecules, which are key modulators of chemical communications and other functions such as protection, adhesion, infectivity, apoptosis, etc. Functional-Spacer-Lipid (FSL) Kode constructs can be synthesized to mimic the bioactive components present on biological surfaces, and then re-present them in novel ways. The architecture of an FSL Kode construct, as implicit in the name, consists of three components - a functional head group, a spacer, and a lipid tail. This structure is analogous to a Lego minifigure in that, they have three structural components, with each component having a separate purpose. In the examples shown in all the figures, a Lego 'minifig' has been used for the analogy | Natural_sciences | https://en.wikipedia.org/wiki?curid=35823031 | Function-spacer-lipid Kode construct |
Function-spacer-lipid Kode construct However, it should be appreciated that this is merely a representation and the true structural similarity is significantly varied between Lego minifigures and FSL Kode constructs "(fig 1)". The functional group of an FSL is equivalent to a Lego minifigure head, with both being at the extremity and carrying the character functional components. The spacer of the FSL is equivalent to the body of the Lego minifigure and the arms on the minifigure are representative of substitutions which may be engineered into the chemical makeup of the spacer. The lipid of the FSL anchors it to lipid membranes and gives the FSL construct its amphiphatic nature which can cause it to self-assemble. Because the lipid tail can act directly as an anchor it is analogous to the legs of a Lego minifigure. The functional group, the spacer and the lipid tail components of the FSL Kode construct can each be individually designed resulting in FSL Kode constructs with specific biological functions. The functional head group is usually the bioactive component of the construct and the various spacers and lipids influence and effect its presentation, orientation and location on a surface. Critical to the definition of an FSL Kode construct is the requirement to be dispersible in water, and spontaneously and stably incorporate into cell membranes. Other lipid bioconjugates that include components similar to FSLs but do not have these features are not termed as Function-Spacer-Lipid Kode constructs | Natural_sciences | https://en.wikipedia.org/wiki?curid=35823031 | Function-spacer-lipid Kode construct |
Function-spacer-lipid Kode construct A large range of functional groups have already been made into FSL Kode constructs. These include: "Note 1: Multimeric – the presentation of the F residue can be as multimers with controlled spacing and be variable." "Note 2: Mass – the mass that can be anchored by an FSL Kode constructs can range from 200 to >1x10 Da" The spacer is an integral part of the FSL Kode construct and gives it several important characteristics including water dispersibility. The lipid tail is essential for enabling lipid membrane insertion and retention but also for giving the construct amphiphilic characteristics that enable hydrophilic surface coating (due to formation of bilipid layers). Different membrane lipids that can be used to create FSLs have different membrane physiochemical characteristics and thus can affect biological function of the FSL. Lipids in FSL Kode constructs include: One of the important functions of an FSL construct is that it can optimise the presentation of antigens, both on cell surfaces and solid-phase membranes. This optimisation is achieved primarily by the spacer, and secondarily by the lipid tail. In a typical immunoassay, the antigen is deposited directly onto the microplate surface and binds to the surface either in a random fashion, or in a preferred orientation depending on the residues present on the surface of this antigen. Usually this deposition process is uncontrolled | Natural_sciences | https://en.wikipedia.org/wiki?curid=35823031 | Function-spacer-lipid Kode construct |
Function-spacer-lipid Kode construct In contrast, the FSL Kode construct bound to a microplate presents the antigen away from the surface in an orientation with a high level of exposure to the environment. Furthermore, typical immunoassays use recombinant peptides rather than discrete peptide antigens. As the recombinant peptide is many times bigger than the epitope of interest, a lot of undesired and unwanted peptide sequences are also represented on the microplate. These additional sequences may include unwanted microbial related sequences (as determined by a BLAST analysis) that can cause issues of low level cross-reactivity. Often the mechanism by which an immunoassay is able to overcome this low level activity is to dilute the serum so that the low level microbial reactive antibodies are not seen, and only high-level specific antibodies result in an interpretable result. In contrast, FSL Kode constructs usually use specifically selected peptide fragments (up to 40 amino acids), thereby overcoming cross-reactivity with microbial sequences, and allowing for the use of undiluted serum (which increases sensitivity). The F component can be further enhanced by presentation of it in multimeric formats and with specific spacing. The four types of multimeric format include linear repeating units, linear repeating units with spacing, clusters, and branching "(Fig. 4)". The FSL Kode construct by nature of its composition in possessing both hydrophobic and hydrophilic regions are amphiphilic (or amphipathic) | Natural_sciences | https://en.wikipedia.org/wiki?curid=35823031 | Function-spacer-lipid Kode construct |
Function-spacer-lipid Kode construct This characteristic determines the way in which the construct will interact with surfaces. When present in a solution they may form simple micelles or adopt more complex bilayer structures with two simplistic examples shown in "Fig. 5a". More complex structures are expected. The actual nature of FSL micelles has not been determined. However, based on normal structural function of micelles, it is expected that it will be determined in part by the combination of functional group, spacer and lipid together with temperature, concentration, size and hydrophobicity/hydrophilicity for each FSL Kode construct type. Surface coatings will occur via two theoretical mechanisms, the first being direct hydrophobic interaction of the lipid tail with a hydrophobic surface resulting in a monolayer of FSL at the surface "(Fig. 5b)". Hydrophobic binding of the FSL will be via its hydrophobic lipid tail interacting directly with the hydrophobic (lipophilic) surface. The second surface coating will be through the formation of bilayers as the lipid tail is unable to react with the hydrophilic surface. In this case the lipids will induce the formation of a bilayer, the surface of which will be hydrophilic. This hydrophilic membrane will then interact directly with the hydrophilic surface and will probably encapsulate fibres. This hydrophilic bilayer binding is the expected mechanism by which FSLs are able to bind to fibrous membranes such as paper and glass fibres "(Fig. 5c)" and "(Fig. 9)" | Natural_sciences | https://en.wikipedia.org/wiki?curid=35823031 | Function-spacer-lipid Kode construct |
Function-spacer-lipid Kode construct After labeling of the surface with the selected F bioactive(s) the constructs will be present and orientated at the membrane surface. It is expected that the FSL will be highly mobile within the membrane and the choice of lipid tail will effect is relative partitioning within the membrane. The construct unless it has flip-flop behavior is expected to remain surface presented. However, the modification is not permanent in living cells and constructs will be lost (consumed) at a rate proportional to the activity at the membrane and division rate of the cell (with dead cells remaining highly labeled). Additionally, when present "in vivo" with serum lipids FSLs will elute from the membrane into the plasma at a rate of about 1% per hour. In fixed cells or inactive cells (e.g. red cells) stored in serum free media the constructs are retained normally. Liposomes are easy koded by simply adding FSL Kode constructs into the preparation. Contacting koded liposomes with microplates or other surfaces can cause the labeling of the microplate surface. Non-biologic surface coatings will occur via two mechanisms, the first being direct hydrophobic interaction of the lipid tail with a hydrophobic surface resulting in a monolayer of FSL at the surface. The second surface coating will be through the formation of bilayers, which probably either encapsulate fibres or being via the hydrophilic F group. This is the expected mechanism by which FSLs bind to fibrous membranes such as paper and glass fibres | Natural_sciences | https://en.wikipedia.org/wiki?curid=35823031 | Function-spacer-lipid Kode construct |
Function-spacer-lipid Kode construct A recent study has found that when FSL Kode constructs are optimised, could in a few seconds glycosylate almost any non-biological surface including metals, glass, plastics, rubbers, and other polymers. The technological features of FSL Kode constructs and the koding process can be summarized as follows: FSL constructs have a wide range of uses and they have been used to modify the following: FSL constructs, when in solution (saline) and in contact, will spontaneously incorporate into cell and virus membranes. The methodology involves simply preparing a solution of FSL construct(s) in the range of 1–1000 μg/mL. The actual concentration will depend on the construct and the quantity of construct required in the membrane. One part of FSL solution is added to one part of cells (up to 100% suspension) and they are incubated at a set temperature within the range of 4–37 °C (39–99 °F) depending on temperature compatibility of the cells being modified. The higher the temperature, the faster the rate of FSL insertion into the membrane. For red blood cells, at 37 °C incubation for 2 hours achieves >95% insertion with at least 50% insertion being achieved within 20 minutes. In general, FSL insertion time of 4 hours at room temperature or 20 hours at 4 °C gives results similar to 1 hour at 37 °C for carbohydrate based FSLs inserting into red blood cells. The resultant kodecytes or kodevirions do not required to be washed, however this option should be considered if an excess of FSL construct is used in the koding process | Natural_sciences | https://en.wikipedia.org/wiki?curid=35823031 | Function-spacer-lipid Kode construct |
Function-spacer-lipid Kode construct FSL Kode constructs have been used for research and development, diagnostic products, and are currently being investigated as potential therapeutic agents. FSL have been used to create human red cell kodecytes that have been used to detect and identify blood group allo-antibodies as ABO sub-group mimics, ABO quality control systems, serologic teaching kits and a syphilis diagnostic. Kodecytes have also demonstrated that FSL-FLRO4 is a suitable reagent for labelling packed red blood cells (PRBC) at any point during routine storage and look to facilitate the development of immunoassays and transfusion models focused on addressing the mechanisms involved in tansfusion-related immunomodulation (TRIM). Murine kodecytes have been experimentally used to determine "in vivo" cell survival, and create model transfusion reactions. Zebrafish kodecytes have been used to determine real time "in vivo" cell migration. Kodecytes have been used to create influenza diagnostics. Kodecytes which have been modified with FSL-GB3 were unable to be infected with the HIV virus. Kodevirions are FSL modified viruses. Several FSL Kode constructs have been used to label viruses to assist in their flow-cytometric visualisation and to track them real time distribution in animal models. They have also been used to modify the surface of viruses with the intention of targeting them to be used to attach tumors (oncolytic). Kodesomes are liposomes that have been decorated with FSL Kode constructs | Natural_sciences | https://en.wikipedia.org/wiki?curid=35823031 | Function-spacer-lipid Kode construct |
Function-spacer-lipid Kode construct These have been used to deposit FSL constructs onto microplates to create diagnostic assays. They also have the potential for therapeutic use. These are solutions containing FSL Kode constructs where the construct will exist as a clear micellular dispersion. FSL-GB3 as a solution/gel has been used to inhibit HIV infection and to neutralise Shiga toxin. FSL blood group A as a solution has been used to neutralise circulating antibodies in a mouse model and allow incompatible blood group A (murine kodecytes) transfusion. This model experiment was used to demonstrate the potential of FSLs to neutralise circulating antibody and allow for incompatible blood transfusion or organ transplantation. All FSL Kode constructs disperse in water and are therefore compatible with inkjet printers. FSL constructs can be printed with a standard desktop inkjet printer directly onto paper to create immunoassays. An empty ink cartridge is filled with an FSL construct and words, barcodes, or graphics are printed. A Perspex template is adhered to the surface to create reaction wells. The method is then a standard EIA procedure, but blocking of serum is not required and undiluted serum can be used. A typical procedure is as follows: add serum, incubate, wash by immersion, add secondary EIA conjugate, incubate, wash, add NBT/BCIP precipitating substrate and stop the reaction when developed by washing "(Fig. 9)". The end result is stable for years. | Natural_sciences | https://en.wikipedia.org/wiki?curid=35823031 | Function-spacer-lipid Kode construct |
Fourmarierite is a secondary uranium-lead mineral. It was named for the Belgian geologist Paul Fourmarier (1877–1970). Its chemical formula is Pb(UO)O(OH)•4HO. | Natural_sciences | https://en.wikipedia.org/wiki?curid=35828084 | Fourmarierite |
Angelo Andres Angelo "Ginobili" Andres (24 March 1851, Tirano –16 July 1934, Milan) was an Italian zoologist. Dr. studied natural history in Pavia, Leipzig, London and Paris. He became a Professor in Moderna. From 1899–1926 he was director of Museo di Storia Naturale in Parma. He was a friend of Anton Dohrn. Andres was a supporter of Darwinism and gave anniversary lectures supporting his ideas. | Natural_sciences | https://en.wikipedia.org/wiki?curid=35828206 | Angelo Andres |
Sulfido refers to the ligand species S. There is only one donor atom present in this ligand which is sulfur. | Natural_sciences | https://en.wikipedia.org/wiki?curid=35828754 | Sulfido |
WISE J004945.61+215120.0 is a brown dwarf of spectral class T8.5, located in constellation Andromeda at approximately 24 light-years from Earth. was discovered in 2012 by Mace et al. from data, collected by Wide-field Infrared Survey Explorer (WISE) Earth-orbiting satellite — NASA infrared-wavelength 40 cm (16 in) space telescope, which mission lasted from December 2009 to February 2011. In 2013, the discovery paper was published. Trigonometric parallax of is not yet measured. Therefore, there are only distance estimates of this object, obtained by indirect — spectrofotometric — means (see table). distance estimates | Natural_sciences | https://en.wikipedia.org/wiki?curid=35835795 | WISE J004945.61+215120.0 |
WISE J031624.35+430709.1 is a brown dwarf of spectral class T8, located in constellation Perseus at approximately 106 light-years from Earth. It is one of the furthest T-class brown dwarfs known. was discovered in 2012 by Mace et al. from data, collected by Wide-field Infrared Survey Explorer (WISE) Earth-orbiting satellite — NASA infrared-wavelength 40 cm (16 in) space telescope, which mission lasted from December 2009 to February 2011. In March 2013, the discovery paper was published. Trigonometric parallax of is not yet measured. Therefore, there are only distance estimates of this object, obtained by indirect — spectrofotometric — means (see table). distance estimates | Natural_sciences | https://en.wikipedia.org/wiki?curid=35835799 | WISE J031624.35+430709.1 |
WISE J0005+3737 WISE J0005+3737, full designation WISE J000517.48+373720.5, is a brown dwarf of spectral class T9, located in constellation Andromeda at approximately 23 light-years from Earth. was discovered in 2012 by Mace et al. from data, collected by Wide-field Infrared Survey Explorer (WISE) Earth-orbiting satellite — NASA infrared-wavelength 40 cm (16 in) space telescope, which mission lasted from December 2009 to February 2011. The discovery paper was published in March 2013. Trigonometric parallax of is not yet measured. Therefore, there are only distance estimates of this object, obtained by indirect — spectrophotometric — means (see table). distance estimates | Natural_sciences | https://en.wikipedia.org/wiki?curid=35835864 | WISE J0005+3737 |
WISE 0146+4234 WISE J014656.66+423410.0 (designation abbreviated to WISE 0146+4234) is a binary brown dwarf of spectral classes T9 and Y0 located in the constellation Andromeda. It is approximately 60 light-years from Earth.. was discovered in 2012 by J. Davy Kirkpatrick et al. from data, collected by Wide-field Infrared Survey Explorer (WISE) Earth-orbiting satellite — NASA infrared-wavelength 40 cm (16 in) space telescope, which mission lasted from December 2009 to February 2011. In 2012 Kirkpatrick et al. published a paper in The Astrophysical Journal, where they presented discovery of seven new found by WISE brown dwarfs of spectral type Y, among which also was WISE 0146+4234. The distance of was initially estimated to be 20 light-years from earth. Later measurements of its stellar parallax showed that it was actually 60 light-years away. The other six discoveries of brown dwarfs, published in Kirkpatrick et al. (2012): | Natural_sciences | https://en.wikipedia.org/wiki?curid=35835908 | WISE 0146+4234 |
WISE 0359−5401 WISE J035934.06−540154.6 (designation abbreviated to WISE 0359−5401) is a brown dwarf of spectral class Y0, located in constellation Reticulum. Estimated to be approximately 22.5 light-years from Earth, it is one of the Sun's nearest neighbors. was discovered in 2012 by J. Davy Kirkpatrick and colleagues from data collected by the Wide-field Infrared Survey Explorer (WISE) in the infrared at a wavelength of 40 cm (16 in), whose mission lasted from December 2009 to February 2011. In 2012 Kirkpatrick et al. published a paper in The Astrophysical Journal, where they presented discovery of seven new found by WISE brown dwarfs of spectral type Y, among which also was WISE 0359−5401. The trigonometric parallax of is arcsec, corresponding to a direct inversion distance of , or . The other six discoveries of brown dwarfs, published in "Kirkpatrick et al. (2012)": | Natural_sciences | https://en.wikipedia.org/wiki?curid=35835912 | WISE 0359−5401 |
WISE 0713−2917 WISE J071322.55−291751.9 (designation abbreviated to WISE 0713−2917) is a brown dwarf of spectral class Y0, located in constellation Canis Major at approximately 23 light-years from Earth. was discovered in 2012 by J. Davy Kirkpatrick and colleagues from data collected by the Wide-field Infrared Survey Explorer (WISE) in the infrared at a wavelength of 40 cm (16 in), whose mission lasted from December 2009 to February 2011. In 2012 Kirkpatrick et al. published a paper in The Astrophysical Journal, where they presented discovery of seven new found by WISE brown dwarfs of spectral type Y, among which also was WISE 0713−2917. Trigonometric parallax of is not yet measured. Therefore, there are only distance estimates of this object, obtained by indirect—spectrophotometric—means (see table). distance estimates The other six discoveries of brown dwarfs, published in Kirkpatrick et al. (2012): | Natural_sciences | https://en.wikipedia.org/wiki?curid=35835955 | WISE 0713−2917 |
WISE 0734−7157 WISE J073444.02−715744.0 (designation abbreviated to WISE 0734−7157) is a brown dwarf of spectral class Y0, located in constellation Volans at approximately 35 light-years from Earth. It is one of the furthest Y0 brown dwarfs known. was discovered in 2012 by J. Davy Kirkpatrick et al. from data, collected by Wide-field Infrared Survey Explorer (WISE) Earth-orbiting satellite — NASA infrared-wavelength 40 cm (16 in) space telescope, which mission lasted from December 2009 to February 2011. In 2012 Kirkpatrick et al. published a paper in The Astrophysical Journal, where they presented discovery of seven new found by WISE brown dwarfs of spectral type Y, among which also was WISE 0734−7157. Trigonometric parallax of is not yet measured. Therefore, there are only distance estimates of this object, obtained by indirect — spectrofotometric — means (see table). distance estimates The other six discoveries of brown dwarfs, published in Kirkpatrick et al. (2012): | Natural_sciences | https://en.wikipedia.org/wiki?curid=35835956 | WISE 0734−7157 |
WISE 2220−3628 WISE J222055.31−362817.4 (designation abbreviated to WISE 2220−3628) is a brown dwarf of spectral class Y0, located in constellation Grus at approximately 26 light-years from Earth. was discovered in 2012 by J. Davy Kirkpatrick et al. from data, collected by Wide-field Infrared Survey Explorer (WISE) Earth-orbiting satellite — NASA infrared-wavelength 40 cm (16 in) space telescope, which mission lasted from December 2009 to February 2011. In 2012 Kirkpatrick et al. published a paper in The Astrophysical Journal, where they presented discovery of seven new found by WISE brown dwarfs of spectral type Y, among which also was WISE 2220−3628. Y-class dwarfs are among the coldest of all brown dwarfs. Trigonometric parallax of is not yet measured. Therefore, there are only distance estimates of this object, obtained by indirect — spectrofotometric — means (see table). | Natural_sciences | https://en.wikipedia.org/wiki?curid=35835958 | WISE 2220−3628 |
Beau Sancy The is a modified "pear double rose cut" diamond found in India that has been owned by a number of European royal houses. In May 2012, it was sold at Sotheby's auction in Geneva for $9.57 million. The original estimated price of $2 million was lifted five times during the eight-minute battle between five buyers, before the diamond was sold to one of them who remained anonymous. The diamond takes its name from Nicolas de Harlay, Lord of Sancy, who brought the diamond to France from India where he had been the French ambassador. Its larger sibling diamond, the Grand Sancy, was sold to James I of England for his Queen, Henrietta Maria. The was acquired by the Queen of France, Marie de Medicis. From Marie de Medicis, it passed to the Dutch King William, later William III of England, and his wife Queen Mary II. In 1701 it passed from the Dutch royal family to Frederick I of Prussia. | Natural_sciences | https://en.wikipedia.org/wiki?curid=35839423 | Beau Sancy |
Bacteriophage PBC1 is a bacteriophage that infects the spore-forming bacterium "Bacillus cereus". Though this lytic phage is a member of "Siphoviridae", its genome sequence shows little similarity to those of other sequenced phages. | Natural_sciences | https://en.wikipedia.org/wiki?curid=35841019 | Bacteriophage PBC1 |
New York orthohantavirus or New York virus is an "Orthohantavirus". It is considered a strain of "Sin Nombre orthohantavirus". It was first isolated from a white-footed mouse ("Peromyscus leucopus") caught on an island off New York. The virus is associated with typical hantavirus pulmonary syndrome. | Natural_sciences | https://en.wikipedia.org/wiki?curid=35857252 | New York orthohantavirus |
Bayou orthohantavirus (BAYV) is a species of "Orthohantavirus" first identified in 1993 in Louisiana. indicating the virus to be widespread throughout the Southeastern United States. BAYV infection causes hantavirus pulmonary syndrome (HPS) and represents the second most common hantavirus in the United States behind the "Sin Nombre orthohantavirus". | Natural_sciences | https://en.wikipedia.org/wiki?curid=35857254 | Bayou orthohantavirus |
Nigel Morritt Wace (10 January 1929 India – 4 February 2005 Canberra, Australia) was an authority on the plant life of the four Tristan da Cunha Islands, islands he first visited in 1955 when he visited Gough Island. He was educated at Brambletye School, then Sheikh Bagh Preparatory School in Kashmir, then school in Cheltenham, followed by a period as a commissioned officer in the Royal Marines form where he was invalided out in 1947, progressing to Brasenose College, Oxford. At Brasenose Wace read Agricultural Economics, switching to Botany. His later work on Tristan da Cunha led to his PhD thesis on the vegetation of Gough Island, received from Queen's University, Belfast. Wace's periods in Tristan da Cunha started with his membership as botanist of the Gough Island Scientific Survey from 1955–56. In Australia Wace made a substantial contribution to knowledge of the Australian flora, both in settled parts and in the outback. Wace married Margaret White with whom he had a son and two daughters. Wace's family claims descent from Wace, the 12th-century Jerseyman and chronicler of the House of Normandy. He was employed by the Geography department of Adelaide University, moving later to the Australian National University at Canberra where he was initially a lecturer subsequently head of the university's department of Biogeography and Geomorphology. | Natural_sciences | https://en.wikipedia.org/wiki?curid=35871518 | Nigel Morritt Wace |
NGC 321 is a barred spiral galaxy located in the constellation Cetus. It was discovered on September 27, 1864, by the astronomer Albert Marth. It was the location of the planet Eminiar VII in the original series "" episode "A Taste of Armageddon" (where it was incorrectly identified as a star cluster). | Natural_sciences | https://en.wikipedia.org/wiki?curid=35877597 | NGC 321 |
André Léon Tonnoir (9 April 1885 – 30 January 1940), was a Belgian entomologist. Born in Brussels, Tonnoir studied engineering followed by radiology at university. He worked as a technician during World War I, and after the war had ended he worked with the entomology staff at the Royal Belgian Institute of Natural Sciences in Brussels. Tonnoir focused in the area of Diptera and worked for the museum until 1921. He was then persuaded by Robert Tillyard to visit Australia for entomology work there. Soon afterwards, he left for Nelson in New Zealand to do research for the Cawthron Institute until 1924. In the same year, he moved to Christchurch for two new roles; curator at the Canterbury Museum and lecturer at Canterbury College. In 1926, he went back to work for three years at the Cawthron Institute as part of their noxious weeds programme. He eventually went back to Australia, working in Canberra as a Senior Ecologist and Curator. In Canberra he ate a lot of ice cream, and therefore they called him the "ICE-KING". | Natural_sciences | https://en.wikipedia.org/wiki?curid=35879709 | André Léon Tonnoir |
Renkonen similarity index The (P), is a measure of dissimilarity between two communities (sites), based on relative (proportional) abundances formula_1 of individuals of composite species. It was developed by the botanist Olavi Renkonen and published in 1938. The codomain of this distance function ranges from 1 (identical proportional abundances) to 0 (no taxa shared). | Natural_sciences | https://en.wikipedia.org/wiki?curid=35898747 | Renkonen similarity index |
Biotechnology Regulatory Authority of India The (BRAI) is a proposed regulatory body in India for uses of biotechnology products including genetically modified organisms (GMOs). The institute was first suggested under the (BRAI) draft bill prepared by the Department of Biotechnology in 2008. Since then, it has undergone several revisions. The bill has faced opposition from farmer groups and anti-GMO activists. On 23 January 2003, India ratified the Cartagena Protocol which protects biodiversity from potential risks of genetically modified organisms, the products of modern biotechnology. The protocol requires setting up of a regulatory body. Currently, the Genetic Engineering Approvals Committee, a body under the Ministry of Environment and Forests (India) is responsible for approval of genetically engineered products in India. If the bill is passed, the responsibility will be taken over by the Environment Appraisal Panel, a sub-division of the BRAI. According to the bill, BRAI will have a Chairperson, two full-time members and two part-time members; all will be required to have expertise in life sciences and biotechnology in agriculture, health care, environment and general biology. The bill also proposes setting up an inter-ministerial governing body, to oversee the performance of BRAI, and a National Biotechnology Advisory Council of stakeholders to provide feedback on the use of biotechnology products and organisms in the society | Natural_sciences | https://en.wikipedia.org/wiki?curid=35911437 | Biotechnology Regulatory Authority of India |
Biotechnology Regulatory Authority of India The regulatory body will be an autonomous and statutory agency to regulate the research, transport, import, and manufacture biotechnology products and organisms. Suman Sahai, founder of the Gene Campaign, has called the bill flawed. According to her, the bill is proposing new institutes without clearly defining their powers and responsibilities. She has also stated that the bill was introduced without consulting the people who will be affected by the bill. P. M. Bhargava, founder of the Centre for Cellular and Molecular Biology, has also opposed the bill. He has called the bill unconstitutional, as agricultural policy is the domain of state governments. He pointed out that the bill proposes formation of several subdivisions and has argued that they will consist of bureaucrats with no scientific knowledge. He has accused the Department of Biotechnology, which will be involved in selection of members, as a promoter of genetic technology in India. He has pointed out that the broadly defined term "confidential commercial information" has been kept outside the purview of the Right to Information Act. He had stated that the bill uses vague wordings which would criminalize sequencing or isolation of DNA and PCR techniques, requiring approval for each usage. Thus, hindering research and education. He pointed out the bill has no provision for mandatory labelling of GM foods. He criticized giving the body power to punish parties making false or misleading statements about GM crops, calling it unprecedented | Natural_sciences | https://en.wikipedia.org/wiki?curid=35911437 | Biotechnology Regulatory Authority of India |
Biotechnology Regulatory Authority of India In September 2010, Jairam Ramesh, then Environment Minister, pointed out that the body is only deals with safety and efficacy of biotechnology products. The issue of commercialization has been left unaddressed. The decisions regarding commercialization can fall under the purview of Ministry of Environment and Forests, Ministry of Health, Ministry of Agriculture, or Department of Science and Technology. On the other hand, Association of Biotechnology Led Enterprises (ABLE) has supported the bill. J.S. Rehman, an entomologist and a former member of the Review Committee on Genetic Manipulation, has stated that most protesters associate genetic engineering with Monsanto, as a result development of Indian biotech is being hindered. | Natural_sciences | https://en.wikipedia.org/wiki?curid=35911437 | Biotechnology Regulatory Authority of India |
Bio Base Europe is an innovation and training center for the biobased economy. It is a platform that supports the development of sustainable, biobased products such as bio-chemicals, bio-plastics, bio-materials, bio-detergents, bio-energy, etc. from renewable biomass resources. Its mission is to stimulate sustainable development and economic growth by facilitating R&D and training for biobased process development. It consists of a Pilot Plant for the biobased economy located in the port of Ghent (Belgium), and a Training Center for the biobased economy in Terneuzen (Netherlands). On December 12, 2008, Europe, Flanders and the Netherlands have allocated €21 million to the Interreg IV project Bio Base Europe. is the largest Interreg project ever granted to the Dutch-Flemish border region. The founding fathers are Ghent Bio-Energy Valley and Bio Park Terneuzen. In 2009, has been awarded the Sail of Papenburg prize for best innovative project by the Association of European Border Regions (AEBR). Pilot Plant is a pilot test facility for the biobased economy, built with the aim to close the gap between scientific feasibility and industrial application. It operates from kg to ton scale. The pilot plant hosts a range of process equipment to scale up biobased processes to industrial scale. Tests done in the pilot plant enable to assess operating costs, specific strengths and weaknesses of new biobased processes before costly, large-scale investments in production plant facilities are made | Natural_sciences | https://en.wikipedia.org/wiki?curid=35911445 | Bio Base Europe |
Bio Base Europe Pilot Plant has no industrial shareholders, and operates according to the open innovation service model. Companies and research centres throughout the world that are active in the biobased economy can access these facilities for their technological developments. The processes done in the pilot plant can be divided into the following categories 1. Biorefining: Biomass fractionation and pretreatment 2. Industrial biotechnology 3. Green chemistry 4. Downstream processing In the biorefining operations, biomass can be fractionated in its various parts. These operations involve a.o. milling and pulping, dispersion, homogenizing, physical separation such as centrifugation and decantation, filtration including dead end particulate filtration and cross flow membrane filtration,… Biomass can also be pretreated prior to enzymatic hydrolysis, involving pulping and homogenisation reactions, jet cooking, acid or alcaline treatment, steam explosion, etc. White or industrial biotechnology processes involves the use of microorganisms and their enzymes in so-called fermentation processes or biocatalytic reactions. Fermentations can be performed from 1 to 15.000 litre scale and involve both batch, fed batch or continuous operations. Reactors for enzymatic reactions are present that can be used with either water of organic solvents. Green chemistry is performed in explosion proof installations such as glass-lined chemical reactors (1 - 6.000 l scale) that are suited to perform under vacuum or under pressure | Natural_sciences | https://en.wikipedia.org/wiki?curid=35911445 | Bio Base Europe |
Bio Base Europe The Pilot Plant is also equipped with filter dryers for solvent extraction of liquids and solids. Downstream processing for the recovery of pure products after biochemical or chemical conversion involves various equipment for extraction, evaporation, demineralization, ion exchange, carbon treatment, crystallization, spray drying, lyophilisation, etc. Continuous process lines can be built up by connecting unit operations with mobile positive and centrifugal pumps, heat exchangers, dosing pumps, flexible and fixed piping and instrumentation. The Training Center is an education, network and exhibition center promoting the development of a sustainable biobased economy. It offers general and company-specific training and connects closely with the market demand. The Training Center works according to the one-stop-shop concept. The training center offers companies a wide range of trainings for their process operators and technical staff. For example, a training portfolio can be used by logging into a web-based learning management system. Furthermore, specific training and a full training program for technical staff are offered and support in hiring new process operators can be obtained. In addition, the Training Center is developing dynamic process simulators which can be used for the training of operators. | Natural_sciences | https://en.wikipedia.org/wiki?curid=35911445 | Bio Base Europe |
Filamentous bacteriophage fd is a type of filamentous bacteriophage known to infect "Escherichia coli". It shares many structural and genomic similarities with Enterobacteria phage M13. Phage fd engineered to display immunogenic peptides may be useful as vaccines. | Natural_sciences | https://en.wikipedia.org/wiki?curid=35913168 | Filamentous bacteriophage fd |
Available space theory In botany, Available space theory, also known as "first available space theory", is a theory used to explain why most plants have an alternating leaf pattern on their stems. The theory states that the location of a new leaf on a stem is determined by the physical space between existing leaves. In other words, the location of a new leaf on a growing stem is directly related to the amount of space between the previous two leaves. Building on ideas first put forth by Hoffmeister in 1868, Snow and Snow hypothesized in 1947 that leaves sprouted in the first available space on the stem. | Natural_sciences | https://en.wikipedia.org/wiki?curid=35924364 | Available space theory |
Repulsion theory In botany, is a theory that is used to explain how plants regulate the distance between new budding leaves on a stem. The theory states that each leaf on a stem secretes a substance that inhibits growth of a new leaf. A new leaf will only grow a certain distance away from the previous leaf where the concentration of the substance reaches a lower level. Although no inhibitors have yet been discovered, the theory is supported by several surgical and modeling experiments. | Natural_sciences | https://en.wikipedia.org/wiki?curid=35924454 | Repulsion theory |
Frank White (botanist) Frank White (5 March 1927 – 12 September 1994) was a botanist who was an expert on African flora and curator of the herbarium at the University of Oxford. | Natural_sciences | https://en.wikipedia.org/wiki?curid=35927777 | Frank White (botanist) |
Wonderful life theory In biology, the wonderful life theory, also known as contingency theory, postulates that after hundreds of different phyla evolved during the Cambrian period, many of them subsequently became extinct, leaving the relatively few phyla that exist today. The theory was first suggested in 1989 by Stephen Jay Gould in his book "Wonderful Life". In Wonderful Life, Stephen Jay Gould discusses the iconography of evolution in popular culture and the damaging effects of the march of progress on public understanding of the theory. The march of progress, Gould argues, has led to the popular interpretation that the evolution of increased mental powers, ultimately culminating in the development of man’s complex brain, is the natural outcome of evolution. Thus, the term “Evolution” is often conflated with a linear progression of life towards ever-increasing mental powers and a “comfortable view of human inevitability and superiority.” Gould argues that the definition of Evolution to professional biologists is “adaptation to changing environments”, not progress, and that the composition of life on the planet is rather a “copiously branching bush, continually pruned by the grim reaper of extinction, not a ladder of predictable progress.” In an error that Gould refers to as “life’s little joke”, he discusses society’s obsession with unsuccessful lineages as “textbook cases” of “evolution”. To elaborate, we consistently seek out “a single line of advance from the true topology of copious branching | Natural_sciences | https://en.wikipedia.org/wiki?curid=35936877 | Wonderful life theory |
Wonderful life theory In this misguided effort, we are inevitably drawn to branches so near the brink of total annihilation that they retain only one surviving twig. We then view this twig as the acme of upward achievement, rather than the probable last grasp of a richer ancestry.” Gould uses the evolution of the horse to illustrate this point, as the unbroken connection between "Hyracotherium" (formerly called "Eohippus") and "Equus" provides an apparent linear path from simplicity to complexity. The only reason the evolution of horses has become the canonical representation of progressive evolution is because their bush has been extremely unsuccessful. Instead, Gould argues, we should look to bats, antelopes, and rodents as champions of mammalian evolution as they present us with “thousands of twigs on a vigorous bush” and are the true embodiments of evolutionarily successful groups. Gould argues that the conventional view of evolution, as illustrated by the cone of increasing diversity, is flawed. It is typically assumed that early life is restricted in form, and from this restriction of form follows diversification into the variety of animal life that currently exists. This cone can be visualized as an inverted Christmas tree, with a narrow base and numerous branches proliferating outward into the present day | Natural_sciences | https://en.wikipedia.org/wiki?curid=35936877 | Wonderful life theory |
Wonderful life theory Gould presents an alternative hypothesis, however, which states that the history of life is better described as “decimation followed by diversification within a few remaining stocks”, represented as a pyramid with a wide base of anatomical disparity that becomes increasingly constrained by natural selection and extinction level events as time moves forward. This is evidenced by the fact that the fossils excavated from the Burgess Shale in British Columbia represent a paleo-ecosystem with much greater anatomical disparity than currently exists and that fewer phyla exist today compared to the Cambrian seas. Gould offers the view that life during the Cambrian explosion quickly proliferated into the diversity of forms seen today due to the availability of numerous ecological niches and was subsequently decimated by extinction level events throughout geological time. He also notes that the survival of groups following extinction events bears no relationship to traditional notions of Darwinian success in normal times. For example, Ultimately, Gould explains, both the false iconography of the march of progress and our allegiance to the cone of increasing diversity have led us astray in our thinking about trends in evolutionary biology | Natural_sciences | https://en.wikipedia.org/wiki?curid=35936877 | Wonderful life theory |
Wonderful life theory The central question proposed by Wonderful Life is that if life initially proliferated into a greater variety of phyla than currently exist and were subsequently decimated by the stochastic grim reaper of extinction, what then can be said about the inevitability of human intelligence and superiority? Additionally, Gould asks what role historical contingencies play in the evolution of life on Earth. It is these central ideas which prompt Gould to propose a thought experiment called “replaying the tape of life.” Its central essence is this: if we rewind the clock and replay the history of life on Earth numerous times, will we consistently see the same outcome that is the reality we experience today? The outcome of this thought experiment has two possible interpretations, elaborated by Gould, Gould’s opinion, and the central argument of Wonderful Life, is that “any replay of the tape of life would lead evolution down a pathway radically different from the road actually taken.” Additionally, Gould argues, no outcome can be predicated from the start, but the resulting pattern that emerges after replaying the tape of life would be just as interpretable and logical as our current situation. | Natural_sciences | https://en.wikipedia.org/wiki?curid=35936877 | Wonderful life theory |
Biological dark matter is an informal term for unclassified or poorly understood genetic material. This genetic material may refer to genetic material produced by unclassified microorganisms. By extension, biological dark matter may also refer to the un-isolated microorganism whose existence can only be inferred from the genetic material that they produce. Some of the genetic material may not fall under the three existing domains of life: Bacteria, Archaea and Eukaryota; thus, it has been suggested that a possible fourth domain of life may yet to be discovered, although other explanations are also probable. Alternatively, the genetic material may refer to non-coding DNA (so-called "junk DNA") and non-coding RNA produced by known organisms. Much of the genomic dark matter is thought to originate from ancient transposable elements and from other low-complexity repetitive elements. Uncategorized genetic material is found in humans and in several other organisms. Their phylogenetic novelty could indicate the cellular organisms or viruses from which they evolved. Up to 99% of all living microorganisms cannot be cultured, so few functional insights exist about the metabolic potential of these organisms. Sequences that are believed to be derived from unknown microbes are referred to as the ‘Microbial Dark Matter, the ‘Dark Virome’, or ‘Dark Matter Fungi’ Such sequences are not rare. It has been estimated that in material from humans, between 40 and 90% of viral sequences are from Dark Matter | Natural_sciences | https://en.wikipedia.org/wiki?curid=35942883 | Biological dark matter |
Biological dark matter Human blood contains over three thousand different DNA sequences which can not be identified. Algorithms have been developed that examine sequences for similarities to bacterial 16S RNA sequences, K-mer similarities to known viruses, specific features of codon usage, or for inferring the existence of proteins. These approaches have suggested, for example, the existence of a novel bacteriophage of the microviridae family, and a novel bacterioidales-like phage. Other studies have suggested the existence of 264 new viral genera, discovered in publicly available databases, and a study of human blood suggested that 42% of people have at least one previously unknown virus each, adding up to 19 different new genera. A comprehensive study of DNA sequences from multiple human samples inferred the existence of 4,930 species of microbes of which 77% were previously unreported. Health-related findings include a prophage that might be associated with cirrhosis of the liver, and seven novel sequences from children with type-1 diabetes that have characteristics of viruses. Although they might exist, no organisms that clearly cause human disease have been discovered in the Dark Matter. | Natural_sciences | https://en.wikipedia.org/wiki?curid=35942883 | Biological dark matter |
LiquiGlide is a platform technology which creates slippery, liquid-impregnated surfaces that was developed at the Varanasi Research Group at Massachusetts Institute of Technology by Prof. Kripa Varanasi and his team of students and post doctorals Dave Smith, Rajeev Dhiman, Adam Paxson, Brian Solomon, and Chris Love. Possible applications include improving the flow rate of condiment bottles to avoid food waste, and preventing clogs in gas and oil tubes. The inventors released videos of being used in ketchup, mayonnaise, jelly, and mustard bottles made of both plastic and glass. The project came in second place in the Business Plan Contest and won the Audience Choice Award at the 2012 MIT $100K Entrepreneurship Competition. The company has also raised $25M from investors including Roadmap Capital, Structure Capital, Valia Investments, and Struck Capital. In March 2015, signed a deal with Elmer's Products, the first company to use the technology. | Natural_sciences | https://en.wikipedia.org/wiki?curid=35943373 | LiquiGlide |
Pekka Pyykkö Veli (born October 12, 1941) is a Finnish academic. He is professor of Chemistry at the University of Helsinki. From 2009–2012, he was the chairman of the International Academy of Quantum Molecular Science. He is known for his extension to the periodic table of elements, known as the Pyykkö model. predicts that the orbital shells will fill up in this order: He also suggests that period 8 be split into three parts: The compact version:<br> successfully predicted the possibility of a chemical bond between gold and the noble gas xenon, which is usually inert; this bond is known to occur in the cationic complex tetraxenonogold(II) (). He also successfully predicted the possibility of a gold–carbon triple bond. | Natural_sciences | https://en.wikipedia.org/wiki?curid=35962306 | Pekka Pyykkö |
Robert Sharp (crater) Robert Sharp is a crater on the planet Mars in the northeastern part of Mare Tyrrhenum quadrangle at . The crater is in diameter and is located about west of Gale Crater (the landing location of NASA's "Curiosity" Mars rover on 6 August 2012). Robert Sharp Crater was named for geologist and planetary scientist Robert P. Sharp in 2012. | Natural_sciences | https://en.wikipedia.org/wiki?curid=35975518 | Robert Sharp (crater) |
Molecular-scale temperature The molecular-scale temperature is the defining property of the U.S. Standard Atmosphere, 1962. It is defined by the relationship: This is citation of the Technical Report of USAF from 1967. | Natural_sciences | https://en.wikipedia.org/wiki?curid=35981107 | Molecular-scale temperature |
Rahe (crater) Rahe is a crater on the planet Mars in the Tharsis quadrangle, positioned at 25.05° north latitude and 262.52° east longitude, between the volcanoes Ceraunius Tholus and Uranius Tholus. It measures approximately 34 kilometers in diameter and was named after Jürgen Rahe, a German-American astronomer and NASA science program director. The crater has an elongated shape measuring 35 km by 18 km and is the result of an oblique impact. A channel connects Rahe crater to the vicinity of the summit caldera of Ceraunius Tholus, with an interesting fan-shaped deposit at the lower end. Rahe Crater is 1 km deep in places, and was created by a low angle impact which is evident by its elongated shape and ejecta deposit in the shape of a “butterfly.” Rahe Crater is believed to once have held a lake. The lake was formed because heat from the nearby volcano Ceraunius Tholus melted glaciers. Melt water first collected in the caldera of Cerunius Tholus, and then spilled over the caldera rim forming a valley and the lake in Rahe Crater. The valley that carried the water was about 200 m wide. A delta formed where the valley entered Rahe Crater. This type of event involving volcanic heat melting glaciers is common in Iceland. Eruptions under glaciers are called jökulhlaups and average two each century. Studies of climate change show that many low-latitude regions accumulated large amounts of snow when the climate was different. | Natural_sciences | https://en.wikipedia.org/wiki?curid=36002618 | Rahe (crater) |
Robert S. Young is professor of coastal geology at Western Carolina University and director of the Program for the Study of Developed Shorelines. | Natural_sciences | https://en.wikipedia.org/wiki?curid=36018256 | Robert S. Young |
Peter Esben-Petersen (18 December 1869 in Sverup near Silkeborg – 2 April 1942 in Silkeborg) was a Danish entomologist who specialised in world Neuroptera. He was also interested in the Orthoptera, Ephemeroptera and other insects of Denmark. Esben-Petersen was a teacher in Silkeborg. He was associated with the entomological series Danmarks Flora og Fauna. For his scientific work on world fauna he received an honorary degree from the University of Copenhagen. His insect collection is conserved in the Zoological Museum in Copenhagen (mainly, some parts are in the Natural History Museum in Aarhus ). Partial list | Natural_sciences | https://en.wikipedia.org/wiki?curid=36029456 | Peter Esben-Petersen |
David Harper (palaeontologist) David A.T. Harper is a British palaeontologist, specialising in fossil brachiopods and numerical methods in palaeontology. He is Professor of Palaeontology in Earth Sciences, Principal of Van Mildert College, and Deputy Head of Colleges (Research and Scholarly Activities) in Durham University. In December 2014 he began his term as President of the Palaeontological Association. Harper was previously Professor of Palaeontology and Head of Geology in the Natural History Museum of Denmark, University of Copenhagen. He has published over 10 books and monographs, including a couple of influential textbooks, as well as over 250 scientific articles and, together with Øyvind Hammer, the widely used software package PAST. In recent years he has been addressing some of the major events in the history of life, for example the Cambrian Explosion, Great Ordovician Biodiversification Event and the end Ordovician mass extinctions. His research programmes have taken him to many parts of the world including Chile, China, Greenland, Russia and Tibet. His research has been recognized by foreign membership of the Royal Danish Academy of Sciences and Letters, an Einstein Professorship in the Chinese Academy of Sciences and a D.Sc. from Queen’s University Belfast. | Natural_sciences | https://en.wikipedia.org/wiki?curid=36035966 | David Harper (palaeontologist) |
Metal hydroxide Metal hydroxides are hydroxides of metals. Metal hydroxides are also known as strong bases. Many common metal hydroxides are made up from hydroxide ions and the ion of the particular metal that it is made up of. Example: When NaOH (sodium hydroxide) is dissolved in water, it forms OH ions and Na ions. Metal hydroxides ionize completely when dissolved, so that is why they are known as strong bases. Their pH is above 7, labeling them as bases. Since ions conduct electricity, metal hydroxides carry electricity very well when they are dissolved. In soils, it is assumed that larger amounts of natural phenols are released from decomposing plant litter rather than from throughfall in any natural plant community. Decomposition of dead plant material causes complex organic compounds to be slowly oxidized (lignin-like humus) or to break down into simpler forms (sugars and amino sugars, aliphatic and phenolic organic acids), which are further transformed into microbial biomass (microbial humus) or are reorganized, and further oxidized, into humic assemblages (fulvic and humic acids), which bind to clay minerals and metal hydroxides. | Natural_sciences | https://en.wikipedia.org/wiki?curid=36044328 | Metal hydroxide |
August Ferdinand Kuwert (15 October 1828, Nidden – 14 August 1894, Wernsdorf, südl. von Königsberg) was a German entomologist who specialised in Coleoptera. He was a Rittergutsbesitzer (owner of an estate or Junker) near the Prussian town of Wernsberg. Kuwert described many new species of Passalidae, Cleridae, Helophoridae, Hydrophilidae, Hydraenidae, Elmidae, Heteroceridae and Dryopidae. Partial list | Natural_sciences | https://en.wikipedia.org/wiki?curid=36055918 | August Ferdinand Kuwert |
List of sites and monuments in Kenya This is a list of sites and monuments of historic value that are maintained by the National Museums of Kenya. | Natural_sciences | https://en.wikipedia.org/wiki?curid=36057278 | List of sites and monuments in Kenya |
ANAEM The Ankara Nuclear Research and Training Center (), known as ANAEM, is a nuclear research and training center of Turkey. The organization was established on August 18, 2010 as a subunit of Turkish Atomic Energy Administration (, TAEK) in its campus at Ankara University's Faculty of Science situated in Beşevler neighborhood in central Ankara. The organization consists of three divisions, which are engaged in education, training and public relations on nuclear matters. | Natural_sciences | https://en.wikipedia.org/wiki?curid=36057380 | ANAEM |
Warren Samuel Fisher (1878–1971) was an American entomologist who specialised in Coleoptera. He was employed by the National Museum of Natural History in Washington. Fisher was especially interested in Buprestidae and Cerambycidae. | Natural_sciences | https://en.wikipedia.org/wiki?curid=36057709 | Warren Samuel Fisher |
UGC 5497 is a dwarf galaxy, located about 12 million light years away in the constellation Ursa Major. It is a member of the M81 Group. | Natural_sciences | https://en.wikipedia.org/wiki?curid=36106398 | UGC 5497 |
Edward Alexander Newell Arber (5 August 1870, London - 14 June 1918, Cambridge) was an English botanist and paleontologist. He was a Professor at the University of Cambridge specialising in palaeobotany. Partial list | Natural_sciences | https://en.wikipedia.org/wiki?curid=36158900 | Edward Alexander Newell Arber |
Nikolai Cholodny Nikolai Grigoryevich Cholodny (; 22 June 1882 – 4 May 1953) was an influential microbiologist who worked at the University of Kiev, Ukraine in the USSR during the 1930s. He is known for the Cholodny–Went model, which he developed independently with Frits Warmolt Went of the California Institute of Technology. Despite being associated with the same theory, the two men never actually met. Cholodny worked in the A.V. Fomin Botanical Garden, attached to the University of Kiev. He was one of the pioneers of the concept that microbes adhere to surfaces, using the technique of first placing glass slides in earth for a measured time period, then using a microscope to examine the slides. The Prokaryote "Leptothrix cholodnii" is named after him. In 1927 Cholodny proposed that the cells of the coleoptile are first polarized under the influence of uneven exposure to light, so growth hormone can diffuse more rapidly towards the side in the shade than in any other direction. Went reached the same conclusion in 1928, and the two scientists' names have been attached to the controversial Cholodny–Went theory. Selected works include: In 1937 N. G. Cholodny and E. Ch. Sankewitsch published an article on "Influence of weak electric currents upon the growth of the coleoptile" in "Plant Physiology". The same year he published an article on "Charles Darwin and the modern theory of tropisms" in "Science" magazine. | Natural_sciences | https://en.wikipedia.org/wiki?curid=36172635 | Nikolai Cholodny |
HARPS-N HARPS-N, the High Accuracy Radial velocity Planet Searcher for the Northern hemisphere is a high-precision radial-velocity spectrograph, installed at the Italian Telescopio Nazionale Galileo, a 3.58-metre telescope located at the Roque de los Muchachos Observatory on the island of La Palma, Canary Islands, Spain. is the counterpart for the Northern Hemisphere of the similar HARPS instrument installed on the ESO 3.6 m Telescope at La Silla Observatory in Chile. It allows for planetary research in the northern sky which hosts the Cygnus and Lyra constellations. In particular it allows for detailed follow up research to Kepler mission planet candidates, which are located in the Cygnus constellation region. The instrument's main scientific goals are the discovery and characterization of terrestrial super-Earths by combining the measurements using transit photometry and doppler spectroscopy which provide both, the size and mass of the exoplanet. Based on the resulting density, rocky (terrestrial) Super-Earths can be distinguished from gaseous exoplanets. The Project is a collaboration between the Geneva Observatory (lead), the Center for Astrophysics in Cambridge (Massachusetts), the Universities of St. Andrews and Edinburgh, the Queen's University Belfast, the UK Astronomy Technology Centre and the Italian Istituto Nazionale di Astrofisica. First light on sky was obtained by on March 27, 2012 and official operations started on August 1, 2012. | Natural_sciences | https://en.wikipedia.org/wiki?curid=36174770 | HARPS-N |
Dark radiation (also dark electromagnetism) is a postulated type of radiation that mediates interactions of dark matter. By analogy to the way photons mediate electromagnetic interactions between particles in the Standard Model (called "baryonic matter" in cosmology), dark radiation is proposed to mediate interactions between dark matter particles. Similar to dark matter particles, the hypothetical dark radiation does not interact with Standard Model particles. There has been no notable evidence for the existence of such radiation, but since baryonic matter contains multiple interacting particle types, it is reasonable to suppose that dark matter does also. Moreover, it has been pointed out recently that the cosmic microwave background data seems to suggest that the number of effective neutrino degrees of freedom is more than 3.046, which is slightly more than the standard case for 3 types of neutrino. This extra degree of freedom could arise from having a non-trivial amount of dark radiation in the universe. One possible candidate for dark radiation is the sterile neutrino. | Natural_sciences | https://en.wikipedia.org/wiki?curid=36177989 | Dark radiation |
Thiosilanes As a family thiosilanes refers to compounds of the form RSSiR'H2 with a S-Si bond between organic groups. | Natural_sciences | https://en.wikipedia.org/wiki?curid=36190552 | Thiosilanes |
John Veevers John James Veevers (13 October 1930 – 12 August 2018) was an Australian Professor of Geology and a fellow of the Australian Academy of Science. Veevers is the son of George Stanley Veevers and Dulcie Annie (née James) and attended Newington College (1944–1947). In 1946 he won the Wigram Allen Scholarship, endowed by Sir George Wigram Allen, for General Proficiency. At the end of 1947 Veevers was named Dux of the College and received the Schofield Scholarship and Halse Rogers Prize. He went up to the University of Sydney and graduated as a Bachelor of Science in 1952 and a Master of Science in 1954. Veevers was a cadet geologist at the Bureau of Mineral Resources, Geology and Geophysics, Canberra, (1948–1951), rising to geologist (1952–1960) and senior geologist 1961–1967. In 1968, he was appointed as a senior lecturer at Macquarie University and has since been an Associate Professor, Professor and Adjunct Professor of the Department of Earth and Planetary Sciences. He was awarded his PhD in 1956 from Imperial College London. Veevers' multiple publications are held by the National Library of Australia. | Natural_sciences | https://en.wikipedia.org/wiki?curid=36193445 | John Veevers |
Blanketing effect The blanketing effect (also referred to as line blanketing or the line-blanketing effect) is the enhancement of the red or infrared regions of a stellar spectrum at the expense of the other regions, with an overall diminishing effect on the whole spectrum. The term originates in a 1928 article by astrophysicist Edward Arthur Milne, where it was used to describe the effects that the astronomical metals in a star's outer regions had on that star's spectrum. The name arose because the absorption lines act as a "blanket", causing the continuum temperature of the spectrum to rise over what it would have been if these lines were not present. Astronomical metals, which produce most of a star's spectral absorption lines, absorb a fraction of the star's radiant energy (a phenomenon known as the "blocking effect") and then re-emit it at a lower frequency as part of the "backwarming" effect. The combination of both these effects results in the position of stars in a color-color diagram to shift towards redder areas as the proportion of "metals" in them increases. The blanketing effect is thus highly dependent on the metallicity index of a star, which indicates the fraction of elements other than hydrogen and helium that compose it. | Natural_sciences | https://en.wikipedia.org/wiki?curid=36197961 | Blanketing effect |
Conversion electron Mössbauer spectroscopy (CEMS) is a Mössbauer spectroscopy technique based on conversion electron. The CEM spectrum can be obtained either by collecting essentially all the electrons leaving the surface (integral technique), or by selecting the ones in a given energy range by means of a beta ray spectrometer (differential or depth selective CEMS). This method allows the use of simple and inexpensive detecting equipment, mainly flow-type proportional detectors in which large counting rates can be obtained. This last characteristic makes possible the study of samples with the natural abundance of the Mössbauer isotope. The information furnished by the integral measurements can be increased by using various angles of incidence or by depositing thin layers of inert material on the sample. In the energy range used in CEMS, the incident radiation can interact with the absorber through two kinds of processes: (a) conventional interactions – photoelectric and Compton effects, and (b) nuclear resonant absorption – Mössbauer effect. Due to conventional interactions the beam is attenuated and electrons are emitted from the sample. The nuclear de-excitation following the resonant absorption takes place by emission of either a gamma ray or an internal conversion (IC) electron. In the latter case, the atom is left in an ‘excited’ state with a hole in an inner shell; the energy excess is given away with emission of Auger electrons and/or X-rays | Natural_sciences | https://en.wikipedia.org/wiki?curid=36216090 | Conversion electron Mössbauer spectroscopy |
Conversion electron Mössbauer spectroscopy Thus, the electrons emitted from the sample as a consequence of the Mössbauer absorptions are: (a) primary (IC or Auger) electrons originated in the de-excitations of the nuclei excited by the incident beam, and (b) secondary electrons originated by conventional interactions of photons (or resonant absorption of gamma rays) emitted after resonant absorptions. | Natural_sciences | https://en.wikipedia.org/wiki?curid=36216090 | Conversion electron Mössbauer spectroscopy |
Beni Abbes Museum also known as (Béni Abbès Museum) () is an art museum located in oasis town of Beni Abbes, Béchar Province, Algeria. It is "a resource dedicated to desert fauna, fossils and Algerian arts and crafts." Béni Abbès Museum is popular in Algeria. It is supported by the Saharan Research Center. The museum houses displays desert fauna, fossils and traditional arts and crafts, such as carpets, wall hangings, ceramic items, woodcarvings and jewelry. The museum, which is supported by the Saharan Research Center, displays an extensive range of different types of dates. Dates are one of the mainstay crops of oasis towns and villages in Algeria. The oasis of Beni Abbes has its own myth. Local people claim that: The town of Beni Abbès is a popular tourist destination and the museum provides insights into its history and culture. | Natural_sciences | https://en.wikipedia.org/wiki?curid=36231456 | Beni Abbes Museum |
Meta-operator In theoretical physics, the word meta-operator is sometimes used to refer to a specific operation over a combination of operators, as in the example of path-ordering. A meta-operator is different from an operator in that it does not correspond to a linear transform in the Hilbert space. | Natural_sciences | https://en.wikipedia.org/wiki?curid=36235324 | Meta-operator |
Yao Tandong (; born July 1954 in Gansu) is a Chinese glaciologist, a member of the Chinese Academy of Sciences (CAS). He served as Director of the CAS Institute of Tibetan Plateau Research (ITP) in Beijing. He is the first Asian scientist to win the prestigious Vega Medal in 2017 in the fields of anthropology and geography for his contribution to research on glaciers and the environment on the Tibetan Plateau. Yao received his B.S. in 1978 and M.S in 1982 both from the Department of Geography, Lanzhou University in Gansu, China. He received his Ph.D from the Institute of Geographic Sciences and Natural Resources Research (IGSNRR), Chinese Academy of Sciences (CAS) in 1986. He worked as post-doctor in France and the USA from 1987 to 1990. He worked at Cold and Arid Regions Environmental and Engineering Research Institute (CAREERI), CAS, which was formerly known as Lanzhou Institute of Glaciology and Geocryology, from 1990 to 2003 and was deputy director of the institute from 1995 to 2000 and director from 2000 to 2003. He has been director of the Institute of Tibetan Plateau Research (ITP), CAS since its founding in 2003. Yao received awards for his research including the Natural Science Award and the Ho Leung Ho Lee Prize. He was recognized by the Science Association of China with a "Distinguished Scientist of China" award in 2005. Yao was elected to the Chinese Academy of Sciences in 2007. | Natural_sciences | https://en.wikipedia.org/wiki?curid=36236193 | Yao Tandong |
John Grattan (1800, Dublin -1871) was an Irish naturalist and anthropologist. was an apothecary in Belfast. He had wide interests in natural history and was a member of the Belfast Natural History Society but is best known for his work on ancient Irish skulls collected by his friend Edmund Getty. He devised a system of skull measurements using an ingenious craniometer. "Grattan's work was almost contemporaneous with that of Anders Retzius, and nearly all of it was done before the German and French Schools had elaborated their schemes of skull measurements" | Natural_sciences | https://en.wikipedia.org/wiki?curid=36243239 | John Grattan |
William Bean (geologist) William Bean (1787–1866) was an English geologist and conchologist. He was a pioneer of Yorkshire geology. In 1859 he sold his collection of over 15,000 fossils (mostly from localities around Scarborough). The majority of his collection was purchased by the British Museum and the Yorkshire Philosophical Society. Bean described several new species of Mollusca, including the whelk "Beringius turtoni", named in honor of William Turton. Bean was associated with the "Magazine of Natural History", and was a friend of Joshua Alder and Albany Hancock. | Natural_sciences | https://en.wikipedia.org/wiki?curid=36246497 | William Bean (geologist) |
Robert Damon (1814 – 4 May 1889) was an English conchologist and geologist. Damon was at first a hosier and glover but with his son Robert Ferris Damon (1845–1929) he established a dealership in natural history specimens in Weymouth. The company supplied museums throughout North and South America, Australia and Europe with much Dorset geological material from the late 1840s to 1914. In 1860 Damon wrote "Geology of Weymouth and the Isles of Portland; with Notes on the Natural History of the Coast and Neighbourhood" which includes a map of the district, geological sections, plates of fossils, and coast views, in 1884 a second edition with archaeological notes was published. He also wrote (and published himself in 1857) "A catalogue of the shells of Great Britain and Ireland with their synonyms and authorities". Damon died aged 75 at his museum in Weymouth from heart disease. The species "Amoria damonii" Gray, and "Paramelania damoni" were named in his honor. | Natural_sciences | https://en.wikipedia.org/wiki?curid=36247158 | Robert Damon |
Anton Moro Anton Lazzaro Moro (1687 in San Vito al Tagliamento – 1764) was an Italian abbot, geologist and naturalist. He was one of the leading advocates of plutonism in the early debate that confronted plutonism to neptunism, making him described by some authors as an ultraplutonist. He was the first to discriminate sedimentary rocks from volcanic ones by studying the rocks of volcanic islands. In his study of the crustaceans, he discovered fossils petrified in mountains that led him to deduce those rocks were once buried in the sea. | Natural_sciences | https://en.wikipedia.org/wiki?curid=36291124 | Anton Moro |
Theory of the Earth was a publication by James Hutton which laid the foundations for geology. In it he showed that the Earth is the product of natural forces. What could be seen happening today, over long periods of time, could produce what we see in the rocks. It also hypothesized that the age of the Earth was much older than what biblical literalists claim. This idea, uniformitarianism, was used by Charles Lyell in his work, and Lyell's textbook was an important influence on Charles Darwin. The work was first published in 1788 by the Royal Society of Edinburgh, and later in 1795 as two book volumes. Hutton recognized that rocks record the evidence of the past action of processes which still operate today. He also anticipated natural selection, as follows: "Those which depart most from the best adapted constitution, will be the most liable to perish, while, on the other hand, those organised bodies, which most approach to the best constitution for the present circumstances, will be best adapted to continue, in preserving themselves and multiplying the individuals of their race". Hutton's prose hindered his theories. They were not taken seriously until 1802, when Edinburgh University mathematics professor John Playfair restated Hutton's geological ideas in clearer English. However, he left out Hutton's thoughts on evolution. Charles Lyell in the 1830s popularised the idea of an infinitely repeating cycle (of the erosion of rocks and the building up of sediment) | Natural_sciences | https://en.wikipedia.org/wiki?curid=36294056 | Theory of the Earth |
Theory of the Earth Lyell believed in gradual change, and thought even Hutton gave too much credit to catastrophic changes. Hutton's work was published in different forms and stages: | Natural_sciences | https://en.wikipedia.org/wiki?curid=36294056 | Theory of the Earth |
ViroMed Co., Ltd. (VM BioPharma in the US) is a biotechnology company located in Seoul, Korea with US presence in Atlanta and the San Francisco Bay Area. The company works on DNA and protein-based therapeutics for various life-threatening diseases, along with herbal-based medicines, and nutraceuticals. has five main products in its pipeline targeting cardiovascular disease, cancer, and immune-related disorder, with clinical trials in the US, Korea, and China. The company has established partnerships with global firms including Johnson & Johnson (Biologics Delivery Systems Group of Cordis Corp., USA), SBI Biotech (Japan), and Green Cross (Korea). The company also conducts preclinical developmental studies in the aspects of toxicology, efficacy and pharmacokinetics. Phase I and II clinical studies are also carried out. Co., Ltd. (ViroMed) was established in 1996 as ViroMedica Pacific, Inc., later changed to in 1999. The company is headquartered in Seoul, Korea with US presence in Atlanta, GA. has been listed on KOSDAQ (084990) since 2006. As of Jan. 6th, 2017, the total number of issued shares is 15,956,260 with market capitalization approximately at US$1.6 billion. VM202 is a DNA-based medicine designed to express two isoforms of hepatocyte growth factor (HGF), a protein known to induce the formation of new blood vessels and the growth of damaged nerve cells. Currently, VM202 is being tested for 4 major cardiovascular or neurological diseases | Natural_sciences | https://en.wikipedia.org/wiki?curid=36294209 | ViroMed |
ViroMed In all cases, VM202 is delivered by simple intramuscular injection around the affected site. A phase III study for painful diabetic peripheral neuropathy (VM202-DPN) has been successfully initiated in the US in 2016. As of May 2017, over 160 have been randomized in the US among whom over 140 patients have completed their first injections at 21 clinical sites. A phase III study for chronic, non-healing foot ulcer associated with diabetes (VM202-PAD) has received approval from the US FDA and will have patient enrollment in 2017 in the US. After successful phase I trial for coronary artery disease (VM202-CAD), a phase II study is planned as IRB review in clinical sites is currently underway in Korea. VM202 has also successfully completed a phase I/II for amyotrophic lateral sclerosis (VM202-ALS), also known as Lou Gehrig's disease, which received orphan drug status and fast track designation from the US FDA. Its phase II IND has been approved by the US FDA in 2016. In 2004, transferred VM202 and associated technologies to Beijing Northland Biotech for commercialization purposes; in 2018, VM202 continued on to phase III clinical trials in China. VM206 is a therapeutic cancer vaccine targeting HER2/neu positive breast or ovarian cancer. Her2/neu is over-expressed in about 30% of breast cancers and is strongly associated with poor prognosis. VM206 can elicit an immune response to HER2/neu, which is hoped to reduce the growth and recurrence rate of breast or ovarian cancer | Natural_sciences | https://en.wikipedia.org/wiki?curid=36294209 | ViroMed |
ViroMed VM501 is a re-engineered form of interleukin 11 (IL-11) targeting chemotherapy-induced thrombocytopenia (CIT) that is said to be less toxic than the existing FDA-approved drugs. According to its website, the company is involved in the following clinical trials: | Natural_sciences | https://en.wikipedia.org/wiki?curid=36294209 | ViroMed |
Induced stem cells (iSC) are stem cells derived from somatic, reproductive, pluripotent or other cell types by deliberate epigenetic reprogramming. They are classified as either totipotent (iTC), pluripotent (iPSC) or progenitor (multipotent – iMSC, also called an induced multipotent progenitor cell – iMPC) or unipotent – (iUSC) according to their developmental potential and degree of dedifferentiation. Progenitors are obtained by so-called direct reprogramming or directed differentiation and are also called induced somatic stem cells. Three techniques are widely recognized: In 1895 Thomas Morgan removed one of a frog's two blastomeres and found that amphibians are able to form whole embryos from the remaining part. This meant that the cells can change their differentiation pathway. In 1924 Spemann and Mangold demonstrated the key importance of cell–cell inductions during animal development. The reversible transformation of cells of one differentiated cell type to another is called metaplasia. This transition can be a part of the normal maturation process, or caused by an inducement. One example is the transformation of iris cells to lens cells in the process of maturation and transformation of retinal pigment epithelium cells into the neural retina during regeneration in adult newt eyes. This process allows the body to replace cells not suitable to new conditions with more suitable new cells. In Drosophila imaginal discs, cells have to choose from a limited number of standard discrete differentiation states | Natural_sciences | https://en.wikipedia.org/wiki?curid=36315057 | Induced stem cells |
Induced stem cells The fact that transdetermination (change of the path of differentiation) often occurs for a group of cells rather than single cells shows that it is induced rather than part of maturation. The researchers were able to identify the minimal conditions and factors that would be sufficient for starting the cascade of molecular and cellular processes to instruct pluripotent cells to organize the embryo. They showed that opposing gradients of bone morphogenetic protein (BMP) and Nodal, two transforming growth factor family members that act as morphogens, are sufficient to induce molecular and cellular mechanisms required to organize, "in vivo" or "in vitro", uncommitted cells of the zebrafish blastula animal pole into a well-developed embryo. Some types of mature, specialized adult cells can naturally revert to stem cells. For example, "chief" cells express the stem cell marker Troy. While they normally produce digestive fluids for the stomach, they can revert into stem cells to make temporary repairs to stomach injuries, such as a cut or damage from infection. Moreover, they can make this transition even in the absence of noticeable injuries and are capable of replenishing entire gastric units, in essence serving as quiescent "reserve" stem cells. Differentiated airway epithelial cells can revert into stable and functional stem cells in vivo | Natural_sciences | https://en.wikipedia.org/wiki?curid=36315057 | Induced stem cells |
Induced stem cells After injury, mature terminally differentiated kidney cells dedifferentiate into more primordial versions of themselves and then differentiate into the cell types needing replacement in the damaged tissue Macrophages can self-renew by local proliferation of mature differentiated cells. In newts, muscle tissue is regenerated from specialized muscle cells that dedifferentiate and forget the type of cell they had been. This capacity to regenerate does not decline with age and may be linked to their ability to make new stem cells from muscle cells on demand. A variety of nontumorigenic stem cells display the ability to generate multiple cell types. For instance, multilineage-differentiating stress-enduring (Muse) cells are stress-tolerant adult human stem cells that can self-renew. They form characteristic cell clusters in suspension culture that express a set of genes associated with pluripotency and can differentiate into endodermal, ectodermal and mesodermal cells both in vitro and in vivo. Other well-documented examples of transdifferentiation and their significance in development and regeneration were described in detail. Induced totipotent cells can be obtained by reprogramming somatic cells with somatic-cell nuclear transfer (SCNT). The process involves sucking out the nucleus of a somatic (body) cell and injecting it into an oocyte that has had its nucleus removed Using an approach based on the protocol outlined by Tachibana et al | Natural_sciences | https://en.wikipedia.org/wiki?curid=36315057 | Induced stem cells |
Induced stem cells , hESCs can be generated by SCNT using dermal fibroblasts nuclei from both a middle-aged 35-year-old male and an elderly, 75-year-old male, suggesting that age-associated changes are not necessarily an impediment to SCNT-based nuclear reprogramming of human cells. Such reprogramming of somatic cells to a pluripotent state holds huge potentials for regenerative medicine. Unfortunately, the cells generated by this technology, potentially are not completely protected from the immune system of the patient (donor of nuclei), because they have the same mitochondrial DNA, as a donor of oocytes, instead of the patients mitochondrial DNA. This reduces their value as a source for autologous stem cell transplantation therapy, as for the present, it is not clear whether it can induce an immune response of the patient upon treatment. Induced androgenetic haploid embryonic stem cells can be used instead of sperm for cloning. These cells, synchronized in M phase and injected into the oocyte can produce viable offspring. These developments, together with data on the possibility of unlimited oocytes from mitotically active reproductive stem cells, offer the possibility of industrial production of transgenic farm animals | Natural_sciences | https://en.wikipedia.org/wiki?curid=36315057 | Induced stem cells |
Induced stem cells Repeated recloning of viable mice through a SCNT method that includes a histone deacetylase inhibitor, trichostatin, added to the cell culture medium, show that it may be possible to reclone animals indefinitely with no visible accumulation of reprogramming or genomic errors However, research into technologies to develop sperm and egg cells from stem cells raises bioethical issues. Such technologies may also have far-reaching clinical applications for overcoming cytoplasmic defects in human oocytes. For example, the technology could prevent inherited mitochondrial disease from passing to future generations. Mitochondrial genetic material is passed from mother to child. Mutations can cause diabetes, deafness, eye disorders, gastrointestinal disorders, heart disease, dementia and other neurological diseases. The nucleus from one human egg has been transferred to another, including its mitochondria, creating a cell that could be regarded as having two mothers. The eggs were then fertilised and the resulting embryonic stem cells carried the swapped mitochondrial DNA. As evidence that the technique is safe author of this method points to the existence of the healthy monkeys that are now more than four years old – and are the product of mitochondrial transplants across different genetic backgrounds. In late-generation telomerase-deficient (Terc−/−) mice, SCNT-mediated reprogramming mitigates telomere dysfunction and mitochondrial defects to a greater extent than iPSC-based reprogramming | Natural_sciences | https://en.wikipedia.org/wiki?curid=36315057 | Induced stem cells |
Induced stem cells Other cloning and totipotent transformation achievements have been described. Recently some researchers succeeded to get the totipotent cells without the aid of SCNT. Totipotent cells were obtained using the epigenetic factors such as oocyte germinal isoform of histone. Reprogramming in vivo, by transitory induction of the four factors Oct4, Sox2, Klf4 and c-Myc in mice, confers totipotency features. Intraperitoneal injection of such in vivo iPS cells generates embryo-like structures that express embryonic and extraembryonic (trophectodermal) markers. The developmental potential of mouse pluripotent stem cells to yield both embryonic and extra-embryonic lineages also can be expanded by microRNA miR-34a deficiency leading to strong induction of endogenous retroviruses MuERV-L (MERVL). iPSc were first obtained in the form of transplantable teratocarcinoma induced by grafts taken from mouse embryos. Teratocarcinoma formed from somatic cells. Genetically mosaic mice were obtained from malignant teratocarcinoma cells, confirming the cells' pluripotency. It turned out that teratocarcinoma cells are able to maintain a culture of pluripotent embryonic stem cell in an undifferentiated state, by supplying the culture medium with various factors. In the 1980s, it became clear that transplanting pluripotent/embryonic stem cells into the body of adult mammals, usually leads to the formation of teratomas, which can then turn into a malignant tumor teratocarcinoma | Natural_sciences | https://en.wikipedia.org/wiki?curid=36315057 | Induced stem cells |
Induced stem cells However, putting teratocarcinoma cells into the embryo at the blastocyst stage, caused them to become incorporated in the inner cell mass and often produced a normal chimeric (i.e. composed of cells from different organisms) animal. This indicated that the cause of the teratoma is a dissonance - mutual miscommunication between young donor cells and surrounding adult cells (the recipient's so-called "niche"). In August 2006, Japanese researchers circumvented the need for an oocyte, as in SCNT. By reprograming mouse embryonic fibroblasts into pluripotent stem cells via the ectopic expression of four transcription factors, namely Oct4, Sox2, Klf4 and c-Myc, they proved that the overexpression of a small number of factors can push the cell to transition to a new stable state that is associated with changes in the activity of thousands of genes. Reprogramming mechanisms are thus linked, rather than independent and are centered on a small number of genes. IPSC properties are very similar to ESCs. iPSCs have been shown to support the development of all-iPSC mice using a tetraploid (4n) embryo, the most stringent assay for developmental potential. However, some genetically normal iPSCs failed to produce all-iPSC mice because of aberrant epigenetic silencing of the imprinted Dlk1-Dio3 gene cluster. A team headed by Hans Schöler (who discovered the Oct4 gene back in 1989) showed that Oct4 overexpression drives massive off-target gene activation during reprogramming deteriorating the quality of iPSCs | Natural_sciences | https://en.wikipedia.org/wiki?curid=36315057 | Induced stem cells |
Induced stem cells Comparing to OSKM (Oct4, Sox2, Klf4 and c-Myc)that show abnormal imprinting and differentiation patterns, SKM (Sox2, Klf4 and c-Myc) reprogramming generates iPSCs with high developmental potential (nearly 20-fold higher than that of OSKM) equivalent to embryonic stem cell, as determined by their ability to generate all-iPSC mice through tetraploid embryo complementation An important advantage of iPSC over ESC is that they can be derived from adult cells, rather than from embryos. Therefore, it became possible to obtain iPSC from adult and even elderly patients. Reprogramming somatic cells to iPSC leads to rejuvenation. It was found that reprogramming leads to telomere lengthening and subsequent shortening after their differentiation back into fibroblast-like derivatives. Thus, reprogramming leads to the restoration of embryonic telomere length, and hence increases the potential number of cell divisions otherwise limited by the Hayflick limit. However, because of the dissonance between rejuvenated cells and the surrounding niche of the recipient's older cells, the injection of his own iPSC usually leads to an immune response, which can be used for medical purposes, or the formation of tumors such as teratoma. The reason has been hypothesized to be that some cells differentiated from ESC and iPSC in vivo continue to synthesize embryonic protein isoforms. So, the immune system might detect and attack cells that are not cooperating properly | Natural_sciences | https://en.wikipedia.org/wiki?curid=36315057 | Induced stem cells |
Induced stem cells A small molecule called MitoBloCK-6 can force the pluripotent stem cells to die by triggering apoptosis (via cytochrome c release across the mitochondrial outer membrane) in human pluripotent stem cells, but not in differentiated cells. Shortly after differentiation, daughter cells became resistant to death. When MitoBloCK-6 was introduced to differentiated cell lines, the cells remained healthy. The key to their survival, was hypothesized to be due to the changes undergone by pluripotent stem cell mitochondria in the process of cell differentiation. This ability of MitoBloCK-6 to separate the pluripotent and differentiated cell lines has the potential to reduce the risk of teratomas and other problems in regenerative medicine. In 2012 other small molecules (selective cytotoxic inhibitors of human pluripotent stem cells – hPSCs) were identified that prevented human pluripotent stem cells from forming teratomas in mice. The most potent and selective compound of them (PluriSIn #1) inhibits stearoyl-coA desaturase (the key enzyme in oleic acid biosynthesis), which finally results in apoptosis. With the help of this molecule the undifferentiated cells can be selectively removed from culture. An efficient strategy to selectively eliminate pluripotent cells with teratoma potential is targeting pluripotent stem cell-specific antiapoptotic factor(s) (i.e., survivin or Bcl10). A single treatment with chemical survivin inhibitors (e.g | Natural_sciences | https://en.wikipedia.org/wiki?curid=36315057 | Induced stem cells |
Induced stem cells , quercetin or YM155) can induce selective and complete cell death of undifferentiated hPSCs and is claimed to be sufficient to prevent teratoma formation after transplantation. However, it is unlikely that any kind of preliminary clearance, is able to secure the replanting iPSC or ESC. After the selective removal of pluripotent cells, they re-emerge quickly by reverting differentiated cells into stem cells, which leads to tumors. This may be due to the disorder of let-7 regulation of its target Nr6a1 (also known as Germ cell nuclear factor - GCNF), an embryonic transcriptional repressor of pluripotency genes that regulates gene expression in adult fibroblasts following micro-RNA miRNA loss. Teratoma formation by pluripotent stem cells may be caused by low activity of PTEN enzyme, reported to promote the survival of a small population (0.1–5% of total population) of highly tumorigenic, aggressive, teratoma-initiating embryonic-like carcinoma cells during differentiation. The survival of these teratoma-initiating cells is associated with failed repression of Nanog as well as a propensity for increased glucose and cholesterol metabolism. These teratoma-initiating cells also expressed a lower ratio of p53/p21 when compared to non-tumorigenic cells. In connection with the above safety problems, the use iPSC for cell therapy is still limited. However, they can be used for a variety of other purposes - including the modeling of disease, screening (selective selection) of drugs, toxicity testing of various drugs | Natural_sciences | https://en.wikipedia.org/wiki?curid=36315057 | Induced stem cells |
Induced stem cells The tissue grown from iPSCs, placed in the "chimeric" embryos in the early stages of mouse development, practically do not cause an immune response (after the embryos have grown into adult mice) and are suitable for autologous transplantation At the same time, full reprogramming of adult cells in vivo within tissues by transitory induction of the four factors Oct4, Sox2, Klf4 and c-Myc in mice results in teratomas emerging from multiple organs. Furthermore, partial reprogramming of cells toward pluripotency in vivo in mice demonstrates that incomplete reprogramming entails epigenetic changes (failed repression of Polycomb targets and altered DNA methylation) in cells that drive cancer development. By using solely small molecules, Deng Hongkui and colleagues demonstrated that endogenous "master genes" are enough for cell fate reprogramming. They induced a pluripotent state in adult cells from mice using seven small-molecule compounds. The effectiveness of the method is quite high: it was able to convert 0.02% of the adult tissue cells into iPSCs, which is comparable to the gene insertion conversion rate. The authors note that the mice generated from CiPSCs were "100% viable and apparently healthy for up to 6 months". So, this chemical reprogramming strategy has potential use in generating functional desirable cell types for clinical applications. In 2015 a robust chemical reprogramming system was established with a yield up to 1,000-fold greater than that of the previously reported protocol | Natural_sciences | https://en.wikipedia.org/wiki?curid=36315057 | Induced stem cells |
Induced stem cells So, chemical reprogramming became a promising approach to manipulate cell fates. The fact that human iPSCs capable of forming teratomas not only in humans but also in some animal body, in particular in mice or pigs, allowed to develop a method for differentiation of iPSCs in vivo. For this purpose, iPSCs with an agent for inducing differentiation into target cells are injected to genetically modified pig or mouse that has suppressed immune system activation on human cells. The formed teratoma is cut out and used for the isolation of the necessary differentiated human cells by means of monoclonal antibody to tissue-specific markers on the surface of these cells. This method has been successfully used for the production of functional myeloid, erythroid and lymphoid human cells suitable for transplantation (yet only to mice). Mice engrafted with human iPSC teratoma-derived hematopoietic cells produced human B and T cells capable of functional immune responses. These results offer hope that in vivo generation of patient customized cells is feasible, providing materials that could be useful for transplantation, human antibody generation and drug screening applications. Using MitoBloCK-6 and/or PluriSIn # 1 the differentiated progenitor cells can be further purified from teratoma forming pluripotent cells | Natural_sciences | https://en.wikipedia.org/wiki?curid=36315057 | Induced stem cells |
Induced stem cells The fact, that the differentiation takes place even in the teratoma niche, offers hope that the resulting cells are sufficiently stable to stimuli able to cause their transition back to the dedifferentiated (pluripotent) state and therefore safe. A similar in vivo differentiation system, yielding engraftable hematopoietic stem cells from mouse and human iPSCs in teratoma-bearing animals in combination with a maneuver to facilitate hematopoiesis, was described by Suzuki et al. They noted that neither leukemia nor tumors were observed in recipients after intravenous injection of iPSC-derived hematopoietic stem cells into irradiated recipients. Moreover, this injection resulted in multilineage and long-term reconstitution of the hematolymphopoietic system in serial transfers. Such system provides a useful tool for practical application of iPSCs in the treatment of hematologic and immunologic diseases. For further development of this method animal in which is grown the human cell graft, for example mouse, must have so modified genome that all its cells express and have on its surface human SIRPα. To prevent rejection after transplantation to the patient of the allogenic organ or tissue, grown from the pluripotent stem cells in vivo in the animal, these cells should express two molecules: CTLA4-Ig, which disrupts T cell costimulatory pathways and PD-L1, which activates T cell inhibitory pathway. See also: | Natural_sciences | https://en.wikipedia.org/wiki?curid=36315057 | Induced stem cells |
Induced stem cells In the near-future, clinical trials designed to demonstrate the safety of the use of iPSCs for cell therapy of the people with age-related macular degeneration, a disease causing blindness through retina damaging, will begin. There are several articles describing methods for producing retinal cells from iPSCs and how to use them for cell therapy. Reports of iPSC-derived retinal pigmented epithelium transplantation showed enhanced visual-guided behaviors of experimental animals for 6 weeks after transplantation. However, clinical trials have been successful: ten patients suffering from retinitis pigmentosa have had their eyesight restored – including a woman who had only 17 percent of her vision left. Chronic lung diseases such as idiopathic pulmonary fibrosis and cystic fibrosis or chronic obstructive pulmonary disease and asthma are leading causes of morbidity and mortality worldwide with a considerable human, societal and financial burden. So there is an urgent need for effective cell therapy and lung tissue engineering. Several protocols have been developed for generation of the most cell types of the respiratory system, which may be useful for deriving patient-specific therapeutic cells. Some lines of iPSCs have the potentiality to differentiate into male germ cells and oocyte-like cells in an appropriate niche (by culturing in retinoic acid and porcine follicular fluid differentiation medium or seminiferous tubule transplantation) | Natural_sciences | https://en.wikipedia.org/wiki?curid=36315057 | Induced stem cells |
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