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When the Great Equalizer Shuts Down: Schools, Peers, and Parents in Pandemic Times
Agostinelli, Francesco
Doepke, Matthias
Sorrenti, Giuseppe
Zilibotti, Fabrizio
Matthias Doepke
What are the effects of school closures during the Covid-19 pandemic on children's education? Online education is an imperfect substitute for in-person learning, particularly for children from low-income families. Peer effects also change: schools allow children from different socio-economic backgrounds to mix together, and this effect is lost when schools are closed. Another factor is the response of parents, some of whom compensate for the changed environment through their own efforts, while others are unable to do so. We examine the interaction of these factors with the aid of a structural model of skill formation. We find that school closures have a large and persistent effect on educational outcomes that is highly unequal. High school students from poor neighborhoods suffer a learning loss of 0.4 standard deviations, whereas children from rich neighborhoods remain unscathed. The channels operating through schools, peers, and parents all contribute to growing educational inequality during the pandemic.
Agostinelli, Francesco & Doepke, Matthias & Sorrenti, Giuseppe & Zilibotti, Fabrizio, 2020. "When the Great Equalizer Shuts Down: Schools, Peers, and Parents in Pandemic Times," CEPR Discussion Papers 15606, C.E.P.R. Discussion Papers.
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Guido Neidhöfer & Nora Lustig & Mariano Tommasi, 2021. "Intergenerational transmission of lockdown consequences: Prognosis of the longer-run persistence of COVID-19 in Latin America," Working Papers 148, Universidad de San Andres, Departamento de Economia, revised Mar 2021.
Guido Neidhöfer & Nora Lustig & Mariano Tommasi, 2021. "Intergenerational transmission of lockdown consequences: Prognosis of the longer-run persistence of COVID-19 in Latin America," Working Papers 2104, Tulane University, Department of Economics.
Neidhöfer, Guido & Lustig, Nora & Tommasi, Mariano, 2021. "Intergenerational transmission of lockdown consequences: Prognosis of the longer-run persistence of COVID-19 in Latin America," ZEW Discussion Papers 21-046, ZEW - Leibniz Centre for European Economic Research.
Guido Neidhoefer & Nora Lustig & Mariano Tommasi, 2021. "Intergenerational transmission of lockdown consequences: Prognosis of the longer-run persistence of COVID-19 in Latin America," Working Papers 571, ECINEQ, Society for the Study of Economic Inequality.
Kiessling, Lukas, 2021. "How do parents perceive the returns to parenting styles and neighborhoods?," European Economic Review, Elsevier, vol. 139(C).
Lukas Kiessling, 2020. "How Do Parents Perceive the Returns to Parenting Styles and Neighborhoods?," Discussion Paper Series of the Max Planck Institute for Research on Collective Goods 2020_14, Max Planck Institute for Research on Collective Goods.
Lukas Kiessling, 2021. "How Do Parents Perceive the Returns to Parenting Styles and Neighborhoods?," CRC TR 224 Discussion Paper Series crctr224_2021_270v2, University of Bonn and University of Mannheim, Germany.
Santiago Pereda-Fernández, 2017. "Social Spillovers in the Classroom: Identification, Estimation and Policy Analysis," Economica, London School of Economics and Political Science, vol. 84(336), pages 712-747, October.
Agostinelli, Francesco & Avitabile, Ciro & Bobba, Matteo, 2021. "Enhancing Human Capital at Scale," IZA Discussion Papers 14192, Institute of Labor Economics (IZA).
Francesco Agostinelli & Ciro Avitable & Matteo Bobba, 2021. "Enhancing Human Capital at Scale," Working Papers 2021-012, Human Capital and Economic Opportunity Working Group.
Michael D. König & Xiaodong Liu & Yves Zenou, 2019. "R&D Networks: Theory, Empirics, and Policy Implications," The Review of Economics and Statistics, MIT Press, vol. 101(3), pages 476-491, July.
König, Michael & Liu, Xiaodong & Zenou, Yves, 2014. "R&D Networks: Theory, Empirics and Policy Implications," CEPR Discussion Papers 9872, C.E.P.R. Discussion Papers.
Michael D. Koenig & Xiaodong Liu & Yves Zenou, 2014. "R&D Networks: Theory, Empirics and Policy Implications," Discussion Papers 13-027, Stanford Institute for Economic Policy Research.
Alipour, Jean-Victor & Fadinger, Harald & Schymik, Jan, 2021. "My home is my castle – The benefits of working from home during a pandemic crisis," Journal of Public Economics, Elsevier, vol. 196(C).
Berlinski,Samuel G. & Ferreyra,Maria Marta & Flabbi,Luca & Martin,Juan David, 2020. "Child Care Markets, Parental Labor Supply, and Child Development," Policy Research Working Paper Series 9427, The World Bank.
Samuel Berlinski & Maria Marta Ferreyra & Luca Flabbi & Juan David Martin, 2020. "Child Care Markets, Parental Labor Supply, and Child Development," CHILD Working Papers Series 73 JEL Classification:, Centre for Household, Income, Labour and Demographic Economics (CHILD) - CCA.
Berlinski, Samuel & Ferreyra, María Marta & Flabbi, Luca & Martin, Juan David, 2020. "Child Care Markets, Parental Labor Supply, and Child Development," IDB Publications (Working Papers) 10859, Inter-American Development Bank.
Berlinski, Samuel & Ferreyra, Maria Marta & Flabbi, Luca & Martin, Juan David, 2020. "Child Care Markets, Parental Labor Supply, and Child Development," IZA Discussion Papers 12904, Institute of Labor Economics (IZA).
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COVID-19; neighborhood effects; Pandemics; Parenting; parenting style; peer effects; skill acquisition;
I24 - Health, Education, and Welfare - - Education - - - Education and Inequality
J13 - Labor and Demographic Economics - - Demographic Economics - - - Fertility; Family Planning; Child Care; Children; Youth
J24 - Labor and Demographic Economics - - Demand and Supply of Labor - - - Human Capital; Skills; Occupational Choice; Labor Productivity
R20 - Urban, Rural, Regional, Real Estate, and Transportation Economics - - Household Analysis - - - General
NEP-URE-2021-05-17 (Urban & Real Estate Economics)
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It's late in the morning. The sun, with its strong rays, pierces through the blinds. Its intense white light washes out all other colors. A heightened aromatic, tender and powerful. The dew gives way to clarity.


text:
RESOLUTION OF THE CABINET OF MINISTERS OF THE REPUBLIC OF UZBEKISTAN
of February 5, 2004 No. 57
About further implementation of market mechanisms of realization of highly liquid types of products, raw materials and materials
For the purpose of widespread introduction of the market principles and mechanisms of sales of products, liquidation of centralized distributive system, creation of equal conditions of access to material resources of all business entities, irrespective of pattern of ownership, enhancement of the mechanism of forming of market prices the Cabinet of Ministers decides:
1. Approve:
the list of types of products by which distribution of limits between republican consumers, according to appendix No. 1 is abolished;
the list of strategic types of material resources by which the special procedure for their realization, according to appendix No. 2 is established;
Regulations on special procedure for realization of strategic types of material resources according to appendix No. 3;
Actions for implementation of market mechanisms of sales of products according to appendix No. 4.
Take into consideration that the procedure for market realization of cotton fiber is determined by the resolution of the Cabinet of Ministers of June 3, 2003 No. 240 "About enhancement of the mechanism of calculations for the made and implementable cotton fiber"
2. Determine that:
exposure to the exchange biddings and auctions of products for lists according to appendices No. No. 1 and 2 is performed according to the amounts provided on these purposes in the corresponding material balances approved in accordance with the established procedure. The Ministry of Economics of the Republic of Uzbekistan quarterly and monthly schedules of accomplishment of the approved parameters of material balances to the ministries, departments, economic associations and the companies, regarding sales of products, raw materials and materials through the exchange biddings - to the State committee of the Republic of Uzbekistan on demonopolization and development of the competition are led up at the scheduled time. Based on the specified schedules of the ministry, department, economic associations and the companies are developed and claimed in coordination with the State committee of the Republic of Uzbekistan on privatization, demonopolization and development of the competition of graphics of exposure of products to the exchange biddings on terms according to established procedure, and the last brings them to the exchange;
the exchanges shall publish on weekly basis in open seal and on the pages on the Internet the weighted average stock exchange quotations of the prices of the goods sold specified in appendices No. 1 and 2, and the prices which developed at auctions following the results of their carrying out;
products of enterprise monopolists included in appendices No. 1 and 2, can be sold in the domestic market under direct agreements, and also at the exchange (auction) biddings. At the same time sales of products under direct agreements (except for amounts of products sold for the state needs, replenishment and refreshening of resources of the state strategic reserve, production under the state order, intra-branch needs of producers on limits to separate categories of consumers, the electric power, natural gas and aviation fuel) is performed on the weighted average prices of stock (auction) exchange quotations published for the last date;
realization under direct agreements of products intended according to material balances to realization at the exchange (auction) biddings can be performed only in the amounts unclaimed within one month from the moment of exposure at the exchange (auction) biddings, on the weighted average prices which developed by results of the exchange biddings for the last week;
in case of realization of exclusive products by enterprise monopolists through the exchange biddings and auctions, and also under direct agreements on weighted average prices of stock (auction) exchange quotations, sanctions for exceeding of the declared marginal price, stipulated by the legislation about the competition are not applied to them.
In case of violation of schedules of exposure to the exchange biddings of highly liquid and exclusive types of products on terms and amounts are subject to withdrawal:
the funds received over the starting price from sales of products under direct agreements including for export, in the amounts distracted from the exchange biddings;
the means received for the account of growth of exchange prices because of not exposure of products to the exchange biddings.
Withdrawal of the specified means is performed according to the procedure, provided for enterprise monopolists in case of violation of established procedure of forming and use of the prices (rates).
The conclusion of agreements on products included in appendices No. 1 and 2, purchased at the exchange biddings (auctions) and for direct agreements (except for the electric power and natural gas), is performed on the terms of complete advance payment or drawing of the irrevocable letter of credit for each delivered batch. At the same time stock exchange transactions are concluded with introduction by the seller and the buyer of means of warranty providing at the rate to 10 percent from total cost of the goods exposed on the exchange biddings and amount of the expected transaction, respectively, with carrying out calculations through clearing house.
3. Determine that reducing supply of natural gas for failure to pay to the companies specified in appendix No. 5, can be performed in accordance with the established procedure to the level of technology and emergency armor of power supply, and blackout - only by a court decision.
4. Determine that products included in appendix No. 2, acquired by consumers at regulated prices, are used only in the production purposes and is not subject to resale.
In case of identification of the facts of resale of the resources acquired by consumers at regulated prices, and also the resources specified in appendices No. No. 1 and 2 to this resolution, acquired by consumers at the exchange biddings and prohibited to resale, that the gained income from resale is withdrawn according to the procedure provided by the resolution of the Cabinet of Ministers of October 28, 2010 No. 239 "About measures for further enhancement of procedure for declaring (approval) and establishment of regulated prices (rates) for goods (works, services).
The heads of the companies who allowed the facts of resale of resources bear responsibility in the procedure established by the legislation, up to criminal.

redpajama_set_name: RedPajamaCommonCrawl


Amongst natural polymers, silk proteins constitute a promising new material due to their biocompatibility and biodegradability. Recently, materials made of recombinantly produced spider silk proteins or silkworm fibroin have been shown to be well tolerated by cells.11–16 In this respect, particles made of eADF4(C16) have been previously used as drug delivery vehicles. eADF4(C16) is based on the repetitive core domain of the spidroin ADF4 of the European garden spider Araneus diadematus and can be processed into different morphologies including films,17,18 hydrogels,19 non-woven mats,20 capsules,21,22 and particles.23,24 Particles are produced with adjustable particle size by salting out, upon varying either protein concentration or mixing intensity with the salting-out reagent.24 Diameters of particles were in the range of 250 nm to 3 μm. Generally, cellular uptake of silk particles is rare13,25,26 probably due to the size of the particles, lack of binding ligands or the negative net/surface charge of some silk proteins.
Endocytosis plays an important role in various unspecific and specific functions (e.g. nutrient uptake, signal transduction, regulation mechanism of cell migration, shape and volume, transcellular transport) of a cell. For the identification of internalization of substances, particles, etc. pharmacological inhibitors are commonly used. The choice of an inhibitor for uptake studies is not easy because many are not very specific or cause side effects. Ivanov51 compared the commonly used inhibitors for different endocytotic pathways. Based on this comparison dansylcadaverine and di-methyl-amiloride are the favourable inhibitors of clathrin-mediated endocytosis and macropinocytosis due to specificity and low side effects. These inhibitors were here used to determine the cellular uptake route of the individual spider silk particles.
eADF4(C16) is based on 16 repeats of the consensus sequence of spidroin ADF4 of the European garden spider (Araneus diadematus) (C-module: GSSAAAAAAAASGPGGY GPENQGPSGPGGYGPGGPG), and a T7-tag fused to the aminoterminus for detection purposes.52 Fusions were made using tags as described in Wohlrab et al.49 For each tag, DNA cassettes were created by annealing two synthetic oligonucleotides (R8-peptide tag: gatccatgggccgtcgccgtcgtcgccgtcgccgtggctaatgaA and agctttcattagccacggcgacggcgacgacggcgacggcccatg; Tat aminoterminal tag: CATGGGCCGCAAAAAACGCCG CAGCGCCGTCGCGGCTAATGAAA and AGCTTTCATTAGCCGCGACGGCGCT GACGGCGTTTTTTGCGGCC; Tat carboxyterminal tag: CATGGGCCGCAAAAAACGCCGTCAGCGCCGTCGCCCGGGCTAATGAAA and AGCTTTCAT TAGCCCGGGCGACGGCGCTGACGGCGTTTTTTGCGGCC). The resulting amino acid sequences and the modified proteins are shown in Fig. 1. DNA sequences of the tags were inserted into the cloning vector pCS-eADF4(C16) by seamless cloning as described by Huemmerich et al.52 Successful cloning was confirmed by sequencing.
Recombinant ADF4 derivates were produced in E. coli as described previously.52 Proteins were purified after lysis using ultrasonication, centrifugation of the cell debris, heat denaturation of E. coli proteins (80 °C, 20 min) and their removal by a second centrifugation step. The soluble spider silk proteins remaining in the supernatant were precipitated using 20% ammonium sulfate at 25 °C and lyophilized. Isoelectric point (pI) and molecular weight (MW) of the recombinant proteins were calculated using ExPASy ProtParam (Table 1). eADF4(C16), eADF4(C16)RGD, eADF4(C16)R8G, eADF4(C16)Tat and eADF4(κ16) contain an aminoterminal T7-tag, whereas Tat-eADF4(C16) and Tat-eADF4(C16)Tat do not have this T7-tag due to the cloning and expression system. Due to the T7-tag eADF4(C16) has a higher molecular weight than Tat-eADF4(C16), and eADF4(C16)Tat has a higher molecular weight than Tat-eADF4(C16) and Tat-eADF4(C16)Tat.
Lyophilized proteins were dissolved in 1-ethyl-3-methyl-imidazolium acetate (EMiM[acetate]) and stirred for 1 h at 95 °C. Particle formation was initiated by mixing 0.1 mg ml−1 of protein in EMiM[acetate] with 5 fold v/v excess of 2 M potassium phosphate, pH 8.23,55 After incubation for 1 h at 25 °C, the particles were centrifuged (15 min, 17 000g, 4 °C) and washed three times with ultrapure water.
Spider silk and control particles (sicastar®-redF, surface modified with COOH or NH2 groups, micromod, Rostock, Germany) were analyzed for their particle size (Z-average and width) and distribution indices using dynamic light scattering (ZetaSizer NanoZS, Malvern Instruments, Worcestershire, UK). The samples were measured (n = 6; eADF4(c16)Tat n = 4) in MQ-H2O at a protein concentration of 0.5 mg ml−1 at 25 °C. The electrophoretic mobilities of all spider silk particles were measured in 10 mM KCl, pH 5.5 at 25 °C (ZetaSizer NanoZS). The zeta potential was calculated according to the theory of Smoluchowski56 based on the measured electrophoretic mobilities.
20 μl of particle suspension were pipetted on Thermanox™ plastic cover slips and air-dried. Samples were sputtered with a 2 nm layer of platinum (Sputter coater 208 HR, Cressington, Watford, UK) and analyzed using a Leo 1530 VP Gemini SEM (Zeiss, Germany) at 2–3 kV.
Cell samples were fixed with 2.5% v/v glutaraldehyde, 80 mM HEPES, 3 mM CaCl2, pH 7.3, and washed twice with fixation buffer without glutaraldehyde for 15 min. After washing two times with ultrapure water, the samples were dehydrated by incubation for 20 min in 25%, 50%, 70%, 95%, each, and three times in 100% acetone. Afterwards, all samples were critically point dried (transitional medium CO2, Balzers CPD 020), sputtered with a 2 nm layer of platinum and analyzed using a Leo 1540 CrossBeam VP Gemini SEM.
Colloidal stability of spider silk and control particles was analyzed in 10 mM KCl, pH 5.5 using a LUMiFuge®114 (L.U.M. GmbH, Berlin, Germany) with a rotation frequency of 300, 600 and 900 rpm and different time intervals of 200, 300, and 1000 s. Particle suspensions were placed in tubes in horizontal positions on the disc of the LUMiFuge®114. Transparency of the suspensions was measured in the area between menisci and sediment in duplicates, three times for each protein using fresh preparations each time. Transmission was measured every 10 s over 1800 s, and the integral of transmission between meniscus and bottom of the vial was plotted against time.
HeLa cells (ACC-57, German collection of microorganism and cell cultures DSMZ, Leibnitz Institute, Braunschweig, Germany) were cultured in Dulbecco's Modified Eagle Medium (DMEM) (Biochrom, Berlin, Germany) containing 10% v/v fetal bovine serum (Biochrom, Berlin, Germany), 1% v/v GlutaMAX (Gibco, Grand Island, USA) and 0.1% gentamicin sulfate (Sigma-Aldrich, Seelze, Germany). The viability of the cells was confirmed by trypan blue staining (Sigma-Aldrich, Seelze, Germany) before seeding the cells for experiments. Cells were cultured in a CO2-incubator (Haereus, Hanau, Germany) at 95% humidity, 5% CO2 and 37 °C.
For cell proliferation analysis, cells were seeded on treated 96-well cell culture plates (Nunc, Langenselbold, Germany) with a density of 5000 cells cm−2 for 9 days. Cells were pre-incubated with spider silk or control particles (9.6 ng μl−1) for 24 h at 37 °C. Medium was changed daily followed by analysis of cell vitality using the CellTiter Blue assay. Cells were washed two times with phosphate buffered saline (PBS). Fresh media containing 10% v/v CellTiter Blue reagent® (Promega, Madison, USA) was added, and cells incubated for 2.5 h at 37 °C. Transformation of the blue fluorescent dye resazurin into red fluorescent resorufin (λex = 530 nm; λem = 590 nm) was measured using a plate reader (Mithras LB 940, Berthold, Bad Wildbad, Germany) with 530 nm excitation and 600 nm emission filters and a counting time of 0.5 s. For each particle type, cell culture experiments were repeated 3 times with 3 replicates.
Proliferation rate (μ) and doubling time (Td) were calculated using a first order Monod-type kinetic model with the assumption that the mortality rate can be neglected (eqn (1)).
X(t) and X0 are the concentrations of viable cells at time points t and 0. For more details concerning the calculation of proliferation rate μ see Leal-Egana et al.20 The doubling time can be calculated using eqn (2).
HeLa cells were cultured on treated 6-well cell culture plates (Nunc, Langenselbold, Germany) with a density of 30 000 cells cm−2 in the presence of spider silk or control fluorescent particles for 6, 24, 48 and 72 h. Cells were washed with PBS twice, treated with trypan blue, washed again with PBS and pelleted using 0.05% Trypsin/EDTA and centrifugation (300g, 5 min, 25 °C). Cells were resuspended in fresh media, and uptake was measured using flow cytometry (Cytomics FC500, Beckman-Coulter, Krefeld, Germany). Cells only appeared fluorescent upon internalization of rhodamine-labeled particles (labeling via N-Hydroxysuccinimid ester chemistry19,57). Endocytotic inhibitors were used for identification of the underlying uptake mechanism. Cells were seeded at a density of 50 000 cells cm−2 with spider silk or control silica particles for 6 and 24 h. 100 μM dansylcadaverin (DC) for inhibition of clathrin-mediated endocytosis and 100 μM di-methyl-amiloride (DMA) for inhibition of macropinocytosis were added to cells 30 min prior to particle addition.
HeLa cells were cultured on μ-slides (8-well, ibidi GmbH, Martinsried, Germany) at a cell density of 20 000 cells cm−2 and incubated for 6, 24, 48 and 72 h with rhodamine-labeled particles at 37 °C. The cells were fixed with 4% w/v paraformaldehyde for 15 min at 25 °C, washed with PBS and permeabilized with 0.1% v/v Triton X-100 for 3 min. After two additional PBS washing steps, cells were incubated with HCS CellMask™ Blue stain (Invitrogen, Darmstadt, Germany) for 30 min and washed again with PBS. All samples were kept in PBS. Fluorescence microscopy was performed using a LifeCell microscope (DMI6000, Leica, Wetzlar, Germany).
Recombinant spider silk protein eADF4(C16) has been well investigated in recent years.19,22–24,49,55,58–62 Here, the protein was modified with different tags for stimulating internalization of respective protein particles by HeLa cells (Fig. 1). A Tat-peptide was fused either to the carboxy-, the aminoterminus or both termini of eADF4(C16), and an R8- or an RGD-peptide was fused with the aminoterminus of eADF4(C16).49 To study particle-charge-dependence of cellular uptake, the recently established positively charged eADF4(κ16) was used.50 In this variant, all glutamic acid residues of eADF4(C16) are replaced by lysine ones rendering the protein polycationic under neutral conditions (in contrast to polyanionic eADF4(C16)). All modifications were analyzed and confirmed by MALDI-TOF MS (data not shown).
Particles were produced by salting out of the protein dissolved in EMiM[acetate]. In contrast to previously published methods23 the ionic liquid EMiM[acetate] was used to minimize the particle diameter and distribution. In addition to "single-protein" particles also eADF4(C16) and eADF4(κ16) blend particles were produced.
All spider silk particles had spherical morphologies (Fig. 2A, Fig. S1†), indicating that modifying the sequence as well as blending had no influence on particle formation. Particles were also analyzed concerning size and surface potential (Table 2). Commercially available silica particles with a theoretical diameter of 100 nm were used as control. Their measured diameter was 113.5 ± 0.5 nm. Spider silk particles had diameters between 239 and 294 nm except for eADF4(κ16) (324 nm) and blend particles (393 nm). Importantly, the previously reported broad particle size distribution could be significantly reduced.24 Many studies investigated the uptake of particles produced from different materials such as polystyrene,63,64 chitosan based polymers,65 silica,66 or poly(lactic-co-glycolic acid) (PLGA).67 Independently from the material, the optimal particle size for uptake was in the range of 100–200 nm.
Fig. 2 SEM images (A) and colloidal stability analysis (B) of spider silk and control silica particles. For SEM, spider silk particles were prepared from a 0.1 mg ml−1 solution in EMiM[acetate] and analyzed in the dehydrated state. Colloidal stability of particles from a 2 mg ml−1 solution was determined in 10 mM KCl, pH 5.5. Scale bars: 100 nm.
Next, all particle suspensions were analyzed concerning their colloidal stability using a LUMiFuge®114 (Fig. 2B). Control silica particles were colloidally stable (no change in curve behavior) as suggested by their zeta potentials, whereas spider silk particles behaved differently. eADF4(C16) and eADF4(C16)RGD showed some sedimentation behavior at 300 and 600 rpm and started to sediment above 900 rpm, fitting with the measured zeta potentials of −26.7 and −24.8 mV. As expected, eADF4(C16)R8G, eADF4(C16)Tat and Tat-eADF4(C16) showed less colloidal stability, and eADF4(κ16) and blend particles were even less colloidally stable, with Tat-eADF4(C16)Tat particles being the least stable ones.
Cytotoxicity of spider silk and control silica particles was analyzed using the CellTiter Blue® assay over 9 days after particle addition (24 h). HeLa cells cultured in the presence of spider silk or control silica particles showed indistinguishable growth behavior in comparison to HeLa cells grown in the absence thereof. Proliferation rates (μ) and doubling times (Td) also showed no significant differences (Table 3). Therefore, none of the particles seemed to have any cytotoxic effect on HeLa cells.
HeLa cells were incubated with spider silk or control particles for 6, 24, 48 and 72 h at 37 °C and analyzed using flow cytometry (Fig. 3A) or fluorescence microscopy (Fig. 3B, shown for eADF4(C16), eADF4(κ16) and blends). After 6 h of incubation, all spider silk particles were indistinguishably internalized by HeLa cells (between 10 and 30% of cells showed internalized particles) except for eADF4(κ16) particles where 64% of the cells contained particles (Fig. 3A). After 24 h of incubation, 92% of the cells showed internalized eADF4(κ16) particles, after 48 h 95% and after 72 h 97%, with all of the cells containing more than one internalized particle (Fig. 3B). Similar internalization numbers have been previously reported for particles produced from silk fibroin and albumin.25 As expected, polyanionic eADF4(C16) particles were internalized by only 19% of the HeLa cells after 24 h, with the amount of cells not increasing after 48 and 72 h.
Fig. 3 Flow cytometry analysis (A) and fluorescence microscopy images (B; maximal projections) of HeLa cells incubated in the presence of 9.6 ng μl−1 of spider silk or control silica particles for 6, 24, 48, and 72 h (A). Cells were washed and treated with trypan blue, quenching the fluorescence of labeled particles outside the cells. (B) Cells were fixed, permeabilized and stained with HCS CellMask™ Blue Stain. Scale bars: 5 μm.
Blend particles were internalized from about 45% of the cells after 24 h, 57% after 48 h and 60% after 72 h, thus, the number of cells with internalized blend particles was between that of cells containing eADF4(C16) and eADF4(κ16) particles. Further, each cell (5000 cells measured per set) contained on average more blend particles than eADF4(C16) particles, but less than eADF4(κ16) particles. This result was expected since cells usually show a negative surface potential (HeLa cells approximately −50 mV69), and, therefore, charge–charge interactions with positively charged particles are pronounced.
The number of cells containing particles made of all CPP-fusion proteins was increased in comparison to that of eADF4(C16) alone. No significant differences were obtained when the Tat peptide was fused to the amino- or carboxyterminus or to both. Interestingly, the uptake of the CPP- and RGD-fusion particles was similar to that of blend particles.
To get a closer look at the internalization mechanism of spider silk particles, SEM visualization of cell surfaces was performed. The particles could be seen in different stages of internalization (Fig. 4). Furthermore, HeLa cells were cultured in the presence of different endocytotic inhibitors (dansylcadaverine (DC): inhibitor of clathrin-mediated endocytosis; di-methyl-amiloride (DMA): inhibitor of macropinocytosis51,70–72) before adding the silk particles. After particle addition, the cells were incubated for 6 and 24 h and analyzed using flow cytometry (Table 4 and Table S1†).
Fig. 4 SEM image of eADF4(κ16) particle uptake by HeLa cells after 24 h of incubation. The cells were fixed, dehydrated and critical point dried. The arrows indicate a particle on the surface (dashed) and a particle which is half-way internalized (line) at the moment the cells were fixed. Scale bar: 200 nm.
The number of cells containing eADF4(C16) particles was reduced from 7.8% to 5.4% after 6 h and from 19% to 8.5% after 24 h in the presence of DC. Further, particles made of eADF4(C16) were the only ones being internalized by less cells in the presence of DMA after 6 h (2.4%) compared to internalization by cells in the presence of DC. After 24 h of incubation, the number of cells containing eADF4(C16) particles in the presence of DMA (7.7%) was again similar to that of cells in the presence of DC. The number of cells containing eADF4(C16) particles was reduced from 7.8% to 5.4% after 6 h and from 19% to 8.5% after 24 h in the presence of DC. Further, particles made of eADF4(C16) were the only ones being internalized by less cells in the presence of DMA after 6 h (2.4%) compared to internalization by cells in the presence of DC. After 24 h of incubation, the number of cells containing eADF4(C16) particles in the presence of DMA (7.7%) was again similar to that of cells in the presence of DC.
eADF4(κ16) particle internalization was severely inhibited with DC after 6 h (27.3%) and 24 h (47.3%) whereas in the presence of DMA the internalization was less inhibited after 6 h (44%) and 24 h (73%). Accordingly, numbers of cells with blend, Tat-eADF4(C16), eADF4(C16)R8G or eADF4(C16)RGD particles decreased moderately in the presence of DMA in comparison to that in the presence of DC (Table 4) indicating that macropinocytosis plays a minor and clathrin-mediated endocytosis a major role in silk particle uptake in the used experimental setup.
Generally, three different groups can be identified which differ in particle internalization. The first group is eADF4(C16) particles with indistinguishable inhibition of internalization in the presence of both inhibitors. The second group contains Tat-eADF4(C16), eADF4(C16)RGD, and blend particles with a decreased cellular uptake in the presence of DC and a slightly less decreased uptake in the presence of DMA indicating that clathrin-mediated endocytosis is the main route of particle uptake with macropinocytosis playing a medium role. Unexpectedly, macropinocytosis played a more important role in case of eADF4(C16)RGD, despite most well-known receptors involved in receptor-mediated endocytosis (e.g. LDL receptor73) being internalized via clathrin-mediated endocytosis. Here, the amino acid sequence of the RGD peptide (GRGDSP) is optimized for the recognition by α5β1- and αvβ3-integrin.49,74 These integrin receptors are internalized by clathrin-dependent and –independent as well as caveolin-mediated endocytosis75–80 which would explain the involvement of marcopinocytosis in eADF4(C16)RGD particle internalization. The third group represents eADF4(κ16) and eADF4(C16)R8G particles which were internalized by most cells. Here, uptake is severely inhibited in the presence of DC, whereas inhibition of uptake is only moderate in the presence of DMA, indicating that here macropinocytosis only plays a minor role.
The fact that eADF4(κ16) and eADF4(C16)R8G internalization is higher than that of other modified particles (Fig. 3) makes them promising candidates for drug delivery vehicles.
A new route for producing spider silk particles has been established using the ionic liquid EMiM[acetate] as a starting solvent. Particles made therefrom show small diameters and are quite homogenous with a narrow particle size distribution. Beneath previously employed engineered spider silk proteins several variants with different (cell penetrating) peptide tags were used to produce particles. The tags and blending of proteins had no influence on particle formation but on the electrophoretic mobility, zeta potential and therefore on the colloidal stability. Interestingly, the uptake efficiency of spider silk particles by HeLa cells was highest in the presence of a poly-arginine tag (zeta potential −17.1 mV) or when using the polycationic mutant (without tag) eADF4(κ16) (zeta potential 13.2 mV) in which all naturally occurring glutamic acid residues have been replaced by lysine ones. Both the number of cells containing spider silk particles as well as the number of internalized particles was increased (Fig. 3B). Uptake mostly occurred through clathrin-mediated endocytosis for all used spider silk particles as determined by using dansylcadaverine. In combination with the recently reported encapsulation efficiency of low molecular weight drugs, low molecular weight proteins or even nucleic acids by eADF4(κ16) particles,50 engineered silk particles show high potential as novel drug delivery systems.
We gratefully thank Nicolas Helfricht for the assistance with zeta potential measurements, Jasmin Schmidt for help/discussion on colloidal stability, Marino Zerial and Undine Schubert for experimental help and inspiring discussion, Johannes Diehl and Andreas Schmidt for fermentation of eADF4(C16)R8G, eADF4(C16)RGD and eADF4(κ16), and Stefanie Wohlrab, Martin Humenik, Christian Borkner and Eileen Lintz for fruitful discussions and comments on the manuscript.
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Salamanca shopping centers online – database of shopping areas in Salamanca (Guanajuato, Mexico). Information about shopping centers, malls, factory outlet locations in Salamanca (Guanajuato).
Select Salamanca shopping areas from the list. All Salamanca (Guanajuato) shopping centers, malls are displayed on the map.


Samsung is looking to differentiate its smartphones by launching a foldable phone this year.
Samsung may be facing a lot of internal crisis that led to the chaebol replacing all of its current CEOs last quarter, but it certainly isn't affecting the company's performance. The South Korean manufacturer posted its Q4 2017 results, and once again things are looking great.
Samsung recorded an overall revenue of $61.5 billion (65.98 trillion won) with an operating profit of a staggering $14.13 billion (15.15 trillion won). That's a year-on-year increase of 64%, making last quarter Samsung's most profitable Q4 to date.
In fact, Samsung has made of habit of breaking records all through 2017. The company recorded profits of $8.8 billion in Q1 2017, $12.5 billion in Q2, and $13.8 billion in Q3. Cumulatively, Samsung's full-year revenues stand at $224 billion (239.58 trillion won) with overall operating profit at $50 billion (53.65 trillion won).
The mobile division saw a decline in overall shipments on account of "lineup optimization of low-end models," but sales of the Galaxy Note 8 were up from the previous quarter. Samsung is projecting an increase in revenue going into Q1 2018 following the launch of the Galaxy S9.
Samsung will continue its efforts to differentiate its smartphones by adopting cutting-edge technologies, such as foldable OLED displays.
The mobile division hasn't been the growth driver for Samsung for a few quarters now, with a bulk of the revenues coming from the lucrative memory and display businesses. Samsung once again noted strong orders for high-performance DRAM and NAND modules for servers and mobile storage.
Similarly, the display unit saw increased demand for OLED panels for "premium smartphones" (Samsung makes the panels for the iPhone X), with the manufacturer projecting that OLED tech will be the "mainstream panel in the smartphone industry" in 2018.
Samsung also saw increased revenue in the TV business on the back of strong sales of "ultra large-size and QLED" models. Samsung's System LSI and Foundry unit witnessed a growth decline, but the company is forecasting an uptick following increased demand of image sensors for flagship devices and application processors.
The foundry is also expected to kick off a "risk production" of a 7nm chipset later this year, and while it will be a few years before we see a consumer-ready chipset based on the 7nm node, Samsung is laying the groundwork for that eventuality.
In short, Samsung made a ton of money last year, and it doesn't look like that'll change this year.


text:
Q: How can I easily convert 139.29.0.0 to 139.029.000.000 at sql? How can I easily convert 139.29.0.0 to 139.029.000.000 at sql?

A: There are different approaches.  One is to split the string into four numbers and then reformat them.
Another approach just uses regular expressions.  The following pads all the numbers with three zeros and then takes the last three digits before each '.' or the end of the string:
select regexp_replace(regexp_replace(ip, '([0-9]+)', '000\1'), '[0-9]*([0-9]{3}([.]|$))', '\1')
from (select '139.29.0.0' as ip from dual) x

A: One option would be splitting by the dots, padding leading zeroes upto the 3 precision and then aggregating back such as
 SELECT LISTAGG( LPAD( REGEXP_SUBSTR(n,'[^.]+',1,level), 3, '0'), '.' ) WITHIN GROUP (ORDER BY level) AS IP
   FROM t
CONNECT BY level <= REGEXP_COUNT(n,'.')+1
    AND PRIOR SYS_GUID() IS NOT NULL
    AND PRIOR n = n
  GROUP BY n

Demo

redpajama_set_name: RedPajamaStackExchange


text:
Way back in 1998, the Ministry of Defence decided it needed new aircraft carriers and announced a competition amongst defence contractors. In 2003, they announced a winner, and in 2007 they signed a contract worth £3.9 billion for two vessels. As of mid-2011 they are expected to cost £5 billion (widely regarded as a gross underestimate) and the first carrier will not enter service until 2020. It will not have any aircraft. When the second carrier is ready for service, the first will be sold or moth-balled. The carriers will be 932 feet long, and will displace 65,600 metric tons.
Five days ago, the US Navy announced the name of a new aircraft carrier it was building, the USS John F Kennedy. Construction had already begun in early 2011 and it is to enter service in 2018. It will be longer (1092 feet) and heavier (101,600 tons displacement) than the Royal Navy carriers, will carry 75 aircraft, and cost an estimated $10.2 billion. The US Navy currently has eleven carriers.
Today, P&O Cruises announced they are to build a new luxury cruise liner. It too will be longer (1082 feet) and substantially heavier (154,407 tons gross) than the Royal Navy carriers, will carry the same number of aircraft as HMS Queen Elizabeth (ie none), will be in service in 2015, and will cost £500 million.
So private enterprise can build a bigger, better ship at a fraction of the price and have it at sea sooner. If we had given P&O the job at the outset we'd have two carriers off Libya right now making a useful contribution to our campaign, and have a lot more money in the coffers.
The Royal Navy's new luxury cruise liner
This entry was posted in British Politics, The Military and tagged HMS Prince of Wales, HMS Queen Elizabeth, P&O Cruises, Strategic Defence and Security Review, USS Gerald R Ford, USS John F Kennedy by Mark Griffin. Bookmark the permalink.


text:
Partly cloudy skies this evening. Increasing clouds with periods of showers late. Low 44F. Winds SSW at 10 to 15 mph. Chance of rain 40%..
Partly cloudy skies this evening. Increasing clouds with periods of showers late. Low 44F. Winds SSW at 10 to 15 mph. Chance of rain 40%.
Gov. JB Pritzker signed legislation Tuesday redrawing the state's congressional district maps.
Contributed photo
New congressional maps signed into law
By PETER HANCOCK Capitol News Illinois
Terra Temple
SPRINGFIELD — Gov. JB Pritzker on Tuesday, Nov. 23, signed legislation redrawing the state's congressional district maps, saying they reflect Illinois' diversity and preserve minority representation.
"These maps align with the landmark Voting Rights Act and will ensure all communities are equitably represented in our congressional delegation," Pritzker said in a statement.
Due to the state's declining population, Illinois will have only 17 congressional seats after the 2022 elections, one fewer than it currently has.
Because most of the state's population loss occurred in southern Illinois, the new maps combine what are currently the 12th and 15th Districts, held by Republican Reps. Mike Bost and Mary Miller, respectively, into a new 12th District that covers most of the southern one-third of the state.
Miller, however, has indicated she might run in the newly-drawn 15th District, which stretches from west-central Illinois eastward across the state, curling around the city of Champaign and stretching back west and south to an area just west of Collinsville.
It also creates a new 13th District stretching from the Metro East region across a narrow strip of land through Springfield and Decatur, to Champaign.
In the Chicago metropolitan area, the maps create a new largely-Latino 3rd District that currently has no incumbent while also putting Democratic Rep. Marie Newman's residence in the same district as fellow-Democratic Rep. Jesús "Chuy" Garcia.
Newman, however, has indicated she intends to run in the new 6th District where she would face Democratic Rep. Sean Casten in a primary.
Elsewhere, the new maps link Rockford, the Quad Cities, Galesburg, Macomb and Bloomington into one large C-shaped district.
Analysts at the Princeton Gerrymandering Project gave the new maps an overall grade of F in the categories of partisan fairness, competitiveness and compactness. They estimate the maps create 14 likely Democratic districts and three likely Republican districts.
The Illinois delegation is currently split between 13 Democrats and five Republicans.
The political reform advocacy group CHANGE Illinois, which has advocated for an independent redistricting commission, also harshly criticized the new maps, saying it was designed to produce "predetermined winners and losers in nearly all 17 districts."
"The map is undemocratic and leaves all voters without choices, undermining the very elections that are supposed to allow voters to hold officials accountable," the organization said in a statement.
Pritzker, however, said the maps align with the federal Voting Rights Act of 1965, which prohibits practices and procedures that discriminate on the basis of race, color or membership in a recognized language minority.
He said they also align with the Illinois Voting Rights Act, which requires redistricting plans to preserve clusters of minority voting groups that are large enough and cohesive enough to exert collective electoral power.
Pritzker's signing of the congressional maps comes less than two weeks before a three-judge federal court panel will hear oral arguments in three separate lawsuits challenging the new legislative maps that Democrats pushed through in August and Pritzker signed into law in September.
Plaintiffs in those suits include Republican leaders in the General Assembly; a group of Latino voters in the Chicago area represented by the Mexican American Legal Defense and Educational Fund, or MALDEF; and a group of civil rights organizations that include the East St. Louis Branch of the NAACP, the Illinois State Conference of the NAACP and the United Congress of Community and Religious Organizations, or UCCRO.
Those plaintiffs allege the new legislative maps reduce minority representation by breaking up Latino communities in the Chicago area and Black communities in the Metro East region.
Arguments in those cases are scheduled to begin Tuesday, Dec. 7.
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Caldwell County Schools announces NTI days due to increased COVID-19 cases
Illinois continues to lose population
Miss Metropolis competition set for Jan. 16
Kentucky surpasses 1 million COVID-19 cases


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On June 15, Shanghai hosts IPCOC China 2018, one of the largest intellectual property conferences in the country, with the participation of SÉRVULO.
Intellectual Property Professionals and representatives of relevant organizations with extensive experience in intellectual property rights from China and other parts of the globe will gather in Shanghai to discuss international operations in the area of ??intellectual property, namely, protection of industrial property rights, experience in operations and value generation throughout the IP value chain. The main objective is to put Portugal on the map as a promising source of IP, also boosting high-level business cooperation between Chinese and Portuguese companies.
International companies active in the IP sector will be present, including the world's first online auction company, Ocean Tomo (USA), the Weitzman Institute (Israel) and the members of the global CATHAY IP network, created to assist Chinese companies in the international matters related to intellectual property as well as western companies in China. João Saúde, SÉRVULO's liaison partner with the Cathay Associates network, will be a speaker at the conference.


Join us in the Sanborn Library for poetry readings with 2018 Poet in Residence at the Frost Place, Nicole Homer, and Sebastian Matthews of the Vermont Studio Center.
Nicole Homer is the author of the poetry collection, Pecking Order, published by Write Bloody Press, a finalist for the 2018 Paterson Poetry Prize. Her work has appeared in numerous journals and collections. A The Watering Hole graduate fellow and Callaloo fellow, Nicole Homer serves as an editor and contributor at BlackNerdProblems, and as faculty at the Pink Door Writing Retreat for Women and Gender Non-conforming Writers of Color. She is a full-time faculty member at Mercer County Community College in NJ. Aside from teaching and writing for publication, Ms. Homer is a performance poet.
Sebastian Matthews is the author of three books of poetry including Beginner's Guide to a Head-on Collision and the memoir, In My Father's Footsteps, an examination of his life growing up with poet William Matthews. Along with Stanley Plumly, Matthews is the co-editor of three collections. His poetry and prose have appeared in many journals. He is currently working on a graphic novel series and a collection of personal essays. Matthews serves as Chair on the Board of Trustees for the Vermont Studio Center and as a member on the Advisory Board for Callaloo.
Free and open to the public. This event is sponsored by The Department of English & Creative Writing. Refreshements will be served.
The Norwich Bookstore will have books by both poets for purchase and autographing.
Nicole Homer's first full-length poetry collection, Pecking Order, is an unflinching look at how race and gender politics play out in the domestic sphere. Homer challenges the notion of family by forcing the reader to examine how race, race performance, and colorism impact motherhood immediately and from generation to generation.
Beginner's Guide to a Head-on Collision offers the deeply moving poetic memoir of Sebastian Matthews's life in the years after the car accident that devastated him and his wife and son.
This clear-eyed, often wryly funny memoir pays homage to a charismatic father as the son struggles to step out from his considerable shadow. In examining his father's death (and life), Sebastian Matthews explores his own chaotic past. A child of divorce, he was shuttled throughout his boyhood between parents and many geographies.


I am a photography educator, photographer and aspiring photo editor in Peterborough, Ont. I am a graduate of the Photojournalism Program at Loyalist College.
Photo by : Anica James.
Born in Halifax, Nova Scotia.


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The future of theatre? Geoff Mills reviews Curious Directive's interrogatory show combining live performance with VR technology.
A sense of the rehearsal room.
A chaotic sprint through history.
The dark side of panto.


That's why we like to turn up on the doorstep, with a backpack of books, two little stools, and a pair of volunteers who know that words take you places.
Our volunteers don't just read stories; they do the silly voices, handpick the books, and give special recommendations. By making it fun first, we get to watch children transform into budding readers. We love when parents get stuck in with the sessions too and encourage them to get involved in their children's education.
If this sounds like the role for you, these are the basics. We run projects on Monday, Tuesday and Thursday afternoons in estates across Hammersmith and Fulham.
In Hammersmith and Fulham, projects start at 4.30pm and finish at 7.00pm.
Volunteering with us is a weekly commitment. If that isn't feasible for you at the moment, we also have a Stand in volunteer option! They fill in for regular readers when they're away. Stand in volunteers only cover reading sessions as and when they're available and so don't need to make a weekly commitment. We always need stand in volunteers, our projects wouldn't run without them!


It's April 2015 and the first race of the season, The Hot Chocolate 15K®! This was the first and only 15K (9.3 miles) I've done but it is great warm up before Broad Street®. This was super exciting because it was the first huge TIUphilly meet up! So many from the group ran either the 5k or 15k. The race started and finished at the Art Museum Steps, making it a great spot to meet and for a photo shoot :).
The Hot Chocolate is an EXPERIENCE! From the crowds, to the race decorations along the course and at the starting/finish lines, to the chocolate fondue at the finish line to charity giving back to the Ronald McDonald House. And I mean, who doesn't love chocolate. The only downfall is that only 15k runners got medals and the 5k runners did not. The rest of the swag like the hoodie is sick and you know I love coffee so the travel mug was perfect for me.
I was stoked that so many TIUgirls were running, especially ones that I have created friendships over Instagram. It was a pretty nice day weather-wise and the course was one that I was beginning to get accustomed to. The 5k girls went about 45 minutes prior and we were able to cheer them on before getting in the corrals. The Hot Chocolate was out and back course so it was fun to look for the girls during the race. I even heard other girls scream "Tone It Up" and gave me an extra push! There was a lot of support from the crowds throughout the course.
We all waited for each other at the finish line and we all finished strong. So proud of all the girls! I found out later there were more Tone It Up girls that ran that didn't meet up with us. We got out pictures with our medals after getting the finisher chocolate bowl (above pic). It was filled with chocolate fondue, cup of hot chocolate, banana, marshmallows, and more chocolate! I tried to eat a little bit but wasn't in the mood but brought it home with me. The finisher mug makes a great holder for hummus and veggies :). A bunch of us decided to go to Fare for brunch to celebrate!
I finished in 1 hour 16 minutes and 58 seconds averaging about 8:12 per mile. My best mile pace still to this date!
Brunch was fun and almost better than the race. It's nice to hang out and catch up with friends face to face instead of always through Instagram. We had mimosas and tons of food. Brunch will definitely be added to all post-race plans.
I definitely recommend the Hot Chocolate 15k and would do again. It is a flat and easy course and a great warm up to longer distance racing like Broad Street 10-miler or half marathon. The Hot Chocolate Run is done in several cities and throughout the year, across the country, so go check out to see what's near you.
What is your favorite go to post-race meal?


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