[ Back to EurekAlert! ] Public release date: 10-Feb-2011
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Contact: Elisabeth Lyons
Cell Press
Squid pheromone sparks extreme aggression on contact
The researchers believe that the findings represent the first detailed evidence of an aggression-inducing contact pheromone in any aquatic animal
When male squid come into contact with a chemical found on the outside of eggs laid by females, they instantly go from swimming along calmly and minding their own business to a state of extreme aggression, according to a new report published online on February 10 in Current Biology, a Cell Press publication. After just a touch of an egg, males will often fight vigorously with other males in an attempt to gain preferred access to mates, even when females aren't around.
"The identification of this pheromone as a key component of this signaling system is highly unusual because the male squids need only to contact these protein molecules to initiate the complex cascade of behaviors that we term aggressive fighting," said Roger Hanlon of the Marine Biological Laboratory at Woods Hole.
That's particularly notable because aggression is generally thought to be a rather complex process, involving some combination of neural, hormonal, physiological, and psychological stimuli. "Here we find what appears to be a strong and seemingly direct stimulus from certain protein molecules," Hanlon says.
Squid are highly advanced marine invertebrates with a complex mating system rivaling that of vertebrates. The loliginid squid that were the focus of the current study live for about a year, with most mating and egg laying occurring in the spring, when the squids migrate from deeper offshore waters to shallower waters along the coast from North Carolina to southern Maine. Females typically mate multiple times, and males compete fiercely for the opportunity to mate. When males see eggs on the seafloor, they will typically approach and, upon touching them, immediately escalate into intense physical fighting with any nearby males.
Hanlon and his colleagues have now traced that reaction to a single protein pheromone that is produced in the female reproductive tract and embedded in the outer surface of the egg capsules. In controlled behavioral experiments, the researchers found that males would react aggressively just as they do upon touching an egg after being presented with the purified form of the protein, known as Loligo β-microseminoprotein.
The laboratory experiments show that whichever male touches the eggs first becomes aggressive faster than those that reach the eggs later. That earlier aggression leads those males to achieve greater dominance. They also win most (but not all) of the matings and most (but not all) of the fertilizations, Hanlon says.
Interestingly, the microseminoprotein under study belongs to a family of proteins found in vertebrates including humans, Hanlon says. The proteins are generally found in reproductive glands and are at high levels in human and mouse seminal fluid.
"The functions of microseminoproteins in vertebrates have not been determined, but our findings in squids may inspire other researchers to consider similar functions in higher vertebrates," he says.


Diary Study is more of a qualitative study and is conducted over a long period of time by placing a "diary" in consumers' homes. The consumers are then requested to record their observations, experiences while using the product, their activities (what to record is determined by the area of interest).
When to use: Diary Study is a very effective tool used to determine in-home consumption patterns of consumables such as food items, home care items etc. this tool can be used to determine habits, usage patterns, purchase patterns, any changes in consumers' behaviours. For example, if one were to observe the consumers' interaction with Cooking Oil. We will place the diary and ask the consumers to note following:
 1. Quantity used every time they cook a meal
 2. What price they bought at
 3. What quantity was bought
 4. From where did they buy
 5. Do they use different oils for different foods
The study is effective only if it is done for a longer period.
 1. Gives a good understanding on consumers' interaction with a particular brand or household item
 2. We can study multiple categories at the same time
 1. Since it is self-reported study, the behavior is mostly claimed
 2. Consumer may or may not fill the diary immediately and hence may fill diary based on what they may recall. This sometimes may lead to inaccurate data
 1. Panelists need to be trained well before the study is initiated


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What's in this Guide
This guide will help you understand the purpose of a technical report and its role in engineering research. You will also find suggested starting points for researching technical reports and what you need to know to find them in the UW Libraries or elsewhere.
What Are Technical Reports
Technical reports are publications published to convey results of research usually funded by government or corporate bodies. When the government performs or sponsors research, they may require that a report of the research be published as a way to maintain public disclosure. Technical reports are most familiar to engineers, geologists, and physicists, but are usually not peer-reviewed. They are generally published as numbered series bearing the acronym of the issuing agency, the series code, and an accession number. For more information on the history of technical reports, the Science Reference Services of the Library of Congress has a useful overview here.
Recognizing Technical Reports:
Often times, you can identify a technical report from its citation or reference. Recognizing a technical report will help you determine where to look for the report. In particular, a technical report citation will include a report number and will probably not have journal or publisher information.
Technical reports can be divided into three general categories:
- Non-Governmental Reportsthese are published by engineering societies, such as AIAA
(American Institute of Aeronautical and Astronautics), IEEE
(Institute of Electrical and Electronics Engineers), or SAE (Society of Automotive
Academic Departments also publish technical reportsrun an Author search in the Libraries Catalog for: University Of Washington Dept Of Civil Engineering.
- Governmental Reportsthe research conducted in these reports has been wholly or partly sponsored by the United States or an international government body. All agencies of the U.S. Federal and State Government issue reports for example: DOE (Dept. of Energy), NASA (National Aeronautics and Astronautics), DOT (Dept. of Transportation), DOD (Department of Defense).
- Computer Science Technical Reports - these are also mostly from Computer Science and Engineering departments at various universities. Many of these are freely available online.
Civil & Environmental Engineering, Electrical Engineering
Aeronautics & Astronautics, Industrial & Systems Engineering, Mechanical Engineering
Chemical Engineering, Materials Science & Engineering
Computer Science & Engineering, Human Centered Design & Engineering

source: HuggingFaceFW/fineweb-edu


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Date of this Version
Surveys in the Elkhorn River Basin between 1972 and 1994 documented a unionid fauna of 28 taxa. Two additional taxa were documented by museum records, bringing the total to 30 confirmed for the region. In recent collections only eleven species were found as live specimens or fresh shells, suggesting the possible loss of as much as 63% of the documented fauna of the Basin. Biological diversity was once greatest in the eastern portion of the Basin, reflecting the greater variety of habitats in this region. At present, the greatest diversity appears to be found in the western portion. This reversal of biologic diversity probably reflects the extent of habitat degradation in the eastern portion. Arcidens confragosus, Lampsilis teres f. teres, and Obovaria olivaria are newly reported for Nebraska.


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Free E-booklet on Happiness and Wealth
"Seven Steps to Becoming a Happier, Wealthier Practice Owner" is a free 14-page booklet that describes the seven steps you, and everyone in the world, must take to achieve wealth and happiness. None of the seven steps involve mechanical changes, such as buying a piece of equipment or implementing a type of procedure. The seven steps are personal.
Included in the booklet:
- How to take better control of yourself and your practice
- How the right goals will dramatically improve your energy and happiness
- Ten methods for removing the barriers to your goals that work every time
- Ten traps that stop you from taking action and how to stop setting them for yourself
- How to take better advantage of opportunities that are in front of you, right now

source: openbmb/Ultra-FineWeb


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The following documents describe write operations:
- Write Operations Overview
- Provides an overview of MongoDB's data insertion and modification operations, including aspects of the syntax, and behavior.
- Write Concern
- Describes the kind of guarantee MongoDB provides when reporting on the success of a write operation.
- Atomicity and Transactions
- Describes write operation atomicity in MongoDB.
- Distributed Write Operations
- Describes how MongoDB directs write operations on sharded clusters and replica sets and the performance characteristics of these operations.
- Write Operation Performance
- Introduces the performance constraints and factors for writing data to MongoDB deployments.
- Bulk Write Operations
- Provides an overview of MongoDB's bulk write operations.
- Introduces the storage allocation strategies available for MongoDB collections.


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||This article needs additional citations for verification. (December 2007)|
A hole punch (known also as a holing pincer, hole puncher, hole maker, or rarely perforator, or paper puncher) is a common office tool that is used to create holes in sheets of paper, often for the purpose of collecting the sheets in a binder or folder. A leather punch, slightly different from one designed for paper, is used for leather goods.
The origins of the hole punch date back to Germany via Matthias Theel, where two early patents for a device designed to "punch holes in paper" have since been discovered. Friedrich Soennecken made his patent on November 14, 1886, for his Papierlocher für Sammelmappen.
A typical hole punch, whether a single or multiple hole punch, has a long lever which is used to push a bladed cylinder straight through a number of sheets of paper. As the vertical travel distance of the cylinder is only a few millimeters, it can be positioned within a centimeter of the lever fulcrum. For low volume hole punches, the resulting lever need not be more than 8 cm for sufficient force.
Two paper guides are needed to line up the paper: one opposite where the paper is inserted, to set the margin distance, and one on an adjacent side.
Hole punches for industrial volumes (hundreds of sheets) feature very long lever arms, but function identically.
Another mechanism uses hollowed drills which are lowered by a screwing action into the paper. The paper is cut and forced up into the shaft of the drill to be later discarded as tightly packed columns. This method allows a small machine to cut industrial volumes of paper with little effort.
The most common standard for the dimensions and location of filing holes punched in paper is International Standard ISO 838. Two holes with a diameter of 6±0.5 mm are punched into the paper. The centers of these holes are 80±0.5 mm apart and have a distance of 12±1 mm to the nearest edge of the paper. The holes are located symmetrically in relation to the axis of the sheet or document.
Any paper format that is at least 100 mm high (e.g., ISO A7 and larger) can be filed using this system. A printed document with a margin of 20–25 mm will accommodate ISO 838 filing holes.
4-hole extension ("888")
A four-hole extension is also commonly used. The two middle holes are punched in accordance with ISO 838, and so paper punched with the four holes can be filed in binders that are consistent with ISO 838. The two additional holes are located 80 mm above and below these. The use of two additional holes provides more stability. This extension is sometimes referred to as the "888" system, because of the three 8-cm gaps between the holes. Some 2-hole punches have an "888" marking on their paper guide, to assist punching all four holes into A4 paper.
For US Legal Size paper format (8-1/2" x 14" or 216x355 mm) traditionally 4 holes has been used in the past and still in use today but not as common as it sibling the standard 3 holes (see below). The 4 holes are preferred due to the extra long length of 14" side of the paper where the 4 holes would be placed. Binders with 4-rings gives the paper a better support in the binder. Were the documents only punched with 3 holes it will with time create sacking of the paper at the top part of the binder above the top ring. The 4 holes are positioned symmetrically 3.5" (89 mm) apart (center to center of each hole)
In regions that use the U.S. "Letter" paper format (8.5" x 11" or 216×279 mm; United States, Canada, and in part Mexico and the Philippines), a three-hole standard is widely used. The holes are positioned symmetrically, with the centres 108 mm (4-1/4 in) apart. The diameter of the holes varies between manufacturers, with typical values being 6–8 mm (1/4 to 5/16 inch). (The 5/16 value is most commonly used, as it allows for more variation in both ring binder and paper punching.) The distance of the hole center to the paper edge also varies, with 12 mm (1/2 inch) being a typical value. Unlike ISO 838, this 3-hole system appears to have no well-established exact specification. It can only be applied to paper formats that are at least 240 mm high.
Another standard also occasionally used in the United States is a filebinder system. Its two holes are positioned symmetrically, with the centres 70 mm (2-3/4 inch) apart.
In Sweden, a four-hole national standard is almost exclusively used. The centres of the holes are 21mm, 70mm and 21 mm apart. The guides help keep the paper in a straight line.
The official name of this four-hole system is triohålning since it was adapted to the "Trio binder" which was awarded Swedish patent in 1890. The binder's inventor Andreas Tengwall supposedly named it after a consortium consisting of himself and two companions, i.e., a trio.
According to Shaugho Punchers Inc., the ideal 1 Hole Punch places the centre of the hole punched at 1.0 cm in from the left of a page and 4.0 cm down from the top of a page. According to Killeen Co., the punched hole should between 0.9 cm and 1.1 cm from the left hand side of a page and between 3.9 cm and 4.1 cm from the top of a page.
Uses of hole punches
Single hole punches
Single hole punches are often used to punch tickets, which indicates its credit has been used, and to make confetti when creating scrapbooks and other paper crafts. For applications needing a variety of hole shapes, a ticket punch may be used. A single hole punch differs from a ticket punch in having a shorter reach and no choice of hole shape.
In the United States, single hole punches are often used to punch holes through playing cards, rendering them "used." This helps cut down on cheating by eliminating any cards that may have been tainted by players. Paper drilling is also popular for this purpose.
A related office tool is the eyelet punch. This is a single-hole punch which also presses a metal fastening loop around the hole. It is used to permanently secure a few sheets of paper together which must not be separated or modified.
Multiple hole punches
Multiple hole punches typically make between one and eight holes at one time, the placement of which matches the spacing of the rings in a binder. For example the filofax system uses six holes in two groups of three.
With a few exceptions, two-hole and four-hole punches consistent with ISO 838 are the norm.
In the United States the three-hole punch is most common. Less frequently seen is the two-hole filebinder punch.
There are office models available for the perforation of 1 to 150 sheets of paper, and industrial models for up to 470 sheets. Most multiple-hole and many single-hole punches accumulate the waste paper circles (chads) in a chamber, which must be periodically emptied in order to facilitate the continued operation of the punch.
Paper drills are machines similar to a drill press that use hollow drill bits to drill through stacks of paper. The hollow bit design allows the chads to be ejected during drilling. Paper drills in the United States are most commonly either single-hole or three-hole in construction.
- br-online (German)
- "Appletonideas Punch Resources". Retrieved 2013-02-12.
- "Paper Punch & Cutter Resources". Retrieved 2009-08-12.
|Wikimedia Commons has media related to: Hole punchers|


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bathtub is more than just a simple compressor: it does multi-band compression, multi-layer parallel compression, series compression, mid/side compression, Left/Right compression, RMS/Peak detection, side-chaining, look-ahead, limiting & maximizing and has comprehensive metering and clip counting.
bathtub is really two flexible and configurable stereo compressors that can be routed to be in series or parallel, can be fed the input signal split into high/low frequencies or full band, and can perform as different styles of compressor, limiter or maximizer to produce a range of flavours and effects. The metering shows you visually what is happening too, so you can see how much compression and gain you are getting.
- 2 Band multi-function compressor with comprehensive metering.
- Flexible controls allow use as a compressor, limiter or maximiser.
- Can be used as a single band compressor, dual band compressor, dual parallel compressor or dual series compressor.
- 2 bands can be split high / low freq or full spectrum.
- 2 bands can be in parallel or series.
- Fully adjustable frequency split point with adjustable overlap/gap of bands.
- Each band has a full set of independent compression controls for different compression flavours in each.
- Each band has stereo balance for independent Left and Right channel compression.
- Each band has mid/side stereo narrow/width control, which can be used to narrow the low frequency and spread the high, or have independent mid/side compression.
- Either or both bands can use sidechaining to drive the compressor from an external signal.
- Either or both bands can be muted to help with sound design or save CPU in single band mode.
- Attack / Release curve can be linear or non-linear.
- Stereo input detection can be linked or unlinked.
- Input detection can be filtered to reduce distortion at short release times.
- Input detection can be stereo average or max level.
- Input detection can be Peak or RMS level with adjustable window.
- Optional soft limit at final output.
- Look-ahead defined by user in ms.
- Wet/Dry mix control allows blending of dry uncompressed signal for NY style parallel compression.
- Metering for each band and combined output, covers stereo input, output and gain, gain reduction and clip indicator/counter, with adjustable sensitivity. All meters show actual and peak levels.


Critical thinking, Communication, Collaboration, and Creativity.
Berkshire Museum's education programs are designed to encourage students to think critically, problem-solve, and work side-by-side with their peers while taking full advantage of the Museum's unique collection, one that combines natural science, art and history. The emphasis is always on creativity and innovative thinking.


At Xylotek, we are always excited by the potential of lamella structures and the magic of reciprocal systems where long spans can be achieved using small elements. We've worked on many lamella structures, both freeform and geometrically more restrained, including pioneering digitally-fabricated projects.
Lamella Structures
Lamella structures are formed of discrete structural elements that combine in two-way spanning grid systems. By arranging members in a grid pattern, long freeform spans can be achieved from relatively short members, and complex forms from geometrically simple components.
Reciprocal grids
Reciprocal systems enable structural continuity within lamella structures through patterns in which beams mutually support each other. This is achieved by having elements typically twice the length of grid cell dimension and alternating the elements so that each one is mutually supported by its neighbours – so that the elements ends are carried at the mid-points of its neighbours. Reciprocal frames can similarly be created with a circular loop of mutual support, such as used on the Lake Bunyonyi theatre project.
Nexorade structures
A more complex variant of the reciprocal structure is the 'nexorade' in which elements meet eccentrically at connection points, forming pinwheel-like arrangements within the overall structure. Varying offsets of each connection can introduce curvatures into the grid, allowing freeform shapes to be created from relatively simple elements.
Zollinger roof system
The reciprocal logic has historic precedent – as sketched by da Vinci and developed by Friedrich Zollinger in the 1920s into a roof construction system in which short elements are arranged in a diamond pattern as a regular reciprocal grid. Typically, the Zollinger system uses standardised lamellas that are arrayed to form singly-curved surfaces in barrel-like roof configurations. The system is very strong for its weight and can be assembled with minimal lifting equipment.
Multi-axis machining
Contemporary CNC and robotic machining technologies allow the creation of different unique geometries for each element, enabling variation in element lengths and connection angles according to each member's position within the system. A particular benefit of the reciprocal pattern is that end connections do not need to transmit bending moments.


Skip to definition.
Verb: ret (retted,retting) ret
 1. Place (flax, hemp, or jute) in liquid so as to promote loosening of the fibers from the woody tissue
Derived forms: rets, retting, retted
Type of: douse, dowse, drench, soak, sop, souse
Encyclopedia: Ret


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- Proposed changes to the regulatory capital rules governing the stress testing requirements and the enhanced supplementary leverage ratio (ESLR) would tailor these rules to reflect the business activities and risk profile of large banking organizations.
- New stress buffer requirements would integrate the quantitative assessment of the Federal Reserve's CCAR and stress test rules with the regulatory capital buffer requirements.
- Modifications to the ELSR applicable to GSIBs would replace the leverage buffer with an amount based on a firm's risk-based capital surcharge; corresponding changes would be made to incorporate this new amount into the "well-capitalized" threshold applicable to Covered IDIs and to the TLAC requirements.
Federal Reserve Board (Federal Reserve) Vice Chairman for Supervision Randall Quarles has advocated tailoring the post-crisis regulations to better reflect the risk posed by individual institutions. Although the focus has primarily looked to reducing the regulatory burden of community banks, two recently proposed rules would tailor certain regulatory capital requirements for very large banking institutions and tie those requirements to the firms' business activities and risk profiles. Key features of each proposal is summarized below.
Capital and stress test requirements
The Federal Reserve has proposed to integrate the quantitative assessment of its Comprehensive Capital Analysis and Review (CCAR) with the buffer requirements in its capital rules to create "stress buffer requirements," including a "stress capital buffer" and a "stress leverage buffer." The rule would apply to bank holding companies (BHCs) with total consolidated assets of $50 billion or more and intermediate holding companies of foreign banking organizations. A firm's stress buffer requirements would be effective on October 1 of each year, and remain in effect until September 30 of the following year. As proposed, the rule would become effective on December 31, 2018 with the first stress capital buffer and stress leverage buffer requirements becoming generally effective October 1, 2019.
- Stress capital buffer: The stress capital buffer would be calculated as the difference between a firm's starting and lowest projected common equity tier 1 (CET1) ratio under the severely adverse scenario of the supervisory stress test calculated using the standardized approach, plus the firm's planned common stock dividends for each of the fourth through seventh quarters of the planning horizon (expressed as a percentage of risk-weighted assets (RWAs)). The stress capital buffer would be subject to a floor equal to 2.5 percent of RWAs.
- The stress capital buffer would replace the 2.5 percent of RWAs portion of the capital conservation buffer under the standardized approach; the advanced approach would continue to use the 2.5 percent of RWAs measure in the capital conservation buffer.
- Stress leverage buffer: The stress leverage buffer would be calculated as the difference between a firm's starting and minimum projected tier 1 leverage ratio under the severely adverse scenario of the supervisory stress test plus planned common stock dividends for each of the fourth through seventh quarters of the planning horizon (expressed as a percentage of RWAs). The stress leverage buffer requirement would replace the CCAR requirement that a firm demonstrate its ability to maintain capital levels above minimum leverage requirements on a post-stress basis. It would have no floor and would be additive to the 4 percent minimum required CET1 leverage ratio.
- CCAR changes: The proposed rule would make three adjustments to CCAR: (1) firms would be required to prefund only four quarters of planned common stock dividends; (2) a firm's balance sheet would be assumed to remain constant under stress; and (3) the 30 percent dividend payout ratio threshold for heightened supervisory scrutiny would be removed.
- Objections to stress test results: The proposed rule would eliminate the Federal Reserve's ability to object to a firm's CCAR results based on quantitative measures. A pattern of materially underperforming baseline projections for earnings, capital levels, or capital ratios may be indicative of weaknesses in the firm's capital planning and result in heightened scrutiny in the qualitative assessment.
Enhanced supplementary leverage ratio
The ESLR is applicable to U.S. global systemically important banking holding companies (GSIBs) and their Federal Reserveand OCC-regulated insured depository institutions (Covered IDIs). For these entities, the proposed changes would:
- Replace the ESLR buffer: The 2 percent leverage buffer would be replaced by a leverage buffer equal to 50 percent of a firm's GSIB risk-based capital surcharge (GSIB surcharge). The current minimum 3 percent supplementary leverage ratio requirement would not change.
- Change IDI "well-capitalized" threshold: he current "well-capitalized" threshold of 6 percent applicable to covered IDIs under the prompt corrective action framework would be changed to a threshold of 3 percent plus 50 percent of the GSIB surcharge applicable to the IDI's GSIB holding company.
- Make corresponding changes to TLAC: Calculation of the external Total Loss-Absorbing Capacity (TLAC) leverage buffer and long-term debt requirement would be amended to incorporate 50 percent of the firm's GSIB surcharge, consistent with changes to the ESLR.
Federal Reserve staff estimate the proposed stress buffer requirements would decrease the amount of capital required for non-GSIBs subject to CCAR relative to current requirements, and generally maintain or, in a few cases, increase the amount of capital required for GSIBs. With regard to the ESLR proposal, Federal Reserve and OCC staff estimate that the changes would lead to a reduction in CET1 capital requirements of approximately $400 million. Firms would continue to be expected to meet minimum capital requirements plus minimum buffer requirements to avoid limitations on capital distributions and discretionary bonus payments.
For more information, please contact Steve Arnold or Frank Manahan.


Divorce Can Significantly Impact a Person's Investment Portfolio
Many things can change for a person here in Colorado as a result of getting a divorce. One is what their investment portfolio looks like. This is because investments are among the assets that are sometimes marital assets and thus are sometimes subject to being split up between the divorcing spouses in the divorce asset division.
How specifically a divorcing couple's investments are dealt with in an asset division can have major portfolio-related impacts on both of the members of the couple. Among the things the specifics of an investment division in a divorce can impact for a divorcing individual are:
 - What investment-related decisions will be before them following the divorce.
 - How balanced their portfolio is.
 - Whether their portfolio has any particular holes in it.
 - What sorts of changes a person may want to make to their portfolio following the divorce.
Given the major changes a divorce can have on a person's investment portfolio, some find conducting a review of their portfolio helpful following a divorce.
Of course, paying attention to the portfolio-related impacts of a divorce is not only important after a divorce has occurred, but also during the divorce process. Given the impactful nature that how investments are divided in a divorce can have, it can be very important for a person to keep their long-term financial and investment goals in mind when in negotiations regarding such asset division. Given the many complicated issues that can happen during divorce property division and the major long-term impacts property division can have, a divorcing individual may want the help of a family law attorney when it comes to the issue of property division in their divorce.


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I have seen that $x^{2}+x+1$ and $x^{4}+x+1$ are irreducible over $\mathbb{Z}_2$ and I thought a polynomial of the form $x^{2^m}+x+1$ for $m\ge3$ would be irreducible too. However using WolframAlpha, my hunch was wrong. It could be factored over $\mathbb{Z}_2$. WolframAlpha could only generate the factors for $m=3,\ldots, 13$ and so far, I observed that for odd $m$, my polynomial is divisible by $x^{2}+x+1$.
I want to see how one can show that $x^{2^m}+x+1$ for $m\ge3$ is reducible.
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4 Answers 4
up vote 12 down vote accepted
I will write $\mathbb F_2$ rather than $\mathbb Z_2$; here the $\mathbb F$ stands for "finite field" and the subscript is the number of elements in the finite field. This notation is convenient when one wants to consider larger finite fields, as I will in this answer.
The polynomial $x^2 + x + 1$ splits in the field $\mathbb F_4$ with $4$ elements; its two roots are the two elements of $\mathbb F_4$ that aren't in $\mathbb F_2$. Now if $\alpha \in \mathbb F_4$ then $\alpha^4 = \alpha$. Thus if $n = 2 m + 1 $ is odd, we have that $$\alpha^{2^{2m + 1}} = (\alpha^{4^m})^2 = \alpha^2,$$ and so $$\alpha^{2^{2m+1}} + \alpha + 1 = 0.$$ Consequently each of the two roots of $x^2 + x + 1$ is also a root of $x^{2^{2m+1}} + x + 1$ as well, which explains why $x^2 + x + 1$ divides $x^{2^{2m + 1}} + x + 1.$
To handle the general case of $x^{2^n} + x + 1$ (i.e. the case when $n$ is not necessarily odd) it helps to recall some Galois theory for finite fields. The key fact is that if $\alpha$ lies in any finite extension field of $\mathbb F_2$, namely some $\mathbb F_{2^f}$ for some $f \geq 1$, then the algebraic conjugates of $\alpha$ are all of the form $\alpha, \alpha^2,\alpha^4, \ldots.$ (This list will be finite, because --- assuming I chose $f$ minimally --- then $\alpha^{2^{f-1}} \neq \alpha,$ but $\alpha^{2^f} = \alpha$, and so $\alpha$ has exactly $f$ distinct conjugates over $\mathbb F_2$.)
Now suppose that $\alpha$ satisfies $$\alpha^{2^n} + \alpha + 1 = 0.$$ Adding $\alpha + 1$ to both sides (and remembering that $ 1 = - 1$ because we in characteristic $2$) we find that $$\alpha^{2^n} = \alpha+1.$$ Hence $$\alpha^{2^{2n}} = (\alpha^{2^n})^{2^n} = (\alpha + 1)^{2^n} = \alpha^{2^n} + 1 = (\alpha +1)+1 = \alpha$$ (using the facts that $(a+b)^2 = a^2 + b^2$ and $1 + 1 = 0$, which both hold in characteristic $2$).
So we see that the "$f$" for $\alpha$ is at most $2n$, i.e. $\alpha$ has at most $2n$ distinct algebraic conjugates over $\mathbb F_2$, and so its minimal polynomial over $\mathbb F_2$ has degree at most $2n$. Since $\alpha$ is a root of $x^{2^n} + x + 1$, this minimal polynomial divides $x^{2^n} + x + 1$. If $n \geq 3$, then $2n$ is strictly less than $2^n$, and so this minimal polynomial of $\alpha$ also has degree strictly less than that of $x^{2^n} + x + 1$. Thus when $n \geq 3,$ the polynomial $x^{2^n} + x + 1$ must be reducible.
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@ Matt E: How do show that polynomial $x^2+x+1$ splits in $\mathbb{F}_4$? – boj54 Mar 21 '11 at 14:10
_USER_ For instance $x^4 - x = \prod_{u\in\mathbb F_4} (x-u) = x(x+1)(x^2+x+1) $. – Myself Mar 21 '11 at 14:19
you could make it by definition. it's irreducible over $\mathbb{F}_2[x]$ so $\mathbb{F}_4\cong\mathbb{F}_2[x]/(x^2+x+1)$ – yoyo Mar 21 '11 at 14:19
@ Myself: I got it. Thanks. – boj54 Mar 21 '11 at 21:10
_USER_: Dear boj54, This was a typo, now fixed. Regards, – Matt E Mar 22 '11 at 5:08
I would like to present a solution that is completely different from Matt E's method. The starting point is the numerical observation (which I found with PARI) that when you factor $x^{2^n} + x + 1$ in ${\mathbf F}_2[x]$ the number of irreducible factors that occur for $n = 1, 2, 3,...,11$ is $$ 1, 1, 2, 2, 4, 6, 10, 16, 30, 52, 94. $$ The striking thing about those numbers after the second one is that they are all even. The lesson here is that when you were looking at data to understand why these polynomials were usually reducible, you should not only have been looking for some "obvious" irreducible factor, but also at the number of irreducible factors. Without showing there is any one particular "obvious" irreducible factor I am going to explain why, for $n \geq 3$, $x^{2^n} + x + 1$ must have an even number of irreducible factors in ${\mathbf F}_2[x]$. That will show this polynomial is reducible in ${\mathbf F}_2[x]$, since an irreducible polynomial has only one irreducible factor.
In elementary number theory, there is a standard function which counts the parity of the number of prime factors of a positive integer. It's called the Möbius function and is defined as follows: for a positive integer $N$, $$ \mu(N) = \begin{cases} 0, & \text{ if } N \text{ has a multiple prime factor}, \\ (-1)^r, &\text{ if } N = p_1\cdots p_r \text{ where the } p_i\text{'s} \text{ are distinct primes}. \end{cases} $$ So $\mu(N) = 1$ if $N$ is a product of an even number of distinct primes (in particular, $\mu(1) = 1$ using $r = 0$) and $\mu(N) = -1$ if $N$ is a product of an odd number of distinct primes, while $\mu(N) = 0$ if there is some prime factor of $N$ appearing more than once (e.g., $\mu(12) = 0$ since 2 is a factor of 12 twice). So the Möbius function really only counts the parity of the number of prime factors of squarefree positive integers. For any prime $p$, $\mu(p) = -1$. Therefore if $\mu(N) = 1$ then $N$ is definitely not a prime number.
The catch with the Möbius function is that there's no known way to figure out what $\mu(N)$ is without essentially factoring $N$. Well, to be on the safe side, let me just say that if we know $N$ is squarefree, so $\mu(N) = \pm 1$, then figuring out whether $\mu(N)$ is $1$ or $-1$ can't be done without factoring $N$. Put simply, there is no formula for $\mu(N)$ other than its definition. (Of course, if you haven't seen the Möbius function before, then another catch is that it looks like a completely crazy function. Why is it significant? The reason is the Möbius inversion formula, in which the Möbius function plays a prominent role. One of its


.clock.colorTo: are gone.
the line toolbar.clock.pixmap: was added. the three exchanged lines from above can be erased or you can leave them in the style, it doesn't matter they have no use in this case. actually it is logical, because the components's background is no longer rendered. so there's no need for texture options or gradient colors at all.
images for menu.title.pixmap, toolbar.pixmap, toolbar.clock.pixmap, toolbar.workspace.pixmap, toolbar.iconbar.empty.pixmap, toolbar.iconbar.focused.pixmap, toolbar.iconbar.unfocused.pixmap, window.title.focus.pixmap, window.label.focus.pixmap, window.handle.focus.pixmap, window.handle.unfocus.pixmap, window.grip.focus.pixmap and window.grip.unfocus.pixmap appear as high as defined by the corresponding *.height value. those images will be stretched horizontally to the length of the part.
the image size for a button should be a 1:1 ratio with the the height/width = *.height since the image is stretched horizontally and vertically if you define *.height bigger than the button-image is. this sounds confusing the way i explain it, but if you try it should get clear. you may play around with different image sizes but believe me, it's just a pain in the ass usually.
furthermore another important thing is: in a classic style all buttons are defined through window.button.*. in a pixmap style you CAN make a image for each button and their states (focused, unfocused, pressed). you don't have to but you can. to give an example of the buttons you can style look at this:
window.shade.pixmap: shadefcs.xpm
window.shade.unfocus.pixmap: shadeufcs.xpm
window.shade.pressed.pixmap: shadepr.xpm
window.unshade.pixmap: unshadefcs.xpm
window.unshade.unfocus.pixmap: unshadeufcs.xpm
window.unshade.pressed.pixmap: unshadepr.xpm
window.menuicon.pixmap: menuiconfcs.xpm
window.menuicon.unfocus.pixmap: menuiconufcs.xpm
window.menuicon.pressed.pixmap: menuiconpr.xpm
window.close.pixmap: closefcs.xpm
window.close.unfocus.pixmap: closeufcs.xpm
window.close.pressed.pixmap: closepr.xpm
window.iconify.pixmap: minfcs.xpm
window.iconify.unfocus.pixmap: minufcs.xpm
window.iconify.pressed.pixmap: minpr.xpm
window.maximize.pixmap: maxfcs.xpm
window.maximize.unfocus.pixmap: maxufcs.xpm
window.maximize.pressed.pixmap: maxpr.xpm
window.stick.pixmap: stickufcs.xpm
window.stick.unfocus.pixmap: stickufcs.xpm
window.stick.pressed.pixmap: stickpr.xpm
window.stuck.pixmap: stuckfcs.xpm
window.stuck.unfocus.pixmap: stuckufcs.xpm
window.stuck.pressed.pixmap: stuckufcs.xpm
the syntax differs a little bit from the other parts, but again it's really simple to understand. look at the little screenshot to get a clue what the buttons are.
window.*.pixmap are the pixmaps you see on a focused window.
window.*.unfocus.pixmap are the pixmaps you see on an unfocused window.
window.*.pressed.pixmap are the images you see when you click the button.
window.stuck.* is the activated state of the stick buttton.
some other things are different from classic styles. the bullet and the selection indicator (the little thing to show what configuration options are enabled or what style is selected) can be images. furthermore those elements can have different states:
menu.submenu.pixmap:
menu.hilite.submenu.pixmap:
menu.selected.pixmap:
menu.hilite.selected.pixmap:
menu.unselected.pixmap:
menu.hilite.unselected.pixmap:
menu.selected.pixmap and menu.unselected.pixmap are selfexplanary i think (they are the selection indicators). the menu.submenu.pixmap entry simply is the well known bullet.
a size of 16x16 for the bullets and selection images seem to be most appropriate. it depents on the fontsize and the menu's bevel how much they will be streched.
the *.hilite.* calls the images that show up when the mouse comes over the line of the menu. you don't have to set them. if nothing is defined, fluxbox will use the images that are shown when not highlighted.
last update 03/08/2006


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Hitachi has successfully tested a brain-machine interface that allows users to turn power switches on and off with their mind. Relying on optical topography, a neuroimaging technique that uses near-infrared light to map blood concentration in the brain, the system can recognize the changes in brain blood flow associated with mental activity and translate those changes into voltage signals for controlling external devices. In the experiments, test subjects were able to activate the power switch of a model train by performing mental arithmetic and reciting items from memory.
The prototype brain-machine interface allows only simple control of switches, but with a better understanding of the subtle variations in blood concentrations associated with various brain activities, the signals can be refined and used to control more complex mechanical operations.
In the long term, brain-machine interface technology may help paralyzed patients become independent by empowering them to carry out actions with their minds. In the short term, Hitachi sees potential applications for this brain-machine interface in the field of cognitive rehabilitation, where it can be used as an entertaining tool for demonstrating a patientís progress.
The company hopes to make this technology commercially available in five years.


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Mercury(II) thiocyanate has been used for the determination of the chloride ions by colorimetric method.
It can be employed as a reactant for the synthesis of:
- Polymeric mercury(II) coordination complexes with various derivatives of 4,4′-bipyridine ligands via the branched tube method.
- Manganese mercury thiocyanate (MMTC), an organometallic optical single-crystal.
- Heterotrinuclear copper(II)–mercury(II)–copper(II) complexes possessing antibacterial and antifungal activities.
|mp||165 °C (dec.) (lit.)|
|density||3.71 g/mL at 25 °C (lit.)|
|cation traces||Ca: ≤50 mg/kg|
|Cd: ≤50 mg/kg|
|Co: ≤50 mg/kg|
|Cu: ≤50 mg/kg|
|Fe: ≤50 mg/kg|
|K: ≤1000 mg/kg|
|Na: ≤100 mg/kg|
|Ni: ≤50 mg/kg|
|Pb: ≤50 mg/kg|
|Zn: ≤50 mg/kg|
|reaction suitability||reagent type: catalyst|


How BIG was Noah's Ark?
Submit questions - New Articles
How big was Noah's ark? Let us start by defining a cubit. A Biblical cubit is considered the length between the elbow of an adult and their fingertip, which is calculated to being 18 U.S. inches (roughly). Quite a few scholars who study the Hebrew Bible believe a cubit was somewhere in between 17.5 to 21.5 inches long. If we conservatively assume that a cubit was 18 inches (U.S.), we can conclude that the ark was about 450 feet (U.S.) long, 75 feet (U.S.) wide, and 45 feet (U.S.) high.
The interesting thing about Noah's ark its construction was on a 1:6 ratio. Naval architecture reveals that this is the most stable ratio for an ocean-going vessel. It could have easily survived even big ocean waves and would be next to impossible to capsize. The amount of water the ship would displace, given a draught of 15 cubits, exceeds 22,000 tons.
How many animals did it carry?
How many total animals did God want carried in the ark? Many who refuse to believe in what the Bible says state that the ship's capacity would be nowhere big enough to handle the millions of different animals it was supposedly required to carry. The truth, however, is far different from the rhetoric of those who are against God and his word!
How many clean and unclean animals would Noah's Ark have to take on board? What the Bible (Leviticus 11, Deuteronomy 14) considers clean (fit for human consumption) and unclean (not fit to eat) animals is easy to identify based on the characteristics of a particular creature. For example, warm-blooded mammals that have split hooves and chews the cud is clean to eat (e.g. Bison, Cattle, Deer, Goats, Sheep, etc.). Those that do not have these characteristics are not clean and good for man (e.g. Pigs, Lions, Tigers, Boars, etc.)
What did RAINBOWS symbolize after the flood?
Why was Noah's lifespan so long?
How LONG did it take to build the ship?
What does the INSIDE of the Ark look like?
Those who are against God say that Noah had to take SEVEN pair of clean animals and SEVEN pair of the birds (Genesis 7:2-3) with him. Is this assumption true? The answer to the question is in Leviticus 11 and Deuteronomy 14. When properly understood, Noah took on seven (7) individual animals and birds (not seven pairs) of each kind that were clean. Since these types of animals would later be used for food, it would be important to have extra breeding stock. There was three pair of clean animals and clean birds plus a seventh. The seventh one was to be offered as a sacrifice at the end of the flood (Genesis 8:20). If an animal were unclean, which the vast majorities were, then only one pair came aboard the great ship.
Contrary to what many believe and what "documentaries" concerning the ark claim, the ship would have EASILY been big enough to carry all the required animals. Only air breathing, land dwelling animals would have to be placed on the ark itself (Genesis 7:22). In the book The Genesis Flood, it states that animals such as fish, starfishes, sea urchins, mussels, clams, corals, jellyfish, sponges, and many others could have survived outside Noah's ship.
The number of animals saved
Space needed for the animals
Why drown a billion people?
One honest, basic question is why was there a need for Noah's ark in the first place? What caused God, Who is the very definition of love, to take the extreme measure of DROWNING roughly one BILLION people at the same time? The Bible itself gives us the answer.
In the roughly 1,500 years from Adam's creation man had grown corrupt and brutal. The consequences of their selfishness, lust, greed and disobedience, compounded by the fact they lived exceptionally long life spans, led to a preoccupation with evil. God, who saw the cavalcade of suffering and pain man endured, with no end in sight due, mercifully ended their ongoing self-torture. Yet the Eternal was also merciful by having Noah's ark built to save a righteous man and his family so that humanity could have a new start after the flood.
Additional Study Materials
Did a race of GIANTS exist before the deluge?
Did DINOSAURS exist before the flood?
How did the deluge lead to HALLOWEEN?
© The Bible Study Site


CBC Digital Archives
Lesson Plan: For Teachers - The Notwithstanding Clause: A Classroom Debate
History, Political Science
2 lessons
To support and debate a given position on the use of the notwithstanding clause
Students will research and debate the use of the notwithstanding clause to limit rights under the Charter of Rights and Freedoms.
Lesson Plan
Before Exploring
Write the term "notwithstanding clause" on the board. Ask students if they are familiar with this section of the Charter of Rights and Freedoms. Explain to students that the notwithstanding clause allows federal or provincial governments to pass a law that violates rights and freedoms in the Charter as long as it is reviewed every five years and approved by the respective legislature. Essentially, governments can opt out of section 2 and sections 7 to 15 of the Charter.
Explain that the Quebec government passed a language law in 1977 that restricted the use of the English language, particularly on public signs and in businesses. In 1988, the law was challenged as a violation of the Charter and held to be unconstitutional by the Supreme Court of Canada. Nevertheless, the Bourassa government used the notwithstanding clause to allow the government to opt out of the Charter and enable French-language-only sign laws to prevail.
Ask students to work with a partner and discuss if Charter rights should be limited. Should there be an opt-out clause in the Charter? Share and discuss student responses.
Outline the Opportunity
Direct students to the topic Fighting Words: Bill 101 on the CBC Digital Archives website. In small groups, have students browse the clips "'French in Quebec: it's a plus,'" "Bill 101's first legal blow," "Mr. Singer goes to court" and "Bourassa's dilemma" and then conduct further research by examining the clips "The 1988 Supreme Court decision on signs,", "Defending his decision" and "Quebecers on the Supreme Court decision."
With their group members, have students take notes assessing the pros and cons of using the notwithstanding clause. They will use their notes to develop arguments for a class debate.
Select and present one of the following resolutions:
 - Be it resolved that the notwithstanding clause is a viable option to be used by federal and provincial governments to limit the application of the Charter.
 - Be it resolved that the notwithstanding clause allows for an unacceptable violation of rights and freedoms.
Assign each group either the 'for' or 'against' position, then pair up groups and have them debate the resolution in front of the class.
Assessment Tip: Download and distribute the Debate Rubric. Students can use it to guide their own preparation and later to score the debates.
Revisit and Reflect
Have students vote on which group won their respective debate. Ask: Which arguments were the most persuasive? Did your personal opinion change as a result of any of the debates?
Assessment Tip: Look for a clear summary of the pros and cons of the debated issue.
Students can write a one-page position paper to support or criticize the use of the notwithstanding clause to limit constitutional rights. They should use three arguments to support their position.
Charter of Rights and Freedoms
Download PDF
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A common reporting challenge in Excel is merging sets of data, such as combining monthly numbers for a quarterly or annual total. Adding up simple metrics is obvious, but what do you do with things like the average position or conversion rate? [Hint: you should not average or total anything that is already an average or ratio]
207,001 impressions with avg position of 35.7 + 735,462 impressions with avg position of 55.1 = 942,463 impressions with avg position of?
The Lure of the Weighted Average
Rates and averages are calculated metrics, and they are all based on a sample or 'population' of data. In the example above, an average position of 55.1 (highlighted in yellow) is based on a specific group of 735,462 impressions. The actual math behind that average position involves adding up all the individual position values and dividing by the total number of impressions:
avg position = (sum of positions) / (number of impressions)
When combining calculated metrics like these, the size of each group is important — combining a small sample into a larger sample should not affect the overall average much (it should be closer to 55.1 than to 35.7 in the example above). What we want is a "weighted" average, where the size of the sample is taken into account when the numbers are combined. Searching for a typical formula for a weighted average yields something like this — you multiply each average by a weighting factor that is calculated from the proportion of the impressions they represent, then add them together:
weighted average = avg position1 * impressions1/(impressions1+impressions2) + avg position2 * impressions2/(impressions1+impressions2)
Just describing it sounds complicated, and this formula is hard to implement, especially with large data sets. It would require looking up matching rows, then calculating the proportion or "weight", then applying that to the avg position number, and finally adding them together. That is a lot of lookups and calculations, and it could be very slow.
Simplifying the Problem, and the Solution
In situations like this, we need to restate the problem in a way that is easier (faster) to solve. Going back to the simple formula for the average, we can assume that if the average position is the sum of positions divided by the number of impressions, then the average position for the combined data should be the sum of all of the positions, divided by the number of all of the impressions:
avg position = (sum of positions1 + sum of positions2) / (impressions1 + impressions2)
It sounds a lot simpler than the formula above, and if you are good at math formula substitutions, you can actually show this will result in exactly the same number. The difference is that it involves a number we don't have in our data: the "sum of positions". But that is easy enough to calculate; since the avg position is the (sum of positions)/impressions, then we know:
sum of positions = avg position * impressions
Believe it or not, we now have a really simple way to combine our average with a few simple steps in a spreadsheet:
- append one data set to the other
- add a column calculating (avg position * impressions) called "sum of positions"
- combine duplicate rows, summing the numbers in matching rows
- calculate a new avg position = (sum of positions)/impressions
A Generic Approach
If you apply the same thinking to the click-through-rate (ctr) in a standard Google Search report, you will realize that you already have the clicks and impressions (they are default metrics) that are needed to calculate ctr (ctr = clicks/impressions). All you need to do is to append the data, combine the duplicate rows, then calculate the new ctr column from clicks/impressions.
The 'extra' step for the avg position in the first example exists because we did not start with one of the 'base' metrics behind the calculated metric — the (sum of positions). Going back to the step-by-step list, we can make it more generic:
- append one data set to the other
- if you need to combine calculated metrics (average, rate, percentage), then first break them down into their base metrics*
- combine duplicate rows, summing the numbers in every column
- recalculate the calculated metrics from the (summed) base metrics
Note: if you can, include the base metrics in your query to eliminate the need for the second step. e.g. include Bounces and Sessions in your query instead of the Bounce Rate.
Putting it into Practice
While you could do all of this manually in Excel, this kind of step-by-step math is what the Analytics Edge Core Add-in is made for, and the whole process can be automated in a couple of minutes as this video shows.
Base Metrics for Common Rates and Averages
Your first challenge is to figure out what the base metrics are for any rate or average metric you are using. You can then include those metrics in your query, or calculate them from the data you do have. Here are some of the common ones for Google Search and Google Analytics:
ctr = clicks / impressions
[avg] position = (sum of positions) / impressions
bounce rate = bounces / sessions
% new sessions = new users / sessions
avg session duration = session duration / sessions
goal conversion rate = goal completions / sessions
avg order value = revenue / sessions
ecommerce conversion rate = transactions / sessions
If you need to merge two or more sets of numbers and they include calculated metrics like averages, rates or percentages, make sure you combine them the right way. Don't be put off by complicated formulas for weighted averages – the problem, and solution, is actually quite simple.
Start with (or calculate) the base metrics, combine (sum) the duplicate rows, and recalculate the calculated measures. Simple operations for accurate reporting.


The volume of an expanding sphere is increasing at a rate of 12cubic feet per second. When the volume of the sphere is cubic feet, how fast, in square feet persecond, is the surface area increasing?
Note: ( )
(A) 8
(B) 6
(C) 8π
(E) 10
Can someone show it step by step?
I kind of remember this kind of question, but not sure if I did itright.
Get this answer with Chegg Study


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Background: Previous studies identifying patients with inflammatory bowel disease using administrative codes have yielded inconsistent results. Our objective was to develop a robust electronic medical record–based model for classification of inflammatory bowel disease leveraging the combination of codified data and information from clinical text notes using natural language processing.
Methods: Using the electronic medical records of 2 large academic centers, we created data marts for Crohn's disease (CD) and ulcerative colitis (UC) comprising patients with ≥1 International Classification of Diseases, 9th edition, code for each disease. We used codified (i.e., International Classification of Diseases, 9th edition codes, electronic prescriptions) and narrative data from clinical notes to develop our classification model. Model development and validation was performed in a training set of 600 randomly selected patients for each disease with medical record review as the gold standard. Logistic regression with the adaptive LASSO penalty was used to select informative variables.
Results: We confirmed 399 CD cases (67%) in the CD training set and 378 UC cases (63%) in the UC training set. For both, a combined model including narrative and codified data had better accuracy (area under the curve for CD 0.95; UC 0.94) than models using only disease International Classification of Diseases, 9th edition codes (area under the curve 0.89 for CD; 0.86 for UC). Addition of natural language processing narrative terms to our final model resulted in classification of 6% to 12% more subjects with the same accuracy.
Conclusions: Inclusion of narrative concepts identified using natural language processing improves the accuracy of electronic medical records case definition for CD and UC while simultaneously identifying more subjects compared with models using codified data alone.


Animal culture should be included in conservation efforts
Animal culture should be included in conservation efforts
Southern right whale. Credit: Auckland Islands Team 2009, Oregon State University
Researchers say conservation of some of the world's most endangered species needs to take cultural knowledge of the animals into account when working out how best to protect them.
An international group of scientists, including Dr. Emma Carroll from the University of Auckland, have come up with a 'roadmap' to help conservationists make the best decisions when implementing measures to help save them.
Like humans, species such as elephants, chimpanzees and whales learn from each other. For example, meerkat pups learn how to hunt scorpions by copying adults, and whales learn migratory routes from their mothers. Over time, learned behavior can create differences between groups of animals which shape how they forage, migrate and communicate.
Beyond conserving, the authors of the paper published in Proceedings of the Royal Society B argue that understanding these socially learned behavioral differences between groups can guide decisions on how to define units (groups) to protect. It can also inform practical conservation measures, such as teaching anti-predator behaviors, or even seeding migratory routes for animals undergoing reintroduction to the wild.
"By conserving the ability of populations and groups of animals to socially learn, we help ensure they have the ability to rapidly learn how to exploit new food or habitat resources," says Dr. Carroll. "Conversely, some species are culturally 'conservative' which may mean they focus on key resources, like particular types of food that need to be conserved."
For example, socially learned migration routes by may be important to prevent entrapment in sea ice; understanding how crop-raiding behavior in elephants is spread across can assist in the management of these behaviors; and may even provide opportunities for rapid assessment, for example in New Caledonian crows, where vocal dialects may provide'markers' for rapidly mapping variation in tool-assisted foraging behavior.
"Conservation practice has long been guided by genetics and ecology that assess how unique or connected different are" says lead author Philippa Brakes of Whale and Dolphin Conservation. "We show that social learning and animal culture is another important facet of biology that can guide effective conservation strategies."
Explore further
An overview of cultural research in animals and its implications for conservation efforts
More information: Philippa Brakes et al. A deepening understanding of animal culture suggests lessons for conservation, Proceedings of the Royal Society B: Biological Sciences (2021). DOI: 10.1098/rspb.2020.2718
Citation: Animal culture should be included in conservation efforts (2021, April 21) retrieved 17 May 2021 from _URL_
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Mineral composition of high blueberry leaves and fruits depending on substrate type used for cultivation
Wydanie: 3 / 2009
Otrzymano: Brak danych
Zaakceptowano: Brak danych
Opublikowano online: 2012-08-10
Kategorie: Horticulture and forestry
In 2004-2006, an experiment was established at the Experimental Station Rajkowo belonging to the Agricultural University (West Pomeranian University of Technology) in Szczecin. High blueberry bushes were planted in an alkaline reaction (pH 7.1) heavy soil using three different substrates. The bushes were planted in trenches filled with peat, cocoa husk and sawdust. The fertilization of the plants was limited to a sole nitrogen supply (30 kg N ha-1), because chemical analyses of both the soil and the substrates showed high and/or moderate content of other nutrients. In order to decrease cocoa husk reaction and to maintain the reaction of peat and sawdust, the bushes were irrigated with H2SO4 acidified water up to pH 2.5-3.5. The bed prepared of cocoa husk was characterized by the highest N (23.8 mg 100 g-1), Zn content (51.6 mg kg-1), and pH (5.0). On the other hand, sawdust substrate had the lowest salinity (0.35 g NaCl kg-1). Sawdust substrate showed the highest level of Mn (56.5 mg kg-1) and Cu (7.4 mg kg-1) and the lowest of Ca (83 mg 100 g-1), whereas, peat substrate showed the highest salinity (0.87 g NaCl kg-1) and the lowest pH (3.8). The usage of cocoa husk substrate resulted in the highest content of N (23.6), K (6.9 g kg-1) and Mn (104.5 mg kg-1) in cv. Sierra blueberry leaves as well as N (16.0) and K (6.5 g kg-1) in berries. The plants grown in sawdust substrate showed the highest level of Ca (1.75 g kg-1), Cu (3.2) and Zn (12.4 mg kg-1), in the leaves as well as S (1.7) and Cu (3.5 mg kg-1) in berries.
Ochmian I., Grajkowski J., Mikiciuk G., Ostrowska K., Chełpiński P. 2009. Mineral composition of high blueberry leaves and fruits depending on substrate type used for cultivation. J. Elem. 14(3): 509-516.
highbush blueberry, macro-, microelements, substrates, leaves, fruit


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Machining cobalt-based dental alloys with tungsten carbide mills
Takahashi, M; Pasang, T; Conor, P; Ono, H; Tanaka, K
MetadataShow full metadata
Milling characteristics of dental alloys have been investigated and compared. The four differently configured tools used were made of cemented tungsten carbide. Most were uncoated but one was coated with a diamond-like carbon layer. The dental alloys studied were cobalt-chrome (Co-Cr) and cobalt-chrome-titanium (Co-Cr-Ti) alloys, fairly strong alloys. There is a requirement for a reliable test to evaluate the properties of dental tools by measuring the cutting forces during milling. A full characterization of dental mills is a difficult task, because the geometry of the mills is complex, with conical multi-cutting surfaces. In this study a more comprehensive understanding of the effects of cutting rate on cutting forces was achieved by varying the tool cutting speed and measuring the force on the workpiece as it was driven into the rotating tool at a fixed feed velocity. It was observed that the cutting forces were changed by varying cutting speeds. Side milling required lower forces than central slot milling. After milling the surfaces of the dental tools and dental alloy specimen were analyzed by scanning electron microscopy.


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Watch the heartwarming video where a chimpanzee babysits puppies, showcasing a gentle and nurturing bond that transcends species.
A Heartwarming Encounter in the Animal Kingdom
In a video that is as endearing as it is surprising, a chimpanzee is a babysitter for a litter of baby puppies. This unique interaction not only breaks the boundaries between species but also showcases the nurturing instincts found in the animal kingdom.
The Chimpanzee: A Gentle Caretaker
The chimpanzee, often celebrated for its intelligence and emotional capabilities, displays remarkable gentleness and care. As it meets the puppies, its actions are tentative and tender, as if understanding the fragility of these tiny creatures.
The Puppies' Response
In turn, the puppies seem equally intrigued and comfortable with their unexpected caretaker. Considering the unusual pairing, the interaction is filled with moments of curiosity, playfulness, and a surprising sense of calm.
An Unlikely Friendship
As the video progresses, viewers witness the blossoming of an unlikely friendship. The chimpanzee carefully holds, grooms, and plays with the puppies, treating them with attention and affection typically reserved for members of its species.
The Power of Nurturing Instincts
This rare moment highlights the powerful nurturing instincts that transcend species barriers. It suggests that the capacity for care and compassion might be more widespread in the animal kingdom than previously thought.
A Viral Sensation
The video quickly became a viral sensation, warming viewers' hearts worldwide. It is a beautiful reminder of the unexpected ways in which different species can interact and form bonds.
A Lesson in Compassion and Coexistence
The scene of a chimpanzee babysitting a litter of puppies is more than just a cute encounter; it's a lesson in compassion and the possibilities of peaceful coexistence among different species. It's a testament to the gentle and caring nature that many animals inherently possess.


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This paper investigates the use and extension of text retrieval and clustering techniques for event detection. The task is to automatically detect novel events from a temporally-ordered stream of news stories, either retrospectively or as the stories arrive. We applied hierarchical and non-hierarchical document clustering algorithms to a corpus of 15,836 stories, focusing on the exploitation of both content and temporal information. We found the resulting cluster hierarchies highly informative for retrospective detection of previously unidentified events, effectively supporting both query-free and query-driven retrieval. We also found that temporal distribution patterns of document clusters provide useful information for improvement in both retrospective detection and on-line detection of novel events. In an evaluation using manually labelled events to judge the system-detected events, we obtained a result of 82% in the Fl measure for retrospective detection, and a Fl value of 42% for on-line detection.
Available at: _URL_


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Asia in Iberian Converso Literature
What does Asia represent to Iberian Christian writers of Jewish descent in the sixteenth and seventeenth centuries? How do Iberian conversos represent their identities through their writings on Asia? How do the depictions of different Asian people come into play in these authors¿ notion of personal identities and nationhood? This course examines how early modern Iberian authors of Jewish heritage imagined and represented Asia in their writings, how their representation of the non-European world dialogues with contemporary events in the Iberian Peninsular, and the significance of their notions of Asians. Upon the successful completion of the course, students will full fill Gen Ed requirements (WB and LA) and gain a better understanding of Iberian converso culture in a transoceanic and multicultural frame, in addition to acquiring a good knowledge of early modern European notions of Asia.
Students may also register for this course under ASIA 71.001.


Counting Fields in a Delimited String (or Words in a String)
String Manipulation
Gavin Bollard
Version Compatibility: Visual Basic 6, Visual Basic 5
More information:
This routine was written when I was handling a series of comma delimited files (of varying sizes). I used the vb line input statement to read a line from the file into memory, and needed to be able to determine how many fields (separate data items were in it).
For example - the following string contains four fields (this routine would return a 4).
Roger Wilco, 02 9805 9809, Space Fleet Headquarters, Janitor
Since sentances are delimited by spaces, this routine could also be used to count the number of words in a string (by passing a single space as a delimiter).
This is especially useful for VB5, because in VB6 you can do a similiar thing with fewer lines of code using the Split function.
Instructions: Copy the declarations and code below and paste directly into your VB project.


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Street food in Kolkata, India
In many cities, so-called "street foods" play a large and increasing role in nutrition. Because such foods are generally low-cost, easily accessible, and cater to traditional tastes, they tend to be of particular importance in poor or informal communities and in areas experiencing high urban migration. The street food system is particularly vulnerable to deficiencies in water management. This is reflected in the fact that street vendors often have diminished infrastructural access to clean water for drinking or hygiene when compared with fixed-location providers. Moreover, street vendors often lack basic education, and rarely have formal training in food hygiene (or at times basic personal hygiene).
A 1992-3 study in Kolkata, supported by the Food and Agriculture Organization, highlighted both positive and negative aspects of street foods, and led to the "Improving Street Foods in Calcutta" program. This study led to significant changes in the management of street vending in Kolkata. For example, it identified increased provision of safe potable water and continued upgrading of waste water collection and disposal systems as critical to improving health.
Quoted from: _URL_


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Checking for Corrosion
Definition - What does Checking for Corrosion mean?
Checking, in the context of corrosion engineering, is the comprehensive monitoring of all vital elements in an industrial setting. Components that can be under checking include equipment, assets and facilities that may have signs of damage or corrosion.
For more dependable checking, it is essential to define the rate, location and the principal causes of corrosion.
Corrosion checking may also be known as corrosion inspection.
Corrosionpedia explains Checking for Corrosion
In checking for corrosion, all components that are non-conforming are detected, as these are prone to higher rates of corrosion, which may lead to failure. By monitoring, industries can have a major advantage in terms of preventive maintenance and promoting safety. Depending on the results of the checking program, sound decisions can be created.
Furthermore, checking extends the remaining life of equipment, systems or other items that are targeted by corrosion. This process also aids in choosing the right material and achieving cost effectiveness in dealing with corrosion problems.
In checking, these activities are usually involved:
- Defining critical elements
- Identification of the composition of components
- Gauging the location and degree of corrosion
- Pointing out mechanical failure
- Identifying the fitness for a reliable service situation
- Scheduling inspection
- Creation of recommendations to correct issues
- Development of strategies that mitigate corrosion


Litigation/Fraud Accounting
Litigation or Fraud accounting can also be called forensic accounting.
Forensic accounting involves the use of accounting to carry out a thorough inspection of the finances of a business or an individual. Forensic accountants are often called upon to explain financial crimes in court. The analysis carried out and the information gathered through forensic accounting are almost always useful for legal proceedings.
Forensic accountants have also been specifically trained to scrutinize the financial statements to understand the true business condition. They compile information and financial evidence, analyze and interpret them. They create computer software that helps them manage the collected information and generate reports of it.
Some of the key methods forensic accounting applies when conducting business investigations are; the use of asset identification and recovery, tracing funds and due diligence reviews.
Because of their key role in legal issues, forensic accountants may sometimes enroll for additional training in the area of alternative dispute resolution (ADR).


How to Care for Porcelain Dinnerware
Porcelain dinnerware is known for its elegance, as well as its fragility. Due to these qualities, many people choose to use their porcelain dishes only on special occasions.
Other forms of dinnerware, such as stoneware, are quite durable due to their ability to withstand the extreme hot and cold temperatures of the microwave, oven, refrigerator and freezer; many porcelain dishes cannot tolerate such conditions. In fact, most porcelain dinnerware needs to be used and cared for in a gentle and specific manner in order to preserve it.
Handwashing Tips
 2. Fill the container about halfway full of lukewarm water. Place only one or two dishes at a time in the container to avoid overloading.
 3. Use a mild liquid dish detergent and a non-abrasive cleaning tool such as a soft-bristled brush or a dish cloth to wash the porcelain dinnerware.
 4. Rinse the dishes off in a lukewarm running water, or place another container in the sink for rinsing purposes.
 5. Thoroughly dry the dishes with a soft dish towel.
Dishwashing Tips
 1. Refer to the manufacturer's care instructions when considering placing porcelain dinnerware in a dishwasher. Older porcelain or antique porcelain should be handwashed.
 2. Load the dishwasher with care by making sure that none of the porcelain dinnerware touches another piece. If dishes are allowed to rub or vibrate during the dishwasher's cycle, chipping or cracking could result.
 3. Use a gentle wash setting. Avoid using a high heat drying setting for your porcelain dinnerware. Choose a lower setting, or one with no heat.
 4. Use a mild dishwashing detergent that will not be abrasive to the porcelain.
 5. Allow the porcelain to completely cool before you attempt to remove any pieces from the dishwasher.
General Care
 1. Do not allow acidic foods to remain on your dishes. Wash them as soon as possible by using one of the methods above.
 2. Place something between the porcelain plates during storage. Napkins, paper towels or the foam pads that were part of the original packing can be used to keep the dishes from sustaining scratch or scuff marks.
 3. Never allow the porcelain to come into contact with a direct flame, as cracking can result.
 4. Warning
 Avoid using lemon or acidic detergents when cleaning porcelain dinnerware. These type of cleaners may be harmful.
 Do not leave porcelain dinnerware submerged in water for extended periods of time.


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TEXAS STATE PARKS
Natural Economic Assets
STATE PARK PROFILES
Balmorhea State Park
Balmorhea State Park is located in far West Texas in the community of Toyahvale, four miles west of Balmorhea. The 45.9-acre park's main attraction is San Solomon Springs, a spring-fed pool that covers 1.75 acres with a year-round water temperature between 72 to 76 degrees. The pool holds 3.5 million gallons, but anywhere from 22 million to 28 million gallons of fresh water flow through the pool every day. The deeper parts of the pool are in a natural state, allowing swimmers to enjoy the fish and aquatic vegetation. The park also includes the Cienega Project, a spring-fed desert wetland and canals that are home to endangered fish, a variety of aquatic life, turtles, birds and other animals.
In 2007, park attendance was about 52,000, evenly distributed between day users and overnight visitors.
The springs provided water to the American Indians and later to the Mexican farmers who used the water for their crops and dug the first irrigation canals. In the mid-1800s, the springs were called Mescalero Springs after the Apache Indians in the area, but later the Mexican farmers renamed them San Solomon Springs. Today, the clear and cool waters attract numerous swimmers and scuba divers to the area.1 In fiscal 2007, park attendance was about 52,000, evenly distributed between day users and overnight visitors.2 The park and the pool are popular with Texas and New Mexico residents. Groups enjoy coming to the park from the nearby Buffalo Trail Scout Ranch and the Historic Prude Ranch.3
In addition to the springs, the park includes a concession building, two bathhouses, the superintendent's residence and San Solomon Courts Motel, all built in Spanish Colonial style. The pool and other structures in the park were built by the Civilian Conservation Corps (CCC) in the early 1930s. By helping to preserve these CCC structures, the park is playing an important role in safeguarding the nation's heritage.
The springs are a magnet for scuba divers and dive instructors in Texas and New Mexico. At 20 feet deep, with a horizontal clarity of 80 to 100 feet and constant water temperatures, the springs provide a predictable environment for divers.4 Lead Park Ranger Tony Fleenor says, "We have divers year-round. In the off season, fall and winter, divers are our bread and butter."5
Neta Rhyne, the owner of the Toyahvale Desert Oasis dive shop, adjoining the park, says, "I like to refer to San Solomon Springs as the only dive site that provides entertainment for the whole family. One can swim, scuba dive, snorkel, sunbathe, bird watch, picnic, play in the playground, sit under a shade tree by the spring, camp and enjoy the beautiful sunrises and sunsets."6
Balmorhea State Park also plays an important role in the economic wellbeing of the surrounding communities of Toyahvale and Balmorhea, with a combined population of just over 500. "The state park has a significant positive economic impact on local businesses," says Balmorhea City Manager Terry Upshur. "The park attracts tourists to the area, increasing business for local hotel/motels, grocery stores and restaurants."7
Local area retailer Rhyne says, "My business would not exist without the park, which is the main economic catalyst for the local economy. Many other area businesses would be unable to survive without the park."8
Balmorhea State Park contributed $961,316 in sales and $522,195 in personal income to Reeves County in 2006.
In fiscal 2007, the park reported operating expenses of $443,735 for staff salaries and minor repairs, and revenues of $657,837, for a net operating gain of $214,102.9
According to a study conducted by John Crompton and Juddson Culpepper of Texas A&M University, Balmorhea State Park contributed $961,316 in sales and $522,195 in personal income to Reeves County in 2006. The park also created 19.5 jobs and generated $4,806 in sales tax revenue for the county in that year.10
Summary Economic Impacts
Balmorhea State Park, Reeves County
|2006 County Sales||2006 County
|2006 County Employment
Sales Tax Generated
Source: Texas A&M University.
Texas Parks and Wildlife Department Direct Spending (Fiscal 2007)
|Revenues||Operating Expenses*||Net Income|
* Includes salaries, operating expenses and minor (non-capital) repair.
Source: Texas Parks and Wildlife Department.
- 1 Texas Parks and Wildlife Department, "Balmorhea State Park," pp. 1-4, _URL_ (Last visited August 25, 2008.)
- 2 Data provided by Texas Parks and Wildlife Department, "State Park Sites, Acreage, and Visits," with Texas Comptroller's office calculations.
- 3 Interview with Tony Fleenor, lead park ranger at Balmorhea State Park, Toyahvale, Texas, July 24, 2008.
- 4 Yvonne Lanelli, "Balmorhea State Park, Texas," DesertUSA (September 2005), pp. 1-4, 6, _URL_ (Last visited August 25, 2008.)
- 5 Interview with Tony Fleenor, lead park ranger at Balmorhea State Park, Toyahvale, Texas, July 24, 2008.
- 6 Yvonne Lanelli, "Balmorhea State Park, Texas," DesertUSA (September 2005), p. 4.
- 7 Interview with Terry Upchurch, city manager, city of Balmorhea, Balmorhea, Texas, July 24, 2008.
- 8 Interview with Neta Rhyne, owner of the Toyahvale Desert Oasis dive shop, Toyahvale, Texas, July 24, 2008.
- 9 Data provided by Texas Parks and Wildlife Department, "Revenue Less Operating Costs, FY 2006-2007," with Texas Comptroller's office calculations. Amounts may not total due to rounding.
- 10 Texas Coalition for Conservation, The Economic Contributions of Texas State Parks in FY 2006, by John L. Crompton and Juddson Culpepper, Texas A&M University, Department of Recreation, Park and Tourism Sciences (Austin, Texas, December 2006), _URL_ (Last visited August 25, 2008.)


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Integration of entrepreneurship into educational curriculum will reduce the high rate of unemployment in Nigeria
- 1 Post
- 0 Comments
It is self evident that education is the key that unlocked the inner mind towards creativity. There are geniuses no doubt, but remember that a sage has defined genius as 99 per cent perspiration and one per cent inspiration. the developed world has long recognised the symbiotic relationship between the 'Gown' and 'Town', that's why a sizable portion of their GDP goes into research.
The bottom line is that if integration of entrepreneurship into our educational curriculum is properly planned and executed as a genuine collaboration between the Institutions and the Industries, the idea will not only help solve our unemployment problems, but equally assist in laying a solid foundation for the nation's industrial breakthrough.
Entrepreneurship study in Institution is beyond class work.if our institutions do not know how to do it,they should engage expert from outside. It's more of apprenticeship than course work.
This is a critical issue that higher institutions of learning in the developing world have to give thoughts. We will go nowhere until we learn to Do and not just to consume.
Longe Bankole-Phillips Graig-Phillips Educational Research Center 516 Ikorodu road Ketu Lagos Nigeria


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Bonaventura, Luigi and Caserta, Maurizio (2004): An adaptive evolutionary behaviour for the demand-led growth adjustment.
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Investment activity produces effects on two different economic variables. On the one hand, it adds to the existing productive capacity, on the other, it represents a component of demand. What is required for demand may not be required for accumulation, and viceversa. As a consequence different adjustment mechanisms have been put forward in the economic literature to make the two aspects of investment compatible to each other. In all cases, a distinction has been made between the fundamentally macroeconomic nature of the demand aspect, and the fundamentally microeconomic nature of the capacity-augmenting aspect. This paper tries to discuss the foundations of a non-perverse adjustment mechanism based on the internalisation of the demand aspect of investment. The adjustment mechanism discussed earlier is based on investment reacting to positive or negative excess aggregate demand. Once it is shown that a collectively efficient equilibrium can be reached even on an entirely arbitrary basis, one may set out to show that a behaviour which gets selected in a small population can be easily extended to a large one.


Korra (The Legend of Korra)
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Jump to: navigation, search
Avatar: The Last Airbender/The Legend of Korra character
Korra with her arms cross
First appearance "Welcome to Republic City"
Created by Michael Dante DiMartino
Bryan Konietzko
Voiced by
Janet Varney (Adult Korra (The Legend of Korra))
Cora Baker (Young Korra (The Legend of Korra))
Full name Avatar Korra
Aliases Raava
Species Human (waterbender)
Gender Female
Occupation Avatar (keeper of peace and order)
Title The Avatar
Family Tonraq (father)
Senna (mother)
Unalaq (Uncle)
Desna (First Cousin)
Eska (First Cousin)
Significant other(s) Naga (animal guide)
Raava (spiritual entity/deity)
Wan (distant past life)
Aang (immediate predecessor, deceased)
Children None
Relatives Unalaq (paternal uncle, deceased)
Desna (first cousin, twin)
Eska (first cousin, twin)
Religion Water Tribe
Nationality Southern Water Tribe
Age Pre-series: born in 153 ASC
The Legend of Korra: 17 in 170 ASC
Bending Element Water (native)
Hair color Brown
Eye color Baby blue
Position Protagonist
Korra is the titular character and protagonist in Nickelodeon's animated television series The Legend of Korra, a sequel to Avatar: The Last Airbender. The character was created by Michael Dante DiMartino and Bryan Konietzko and is voiced by Janet Varney.
Creation and conception[edit]
Janet Varney voices Korra
Korra's character was inspired by various female MMA fighters, as Bryan Konietzko is a fan of mixed martial arts. In addition, she was indirectly inspired by one of Bryan Konietzko's sisters. Korra was also designed to be an inversion of Aang, the title character of the preceding story Avatar: The Last Airbender. Instead of the young, spiritual Aang, Korra is a more physical character who has trouble grasping the spiritual side of being the Avatar, while Aang takes a while to master each of the elements, but connects with the spirit world instantaneously.[1]
Korra's name was settled long after her character was imagined. Konietzko and DiMartino couldn't agree to a name for her until they learned "Cora", the name of an hotel operator's dog. The name was kept, and only changed in spelling.[2]
Personality and characteristics[edit]
Unlike her predecessor Aang, Korra is described by her creators as "very tough, very headstrong, and not scared to get into a fight." [3] Although she is talented, her stubborn and hot-headed personality prevents her from easily learning Airbending or connecting with the Spirit World.[4] The Avatar traditionally has the greatest difficulty mastering the element diametrically opposed to the Avatar's personality and native bending ability. For instance, Avatar Roku -- a Firebender -- took longer to learn Waterbending and Aang -- an Airbender -- took longer to learn Earthbending. Korra's forceful, sharp-tongued personality is detested by the teachings of Airbending which encourage calm mindedness, free-spirituality, and evasiveness.
Her best friend and animal guide is a polar bear-dog named Naga, whose strength helps Korra out of many dangerous situations. Although wild polar bear dogs were originally feared and hunted by Water Tribes, Korra is the first person to ever tame one.[5] Korra is also friends with brothers Mako (love interest) and Bolin, Asami Sato, as well as the rest of Tenzin's family.
Korra's character developed and matured during episodes 11 through 12 of the first season when she was confronted with detachment from her main three bending skills, leaving her with Airbending, which she had unlocked in order to save Mako from Amon. Later, she connected to her spiritual self through Aang. Once the connection to her Avatar predecessors was established, Aang was able to bestow Energybending upon Korra (as well as her main three bending skills lost earlier). Though Korra is now able to bend all four elements while being capable of entering the Avatar State, Korra is still in the process of perfecting her Airbending skills as well as having a true connection and understanding of her spiritual self in order to complete her training as a fully realized Avatar. This will be further explored in Book 2: Spirits as Korra will learn further into the history and mythology of the distant Avatar lineage and the Spirit World.
Book One: Air[edit]
It is revealed in the plot that Korra was able to easily bend both fire and earth in addition to her native element at the age of four, thus proving her early prowess and status as the current Avatar to the Order of the White Lotus. At the age of seventeen, teenage Korra has officially mastered waterbending, earthbending, and firebending and hopes to learn airbending from the only airbending master alive, Tenzin. The elders of the Order of the White Lotus believe that Korra "lacks restraint" and should first master the spiritual side of being the Avatar, but Korra's teacher and Waterbending Master Katara reasons that, if anyone can teach the young Avatar spirituality, it is Tenzin. Tenzin and his family arrive at the White Lotus compound two weeks later, but Korra soon learns that Tenzin will not be able to stay in the Southern Water Tribe to teach her, because of the unstable conditions in Republic City.
Impatient to begin airbending training, Korra instead sneaks off to Republic City, and is eventually taken in by Tenzin after a confrontation with a bending gang and Republic City's metalbending police force. She meets the Earthbender Bolin and his Firebender brother Mako, who are a part of a pro-bending team called the Fire Ferrets, after sneaking out to see a pro-bending match. When the Fire Ferrets' waterbender doesn't show up before another match, though, Korra decides to fill in the spot. When Tenzin later sees that the spiral movements required in pro-bending helps train her in airbending, he gives permission for her to participate.
Not long into their careers, Bolin is captured by the Equalists, led by the mysterious Amon. To save Bolin, Korra and Mako sneak into an Equalist rally, and witness Amon permanently remove the bending of three members of a bending gang. After Bolin is saved, the three continue to practice and play Pro-Bending until the champion games. During the champion games, Equalists raid the bending arena, strip the opposing team of their bending, and destroy the playing field. Now no longer a member of the Fire Ferrets, as all Pro-Bending has ended, Korra focuses on the battle against Amon and the Equalists. However, she wants to avoid increasing tensions with peaceful non-benders, who are already being treated as criminals by Republic City.
Amon eventually declares full scale war against Republic City, captures the city council and easily defeats the Republic City police. Outmatched, Korra is forced to wait, along with Mako, Bolin, and Asami, until the united forces can send military aid. The aid does arrive, led by General Iroh II (Dante Basco). The five team up, and battle against Amon on different fronts. Iroh, Bolin, and Asami try to find and sabotage the Equalists' airfield and other bases of operation while Korra and Mako work together to infiltrate Republic City, which is under Amon's rule, and learn that Amon is actually an incredibly skilled waterbender and bloodbender named Noatak. Korra is, thus, unable to defeat him in a straight fight, and has her bending abilities removed by him. This loss of her three bending elements finally unlocked her dormant airbending abilities, which allows her to catch Amon off guard and defeat him by revealing his true nature as a waterbender and bloodbender to the public.
The conflict against Amon now over, Korra is terribly upset over the costs of the war and the loss of her bending. At the Southern Water Tribe, she runs away when she learns that Katara is unable to restore her bending. Her bending abilities are fully restored to her by the spirit of Aang, along with the spirits of the previous Avatars before him. She is also given the ability of Energybending. Using this newly acquired ability, she is able to undo Amon's removal of people's bending.
Book Two: Spirits[edit]
In Book Two: Spirits, taking place six months after the Anti-bending Revolution, Korra is shown racing with Tenzin's three children and wins by using the mighty, powerful Avatar State which Ikki considers to be cheating. Soon after, she, Tenzin, Mako and their respective families travel to the Southern Water Tribe for the Glacial Spirits Festival. There, she greets her uncle and chief of the Northern Water Tribe, Unalaq and her first cousins, Desna and Eska, both of whom unnerve her due to their detached nature and their general dislike of her. Later during the night, Korra is attacked by a Dark Spirit, and though she, her father, Mako and Bolin try to stop it,


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I am using a Mac mini, 2012 model, without a UPS. My assumption is that Apple has designed a special adapter to rectify high voltage and low voltage. Is that right? If I use my Mac mini without a UPS and the power surges or is lost, will the hardware be affected by the high or low voltage? Should I use a UPS?
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Why would you assume Apple designed some kind of special adapter? And what do you mean by "low voltage"? Lower than normal input voltage? – David Schwartz Oct 2 '12 at 7:39
yes.. Lower than normal input voltage and also high input – Muthu Muthu Oct 2 '12 at 7:59
1 Answer 1
up vote 2 down vote accepted
The power supply of the Mac mini supports a range of voltages (100-240V AC), but surges or brown outs may still affect it.
As with any computer, if your local electricity supply is reliable, you don't need a UPS. If your local electricity supply is unreliable, you will benefit from installing a UPS. In this respect the Mac mini is no different from any other desktop computer.
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Poteet is a city in Atascosa County, Texas, United States. The population was 3,305 at the 2000 census. It is part of the San Antonio Metropolitan Statistical Area. Poteet is known for its "Poteet Strawberry Festival" and being the birthplace of country singer George Strait. In the comic strip Steve Canyon, by Milton Caniff, Steve's daughter is named "Poteet" after the town in Texas.
Native Peoples Law Lawyers In Poteet Texas
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