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the bird is at least a year old, at which age the sexes resemble each other in all respects. Both sexes of the wild turkey are ultimately furnished with a tuft of bristles on the breast, but in two-year-old birds the tuft is about four inches long in the male |
and hardly apparent in the female; when, however, the latter has reached her fourth year, it is from four to five inches in length.*(2) * When the male courts the female, these ornaments are vibrated, and "are shewn off to great advantage," on the outstretched wings: A. Leith Adams, Field |
and Forest Rambles, 1873, p. 153. *(2) On Ardetta, Translation of Cuvier's Regne Animal, by Mr. Blyth, footnote, p. 159. On the peregrine falcon, Mr. Blyth, in Charlesworth's Mag. of Nat. Hist., vol. i., 1837, p. 304. On Dicrurus, Ibis, 1863, p. 44. On the Platalea, Ibis, vol. vi., 1864, |
p. 366. On the Bombycilla, Audubon's Ornitholog. Biography, vol. i., p. 229. On the Palaeornis, see, also, Jerdon, Birds of India, vol. i., p. 263. On the wild turkey, Audubon, ibid., vol. i., p. 15; but I hear from Judge Caton that in Illinois the female very rarely acquires a |
tuft. Analogous cases with the females of Petrcocssyphus are given by Mr. R. Sharpe, Proeedings of the Zoological Society, 1872, p. 496. These cases must not be confounded with those where diseased or old females abnormally assume masculine characters, nor with those where fertile females, whilst young, acquire the characters |
of the male, through variation or some unknown cause.* But all these cases have so much in common that they depend, according to the hypothesis of pangenesis, on gemmules derived from each part of the male being present, though latent, in the female; their development following on some slight change |
in the elective affinities of her constituent tissues. * Of these latter cases Mr. Blyth has recorded (Translation of Cuvier's Regne Animal, p. 158) various instances with Lanius, Ruticilla, Linaria, and Anas. Audubon has also recorded a similar case (Ornitholog. Biography, vol. v., p. 519) with Pyranga aestiva. A few |
words must be added on changes of plumage in relation to the season of the year. From reasons formerly assigned there can be little doubt that the elegant plumes, long pendant feathers, crests, &c., of egrets, herons, and many other birds, which are developed and retained only during the summer, |
serve for ornamental and nuptial purposes, though common to both sexes. The female is thus rendered more conspicuous during the period of incubation than during the winter; but such birds as herons and egrets would be able to defend themselves. As, however, plumes would probably be inconvenient and certainly of |
no use during the winter, it is possible that the habit of moulting twice in the year may have been gradually acquired through natural selection for the sake of casting off inconvenient ornaments during the winter. But this view cannot be extended to the many waders, whose summer and winter |
plumages differ very little in colour. With defenceless species, in which both sexes, or the males alone, become extremely conspicuous during the breeding-season,- or when the males acquire at this season such long wing or tail-feathers as to impede their flight, as with Cosmetornis and Vidua,- it certainly at first |
appears highly probable that the second moult has been gained for the special purpose of throwing off these ornaments. We must, however, remember that many birds, such as some of the birds of paradise, the Argus pheasant and peacock, do not cast their plumes during the winter; and it can |
hardly be maintained that the constitution of these birds, at least of the Gallinaceae, renders a double moult impossible, for the ptarmigan moults thrice in the year.* Hence it must be considered as doubtful whether the many species which moult their ornamental plumes or lose their bright colours during the |
winter, have acquired this habit on account of the inconvenience or danger which they would otherwise have suffered. * See Gould's Birds of Great Britain. I conclude, therefore, that the habit of moulting twice in the year was in most or all cases first acquired for some distinct purpose, perhaps |
for gaining a warmer winter covering; and that variations in the plumage occurring during the summer were accumulated through sexual selection, and transmitted to the offspring at the same season of the year; that such variations were inherited either by both sexes or by the males alone, according to the |
form of inheritance which prevailed. This appears more probable than that the species in all cases originally tended to retain their ornamental plumage during the winter, but were saved from this through natural selection, resulting from the inconvenience or danger thus caused. I have endeavoured in this chapter to shew |
that the arguments are not trustworthy in favour of the view that weapons, bright colours, and various ornaments, are now confined to the males owing to the conversion, by natural selection, of the equal transmission of characters to both sexes, into transmission to the male sex alone. It is also |
doubtful whether the colours of many female birds are due to the preservation, for the sake of protection, of variations which were from the first limited in their transmission to the female sex. But it will be convenient to defer any further discussion on this subject until I treat, in |
color="#FFFFFF" size="2">Back to Regional News Digest Saturday, September 19, 1998 Last modified at 3:24 a.m. on Saturday, September 19, 1998 State gets more rain, except in plains ALBUQUERQUE (AP) - Slightly higher averages of rain in New Mexico this summer masked big differences in precipitation levels statewide, the National Weather Service said. The state's June-through-August average was 5 percent wetter |
than normal. But while summer rains fell on the western and northern parts of the state, the eastern plains were dry, said Charlie Liles, head of the weather service's Albuquerque office. Liles said you could draw a line south from Clayton and Las Vegas, N.M., through Cloudcroft to see the demarkation: It mostly was dry to the southeast and wet |
in the northwest. Part of weather systems that steered rain away from Texas did the same to eastern New Mexico. "The dry east and southeast plains shows the westward expansion of the Texas drought that has taken place the past three to four months," Liles said.ce Clovisn got 61 percent less rain this summer, he said. Monsoons caused an unusually |
wet July across the rest of the state but then stopped in August, said Dave Gutzler, a climate researcher at the University of New Mexico. Jal, in the southeast, was the driest spot for the three-month period, with just 1.43 inches of rain, 72 percent below normal. The wettest spot was Black Lake near Angel Fire, with 14.53 inches, Liles |
said. Albuquerque was two percent below normal with 3.42 inches, while Socorro was nearly 50 percent above normal with 5.6 inches. Santa Fe had 33 percent more rain at 7.15 inches, while Las Cruces was 47 percent below normal at 2.37 inches. |
Use of Biomedical Engineering and Music for K-12 Math/Science Education The study proposes the use of Biomedical Engineering (BME) Ph.D. track graduate students to assist middle and high school teachers to teach math/science skills, by providing additional tools and training to optimize their use. The emphasis is on the use of disciplinary knowledge to enhance how people learn with the |
aid of computer technology; showing the students the importance of this knowledge to solve real world problems. Three school districts have committed to participate in a cross-disciplinary education program (Shelby County, Shades Mountain Independent, and the Alabama School of Fine Arts). Students from UAB’s Biomedical Engineering (BME) and the Alabama School of Fine Arts (ASFA) departments will develop, implement, and |
evaluate the four interventions used to enhance math/science skills. - Music education - Math/Science kits and six-week projects - Science Fair project development - A technology of Fine Arts class When the cost-effectiveness of each intervention has been determined, decisions whether to expand the intervention, within each school system will be made. Information about successful programs would be made available, |
on the internet or other media, to interested groups. Trained personnel from this project would serve as facilitators for these groups. - Investigators: A. Eberhardt, R. Thompson, M. Froning, D. Kilpadi |
The list is the origin of culture. It's part of the history of art and literature. What does culture want? To make infinity comprehensible. It also wants to create order |
— not always, but often. And how, as a human being, does one face infinity? How does one attempt to grasp the incomprehensible? Through lists, through catalogs, through collections in |
museums and through encyclopedias and dictionaries. There is an allure to enumerating how many women Don Giovanni slept with: It was 2,063, at least according to Mozart's librettist, Lorenzo da |
Ponte. We also have completely practical lists — the shopping list, the will, the menu — that are also cultural achievements in their own right. …At first, we think that |
a list is primitive and typical of very early cultures, which had no exact concept of the universe and were therefore limited to listing the characteristics they could name. But, |
in cultural history, the list has prevailed over and over again. It is by no means merely an expression of primitive cultures. A very clear image of the universe existed |
in the Middle Ages, and there were lists. A new worldview based on astronomy predominated in the Renaissance and the Baroque era. And there were lists. And the list is |
certainly prevalent in the postmodern age. It has an irresistible magic. …We like lists because we don't want to die. Here is much more. Make sure you read the quotation |
under the photo; I don't want to reproduce it on a family blog. I wonder if this interview was translated from some other language, given the difference between "lists" and |
See also the Dr. Math FAQ: order of operations Browse High School Basic Algebra Stars indicate particularly interesting answers or good places to begin browsing. Selected answers to common questions: |
a rational - Number of Equations Needed in a Simultaneous Linear System [10/29/2003] Could you tell me why we need the same number of equations as variables in order to |
get a unique solution to a system of simultaneous linear equations? - Number * Sum of Remaining Four Numbers [04/03/2003] Find 5 numbers such that when each number is multiplied |
by the sum of the remaining 4 numbers, the following values will result: 152, 245, 297, 320, 360. - Objects in a Pyramid [7/8/1996] Objects are stacked in a triangular |
pyramid... how many objects are in the nth layer from the top? - Old Test Questions Answered [1/23/1995] I am studying for my midterm, and I've come across two questions |
variables have the same exponent? What about negative exponents and descending - Ordering Products, Powers, and Parameters of Trigonometric Functions [10/31/2010] A student wants to know how to unambiguously interpret |
strings of trigonometric functions, multiplication, and exponentiation. Doctor Peterson digs into a history book -- as well as another math doctor's conversation -- to illuminate the vagaries of the - |
Order in Linear Expressions [11/20/2001] Can you give me a convincing argument as to why, in an equation such as y=13-7x, where y is a function of x, it should |
questions to answer and I could do all except two: 1) A framed rectangular picture is 35cm long and 25cm wide... 2) The base of a triangle is 9cm more |
formula to find if a point exists on a line? Both are in x,y form. - Polynomial Brain-Twisters [12/4/1995] I'm stumped on some similar polynomial problems... - Polynomial Degrees and |
of women in two different years. - Positive Unit Fractions [10/02/2002] Find five different positive unit fractions whose sum is 1. (A unit fraction is a fraction whose numerator is |
1. All denominators must also be natural numbers.) - Precedence of Unary Operators [09/01/99] The PEMDAS rule for order of operations ignores unary operators. Can you explain the proper precedence |
for them, and give an example showing how not knowing the rule can cause an incorrect result? - Preparing for an Algebra Test [11/1/1995] A 9th grade math student asks |
for help preparing for final exams. What is the difference between the terms: solve and simplify? How do you find the gradient in a graph? - Prize Money [09/04/1997] If |
first prize wins $1,000 out of $6,000 and twentieth prize wins $100, how much money do second through nineteenth place win? Is this a - Probability of a Function Having |
Hydrocele Operation: aka Hydroceles, Hydrocele Sac, Swollen Testicle, Hydrocelectomy What is it? Hydrocele operations or hydrocele surgery is to release fluid that forms in a sac within the scrotum. Typically hydroceles develop when the testicle passes into the scrotum but the passage through which this occur fails to close properly. Fluid can accumulate in this passage from the abdomen, and then enters the scrotum |
causing it to swell. This can cause one or both sides of the scrotum to swell and the testicle itself to swell or become damage and inflamed. Fluid can also block the tube where sperm typically flow from. Hydroceles are more common in newborn boys but are not exclusive to newborn boys. To diagnose a hydrocele typically a doctor will look for swelling in |
the scrotum caused primarily by fluid build up or will look for something solid like a fluid-filled sac in the scrotum. Typically fluid is removed from the hydrocele sac during a procedure called a hydrocelectomy. For the most part this is a straightforward and uncomplicated procedure that may produce a moderate amount of soreness for a few days following the procedure. The long-term benefits |
far outweigh any short-term soreness. Many times the patient is a young patient under the age of 10 or in many cases a newborn baby that is born with a hydrocele defect. Usually a surgery takes placed under general anesthesia. A surgeon will make a small incision in the scrotum that will allow fluid to be drained from the scrotum and then seal the |
passage from the scrotum to the abdomen. Usually the incision is then closed with stitches that will dissolve on their own so they do not have to be removed later. Alternatives to Surgery There are no known alternatives to this surgery currently. Before the Operation Prior to the operation the doctor will confirm a fluid filled sac exists by placing a light to the |
scrotum which will light up the testicles, veins in the scrotum and the fluid filled sac which will appear clear to the light. A doctor will also perform a comprehensive medical history and check any medications the patient is currently taking. Patients are advised not to eat or drink anything up to 12 hours before the procedure because it is performed under general anesthesia. |
After the Operation- At Home Once the operation is complete the patient will recover usually for a few hours in a day bed. The procedure is usually performed on an outpatient basis meaning the patient can usually go home on the same day. Most of the time it is best to wear looser fitting close that will prevent irritation and discomfort on leaving. There |
are some risks associated with this procedure as there are with any procedure including a small risk of infection. Other risks including the risk of bleeding during or after the procedure, and a risk of a blood clot forming in the area of the procedure. The doctor may accidentally damage the scrotum or the tissues surrounding this area too. Anytime a patient undergoes general |
anesthesia there are risks associated with this too including a risk of pneumonia following surgery. The nurse or doctor will encourage the patient to take deep breaths to clear the lungs following surgery. Many people especially younger children undergoing this operation may report feeling nauseous or dizzy following the procedure, a side effect largely associated with the general anesthesia. These complications are usually temporary |
however and resolve within a couple of days of treatment. A hydrocele procedure is generally performed to relieve fluid build up around the testicle or within the scrotum. This procedure is relatively simple with few complications. The primary risks include a risk of infection and risk of rupture or nicks to nearby tissues or structures. If you work with a competent health professional you |
reduce your odds of complications. Because these surgeries are often performed on younger individuals it pays to ask someone if they have experience working on youths or pediatric patients. You may need to pay a small amount extra to work with someone that specializes in pediatrics or even geriatrics if you are over 50 or 60 and have a fluid-filled sac in the scrotum |
that you require surgery for. Regardless of where you go or who you see make sure they practice safe hygiene practices to ensure your safety and wellness. Estimated Costs for Hydrocele Operation The cost of surgery varies widely and may depend partly on the patient’s age and overall health and wellness. Patients that do not require extensive health accommodations or hospital stays are likely |
to have to pay the least in adjunctive healthcare therapy. That said you should always be prepared to foot the bill for extra expenses including any complications that may rise from treatment. Health insurance may offset some of these costs. Keep in mind there may be separate fees associated with anesthesia. The hospital and anesthesia fees are usually separate from the fees charged for |
the procedure itself, although some medical tourism companies tend to provide all-inclusive packages for their patients. This may be the best option for individuals that plan to travel abroad already and want to fit in a little health care while traveling for pleasure. |Country||Costs Hydrocele Operation| |
The Centre is associated with several major research projects (especially the Dictionary of Old English), six publication series (Toronto Medieval Latin Texts, Toronto Medieval Bibliographies, Toronto Texts and Translations, Toronto Old English Series, Publications of the Dictionary of Old English—in addition to seven publication series and a prestigious journal published by the Pontifical Institute of Mediaeval Studies (PIMS), a medieval |
drama group, and a medieval music group. The result is a large interactive community of professionals working in many areas of medieval studies. Individual research projects have all thrived in this environment. Dictionary of Old English The Dictionary of Old English (DOE) defines the vocabulary of the first centuries (AD 600–1150) of the English language, using today’s most advanced technology. |
The DOE is based on a computerized Corpus comprising at least one copy of each text surviving in Old English. The total size is about six times the collected works of Shakespeare. The body of surviving Old English texts encompasses a rich diversity of records written on parchment, carved in stone and inscribed in jewellery. |
Welcome to MedLibrary.org. For best results, we recommend beginning with the navigation links at the top of the page, which can guide you through our collection of over 14,000 medication labels and package inserts. For additional information on other topics |
which are not covered by our database of medications, just enter your topic in the search box below: Chromatography [|krəʊmə|tɒgrəfi] (from Greek χρῶμα chroma "color" and γράφειν graphein "to write") is the collective term for a set of laboratory techniques |
for the separation of mixtures. The mixture is dissolved in a fluid called the mobile phase, which carries it through a structure holding another material called the stationary phase. The various constituents of the mixture travel at different speeds, causing |
them to separate. The separation is based on differential partitioning between the mobile and stationary phases. Subtle differences in a compound's partition coefficient result in differential retention on the stationary phase and thus changing the separation. Chromatography may be preparative |
or analytical. The purpose of preparative chromatography is to separate the components of a mixture for more advanced use (and is thus a form of purification). Analytical chromatography is done normally with smaller amounts of material and is for measuring |
the relative proportions of analytes in a mixture. The two are not mutually exclusive. Chromatography, literally "color writing", was first employed by Russian-Italian scientist Mikhail Tsvet in 1900. He continued to work with chromatography in the first decade of the |
20th century, primarily for the separation of plant pigments such as chlorophyll, carotenes, and xanthophylls. Since these components have different colors (green, orange, and yellow, respectively) they gave the technique its name. New types of chromatography developed during the 1930s |
and 1940s made the technique useful for many separation processes. Chromatography technique developed substantially as a result of the work of Archer John Porter Martin and Richard Laurence Millington Synge during the 1940s and 1950s. They established the principles and |
basic techniques of partition chromatography, and their work encouraged the rapid development of several chromatographic methods: paper chromatography, gas chromatography, and what would become known as high performance liquid chromatography. Since then, the technology has advanced rapidly. Researchers found that |
the main principles of Tsvet's chromatography could be applied in many different ways, resulting in the different varieties of chromatography described below. Advances are continually improving the technical performance of chromatography, allowing the separation of increasingly similar molecules. Chromatography terms |
- The analyte is the substance to be separated during chromatography. - Analytical chromatography is used to determine the existence and possibly also the concentration of analyte(s) in a sample. - A bonded phase is a stationary phase that is |
covalently bonded to the support particles or to the inside wall of the column tubing. - A chromatogram is the visual output of the chromatograph. In the case of an optimal separation, different peaks or patterns on the chromatogram correspond |
to different components of the separated mixture. - Plotted on the x-axis is the retention time and plotted on the y-axis a signal (for example obtained by a spectrophotometer, mass spectrometer or a variety of other detectors) corresponding to the |
response created by the analytes exiting the system. In the case of an optimal system the signal is proportional to the concentration of the specific analyte separated. - A chromatograph is equipment that enables a sophisticated separation e.g. gas chromatographic |
or liquid chromatographic separation. - Chromatography is a physical method of separation that distributes components to separate between two phases, one stationary (stationary phase), while the other (the mobile phase) moves in a definite direction. - The eluate is the |
mobile phase leaving the column. - The eluent is the solvent that carries the analyte. - An eluotropic series is a list of solvents ranked according to their eluting power. - An immobilized phase is a stationary phase that is |
immobilized on the support particles, or on the inner wall of the column tubing. - The mobile phase is the phase that moves in a definite direction. It may be a liquid (LC and Capillary Electrochromatography (CEC)), a gas (GC), |
or a supercritical fluid (supercritical-fluid chromatography, SFC). The mobile phase consists of the sample being separated/analyzed and the solvent that moves the sample through the column. In the case of HPLC the mobile phase consists of a non-polar solvent(s) such |
as hexane in normal phase or polar solvents in reverse phase chromotagraphy and the sample being separated. The mobile phase moves through the chromatography column (the stationary phase) where the sample interacts with the stationary phase and is separated. - |
Preparative chromatography is used to purify sufficient quantities of a substance for further use, rather than analysis. - The retention time is the characteristic time it takes for a particular analyte to pass through the system (from the column inlet |
to the detector) under set conditions. See also: Kovats' retention index - The sample is the matter analyzed in chromatography. It may consist of a single component or it may be a mixture of components. When the sample is treated |
in the course of an analysis, the phase or the phases containing the analytes of interest is/are referred to as the sample whereas everything out of interest separated from the sample before or in the course of the analysis is |
referred to as waste. - The solute refers to the sample components in partition chromatography. - The solvent refers to any substance capable of solubilizing another substance, and especially the liquid mobile phase in liquid chromatography. - The stationary phase |
is the substance fixed in place for the chromatography procedure. Examples include the silica layer in thin layer chromatography Chromatography is based on the concept of partition coefficient. Any solute partitions between two immiscible solvents. When we make one solvent |
immobile (by adsorption on a solid support matrix) and another mobile it results in most common applications of chromatography. If matrix support is polar (e.g. paper, silica etc.) it is forward phase chromatography, and if it is non polar (C-18) |
it is reverse phase. Techniques by chromatographic bed shape Column chromatography Column chromatography is a separation technique in which the stationary bed is within a tube. The particles of the solid stationary phase or the support coated with a liquid |
stationary phase may fill the whole inside volume of the tube (packed column) or be concentrated on or along the inside tube wall leaving an open, unrestricted path for the mobile phase in the middle part of the tube (open |
tubular column). Differences in rates of movement through the medium are calculated to different retention times of the sample. In 1978, W. C. Still introduced a modified version of column chromatography called flash column chromatography (flash). The technique is very |
similar to the traditional column chromatography, except for that the solvent is driven through the column by applying positive pressure. This allowed most separations to be performed in less than 20 minutes, with improved separations compared to the old method. |
Modern flash chromatography systems are sold as pre-packed plastic cartridges, and the solvent is pumped through the cartridge. Systems may also be linked with detectors and fraction collectors providing automation. The introduction of gradient pumps resulted in quicker separations and |
less solvent usage. In expanded bed adsorption, a fluidized bed is used, rather than a solid phase made by a packed bed. This allows omission of initial clearing steps such as centrifugation and filtration, for culture broths or slurries of |
broken cells. Phosphocellulose chromatography utilizes the binding affinity of many DNA-binding proteins for phosphocellulose. The stronger a protein's interaction with DNA, the higher the salt concentration needed to elute that protein. Planar chromatography Planar chromatography is a separation technique in |
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