thought was : ‘ is this a jew? they certainly did not have this appearance in linz. ’ but the longer i gazed at the strange countenance and examined it feature by feature, the more the question shaped itself in my mind : ‘ is this a german? ’ ” view entire story here. it was at this juncture that hitler began to consider the role of the jew in germany ’ s cultural life : “ as soon as i began to investigate the matter and observe the jews, then vienna appeared to me in a different light. what soon gave me cause for very serious consideration were the activities of the jews in certain branches of life. was there any undertaking, any form of foulness, especially in cultural life, in which at least one jew did not participate? i discovered the jewish activities in the press, in art, in literature and the theatre. one needed only to look at the posters announcing the hideous productions of the cinema and study the names of the authors in order to become permanently adamant on jewish questions. here was a pestilence with which the public was being infected. i began to carefully investigate the names of all the fabricators of these unclean products. the result of that inquiry was still more disfavourable to the attitude to which i had hitherto held in regard to the jews. the fact that nine - tenths of all the smutty literature, artistic tripe and theatrical banalities, had to be charged to the account of people who formed scarcely one per cent of the nation - that fact could not be gainsaid. ” view entire story here & here. no hint of racial profiling here, dear readers. and as the saying goes, “ plus ca change, plus c ’ est la meme chose. ” for although hitler did try to change the cultural degradation perpetrated by german jewry - the moral depravity remains the same throughout the western world. the brother nathanael foundation, po box 1242, frisco co 80443


tiny wiki : fast loading, text only version of wikipedia. redirect6 | pianoforte | earlier versions of the instrument | fortepiano | other uses of " piano " | piano ( disambiguation ) the piano is a musical instrument which is played by means of a keyboard. widely used in western music for solo performances, ensemble use, chamber music, and accompaniment, the piano is also very popular as an aid to composing and rehearsal. although not portable and often expensive, the piano ' s versatility and ubiquity have made it one of the world ' s most familiar musical instruments. pressing a key on the piano ' s keyboard causes a felt covered hammer to strike steel strings. the hammers rebound, allowing the strings to continue vibrating at their resonant frequency. these vibrations are transmitted through a bridge to a sounding board that couples the acoustic energy to the air so that it can be heard as sound. when the key is released, a damper stops the string ' s vibration. pianos are sometimes classified as both percussion and stringed instruments. according to the hornbostel - sachs method of music classification, they are grouped with chordophones. the word ' ' piano ' ' is a shortened form of the word ' ' pianoforte ' ', which is seldom used except in formal language and derived from the original italian name for the instrument, ' ' clavicembalo ' ' [ or ' ' gravicembalo ' ' ] ' ' col piano e forte ' ' ( literally ' ' harpsichord with soft and loud ' ' ). this refers to the instrument ' s responsiveness to keyboard touch, which allows the pianist to produce notes at different dynamic levels by controlling the speed with which the hammers hit the strings. the piano is founded on earlier technological innovations. the first string instruments with struck strings were the hammered dulcimers originating from the persian traditional musical instrument santur. during the middle ages, there were several attempts at creating stringed keyboard instruments with struck strings, the earliest being the hurdy gurdy which has uncertain origins. by the 17th century, the mechanisms of keyboard instruments such as the clavichord and the harpsichord were well known. in a clavichord the strings are struck by tangents, while in a harpsichord they are plucked by quills. centuries of work on the mechanism of the harpsichord in particular had shown the most effective ways to construct the case, soundboard, bridge, and keyboard. the invention of the modern piano is credited


, while in a harpsichord they are plucked by quills. centuries of work on the mechanism of the harpsichord in particular had shown the most effective ways to construct the case, soundboard, bridge, and keyboard. the invention of the modern piano is credited to bartolomeo cristofori ( 1655 - 1731 ) of padua, italy, who was employed by prince ferdinand de medici as the keeper of the instruments. he was an expert harpsichord maker and was well acquainted with the previous body of knowledge on stringed keyboard instruments. it is not known exactly when cristofori first built a piano. an inventory made by his employers, the medici family, indicates the existence of a piano by the year 1700 ; another document of doubtful authenticity indicates a date of 1698. the three cristofori pianos that survive today date from the 1720s. cristofori ' s great success was in solving, without any prior example, the fundamental mechanical problem of piano design : the hammer must strike the string, but not remain in contact with it ( as a tangent remains in contact with a clavichord string ) because this would damp the sound. moreover, the hammer must return to its rest position without bouncing violently, and it must be possible to repeat a note rapidly. cristofori ' s piano action served as a model for the many different approaches to piano actions that followed. while cristofori ' s early instruments were made with thin strings and were much quieter than the modern piano, compared to the clavichord ( the only previous keyboard instrument capable of minutely controlled dynamic nuance through the keyboard ) they were considerably louder and had more sustaining power. cristofori ' s new instrument remained relatively unknown until an italian writer, scipione maffei, wrote an enthusiastic article about it ( 1711 ), including a diagram of the mechanism. this article was widely distributed, and most of the next generation of piano builders started their work because of reading it. one of these builders was gottfried silbermann, better known as an organ builder. silbermann ' s pianos were virtually direct copies of cristofori ' s, with one important addition : silbermann invented the forerunner of the modern damper pedal, which lifts all the dampers from the strings at once. silbermann showed johann sebastian bach one of his early instruments in the 1730s, but bach did not like it at that time, claiming that the higher notes were too soft to allow a full dynamic range. although


from the strings at once. silbermann showed johann sebastian bach one of his early instruments in the 1730s, but bach did not like it at that time, claiming that the higher notes were too soft to allow a full dynamic range. although this earned him some animosity from silbermann, the criticism was apparently heeded. bach did approve of a later instrument he saw in 1747, and even served as an agent in selling silbermann ' s pianos. piano making flourished during the late 18th century in the viennese school, which included johann andreas stein ( who worked in augsburg, germany ) and the viennese makers nannette streicher ( daughter of stein ) and anton walter. viennese - style pianos were built with wood frames, two strings per note, and had leather - covered hammers. some of these viennese pianos had the opposite coloring of modern - day pianos ; the natural keys were black and the accidental keys white. [ ] it was for such instruments that wolfgang amadeus mozart composed his concertos and sonatas, and replicas of them are built today for use in authentic - instrument performance of his music. the pianos of mozart ' s day had a softer, clearer tone than today ' s pianos or english pianos, with less sustaining power. the term ' ' fortepiano ' ' is nowadays often used to distinguish the 18th - century instrument from later pianos. the modern piano ( the pianoforte ) was developed from the harpsichord around 1720, by bartolomeo cristofori of padua, italy. his new instrument had a delicate pianissimo ( very soft sound ), a strong fortissimo ( a very loud, forceful sound ), and every level in between. the first upright piano was made around 1780 by johann schmidt of salzburg, austria. thomas loud of london developed an upright piano whose strings ran diagonally ( in 1802 ), saving even more space. development of the modern piano in the period lasting from about 1790 to 1860, the mozart - era piano underwent tremendous changes that led to the modern form of the instrument. this revolution was in response to a consistent preference by composers and pianists for a more powerful, sustained piano sound, and made possible by the ongoing industrial revolution with technological resources such as high - quality steel, called piano wire, for strings, and precision casting for the production of iron frames. over time, the tonal range of the piano was also increased from the five octaves of mozart ' s day to the 7


such as high - quality steel, called piano wire, for strings, and precision casting for the production of iron frames. over time, the tonal range of the piano was also increased from the five octaves of mozart ' s day to the 7al or more octaves found on modern pianos. early technological progress owed much to the firm of broadwood. john broadwood joined with another scot, robert stodart, and a dutchman, americus backers, to design a piano in the harpsichord case a€ “ the origin of the " grand ". they achieved this in about 1777. they quickly gained a reputation for the splendour and powerful tone of their instruments, with broadwood constructing ones that were progressively larger, louder, and more robustly constructed. they sent pianos to both joseph haydn and ludwig van beethoven, and were the first firm to build pianos with a range of more than five octaves : five octaves and a fifth during the 1790s, six octaves by 1810 ( beethoven used the extra notes in his later works ), and seven octaves by 1820. the viennese makers similarly followed these trends, however the two schools used different piano actions : broadwoods were more robust, viennese instruments were more sensitive. by the 1820s, the center of innovation had shifted to paris, where the pleyel firm manufactured pianos used by fra©da©ric chopin and the a ‰ rard firm manufactured those used by franz liszt. in 1821, sa©bastien a ‰ rard invented the double escapement action, which permitted a note to be repeated even if the key had not yet risen to its maximum vertical position. this facilitated rapid playing of repeated notes, and this musical device was pioneered by liszt. when the invention became public, as revised by henri herz, the double escapement action gradually became standard in grand pianos, and is still incorporated into all grand pianos currently produced. one of the major technical innovations that helped to create the sound of the modern piano was the use of a strong iron frame. also called the " plate ", the iron frame sits atop the soundboard, and serves as the primary bulwark against the force of string tension. the increased structural integrity of the iron frame allowed the use of thicker, tenser, and more numerous strings. in a modern grand the total string tension can exceed 20 tons. the single piece cast iron frame was patented in 1825 in boston by alpheus babcock, combining the metal hitch pin plate ( 1821,


, tenser, and more numerous strings. in a modern grand the total string tension can exceed 20 tons. the single piece cast iron frame was patented in 1825 in boston by alpheus babcock, combining the metal hitch pin plate ( 1821, claimed by broadwood on behalf of samuel herva© ) and resisting bars ( thom and allen, 1820, but also claimed by broadwood and a ‰ rard ). babcock later worked for the chickering & mackays firm who patented the first full iron frame for grand pianos in 1843. composite forged metal frames were preferred by many european makers until the american system was fully adopted by the early 20th century. other innovations for the mechanism included the use of felt hammer coverings instead of layered leather hammers. felt hammers, which were first introduced by henri pape in 1826, were a more consistent material, permitting wider dynamic ranges as hammer weights and string tension increased. the sostenuto pedal ( see below ), invented in 1844 by jean louis boisselot and improved by the steinway firm in 1874, allowed a wider range of effects. other important technical innovations of this era included changes to the way the piano was strung, such as the use of a " choir " of three strings rather than two for all but the lower notes, and the use of different stringing methods. with the over strung scale, also called " cross - stringing ", the strings are placed in a vertically overlapping slanted arrangement, with two heights of bridges on the soundboard instead of just one. this permits larger, but not necessarily longer, strings to fit within the case of the piano. over stringing was invented by jean - henri pape during the 1820s, and first patented for use in grand pianos in the united states by henry steinway jr. in 1859. with duplexes or aliquot scales, which was patented in 1872 by theodore steinway, the different components of string vibrations are controlled by tuning their secondary parts in octave relationships with the sounding lengths. similar systems developed by blalthner ( 1872 ), as well as [ http : / / mediatheque. cite - musique. fr / clientbooklinecimu / recherche / noticedetaillebyid. asp? id = 0162147 taskin ] ( 1788 ), and collard ( 1821 ) used more distinctly ringing undamped vibrations to modify tone. some early pianos had shapes and designs that are no longer in use. the square piano had horizontal strings arranged diagonally across


by the end of the 19th century. improvements have been made in manufacturing processes, and many individual details of the instrument continue to receive attention. history and musical performance much of the most widely admired piano repertoire, for example, that of haydn, mozart, and beethoven, was composed for a type of instrument that is rather different from the modern instruments on which this music is normally performed today. even the music of the romantics, including liszt, chopin, robert schumann, felix mendelssohn and johannes brahms, was written for pianos substantially different from ours. modern pianos come in two basic configurations ( with subcategories ) : the grand piano and the upright piano. in grand pianos, the frame and strings are horizontal, with the strings extending away from the keyboard. there are several sizes of grand piano. a rough generalization distinguishes the " concert grand " ( between about and long ) from the " parlor grand " or " boudoir grand " ( about to ) and the smaller " baby grand ". all else being equal, longer pianos with longer strings have larger, richer sound and lower inharmonicity of the strings. inharmonicity is the degree to which the frequencies of overtones ( known as partials, partial tones, or harmonics ) depart from whole multiples of the fundamental frequency. pianos with shorter, thicker, and stiffer strings ( e. g., baby grands ) have more inharmonicity. the longer strings on a concert grand can vibrate more freely than the shorter, thicker strings on a baby grand, which means that a concert grand ' s strings will have truer overtones. this allows the strings to be tuned closer to equal temperament in relation to the standard pitch with less " stretching " in the piano tuning. full - size grands are usually used for public concerts, whereas smaller grands, introduced by sohmer & co. in 1884, are often chosen for domestic use where space and cost are considerations. a grand piano action has a repetition lever for each key. if the key is pressed repeatedly and fairly quickly this repetition lever catches the hammer close to the strings, which assists the speed and control of repeated notes and trills. upright pianos, also called vertical pianos, are more compact because the frame and strings are vertical. the hammers move horizontally, and are returned to their resting position by springs which are prone to wear and tear. upright pianos with unusually tall frames and long strings are sometimes called " upright grand " pianos. some authors classify modern pianos


strings are vertical. the hammers move horizontally, and are returned to their resting position by springs which are prone to wear and tear. upright pianos with unusually tall frames and long strings are sometimes called " upright grand " pianos. some authors classify modern pianos according to their height and, to modifications of the action that are necessary to accommodate the height. * studio pianos are around 42 to 45 inches tall. this is the shortest cabinet that can accommodate a ' full - sized ' action located above the keyboard. * console pianos have a compact action ( shorter hammers ), and are a few inches shorter than studio models. * the top of a spinet model barely rises above the keyboard. the action is located below, operated by vertical wires that are attached to the backs of the keys. * anything taller than a studio piano is called an upright. toy pianos began to be manufactured in the 19th century. in 1863, henri fourneaux invented the player piano, which " plays itself " from a piano roll without the need for a pianist. a performance is " recorded " onto rolls of paper with perforations, and the player piano replays the performance using pneumatic devices. modern equivalents of the player piano include the ba ¶ sendorfer ceus and the yamaha disklavier, using solenoids and midi rather than pneumatics and rolls. a silent piano is an acoustic piano having an option to silence the strings by means of an interposing hammer bar. they are designed for private silent practice. the transposing piano was invented in 1801 by edward ryley. it has a lever under the keyboard used to move the keyboard relative to the strings so that a pianist can play in a familiar key while the music sounds in a different key. the prepared piano, encountered in some contemporary art music, is a grand piano which has objects placed inside it to alter its sound, or which has had its mechanism changed in some other way. the scores for music for prepared piano specify the modifications, for example instructing the pianist to insert pieces of rubber, or paper, or metal screws or washers, in between the strings. these either mute the strings or alter their timbre. available since the 1980s, digital pianos use digital sampling technology to reproduce the sound of each piano note. digital pianos can be sophisticated, with features including working pedals, weighted keys, multiple voices, and midi interfaces. however, when the damper pedal ( see below ) is depressed on such an instrument, there are no strings to vibrate


note. digital pianos can be sophisticated, with features including working pedals, weighted keys, multiple voices, and midi interfaces. however, when the damper pedal ( see below ) is depressed on such an instrument, there are no strings to vibrate sympathetically. physical models of sympathetic vibration are incorporated into the synthesis software of some higher end digital pianos, such as the yamaha clavinova series, or the kawai mp8 series. with the advent of powerful desktop computers, highly realistic pianos have become available as affordable software modules. some of these modules, such as synthogy ' s ivory released in 2004, use multi - gigabyte piano sample sets with as many as 90 recordings, each lasting many seconds, for each of the 88 ( some have 81 ) keys under different conditions, augmented by additional samples to emulate sympathetic resonance, key release, the drop of the dampers, and simulations of piano techniques like re - pedaling. some other software modules, such as modartt ' s pianoteq released in 2006, use no samples whatsoever and are a pure synthesis of all aspects of the physicalities which go into the creation of a real piano ' s sound. in recent times, piano manufactures have superseded the old fashioned pianola or player piano with new innovative pianos which play themselves via a cd or mp3 player. similar in concept to a player piano, the pianodisc or iq systems installed in select pianos will ' play themselves ' when prompted by a certain file format designed to be interpreted by software installed and connected to the piano. such additions are quite expensive, often doubling the cost of a piano and are available in both upright and grand pianos. almost every modern piano has 36 black keys and 52 white keys for a total of 88 keys ( seven octaves plus a minor third, from a0 to c8 ). many older pianos only have 85 keys ( seven octaves from a0 to a7 ), while some manufacturers extend the range further in one or both directions. some ba ¶ sendorfer pianos extend the normal range downwards to f0, with one other model going as far as a bottom c0, making a full eight octave range. these extra keys are sometimes hidden under a small hinged lid that can be flipped down to cover the keys in order to avoid visual disorientation in a pianist unfamiliar with the extended keyboard. on others, the colors of the extra white keys are reversed ( black instead of white ). the extra keys are added primarily for increased resonance from the associated strings ; that is


avoid visual disorientation in a pianist unfamiliar with the extended keyboard. on others, the colors of the extra white keys are reversed ( black instead of white ). the extra keys are added primarily for increased resonance from the associated strings ; that is, they vibrate sympathetically with other strings whenever the damper pedal is depressed and thus give a fuller tone. only a very small number of works composed for piano actually use these notes. more recently, the stuart and sons company has also manufactured extended - range pianos, with the first 102 key piano. on their instruments, the frequency range extends from c0 to f8 which is the widest practical range for the acoustic piano. the extra keys are the same as the other keys in appearance. small studio upright acoustical pianos with only 65 keys have been manufactured for use by roving pianists. known as " gig " pianos and still containing a cast iron harp, these are comparatively lightweight and can be easily transported to and from engagements by only two people. as their harp is longer than that of a spinet or console piano, they have a stronger bass sound that to some pianists is well worth the trade - off in range that a reduced key - set offers. the toy piano manufacturer schoenhut started manufacturing both grands and uprights with only 44 or 49 keys, and shorter distance between the keyboard and the pedals. these pianos are true pianos with action and strings. the pianos were introduced to their product line in response to numerous requests in favor of it. pianos have had pedals, or some close equivalent, since the earliest days. ( in the 18th century, some pianos used levers pressed upward by the player ' s knee instead of pedals. ) most grand pianos have three pedals : the soft pedal ( una corda ), sostenuto, and sustain pedal ( from left to right, respectively ). most modern upright pianos also have three pedals : soft pedal, practice pedal and sustain pedal, though older or cheaper models may lack the practice pedal. the sustain pedal ( or, damper pedal ) is often simply called " the pedal ", since it is the most frequently used. it is placed as the rightmost pedal in the group. it lifts the dampers from all keys, sustaining all played notes. in addition, it alters the overall tone by allowing all strings, even the ones not directly played, to reverberate. the soft pedal or ' ' una corda ' ' pedal is placed leftmost in the row of


played notes. in addition, it alters the overall tone by allowing all strings, even the ones not directly played, to reverberate. the soft pedal or ' ' una corda ' ' pedal is placed leftmost in the row of pedals. in grand pianos, it shifts the entire action, including the keyboard, to the right, so that the hammers hit only one of the three strings for each note ( hence the name ' ' una corda ' ', or ' one string ' ). the effect is to soften the note as well as to change the tone. in uprights, this action is not possible, and so the pedal moves the hammers closer to the strings, allowing the hammers to hit the strings with less kinetic energy to produce a softer sound, but with no change in timbre. on grand pianos, the middle pedal is a sostenuto pedal. this pedal keeps raised any damper that was already raised at the moment the pedal is depressed. this makes it possible to sustain some notes ( by depressing the sostenuto pedal before notes to be sustained are released ) while the player ' s hands are free to play other notes. this can be useful for musical passages with pedal points and other otherwise tricky or impossible situations. on many upright pianos, there is a middle pedal called the ' practice ' or ' ' celeste ' ' pedal. this drops a piece of felt between the hammers and strings, greatly muting the sounds. there are also non - standard variants. on some pianos ( grands and verticals ), the middle pedal can be a bass sustain pedal : that is, when it is depressed, the dampers lift off the strings only in the bass section. this pedal would be used only when a pianist needs to sustain a single bass note or chord over many measures, while playing the melody in the treble section. on the stuart and sons piano as well as the largest fazioli piano, there is a fourth pedal to the left of the principal three. this fourth pedal works in the same way as the soft pedal of an upright piano, moving the hammers closer to the strings. the rare transposing piano, of which irving berlin possessed an example, had a middle pedal that functioned as a clutch which disengages the keyboard from the mechanism, enabling the keyboard to be moved to the left or right with a lever. the entire action of the piano is thus shifted to allow the pianist to play music written in one key so that it sounds


which disengages the keyboard from the mechanism, enabling the keyboard to be moved to the left or right with a lever. the entire action of the piano is thus shifted to allow the pianist to play music written in one key so that it sounds in a different key. the ' ' pedalier ' ' piano, or pedal piano, is a rare type of piano that includes a pedalboard, enabling bass register notes to be played with the feet, as is standard on the organ. there are two types of pedal piano : the pedal board may be an integral part of the instrument, using the same strings and mechanism as the manual keyboard, or, less frequently, it may consist of two independent pianos ( each with its separate mechanics and strings ) which are placed one above the other, a regular piano played by the hands and a bass - register piano played by the feet. many parts of a piano are made of materials selected for sturdiness. in quality pianos, the outer rim of the piano is made of a hardwood, normally maple or beech. according to [ http : / / www. speech. kth. se / music / 5 _ lectures / conklin / thepianocase. html harold a. conklin ], the purpose of a sturdy rim is so that " the vibrational energy will stay as much as possible in the soundboard instead of dissipating uselessly in the case parts, which are inefficient radiators of sound. " the rim is normally made by laminating flexible strips of hardwood to the desired shape, a system that was developed by theodore steinway in 1880. the thick wooden braces at the bottom ( grands ) or back ( uprights ) of the piano are not as acoustically important as the rim, and are often made of a softwood, even in top - quality pianos, in order to save weight. the requirement of structural strength, fulfilled with stout hardwood and thick metal, makes a piano heavy ; even a small upright can weigh 136 kg ( 300 lb ), and the steinway concert grand ( model d ) weighs 480 kg ( 990 lb ). the largest piano built, the fazioli f308, weighs 691 kg ( 1520 lb ). the pinblock, which holds the tuning pins in place, is another area of the piano where toughness is important. it is made of hardwood, ( often maple ) and generally is laminated ( built of multiple layers ) for additional strength and gripping power. piano


, which holds the tuning pins in place, is another area of the piano where toughness is important. it is made of hardwood, ( often maple ) and generally is laminated ( built of multiple layers ) for additional strength and gripping power. piano strings ( also called piano wire ), which must endure years of extreme tension and hard blows, are made of high quality steel. they are manufactured to vary as little as possible in diameter, since all deviations from uniformity introduce tonal distortion. the bass strings of a piano are made of a steel core wrapped with copper wire, to increase their mass whilst retaining flexibility. the plate, or metal frame, of a piano is usually made of cast iron. it is advantageous for the plate to be quite massive. since the strings are attached to the plate at one end, any vibrations transmitted to the plate will result in loss of energy to the desired ( efficient ) channel of sound transmission, namely the bridge and the soundboard. some manufacturers now use cast steel in their plates, for greater strength. the casting of the plate is a delicate art, since the dimensions are crucial and the iron shrinks by about one percent during cooling. the inclusion in a piano of an extremely large piece of metal is potentially an aesthetic handicap, which piano makers overcome by polishing, painting and decorating the plate. plates often include the manufacturer ' s ornamental medallion and can be strikingly attractive. in an effort to make pianos lighter, alcoa worked with winter and company piano manufacturers to make pianos using an aluminum plate during the 1940s. the use of aluminum for piano plates, however, did not become widely accepted and was discontinued. the numerous grand parts and upright parts of a piano action are generally hardwood ( e. g. maple, beech. hornbeam ). however, since world war ii, plastics have become available. early plastics were incorporated into some pianos in the late 1940s and 1950s, but proved disastrous because they crystallized and lost their strength after only a few decades of use. the steinway firm once incorporated teflon, a synthetic material developed by dupont, for some grand action parts in place of cloth, but ultimately abandoned the experiment due to an inherent " clicking " which invariably developed over time. ( also teflon is " humidity stable " whereas the wood adjacent to the teflon will swell and shrink with humidity changes, causing problems. ) more recently, the kawai firm has built pianos with action parts made of more modern and effective plastics such as carbon fiber ; these parts have held


whereas the wood adjacent to the teflon will swell and shrink with humidity changes, causing problems. ) more recently, the kawai firm has built pianos with action parts made of more modern and effective plastics such as carbon fiber ; these parts have held up better and have generally received the respect of piano technicians. the part of the piano where materials probably matter more than anywhere else is the soundboard. in quality pianos, this is made of solid spruce ( that is, spruce boards glued together at their edges ). spruce is chosen for its high ratio of strength to weight. the best piano makers use close - grained, quarter - sawn, defect - free spruce, and make sure that it has been carefully dried over a long period of time before making it into soundboards. in cheap pianos, the soundboard is often made of plywood. piano keys are generally made of spruce or basswood, for lightness. spruce is normally used in high - quality pianos. traditionally, the black keys were made from ebony and the white keys were covered with strips of ivory, but since ivory - yielding species are now endangered and protected by treaty, plastics are now almost exclusively used. also, ivory tends to chip more easily than plastic. legal ivory can still be obtained in limited quantities. the yamaha firm invented a plastic called " ivorine " or " ivorite " that mimics the look and feel of ivory ; it has since been imitated by other makers. care and maintenance pianos need regular tuning to keep them up to pitch, which is usually the internationally recognized standard concert pitch of a4 = 440 hz. the hammers of pianos are voiced to compensate for gradual hardening, and other parts also need periodic regulation. aged and worn pianos can be rebuilt or reconditioned. often, by replacing a great number of their parts, they can be made to perform as well as new pianos. older pianos are often more settled and produce a warmer tone. piano moving should be done by trained piano movers using adequate manpower and the correct equipment for any particular piano ' s size and weight. pianos are heavy yet delicate instruments. over the years, professional piano movers have developed special techniques for transporting both grands and uprights which prevent damage to the case and to the piano ' s mechanics. the piano is a crucial instrument in western classical music, jazz, film, television, and most other complex western musical genres. since a large number of composers are proficient pianists a€ “ and because the piano keyboard offers an easy means of complex melodic


the true smut fungirobert bauer, dominik begerow, and franz oberwinkler this tree diagram shows the relationships between several groups of organisms. the root of the current tree connects the organisms featured in this tree to their containing group and the rest of the tree of life. the basal branching point in the tree represents the ancestor of the other groups in the tree. this ancestor diversified over time into several descendent subgroups, which are represented as internal nodes and terminal taxa to the right. you can click on the root to travel down the tree of life all the way to the root of all life, and you can click on the names of descendent subgroups to travel up the tree of life all the way to individual species. close box note : the classification of ustilaginomycotina is being revised. the tree at the top of this page reflects the current classification, whereas the following tree and the text on this page reflect a prior classification. the class ustilaginomycetes comprises more than 1400 species of basidiomycetous plant parasites, which are distributed in approximately 70 genera. they occur throughout the world, although many species are restricted to tropical, temperate or arctic regions. some species of ustilago and tilletia, e. g. the barley, wheat or maize smut fungi, are well known because they are of economic importance. for example, from 1983 to 1988 the barley smut fungi reduced annual yields by 0. 7 % to 1. 6 % in the prairie provinces in central canada, causing average annual losses of about u. s. $ 8, 000, 000 ( thomas 1989 ). tilletia contraversa is important in the international wheat trade ( trione 1982 ), and 2 - 5 % of the plants in a corn field are generally infected by ustilago maydis, while up to 80 % of a field can be infected if conditions are good for the smut fungus. on the other hand, the galls of u. maydis are considered a delicacy in the mesoamerican tradition. they are known in mexico as " huitlacoche " and in the u. s. a. as " maize mushroom ", " mexican truffles " or " caviar azteca " ( valverde et al. 1995 ). - plant parasitism - cellular interaction with primary interactive vesicles - cell wall carbohydrate composition with dominance of glucose and absence of xylose - 5s


host cell wall ( between the two arrows ) and the deposit at the host cell. scale bar = 1 µm. © r. bauer 1997 the contents of these vesicles ( fig. 1 ) are transferred to the host plasma membrane ( fig. 2 ). two major types are recognized. ( i ) local interaction zones ( fig. 3 ) : short - term production of primary interactive vesicles per interaction site results in local interaction zones, and ( ii ) enlarged interaction zones ( fig. 4 ) : continuous production and exocytosis of primary interactive vesicles results in the continuous deposition of fungal material at the whole contact area with the host cell. fig. 3. transmission electron micrograph showing a local interaction zone ( arrows ) between exobasidium pachysporum ( lower cell ) and its host ( upper cell ). note the interaction apparatus ( arrowheads ) and the deposit at the host cell. scale bar = 0. 5 µm. © r. bauer 1997 fig. 4. transmission electron micrograph showing an enlarged interaction zone between ustacystis waldsteiniae and its host. the haustorium ( h ) is encased by electron - opaque material. scale bar = 2 µm. © r. bauer 1997 cell wall carbohydrate composition prillinger et al. ( 1993 ) distinguished between several types of cell wall carbohydrate composition within the basidiomycota. the ustilaginomycetes have a distinctive type with dominance of glucose and absence of xylose that separates them from the urediniomycetes and hymenomycetes. gottschalk and blanz ( 1985 ) distinguished between a type a and a type b secondary structure of the 5s rrna. the ustilaginomycetes share the type b secondary structure with the hymenomycetes. in contrast with the hymenomycetes, the septal pores of the ustilaginomycetes are without multilayered parenthesomes. in contrast with the urediniomycetes, in most ustilaginomycetes the septal pores are enclosed by distinctive, tripartite membrane caps or discs ( bauer et al. 1995b, bauer et al. 1997, fig. 5 ). fig. 5. transmission electron micrograph showing a typical septal pore apparatus of the ustilaginomycetes ( entyloma callitrichis ) with two membrane


like the terms agaric, polypore, lichen etc. the term smut fungus circumscribes the organization and life strategy of a fungus, but it is not a taxonomic term. fungi that look superficially similar to the teliospore - forming members of the ustilaginomycetes evolved in different fungal groups, e. g. the microbotryales in the uredinomycetes ( bauer et al. 1997 ) or schroeteria in the ascomycota ( nagler et al. 1989 ). bauer, r., mendgen, k. and oberwinkler, f. 1995a. cellular interaction of the smut fungus ustacystis waldsteiniae. can. j. bot. 73 : 867 - 883. bauer, r., mendgen, k., and oberwinkler, f. 1995b. septal pore apparatus of the smut ustacystis waldsteiniae. mycologia 87 : 18 - 24. bauer, r., oberwinkler, f. and vanky, k. 1997. ultrastructural markers and systematics in smut fungi and allied taxa. can. j. bot. 75 : 1273 - 1314 begerow, d., bauer, r. and oberwinkler, f. 1997. phylogenetic studies on nuclear large subunit ribosomal dna sequences of smut fungi and related taxa. can. j. bot. 75 : ( appears in dec. ) berres, m. a., szabo, l. j. and mclaughlin, d. j. 1995. phylogenetic relationships in auriculariaceous basidiomycetes based on 25s ribosomal dna sequences. mycologia 87 : 821 - 840. duran, r. 1973. ustilaginales. in : ainsworth, g. c., sparrow, f. k. and sussman, a. s. ( eds. ) the fungi, vol 4b. academic press, new york, london, pp 281 - 300. gottschalk, m. and blanz, p. a. 1985. untersuchungen an 5s ribosomalen ribonucleinsauren als beitrag zur klarung von systematik und phylogenie der basidiomyceten. z. mycol. 51 : 205 - 243. kreise


sci. nat. bot. 3 : 12 - 127. valverde, m. e., paredes - lopes, o., pataky, j. k. and guevara - lara, f. 1995. huitlacoche ( ustilago maydis ) as a food source - biology, composition, and production. crc crit. rev. food sci. nutr. 35 : 191 - 229. vanky, k. 1987. illustrated genera of smut fungi. cryptogamic studies 1 : 1 - 159. many thanks to dr. meike piepenbring, dr. jose p. sampaio and michael weiß for their helpful comments. universitat tubingen, tubingen, germany universitat tubingen, germany correspondence regarding this page should be directed to robert bauer at page : tree of life ustilaginomycotina authored by. the true smut fungi. robert bauer, dominik begerow, and franz oberwinkler. the text of this page is licensed under the creative commons attribution license - version 3. 0. note that images and other media featured on this page are each governed by their own license, and they may or may not be available for reuse. click on an image or a media link to access the media data window, which provides the relevant licensing information. for the general terms and conditions of tol material reuse and redistribution, please see the tree of life copyright policies. - first online 26 november 1997 - content changed 23 january 2008 citing this page : bauer, robert, dominik begerow, and franz oberwinkler. 2008. ustilaginomycotina http : / / tolweb. org / ustilaginomycotina / 20530 / 2008. 01. 23 in the tree of life web project, http : / / tolweb. org /. the true smut fungi. version 23 january 2008 ( under construction ).


the definition of physical aggression varies from professional to professional. some do not distinguish between aggression directed against objects ( more accurately characterized as " property destruction " ), aggression directed against the self ( more accurately characterized as " self - injurious " behavior ) and aggression directed against others through verbal means ( more accurately characterized as " verbal aggression " ). although the definition of physical aggression may be more or less inclusive of these various behavioral anomalies, several intervention principles are common in addressing aggressive behavior : an immediate limit - setting response is necessary. it is inappropriate to " ignore " aggression, especially if someone is being injured. the immediate limit - setting response must not be reinforcing – if the child wants to leave the room, and you take the child out of the room when he behaves aggressively, then you ’ ve effectively reinforced aggression. it may not be possible, or legally permissible, for the treatment provider to implement " contingent exclusion " without the assistance of the adult caretaker. regulations regarding the use of physical restraint vary from location to location. physical restraint ( holding the child to prevent movement ) is not recommended by most professionals, may jeopardize the health and safety of the child, and may be illegal, depending upon its implementation. the use of physical guidance, physical prompting or other means of redirecting ( moving ) the child to a less - stimulating or less - dangerous setting is usually permissible, but it is always preferable to redirect the child through the use of verbal means. this depends upon the existence of rapport between the child and the treatment provider. the treatment provider is always " icing on somebody else ’ s cake. " in a school, the " cake " is the teacher or classroom aide. at home and in the community, the " cake " is the parent, adult babysitter, or other adult, who is responsible for the child ( daycare staff, etc ). when physical aggression occurs, it is almost always necessary to " get the cake involved " quickly. aggression is usually " the tactic of last resort, " when other modes of communication have failed. to reduce aggressive tendencies in children, it is almost always necessary to work on improving communication skills. to look further to see if having access to more than 500 treatment plans that worked may be helpful to you, see order here popularity : 100 % [? ]


students at plum school observe history, show gratitude by karen zapf published : wednesday, october 3, 2012, 9 : 30 p. m. updated : thursday, october 4, 2012 serving as a girl scout for the past several years, alexis mcclintock regularly volunteers in her community. mcclintock, 12, and other students at center elementary school in the plum school district, recently worked on a project that both helped those in need and taught them a history lesson. in honor of constitution day on sept. 17, the students wrote messages of inspiration on squares made of blue jean material. the squares are sewn together into quilts. the four freedom gratitude quilts are sent to injured and sick troops overseas as part of operation quiet comfort. constitution day commemorates the signing of the u. s. constitution on sept. 17, 1787. margi mcclintock, alexis mcclintock ' s mother, said she found out about operation quiet comfort when she was looking for a service project for her daughter ' s girl scout troop. mcclintock mentioned the project to jeff hadley, center elementary principal, who saw operation quiet comfort as an appropriate history lesson. hadley said public schools across the country conduct history lessons on constitution day — formerly citizenship day. “ it was felt that kids were losing some understanding of history and how the constitution came to be and how the country got started, ” hadley said. hadley said writing messages to the troops helps children make the connection between the fight for freedom more than 200 years ago and today. “ it ' s not just about reflecting on the past, ” hadley said. “ it ' s about making the connection that we still stand for the principles and beliefs that are the foundation of our country. ” margi mcclintock said each quilt is made up of 96 squares. center elementary, with 400 students, made enough squares for four quilts. alexis mcclintock, a sixth - grader, hopes the quilt will brighten an injured soldier ' s day. “ i wrote ‘ we miss you, and god bless you, ' ” she said. “ it felt really good to know that when they want to have some cheering up, they will have the quilts. ” amber delahunty, 12, appreciates the sacrifices the troops make. “ i think it ' s a good way to show how much we appreciate the troops and how they protect our country, ” said delahunty, also a sixth - grader. “ i wrote, ‘ you are a hero to us. ' ” alexis


think it ' s a good way to show how much we appreciate the troops and how they protect our country, ” said delahunty, also a sixth - grader. “ i wrote, ‘ you are a hero to us. ' ” alexis mcclintock would like to hear from the soldier who receives the quilt. “ i would love to get a message and see what they say about the quilt and how well we did, ” she said. hadley said the lesson was valuable because students got to send their personal messages to the injured soldiers. “ most importantly, the students took the opportunity to say ‘ thank you, ' ” hadley said. karen zapf is a staff writer for trib total media. she can be reached at 412 - 856 - 7400, ext. 8753, or email @ example. com. - nhl insider : penguins ’ shero seems ready to move letang - highmark to extend self - insurance plans to small businesses - steelers rookie safety thomas learning from polamalu, clark - cheswick council agrees to buy firetruck - police find burglary suspect ’ s cellphone at crime scene - united makes mileageplus status harder to achieve - sec investigation to continue into ‘ suspicious ’ acquisition of heinz stock option - it ’ s about what you can bring - more choose to buy into jobs - pirates notebook : beanballs escalate tension against reds - chrysler agrees to recall of jeeps at risk of fire ; ex - coal official seeks leniency in conspiracy case ; smithfield foods lays off 120 more at va. plant ; more you must be signed in to add comments to comment, click the sign in or sign up at the very top of this page. subscribe today! click here for our subscription offers.


the diagnosis of prostate cancer usually begins in your doctor ’ s office during a routine rectal exam followed by a blood test to measure prostate specific antigen ( psa ). if your rectal exam shows abnormal changes or your psa test is elevated, your doctor will need to do further testing to determine if you have cancer, benign prostatic hypertrophy, an infection, or some other condition. your doctor will ask about your medical history, including information about possible risk factors related to prostate cancer, and do a physical exam. your doctor will also do testing to determine the nature of the abnormal cell growth of the prostate. tests may include the following : - blood tests — your doctor will take a blood sample to test for prostatic specific antigen ( psa ). this is a chemical that indicates abnormalities in the prostate. - transrectal ultrasonography ( or ultrasound ) — an ultrasound probe is placed into the rectum as close to the prostate as possible. the probe releases painless sound waves that bounce off the inner tissues of the prostate. the echoes produced by the sound waves create a picture on a computer screen that helps distinguish normal prostate tissue from cancerous tissue. - transrectal biopsy — the biopsy sample is obtained by inserting a needle through the wall of the rectum into the prostate gland. transrectal ultrasound is used to guide the doctor in placing the needle into the prostate. the area of the biopsy is usually numbed. this procedure typically takes 10 - 20 minutes and is performed in the doctor ’ s office. if cancer is found in the biopsy sample, prognosis and treatment will primarily depend on : - stage of the cancer - psa value - your general health staging is a careful attempt to determine the extent and seriousness of the cancer by taking into account the following factors : - gleason score — a measure of the aggessiveness of the cancer as seen under the microscope tnm staging system : - tumor size and local spread ( t ) - spread to lymph nodes in the area ( n ) - spread or metastasis to distant organs ( m ) in addition to a physical exam, tests used to stage prostate cancer include : - urine and blood tests - additional physical exam - x - ray — a test that uses radiation to take a picture of structures inside the body, including lungs, bladder, kidney, and lymph nodes - bone scan — a nuclear medicine scan that uses radioactive material injected into your body to detect abnormal areas of bone. this


test that uses radiation to take a picture of structures inside the body, including lungs, bladder, kidney, and lymph nodes - bone scan — a nuclear medicine scan that uses radioactive material injected into your body to detect abnormal areas of bone. this is usually not done unless your psa is above 10 ng / ml or you have bone pain. - ct or cat scan — a type of x - ray that uses a computer to make pictures of structures inside the body - prostascint scan — a nuclear medicine scan that uses radioactive material injected into your body to detect prostate cells that may have traveled outside of the prostate. this study is still investigational and has not yet been proven to change disease management. - mri scan — a test that uses magnetic waves to make pictures of structures inside the body - lymph node biopsy — tissue samples are taken from the lymph nodes surrounding the prostate and sent to the laboratory for examination. the tnm staging system is often used to classify cancer of the prostate. the gleason score is often combined with the tnm system to predict the likelihood of survival over the next five years with treatment. the higher the numbers the worse the prognosis. tumor size and local spread ( t ) : - t0 : there is no evidence of tumor. - t1 : the cancer is not felt during a rectal exam nor seen by ultrasound. it is usually found during treatment for benign prostatic hypertrophy or during evaluation of an elevated psa test. - t2 : the cancer can be felt during rectal exam, but is confined to the prostate. - t3 : the cancer has spread just outside the prostate and may involve the seminal vesicles. - t4 : the cancer has spread to local tissues beyond the prostate and seminal vesicles, organs, or lymph nodes. spread to lymph nodes ( n ) : - n0 : there is no evidence of cancer in any lymph node. - n1 : cancer has spread to one nearby lymph node that is < 2 cm in size. - n2 : cancer has spread to one nearby lymph node 2 - 5 cm in size or multiple lymph nodes all < 5 cm in size - n3 : cancer has spread to any nearby lymph nodes > 5 cm in size. spread to distant organs ( m ) : - m0 : there is no evidence of distant spread. - m1 : there is no distant spread to far removed lymph nodes,


( cnn ) - - human concepts of beauty are shaping conservation efforts, protecting good - looking plants and animals over ugly ones, a study suggests. the report, " the new noah ' s ark : beautiful and useful species only, " has been published in the 2012 edition of the scientific journal, biodiversity. it describes how vulnerable species that overtly display characteristics human beings respect or find desirable - - such as beauty, strength, power or cuddliness - - are more likely to be the focus of concerted conservation programs than animals or plants that are less appealing to the eye. " people have biases towards species that are glamorous, " said dr. ernie small, author of the study and taxonomist for agriculture canada. " animals that are beautiful, entertaining or that command respect due to their size or power are almost always given greater forms of conservation protection. " the study highlights charismatic mega - fauna such as whales, tigers and polar bears as animals more likely to be the focus of successful conservation programs, protective legislation and public funding drives. as a result, the plight of less glamorous - - but no less ecologically important organisms, such as snakes, spiders and frogs - - are often ignored. small argues that this focus on large, spectacular species could have profound consequences for a wide variety of finely balanced ecosystems and food chains. " when you concentrate on the preservation of selective species... you do an inadequate job of protecting biodiversity as a whole, " he said.. he adds that by employing such selective methods human beings could also be manufacturing nature to reflect their own image or the characteristics they admire. " we find attractive in animals the same qualities that we find attractive largely in our own species. these are not always the most ecologically important species however, " he added. for those working on the front line of conservation, the concerns raised by small and his study are very real. according to dr sybille klenzendorf, director of world wildlife fund ' s species program, there is already a wide body of evidence that suggests people are most interested in vulnerable animals that most closely resemble human beings - - usually large mammals with forward - facing eyes. but klenzendorf argues that focusing conservation efforts on these vulnerable species can lead to the best conservation programs. " these large, charismatic species are... the ones that require the largest amount of wild habitat, and by preserving them we save the less impressive species too, " said klenzendorf. " in order to ensure the survival of wild tigers,


vegan for life by jack norris, rd & ginny messina, mph, rd can a natural diet require supplements? by jack norris, rd | last updated : march 2012 if we admit that vegans need to get vitamin b12 through fortified foods or supplements, are we saying that a vegan diet is unnatural? one point to consider is that feces contain large amounts of vitamin b12, produced by bacteria in the colon, and that if we found ourselves in a state of nature, and still wanted to be vegan, we could get enough b12 from feces, though it would be important to make efforts to make sure the bacteria were killed and viruses were neutralized. admittedly, that ' s not terribly appetizing. people have told me that they and other vegans they know do not take vitamin b12 supplements nor eat fortified foods and are healthy. while many vegans do not supplement with b12 and remain apparently healthy for many years, they normally do not know what their homocysteine levels are, which could eventually contribute to stroke or dementia. they might eventually run into overt b12 deficiency ( see individual cases of deficiency ). you are taking a real chance by assuming you have transcended the need for a recommended b12 intake. as people live longer, homocysteine has more years to cause damage to the body. because of this, the importance of b12 has increased. the longer a vegan does not supplement with b12, the lower their active b12 levels will drop, increasing their homocysteine levels. in western society today, it is easy for vegans to ensure an adequate b12 intake. vegans who supplement with b12 can have superior b12 status to non - vegetarians who do not supplement. in fact, due to a decrease in the ability to absorb b12 from animal foods as people age, the food and nutrition board says that all people ( not just vegans ) over age 50 should " meet their rda mainly by consuming foods fortified with b12 or a b12 - containing supplement. " is the vegan diet natural? to answer that question, i recommend an article that examines the subject in great detail, comparative anatomy and physiology brought up to date : are humans natural frugivores / vegetarians, or omnivores / faunivores? by tom billings. after an extensive review of the research, billings concludes that humans are not naturally vegetarians or vegans. despite this, he says : i am both


rather questionable. today ' s commercial plant foods and meats are different from the foods available in prehistoric times. we eat hybrids of plants and we feed foods to farmed animals that they would not normally eat. farmed animals are typically given a host of supplements in their feed. the u. s. food supply is routinely fortified with a host of vitamins and minerals ( such as vitamin d in milk ), and most people who turn to what they consider to be a more natural diet as adults have often benefited from this supplementation. in the last two hundred years, nutritional science has solved all sorts of serious health problems that plagued humanity for eons. although there are exceptions, eating meat is one of the few things which most people try to do that is " natural. " paleolithic dieters are probably the most vocal anti - vegetarian, natural eaters. yet they rarely eat insects, grubs, and worms which, according to paleoveganology in his post what, no bugs?!, " have long provided humans and other primates with nutrients, and continue doing so today in most parts of the world. " so one has to wonder how close to nature they are actually trying to eat. many vegans are understandably skeptical of the medical and scientific community. but by refusing to accept the scientific evidence in favor of the need to supplement with b12, we provide a steady flow of vegans with health issues for the medical community to study. if you are wary of the medical community, the best thing you can do is ensure that you do not develop b12 deficiency and become one of their subjects. while i ' m grateful that research has been done on vegans who do not supplement with b12, enough is enough. it is the vegan community ' s responsibility to stop this flow of research subjects. when researchers decide to do studies examining the health problems of vegans who do not supplement their diets with b12, it would be best if they simply could not find any. all vegan advocates should be aware of the symptoms of b12 deficiency ( with the realization that elevated homocysteine levels occur long before these symptoms are noticeable ), and the need for new vegans to start supplementing with b12 shortly after becoming vegan ( or even near - vegan ).


this article describes the design of an antenna for " local " contacts on 7mhz, including a simple and efficient matching system that presents a 50ω load to the transmitter. the design objectives are : the antenna is intended to serve mainly local vk contacts. the requirement can be simply met by an antenna with approximately omni - directional characteristics. even though the location is a semi rural one, a horizontal antenna is chosen for best noise performance. vk1od is located in bowral ( abouty 100km sw of sydney ), roughly in the centre of the south east corner of australia where well over half of australia ' s population reside, as illustrated in the map to the right. the table shows the nearby state capital cities ( 2002 ) and the path parameters for 7mhz communications at 0500 utc with ssn = 100. note that radiation angles from 31 to 82 degrees suit these cities. a dipole mounted low to the ground with its legs sloped downwards from the centre was chosen as a reasonably omni - directional horizontal antenna. a mast to support the centre of the dipole at a height of 11m is available, and the legs can be conveniently sloped downwards at about 45° to the horizontal. the impedance of a nominally half wave dipole is quite dependent on frequency, height above ground, the nature of ground, and nearby conductors. the series resistance component changes slowly with about resonance, and reactance changes quite quickly with frequency. fig 1 shows nec modelled r and x for the antenna which is resonant at as the frequency increases, the change in feed point impedance can be expressed as the vswr it would cause on a given feedline. fig 2 shows the vswr in a 75ω line. conversely, as the length of the antenna is increased beyond resonance at a given frequency, vswr ( 75 ) will increase. the objective of the matching scheme used is to cause a vswr of 1. 5 on the 75ω feedline because the effect of that vswr is that there will be points along the feedline where the the ratio of v to i, the impedance, is 50ω purely resistive. in the strictest sense, we want vswr = 1. 5 at the transmitter end of the 75ω line, vswr will be a little higher at the feed point end due to line losses. first step is to erect the dipole with 1 : 1 current balun at the feed point and tune it to obtain vswr = 1. 5 in


line, vswr will be a little higher at the feed point end due to line losses. first step is to erect the dipole with 1 : 1 current balun at the feed point and tune it to obtain vswr = 1. 5 in the 75ω feed line at the desired frequency by making it a little longer than a resonant dipole. this is best done by measuring vswr with a 75ω swr meter at the transmitter end of a a feed line length that is a little longer than anticipated for the installation ( see below ). fig 3 shows the feed point impedance that would be transformed by a length of belden 1189a ( rg6 ) at 7. 1mhz. the nec model give above gives specific values for feed point impedance for the modelled antennas, but the installed antenna will depart from the model to some extent because the model is a simple one that does not capture the entire antenna environment, and some parameters ( eg soil type ) are guesses and have a certain amount of error. nevertheless, we can use the model to guide us to a solution that is tuned for the actual installation. we expect that a dipole like that described above, when tuned for vswr = 1. 5 in a 75ω feed line will have a feed point resistance component typically somewhere in the range 60ω to 80ω. from fig 3, select a length of line that is convenient and will suit that resistance range with positive x ( since the dipole is resonant below the desired frequency ). fig 3 indicates a length of around 13m will suit, lets choose 15m as a starting point to cover that range. now, connect a 50ω line from the transmitter to a 50ω swr meter and then to the 15m of 75ω line. measure vswr ( 50 ) at the desired operating frequency, and at adjacent frequencies. it is likely that the vswr is greater than one, and is less at lower frequencies. cut a little off the 75ω line, and repeat the measurements. repeat the process until the vswr ( 50 ) minimum is at the desired frequency, and it should be very low, less than 1. 1. fig 4 shows the measured vswr, rx and xs from 6mhz to 8mhz looking into the tuned length of rg6. apologies for the graphs, the tapr vna software is poor. the red vswr scale is from 1 : 1 to 3 : 1, so the second


##mhz to 8mhz looking into the tuned length of rg6. apologies for the graphs, the tapr vna software is poor. the red vswr scale is from 1 : 1 to 3 : 1, so the second grid line from the bottom is 1. 4 : 1. the blue line is r and scale is 0 to 100, and orange line is x and scale is - 50 to + 50. note that the r and x lines in fig 4 are not directly comparable with fig 3 ( fig 3 shows the feed point impedance required for input impedance of 50 + j0ω vs length, whereas fig 4 shows the input impedance with the optimised tuned length of feed line ). whilst it is possible to adjust the dipole length and feedline line length for a perfect match, it is impractical as factors like variations in soil moisture content after rain, seasonal variation in vegetation etc will cause small variation in the input impedance. the dipole could be tuned so that resonance is above the desired frequency and vswr ( 75 ) = 1. 5 at the desired frequency by shortening it from resonant length. this means that feed point impedance would typically be in the range 60ω to 80ω and reactance is negative. looking at fig 3, you might choose a line length of 23m as the starting point and then adjust the line length until vswr ( 50 ) looking into the line is very low ( < 1. 1 ). fig 5 shows the feed point detail. the rg6 feed line is inside a length of 13mm irrigation pipe as protection from birds, and a w2du style balun formed of 12 suppression sleeves on the rg6 fits inside the irrigation pipe. fig 6 shows an adjustable capacity hat for fine tuning the antenna. it is just a piece of hdc with a dog leg in the middle, and secured to the dipole wire with a split bolt line tap about 900mm from the end. fig 7 shows the insulator termination detail. the copper is terminated using crimp sleeves particular to the purpose. these were widely used on open wire telephone lines, but probably not obtainable now. fig 8 shows the method of tensioning the dipole. the star picket is a temporary measure and will be replaced with a length of galvanised steel pipe. the winch fitting is a rural fence accessory. fig 8 shows the earthing of the supporting mast to a 2. 4m long 16mm copper clad ground rod


a temporary measure and will be replaced with a length of galvanised steel pipe. the winch fitting is a rural fence accessory. fig 8 shows the earthing of the supporting mast to a 2. 4m long 16mm copper clad ground rod driven into wet clay. two 25mm2 conductors bond the mast to the earth rod. the ground rod consistently measures around 12ω resistance indicating a soil resistivity of around 20ωm ( which is quite low ). when connected to the mast in its foundation, the combined resistance consistently measures 9ω to 10ω. the temporary end supports were replaced with 50mm diameter steel posts. this raised the ends of the dipole to about 7m in height ( included angle 135° ) and required a small adjustment in tuning. fig 10 shows the end support posts. they are made from 40mm nb ( ~ 50mm od ) galvanised steel pipe, with cap added and a chain link welded on for rigging attachment. the winch pictured is a permanent fence wire strainer which cost about $ 7 at the local rural hardware shop. the other pics show the lateral guys ( 4mm galvanised fswr ) on the mast at 8m height, and their attachment to an eye in the roof frame and a star picket driven into the ground. the mast was trued up laterally using a theodolite and then the rigging screws and shackle pins wired to prevent loosening. the egg insulators are to prevent unwanted interaction with the dipole. fig 11 above shows a scan with a aimuhf antenna analyser look into the existing 13m of rg6 coax. the capacity loading stingers were adjusted in position to obtain vswr ( 75 ) = 1. 5 at about 7. 070mhz. the vswr lot above is referenced to 75ω, and the cyan cursor shows vswr ( 75 ) = 1. 5 at 7. 059mhz. this is quite close enough, antenna tuning will change a little with ground moisture level etc. in this case, the stingers needed to be move about 100mm to compensate for the new end height which could be expected to affect feed point reactance much more than resistance. having used this stinger design for many years, it was time to improve the design. fig 12 shows the improved design, the 2mm hdc stinger wire is formed around a 6mm round rod, then through the split bolt line tap, and the


this stinger design for many years, it was time to improve the design. fig 12 shows the improved design, the 2mm hdc stinger wire is formed around a 6mm round rod, then through the split bolt line tap, and the ends bent out at 90°. the improved stinger seats better against the main line, won ' t fall out easily, and can be removed without fully undoing the line tap. next step is to determine any adjustment needed in the tuned 75ω coax section. fig 13 above shows the same scan referenced to 50ω. minimum vswr ( 50 ) occurs at 7. 060mhz, and as expected, it is quite low ( 1. 04 ). it is not altogether surprising that the existing length of line remains optimal as the retuning with the stingers was mostly to correct a shift in reactance caused by the new mounting height. note that in fig 13, minimum vswr is extremely low ( < 1. 05 ), and reactance does not pass through zero around minimum vswr. this is an example that shows the nonsense of the widely held belief that system resonance is synonomous with minimum vswr, and that reactance always passes through zero coincident exactly with minimum vswr. fig 14 above shows the new cable entry panel. a brick was removed from the wall and an aluminium panel folded up to cover the space and accommodate four n type bulkhead connectors. this is the garage wall, and the inside is unlined which gives ready access to the other side of the connectors. fig 15 shows a pair of ceramic feed through insulators with metal hardware fabricated from 5mm stainless threaded rod, nuts and washers. the feed through insulators are to facilitate entry of an open wire feeder. the panel is grounded via a 6mm ^ 2 conductor behind the wall. the 13m of rg6 feedline has a loss under the mismatched conditions of 0. 22db and cost a $ 5. another 2m of rg58 fly lead to make the distance to the transmitter has a loss of 0. 07db at a cost of less than a $ 2, giving a total feed line system with loss of 0. 3 db ( efficiency 93 % ) for less than a $ 7 and delivering a very good match for the transmitter. the balun is about a $ 10, so all up, the antenna cost is about a $ 17 plus appropriate copper wire. an nec model of the dipole indicates copper loss of


past flood events | 2011 2011 proved to be another record - breaking flood year in the united states. usgs personnel from north dakota to louisiana were busy measuring spring floods on the red river of the north, the ohio river, the mississippi river, and many tributaries. water science centers along the missouri river and its tributaries saw record - breaking snow - melt runoff through the summer. the following link outlines some of the nation - wide efforts of the usgs to study and document these record - breaking floods : focal points of spring / summer floods in the central us : summary information for 2011 floods usgs professional paper 1798 : 2011 floods of the central united states : summary - flood information sheet : science efforts of the u. s. geological survey chapter b - general weather conditions and precipitation chapter c - peak streamflows and runoff volumes chapter e - new madrid floodway stages and streamflows other chapters coming soon... video : the anatomy of floods : the causes and development of 2011 ' s epic flood events 2011 service assessments from the national weather service divine providence - the 2011 flood in the mississippi river and tributaries project, by charles camillo ( usace, 2012 ) usace post 2011 flood event analysis of the missouri river mainstem flood control storage irtf report - interagency recovery task force website with 2011 - 12 report.


usgs surface water information new & noteworthy usgs in your state usgs water science centers are located in each state. other water sites documents are presented in portable document format ( pdf ) ; the latest version of adobe reader or similar software is required to view it. download the latest version of adobe reader, free of charge. summary of u. s. geological survey on - line instantaneous fluvial sediment and ancillary data by lisa m. turcios, john r. gray, and annette l. ledford instantaneous fluvial sediment data, in addition to other instantaneous water - quality and ancillary data collected by the u. s. geological survey ( usgs ), are available on - line through the national water information system world wide web ( nwisweb ) water - quality data base at http : / / waterdata. usgs. gov / nwis / qwdata. the nwisweb water - quality data base was populated and is periodically refreshed from electronic files maintained by individual usgs district offices across the united states and puerto rico. it represents the single largest repository of usgs electronic instantaneous - value suspended - sediment, bedload, and bed - material data. these web pages provide a summary of fluvial - sediment data by state, and by usgs station number retrieved from the then - under - construction nwisweb data base on january 13, 2000. the meta data can be accessed by following the links at the bottom of this web page. more than 2. 6 - million values of instantaneous - value sediment and ancillary data were retrieved for 15, 415 sites in all 50 states, puerto rico, and other locations, including canada, the federated states of micronesia, guam, and southern ryukyu islands, from the nwisweb data base on january 13, 2000. the nwisweb data base is described, along with the criteria used to retrieve sediment and ancillary data, and selected characteristics of those data in a report to be published in the proceedings of the 7th federal interagency sedimentation conference, reno, nevada, march 25 - 29, 2001. a copy of the report is available in pdf format and will require the use of adobe acrobat software to view. additional helpful information : > maps showing locations of sites in the united states and puerto rico with sediment and ancillary data retrieved from the nwisweb data base on january 13, 2000 : the results of the january 13, 2000,


view. additional helpful information : > maps showing locations of sites in the united states and puerto rico with sediment and ancillary data retrieved from the nwisweb data base on january 13, 2000 : the results of the january 13, 2000, retrieval from then - under - construction nwisweb water - quality data base, which are summarized in these web pages, do not include all instantaneous - value sediment and ancillary data collected by the usgs. only those data that were present in usgs district office nwis data bases in the spring of 1999 were used to populate the nwisweb data base that was the source of the january 13, 2000, retrieval. there is evidence that a considerable amount of usgs suspended - sediment concentration data and some bedload - transport data were not available on the nwisweb on january 13, 2000. in many cases, these data can be obtained through usgs district offices for a fraction of the cost of collecting a comparable amount of sediment and ancillary data. for more information, we recommend contacting the local usgs office for water resources by following the links available at http : / / water. usgs. gov / local _ offices. html. daily - value suspended - sediment data collected by the usgs from 1930 through september 30, 1994, are available to the public on - line at http : / / webserver. cr. usgs. gov / sediment /. these and subsequent daily - value usgs suspended - sediment data are entered into the nwisweb data base as the data become available. for more information about the data collected, you may follow this link to chapter 2. water - quality system of the user ' s manual for the national water information system of the u. s. geological survey. chose state to view summary pages. station data for each state may take minutes to load. suggestions for printing.


hidden vitamin in milk yields remarkable health benefits weill cornell researchers show tiny vitamin in milk, in high doses, makes mice leaner, faster and stronger new york ( june 14, 2012 ) — a novel form of vitamin b3 found in milk in small quantities produces remarkable health benefits in mice when high doses are administered, according to a new study conducted by researchers at weill cornell medical college and the polytechnic school in lausanne, switzerland. the findings, recently reported in the june 2012 issue of the journal, cell metabolism, reveal that high doses of the vitamin precursor, nicotinamide riboside ( nr ) — a cousin of niacin — prevent obesity in mice that are fed a fatty diet, and also increase muscle performance, improve energy expenditure and prevent diabetes development, all without side effects. the swiss researchers, led by dr. johan auwerx, performed the mouse experiments, while the ability to give the animals sufficient doses of nr was made possible by weill cornell medical college researchers, who played key roles in uncovering the biological story of nr. " this study is very important. it shows that in animals, the use of nr offers the health benefits of a low - calorie diet and exercise — without doing either one, " says dr. anthony sauve, associate professor of pharmacology at weill cornell medical college. dr. sauve is the pharmacologist and organic chemist who has invented a simple method for efficiently synthesizing nr in large scale. he was first to show that nr increases nicotinamide adenine dinucleotide ( nad ) levels in mammalian cells. nad is a central player in energy metabolism. he has pioneered research into the compound, and he is a leader in investigating how nad can signal adaptation in cells and in physiology. " the research also suggests that the effects of nr could be even broader, " dr. sauve says. " the bottom line is that nr improves the function of mitochondria, the cell ' s energy factories. mitochondrial decline is the hallmark of many diseases associated with aging, such as cancer and neurodegeneration, and nr supplementation boosts mitochondrial functioning. " the swiss researchers call nr a " hidden vitamin " that is believed to also be present in many other foods, although levels are low and difficult to measure. nevertheless, the effects of nr on metabolism " are nothing short of astonishing. " got nicotinamide riboside? the study depended on a series of crucial discoveries by dr. sauve and his laboratory colleagues.


are low and difficult to measure. nevertheless, the effects of nr on metabolism " are nothing short of astonishing. " got nicotinamide riboside? the study depended on a series of crucial discoveries by dr. sauve and his laboratory colleagues. nr, related to niacin and other common forms of vitamin b3, was first investigated more than 60 years ago by a stanford researcher and 1959 nobel laureate, arthur kornberg. but little more was known about its effects in mammals until dr. sauve discovered the effect nr had in stimulating levels of nad in mammalian cells — work he published in 2007. nad allows sugars, fats, and proteins to be converted into energy. dr. sauve ' s research provided the first evidence that nr enhances nad levels in the mitochondria in mammalian cells in culture. these findings are published in the current study. these cell - based observations were key to the demonstration that nr could stimulate tissue nad levels in animals, and that it could stimulate nad - dependent sirtuins, which adapt physiology to the low calorie diets that are known to extend the lifespan of many organisms. dr. sauve invented a relatively simple method for efficiently synthesizing nr in large scale so that its health benefits can be studied. this methodology, which makes it possible to make nr commercially available, was patented by cornell ' s center for technology enterprise and commercialization and subsequently licensed to chromadex corporation. the development of a means to synthesize nr in adequate quantities was crucial to the current research, and the sauve lab provided methods and nr to make the study possible. in addition, the biological observations on the effects of nr on nad levels in cells and on mitochondria were key to the study. finally, the sauve laboratory has developed state of the art analytical methods to determine nad levels in cells, tissues and organelles, and the laboratory provided several key metabolic measurements highlighted in the study. " our published scientific work has verified that nr is perhaps the most potent nad enhancing agent ever identified, " he says. his laboratory is also widely recognized for developing an expertise in the measurement of nad metabolism in cell tissues. with this compound, the swiss researchers found that mice on a high - fat diet supplemented with nr gained significantly less weight ( 60 percent ) than mice fed the same diet without nr, even though the mice supplemented with nr ate the same amount of food as mice on the high fat diet not treated with nr. they had improved energy. they were in better shape than


weight ( 60 percent ) than mice fed the same diet without nr, even though the mice supplemented with nr ate the same amount of food as mice on the high fat diet not treated with nr. they had improved energy. they were in better shape than the untreated mice, with significantly better endurance and stronger muscles. additionally, none of the treated mice developed diabetes, as seen in the untreated mice on the high fat diet. and when fed a normal diet, nr treated mice had improved sensitivity to insulin. the nr treated mice also showed lower cholesterol levels. all of these benefits came without toxicity. while the new study demonstrates that high doses of nr can largely prevent the negative health consequences of a poor diet in mice, dr. sauve stresses that the effects of high doses of the vitamin in humans have not been evaluated. " it is important to keep in mind that the amount of nr in milk and other foods appears to be small. we don ' t know what effects nr would have in humans at relatively high doses, " he says. " still, we have very encouraging evidence of benefits of nr and nad augmentation in general from this animal study — and much more work to do, " he says. the study ' s senior investigator dr. auwerx is head of laboratory of integrative systems physiology at the polytechnic school in lausanne ( ecole polytechnique federale de lausanne or epfl ) and the first author is dr. carles canto, also of epfl. other co - authors include dou y. youn and dr. yana cen from weill cornell medical college ; dr. riekelt h. houtkooper, dr. eija pirinen, dr. maaike h. oosterveer, dr. pablo j. fernandez - marcos, dr. hiroyasu yamamoto, dr. penelope a. andreux, dr. philippe cettour - rose, dr. kristina schoonjans and dr. chris rinsch from epfl ; dr. karl gademann from the university of basel in switzerland. the ellison medical foundation new scholar award and the new york state spinal cord injury board funded study contributions by the weill cornell medical college researchers. weill cornell medical college weill cornell medical college, cornell university ' s medical school located in new york city, is committed to excellence in research, teaching, patient care and the advancement of the art and science of medicine, locally, nationally and globally. physicians and


medical college weill cornell medical college, cornell university ' s medical school located in new york city, is committed to excellence in research, teaching, patient care and the advancement of the art and science of medicine, locally, nationally and globally. physicians and scientists of weill cornell medical college are engaged in cutting - edge research from bench to bedside, aimed at unlocking mysteries of the human body in health and sickness and toward developing new treatments and prevention strategies. in its commitment to global health and education, weill cornell has a strong presence in places such as qatar, tanzania, haiti, brazil, austria and turkey. through the historic weill cornell medical college in qatar, the medical college is the first in the u. s. to offer its m. d. degree overseas. weill cornell is the birthplace of many medical advances — including the development of the pap test for cervical cancer, the synthesis of penicillin, the first successful embryo - biopsy pregnancy and birth in the u. s., the first clinical trial of gene therapy for parkinson ' s disease, and most recently, the world ' s first successful use of deep brain stimulation to treat a minimally conscious brain - injured patient. weill cornell medical college is affiliated with newyork - presbyterian hospital, where its faculty provides comprehensive patient care at newyork - presbyterian hospital / weill cornell medical center. the medical college is also affiliated with the methodist hospital in houston. for more information, visit weill. cornell. edu.


the most common symptom of peripheral artery disease ( pad ) is pain and cramping in the legs, called intermittent claudication. if your legs cramp after walking short distances, your doctor may want to look for disease in the arteries that supply your legs. the physical exam usually consists of looking at your feet and feeling for pulses in your legs and feet. tests may include : - blood tests — your doctor will review your blood fats and / or your blood sugar. if either is elevated, it may be a treatable cause of pad. - ankle - brachial index — this is a blood pressure recordings in the legs and arms. - doppler ultrasonography — this is a small device that can detect blood flow using sound waves. the test is fast, painless, and harmless. - angiography — during this procedure, x - rays are taken while dye is being injected into the blood vessels. the x - rays can show blockages. this test is invasive and is usually only done in more serious cases. - ct angiography — this involves using ct scan technology along with angiography to show the blood vessels. - mri scan — magnetic waves are used to take images of the body. you will also be evaluated for accompanying problems, such as diabetes, high blood pressure, and elevated levels of cholesterol and other blood fats. - reviewer : michael j. fucci, do - review date : 09 / 2012 - - update date : 00 / 92 / 2012 -


foreign type specifiers here is a list of valid foreign type specifiers for use in accessing external objects. specifies an undefined return value. not allowed as argument type. as argument : any value ( # f is false ( zero ), anything else is true ( non - zero ). as result : anything different from 0 and the null pointer is # t. this type maps to int in both c and c + +. a signed or unsigned character. as an argument, the input scheme character is cast to c char or unsigned char, resulting in an 8 - bit value. a scheme character with an integer value outside 0 - 127 ( signed ) or 0 - 255 ( unsigned ) will be silently truncated to fit ; in other words, don ' t feed it utf - 8 data. as a return type, accepts any valid unicode code point ; the return type is treated as a c int, and converted to a scheme character. an 8 - bit integer value in range - 128 - 127 ( byte ) or 0 - 255 ( unsigned byte ). values are cast to and from c char or unsigned char type, so values outside this 8 - bit range will be unceremoniously truncated. [ type ] short a short integer number in 16 - bit range. maps to c short or unsigned short. [ type ] int an integer number in fixnum range ( - 1073741824 to 1073741823, i. e. 31 bit signed ). unsigned - int further restricts this range to 30 bit unsigned ( 0 to 1073741823 ). int maps to c type int and int32 maps to int32 _ t. as an argument type, these expect a fixnum value, and as a return type they return a fixnum. values outside the ranges prescribed above are silently truncated ; you should use e. g. integer if you need the full 32 - bit range. note : int32 is not recognized as an argument type prior to chicken 4. 7. 2. notes for 64 - bit architectures : - c ' s int is 32 bits on most 64 - bit systems ( lp64 ), so int and int32 are functionally ( if not semantically ) equivalent. - the fixnum type is larger than 32 bits and consequently the entire signed or unsigned 32 - bit range is available for this type on 64 - bit systems. however, for compatibility with 32 - bit systems it is probably unwise to rely on this. if you need a 32 - bit range, you


consequently the entire signed or unsigned 32 - bit range is available for this type on 64 - bit systems. however, for compatibility with 32 - bit systems it is probably unwise to rely on this. if you need a 32 - bit range, you should use ( unsigned ) integer or integer32. a fixnum or integral flonum, mapping to int or int32 _ t or their unsigned variants. when outside of fixnum range the value will overflow into a flonum. c ' s int is 32 bits on most 64 - bit systems ( lp64 ), so integer and integer32 are functionally ( if not semantically ) equivalent. [ type ] integer64 a fixnum or integral flonum, mapping to int64 _ t or uint64 _ t. when outside of fixnum range the value will overflow into a flonum. on a 32 - bit system, the effective precision of this type is 52 bits plus the sign bit, as it is stored in a double flonum. ( in other words, numbers between 2 ^ 52 and 2 ^ 64 - 1 can be represented but there are gaps in the sequence ; the same goes for their negative counterparts. ) on a 64 - bit system the range is 62 bits plus the sign bit, the maximum range of a fixnum. ( numbers between 2 ^ 62 and 2 ^ 64 - 1 have gaps. ) unsigned - integer64 is not valid as a return type until chicken 4. 6. 4. [ type ] long either a fixnum or a flonum in the range of an ( unsigned ) machine long. similar to integer32 on 32 - bit systems or integer64 on 64 - bit. [ type ] size _ t a direct mapping to c ' s size _ t. a floating - point number. if an exact integer is passed as an argument, then it is automatically converted to a float. [ type ] number a floating - point number. similar to double, but when used as a result type, then either an exact integer or a floating - point number is returned, depending on whether the result fits into an exact integer or not. a zero - terminated c string. the argument value # f is allowed and is passed as a null pointer ; similarly, a null pointer is returned as # f. note that the string contents are copied into ( automatically managed ) temporary storage with a zero byte appended when passed as an argument. also, a return value of this type is copied into garbage collected memory using strc


pointer is returned as # f. note that the string contents are copied into ( automatically managed ) temporary storage with a zero byte appended when passed as an argument. also, a return value of this type is copied into garbage collected memory using strcpy ( 3 ). for the nonnull - variant, passing # f will raise an exception, and returning a null pointer will result in undefined behavior ( e. g. a segfault ). [ type ] c - string * similar to c - string and nonnull - c - string, but if used as a result type, the pointer returned by the foreign code will be freed ( using the c library ' s free ( 3 ) ) after copying. this type specifier is not valid as a result type for callbacks defined with define - external. [ type ] unsigned - c - string same as c - string, nonnull - c - string, etc. but mapping to c ' s unsigned char * type. [ type ] c - string - list takes a pointer to an array of c strings terminated by a null pointer and returns a list of strings. the starred version c - string - list * also releases the storage of each string and the pointer array afterward using free ( 1 ). only valid as a result type, and can only be used with non - callback functions. [ type ] symbol a symbol, which will be passed to foreign code as a zero - terminated string. when declared as the result of foreign code, the result should be a string and a symbol with the same name will be interned in the symbol table ( and returned to the caller ). attempting to return a null string will raise an exception. a blob object, passed as a pointer to its contents. permitted only as argument type, not return type. arguments of type blob may optionally be # f, which is passed as a null pointer. for the nonnull - variant, passing a # f value will raise an exception. [ type ] u8vector a srfi - 4 number - vector object, passed as a pointer to its contents. these are allowed only as argument types, not as return types. the value # f is also allowed and is passed to c as a null pointer. for the nonnull - variants, passing # f will raise an exception. [ type ] ( c - pointer type ) [ type ] ( nonnull - c - pointer type ) an operating - system pointer or a locative


pointer. for the nonnull - variants, passing # f will raise an exception. [ type ] ( c - pointer type ) [ type ] ( nonnull - c - pointer type ) an operating - system pointer or a locative. c - pointer is untyped, whereas ( c - pointer type ) points to an object of foreign type type. the value # f is allowed and is passed to c as a null pointer ; similarly, null is returned as # f. for the two nonnull - variants, passing # f will raise an exception, and returning null will result in a null pointer object. ( note : it is still possible to deliberately pass a null pointer through a nonnull - c - pointer by manually creating a null pointer object, e. g. via ( address - > pointer 0 ). ) [ type ] pointer - vector a vector of foreign pointer objects ; see pointer vectors. permitted only as an argument type, not as return type. this type was introduced in chicken 4. 6. 3. a pointer vector contains a c array of void pointers, and the argument is passed as a void * * pointer to these contents. just as for bytevector types, you must somehow communicate the length of this array to the callee ; there is no sentinel node or null terminator. # f is allowed and passed as a null pointer. for the nonnull - variant, passing a # f value will raise an exception. [ type ] ( ref type ) a c + + reference type. reference types are handled the same way as pointers inside scheme code. [ type ] ( function resulttype ( argumenttype1... [... ] ) [ callconv ] ) a function pointer. callconv specifies an optional calling convention and should be a string. the meaning of this string is entirely platform dependent. the value # f is also allowed and is passed as a null pointer. scheme objects [ type ] scheme - object an arbitrary, raw scheme data object ( immediate or non - immediate ). a scheme - object is passed or returned as a c _ word, the internal chicken type for objects. typically, this consists of an object header and tag bits. it is up to you to build or take apart such objects using the core library routines in chicken. h and runtime. c. more information on object structure can be found in data representation. [ type ] scheme - pointer an untyped pointer to the contents of a non - immediate


take apart such objects using the core library routines in chicken. h and runtime. c. more information on object structure can be found in data representation. [ type ] scheme - pointer an untyped pointer to the contents of a non - immediate scheme object ; for example, the raw byte contents of a string. only allowed as an argument type, not a return type. the value # f is also allowed and is passed as a null pointer. for the nonnull - variant, passing # f will raise an exception. don ' t confuse this type with ( c - pointer... ) which means something different ( a machine - pointer object ). scheme - pointer is typically used to get a pointer to the raw byte content of strings and blobs. but if you pass in a srfi - 4 vector, you will get a pointer to a blob object header ( not the blob ' s contents ), which is almost certainly wrong. instead, convert to a blob beforehand, or use a srfi - 4 specific type. user - defined c types [ type ] ( struct name ) a struct of the name name, which should be a string. structs cannot be directly passed as arguments to foreign functions, nor can they be result values. however, pointers to structs are allowed. [ type ] ( union name ) a union of the name name, which should be a string. unions cannot be directly passed as arguments to foreign functions, nor can they be result values. however, pointers to unions are allowed. [ type ] ( enum name ) an enumeration type. handled internally as an integer. c + + types [ type ] ( instance cname schemeclass ) a pointer to a c + + class instance wrapped into a scheme object instance. cname should designate the name of the c + + class, and schemeclass should be the class that wraps the instance pointer. ( make schemeclass ' this pointer ) ( slot - ref instance ' this ) [ type ] ( instance - ref cname schemeclass ) a reference to a c + + class instance. [ type ] ( template type argtype... ) a c + + template type. for example vector < int > would be specified as ( template " vector " int ). template types cannot be directly passed as arguments or returned as results. however, pointers to template types are allowed. type qualifiers [ type ] ( const type ) the foreign type


int > would be specified as ( template " vector " int ). template types cannot be directly passed as arguments or returned as results. however, pointers to template types are allowed. type qualifiers [ type ] ( const type ) the foreign type type with an additional const qualifier. map of foreign types to c types | foreign type | | c type | | [ nonnull - ] blob | | unsigned char * | | [ nonnull - ] u8vector | | unsigned char * | | [ nonnull - ] u16vector | | unsigned short * | | [ nonnull - ] unsigned - c - string | | unsigned char * | | ( [ nonnull - ] c - pointer type ) | | type * | | ( enum name ) | | enum name | | ( struct name ) | | struct name | | ( ref type ) | | type & | | ( template t1 t2... ) | | t1 < t2,... > | | ( union name ) | | union name | | ( function rtype ( atype... ) [ callconv ] ) | | [ callconv ] rtype ( * ) ( atype,... ) | | ( instance cname sname ) | | cname * | | ( instance - ref cname sname ) | | cname & | previous : accessing external objects