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Author (up) Carl B. Koford file  url
openurl 
  Title Prairie Dogs, Whitefaces, and Blue Grama Type Journal Article
  Year 1958 Publication Abbreviated Journal  
  Volume Issue Pages 3-78  
  Keywords Prairie dog, Rodents, Grasses, Vegetation, Prairie soils, Plants, Forbs, Burrows, Forage  
  Abstract Man changes his environment to suit his

needs. If he wants protection from cold or

enemies, he builds houses and dwells in towns.

If he needs food, he destroys weeds and fos-

ters crops. But this ability to alter surround-

ings to his own advantage is not unique with

man; it is shared by many humble animals.

Among these are the large rodents of the

western grasslands, the ground squirrels and

the prairie dogs.
 
  Call Number Serial 1863  
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Author (up) Dyksterhuis, E.J. file  url
openurl 
  Title Ecological principles in range evaluation Type Journal Article
  Year 1958 Publication The Botanical Review Abbreviated Journal Bot. Rev  
  Volume 24 Issue 4 Pages 253-272  
  Keywords Vegetation, Synecology, Rangeland soils, Forest soils, Soil ecology, Rangelands, Ecosystems, Pastures, Plants, Climax communities  
  Abstract Range ecology has certain unique features, but its fundamentals

are those of all ecology. Thus, current perspective in range evalua-

tion was expressed more than 30 years ago by the marine ecologist

who postulated: If the problem covers enormous numbers of or-

ganisms, or a large extent of space, or a long period of time, the

effect of minor factors is so deeply submerged that we are not able

to trace them. The greater the magnitude of the problem the fewer

the factors which need to be considered in its analysis, and the

less complex the terms of its solution (Allen, '26).

For our purpose the term “range evaluation” will be used to

mean accurately estimating the amount, quality or worth of range.

Range will mean only native pasture on natural grazing land.

Ranges generally are extensive areas producing little per acre in

comparison with tame pastures. Moreover, ranges have far greater
 
  Call Number Serial 1860  
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Author (up) Favelukes, G.; Stoppani, A.O. url  openurl
  Title Baker's-yeast fumarase, a thiol enzyme Type Journal Article
  Year 1958 Publication Biochimica et Biophysica Acta Abbreviated Journal Biochim Biophys Acta  
  Volume 28 Issue 3 Pages 654-655  
  Keywords *Hydro-Lyases; Saccharomyces cerevisiae/*metabolism; *Hydrases; *SACCHAROMYCES CEREVISIAE/metabolism  
  Abstract  
  Call Number Grinnell @ engelk @ Serial 483  
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Author (up) Schmidt-Nielsen, K.; Jorgensen, C.B.; Osaki, H. file  url
openurl 
  Title Extrarenal salt excretion in birds Type Journal Article
  Year 1958 Publication The American Journal of Physiology Abbreviated Journal Am J Physiol  
  Volume 193 Issue 1 Pages 101-107  
  Keywords *Birds; Sodium Chloride/*metabolism; *Birds; *SODIUM CHLORIDE/metabolism  
  Abstract Investigations on cormorants (Phalacrocorax auritus) gave no evidence to support the hypothesis that sea birds must drink sea water in order to cover their normal needs for water. When the birds were fed fresh fish the water content of the fish was more than adequate for the renal elimination of salts and nitrogen (uric acid). However, it was found that when given a salt load cormorants also employ an extrarenal mechanism for electrolyte elimination. Whether the load is imposed orally or by infusion of hypertonic NaCl solution, cormorants excrete a highly hypertonic liquid that drips out from the internal nares and collects at the tip of the beak, from which the birds shake the drops with a sudden jerk of the head. The concentration (500600 mN NaCl) and the rate of secretion (up to 0.2 ml/min. in a 1.5-kg bird) are so high that with continuous secretion the entire NaCl content of the body could be eliminated in roughly 10 hours. The secretion contains practically only sodium and chloride in nearly equivalent amounts. The production of the nasal secretion is stimulated also by a nonelectrolytic osmotic load (sucrose), which indicates that the mechanism responds to general osmotic conditions rather than specifically to the sodium or chloride concentration of the plasma. The nasal secretion has been observed only after an osmotic load and never in fasting birds or after ingestion of fish or fresh water.  
  Call Number Serial 191  
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