Showing papers by "University of Georgia published in 1970"
TL;DR: Eimeria maxima and E. brunetti were found to be the most difficult species to score since the gross pathologic picture has been difficult to correlate with weight gains or other indications of pathogenicity.
1,199 citations
TL;DR: Calculated productivity of various calcareous algal zones indicates that these do not contribute significantly to overall reef production on atolls of the northern Marshall Islands, and island reefs are less productive than previously studied inter—island reefs.
Abstract: Primary productivity of reef—building algae was studied by putting samples from the reef in a closed system and measuring oxygen exchange in the light and in the dark Gross productivity determined for 32 samples in full sunlight had a mean value of 0048 mg O2 cm—2 hr—1 Photosynthesis was found to increase with the logarithm of light intensity up to 1,000 ft—c and was constant between 1,000 and 8,000 ft—c Rates of gas exchange in flowing water showed no correlation with water velocity but were greater than rates in still water Daily patterns of photosynthesis were calculated for populations of calcareous algae living on the submarine faces of the windward sides of atolls During most of the daylight hours light is probably not a limiting factor for photosynthesis in these populations Calculated productivity of various calcareous algal zones indicates that these do not contribute significantly to overall reef production on atolls of the northern Marshall Islands Island reefs are less productive than previously studied inter—island reefs
503 citations
TL;DR: Fine jets of water can be used to remove coral tissue quantitatively from skeleton in a form suitable for a variety of chemical analyses, including that of total organic carbon.
Abstract: Fine jets of water can be used to remove coral tissue quantitatively from skeleton in a form suitable for a variety of chemical analyses, including that of total organic carbon.
269 citations
TL;DR: The most widely used method for estimating the reliability of ratings or judgments is with the intraclass correlation, or some variation of it (Ebel, 1951) as mentioned in this paper, which is basically concerned about the consistency with which a group of judges place a given item (or items) into categories.
Abstract: IN carrying out research, one is often confronted with the need to estimate the reliability with which a group of judges place stimuli into categories. Guttman (1946) presents methods for estimating the upper bound and lower bound reliabilities of such data. Essentially, these estimates are functions of the number of categories available and the proportion of instances with which the modal response is chosen. In his discussion of reliability, Guilford (1954) acknowledges the interest in reliability of categorical data and concludes that there has not been sufficient experience with approaches such as that proposed by Guttman to permit an evaluation. Probably the most generally applicable and widely used method for estimating the reliability of ratings or judgments is with the intraclass correlation, or some variation of it (Ebel, 1951). Regarding the matter of categorical data, one is basically concerned about the consistency with which a group of judges place a given item (or items) into categories. As a measure of this kind of consistency, the intraclass correlation suffers from the limitation of requiring non-zero variance between items being rated in order to obtain a significant coefficient. It obviously follows that the
199 citations
TL;DR: A new species—Clostridium formicoaceticum—is described, which ferments fructose and several hexonic and hexuronic acids to acetate and formate and differs from C. aceticum in its inability to grow on hydrogen plus carbon dioxide.
Abstract: A new species—Clostridium formicoaceticum—is described. It ferments fructose and several hexonic and hexuronic acids to acetate and formate. During active growth acetate is the main product of the fermentation. Considerable quantities of formate appear among the fermentation products in the stationary growth phase.
139 citations
TL;DR: In studies involving special and purified diets, approximately 9 ppm of zinc were adequate for normal health and performance of calves, however, in a few instances, 20 to 40 ppM zinc in practical diets were not sufficient for optimum performance, but in others, such levels were adequate.
134 citations
TL;DR: It is suggested that relatively small amounts of zooplankton may be important as a source of phosphorus and perhaps of other essential nutrients for both the coral and its algal symbionts.
Abstract: Over 15 days of continuous monitoring, the mean nocturnal concentration of drifting net zooplankton in a coral reef community on the Bermuda platform was 0.83 mg m−3. The mean respiration rate of reef-building corals at the study site was calculated to be 6.4 g O2 day−1 m−2 of reef bottom. Using these data we show that the energy requirement of these corals was more than an order of magnitude greater than the energy they could obtain by capturing the sparse zooplankton in the surrounding waters.
The question follows, why, if corals can exist in the absence of energetically significant quantities of zooplankton, do their elaborate anatomic modifications for catching zooplankton persist? Evidence indicates that corals cannot obtain their phosphorus requirements from solution. We therefore suggest that relatively small amounts of zooplankton may be important as a source of phosphorus and perhaps of other essential nutrients for both the coral and its algal symbionts.
134 citations
110 citations
TL;DR: The results indicated that septal ablation increased the aggressiveness of both socially naive and experienced dominant hamsters, with high levels of aggression between paired animals.
92 citations
TL;DR: An alkaloid, trans-2-methyl-6-n-undecylpiperidine (solenopsin A), has been isolated from the venom of the fire ant Solenopsis saevissima and the structure has been confirmed by an unambiguous synthesis.
Abstract: An alkaloid, trans-2-methyl-6-n-undecylpiperidine (solenopsin A), has been isolated from the venom of the fire ant Solenopsis saevissima. The structure has been confirmed by an unambiguous synthesis.
87 citations
TL;DR: Changes in the amount and kind of social behavior were observed in male hamsters following amygdalectomy and both preoperatively dominant and submissive animals retained their social status after surgery.
TL;DR: Citral is identified as the probable key factor responsible for the successful robbing activities of L. limao workers and the role of exocrine products which are employed as allomones by robbing bees and ants is discussed.
TL;DR: The results indicate that the plant hormone abscisic acid may control translation inhibition by a mechanism involving RNA synthesis.
TL;DR: A method for representing individual growth rates of aquatic insects from field sampling is presented using the mean instar number as the age criterion, and an example is presented which shows the possible role of temporal separation in niche differentiation between two similar species.
Abstract: A method for representing individual growth rates of aquatic insects from field sampling is presented using the mean instar number as the age criterion. Various examples are used to show how the method is useful in making both intra— and interspecific comparisons. Significantly different growth rates are shown between populations of the same species in different habitats. Also, an example is presented which shows the possible role of temporal separation in niche differentiation between two similar species. See full-text article at JSTOR
TL;DR: It is concluded that synthetic trypsin inhibitors successfully prevent fertilization in vivo and reduce the fertility of ejaculated sperm.
TL;DR: In this article, surface tension responses for solutions of salt-soluble protein from cow meat, beef hearts, beef cheek meat, pork trim and pork cheek meat were found to follow the Type III curves assigned to surface active agents.
Abstract: SUMMARY– Surface tension responses for solutions of salt-soluble protein from cow meat, beef hearts, beef cheek meat, pork trim and pork cheek meat were found to follow the Type III curves assigned to surface-active agents. The stability of emulsions prepared utilizing salt-soluble protein of the meats was significantly affected by concentration of protein and level of oil. As either concentration of protein or of oil was increased, higher and more significant stability of the emulsions was observed. Emulsions prepared from protein of each type of meat had similar responses for stability. High and significant correlation was found between protein surface activity and emulsion stability. Little change in emulsion viscosity was found except at the upper protein and oil levels tested.
TL;DR: The results show that energy from photosynthetic phosphorylation can be used to maintain cytoplasmic polyribosomes (and thus to drive cytop lasmic protein synthesis), at least under anaerobic conditions.
Abstract: Nitrate reductase activity was induced by nitrate in green corn (Zea mays) leaves in either light or darkness. The induction process required oxygen in darkness but not in light. A light treatment was required before the enzyme could be induced in etiolated leaves.The capacity for nitrate reductase induction by nitrate was positively correlated with the level of cytoplasmic polyribosomes under a variety of experimental conditions. (a) Light-grown leaves contained high levels of polyribosomes (84% of the total population, most of which were of the 80 S type); similarly high levels of nitrate reductase activity were induced. (b) The level of polyribosomes and the ability to form nitrate reductase activity rapidly decreased in light-grown leaves following transfer to an anaerobic environment in the dark; both parameters were maintained at a high level when light-grown leaves were kept in the light under anaerobic conditions. (c) The ability of light-grown leaves, previously placed in darkness under nitrogen to dissociate polyribosomes to monoribosomes, to form nitrate reductase activity again correlated with the level of reformed polyribosomes following transfer of the leaves back to light. (d) Etiolated leaves contained a low level of cytoplasmic polyribosomes (27%), and nitrate reductase activity was induced following exposure to light only after a lag of 2 to 4 hours. During this lag period there was a marked increase in the level of polyribosomes.The ability of leaves to form nitrate reductase activity and the level of polyribosomes also correlated with the level of in vitro incorporation of amino acids into protein by the isolated ribosome preparations. Thus, the apparent requirement of light for nitrate reductase induction in etiolated leaves seems not to be specific. Rather an influence of light upon the development of an active protein-synthesizing apparatus as evidenced by the state of polyribosomes is indicated.The results also show that energy from photosynthetic phosphorylation can be used to maintain cytoplasmic polyribosomes (and thus to drive cytoplasmic protein synthesis), at least under anaerobic conditions.
TL;DR: Feeding studies revealed that P. maria had definite preferences for specific kinds of leaves; Elm, alder, sourwood, and dogwood were the most preferred; rhododendron, white pine, white oak, and chestnut oak were the least preferred.
Abstract: Nymphs of Peltoperla maria Needham & Smith were exposed to 15 species of autumn-shed leaves in the laboratory. The insects fed on the cuticle and mesophyll of the leaves, leaving most of the vascular system intact. This feeding resulted in a characteristic skeletonized pattern to the leaves. The insects consumed leaves inamounts (by dry weight) in excess of their dry body weight in a 2-week period. Feeding studies revealed that P. maria had definite preferences for specific kinds of leaves. Elm, alder, sourwood, and dogwood were the most preferred; rhododendron, white pine, white oak, and chestnut oak were the least preferred. There was evidently increased leaching of tannic acid from leaves on which the insects were feeding. The higher tannic acid content of the water from feeding containers was apparentlya result of increased leaching from the finely ground leaf material in the fecal pellets.
TL;DR: Contrary to Piagetian expectations, the illusion magnitudes resulting from the colored figures did not decline with age.
Abstract: Mueller-Lyer figures produced by lightness contrast (white on black) and by hue contrast in the absence of lightness contrast (red, yellow, green, or blue on gray) were presented to subjects aged nine to adult Contrary to Piagetian expectations, the illusion magnitudes resulting from the colored figures did not decline with age
TL;DR: Air-dried smears of saline suspensions of mammalian spermatozoa were stained for 10-60 min at room temperature in a mixture of eosin Y, fast green FCF, and naphthol yellow S; in all species examined except the rat, acrosomes were stained greenish blue to bluish green or blue depending on their thickness; in the rats, they displayed more affinity for eOSin and were reddish.
Abstract: Air-dried smears of saline suspensions of mammalian spermatozoa were stained for 10-60 min at room temperature in a mixture of eosin Y, fast green FCF, and naphthol yellow S (0.1% w/v, each dye) in 1.0% aqueous acetic acid. They were then blotted, rinsed in 1.0% acetic acid until no more dye was removed (0.5-1.5 min), blotted and allowed to dry completely, rinsed in xylene and mounted in synthetic resin. In all species examined except the rat, acrosomes were stained greenish blue to bluish green or blue depending on their thickness; in the rat, they displayed more affinity for eosin and were reddish. In all species, spermatozoan nuclei were strongly stained by naphthol yellow. In intact sperm heads, postnuclear cap had a yellowish green appearance. Midpieces of rodent spermatozoa, especially those of younger gametes, were stained bright red while those of ejaculated bull and rabbit spermatozoa were stained blue-green. Cytoplasmic droplets associated with rodent spermatozoa were consistently stained a dark...
TL;DR: In this article, the infrared and proton NMR spectra of the new compounds are discussed and compared with those of the corresponding h 5 -indenyl derivatives. But they are not shown to be monosubstituted, unlike C 13 H 9 Mn(CO) 2 P(C 6 H 5 ) 3 and C 9 H 7 Mn( CO) 2 E(CoHs)3 (E = P, As, or Sb), respectively.
TL;DR: The hypothesis is proposed that this synchrony results from the sharing by nucleus and kinetoplast of the same mechanism for the production of the deoxyribonucleotides used in replication of their respective DNAs.
Abstract: SYNOPSIS. Autoradiographic technics with tritium-labeled thymidine have been used to determine G1, S, G2 and D for the kinetoplast and the nucleus of Crithidia fasciculata at 15, 25 and 32 C. The kinetoplast completes division before the nucleus at all 3 temperatures. The S phases of both organelles occur in approximate synchrony and are approximately equal in length but the nucleus begins and completes S before the kinetoplast at the 2 lower temperatures. This relationship is reversed at 32 C. Most of the effect of temperature on generation time is due to its effect on the length of S.
The results are compared with similar studies on C. luciliae, Trypanosoma mega, other protozoa and tissue cells in culture. The role of the approximate synchrony of nuclear and kinetoplastic cycles in maintenance of the kinetoplastic condition is discussed and the hypothesis is proposed that this synchrony results from the sharing by nucleus and kinetoplast of the same mechanism for the production of the deoxyribonucleotides used in replication of their respective DNAs.
TL;DR: None of 10 ova recovered from unmated hens showed signs of development after culture under the same conditions but without incubation with spermatozoa, providing direct evidence that avian spermatoza do not require a period of capacitation within the hen's reproductive tract in order to fertilize ova.
Abstract: The in vitro culture system developed was capable of supporting recently ovulated chicken ova in a viable state for at least 24 hr. Utilizing this system, 8 out of 10 ova obtained from the body cavity or infundibulum of unmated White Leghorn hens, were successfully fertilized in vitro. Microscopic examination of the eight fertile blastodiscs revealed that five had proceeded to the blastula state of development during the 24-hr culture period. The remaining three fertile ova, apparently retarded, had not progressed beyond the early cleavage stage of development. None of 10 ova recovered from unmated hens showed signs of development after culture under the same conditions but without incubation with spermatozoa. These observations afford direct evidence that avian spermatozoa do not require a period of capacitation within the hen’s reproductive tract in order to fertilize ova.
TL;DR: The endoplasmic reticulum of Saprolegnia, Dictyuchus, Synura and Cryptomonas may contain tubules less than 20 nm in diameter that are morphologically similar to Flimmer hairs, which are attached to the flagellum sheath by a tapering end-piece.
Abstract: The endoplasmic reticulum of Saprolegnia, Dictyuchus, Synura and Cryptomonas may contain tubules less than 20 nm in diameter. In Saprolegnia these tubules have a maximum length of 1.6 µm, a wall of a single layer of colchicine-resistant, osmiophilic subunits, and a tapering end-piece. Flimmer hairs (flagellar hairs) are morphologically similar and are attached to the flagellum sheath by a tapering end-piece. It is suggested that Flimmer hairs are produced in cisternae of the endoplasmic reticulum of the above organisms. Cryptomonas bears 2 rows of Flimmer hairs on one flagellum and a single row of shorter ones on the other.
TL;DR: Pseudomonas aeruginosa, when grown on d -glucose, was shown to possess both a specific glucose transport system and a high level of glucokinase (EC 2.7.1.2), and a transport system for fructose was formed as discussed by the authors.
TL;DR: Results indicate that dyadic interaction facilitated originality of thinking but the differences are stronger for the college students than for the 5-yr.-olds.
Abstract: Two experiments, one with college students and the other with 5-yr.-old children as Ss, were conducted to test the hypothesis that dyadic interaction will facilitate the production of original ideas among individuals. 20 college Ss were administered 4 tasks from the Torrance Tests of Creative Thinking under standard conditions; 20 others randomly assigned to dyads from the same population were tested under the same conditions except that they were encouraged to hitchhike on one another's ideas but forbidden to repeat an idea produced by the other. Similarly, 24 5-yr.-olds were tested alone and 22 of their randomly selected classmates were tested in dyads. Results indicate that dyadic interaction facilitated originality of thinking but the differences are stronger for the college students than for the 5-yr.-olds.
TL;DR: In this article, the authors present a test that can be used in classifying adolescents and adults for experimental groupings to facilitate their search for better ways of teaching creative or creatively-oriented people.
Abstract: (the results of research) to a large class of 200 or more students. The plan was to have students respond to the instrument, explain the procedure used in developing it, have students score their own responses, and explain the underlying rationale and research basis for each item. Second, he was interested in developing for research purposes a brief, easily administered and scored test that could be used in classifying adolescents and adults for experimental groupings to facilitate his search for better ways of teaching creat i ve I y-gifted or creatively-oriented people.
TL;DR: It is suggested that phosphorylation coupled to electron transfer with the reduction of fumarate may be of general occurrence in anaerobic and facultativeAnaerobic bacteria.
TL;DR: The results establish that mesophyll cells fix CO2 by a β-carboxylation while the bundle sheath cells fixCO2 by car boxylation of ribulose-1,5-diphosphate.