Showing papers by "Clemson University published in 1968"
TL;DR: The model should be of value in investigations of the stability of biological processes used for the treatment of certain industrial wastes such as those containing phenols, thiocyanates, nitrates, ammonia, volatile acids, etc., which are known to be inhibitory to many of the organisms metabolizing them.
Abstract: A mathematical model is presented for both batch and continuous cultures of microorganisms utilizing inhibitory substrates. The key feature of the model is the use of a inhibition function to relate substrate concentration and specific growth rate. Simulation studies show that the primary result of inhibition by substrate in a batch culture is an increase in the lag time whereas in continuous culture inhibition by substrate may result in process instability. The model should be of value in investigations of the stability of biological processes used for the treatment of certain industrial wastes such as those containing phenols, thiocyanates, nitrates, ammonia, volatile acids, etc., which are known to be inhibitory to many of the organisms metabolizing them.
1,157 citations
TL;DR: With the exception of a few medico-legal papers that discuss arthropods of tombs and graves, little or nothing is known concerning the processes of decomposition of animal bodies beneath the soil.
Abstract: THE decomposition of animals after death is of limited aesthetic appeal but very important. Several recent papers1–5 have described aspects of the ecology of carrion on the soil surface or other exposed locations. With the exception of a few medico-legal papers6–8 that discuss arthropods of tombs and graves, little or nothing is known concerning the processes of decomposition of animal bodies beneath the soil.
176 citations
112 citations
TL;DR: Adaptability of mixed populations is a key to the study of the microbiology of natural environments and understanding of the mechanisms underlying this adaptation must come from investigations of population dynamics and microbial interactions.
Abstract: Publisher Summary Mixed culture phenomena are not merely composites of the pure culture behavior of the organisms present. The performance of a complex microbial process depends on interactions between its species and strains. Microorganisms have vastly different nutritional requirements. They exhibit a wide range of growth rates and thrive at various conditions of pH, temperature, ionic strength, and the like. In spite of this diversity, species persist in nature throughout times of hardship and can flourish when favorable conditions occur. Thus the occurrence of unusual physical or chemical conditions or of rare nutritional circumstances leads to population changes in which different species achieve predominance so that relatively efficient microbial processes can continue. This adaptability of mixed populations is a key to the study of the microbiology of natural environments. Understanding of the mechanisms underlying this adaptation must come from investigations of population dynamics and microbial interactions.
98 citations
TL;DR: A factor analysis supported the description of the Type-A person as aggressive, impatient, hurried, competitive, and driven by a sense of time urgency, which supported the Rosenman-Friedman rationale.
64 citations
TL;DR: In this article, the deviations from Hooke's law of single-crystal "whiskers" of copper, silver, and iron and fibers of fused quartz have been measured, which are related to the third-order elastic constants.
Abstract: The deviations from Hooke's law of single-crystal "whiskers" of copper, silver, and iron and fibers of fused quartz have been measured. These deviations are related to the third-order elastic constants. The results are in agreement with third-order elastic constants measured by ultrasonic techniques for copper, silver, and fused quartz. Using the pressure derivatives of the second-order elastic constants of iron as measured by Rotter and Smith and the present results, three of the third-order elastic constants of iron have been determined. The values are (in units of ${10}^{12}$ dyn/${\mathrm{cm}}^{2}$) ${{c}_{111}}^{T}=\ensuremath{-}28$, ${{c}_{112}}^{T}=\ensuremath{-}8.0$, and ${{c}_{123}}^{T}=\ensuremath{-}6.1$. For fused quartz, it is possible to make an estimate of a combination of the fourth-order elastic constants: ${{c}_{1111}}^{T}\ensuremath{-}1.4{{c}_{1112}}^{T}+0.34{{c}_{1122}}^{T}+0.23{{c}_{1123}}^{T}=5.5\ifmmode\pm\else\textpm\fi{}1.5\ifmmode\times\else\texttimes\fi{}{10}^{14}$ dyn/${\mathrm{cm}}^{2}$.
49 citations
TL;DR: Changes in the rate of passage of nutrients through the digestive tract may affect the amount of nutrients absorbed by altering the period of time during which digestion and absorption take place, and these effects could provide a partial explanation of the effects of various coccidial infections upon nutrient absorption.
31 citations
TL;DR: In Trial 1, pelleted alfalfa-fed animals declined significantly and grind and pelleting of forage and frequency of feeding upon milk production and milk fat test.
30 citations
TL;DR: In connection with more general studies on the fauna of carrion, 12 species of Hemiptera, representing 6 different families, were collected and 3 were observed to be feeding on carrions, and at least 3 were predatory on dipterous larvae.
Abstract: In connection with more general studies on the fauna of carrion, 12 species of Hemiptera, representing 6 different families, were collected. Of these 12 species, 3 were observed to be feeding on carrion, and at least 3 were predatory on dipterous larvae.
28 citations
TL;DR: Two triphenyltin compounds produced significant changes in the ovarian tissue, including a decreased number of mature follicles, an increased incidence of atresia in early follicle growth, and a pronounced decrease in the number of corpora lutea present.
Abstract: Three insect chemosterilants, hydroxyurea, triphenyltin acetate, and triphenyltin chloride, were tested to determine their effect on ovarian tissue in the albino rat. The compounds were administered orally at dosage rates of 40 mg per kg per day for hydroxyurea, and 20 mg per kg per day for the 2 organotin compounds for periods of 4, 9, 14, 19, and 24 days. Animals were killed on the day following cessation of treatment and histological preparations of ovaries were made and evaluated.
Hydroxyurea had no significant effect on the ovarian tissue and no side effects were detected. However, both triphenyltin compounds produced significant changes in the ovarian tissue. Among these changes were a decreased number of mature follicles, an increased incidence of atresia in early follicle growth, and a pronounced decrease in the number of corpora lutea present. This last effect was regarded as a decrease in ovulation, and thus, a decreased fertility. This effect, as well as the others listed above, was present on or by the 1st 5-day sample period.
24 citations
TL;DR: The incidence and the persistence of diarrhea were somewhat greater in calves fed from open pails than in those fed from nipple feeders, but weight gains were similar.
TL;DR: Treatment with the 2 tin compounds produced several degenerative changes in testicular tissue, including a decreases in the number of cell layers per seminiferous tubule, a decrease in tubule diameter and overall testicular size, a depletion of the more advanced cell forms from the tubules, and a closing of tubule lumina.
Abstract: Research was initiated in 1966 to determine the histological effects of 3 insect chemosterilants on testicular tissue in male albino rats. The 3 compounds, hydroxyurea, triphenyltin acetate, and triphenyltin chloride, were administered orally to 20 rats each, at dosage rates of 40, 20, and 20 mg per kg per day, respectively, over a period of 19 days. Animals were killed on the 20th day, and histological preparations of the testes were made.
Hydroxyurea produced no noticeable effects on testicular structure or on the general physiology of animals to which it was administered. However, treatment with the 2 tin compounds produced several degenerative changes in testicular tissue, including a decrease in the number of cell layers per seminiferous tubule, a decrease in tubule diameter and overall testicular size, a depletion of the more advanced cell forms from the tubules, and a closing of tubule lumina. Effects were more pronounced in rats treats with triphenyltin acetate.
TL;DR: In this paper, a study and comparison of these theories is carried out illustrating the agreement and controversy between them, and the factors that affect the position of the fiber in the yarn are outlined and discussed with regard to fiber, yarn, and processing factors.
Abstract: The study of yarn structure and positioning of the constituent fibers to form a continuous strand has attracted the attention of many workers who have used an idealized helical structure as a basis for these studies. The existence of this structure has been criticized as being unuseful and not manufacturable. Studies of the actual arrangement of fibers in the yarn have been carried out and different theories explaining the behavior of fibers in the process of yarn formation have been given. In this paper, a study and comparison of these theories is carried out illustrating the agreement and controversy between them. The factors that affect the position of the fiber in the yarn are outlined and discussed with regard to fiber, yarn, and processing factors to assist those dealing with blended yarns. Suggestions are advanced for further, more funda mental studies.
TL;DR: This research found the feasibility of the idea that with improved methods of technology living attenuated vaccines may become the main method of prophylaxis in the future in the control of fowl cholera in turkeys.
TL;DR: The degree of parasitism of R. frustrana in the top whorl of the pine trees as compared with the lower level was significant at the 1% level, and there was no significant difference in parasitism as a result of orientation, number ofR.
Abstract: Responses of Rhyacionia frustrana (Comstock) parasites to height level, orientation, and population density the host were studied in the Piedmont Region of South Carolina. The variation in degree of parasitism and the influencing factors in this study were attributed to variation among plantations and between the height levels of the pine trees. The degree of parasitism of R. frustrana in the top whorl of the pine trees as compared with the lower level was significant at the 1% level. There was no significant difference in parasitism as a result of orientation, number of R. frustrana per pine tip, or the interactions produced by these factors.
TL;DR: Pregastric esterase normally secreted by calves consuming whole milk seems to have the capacity to hydrolyze milk lipids in excess of quantities normally in the diet.
TL;DR: In this article, the authors used thermogravimetric analysis to study the kinetics of decomposition of MgSO 4 between 920°C and 1080°C as a function of sample mass and processing pressure.
TL;DR: A review of the literature reveals a lack of information concerning family differences within a breed.
TL;DR: The results of 117 milk sample comparisons indicated that microscopic Procedures 1, 2, and 3 showed a good correlation with the Wisconsin test, but Procedure 1 was best for predicting Wisconsin test values.
TL;DR: A dilute HCl wash of Ag3Sn powder results in a dental amalgam exhibiting 20% higher tensile strength and it was found that the fracture propagation paths in treated and untreated specimens were different.
Abstract: A dilute HCl wash of Ag3Sn powder results in a dental amalgam exhibiting 20% higher tensile strength. It was found that the fracture propagation paths in treated and untreated specimens were different.
The support of the National Institute of Dental Research under Grant No. DE-30233 and Program Project DE-02111 is gratefully acknowledged.
TL;DR: Initiation of lipolysis through sham feeding and amplification by nipple consumption indicate that the activity of the lipolytic enzymes is related closely to the exposure of the milks in the oral and esophageal areas of the calf.
TL;DR: In this article, a mechanism for the formation of the basic salt and its subsequent bonding to the magnesium oxide grain surfaces is suggested, where aqueous solutions of nickelous nitrate are added to magnesium oxide powder, and a basic salt with the idealized formula of Ni2(OH)3NO3 forms and bonds the aggregate together.
Abstract: THE low temperature cementation effects in the nickelous nitrate–water–magnesium oxide system have only recently been reported1. When aqueous solutions of nickelous nitrate are added to magnesium oxide powder, a basic salt with the idealized formula of Ni2(OH)3NO3 forms and bonds the magnesium oxide aggregate together. A mechanism for the formation of the basic salt and its subsequent bonding to the magnesium oxide grain surfaces is suggested.
TL;DR: Studies with linoleic acid in laying diets for chickens have been of interest to a number of researchers and one expressed doubt that a practical diet incorporating small grains, .
TL;DR: The objective of this research was to determine the distribution of leafhopper vectors of phony peach disease in South Carolina, and the major vector, Homalodisca coagulata, was found to be distributed mainly in the Coastal Plain area, peach trees.
Abstract: The objective of this research was to determine the distribution of leafhopper vectors of phony peach disease in South Carolina. Eleven collection sites were chosen from. Coastal Plain and Piedmont areas to account perhaps for the pattern of disease range.
Leafhoppers were trapped in 1965-66 by using Tangle-foot®-covered traps hung in peach trees, and sweeping of Vegetation under the trees.
The major vector, Homalodisca coagulata , (Say), was found to be distributed mainly in the Coastal Plain area, peach trees. Oncometopia orbona (F.) and Graphocephala versuta (Say) were collected from all sites. Cuerna costalis (F.) was taken from several spots, but nowhere was it abundant. The distribution of H. insolita (Walker) was nearly the same as that of H. coagulata even though it was collected in fewer numbers.
Although G. versuta, C. costalis , and H. insolita , are classified mainly as grass feeders, their having beencollected from several traps indicates their association with peach trees.
TL;DR: Tepa and triphenyl tin chloride offered free choice with non treated diet to a large cage population of reproducing flies completely inhibited reproduction and the population was completely eliminated in 35 days.
Abstract: Inhibition of reproduction in Musca domestica L. with triphenyl tin acetate and triphenyl tin chloride alone and in combination with other chemosterilants is reported. Both test compounds produced excessive mortality when offered in the diet at rates above 0.25 mg per gram diet. Male flies were less affected than females at tolerable dosage rates. Longevity of females treated for 24 hours was normal, life of males was shortened slightly. When offered in the diet to ovipositing females both test compounds reduced the number of eggs produced and percent hatch. Only a few viable eggs were deposited after the 1st day of treatment. Both compounds compared favorably with tepa in reducing hatch when offered to mated sexually mature females. Combinations of either compound with apholate or tepa when offered in the diet to day-old males did not reduce male competitiveness for virgin females. Tepa and triphenyl tin chloride offered free choice with non treated diet to a large cage population of reproducing flies completely inhibited reproduction. The population was completely eliminated in 35 days.
TL;DR: In this paper, high purity polycrystalline magnesium samples near 4.2°K have been irradiated with 0.4 and 0.3 MeV electrons, and subsequent isochronal recovery was observed to occur in two stages: one centered near 6.8°K and the other centered near 11.4°K
TL;DR: In this paper, the Predictive Value of Neutral Positions in Opinion and Attitude Research (PVAR) is presented. But it does not consider neutral positions in opinion and attitude research.
Abstract: (1968). The Predictive Value of Neutral Positions in Opinion and Attitude Research. The Journal of Psychology: Vol. 69, No. 2, pp. 145-154.