Showing papers by "Mississippi State University published in 1991"

An adaptive and fault tolerant wormhole routing strategy for k-ary n-cubes

Abstract: The concept of virtual channels is extended to multiple virtual communication systems that provide adaptability and fault tolerance in addition to being deadlock-free. A channel dependency graph is taken as the definition of what connections are possible, and any routing function must use only those connections defined by it. Virtual interconnection networks allowing adaptive, deadlock-free routing are examined for three k-ary n-cube topologies: unidirectional, torus-connected bidirectional, and mesh-connected bidirectional. >

The relationship between marketing orientation and entrepreneurial orientation

Abstract: Increasing environmental uncertainty has focused greater attention on firms’ overall business orientations, particularly on the marketing orientation and the entrepreneurial orientation. The major ...

Ehrlichial diseases of dogs.

Abstract: Ehrlichial diseases of dogs currently are recognized to be caused by Ehrlichia canis, Ehrlichia platys, Ehrlichia equi, and Ehrlichia risticii. Information on each disease’s history, transmission, pathogenesis, clinicopathologic findings, diagnosis, therapy, and prevention is presented in this article. Ehrlichia canis is the most common cause of clinical illness. Case reports are included to illustrate common presentations of Ehrlichia canis infections.

Handbook of Nutrient Requirements of Finfish

Abstract: Handbook of nutrient requirements of finfish , Handbook of nutrient requirements of finfish , مرکز فناوری اطلاعات و اطلاع رسانی کشاورزی

Influences Upon Consumer Expectations of Services

Abstract: Provides insight into the concept of quality in the service market by investigating possible influences on consumer expectations of quality and how these expectations may be better met. Reports on a study examining the effects of certain stimuli on expectations regarding different types of service. Discovers that significant differences were found regarding the nature of the expectations as the stimuli werevaried, differences which remained after involvement and the removal of personal need effects. Offers recommendations to service providers and includes an explanation of the methodology used in the study.

Temperature Effects on Cotton Canopy Growth, Photosynthesis, and Respiration

Abstract: The ecological range of temperature conditions where cotton (Gossypium hirsutum L.) is commercially grown frequently exceeds the temperature range of available data. To predict growth, development, and responses of the primary physiological processes to those conditions, data at both lower and higher temperatures are needed. Cotton plants were grown in naturally lit, temperature- and CO 2 -controlled chambers. Plants grown at near-optimum temperatures (30 and 35 o C day temperature) fixed twice as much CO 2 at high photosynthetically active radiation during the fruiting period as did plants growing at 20 o C (...)

Improvement of Cottonseed Meal Protein with Supplemental Lysine in Feeds for Channel Catfish

Abstract: Two studies were conducted to evaluate cottonseed meal (CSM) with and without supplemental lysine as a substitute for soybean meal (SBM) in catfish feeds. One study was conducted in aquaria under controlled environmental conditions with fingerling channel catfish, and the other was conducted with fish raised in 6-m3 net pens suspended in a 1.6-ha earthen pond. In each study, solvent extracted CSM was substituted for SBM on a nitrogen basis. Supplemental lysine was added to the feeds in which CSM replaced 50 and 100% of the SBM because they were estimated to be deficient in available lysine. In the aquarium study, 0, 25, 50, and 100% of the SBM was replaced with CSM. The same feeds used in the aquarium study were used in the net pen study, except that the 25% substitution was not used. Fish raised in aquaria were fed 4% body weight divided into two equal daily feedings, and those raised in net pens were fed to station once daily. Data presented herein demonstrate that channel catfish can effectively utiliz...

Discretized Newton-relaxation solution of high resolution flux-difference split schemes

Abstract: A method is presented for the implicit solution of high resolution flux-difference split schemes for which it is impractical to obtain the Jacobian matrix analytically. The method is used frequently in numerical schemes for solving nonlinear systems of equations, but apparently has not been used to date for approximating the Jacobian of the Roe numerical flux vectors. The method consists of obtaining a discretized Jacobian by using simple finite-differences of the flux vectors, and then using this discretized Jacobian in a Newton-relaxation solution method. The method is applied to both compressible and incompressible flows. Numerical results are presented that demonstrate the method works for both inviscid and viscous flows.

Temperature Effect on Growth and Development of Cotton During the Fruiting Period

Abstract: (...) The purpose of this research was to quantify plant responses to temperatures, so that these responses could be incorporated into plant growth models used to manage cotton crops. Plants, initially grown out of doors in pots, were moved into sunlit, temperature-controlled growth chambers 5 d prior to initial bloom. Growth and development were studied in 20/10, 25/15, 30/20, 35/25, and 40/30 °C day/night temperature regimes from initial bloom. Temperature significantly affected phenology, leaf expansion, internode elongation, biomass production and the partitioning of assimilates to different plant parts (...)

Cocaine Politics : Drugs, Armies, and the CIA in Central America

Abstract: When the San Jose Mercury News ran a controversial series of stories in 1996 on the relationship between the CIA, the Contras, and crack, they reignited the issue of the intelligence agency's connections to drug trafficking, initially brought to light during the Vietnam War and then again by the Iran-Contra affair. Broad in scope and extensively documented, Cocaine Politics shows that under the cover of national security and covert operations, the U.S. government has repeatedly collaborated with and protected major international drug traffickers. A new preface discusses developments of the last six years, including the Mercury News stories and the public reaction they provoked. When the San Jose Mercury News ran a controversial series of stories in 1996 on the relationship between the CIA, the Contras, and crack, they reignited the issue of the intelligence agency's connections to drug trafficking, initially brought to light during the Vietnam War and then again by the Iran-Contra affair. Broad in scope and extensively documented, Cocaine Politics shows that under the cover of national security and covert operations, the U.S. government has repeatedly collaborated with and protected major international drug traffickers. A new preface discusses developments of the last six years, including the Mercury News stories and the public reaction they provoked.

Changes in Peripheral Blood Leukocyte Percentages and Function of Neutrophils in Stressed Channel Catfish

Abstract: Channel catfish Ictalurus punctatus were subjected to a simulated handling (including bleeding) and transport stress. Using flow cytometry in conjunction with monoclonal antibodies to channel catfish B and T lymphocytes (minimal cross-reaction with thrombocytes) and neutrophils coupled with routine hematological methods, we demonstrated significant decreases in the percentage of B lymphocytes and increases in T lymphocytes and neutrophils of transported fish, yet there was no change in neutrophil phagocytic function. These data suggest that the length of the stressing event or the duration of exposure of the neutrophils to cortisol could determine if immune responses become suppressed. These data prompted us to expose channel catfish in vivo, and isolated neutrophils in vitro, to cortisol at various concentrations and for various time periods. Exposure of neutrophils to cortisol concentrations of 100 μg/dL for 2 h did not suppress phagocytosis; however, significant decreases in the percent phagoc...

Dietary regulation of intestinal brush-border sugar and amino acid transport in carnivores.

Abstract: The ability of omnivores and herbivores to regulate reversibly their intestinal brush-border nutrient transporters is functionally related to the unpredictably variable composition of their natural diets. To determine whether carnivores are able similarly to regulate the activities of their intestinal nutrient transporters, we fed to three species of vertebrates that are carnivorous as adults (cats, mink, and leopard frogs) diets with either at least 50% digestible carbohydrate or with negligible carbohydrate levels. Rates of transport for the sugars glucose and fructose and the amino acids (AAs) aspartate, leucine, lysine, and proline were measured throughout the intestine (only proline and glucose in the frogs) by an in vitro everted-sleeve method. Although all three species consume much carbohydrate during early development, only the mink was able to regulate sugar transporter activity in response to changes in levels of dietary carbohydrate. In contrast, the sugar transporters of the cat were unresponsive to varying carbohydrate levels, and long-term feeding of a high-carbohydrate diet caused down-regulation of sugar transport in frogs. Of the three species, only the mink is a member of a family that includes omnivorous species, whereas all members of the families to which the cat and frog belong are carnivorous as adults. All three species were able to regulate rates of AA transport, though the patterns and magnitude of the responses differed between species as well as between AAs, suggesting independent regulation of some AA transporters.(ABSTRACT TRUNCATED AT 250 WORDS)

Quantification of two-year-old hybrid poplar root systems: morphology, biomass, and 14C distribution

Abstract: Root morphology, biomass, and (14)C distribution were studied in two 2-year-old Populus trichocarpa x P. deltoides hybrids, which originated from hardwood cuttings, to determine the pattern of root distribution in a plantation and to refine methods for root recovery. The trees were labeled with (14)CO(2) and harvested after a 72-hour chase period. Roots attached to each labeled tree were analyzed for morphological traits at the time of harvest. Detached roots from within a 1-m(3) volume of soil surrounding each tree were separated from the soil and sorted on the basis of rooting depth and root diameter. Lateral roots > 2 mm in diameter had a largely horizontal orientation at their point of origin from the cutting and extended horizontally up to 4 m from the cutting. This resulted in considerable overlap of root systems in the plantation. Results from (14)C labeling indicated that 24 +/- 4% (+/- SD) of the carbon exported from branches-labeled within two weeks after branch budset-was translocated to the root system. Dilution of the root (14)C label indicated that from 0 (> 5 mm diameter roots) to 75% (< 2 mm diameter roots) of the roots recovered from within the 1-m(3) volume of soil surrounding a harvested tree originated from other trees. Total root biomass was 6 +/- 1 Mg ha(-1) for both hybrids. Sixty percent of the root biomass was recovered directly from excavation, 16% from coarse-sieving excavated soil, and 24% from re-sorting sieved soil. The study indicated that root growth of hybrid poplars may be rapid and extensive and that detailed sorting of soil subsamples substantially improves the recovery of fine roots < 2 mm in diameter.

Chloroplast and mitochondrial mechanisms for protection against oxygen toxicity.

Abstract: As a consequence of their oxygen rich environment, organelles of photosynthetic tissues are exposed to large fluxes of oxyradicals and reactive oxygen species. Superoxide, hydrogen peroxide, hydroxyl radical and singlet oxygen are all potential by-products of respiratory and photosynthetic systems. Strong reduc-tants found in mitochondria and chloroplasts along with a steady flux of photosynthetically generated oxygen enhance the potential for oxyradical production. Unless ncturalized by scavenger substrates or enzymes, these reactive intermediates pose a lethal threat.The presence of superoxide dismutases, cdtalases. various peroxidases and scavenger substrates are all means of defences available to protect organelles. A balance between oxyradical production and neutralization should exist. Perturbations in generation or in sequestration caused by environmental or nutritional factors might profoundly alter the steady state level of oxyintermediates.

Evaluation of the flora and fauna of aSpartina alterniflora marsh established on dredged material in Winyah Bay, South Carolina

Abstract: Approximately 35 hectares ofSpartina alterniflora marsh has, over a 14-year period, developed naturally on unconfined dredged material placed within the intertidal zone of Winyah Bay, South Carolina. The above-and below-ground vegetative structure, benthic macrofauna, and resident fish and shellfish assemblages of two varying-aged zones (4 and 8 years) of this marsh were evaluated and compared in September 1988. Vegetative structure (stem height, density, percent cover, and biomass) in both zones was within the range reported for natural sites, with a trend toward greater below-ground development with age. The macrofaunal assemblages of both zones were similar in both species composition and numbers of species (17–21 species), with oligochaetes and polychaetes dominating both assemblages. Overall density of macrofauna in the 8-year-old zone (19,943 individuals per m2) was significantly greater than that in the 4-year-old zone (4,628 individuals per m2). Differences between zones (particularly the presence of large-bodied molluscs in the older site) seemed to reflect age. The fish and shellfish assemblage collected from the younger site was dominated byFundulus heteroclitus andPalaemonetes pugio. Gut contents ofF. heteroclitus included a variety of marsh-surface prey, similar to that reported elsewhere. Overall, both zones seemed to represent well established, viable, low intertidal marsh habitat.

Radiation-Controlled, Opposed-Flow Flame Spread in a Microgravity Environment

Abstract: The effects of surface and gas-phase radiation on the rate and the structure of laminar flame spread over thin fuels are investigated using a flame-spread model which consists of the continuity, momentum, species, and energy equations in the gas and the continuity and energy equations in the solid. Numerical calculations, complemented by scaling arguments, show that, at high velocities of the oxidizer flow, radiation effects are unimportant; the spread rate decreases with increasing opposing velocity due to finite-rate gas-phase kinetics. However, radiation becomes progressively important when the opposing velocity is below a certain value: the flame cools, shrinks in size, and its spread rate falls sharply with decreasing opposing velocity.

Algorithmic mapping of neural network models onto parallel SIMD machines

Abstract: Implementations of neural networks on programmable massively parallel computers are addressed. The methods are based on a graph theoretic approach and are applicable to a large class of networks in which the computations can be described by means of matrix and vector operations. A detailed characterization of the target machine is provided. Two mappings are presented. The first is designed for a processor array consisting of a very large number of small processing units. The neurons and the nonzero synaptic weights are assigned to the processors in a predetermined order, one per processor. The data transfers between processors containing neurons and weights are implemented using a novel routing algorithm. The second mapping is designed for the data array of size N*N and a smaller processor array of size P*P, P >

Effects of exogenous insulin and body condition on metabolic hormones and gonadotropin-induced follicular development in prepuberal gilts.

Abstract: To determine influences of insulin and body condition on follicular growth, prepuberal gilts (n = 16) treated with pregnant mare's serum gonadotropin (PMSG) were used in a 2 X 2 factorial experiment with main effects of insulin (0 or .4 IU/kg every 12 h beginning at 1800 on the day before PMSG) and backfat depth (moderate, 25 +/- .8; high, 32 +/- .7 mm; P less than .0001). Body weights were similar. Blood sampling was at 6-h intervals for analyses of LH, FSH, growth hormone (GH), glucagon, cortisol, insulin, insulin-like growth factor-I (IGF-I), plasma urea nitrogen (PUN), nonesterified fatty acids (NEFA), testosterone, estradiol-17 beta, and progesterone. Ovaries were removed 75 h after PMSG treatment, and visible small (less than or equal to 3 mm), medium (4 to 6 mm), large (greater than or equal to 7 mm), and macroscopically atretic follicles were counted. Administration of insulin increased IGF-I in fluid of medium follicles (108.8 vs 60.7 ng/ml; SEM = 13.3; P less than .05). Neither insulin nor fatness affected hCG binding by granulosa cells (12.5 +/- 1.6 ng/10(6) cells) or numbers of large (16.7 +/- 2.6) and medium (10.4 +/- 2.3) follicles. However, insulin increased the number of small follicles (58.9 vs 29.9; SEM = 9.7; P less than .05) and reduced the number of atretic follicles (3.8 vs 11.3; SEM = 1.1; P less than .05). The predominant effect of insulin on reducing number of atretic follicles was in the small size class (.6 vs 6.9; SEM = .6, P less than .01). Follicular fluid estradiol and progesterone were not affected by treatments; however, testosterone concentrations in large follicles were lower in gilts with higher backfat (32.5 vs 59.9 ng/ml; SEM = 4.0; P less than .05). Systemic LH, FSH, glucagon, cortisol, PUN, NEFA, estradiol, and testosterone were not affected by insulin or level of feeding. However, GH was lower in gilts that had higher backfat (overall average of 3.2 vs 2.8 ng/ml; SEM = .1; P less than .05). Insulin reduced atresia and altered intrafollicular IGF-I independently of body condition and without sustained effects on other hormones.

Acute effects of the organophosphate paraoxon on schedule-controlled behavior and esterase activity in rats: dose-response relationships.

Abstract: The effects of acute intraperitoneal administration of paraoxon on behavioral and biochemical parameters were studied in male rats. Rats were trained to press a lever under an FR10 schedule of reinforcement. Rats were injected with 3 sublethal doses of paraoxon (0.5, 0.75, and 1.0 mg/kg) and performance was monitored for four days after exposure. Response rates were depressed significantly for days 1 and 2 with 0.75 and 1.0 mg/kg, but not 0.5 mg/kg, even though there was inhibition of brain and plasma cholinesterases at all doses. Performance recovered prior to brain AChE recovery. There was no clear-cut threshold of brain AChE inhibition required to yield performance deficits, nor was there a direct correlation between significant inhibition in peripheral enzymes which could serve as markers (plasma aliesterases, butyrylcholinesterase, non-iso-OMPA-sensitive cholinesterase, and hepatic aliesterases) and performance deficits, suggesting that other noncholinergic targets may play a role in OP-induced behavioral deficits.

Euler flow predictions for an oscillating cascade using a high resolution wave-split scheme

Abstract: A compressible flow code that can predict the nonlinear unsteady aerodynamics associated with transonic flows over oscillating cascades is developed and validated. The code solves the two-dimensional, unsteady Euler equations using a time-marching, flux-difference splitting scheme. The unsteady pressures and forces can be determined for arbitrary input motions, although this paper will only address harmonic pitching and plunging motions. The code solves the flow equations on a H-grid which is allowed to deform with the airfoil motion. Predictions are presented for both flat plate cascades and loaded airfoil cascades. Results are compared to flat plate theory and experimental data. Predictions are also presented for several oscillating cascades with strong normal shocks where the pitching amplitudes, cascade geometry and interblade phase angles are varied to investigate nonlinear behavior.Copyright © 1991 by ASME

In vitro responses of channel catfish, Ictalurus punctatus, neutrophils to Edwardsiella ictaluri.

Abstract: The in vitro responses of channel catfish peripheral blood neutrophils to Edwardsiella ictaluri were examined through the use of phagocytic, bactericidal, and chemiluminescent assays. Evidence from both light and electron microscopy indicate that catfish neutrophils appeared to phagocytose E. ictaluri. Although extracellular killing of E. ictaluri was observed, bactericidal assays did not demonstrate intracellular killing of E. ictaluri by neutrophils. Catfish neutrophils mount a chemiluminescent response to E. ictaluri which is enhanced by the presence of specific antibody. Incubation of catfish neutrophils with LPS from E. ictaluri appeared to suppress the chemiluminescent response to opsonized zymosan.

Effect of an aperture on the spectrum of partially coherent light

Abstract: It is shown for a particular class of partially coherent fields that, when such a field is incident upon a circular aperture, the spectrum of the light at an observation point in the far zone of the aperture is different from the spectrum of the light in the aperture. An explicit expression for the spectrum at such observation points is obtained, and it is shown that the difference between the two spectra depends on the ratio of the radius of the aperture to the effective correlation length of the light in the aperture. Numerical examples are presented, and the relevant limiting cases are discussed.