Showing papers by "Mississippi State University published in 1978"
TL;DR: In this article, the authors review existing methods for analyzing experimental design models with unbalanced data and to relate them to existing computer programs, distinguished by the hypotheses associated with the sums of squares which are generated, rather than on computational convenience or the orthogonality of the quadratic forms.
Abstract: The objective of this article is to review existing methods for analyzing experimental design models with unbalanced data and to relate them to existing computer programs The methods are distinguished by the hypotheses associated with the sums of squares which are generated The choice of a method should be based on the appropriateness of the hypothesis rather than on computational convenience or the orthogonality of the quadratic forms The sums of squares are described using the R ( ) notation as applied to the over-parameterized linear model, but the hypotheses are stated in terms of the full-rank cell means model The zero-cell frequency situation is treated briefly
151 citations
TL;DR: Higher mortality and larger market broiler weights were found when chicks were hatched from either 57—62 or 67—74 gram eggs compared to chicks hatched from 47—54 gram eggs, and no significant differences in market body weights due to age of parents were found.
105 citations
TL;DR: None of the gross pathological changes previously reported for tryptophan deficiency in sockeye salmon and rainbow trout were observed in channel catfish.
Abstract: Growth studies, utilizing a 24% crude protein diet containing an amino acid pattern similar to whole egg protein, indicate that the tryptophan requirement for fingerling channel catfish (Ictalurus punctatus) is about 0.12% of the diet (dry weight basis) or 0.5% of the dietary protein. Similar studies indicate that the threonine requirement for the same fish is about 0.53% of the diet (dry weight basis) or 2.21% of the dietary protein. The dietary requirement of threonine was confirmed by serum free threonine analysis. A marked increase in serum free threonine occurred at a dietary threonine level of approximately 0.5% of the diet. None of the gross pathological changes previously reported for tryptophan deficiency in sockeye salmon and rainbow trout were observed in channel catfish.
97 citations
TL;DR: In a four-week-old chicken .1 ml carbon solution was deposited on the vent and sucked into the lumen of the bursa and absorbed by the follicular epithelium which appeared as black dots on the surface of the folds which represented the number of follicles per fold.
84 citations
TL;DR: A multiple regression analysis revealed that structural differences amongst edaphic diatom communities were related to differences in elevation, far red light energy, ammonia nitrogen, soil moisture, and tentatively, height of the spermatophyte canopy.
Abstract: Edaphic diatoms were collected on a seasonal basis from beneath five monospecific stands of spermatophytes on Graveline Bay Marsh (Mississippi) from 14 October 1976 through 21 June 1977. Of the 119 diatom taxa encountered. only seven were restricted to a single edaphic habitat, and five of these accounted for 17.2%of the individuals comprising the community associated with Distichlis spicata (L.) Greene. The single most abundant diatom was Navicula tripunctata (Müll.) Bory, which accounted for 21.5%of all individuals counted during the study. Based on a 2‐way ANOVA of species diversity (H’) and the number of taxa in a sample, edaphic diatom community diversity was highest beneath D. spicata and Spartina patens (Ait.) Muhl., lowest beneath Sp. alterniflora Loisel. and Juncus roemerianus Scheele, and somewhat intermediate for the Scirpus olneyi Gray habitat. Structural differences between selected community pairs were quantified using a similarity index (SIMI) and the values generated were exceedingly variable. A multiple regression analysis revealed that structural differences amongst edaphic diatom communities were related to differences in elevation, far red light energy, ammonia nitrogen, soil moisture, and tentatively, height of the spermatophyte canopy.
82 citations
TL;DR: In this article, a transformation method is developed which may be used to solve various types of boundary value problems on three-dimensional regions with an arbitrary boundary, and the implementation of the method is illustrated in the solution of a potential flow problem.
Abstract: A transformation method is developed which may be used to solve various types of boundary value problems on three-dimensional regions with an arbitrary boundary. The implementation of the method is illustrated in the solution of a potential flow problem. All computations are performed on a cubic mesh in a rectangular region.
63 citations
01 Jan 1978
TL;DR: Attention is given to the types of boundary-fitted coordinate systems, coordinate system control, operation of the coordinate codes, solution of partial differential equations, application to free-surface flow, and other applications of interest.
Abstract: The technique of boundary-fitted coordinate systems is based on a method of automatic numerical generation of a general curvilinear coordinate system having a coordinate line coincident with each boundary of a general multi-connected region containing any number of arbitrarily shaped bodies. Once the curvilinear coordinate system is generated, any partial differential system of interest can be solved on this coordinate system by transforming the equations and solving the resulting system in finite difference approximation on the rectangular transformed plane. This method of automatic body-fitted curvilinear coordinate generation is used to construct finite-difference solutions of the full, time dependent Navier-Stokes equations for the unsteady viscous flow about arbitrary two-dimensional airfoils, or any other two-dimensional bodies. Finally, initial results for three-dimensional applications are also presented.
60 citations
TL;DR: Light microscopy has revealed a possible secretory cell in the medulla of the bursa of Fabricius and Cyclophosphamide increased the presence of thesecretory cell.
Abstract: Light microscopy has revealed a possible secretory cell in the medulla of the bursa of Fabricius. Cyclophosphamide increased the presence of the secretory cell.
59 citations
TL;DR: Scores on all three test-anxiety measures showed that, under conditions of equivalent demand, the placebo procedure reduced self-reports of test anxiety at least as much as did cue-controlled relaxation.
Abstract: Twenty-eight test-anxious Ss received either "cue-controlled relaxation therapy," an inert placebo treatment, or no treatment. Once before and twice after the experimental treatment period each S responded to three test-anxiety scales and to one measure of public-speaking anxiety. Once after the treatment, Ss rated the credibility of the procedure to which they had been exposed. Pre- and posttreatment scores on the measure of (untreated) speech anxiety and posttreatment ratings of credibility both showed that the cued relaxation and placebo procedures exerted equivalent experimental demand for improvement. Scores on all three test-anxiety measures showed that, under these conditions of equivalent demand,the placebo procedure reduced self-reports of test anxiety at least as much as did cue-controlled relaxation. Implications are discussed.
52 citations
TL;DR: Antennae of the 4 nymphal instars and the alate and apterous virginoparous adults of pea aphid were studied and it is suggested that some of these antennal characters may aid in tracing phylogenetic relationships.
Abstract: Antennae of the 4 nymphal instars and the alate and apterous virginoparous adults of pea aphid ( Acyrthosiphon pisum (Harris)) were studied. Differences in antennal morphology as well as distribution and description of antennal sensilla are given. The first 2 nymphal instars possess 5 antennal segments, the others have 6. Total number of sensilla remains constant from second nymphal instar through adult. Scanning electron micrographs of sunken uniporous pegs of primary sensoria on segment 6 and openings to “rhinariellae” on segment 2 are presented for the first time. Comparisons are made of adult antennal characteristics of 17 species of aphids from 5 subfamilies. Microtrichia are absent from secondary sensoria, except in Drepanosiphinae and in 2 species of Aphidinae. Microtrichia are present around primary sensoria except in subfamilies Chaitophorinae and Lachninae. Thick walled hairs with enlarged tips are found in Drepanosiphinae and in the tribe Macrosiphini of Aphidinae. A new multiporous sensillum is described from members of the subfamily Drepanosiphinae. It is suggested that some of these antennal characters may aid in tracing phylogenetic relationships.
49 citations
TL;DR: A shift of cholesterol from the liver to the serum pool appeared to be responsible for the hypercholesterolemia observed in copper deficiency.
Abstract: The effect of copper deficiency on in vivo catabolism and excretion of [26-14C] cholesterol was studied in male rats. The study involved four treatments, namely, control, copper-deficient, control plus cholesterol, and copper-deficient plus cholesterol supplement. Significant elevations of serum ester and total cholesterol concentrations and reductions of serum free, ester, and total cholesterol specific activities were observed in rats fed the copper-deficient diets. In addition, a significant reduction of liver free cholesterol concentration was observed in rats fed the copper-deficient diets. Cholesterol supplementation significantly increased the concentrations of, and reduced the specific activities of, the different serum and liver cholesterol fractions. The only exception was that the liver free cholesterol concentration was not altered by cholesterol supplementation. The serum free cholesterol concentration was significantly increased and the specific activities of liver ester cholesterol were significantly reduced in rats fed the copper-deficient diet with no added cholesterol. The rates of oxidation and excretion of [26-14C] cholesterol were not influenced by dietary copper but were significantly increased by cholesterol supplementation. A shift of cholesterol from the liver to the serum pool appeared to be responsible for the hypercholesterolemia observed in copper deficiency.
TL;DR: Semiaquatic adaptations appear to be important components of niche segregation in these sympatric rodents, especially in cotton rats from Florida and Mississippi.
Abstract: The swimming ability of cotton rats and rice rats from several localities in Florida and Mississippi was compared. Rice rats freely swam a 2-m barrier separating two small “islands,” making better than 20 times the number of crossings made by cotton rats. Some cotton rats (26%) never swam the barrier during the 2-day test period, but all rice rats did. In general, cotton rats from Florida, especially ones from a barrier island, swam more frequently than did cotton rats from Mississippi. Rice rats from all localities were approximately equal in their tendency to swim. All crossings by rice rats and most by cotton rats were made during darkness. The fur of rice rats was more water repellent than that of cotton rats. Air trapped between hairs increased the buoyancy of the rice rats and reduced heat loss in water. Even with twice the body weight, cotton rats exhibited a significantly greater decrease in core body temperature when placed in 15°C water for 40 min than did rice rats. While swimming, both species used mainly the hind feet for propulsion and held the front feet close to the body. Rice rats swam faster than cotton rats, frequently swimming underwater for more than 10 m. Cotton rats never swam underwater, although they would momentarily submerge when they jumped from a platform. Semiaquatic adaptations appear to be important components of niche segregation in these sympatric rodents.
TL;DR: Growth and feed efficiency data indicate that channel catfish can utilize DL-methionine as effectively as L-mETHionine, and OH-M was only about 26% as effective in promoting growth as L.meth ionine.
Abstract: Sixteen isonitrogenous, isoenergetic diets were fed to fingerling channel catfish to study the efficacy of L-methionine, DL-methionine, methionine hydroxy analogue (OH-M), taurine and sodium sulfate. The basal diet contained casein and gelatin supplemented with crystalline L-amino acids to correspond to the amino acid pattern found in 24% crude protein from whole egg powder. The basal diet, containing 0.26% methionine was supplemented with graded levels of each of the sulfur sources on an isosulfurous basis. Growth and feed efficiency data indicate that channel catfish can utilize DL-methionine as effectively as L-methionine. OH-M was only about 26% as effective in promoting growth as L-methionine. No significant growth response was observed when taurine or inorganic sulfate was added to the basal diet.
TL;DR: Conidia of Nomuraea rileyi germinated in 2 days on larvae of Heliothis zea and appeared to be aided by enzymatic secretions as evidenced by the darkening of the epicuticle and part of the exocuticle suggesting apparent lysis.
TL;DR: Electrical recordings from the rostral nerve show increased impulse activity to stimulation of the roStral tip sensilla with juice from frego bract and normal bract squares of three varieties of cotton, confirming their function as contact chemoreceptors.
Abstract: The rostral tip of the tarnished plant bug contains two sensory fields each containing eleven sensilla basiconica. Removal of the rostral tip or antennae abolishes a feeding preference for frego bract cotton squares, suggesting that receptors at these loci are essential for a normal behavioral choice. Electrical recordings from the rostral nerve show increased impulse activity to stimulation of the rostral tip sensilla with juice from frego bract and normal bract squares of three varieties of cotton, confirming their function as contact chemoreceptors. Histograms of impulse frequency against time exhibit differences among the three cotton varieties tested.
RESUME
CHIMIORECEPTION DE CONTACT CHEZ LYGUS LINEOLARIS
Cette etude a ete entreprise pour determiner si les sensilles situees a l'extremite du labium chez Lygus lineolaris sont des chimiorecepteurs importants pour le comportement alimentaire de cet insecte. Des microscopies electroniques a balayage revelent deux champs sensoriels a l'extremite rostrale, chacun contenant 11 sensilles basiconiques d'environ 4 μm de longueur. Au-dessous se trouvent 2 sensilles trichoides (14 μm) situees ventralement, et un anneau de 6 sensilles trichoides (10 μm) situees proximalement par rapport aux precedentes. L'extirpation de l'extremite rostrale ou des antennes abolit la preference pour les carres de frego bractees de coton dans un test de choix. Des enregistrements electriques au niveau du nerf rostral confirment que les soies trichoides sont des mecanorecepteurs et les basiconiques des chimiorecepteurs de contact. La stimulation des basiconiques avec le jus provenant de carres de frego bractees et de bractees normales de 3 varietes de coton a eu dans tous les cas pour resultat une augmentation des niveaux de frequence des impulsions. Des histogrammes de frequence des impulsions/temps ont montre des differences dans les amplitudes de leurs parties phasees, dans les taux de baisse de la frequence et dans le temps auquel ce taux approchait de zero.
TL;DR: An inbreeding study of the polyploid fern Ceratopteris shows segregation of a marker characterized by pale green gametophytes, and a model based upon a duplicated locus and homoeologous chromosome pairing can explain the segregational behavior.
Abstract: The segregation of a marker characterized by pale green gametophytes was monitored within an inbreeding study of the polyploid fern Ceratopteris. Although all of the sporophytes showing segregation were derived from the self-fertilization of haploid gametophytes, a low overall frequency of 2.5% pale gametophytes was observed in the F3-F5 generations. A model based upon a duplicated locus and homoeologous chromosome pairing can explain the segregational behavior within the study. The overall level of homoeologous pairing was determined to be 10%. Occasionally, green gametophytes that were presumably heterozygous for the marker contained pale sectors. This behavior may
TL;DR: In this paper, the authors studied the oscillatory behavior of the solutions of the perturbed second-order nonlinear differential equation (a(t) x, f q(t, x) = qt, t, x, x).
TL;DR: A scanning electron microscope was used to compare the proximal region (PR) and distal region (DR) of the caecum and revealed segmented structures attached to the surface of PR to be bacteria.
TL;DR: Analyses of the steam-distillable oils of male and female tarnished plant bugs, Lygus lineolaris, with an integrated gas chromatography-mass spectrometry system showed that most of the compounds were esters.
TL;DR: In this paper, properties of a transformation method, which was developed for solving fluid dynamic problems on general two dimensional regions, are discussed, including construction error of the transformation and applications to mesh generation, and an error and stability analysis for the numerical solution of a model parabolic problem is also presented.
TL;DR: The homosporous fern Ceratopteris thalictroides (Parkeriaceae) has evolved a polyploid genetic system that serves to store and release genetic variability in spite of self-fertilization and Mendelian homozygosity.
Abstract: The homosporous fern Ceratopteris thalictroides (Parkeriaceae) has evolved a polyploid genetic system that serves to store and release genetic variability in spite of self-fertilization and Mendelian homozygosity. This is demonstrated by the segregation of a gametophyte mutant within two inbred tetraploid lines and in their intraspecific hybrid. The segregation behavior can be explained by a model involving a duplicated locus and regular homoeologous chromosome pairing. Homoeologous pairing occurs at low levels in the inbred lines and at a high level in the hybrid, indicating intraspecific differences in chromosome pairing affinities.
TL;DR: Characteristics of sorghum plants which result in the highest animal productivity per unit of land area are suggested.
TL;DR: The salinity of interstitial water was examined at 11 equidistant stations along a transect on a Mississippi tidal marsh dominated byJuncus roemerianus andSpartina cynosuroides as discussed by the authors.
Abstract: The salinity of interstitial water (i.e., the salinity of the free soil water) was examined at 11 equidistant stations along a transect on a Mississippi tidal marsh dominated byJuncus roemerianus andSpartina cynosuroides. Changes in the nearby surface water (e.g., bay water) were reflected in the changes in interstitial water salinity. The salinity of interstitial water was usually higher, varying between 2.5 and 15.8‰ from February 1975 through January 1976, than the salinity of the nearby surface water which ranged from 0.0 to 11.5‰. Following a long period of high salinity in the bay and sound (exceeding 14‰), the salinity of the interstitial water increased to a maximum of 16.8‰ in October. The salinity increased as the distance of the sampling station from the source of the flood water increased. Mean interstitial wate salinity across the marsh studied was within 10‰ which did not seem to influence the marsh plant zonation occurring on the marsh.
TL;DR: Although sequential sampling plans have been developed for other uses such as quality control and the estimation of organisms other than insects, this review is devoted primarily to sequential sampling Plans developed for estimating insect populations.
Abstract: Sequential sampling, in which the number of samples required to classify an insect population level is determined as sampling progresses, was developed during World War II. Because of its value, sequential sampling was classified as restricted and was not made available for wider use until after World War II (Wald 1945, 1947, Statistical Research Group 1946). Forest entomologists were among the first to use sequential sampling in estimating insect populations (Stark 1952, Ives 1954, Morris 1954 and Waters 1955). The 1st applications of sequential sampling in agricultural entomology were reported later by Sylvester and Cox (1961), Wolfenbarger and Darroch (1965), and Harcourt (1966). Although sequential sampling plans have been developed for other uses such as quality control and the estimation of organisms other than insects, this review is devoted primarily to sequential sampling plans developed for estimating insect populations. Furthermore, the references cited herein include only those sequential sampling plans which can be used to classify populations into broad population levels.
TL;DR: Evidence for the transformation of a blood-borne progenitor cell to bursal lymphocyte has been reviewed and the elegant experiments of LeDouarin, using interspecies chimeras, will be discussed to extend the previous review.
01 Jan 1978
TL;DR: In this article, the hypotheses associated with the R( ) notation for general sets of conditions are described in terms of the means of the observed populations, and the discussion is restricted to two-way models.
Abstract: The purpose of this paper is to describe the hypotheses commonly tested in linear models with unbalanced data, including the case of zero cell frequencies Historically, the sums of squares for the test statistics have been developed either on heuristic principles or because of computational convenience Precise statements of the corresponding hypotheses are rarely found in the literature and, in those cases where the hypotheses are stated, they are usually described in terms of the parameters of the non-full rank model which may be difficult to interpret In this paper, the hypotheses associated with the R( ) notation for general sets of conditions are described in terms of the means of the observed populations The discussion is restricted to two-way models, but the concepts are quite general Examples are included to illustrate the hypotheses tested with missing cells
TL;DR: Mirex residue in the liver of male rats was most closely correlated with hepatic lipid concentration but was not significantly correlated in females, and sex hormones were apparently involved in the magnitude of the liver response.
TL;DR: In this paper, it was shown that the O-H moiety has both the gauche and trans conformations present in the equatorial form but only the conformer is present in axial form of the ring.
TL;DR: In this paper, four norms are developed which seem suitable for testing the scope and definition of marketing: the level of abstraction norm, the norm of correspondence, the pragmatic norm, and norm of simplicity.
Abstract: The debate over the nature and scope of marketing is far from settled, but the desire for change among marketers is apparent. It is urgent that marketers determine what the scope of their field should become as a necessary first step in developing an adequate definition. The effort so far has been somewhat haphazard with a variety of authors-extolling the virtues of their viewpoint. This article represents an attempt to add order to the search for a useful scope for marketing. To achieve this purpose, four norms are developed which seem suitable for testing the scope and definition of marketing. They include the level of abstraction norm, the norm of correspondence, the pragmatic norm, and the norm of simplicity. These four norms are first used to test two extreme positions and then to test a third compromise definition of marketing.