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Articles 150601 - 150630 of 159709

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Distribution And Seasonal Occurrence Of The Scutelleridae, Corimelaenidae And Cydnidae Of Arkansas, Linda A. Lee, Harvey E. Barton Jan 1983

Distribution And Seasonal Occurrence Of The Scutelleridae, Corimelaenidae And Cydnidae Of Arkansas, Linda A. Lee, Harvey E. Barton

Journal of the Arkansas Academy of Science

A total of 16 genera and 37 species and subspecies of Corimelaenidae, Cydnidae and Scutelleridae is recorded as occurring or possibly occurring in Arkansas. Nine species of Scutelleridae contained in six genera, 13 species and subspecies in three genera of Corimelaenidae ( =Thyreocoridae) and 15 species and subspecies of Cydnidae found in seven genera are reported as occurring or possibly occurring in Arkansas. Twenty-seven species and subspecies contained in 13 genera were collected or recorded from entomological holdings within the state. Two species in two genera were reported in the literature as occurring in Arkansas. Based on distribution records in …


Computer Pattern Recognition Of Action Potentials, Ronald S. Remmel Jan 1983

Computer Pattern Recognition Of Action Potentials, Ronald S. Remmel

Journal of the Arkansas Academy of Science

A general method of pattern recognition was applied to the problem of recognizing extracellularly-recorded neuronal action potentials in the presence of noise and other pulses. A PDP1 1/23 performed the calculations. There were four stages: 1.) A bandpass filter attenuated noises; 2.) the data input program digitized the signal every 55 μsec. If the signal exceeded a threshold, 12 samples of the signal and the time were written onto the disk; 3.) the pulse discriminating program recognized an action potential by fitting the 12 points with this function: v(t) = (a + bt + ct² ) exp(-t/Ƭ). For each pulse …


Phytoplankton Community Structure In Dardanelle Reservoir, Arkansas, 1975-1982, John D. Rickett, Robert L. Watson Jan 1983

Phytoplankton Community Structure In Dardanelle Reservoir, Arkansas, 1975-1982, John D. Rickett, Robert L. Watson

Journal of the Arkansas Academy of Science

Phytoplankton data were collected with standard equipment and procedures over an eight-year period (1975-1982) in Dardanelle Reservoir, Arkansas. Community abundance and diversity at the genus level are described. Sixty-five genera representing 35 families and five divisions were identified. Total phytoplankton abundance and diversity were quite uniform among the stations but fluctuated considerably with time. These fluctuations did not correspond clearly with season. Dominant taxa were seasonal, though, with diatoms being usually dominant in January, April and October, and blue-greens dominant in July. The phytoplankton community structure has not been significantly altered by the operation of ANO Unit I.


Zooplankton Community Structure In Dardanelle Reservoir, Arkansas, 1975-1982, John D. Rickett, Robert L. Watson Jan 1983

Zooplankton Community Structure In Dardanelle Reservoir, Arkansas, 1975-1982, John D. Rickett, Robert L. Watson

Journal of the Arkansas Academy of Science

Zooplankton was collected at 10 stations in Dardanelle Reservoir from 1975 to 1982. Current data were compared to a five-year preoperational study phase. Rotifer taxa strongly dominated the community. Overall abundance was higher, variety about the same and diversity lower than those of comparable studies. Thermal discharges caused a dominance shift between two rotifer taxa, slightly depressed abundance and variety, did not noticeably affect diversity and elevated the phytoplankton/zooplankton ratio. Heated effluent also stimulated stronger fluctuations in abundance and variety. Other studies indicate that in upper sections of the Arkansas River drainage, microcrustaceans dominate lake habitats whereas rotifers dominate river …


Fishes Of The Antoine River, Little Missouri River System, Southwestern Arkansas, Henry W. Robison, Elaine Laird, Darryl Koym Jan 1983

Fishes Of The Antoine River, Little Missouri River System, Southwestern Arkansas, Henry W. Robison, Elaine Laird, Darryl Koym

Journal of the Arkansas Academy of Science

The fishes of the Antoine River (Little Missouri River system) in southwestern Arkansas were surveyed from September, 1980 - June, 1982. Thirty-four field collections plus literature and museum records, revealed a total of 60 species in 29 genera representing 16 families to presently inhabit the river system. Comments are presented on life history aspects, systematics and occurrence of fishes in the study area.


Range Extension Of The Silver Carp, Hypophthalmichthys Molitrix, F. Allen Carter, John K. Beadles Jan 1983

Range Extension Of The Silver Carp, Hypophthalmichthys Molitrix, F. Allen Carter, John K. Beadles

Journal of the Arkansas Academy of Science

No abstract provided.


Sicklefin Chub, Hybopsis Meeki, In The Mississippi River Bordering Arkansas, F. Allen Carter, John K. Beadles Jan 1983

Sicklefin Chub, Hybopsis Meeki, In The Mississippi River Bordering Arkansas, F. Allen Carter, John K. Beadles

Journal of the Arkansas Academy of Science

No abstract provided.


Repair Of Ultraviolet And Gamma-Ray Induced Lethal Damage In An Insect Tissue Culture Cell Line, Craig Endres, Susan Kulp, H. Gaston Griggs Jan 1983

Repair Of Ultraviolet And Gamma-Ray Induced Lethal Damage In An Insect Tissue Culture Cell Line, Craig Endres, Susan Kulp, H. Gaston Griggs

Journal of the Arkansas Academy of Science

No abstract provided.


Preliminary Report On The Zygoptera (Damselflies) Of Arkansas, George L. Harp Jan 1983

Preliminary Report On The Zygoptera (Damselflies) Of Arkansas, George L. Harp

Journal of the Arkansas Academy of Science

No abstract provided.


Aquatic Macroinvertebrates Of The Hiatt Prairie Region, Franklin County, Arkansas, Julie A. Huggins, George L. Harp Jan 1983

Aquatic Macroinvertebrates Of The Hiatt Prairie Region, Franklin County, Arkansas, Julie A. Huggins, George L. Harp

Journal of the Arkansas Academy of Science

No abstract provided.


Development Of Tissue Culture Systems For The Evaluation Of Cancer Chemotherapeutic Agents, Clifton Orr, Joseph E. Stone, Maxine L. Polk Jan 1983

Development Of Tissue Culture Systems For The Evaluation Of Cancer Chemotherapeutic Agents, Clifton Orr, Joseph E. Stone, Maxine L. Polk

Journal of the Arkansas Academy of Science

No abstract provided.


First Report Of Brazilian Free-Tailed Bat Maternity Colonies In Arkansas, David A. Saugey, Darrell R. Heath, Clark Efaw, Gary A. Heidt, Teresa E. Beggs Jan 1983

First Report Of Brazilian Free-Tailed Bat Maternity Colonies In Arkansas, David A. Saugey, Darrell R. Heath, Clark Efaw, Gary A. Heidt, Teresa E. Beggs

Journal of the Arkansas Academy of Science

No abstract provided.


New County And State Records Of Mosses From Arkansas, Steve L. Timme, Jewel E. Moore Jan 1983

New County And State Records Of Mosses From Arkansas, Steve L. Timme, Jewel E. Moore

Journal of the Arkansas Academy of Science

No abstract provided.


Mosquitofish Production In Monoculture And Polyculture Ponds, Walter R. Robison, Scott H. Newton, Max V. Meisch Jan 1983

Mosquitofish Production In Monoculture And Polyculture Ponds, Walter R. Robison, Scott H. Newton, Max V. Meisch

Journal of the Arkansas Academy of Science

No abstract provided.


Observaciones Sobre La Biología De Phyllomedusa Iheringi Boulenger, 1885, (Anura, Hylidae), Rafael O. De Sá, Annelise Gerhau Jan 1983

Observaciones Sobre La Biología De Phyllomedusa Iheringi Boulenger, 1885, (Anura, Hylidae), Rafael O. De Sá, Annelise Gerhau

Biology Faculty Publications

RESUMEN:

Se presentan las características que permiten diferenciar las larvas de Phyllomedusa iheringi de las de otros anuros que habitan en nuestro territorio, junto con algunas observaciones sobre la biología de esta especie poco conocida en el Uruguay.

SUMMARY:

The characteristics that differentiate the larvae of Phyllomedusa iheringi from other anurans that live in Uruguay are presented here. Some observations on the biology of this species are also recorded.


Effects Of Sewage Pollution In The White River, Arkansas, Arthur V. Brown, Lawrence D. Willis, Peter P. Brussock Jan 1983

Effects Of Sewage Pollution In The White River, Arkansas, Arthur V. Brown, Lawrence D. Willis, Peter P. Brussock

Journal of the Arkansas Academy of Science

Recently there has been much emphasis placed on the importance of leaf detritus processing to the energetics of stream invertebrates. This study was designed primarily to assess the effects of municipal effluent on the ability of a stream community to utilize leaf detritus, and secondarily to evaluate the extent of the pollution of the White River by the Fayetteville, Arkansas, effluent discharge. Physical and chemical water quality and benthos were sampled periodically at one station upstream and two stations downstream from the discharge, and in the Richland Creek tributary. Processing of leaf detritus was also studied at each site using …


Selection Of Scales For Growth Analysis Of Largemouth Bass, Donald C. Jackson, Raj V. Kilambi Jan 1983

Selection Of Scales For Growth Analysis Of Largemouth Bass, Donald C. Jackson, Raj V. Kilambi

Journal of the Arkansas Academy of Science

Scales from four regions of the body of largemouth bass were compared for efficacy in estimating fish length at the time of scale formation and at capture. The scales from above and below the lateral line in the pectoral and caudal peduncle regions yielded intercepts of 64.73, 52.36, 19.77 and 25.81 respectively for the total length-scale radius relationship. These intercept values represent the fish length at the time of scale formation. By the regression of estimated lengths at capture on empirical lengths it was found that the caudal peduncle scales were better suited in predicting fish length.


Comparison Of Two Year Classes Of Hybrid Grass Carp And Grass Carp For Aquatic Plant Control, Mike Freeze, Scott Henderson Jan 1983

Comparison Of Two Year Classes Of Hybrid Grass Carp And Grass Carp For Aquatic Plant Control, Mike Freeze, Scott Henderson

Journal of the Arkansas Academy of Science

Two year classes of grass carp and F, hybrids resulting from bighead carp male x grass carp female were compared at various stocking densities for aquatic plant control. One and two year old grass carp exhibited higher survival rates and better growth rates than the same age hybrid grass carp. The presence of grass carp or hybrid grass carp decreased both Secchi disc transparencies and dissolved oxygen values. Grass carp had a greater negative effect upon these measurements because they removed the vegetation quicker than the hybrid grass carp. These apparent detrimental effects on water quality are necessary trade-offs for …


Short Creek Oolite (Lower Mississippian) Deposition, War Eagle Quarry, Madison County, Arkansas, Barbara A. Lisle Jan 1983

Short Creek Oolite (Lower Mississippian) Deposition, War Eagle Quarry, Madison County, Arkansas, Barbara A. Lisle

Journal of the Arkansas Academy of Science

The Short Creek Oolite is the only formally designated member of the Lower Mississippian Boone Formation. Although oolite deposits are often considered to be formed in shoal areas, detailed study of the War Eagle Short Creek disclosed characteristics incompatible with deposition as an oolite shoal. At the War Eagle Quarry, the Short Creek Oolite occurs between deep water strata and there is a conspicuous absence of cross-stratification and other shallow water bedding features. Modal analysis revealed a lower oolith content than found in Recent oolite shoals or in the Short Creek Oolite of Missouri, which has been interpreted as a …


Abundance And Seasonal Occurrence Of Psorophora Columbiae In A Northeast Arkansas Ricefield Community, Larry A. Olson, Julia A. Huggins Jan 1983

Abundance And Seasonal Occurrence Of Psorophora Columbiae In A Northeast Arkansas Ricefield Community, Larry A. Olson, Julia A. Huggins

Journal of the Arkansas Academy of Science

Increased population levels of the dark ricefield mosquito, Psorophora columbiae (Dyar and Knab), have been shown to be associated with rice cultivation in Arkansas and several other states. Four standard New Jersey light traps were operated daily between May 30 and October 2 of 1981 and 1982 to determine the relative abundance and seasonal occurrence of this species in NE Arkansas. The effect of trap distance from nearby rice on the number of adult P. columbiae collected was assessed by comparing weekly totals from 2 traps located within 0.9 km of rice fields with totals from 2 traps situated beyond …


Arkansas Range Extensions Of The Seminole Bat (Lasiurus Seminolus) And Eastern Big-Eared Bat (Plecotus Rafinesquii) And Additional County Records For The Hoary Bat (Lasiurus Cinereus), Silver-Haired Bat (Lasionycteris Noctivagans) And Evening Bat..., Darrell R. Heath, Gary A. Heidt, David A. Saugey, V. Rick Mcdaniel Jan 1983

Arkansas Range Extensions Of The Seminole Bat (Lasiurus Seminolus) And Eastern Big-Eared Bat (Plecotus Rafinesquii) And Additional County Records For The Hoary Bat (Lasiurus Cinereus), Silver-Haired Bat (Lasionycteris Noctivagans) And Evening Bat..., Darrell R. Heath, Gary A. Heidt, David A. Saugey, V. Rick Mcdaniel

Journal of the Arkansas Academy of Science

No abstract provided.


Bryophyte-Lichen Communities Within Hot Springs National Park, Arkansas I., Jewel E. Moore, Steve L. Timme Jan 1983

Bryophyte-Lichen Communities Within Hot Springs National Park, Arkansas I., Jewel E. Moore, Steve L. Timme

Journal of the Arkansas Academy of Science

No abstract provided.


First Host Plant Records For Chelysomidea Guttata (Herrich-Schaeffer) (Hemiptera: Scutelleridae, With Notes On The Biology And Distribution, Julia L. Reid, Harvey E. Barton Jan 1983

First Host Plant Records For Chelysomidea Guttata (Herrich-Schaeffer) (Hemiptera: Scutelleridae, With Notes On The Biology And Distribution, Julia L. Reid, Harvey E. Barton

Journal of the Arkansas Academy of Science

No abstract provided.


On The Distribution And Characteristics Of Isozyme Expression In Mycoplasma, Acholeplasma, And Ureaplasma Species, Stephen J. O'Brien, Janice M. Simonson, S. Razin, Michael F. Barile Jan 1983

On The Distribution And Characteristics Of Isozyme Expression In Mycoplasma, Acholeplasma, And Ureaplasma Species, Stephen J. O'Brien, Janice M. Simonson, S. Razin, Michael F. Barile

Biology Faculty Articles

A summary of a survey of three genera of mycoplasmatales (Mycoplasma, Acholeplasma, and Ureaplasma) for isozyme expression is presented. Isozyme analysis of mycoplasmas has been employed in at least three distinct areas: (1) as genetic markers for identification, individualization, and taxonomic classification; (2) as markers for cell culture contamination; and (3) as a qualitative measure of the operative metabolic pathways in the diverse species. We have found five ubiquitous enzymes: purine nucleoside phosphorylase, adenylate kinase, inorganic pyrophosphatase, dipeptidase, and esterase. Three enzymes, glucose-6-phosphate dehydrogenase, phosphogluconate dehydrogenase, and superoxide dismutase, were restricted to Acholeplasma species and were not …


Introgressive Hybridization In A Population Of Astyanax Fasciatus (Pisces: Characidae) At La Cueva Chica, Aldemaro Romero Jr. Jan 1983

Introgressive Hybridization In A Population Of Astyanax Fasciatus (Pisces: Characidae) At La Cueva Chica, Aldemaro Romero Jr.

Publications and Research

No abstract provided.


Physiology Of Male Reproduction, R. P. Amann, B. D. Schanbacher Jan 1983

Physiology Of Male Reproduction, R. P. Amann, B. D. Schanbacher

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

The major advances over the past 25 yr in male reproductive physiology of cattle, sheep, swine and horses are reviewed. Those findings which have allowed efficient culling of subfertile males and exploitation of the reproductive capacity of genetically superior sires are emphasized.

Hormones secreted by the male gonad early in gestation induce regression of potentially female structures and development of the male reproductive tract. Compartmentalization of the testis and formation of the bloodtestis barrier during prepubertal development permit the steroidogenic and gametogenic activities of the adult testes to proceed normally. The role of the central nervous system, hypothalamus and anterior …


Reproductive Effects Of Immunizing Heifers Against Androstenedione And Oestradiol-17Β, T. H. Wise, B. D. Schanbacher Jan 1983

Reproductive Effects Of Immunizing Heifers Against Androstenedione And Oestradiol-17Β, T. H. Wise, B. D. Schanbacher

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Heifers were treated with saline (Group I, N = 10), keyhole limpet haemocyanin (KLH ; Group II, N = 10), androstenedione-KLH antigen (Group III, N = 14), or oestradiol-17β-KLH antigen (Group IV, N = 14). Booster injections were given to produce binding of > 10% at dilutions of 1:100 to 1:1000 (50% binding = 14·4pg androstenedione and 9·5pg oestradiol). The heifers were mated and killed at ~46days of gestation to establish ovulation rates, calf numbers, blood hormone relationships and ovarian morphology.

Ovulation rate in animals immunized against androstenedione (Group III) was significantly greater than in the other groups; 4 of the …


Water Conservation Of The Kangaroo Rat, Dipodomys Ordii, W. Sue Fairbanks, David Greegor, Leonard Staudinger, Erik Bitterbaum Jan 1983

Water Conservation Of The Kangaroo Rat, Dipodomys Ordii, W. Sue Fairbanks, David Greegor, Leonard Staudinger, Erik Bitterbaum

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

Kangaroo rats (Dipodomys spp.) have long been known for their water-conserving abilities. Dipodomys ordii is the most widely distributed kangaroo rat in the United States and its range extends through many climates. Five D. ordii from the Nebraska Sand Hills were used in this experiment. The results of this study indicate that Dipodomys ordii is not independent of free water, but does have a urine concentrating ability comparable to D. merriami, a desert-dwelling species. The individuals showed variability in their response to water deprivation.


The Relationship Of Science To The North-South Dialogue, William N. Hubbard Jr. Jan 1983

The Relationship Of Science To The North-South Dialogue, William N. Hubbard Jr.

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

The dialogue between the Northern and Southern hemispheres of this one Earth is concerned with the issue of human equity. It is the dialogue between those in the north who have an abundance of goods and services, with a generally improving opportunity for self-fulfillment, as contrasted with those in the south who are deficient in even rudimentary goods and services and whose opportunity for self-fulfillment is not only smaller than their brothers' in the north but is probably diminishing.

The mind·numbing plight of the poorest of the poor in this world shall not be inventoried in any detail. The absolute …


Biographical Sketch And Contributions To Medicine Of Xavier Bichat, Anne J. Krush Jan 1983

Biographical Sketch And Contributions To Medicine Of Xavier Bichat, Anne J. Krush

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

Xavier Bichat was born in Thoirette, France, on 11 November 1771, the oldest son of Jean-Baptiste Bichat, a physician. As a young man, Bichat went to the city of Lyon and became the pupil of a surgeon, M.-A. Petit. In 1793, he went to the Hôtel-Dieu Hospital and studied under the surgeon, P.-J. Desault; they became close friends. Desault died at age 47 in 1795 leaving unfinished a four-volume manuscript on surgery. Faithfully, Bichat completed this work. Bichat was named Physician of Hôtel-Dieu Hospital at 1ge 28. There, he continued his research on cadavers and treatment of patients; his writing …