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University of Arkansas, Fayetteville

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Articles 5341 - 5370 of 5634

Full-Text Articles in Life Sciences

Utilization Of Nest Boxes By The Southern Flying Squirrel, Glaucomys Volans, In Central Arkansas, Gary A. Heidt Jan 1977

Utilization Of Nest Boxes By The Southern Flying Squirrel, Glaucomys Volans, In Central Arkansas, Gary A. Heidt

Journal of the Arkansas Academy of Science

Thirty-five nest boxes were placed 4.5-5.5 meters above the ground in an eight acre mixed pine-hardwood plot 20 km SE of Bryant, Saline County, Arkansas. These boxes were monitored from February, 1972, to May, 1975. Flying squirrels used the boxes between October and May, probably returning to den trees during the hotter period of the year. A total of 30 squirrels (18 males and 12 females) were marked by ear notching during the three year period. The winter population of the study area was estimated to be between 10 and 15 squirrels. It was not uncommon to find eight or …

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Dragonflies Of (Anisoptera) Arkansas, George L. Harp, John D. Rickett Jan 1977

Dragonflies Of (Anisoptera) Arkansas, George L. Harp, John D. Rickett

Journal of the Arkansas Academy of Science

Previous publications have recorded 69 species of dragonflies for Arkansas. Three of these are deleted, but state records for 21 new species are reported herein, bringing the list to 87 species. Based on lists from adjacent states, an additional nine species are listed as probably occurring in Arkansas. County records are given for both naiads and adults of each species, as well as first and last capture dates for adults. Specific location and capture date are given for new state records when such data are available. The most species (39) have been reported from Washington County. Twenty-nine counties list from …

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Effects Of 2, 4, 5-Trichlorophenoxyacetic Acid On Swiss-Webster Mice, Gerald S. Greer Jan 1977

Effects Of 2, 4, 5-Trichlorophenoxyacetic Acid On Swiss-Webster Mice, Gerald S. Greer

Journal of the Arkansas Academy of Science

Pure and Commercial samples of the herbicide 2,4,5-trichlorophenoxyacetic acid (2,4,5- T) were tested on Swiss-Webster mice for: (1) interruption of the estrus cycle and (2) teratogenic effects. The estrus cycle of mice administered Commercial 2,4,5-T was interrupted in 42.9% of the animals and in 12.5% of the animals given Pure 2,4,5-T. No fetal abnormalities were found in pregnant animals treated with Commercial or Pure 2,4,5-T. Fetal resorptions were found in both treatment groups. Treatment with Pure 2,4,5-T produced a significant decrease in viable fetal weight and increased fetal deaths.

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Fishes Of Crowley's Ridge In Arkansas, Robert F. Fulmer, George L. Harp Jan 1977

Fishes Of Crowley's Ridge In Arkansas, Robert F. Fulmer, George L. Harp

Journal of the Arkansas Academy of Science

Crowley's Ridge is one of the six natural geographic divisions of Arkansas which rises out of the Mississippi embayment as a relatively steep, uncultivated loessial mass. The ridge is drained by a network of headwater streams which are relatively clear with alkaline pH values and uniformly low alkalinity values. Carbon dioxide values were moderate and oxygen values were adequate. The fish species collected were basically headwater in composition. Isolated groups of characteristically upland species indicate that environmental quality of adjacent deltaic streams was better at one time.

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Fishes Of Sylamore Creek, Stone County, Arkansas, George C. Frazier, John K. Beadles Jan 1977

Fishes Of Sylamore Creek, Stone County, Arkansas, George C. Frazier, John K. Beadles

Journal of the Arkansas Academy of Science

A survey of the fishes of Sylamore Creek in northcentral Arkansas yielded a total of 15,041 specimens representing 44 species, including one hybrid, distributed among 11 families. The three most abundant fishes collected were: Notropis pilsbryi Fowler, Dionda nubila (Forbes), and Notropis telescopus (Cope), respectively. Two species, Campostoma anomalum pullum (Agassiz), and N. pilsbryi, were collected at every station. Sylamore Creek is a clear predominantely spring-fed stream that originate in the Ozark Mountains of northcentral Arkansas and empties into the White River 72.3 km above Bates vilie. Sylamore Creek is composed of two branches, North and South Sylamore, which comprise …

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Forest Communities Of Crowley's Ridge, G. Thomas Clark Jan 1977

Forest Communities Of Crowley's Ridge, G. Thomas Clark

Journal of the Arkansas Academy of Science

The forest communities of Crowley's Ridge in Arkansas were surveyed by sampling 22 selected stands which met predetermined criteria. The Importance Value (I.V.) for each woody species over one decimeter, diameter breast height (dbh), was derived from the combined values of relative density, relative dominance by basal area (B.A.), and relative frequency. Young trees under one decimeter, dbh, were assigned to three height classes from which frequency, density, and stratification data were derived. White Oak-Red Oak-Hickory is the general forest type. Its subdivisions: Oak-Hickory-Pine Forest, Mixed Oak-Hickory Forest, and White Oak-Beech Forest are advocated for practical field references. They are …

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Comparative Studies Of The Witch Hazels Hamamelis Virginiana And H. Vernalis, Jack L. Bradford, Daniel L. Marsh Jan 1977

Comparative Studies Of The Witch Hazels Hamamelis Virginiana And H. Vernalis, Jack L. Bradford, Daniel L. Marsh

Journal of the Arkansas Academy of Science

An investigation of Hamamelis vernalis Sarg. and H. Virginiana L. was begun in southwestern Arkansas in the tall of 1976. An overlap of flowering periods occurred from late November through December, affording the possibility of hybridization. At one site the two taxa flowered simultaneously only 30 yards apart. Variation occurs in both taxa and there is a degree of overlap in most characters, but the composite of diagnostic features distinguishes the two species. The hybrid origin of H. vernalis suggested by Jenne (1966) does not seem likely.

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Development Of Sporangia In Polypodium Aureum Var. Undulatum: Initial Scanning Electron Microscopial Observations, William R. Bowen, David Williams Jan 1977

Development Of Sporangia In Polypodium Aureum Var. Undulatum: Initial Scanning Electron Microscopial Observations, William R. Bowen, David Williams

Journal of the Arkansas Academy of Science

Preliminary SEM observations of developing sori of P. aureum revealed several potential areas for future ultrastructural (SEM and TEM) study, including ontogeny of sporangial initials, annulus differentiation, and sport wall development.

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Fishes Of Randolph County, Arkansas, Steve M. Bounds, John K. Beadles, Billy M. Johnson Jan 1977

Fishes Of Randolph County, Arkansas, Steve M. Bounds, John K. Beadles, Billy M. Johnson

Journal of the Arkansas Academy of Science

A survey of the fishes of Randolph County in northcentral Arkansas was made between June 1973 and March 1977. Field collections, literature records, and museum specimens revealed the ichthyofauna of Randolph County to be composed of 128 species distributed among 24 families. Cyprinidae was the largest family, being represented by 34 species while Percidae was represented by 24 species. Randolph County is composed of Ozark Uplands and Coastal Plain areas. All of the stream systems flow into the Black River system with the exception of Village Creek in the southeastern corner of the county which flows into White River. The …

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Yolk-Periblast Junction In Fundulus Heteroclitus, Claudia F. Bailey Jan 1977

Yolk-Periblast Junction In Fundulus Heteroclitus, Claudia F. Bailey

Journal of the Arkansas Academy of Science

The yolk of teleost eggs becomes covered with a syncytial periblast during embryonic development. Nutrients must be transported through the periblast before they are available to the embryo. Tranmission electron micrographs of thin sections and of freeze-fractured replicas show a number of features at the yolk-periblast junction which may be correlated with yolk transport. These features include vesicle formation and exchange, channelization and interdigitation.

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Oxygen Toxicity In The Mammalian Liver, Dennis A. Baeyens, M. J. Meier Jan 1977

Oxygen Toxicity In The Mammalian Liver, Dennis A. Baeyens, M. J. Meier

Journal of the Arkansas Academy of Science

The effect of hyperbaric oxygen tensions on the oxygen consumption of mouse liver homogenates was investigated. It was found that hyperbaric oxygen rapidly inhibits the oxidative metabolism of the mammalian liver. Mouse liver homogenate exposed to an oxygen tension of 3837.8 mm Hg for 30 minutes demonstrated a 50.6% reduction in oxygen consumption compared to controls exposed to nitrogen at ambient pressure. The effects of reduced glutathione as a protective agent against hyperbaric oxygen toxicity were also examined. Liver homogenates pretreated with reduced glutathione and exposed to hyperbaric oxygen tensions demonstrated greater activity than untreated controls. It is concluded that: …

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Scaled Chrysophyceae From Arkansas, Robert A. Andersen, Richard L. Meyer Jan 1977

Scaled Chrysophyceae From Arkansas, Robert A. Andersen, Richard L. Meyer

Journal of the Arkansas Academy of Science

An initial study of scaled chrysophytes from Arkansas is presented. Species include: Synura Petersenii f. Petersenii, S. spinosa f. spinosa, S. curtispina f. curtispina, S. curtispina f. reticulata, S. uvella, Mallomonas striata var. striata, M. pumilio var. pumilio, and Chrysosphaerella brevispina. Transmission electron micrographs of their siliceous scales are included.

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An Evaluation Of The Effects Of Dredging Within The Arkansas River Navigation System, Volume Iii-The Effects Upon The Zooplankton Associations, Edgar D. Short, Eugene H. Schmitz Jan 1976

An Evaluation Of The Effects Of Dredging Within The Arkansas River Navigation System, Volume Iii-The Effects Upon The Zooplankton Associations, Edgar D. Short, Eugene H. Schmitz

Arkansas Water Resources Center Technical Reports

The primary purpose of the zooplankton phase of the coordinated study was to attempt to evaluate the effects of dredging operations on the abundance, distribution, composition and complexity of the zooplankton communities within the aquatic system of the Arkansas River. The other phases of investigation include fish, macroinvertebrates, phytoplankton and some physico-chemical parameters. The lack of baseline data, needed for measurement of previous ecological conditions from which to detect past and future changes, proved to be a major impediment to any evaluation. Although the study involved only about 240 miles of the river in Arkansas, it should serve as an …

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Aeration, Phosphorous, And Lime Affect Nitrogen Mineralization In Imperfectly Drained Forest Soils, M. S. Bhangoo, D. J. Albritton, Eugene Shoulders Jan 1976

Aeration, Phosphorous, And Lime Affect Nitrogen Mineralization In Imperfectly Drained Forest Soils, M. S. Bhangoo, D. J. Albritton, Eugene Shoulders

Journal of the Arkansas Academy of Science

Unamended, limed, and phosphorus-enriched Caddo, Beauregard, and Wrightsville silt loams (A1 horizon) were incubated for six months at room temperature under two moisture regimes. At field capacity, unamended soils lost 0.7% of organic matter and converted 166 ppm of organic nitrogen to inorganic forms. Ninety-five percent of the converted nitrogen was present as N₄-H or NO₃-N. Limed and phosphorus-treated soils at field capacity lost about 1.0% of organic matter and accumulated 191 to 201 ppm of inorganic nitrogen. Submerged soils lost very little organic matter and accumulated only 24 to 28 ppm of inorganic nitrogen. There was a loss of …

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Macrobenthos Population Changes In Crystal Lake, Arkansas, Subsequent To Cage Culture Fish, James C. Adams, Raj V. Kilambi, William A. Wickizer, Arthur V. Brown Jan 1976

Macrobenthos Population Changes In Crystal Lake, Arkansas, Subsequent To Cage Culture Fish, James C. Adams, Raj V. Kilambi, William A. Wickizer, Arthur V. Brown

Journal of the Arkansas Academy of Science

A three-year study was conducted to determine the possible effects of cage culture of fish on the environment of Crystal Lake, Arkansas. The investigation consisted of three periods: pre- (November 1971-October 1972), during- (November 1972-October 1973), and post- (November 1973-October 1974) cage culture. Numbers and biomass of benthos per square meter for pre-, during-, and post-culture periods were 1353 (10.0g), 730 (8.8g), and 1028 (4.1g), respectively. Numerically, Chaoborus sp., Chironomidae, and Oligochaeta comprised more than 97%. Chaoborus was the most numerous organism before fish culture (>68%), but dominance shifted to the Oligochaeta (>58%) after culture.

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Distributional Records Of Amphibians And Reptiles From Coastal Plain Of Arkansas, Edmond J. Bacon Jr., Zane M. Anderson Jan 1976

Distributional Records Of Amphibians And Reptiles From Coastal Plain Of Arkansas, Edmond J. Bacon Jr., Zane M. Anderson

Journal of the Arkansas Academy of Science

Distribution of amphibians and reptiles in the West Gulf Coastal Plain and Mississippi Alluvial Plain is not well known because extensive collecting has not been done in these areas and data in museums have not been published. New distributional records for three salamanders (Desmognathus fuscus brimleyorum, Manculus quadridigitarus, Plethodon glutinosus glutinosus) , two anurans (Rana areolata circulosa, Scaphiopus holbrooki holbrooki), and one snake (Lampropeltis doliata amaura) are presented. Additional collecting will be necessary to determine the exact range and status of the secretive species.

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Continuation Of Mourning Dove Studies In Clark County, Arkansas, With Emphasis On Cyclical Behavioral Patterns, Thurman Booth, Fred L. Burnside Jr., Jan Burnside, Peggy Rae Dorris Jan 1976

Continuation Of Mourning Dove Studies In Clark County, Arkansas, With Emphasis On Cyclical Behavioral Patterns, Thurman Booth, Fred L. Burnside Jr., Jan Burnside, Peggy Rae Dorris

Journal of the Arkansas Academy of Science

In conjunction with the U.S. Department of Interior, Fish and Wildlife Service, the Henderson State University Biology Department has continued a study of mourning doves in Clark County, Arkansas, with emphasis on cyclical behavioral patterns. Three hundred forty-three mourning doves were baited, trapped, and banded to obtain information concerning age, sex, populations, retraps, abnormalities, migrations, trap injuries, cyclical behavioral patterns, and other factors.

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Characteristics And Behavior Of Guineafowl And Domesticated Chicken Hybrids, Earl L. Hanebrink Jan 1976

Characteristics And Behavior Of Guineafowl And Domesticated Chicken Hybrids, Earl L. Hanebrink

Journal of the Arkansas Academy of Science

The description, behavior, and morphologic measurements are presented for two hybrid crosses of domesticated chicken and guineafowl. The ease at which gallinaceous birds hybridize might warrant a closer look at the classification system. Possibly the number of families in the superfamily Phasianoidea should be reduced as some other researchers suggest.

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Composition Of Arkansas Grapes During Maturation, Cameron Jones, Dominic T.C. Yang, Thomas O. Whitley Jan 1976

Composition Of Arkansas Grapes During Maturation, Cameron Jones, Dominic T.C. Yang, Thomas O. Whitley

Journal of the Arkansas Academy of Science

Changes in organic acid and glucose content during maturation and ripening of grapes grown in Arkansas in 1973 are shown for four French hybrid varieties, S5279, S10878, SV23- 657, and S13053, and for four rotundifolia varieties, Scuppernong, Tarheel, Fry, and Magoon. In all varieties the concentrations of malates and tartrates were highest in the early stages of berry growth after veraison. During ripening the titratable acidity decreased and Balling and pH measurements increased. Although varieties reached maturity on different dates, changes in parameters followed similar curves typical for grapes of the species but occurring over a short period (Johnson and …

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Enzymes In Heloderma Horridum Venom, S. A. Murphy, Bob D. Johnson, D. H. Sifford Jan 1976

Enzymes In Heloderma Horridum Venom, S. A. Murphy, Bob D. Johnson, D. H. Sifford

Journal of the Arkansas Academy of Science

A mixture of venom and saliva from the lizard Heloderma horridum was analyzed for esterase, phosphomonoesterase, phosphodiesterase, 5'nucleotidase, and protease activities. Hydrolysis of N-benzoyl-L-arginine ethyl ester occurred at a pH optimum between pH 8.6 and 9.1 with a maximum activity of 452 units per mg per min. Hydrolysis of ptoluenesulfonyl-L-arginine methyl ester occurred at a pH optimum between pH 8.1 and 8.5 with a maximum of only 36 units per mg per min. One mg of the venom mixture liberated 9.3 μM of p nitrophenol from p-nitrophenyl phosphate per minute at an optimum pH between 8.2 and 8.3. Over a …

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Study Of Ultraviolet-Induces Chromatid And Chromosome Aberrations As A Function Of Dose In G1 Phase Vertebrate Tissue Cultures, Troy V. Orr, H. Gaston Griggs Jan 1976

Study Of Ultraviolet-Induces Chromatid And Chromosome Aberrations As A Function Of Dose In G1 Phase Vertebrate Tissue Cultures, Troy V. Orr, H. Gaston Griggs

Journal of the Arkansas Academy of Science

G1 phase A8 Xenopus laevis (toad) and V79B Cricetulus griseus (hamster) tissue cultures were used to observe the frequency of ultraviolet-induced chromosomal aberrations as a function of dose. When cultures are irradiated with ultraviolet light, visible aberrations are virtually absent until a threshold of approximately 80 ergs mm⁻¹ is reached. Aberrations then occur as a nonlinear function of dose. Chromatid aberrations are by far the most prevalent until doses in excess of 200 ergs mm⁻¹ are administered, at which point chromosome aberrations become common.

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Effect Of Soil Buffer Capacity On Soil Reaction (Ph) Modification And Subsequent Effects On Growth And Nutrient Uptake Of Plantanus Occidentalis L. Seedlings, P. E. Pope, R. B. Vasey Jan 1976

Effect Of Soil Buffer Capacity On Soil Reaction (Ph) Modification And Subsequent Effects On Growth And Nutrient Uptake Of Plantanus Occidentalis L. Seedlings, P. E. Pope, R. B. Vasey

Journal of the Arkansas Academy of Science

The buffer capacity of a soil is a significant factor in determining the longevity of soil reaction (pH) adjustments by aluminum sulfate, Al2(SO4)3, or calcium carbonate, CaCO₂. After 12 weeks the modified pH values of the highly buffered Emory silt loam had changed substantially toward the original pH value of 7.6. Modified pH values for the Groseclose silt loam soil remained essentially unchanged under the same conditions. These differences in soil response to modified soil pH are related to the differences in the percentage of vermiculite chlorite and chlorite in the clay fractions of the two soils. The longevity of …

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Update Of Arkansas Odonata (Anisoptera), John D. Rickett Jan 1976

Update Of Arkansas Odonata (Anisoptera), John D. Rickett

Journal of the Arkansas Academy of Science

Seventy-five species of dragonflies have been reported in Arkansas. The present study provides 43 species; records of the other 32 are drawn from the literature and personal communication with individuals. A new species, Gomphus ozarkensis, described from western Arkansas in 1975 on the basis of minimal data emphasizes the need for extensive work in this area. Opportunities to collect and identify additional species are discussed.

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Scanning Electron Microscope Study Of Brachysclereids Of Pear (Pyrus Communis L.), Clarence B. Sinclair Jan 1976

Scanning Electron Microscope Study Of Brachysclereids Of Pear (Pyrus Communis L.), Clarence B. Sinclair

Journal of the Arkansas Academy of Science

The external surfaces of pear sclereids commonly are illustrated as covered with apertures. This SEAA investigation of the surface features has shown the surface to have few or no apertures. When the primary wall layer was removed the typical ramiform canal system was obvious. This observation confirms the often-ignored fact that the pitapertures of the secondary wall are not continuous with the primary wall. Hence, they do not show on the surfaces of the intact cell.

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Hormone Receptor Site Maturation In The Secondary Sex Organs Of Immature Male And Female Rats, K. J. Thomas Jan 1976

Hormone Receptor Site Maturation In The Secondary Sex Organs Of Immature Male And Female Rats, K. J. Thomas

Journal of the Arkansas Academy of Science

The effect of a combined dose of pregnant mares' serum (PAAS) and human chor ionic gonadotropin (HCG) on male and female rats 2-25 days old was studied. Groups of animals were given injections for three days, then sacrificed on the fourth day. All injections were begun on the 2nd, 7th, 12th, 17th, and 22nd day of life. Ovaries, uteri, seminal vesicles (SV), and ventral prostate (VP) were removed, dissected free of fat, and weighed. Because uterine weight increased earlier than either SV or VP weight, the ability of the uterus to respond to exogenous estradiol and of the SV and …

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Food Sharing Behavior In Primates: Another Species Added, Charles G. Wilson Jan 1976

Food Sharing Behavior In Primates: Another Species Added, Charles G. Wilson

Journal of the Arkansas Academy of Science

Observations of food sharing behavior in golden lion marmosets are reported and three categories of food sharing behavior are proposed for primates: passive, active, and overt.

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Scanning Electron Microscopy Of The Rainbow Trout (Salmo Gairdneri Richardson) Spermatozoon, James H. Fribourgh, Bernard L. Soloff Jan 1976

Scanning Electron Microscopy Of The Rainbow Trout (Salmo Gairdneri Richardson) Spermatozoon, James H. Fribourgh, Bernard L. Soloff

Journal of the Arkansas Academy of Science

The scanning electron microscope was used to determine the morphology of the rainbow trout (Salmo gairdneri Richardson) spermatozoon. The spermatozoon is approximately 32 μm long and consists of a head, mitochondrial collar, and flagellum. The head is elongated and somewhat flattened. It has an antero posterior length of 3.1 μm and a maximum diameter of 1.6 to 2.2 μm. Mean antero-posterior length of the mitochondrial collar is 0.8 μm The collar encircles the flagellum but is separated from it. The flagellum ranges in length from 26 to31 μm and is divided into a principal piece and end piece. Cytoplasmic vesicles …

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Fishes Of The Fourche River In Northcentral Arkansas, Steve M. Bounds, John K. Beadles Jan 1976

Fishes Of The Fourche River In Northcentral Arkansas, Steve M. Bounds, John K. Beadles

Journal of the Arkansas Academy of Science

A survey of the fishes of Fourche River in northcentral Arkansas was made between June 1974 and March 1976. Field collections and literature records revealed that the river system was inhabited by 94 species of fish representing 21 families. The collected fishes represent both the Ozark and the lowland faunal groups. Fourteen species of Etheostoma and four species of Percina were collected. The records of Etheostoma asprigene and Elassoma zonatum represent extensions of the previously known ranges of these species within the state. Noturus gyrinus and Etheostoma histrio were recorded from the Black River system in Arkansas for the first …

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Influence Of Dietary Fats And Carbohydrates On Lipid Metabolism In Male And Female Rats, Marjorie Ellen Fitch Jan 1976

Influence Of Dietary Fats And Carbohydrates On Lipid Metabolism In Male And Female Rats, Marjorie Ellen Fitch

Journal of the Arkansas Academy of Science

Effects of dietary fats and carbohydrates on lipid metabolism in rats were studied. Male and female 4-week-old rats were divided into 8 groups and fed 4 fat-carbohydrate combinations (beef tallow or safflower oil, each with either sucrose or rice starch). After 4 weeks, animals were killed by exsanguination through the abdominal aorta and livers were removed. Plasma and liver cholesterol and phospholipids were determined qualitatively and quantitatively. Liver moisture, protein, and lipid and the fatty acid composition of the total liver lipid were determined quantitatively. Variations in growth, food efficiency, and lipid metabolism, particularly as manifested by the fatty acid …

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Effect Of Estrogen And/Or Supplemental Substrates On Uterine Utilization Of Pyruvate For Lipid Synthesis, Julie W. Harris Jan 1976

Effect Of Estrogen And/Or Supplemental Substrates On Uterine Utilization Of Pyruvate For Lipid Synthesis, Julie W. Harris

Journal of the Arkansas Academy of Science

Precursor incorporation into uterine lipids was examined in vitro after estradiol-17ß administration in immature female rats. The effect of adding supplemental substrates, glucose or gluconate, to the incubation medium on the labeling pattern of pyruvate-3-¹⁴C into uterine lipids was studied. Presence of supplemental substrate in the medium enhanced the incorporation of pyruvate into uterine lipids after two hours of in vivo estrogen treatment. It is suggested that estrogen's acceleration of pyruvate incorporation into lipid may be due to a concomitant effect on glucose metabolism.

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