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Zooplankton Community Abundance And Diversity In Dardanelle Reservoir, Arkansas, 1981-1990, John D. Rickett, Robert L. Watson Jan 1992

Zooplankton Community Abundance And Diversity In Dardanelle Reservoir, Arkansas, 1981-1990, John D. Rickett, Robert L. Watson

Journal of the Arkansas Academy of Science

Zooplankton samples were collected quarterly from five stations representing the discharge bay and four "control" or "dispersing impact" stations. Rotifers dominated all samples numerically and by the number of taxa. All major groups (Rotifera, Cladocera, Copepoda, and Protozoa) exhibited greatest abundances during the summer. Quarterly variations in abundance and number of taxa were documented. Except for an increase in taxonomic analysis detail between 1981 and 1984 resulting in several more taxa added to the list, no long-term increases, declines or repeating cycles were apparent. Margalef's Richness Index reflected this change and showed a long-term increase with evidence of a 5- …


Distributional Survey Of The Bird-Voiced Treefrog, Hyla Avivoca (Anura: Hylidae), In Arkansas, Stanley E. Trauth Jan 1992

Distributional Survey Of The Bird-Voiced Treefrog, Hyla Avivoca (Anura: Hylidae), In Arkansas, Stanley E. Trauth

Journal of the Arkansas Academy of Science

A field study of the bird-voiced treefrog, Hyla avivoca, was conducted in Arkansas during the summer of 1991. A total of 75 separate sites in 23 counties was visited. Males with their distinctive whistle-like calls were listened for at night at each site. Breeding colonies of Hyla avivoca were found in four of the six major river basins; the study established three new county records. Currently, this species has been documented at 14 sites in 10 counties; in very few situations were the treefrogs locally abundant (voucher specimens deposited in the Arkansas State University Museum of Zoology). Habitat perturbation and …


Effect Of Aerosols On Climate Change, Haiyin Sun, Malay K. Mazumder Jan 1992

Effect Of Aerosols On Climate Change, Haiyin Sun, Malay K. Mazumder

Journal of the Arkansas Academy of Science

A modified two-stream approximation is presented, which includes the effect of solar zenith angle and is applicable to study the effect of aerosols on both regional and global climate changes. More realistic results are derived. A reasonable critical value of 0.8 for aerosol single scattering albedo to determine whether the aerosols will heat or cool the climate is derived


Effects Of Bacterial Lipopolysaccharide On Plasma Corticosterone Concentrations And Body Temperatures Of New Zealand Rabbits (Oryctolagus Cuniculus), Phillip Keith Wilkins, Stanley N. David, Lawrence W. Hinck Jan 1992

Effects Of Bacterial Lipopolysaccharide On Plasma Corticosterone Concentrations And Body Temperatures Of New Zealand Rabbits (Oryctolagus Cuniculus), Phillip Keith Wilkins, Stanley N. David, Lawrence W. Hinck

Journal of the Arkansas Academy of Science

Twelve New Zealand rabbits were injected with Salmonella typhosa endotoxin, 10 ng/kg b.w. ,via an auricular marginal vein and the effects of the pyrogen on the rectal temperatures and plasma corticosterone concentrations of these animals were observed. Our data showed significant increases of the core temperatures from the normal 39.3 +/- 0.18 to 40.9 +/- 0.43 C (p < 0.001). Radioimmunoassay results of the plasma corticosterone levels were 5.76 +/- 3.7 ug/100 ml in the pre-injection blood samples and 9.02 +/- 3.7 ug/100 ml in the plasmas obtained from the animals, one hour after the pyrogen was administered. The increase of corticosterone was significant (p


Synopsis Of The Genus Tropisternus (Coleoptera Hydrophilidae) In Arkansas, George L. Harp Jan 1992

Synopsis Of The Genus Tropisternus (Coleoptera Hydrophilidae) In Arkansas, George L. Harp

Journal of the Arkansas Academy of Science

No abstract provided.


Effect Of Bacterial Lipopolysaccharide-Induced Fever On The Humoral Response Of New Zealand White Rabbits, Lawrence W. Hinck, Stanley N. David Jan 1992

Effect Of Bacterial Lipopolysaccharide-Induced Fever On The Humoral Response Of New Zealand White Rabbits, Lawrence W. Hinck, Stanley N. David

Journal of the Arkansas Academy of Science

No abstract provided.


Erratum: Preparation Of A Series O Fn-Phenylamides Of 5-Bromo-6-Chloronicotinic Acid, Frank L. Setliff, Jody Z. Caldwell Jan 1992

Erratum: Preparation Of A Series O Fn-Phenylamides Of 5-Bromo-6-Chloronicotinic Acid, Frank L. Setliff, Jody Z. Caldwell

Journal of the Arkansas Academy of Science

No abstract provided.


Table Of Contents, Academy Editors Jan 1992

Table Of Contents, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.


In Memoriam: Herman L. Bogan, 1907 - 1992, James H. Fribourgh Jan 1992

In Memoriam: Herman L. Bogan, 1907 - 1992, James H. Fribourgh

Journal of the Arkansas Academy of Science

No abstract provided.


Model For The Co Poisoning Of Hydrodesulfurization Catalysts. Synthesis And Structure Of {Ru(Co)[Pph2sc12h7)]2cl2}.2ch2br2, Mark Draganjac, Thomas B. Rauchfuss, Arnold L. Rheingold Jan 1992

Model For The Co Poisoning Of Hydrodesulfurization Catalysts. Synthesis And Structure Of {Ru(Co)[Pph2sc12h7)]2cl2}.2ch2br2, Mark Draganjac, Thomas B. Rauchfuss, Arnold L. Rheingold

Journal of the Arkansas Academy of Science

The treatment of {Ru[(PPh2SC12H7)]2Cl2} with CO at ambient conditions results, after work up, in the isolation of the monocarbonylated species {Ru(CO)[(PPh2SC12H7)]2Cl2}, I. Crystals of I(C51H38Br4Cl20P2RuS2; F.W. = 1284.6) are triclinic; Ppa= 11.587(3), b = 13.010(4), c = 17.309(4) A, a = 93.32(2)°, p = 106.51(2)°, y = 91.29(2)°; Z= 2; V=2495(1) A';d^,. = 1.709 gem 1 X(MoKa) = 0.71073 A, = 37.7 cm 1 ;R =0.0748; Rw = 0.0714 for 4141 unique reflections. The geometry about the Ru(II) center is pseudooctahedral, with the phosphine ligands in the trans configuration. The Ru-S bond distance is 2.425(3) A.


Documented Aids Cases As The Basis For Projections Of Adolescence Hiv Infections In The Us, R. Ron Goforth, S. A. Goforth Jan 1992

Documented Aids Cases As The Basis For Projections Of Adolescence Hiv Infections In The Us, R. Ron Goforth, S. A. Goforth

Journal of the Arkansas Academy of Science

Twenty percent of AIDS cases in the U.S. occur in individuals in the age range 20 to 29. The mean incubation time, the time from infection to the onset of AIDS, is in the order of 8 years. Therefore, most of these AIDS cases represent HIV infections that occurred during mid- to late-adolescence. About 800 officially reported cases in the age group 13 to 19 have occurred in the U.S. This low occurrence of AIDS should not be a source of complacency in assessing the need to provide education and behavioral alternatives to this age group. As the predominate mode …


Schroedinger Equation With Spherically Averaged Potentials, C. A. Hughes Jan 1992

Schroedinger Equation With Spherically Averaged Potentials, C. A. Hughes

Journal of the Arkansas Academy of Science

Using a method adapted from few—body hyperspherical techniques, an approach to the solution of the Schroedinger equation with nonspherical potentials is discussed. The method is to spherically average the potential over spherical angles and then solve the resulting set of coupled differential equations. A discussion of how this method is applied to the Stark effect is presented.


Measuring Shrubland Vegetational Structure Using Avian Habitats As An Example, Douglas A. James Jan 1992

Measuring Shrubland Vegetational Structure Using Avian Habitats As An Example, Douglas A. James

Journal of the Arkansas Academy of Science

Vegetational sampling of avian habitats stresses the use of methods primarily designed for forest birds. This paper describes a technique for sampling vegetational structure in uneven patchy habitats such as shrublands. Using the method, avian habitats in old field shrublands of northwestern Arkansas were analyzed.


Long-Term White-Tailed Deer Harvest Trends For The Southcentral United States, Richard A. Kluender, Philip A. Tappe, Michael E. Cartwright Jan 1992

Long-Term White-Tailed Deer Harvest Trends For The Southcentral United States, Richard A. Kluender, Philip A. Tappe, Michael E. Cartwright

Journal of the Arkansas Academy of Science

White-tailed deer herd size across the southcentral states continues to increase. Concurrent with this increase has come a total harvest level increase for most states. Southcentral states have increased bag limits on antlerless deer to insure that herd health is maintained as herd sizes approach total carrying capacity. Harvest growth rates, however, show irregularities from year to year. The cyclic pattern of harvest (and population) growth rate is of shorter duration than would be expected in a large ungulate population. An exogenous influence is suspected. Cyclic patterns in harvest growth rates move opposite the growth rate of epizootic hemorrhagic disease …


Phytoplankton Community Abundance And Diversity In Dardanelle Reservoir, Arkansas, 1981-1990, John D. Rickett, Robert L. Watson Jan 1992

Phytoplankton Community Abundance And Diversity In Dardanelle Reservoir, Arkansas, 1981-1990, John D. Rickett, Robert L. Watson

Journal of the Arkansas Academy of Science

Phytoplankton samples were collected quarterly from 1981-1990 at five stations representing discharge water from Arkansas Nuclear One, a nuclear generating station, and four "control" or "dispersal evaluation" stations. Seventy-five taxa representing five divisions were identified and enumerated. Community structure was evaluated using abundances, number of taxa, and Margalef's Richness, Shannon's Heterogeneity and Pielou's Evenness indices. No long-term trends were identified, but the beginning of cyclic variations, with a 7-year periodicity, in abundance, number of taxa, and Shannon's and Pielou's indices were apparent. Margalef's index values were constant during most of the study period. For all samples, t-tests and Mann-Whitney U …


Reproduction In The Western Mud Snake, Farancia Abacura Reinwardtii (Serpentes: Colubridae), In Arkansas, John W. Robinette, Stanley E. Trauth Jan 1992

Reproduction In The Western Mud Snake, Farancia Abacura Reinwardtii (Serpentes: Colubridae), In Arkansas, John W. Robinette, Stanley E. Trauth

Journal of the Arkansas Academy of Science

The reproductive cycle of Farancia abacura reinwardtii was studied using samples of snakes collected throughout Arkansas from 1985 to 1991 ;museum specimens were also examined. The right testis of 22 males was examined by light microscopy. Histological analysis of the testis indicated a postnuptial spermatogenic cycle. Testicular recrudescence begins in late May with sperm production peaking in late summer; sperm over winter in the ductus deferens. Ovarian follicles of 22 females were measured and counted; two follicular sizes were noted. In those undergoing primary vitellogenesis, a maximum size of 6.5 mm was reached; those exhibiting secondary vitellogenesis ranged in size …


Development Of Organic Mud Mounds In A Mixed Carbonate-Siliciclastic Depositional Environment, John M. Ryan, Doy L. Zachry Jan 1992

Development Of Organic Mud Mounds In A Mixed Carbonate-Siliciclastic Depositional Environment, John M. Ryan, Doy L. Zachry

Journal of the Arkansas Academy of Science

Organic carbonate mud mounds in the Prairie Grove Member of the Hale Formation developed on a shallow shelf swept by competent tidal currents. The mounds were stabilized by crustose red algae and fostered a sheltered setting where phylloid algae and marine invertebrates could thrive. The mounds supplied skeletal sediment locally to the intermound areas as well as regionally along the stable platform. This sediment mixed with quartz sand to form a major mixed carbonate-siliciclastic system in northwestern Arkansas.


4-Substituted Anilides Of 2,6- And 5,6- Dichlorolicotinic Acid. Potential Agricultural Agents, Frank L. Setliff, Nikhil G. Soman Jan 1992

4-Substituted Anilides Of 2,6- And 5,6- Dichlorolicotinic Acid. Potential Agricultural Agents, Frank L. Setliff, Nikhil G. Soman

Journal of the Arkansas Academy of Science

A series of 4-substituted anilides of 2,6- and 5,6 dichloronicotinic acid were prepared. The acids were first converted to their acid chlorides, which were in turn treated with the appropriate 4-substituted aniline in chloroform. A total of 16 anilides was thus prepared, and their structures confirmed. These compounds were prepared for testing as possible herbicidal, pesticidal or fungicidal agents


Hammett Correlations In The 1H Nmr Spectra Of Some N-Arlydihalonicotinamides, Frank L. Setliff, Nikhil G. Soman, Jody Z. Caldwell, Debra L. Rogers Jan 1992

Hammett Correlations In The 1H Nmr Spectra Of Some N-Arlydihalonicotinamides, Frank L. Setliff, Nikhil G. Soman, Jody Z. Caldwell, Debra L. Rogers

Journal of the Arkansas Academy of Science

Excellent linear correlations of amide proton chemical shifts (Snh) (in DMSO-d6 ) with Hammett substituent constants (5) for a series of 4-substituted anilides of four dihalonicotinic acid systems were observed. Dihalonicotinanilides with chlorine in the pyridine 2 - position exhibited a more positive slope in a Hammett plot of S^H vs - aR- where R is the substituent in the 4 position of the benzene ring. This observation is explained in terms of the inductive effect of chlorine which results in a slightly more acidic amide proton, which in turn causes an enhanced hydrogen bonding tendency to solvent. Four disubstituted …


Application Of Stable Operating Criterion To Grating Tuned Strong External Feedback Semiconductor Lasers, Haiyin Sun, Malay K. Mazumder Jan 1992

Application Of Stable Operating Criterion To Grating Tuned Strong External Feedback Semiconductor Lasers, Haiyin Sun, Malay K. Mazumder

Journal of the Arkansas Academy of Science

Stability analysis is done by applying criterion dnQ((o)/cfco>0 for grating tuned strong external feedback semiconductor lasers. The resulting stable and unstable operating ranges agree well with experiment results.


Status Of The Ozark Hellbender, Cryptobranchus Bishopi (Urodela: Cryptobranchidae), In The Spring River, Fulton County, Arkansas, Stanley E. Trauth, J. D. Wilhide, Patrick Daniel Jan 1992

Status Of The Ozark Hellbender, Cryptobranchus Bishopi (Urodela: Cryptobranchidae), In The Spring River, Fulton County, Arkansas, Stanley E. Trauth, J. D. Wilhide, Patrick Daniel

Journal of the Arkansas Academy of Science

We conducted a tag and release study of the Ozark hellbender along a 26 km stretch of the Spring River from mid-July through mid-November, 1991, to determine current population levels. Salamanders were collected by hand with the aid of scuba diving equipment. Thirteen visits(36 dive hrs.) to10 selected access sites yielded 20 animals. Compared to previously published data of the early 1980's which indicated large, striving populations of C. bishopi(in some cases, > 300 individuals) in the Spring River, our study found perilously low numbers of salamanders. This drastic decline may be attributed to over collection of specimens for scientific or …


Assessment Of Timber Resource Values In Arkansas, Richard A. Williams, Richard A. Kluender Jan 1992

Assessment Of Timber Resource Values In Arkansas, Richard A. Williams, Richard A. Kluender

Journal of the Arkansas Academy of Science

The Arkansas forest lands have long been and will continue to be an important contributor to the state's economy. Today, Arkansas forests cover 52 percent of the land area (Hines and Vissage, 1988). These forests are classified by physiographic characteristics into four timber regions. The timber removed from forested lands provides direct and indirect employment for approximately 40,000 people within the Arkansas manufacturing sector (Kluender and Willett, 1989). This paper describes county and region level information, identifies standing timber volumes, net annual timber growth, net annual timber removals, and associated dollar values. Timber stand data are used to determine areas …


Biological Vectors For The Dispersal Of Colletotrichum Gloeosporioides, X. B. Yang, D. O. Tebeest, E. L. Moore Jan 1992

Biological Vectors For The Dispersal Of Colletotrichum Gloeosporioides, X. B. Yang, D. O. Tebeest, E. L. Moore

Journal of the Arkansas Academy of Science

Green treefrogs (Hyla cinerea) and grasshoppers (Melanoplus differentialis and Conocephalus fasciatus) commonly observed in Arkansas rice fields, are dispersal vectors for Colletotrichum gloeosporioides f. sp. aeschynomens, a causal agent of anthracnose of northern jointvetch. Treefrogs and grasshoppers captured from rice or soybean fields with diseased northern jointvetch were placed in containers in contact with healthy northern jointvetch plants. An average of 90% of northern jointvetch plants was infected by the pathogen with up to 10 lesions per plant using treefrog vectors. Experiments were done in the greenhouse on frog dispersal by monitoring disease development from a point source in closed …


Distribution Of The Southern Red-Backed Salamander, Plethodon Serratus (Caudata: Plethodontidae) In The Ouachita Mountain Region Of Arkansas, M. Doug Fletcher, Betty G. Cochran, Stanley E. Trauth, David A. Saugey Jan 1992

Distribution Of The Southern Red-Backed Salamander, Plethodon Serratus (Caudata: Plethodontidae) In The Ouachita Mountain Region Of Arkansas, M. Doug Fletcher, Betty G. Cochran, Stanley E. Trauth, David A. Saugey

Journal of the Arkansas Academy of Science

No abstract provided.


Techniques For Efficiency Calibration Of Photon Detectors For X-Rays And Low Energy Gamma Rays, Rahul Mehta Jan 1992

Techniques For Efficiency Calibration Of Photon Detectors For X-Rays And Low Energy Gamma Rays, Rahul Mehta

Journal of the Arkansas Academy of Science

No abstract provided.


Sequential Occupation By Red-Cockaded Woodpeckers And Red-Bellied Woodpeckers In The Ouachita National Forest, Joseph C. Neal, Warren G. Montague, Douglas A. James Jan 1992

Sequential Occupation By Red-Cockaded Woodpeckers And Red-Bellied Woodpeckers In The Ouachita National Forest, Joseph C. Neal, Warren G. Montague, Douglas A. James

Journal of the Arkansas Academy of Science

No abstract provided.


Maternity Colony Of Gray Bats In A Non-Cave Site, Lorraine Timmerman, V. Rick Mcdaniel Jan 1992

Maternity Colony Of Gray Bats In A Non-Cave Site, Lorraine Timmerman, V. Rick Mcdaniel

Journal of the Arkansas Academy of Science

No abstract provided.


New Records Of Vertebrates In Southwestern Arkansas, C. Renn Tumlison, Mark R. Karnes, Mark E. Clark Jan 1992

New Records Of Vertebrates In Southwestern Arkansas, C. Renn Tumlison, Mark R. Karnes, Mark E. Clark

Journal of the Arkansas Academy of Science

No abstract provided.


Age Specific Analysis Of Food Habits For Arkansas Raccoons (Procyon Lotor), J. D. Wilhide, V. Rick Mcdaniel, C. Renn Tumlison Jan 1992

Age Specific Analysis Of Food Habits For Arkansas Raccoons (Procyon Lotor), J. D. Wilhide, V. Rick Mcdaniel, C. Renn Tumlison

Journal of the Arkansas Academy of Science

No abstract provided.


Development Of A Variable Wavelength Flame Infrared Emission Gas Chromatography Detector, Weiqun Zhang, M. Keith Hudson, Mokhtar Mofidi Jan 1992

Development Of A Variable Wavelength Flame Infrared Emission Gas Chromatography Detector, Weiqun Zhang, M. Keith Hudson, Mokhtar Mofidi

Journal of the Arkansas Academy of Science

No abstract provided.