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Photosynthetic Efficiency Of Drought-Induced Leaves In Neviusia Alabamensis, Jennifer Martsolf, Robert D. Wright Jan 1991

Photosynthetic Efficiency Of Drought-Induced Leaves In Neviusia Alabamensis, Jennifer Martsolf, Robert D. Wright

Journal of the Arkansas Academy of Science

Plants in one stand of Neviusia alabamensis Gray (Rosaceae), a rare shrub, became drought deciduous in July, 1990, and grew new leaves following rains in August. In September the photosynthetic efficiency of the new leaves was compared with that of old leaves in another stand of the same population. Although leaf area from regrowth was much less than old leaf area retained, photosynthetic efficiency in new leaves was about 3 times higher than in old leaves. This response is discussed in terms of compensation for drought-induced loss of leaves.

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Past And Present Distribution Of The Red-Cockaded Woodpecker Picoides Borealis And Its Habitat In The Ouachita Mountains, Arkansas, Joseph C. Neal, Warren G. Montague Jan 1991

Past And Present Distribution Of The Red-Cockaded Woodpecker Picoides Borealis And Its Habitat In The Ouachita Mountains, Arkansas, Joseph C. Neal, Warren G. Montague

Journal of the Arkansas Academy of Science

Within the past 15 years, at least 41 and probably more active cavity tree clusters (or colonies) of Red cockaded Woodpeckers (Picoides borealis) have existed in remnant, mature shortleaf pine (Pinus echinata) woodlands in the Ouachita Mountains of Arkansas. These clusters were located on both private timberlands and in the Ouachita National Forest. Fewer than half of this number were still active in early 1991, and none remained on private timberlands. The species is presently restricted to the xeric, western margins of the Ouachitas in Scott and Polk counties within the confines of the Ouachita National Forest where it receives …

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An Analysis Of Stomach Contents Of The Ouachita Madtom In Three Streams Of The Upper Saline River Drainage, Arkansas, Tim M. Patton, Mark L. Zornes Jan 1991

An Analysis Of Stomach Contents Of The Ouachita Madtom In Three Streams Of The Upper Saline River Drainage, Arkansas, Tim M. Patton, Mark L. Zornes

Journal of the Arkansas Academy of Science

A study was conducted to identify typical foods eaten by the Ouachita madtom (Noturus lachneri), an endemic ictalurid of central Arkansas, and to compare these foods to the invertebrate community. Fish and invertebrate samples were collected in August and October, 1990, from a pool and adjacent riffle habitat in each of 3 streams in the upper Saline River drainage. Kick-net and electrofishing samples were collected at each site and the invertebrate organisms were identified to the lowest possible taxa. Stomachs from the N. lachneri specimens were removed and the contents were identified to order. Frequency of occurrence of each taxon …

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Groundwater Hydrology Of A Population Of Lindera Melissifolia In Arkansas, J. Dainette Priest, Robert D. Wright Jan 1991

Groundwater Hydrology Of A Population Of Lindera Melissifolia In Arkansas, J. Dainette Priest, Robert D. Wright

Journal of the Arkansas Academy of Science

Groundwater hydrology was monitored from October through August in and around a bottomland forest pond containing Lindera melissifolia, pondberry. The study site exhibited a series of low ancient dunes and depressions, with seasonal ponds in the depressions. Ponds showed no surface inlets or outlets. Shallow wells were made and soil cores removed along a transect from the top of one dune across the pond to a lower dune. Piezometers were installed in the wells and groundwater levels monitored. Soil core samples were analyzed to determine particle size distribution at soil profile positions selected during field analysis. It was shown that …

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Distribution, Scutellation, And Reproduction In The Queen Snake, Regina Septemvittata (Serpentes: Colubridae), From Arkansas, Stanley E. Trauth Jan 1991

Distribution, Scutellation, And Reproduction In The Queen Snake, Regina Septemvittata (Serpentes: Colubridae), From Arkansas, Stanley E. Trauth

Journal of the Arkansas Academy of Science

The queen snake, Regina septemvittata, has a disjunct portion of its distribution in Arkansas. This rare, crayfish-eating species is best known from only a few isolated populations from several major streams that flow out of the Boston Mountains of the Ozark Plateau. A field study of this species was conducted during the summer of 1990, and only 4 specimens were documented. Gravid females were collected in July; sperm production was also noted in July. Parturition presumably takes place in August or early September. This species may qualify as threatened or endangered in Arkansas.

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Survey And Annotated Checklist Of The Later Summer Flora Of The Moist Soil Units At Holla Bend National Wildlife Refuge, Stephen A. Walker, George P. Johnson Jan 1991

Survey And Annotated Checklist Of The Later Summer Flora Of The Moist Soil Units At Holla Bend National Wildlife Refuge, Stephen A. Walker, George P. Johnson

Journal of the Arkansas Academy of Science

We conducted a floristic survey of 22 moist soil units at Holla Bend National Wildlife Refuge during September and October of 1990. The moist soil units range in size from 0.4 to 9.7 ha and are depressions manipulated to provide food and shelter for waterfowl. In total, 60 taxa representing 24 families and 42 genera were identified and are compiled into an annotated checklist. The flora was dominated by the following families and genera in decreasing order of importance: Asteraceae (Xanthium), Polygonaceae (Polygonum), and Amaranthaceae (Amaranthus). The Poaceae and the Cyperaceae were well represented, but were of lesser importance. Twenty-three …

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Identifying Colibri Hummingbirds Occurring In Arkansas Using Indirect Measurements, Douglas A. James Jan 1991

Identifying Colibri Hummingbirds Occurring In Arkansas Using Indirect Measurements, Douglas A. James

Journal of the Arkansas Academy of Science

No abstract provided.

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Range Extension Of The Endangered Gray Bat, Myotis Grisescens, Into The Arkansas River Valley, Thomas A. Nelson, David A. Saugey, Lee E. Carolan Jan 1991

Range Extension Of The Endangered Gray Bat, Myotis Grisescens, Into The Arkansas River Valley, Thomas A. Nelson, David A. Saugey, Lee E. Carolan

Journal of the Arkansas Academy of Science

No abstract provided.

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Aggressive Interactions Between Male Cotton Mice (Peromyscus Gossypinus) And Male Texas Mice (P. Attwateri), John A. Peppers, David W. Royal, Gary A. Heidt Jan 1991

Aggressive Interactions Between Male Cotton Mice (Peromyscus Gossypinus) And Male Texas Mice (P. Attwateri), John A. Peppers, David W. Royal, Gary A. Heidt

Journal of the Arkansas Academy of Science

No abstract provided.

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Posterior Maxillary Fangs Of The Flathead Snake, Tantilla Gracillis (Serpentes: Colubridae), Using Scanning Electron Microscopy, Stanley E. Trauth Jan 1991

Posterior Maxillary Fangs Of The Flathead Snake, Tantilla Gracillis (Serpentes: Colubridae), Using Scanning Electron Microscopy, Stanley E. Trauth

Journal of the Arkansas Academy of Science

No abstract provided.

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Cyclic, Multi-Stage Biological Process For Wastewater Treatment, James C. Young Dec 1990

Cyclic, Multi-Stage Biological Process For Wastewater Treatment, James C. Young

Patents Granted

A method is described for anaerobic biological waste treatment in multiple stages where a relatively high strength wastewater is introduced into a first biological reactor to produce an effluent of reduced strength. The effluent is passed into a second biological reactor for reaction to take place. The passage of the effluent into the second biological reactor is continued until the biological solids in the second reactor enter into a negative growth phase. It becomes relatively stable, where the flow of waste through the reactors is reversed by terminating introduction of the waste into the first reactor and passing the same …

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Determination Of The Suitability Of Arkansas River Water For Municipal, Industrial And Agricultural Use: Volume 3 Treatability Study, Steven M. Jones, Steven G. Burghart, James W. Moore May 1990

Determination Of The Suitability Of Arkansas River Water For Municipal, Industrial And Agricultural Use: Volume 3 Treatability Study, Steven M. Jones, Steven G. Burghart, James W. Moore

Arkansas Water Resources Center Technical Reports

Volume III of the overall report for the project to determine the suitability of the Arkansas River for municipal, agricultural and industrial water supplies contains the treatability data. These data include the results of the granular activated carbon, ozonation and packed tower aeration studies. The research project was conducted under contract with the Arkansas Soil and Water Conservation Commission. Funding was provided by the Corps of Engineers, the Environmental Protection Agency, the City of Little Rock, Rockefeller Foundation and the Ozark Society. Additionally, the U.S. Geological Survey contributed financially by matching the cost of sample collection. The City of Little …

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Beaver Lake Water Quality Monitoring Plan, Kenneth W. Carter, George Losak, Kenneth Steele, Joel Cahoon, Dwayne Edwards, Tommy C. Daniel, Richard Meyer, Dee Mitchell Feb 1990

Beaver Lake Water Quality Monitoring Plan, Kenneth W. Carter, George Losak, Kenneth Steele, Joel Cahoon, Dwayne Edwards, Tommy C. Daniel, Richard Meyer, Dee Mitchell

Arkansas Water Resources Center Technical Reports

The Beaver Lake basin is located in Northwest Arkansas, and includes portions of Washington, Madison, Benton, Carroll and Franklin counties. The White River is the :major tributary to Beaver lake, with minor tributaries including the Middle and West Forks of the Whi 1:e River, Richland Creek and War Eagle Creek. The basin encompassing 1,186 square miles of drainage area provides a usable storage capacity of 1.22 :million acre-feet, 300,000 of which are designated as flood control, the remainder is utilized for power generation and water supply. Beaver Lake is the water source for both the Beaver and Carroll County Water …

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Analysis Of The Fall And Winter Diet Of The Bobcat In Eastern Arkansas, C. Renn Tumlison, V. Rick Mcdaniel Jan 1990

Analysis Of The Fall And Winter Diet Of The Bobcat In Eastern Arkansas, C. Renn Tumlison, V. Rick Mcdaniel

Journal of the Arkansas Academy of Science

Food habits of the bobcat (Felis rufus) in eastern Arkansas were examined based on stomach contents of 148 specimens. Rabbits (Sylvilagus floridanus and S. aquaticus) were the primary food source for males, females, and kittens. Rice rats (Oryzomys palustris), nutria (Myocastor coypus), and several species of waterfowl are first reported as food of bobcats in Arkansas. Cotton rats (Sigmodon hispidus) and muskrats (Ondatra zibethica) were more common in bobcat diets in eastern versus western Arkansas. Adult males did not use smaller prey but this food source was common, in kittens; females were intermediate in their use of smaller prey.

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Conformational And Circular Dichroism Studies On N-Acetyl-L-Prolyl-D-Alanyl-Methylamide, S. Ramaprasad Jan 1990

Conformational And Circular Dichroism Studies On N-Acetyl-L-Prolyl-D-Alanyl-Methylamide, S. Ramaprasad

Journal of the Arkansas Academy of Science

The compact ordered conformations of the molecule N-Acteyl-L-Prolyl-D-Alanyl-Methylamide have been studied by semiempirical energy calculations in vacuum and circular dichroism (CD) in solution. The presence of ordered structure has been observed in hydrogen bond promoting solvents like trifluoroethanol by CD studies. In hydrogen bond breaking solvents, like trifluoroacetic acid (TFA), significant fraction of the ordered conformers probably assume extended conformation without intramolecular hydrogen bonds and perhaps are in equilibrium with the fraction of compact ordered structures. The trend observed in going from nonpolar to polar solvent is also compatible with the previous NMR studies in solution. The semiempirical energy calculations …

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74th Annual Meeting, 1990. Secretary's Report And Financial Statement, Academy Editors Jan 1990

74th Annual Meeting, 1990. Secretary's Report And Financial Statement, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.

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Rotational Symmetries Of Nuclear States: Spin Determinations In Advanced Laboratory, Wilfred J. Braithwaite Jan 1990

Rotational Symmetries Of Nuclear States: Spin Determinations In Advanced Laboratory, Wilfred J. Braithwaite

Journal of the Arkansas Academy of Science

An advanced laboratory experiment is described which shows the connection between the rotational symmetries of nuclear states and the assignments of spins to discrete nuclear states. Standard angular correlation methods were used to study the two sequential gamma ray transitions in each ⁶⁰Ni nucleus, populated by unobserved beta decays from a weak radioactive ⁶⁰Co source. The chosen electronics and detectors were inexpensive and easy to operate. This experiment was extended to introduce students to real-world data acquisition, using finite-geometry detectors, which resulted in enormously larger coincident data rates.

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Proceedings Of The Arkansas Academy Of Science - Volume 44 1990, Academy Editors Jan 1990

Proceedings Of The Arkansas Academy Of Science - Volume 44 1990, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.

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Aquatic Macroinvertebrates Of The St. Francis Sunken Lands In Northeast Arkansas, Betty G. Cochran, George L. Harp Jan 1990

Aquatic Macroinvertebrates Of The St. Francis Sunken Lands In Northeast Arkansas, Betty G. Cochran, George L. Harp

Journal of the Arkansas Academy of Science

The primary objective of this study was to survey the aquatic macroinvertebrate diversity of the St. Francis Sunken Lands in northeast Arkansas. Secondary objectives were a determination of their relative abundance and distributional and seasonal patterns. Sixty semi-annual collections were made from 30 stations by sampling each station 2 times for 1 ½ man-hours with a Turtox Indestructible™ dip net. Totals of 243 taxa and 13,952 organisms were recorded for the sample period (August 1987 - July 1988). Each station was assigned to 1 of 4 associations, distinguished by distinct physical factors within the river channels and the immediate watershed. …

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Hematozoa Of Common Grackles (Quiscalus Quiscula Versicolor, Vieillot) In Central Arkansas, Arthur A. Johnson Jan 1990

Hematozoa Of Common Grackles (Quiscalus Quiscula Versicolor, Vieillot) In Central Arkansas, Arthur A. Johnson

Journal of the Arkansas Academy of Science

During the years 1977-84, 118 bronzed grackles, Quiscalus quiscula versicolor, Vieillot, of 132 examined were found infected with hematozoa. The eight species of symbionts collected from the infected birds included two microfilarial species (Chandlerella quiscali and Eufilaria hibleri), five apicomplexans (Haemoproteus quiscali, Leucocytozoon fringillinarum, Plasmodium matutinum, P. vaughani, P. sp.) and a flagellate (Trypanosoma ontarioensis). P. matutinum and T. ontarioensis represent new host records and all the protozoans represent new locality records. Comparisons are made of symbiont prevalance and diversity as this relates to seasons of the year, sex and age of the host. Comparisons are also made with previous …

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Image Enhancement Of Faded Historic Documents, Robert Crisp Jr., Barry C. Wells Jan 1990

Image Enhancement Of Faded Historic Documents, Robert Crisp Jr., Barry C. Wells

Journal of the Arkansas Academy of Science

No abstract provided.

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74th Annual Meeting, 1990. Program, Academy Editors Jan 1990

74th Annual Meeting, 1990. Program, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.

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Preliminary Study To Determine The Effect Of Microwaves On Green Wood, Rudolph J. Eichenberger Jan 1990

Preliminary Study To Determine The Effect Of Microwaves On Green Wood, Rudolph J. Eichenberger

Journal of the Arkansas Academy of Science

A preliminary study was done to determine the moisture content of green wood by treating the wood with microwaves in an oven for various times between 1 and 4 minutes. The temperature of the wood was measured immediately following the radiation with a probe interfaced to a microcomputer and with a mercury-in-glass thermometer. Temperature probes were inserted into the wood samples. Actual moisture content of the wood was determined by weighing the samples before and after drying. Half of the samples exhibited a directly proportional relationship between moisture content and temperature after microwaving. The linear relationship was not generalizable to …

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Time Course Of Photoreactivation Of Uv Induced Damage In G1 Phase Xenopus Cells That Leads To Chromosome Breaks Observable By Premature Chromosome Condensation, Robert Wright, Stephen Ruble, H. Gaston Griggs Jan 1990

Time Course Of Photoreactivation Of Uv Induced Damage In G1 Phase Xenopus Cells That Leads To Chromosome Breaks Observable By Premature Chromosome Condensation, Robert Wright, Stephen Ruble, H. Gaston Griggs

Journal of the Arkansas Academy of Science

No abstract provided.

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Correction: Reproductive Characteristics Of South Florida Sternotherus Odoratus And Kinosternon Baurii (Testudines: Kinosternidae), Walter E. Meshaka Jr. Jan 1990

Correction: Reproductive Characteristics Of South Florida Sternotherus Odoratus And Kinosternon Baurii (Testudines: Kinosternidae), Walter E. Meshaka Jr.

Journal of the Arkansas Academy of Science

No abstract provided.

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Publication Policies And Suggestions For Authors, Academy Editors Jan 1990

Publication Policies And Suggestions For Authors, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.

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Mermithid Nematodes: Sem Observations Comparing Hexamethyldisilazane And Critical Point Drying Methods, William R. Bowen, Christopher C. Hemann, Arthur A. Johnson, Barry H. Good Jan 1990

Mermithid Nematodes: Sem Observations Comparing Hexamethyldisilazane And Critical Point Drying Methods, William R. Bowen, Christopher C. Hemann, Arthur A. Johnson, Barry H. Good

Journal of the Arkansas Academy of Science

Morphological features of mermithid nematodes (Mermithidae) were studied with scanning electron microscopy, using hexamethyldisilazane-air drying in comparison with critical point drying via liquid carbon dioxide. Although general morphologic preservation of both HMDS-dried and CP-dried specimens was similar, structural features of the complex cuticle and internal organization were more easily resolved at higher magnifications in the HMDS-dried nematodes. These features include the superficial cuticular annulations, the fibrillar inner cuticle and peg-like microtrabeculae. The previously undescribed microtrabeculae are of special interest since they may facilitate an interaction of the mermithid (and perhaps nameatodes in general) musculature with its body wall that, at …

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Principles And Clinical Applications Of Magnetic Resonance, Rao P. Gullapalli, Teresa T. Evans, Roger M. Hawk Jan 1990

Principles And Clinical Applications Of Magnetic Resonance, Rao P. Gullapalli, Teresa T. Evans, Roger M. Hawk

Journal of the Arkansas Academy of Science

A review is presented which covers the basic theory of nuclear magnetic resonance (NMR) with regard to angular momentum, magnetic moments, and the classical mechanical description of the NMR experiment. Longitudinal (T,) and Transverse (T2) relaxation times are defined as well as the basic pulse sequences used for their measurement. In particular, the 180°-t-90° and the Hahn Spin Echo pulse sequences are described in detail. Basic Magnetic Resonance Imaging (MRI) theory is discussed with regard to slice selection, frequency encoding, and phase encoding to define the imaged volume element. The equations defining the amount of Tt , T2 , and …

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Comparison Of Methods For Purification Of Dna From Rice, Theresa L. Hines, Neela R. Patel, Daoud Abu-Diab, Michael Sikes, Alvan K. Karlin Jan 1990

Comparison Of Methods For Purification Of Dna From Rice, Theresa L. Hines, Neela R. Patel, Daoud Abu-Diab, Michael Sikes, Alvan K. Karlin

Journal of the Arkansas Academy of Science

Three techniques were employed to purify genomic DNA from deomstic rice (Oryza sativa L). Following extraction, the DNA was electrophoresed through agarose to determine its integrity. We determined that spooling yielded better quality, through lower quantity DNA than either of the other two techniques.

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Fecundity Of Male White-Tailed Deer On Holla Bend National Wildlife Refuge, Thomas A. Nelson, Michael W. Johnson Jan 1990

Fecundity Of Male White-Tailed Deer On Holla Bend National Wildlife Refuge, Thomas A. Nelson, Michael W. Johnson

Journal of the Arkansas Academy of Science

Male reproductive tracts were collected from 57 white-tailed deer (Odocoileus virginianus) harvested on Holla Bend National Wildlife Refuge during the 1988 and 1989 archery deer seasons. Organ weights and total numbers of spermatozoa present were determined for both testes and epididymides. Among yearling and adult males, the mean weights of testes and epididymides peaked during November and decreased through the end of the collection period in mid-December. Total number of spermatozoa in the tract increased through October, peaked during the last half of November, and decreased through mid- December. No significant difference was found between the mean number of spermatozoa …

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