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Age And Growth Of The Bluegill Lepomis Macrochrius Rafinesque From An Unmanaged Watershed Lake In Northeast Arkansas With Observations On Lake Ecology, Stephen A. Sewell

Journal of the Arkansas Academy of Science

Age and growth data were compiled on 114 bluegill, Lepomis macrochirus Rafinesque, taken from floodwater retarding structure #15 of the Big Creek Watershed project in Craighead and Greene counties of northeast Arkansas. This project was completed in the early 1960's by USDA-SCS. The 73 surface acre lake has not been managed for fish production and has been subjected to unscheduled water level manipulations during dry weather periods. These manipulations have maintained the bluegill population in healthy condition. The oldest bluegill collected were age class IV+. Average condition coefficient K(TL)declined from oldest to youngest individuals (2.96 in age class IV+ - …

Synopsis Of The Nepidae Of Arkansas, George L. Harp

Journal of the Arkansas Academy of Science

No abstract provided.

Further Distributional Records For Arkansas Anisoptera, George L. Harp, John D. Rickett

Journal of the Arkansas Academy of Science

No abstract provided.

Reports Of Albino Birds In Arkansas Since 1968, Earl L. Hanebrink

Journal of the Arkansas Academy of Science

No abstract provided.

Incidence Of Giardia In Arkansas Beaver, Gary A. Heidt, Ann H. Nichols, James J. Daly

Journal of the Arkansas Academy of Science

No abstract provided.

Demonstration Of A Heat-Stable Cyclic Gmp Phosphodiesterase In The Medium Of Physarum Flavicomum, Thomas J. Lynch, Mark S. Ross

Journal of the Arkansas Academy of Science

No abstract provided.

Observations And New Records Of Ferns Naturalizing In Arkansas, James H. Peck, Lance Peacock, William M. Shepherd

Journal of the Arkansas Academy of Science

No abstract provided.

Corticocortical Projections Of A Visually Responsive Area In The Cat Brain, Joseph Mcgrath

Journal of the Arkansas Academy of Science

The Clare-Bishop (CB) area bears the name of the investigators who first (1954) demonstrated a cortical area in the cat brain located along the lateral aspect of the middle suprasylvian gyrus which responded electrophysiologically to both optic nerve and striate cortex (area 17) stimulation. More recent studies of CB or the lateral suprasylvian (LS) area have supported its role in visual and/or oculomotor functions. Silver degeneration methods were undertaken to clarify some of the corticocortical connections of this cortical region. The data accumulated provides a morphological basis in support of the CB area's role in visual and/or oculomotor activities

Role Of Centriolar Matrix And Striated Rootlets In Centriolar Pairing And Orientation During Spermatogenesis In Hydractina Echinata, Maurice G. Kleve

Journal of the Arkansas Academy of Science

Transmission electron microscopy of the spermatogenic stages of the hydroid, Hydractinia echinata, reveals a series of complex structural and positional changes in the centrioles of spermatocytes and spermatids. The newly generated centriolar pairs of spermatocytes form an unusual four-centriole aggregate that persists until cell division. The distal centrioles of this aggregate are shrouded with a very dense matrix that accumulates after centriolar replication. This matrix facilitates the mechanical attachment between distal centrioles and microtubular nucleating satellites, striated rootlets and pericentriolar processes. The association of these accessory structures occurs sequentially and is repeated in spermatocytes and spermatids. An electron dense plaque, …

Ontogenetic Change In Phototactic Responses Of Surface And Cave Populations Of Astyanax Fasciatus (Pisces: Characidae), Aldemaro Romero Jr.

Publications and Research

No abstract provided.

Can Evolution Regress?, Aldemaro Romero Jr.

Publications and Research

No abstract provided.

Morphological Variation Accompanying Cave Evolution In Astyanax Fasciatus (Pisces: Characidae), Aldemaro Romero Jr.

Publications and Research

No abstract provided.

Pirañas Imposibles, Aldemaro Romero Jr.

Publications and Research

No abstract provided.

Twenty-Four-Hour Profiles Of Prolactin And Testosterone In Ram Lambs Exposed To Skeleton Photoperiods Consisting Of Various Light Pulses, B. D. Schanbacher, W. Wu, J. A. Nienaber, G. L. Hahn

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

Individual groups of 6 ram lambs were housed within a controlled environment and exposed to one of 6 photoperiod schedules. Groups I and II received 8 (short day) or 16 (long day) h of continuous light, respectively; Groups III, IV and V were exposed to asymmetrical skeleton photoperiods consisting of a main light period of 7 h followed 9 h later by a light pulse of 1 h, 15 min or 1 min duration, respectively, and Group VI was exposed to a symmetrical skeleton photoperiod consisting of two 1-h light pulses positioned 16 h apart. After 4 weeks of treatment …

The Paul Sears I Know, Rufus H. Moore

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

A compact review of the contributions Paul B. Sears made to science should be part of the record commemorating the 60th anniversary of his presidency of the Nebraska Academy of Sciences. The recollections presented here refer to the multitude of things he has done, primarily as an ecologist. However, the overriding objective is to give a glimpse of the exceptional person his associates have come to know.

Chemical And Radiological Composition Of Air And Ground Water Near The Mineralized Uranium Ore Deposit At Crawford, Nebraska, Arthur W. Struempler

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

Data on chemical composition of ground water collected from the "post-Middle Chadron" Oligocene strata are compared with those from water of the basal Chadron hydrological unit in an area near Crawford, Nebraska, where uranium mineralization is known to occur. Uncorrected Eh values, using a calomel reference electrode, indicated water from the "post-Middle Chadron" Oligocene unit was positive, whereas water from the basal Chadron was negative. The basal Chadron waters contained lower levels of calcium and uranium and higher concentrations of sodium, chloride, sulfate, and total dissolved solids, than did waters from the "post-Middle Chadron" Oligocene zone. Radon and radium concentrations …

Grasshopper Dietary (Orthoptera: Acrididae) From A Nebraska Sand Hills Prairie, Anthony Joern

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

Species-specific selection of host plants by grasshoppers from a Sand Hills grassland in Nebraska is documented by identifying fragments of plants from the foregut. Results from this study are compared with a similar study performed in a mixed-grass pasture near North Platte, Nebraska. On average, a larger number of plants was included in the diet of species at Arapaho Prairie. Differences in specific composition of diets were observed in some cases.

Meet Dr. Bob!, Mary Hanson Pritchard

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

Dr. G(eorge) Robert Coatney was known to many as "Mr. Malaria" because of the leadership he provided for the malaria research and chemotherapy programs during World War II and the Korean War. He is known to many of us affectionately as "Dr. Bob." I first met Dr. Bob early in my parasitological career when he would come to Lincoln to visit his mother and other family members. He often visited Harold W. Manter, too. Although they only brushed shoulders in 1926 as Coatney was leaving and Manter was arriving at the University of Nebraska, the two developed a firm and …

Statistical Services, Jane Speijers, Australian Co-Operation With The National Agricultural Research Project, Thailand.

All other publications

2. TERMS OF REFERENCE

To achieve familiarity with the existing resources for biometrical work within the Department of Agriculture both at Bangkhen and at the regional centres - and to gain an understanding of the present systems whereby biometricians are involved in designing experiments and analysing results. This will involve visits to research stations and discussions with both research directors and scientists.

2.1 To become informed on the planned improvements in biometrical services for regional research centres to be carried out through the Thai/World Bank, National Agricultural Research Project (NARP).

2.2 Against the background of items 2.1 and 2.2 above, …

Barley Agronomy., K. J. Young, B. R. Wylde, B. Raszyk, T. N. Khan

Experimental Summaries - Plant Research

Barley foliar diseases, effect on nitrogen response, 85ES25, 85E24, 85E25, 85MT37, 85ES29, 85MT38, 85E26, 85ES32, 85ES31, 85ES30, 85ES26, 85ES24, 85ES27, 85ES28, 85ES34, 85M27, 85SG27, 85MT42, 85C70,

Low Tillering Cereals, Early Maturity Of Cereals, Cereal Variety And Reduced Branching Lupins., R. Delane, J. Hamblin

Experimental Summaries - Plant Research

Trial 85C62 - growth and water use of low tillering cereals. Trial 85C62 - yield potential of low tillering cereals. Trial WEUNI - response of low tillering breeding lines and standard varieties to sowing rate. Trial 85C45 - effect of flowering date, seeding rate, deep tillage and applied nitrogen on yield of barley. Trial 85C61 - wheat variety x management interaction on sandplain. Trial 85C55 - growth and water use of reduced branching lupins. Trial 85C56 - normal and reduced branching lupins - planting density response.

Structural Comparisons Of Sand Pine Scrubs Of East-Central Florida, Pamela J. Latham

Retrospective Theses and Dissertations

No abstract provided.

Life History Tactics Of The Sailfin Molly (Poecilia Latipinna) In Contrasting Environments, Helen L. Large

Retrospective Theses and Dissertations

Life history tactics of three Central Florida populations of Poecilia latipinna were compared to those predicted by life history selection theory. The three populations were sampled monthly for one year. At each sampling period a series of physicochemical measurements were taken to determine the degree of spatial and temporal environmental heterogeneity within each site. Life history traits determined for each population included size at maturity, size specific fecundity, reproductive effort, and length, weight, and condition of offspring. The population inhabiting the most variable environment was characterized by smaller size at maturity, lower size specific fecundity, lower overall reproductive output, and …

Reproductive Biology Of Thamnophis Sauritus Sackenii (Kennicott) (Reptilia:Serpentes:Colubridae) From East-Central Florida, Steven. Myers

Retrospective Theses and Dissertations

Peninsula ribbon snakes, Thamnophis sauritus sackenii, were collected for 14 months. Of 90 individuals collected and examined, 42 were females, 29 were males, and 19 were neonates. Females had a larger body length than did males. The smallest, sexually mature female had a snout-vent length of 428 mm. Mating occurred from March through May. Parturition occurred from June through October. Vitellogenesis began in spring and ovulation occurred between April and May. Spermatogenic activity occurred from August through December and testes were regressed during other months.

Modification Of Sand Fly Biting Behavior By Leishmania Leads To Increased Parasite Transmission, Raymond Beach, Gabriel Kjilu, Johannis Leeuwenberg

Harold W. Manter Laboratory of Parasitology: Library Materials

To attempt rodent-sand fly-rodent transmission of Leishmania major, laboratory-reared Phlebotomus doboscqi were fed on L. major-infected mice and then refed on uninfected mice 21 days later. Flies which refed either probed 1–2 times and took a full blood meal in less than 10 minutes or probed 3 or more times and took little or no blood during a period of 15 minutes or more. When dissected, 7 of 8 flies which experienced difficulty in obtaining a blood meal had flagellates in their cibaria, an observation supporting the hypothesis that parasites in this part of the alimentary canal modify normal …

Cloning And Characterization Of A Gene (Fadr) Involved In Regulation Of Fatty Acid Metabolism In Escherichia Coli, Concetta C. Dirusso, William D. Nunn

Department of Biochemistry: Faculty Publications

The regulatory gene fadR has been previously characterized by classical genetic means as a diffusible protein which exerts negative control over fatty acid degradation and acetate metabolism. fadR has also been implicated in the regulation of unsaturated fatty acid biosynthesis. To facilitate the identification of the product of the fadR gene and to study the mechanism by which this multifunctional regulatory gene exerts its control, we cloned a segment of DNA containing the fadR gene in the phage vector λL47. Subsequent subcloning of a segment of the chromosomal DNA from the λfadR⁺ phage into various plasmid vectors resulted in …

Nearshore Foodwebs And The Distribution Of Acanthocephalan Parasites In Antarctic Seabirds, Eric P. Hoberg

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Field studies, in the vicinity of Palmer Station during the austral summer of 1982— 1983, yielded an extensive collection of acanthocephalans and other parasites from seabirds, fish and invertebrates. The continuing analysis of this material has resulted in the elucidation of factors that control the occurrence of Corynosoma spp. in Antarctic seabirds. Notably, the host-distribution of Corynosoma spp. suggested that these parasites were being acquired from piscine or possibly amphipod prey, generally in nearshore habitats.

Extrafloral Nectaries On Plants In Communities Without Ants: Hawaii, Kathleen H. Keeler

School of Biological Sciences: Faculty Publications

Since the Hawaiian Islands lack native ants, it was hypothesized that extrafloral nectaries, an ant-related mutualistic trait, should be lacking on native species. Presence of extrafloral nectaries (EFNs) on plants was determined by direct observation and related to vegetation structure and floral composition. Frequency of plants with EFNs was low by all possible comparisons. However, several endemic species had functional EFNs. The hypotheses to explain these anomalies are (1) phylogenetic inertia or (2) mutualism with some other organism than ants.

Proliferation Of Schwann Cells Induced By Axolemmal And Myelin Membranes, Michael Paul Dinneen

Theses and Dissertations

Purified Schwann cells were cultured from neonatal rat sciatic nerve using a modification of the method of Brockes (Brockes, J.P. et al, Brain Res. 165(1979) 105-118). Schwann cells and contaminating fibroblasts were unambiguously identified using fluorescent antibodies to 2'3' cyclic nucleotide 3'-phosphodiesterase and the thy 1.1 antigen respectively. The Schwann cells were quiescent unless challenged with mitogens, They proliferated rapidly in response to the soluable mitogen, cholera toxin, or to membrane fractions from rat CNS or PNS, prepared by the method of DeVries (DeVries, G.H., J Neurochem, 40 (1983) 1709-1717). Mitogenic activity was present in both axolemmal and myelin enriched …

Dissection Of Microphage Activation Using T Cell Hybridoma Derived Lymphokines, William S. Futch Jr.

Theses and Dissertations

Macrophage phenotype/function can be modulated by various T-cell lymphokines (LK). The alteration of macrophage phenotype is a result of LK concentration, duration of exposure, and the level of macrophage activation when obtained from in vivo sources through elicitation by either sterile irritants or immune cellular mechanisms. In order to dissect macrophage activation into discrete signals T cell hybridomas were constructed by fusing HAT sensitive BW5147 cells with nylon-wool purified, con A stimulated T cells. The resulting T cell hybrids were screened for their ability to: (a) protect macrophages from the cytopathic effect of Naegleria; (b) induce class II MHC gene …