THE PRAIRIE NATURALIST Volume 13, Number 2. June 1981

HERPETOFAUNA OF MORMON ISLAND PRESERVE, HALL COUNTY, NEBRASKA ▪ S. M. Jones, R. E. Ballinger and J. W Nietfeldt COYOTE USE OF PLAYAS IN THE TEXAS HIGH PLAINS ▪ R. W. Whiteside and F. S. Guthery NEW RECORD OF THE LEAST WEASEL IN WYOMING ▪ M. R. Stromberg, D. E. Biggens and M. Bidwell STATUS OF AMERICAN WOODCOCK IN NEBRASKA WITH NOTES ON A RECENT BREEDING RECORD ▪ G. R. Lingle WINTER FOODS OF THE PINE GROSBEAK IN EASTERN NORTH DAKOTA ▪ R. C. Reigh SEASONAL VARIATION IN HOME RANGE OF A FEMALE BADGER (Taxidea taxus) ▪ R. P. Lampe and M. A. Sovada YELLOW-BILLED CUCKOO BREEDING IN NORTH DAKOTA ▪ T. A. Gatz, J. P. Oswald, R. Randall, H. Bliss and P. Hlavinka EUSTRONGYLIDES AND PESTICIDE LEVELS IN A GREAT BLUE HERON SHOT IN WISCONSIN ▪ R. M. Windingstad and D. M. Swineford NOTE: Hooded Warbler in Cass County, North Dakota ▪ G. E. Neilsen BOOK REVIEW: A Pioneer in Conservation ▪ B. Pinkowsk

THE PRAIRIE NATURALIST Volume 13, Numbers 3 and 4. September - December 1981

PROVISIONAL CHECKLIST OF MAMMALS OF SOUTH DAKOTA ▪ J. R. Choate and J. K. Jones, Jr. LABORATORY FEEDING PREFERENCES OF THREE SMALL MAMMALS FOR FIVE TREE SPECIES ▪ T. G. Barnes and T. A. Schaid NESTLING DIETS OF RED-WINGED AND YELLOW-HEADED BLACKBIRDS ON PLAYA LAKES OF WEST TEXAS ▪ D. H. Fischer and E. C. Bolen COMPARISON OF FOUR NORTH DAKOTA IMPOUNDMENTS AND FACTORS AFFECTING THE DEVELOPMENT OF IMPOUNDMENT PARASITOFAUNA ▪ H. L. Holloway, Jr. and N. T. Hagstrom FIRST STATE RECORD OF RICHARDSON\u27S GROUND SQUIRREL IN IOWA ▪ R. P. Lampe, J. B. Bowles, and R. Spengler THE EFFECT OF AGE ON ADULT RED FOX BODY WEIGHTS ▪ S. H. Allen and J. Gulke SMALL MAMMALS ON REVEGETATED AGRICULTURAL LAND IN EASTERN COLORADO M. P. Moulton, J. R. Choate and S. J. Bissell HABIT AT PARTITIONING BY EASTERN AND DESERT COTTONTAILS IN SOUTHWESTERN NORTH DAKOTA ▪ D. J. Bergeron and R. W. Seabloom NOTE: An Albino Mule Deer in Southeastern Montana ▪ W. L. Matthews and W. R. Linderfelt BOOK REVIEW: Janovy II ▪ K. T Killingbeck NOTICE TO AUTHORS ▪ Editor INDEX TO VOLUME 1

Connexins: synthesis, post-translational modifications, and trafficking in health and disease

Connexins are tetraspan transmembrane proteins that form gap junctions and facilitate direct intercellular communication, a critical feature for the development, function, and homeostasis of tissues and organs. In addition, a growing number of gap junction-independent functions are being ascribed to these proteins. The connexin gene family is under extensive regulation at the transcriptional and post-transcriptional level, and undergoes numerous modifications at the protein level, including phosphorylation, which ultimately affects their trafficking, stability, and function. Here, we summarize these key regulatory events, with emphasis on how these affect connexin multifunctionality in health and disease

Theoretical Uncertainties in Red Giant Branch Evolution: The Red Giant Branch Bump

A Monte Carlo simulation exploring uncertainties in standard stellar evolution theory on the red giant branch of metal-poor globular clusters has been conducted. Confidence limits are derived on the absolute V-band magnitude of the bump in the red giant branch luminosity function (M_v,b) and the excess number of stars in thebump, R_b. The analysis takes into account uncertainties in the primordial helium abundance, abundance of alpha-capture elements, radiative and conductive opacities, nuclear reaction rates, neutrino energy losses, the treatments of diffusion and convection, the surface boundary conditions, and color transformations. The uncertainty in theoretical values for the red giant bump magnitude varies with metallicity between +0.13/-0.12 mag at [Fe/H] = -2.4 and +0.23/-0.21 mag at [Fe/H] = -1.0$. The dominant sources of uncertainty are the abundance of the alpha-capture elements, the mixing length, and the low-temperature opacities. The theoretical values of M_v,b are in good agreement with observations. The uncertainty in the theoretical value of R_b is +/-0.01 at all metallicities studied. The dominant sources of uncertainty are the abundance of the alpha-capture elements, the mixing length, and the high-temperature opacities. The median value of R_b varies from 0.44 at [Fe/H] = -2.4$ to 0.50 at [Fe/H] = -1.0. These theoretical values for R_b are in agreement with observations.Comment: 30 pages, 6 figures. To appear in Ap

Cosmological Implications of the Tetron Model of Elementary Particles

Based on a possible solution to the tetron spin problem, a modification of the standard Big Bang scenario is suggested, where the advent of a spacetime manifold is connected to the appearance of tetronic bound states. The metric tensor is constructed from tetron constituents and the reason for cosmic inflation is elucidated. Furthermore, there are natural dark matter candidates in the tetron model. The ratio of ordinary to dark matter in the universe is calculated to be 1:5.Comment: 23 page

Iso-osmotic regulation of nitrate accumulation in lettuce (Lactuca sativa L.)

Concerns about possible health hazards arising from human consumption of lettuce and other edible vegetable crops with high concentrations of nitrate have generated demands for a greater understanding of processes involved in its uptake and accumulation in order to devise more sustainable strategies for its control. This paper evaluates a proposed iso-osmotic mechanism for the regulation of nitrate accumulation in lettuce (Lactuca sativa L.) heads. This mechanism assumes that changes in the concentrations of nitrate and all other endogenous osmotica (including anions, cations and neutral solutes) are continually adjusted in tandem to minimise differences in osmotic potential of the shoot sap during growth, with these changes occurring independently of any variations in external water potential. The hypothesis was tested using data from six new experiments, each with a single unique treatment comprising a separate combination of light intensity, N source (nitrate with or without ammonium) and nitrate concentration carried out hydroponically in a glasshouse using a butterhead lettuce variety. Repeat measurements of plant weights and estimates of all of the main soluble constituents (nitrate, potassium, calcium, magnesium, organic anions, chloride, phosphate, sulphate and soluble carbohydrates) in the shoot sap were made at intervals from about 2 weeks after transplanting until commercial maturity, and the data used to calculate changes in average osmotic potential in the shoot. Results showed that nitrate concentrations in the sap increased when average light levels were reduced by between 30 and 49 % and (to a lesser extent) when nitrate was supplied at a supra-optimal concentration, and declined with partial replacement of nitrate by ammonium in the external nutrient supply. The associated changes in the proportions of other endogenous osmotica, in combination with the adjustment of shoot water content, maintained the total solute concentrations in shoot sap approximately constant and minimised differences in osmotic potential between treatments at each sampling date. There was, however, a gradual increase in osmotic potential (ie a decline in total solute concentration) over time largely caused by increases in shoot water content associated with the physiological and morphological development of the plants. Regression analysis using normalised data (to correct for these time trends) showed that the results were consistent with a 1:1 exchange between the concentrations of nitrate and the sum of all other endogenous osmotica throughout growth, providing evidence that an iso-osmotic mechanism (incorporating both concentration and volume regulation) was involved in controlling nitrate concentrations in the shoot

Nitrate pollution from horticultural production systems : tools for policy and advice from field to catchment scales

The implementation of the Nitrates Directive has imposed a requirement to restrict N fertiliser and manuring practices on farms across the EU in order to reduce nitrate losses to water. These requirements have since been extended by the more demanding Water Framework Directive, which broadens the focus from the control of farm practices to a consideration of the impacts of pollutants from all sources on water quality at a catchment or larger scale. Together, these Directives set limits for water quality, and identify general strategies for how these might be achieved. However, it is the responsibility of policy makers in each Nation State to design the details of the management practices and environmental protection measures required to meet the objectives of the legislation, to ensure they are appropriate for their specific types of land use and climate. This paper describes various modelling tools for comparing different cropping and land use strategies, and illustrates with examples how they can inform policy makers about the environmental benefits of changing management practices and how to prioritise them. The results can help to provide the specific advice on N fertiliser and land use management required by farmers and growers at a field scale, and by environmental managers at a catchment or larger scale. A further example of how results from multiple catchments can be up-scaled and compared using Geographic Information Systems is also outlined

The Forward-Backward Asymmetry in NNLO QCD

We have recently calculated the second-order QCD corrections to the forward-backward asymmetry in e+e- annihilation (hep-ph/9905424). Here we recall the results and compare them to others in the literature.Comment: 14 pages, LaTeX, uses lathuile.sty (included). Talk given by M. Seymour at 13th Rencontres de Physique de la Vallee d'Aoste, Results and Perspectives in Particle Physics, La Thuile, Aosta Valley, Italy, February 28th-March 6th, 199