Case Study of On-Farm Experiments and Farm Management Decision Making

Farm Management,

The potential impact on Florida-based marina and boating industries of a post-embargo Cuba: an analysis of geographic, physical, policy and industry trends

The information in this Technical Paper addresses the future of the US-Cuban marina and recreational boating industries from the geographic, physical, policy making and economic perspectives for a post-embargo Cuba. Each individual paper builds on the presentations made at the workshop, the information obtained in the subsequent trip to Cuba and presents in detailed form information which we hope is useful to all readers. (147pp.

THE U.S. DAIRY INDUSTRY

Agribusiness,

The Biology of the Soricidae

The papers published in this volume were originally presented in a symposium entitled The Biology of the Soricidae at the 67th annual meeting of the American Society of Mammalogists, held in June 1987 at the University of New Mexico in Albuquerque. When we organized the symposium, we had two goals in mind. First, we wished to assemble speakers currently studying diverse aspects of soricid biology to enable us to survey the breadth of ongoing research on this relatively little-studied group of small mammals. Second, we hoped to stimulate further research on soricids by highlighting problems and raising questions that can and should be addressed in the future. The papers in this volume deal with current research on the ecology, behavior, physiology, biogeography, and systematics of shrews. Williams examines the distribution of soricids along an altitudinal transect on the western slope of California\\u27s Sierra Nevada, where five species of Sorex occur. He found that in each major vegetational zone, one species dominated the soricid community. This contrasted with the situation on the eastern slope of the Sierra Nevada and in other forest communities in North America, where soricid communities may consist of up to five species. Kirkland examines this phenomenon further, seeking to explain the high species richness of many soricid communities. He concludes that, although the small size of shrews may facilitate coexistence by permitting shrews to exploit resources in a more coarse-grained fashion, environmental moisture is the factor that determines resource availability and ultimately the potential richness of soricid communities. Churchfield confirms this observation with a fine-grained analysis of soricid communities consisting of species with varying foraging techniques. Her data also suggest that in more diverse communities dietary generalists may outnumber dietary specialists. McNab contrasts metabolic rates in crocidurine and soricine shrews, demonstrating that soricines are capable of far more precise body temperature regulation than crocidurines. He suggests that this is a direct reflection of the respective distributions of these largely allopatric subfamilies. The predominantly tropical and warm-temperate crocidurines face considerably less environmental stress than soricine shrews, which are largely temperate and sub-boreal in distribution. Merritt and Adamerovich explore the winter physiology of a soricine shrew, Blarina brevicauda, and confirm that this species does not employ torpor or communal nesting to deal with cold winter temperature; however, winter survival is facilitated by prey-caching behavior and the construction of elaborate networks of tunnels at depths that insulate these shrews from cold temperatures. The systematic works examine morphologic variability in two species complexes of Sorex. In an analysis of populations of Sorex cinereus from North America and eastern Siberia, van Zyll de Jong divides the species into three subgroups. The biogeographic history of this species corresponds well to vicariance models of the Pleistocene history of North America and Beringia. George and Smith examine cranial variability in two commonly confused species, Sorex vagrans and S. monticolus, in the Pacific Northwest of North America. They quantify cranial variability within and among populations of each species, documenting an increase in cranial size in populations of S. vagrans on the Gulf and San Juan Islands between Vancouver Island and the mainland. Shrews occupy a broad spectrum of habitats throughout the Holarctic and much of the Old World tropics. They commonly coexist in multispecies communities, despite the fact that (to us) they appear to vary little in size, overall morphology, and ecological strategy. Compared to many other small mammals, shrews are difficult to catch, maintain, and manipulate. As a consequence, relatively little research has been conducted to answer basic questions regarding their ecology, physiology, and systematics. The seven papers included in this volume attempt to explore a few of these questions. We hope that these papers will stimulate the reader to undertake further research in these areas as well as on aspects of soricid biology not addressed in this volume

A Relationship Between River Modification and Species Richness of Freshwater Turtles in Iowa

Comparisons were made of turtle populations in Red Rock Reservoir and the major rivers of the Mississippi River and Missouri River damage systems in Iowa. Of the inland rivers of the Mississippi drainage examined in this study, the Des Moines River had the least amount of remaining turtle habitat. Number of turtle species ranged from five in the Des Moines River to 11 in the Mississippi River, but only three species were found in Red Rock Reservoir. In the Missouri drainage, number of turtle species ranged from three in both the Little Sioux and Nishnabotna rivers to five in the Missouri River. Regression analysis found remaining turtle habitat to be the strongest predictor of species richness. Stream modification appeared to lower the species richness of riverine turtles by eliminating intolerant species. Intolerant forms were absent when river modification eliminated their habitat and created a more uniform and simplified environment Map turtles (Graptemys geographica LeSueur), false map turtles (Graptemys pseudogeographica Gray), Blanding\u27s turtles (Emydotdea blandingi Holbrook), and smooth soft-shells (Apalone mutica LeSueur), appeared to be most affected by modification. Turtle species richness was lower in Red Rock Reservoir than in the Des Moines River, possibly due to the great fluctuation in the water level of the reservoir

COMPARING MANAGEMENT SYSTEMS FOR BEEF CATTLE BACKGROUNDING: A MULTIDISCIPLINARY APPROACH

Livestock Production/Industries,

Polyimide processing additives

A process for preparing polyimides having enhanced melt flow properties is described. The process consists of heating a mixture of a high molecular weight poly-(amic acid) or polyimide with a low molecular weight amic acid or imide additive in the range of 0.05 to 15 percent by weight of additive. The polyimide powders so obtained show improved processability, as evidenced by lower melt viscosity by capillary rheometry. Likewise, films prepared from mixtures of polymers with additives show improved processability with earlier onset of stretching by TMA

Intermittent electron density and temperature fluctuations and associated fluxes in the Alcator C-Mod scrape-off layer

The Alcator C-Mod mirror Langmuir probe system has been used to sample data time series of fluctuating plasma parameters in the outboard mid-plane far scrape-off layer. We present a statistical analysis of one second long time series of electron density, temperature, radial electric drift velocity and the corresponding particle and electron heat fluxes. These are sampled during stationary plasma conditions in an ohmically heated, lower single null diverted discharge. The electron density and temperature are strongly correlated and feature fluctuation statistics similar to the ion saturation current. Both electron density and temperature time series are dominated by intermittent, large-amplitude burst with an exponential distribution of both burst amplitudes and waiting times between them. The characteristic time scale of the large-amplitude bursts is approximately 15{\mu}s. Large-amplitude velocity fluctuations feature a slightly faster characteristic time scale and appear at a faster rate than electron density and temperature fluctuations. Describing these time series as a superposition of uncorrelated exponential pulses, we find that probability distribution functions, power spectral densities as well as auto-correlation functions of the data time series agree well with predictions from the stochastic model. The electron particle and heat fluxes present large-amplitude fluctuations. For this low-density plasma, the radial electron heat flux is dominated by convection, that is, correlations of fluctuations in the electron density and radial velocity. Hot and dense blobs contribute approximately 6% of the total fluctuation driven heat flux

MULTISPECIES REVENUE FUNCTION ESTIMATION FOR NORTH PACIFIC GROUNDFISH FISHERIES

Multiproduct, multispecies revenue functions are estimated for the midwater and bottom-trawl pollock fisheries off Alaska. There are strong year and seasonal effects on coefficient estimates, and the technology is joint in outputs for each major operation type. The model is a step toward prediction of fishery regulatory effects.Resource /Energy Economics and Policy,