1,455 research outputs found

    Location of pattern-disturbing structures in the vicinity of an antenna Final report, Jun. 5, 1963 - Sep. 15, 1966

    Get PDF
    Location of radiation pattern disturbing structures in vicinity of satellite antenn

    Intimate Partner Violence in Rural Areas

    Get PDF
    Intimate partner violence is a major health care issue in the United States, affecting millions of women annually. The incidence and prevalence of intimate partner violence is essentially the same in rural areas as compared to non-rural; however, rural survivors are faced with barriers in obtaining help and services that non-rural survivors are not. Multiple mental and physical health problems are associated with intimate partner violence and billions of health care dollars are spent annually due to abuse. Nurses need to understand the problem of intimate partner violence and routinely screen all women for abuse. This article describes the unique aspects of intimate partner violence among rural populations. It also provides a screening tool that can be used in all clinics and suggests ways to approach the patient during their visit. It has been concluded that if more women are screened then more women will disclose abuse. The health care team can then help these women seek needed resources to help keep them safe. This in tum will decrease serious health sequelae and the amount of health care dollars spent

    Antenna arrays - Efficiency and efficiency improvement through compensation

    Get PDF
    Design procedures for compensating phased array antenna elements for impedance changes with scan angl

    Study of inexact modeling techniques Final report

    Get PDF
    Scale modeling antenna systems for aircraft and missiles with anechoic chamber evaluation and us

    Effects of increased salinity and an introduced predator on lowland amphibians in southern China: species identity matters

    Get PDF
    abstract no. V-01-9Approximately 30% of amphibian species are threatened due to a variety of factors affecting their habitats and physiology, yet contributions that interactions among factors make to population declines are not well-explored. Two factors, introduced mosquitofish (Gambusia affinis) and increased salinity, may coincide in lowland habitats used by breeding amphibians. Mosquitofish have been introduced worldwide and can be significant predators of amphibian larvae. Salinization of wetlands is an increasing problem globally due to (1) application of road deicing salts in temperate regions, (2) irrigation practices associated with intensive agriculture, particularly in Australia, and (3) saltwater intrusion due to sea-level rise. We investigated the effects of mosquitofish (Gambusia affinis) and increasing salinity on five species of lowland wetland-breeding amphibians from southern China. We exposed anuran hatchlings to four salinity levels and two fish treatments and all combinations of the two factors in a series of experiments. Four of the species were susceptible to predation by mosquitofish, two were sensitive to increased salinity at concentrations >6% seawater, and one was tolerant of both increased salinity and mosquitofish. We found no interaction between the predator and increased salinity. Salinization and mosquitofish represent significant threats to lowland amphibians in this region and, coupled with the ongoing loss and degradation of lowland wetlands, portend a bleak future for lowland amphibian populations in the region.postprintThe 49th Annual Meeting of the Association for Tropical Biology and Conservation (ATBC 2010), Bali, Indonesia, 19-23 July 2010. In Abstract Book of the 49th ATBC Annual Meeting, 2010, p.

    Physiological Responses to Environmental Variation in Intertidal Red Algae: Does Thallus Morphology Matter?

    Get PDF
    Morphological variation within and among many species of algae show correlated life history traits. The trade-offs of Life history traits among different morphs are presumed to be determined by morphology. Form-function hypotheses also predict that algae of different morphological groups exhibit different tolerances to physiological stress, whereas algae within a morphological group respond similarly to stress. We tested this hypothesis by comparing photosynthetic and respiratory responses to variation in season, light, temperature, desiccation and freezing among the morphologically similar fronds of Chondrus crispus and Mastocarpus stellatus and the alternate stage crust of M. stellatus. Physiological differences between fronds of the 2 species and crusts and fronds were consistent with their patterns of distribution and abundance in the intertidal zone. However, there was no clear relationship between algal morphology and physiological response to environmental variation. These results suggest that among macroalgae the correlation between Life history traits and morphology is not always causal. Rather, the link between life history traits and morphology is constrained by the extent to which physiological characteristics codetermine these features

    Beveled Projectile Points and Ballistics Technology

    Get PDF
    Explanations for beveled blade edges on projectile points have been debated in North America archaeology since the first systematic description of lithic assemblages in the nineteenth century. Debate has centered around two opposing perspectives. One views beveled edges as features of projectile points that cause them to spin during flight. The other views beveling as a product of edge resharpening that is done unifacially to conserve scarce resources. Here we use a fluid-dynamics model to simulate the effect beveling has on projectiles. Expectations derived from this modeling are evaluated using wind-tunnel experiments. Our findings indicate that beveling produces in-flight rotation that serves as a means of increasing accuracy in relatively low-velocity flight paths.

    Explicit solutions for second order operator differential equations with two boundary value conditions

    Get PDF
    AbstractBoundary value problems for second order operator differential equations with two boundary value conditions are studied. Explicit expressions of the solutions in terms of data problems are given. By means of the application of algebraic techniques, analogous expressions to the ones known for the scalar case are obtained

    Distribution and abundance of fish and crayfish in a Waikato stream in relation to basin area

    Get PDF
    The aim of this study was to relate the longitudinal distribution of fish and crayfish to increasing basin area and physical site characteristics in the Mangaotama Stream, Waikato region, North Island, New Zealand. Fish and crayfish were captured with two-pass removal electroshocking at 11 sites located in hill-country with pasture, native forest, and mixed land uses within the 21.6 km2 basin. Number of fish species and lineal biomass of fish increased with increasing basin area, but barriers to upstream fish migration also influenced fish distribution; only climbing and non-migratory species were present above a series of small waterfalls. Fish biomass increased in direct proportion to stream width, suggesting that fish used much of the available channel, and stream width was closely related to basin area. Conversely, the abundance of crayfish was related to the amount of edge habitat, and therefore crayfish did not increase in abundance as basin area increased. Densities of all fish species combined ranged from 17 to 459 fish 100 m-2, and biomass ranged from 14 to 206 g m-2. Eels dominated the fish assemblages, comprising 85-100% of the total biomass; longfinned eels the majority of the biomass at most sites. Despite the open access of the lower sites to introduced brown trout, native species dominated all the fish communities sampled

    Physical Activity and Immunity in HIV-Infected Individuals

    Get PDF
    The purpose of this study was to determine what relationship exists among physical activity levels and viral load and CD4+ cell count in HIV-infected individuals. Increased viral load is associated with disease progression and symptom severity. A convenience sample of 66 male and female subjects between the ages of 18 and 64 years of age (mean 399/8) was recruited from a hospital-based HIV/AIDS clinic. Components of PA were assessed for three continuous days using a mini-motion logger wrist actigraph. These components included mean PA level, and PA index and acceleration index. Pearson’s correlational analysis was used to test the strength of association between PA components and viral load or CD4+ cell count. A significant inverse relationship was found between mean PA level and viral load (p=0.047). An inverse relationship was also observed between PA index and viral load (p=0.0061). Neither mean PA nor PA index scores correlated with CD4+ cell counts. Acceleration index, a measure of PA intensity, showed no correlation to viral load or CD4+ cell counts. These findings suggest that increasing levels of physical activity might have beneficial effects on viral load in HIV-infected individuals
    corecore