1,839 research outputs found

    Impact of sagebrush nutrients and monoterpenes on greater sage-grouse vital rates

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    Greater sage-grouse (Centrocercus urophasianus; sage-grouse) depend on sagebrush (Artemisia spp.) to complete its annual life cycle. The winter diet for sage-grouse consists almost entirely of sagebrush leaves, and individual birds may gain weight while foraging on sagebrush. Previous studies have reported higher crude protein and lower monoterpene concentrations in the sagebrush species selected as winter forage by sagegrouse. However, no studies have attempted to link female sage-grouse vital rates (i.e., nest initiation and success, egg fertility, clutch size, and adult survival) to crude protein or monoterpene concentrations of sagebrush plants browsed during pre-nesting periods. From March to May 2013, we monitored pre-nesting diets for 29 radio-marked female sage-grouse in the Box Elder Sage-grouse Management Area in northwestern Utah to determine if a relationship existed between foraging patterns and vital rates. We randomly located radiomarked female sage-grouse ≥3 times during the study period and subsequently sampled 70 sagebrush communities where they were observed to determine which sagebrush species or subspecies were browsed and if samples collected of the browsed plants differed in nutritional quality (i.e., crude protein) and chemical composition (i.e., monoterpenes) from non-browsed plants in the areas sampled and non-browsed randomly selected plants in adjacent sagebrush communities. Seventy-three percent of these sites where radio-marked females were located consisted entirely of black sagebrush (A. nova) communities. Percent crude protein and total monoterpene concentration in black sagebrush and Wyoming big sagebrush (A. tridentata wyomingensis) did not diff er between browsed, non-browsed, and non-browsed random plants. Browsed black sagebrush plants were lower in average percent crude protein (P = 0.003) and higher in total monoterpene concentration (P ≤ 0.001) than browsed Wyoming big sagebrush. Apparent nest success, age of nesting females, egg fertility, clutch size (P \u3e 0.05), and female monthly survival rates (CI = -0.21–0.49) for the radio-marked sagegrouse we monitored did not diff er based on sagebrush crude protein and total monoterpene content. However, all of the radio-marked female sage-grouse (n = 10) observed in black sagebrush communities where the collected plant samples exhibited higher concentrations of an unidentified monoterpene successfully hatched nests (P = 0.002). All of the nests of radiomarked female sage-grouse (n = 9) outside these areas failed. Our results lend additional support to previous published work regarding sage-grouse preferences for black sagebrush as pre-nesting forage and suggest a potential link to nest success

    Permittivity of Porous Titanate Dielectrics

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    Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/65907/1/j.1551-2916.2006.01323.x.pd

    The Role of Vegetation Structure, Composition, and Nutrition in Greater Sage-Grouse Ecology in Northwestern Utah

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    The greater sage-grouse (Centrocercus urophasianus; sage-grouse) is the largest grouse species in North America and an indicator species for the condition of sagebrush (Artemisia spp.) ecosystems. The Box Elder Sage-Grouse Management Area (SGMA) in northwestern Utah encompasses one of the state’s largest sage-grouse populations. To fill knowledge gaps regarding the population inhabiting the Raft River subunit of the Box Elder SGMA, I captured, radio-marked, and monitored 123 (68 female, 55 male) sage-grouse from January 2012 through December 2013. My purpose was to describe how the seasonal movements, survival, and reproductive rates of this sage-grouse population are effected by small-scale habitat use and breeding season foraging patterns. Sage-grouse in the Raft River subunit have distinct winter and summer ranges, and some travelled long distances annually. Survival rates were similar to other Utah populations and range-wide averages. Nest and brood success rates were above range-wide averages and those reported in the adjacent Grouse Creek subunit of the same SGMA. Sage-grouse in the study area selected habitats with specific vegetation characteristics to fit their seasonal needs. Sage-grouse use sites differed from random sites with greater forb height, grass height, and shrub height and cover. Nest success rates were directly related to selected vegetation, as successful nests were located more often under sagebrush and within greater forb height and cover and grass and shrub height than unsuccessful nests. Brood sites were also greater in forb, grass, and shrub height than other use sites. In March and April of 2013, I located radio-marked sage-grouse at flock browse sites to observe their sagebrush diet selection patterns. Lab analyses showed no differences in nutritional quality or chemical composition between browsed sagebrush plants and non-browsed and random plants. However, browsed black sagebrush (A. nova) was lower in protein and higher in chemical content than browsed Wyoming big sagebrush (A. tridentata wyomingensis). Radio-marked females were frequently observed at sites where black sagebrush was browsed, and one individual chemical was considerably more concentrated in browsed plants associated with females that nested successfully. My research provides useful information regarding the seasonal habitat use patterns and vegetation preferences of sage-grouse in the Box Elder SGMA. To conserve the sage-grouse population in northwestern Utah, management actions must protect the seasonal habitats and vegetation that the species depends on for its productivity and survival

    Impact of Pilot Delay and Non-Responsiveness on the Safety Performance of Airborne Separation

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    Assessing the safety effects of prediction errors and uncertainty on automationsupported functions in the Next Generation Air Transportation System concept of operations is of foremost importance, particularly safety critical functions such as separation that involve human decision-making. Both ground-based and airborne, the automation of separation functions must be designed to account for, and mitigate the impact of, information uncertainty and varying human response. This paper describes an experiment that addresses the potential impact of operator delay when interacting with separation support systems. In this study, we evaluated an airborne separation capability operated by a simulated pilot. The experimental runs are part of the Safety Performance of Airborne Separation (SPAS) experiment suite that examines the safety implications of prediction errors and system uncertainties on airborne separation assistance systems. Pilot actions required by the airborne separation automation to resolve traffic conflicts were delayed within a wide range, varying from five to 240 seconds while a percentage of randomly selected pilots were programmed to completely miss the conflict alerts and therefore take no action. Results indicate that the strategicAirborne Separation Assistance System (ASAS) functions exercised in the experiment can sustain pilot response delays of up to 90 seconds and more, depending on the traffic density. However, when pilots or operators fail to respond to conflict alerts the safety effects are substantial, particularly at higher traffic densities

    Act Now for Your Tomorrow: Final Report of the National Commission on Nursing Workforce for Long-Term Care

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    The nursing workforce shortage faced by long-term care providers stems from factors both outside and inside the organization and operation of long-term care services. The nursing shortage diminishes quality of care and increases the costs of providing services. Resolution of the long-term care nursing workforce challenge will require improvement of the recruitment and retention of nurses. The leadership for the efforts to improve the long-term care workforce must come from the community itself. New and sustained leadership for action by long-term care leaders is the critical factor necessary to the development of the recommended initiatives and the achievement of the goals of the National Commission on Nursing Workforce for Long-Term Care

    Safety Performance of Airborne Separation: Preliminary Baseline Testing

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    The Safety Performance of Airborne Separation (SPAS) study is a suite of Monte Carlo simulation experiments designed to analyze and quantify safety behavior of airborne separation. This paper presents results of preliminary baseline testing. The preliminary baseline scenario is designed to be very challenging, consisting of randomized routes in generic high-density airspace in which all aircraft are constrained to the same flight level. Sustained traffic density is varied from approximately 3 to 15 aircraft per 10,000 square miles, approximating up to about 5 times today s traffic density in a typical sector. Research at high traffic densities and at multiple flight levels are planned within the next two years. Basic safety metrics for aircraft separation are collected and analyzed. During the progression of experiments, various errors, uncertainties, delays, and other variables potentially impacting system safety will be incrementally introduced to analyze the effect on safety of the individual factors as well as their interaction and collective effect. In this paper we report the results of the first experiment that addresses the preliminary baseline condition tested over a range of traffic densities. Early results at five times the typical traffic density in today s NAS indicate that, under the assumptions of this study, airborne separation can be safely performed. In addition, we report on initial observations from an exploration of four additional factors tested at a single traffic density: broadcast surveillance signal interference, extent of intent sharing, pilot delay, and wind prediction error

    Immune Alterations in Rats Exposed to Airborne Lunar Dust

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    The lunar surface is covered by a layer of fine, reactive dust. Very little is known regarding the toxicity of lunar dust on human physiology. This study assessed the toxicity of airborne lunar dust exposure in rats on pulmonary and systemic immune parameters

    Pulmonary and Systemic Immune Response to Chronic Lunar Dust Inhalation

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    Background: Due to millennia of meteorite impact with virtually no erosive effects, the surface of the Moon is covered by a layer of ultrafine, reactive Lunar dust. Very little is known regarding the toxicity of Lunar dust on human physiology. Given the size and electrostatic characteristics of Lunar dust, countermeasures to ensure nonexposure of astronauts will be difficult. To ensure astronaut safety during any future prolonged Lunar missions, it is necessary to establish the effect of chronic pulmonary Lunar dust exposure on all physiological systems. Methods: This study assessed the toxicity of airborne lunar dust exposure in rats on pulmonary and system immune system parameters. Rats were exposed to 0, 20.8, or 60.8 mg/m3 of lunar dust (6h/d; 5d/wk) for up to 13 weeks. Sacrifices occurred after exposure durations of 1day, 7 days, 4 weeks and 13 weeks postexposure, when both blood and lung lavage fluid were collected for analysis. Lavage and blood assays included leukocyte distribution by flow cytometry, electron/fluorescent microscopy, and cytokine concentration. Cytokine production profiles following mitogenic stimulation were performed on whole blood only. Results: Untreated lavage fluid was comprised primarily of pulmonary macrophages. Lunar dust inhalation resulted in an influx of neutrophils and lymphocytes. Although the percentage of lymphocytes increased, the T cell CD4:CD8 ratio was unchanged. Cytokine analysis of the lavage fluid showed increased levels of IL1b and TNFa. These alterations generally persisted through the 13 week sampling. Blood analysis showed few systemic effects from the lunar dust inhalation. By week 4, the peripheral granulocyte percentage was elevated in the treated rats. Plasma cytokine levels were unchanged in all treated rats compared to controls. Peripheral blood analysis showed an increased granulocyte percentage and altered cytokine production profiles consisting of increased in IL1b and IL6, and decreased IL2 production. Conclusion: Lunar dust inhalation results in significant lung inflammation, and some systemic effects, that does not resolve through 13 weeks. Lunar dust may therefore represent a crew health risk during sortie or longduration Lunar missions

    Greater Sage-Grouse Resource Selection Drives Reproductive Fitness Under a Conifer Removal Strategy

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    The link between individual variation in resource selection (e.g., functional response) and fitness creates a foundation for understanding wildlife-habitat relationships. Although many anthropogenic activities adversely affect these relationships, it is largely unknown whether projects implemented to benefit wildlife populations actually achieve this outcome. For sagebrush (Artemisia spp.) obligate species such as the greater sage-grouse (Centrocercus urophasianus; sage-grouse), expansion of juniper (Juniperus spp.) and pinyon-pine (Pinus spp.; conifers) woodlands into sagebrush ecosystems has been identified as a conservation threat. This threat is intensified when a sagebrush ecosystem is bounded by naturally unsuitable habitats. As such, federal, state, and private land managers have implemented landscape-level management to remove conifers on thousands of hectares of sagebrush habitat across the western United States. Despite the scale of contemporary conifer treatments, little was previously known whether sage-grouse will occupy these manipulated landscapes and whether occupancy has consequences on fitness components. To address these questions, we monitored nest and brood success rates for 96 radio-marked sage-grouse from 2012-2015 that inhabited conifer-dominated landscapes in the Box Elder Sage-grouse Management Area in Utah where mechanical conifer removal projects were completed. We then linked sage-grouse resource selection to individual nest (n = 95) and brood (n = 56) success by incorporating random-slope Resource Selection Functions as explanatory predictors in a logistic brood success model. Using the novel approach of random slope covariates, we demonstrated that sage-grouse selected for nest and brooding sites closer to conifer removal areas and that the probability of individual nest and brood success declined (β = − 0.10 and β = − 0.74, respectively) as sage-grouse females selected sites farther from conifer removal areas. Our research provided the first evidence that mechanical conifer removal treatments can increase suitable available breeding habitats for female sage-grouse and that individuals who occupied these areas experienced enhanced nest and brood success

    Validation and application of health utilities index in Chinese subjects with down syndrome

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    Objectives: The objectives of the study were (1) to validate the Chinese version of Health Utilities Index (HUI-Ch); (2) to examine the Health-related Quality of Life (HRQoL) of Chinese subjects with Down syndrome (DS); and (3) to study the impact of chronic health conditions on HRQoL of Chinese with DS. Methods: The multiple choice questionnaire for scoring Health Utilities Index Mark 2 (HUI2) and Health Utilities Index Mark 3 (HUI3) was translated and validated. In addition to the HRQoL scores from HUI2 and HUI3, proxy-data on socio-demographics, and 10 common chronic health conditions for people with DS were collected and analyzed. Data analysis involves multiple imputation and multiple regression analysis to predict variations in HRQoL in relation to different factors. Lastly, a gradient interval was constructed on the number of chronic health conditions in relation to HRQoL. Results: HUI-Ch was validated according to standard guidelines. People with DS were found to have a lower HRQoL as compared to the general population, with the majority categorized as moderate or severe on the scale. Behavioral and hearing problems on HUI2, and hearing problems on HUI3 were found to be statistically significant predictors of a lower HRQoL score. A significant gradient relationship existed showing when the number of health problems increased, the HRQoL scores decreased. Conclusions: HUI-Ch is a valid instrument to assess HRQoL. It can have broad application in Chinese subjects with DS including the study of the impact of different chronic health conditions on their quality of life. The quantifiable nature of HUI-Ch will facilitate longitudinal study on the well-being of subjects with DS and evaluation of effectiveness of intervention programs in the near future
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