1,799 research outputs found

    WHAT CAN A KANSAS FARMER AFFORD TO PAY TO RENT CROPLAND?

    Get PDF
    Five years of continuous annual data are used to measure the marginal value product of cropland (return to land) on approximately 100 Kansas farms. Determinants of the marginal value product are investigated using regression.Land Economics/Use,

    Genetic implications of reduced survival of male red deer \u3ci\u3eCervus elaphus\u3c/i\u3e under harvest

    Get PDF
    We use simple, multivariate evolutionary models to evaluate the short-term potential for size-selective harvest to reduce genetic variability and alter life history in cervids. These genetic effects limit sustainable levels of harvest of the animals because they determine how changes in sex ratio, generation length and traits contributing to fitness influence population growth rate and local adaptation. Our analysis of harvest-mediated adaptive evolution employs a genetic approach that parameterizes models with empirical data obtained from European red deer Cervus elaphus. The analysis indicates that harvest, if sufficiently high to reduce the breeding ratio of males to females to below about 15:100, can reduce effective population size to a level that threatens adaptive potential. The reduction in effective size is realized through decreases in both sex ratio of breeders and the age of breeding males. Predicted selective effects of harvest on body size indicates a weak potential to alter most life-history traits over 10 generations under two harvest scenarios; the patterns suggest that current modes of harvest are unlikely to produce substantial life-history changes in red deer over 10 or fewer generations unless the genetic influences on red deer traits are considerably higher than those predicted here. Nevertheless, male reproductive success is expected to decline detectably if male harvest rate is sufficiently high (\u3e30%). Collectively, our results imply that harvest methods should permit higher post-hunt male:female ratios (18:100 or higher) and ensure that a sufficient number of larger, older males survive the breeding season. The capacity of selective harvest to alter demography and life history depends heavily on the genetic covariance structure underlying variation in these traits, information that is unknown for many red deer populations. Prudent harvest management should therefore implement and monitor approaches to hunting that aim to conserve life-history variation; meanwhile, use of less selective methods can reduce the risk to long-term adaptive potential and may permit higher sustainable harvest rates

    Electronic Health Record Availability and Anxiety Treatment in Office Based Practices

    Get PDF
    Objective: This study compared the probability of receiving anxiety treatment during a physician visit to primary care practices with and without an electronic health record (EHR). Methods: The 2007–2010 National Ambulatory Medical Care Survey was used to identify visits for anxiety (N=290). The outcome was receipt of anxiety treatment. The independent variable was the presence of a fully functioning EHR. Logistic regression was used to conduct the analysis. Results: Patients who were seen in practices with a fully functioning EHR had lower odds of being offered antianxiety medication (adjusted odds ratio [AOR]=.37, 95% confidence interval [CI]=.15–.90, p=.028), mental health counseling (AOR=.43, CI=.18–1.04, p=.061), and any anxiety treatment (AOR=.40, CI=.15–1.05, p=.062) compared with patients at practices without a fully functioning EHR. Conclusions: EHRs may have a negative impact on the delivery of care for anxiety during primary care visits. Future studies should monitor the impact of EHRs on delivery and quality of care

    The comparative impact of different patient-centered medical home domains on satisfaction among individuals living with type II diabetes

    Get PDF
    Chronic illnesses like type 2 diabetes are costly and difficult to treat. Patient-centered medical homes (PCMH) have the potential to improve patient satisfaction in this population. However, which domains have the most impact on patient satisfaction has not been established. The aim of this study was to assess the relative strength of association between seven PCMH domains and two measures of satisfaction. Cross-sectional data were used in this observational study collected from a random sample of adults aged 18-89 with type 2 diabetes (n=1301) seen at 4 PCMHs. The Ambulatory Care Experiences Survey instrument was used to assess all measures. Dependent variables included 2 measures of patient satisfaction: overall care and personal doctor. Independent variables included patient perceptions of implementation level of 7 PCMH domains categorized into two dimensions: administrative features of care and physician-patient interactions. Administrative features of care include organizational access, integration of care and office staff helpfulness. Physician-patient interactions include communication, comprehensive knowledge and interpersonal treatment. Analysis was conducted using linear regression. The results reveal all physician-patient interaction PCMH domains were significantly associated with both measures of satisfaction. The relationships for administrative features of care were dependent upon the satisfaction outcome being analyzed. Communication and comprehensive knowledge had the strongest association of all domains. The authors conclude variations in importance of PCMH domains on satisfaction exist. Physician-patient interaction domains are the strongest contributors to patient satisfaction and overall experience. Understanding which PCMH domains have the largest impact can inform physician practice’s efforts to improve outcomes of care

    Adenovirus RIDα regulates endosome maturation by mimicking GTP-Rab7

    Get PDF
    The small guanosine triphosphatase Rab7 regulates late endocytic trafficking. Rab7-interacting lysosomal protein (RILP) and oxysterol-binding protein–related protein 1L (ORP1L) are guanosine triphosphate (GTP)–Rab7 effectors that instigate minus end–directed microtubule transport. We demonstrate that RILP and ORP1L both interact with the group C adenovirus protein known as receptor internalization and degradation α (RIDα), which was previously shown to clear the cell surface of several membrane proteins, including the epidermal growth factor receptor and Fas (Carlin, C.R., A.E. Tollefson, H.A. Brady, B.L. Hoffman, and W.S. Wold. 1989. Cell. 57:135–144; Shisler, J., C. Yang, B. Walter, C.F. Ware, and L.R. Gooding. 1997. J. Virol. 71:8299–8306). RIDα localizes to endocytic vesicles but is not homologous to Rab7 and is not catalytically active. We show that RIDα compensates for reduced Rab7 or dominant-negative (DN) Rab7(T22N) expression. In vitro, Cu2+ binding to RIDα residues His75 and His76 facilitates the RILP interaction. Site-directed mutagenesis of these His residues results in the loss of RIDα–RILP interaction and RIDα activity in cells. Additionally, expression of the RILP DN C-terminal region hinders RIDα activity during an acute adenovirus infection. We conclude that RIDα coordinates recruitment of these GTP-Rab7 effectors to compartments that would ordinarily be perceived as early endosomes, thereby promoting the degradation of selected cargo

    Resistance exercise training restores bone mineral density in heart transplant recipients

    Get PDF
    AbstractObjectives. This was a prospective, randomized, controlled study designed to determine the effect of resistance exercise traning on bone metabolism in heart transplant recipients.Background. Osteoporosis frequently complicates heart transplantation. No preventative strategy is generally accepted for glucocorticoid-induced bone loss.Methods. Sixteen male heart transplant recipients were randomly assigned to a resistance exercise group that trained for 6 months (mean [±SD] age 56 ± 6 years) or a control group (mean age 52 ± 10 years) that did not perform resistance exercise. Bone mineral density (BMD) of the total body, femur neck and lumbar spine (L2 to L3) was measured by dual-energy X-ray absorptiometry before and 2 months after transplantation and after 3 and 6 months of resistance exercise or a control period. The exercise regimen consisted of lumbar extension exercise (MedX) performed 1 day/week and variable resistance exercises (Nautilus) performed 2 days/week. Each exercise consisted of one set of 10 to 15 repetitions performed to volitional fatigue.Results. Pretransplantation baseline values for regional BMD did not differ in the control and training groups. Bone mineral density of the total body, femur neck and lumbar vertebra (L2 to L3) were significantly decreased below baseline at 2 months after transplantation in both the control (−3.3 ± 1.3%, − 4.5 ± 2.8%, −12.7 ± 6.2%, respectly) and training groups (−2.9 ± 1.1%, 5.9 ± 3.2%, −14.8 ± 3.1%, respectively). Six months of resistance exercise restored BMD of the whole body, femur neck and lumbar vertebra to within 1%, 1.9% and 3.6% of pretransplantation levels, respectively. Bone mineral density of the control group remained unchanged from the 2-month posttransplantation levels.Conclusions. Within 2 months after heart transplantation, ≈ 3% of whole-body BMD is lost, mostly due to decreases in trabecular bone (−12% to −15% of lumbar vertebra). Six months of resistance exercise, consisting of low back exercise that isolates the lumbar spine and a regimen of variable resistance exercises, restores BMD toward pretransplantation levels. Our results suggest that resistance exercise is osteogenic and should be initiated early after heart transplantation

    Function and underlying mechanisms of seasonal colour moulting in mammals and birds: what keeps them changing in a warming world?

    Get PDF
    Animals that occupy temperate and polar regions have specialized traits that help them survive in harsh, highly seasonal environments. One particularly important adaptation is seasonal coat colour (SCC) moulting. Over 20 species of birds and mammals distributed across the northern hemisphere undergo complete, biannual colour change from brown in the summer to completely white in the winter. But as climate change decreases duration of snow cover, seasonally winter white species (including the snowshoe hare Lepus americanus, Arctic fox Vulpes lagopus and willow ptarmigan Lagopus lagopus) become highly contrasted against dark snowless backgrounds. The negative consequences of camouflage mismatch and adaptive potential is of high interest for conservation. Here we provide the first comprehensive review across birds and mammals of the adaptive value and mechanisms underpinning SCC moulting. We found that across species, the main function of SCC moults is seasonal camouflage against snow, and photoperiod is the main driver of the moult phenology. Next, although many underlying mechanisms remain unclear, mammalian species share similarities in some aspects of hair growth, neuroendocrine control, and the effects of intrinsic and extrinsic factors on moult phenology. The underlying basis of SCC moults in birds is less understood and differs from mammals in several aspects. Lastly, our synthesis suggests that due to limited plasticity in SCC moulting, evolutionary adaptation will be necessary to mediate future camouflage mismatch and a detailed understanding of the SCC moulting will be needed to manage populations effectively under climate change

    Mechanisms by which sialylated milk oligosaccharides impact bone biology in a gnotobiotic mouse model of infant undernutrition

    Get PDF
    Undernutrition in children is a pressing global health problem, manifested in part by impaired linear growth (stunting). Current nutritional interventions have been largely ineffective in overcoming stunting, emphasizing the need to obtain better understanding of its underlying causes. Treating Bangladeshi children with severe acute malnutrition with therapeutic foods reduced plasma levels of a biomarker of osteoclastic activity without affecting biomarkers of osteoblastic activity or improving their severe stunting. To characterize interactions among the gut microbiota, human milk oligosaccharides (HMOs), and osteoclast and osteoblast biology, young germ-free mice were colonized with cultured bacterial strains from a 6-mo-old stunted infant and fed a diet mimicking that consumed by the donor population. Adding purified bovine sialylated milk oligosaccharides (S-BMO) with structures similar to those in human milk to this diet increased femoral trabecular bone volume and cortical thickness, reduced osteoclasts and their bone marrow progenitors, and altered regulators of osteoclastogenesis and mediators of Th2 responses. Comparisons of germ-free and colonized mice revealed S-BMO-dependent and microbiota-dependent increases in cecal levels of succinate, increased numbers of small intestinal tuft cells, and evidence for activation of a succinate-induced tuft cell signaling pathway linked to Th2 immune responses. A prominent fucosylated HMO, 2'-fucosyllactose, failed to elicit these changes in bone biology, highlighting the structural specificity of the S-BMO effects. These results underscore the need to further characterize the balance between, and determinants of, osteoclastic and osteoblastic activity in stunted infants/children, and suggest that certain milk oligosaccharides may have therapeutic utility in this setting

    Gaming motivation and problematic video gaming: The role of needs frustration

    Get PDF
    Motivation is often used as a predictor of a problematic style of video game engagement, implying that individuals' gaming undermines optimal functioning. Drawing from recent advances in Self-Determination Theory (SDT), the present study explores the links between gaming motivations, the daily frustration of basic psychological needs, and reports of problematic video gaming (PVG). A sample of 1029 participants (72.8% male; M = 22.96 years; SD = 4.13 years) completed items regarding their gaming engagement and gaming motivation as well as their experience of needs frustration and PVG symptoms. Results revealed positive associations between gaming motivations and PVG, and between daily needs frustration and PVG. Finally, after comparing several competing models, a mediational model whereby needs frustration explained the association between individuals' gaming motivation and PVG emerged as best fitting the data. The discussion addresses the theoretical and practical implications of these findings in the context of recent research

    Comparative effectiveness of dual-action versus single-action antidepressants for the treatment of depression in people living with HIV/AIDS

    Get PDF
    Background Depression is the most common psychiatric comorbidity among people living with HIV/AIDS (PLWHA). Little is known about the comparative effectiveness between different types of antidepressants used to treat depression in this population. We compared the effectiveness of dual-action and single-action antidepressants in PLWHA for achieving remission from depression. Methods We used data from the Centers for AIDS Research Network of Integrated Clinic Systems to identify 1175 new user dual-action or single-action antidepressant treatment episodes occurring from 2005 to 2014 for PLWHA diagnosed with depression. The primary outcome was remission from depression defined as a Patient Health Questionnaire-9 (PHQ-9) score <5. Mean difference in PHQ-9 depressive symptom severity was a secondary outcome. The main approach was an intent-to-treat (ITT) evaluation complemented with a per protocol (PP) sensitivity analysis. Generalized linear models were fitted to estimate treatment effects. Results In ITT analysis, 32% of the episodes ended in remission for both dual-action and single-action antidepressants. The odds ratio (OR) of remission was 1.02 (95%CI=0.63,1.67). In PP analysis, 40% of dual-action episodes ended in remission compared to 32% in single-action episodes. Dual-action episodes had 1.33 times the odds of remission (95%CI=0.55,3.21), however the result was not statistically significant. Non-significant differences were also observed for depressive symptom severity. Limitations Missing data was common but was addressed with inverse probability weights. Conclusions Results suggest that single-action and dual-action antidepressants are equally effective in PLWHA. Remission was uncommon highlighting the need to identify health service delivery strategies that aid HIV providers in achieving full remission of their patients’ depression
    • 

    corecore