711 research outputs found

    Ecology and Life History of the Speckled Madtom, Noturus leptacanthus (Ictaluridae)

    Get PDF
    This research represents an effort to understand the life history, strategy, and ecological relationships of Noturus leptacanthus. In particular I have tried to compare the combination of low fecundity, large egg size, parental car , and marked sexual dimorphism in leptacanthus with the patterns of these parameters in other ictalurid species

    An investigation of screening for medical referral by Physical Therapists

    Get PDF
    Screening for medical referral is essential to physical therapist practice; however, no studies have examined medical screening across physical therapy practice settings. The purpose of this study was to determine if physical therapists in a variety of practice settings, given brief clinical vignettes, would screen for medical referral in a similar manner. The Delphi Technique was implemented to establish content validity, although only 2 vignettes reached 100% consensus by the expert panel. After reviewing the vignettes, physical therapist subjects determined if they would provide intervention, provide intervention and refer, or refer before intervention. To determine which variables were associated with identified appropriate decisions in each category, 4 sets of logistic regressions were performed. A random sample of APTA members in targeted sections (n=214) completed the survey. Physical therapists with more than 23 years experience were 7 times more likely to make similar management decisions in noncritical vignettes then those with 11 years or less. Half of the participants practiced in outpatient practice settings. In critical medical vignettes, 86% of physical therapists made similar decisions. Physical therapists in this study made identified appropriate management decisions for 90% of the vignettes. Board certification, practice setting and highest earned degree were not found to be statistically significant. It is imperative not only to ensure that the client is appropriate for physical therapy intervention, but it is also vital to recognize and identify signs and symptoms that warrant evaluation by other health care providers

    Lunar Cube Transfer Trajectory Options

    Get PDF
    Numerous Earth-Moon trajectory and lunar orbit options are available for Cubesat missions. Given the limited Cubesat injection infrastructure, transfer trajectories are contingent upon the modification of an initial condition of the injected or deployed orbit. Additionally, these transfers can be restricted by the selection or designs of Cubesat subsystems such as propulsion or communication. Nonetheless, many trajectory options can b e considered which have a wide range of transfer duration, fuel requirements, and final destinations. Our investigation of potential trajectories highlights several options including deployment from low Earth orbit (LEO) geostationary transfer orbits (GTO) and higher energy direct lunar transfer and the use of longer duration Earth-Moon dynamical systems. For missions with an intended lunar orbit, much of the design process is spent optimizing a ballistic capture while other science locations such as Sun-Earth libration or heliocentric orbits may simply require a reduced Delta-V imparted at a convenient location along the trajectory

    Transitions in Care in a Nationally Representative Sample of Older Americans with Dementia

    Get PDF
    OBJECTIVES: To describe transitions in care for older adults with dementia identified from a nationally representative cohort and to describe transition rates in those with more-severe levels of cognitive and functional impairment. DESIGN: Longitudinal cohort study. SETTING: Health and Retirement Study (HRS). PARTICIPANTS: HRS respondents aged 65 and older whose survey data were linked with Medicare claims from 1999 to 2008 (N = 16,186). MEASUREMENTS: Transitions in care between home, home with formal services, hospital, and nursing facility care; cognitive function; activities of daily living; and mortality. RESULTS: The 3,447 (21.3%) HRS subjects who were ever diagnosed with dementia experienced frequent transitions. Of subjects transitioning from a hospital stay, 52.2% returned home without home care services, and 33.8% transitioned to a nursing facility. Of subjects transitioning from a nursing facility, 59.2% transitioned to the hospital, and 25.3% returned home without services. There were 2,139 transitions to death, and 58.7% of HRS subjects with dementia died at home. Even in persons with moderate to severe dementia, multiple transitions in care were documented, including transitions from the hospital to home and back to the hospital. CONCLUSION: In this nationally representative sample of older adults, subjects diagnosed with dementia experience frequent transitions. Persons with dementia who are cared for at home and who transition back to home often have moderate to severe impairments in function and cognition

    Comorbid conditions explain the association between posttraumatic stress disorder and incident cardiovascular disease

    Get PDF
    Background Posttraumatic stress disorder ( PTSD ) is associated with risk of cardiovascular disease ( CVD ). Biopsychosocial factors associated with PTSD likely account for some or all of this association. We determined whether 1, or a combination of comorbid conditions explained the association between PTSD and incident CVD . Methods and Results Eligible patients used 1 of 5 Veterans Health Affairs medical centers distributed across the United States. Data were obtained from electronic health records. At index date, 2519 Veterans Health Affairs ( VA ) patients, 30 to 70 years of age, had PTSD diagnoses and 1659 did not. Patients had no CVD diagnoses for 12 months before index date. Patients could enter the cohort between 2008 and 2012 with follow-up until 2015. Age-adjusted Cox proportional hazard models were computed before and after adjusting for comorbidities. Patients were middle aged (mean=50.1 years, SD ±11.0), mostly male (87.0%), and 60% were white. The age-adjusted association between PTSD and incident CVD was significant (hazard ratio=1.41; 95% CI : 1.21-1.63). After adjustment for metabolic conditions, the association between PTSD and incident CVD was attenuated but remained significant (hazard ratio=1.23; 95% CI : 1.06-1.44). After additional adjustment for smoking, sleep disorder, substance use disorder, anxiety disorders, and depression, PTSD was not associated with incident CVD (hazard ratio=0.96; 95% CI : 0.81-1.15). Conclusions PTSD is not an independent risk factor for CVD . Physical and psychiatric conditions and smoking that co-occur with PTSD explain why this patient population has an increased risk of CVD . Careful monitoring may limit exposure to CVD risk factors and subsequent incident CVD

    Errors in self-reports of health services use: impact on alzheimer disease clinical trial designs

    Get PDF
    BACKGROUND: Most Alzheimer disease clinical trials that compare the use of health services rely on reports of caregivers. The goal of this study was to assess the accuracy of self-reports among older adults with Alzheimer disease and their caregiver proxy respondents. This issue is particularly relevant to Alzheimer disease clinical trials because inaccuracy can lead both to loss of power and increased bias in study outcomes. METHODS: We compared respondent accuracy in reporting any use and in reporting the frequency of use with actual utilization data as documented in a comprehensive database. We next simulated the impact of underreporting and overreporting on sample size estimates and treatment effect bias for clinical trials comparing utilization between experimental groups. RESULTS: Respondents self-reports have a poor level of accuracy with κ-values often below 0.5. Respondents tend to underreport use even for rare events such as hospitalizations and nursing home stays. In analyses simulating underreporting and overreporting of varying magnitude, we found that errors in self-reports can increase the required sample size by 15% to 30%. In addition, bias in the reported treatment effect ranged from 3% to 18% due to both underreporting and overreporting errors. CONCLUSIONS: Use of self-report data in clinical trials of Alzheimer disease treatments may inflate sample size needs. Even when adequate power is achieved by increasing sample size, reporting errors can result in a biased estimate of the true effect size of the intervention

    Using Patterns of Genetic Association to Elucidate Shared Genetic Etiologies Across Psychiatric Disorders

    Get PDF
    Twin studies indicate that latent genetic factors overlap across comorbid psychiatric disorders. In this study, we used a novel approach to elucidate shared genetic factors across psychiatric outcomes by clustering single nucleotide polymorphisms based on their genome-wide association patterns. We applied latent profile analysis (LPA) to p-values resulting from genome-wide association studies across three phenotypes: symptom counts of alcohol dependence (AD), antisocial personality disorder (ASP), and major depression (MD), using the European–American case-control genome-wide association study subsample of the collaborative study on the genetics of alcoholism (N = 1399). In the 3-class model, classes were characterized by overall low associations (85.6% of SNPs), relatively stronger association only with MD (6.8%), and stronger associations with AD and ASP but not with MD (7.6%), respectively. These results parallel the genetic factor structure identified in twin studies. The findings suggest that applying LPA to association results across multiple disorders may be a promising approach to identify the specific genetic etiologies underlying shared genetic variance

    How Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) Progresses: The Natural History of ME/CFS.

    Get PDF
    We propose a framework for understanding and interpreting the pathophysiology of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) that considers wider determinants of health and long-term temporal variation in pathophysiological features and disease phenotype throughout the natural history of the disease. As in other chronic diseases, ME/CFS evolves through different stages, from asymptomatic predisposition, progressing to a prodromal stage, and then to symptomatic disease. Disease incidence depends on genetic makeup and environment factors, the exposure to singular or repeated insults, and the nature of the host response. In people who develop ME/CFS, normal homeostatic processes in response to adverse insults may be replaced by aberrant responses leading to dysfunctional states. Thus, the predominantly neuro-immune manifestations, underlined by a hyper-metabolic state, that characterize early disease, may be followed by various processes leading to multi-systemic abnormalities and related symptoms. This abnormal state and the effects of a range of mediators such as products of oxidative and nitrosamine stress, may lead to progressive cell and metabolic dysfunction culminating in a hypometabolic state with low energy production. These processes do not seem to happen uniformly; although a spiraling of progressive inter-related and self-sustaining abnormalities may ensue, reversion to states of milder abnormalities is possible if the host is able to restate responses to improve homeostatic equilibrium. With time variation in disease presentation, no single ME/CFS case description, set of diagnostic criteria, or molecular feature is currently representative of all patients at different disease stages. While acknowledging its limitations due to the incomplete research evidence, we suggest the proposed framework may support future research design and health care interventions for people with ME/CFS

    Data-driven approach for highlighting priority areas for protection in marine areas beyond national jurisdiction

    Get PDF
    One of the aims of the United Nations (UN) negotiations on the conservation and sustainable use of marine biodiversity in areas beyond national jurisdiction (ABNJ) is to develop a legal process for the establishment of area-based management tools, including marine protected areas, in ABNJ. Here we use a conservation planning algorithm to integrate 55 global data layers on ABNJ species diversity, habitat heterogeneity, benthic features, productivity, and fishing as a means for highlighting priority regions in ABNJ to be considered for spatial protection. We also include information on forecasted species distributions under climate change. We found that parameterizing the planning algorithm to protect at least 30% of these key ABNJ conservation features, while avoiding areas of high fishing effort, yielded a solution that highlights 52,545,634 km2 (23.7%) of ABNJ as high priority regions for protection. Instructing the planning model to avoid ABNJ areas with high fishing effort resulted in relatively minor shifts in the planning solution, when compared to a separate model that did not consider fishing effort. Integrating information on climate change had a similarly minor influence on the planning solution, suggesting that climate-informed ABNJ protected areas may be able to protect biodiversity now and in the future. This globally standardized, data-driven process for identifying priority ABNJ regions for protection serves as a valuable complement to other expert-driven processes underway to highlight ecologically or biologically significant ABNJ regions. Both the outputs and methods exhibited in this analysis can additively inform UN decision-making concerning establishment of ABNJ protected areas

    Three-dimensional comparison of static and dynamic scapular motion tracking techniques

    Get PDF
    The final publication is available at Elsevier via http://dx.doi.org/10.1016/j.jelekin.2013.09.011. © 2014. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/The shoulder is complex and comprised of many moving parts. Accurately measuring shoulder rhythm is difficult. To classify shoulder rhythm and identify pathological movement, static measures have been the preferred method. However, dynamic measures are also used and can be less burdensome to obtain. The purpose of this paper was to determine how closely dynamic measures represent static measures using the same acromion marker cluster scapular tracking technique. Five shoulder angles were assessed for 24 participants using dynamic and static tracking techniques during humeral elevation in three planes (frontal, scapular, sagittal). ANOVAs were used to identify where significant differences existed for the factors of plane, elevation angle, and tracking technique (static, dynamic raising, dynamic lowering). All factors were significantly different for all shoulder angles (p<0.001), except for elevation plane in scapulothoracic protraction/retraction (p=0.955). Tracking techniques were influential (p<0.001), but the grouped mean differences fell below a clinically relevant 5° benchmark. There was large variation in mean differences of the techniques across individuals. While population averages are similar, individual static and dynamic shoulder assessments may be different. Caution should be taken when dynamic shoulder assessments are performed on individuals, as they may not reflect those obtained in static scapular motion tracking.Natural Sciences and Engineering Research Council || Canada Foundation for Innovatio
    • …
    corecore