5,127 research outputs found

    Instrumental variable methods to assess quality of care the marginal effects of process-of-care on blood pressure change and treatment costs

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    Background: Hypertension is poorly controlled. Team-based care and changes in the process of care have been proposed to address these quality problems. However, assessing care processes is difficult because they are often confounded even in randomized behavioral studies by unmeasured confounders based on discretion of health care providers. Objective: To evaluate the effects of process measures including number of counseling sessions about lifestyle modification and number of antihypertensive medications on blood pressure change and payer-perspective treatment costs. Methods: Data were obtained from two prospective, cluster randomized controlled clinical trials (Trial A and B) implementing physician-pharmacist collaborative interventions compared with usual care over six months in community-based medical offices in the Midwest. Multivariate linear regression models with both instrumental variable methods and as-treated methods were utilized. Instruments were indicators for trial and study arms. Models of blood pressure change and costs included both process measures, demographic variables, and clinical variables. Results: The analysis included 496 subjects. As-treated methods showed no significant associations between process and outcomes. The instruments used in the study were insufficient to simultaneously identify distinct process effects. However, the post-hoc instrumental variable models including one process measure at a time while controlling for the other process demonstrated significant associations between the processes and outcomes with estimates considerably larger than as-treated estimates. Conclusions: Instrumental variable methods with combined randomized behavioral studies may be useful to evaluate the effects of different care processes. However, substantial distinct process variation across studies is needed to fully capitalize on this approach. Instrumental variable methods focusing on individual processes provided larger and stronger outcome relationships than those found using as-treated methods which are subject to confounding

    Three approaches to the classification of inland wetlands

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    In the Dismal Swamp project, seasonal, color-infrared aerial photographs and LANDSAT digital data were interpreted for a detailed analysis of the vegetative communities in a large, highly altered wetland. In Western Tennessee, seasonal high altitude color-infrared aerial photographs provided the hydrologic and vegetative information needed to map inland wetlands, using a classification system developed for the Tennessee Valley Region. In Florida, color-infrared aerial photographs were analyzed to produce wetland maps using three existing classification systems to evaluate the information content and mappability of each system. The methods used in each of the three projects can be extended or modified for use in the mapping of inland wetlands in other parts of the United States

    Comparing Dominant and Non-Dominant Torque and Work Using Biodex 3 Isokinetic Protocol for Knee Flexors and Extensors

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    INTRODUCTION. There is often a misconception when looking at comparing dominant and non-dominant limbs of any sort. Although there will be a lack of control in non-dominant limbs compared to dominant, the amount of torque and power associated with each limb may be equal; even so, there may be an instance of bilateral deficit, where even though the dominant limb may be used to do work on a specific limb, the non-dominant limb may still receive strength benefits. PURPOSE. The main purpose of this study is to directly relate ability (torque and total work) in both dominant and non-dominate limbs with a focus on knee flexion and extension. METHODS. Participants: Four (N = 4; 4 males, 0 females) volunteers were utilized for this study. The average age of the participants were 24.5 + 1.73 years old, average height was 71.75 + 3.20” (inches or 182.245 centimeters), and average weight was 183.26 + 45.78 pounds (83.3 kilograms). Methodology: Upon arriving to the lab, each participant was measured for height (recorded in inches) and weight (recorded in kilograms), as well as age was recorded (years). Each participant was added into the system when they attempted to perform the protocol. The protocol utilized isokinetic concentric/concentric contractions on the knee for three separate speeds or sets (30/s, 60/s, and 90/s); each set included 5 repetitions. Upon completion of each set (5 repetitions) the participant would be allowed 10 seconds of rest. Following the same protocol, all participants would complete the test using their non-dominate leg. RESULTS. The value and percent difference associated with dominant and non-dominant extension (both torque and work) were rather large. As seen in the percent difference section, the value of each percent difference were at least 7.83% (min) and as high as 27.43% (max). There was also a noticeable percent difference associated with 90/s in flexion for both torque and work between dominant and non-dominant with values at torque = 19.97% and work = 16.23%. DISCUSSION. This study may help provide insight into how dominant and non-dominant limbs may be trained and how they may be equal even without training. This may be untrue due to many variables, but this study has allowed a certain insight into how dominant and non-dominant limbs may be equal in gross motor movements. Results that find non-dominant to dominant differences may be errors due the tester and/or the participant; it may be due to the participant because of situational awareness, they may learn the protocol and movements with one leg and adjust using the other

    77^{77}Se and 63^{63}Cu NMR studies of the electronic correlations in Cux_xTiSe2_2 (x=0.05,0.07x=0.05, 0.07)

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    We report 77^{77}Se and 63^{63}Cu nuclear magnetic resonance (NMR) investigation on the charge-density-wave (CDW) superconductor Cux_xTiSe2_2 (x=0.05x=0.05 and 0.07). At high magnetic fields where superconductivity is suppressed, the temperature dependence of 77^{77}Se and 63^{63}Cu spin-lattice relaxation rates 1/T_{1}followalinearrelation.Theslopeof follow a linear relation. The slope of ^{77}1/T_{1}$ vs \emph{T} increases with the Cu doping. This can be described by a modified Korringa relation which suggests the significance of electronic correlations and the Se 4\emph{p}- and Ti 3\emph{d}-band contribution to the density of states at the Fermi level in the studied compounds.Comment: Revised manuscript. Submitted to Journal of Physics: Condensed Matte

    The antibacterial activity of Australian Leptospermum honey correlates with methylglyoxal levels

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    © 2016 Cokcetin et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Most commercially available therapeutic honey is derived from flowering Leptospermum scoparium (manuka) plants from New Zealand. Australia has more than 80 Leptospermum species, and limited research to date has found at least some produce honey with high nonperoxide antibacterial activity (NPA) similar to New Zealand manuka, suggesting Australia may have a ready supply of medical-grade honey. The activity of manuka honey is largely due to the presence of methylglyoxal (MGO), which is produced non-enzymatically from dihydroxyacetone (DHA) present in manuka nectar. The aims of the current study were to chemically quantify the compounds contributing to antibacterial activity in a collection of Australian Leptospermum honeys, to assess the relationship between MGO and NPA in these samples, and to determine whether NPA changes during honey storage. Eighty different Leptospermum honey samples were analysed, and therapeutically useful NPA was seen in samples derived from species including L. liversidgei and L. polygalifolium. Exceptionally high levels of up to 1100 mg/kg MGO were present in L. polygalifolium honey samples sourced from the Northern Rivers region in NSW and Byfield, QLD, with considerable diversity among samples. There was a strong positive relationship between NPA and MGO concentration, and DHA was present in all of the active honey samples, indicating a potential for ongoing conversion to MGO. NPA was stable, with most samples showing little change following seven years of storage in the dark at 4°C. This study demonstrates the potential for Australian Leptospermum honey as a wound care product, and argues for an extension of this analysis to other Leptospermum species

    The 4-Hour Cairns Sepsis Model: a novel approach to predicting sepsis mortality at intensive care unit admission

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    Background: Sepsis commonly causes intensive care unit (ICU) mortality, yet early identification of adults with sepsis at risk of dying in the ICU remains a challenge. Objective: The aim of the study was to derive a mortality prediction model (MPM) to assist ICU clinicians and researchers as a clinical decision support tool for adults with sepsis within 4 h of ICU admission. Methods: A cohort study was performed using 500 consecutive admissions between 2014 and 2018 to an Australian tertiary ICU, who were aged ≥18 years and had sepsis. A total of 106 independent variables were assessed against ICU episode-of-care mortality. Multivariable backward stepwise logistic regression derived an MPM, which was assessed on discrimination, calibration, fit, sensitivity, specificity, and predictive values and bootstrapped. Results: The average cohort age was 58 years, the Acute Physiology and Chronic Health Evaluation III-j severity score was 72, and the case fatality rate was 12%. The 4-Hour Cairns Sepsis Model (CSM-4) consists of age, history of renal disease, number of vasopressors, Glasgow Coma Scale, lactate, bicarbonate, aspartate aminotransferase, lactate dehydrogenase, albumin, and magnesium with an area under the receiver operating characteristic curve of 0.90 (95% confidence interval = 0.84–0.95, p < 0.00001), a Nagelkerke R2 of 0.51, specificity of 0.94, a negative predictive value of 0.98, and almost identical odds ratios during bootstrapping. The CSM-4 outperformed existing MPMs tested on our data set. The CSM-4 also performed similar to existing MPMs in their derivation papers whilst using fewer, routinely collected, and inexpensive variables. Conclusions: The CSM-4 is a newly derived MPM for adults with sepsis at ICU admission. It displays excellent discrimination, calibration, fit, specificity, negative predictive value, and bootstrapping values whilst being easy to use and inexpensive. External validation is required

    The applicability of commonly used predictive scoring systems in Indigenous Australians with sepsis: An observational study

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    Background Indigenous Australians suffer a disproportionate burden of sepsis, however, the performance of scoring systems that predict mortality in Indigenous patients with critical illness is incompletely defined. Materials and methods The study was performed at an Australian tertiary-referral hospital between January 2014 and June 2017, and enrolled consecutive Indigenous and non-Indigenous adults admitted to ICU with sepsis. The ability of the ANZROD, APACHE-II, APACHE-III, SAPS-II, SOFA and qSOFA scores to predict death before ICU discharge in the two populations was compared. Results There were 442 individuals enrolled in the study, 145 (33%) identified as Indigenous. Indigenous patients were younger than non-Indigenous patients (median (interquartile range (IQR) 53 (43-60) versus 65 (52-73) years, p = 0.0001) and comorbidity was more common (118/145 (81%) versus 204/297 (69%), p = 0.005). Comorbidities that were more common in the Indigenous patients included diabetes mellitus (84/145 (58%) versus 67/297 (23%), p<0.0001), renal disease (56/145 (39%) versus 29/297 (10%), p<0.0001) and cardiovascular disease (58/145 (40%) versus 83/297 (28%), p = 0.01). The use of supportive care (including vasopressors, mechanical ventilation and renal replacement therapy) was similar in Indigenous and non-Indigenous patients, and the two populations had an overall case-fatality rate that was comparable (17/145 (12%) and 38/297 (13%) (p = 0.75)), although Indigenous patients died at a younger age (median (IQR): 54 (50-60) versus 70 (61-76) years, p = 0.0001). There was no significant difference in the ability of any the scores to predict mortality in the two populations. Conclusions Although the crude case-fatality rates of Indigenous and non-Indigenous Australians admitted to ICU with sepsis is comparable, Indigenous patients die at a much younger age. Despite this, the ability of commonly used scoring systems to predict outcome in Indigenous Australians is similar to that of non-Indigenous Australians, supporting their use in ICUs with a significant Indigenous patient population and in clinical trials that enrol Indigenous Australians

    The Effects of a Pre-Workout Energy Drink on Measures of Physical Performance

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    The purpose of this study was to investigate the effects of a pre-workout commercial energy drink on parameters of exercise performance, including anaerobic power, muscular endurance, speed, and reaction time. This study used a randomized, double blind, placebo controlled, parallel design. Participants visited the laboratory on two different occasions. On the first visit, participants were assessed for anaerobic power (via a vertical jump test), muscular endurance, reaction time, reactive sprint test, and aerobic power (via a 1.5 mile run). On the second visit, participants were randomly assigned to ingest four ounces of the energy drink beverage or a similar-tasting placebo beverage 30-minutes prior to engaging in these same physical performance tests. The energy drink treatment had no effect on anaerobic power (vertical jump), reaction time, reactive sprint test, or aerobic power. For the push-up to fatigue test, a significant difference (p = 0.014) was observed with the energy drink treatment enhancing performance by 12% as compared to the placebo treatment (improvement of ~ 4%). For the sit-up to fatigue test, a non-significant difference (p = 0.075) was observed with the energy drink treatment resulting in an enhancement of performance by ~13% as compared to no improvement for the placebo treatment. In light of these findings, individuals whose upper-body muscular endurance performance is part of their physical fitness assessment program may benefit from pre-workout energy drink consumption. In contrast, individuals needing to demonstrate anaerobic/aerobic power, or reactive abilities should not expect an improvement in performance from pre-workout energy drink consumption
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