16,694 research outputs found

    Functional Assessment of Heart Failure Patients

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    Heart failure (HF) is the condition characterized by the inability of the heart to pump sufficient blood to meet the demands of the body. It has been well established that both the prevalence and incidence of HF is increasing.1 There are 2 primary types of HF, categorized by ejection fraction: Reduced ejection fraction and preserved ejection fraction.2 Additionally, HF is commonly classified into stages from mild to severe using a symptom-based scale related to functional limitations. One of the hallmark features of HF is exercise intolerance, which is accompanied by symptoms of fatigue and shortness of breath.3 As the disease progresses, patients experience a downward spiral as these symptoms typically result in reduced physical activity, which leads to progressively worsening exercise intolerance. Typically, patients with HF are faced with what can be termed a functional disability. Often, their reduced functional abilities restrict or may even prevent them from performing occupational tasks, which may result in loss of work. Additionally, it is well known that patients with HF experience impairment in the ability to carry out activities of daily living and suffer from reduced quality of life. The objective of this paper was to provide an overview of assessments of functional ability of patients with HF. Two categories of assessment are reviewed: Cardiovascular function and muscular function. The review includes procedural guidance on how to administer the assessments and information related to the advantages and disadvantages of each method. Because both HF types (reduced ejection fraction and preserved ejection fraction) are characterized by exercise intolerance, the procedures can be used effectively with either type of HF

    Corporate Social Responsibility and Earnings Reporting

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    Despite increasing interests on corporate social responsibility (CSR) activities among managers, the relationship between CSR and firm value through earnings reporting quality is still unclear. Absence of a strong positive effect of CSR on firm value has led researchers to believe that CSR is a res ult of a principal-agent issue between shareholders and managers. This study argues CSR represents a corporate culture that influences how a corporation reports its earnings. CSR influ ences earnings reporting ·instead ofearnings reporting drives CSR to delude shareholders. CSR induces better earnings reporting quality, therefore, CSR has an indirect but positive effect on firm value

    The matching law

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    This article introduces the quantitative analysis of choice behavior by describing a number of equations developed over the years to describe the relation between the allocation of behavior under concurrent schedules of reinforcement and the consequences received for alternative responses. Direct proportionality between rate of responding and rate of reinforcement was observed in early studies, suggesting that behavioral output matched environmental input in a mathematical sense. This relation is termed "strict matching," and the equation that describes it is referred to as "the matching law." Later data showed systematic departures from strict matching, and a generalized version of the matching equation is now used to describe such data. This equation, referred to as "the generalized matching equation," also describes data that follow strict matching. It has become convention to refer to either of these equations as "the matching law." Empirical support for the matching law is briefly summarized, as is the applied and practical significance of matching analyses

    Taming the Pion Cloud of the Nucleon

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    We present a light-front determination of the pionic contribution to the nucleon self-energy, Σπ\Sigma_\pi, to second-order in pion-baryon coupling constants that allows the pion-nucleon vertex function to be treated in a model-independent manner constrained by experiment. The pion mass μ\mu dependence of Σπ\Sigma_\pi is consistent with chiral perturbation theory results for small values of μ\mu and is also linearly dependent on μ\mu for larger values, in accord with the results of lattice QCD calculations. The derivative of Σπ\Sigma_\pi with respect to μ2\mu^2 yields the dominant contribution to the pion content, which is consistent with the dˉuˉ\bar{d}-\bar{u} difference observed experimentally in the violation of the Gottfried sum rule.Comment: 11 pages, 3 figure

    The pressure-amorphized state in zirconium tungstate: a precursor to decomposition

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    In contrast to widely accepted view that pressure-induced amorphization arises due to kinetic hindrance of equilibrium phase transitions, here we provide evidence that the metastable pressure-amorphized state in zirconium tungstate is a precursor to decomposition of the compound into a mixture of simple oxides. This is from the volume collapse ΔV across amorphization, which is obtained for the first time by measuring linear dimensions of irreversibly amorphized samples during their recovery to the original cubic phase upon isochronal annealing up to 1000 K. The anomalously large ΔV of 25.7 ± 1.2% being the same as that expected for the decomposition indicates that this amorphous state is probably a precursor to kinetically hindered decomposition. A P–T diagram of the compound is also proposed

    Variability of Objectively Measured Sedentary Behavior

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    The primary purpose of this study was to evaluate variability of sedentary behavior (SB) throughout a 7-d measurement period and to determine if G7 d of SB measurement would be comparable with the typical 7-d measurement period. Methods: Retrospective data from Ball State University_s Clinical Exercise Physiology Laboratory on 293 participants (99 men, 55 T 14 yr, body mass index = 29 T 5 kgImj2; 194 women, 51 T 12 yr, body mass index = 27 T 7 kgImj2) with seven consecutive days of data collected with ActiGraph accelerometers were analyzed (ActiGraph, Fort Walton Beach, FL). Time spent in SB (either G100 counts per minute or G150 counts per minute) and breaks in SB were compared between days and by sex using a two-way repeated-measures ANOVA. Stepwise regression was performed to determine if G7 d of SB measurement were comparable with the 7-d method, using an adjusted R2 of Q0.9 as a criterion for equivalence. Results: There were no differences in daily time spent in SB between the 7 d for all participants. However, there was a significant interaction between sex and days, with women spending less time in SB on both Saturdays and Sundays than men when using the 100 counts per minute cut-point. Stepwise regression showed using any 4 d would be comparable with a 7-d measurement (R2 9 0.90). Conclusions: When assessed over a 7-d measurement period, SB appears to be very stable from day to day, although there may be some small differences in time spent in SB and breaks in SB between men and women, particularly on weekend days. The stepwise regression analysis suggests that a measurement period as short as 4 d could provide comparable data (91% of variance) with a 1-wk assessment. Shorter assessment periods would reduce both researcher and subject burden in data collection

    Peak Ventilation Reference Standards from Exercise Testing: From the FRIEND Registry

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    Peak Ventilation Reference Standards from Exercise Testing: From the FRIEND Registry. Med. Sci. Sports Exerc., Vol. 50, No. 12, pp. 2603–2608, 2018. Purpose: Cardiopulmonary exercise testing (CPX) provides valuable clinical information, including peak ventilation (V˙ Epeak), which has been shown to have diagnostic and prognostic value in the assessment of patients with underlying pulmonary disease. This report provides reference standards for V˙ Epeak derived from CPX on treadmills in apparently healthy individuals. Methods: Nine laboratories in the United States experienced in CPX administration with established quality control procedures contributed to the Fitness Registry and the Importance of Exercise National Database from 2014 to 2017. Data from 5232 maximal exercise tests from men and women without cardiovascular or pulmonary disease were used to create percentiles ofV˙ Epeak for both men and women by decade between 20 and 79 yr. Additionally, prediction equations were developed for V˙ Epeak using descriptive information. Results: V˙ Epeak was found to be significantly different between men and women and across age groups (P G 0.05). The rate of decline in V˙ Epeak was 8.0% per decade for both men and women. A stepwise regression model of 70% of the sample revealed that sex, age, and height were significant predictors ofV˙ Epeak. The equation was cross-validated with data from the remaining 30% of the sample with a final equation developed from the full sample (r = 0.73). Additionally, a linear regression model revealed forced expiratory volume in 1 s significantly predicted V˙ Epeak (r = 0.73). Conclusions: Reference standards were developed for V˙ Epeak for the United States population. Cardiopulmonary exercise testing laboratories will be able to provide interpretation of V˙ Epeak from these age and sex-specific percentile reference values or alternatively can use these nonexercise prediction equations incorporating sex, age, and height or with a single predictor of forced expiratory volume in 1 s
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