Mack C. Shelley

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PROBLEM A homogeneous perception of safety is important for the achievement of a strong safety culture; however, employees may differ in their safety perceptions, depending on their position and/or hierarchical level within the organization. Moreover, there is limited information on the antecedents of safety culture. This study examines how safety training,(More)
In the current study, the Distance Education Student Satisfaction Model, estimated as a structural equation model, is proposed to understand better what predicts student satisfaction from online learning environments. In the present study, the following variables are employed based on the Technology Acceptance Model (TAM) (Davis, Bagozzi, & Warshaw, 1989)(More)
BACKGROUND Cognitive impairments in Parkinson disease (PD) manifest as deficits in speed of processing, working memory, and executive function and attention abilities. The gait impairment in PD is well documented to include reduced speed, shortened step lengths, and increased step-to-step variability. However, there is a paucity of research examining the(More)
OBJECTIVE To examine the relationship between Timed Up and Go (TUG) performance, verbal executive function (EF) performance, and quality-of-life (QOL) measures in Parkinson's disease (PD). DESIGN Cross-sectional. SETTING Sixteen movement disorder centers from across the United States. PARTICIPANTS Patients with PD (N=1964). INTERVENTIONS Not(More)
This cross-sectional study determined the prevalence of nephrolithiasis and common cardiovascular disease (CVD) risk factors in a law enforcement officer (LEO) cohort and evaluated the relationship of nephrolithiasis with several CVD risk factors, including the possible effect of ethnicity. Self reported nephrolithiasis and CVD risk factors among currently(More)
It is unclear to what extent law enforcement officers (LEOs) experience increased prevalence of cardiovascular disease (CVD; defined as coronary heart disease, myocardial infarction, angina, or stroke) and, if so, whether perceived stress affects this relationship. First, self-reported CVD risk factors among currently employed male LEOs from 9 states (n =(More)
This study examined the measurement of depressive symptoms among American Indian adolescents as assessed by the Center for Epidemiologic Studies Depression Scale (CES-D), Youth Self Report (YSR), and the Tri-Ethnic Center's for Prevention Research Depression Scale (TEDS). This analysis demonstrated that the TEDS had good internal consistency, demonstrated(More)
Lowery, RP, Joy, JM, Rathmacher, JA, Baier, SM, Fuller, JC Jr, Shelley, MC II, Jäger, R, Purpura, M, Wilson, SMC, and Wilson, JM. Interaction of beta-hydroxy-beta-methylbutyrate free acid and adenosine triphosphate on muscle mass, strength, and power in resistance trained individuals. J Strength Cond Res 30(7): 1843-1854, 2016-Adenosine-5'-triphosphate(More)
The authors studied contributors to stress among undergraduate residence hall students at a midwestern, land grant university using a 76-item survey consisting of personal, health, academic, and environmental questions and 1 qualitative question asking what thing stressed them the most. Of 964 students selected at random, 462 (48%) responded to the survey.(More)
An integrated series of courses on embedded systems has been developed at Iowa State University, Ames, spanning early undergraduate to graduate levels. The newest course in the series is CPRE 488: Embedded Systems Design, an advanced undergraduate course that fills a gap in the curriculum by providing system-level design experiences and incorporating new(More)