Spatial and temporal analysis of radial growth in an Appalachian watershed

This dendrochronological study used dated and measured tree-ring data to examine relationships between radial growth and climate for four hard wood species, yellow-poplar, northern red oak, chestnut oak and red maple, growing on contrasting topographic aspects of a watershed in north-central West Virginia.;The study showed that all species except northern red oak showed significant differences in growth between the mesic and xeric aspects. Where significant differences were found all except chestnut oak exhibited higher growth rates at the mesic aspect.;Yellow-poplar showed a sharp decline in growth from late 1950\u27s to late 1960\u27s, which was evidently caused by several years of below average precipitation. The more conservative species, red oak, chestnut oak and red maple, showed a mild response to the drought compared to yellow-poplar which experienced 30--40% less growth relative to its peak growth in the late 1950\u27s.;All four species exhibited sensitivity to climate, especially to growing season precipitation. Sensitivity to climate followed the sequence yellow-poplar \u3e northern red oak \u3e chestnut oak \u3e red maple.;Regarding the interaction of aspect and climatic sensitivity, yellow-poplar displayed greater sensitivity to climate at the xeric site while the oaks showed little evidence of an aspect-related interaction with climate. For red maple, aspect did interact with climatic sensitivity, although this species showed an overall insensitivity to climate. The results of this study are logical in terms of the ecological strategies of the species; yellow-poplar is widely known to be site specific and exploitive, whereas oaks and maples are more conservative

Analysis of Airborne Betula Pollen in Finland; a 31-Year Perspective

In this 31-year retrospective study, we examined the influence of meteorology on airborne Betula spp. (birch) pollen concentrations in Turku, Finland. The seasonal incidence of airborne birch pollen in Turku occurred over a brief period each year during spring (April 30 – May 31). Mean peak concentrations were restricted to May (May 5 to 13). Statistically significant increases in the annual accumulated birch pollen sum and daily maximum values were observed over the study period. Birch pollen counts collected in April were retrospectively shown to increase over the duration of the study. Increases in April temperature values were also significantly associated with the earlier onset of the birch pollen season. Furthermore, the number of days where daily birch pollen concentrations exceeded 10 and 1,000 grains/m3 also increased throughout the study period. These data demonstrate that increases in temperature, especially during months preceding the onset of the birch pollen season, favor preseason phenological development and pollen dispersal. Birch pollen derived from other geographical locations may also contribute to the aerospora of Turku, Finland. To date, the public health burden associated with personal exposure to elevated birch pollen loads remains unclear and is the focus of future epidemiological research

Association between Depressive Symptoms and Metabolic Syndrome in Police Officers: Results from Two Cross-Sectional Studies

Policing is one of the most dangerous and stressful occupations and such stress can have deleterious effects on health. The purpose of this study was to examine the association between depressive symptoms and metabolic syndrome (MetSyn) in male and female police officers from two study populations, Buffalo, NY and Spokane, WA. Depressive symptoms were measured using the Center for Epidemiologic Studies-Depression (CES-D) scale. MetSyn was defined using the 2005 AHA/NHBLI guidelines. Analysis of covariance was used to describe differences in number of MetSyn components across depressive symptom categories. The number of MetSyn components increased significantly across categories of CES-D for Spokane men only (p-trend = 0.003). For each 5-unit increase in CES-D score, odds increased by 47.6% for having hypertriglyceridemia, by 51.8% for having hypertension, and by 56.7% for having glucose intolerance. Exploring this association is important since both are predictors of future chronic health problems and the results could be helpful in developing future gender-specific prevention and intervention efforts among police officers

Associations of objectively measured and self-reported sleep duration with carotid artery intima media thickness among police officers

BACKGROUND: We aimed to examine the association of objectively measured and self-reported sleep duration with carotid artery intima media thickness (IMT) among 257 police officers, a group at high risk for cardiovascular disease (CVD). METHODS: Sleep duration was estimated using actigraphic data and through self-reports. The mean maximum IMT was the average of the largest 12 values scanned bilaterally from three angles of the near and far wall of the common carotid, bulb, and internal carotid artery. Linear and quadratic regression models were used to assess the association of sleep duration with IMT. RESULTS: Officers who had fewer than 5 or 8 hr or more of objectively measured sleep duration had significantly higher maximum IMT values, independent of age. Self-reported sleep duration was not associated with either IMT measure. CONCLUSION: Attainment of sufficient sleep duration may be considered as a possible strategy for atherosclerosis prevention among police officers

Parameter Estimation of Nonlinear Models in Forestry.

Partial derivatives of the negative exponential, monomolecular, Mitcherlich, Gompertz, logistic, Chapman-Richards, von Bertalanffy, Weibull and the Richard’s nonlinear growth models are presented. The application of these partial derivatives in estimating the model parameters is illustrated. The parameters are estimated using the Marquardt iterative method of nonlinear regression relating top height to age of Norway spruce (Picea abies L.) from the Bowmont Norway Spruce Thinning Experiment. Formulas that provide good initial values of the parameters are specified. Clear definitions of the parameters of the nonlinear models in the context of the system being modelled are found to be critically important in the process of parameter estimation.Author has checked copyrightDG 22/11/1

Fatigue and short-term unplanned absences among police officers

Dawson, D ORCiD: 0000-0001-7385-5630Purpose – The purpose of this paper is to assess whether shift work, sleep loss and fatigue are related to shortterm unplanned absences in policing. Design/methodology/approach – N 5 367 police officers from the Buffalo Police Department were studied. Day-by-day work and sick leave data were obtained from the payroll. Absenteeism was defined as taking a single sick day on a regularly scheduled workday. Biomathematical models of fatigue (BMMF) predicted officers’ sleep–wake behaviors and on-duty fatigue and sleepiness. Prior sleep, fatigue and sleepiness were tested as predictors of absenteeism during the next shift. Findings – A total of 513,666 shifts and 4,868 cases of absenteeism were studied. The odds of absenteeism increased as on-duty fatigue and sleepiness increased and prior sleep decreased. This was particularly evident for swing shift officers and night shift officers who were predicted by BMMF to obtain less sleep and have greater fatigue and sleepiness than day shift officers. The odds of absenteeism were higher for female officers than male officers; this finding was not due to a differential response to sleep loss, fatigue or sleepiness

Generalizability of a biomathematical model of fatigue’s sleep predictions

Dawson, D ORCiD: 0000-0001-7385-5630Introduction: Biomathematical models of fatigue (BMMF) predict fatigue during a work-rest schedule on the basis of sleep-wake histories. In the absence of actual sleep-wake histories, sleep-wake histories are predicted directly from work-rest schedules. The predicted sleep-wake histories are then used to predict fatigue. It remains to be determined whether workers organize their sleep similarly across operations and thus whether sleep predictions generalize. Methods: Officers (n = 173) enrolled in the Buffalo Cardio-Metabolic Occupational Police Stress study were studied. Officers’ sleep-wake behaviors were measured using wrist-actigraphy and predicted using a BMMF (FAID Quantum) parameterized in aviation and rail. Sleepiness (i.e. Karolinska Sleepiness Scale (KSS) ratings) was predicted using actual and predicted sleep-wake data. Data were analyzed using sensitivity analyses. Results: During officers’ 16.0 ± 1.9 days of study participation, they worked 8.6 ± 3.1 shifts and primarily worked day shifts and afternoon shifts. Across shifts, 7.0 h ± 1.9 h of actual sleep were obtained in the prior 24 h and associated peak KSS ratings were 5.7 ± 1.3. Across shifts, 7.2 h ± 1.1 h of sleep were predicted in the prior 24 h and associated peak KSS ratings were 5.5 ± 1.2. The minute-by-minute predicted and actual sleep-wake data demonstrated high sensitivity (80.4%). However, sleep was observed at all hours-of-the-day, but sleep was rarely predicted during the daytime hours. Discussion: The sleep-wake behaviors predicted by a BMMF parameterized in aviation and rail demonstrated high sensitivity with police officers’ actual sleep-wake behaviors. Additional night shift data are needed to conclude whether BMMF sleep predictions generalize across operations. © 2020, © 2020 Taylor & Francis Group, LLC

Work Hours and Cognitive Function: The Multi-Ethnic Study of Atherosclerosis

Cognitive impairment is a public health burden. Our objective was to investigate associations between work hours and cognitive function. Multi-Ethnic Study of Atherosclerosis (MESA) participants (n = 2,497; 50.7% men; age range 44–84 years) reported hours per week worked in all jobs in Exams 1 (2000–2002), 2 (2002–2004), 3 (2004–2005), and 5 (2010–2011). Cognitive function was assessed (Exam 5) using the Cognitive Abilities Screening Instrument (version 2), a measure of global cognitive functioning; the Digit Symbol Coding, a measure of processing speed; and the Digit Span test, a measure of attention and working memory. We used a prospective approach and linear regression to assess associations for every 10 hours of work. Among all participants, associations of hours worked with cognitive function of any type were not statistically significant. In occupation-stratified analyses (interaction p = 0.051), longer work hours were associated with poorer global cognitive function among Sales/Office and blue-collar workers, after adjustment for age, sex, physical activity, body mass index, race/ethnicity, educational level, annual income, history of heart attack, diabetes, apolipoprotein E-epsilon 4 allele (ApoE4) status, birth-place, number of years in the United States, language spoken at MESA Exam 1, and work hours at Exam 5 (β = –0.55, 95% CI = –0.99, –0.09) and (β = –0.80, –1.51, –0.09), respectively. In occupation-stratified analyses (interaction p = 0.040), we also observed an inverse association with processing speed among blue-collar workers (adjusted β = –0.80, –1.52, –0.07). Sex, race/ethnicity, and ApoE4 did not significantly modify associations between work hours and cognitive function. Weak inverse associations were observed between work hours and cognitive function among Sales/Office and blue-collar workers