Vectors of infectious diseases are generally thought to be regulated by abiotic conditions such as climate or the availability of specific hosts or habitats. In this study we tested whether ...blacklegged ticks, the vectors of Lyme disease, granulocytic anaplasmosis and babesiosis can be regulated by the species of vertebrate hosts on which they obligately feed. By subjecting field-caught hosts to parasitism by larval blacklegged ticks, we found that some host species (e.g. opossums, squirrels) that are abundantly parasitized in nature kill 83-96% of the ticks that attempt to attach and feed, while other species are more permissive of tick feeding. Given natural tick burdens we document on these hosts, we show that some hosts can kill thousands of ticks per hectare. These results indicate that the abundance of tick vectors can be regulated by the identity of the hosts upon which these vectors feed. By simulating the removal of hosts from intact communities using empirical models, we show that the loss of biodiversity may exacerbate disease risk by increasing both vector numbers and vector infection rates with a zoonotic pathogen.
The development of fracture mechanics test methods for the determination of delamination resistance or fracture toughness of fiber-reinforced, polymer–matrix composites is an active area of research. ...The emphasis in this review is on standardisation of test methods. Recent developments leading towards new standardized test procedures will be presented, complementing and updating earlier reviews.
Psychosocial work stress has been linked to higher risk of type 2 diabetes (T2DM), with the effect being consistently higher among women than men. Also, work stress has been linked to prospective ...weight gain among obese men but weight loss among lean men. Here, we aimed to examine the interaction between work stress and obesity in relation to T2DM risk in a gender‐specific manner. We studied 5,568 white middle‐aged men and women in the Whitehall II study, who were free from diabetes at analysis baseline (1993). After 1993, diabetes was ascertained at six consecutive phases by an oral glucose tolerance test supplemented by self‐reports. Cox regression analysis was used to assess the association between job strain (high job demands/low job control) and 18‐year incident T2DM stratifying by BMI (BMI <30 kg/m2 vs. BMI ≥30 kg/m2). Overall, work stress was associated with incident T2DM among women (hazard ratio (HR) 1.41: 95% confidence intervals: 1.02; 1.95) but not among men (HR 0.87: 95% confidence interval 0.69; 1.11) (PINTERACTION = 0.017). Among men, work stress was associated with a lower risk of T2DM in nonobese (HR 0.70: 0.53; 0.93) but not in obese individuals (PINTERACTION = 0.17). Among women, work stress was associated with higher risk of T2DM in the obese (HR 2.01: 1.06; 3.92) but not in the nonobese (PINTERACTION = 0.005). Gender and body weight status play a critical role in determining the direction of the association between psychosocial stress and T2DM. The potential effect‐modifying role of gender and obesity should not be ignored by future studies looking at stress‐disease associations.
Aims
The first reports of declining hospital admissions for major cardiovascular emergencies during the COVID-19 pandemic attracted public attention. However, systematic evidence on this subject is ...sparse. We aimed to investigate the rate of emergent hospital admissions, subsequent invasive treatments and comorbidities during the COVID-19 pandemic in Germany.
Methods and results
This was a retrospective analysis of health insurance claims data from the second largest insurance fund in Germany, BARMER. Patients hospitalized for acute myocardial infarction, acute limb ischemia, aortic rupture, stroke or transient ischemic attack (TIA) between January 1, 2019, and May 31, 2020, were included. Admission rates per 100,000 insured, invasive treatments and comorbidities were compared from January–May 2019 (pre-COVID) to January–May 2020 (COVID). A total of 115,720 hospitalizations were included in the current analysis (51.3% females, mean age 72.9 years). Monthly admission rates declined from 78.6/100,000 insured (pre-COVID) to 70.6/100,000 (COVID). The lowest admission rate was observed in April 2020 (61.6/100,000). Administration rates for ST-segment elevation myocardial infarction (7.3–6.6), non-ST-segment elevation myocardial infarction (16.8–14.6), acute limb ischemia (5.1–4.6), stroke (35.0–32.5) and TIA (13.7–11.9) decreased from pre-COVID to COVID. Baseline comorbidities and the percentage of these patients treated with interventional or open-surgical procedures remained similar over time across all entities. In-hospital mortality in hospitalizations for stroke increased from pre-COVID to COVID (8.5–9.8%).
Conclusions
Admission rates for cardiovascular and cerebrovascular emergencies declined during the pandemic in Germany, while patients’ comorbidities and treatment allocations remained unchanged. Further investigation is warranted to identify underlying reasons and potential implications on patients’ outcomes.
Graphic abstract
Novel methods of data analysis were used to interpret codling moth (Cydia pomonella) catch data from central-trap, multiple-release experiments using a standard codlemone-baited monitoring trap in ...commercial apple orchards not under mating disruption. The main objectives were to determine consistency and reliability for measures of: 1) the trapping radius, composed of the trap's behaviorally effective plume reach and the maximum dispersive distance of a responder population; and 2) the proportion of the population present in the trapping area that is caught. Two moth release designs were used: 1) moth releases at regular intervals in the four cardinal directions, and 2) evenly distributed moth releases across entire approximately 18-ha orchard blocks using both high and low codling moth populations. For both release designs, at high populations, the mean proportion catch was 0.01, and for the even release of low populations, that value was approximately 0.02. Mean maximum dispersive distance for released codling moth males was approximately 260 m. Behaviorally effective plume reach for the standard codling moth trap was < 5 m, and total trapping area for a single trap was approximately 21 ha. These estimates were consistent across three growing seasons and are supported by extraordinarily high replication for this type of field experiment. Knowing the trapping area and mean proportion caught, catch number per single monitoring trap can be translated into absolute pest density using the equation: males per trapping area = catch per trapping area/proportion caught. Thus, catches of 1, 3, 10, and 30 codling moth males per trap translate to approximately 5, 14, 48, and 143 males/ha, respectively, and reflect equal densities of females, because the codling moth sex ratio is 1:1. Combined with life-table data on codling moth fecundity and mortality, along with data on crop yield per trapping area, this fundamental knowledge of how to interpret catch numbers will enable pest managers to make considerably more precise projections of damage and therefore more precise and reliable decisions on whether insecticide applications are justified. The principles and methods established here for estimating absolute codling moth density may be broadly applicable to pests generally and thereby could set a new standard for integrated pest management decisions based on trapping.
Endothelial dysfunction develops early and has been shown to predict the development of clinical complications of atherosclerosis. However, the relationship between early endothelial dysfunction and ...the progression of arterial disease in the general population is unknown. We investigated endothelial dysfunction, risk factors, and progression of carotid intima-media thickness (cIMT) in late-middle-aged individuals at low to intermediate cardiovascular risk in a prospective study between 1997 and 2005.
Brachial artery flow-mediated dilatation and cIMT were measured in 213 nonsmoking British civil servants recruited from a prospective cohort (Whitehall II study). Participants (age, 45 to 66 years) were free of clinical cardiovascular disease and diabetes mellitus. Risk factors and Framingham Risk Score were determined at baseline. cIMT was repeated 6.2+/-0.4 years later. At baseline, age, blood pressure, low-density lipoprotein cholesterol, and Framingham Risk Score correlated with cIMT. However, only flow-mediated dilatation, not risk factors or Framingham Risk Score, was associated with average annual progression of cIMT. This relationship remained significant after adjustment for risk factors whether entered as separate variables or as Framingham Risk Score. Further adjustment for waist circumference, triglycerides, and employment grade had no significant effect.
Systemic endothelial function was associated with progression of preclinical carotid arterial disease over a 6-year period and was more closely related to cIMT changes than conventional risk factors. Thus, the relationship between endothelial dysfunction and adverse outcome is likely to be due not only to destabilization of established disease in high-risk populations but also to its impact on the evolution of the atherosclerotic substrate. Flow-mediated dilatation testing provides an integrated vascular measure that may aid the prediction of structural disease evolution and represents a potential short- to intermediate-term outcome measure for evaluation of preventive treatment strategies.
Quasi-static or cyclic loading of an artificial starter crack in unidirectionally fibre-reinforced composite test coupons yields fracture mechanics data-the toughness or strain-energy release rate ...(labelled G)-for characterising delamination initiation and propagation. Thus far, the reproducibility of these tests is typically between 10 and 20%. However, differences in the size and possibly the shape, but also in the fibre lay-up, between test coupons and components or structures raise additional questions: Is G from a coupon test a suitable parameter for describing the behaviour of delaminations in composite structures? Can planar, two-dimensional, delamination propagation in composite plates or shells be properly predicted from essentially one-dimensional propagation in coupons? How does fibre bridging in unidirectionally reinforced test coupons relate to delamination propagation in multidirectional lay-ups of components and structures? How can multiple, localised delaminations-often created by impact in composite structures-and their interaction under service loads with constant or variable amplitudes be accounted for? Does planar delamination propagation depend on laminate thickness, thickness variation or the overall shape of the structure? How does exposure to different, variable service environments affect delamination initiation and propagation? Is the microscopic and mesoscopic morphology of FRP composite structures sufficiently understood for accurate predictive modelling and simulation of delamination behaviour? This contribution will examine selected issues and discuss the consequences for test development and analysis. The discussion indicates that current coupon testing and analysis are unlikely to provide the data for reliable long-term predictions of delamination behaviour in FRP composite structures. The attempts to make the building block design methodology for composite structures more efficient via combinations of experiments and related modelling look promising, but models require input data with low scatter and, even more importantly, insight into the physics of the microscopic damage processes yielding delamination initiation and propagation.
Epidemics in wildlife populations often display a striking seasonality. Ranaviruses can cause rapid, synchronous mass mortality events in populations of wood frog (Rana sylvatica) larvae in the ...summer. While there are several possible explanations for this pattern—from seasonal introductions of the virus to environmental stressors to windows of susceptibility to mortality from infection during development—most studies have focused on single factors in laboratory settings. We characterized the time course of ranavirus epidemics in eight ephemeral ponds in Connecticut, USA, measuring the prevalence and intensity of infections in wood frog larvae and Ranavirus DNA in water samples using environmental DNA methods. We found little evidence that the timing of pathogen introduction affected the timing of epidemics (rising prevalence) or the resulting die-offs. Instead, we observed a pulse in transmission asynchronous with die-offs; prevalence reached high levels (≥ 50%) up to 6 weeks before mortality was observed, suggesting that die-offs may be uncoupled from this pulse in transmission. Rather, mortality occurred when larvae reached later stages of development (hind limb formation) and coinciding water temperatures rose (≥ 15°C), both of which independently increase pathogenicity (i.e., probability of host mortality) of infections in laboratory experiments. In summary, the strong seasonality of die-offs appears to be driven by development-and/or temperature-dependent changes in pathogenicity rather than occurring chronologically with pathogen introduction, after a pulse in transmission, or when susceptible host densities are greatest. Furthermore, our study illustrates the potential for eDNA methods to provide valuable insight in aquatic host–pathogen systems.
The ANTARES neutrino telescope—Status and first results Brunner, J.
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
2011, Letnik:
626
Journal Article
Recenzirano
The construction of ANTARES has been accomplished in May 2008 with the connection of the last two detector lines. The complete detector consists of 885 optical modules which are distributed on 12 ...detector lines, various calibration systems and devices for complementary measurements, the largest of which is an array of 36 acoustics sensors. Valuable data have been accumulated in 2007 with five detector lines and from December 2007 until now with 10 lines and more. In 2009 the line repair concept could be successfully tested with the recovery, repair, redeployment and reconnection of a malfunctioning detector line. Various physics analyses based on the data taken in 2007 and 2008 are ongoing and preliminary results are available.
Aortic stiffness is a strong predictor of cardiovascular disease endpoints. Cross-sectional studies have shown associations of various cardiovascular risk factors with aortic pulse wave velocity, a ...measure of aortic stiffness, but the long-term impact of these factors on aortic stiffness is unknown.
In 3,769 men and women from the Whitehall II cohort, a wide range of traditional and novel cardiovascular risk factors were determined at baseline (1991-1993) and aortic pulse wave velocity was measured at follow-up (2007-2009). The prospective associations between each baseline risk factor and aortic pulse wave velocity at follow-up were assessed through sex stratified linear regression analysis adjusted for relevant confounders. Missing data on baseline determinants were imputed using the Multivariate Imputation by Chained Equations.
Among men, the strongest predictors were waist circumference, waist-hip ratio, heart rate and interleukin 1 receptor antagonist, and among women, adiponectin, triglycerides, pulse pressure and waist-hip ratio. The impact of 10 centimeter increase in waist circumference on aortic pulse wave velocity was twice as large for men compared with women (men: 0.40 m/s (95%-CI: 0.24;0.56); women: 0.17 m/s (95%-CI: -0.01;0.35)), whereas the opposite was true for the impact of a two-fold increase in adiponectin (men: -0.30 m/s (95%-CI: -0.51;-0.10); women: 0.61 m/s (95%-CI: -0.86;-0.35)).
In this large prospective study, central obesity was a strong predictor of aortic stiffness. Additionally, heart rate in men and adiponectin in women predicted aortic pulse wave velocity suggesting that strategies to prevent aortic stiffening should be focused differently by sex.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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