The Charge Collection Properties of CVD Diamond

The charge collection properties of CVD diamond have been investigated with ionising radiation. In this study two CVD diamond samples, prepared with electrical contacts have been used as solid state ionisation chambers. The diamonds have been studied with beta particles and 10 keV photons, providing a homogeneous ionisation density and with protons and alpha particles which are absorbed in a thin surface layer. For the latter case a strong decrease of the signal as function of time is observed, which is attributed to polarisation effects inside the diamond. Spatially resolved measurements with protons show a large variation of the charge collection efficiency, whereas for photons and minimum ionising particles the response is much more uniform and in the order of 18%. These results indicate that the applicability of CVD diamond as a position sensitive particle detector depends on the ionisation type and appears to be promising for homogeneous ionisation densities as provided by relativistic charged particles.Comment: 26 pages (Latex), submitted to NIM

Associating Emergency Medical Services personnel's workload, trauma exposure, and health with the cortisol, endocannabinoid, and N-acylethanolamine concentrations in their hair

In their line of duty, Emergency Medical Services (EMS) personnel are exposed to chronically stressful working conditions and recurrent traumatic events, which increase their risk for detrimental health outcomes. Here, we investigated whether this risk is due to altered regulation of the hypothalamus-pituitary-adrenal (HPA) axis and the endocannabinoid system. Therefore, 1 cm hair strands were collected from a cohort of 72 German EMS personnel in order to measure concentrations of cortisol, endocannabinoids [i.e., anandamide (AEA), 2-arachidonoylglycerol (2-AG)], and N-acylethanolamines [i.e., stearoylethanolamide (SEA), oleoylethanolamide (OEA), and palmitoylethanolamide (PEA)]. Rank correlation analyses were conducted to test associations of cortisol, endocannabinoid, and N-acylethanolamine concentrations with the EMS personnel's workload, lifetime trauma exposure, and mental and physical health problems. We found a negative correlation between cortisol and 2-AG concentrations in hair. Higher hair cortisol was associated with higher workload. Reported traumatic stress during childhood and later in life as well as more severe depressive and physical stress symptoms were associated with elevated 2-AG, SEA, OEA, and PEA concentrations. Future longitudinal research needs to address the prospect of tracing biomolecular markers of glucocorticoid, endocannabinoid, and N-acylethanolamine activity as a predicting value of the long-term course of mental and physical well-being

Emotion Regulation in Rescue Workers: Differential Relationship With Perceived Work-Related Stress and Stress-Related Symptoms

Rescue workers are exposed to enduring emotional distress, as they are confronted with (potentially) traumatic mission events and chronic work-related stress. Thus, regulating negative emotions seems to be crucial to withstand the work-related strain. This cross-sectional study investigated the influence of six emotion regulation strategies (i.e., rumination, suppression, avoidance, reappraisal, acceptance, and problem solving) on perceived work-related stress and stress-related depressive, post-traumatic, and somatic symptoms in a representative sample of 102 German rescue workers. Multiple regression analyses identified rumination and suppression to be associated with more work-related stress and stress-related symptoms. Acceptance was linked to fewer symptoms and, rather unexpectedly, avoidance was linked to less work-related stress. No effects were observed for reappraisal and problem solving. Our findings confirm the dysfunctional role of rumination and suppression for the mental and physical health of high-risk populations and advance the debate on the context-specific efficacy of emotion regulation strategies

Efficient Elimination of Inhaled Nanoparticles from the Alveolar Region: Evidence for Interstitial Uptake and Subsequent Reentrainment onto Airways Epithelium

BACKGROUND: There is ongoing discussion that inhaled nanoparticles (NPs, < 100 nm) may translocate from epithelial deposition sites of the lungs to systemic circulation. OBJECTIVES AND METHODS: We studied the disappearance of NPs from the epithelium by sequential lung retention and clearance and bronchoalveolar lavage (BAL) measurements in healthy adult Wistar Kyoto (WKY) rats at various times over 6 months after administration of a single 60- to 100-min intratracheal inhalation of iridium-192 ((192)Ir)–radiolabeled NPs. A complete (192)Ir balance of all organs, tissues, excretion, remaining carcass, and BAL was performed at each time point. RESULTS: Directly after inhalation we found free NPs in the BAL; later, NPs were predominantly associated with alveolar macropages (AMs). After 3 weeks, lavageable NP fractions decreased to 0.06 of the actual NP lung burden. This is in stark contrast to the AM-associated fraction of micron-sized particles reported in the literature. These particles remained constant at about 0.8 throughout a 6-month period. Three weeks after inhalation, 80% of the retained Ir NPs was translocated into epithelium and interstitium. CONCLUSION: There is a strong size-selective difference in particle immobilization. Furthermore, AM-mediated NP transport to the larynx originates not only from the NP fraction retained on the epithelium but also from NPs being reentrained from the interstitium to the luminal side of epithelium. We conclude that NPs are much less phagocytized by AMs than large particles but are effectively removed from the lung surface into the interstitium. Even from these interstitial sites, they undergo AM-mediated long-term NP clearance to the larynx

Contribution of breast volume and weight to body fat distribution in females

Breast volume and body composition were measured in 45 adult females to determine the contribution of breast weight and breast volume to total body fat. Plaster casts were filled with sand of known density to obtain breast volume. Breast weight was computed as breast volume times its density. The correlation between total breast volume and percent body fat was r = .40. Breast weight ( X = 484 grams) accounted for 3.5 percent of the total weight of body fat, and at most, 12 percent of the estimated quantities of sex-specific fat. A theoretical model is proposed for the distribution of body fat in the female which subdivides total body fat into three components: reserve storage fat, essential fat, and expendable storage fat.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/37602/1/1330530113_ftp.pd