Measurement of Cosmic-ray Muon-induced Spallation Neutrons in the Aberdeen Tunnel Underground Laboratory

AbstractMuon-induced neutrons are one of the major backgrounds to various underground experiments, such as dark matter searches, low-energy neutrino oscillation experiments and neutrino-less double beta-decay experiments. Previous experiments on the underground production rate of muon-induced neutrons were mostly carried out either at shallow sites or at very deep sites. The Aberdeen Tunnel experiment aims to measure the neutron production rate at a moderate depth of 611 meters water equivalent. Our apparatus comprises of six layers of plastic-scintillator hodoscopes for tracking the incident cosmic-ray muons, and 760 L of gadolinium-doped liquid-scintillator for both neutron production and detection targets. In this paper, we describe the design and the performance of the apparatus. The preliminary result on the measurement of neutron production rate is also presented

Analysis of positive Edinburgh depression scale referrals to a consultation liaison psychiatry service in a two-year period

Antenatal depression is a depressive episode that beings in pregnancy and is often a predictor of postnatal depression. The main aim of this study was to examine the prevalence of antenatal depression and other psychiatric conditions in women referred to a consultation liaison psychiatry service because of positive scores on the Edinburgh Postnatal Depression Scale. The other aim was to review known risk factors in the women and note any significant findings. An audit of all women referred to the psychiatry team because of positive Edinburgh scores during a 2-year period was completed. Information about Edinburgh scores, clinical diagnoses at the time of the psychiatric appointment, and factors such as relationship status, domestic violence, ethnicity, and substance use was noted. According to the Diagnostic and Statistical Manual of Mental Disorders: Fourth Edition criteria: 36.5% of the women had an adjustment disorder, 13% had a major depression, 10% had dysthymia, 8% had a recurrent depressive disorder, 2% had post-traumatic stress disorder, and 2% had a borderline personality disorder. The findings demonstrated the usefulness of using a screening tool such as the Edinburgh Postnatal Depression Scale in detecting women requiring psychiatric intervention and highlighted the importance of a psychiatric interview assessment to interpret the scores of screened patients in terms of clinically relevant syndromes

Proton beam writing of low-loss polymer optical waveguides

10.1063/1.1606502Applied Physics Letters8391707-1709APPL

Effects of aluminum on the parathyroid-hormone receptors of bone and kidney

Effects of aluminum on the parathyroid hormone receptors of bone and kidney. Aluminum intoxication is associated with low osseous remodeling rate and peripheral resistance to parathyroid hormone (PTH). The pathophysiological mechanism of these aluminum induced changes was investigated using cultured clonal osteoblastic UMR-106 cells as well as dog renal cortical membrane. Both systems possess high-affinity PTH receptors that are coupled to adenylate cyclase. The UMR-106 cells have typical osteoblastic features, including receptors for the tissue-specific hormones, formation and mineralization of a bone-like ground substance and exclusive synthesis of type 1 collagen. The results show that aluminum at a concentration of 4 microM and 40 microM significantly inhibits the cyclic AMP responses to PTH challenge in UMR-106 cells, and this is associated with significant decrease in the binding to the PTH receptor. At 200 microM no PTH-responsive adenylate cyclase or binding to receptor can be demonstrated. The effect of aluminum on UMR-106 rat osteosarcoma cells is not due to changes in cell number, cell viability or rate of mitogenesis. Similar results are obtained with dog kidney membrane. At a concentration of 10 microM and 400 microM there is significant inhibition of the binding of PTH to kidney membrane and proportional decrease in PTH-stimulated adenylate cyclase. With higher concentration of aluminum, no response or binding can be demonstrated. In conclusion, aluminum at concentrations of 4 to 400 microM is associated with a decrease in affinity of PTH receptor and concomitant suppression of PTH-stimulated adenylate cyclase. The two processes are affected to a similar degree by different concentrations of aluminum, and it is likely that the primary effect of aluminum is on the affinity of the receptor which may be related to exchange of aluminum with magnesium at G-protein. This effect could account for the observed peripheral resistance to PTH in aluminum intoxication as well as the suppression of osseous remodeling rate in these patients