Mechanical loss of a hydroxide catalysis bond between sapphire substrates and its effect on the sensitivity of future gravitational wave detectors

Hydroxide catalysis bonds are low mechanical loss joints which are used in the fused silica mirror suspensions of current room temperature interferometric gravitational wave detectors, one of the techniques which was essential to allow the recent detection of gravitational radiation by LIGO. More sensitive detectors may require cryogenic techniques with sapphire as a candidate mirror and suspension material, and thus hydroxide catalysis bonds are under consideration for jointing sapphire. This paper presents the first measurements of the mechanical loss of such a bond created between sapphire substrates and measured down to cryogenic temperatures. The mechanical loss is found to be 0.03±0.01 at room temperature, decreasing to (3±1)×10−4 at 20 K. The resulting thermal noise of the bonds on several possible mirror suspensions is presented

Prosthesis use is associated with reduced physical self-disgust in limb amputees

Self-disgust is an emotion schema negatively affecting people’s body image and is triggered by bodily imperfections and deviations from the “normal” body envelope. In this study, we explore the idea that “normalising” the body in those with limb amputations via the prosthesis would be linked to reduced self-directed disgust. An international clinical community sample (N = 83) with mostly lower limb amputations completed measures about their demographics, prosthesis, adjustment, body image disturbance, psychological distress, and self-directed disgust in a survey design. Consistent with the “normalising” hypothesis, correlation and bootstrapped regression models revealed, first, that frequency of prosthesis use was significantly and negatively associated with physical self-disgust. Second, prosthesis use significantly mediated the exogenous effect of time since amputation on physical self-disgust. These results emphasise the psychological value of the prosthesis beyond its functional use, and stress its importance in normalising the body envelope in those with limb amputations, which may in turn promote psychological well-being

On the Emergence of Unstable Modes in an Expanding Domain for Energy-Conserving Wave Equations

Motivated by recent work on instabilities in expanding domains in reaction-diffusion settings, we propose an analog of such mechanisms in energy-conserving wave equations. In particular, we consider a nonlinear Schr{\"o}dinger equation in a finite domain and show how the expansion or contraction of the domain, under appropriate conditions, can destabilize its originally stable solutions through the modulational instability mechanism. Using both real and Fourier spacediagnostics, we monitor and control the crossing of the instability threshold and, hence, the activation of the instability. We also consider how the manifestation of this mechanism is modified in a spatially inhomogeneous setting, namely in the presence of an external parabolic potential, which is relevant to trapped Bose-Einstein condensates

Healthcare worker influenza immunization vaccinate or mask policy: Strategies for cost effective implementation and subsequent reductions in staff absenteeism due to illness

AbstractBackgroundA new policy requiring staff in clinical areas to vaccinate or wear a mask was implemented in British Columbia (BC) in the 2012/13 winter. This review assessed the impact of the policy on absenteeism in health care workers.MethodsA retrospective cohort study of full-time HCW that worked prior to and during the 2012/13 influenza season in a health authority in BC. The rate of absenteeism due to all cause illness was compared between vaccinated and unvaccinated staff controlling for behaviors outside influenza season.ResultsOf the 10079 HCW, 77% were vaccinated. By comparison to absenteeism rates in the pre-influenza season, unvaccinated staff in winter had twice the increase in absenteeism due to all-cause illness than vaccinated staff.ConclusionAfter controlling for baseline differences between those vaccinated and unvaccinated, influenza vaccination was associated with reduced absenteeism, saving the Health Authority substantial money. Having regular staff in attendance increases the quality of care

Non-hermitean delocalization in an array of wells with variable-range widths

Nonhermitean hamiltonians of convection-diffusion type occur in the description of vortex motion in the presence of a tilted magnetic field as well as in models of driven population dynamics. We study such hamiltonians in the case of rectangular barriers of variable size. We determine Lyapunov exponent and wavenumber of the eigenfunctions within an adiabatic approach, allowing to reduce the original d=2 phase space to a d=1 attractor. PACS numbers:05.70.Ln,72.15Rn,74.60.GeComment: 20 pages,10 figure

Low expression and promoter hypermethylation of the tumour suppressor SLIT2, are associated with adverse patient outcomes in diffuse large B cell lymphoma

SLIT2 has been classified as a major tumour suppressor gene due to its frequent inactivation in different cancer types. However, alterations of SLIT2 expression and relation to patient outcomes in diffuse large B cell lymphoma (DLBCL) remain undefined. The aim of this study was to investigate the expression and the methylation status of SLIT2 gene as well as its relation to patient outcomes in DLBCL. Immunohistochemical (IHC) staining was carried out to detect the expression of SLIT2 in a series of 108 DLBCL cases. Re-analysis of previously published dataset (GSE10846) that measured gene expression in DLBCL patients who had received CHOP or R-CHOP therapy was performed to identify associations between SLIT2 and patients survival. Laser capture microdissection was performed to isolate GC B cells and DLBCL primary tumor cells. Bisulfite treatment and methylation-specific PCR (MSP) analysis were done to assess SLIT2 promotor methylation status. We report that the expression of SLIT2 protein was reduced in a subset of DLBCL cases and this was significantly correlated with advanced clinical stage (p = 0.041) and was an independent predictor of worse overall survival (OS) (p = 0.012). Re-analysis of published gene expression data showed that reduced SLIT2 mRNA expression was significantly correlated with worse OS in R-CHOP-treated ABC DLBCL patients (p = <0.01). Hypermethylation of the SLIT2 promotor was significantly correlated with low SLIT2 expression (p = 0.009). Our results provide a novel evidence of reduced expression of SLIT2 that is associated with promoter hypermethylation and adverse outcomes in patients with DLBCL

Study of heterogeneous nucleation of eutectic Si in high-purity Al-Si alloys with Sr addition

The official published version can be accessed from the link below - Copyright @ 2010 The Minerals, Metals & Materials Society and ASM InternationalAl-5 wt pct Si master-alloys with controlled Sr and/or P addition/s were produced using super purity Al 99.99 wt pct and Si 99.999 wt pct materials in an arc melter. The master-alloy was melt-spun resulting in the production of thin ribbons. The Al matrix of the ribbons contained entrained Al-Si eutectic droplets that were subsequently investigated. Differential scanning calorimetry, thermodynamic calculations, and transmission electron microscopy techniques were employed to examine the effect of the Sr and P additions on eutectic undercoolings and nucleation phenomenon. Results indicate that, unlike P, Sr does not promote nucleation. Increasing Sr additions depressed the eutectic nucleation temperature. This may be a result of the formation of a Sr phase that could consume or detrimentally affect potent AlP nucleation sites.This work is financially supported by the Higher Education Commission of Pakistan and managerially supported from the OAD

HOPX functions as a tumour suppressor in head and neck cancer.

Head and neck squamous cell carcinoma (HNSCC) is generalized term that encompasses a diverse group of cancers that includes tumours of the oral cavity (OSCC), oropharynx (OPSCC) and nasopharynx (NPC). Genetic alterations that are common to all HNSCC types are likely to be important for squamous carcinogenesis. In this study, we have investigated the role of the homeodomain-only homeobox gene, HOPX, in the pathogenesis of HNSCC. We show that HOPX mRNA levels are reduced in OSCC and NPC cell lines and tissues and there is a general reduction of HOPX protein expression in these tumours and OPSCCs. HOPX promoter methylation was observed in a subset of HNSCCs and was associated with a worse overall survival in HPV negative tumours. RNAseq analysis of OSCC cells transfected with HOPX revealed a widespread deregulation of the transcription of genes related to epithelial homeostasis and ectopic over-expression of HOPX in OSCC and NPC cells inhibited cell proliferation, plating efficiency and migration, and enhanced sensitivity to UVA-induced apoptosis. Our results demonstrate that HOPX functions as a tumour suppressor in HNSCC and suggest a central role for HOPX in suppressing epithelial carcinogenesis

Dynamics of escaping Earth ejecta and their collision probability with different Solar System bodies

It has been suggested that the ejection to interplanetary space of terrestrial crustal material, accelerated in a large impact, may result in the interchange of biological material between Earth and other Solar System bodies. In this paper, we analyze the fate of debris ejected from Earth by means of numerical simulations of the dynamics of a large collection of test particles. This allows us to determine the probability and conditions for the collision of ejecta with other planets of the Solar System. We also estimate the amount of particles falling-back to Earth as a function of time after being ejected. We find that, in general, the collision rates of Earth ejecta with Venus and the Moon, as well as the fall-back rates, are consistent with results reported in the literature. By considering a larger number of particles than in all previous calculations we have also determined directly the collision probability with Mars and, for the first time, computed collision probabilities with Jupiter. We find that the collision probability with Mars is greater than values determined from collision cross section estimations previously reported.Comment: 9 pages, 4 figures & 1 table. Submitted to Icaru

Lymphatic vessel density is associated with CD8⁺ T cell infiltration and immunosuppressive factors in human melanoma.

Increased density of tumor-associated lymphatic vessels correlates with poor patient survival in melanoma and other cancers, yet lymphatic drainage is essential for initiating an immune response. Here we asked whether and how lymphatic vessel density (LVD) correlates with immune cell infiltration in primary tumors and lymph nodes (LNs) from patients with cutaneous melanoma. Using immunohistochemistry and quantitative image analysis, we found significant positive correlations between LVD and CD8 &lt;sup&gt;+&lt;/sup&gt; T cell infiltration as well as expression of the immunosuppressive molecules inducible nitric oxide synthase (iNOS) and 2,3-dioxygénase (IDO). Interestingly, similar associations were seen in tumor-free LNs adjacent to metastatic ones, indicating loco-regional effects of tumors. Our data suggest that lymphatic vessels play multiple roles at tumor sites and LNs, promoting both T cell infiltration and adaptive immunosuppressive mechanisms. Lymph vessel associated T cell infiltration may increase immunotherapy success rates provided that the treatment overcomes adaptive immune resistance