Highly sensitive p-type 4H-SiC van der Pauw sensor

This paper presents for the first time a p-type 4H silicon carbide (4H-SiC) van der Pauw strain sensor by utilizing the strain induced effect in four-terminal devices. The sensor was fabricated from a 4H-SiC (0001) wafer, using a 1 μm thick p-type epilayer with a concentration of 10¹⁸ cm⁻³. Taking advantage of the four-terminal configuration, the sensor can eliminate the need for resistance-to-voltage conversion which is typically required for two-terminal devices. The van der Pauw sensor also exhibits an excellent repeatability and linearity with a significantly large output voltage in induced strain ranging from 0 to 334 ppm. Various sensors aligned in different orientations were measured and a high sensitivity of 26.3 ppm⁻¹ was obtained. Combining these performances with the excellent mechanical strength, electrical conductivity, thermal stability, and chemical inertness of 4H-SiC, the proposed sensor is promising for strain monitoring in harsh environments.

This paper presents for the first time a p-type 4H silicon carbide (4H-SiC) van der Pauw strain sensor by utilizing the strain induced effect in four-terminal devices.     

Advanced musculoskeletal physiotherapists in post arthroplasty review clinics: a state wide implementation program evaluation

Objective

To evaluate outcomes following a state-wide implementation of post arthroplasty review (PAR) clinics for patients following total hip and knee arthroplasty, led by advanced musculoskeletal physiotherapists in collaboration with orthopaedic specialists.

Establishing smoke-free hospitals in Vietnam: A pilot project

In Vietnam, a pilot ‘smoke-free hospital’ model was implemented in nine hospitals in 2009–2010 to supply lessons learned that would facilitate a replication of this model elsewhere. This study aimed to assess smoking patterns among health professionals and to detect levels of second-hand smoke (SHS) exposure within hospital premises before and after the ‘smoke-free hospital’ model implementation. A pre- and post-intervention cross-sectional study was conducted in nine purposively selected hospitals. Air nicotine levels were measured using passive nicotine monitors; smoking evidence was collected through on-site observations; and smoking patterns were assessed through interviews with health workers. Despite the ‘smoke-free hospital’ intervention, smoking continued among health-care workers who were former smokers. Specifically, self-reported smoking prevalence significantly decreased post-intervention, but the number of daily cigarettes smoked at workplaces among male health workers remained unchanged. Post-intervention, smoking was more likely to take place outside buildings and cafeterias. However, air nicotine levels in the doctors' lounges and in emergency departments did not change post-intervention. Air nicotine levels at other sites decreased minimally. Tailored tobacco cessation programmes, targeting current smokers and mechanisms to enforce non-smoking, should be established to meet requirements of Vietnam's comprehensive National Tobacco Control Law effective in May 2013.     

An efficient access to β-ketosulfones via β-sulfonylvinylamines: metal–organic framework catalysis for the direct C–S coupling of sodium sulfinates with oxime acetates

A copper-based framework Cu₂(OBA)₂(BPY) was synthesized and used as a recyclable heterogeneous catalyst for the synthesis of β-sulfonylvinylamines from sodium sulfinates and oxime acetates via direct C–S coupling reaction. The transformation was remarkably affected by the solvent, and chlorobenzene emerged as the best option. This Cu-MOF displayed higher activity than numerous conventional homogeneous and MOF-based catalysts. The catalyst was reutilized many times in the synthesis of β-sulfonylvinylamines without considerably deteriorating in catalytic efficiency. These β-sulfonylvinylamines were readily converted to the corresponding β-ketosulfones via a hydrolysis step with aqueous HCl solution. To the best of our knowledge, this direct C–S coupling reaction to achieve β-sulfonylvinylamines was not previously conducted with a heterogeneous catalyst.

Cu₂(OBA)₂(BPY) was used as catalyst for the synthesis of β-sulfonylvinylamines from sodium sulfinates and oxime acetates. These β-sulfonylvinylamines were readily converted to corresponding β-ketosulfones via a hydrolysis step.     

Fasting insulin and uric acid levels but not indices of iron metabolism are independent predictors of non-alcoholic fatty liver disease. A case-control study

BACKGROUND: Non-alcoholic fatty liver disease is a common reason for hepatological consultation and may herald severe hepatic and extra-hepatic disease. The aetiopathogenesis of this condition is an area of increasing interest. AIM: To evaluate anthropometric and biochemical factors associated to non-alcoholic fatty liver disease in a case-control study. Methods. Demographic and biochemical data of 60 consecutive patients with bright liver absent-to-low alcohol consumption, no evidence of viral, genetic and autoimmune diseases, were compared to those of 60 age- and gender-matched historical controls without fatty liver by univariate and multiple logistic regression analysis. RESULTS: Patients were more often hypertriglyceridaemic, obese and diabetic than controls (p<.01). Mean values of alanine transaminase, gammaglutamyltranspeptidase, triglycerides, uric acid, fasting and log insulin, transferrin percent saturation and ferritin were significantly higher in the patients, while transferrin and quantitative insulin sensitivity check index, a quantitative insulin sensitivity index, were lower. No iron storage was found in those who underwent liver biopsy At univariate analysis the relative risk for non-alcoholic fatty liver disease significantly increased (p<0. 05) with increasing body mass index, fasting insulin, alanine transaminase, uric acid, triglycerides and gammaglutamyltranspeptidase; it decreased with increasing transferrin and quantitative insulin sensitivity check index. Multiple logistic regression analysis disclosed only fasting insulin and uric acid to be independent predictors of non-alcoholic fatty liver disease (p<0.05). CONCLUSIONS: Fasting insulin and serum uric acid levels indicating insulin resistance, but not indices of iron overload, are independent predictors of non-alcoholic fatty liver disease.     

Cholangiocarcinomas express Fas ligand and disable the Fas receptor

Cholangiocarcinoma is a highly-malignant adenocarcinoma originating from cholangiocytes. Current concepts support escape from immune surveillance using aberrant expression of Fas ligand (FasL) and dysregulation of receptor (FasR) signaling as a potential mechanism for tumor progression. Our aims were to determine if altered expression of FasR and FasL or changes in expression of FLICE inhibitor (I-FLICE) allow cholangiocarcinoma cells to escape immune surveillance. Human cholangiocarcinoma cell lines were evaluated for the functional expression of FasR and FasL by (1) quantitating apoptosis after incubation of cells with agonistic antibodies and (2) an in vitro cell death assay involving coculture of cholangiocarcinoma cells with Fas-sensitive thymocytes. I-FLICE antisense treatment was performed by stable transfection with complementary DNA (cDNA) for I-FLICE in the reverse orientation. We found that normal cholangiocytes in vivo express FasL. Human cholangiocarcinoma cell lines express both FasL and FasR and I-FLICE. FasL expressed by cholangiocarcinomas in vitro induced lymphocyte cell death (70% after 24 hours). Despite the expression of FasR, exposure of the cells to agonistic antibodies (500 ng/mL) induced only minimal apoptosis in the Jurkat cells. Antisense treatment of cholangiocarcinomas in vitro with I-FLICE reduced protein expression of I-FLICE by 90% to 95% and increased Fas-mediated apoptosis 2-fold. We concluded that cholangiocarcinomas escape immune surveillance either by disabling FasR signaling through the expression of I-FLICE and/or increased FasL expression to induce apoptosis of invading T cells. Reduction of I-FLICE expression in cholangiocarcinoma cells restored Fas-mediated apoptosis. Therapeutic maneuvers to inhibit expression of I-FLICE may aid in the treatment of cholangiocarcinoma.     

Electrocortical processing of social signals of threat in combat-related post-traumatic stress disorder

Post-traumatic stress disorder (PTSD) is characterized by avoidance, emotional numbing, increased arousal and hypervigilance for threat following a trauma. Thirty-three veterans (19 with PTSD, 14 without PTSD) who had experienced combat trauma while on deployment in Iraq and/or Afghanistan completed an emotional faces matching task while electroencephalography was recorded. Vertex positive potentials (VPPs) elicited by happy, angry and fearful faces were smaller in veterans with versus without PTSD. In addition, veterans with PTSD exhibited smaller late positive potentials (LPPs) to angry faces and greater intrusive symptoms predicted smaller LPPs to fearful faces in the PTSD group. Veterans with PTSD were also less accurate at identifying angry faces, and accuracy decreased in the PTSD group as hyperarousal symptoms increased. These findings show reduced early processing of emotional faces, irrespective of valence, and blunted prolonged processing of social signals of threat in conjunction with impaired perception for angry faces in PTSD.     

Enhanced solar photothermal effect of PANi fabrics with plasmonic nanostructures

The photothermal energy conversion in hanging and floating polyaniline (PANi)-cotton fabrics is investigated using a model based on the heat diffusion equation. Perfect absorption and anti-reflection of wet hanging PANi-cotton fabrics cause quick transfer of total incident light into water confining nearly 100% of the sunlight. As a result, a hanging membrane is found to have more attractive properties than a floating above water fabric. We find, however, that the photothermal properties of a floating PANi-cotton membrane can greatly be enhanced by dispersing TiN nanoparticles in the water below the fabric. The calculated temperature gradients for TiN nanoparticle solutions show that the absorbed energy grows with increasing the nanoparticle density and that the photothermal process occurs mostly near the surface. The collective heating effects depend on the size and density of nanoparticles, which can further be used to modulate the photothermal process.

The photothermal energy conversion in hanging and floating polyaniline (PANi)-cotton fabrics is investigated using a model based on the heat diffusion equation.