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Metal oxide type (MOx) sensors are one of several technologies being employed in low-cost air quality monitors. Their size and cost make them ideally suited for portable and remote monitoring applications. Quantifying the sensor response, however, remains a significant challenge due to sensitivity to ambient temperature and humidity, and interference with non-target pollutant species. Temporal characteristics such as signal hysteresis and sensor drift over time also affect MOx sensor response. We present a quantification model rooted in principles of semiconductor science and chemistry, yet informed by and simplified using empirical observations. This model predicts concentration from resistance while providing a correction for temperature effects, usually the most significant confounder in ambient air quality monitoring with MOx sensors, and drift due to change in the sensor heating element. The model parameter values are first determined using lab calibrations, then refined using a field collocation with reference instruments. The work thus provides both a quantification model and a means to effectively calibrate sensors for practical applications. [ABSTRACT FROM AUTHOR]

We evaluated, by proteomic analysis, whether the chemical changes provoked on enamel by acidulated phosphate fluoride (APF) application alter the protein composition of acquired enamel pellicle. Enamel slabs, pretreated with distilled water (negative control), phosphoric acid (active control) or APF solution, were immersed in human saliva for pellicle formation. The adsorbed proteins were extracted and analyzed by liquid chromatography-mass spectrometry/mass spectrometry. Fifty-six proteins were identified, 12 exclusive to APF and 11 to phosphoric acid. APF decreased the concentration of histatin-1, but increased the concentration of S100-A9, which is confirmed by immunoblotting. The findings suggest that APF application changes the acquired enamel pellicle composition. Copyright © 2013 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Acute gastrointestinal (GI) haemorrhage is a common condition that can be life threatening. The majority of patients will settle with conservative management. Patients who have persistent bleeding and haemodynamic compromise will require urgent investigation. Upper GI haemorrhage is usually investigated by endoscopy and therapeutic endoscopic techniques will control the bleeding in many patients. Patients with upper GI bleeding who fail endoscopic therapy should undergo CT scanning for initial localisation and confirmation of the active bleeding. Treatment by embolisation may be possible although there is a rich collateral supply. Lower GI bleeding is more frequently investigated and treated by radiological means. CT angiography is invaluable as an initial test to identify and localise active bleeding. Patients with a negative CT scan can be managed conservatively. Lower GI embolisation is a safe technique although there is a significant risk of rebleeding, which can be retreated with embolisation. [ABSTRACT FROM AUTHOR]

Presents information on a study which characterized the gamma and X-ray scintillation properties of a lutetium pyro-silicate material. Material preparation; Optical properties; Pulse height measurements; Decay time measurements; Conclusions.

This article presents a comparison of proteases extracted from Caligus elongatus and Lepeophtheirus sabnonis. Both Caligus elongatus and Lepeophtheirus sabnonis are parasitic caligid copepods that inflict considerable damage on farmed salmonids in sea water. Both species, as preadults and adults, are mobile over the skin of their hosts and graze upon the mucus and epithelial cells. However, if the intensity of infestation is high, the epithelial browsing can result in deeper damage to the skin leading to extensive ulceration. Control samples were incubated with the same volume of isopropanol. Low molecular weight standard proteins were obtained from Pharmacia.

The article presents a case study of an 84-year old woman who suffered constipation. It mentions that a computed tomography (CT) scan depicted a sigmoid tumor with metastases, wherein biopsies and sigmoidoscopy showed a rectosigmoid adenocarcinoma. Moreover, 4 months later the patient's died at home, wherein her post-operative course was without complication.

We developed and validated an automated, inexpensive, and continuous multiple-species gas-flux monitoring system that can provide data for a variety of relevant atmospheric pollutants, including O3, CO2, and NOx. Validation consisted of conducting concurrent gas-phase dry-deposition experiments, using both dynamic flux chambers and an eddy-covariance system, in a grassy clearing in the Duke Forest (Chapel Hill, NC). Experiments were carried out in June and September under a variety of meteorological conditions. Ozone-deposition measurements from the two methods matched very well (4-10 % difference in mean flux rate) when the leaf-area index (LAI) inside the chambers was representative of the average LAI in the field. The dynamic flux chambers can be considered an accurate measurement system under these conditions. [ABSTRACT FROM AUTHOR]

Advances in embedded systems and low-cost gas sensors are enabling a new wave of low cost air quality monitoring tools. Our team has been engaged in the development of low-cost wearable air quality monitors (M-Pods) using the Arduino platform. The M- Pods use commercially available metal oxide semiconductor (MOx) sensors to measure CO, O3, NO2, and total VOCs, and NDIR sensors to measure CO2. MOx sensors are low in cost and show high sensitivity near ambient levels; however they display nonlinear output signals and have cross sensitivity effects. Thus, a quantification system was developed to convert the MOx sensor signals into concentrations. Two deployments were conducted at a regulatory monitoring station in Denver, Colorado. M-Pod concentrations were determined using laboratory calibration techniques and co-location calibrations, in which we place the M-Pods near regulatory monitors to then derive calibration function coefficients using the regulatory monitors as the standard. The form of the calibration function was derived based on laboratory experiments. We discuss various techniques used to estimate measurement uncertainties. A separate user study was also conducted to assess personal exposure and M-Pod reliability. In this study, 10 M-Pods were calibrated via co-location multiple times over 4 weeks and sensor drift was analyzed with the result being a calibration function that included drift. We found that co-location calibrations perform better than laboratory calibrations. Lab calibrations suffer from bias and difficulty in covering the necessary parameter space. During co-location calibrations, median standard errors ranged between 4.0-6.1 ppb for O3, 6.4-8.4 ppb for NO2, 0.28-0.44 ppm for CO, and 16.8 ppm for CO2. Median signal to noise (S/N) ratios for the M-Pod sensors were higher for M-Pods than the regulatory instruments: for NO2, 3.6 compared to 23.4; for O3, 1.4 compared to 1.6; for CO, 1.1 compared to 10.0; and for CO2, 42.2 compared to 300-500. The user study provided trends and location-specific information on pollutants, and affected change in user behavior. The study demonstrated the utility of the M-Pod as a tool to assess personal exposure. [ABSTRACT FROM AUTHOR]

Abstract: We report a six and three years follow-up clinical evaluation of two bilateral hand allotransplantations from brain-dead multi-organs donors performed in two young adult traumatic hand amputees. Lifelong immunosuppressive treatment included tacrolimus, mycophenolate mofetil and prednisolone. In both patients, early complications were observed but were successfully treated. At follow-up, clinical results allow useful hand function in both patients, by far superior to what can be provided by current myoelectric prostheses. Although the long-term risks–benefits ratio of bilateral hand transplantation is still unknown, these two cases demonstrate that this new treatment is feasible. Further experimental and clinical research is needed to better delineate its role in the future of hand surgery. [Copyright &y& Elsevier]

B Background: b There are a number of treatment options to palliate patients with unresectable hepatocarcinoma (HCC), but they must be tailored carefully. Aim of this study was to evaluate the safety and efficacy of conventional transarterial chemoembolization (cTACE) in elderly patients treated at the Royal Infirmary of Edinburgh. B Conclusion: b Elderly patients treated with TACE for unresectable HCC have good OS with low complication rate. [Extracted from the article]

B Background: b There are a number of treatment options to palliate patients with unresectable hepatocarcinoma (HCC), but they must be tailored carefully. Aim of this study was to evaluate the safety and efficacy of conventional transarterial chemoembolization (cTACE) in elderly patients treated at the Royal Infirmary of Edinburgh. B Conclusion: b Elderly patients treated with TACE for unresectable HCC have good OS with low complication rate. [Extracted from the article]