4,013 research outputs found
Study of Gaseous Emissions Derived from the Combustion of Diesel/Beef Tallow Biodiesel Blends
Air pollution is one of the main environmental problems of modern society. The road and transportation segment is a key source of polluting gases worldwide. In its research for transportation’s emission reduction alternatives, the Brazilian government instituted a wide-spread biodiesel, adding 7% (B7) of biodiesel to the diesel used in the country. Therefore, studies such as this must be carried out to guarantee the environmental sustainability of the new matrix of renewable energies, with the useof biofuels, as well as evaluate the gases emitted to for the environment by the combustion of the same ones. This work was detected CO, CO2 and NO gas emissions released into the atmosphere from the combustion of blends diesel/beef tallow biodiesel in a bench-scale engine. Using electrochemical sensors, the of these gases concentration were successfully registered for two modes of operation of the engine diesel, low rotation, 3500 rpm, and high rotation, 7000 rpm. The CO levels in this experiment in low rotation varied between values minimum and maximum range of 866.7 to 1333.3 ppm, and in high rotation, ranging of 666 and 1000 ppm respectively. For the CO2 concentration in low rotation varied between values minimum and maximum range of 2.1 to 2.4%, and high rotation, ranging of 2.2 to 2.5%, and for NO concentrations of the samples for the mode low rotation had a variation of 83 to 109.5 ppm, and for high rotation were 81.7 to 98.7 ppm respectively
Geometrical effect characterization of femtosecond-laser manufactured glass microfluidic chips based on optical manipulation of submicroparticles
Quantitative magnetization transfer imaging as a biomarker for effects of systemic inflammation on the brain
BACKGROUND
Systemic inflammation impairs brain function and is increasingly implicated in the etiology of common mental illnesses, particularly depression and Alzheimer's disease. Immunotherapies selectively targeting proinflammatory cytokines demonstrate efficacy in a subset of patients with depression. However, efforts to identify patients most vulnerable to the central effects of inflammation are hindered by insensitivity of conventional structural magnetic resonance imaging.
METHODS
We used quantitative magnetization transfer (qMT) imaging, a magnetic resonance imaging technique that enables quantification of changes in brain macromolecular density, together with experimentally induced inflammation to investigate effects of systemic inflammatory challenge on human brain microstructure. Imaging with qMT was performed in 20 healthy participants after typhoid vaccination and saline control injection. An additional 20 participants underwent fluorodeoxyglucose positron emission tomography following the same inflammatory challenge.
RESULTS
The qMT data demonstrated that inflammation induced a rapid change in brain microstructure, reflected in increased magnetization exchange from free (water) to macromolecular-bound protons, within a discrete region of insular cortex implicated in representing internal physiologic states including inflammation. The functional significance of this change in insular microstructure was demonstrated by correlation with inflammation-induced fatigue and fluorodeoxyglucose positron emission tomography imaging, which revealed increased resting glucose metabolism within this region following the same inflammatory challenge.
CONCLUSIONS
Together these observations highlight a novel structural biomarker of the central physiologic and behavioral effects of mild systemic inflammation. The widespread clinical availability of magnetic resonance imaging supports the viability of qMT imaging as a clinical biomarker in trials of immunotherapeutics, both to identify patients vulnerable to the effects of systemic inflammation and to monitor neurobiological responses
Transcriptional regulation of endothelin-1 expression by advanced glycation end-products in human aortic endothelium is mediated via NF-kappaΒ and AP-1
Advanced Glycation End-products (AGEs) are produced by the non-enzymatic glycation of proteins, lipids and nucleic acids, resulting in an overload of highly reactive molecules of endogenous or exogenous (dietary) origin.
Increased AGE levels in circulation and concomitant elevated tissue deposition have been associated with diabetic complications, atheromatosis, ageing and more recently with polycystic ovary syndrome pathogenesis.
Interaction of AGEs with their receptor RAGE (Receptor for AGEs) activates intracellular signaling pathways which induce targeted gene expression in endothelium including upregulation of cell adhesion molecules and endothelin-1 (ET-1), implicated in vascular injury and endothelial dysfunction.
The purpose of this study is to explore the molecular mechanism of AGE-induced regulation of ET-1 gene/protein expression in human endothelial cells and investigate its functional relevance in normal rat vascular endothelium
Observation of Squeezed Light in the 2 Μm Region
We present the generation and detection of squeezed light in the 2 μm wavelength region. This experiment is a crucial step in realizing the quantum noise reduction techniques that will be required for future generations of gravitational-wave detectors. Squeezed vacuum is generated via degenerate optical parametric oscillation from a periodically poled potassium titanyl phosphate crystal, in a dual resonant cavity. The experiment uses a frequency stabilized 1984 nm thulium fiber laser, and squeezing is detected using balanced homodyne detection with extended InGaAs photodiodes. We have measured 4.0±0.1 dB of squeezing and 10.5±0.5 dB of antisqueezing relative to the shot noise level in the audio frequency band, limited by photodiode quantum efficiency. The inferred squeezing level directly after the optical parametric oscillator, after accounting for known losses and phase noise, is 10.7 dB
Under-reporting bicycle accidents to police in the COST TU1101 international survey: Cross-country comparisons and associated factors
Police crash reports are often the main source for official data in many countries. However, with the exception of fatal crashes, crashes are often underreported in a biased manner. Consequently, the countermeasures adopted according to them may be inefficient. In the case of bicycle crashes, this bias is most acute and it probably varies across countries, with some of them being more prone to reporting accidents to police than others. Assessing if this bias occurs and the size of it can be of great importance for evaluating the risks associated with bicycling. This study utilized data collected in the COST TU1101 action “Towards safer bicycling through optimization of bicycle helmets and usage”. The data came from an online survey that included questions related to bicyclists' attitudes, behaviour, cycling habits, accidents, and patterns of use of helmets. The survey was filled by 8655 bicyclists from 30 different countries. After applying various exclusion factors, 7015 questionnaires filled by adult cyclists from 17 countries, each with at least 100 valid responses, remained in our sample. The results showed that across all countries, an average of only 10% of all crashes were reported to the police, with a wide range among countries: from a minimum of 0.0% (Israel) and 2.6% (Croatia) to a maximum of a 35.0% (Germany). Some factors associated with the reporting levels were type of crash, type of vehicle involved, and injury severity. No relation was found between the likelihood of reporting and the cyclist's gender, age, educational level, marital status, being a parent, use of helmet, and type of bicycle. The significant under-reporting – including injury crashes that do not lead to hospitalization – justifies the use of self-report survey data for assessment of bicycling crash patterns as they relate to (1) crash risk issues such as location, infrastructure, cyclists' characteristics, and use of helmet and (2) strategic approaches to bicycle crash prevention and injury reduction.Fil: Shinar, D.. Ben Gurion University of the Negev; IsraelFil: Valero Mora, Pedro. Universidad de Valencia; EspañaFil: van Strijp Houtenbos, M.. Institute For Road Safety Research; Países BajosFil: Haworth, N.. Queensland University of Technology; AustraliaFil: Schramm, A.. Queensland University of Technology; AustraliaFil: de Bruyne, G.. Universiteit Antwerp; BélgicaFil: Cavallo, V.. No especifíca;Fil: Chliaoutakis, J.. No especifíca;Fil: Pereira Dias, Joao. Instituto Superior Tecnico; PortugalFil: Ferraro, Ottavia Eleonora. Universita Degli Studi Di Pavia; ItaliaFil: Fyhri, Aslak. No especifíca;Fil: Sajatovic, Anika Hursa. No especifíca;Fil: Kuklane, Kalev. Lund University; SueciaFil: Ledesma, Ruben Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Psicología Básica, Aplicada y Tecnología. Universidad Nacional de Mar del Plata. Facultad de Psicología. Instituto de Psicología Básica, Aplicada y Tecnología.; ArgentinaFil: Calvé Mascarell, Oscar. Ben Gurion University of the Negev; IsraelFil: Morandi, A.. Universita Degli Studi Di Pavia; ItaliaFil: Muser, Markus. No especifíca;Fil: Otte, Diettmar. No especifíca;Fil: Papadakaki, M.. No especifíca;Fil: Sanmartín, J.. Universidad de Valencia; EspañaFil: Dulf, D.. No especifíca;Fil: Saplioglu, M.. No especifíca;Fil: Tzamalouka, Georgia. No especifíca
Spinal versus General Anaesthesia in Postoperative Pain Management during Transurethral Procedures
We compared the analgesic efficacy of spinal and general anaesthesia following transurethral procedures. 97 and 47 patients underwent transurethral bladder tumour resection (TUR-B) and transurethral prostatectomy (TUR-P), respectively. Postoperative pain was recorded using an 11-point visual analogue scale (VAS). VAS score was greatest at discharge from recovery room for general anaesthesia (P = 0.027). The pattern changed significantly at 8 h and 12 h for general anaesthesia's efficacy (P = 0.017
and P = 0.007,
resp.). A higher VAS score was observed in pT2 patients. Patients with resected tumour volume >10 cm3 exhibited a VAS score >3 at 8 h and 24 h (P = 0.050, P = 0.036, resp.). Multifocality of bladder tumours induced more pain overall. It seems that spinal anaesthesia is more effective during the first 2 postoperative hours, while general prevails at later stages and at larger traumatic surfaces. Finally, we incidentally found that tumour stage plays a significant role in postoperative pain, a point that requires further verification
Consequences of information suppression in ecological and conservation sciences
Suppressing expert knowledge can hide environmentally damaging practices and policies from public scrutiny. We surveyed ecologists and conservation scientists from universities, government, and industry across Australia to understand the prevalence and consequences of suppressing science communication. Government (34%) and industry (30%) respondents reported higher rates of undue interference by employers than did university respondents (5%). Internal communications (29%) and media (28%) were curtailed most, followed by journal articles (11%), and presentations (12%). When university and industry researchers avoided public commentary, this was mainly for fear of media misrepresentation, while government employees were most often constrained by senior management and workplace policy. One third of respondents reported personal suffering related to suppression, including job losses and deteriorating mental health. Substantial reforms are needed, including to codes of practice, and governance of environmental assessments and research, so that scientific advice can be reported openly, in a timely manner and free from interference
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