620 research outputs found

    Bending force of LLDPE monofilaments at high temperatures measured in DMA (Dynamic Mechanical Analyzer)

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    The bending force of monofilaments used as pile layer in artificial turf football fields is a very important property due to the strong relation with the performance of the entire system being the force that mostly influences the deformation of monofilaments. The existing test methods for measuring this force can only be used to perform tests at room temperature. Nowadays, artificial turf surfaces are being installed worldwide, even in regions with very high values of air temperature, leading to the need of evaluating the performance of monofilaments and thus, of testing their bending force at elevated temperatures. The aim of this paper is to use the DMA's advantage of testing at high temperatures, by using a new test method developed for measuring the bending force of monofilaments at room temperature and to evaluate the results obtained. For this purpose, six different LLDPE (Low Linear Density Polyethylene) monofilaments are tested at temperatures 25 degrees C, 50 degrees C and 80 degrees C and the bending force is measured. The DMA is used successfully on performing tests at high temperatures. Considering the results, an analysis of the bending behavior of LLDPE monofilaments depending on the temperature is done. All fibers show the same trends regarding this influence, with decreasing of the bending force while increasing the temperature

    Novel optimal temperature profile for acidification process of Lactobacillus bulgaricus and Streptococcus thermophilus in yoghurt fermentation using artificial neural network and genetic algorithm

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    The acidification behavior of Lactobacillus bulgaricus and Streptococcus thermophilus for yoghurt production was investigated along temperature profiles within the optimal window of 38-44 degrees C. For the optimal acidification temperature profile search, an optimization engine module built on a modular artificial neural network (ANN) and genetic algorithm (GA) was used. Fourteen batches of yoghurt fermentations were evaluated using different temperature profiles in order to train and validate the ANN sub-module. The ANN captured the nonlinear relationship between temperature profiles and acidification patterns on training data after 150 epochs. This served as an evaluation function for the GA. The acidification slope of the temperature profile was the performance index. The GA sub-module iteratively evolved better temperature profiles across generations using GA operations. The stopping criterion was met after 11 generations. The optimal profile showed an acidification slope of 0.06117 compared to an initial value of 0.0127 and at a set point sequence of 43, 38, 44, 43, and 39 degrees C. Laboratory evaluation of three replicates of the GA suggested optimum profile of 43, 38, 44, 43, and 39 degrees C gave an average slope of 0.04132. The optimization engine used (to be published elsewhere) could effectively search for optimal profiles of different physico-chemical parameters of fermentation processes

    Factors in organisational environmental management system implementation – Developed vs. Developing country contexts

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    Country specificities and national cultures influence Environmental Management Systems (EMS) implementation and pro-environmental behaviour in organisations. Previous studies have focused on organisations in developed or emerging economies, creating a need to establish the extent to which findings are applicable to developing counterparts. This paper presents EMS implementation from a developing country perspective, reporting on EMS implementation factors (drivers, benefits, barriers) affecting Nigerian organisations’ pro-environmental behaviour, by analysing questionnaire responses from 136 Nigerian organisational respondents. Most commonly cited drivers were ‘environmental concern’ and ‘desire for improved organisational efficiency’. Key barriers were ‘cost of implementation/budget barriers’ and ‘regulatory agency bureaucracy’. Key benefits were ‘reduced environmental accidents and improved site safety’, ‘enhanced corporate image’ and ‘more efficient resource use’. To situate findings within a global construct, results were compared with previous studies in more developed economies. EMS implementation factors differed from those in more developed economies. Plausible explanations for differences are discussed

    The path to global equity in mental health care in the context of COVID-19

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    The theme of the 2021 World Mental Health Day is “Mental Health in an Unequal World”, highlighting unequal access to mental health care across the world. This situation has been further worsened by governmental and public responses to the COVID-19 pandemic. The response of many high-income countries (HICs) and institutions to the pandemic has been the reverse of equity, exemplified by inequitable access to COVID-19 vaccines and widening inequities in wealth.1 A crucial consideration in this context is the imbalance in social and economic factors that shape onset and outcomes of mental health across communities and countries.2 Looking through a lens of equity, some individuals and populations need greater—not equal— intensity of mental health promotion, prevention, and treatment efforts because of the constellation of adversities, social marginalisation, and burden of ill health they experience

    Kinstate intervention in ethnic conflicts : Albania and Turkey compared

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    Albania and Turkey did not act in overtly irredentist ways towards their ethnic brethren in neighboring states after the end of communism. Why, nonetheless, did Albania facilitate the increase of ethnic conflict in Kosovo and Macedonia, while Turkey did not, with respect to the Turks of Bulgaria? I argue that kin-states undergoing transition are more prone to intervene in external conflicts than states that are not, regardless of the salience of minority demands in the host-state. The transition weakens the institutions of the kin-state. Experiencing limited institutional constraints, self-seeking state officials create alliances with secessionist and autonomist movements across borders alongside their own ideological, clan-based and particularistic interests. Such alliances are often utilized to advance radical domestic agendas. Unlike in Albania's transition environment, in Turkey there were no emerging elites that could potentially form alliances and use external movements to legitimize their own domestic existence or claims

    The Orexigenic Effect of Ghrelin Is Mediated through Central Activation of the Endogenous Cannabinoid System

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    INTRODUCTION Ghrelin and cannabinoids stimulate appetite, this effect possibly being mediated by the activation of hypothalamic AMP-activated protein kinase (AMPK), a key enzyme in appetite and metabolism regulation. The cannabinoid receptor type 1 (CB1) antagonist rimonabant can block the orexigenic effect of ghrelin. In this study, we have elucidated the mechanism of the putative ghrelin-cannabinoid interaction. METHODS The effects of ghrelin and CB1 antagonist rimonabant in wild-type mice, and the effect of ghrelin in CB1-knockout animals, were studied on food intake, hypothalamic AMPK activity and endogenous cannabinoid content. In patch-clamp electrophysiology experiments the effect of ghrelin was assessed on the synaptic inputs in parvocellular neurons of the hypothalamic paraventricular nucleus, with or without the pre-administration of a CB1 antagonist or of cannabinoid synthesis inhibitors. RESULTS AND CONCLUSIONS Ghrelin did not induce an orexigenic effect in CB1-knockout mice. Correspondingly, both the genetic lack of CB1 and the pharmacological blockade of CB1 inhibited the effect of ghrelin on AMPK activity. Ghrelin increased the endocannabinoid content of the hypothalamus in wild-type mice and this effect was abolished by rimonabant pre-treatment, while no effect was observed in CB1-KO animals. Electrophysiology studies showed that ghrelin can inhibit the excitatory inputs on the parvocellular neurons of the paraventricular nucleus, and that this effect is abolished by administration of a CB1 antagonist or an inhibitor of the DAG lipase, the enzyme responsible for 2-AG synthesis. The effect is also lost in the presence of BAPTA, an intracellular calcium chelator, which inhibits endocannabinoid synthesis in the recorded parvocellular neuron and therefore blocks the retrograde signaling exerted by endocannabinoids. In summary, an intact cannabinoid signaling pathway is necessary for the stimulatory effects of ghrelin on AMPK activity and food intake, and for the inhibitory effect of ghrelin on paraventricular neurons

    Teaching tobacco dependence treatment and counseling skills during medical school: rationale and design of the Medical Students helping patients Quit tobacco (MSQuit) group randomized controlled trial

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    INTRODUCTION: Physician-delivered tobacco treatment using the 5As is clinically recommended, yet its use has been limited. Lack of adequate training and confidence to provide tobacco treatment is cited as leading reasons for limited 5A use. Tobacco dependence treatment training while in medical school is recommended, but is minimally provided. The MSQuit trial (Medical Students helping patients Quit tobacco) aims to determine if a multi-modal and theoretically-guided tobacco educational intervention will improve tobacco dependence treatment skills (i.e. 5As) among medical students. METHODS/DESIGN: 10 U.S. medical schools were pair-matched and randomized in a group-randomized controlled trial to evaluate whether a multi-modal educational (MME) intervention compared to traditional education (TE) will improve observed tobacco treatment skills. MME is primarily composed of TE approaches (i.e. didactics) plus a 1st year web-based course and preceptor-facilitated training during a 3rd year clerkship rotation. The primary outcome measure is an objective score on an Objective Structured Clinical Examination (OSCE) tobacco-counseling smoking case among 3rd year medical students from schools who implemented the MME or TE. DISCUSSION: MSQuit is the first randomized to evaluate whether a tobacco treatment educational intervention implemented during medical school will improve medical students\u27 tobacco treatment skills. We hypothesize that the MME intervention will better prepare students in tobacco dependence treatment as measured by the OSCE. If a comprehensive tobacco treatment educational learning approach is effective, while also feasible and acceptable to implement, then medical schools may substantially influence skill development and use of the 5As among future physicians. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved

    Diagnosis and Complications of Cushing's Syndrome: A Consensus Statement

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    In October 2002, a workshop was held in Ancona, Italy, to reach a Consensus on the management of Cushing's syndrome. The workshop was organized by the University of Ancona and sponsored by the Pituitary Society, the European Neuroendocrine Association, and the Italian Society of Endocrinology. Invited international participants included almost 50 leading endocrinologists with specific expertise in the management of Cushing's syndrome. The consensus statement on diagnostic criteria and the diagnosis and treatment of complications of this syndrome reached at the workshop is hereby summarized

    Ghrelin Modulates the fMRI BOLD Response of Homeostatic and Hedonic Brain Centers Regulating Energy Balance in the Rat

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    The orexigenic gut-brain peptide, ghrelin and its G-protein coupled receptor, the growth hormone secretagogue receptor 1a (GHS-R1A) are pivotal regulators of hypothalamic feeding centers and reward processing neuronal circuits of the brain. These systems operate in a cooperative manner and receive a wide array of neuronal hormone/transmitter messages and metabolic signals. Functional magnetic resonance imaging was employed in the current study to map BOLD responses to ghrelin in different brain regions with special reference on homeostatic and hedonic regulatory centers of energy balance. Experimental groups involved male, ovariectomized female and ovariectomized estradiol-replaced rats. Putative modulation of ghrelin signaling by endocannabinoids was also studied. Ghrelin-evoked effects were calculated as mean of the BOLD responses 30 minutes after administration. In the male rat, ghrelin evoked a slowly decreasing BOLD response in all studied regions of interest (ROI) within the limbic system. This effect was antagonized by pretreatment with GHS-R1A antagonist JMV2959. The comparison of ghrelin effects in the presence or absence of JMV2959 in individual ROIs revealed significant changes in the prefrontal cortex, nucleus accumbens of the telencephalon, and also within hypothalamic centers like the lateral hypothalamus, ventromedial nucleus, paraventricular nucleus and suprachiasmatic nucleus. In the female rat, the ghrelin effects were almost identical to those observed in males. Ovariectomy and chronic estradiol replacement had no effect on the BOLD response. Inhibition of the endocannabinoid signaling by rimonabant significantly attenuated the response of the nucleus accumbens and septum. In summary, ghrelin can modulate hypothalamic and mesolimbic structures controlling energy balance in both sexes. The endocannabinoid signaling system contributes to the manifestation of ghrelin’s BOLD effect in a region specific manner. In females, the estradiol milieu does not influence the BOLD response to ghrelin
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