321 research outputs found

    Zoo-technical application of Ground Source Heat Pumps: a pilot case study

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    Ground Source Heat Pumps are energy-efficient HVAC systems usually adopted in residential and commercial buildings. However the control of the thermal environment is required not only in spaces occupied by people, but also in intensive breeding farms, in order to maintain healthy conditions and to increase productivity. In the Italian livestock breedings, heating is usually provided by means of gas or Diesel burners directly installed in the stable. An important part of the heating load is due to the large ventilation rates required for the livestock wellbeing. Cooling is either absent or achieved by evaporative systems that also increase the humidity level in the stables, thus requiring even larger ventilation rates. Therefore the applicability of geothermal heating and cooling in breeding farms was analysed in a research project co-funded by the Lombardy Region and the Italian Ministry of Research and Education. A pilot system for heating, cooling and ventilation was designed and installed in a piglets room at the Experimental and Didactic Zoo-technical Center of the University of Milan. Five Borehole Heat Exchangers (BHEs), installed down to a depth of 60 meters into an alluvial aquifer, were coupled with a Ground Source Heat Pump. The heat pump provides heating and cooling to an Air Handling Unit, including a Heat Recovery system. A monitoring system was installed in order to measure comfort conditions in the piglet room, operating conditions and energy consumption of the HVAC system, together with the spreading of the thermal plume in the ground. In this paper the results of a monitoring campaign carried out in a typical winter period are presented and discussed. The overall energy efficiency of the system, expressed in terms of a COP, results to be equal to 4.04. A comparison between the pilot HVAC system and a traditional one is also carried out, showing that the proposed solution can provide over 40% primary energy saving. Following, cost savings in energy bills for farmers are found, although the ratio between electricity cost and fuel cost is a key parameter

    Restless Legs Syndrome: Known Knowns and Known Unknowns

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    Although restless legs syndrome (RLS) is a common neurological disorder, it remains poorly understood from both clinical and pathophysiological perspectives. RLS is classified among sleep-related movement disorders, namely, conditions characterized by simple, often stereotyped movements occurring during sleep. However, several clinical, neurophysiological and neuroimaging observations question this view. The aim of the present review is to summarize and query some of the current concepts (known knowns) and to identify open questions (known unknowns) on RLS pathophysiology. Based on several lines of evidence, we propose that RLS should be viewed as a disorder of sensorimotor interaction with a typical circadian pattern of occurrence, possibly arising from neurochemical dysfunction and abnormal excitability in different brain structures

    Essential role of ICAM-1 in aldosterone-induced atherosclerosis.

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    OBJECTIVE: Elevated aldosterone is associated with increased risk of atherosclerosis complications, whereas treatment with mineralocorticoid receptor (MR) antagonists decreases the rate of cardiovascular events. Here we test the hypothesis that aldosterone promotes early atherosclerosis by modulating intercellular adhesion molecule-1 (ICAM-1) expression and investigate the molecular mechanisms by which aldosterone regulates ICAM-1 expression. METHODS AND RESULTS: Apolipoprotein-E (ApoE)-/- mice fed an atherogenic diet and treated with aldosterone for 4weeks showed increased vascular expression of ICAM-1, paralleled by enhanced atherosclerotic plaque size in the aortic root. Moreover, aldosterone treatment resulted in increased plaque lipid and inflammatory cell content, consistent with an unstable plaque phenotype. ApoE/ICAM-1 double knockout (ApoE-/-/ICAM-1-/-) littermates were protected from the aldosterone-induced increase in plaque size, lipid content and macrophage infiltration. Since aldosterone is known to regulate ICAM-1 transcription via MR in human endothelial cells, we explored MR regulation of the ICAM-1 promoter. Luciferase reporter assays performed in HUVECs using deletion constructs of the human ICAM-1 gene promoter showed that a region containing a predicted MR-responsive element (MRE) is required for MR-dependent transcriptional regulation of ICAM-1. CONCLUSIONS: Pro-atherogenic effects of aldosterone are mediated by increased ICAM-1 expression, through transcriptional regulation by endothelial MR. These data enhance our understanding of the molecular mechanism by which MR activation promotes atherosclerosis complications
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