Experimental investigation of air flow and temperature distribution in deep urban canyons for natural ventilation purposes

Detailed experiments have been carried out in a deep canyon in Athens during the summer period. The aim of the experimental campaign was first to evaluate the potential of natural ventilation in the urban environment and second to better understand the air flow and thermal phenomena in deep urban canyons. Extensive measurements of the surface and air temperature as well as the wind speed in the middle and close to the canyon façades have been measured in a continuous basis. In parallel, the undisturbed temperature, wind speed and direction above the canyon have been measured as well. Measurements of the airflow rate in single side and cross ventilation configurations have been carried out using tracer gas techniques, in a naturally ventilated building located in the canyon. It is found that the potential of natural ventilation for both single side and cross ventilation configurations in buildings located inside urban canyons, is seriously reduced. It is estimated, that in the specific canyon, the airflow rate for single side and cross ventilation configurations, is reduced by 82 and 68%, respectively compared to an undisturbed location. The mechanism of the air flow and temperature distribution inside the canyon is extensively analysed and the specific phenomena that determine the wind speed and direction inside the canyon are described in details. © 2005 Elsevier B.V. All rights reserved

Co-existence of Morgagni’s cyst with a twisted vas aberrans and “bell clapper” deformity in a 15-year-old boy: a case report

Abstract Background The testicular appendix is a residual of the paramesonephric and mesonephric duct, most commonly found close to the superior pole of the epididymis as Morgagni’s cyst. Torsion of such cysts is a common event in children, and the patient usually presents with a palpable testis with a tender mass in its upper pole. The co-existence of two or more appendices is very rare. In addition to the fact that Morgagni’s cyst was the non-twisted one and vas aberrans was, made clinical and radiological diagnosis difficult. Case presentation Our patient, a 15-year-old boy, presented with persistent pain in the right scrotum, a significant palpable mass accompanied by vomiting. Upon surgical exploration, a large dark cyst was found located on the right side of the right testicle with a 720-degree torsion. The cyst was straightened and excised along with a Morgagni’s cyst. The testis was fixed in the right hemiscrotum due to a “bell clapper” deformity that was also a finding. Conclusions Pathological findings were consistent with a twisted cyst of a testicular appendix (vas aberrans). Co-existence of two or more appendices is very rare in addition to the fact that Morgagni’s cyst was the non-twisted one. Usually and in very few cases, a second appendix is found randomly, during surgical exploration for acute scrotum due to torsion of Morgagni’s cyst

General anaesthesia versus local anaesthesia for carotid surgery (GALA): a multicentre, randomised controlled trial

BACKGROUND: The effect of carotid endarterectomy in lowering the risk of stroke ipsilateral to severe atherosclerotic carotid-artery stenosis is offset by complications during or soon after surgery. We compared surgery under general anaesthesia with that under local anaesthesia because prediction and avoidance of perioperative strokes might be easier under local anaesthesia than under general anaesthesia. METHODS: We undertook a parallel group, multicentre, randomised controlled trial of 3526 patients with symptomatic or asymptomatic carotid stenosis from 95 centres in 24 countries. Participants were randomly assigned to surgery under general (n=1753) or local (n=1773) anaesthesia between June, 1999 and October, 2007. The primary outcome was the proportion of patients with stroke (including retinal infarction), myocardial infarction, or death between randomisation and 30 days after surgery. Analysis was by intention to treat. The trial is registered with Current Control Trials number ISRCTN00525237. FINDINGS: A primary outcome occurred in 84 (4.8%) patients assigned to surgery under general anaesthesia and 80 (4.5%) of those assigned to surgery under local anaesthesia; three events per 1000 treated were prevented with local anaesthesia (95% CI -11 to 17; risk ratio [RR] 0.94 [95% CI 0.70 to 1.27]). The two groups did not significantly differ for quality of life, length of hospital stay, or the primary outcome in the prespecified subgroups of age, contralateral carotid occlusion, and baseline surgical risk. INTERPRETATION: We have not shown a definite difference in outcomes between general and local anaesthesia for carotid surgery. The anaesthetist and surgeon, in consultation with the patient, should decide which anaesthetic technique to use on an individual basis. FUNDING: The Health Foundation (UK) and European Society of Vascular Surgery