702 research outputs found

    Müllerian Serous Cystadenoma of the Scrotum Following Orchiopexy

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    A 24-year-old man presented himself with a nodular lesion of about 1 cm diameter at the site of a previous orchiopexy associated with surgery for cryptorchism. Histopathology revealed the lesion to be adenomatous and confined to the scrotum. Histological and immunohistological features were not consistent neither with median raphe cysts or cutaneous adenomas nor with the intrascrotal adenomas of the rete testis, epididymis, nor with (malignant) mesotheliomas. However, the lesion did compare well with serous (papillary) cystadenomas of the testis or paratestis. These adenomas are thought to originate in remnants of the Müllerian system or of peritoneal lining altered by Müllerian metaplasia. This implies that the scrotal adenoma may have developed from an implant of such elements during orchiopexy 14 years ago. Complete excision of the lesion appears to be an adequate therapy

    Numerical and Experimental Study of Natural Convection Air Flow in a Solar Tower Dryer

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    This work focuses on the study of the flow of air in natural convection in a solar tower of small size. The behavior of air in the tower, considered as a solar dryer, provides information on the amount of heat absorbed by the air upon entry into the collector. A theoretical approach allows us to theoretically simulate the flow by using a mathematical model characterizing the physical parameters of the system during a daily sunshine. An analysis of this phenomenon is made and results are obtained

    Measurement of Intrinsic Dirac Fermion Cooling on the Surface of the Topological Insulator Bi_2Se_3 Using Time-Resolved and Angle-Resolved Photoemission Spectroscopy

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    We perform time- and angle-resolved photoemission spectroscopy of a prototypical topological insulator (TI) Bi_2Se_3 to study the ultrafast dynamics of surface and bulk electrons after photoexcitation. By analyzing the evolution of surface states and bulk band spectra, we obtain their electronic temperature and chemical potential relaxation dynamics separately. These dynamics reveal strong phonon-assisted surface-bulk coupling at high lattice temperature and total suppression of inelastic scattering between the surface and the bulk at low lattice temperature. In this low temperature regime, the unique cooling of Dirac fermions in TI by acoustic phonons is manifested through a power law dependence of the surface temperature decay rate on carrier density

    Dzieci sieci 2.0

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    S\u142owa kluczowe: kompetencje komunikacyjne m\u142odzie\u17cy, edukacja medialna - gimnazjum, szkolne programy nauczania, netnografia, internet a uczniowie gimnazj\uf3

    Optical and Thermal Performance Analysis of a Steady Spherical Collector with a Crescent-shaped Rotating Absorber

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    In this paper, optical analysis of spherical concentrator is made to determine the local and the global geometric concentration, as knowing the geometric concentration of a system can help predict what temperatures can possibly be obtained with it.This leads to conclude that spherical collectors may produce higher temperatures than parabolic trough, and they could even be sharply improved by using a mixt cylindrical and cavity (or flat) absorber. A craft prototype of a steady spherical concentrator made with concreteand having a smooth inner surface mapped with mirror tape is presented. Its absorber is made with blacken steel sheets and shaped like a moon crescent to be aligned with the declination plan and to avoid motorization for the tracking of the sun from East to West. Experimental measurements lead to temperatures reaching 686°C on the curve of the least diffusion, and 252°C in the absorber oven-like reservoir. Overall, the resultsuggests higher potentialities of spherical collectors,which also show possibility of use with much reduced tracking system and less vulnerability to bad weather

    Frailty and physical performance in the context of extreme poverty:a population-based study of older adults in rural Burkina Faso

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    Background: Little is known about the prevalence of frailty and about normal values for physical performance among older individuals in low-income countries, in particular those in sub-Saharan Africa. We describe the prevalence of phenotypic frailty, and values and correlates of several physical performance measures in a cohort of middle-aged and older people living in rural Burkina Faso, one of the world's poorest communities. Methods: We analysed data collected from participants aged over 40 in Nouna district, Burkina Faso. We measured handgrip strength, four metre walk speed, chair rise time, and derived the Fried frailty score based on grip strength, gait speed, body mass index, self-reported exhaustion, and physical activity. Frailty and physical performance indicators were then correlated with health and sociodemographic variables including comorbid disease, marital status, age, sex, wealth and activity impairment. Results: Our sample included 2973 individuals (1503 women), mean age 54 years. 1207 (43%) were categorised as non-frail, 1324 (44%) as prefrail, 212 (7%) as frail, and 167 (6%) were unable to complete all five frailty score components. Lower grip strength, longer chair stand time, lower walk speed and prevalence of frailty rose with age. Frailty was more common in women than men (8% vs 6%, p=0.01) except in those aged 80 and over. Frailty was strongly associated with impairment of activities of daily living and with lower wealth, being widowed, diabetes mellitus, hypertension, and self-reported diagnoses of tuberculosis or heart disease. With the exception of grip strength, which was higher in women than prior international normative values, women had greater deficits than men in physical performance. Conclusions: Phenotypic frailty and impaired physical performance were associated as expected with female sex, co-morbidities, increasing age and impaired activities of daily living. These results support the use of frailty measurements for classification of ageing related syndromes in this setting.GH is supported by a Wellcome Trust/Royal Society Sir Henry Dale fellowship, award number 210479/Z/18/Z. Support for the CRSN Heidelberg Aging Study and for TB was provided by the Alexander von Humboldt Foundation through the Alexander von Humboldt Professor award to Till Bärnighausen, funded by the German Federal Ministry of Education and Research. JMG is supported by Grant Number T32 AI007433 from the National Institute of Allergy and Infectious Diseases. The contents of this study are solely the responsibility of the authors and do not necessarily represent the official views of the NIH. MDW acknowledges support from the NIHR Newcastle Biomedical Research Centre. CFP acknowledges support from the ANU Futures Scheme

    The need for allele mining: perspectives of the System-wide Genetic Resources Programme (SGRP)

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    The SGRP is a consortium of all CGIAR gene banks. These banks aim to (1) conserve diversity efficiently, including and especially rare alleles and genotypes; (2) ensure efficient use of collection by delivering appropriately selected subsets of germplasm to users, maximizing the chance of giving users the set of alleles or genotypes that they need; and (3) ensure that the entire collection remains available for use. The SGRP exists to ensure a consistent, integrated, system-wide approach to the efficient achievement of these goals

    Performance of EUS-FNA for mediastinal lymphadenopathy: impact on patient management and costs in low-volume EUS centers

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    BACKGROUND: Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) of mediastinal lymphadenopathy has been shown to be a valuable diagnostic tool in high-volume EUS centers (≥ 50 mediastinal EUS-FNA/endoscopist/year). Our goal was to assess the diagnostic accuracy of EUS-FNA and its impact on clinical management and costs in low-volume EUS centers ( <50 mediastinal EUS-FNA/endoscopist/year). METHODS: Consecutive patients referred to two Dutch endoscopy centers in the period 2002-2008 for EUS-FNA of mediastinal lymphadenopathy were reviewed. The gold standard for a cytological diagnosis was histological confirmation or clinical follow-up of more than 6 months with repeat imaging. The impact of EUS-FNA on clinical management was subdivided into a positive impact by providing (1) adequate cytology that influenced the decision to perform surgery or (2) a diagnosis of a benign inflammatory disorder, and a negative impact which was subdivided into (1) false-negative or inconclusive cytology or (2) an adequate cytological diagnosis that did not influence patient management. Costs of an alternative diagnostic work-up without EUS-FNA, as established by an expert panel, were compared to costs of the actual work-up. RESULTS: In total, 213 patients (71% male, median age= 61 years, range = 23-88 years) underwent EUS-FNA. Sensitivity, specificity, and negative and positive predictive values were 89%, 100%, 80%, and 100%, respectively. EUS-FNA had a positive impact on clinical management in 84% of cases by either influencing the decision to perform surgery (49%) or excluding malignant lymphadenopathy (35%), and a negative impact in 7% of cases because of inadequate (3%) or false-negative (4%) cytology. In 9% of cases, EUS-FNA was performed without an established indication. Two nonfatal perforations occurred (0.9%). Total cost reduction was €100,593, with a mean cost reduction of €472 (SD = €607) per patient. CONCLUSIONS: Mediastinal EUS-FNA can be performed in low-volume EUS centers without compromising diagnostic accuracy. Moreover, EUS-FNA plays an important role in the management of patients with mediastinal lymphadenopathy and reduces total diagnostic cost
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