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151.
Montagna MT De Giglio O Napoli C Lovero G Caggiano G Delia M Pastore D Santoro N Specchia G 《International journal of molecular sciences》2012,13(1):774-787
The aim of this multicenter prospective study was to evaluate the incidence of invasive fungal infections (IFIs) in adult and pediatric patients with hematologic malignancies, involving nine nosocomial facilities in Southern Italy over a period of 18 months. Furthermore, results of an environmental microbial surveillance routinely carried out in some of the enrolled hospitals are reported. A total of 589 onco-hematological patients were enrolled and 27 IFIs were documented. The main infections were caused by yeasts, more than filamentous fungi (overall incidence of 2.7% and 1.9%, respectively). The yeasts were mainly represented by Candida spp. (87.5%), all isolated by blood cultures; C. parapsilosis was the most common species. Among mould infections, the most frequent site was the lung, with regard to aspergillosis (81.8%). In six of the 10 patients with suspected aspergillosis, the diagnosis was made by the detection of galactomannan and (1,3)-β-d-glucan antigens. The microbiological surveillance carried out on 156 air, 312 water and 312 surface samples revealed low environmental contamination: Alternaria alternata was the only fungus isolated from two surface samples. Our data, especially the low occurrence of filamentous fungi, suggest a particular local epidemiology. Further studies are needed to confirm this microbiological trend in onco-hematological patients in Southern Italy, the results of which might be helpful to improve the management of these patients. 相似文献
152.
Phase change memory materials store information through their reversible transitions between crystalline and amorphous states. For typical metal chalcogenide compounds, their phase transition properties directly impact critical memory characteristics and the manipulation of these is a major focus in the field. Here, we discuss recent work that explores the tuning of such properties by scaling the materials to nanoscale dimensions, including fabrication and synthetic strategies used to produce nanoscale phase change memory materials. The trends that emerge are relevant to understanding how such memory technologies will function as they scale to ever smaller dimensions and also suggest new approaches to designing materials for phase change applications. Finally, the challenges and opportunities raised by integrating nanoscale phase change materials into switching devices are discussed. 相似文献
153.
Background
Nutrition is often a casualty of the busy work day for physicians. We aimed to explore physicians' views of their nutrition in the workplace including their perceptions of the impact of inadequate nutrition upon their personal wellness and their professional performance. 相似文献154.
Anca-Stefania Mesaros Sorina Sava Delia Mitrea Cristina Gasparik Camelia Alb Michaela Mesaros 《Journal of Adhesion Science and Technology》2013,27(20):2256-2279
Esthetic dentistry imposes several demands on the artistic abilities of the dentist, and knowledge of the underlying scientific principles of tooth color is considered to be essential by Sikri. The supervised classification methods, such as the artificial neural networks, the support vector machines, and also the Bayesian classifier, and the feature selection methods, such as decision trees, genetic algorithms and neural networks, as well as independent component analysis combined with least square support vector machines, were applied successfully in the medical field but were less implemented in the dental analysis domain. This study was conducted on extracted premolars from people who required orthodontic treatment. Data gathering was done using spectrophotometric recordings of tooth color parameters before and after accelerated bleaching, staining, and control procedures on extracted teeth on which was simulated orthodontic treatment. Comparison between data mining techniques and classical statistical interpretation of data was done. The results demonstrated the usefulness of these innovating data assessment techniques in the dental field. 相似文献
155.
156.
Marco Ajmone Marsan Luca Chiaraviglio Delia Ciullo Michela Meo 《Computer Networks》2013,57(17):3276-3290
In this paper we study base station sleep modes that, by reducing power consumption in periods of low traffic, improve the energy efficiency of cellular access networks. We assume that when some base stations enter sleep mode, radio coverage and service provisioning are provided by the base stations that remain active, so as to guarantee that service is available over the whole area at all times. This may be an optimistic assumption in the case of the sparse base station layouts typical of rural areas, but is, on the contrary, a realistic hypothesis for the dense layouts of urban areas, which consume most of the network energy. 相似文献
157.
Roosa Mark W.; Zeiders Katharine H.; Knight George P.; Gonzales Nancy A.; Tein Jenn-Yun; Saenz Delia; O'Donnell Megan; Berkel Cady 《Canadian Metallurgical Quarterly》2011,47(2):527
Mexican American adolescents have higher rates of externalizing problems than their peers from other ethnic and racial groups. To begin the process of understanding factors related to externalizing problems in this population, this study used the social development model (SDM) and prospective data across the transition to junior high school from 750 diverse Mexican American families. In addition, the authors examined whether familism values provided a protective effect for relations within the model. Results showed that the SDM worked well for this sample. As expected, association with deviant peers was the primary predictor of externalizing behaviors. There was support for a protective effect in that adolescents with higher familism values had slower rates of increase in association with deviant peers from 5th to 7th grades than those with lower familism values. Future research needs to determine whether additional culturally appropriate modifications of the SDM would increase its usefulness for Mexican American adolescents. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
158.
159.
Claire Joannis‐Cassan Marie‐Line Delia Jean‐Pierre Riba 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2005,80(1):99-106
Limiting factors induced by the formation of a biofilm on the hydrocarbon's surface during in‐situ bioremediation were identified. A liquid–liquid system (hydrocarbon–aqueous solution) and a device made of six fixed‐bed columns packed with sand were successively used on a laboratory‐scale. In the liquid–liquid system, it was shown that biofilm growth was limited by the diffusion of both oxygen and hydrocarbon within the biofilm. At the end of growth, the biofilm thickness reached 80 ± 20µm. In the fixed‐bed columns, additional difficulties were observed. First, distribution of oxygen in the deepest part of the sand was difficult: from 84 to 100% of the biofilm growth occurred in the upper two‐thirds of the sand. Then, the surface of the hydrocarbon available for microorganisms was found to be a limiting factor for the biofilm's development. Copyright © 2004 Society of Chemical Industry 相似文献
160.
Demonstrates that the rebound effect of thought suppression (D. M. Wegner, 1989) has an analog in the experience of somatic discomfort. During a cold-pressor pain induction, 63 Ss were instructed either to concentrate on their room at home (distraction), to pay close attention to their hand sensations (monitoring), or to remove awareness of those sensations from mind (suppression). Two minutes of postpressor pain ratings showed that monitoring produced the most rapid recovery from the pain and that suppression produced the slowest. Suppression also contaminated the interpretation of a subsequent somatic stimulation; later in the experimental hour, Ss who had suppressed their cold-pressor discomfort rated an innocuous vibration as more unpleasant than did other Ss. The strategies are discussed for their necessarily distinct processes of goal evaluation and their possibly differential drain on perceived coping capacities. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献