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关键词： Precipitable Water   Water Vapor   Cloud Computing   Meteorology   Atmospheric convection   Global Navigation Satellite System   Network   tropics  

摘要： The complex interactions between water vapor fields and deep atmospheric convection remain one of the outstanding problems in tropical meteorology. The lack of high spatial-temporal resolution, all-weather observations in the tropics has hampered progress. Numerical models have difficulties, for example, in representing the shallow-to-deep convective transition and the diurnal cycle of precipitation. Global Navigation Satellite System (GNSS) meteorology, which provides all-weather, high-frequency (5 min), precipitable water vapor estimates, can help. The Amazon Dense GNSS Meteorological Network experiment, the first of its kind in the tropics, was created with the aim of examining water vapor and deep convection relationships at the mesoscale. This innovative, Brazilian-led international experiment consisted of two mesoscale (100 km x 100 km) networks: 1) a 1-yr (April 2011-April 2012) campaign (20 GNSS meteorological sites) in and around Manaus and 2) a 6-week (June 2011) intensive campaign (15 GNSS meteorological sites) in and around Belem, the latter in collaboration with the Cloud Processes of the Main Precipitation Systems in Brazil: A Contribution to Cloud-Resolving Modeling and to the Global Precipitation Measurement (CHUVA) Project in Brazil. Results presented here from both networks focus on the diurnal cycle of precipitable water vapor associated with sea-breeze convection in Belem and seasonal and topographic influences in and around Manaus. Ultimately, these unique observations may serve to initialize, constrain, or validate precipitable water vapor in high-resolution models. These experiments also demonstrate that GNSS meteorology can expand into logistically difficult regions such as the Amazon. Other GNSS meteorology networks presently being constructed in the tropics are summarized.

关键词： CARDIOPULMONARY system   PULMONARY gas exchange   ARTIFICIAL respiration   HEART beat   OBSTRUCTIVE lung diseases   EXERCISE  

关键词： image classification   training samples   maximum likelihood classification   support vector machine   active learning  

摘要： Supervised classification is the commonly used method for extracting ground information from images. However, for supervised classification, the selection and labelling of training samples is an expensive and time-consuming task. Recently, automatic information indexes have achieved satisfactory results for indicating different land-cover classes, which makes it possible to develop an automatic method for labelling the training samples instead of manual interpretation. In this paper, we propose a method for the automatic selection and labelling of training samples for high-resolution image classification. In this way, the initial candidate training samples can be provided by the information indexes and open-source geographical information system (GIS) data, referring to the representative land-cover classes: buildings, roads, soil, water, shadow, and vegetation. Several operations are then applied to refine the initial samples, including removing overlaps, removing borders, and semantic constraints. The proposed sampling method is evaluated on a series of high-resolution remote sensing images over urban areas, and is compared to classification with manually labeled training samples. It is found that the proposed method is able to provide and label a large number of reliable samples, and can achieve satisfactory results for different classifiers. In addition, our experiments show that active learning can further enhance the classification performance, as active learning is used to choose the most informative samples from the automatically labeled samples.

关键词： Adamantinomatous craniopharyngioma   Papillary craniopharyngioma   Rathke cleft cyst   Beta-catenin   CTNNB1   BRAF  

摘要： Purpose To assess the role of high sensitivity next-generation sequencing (NGS) of CTNNB1 for the diagnosis of adamantinomatous craniopharyngiomas (aCPs) and of BRAF for that of papillary CPs (pCPs) in routinely processed surgical samples of nonadenomatous sellar lesions. Methods Forty-five cases of patients operated for nonadenomatous masses of the sellar region between 2004 and 2014 were retrieved from the files of the Anatomic Pathology unit of the Bellaria Hospital in Bologna, Italy. BRAF and CTNNB1 mutation status was analyzed by NGS in samples smaller than 1 cm(3) and histological re-evaluation was performed on all cases. Results CTNNB1 mutation analysis showed a sensitivity of 86.7 % and a specificity of 96.2 % for the diagnosis of aCPs. The specificity increased to 100 % considering that in one case, initially classified as a non-CP lesion (xanthogranuloma), the identification of a CTNNB1 S47R lead to histological re-evaluation and reclassification of the lesion as aCP. BRAF mutation analysis had a sensitivity of 76.9 % and a specificity of 96.4 % for the diagnosis of pCPs. The specificity increased to 100 % considering that in one case, initially classified as a Rathke cyst, the identification of BRAF V600E lead to histological re-evaluation and reclassification of the lesion as pCP. Conclusions This study confirms the diagnostic relevance of the molecular alterations recently identified in aCPs and pCPs and shows how the identification of BRAF and CTNNB1 mutations can be instrumental for the proper classification of samples that contain limiting amounts of diagnostic lesional tissue.

关键词： Ecological systems   public housing   adolescents   substance use   delinquency  

摘要： The increased risk for substance use and delinquency among adolescents of color has been partially attributed to increased exposure to daily hassles. Although a certain number of hassles are normative, especially among family and peers, adolescents of color experience more stressors in their neighborhood or directly related to fewer resources than their White counterparts. These hassles may interact across ecological systems to impact behavioral outcomes among adolescents. This may be especially true for young people living in public housing. Based on ecological systems theory, this study tests the relationship between experiences of hassles across multiple ecological levels and problem behaviors in a sample of 315 ethnically diverse early adolescents (M-age = 12;51% female) living in public housing neighborhoods in two large metropolitan areas in the United States. A positive relationship was found between family hassles and both substance use and delinquency, as well as between school hassles and substance use. When the interactions between family, peer, school, and neighborhood/resource hassles were considered, five statistically significant interactions were found. The study results reinforce the role of contextual factors, such as living in low-income neighborhoods and the complexity of hassles interacting at multiple levels of a young person's daily ecology, on adolescent outcomes.

关键词： 临床医师   检验医师   培养   检验医学  

摘要： 检验医师主要发挥检验与临床沟通的桥梁作用,临床培训是检验医师培养的重要环节。因此,临床医师在检验医师培养中也发挥重要作用。临床医师了解检验医师培养的目的和意义、转变观念、在临床带教中对检验医师采取有针对性的措施和方法是重要的环节。检验医师培养需要临床医师和医学检验专家共同努力。

关键词： 食品   微生物   污染   分析  

摘要： 由于食品中有大量的营养成分,所以为微生物的生长创造了良好的生存环境,也因此使食品在加工过程中容易受到微生物的污染,现阶段,这种食品污染已成为广大消费者和生产者共同关注的热点话题,食品污染为人们的身体健康带来了巨大隐患,尤其是现在社会中广泛出现的食物中毒问题,造成了大多数人们得了食源性疾病,毒物会导致集体正常的生理工程造成破坏,从而引发集体中毒,甚至会导致身体死亡的可怕性毒物。那么,如何有效控制这种污染呢。

关键词： 标本制备   实验室   医院   质量控制  

摘要： 目的对不合格临床检验标本进行综合分析，探讨原因及发生的比例，达到提高标本分析前质量的目的。方法采用回顾性研究方法，分析2012年3月至2013年2月广州军区广州总医院分析前不合格的血液标本1728例、尿液标本829例、粪便标本372例，运用统计学方法对数据进行综合分析。结果血液、尿液、粪便标本不合格率分别是3．71‰、3．61‰、11．53‰。不合格原因：血液标本以标本凝块最常见占3．42‰，其中又以紫色EDTA-K：管发生标本凝块的风险最高（x^2=248．779，P〈0．001）；尿液不合格标本主要原因是量少占2．08‰；粪便不合格主要原因是无标本占7．19‰。结论及时反馈结果给临床医护人员，共同建立完善的控制标本不合格率的制度，降低标本不合格率，确保分析前质量。

关键词： 农民工   工资率   劳动合同形式   分位数回归  

摘要： 本文基于国家卫生计生委流动人口动态监测调查数据,依托OLS方法检验劳动合同形式对农民工工资率的影响,并借助分位数回归方法细致深入地诠释其作用机制。研究结果表明,签订劳动合同将会显著提升农民工的工资率,有固定期限的劳动合同对农民工,尤其是对中低收入的农民工,工资促进效应更为突出。

关键词： Switching costs   Changed preferences   Contract design   Equilibrium price  

摘要： This paper compares three contract forms, including short-term contract with price discrimination, short-term contract without price discrimination, and long-term contract with price commitment for consumers with switching costs and changed preferences. We find that long-term contract generates the largest profit for firms. Moreover, we find that switching costs make the market more competitive when consumers have changed preferences, and the higher the switching costs, the more competitive. Our theory combines linear-city duopoly and switching-cost model and the results are consistent with literature, for example price commitment is valuable. Our findings shed light on the practice of different forms of dynamic pricing in various industries including telecommunication industry and airline industry. (C) 2015 Elsevier B.V. All rights reserved.