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关键词： 塔式起重机   平衡臂   功能原理   检验要求   起重量限制器  

摘要： 塔式起重机的平衡臂对塔式起重机的安全极为重要,应高度重视其检验检测,切不可粗心大意。文章对塔式起重机平衡臂的作用、功能及检验要求进行了探讨。

关键词： Oil sands reclamation   Spatial variation   Aspen   Nutrient availability   Soil microbial properties   Extracellular enzyme activity  

摘要： Examining the spatial interactions between above and belowground components of terrestrial ecosystems can give meaningful insight into the ecological processes happening at different scales. Understanding spatial dependence in these processes may help to evaluate reclamation success which is crucial for future management of such areas. The aim of this study was to measure the spatial patterns of soil biogeochemical properties in a young aspen stand reclaimed after oil sands extraction and to evaluate how the patterns were related to nutrient availability. Samples were collected from a 14-year old reclaimed site using a spatially explicit protocol with a minimum resolution of 0.5 m. Field-measured variables included forest floor depth and mass, tree cluster (canopy overlap), distance to nearest tree, and resin available nutrients. Soil microbial properties including microbial biomass C and N, basal respiration, and extracellular enzyme activity were measured during an eight-week laboratory incubation experiment. Geo-statistics were applied to examine the spatial patterns and model the space effect. A fine scale (<10 m) spatial pattern was found for the majority of stand variables, soil microbial properties, and available macronutrients (N, P, S and base cations). Macronutrients such as N, P and S availability had a fine scale cyclic spatial association with soil microbial properties, with an 8-10 m oscillation, which indicated belowground control on these nutrients. Spatial regression models also suggested a stronger microbial influence on the availability of these nutrients when compared to stand characteristics. However, stand characteristics exhibited significant control on base cations and micronutrient availability through the effect of forest floor depth and tree clustering. Although nutrient availability showed strong spatial relationships with belowground processes in the studied reclaimed site, similar relationships with aboveground properties appeared to be

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： Document Classification   Feature Selection   Particle Swarm Optimization (PSO)   Genetic Algorithm (GA)  

摘要： Text categorization and feature selection are two of the many text data mining problems. In text categorization, the document that contains a collection of text will be changed to the dataset format, the dataset that consists of features and class, words become features and categories of documents become class on this dataset. The number of features that too many can cause a decrease in performance of classifier because many of the features that are redundant and not optimal so that feature selection is required to select the optimal features. This paper proposed a feature selection strategy based on Particle Swarm Optimization (PSO) and Genetic Algorithm (GA) methods for Arabic Document Classification with Naive Bayes Multinomial (NBM). Particle Swarm Optimization (PSO) is adopted in the first phase with the aim to eliminate the insignificant features and prepared the reduce features to the next phase. In the second phase, the reduced features are optimized using the new evolutionary computation method, Genetic Algorithm (GA). These methods have greatly reduced the features and achieved higher classification compared with full features without features selection. From the experiment that has been done the obtained results of accuracy are NBM 85.31%, NBM-PSO 83.91% and NBM-PSO-GA 90.20%.

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。