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51.
Martins Silvia S.; Mazzotti Guido; Chilcoat Howard D. 《Canadian Metallurgical Quarterly》2005,13(3):244
This study aims to estimate changes in the prevalence of ecstasy use over time, analyze the overlap of ecstasy use and other drug use, and compare other drug use in ecstasy versus marijuana users. The authors hypothesized that ecstasy users early in the "epidemic" would be polydrug users and that associations between ecstasy and other drug use would diminish as the prevalence of ecstasy use increased. Data were drawn from public use data files from the 1995, 1997, 1999, and 2001 National Household Survey on Drug Abuse. Ecstasy use increased in the U.S. population and the prevalence was greater in younger age groups. Ecstasy users were likely to use a variety of other drugs; however, association of ecstasy use with other drug use was strongest early in the "epidemic," diminishing as the number of new users increased. Later, more drug-naive adolescents and young adults began experimenting with ecstasy. These results can orient prevention strategies that target ecstasy users. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
52.
In most molten metal processing operations, the acts of melting, transporting and alloying the metal in preparation for casting into desired shapes introduces undesirable non‐metallic inclusions to the melt. Molten metals are highly reactive and tend to interact with gases and refractories during processing steps; undesirable phases are absorbed either as liquid or solid. Such examples of inclusion introduction are molten aluminum reacting with oxygen in air to form solid aluminum oxide, or molten cast iron reacting with oxygen in air to form liquid slag phases. 相似文献
53.
ROGUE is an architecture built on a real robot which provides algorithms for the integration of high-level planning, low-level robotic execution, and learning. ROGUE addresses successfully several of the challenges of a dynamic office gopher environment. This article presents the techniques for the integration of planning and execution.ROGUE uses and extends a classical planning algorithm to create plans for multiple interacting goals introduced by asynchronous user requests. ROGUE translates the planner';s actions to robot execution actions and monitors real world execution. ROGUE is currently implemented using the PRODIGY4.0 planner and the Xavier robot. This article describes how plans are created for multiple asynchronous goals, and how task priority and compatibility information are used to achieve appropriate efficient execution. We describe how ROGUE communicates with the planner and the robot to interleave planning with execution so that the planner can replan for failed actions, identify the actual outcome of an action with multiple possible outcomes, and take opportunities from changes in the environment.ROGUE represents a successful integration of a classical artificial intelligence planner with a real mobile robot. 相似文献
54.
Diana Tomás Joana Rodrigues Ana Varela Maria Manuela Veloso Wanda Viegas Manuela Silva 《International journal of molecular sciences》2016,17(2)
Genomic diversity of Portuguese accessions of Avena species—diploid A. strigosa and hexaploids A. sativa and A. sterilis—was evaluated through molecular and cytological analysis of 45S rDNA, and other repetitive sequences previously studied in cereal species—rye subtelomeric sequence (pSc200) and cereal centromeric sequence (CCS1). Additionally, retrotransposons and microsatellites targeting methodologies—IRAP (inter-retrotransposon amplified polymorphism) and REMAP (retrotransposon-microsatellite amplified polymorphism)—were performed. A very high homology was detected for ribosomal internal transcribed sequences (ITS1 and ITS2) between the species analyzed, although nucleolar organizing regions (NOR) fluorescent in situ hybridization (FISH) analysis revealed distinct number of Nor loci between diploid and hexaploid species. Moreover, morphological diversity, evidenced by FISH signals with different sizes, was observed between distinct accessions within each species. pSc200 sequences were for the first time isolated from Avena species but proven to be highly similar in all genotypes analyzed. The use of primers designed for CCS1 unraveled a sequence homologous to the Ty3/gypsy retrotransposon Cereba, that was mapped to centromeric regions of diploid and hexaploid species, being however restricted to the more related A and D haplomes. Retrotransposon-based methodologies disclosed species- and accessions-specific bands essential for the accurate discrimination of all genotypes studied. Centromeric, IRAP and REMAP profiles therefore allowed accurate assessment of inter and intraspecific variability, demonstrating the potential of these molecular markers on future oat breeding programs. 相似文献
55.
Front Cover: Photoactivatable Mussel‐Based Underwater Adhesive Proteins by an Expanded Genetic Code (ChemBioChem 18/2017) 下载免费PDF全文
Dr. Matthias Hauf Dr. Florian Richter Tobias Schneider Thomas Faidt Dr. Berta M. Martins Dr. Tobias Baumann Dr. Patrick Durkin Prof. Dr. Holger Dobbek Prof. Dr. Karin Jacobs Prof. Dr. Andreas Möglich Prof. Dr. Nediljko Budisa 《Chembiochem : a European journal of chemical biology》2017,18(18):1771-1771
56.
Fabiane Bach Cristiane Vieira Helm Marcelo Barba Bellettini Giselle Maria Maciel Charles Windson Isidoro Haminiuk 《International Journal of Food Science & Technology》2017,52(11):2382-2392
The main chemical and biochemical constituents of nine edible mushrooms were evaluated in this study. An enzymatic method was used to determine the α‐ and β‐glucan contents, and the amino acid (AA) profiles were evaluated by RP‐HPLC‐DAD. The recommended dietary allowance (RDA) of the nutrients was evaluated. Finally, principal component analysis (PCA) was used to group the mushrooms according to their AA, glucans and chemical composition. All mushrooms evaluated can be considered as a potential and alternative source of dietary fibre (24.4–46.62%) and protein (16.47–36.96%) in a diet, with low contents of fat (1.40–2.08%). Phosphorus, potassium, iron, copper and zinc were the main minerals found in the mushrooms, whereas sodium concentration was negligible. All essential AA were detected in the mushrooms, with Pleurotus ostreatus (black oyster) representing the main source of essential amino acids among the samples. The contents of β‐glucan ranged from 1.58 to 16.91 mg g?1 of dry matter among the mushrooms and Pleurotus eryngii presented the highest amount of this component. Pleurotus ostreatus (black oyster) and P. eryngii were also grouped together due to similarities in their phosphorous and arginine contents. Among the main results, it can highlight the high concentration of dietary fibre and essential amino acids of the edible mushrooms. 相似文献
57.
For stationary sequences, under general dependence restrictions, any limiting point process for time normalized upcrossings of high levels is a compound Poisson process, i.e., there is a clustering of high upcrossings, where the underlying Poisson points represent cluster positions and the multiplicities correspond to cluster sizes. For such classes of stationary sequences, there exists the upcrossings index η, 0≤η≤1, which is directly related to the extremal index θ, 0≤θ≤1, for suitable high levels. In this paper, we consider the problem of estimating the upcrossings index η for a class of stationary sequences satisfying a mild oscillation restriction. For the proposed estimator, properties such as consistency and asymptotic normality are studied. Finally, the performance of the estimator is assessed through simulation studies for autoregressive processes and case studies in the fields of environment and finance. Comparisons with other estimators derived from well known estimators of the extremal index are also presented. 相似文献
58.
Valesca Cristiane Benelli Francisco Clarissa Hamaio Okino-Delgado Mirella R. Zanutto Elgui Célio Junior da Costa Fernandes Roselaine Facanali Rodrigo Augusto da Silva Willian Fernando Zambuzzi Márcia Ortiz Mayo Marques Luciana Francisco Fleuri 《International Journal of Food Science & Technology》2019,54(4):1089-1099
The aim of this study was to show that abundant and inexpensive plant oils can be biotransformed to increase biological activity (antioxidant, antimicrobial and cytotoxicity) through hydrolysis reaction catalysed by lipases. We tested homemade and commercial lipases through the biotransformation of nine different plant oils in forty different combinations. First, the chemical composition of the samples was investigated. Thereafter, biological tests were conducted to assess the antioxidant and antimicrobial activity of the sampled biotransformation products, as well as analyzed their influence on the viability of healthy and cancer cells. Summarising, sunflower, corn and olive oils modified by orange waste-obtained lipases presented the most promising results, reaching up to 90% of antioxidant activity increase and significant growth inhibition of bacteria colonies belonging to genera Escherichia, Listeria, Staphylococcus, Pseudomonas and Salmonella. In addition, those compounds affected human oral squamous carcinoma cells. The bioconversion of plant oils through lipases improves their biological properties and might be an option for biotechnological application. 相似文献
59.
Alberto Abad Anna Pompili Angela Costa Isabel Trancoso José Fonseca Gabriela Leal Luisa Farrajota Isabel P. Martins 《Computer Speech and Language》2013,27(6):1235-1248
One of the most common effects among aphasia patients is the difficulty to recall names or words. Typically, word retrieval problems can be treated through word naming therapeutic exercises. In fact, the frequency and the intensity of speech therapy are key factors in the recovery of lost communication functionalities. In this sense, speech and language technology can have a relevant contribution in the development of automatic therapy methods. In this work, we present an on-line system designed to behave as a virtual therapist incorporating automatic speech recognition technology that permits aphasia patients to perform word naming training exercises. We focus on the study of the automatic word naming detector module and on its utility for both global evaluation and treatment. For that purpose, a database consisting of word naming therapy sessions of aphasic Portuguese native speakers has been collected. In spite of the different patient characteristics and speech quality conditions of the collected data, encouraging results have been obtained thanks to a calibration method that makes use of the patients’ word naming ability to automatically adapt to the patients’ speech particularities. 相似文献
60.