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991.
Ann Q. Gates Patricia J. Teller Andrew Bernat Nelly Delgado Connie Kubo Della-Piana 《工程教育杂志》1999,88(4):409-414
The benefits of working in a research group are clear: students develop domain expertise, gain an understanding and appreciation of the research process and its practice, and acquire team, communication, problem-solving, and higher-level thinking skills. Students with this experience are better equipped to make informed judgements about technical matters and to communicate and work in teams to solve complex problems. Clearly, this type of research experience must be made available to a broader population. This paper discusses how the Systems and Software Engineering Affinity Research Group model provides a socialization mechanism and infrastructure that supports the development and management of large research groups that engage undergraduate and graduate students, who have a wide range of skill levels and experiences, in research and projects. This non-hierarchical model, which is based on the cooperative paradigm, integrates students into small research groups and an encompassing large research group, and uses structured activities to develop their research, technical, communication, and group skills. 相似文献
992.
Dr. Rob Hoen Dr. Eva Maria Novoa Alba López Noelia Camacho Dr. Laia Cubells Pedro Vieira Prof. Manuel Santos Patricia Marin‐Garcia Prof. Jose Maria Bautista Prof. Alfred Cortés Prof. Lluís Ribas de Pouplana Dr. Miriam Royo 《Chembiochem : a European journal of chemical biology》2013,14(4):499-509
The resistance of malaria parasites to available drugs continues to grow, and this makes the need for new antimalarial therapies pressing. Aminoacyl‐tRNA synthetases (ARSs) are essential enzymes and well‐established antibacterial targets and so constitute a promising set of targets for the development of new antimalarials. Despite their potential as drug targets, apicoplastic ARSs remain unexplored. We have characterized the lysylation system of Plasmodium falciparum, and designed, synthesized, and tested a set of inhibitors based on the structure of the natural substrate intermediate: lysyl‐adenylate. Here we demonstrate that selective inhibition of apicoplastic ARSs is feasible and describe new compounds that that specifically inhibit Plasmodium apicoplastic lysyl‐tRNA synthetase and show antimalarial activities in the micromolar range. 相似文献
993.
Lee Bosher Andrew Dainty Patricia Carrillo Jacqueline Glass And Andrew Price 《Building Research & Information》2013,41(2):163-177
Although most disasters are not entirely unexpected and therefore can, to varying degrees, be mitigated for, the UK construction sector does not play a sufficiently integrated role in disaster risk management. Research is reported on the development of a knowledge database and decision support framework to enable more effective disaster risk-management strategies from a construction perspective. A survey of UK professionals involved with disaster risk-management activities (i.e. emergency planning, constructing, urban planning, insurance) indicates that knowledge and awareness of integrated approaches is poor, and the construction sector as a key stakeholder and potential resource is not being used sufficiently. Key recommendations to improve the construction sector in the process are as follows: construction-related stakeholders need to become more involved in groups such as Local Resilience Teams and Forums; risk and hazard awareness training needs to be integrated systematically into the professional training of architects, planners, engineers, developers, etc.; and the construction sector should embrace and pre-empt regulatory changes regarding resilient construction requirements. Bien que la plupart des catastrophes ne soient pas complètement inattendues et que, dans des proportions variables, elles puissent par conséquent être atténuées, l'industrie britannique du bâtiment ne s'implique pas suffisamment dans la gestion des risques de catastrophes. Il est rendu compte de recherches sur le développement d'une base de connaissances et d'un cadre de soutien à la prise de décision afin de rendre des stratégies de gestion des risques de catastrophes plus efficaces du point de vue de l'industrie du bâtiment. Une enquête auprès des professionnels britanniques impliqués dans les activités de gestion des risques de catastrophes (à savoir, planification des mesures d'urgence, construction, aménagement urbain, assurances) indique que le niveau de connaissances et de sensibilisation en matière d'approches intégrées est faible, et que le secteur du bâtiment en tant que partie prenante essentielle et ressource potentielle n'est pas suffisamment utilisé. Les principales recommandations pour améliorer le secteur du bâtiment sont les suivantes: il faut que les parties prenantes liées à l'industrie du bâtiment soient plus impliquées dans des groupes tels que les Equipes et les Forums Locaux de Résistance (Local Resilience Teams and Forums); il est nécessaire que les formations de sensibilisation aux risques et aux dangers soient systématiquement intégrées dans la formation professionnelle des architectes, des urbanistes, des ingénieurs, des promoteurs, etc., et le secteur du bâtiment devrait adopter facilement et anticiper les changements de réglementation relatifs aux obligations de résistance des constructions. Mots clés: secteur du bâtiment, atténuation des catastrophes, plans en prévision des catastrophes, gestion des risques de catastrophes, inondations, risques naturels, résistance, Royaume-Uni 相似文献
994.
Julio Bastos-Arrieta Maria Mu?oz Patricia Ruiz Dmitri N Muraviev 《Nanoscale research letters》2013,8(1):255
This paper reports the results of intermatrix synthesis (IMS) of silver metal nanoparticles (Ag-MNPs) in Purolite C100E sulfonic ion exchange polymer of the gel-type structure. It has been shown that the surface morphology of the initial MNP-free polymer is absolutely smooth, but it dramatically changes after the kinetic loading of Ag on the polymer and then IMS of Ag-MNPs. These morphological changes can be explained by the interaction of Ag-NPs with the polymer chains, leading to a sort of additional cross-linking of the polymer. As a result, the modification of the gel-type matrix with Ag-MNPs leads to the increase of the matrix cross-linking, which results in the increase of its surface area and the appearance of nanoporosity in the polymer gel. Ag-MNPs are located near the polymer surface and do not form any visible agglomerations. All these features of the nanocomposites obtained are important for their practical applications in catalysis, sensor applications, and bactericide water treatment. 相似文献
995.
996.
Patricia C. Rivas Jorge A. Martínez María C. Caracoche Agustín M. Rodríguez Alberto R. López García Robert S. Pavlik Jr. Lisa C. Klein 《Journal of the American Ceramic Society》1998,81(1):200-204
The evolution of the phase content in zirconia powders that have been prepared by sol—;gel acid hydrolysis has been investigated using the perturbed-angular-correlation (PAC) technique and X-ray diffractometry. As a consequence of performing annealing treatments at increasing temperatures between room temperature and 1000°C, the amorphous starting material transforms to the tetragonal form and then to the monoclinic form. The metastable tetragonal phase exhibits two hyperfine components, one of which describes very defective zirconium surroundings. The evolution of PAC relative fractions is in agreement with the diffraction results. The durability of the samples in sodium hydroxide seems to increase as the relative amount of the most-defective zirconium surroundings of the tetragonal form increases. 相似文献
997.
998.
Wissler Roselle L.; Kuehn Patricia F.; Saks Michael J. 《Canadian Metallurgical Quarterly》2000,6(3):712
The authors consider instructions that courts do or could give to jurors to guide them in making awards for general damages in civil litigation. The authors review the nature and content of current instructions about the factors that should (or should not) affect jurors' awards, as well as the limited body of empirical research on the impact of these instructions. The most noteworthy feature of current instructions regarding damages is the lack of guidance they provide. The consequence appears to be awards that have considerable variability and that are influenced by improper considerations. The authors also discuss research on the effectiveness of alternative forms of jury instructions and trial procedures in preventing or reducing these problems. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
999.
Tasha M. Santiago-Rodríguez Joel González Patricia Marcos Manuela Cadete Ricardo Santos Gary A. Toranzos 《Water research》2010,44(16):4716-4725
Enterophages are a novel group of phages that specifically infect Enterococcus faecalis and have been recently isolated from environmental water samples. Although enterophages have not been conclusively linked to human fecal pollution, we are currently characterizing enterophages to propose them as viral indicators and possible surrogates of enteric viruses in recreational waters. Little is known about the morphological or genetic diversity which will have an impact on their potential as markers of human fecal contamination. In the present study we are determining if enterophages can be grouped by their ability to replicate at different temperatures, and if different groups are present in the feces of different animals. As one of the main objectives is to determine if these phages can be used as indicators of the presence of enteric viruses, the survival rate under different conditions was also determined as was their prevalence in sewage and a large watershed. Coliphages were used as a means of comparison in the prevalence and survival studies. Results indicated that the isolates are mainly DNA viruses. Their morphology as well as their ability to form viral plaques at different temperatures indicates that several groups of enterophages are present in the environment. Coliphage and enterophage concentrations throughout the watershed were lower than those of thermotolerant coliforms and enterococci. Enterophage concentrations were lower than coliphages at all sampling points. Enterophages showed diverse inactivation rates and T90 values across different incubation temperatures in both fresh and marine waters and sand. Further molecular characterization of enterophages may allow us to develop probes for the real-time detection of these alternative indicators of human fecal pollution. 相似文献
1000.
Patricia Alvarez-Sieiro Hendrik R. Sikkema Bert Poolman 《International journal of molecular sciences》2021,22(11)
Many proteins have a multimeric structure and are composed of two or more identical subunits. While this can be advantageous for the host organism, it can be a challenge when targeting specific residues in biochemical analyses. In vitro splitting and re-dimerization to circumvent this problem is a tedious process that requires stable proteins. We present an in vivo approach to transform homodimeric proteins into apparent heterodimers, which then can be purified using two-step affinity-tag purification. This opens the door to both practical applications such as smFRET to probe the conformational dynamics of homooligomeric proteins and fundamental research into the mechanism of protein multimerization, which is largely unexplored for membrane proteins. We show that expression conditions are key for the formation of heterodimers and that the order of the differential purification and reconstitution of the protein into nanodiscs is important for a functional ABC-transporter complex. 相似文献