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151.
83 individuals and organizations in 28 foreign countries using the USES General Aptitude Test Battery are listed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
152.
Fibril-forming collagen proteins of the types I, III, and V were extracted from fetal calf skin, purified by differential salt precipitation, and analyzed by infrared matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (IR-MALDI-TOF-MS). Glycerol was used as liquid IR-MALDI matrix. Noncovalently bound triple helices of the types I and V were detected from the NaCl precipitate. After heating at 43 degrees C for 10 min, resulting in the dissociation of the triple helix, the single alpha-chain subunits were detected. For type I, mass spectra acquired from molecular sieve chromatography fractions revealed the presence of further substructures of dimeric type and of supramolecular complexes up to the tetramer. Triple helices of type III, stabilized by covalent disulfide bonds, were detected from the total protein precipitate also after heat treatment. For type III, even hexamer and nonamer structures with molecular weights close to 600 and 900 kDa were recorded. For comparison, ultraviolet (UV-)MALDI-MS measurements with 2,5-dihydroxybenzoic acid as matrix were carried out with some of the samples. Here, only the single alpha-chains were detected with significantly reduced sensitivity. 相似文献
153.
The Vehicle Routing Problem with Time windows (VRPTW) is an extension of the capacity constrained Vehicle Routing Problem
(VRP). The VRPTW is NP-Complete and instances with 100 customers or more are very hard to solve optimally. We represent the
VRPTW as a multi-objective problem and present a genetic algorithm solution using the Pareto ranking technique. We use a direct
interpretation of the VRPTW as a multi-objective problem, in which the two objective dimensions are number of vehicles and
total cost (distance). An advantage of this approach is that it is unnecessary to derive weights for a weighted sum scoring
formula. This prevents the introduction of solution bias towards either of the problem dimensions. We argue that the VRPTW
is most naturally viewed as a multi-objective problem, in which both vehicles and cost are of equal value, depending on the
needs of the user. A result of our research is that the multi-objective optimization genetic algorithm returns a set of solutions
that fairly consider both of these dimensions. Our approach is quite effective, as it provides solutions competitive with
the best known in the literature, as well as new solutions that are not biased toward the number of vehicles. A set of well-known
benchmark data are used to compare the effectiveness of the proposed method for solving the VRPTW. 相似文献
154.
Beatrice Isaacs 《Canadian Metallurgical Quarterly》2001,127(2):85-91
Despite intensive recruiting efforts by engineering schools and professional societies, the number of women employed as engineers in the United States has never reached 10%. This failure is generally attributed to the fact that girls tend to shy away from math and science in high school. Recruiting efforts are therefore directed toward encouraging girls to study math and science, but these efforts are focused on the wrong problem. Some reasons for the scarcity of female engineers are: the general public's lack of understanding of what engineers do; a misguided emphasis on math and science, rather than problem solving, that makes girls think that engineering is not for them; and the poor image of the engineering profession. Efforts to recruit bright young people, male and female, into the engineering profession will be fruitful when they are focused on engineering, rather than its tools. This can be done by educating the public about what engineering really is and by making schoolchildren aware that being an engineer goes way beyond “doing math and science.” 相似文献
155.
Stefano Salciccia Anna Laura Capriotti Aldo Lagan Stefano Fais Mariantonia Logozzi Ettore De Berardinis Gian Maria Busetto Giovanni Battista Di Pierro Gian Piero Ricciuti Francesco Del Giudice Alessandro Sciarra Peter R. Carroll Matthew R. Cooperberg Beatrice Sciarra Martina Maggi 《International journal of molecular sciences》2021,22(9)
Early detection of prostate cancer (PC) is largely carried out using assessment of prostate-specific antigen (PSA) level; yet it cannot reliably discriminate between benign pathologies and clinically significant forms of PC. To overcome the current limitations of PSA, new urinary and serum biomarkers have been developed in recent years. Although several biomarkers have been explored in various scenarios and patient settings, to date, specific guidelines with a high level of evidence on the use of these markers are lacking. Recent advances in metabolomic, genomics, and proteomics have made new potential biomarkers available. A number of studies focused on the characterization of the specific PC metabolic phenotype using different experimental approaches has been recently reported; yet, to date, research on metabolomic application for PC has focused on a small group of metabolites that have been known to be related to the prostate gland. Exosomes are extracellular vesicles that are secreted from all mammalian cells and virtually detected in all bio-fluids, thus allowing their use as tumor biomarkers. Thanks to a general improvement of the technical equipment to analyze exosomes, we are able to obtain reliable quantitative and qualitative information useful for clinical application. Although some pilot clinical investigations have proposed potential PC biomarkers, data are still preliminary and non-conclusive. 相似文献
156.
157.
正"……行动就是形式。"——凯勒·伊斯特林,《超国家机器一基础设施空间的力量》~([1][2])目前有一股来自当代设计知识领域的变质效应正在加速产生影响。它产生于一个重要的时间节点,即技术进步与设计师最终产品——无论是物件、设施、还是程序——为人们所接触到的容易程度相互交叠,正在让个体能够与他们的构成性规则及结构形成更为个人、更具感染力和更为日常可见的关系。信息作为对不断影响扩大的全球参与范式进行形态转换的终极标志,现在与数据、设备和空间紧密交 相似文献
158.
159.
Domenico Borello Gabriele Gagliardi Giorgia Aimola Valeria Ancona Paola Grenni Giuseppe Bagnuolo Gian Luigi Garbini Ludovica Rolando Anna Barra Caracciolo 《International Journal of Hydrogen Energy》2021,46(16):10131-10142
DDE (2,2-bis (p-chlorophenyl)-1,1-dichloroetylene) is a very persistent and bioaccumulative pesticide and its residues are continuously found in the environment. Among the green remediation strategies for soil recovery, terrestrial Microbial Fuel Cells (MFC) are arousing great interest in scientific community. MFCs transform energy stored in the chemical bonds of organic compounds into electrical energy thanks to exo-electrogen microorganisms naturally occurring in soil, which catalyse oxidation and reduction reactions in the area between two graphite electrodes. This work reports preliminary data on the use of MFCs for promoting soil decontamination from DDE. Several experimental conditions (e.g. addition of compost and open/closed circuit) were applied for assessing how to improve MFC performance in favouring DDE removal. MFCs promoted a significant DDE removal (39%) after 2 months, while at the same time any pesticide decrease was observed in the batch condition. Compost addition stimulated microbial activity and improved MFC performance for a longer time. 相似文献
160.
Conducting porous nanofibrous composite membranes of bacterial cellulose (BC) and polypyrrole (PPy) were prepared through in situ oxidative chemical polymerization of pyrrole (Py) on the surface of synthetized BC nanofibers by using FeCl3 as oxidant agent. The influence of polymerization conditions on electrical conductivity, morphological and thermal stability of the BC/PPy composites was investigated. The amount of PPy deposited on the BC nanofibers increased with increasing the monomer concentration and reaction time while the electrical resistivity of the composites decreased due to the formation of a continuous layer that coated the nanofiber surface. Fourier transform infrared (attenuated total reflectance mode) spectroscopy (FTIR-ATR) of the composites revealed strong interaction between PPy and BC, as characterized by a blue-shift of C–N band of PPy towards pure PPy with increasing Py concentration. BC/PPy composites showed higher thermal stability than BC membrane due to the protective effect of the conducting polymer coating. Scanning electron microscopy (SEM) analysis of the composites revealed that PPy consisted of particles of mean size of 35 nm that form a continuous coating that fully encapsulates the BC nanofibers. The material properties obtained by the method described in this work for the BC/PPy composites open interesting possibilities for novel applications of electrically conducting bio-based composites, particularly those that may exploit the biocompatible nature of the BC/PPy membranous composite. 相似文献