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31.
Cover Picture: Tetrahydroisoquinolinone‐Based Steroidomimetic and Chimeric Microtubule Disruptors (ChemMedChem 1/2014) 下载免费PDF全文
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Jouriles Ernest N.; Brown Alan S.; Rosenfield David; McDonald Renee; Croft Kathryn; Leahy Matthew M.; Walters Scott T. 《Canadian Metallurgical Quarterly》2010,24(4):592
This study evaluated methods of enhancing college students' retention of information provided to them in a computer-delivered personalized drinking feedback intervention and whether enhanced retention reduced alcohol consumption during the two-week period following the intervention. Participants were 98 college students who reported at least one heavy drinking episode in the past two weeks. After participating in an online, personalized drinking feedback intervention, students were randomly assigned to one of three experimental conditions: 1) typical, in which they were simply sent home, 2) reading, in which they were asked to spend the next 20 minutes re-reading the feedback, and 3) recall, in which they were asked to spend the next 20 minutes writing down as much of the information from the feedback as they could remember. Two weeks following the intervention, participants completed a recall test and provided information on their alcohol use during the previous two weeks. Results indicated that participants in the reading and recall conditions retained more of the feedback information than did participants in the typical condition. In addition, participants in the reading and recall conditions reported reduced alcohol consumption in the two-week period following the intervention, compared to those in the typical condition. Information retention partially mediated the effects of the reading and recall conditions on drinking outcomes. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
35.
A 1-year study was carried out to investigate the prevalence of Salmonella in two abattoir environments coded "A" and "B" in Gaborone, Botswana. The total number of environmental samples collected from abattoirs A and B was 250 and 300, respectively. The samples were taken from soils in the corrals, knife blades, saw blades, cattle-drinking water, cattle feces, and feed. Preenrichment, enrichment, and selective/differential media, which enabled the favorable growth of Salmonella, were used in the study. Salmonellae were present in all sampled environments. The most common serotypes found in the environment at abattoir A were E1, C1, C2, and B. Serotypes B, C1, C2, C3, and E1 were common in abattoir B. Antigenic characterization of the salmonellae isolates showed that Salmonella Anatum, Salmonella Azteca, Salmonella Saintpaul, Salmonella Cerro, and Salmonella Westhampton were predominant in abattoir A, whereas Salmonella Anatum, Salmonella Mbandaka, Salmonella Molade, Salmonella Reading, and Salmonella Oranienburg were dominant in abattoir B. Implementing hazard analysis critical control point principles in work procedures would definitely reduce the gross contamination taking place in abattoirs. 相似文献
36.
The mathematician-architect Christopher Alexander has devised a theory of objective architectural design. He believes that
all architectural forms can be described as interacting patterns, all possible relationships of which are governed by generative
rules. These form a ‘pattern language’ capable of generating forms appropriate for a given environmental context.
The complexity of interaction among these rules leads to difficulties in their representation by conventional methods. This
paper presents a Prolog-based expert system which implements Alexander's design methodology to produce perspective views of
partially and fully differentiated 3-dimensional architectural forms. 相似文献
37.
32 learning disabled and slowly developing readers were assigned to reading instruction programs on context cue use differing only in extent of pupil control over determination of errors. Results indicate no main effect for experimental condition. However, a significant interaction was found between pretreatment Locus of Attribution (Intellectual Achievement Responsibility Scale) and Experimental Condition. Ss high in internal control benefited more under a condition in which they were encouraged to determine the correctness of their responses. Conversely, Ss low in internality benefited more from a condition in which the teacher determined the correctness of their responses. The results suggest that individual differences in locus of attribution may be important determinants of the extent to which learning-disabled and slow readers benefit from different approaches to reading instruction. (23 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
38.
Morris Young Ernest Levine Harold Margolin 《Metallurgical and Materials Transactions B》1974,5(8):1891-1898
In Ti-6-2-4-6 alloys, beta transforms to orthorhombic martensite when quenched from a temperature of 1188 or above, X-ray
analysis showed that aging at 773 or 873 gradually reduces the degree of orthorhombicity until a hexagonal structure equivalent
to alpha, but having the morphological characteristics of the prior martensite, is produced. The orthorhombicity is reduced
by solute rejection to beta which forms as particles both homogeneously and heterogeneously within the martensitic structure.
The structure at maximum hardness is a fine distribution of Burger’s oriented beta particles in a matrix of martensite of
greatly reduced orthorhombicity. Overaging appears to occur as a result of coarsening of the homogeneous beta particles. It
is shown that aging at temperatures from 873 to 1083 K results in growth of one particular varient of the beta which is located
at the interface between twin related regions composing a martensite lath. This beta along with similarly oriented beta at
lath interfaces forms a continuous beta matrix by a gradual growth process. It is shown that this matrix has the identical
orientation and shape of the original beta grain prior to quenching. A mechanism is proposed to account for this “memory effect”. 相似文献
39.
Quantitative scanning electron microscope (SEM) studies of cement-stabilized waste specimens exposed to a leaching solution at constant pH in the range 4-7 have shown that the acid neutralization capacity (ANC) of the waste matrix is consumed at two consecutive leaching fronts. The first front is associated with the dissolution of portlandite (Ca(OH)2) and the partial reaction of calcium silicate hydrate (CSH) gel. The second front marks the dissolution of Ca-Al hydroxy sulfate minerals. The advancement of the first front is limited by the diffusion of OH- ions from the first front toward the leaching solution. The advancement of the second front, however, is controlled by the diffusion of H+ ions from the leaching solution toward the second front. Leaching of copper, zinc, and lead only occurs between the second front and the specimen surface. The leaching behavior of metals is modeled by considering that metals are leached from the waste matrix as a result of the advancement of the second front. The proposed model takes into account the leachable metal fraction in the waste matrix and the effect of metal remineralization on metal mobility. 相似文献
40.
Sjödin A McGahee EE Focant JF Jones RS Lapeza CR Zhang Y Patterson DG 《Analytical chemistry》2004,76(15):4508-4514
A semiautomated extraction and cleanup method has been developed to measure eight polybrominated diphenyl ethers (PBDEs), 2,2',4,4',5,5'-hexabromobiphenyl (BB-153), and 2,2',4,4',5,5'-hexachlorobiphenyl (CB-153). The method employs solid-phase dispersion on diatomaceous earth in a solid-phase extraction cartridge followed by automated addition of internal standards ((13)C-labeled). Extraction is then performed using an automated modular solid-phase extraction system. The extraction procedure includes drying the sample on diatomaceous earth by pressurized nitrogen and eluting target analytes and lipids with dichloromethane. Lipid content is determined gravimetrically. Lipid determinations performed using this method are compared with other standard methods and with a certified reference material. A relative standard deviation of 7.9% was obtained for 130 determinations of the lipid content in a breast milk quality control sample. Final analytical determination of target analytes was performed by gas chromatography-isotope dilution high-resolution mass spectrometry. Relative standard deviations for the measurements of target analytes for which a labeled internal standard was available were below 10% for analytes at concentrations above 1 ng/g of lipid. Mean recoveries of the (13)C-labeled internal standards ranged from 60 to 89% for the eight PBDE congeners; 74 and 113% were recovered for BB-153 and CB-153, respectively. 相似文献