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51.
Exp I investigated the position that mirror-image confusions reflect an inability to attend to low-salient cues. 84 3–5 yr olds were given 3 problems: mirror-image matching, shape-detail matching, and consistent left–right ordering on a picture-naming task. With nonlearners, performance was reassessed following explicit instructions. This rendered Ss divisible into levels: spontaneous, instructed learners, and nonlearners. As predicted, most 3-yr-olds fell into identical categories across all low-salient problems, either instructed learners or nonlearners. The 4–5 yr olds were spontaneous or instructed learners but did not exhibit concordance across all problems. It is suggested that for these Ss, level differences reflected differences between nonreaders already attending to reading cues and those not yet attending. Exp II, with the 4–5 yr olds from Exp I, identified the nonreaders, who were given a letter-series and letter-writing task. Significant-levels agreement occurred among the prereading tasks involving attention to individual shape details. The ordering problem showed level concordance only with tasks involving left–right scanning. (21 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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The activation of latent transforming growth factor beta (L-TGFbeta) is essential for the action of TGFbeta, which, in turn, is involved in the regulation of expression of some progesterone-responsive genes. One mechanism by which TGFbeta is activated involves thrombospondin (TSP), a protein that binds extracellular proteins. Immunoreactive TSP (irTSP) protein and TSP-1 mRNA in myometrial tissues of ovulatory and pregnant women were localized by immunohistochemistry and in situ hybridization. IrTSP and TSP-1 mRNA were randomly distributed in myometrial smooth muscle cells of some, but not all, tissues of pregnant women at term before labor; but in some areas of most of these tissues, irTSP was intense and commonly localized extracellularly. Intense irTSP and TSP-1 mRNA in myocytes were more common in myometrium during labor. In myometrium from ovulatory women (n = 26), irTSP was localized primarily in vascular smooth muscle cells and was detected occasionally in scattered myocytes. Little TSP-1 mRNA was demonstrable by in situ hybridization in vessels or myocytes of myometrial tissue from ovulatory women (n = 7). By Northern analysis of total RNA, TSP-1 mRNA was detected in myometrial tissue of pregnant women and in human myometrial smooth muscle cells in culture. The levels of TSP-1 mRNA in myometrial tissues of pregnant women during labor (n = 18) were greater than those in myometrium at > 37 wk gestation before labor began (n = 25, p < 0.001). The ratios of TSP-1 to glyceraldehyde 3-phosphate dehydrogenase mRNAs in 3 myometrial tissues during oxytocin-induced labor were not statistically different from those in myometrium during spontaneous labor but were greater than those in myometrium before labor (p < 0.05). The level of TSP-1 mRNA in confluent human myometrial cells in culture was relatively high, was increased by treatment with fetal bovine serum, and was decreased by treatment with platelet-derived growth factor or activators of adenylyl cyclase or protein kinase C. Myometrial cells in culture constitute a useful model for studying the regulation of TSP-1 gene expression in human myometrium. 相似文献
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Taft Casey T.; Murphy Christopher M.; King Daniel W.; Musser Peter H.; DeDeyn Judith M. 《Canadian Metallurgical Quarterly》2003,71(4):812
This study used multilevel modeling to examine process and treatment adherence factors as predictors of collateral partner reports of abuse following participation in a cognitive-behavioral group treatment program for partner violent men (N = 107). Therapist working alliance ratings predicted lower levels of physical and psychological abuse at the 6-month follow-up and were the strongest predictors of outcome. Homework compliance partially mediated associations between early alliance ratings and psychological abuse at follow-up. Greater group cohesion during treatment, assessed by client report, also predicted lower physical and psychological abuse at follow-up. The findings support the promotion of a collaborative therapeutic environment to induce change among partner violent men. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
55.
Casey M. Beth; Nuttall Ronald L.; Pezaris Elizabeth 《Canadian Metallurgical Quarterly》1997,33(4):669
This study was designed to investigate whether spatial skill, math anxiety, and math self-confidence functioned as mediators of a significant gender difference in the Mathematics Scholastic Aptitude Test (SAT-M) among the top third of a college-bound sample. Using path analytic techniques, the decomposition of the significant gender—SAT-M correlation into direct and indirect effects indicated that there were no direct effects of gender on SAT-M. Mental rotation and math self-confidence showed indirect effects, mediating the gender—SAT-M relationship; math anxiety did not. Of these indirect effects, 36% was mediated by math self-confidence; 64% by mental rotation. For both these variables, most of the mediational effects of the gender—SAT-M relationship did not occur by way of the causal pathway leading through geometry grades. Thus, the mediational effects cannot simply be attributed to the presence of geometry items on the SAT-M or to math self-confidence acquired during prior geometry coursework. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
56.
L. V. Levitin R. G. Bennett A. Casey B. Cowan J. Saunders D. Drung Th. Schurig J. M. Parpia B. Ilic N. Zhelev 《Journal of Low Temperature Physics》2014,175(5-6):667-680
We review recent experiments in which superfluid $^3$ He has been studied under highly controlled confinement in nanofluidic sample chambers. We discuss the experimental challenges and their resolution. These methods open the way to a systematic investigation of the superfluidity of $^3$ He films, and the surface and edge excitations of topological superfluids. 相似文献
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A Multifunctional Nanoplatform for Imaging,Radiotherapy, and the Prediction of Therapeutic Response 下载免费PDF全文
Casey McQuade Ajlan Al Zaki Yaanik Desai Michael Vido Timothy Sakhuja Zhiliang Cheng Robert J. Hickey Daniel Joh So‐Jung Park Gary Kao Jay F. Dorsey Andrew Tsourkas 《Small (Weinheim an der Bergstrasse, Germany)》2015,11(7):834-843
Gold nanoparticles have garnered interest as both radiosensitzers and computed tomography (CT) contrast agents. However, the extremely high concentrations of gold required to generate CT contrast is far beyond that needed for meaningful radiosensitization, which limits their use as combined therapeutic–diagnostic (theranostic) agents. To establish a theranostic nanoplatform with well‐aligned radiotherapeutic and diagnostic properties for better integration into standard radiation therapy practice, a gold‐ and superparamagnetic iron oxide nanoparticle (SPION)‐loaded micelle (GSM) is developed. Intravenous injection of GSMs into tumor‐bearing mice led to selective tumoral accumulation, enabling magnetic resonance (MR) imaging of tumor margins. Subsequent irradiation leads to a 90‐day survival of 71% in GSM‐treated mice, compared with 25% for irradiation‐only mice. Furthermore, measurements of the GSM‐enhanced MR contrast are highly predictive of tumor response. Therefore, GSMs may not only guide and enhance the efficacy of radiation therapy, but may allow patients to be managed more effectively. 相似文献
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Zitnick KK Shappell NW Hakk H DeSutter TM Khan E Casey FX 《Journal of hazardous materials》2011,186(2-3):1111-1117
17β-estradiol (E2), a natural estrogenic hormone, degrades within hours and bind strongly to soils and sediments; however, estrogens are frequently detected in the environment at concentrations that impact water quality. Colloidal (COC) and dissolved (DOC) organic carbon may enhance the persistence and mobility of E2. Soil batch experiments were used to identify the persistence and sorption of radiolabeled E2 dissolved in solutions of (i) COC/DOC derived from liquid swine manure and (ii) CaCl(2). Estradiol disappeared from the aqueous phase before 7 d in the CaCl(2) solution, yet persisted throughout the duration of the 14 d experiment in the liquid manure solution. There was also concomitant formation of estrone (E1; a metabolite of E2) as E2 dissipated in sterile batch experiments, which was attributed to abiotic oxidation. The liquid manure solution appeared to interact with the estrogen and/or oxidation reaction sites, reducing E2 degradation. Furthermore, the liquid manure solution reduced E2/E1 binding to the soil surface resulting in more E2/E1 in the aqueous layer compared to the CaCl(2) solution. Ultrafiltration results of liquid manure indicated that ~1/3 of E2 was associated with COC, which may be responsible for the reduced degradation and sorption of E2 in the liquid manure solution. 相似文献