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121.
Feng Xin; Keenan Kate; Hipwell Alison E.; Henneberger Angela K.; Rischall Michal S.; Butch Jen; Coyne Claire; Boeldt Debbie; Hinze Amanda K.; Babinski Dara E. 《Canadian Metallurgical Quarterly》2009,45(3):798
Identifying childhood precursors for depression has been challenging and yet important for understanding the rapid increase in the rate of depression among adolescent girls. This study examined the prospective relations of preadolescent girls’ emotion regulation and parenting style with depressive symptoms. Participants were 225 children and their biological mothers recruited from a larger longitudinal community study. Girls’ observed positive and negative emotion during a conflict resolution task with mothers, their ability to regulate sadness and anger, and their perception of parental acceptance and psychological control were assessed at age 9. Depressive symptoms were assessed by self-report at ages 9 and 10. The results indicated interactions between child emotion characteristics and parenting in predicting later depression. Specifically, low levels of positive emotion expression predicted higher levels of depressive symptoms in the context of moderate to high parental psychological control. Low levels of sadness regulation were predictive of high levels of depressive symptoms in the context of low to moderate parental acceptance. Findings from this study support the hypothesis that the prospective association between vulnerabilities in emotion regulation and depression are moderated by the caregiving environment. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
122.
Kuo-Yi Yen Kuang-Pi Liu Jyh-Rong Gong Kuen-Yau Tsai Dong-Yuan Lyu Tai-Yuan Lin Guo-Yu Ni Far-Wen Jih 《Journal of Materials Science: Materials in Electronics》2009,20(12):1255-1259
Zinc oxide (ZnO) films were grown on (11-20) sapphire substrates at 600 °C by atomic layer deposition (ALD) using diethylzinc (DEZn) and nitrous oxide (N2O). A ZnO buffer layer was deposited at low temperature (LT) prior to the growth of a bulk ZnO film for a typical growth run. In some cases, buffer-layer annealing or post-annealing treatments were employed to optimize ZnO growth. Based on the experimental results of X-ray diffractometry (XRD) and transmission electron microscopy (TEM), all the as-grown ZnO films were found to show c-axis preferred orientation with co-existence of <1-100>ZnO∥<1-100>sapphire and <11-20>ZnO∥<1-100>sapphire relationships in the (0001)ZnO/(11-20)sapphire hetero-interface. Typical room temperature (RT) photoluminescence (PL) spectrum of the as-grown ZnO film shows only near band edge (NBE) emissions without defect luminescence. ZnO films with improved quality were achieved by post-annealing or buffer-layer annealing treatments. In particular, buffer-layer annealing was found to improve the crystalline and optical properties of a ZnO film substantially. 相似文献
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124.
挖掘用户属性对用户建模、用户检索和个性化服务等具有十分重要的意义.已有的相关研究工作都是单独挖掘各种属性,而且忽略了各属性之间的相关关系.提出一种基于超图学习的用户属性推断的方法.在超图中,顶点表示社会媒体中的用户,超边表示用户产生的内容相似性与属性之间的关系.在建好的超图模型上,把用户属性挖掘形式化成一个正则化的标签相似传播问题,可以有效推断得到用户的各种属性.利用从Google+上收集的标记过全部属性的数据集进行了大量的实验,其结果表明了该方法在用户属性挖掘中的有效性. 相似文献
125.
摘要:【目的】为辨别出口商品和国内市场中谎报香菇成分、以次从好的菌菇产品,准确核定菌菇产品的价格,打击出口骗税等不法行为,特应急研究开发本方法。【方法】选取香菇基因组单拷贝核基因Hydrophobin Protein基因,设计香菇种属特异性引物,扩增107 bp的片段,用于荧光PCR定量检测。分别以3种香菇作为阳性对照和14种非香菇菌种、植物产品作为阴性对照,测试实时荧光PCR引物和探针的特异性。以香菇标准DNA进行8个浓度梯度稀释,测试本定量方法绝对定量限。制备12个梯度含量的香菇DNA样品,测试香菇相对含量的标准曲线。【结果】结果表明本研究建立的香菇荧光PCR定量检测方法对香菇物种的特异性好,与其他食物物种无交叉结果,荧光PCR扩增效率为0.90,绝对定量限LOQ为0.01 ng和含量检测LOQ为0.05%。【结论】本方法重复性和实用性好,可以满足食品和调味料中香菇含量定性定量检测要求。 相似文献
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127.
Haixia Wu Changhua Liu Jianguang Chen Yun Chen Debbie P. Anderson Peter R. Chang 《应用聚合物科学杂志》2010,118(5):3082-3088
In this article, a series of oxidized pea starch/chitosan (OPS/CS) blend films were prepared by a casting and solvent evaporation method. The structure, thermal behavior, and mechanical properties of the films were investigated by means of Fourier transform infrared spectroscopy, wide‐angle X‐ray diffraction, scanning electron microscopy, thermogravimetric analysis, and tensile testing. The results suggested that, in addition to hydrogen bonding, the interactions between OPS and CS molecules were enhanced by the formation of electrostatic interaction between the negatively charged carboxyl groups on OPS and the positively charged amino groups on CS. Compared with the pea starch/chitosan (PS/CS) blend films, OPS/CS blend films exhibited significantly higher tensile strength with significantly lower elongation at break. Moreover, incorporation of CS into the OPS matrix also led to a decrease in moisture uptake by the composite film. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 相似文献
128.
Yajuan Yang Changhua Liu Peter R. Chang Yun Chen Debbie P. Anderson Mark Stumborg 《应用聚合物科学杂志》2010,115(2):1089-1097
Two series of composites, i.e., polyvinyl alcohol (PVA)/oxidized starch (OST)/exfoliated α‐zirconium phosphate (POST‐ZrPn) and PVA/starch (ST)/exfoliated α‐zirconium phosphate (PST‐ZrPn), were fabricated using a casting and solvent evaporation method. The composites were characterized by Fourier transform infrared spectroscopy (FT‐IR), thermal gravimetric analysis (TGA), differential scanning calorimetry (DSC), wide‐angle X‐ray diffraction (XRD), scanning electron microscopy (SEM), tensile testing, and moisture uptake. Compared with PST‐ZrPn, POST‐ZrPn films with the same component ratio showed higher tensile strength (σb), lower elongation at break (εb) and improved water resistance. Additionally, in the POST‐ZrPn series, σb and εb increased with an increase in α‐zirconium phosphate (α‐ZrP) loading; however, higher α‐ZrP loads resulted in the aggregation of α‐ZrP particles. Compared with POST‐ZrP0, the values for σb, εb, and water resistance of POST‐ZrP3, containing 1.5 wt % α‐ZrP, were increased by 128.8%, 51.4%, and 30.2%, respectively. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 相似文献
129.
Assessing the immunomodulatory potential of high‐molecular‐weight extracts from mushrooms; an assay based on THP‐1 macrophages
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130.
Shen L Reiner EJ MacPherson KA Kolic TM Helm PA Richman LA Marvin CH Burniston DA Hill B Brindle ID McCrindle R Chittim BG 《Environmental science & technology》2011,45(2):693-699
A chlorinated compound (Chlordene Plus, CP), structurally related to Dechloranes (Dec) 602, 603, 604, and Dechlorane Plus (DP), was identified, and concentrations and spatial trends of Dec 602, 603, 604, CP, and DP in tributary sediments of the Laurentian Great Lakes are reported. The dechloranes were widely detected with their concentrations varying considerably across the Great Lakes basin. Spatial trends of Dec 602, 604, and DP in Canadian tributary sediments were similar to that of BDE 209, which suggested these flame retardant chemicals in tributaries were associated with industrial and urban areas. The highest concentrations of Dec 602, 604, and DP observed in tributaries of the Niagara River confirmed that past or ongoing manufacturing of these compounds at plants along the river were important sources to Lake Ontario. Dec 603 was detected in technical products of aldrin and dieldrin, and its spatial trend was consistent with historic pesticide usage. Similarly, CP was detected in technical products of chlordene and chlordane, and it was found in higher concentrations in sediments near urban areas, possibly related to past chlordane use in home termite control. 相似文献