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1.
Advances in online geospatial technologies (GST) have expanded access to K-12 classrooms which has implications for the support teachers require to effectively integrate GSTs to promote learning. Previous studies have shown the impact of GST-integrated lessons on student engagement, spatial thinking skills, and/or content knowledge; however, most of these studies have been small in scope and scale and frequently focus on the affordances of the technology, without addressing the context of the implementation and student characteristics for whom GST is most impactful. We attempt to address some of these gaps. Our program scaled an effective GST-focused professional learning and development program to a national audience through a facilitator development model. This paper explores the student characteristics and lesson factors that resulted in student interest in science and technology and careers in those fields. After teaching a Geospatial Inquiry lesson created during a teacher workshop, teachers (n = 82) submitted the lessons and surveys on the implementation of Geospatial Inquiry lessons. The implementation surveys and lessons were scored for alignment to the principles of high-quality Geospatial Inquiry. Students (n = 1924) completed a post-lesson retrospective survey and indicated the extent to which their perceptions and attitudes toward science and technology changed because of the lesson. Results indicate that teacher GST performance is associated with increases in student outcomes. Students with previous exposure to science activities were more likely to have increased interest and excitement in science and careers in science but decreased interest in technology careers. Students who had previous exposure to technology activities had increased interest and excitement in technology and careers in technology but decreased interest in science careers. Geospatial Inquiry lessons also had a significant impact on students who are traditionally underrepresented in STEM fields. After participating in the lessons, students who identify as female reported higher engagement and interest in science and higher interest in science careers. Students who identified as Black or Hispanic also reported higher interest and excitement in science and technology, and students who identified as Black reported marginally higher interest in science careers.  相似文献   
2.
目的:观察2型糖尿病(T2DM)模型大鼠,经8周游泳训练后,血脂代谢、血清氧化应激、血糖(FBG)、胰岛素敏感性(ISI)及肝脏组织二相酶活性变化,检测联合作用方式(游泳训练及联合补充α硫辛酸)对wistarT2DM大鼠血脂代谢及脂质过氧化水平的影响,并探讨其内在影响机制。方法:实验材料wistar大鼠60只,造模完成后随机分成4组,对照组(CON);α硫辛酸(LA);游泳运动组(SEX);α硫辛酸+游泳运动组(LA+SEX),每组15只。进行游泳训练共计8周,观察各组大鼠血脂代谢水平、FBG、ISI及肝脏组织二相酶活性变化。结果:经联合作用方式可极显著性降低wistar大鼠血清总胆固醇和甘油三酯水平,降低LDL-C含量和FFA水平,提高HDL-C;在降低FBG,提高ISI作用上存在叠加效应(P<0.01),对胰岛素水平无显著性影响;在改善血清氧化应激水平作用上(降低ROS和提高SOD),存在增强作用(P<0.01);对肝脏组织二相酶的影响,在对谷胱甘肽-S-转移酶(GST)和谷胱甘肽过氧化物酶(GPX)存在增强作用,对醌氧化还原酶1(NQO-1)则无此作用。结论:联合作用方式可以有效降低血清及肝脏脂质过氧化水平,纠正血脂代谢异常,提高ISI。其保护作用可能是通过降低机体氧化应激水平,维持机体血脂正常代谢水平,减少氧化应激而实现。提示,联合作用方式可以为治疗T2DM提供新思路。  相似文献   
3.
Accuracy and fastness of iris localization are very important in automatic iris recognition. A new fast iris localization algorithm based on improved generalized symmetry transform (GST) was proposed by utilizing iris symmetry. GST was improved in three aspects: 1 ) A new distance weight function is defined. The new weight function, which is effective in iris localization, utilized the characteristic of irises that the iris is a circular object and it has one inner boundary and one outer boundary. 2) Each calculation of the symmetry measurement of a pair of symmetry points was performed by taking one point of a pair as the starting point of the transformation. This is the most important reason for fast iris localization, due to which, repetitious computation was largely excluded. 3) A new phase weight function was proposed to adjust GST to locate circle target much better because the inner part of iris is darker than the outer part. The edge map of iris image was acquired and GST was only implemented on the edge point, which decreased computation without loss of accuracy. The modification of distance weight function and phase weight function leads to the accuracy of localization, and other ideass peed up the localization. Experiments show that the average speed of new algorithm is about 7.0-8.5 times as high as traditional ones including integro-differential operator and Hough transform method.  相似文献   
4.
研究用亲和融合谷胱甘肽 S 转移酶 (GST)的方法纯化重组人白细胞介素 6(IL 6)的发酵和纯化工艺 ,使用含有质粒pHZl818的E .coliJMl0 9在 2XYT培养基中进行发酵表达 ,IL 6表达为与谷胱甘肽 S 转移酶 (GST)融合的融合蛋白GST IL 6.融合蛋白存在可溶的活性蛋白和不可溶的包含体两种形式 ,此包含体无活性且无法复性 ,无法用亲和层析回收 ,通过实验优化摇床发酵的诱导温度和转速 ,以增加可溶融合蛋白的表达 .菌体超声破碎液后 ,上清液用作亲和柱层析 ,可将融合蛋白提纯至 80 00 ,每升发酵液可得 10mg融合蛋白 ,用凝血酶裂解处理 6h ,亲和标志物GST被特异性切除 ,裂解得到的IL 6用离子交换柱层析可纯化至 95 00 ,MTT法测得纯化的IL 6生物学活性为 1.0 2× 10 8IU/mg .  相似文献   
5.
Two common fish species, mosquitofish (Gambusia affinis) and topmouth gudgeon (Pseudorasobora para) were exposed to different concentrations of fenitrothion in static system for 96 h. Hepatic glutathione S-transferase activity was evaluated after 48 and 96 h pesticide exposure, and was also examined in fish pretreated with pepironyl butoxide and triphenyl phosphate and then exposed to fenitrothion. Results indicated presence of intense glutathione S-transferase activity in both species, mosquitofish exhibiting the higher activity. In both species the activity decreased as the concentration of fenitrothion increased, topmouth gudgeon being more susceptible than mosquitofish. In mosquitofish pretreated with pepironyl butoxide, glutathione S-transferase activity was increased (11.8%) compared with the control but in topmouth gudgeon it was decreased (21.6%) at the end of 96 h. Glutathione S-transferase activity was significantly reduced in both species pretreated with triphenyl phosphate at the end of 96 h exposure, topmouth gudgeon being highly susceptible. Ph. D. student, from Southern Ethiopia Health Bureau, Center for Health Research, P. O. Box 317, Awassa, F. R. Ethiopia.  相似文献   
6.
基于基因工程技术 ,用PCR法扩增出编码ICA6 9的cDNA片段 ,直接克隆到pSPORT 1质粒上 ,经DNA序列测定 ,插入到GST融合蛋白表达载体 pGEX 2T ,构成重组质粒 p2T ICA6 9,得到的表达产物GST ICA6 9融合蛋白用间接ELISA法检测其免疫原性 .测序结果表明 ,所获PCR产物已正确重组到PGEX 2T表达型质粒中 .重组质粒在原核细胞中表达的融合蛋白具有免疫原性 ,并能应用于Ⅰ型糖尿病病人血清中抗ICA6 9抗体的检测 .所获得的表达产物为重组ICA6 9融合抗原 ,有助于提高Ⅰ型糖尿病的预报率和确诊率 .  相似文献   
7.
近年来,有关GST与癌的易感性受到了人们广泛的关注。采用综述的方法,阐述GST基因多态性与肝癌、胃癌、肺癌易感性研究进展,及其在高原环境下与运动能力的相关性研究进展。结果显示:GST基因多态性与高原环境下人体运动能力相关,可将GST基因多态性作为评价人群适应高原低氧环境的指标。  相似文献   
8.
Erythrocyte antioxidant glutathione and malondialdehyde levels in erythrocytes and plasma glutathione S-transferase levels were estimated in patients with colorectal cancer and compared to controls. Further, the patients underwent four weeks of radiotherapy with adjuvant chemotherapy. The same parameters were estimated after four weeks of radiotherapy and compared with pretreatment levels. It was observed that there was a decrease in erythrocyte glutathione and malondialdehyde levels in patients with colorectal cancer compared to controls, but not in case of GST. However, after chemoradiotherapy, there were no statistically significant differences in all the parameters studied.  相似文献   
9.
INTRODUCTIONFenitrothion(0,0dimethyl0(3methyl4nitrophenol)phosphorothioate),theactiveingredientintheformulatedproductsumithion,isanorganophosphate(O-P)insecticideandusedinagricultureforcropprotectionandcontrolofvectorborndiseasesinvariouscountries(Selfetal.,19…  相似文献   
10.
谷胱甘肽S-转移酶(glutathione S-transferases ,GSTs)在昆虫代谢各种内源和外源性有害化合物的过程中起关键作用。重要水稻害虫稻纵卷叶螟(Cnaphalocrocis medinalis)的GST基因目前尚无研究。本实验克隆了一个稻纵卷叶螟delta家族GST基因的全长cDNA序列,命名为CmGSTd3(Genbank登录号KM433686)。CmGSTd3包含681 bp的开放阅读框,编码一个由226个氨基酸组成的蛋白。CmGSTd3蛋白是一个胞质GST ,与已知的昆虫delta家族GST 具有较高的同源性。在系统进化分析中,CmGSTd3与家蚕的delta家族GST聚在同一进化分支上。实时荧光定量PCR结果显示,CmGSTd3基因在稻纵卷叶螟幼虫阶段表达量最高,且主要表达于幼虫的中肠和脂肪体,由此推测其可能参与了体内异源毒物的代谢。本研究为探索CmGSTd3的生理功能奠定了前期基础。  相似文献   
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