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Arabidopsis FtsZ2-1 and FtsZ2-2 Are Functionally Redundant, But FtsZ-Based Plastid Division Is Not Essential for chloroplast Partitioning or Plant Growth and Development

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Molecular Plant 2009年第6期2卷 1211-1222页

作者： Aaron J. Schmitz Jonathan M. Glynn bradley J.S.c. Olson Kevin D. Stokes Katherine W. Osteryoung Department of Plant Biology 166 Plant Biology Bldg Michigan State University East Lansing MI 48824-1312 USA cell and Molecular Biology Program Michigan State University East Lansing MI 48824 USA Department of Energy-Plant Research Laboratory Michigan State University East Lansing MI 48824 USA Genetics Program Michigan State University East Lansing MI 48824 USA Biochemistry and Molecular Biology Program Michigan State University East Lansing MI 48824 USA Present address: The Salk Institute for Biological Studies Plant Molecular and Cellular Biology Laboratory La Jolla CA 92037 USA Present address: Mycobacteria and Brucella Section NVSL/APHIS/USDA 1920 Dayton Ave Ames IA 50010 USA

FtsZ1 and FtsZ2 are phylogenetically distinct families of FtsZ in plants that co-localize to mid-plastid rings and facilitate division of chloroplasts. In plants, altered levels of either FtsZ1 or FtsZ2 cause dose-dependent defects in chloroplast division; thus, studies on the functional relationship between FtsZgenes require careful manipulation of FtsZ levels in vivo. To define the functional relationship between the two FtsZ2 genes in Arabidopsis thaliana, FtsZ2-1 and FtsZ2-2, we expressed FtsZ2-1 in an ftsZ2-2 null mutant, and vice versa, and determined whether the chloroplast division defects were rescued in plants expressing different total levels of FtsZ2. Full rescue was observed when either the FtsZ2-1 or FtsZ2-2 level approximated total FtsZ2 levels in wild-type （WT）. Additionally, FtsZ2-2 interacts with ARc6, as shown previously for FtsZ2- 1. These data indicate that FtsZ2-1 and FtsZ2-2 are functionally redundant for chloroplast division in Arabidopsis. To rigorously validate the requirement of each FtsZ family for chloroplast division, we replaced FtsZ1 with FtsZ2 in vivo, and vice versa, while maintaining the FtsZ level in the transgenic plants equal to that of the total level in WT. chloroplast division defects were not rescued, demonstrating conclusively that FtsZ1 and FtsZ2 are non-redundant for maintenance of WT chloroplast numbers. Finally, we generated ftsZtriple null mutants and show that plants completely devoid of FtsZ protein are viable and fertile. As plastids are presumably essential organelles, these findings suggest that an FtsZ-independent mode of plastid partitioning may occur in higher plants.

关键词： chloroplast plastid division FtsZ ARc6 PDV1.

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Switching Schools Affects Student Achievement

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科技英语学习 2009年第8期 6-8页

作者： carol c.bradley 施小娟

【编者按】如果你正在考虑为孩子转学，请慎重。美国印第安那州圣母大学的研究表明，频频转学不但影响孩子的学习，造成学习成绩下降，而且可能使他们再也难以赶上其他学生，甚至对班上其他孩子的学习也可能产生负面的影响。基于这些考... 详细信息

【编者按】如果你正在考虑为孩子转学，请慎重。美国印第安那州圣母大学的研究表明，频频转学不但影响孩子的学习，造成学习成绩下降，而且可能使他们再也难以赶上其他学生，甚至对班上其他孩子的学习也可能产生负面的影响。基于这些考虑，教育人士应当采取措施来帮助降低学生的流动性，其中最重要的一点就是让孩子的父母意识到孩子频繁转学可能造成的巨大危害。

关键词：英语学习方法翻译方法译文

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Placental accommodations for transport and metabolism during intra-uterine crowding in pigs

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Journal of Animal Science and Biotechnology 2015年第2期6卷 163-176页

作者： Jeffrey L Vallet Anthony K Mc Neel Jeremy R Miles bradley A Freking U.S. Department of Agriculture Agricultural Research Service U.S. Meat Animal Research CenterState Spur 18D Clay Center NE 68933 USA

Litter size and birth weights are limited by uterine capacity, defined as the ability of the uterus to maintain the appropriate development of some number of conceptuses. Uterine capacity is the result of the combined effects of uterine, placental and embryo/fetal function. The number of living conceptuses that the uterus is capable of supporting is greater during early gestation compared to later gestation. Plots of log fetal weight versus log placental weight also indicate that fetal weights are less sensitive to reduced placental weight （and therefore reduced intrauterine space） in early gestation compared to late gestation. However, even in late gestation, mechanisms still exist that maintain fetal growth when the size of the placenta is reduced. One such mechanism is likely to be improved development of the folded placental-epithelial/maternal-epithelial bilayer. Fold depth, and therefore the maternal fetal interactive surface, increases as gestation advances and is greater in placenta from smal fetuses. On the fetal side of the placenta, the epithelial bilayer is embedded in stromal tissue. Glycosaminoglycans are major components of stroma, including hyaluronan and heparan sulfate. Hyaluronidases and heparanases are present within placental tissues, and likely play roles in modification of stromal components to facilitate fold development. Glycosaminoglycans are polymers of forms of glucose （glucosamine, glucuronic acid, iduronic acid） suggesting that glycosaminoglycan synthesis may compete with the glucose needs of the developing fetus. Pig conceptuses are fructogenic, such that a substantial portion of glucose transferred from mother to fetus is converted to fructose. Fructose is an intermediate product in the synthesis of glucosamine from glucose, and glucosamine is linked to regulation of trophoblast cell proliferation through regulation of mTOR. These findings suggest a link between glucose, fructose, glucosamine synthesis, GAG production, and placental m

关键词： Glycosaminoglycans Nutrient transport Placenta

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Streamlining the preparation of “endotoxin-free” clearcoli cell extract with autoinduction media for cell-free protein synthesis of the therapeutic protein crisantaspase

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Synthetic and Systems Biotechnology 2019年第4期4卷 220-224页

作者： J.Porter Hunt Emily Long Zhao Mehran Soltani Madison Frei J.Andrew D.Nelson bradley c.Bundy Department of chemical Engineering Brigham Young UniversityProvoUTUSA Department of chemical Engineering Brigham Young University330N Engineering BuildingProvoUT84602USA

An“endotoxin-free”***-based cell-free protein synthesis system has been reported to produce therapeutic proteins rapidly and ***,preparation of the most complex cFPS reagent–the cell extract–remains time-consuming and labor-intensive because of the relatively slow growth kinetics of the endotoxin-free clearcoliTMBL21(DE3)*** we report a streamlined procedure for preparing *** cell extract from clearcoli™using auto-induction *** this work,the term auto-induction describes cell culture media which eliminates the need for manual induction of protein *** clearcoli™cells in autoinduction media significantly reduces the hands-on time required during extract preparation,and the resulting“endotoxinfree”cell extract maintained the same cell-free protein synthesis capability as extract produced with traditional induction as demonstrated by the high-yield expression of crisantaspase,an FDA approved leukemia *** is anticipated that this work will lower the barrier for researchers to enter the field and use this technology as the method to produce endotoxin-free ***-based extract for cFPS.

关键词： Auto-induction Autoinduction cell-free protein synthesis cFPS Endotoxin-free crisantaspase clearcoli

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Understanding chinese international college and university students' physical activity behavior

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Journal of Sport and Health Science 2015年第2期4卷 203-210页

作者： Zi Yan bradley J.cardinal Alan c.Acock Department of Health Sciences-N8 Merrimack College college of Public Health and Human Sciences Oregon State University

Objective： To examine factors of the youth physical activity promotion （YPAP） model that are associated with chinese international students＇ meeting PA recommendations （MPAR）. Methods： A total of 649 （females = 320, males = 329） chinese international college students participated in the study. This study was conducted in the United States （US.） between June and August in 2011. Participants completed an online survey regarding their demographic, PA, predisposing, enabling, and reinforcing factors. Results： Logistic nested-regression analysis suggested that being male, having a higher body mass index, perceived competence, self-efficacy, attitude, and enjoyment all increased （p 〈 0.001） the participants＇ odds of MPAR. Except language barriers, all of the enabling and reinforcing factors predicted MPAR indirectly through the predisposing factors （p 〈 0.001）. conclusion： Understanding factors that influence PA among chinese international students is an important step in the process of promoting their long-term health and wellbeing. Designing program that address the identified key factors may help colleges and universities achieve this goal.

关键词： Health behavior Health promotion Higher education Youth physical activity promotion model

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Refrigerated and frozen storage impact aronia berry quality

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Food Production, Processing and Nutrition 2022年第1期4卷 13-24页

作者： Erica S.King Andrea Noll Susan Glenn bradley W.Bolling Department of Food Science University of Wisconsin-Madison1605 Linden Dr.MadisonWI53706USA Department of Statistics Medical Sciences CenterUniversity of Wisconsin-Madison1300 University Ave Rm 1220MadisonWI53706USA

Postharvest storage of many freshly picked berries affects polyphenol and sugar content. However, little is known about the impact of refrigerated and frozen storage on aronia berry composition. Therefore, the objective of this study was to characterize how storage at 4 ± 2 °c and − 20 ± 2 °c, and temperature cycles affect aronia berry polyphenols, total solid content, pH, titratable acidity, polyphenol oxidase (PPO) activity, sugar content, acid content, color, and cell structure. Refrigerated storage reduced proanthocyanidins (21%), anthocyanins (36%), and total phenols (21%) after 12 weeks. Frozen storage increased polyphenols in the first 6 mo. of frozen storage but then decreased polyphenols at mo. 8 to levels similar to initial values. Frozen temperature cycling reduced anthocyanins 18% but did not affect total phenols or proanthocyanidins. Scanning electron microscopy analysis indicated temperature cycling induced cell damage, shrinking, and fusion. This disruption led to the release of anthocyanins inside the berry tissue. PPO activity did not significantly correlate with the decrease in polyphenol content during storage. °Brix did not significantly change during refrigeration and frozen storage but did during the 12th temperature cycle. Aronia berries’ pH and titratable acidity were affected more by refrigeration than frozen and temperature storage. The pH increased by 4% during refrigeration, and titratable acidity decreased by 17% at 12 weeks. In conclusion, refrigerated storage results in a modest reduction of aronia berry polyphenols, but absolute extractable polyphenols are stable for up to 8 months of frozen storage.

关键词： Aronia berry Polyphenols Storage Refrigeration Sugars Acids Frozen

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DNA末端定量及其应用的研究

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生物化学与生物物理进展 2000年第5期27卷 528-533页

作者：彭黎明江虹 J.J.LIUc.J.bradley 华西医科大学附属第一医院医检专业成都610041 Department of Pathology Univesity of Melbourne Austin Hospital

为定量DNA断裂末端评价DNA的降解程度 ,以饱和标记 (TdT)法定量DNA末端最大标记量 (Lmax) ;并用流式细胞分析 (FcA)、原位DNA末端标记 (TUNEL)和琼脂糖电泳检测或标记DNA降解片段 .结果发现 :a TdT法最低检测限 5ngDNA ,线性范围为 5～ ... 详细信息

为定量DNA断裂末端评价DNA的降解程度 ,以饱和标记 (TdT)法定量DNA末端最大标记量 (Lmax) ;并用流式细胞分析 (FcA)、原位DNA末端标记 (TUNEL)和琼脂糖电泳检测或标记DNA降解片段 .结果发现 :a TdT法最低检测限 5ngDNA ,线性范围为 5～ 5 0 0 0ng ,较检测DNA降解片段的琼脂糖电泳敏感 2 0 0倍以上 ;b 地塞米松 (DEX)诱导淋巴瘤 (Raji)细胞凋亡产生的Lmax呈DEX剂量与诱导时间依赖性增加 ;c 自发性高血压大鼠 (SHR)心肌的Lmax呈年龄依赖性增加并与正常对照鼠 (WKY)相比差异非常显著 (P cA、TUNEL或电泳分析的相关性良好 (r >0 98) .TdT法定量Lmax敏感、特异、准确 ,可应用于分子生物学、细胞生物学。

关键词： DNA末端饱和标记 DNA降解细胞凋亡 TdT法

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Patterns of color phase indicate spawn timing at a Nassau grouper Epinephelus striatus spawning aggregation

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current Zoology 2012年第1期58卷 73-83页

作者： Archer, Stephanie K. skraftarcher@*** Heppell, Scott A. Semmens, Brice X. Pattengill-Semmens, christy V. Bush, Phillippe G. Mccoy, croy M. Johnson, bradley c. Department of Fisheries and Wildlife 104 Nash Hall Oregon State University Corvallis OR 97331 USA Reef Environmental Education Foundation (REEF) PO Box 246 Key Largo Fl 33037 USA Department of Environment Cayman Islands Government P.O. Box 486GT Grand Cayman Cayman Islands

Nassau grouper Epinephelus striatus are a large bodied, top level predator that is ecologically important throughout the caribbean. Although typically solitary, Nassau grouper form large annual spawning aggregations at predictable times in spe- cific locations. In 2003, The cayman Islands Marine conservation Board established protection for a newly rediscovered Nassau grouper spawning aggregation on Little cayman, British West Indies. The large size of this aggregation provides a unique oppor- tunity to study the behavior of Nassau grouper on a relatively intact spawning aggregation. During non-spawning periods Nassau grouper display a reddish-brown-and-white barred coloration. However, while aggregating they exhibit three additional color phases：＂bicolor＂, ＂dark＂, and ＂white belly＂. We video sampled the population on multiple days leading up to spawning across five spawning years. Divers focused a laser caliper equipped video camera on individual fish at the aggregation. We later ana- lyzed the video to determine the length of the fish and record the color phase. Our observations show that the relative proportion of fish in the bicolor color phase increases significantly on the day leading up to the primary night of spawning. The increase in the proportion of the bicolor color phase from 0.05 early in the aggregation to 0.40 on the day of spawning suggests that this color phase conveys that a fish is behaviorally and physiologically prepared to spawn. Additionally, 82.7% of fish exhibiting dark or white belly coloration early in the aggregation period suggests that these color phases are not only shown by female fish as was previously posited [current Zoology 58 （1）： 73-83, 2012].

关键词： Nassau grouper Epinephelus striatus Spawning aggregation Nuptial coloration Spawning behavior

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基于地理影响评估模型的我国对非农业援助的有效性检验

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统计与决策 2019年第21期35卷 93-96页

作者：陈玮冰武晋 bradley c.Parks 中国农业大学人文与发展学院北京100193 威廉玛丽学院AidData研究实验室美国威廉斯堡23185

对非洲农业援助一直是我国对外援助的重点领域,但其有效性及可持续性一直存在争议。文章运用地理影响评估模型,基于2001-2017年我国对36个非洲国家中的485个地区的农业援助项目和归一化植被指数(NDVI)数据,于我国对非农业援助的有效性... 详细信息

对非洲农业援助一直是我国对外援助的重点领域,但其有效性及可持续性一直存在争议。文章运用地理影响评估模型,基于2001-2017年我国对36个非洲国家中的485个地区的农业援助项目和归一化植被指数(NDVI)数据,于我国对非农业援助的有效性进行了整体性回归分析,并加入地区固定效应进行了有效性的可持续性检验。结果表明,我国对非农业援助整体上显著提高了受援国地区的农业生产能力;并且在项目开展后的第二年开始持续稳定地提升当地农业生产能力,说明项目具有较稳定的可持续性。

关键词：地理影响评估模型农业援助中非经济合作

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Pelvic region bone density,soft tissue mass,and injury frequency in female professional ballet dancers and soccer athletes

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Sports Medicine and Health Science 2021年第3期3卷 157-164页

作者： Hamed Vahedi carter M.Taft Joshua R.Daum Sherif Dabash Patrick c.Mcculloch bradley S.Lambert Department of Orthopedics&Sports Medicine Houston Methodist HospitalHoustonTXUnited States Department of Kinesiology Rice UniversityHoustonTXUnited States

We recently observed a high prevalence of low pelvic bone mineral density(BMD)in female professional ballet *** this population is susceptible to musculoskeletal overuse injuries,we aimed to determine which regions of the pelvis may be at greatest risk compared to general population females(GENPOP)as well as professional female soccer players(SOccER,a comparison to other elite athletes regularly subjected to high degrees of loading).Three groups of age-matched females[(GENPOP;n=38,27±1yrs),(BALLET;single com-pany,n=36,26±3yrs),(SOccER;single NWSL■club,n=34,25±1yrs)]consented to have their BMD and body composition assessed(DEXA,GE■).In addition to soft tissue and total and regional BMD analyses,a segmental analysis of the pelvis was performed to determine site-specific BMD for the iliac fossa,iliac fossa/iliac crest/ilium combined,pubic bone,ischium,and sacrum.A mixed-model ANOVA followed by a Tukey's post-hoc test was used to compare the groups(Type-I error;α=0.05).The BALLET group had lower pelvic BMD for all measures(Avg.%Diff.=15%-27%,pcompared to the SOccER group and for the ischium(Avg.%Diff.=8%;p=0.007)and sacrum(Avg.%Diff.=7%;p=0.028)compared to the GENPOP *** BALLET group had lower lean mass for all measures compared to the other groups(Avg.%Diff.=12%-18%;pced pelvic region soft tissue and site-specific BMD not previously detected using standard DEXA *** findings highlight which pelvic regions may benefit from preventative strength training and/or nutritional interventions.

关键词： Ballet Bone Bone density Athlete Female athlete

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