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自扭曲复合材料船用螺旋桨的可靠性设计和优化

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船舶与配套 2011年第9期 72-79页

作者： Michael R. Motley Yin l. Young Jack W. baker 普林斯顿大学土木环境工程系斯坦福大学土木环境工程系

研究目标是开发出一种基于可靠性的设计和优化方法，以提高自适应式复合材料螺旋浆的效率。目的是量化材料和操作不确定性对自适应螺旋浆性能的影响，并给出一种设计和优化方法，以使结构的性能和可靠性最大化。

关键词：可靠性设计复合材料船用螺旋桨优化扭曲自适应式不确定性螺旋浆

Efficacy of peroral endoscopic myotomy vs other achalasia treatments in improving esophageal function

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World Journal of Gastroenterology 2016年第20期22卷 4918-4925页

作者： Madhusudhan R Sanaka Umar Hayat Prashanthi N Thota Ramprasad Jegadeesan Monica Ray Scott l Gabbard Neha Wadhwa Rocio lopez Mark E baker Sudish Murthy Siva Raja Department of Gastroenterology Q3 Cleveland Clinic Department of Radiology Cleveland Clinic Department of Cardiothoracic Surgery Cleveland Clinic

AIM: To assess and compare the esophageal function after peroral endoscopic myotomy(POEM) vs other conventional treatments in ***: Chart review of all achalasia patients who underwent POEM, laparoscopic Heller myotomy(lHM) or pneumatic dilation(PD) at our institution between January 2012 and March 2015 was performed. Patient demographics, type of achalasia, prior treatments, pre- and post-treatment timed barium swallow(TBE) and high-resolution esophageal manometry(HREM) findings were compared between the three treatment groups. Patients who had both pre- and 2 mo posttreatment TBE or HREM were included in the final analysis. TBE parameters compared were barium column height, width and volume of barium remaining at 1 and 5 min. HREM parameters compared were basal lower esophageal sphincter(lES) pressures and lES-integrated relaxation pressures(IRP). Data are presented as mean ± SD, median [25th, 75 th percentiles] or frequency(percent). Analysis of variance, KruskalWallis test, Pearsons χ~2 test and Fishers Exact tests were used for ***: A total of 200 achalasia patients were included of which 36 underwent POEM, 22 underwent PD and 142 underwent lHM. POEM patients were older(55.4 ± 16.8 years vs 46.5 ± 15.7 years, P = 0.013) and had higher BMI than lHM(29.1 ± 5.9 kg/m^2 vs 26 ± 5.1 kg/m^2, P = 0.012). More number of patients in POEM and PD groups had undergone prior treatments compared to lHM group(72.2% vs 68.2% vs 44.3% respectively, P = 0.003). At 2 mo post-treatment, all TBE parameters including barium column height, width and volume remaining at 1 and 5 min improved significantly in all three treatment groups(P = 0.01 to P lumn height at 1 min in PD group(P = 0.11). At 2 mo post-treatment, there was significant improvement in basal lES pressure and lES-IRP in both lHM(40.5 mm Hg vs 14.5 mm Hg and 24 mm Hg vs 7.1 mm Hg respectively, P < 0.001) and POEM groups(38.7 mm Hg vs 11.4 mm Hg and 23.6 mm Hg vs 6.6 mm Hg res

关键词： Achalasia Dysphagia Heller myotomy Peroral endoscopic myotomy Manometry Pneumatic dilation

Bacterial Transfer from Hands While Eating Popcorn

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Food and Nutrition Sciences 2015年第15期6卷 1333-1338页

作者： Kimberly A. baker Inyee Y. Han J. Bailey lauren Johnson Edward Jones Amy Knight Mollye MacNaughton Peter Marvin Katherine Nolan Rose Martinez-Dawson Paul l. Dawson Department of Food Nutrition and Packaging Sciences Clemson University Clemson SC USA Department of Mathematical Sciences Clemson University Clemson SC USA

Popcorn is a very social food, often shared with others and offered at many major sporting events, concerts, movies, and fairs. However, sharing may not be safe since microorganisms found on hands may be transferred onto the shared popcorn. This study was conducted to determine if bacteria are transferred from hands to popcorn during handling. Over 30 samplings revealed that bacterial transfer to popcorn from hands was very low;however transfer did occur with large variation between subjects. Since hands and surfaces can carry bacteria in situations where food is being shared, transferring bacteria from one person to another person is always a risk.

关键词： Component Popcorn Bacterial Transfer Food Safety Sharing Food

体外缺氧诱导子痫前期滋养细胞模型优化及代谢组学鉴定

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重庆医科大学学报 2017年第8期42卷 1045-1052页

作者：杨晓涛韩顶立 Philip N.baker 漆洪波童超杨竹重庆医科大学附属第二医院妇产科重庆医科大学"中国-加拿大-新西兰"联合母胎医学实验室重庆400010

目的:探讨滋养细胞体外缺氧不同处理方法模拟子痫前期模型的优化研究。方法:HTR8/SVneo滋养细胞分别在1%O2(缺氧环境)和21%O2(常氧环境)培养箱中培养1 h(记为H1、N1)或2 h(记为H2、N2),缺氧1 h后复氧1 h(记为H1R1)和缺氧2 h后复氧2 h(记... 详细信息

目的:探讨滋养细胞体外缺氧不同处理方法模拟子痫前期模型的优化研究。方法:HTR8/SVneo滋养细胞分别在1%O2(缺氧环境)和21%O2(常氧环境)培养箱中培养1 h(记为H1、N1)或2 h(记为H2、N2),缺氧1 h后复氧1 h(记为H1R1)和缺氧2 h后复氧2 h(记为H2R2),H1R1后再缺氧1 h(记为H1R1H1),H2R2后再缺氧2 h(记为H2R2H2),H1R12个循环(记为H1R1H1R1)和H2R22个循环(记为H2R2H2R2),缺氧2 h后复氧6 h(记为H2R6),持续缺氧24 h,以及持续常氧4 h(记为N4)、8 h(记为N8)和24 h(记为Normoxia),然后提取蛋白以Western blot检测腺苷酸活化蛋白激酶(AMP-activated protein kinase,AMPK)磷酸化水平,以验证各组处理对于诱导滋养细胞能量应激的效果;HTR8/SVneo滋养细胞在常氧或者缺氧环境培养24 h后经气相质谱技术(gas chromatography mass spectrum,GS-MS)进行细胞代谢组学分析,以验证AMPK磷酸化水平上调是否与滋养细胞代谢组变化具有一致性。结果:缺氧组AMPK的活性(1.615±0.111)明显高于常氧组(1.000±0.107)和缺氧复氧组(1.277±0.113);缺氧时显著增加的代谢物有4-甲基-2-戊酮酸(log22.597为1.377)、水合乙醛酸(log22.483为1.312)、组氨酸(log21.188为0.248)、苯丙氨酸(log21.262为0.335)、缬氨酸(log21.518为0.602)、正亮氨酸(log21.519为0.603)、乙酰丝氨酸(log21.691为0.758)、丝氨酸(log21.783为0.834)、半胱氨酸(log21.851为0.889)、蛋氨酸(log22.072为1.051)、鸟氨酸(log22.251为1.170)等;而棕榈反油酸(log20.127为-2.983)、11,14,17-廿碳三烯酸(log20.334为-1.583)、二十四单烯酸(log20.600为-0.738)、共轭亚油酸(log20.680为-0.557)、顺式十八碳烯酸(log20.711为-0.492)、9-十七碳烯酸(log20.782为-0.355)、二十二碳六烯酸(log20.829为-0.271)、二十碳五烯酸(log20.841为-0.250)、芥酸(log20.844为-0.244)、二十二碳五烯酸(log20.898为-0.156)、柠檬酸(log20.279为-1.842)、苹果酸(log20.208为-2.264)、琥珀酸(log20.254为-1.980)、顺乌头酸(log20.260为-1.946)、β-柠檬酸-左旋谷氨酸(log20.093为-3.430)、β-丙氨酸(log20.139为-2.851)、胱硫醚(log20.267为-1.904)、顺式-4-羟脯氨酸(log20.500为-1.000)等在缺氧时显著降低。代谢途径结果分析显示缺氧时滋养细胞中核苷酸代谢[log2(1.811、1.149)分别为0.857、0.201]、能量代谢[log2(1.510、1.173、1.149)分别为0.595、0.230、0.201]、维生素代谢[log2(1.045、1.052、1.125)分别为0.064、0.073、0.170]、氨基酸代谢[log2(1.245、1.020、1.027、1.123、1.127、1.076)分别为0.316、0.028、0.039、0.167、0.173、0.106]、信号转导(log21.046为0.065)、蛋白翻译(log21.026为0.037)等途径被激活,而碳水化合物[log2(0.857、0.857、0.799)分别为-0.222、-0.222、-0.323]、脂肪酸[log2(0.944、0.912、0.826)分别为-0.083、-0.133、-0.276]、内分泌代谢[log2(0.885、0.799、0.799)分别为-0.176、-0.323、-0.323]和其他第二代谢物生物合成[log2(0.947、0.871、0.743)分别为-0.079、-0.199、-0.428]等代谢途径显著受到抑制。结论:单纯缺氧模型更适合用于子痫前期病理生理机制的体外研究。

关键词：子痫前期 HTR8/SVneo滋养细胞缺氧腺苷酸活化蛋白激酶气相质谱技术

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为每一个学生找到正确的学习时机

中国教育网络 2017年第9期 30-32页

作者： Jhon baker 陈强不详清华大学信息化工作办公室

本文是美国知名教育技术厂商D2l的总裁和首席执行官Jhon baker撰写的一篇评论，是在EDUCUASE在2015年发表的一份白皮书——《下一代数字学习环境：研究报告》（注：报告翻译可参阅本刊2015年12月刊）的基础上提出的一些新观点。该白皮... 详细信息

本文是美国知名教育技术厂商D2l的总裁和首席执行官Jhon baker撰写的一篇评论，是在EDUCUASE在2015年发表的一份白皮书——《下一代数字学习环境：研究报告》（注：报告翻译可参阅本刊2015年12月刊）的基础上提出的一些新观点。该白皮书针对现有的教学管理系统（lMS）的现状，提出了建设下一代数字学习环境的愿景，并指出了下一代数字学习环境应当具备的若干特征，提出了“乐高积木块”的比喻。

关键词：学习环境学生教学管理系统首席执行官教育技术白皮书代数木块

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管内外气体的冷却与减湿

硫酸工业 1966年第S1期 21-29页

作者： B.l.baker K.O.Beatty Jr 孙师白裘令秀 Univesity of South Carolina Columbia North Carolina State College Roleigh North Carolina State College Roleigh South Carolia North Carolina

自1934年以来,各国学者对不可冷凝气体和蒸汽的混合物的冷却,曾进行很多研究,探讨与之相应的传热传质的机理,总结成计算方法,以期应用。历年来各期刊学报上这方面专论是史不绝书的。一般计算均据柯尔本的热平衡试差法,惜其法计算时颇感... 详细信息

自1934年以来,各国学者对不可冷凝气体和蒸汽的混合物的冷却,曾进行很多研究,探讨与之相应的传热传质的机理,总结成计算方法,以期应用。历年来各期刊学报上这方面专论是史不绝书的。一般计算均据柯尔本的热平衡试差法,惜其法计算时颇感繁冗。后来各学者又提出改良方法,包括图解,以求简化,但亦不见很大简化。本文所提方法,是历来最简单的一种计算方法,概念新颖,便于应用。其法仅对一般有关传热的努塞尔特准数用一个热负荷此数(q/q)~x来修正之。当气体中不含蒸汽时,则比数等于1,过程即属于气体热传递。所以只要根据进出系统的气体热含量及所含蒸汽量,这是已知和要求的条件,即可一笔算出。这个比数的指数x,是可以据实验或实践求出的。由于文明生产的要求,晚近国际多倡议间接冷凝,但对相应的设计,始终苦无一个简化方法可资遵循,因译注此文,以供设计者参考,是抛砖引玉,求商榷的意思。

关键词：热传递气膜传热系数液膜翅管努塞尔特准数管壁温度比数传热率传热性质显热热力学性质垂直管热负荷蒸汽压凝液

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慢性砷暴露对小鼠脑和血清代谢组学的影响

南方医科大学学报 2016年第9期36卷 1192-1197页

作者：代华夏茵茵 Ting-li Han Philip N.baker 唐旭张瑞源杜航蔡同建程淑群重庆医科大学公共卫生与管理学院医学与社会发展研究中心健康领域社会风险预测治理协同创新中心重庆400016 奥克兰大学里金斯研究所新西兰奥克兰重庆市职业病防治院理化检验科重庆400060 第三军医大学军事预防医学院流行病学教研室重庆400038

目的观察慢性砷暴露对小鼠皮层及血清代谢组学的影响,探讨其神经毒性机制。方法将12只C57Bl/6J三周龄雄鼠,按体质量随机分为2组,暴露组饮用含50 mg/l亚砷酸钠水12周,对照组饮用蒸馏水。暴露结束后,采用氢化物发生一原子荧光光谱法测定... 详细信息

目的观察慢性砷暴露对小鼠皮层及血清代谢组学的影响,探讨其神经毒性机制。方法将12只C57Bl/6J三周龄雄鼠,按体质量随机分为2组,暴露组饮用含50 mg/l亚砷酸钠水12周,对照组饮用蒸馏水。暴露结束后,采用氢化物发生一原子荧光光谱法测定脑砷含量;气相色谱/质谱联用法(GC/MS)对砷暴露组和对照组小鼠皮层和血清进行代谢组学研究,运用主成分分析法(PCA)分析比较两组代谢产物的差异,两样本t检验筛选两组间差异性代谢产物,利用代谢途径在线分析工具查找其影响的相关代谢途径。结果砷暴露组脑砷含量高于对照组,差异具有统计学意义(P<0.05);砷暴露组大脑皮层中苯丙氨酸、酪氨酸、组氨酸、赖氨酸和柠檬酸含量升高,血清中丝氨酸、甘氨酸、脯氨酸、天门冬氨酸及谷氨酸含量升高,而α-酮戊二酸含量下降。PCA分析显示暴露组与对照组小鼠皮层和血清代谢特征存在差异,差异具有统计学意义(P<0.05)。结论慢性砷暴露可通过干扰皮层和血清氨基酸类代谢和三羧酸循环,导致神经递质合成障碍以及干扰能量代谢而影响中枢神经系统功能。

关键词：代谢组学砷暴露神经毒性主成分分析法

促甲状腺激素水平与体外受精孕妇妊娠结局的关系

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世界核心医学期刊文摘（妇产科学分册） 2006年第11期2卷 6-7页

作者： baker V.l. Rone H.M. Pasta D.J. 朱磊 Fertility Physicians of Northern California San Jose and Palo Alto CA United States Dr.

Objective: The aim of this study was to determine if pregnancy outcome for women undergoing in vitro fertilization is correlated with pre-conception thyroid-stimulating hormone level. Study design: We performed a retrospective cohort study of in vitro fertilization cycles in our private practice with an initial positive serum human chorionic gonadotropin level and thyroid-stimulating hormone level available (n = 364). We examined whether or not birth outcome differed between cycles in which the thyroid-stimulating hormone was > 2.5 mIU/l compared with cycles with a thyroid-stimulating hormone level of ≤ 2.5 mIU/l. logistic regression was used to determine the association between thyroid-stimulating hormone level and spontaneous abortion rate. Results: Delivery outcome was available for 195 cycles, 36% of which had a thyroid-stimulating hormone level > 2.5. The gestational age at delivery was higher in cycles with a thyroid-stimulating hormone ≤ 2.5 than for cycles with a thyroid-stimulating hormone > 2.5 (38.5 vs 38.0 weeks for singletons, 36.0 vs 34.6 weeks for twins, overall P = .012 for thyroid-stimulating hormone level). The mean birth weight for cycles with a thyroid-stimulating hormone ≤ 2.5 was higher than for cycles with a thyroid-stimulating hormone > 2.5 (7.33 vs 6.78 lbs for singletons, P = .024 and 5.36 vs 4.83 lbs for twins, P = .023). Restricting analysis to cycles where the woman was not taking thyroid replacement did not change the overall conclusions. There was a trend toward increasing risk of miscarriage with increasing thyroid-stimulating hormone level in nondonor cycles, controlling for age and day 3 follicle-stimulating hormone level, but this trend did not reach statistical significance. Conclusion: A pre-conce-ption thyroid-stimulating hormone level > 2.5 mIU/l is associated with a lower gestational age at delivery and lower birth weight in women undergoing in vitro fertilization.

关键词：体外受精妊娠结局甲状腺激素水平自然流产率卵泡刺激素促甲状激素胎孕分娩结局回顾性队列研

Steady state heat transfer analysis in a rectangular moving porous fin

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Propulsion and Power Research 2020年第2期9卷 188-196页

作者： Partner l.Ndlovu Raseelo J.Moitsheki School of Computer Science and Applied Mathematics University of the WitwatersrandJohannesburgPrivate Bag 3Wits2050South Africa Standard Bank of South Africa.30 baker Street RosebankJohannesburg2196South Africa

In this article,the variation of temperature distribution and fin efficiency in a porous moving fin of rectangular profile is *** study is performed using Darcy's model to formulate the governing heat transfer differential *** approximate analytical solution is generated using the variational iteration method(VIM).The power series solution is validated by benchmarking it against the numerical solution obtained by applying the Runge-Kutta fourth order method.A good agreement between the analytical and numerical results is *** effects of porosity parameter,Peclet number and other thermo-physical parameters,such as the power index of heat transfer coefficient,convective-conductive parameter,radiative-conductive parameter,thermal conductivity gradient and non-dimensional ambient temperature on non-dimensional temperature are also studied and *** results indicate that the fin rapidly dissipates heat to the ambient temperature with an increase in the Peclet number,convection-radiation parameters and the porosity parameter.

关键词： Heat transfer Moving porous Darcy’s model Variational iteration method(VIM) Fin tip temperature