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Direct detection and measurement of wall shear stress using a filamentous bio-nanoparticle

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Nano Research 2015年第10期8卷 3307-3315页

作者： Daniela P. Lobo Alan M. Wemyss David J. Smith Anne Straube Kai B. Betteridge Andrew H. J. Salmon rebecca R. Foster Hesham e. elhegni Simon C. Satchell Haydn A. Little Raul Pacheco-Gomez Mark J. Simmons Matthew R. Hicks David O. Bates Alison Rodger Timothy R. Dafforn Kenton P. Arkill DepartmentofChemistryandWarwickAnalyticalScienceCentre UniversityofWarwickCoventryCV47ALUK MOACDoctoralTrainingCentre UniversityofWarwickCoventryCV47ALUK Mathematics UniversityofBirminghamEdgbastonBirminghamWestMidlandsB152TTUK CentreforMechanochemicalCellBiology WarwickMedicalSchoolUniversityofWarwickCoventryCV47ALUK PhysiologyandPharmacology UniversityofBristolUniversityWalkBristolBS81TDUK ClinicalSciences WhitsonStreetUniversityofBristolBristolBS13NYUK SchoolofChemistry UniversityofBirminghamEdgbastonBirminghamWestMidlandsB152TTUK Biosciences UniversityofBirminghamEdgbastonBirminghamWestMidlandsB152TTUK Chemicalengineering UniversityofBirminghamEdgbastonBirminghamWestMidlandsB152TTUK SchoolofMedicine UniversityofNottinghamQueen'sMedicalCentreNottinghamNG27UHUK Biochemistry UniversityofBristolUniversityWalkBristolBS81TDUK

The wall shear stress （WSS） that a moving fluid exerts on a surface affects many processes including those relating to vascular function. WSS plays an important role in normal physiology （e.g. angiogenesis） and affects the microvasculature＇s primary function of molecular transport. Points of fluctuating WSS show abnormalities in a number of diseases; however, there is no established technique for measuring WSS directly in physiological systems. All current methods rely on estimates obtained from measured velocity gradients in bulk flow data. In this work, we report a nanosensor that can directly measure WSS in microfluidic chambers with sub-micron spatial resolution by using a specific type of virus, the bacteriophage M13, which has been fluorescently labeled and anchored to a surface. It is demonstrated that the nanosensor can be calibrated and adapted for biological tissue, revealing WSS in micro-domains of cells that cannot be calculated accurately from bulk flow measurements. This method lends itself to a platform applicable to many applications in biology and microfluidics.

关键词： microfluidics nanoparticle M13 bacteriophage wall shear stress fluorescent microscopy

鱼眼中的世界 AF-S鱼眼尼克尔8-15mm f/3.5-4.5e eD

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摄影之友 2017年第8期 152-153页

作者：金属魔力 rebecca

习惯了稀松平常的视角，想找个有意思的镜头来拍摄？这次我们的摄影师拿着尼康最新发布的AF-S鱼眼尼克尔8—15mm f／3．5-4．5e eD镜头，看看这支视角可以达到180度的鱼眼镜头下，会有怎样的奇特画面。

关键词：鱼世界镜头摄影师拍摄

Reproductive Health Needs of Women Living with HIV/AIDS in Yaounde, Cameroon

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World Journal of AIDS 2014年第1期4卷 8-14页

作者： Robinson e. Mbu William A. Takang Hortence J. Fouedjio ekane Joan Flobert Y. Fouelifack Florence N. Tumasang rebecca N. Tonye Robert J. I. Leke Department of Obstetrics and Gynecology Faculty of Health Sciences University of Bamenda Bamenda Cameroon Department of Obstetrics and Gynecology Faculty of Medicine and Biomedical Sciences University of Yaounde 1 Yaounde Cameroon Department of Obstetrics and Gynecology Faculty of Medicine and Biomedical Sciences University of Yaounde 1 Yaounde Cameroon Maternity Unit Central Hospital Yaounde Cameroon Maternity Unit Central Hospital Yaounde Cameroon

The population plagued with the HIV/AIDS pandemic in Cameroon is young, a generation that may desire or control fertility. For those who may become pregnant, the desire to have children may not be there. We carried out this study to look at the picture of the reproductive health needs of women living with HIV/AIDS in our setting. In this cross-sectional non-analytic design that lasted for three years, we employed both qualitative and quantitative methods to collect data from them after receiving ethical clearance (N221/CM/2009) from the National ethics Committee. Consenting HIV infected women who were attending the “HIV Day Care” clinics and those who delivered and were in the post partum wards in four of our major hospitals in Yaounde were enrolled. Interviews were individualized. We used both CSPro version 4.1 and Statistical Package for Social Sciences (SPSS) version 19.0 softwares for data analysis. Four hundred and fifteen (415) women were enrolled;the mean age was 29 ± 7.8 years;the most represented age group was 24 -29 years. They were single (36.14%), well educated (5 out of 10 had attained university level of education), 61.20% revealed that their partners knew their HIV status, 82.4% believed that screening for cancer of the cervix was necessary for their status and 47.70% would want to be screened for some or all STIs. About 36.86% had the desire to have children, 57.1% of those who delivered did not plan to have the pregnancies out of which 82% would have wanted a modern method of contraception but did not have (82% unmet needs). Modern contraceptive use was associated with age and individual characteristics such as level of education. It was 64.34% among women who had secondary level of education and below as against 35.66% among those who had high school level of education and above. Contraceptive use was also high among women who were unmarried as against those who were married (89.64% vs 10.36%). The desire to have children decreased as age increased

关键词： Reproductive Health Needs Family Planning Unmet Needs Cancer of the Cervix Sexually Transmitted Infections

Principles for managing marine ecosystems prone to tipping points

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ecosystem Health and Sustainability 2015年第5期1卷 15-32页

作者： Kimberly A.Selkoe Thorsten Blenckner Margaret R.Caldwell Larry B.Crowder Ashley L.erickson Timothy e.essington James A.estes Rod M.Fujita Benjamin S.Halpern Mary e.Hunsicker Carrie V.Kappel Ryan P.Kelly John N.Kittinger Phillip S.Levin John M.Lynham Megan e.Mach rebecca G.Martone Lindley A.Mease Anne KSalomon Jameal F.Samhouri Courtney Scarborough Adrian C.Stier Crow White Joy Zedler National Center for ecological Analysis and Synthesis 735 State StreetSuite 300Santa BarbaraCalifornia 93101 USA Hawaii Institute of Marine Biology University of HawaiiKaneoheHawaii 96744 USA Stockholm Resilience Centre Stockholm UniversityKra¨ftriket 2B10691 StockholmSweden Center for Ocean Solutions Stanford Woods Institute for the EnvironmentStanford University473 Via Ortega Room 193StanfordCalifornia 94305 USA School of Aquatic and Fishery Sciences University of WashingtonSeattleWashington 98195 USA Department of ecology and evolutionary Biology 100 Shaffer RoadUniversity of CaliforniaSanta CruzCalifornia 95060 USA environmental Defense Fund 123 Mission Street28th FloorSan FranciscoCalifornia 94105 USA Bren School of environmental Science and Management University of CaliforniaSanta BarbaraCalifornia 93106 USA Imperial College London Silwood Park CampusBuckhurst RoadAscot SL57PY United Kingdom School of Marine and environmental Affairs University of Washington3707 Brooklyn Avenue NESeattleWashington 98105-6715 USA Conservation International Betty and Gordon Moore Center for Science and Oceans7192 Kalaniana‘ole HighwaySuite G230HonoluluHawaii 96825 USA Conservation Biology Division Northwest Fisheries Science CenterNational Marine Fisheries ServiceNational Oceanic and Atmospheric Administration2725 Montlake Boulevard EastSeattleWashington 98112 USA Department of economics University of Hawaii at ManoaHonoluluHawaii 96822 USA School of Resource and environmental Management Simon Fraser UniversityBurnabyBritish Columbia V5A1S6 Canada Department of Biological Sciences California Polytechnic State UniversitySan Luis ObispoCalifornia 93407 USA Botany Department University of WisconsinMadisonWisconsin 53706 USA

As climatic changes and human uses intensify,resource managers and other decision makers are taking actions to either avoid or respond to ecosystem tipping points,or dramatic shifts in structure and function that are often costly and hard to *** indicates that explicitly addressing tipping points leads to improved management *** on theory and examples from marine systems,we distill a set of seven principles to guide effective management in ecosystems with tipping points,derived from the best available *** principles are based on observations that tipping points(1)are possible everywhere,(2)are associated with intense and/or multifaceted human use,(3)may be preceded by changes in earlywarning indicators,(4)may redistribute benefits among stakeholders,(5)affect the relative costs of action and inaction,(6)suggest biologically informed management targets,and(7)often require an adaptive response to *** suggest that early action to preserve system resilience is likely more practical,affordable,and effective than late action to halt or reverse a tipping *** articulate a conceptual approach to management focused on linking management targets to thresholds,tracking early-warning signals of ecosystem instability,and stepping up investment in monitoring and mitigation as the likelihood of dramatic ecosystem change *** approach can simplify and economize management by allowing decision makers to capitalize on the increasing value of precise information about threshold relationships when a system is closer to tipping or by ensuring that restoration effort is sufficient to tip a system into the desired regime.

关键词： critical transition ecosystem-based management marine spatial planning nonlinear relationships restoration ecology stakeholder engagement

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从电商视角看青州市中小企业的发展

中国商论 2021年第21期 63-66页

作者：汪珍英 rebecca Miranda 碧瑶大学工商管理(菲律宾碧瑶市) 潍坊理工学院

电子商务为大城市企业带来的成功影响已经得到证实。而在中国,地域之间的经济发展并不平衡,小城市的中小企业电子商务的发展与大城市的中小企业相比,具有自身的特点。电子商务是否为小城市的中小企业带来同样的影响并没有得到适当研究... 详细信息

电子商务为大城市企业带来的成功影响已经得到证实。而在中国,地域之间的经济发展并不平衡,小城市的中小企业电子商务的发展与大城市的中小企业相比,具有自身的特点。电子商务是否为小城市的中小企业带来同样的影响并没有得到适当研究。本文以山东省青州市为例,开展了电商对小城市中小企业发展的研究。通过设定李克特五级量表,对指标分值及对应信息进行描述,收集山东省青州市中小企业数据样本。同时,从企业管理者因素、技术因素、企业战略、客户、供应商、网站性能因素分析中小企业电商成功的影响因素,为青州市中小企业电子商务发展提供了参考意义。

关键词：电子商务影响因素李克特五级量表中小企业青州市

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effects of gestational weight gain on the outcome of labor at the Yaounde central hospital maternity, Cameroon

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Open Journal of Obstetrics and Gynecology 2013年第9期3卷 648-652页

作者： Robinson e. Mbu Hortence J. Fouedjio Mpey Tabot Fluorbert Y. Fouelifack Florence N. Tumasang rebecca N. Tonye Robert J. I. Leke Department of Obstetrics and Gynecology Faculty of Medicine and Biomedical Sciences University of Yaounde 1 Cameroon Maternity Unit Central Hospital Yaounde Cameroon

Obesity rates are increasing in Cameroon. Obstetric literature has recently focused on the rising incidence of complications with increases in weight gain in pregnancy. Some of these complications include gestational diabetes, hypertensive disorders, operative deliveries, genital tract lacerations and fetal birth trauma. examining the effects of excess weight gain during the course of pregnancy could help identify weight gain limits. The Institute of Medicine (IOM) was recommended by the World Health Organization (WHO) to develop guidelines for weight gain during pregnancy and we designed this study in order to determine delivery outcomes when weight is gained above these guidelines. We also sought to know if these guidelines are applicable in our environment. In this cross-sectional analytic design, pre-pregnancy and intra-partum BMIs were calculated for all the parturients who consented. They were classified into normal weight gain and excessive weight gain based on IOM recommendations. Those in the normal weight gain group were women with BMIs that ranged between 18.5 kg/m2 and 30 kg/m2 and who gained 9 - 16 kgs. Those who gained weight above these range were considered as having gained excessive weight during pregnancy. They were all follow-up in labor using the partogram. We compared prepartum, intra-partum and post-partum outcomes in the two groups by calculating odds ratios (ORs), 95% confidence intervals and p values. One hundred and ten (110) overweight women were matched against the same number of women who had normal weight gain. There was no significant difference between social status, marital status as well as level of educational and weight gain in the two groups. Underweight (BMI p = 0.048). Women who gained weight above the recommended range suffered from preeclampsia 18.2% vs. 6.4% (OR 3.2, 95% CI 1.3 - 8.0, p = 0.014), higher cesarean section rates 27.3% vs. 10% (OR 3.3, 95% CI 1.5 - 7.1, p = 0.002), higher rates of induced labor 19.1% vs. 9.0% (O

关键词： Obesity Rate Gestational Weight Gain Pregnancy

我国部分医院ST段抬高急性冠状动脉综合征再灌注治疗登记研究

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中华心血管病杂志 2006年第7期34卷 593-597页

作者：于丽天朱俊 rebecca Mister 章晏李建冬王多劳刘力生 Marcus Flather 阜外心血管病医院心内科北京100037 澳大利亚悉尼大学NH&MRC临床试验中心英国伦敦London School of Hygiene & Tropical Medicine 英国伦敦Royal Brompton Hospital临床试验与评价中心

目的了解目前我国ST段抬高急性冠状动脉综合征(ACS)再灌注治疗实施状况及近期预后。方法入选来自5个地区不同级别(从中心城市的三级医院到县级医院)20个中心的ST段抬高ACS或怀疑为新出现的左束支传导阻滞的患者共518例,对其临床特点,再... 详细信息

目的了解目前我国ST段抬高急性冠状动脉综合征(ACS)再灌注治疗实施状况及近期预后。方法入选来自5个地区不同级别(从中心城市的三级医院到县级医院)20个中心的ST段抬高ACS或怀疑为新出现的左束支传导阻滞的患者共518例,对其临床特点,再灌注治疗情况及预后进行评价,并进行3个月随访。其中男371例,女147例,平均年龄(65±11)岁。随访率为99．6％。结果患者自症状开始到就诊的中位数时间为4 h,20％的患者在症状出现12 h以上就诊。292例(56％,292／518)ST段抬高ACS患者接受了再灌注治疗,其中134例(46％,134／292)接受了急诊冠状动脉介入(PCI)治疗,158例(54％,158／292)为溶栓治疗,溶栓治疗中尿激酶的应用占67％。从就诊到开始PCI的中位数时间(door-to-cath)为110 min,从患者就诊到开始溶栓的中位数时间为65 min。多因素回归分析显示,高龄(≥75岁,P<0．01)、有心肌梗死病史(P<0．01)及心力衰竭病史(P< 0．05)是未接受再灌注治疗的预测因素。非再灌注治疗组出院(P<0．01)和3个月病死率(P< O．01)、出院(P<0．01)和3个月心力衰竭发生率(P<0．01),以及3个月死亡或再梗死和死亡或再梗死或卒中的联合事件发生率(均P<0．01)均明显高于再灌注治疗组,但不同的再灌注治疗方法对近期预后无明显影响。相似的结果也见于症状出现12 h以内就诊患者的亚组分析。结论再灌注治疗是改善ST段抬高ACS患者预后的关键措施。我国ST段抬高ACS再灌注治疗有待于进一步提高,不仅要提高再灌注治疗率,更应缩短就诊和再灌注治疗前的延误时间,并加强高危患者的再灌注治疗。

关键词：冠状动脉疾病心肌再灌注

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学前儿童基于物体重量归纳推理的发展:中美跨文化比较

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心理学报 2018年第12期50卷 1381-1389页

作者：王志丹周爱保张荣华卜梦瑾李玉雯王海静 Williamson rebecca 江苏师范大学教育科学学院徐州221116 西北师范大学心理学院兰州730070 美国佐治亚州立大学心理系亚特兰大30302

关于物体重量认知的研究是探讨儿童整个认知发展的重要途径之一。本文通过两个实验考察了美国和中国儿童利用语言标签基于重量进行归纳推理的发展特点及跨文化一致性。实验人员利用语言标签提示三个外部知觉特征完全相似物体中的一个物... 详细信息

关于物体重量认知的研究是探讨儿童整个认知发展的重要途径之一。本文通过两个实验考察了美国和中国儿童利用语言标签基于重量进行归纳推理的发展特点及跨文化一致性。实验人员利用语言标签提示三个外部知觉特征完全相似物体中的一个物体,随后要求儿童从剩余两个物体中选择一个他们认为和目标物体共享语言标签的物体。研究考察儿童是否能够基于物体的内在属性重量进行类别判断。结果显示:(1) 4岁和5岁儿童以重量进行归纳推理显著高于3岁儿童, 4岁和5岁儿童之间的差异不显著;(2)美国和中国4岁和5岁儿童的表现均显著高于随机水平, 3岁儿童与随机水平没有显著差异;(3)美国2岁儿童的表现边缘低于随机水平, 6岁儿童显著高于随机水平。总之,儿童利用语言标签进行基于重量的归纳推理随年龄增长而发展;美国和中国儿童在发展特点及年龄转折上具有跨文化一致性, 4岁儿童具备了利用语言标签进行基于物体内在属性归纳推理的能力。

关键词：重量归纳推理内在属性跨文化一致性

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evaluation of Acute and Sub-Acute Oral Toxicities of Momordica foetida Schumach. (Cucurbitaceae) Leaves Methanol extract in Wistar Rats

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Journal of Biosciences and Medicines 2023年第1期11卷 123-142页

作者： Cedric Laurel Cidjeu Pouaha Landry Lienou Lienou Fabrice Fabien Dongho Dongmo Colette elysée Aboudi etono Raphael Tchientcheu Azaber Masoohe Mamoune Sandrine Suzanne Beack Bayengue rebecca Madeleine ebelle etame Rosalie Anne Ngono Ngane Faculty of Science University of Douala Douala Cameroun Institute of Medical Research and Medicinal Plant Studies (IMPM) Yaounde Cameroon

Momordica foetida is a plant widely used in tropical Africa to manage gastroenteric diseases. Previous studies demonstrated interesting antibacterial activity against human pathogenic bacteria. However, the security or toxicity of methanol leaf extract has not been determined yet. The aim of this study was to evaluate the acute and sub-acute toxicity of the leaf extract of Momordica foetida. In the acute toxicity study, a single oral dose of 5000 mg/kg body weight was administered to rats which were observed for 14 days in order to identify signs of toxicity or death. In the sub-acute toxicity, the animals were treated with 250, 500 and 1000 mg/kg of the extract for 28 consecutive days. Body weights and behavior were noted throughout the experiment. Upon treatment, blood and urine were collected for hematological and biochemical analysis. Liver, lungs, heart, kidneys, testes and ovaries were analyzed for relative weights and histopathology. The acute toxicity study of M. foetida leaf extract revealed no signs of toxicity related to the treatment, indicating that the median-lethal-dose (LD50) value is greater than 5000 mg/Kg of body weight. In the sub-acute toxicity assay, the extract did not affect the general behavior of animals, meanwhile, it led to a significant increase in the levels of red blood cells, platelets, hemoglobin, granulocytes and Mid-Cells (MIDs). Biochemical parameters showed an increase in total cholesterol, HDL cholesterol, serum urea, serum and urinary glucose and a decrease in urinary proteins, serum creatinine, urinary urea levels, serum activities of AST, ALT and proteins levels, as well as increases in lung, spleen and ovaries relative weight were noticed, all compared to control animals. Histological analysis revealed a normal architecture of kidneys, liver, heart, lung, ovaries and testes. This study provides valuable data on the safety of per os administration of Momordica foetida leaf methanol extract that could be very useful for future

关键词： Momordica foetida Acute Toxicity Sub-Acute Toxicity Biochemical Parameters Hematological Parameters