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胸部CT中气道的性别差异:COPD基因队列研究

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国际医学放射学杂志 2023年第1期46卷 112-113页

作者： S.P.Bhatt S.Bodduluri A.Nakhmani Y.Kim j.M.Reinhardt e.A.Hoffman 张颖

摘要女性慢性阻塞性肺疾病(COPD)的发病率正快速接近男性,并且女性症状更严重。虽然肺气肿的性别差异已有报道,气道的性别差异尚未见系统研究。目的评估气道是

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Systematic evaluation of a holmium:yttrium-aluminum-garnet laser lithotripsy device with variable pulse peak power and pulse duration

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Asian journal of Urology 2014年第1期1卷 60-65页

作者： Christopher Netsch Sophie Knipper Christian Tiburtius Andreas j.Gross Department of Urology Asklepios Hospital BarmbekHamburgGermany

Objective:The Holmium:yttrium-aluminum-garnet(Ho:YAG)laser is the standard lithotrite for *** paper is to evaluate a Ho:YAG laser with a novel effect function in vitro,which allows a real-time variation of pulse duration and pulse peak ***:Two types of phantom calculi with four degrees of hardness were made for fragmentation and retropulsion *** was analysed at 5(0.5 j/10 Hz),10(1 j/10 Hz),and 20(2 j/10 Hz)W in non-floating phantom calculi,retropulsion in an ureteral model at 10(1 j/10 Hz)and 20(2 j/10 Hz)W using floating phantom *** effect function was set to 25%,50%,75%,and 100%of the maximum possible effect function at each power *** outcomes:fragmentation(mm^3),the distance of retropulsion(cm);5 measurements for each ***:An increase of the effect feature(25%vs.100%),i.e.,an increase of pulse peak power and decrease of pulse duration,improved Ho:YAG laser *** effect was remarkable in soft stone composition,while there was a trend for improved fragmentation with an increase of the effect feature in hard stone *** increased with increasing effect function,independently of stone *** major limitations of the study are the use of artificial stones and the in vitro ***:Changes in pulse duration and pulse peak power may lead to improved stone fragmentation,most prominently in soft stones,but also lead to increased *** new effect function may enhance Ho:YAG laser fragmentation when maximum power output is limited or retropulsion is excluded.

关键词： Ureteroscopy Ho:YAG laser Lithotripsy Pulse peak power Pulse duration

On the operating speed and energy efficiency of GaN-based monolithic complementary logic circuits for integrated power conversion systems

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Fundamental Research 2021年第6期1卷 661-671页

作者： Zheyang Zheng Han Xu Li Zhang Kevin j.Chen Department of electronic and Computer engineering The Hong Kong University of Science and TechnologyClear Water BayKowloonHong Kong SARChina

Gallium nitride(GaN)-based power conversion systems exhibit striking competitiveness in realizing compact and high-efficiency power management *** emerging GaN-based p-channel field-effect transistors(FeTs)and monolithic integration techniques enable the implementation of GaN-based complementary logic(CL)circuits and thereby offer an additional pathway to improving the system-level energy efficiency and *** this article,holistic analyses are conducted to evaluate the potential benefits of introducing GaN CL circuits into the integrated power systems,based on the material limit of GaN and state-of-the-art experimental *** is revealed that the propagation delay of a single-stage CL gate based on the commercial p-GaN gate power HeMT(high-electron-mobility transistor)platform could be as short as sub-nanosecond,which sufficiently satis-fies the requirement of power conversion systems typically with operating frequencies less than 10 *** the currently adopted n-FeT-based logic gates(e.g.,directly coupled FeT logic)replaced by CL gates,the power consumption of peripheral logic circuits could be substantially suppressed by more than 10^(3) times,mainly due to the elimination of the pronounced static power ***,the energy efficiency of the entire system could be substantially improved.

关键词： Gallium nitride Complementary logic circuits Power integration energy efficiency

Structure-guided Capacitance Relationships in Oxidized Graphene Porous Materials Based Supercapacitors

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energy & environmental Materials 2023年第4期6卷 58-69页

作者： Srinivas Gadipelli Hanieh Akbari juntao Li Christopher A.Howard Hong Zhang Paul R.Shearing Dan j.L.Brett College of Physics Sichuan UniversityChengdu 610064China electrochemical Innovation Lab Department of Chemical EngineeringUniversity College LondonLondonWC1E 7JEUK Department of Physics and Astronomy University College LondonLondonWC1E 6BTUK

Supercapacitors formed from porous carbon and graphene-oxide(GO)materials are usually dominated by either electric double-layer capacitance,pseudo-capacitance,or *** to these combined features,reduced GO materials have been shown to offer superior capacitance over typical nanoporous carbon materials;however,there is a significant variation in reported values,ranging between 25 and 350 F g^(−1).This undermines the structure(e.g.,oxygen functionality and/or surface area)-performance relationships for optimization of cost and scalable *** work demonstrates important structure-controlled charge storage *** this,a series of exfoliated graphene(eG)derivatives are produced via thermal-shock exfoliation of GO precursors and following controlled graphitization of eG(GeG)generates materials with varied amounts of porosity,redox-active oxygen groups and graphitic *** results show significantly varied capacitance values between 30 and 250 F g^(−1)at 1.0 A g^(−1)in GeG structures;this suggests that for a given specific surface area the redox-active and hydrophilic oxygen content can boost the capacitance to 250–300%higher compared to typical mesoporous carbon *** with identical oxygen functionality show a surface area governed *** allows to establish direct structure-performance relationships between 1)redox-active oxygen functional concentration and capacitance and 2)surface area and capacitance.

关键词： electric double-layer capacitance graphene-oxide pseudocapacitance structure-performance relationships supercapacitors

亚洲古近纪早期的年代学和哺乳动物群更替(英文)

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古脊椎动物学报 2011年第1期49卷 1-28页

作者：丁素因童永生 William C.CLYDe Paul L.KOCH 孟津王元青 Gabriel j.BOWeN 李茜 Kathryn e.SNeLL 美国路易斯安那州立大学自然科学博物馆巴吞鲁日LA70803 中国科学院古脊椎动物与古人类研究所北京100044 美国新罕布什尔大学达拉莫NH03824 美国加州大学圣克鲁斯分校圣克鲁斯CA95064 美国自然历史博物馆纽约NY10024 美国普渡大学西拉斐特IN47907

对广东南雄盆地、江西池江盆地、安徽潜山盆地、湖南衡阳盆地和内蒙古二连盆地古新世和早始新世沉积物进行的生物地层学、化学地层学和磁性地层学研究,第一次给亚洲早古近纪地层框架提供了严格的年代限定。亚洲古新世和早始新世地层划分... 详细信息

对广东南雄盆地、江西池江盆地、安徽潜山盆地、湖南衡阳盆地和内蒙古二连盆地古新世和早始新世沉积物进行的生物地层学、化学地层学和磁性地层学研究,第一次给亚洲早古近纪地层框架提供了严格的年代限定。亚洲古新世和早始新世地层划分为4个生物年代单位(陆生哺乳动物期),从老到新为上湖期、浓山期、格沙头期和伯姆巴期4个亚洲陆生哺乳动物期。南雄盆地古地磁数据显示上湖期的底界约位于C29r的上2/3位置。南雄盆地的古地磁资料及池江盆地最新的古地磁和同位素结果显示上湖-浓山期界线在C27n的上部和C26r的下部之间,接近C27n-C26r转换界面。这一记录支持将上湖-浓山期的界线与北美陆生哺乳动物期中的Torrejonian-Tiffanian期以及海相记录中丹尼-塞兰特期(Danian-Selandi-an)的界线相对比。二连盆地古地磁和同位素研究表明典型的格沙头动物群延续至C24r,并且可能向下延伸至C25r和C26n。南雄盆地的记录指示浓山组和古城村组可能相当于C26r的上部。这些结果表明亚洲哺乳动物分期中的浓山-格沙头期的界线可能在北美哺乳动物分期的Tiffanian期中。衡阳盆地的古地磁和同位素证据指示,以短暂的碳同位素漂移为标志的古新世-始新世界线出现在栗木坪组和岭茶组之间,位于C24r中,与海相记录中的坦尼特-伊普里斯期(Thanetian-Ypresian)界线一致。伯姆巴期岭茶动物群的时代似乎与北美Wa-satchian-0带的动物群可以比较。上湖期和浓山期动物群主要由亚洲特有的动物组成。发生在上湖期和浓山期界线处的动物群更替,与北美Torrejonian-Tiffanian期界线以及丹尼-塞兰特期界线一致。在相隔很远的生态系统上的这种巧合,可能反映出各自独立的对气候变化的生态和/或进化上的响应。格沙头动物群的地方性色彩更弱,有与北美Clarkforkian期动物群共有的属一级分类单元。伯姆巴动物群是全球性的。现生哺乳动物各目在格沙头-伯姆巴期界线处突然出现,与北美和欧洲的记录一致,显示动物群的更替与古新世-始新世界线处短暂出现的全球变暖事件(又称古新世-始新世高温事件)有关。

关键词：亚洲古新世早始新世年代学

A Tool Path Re-generation Algorithm for Die & Mold Machining

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厦门大学学报（自然科学版） 2002年第S1期41卷 101-102页

作者： L P Zhang j Y H Fuh A Y C Nee Department of Mechanical engineering National University of SingaporeDepartment of Mechanical Engineering National University of SingaporeDepartment of Mechanical Engineering National University of Singapore SingaporeSingaporeSingapore

Facing the challenges of a shorter product design a nd manufacturing lead-time, many mold companies are using 3-D CAD/CAM software s ystems in design and manufacturing. A new product file is often issued to the mo ld design department before it is completely finalized and the design may have t o be iterated many times during the mold design and making processes. In practic e, if a mold has been modified, all the tool paths that cover the modified regio n must be re-generated, no matter how small the modified region may be. With th e available tool path generation systems, if a tool path needs to be re-generat ed, all the cutter location (CL) points must be re-calculated, and none of the original CL points can be re-used. It would require as much time to re-gen erate the modified tool path as in the original case. On the other hand, the mod ified region is usually quite small compared with the entire mold. The complete re-generation process is therefore highly unproductive and time-consuming. This paper proposes an efficient tool path re-generation approach for 3-axis d ie and mold machining. It is assumed in this research that a gouge-free too l path has been generated for the original mold and the same ball end-mill is to be used to generate the tool path for the modified mold. It is shown in th is work that if the boundary of the modified region is interference-free, the a ffected CL points are enclosed by a set of CL points which correspond to the poi nts on the boundary of the modified region. An efficient tool path re-generatio n algorithm was developed in this research. With this algorithm, a closed CL cur ve is first generated from the boundary of the affected region. The CL points fo r the original mold are then analyzed by comparing the x and y values with the b oundary of the affected CL points. If the CL points are not affected by the modi fication, they are output to the new CL file directly. Otherwise, they are remov ed and replaced by the new CL points

关键词： A Tool Path Re-generation Algorithm for Die Mold Machining

长期饮用不同浓度水氟人群外周血淋巴细胞SCe频率分析

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卫生研究 1996年第1期25卷 25-28页

作者：梁超轲吴云鹏马凤鲁慧 Y.Li B.P.Katz e.j.Brizendine G.K.Stookey 中国预防医学科学院环境卫生与卫生工程研究所北京100050 美国印第安纳大学牙科医院美国印第安纳大学医学院

报道了在正常营养与营养不足状态下,长期接触不同浓度水氟的人群外周血淋巴细胞姊妹染色单体交换(SCe)频率,以评价氟对人群的遗传毒性危险度。调查的人群组分为:0.2、1.0和4.8mg/L三个不同的饮水氟水平,每一组水氟浓度又分为正常营养与... 详细信息

报道了在正常营养与营养不足状态下,长期接触不同浓度水氟的人群外周血淋巴细胞姊妹染色单体交换(SCe)频率,以评价氟对人群的遗传毒性危险度。调查的人群组分为:0.2、1.0和4.8mg/L三个不同的饮水氟水平,每一组水氟浓度又分为正常营养与营养不足两组,共6个组。这些农民长期居住于该地区并饮用该氟浓度的水,年龄为40岁以上。结果表明,高浓度水氟未引起人群SCe频率增加,即本研究未发现氟的遗传毒性作用。

关键词：饮用水氟浓度遗传毒性淋巴细胞

胸部平片评分单独或联合其他风险评分预测COVID-19预后

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国际医学放射学杂志 2022年第2期 237-238页

作者： I.Au-Yong Y.Higashi e.Giannotti A.Fogarty j.R.Morling M.Grainge 朱珍

摘要放射学所显示的严重程度可能有助于预测新型冠状病毒肺炎（COVID-19）病人的病情恶化和结局。目的评估3种胸部平片报告系统[肺水肿（RALe）、Brixia和阴影百分比

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effect of an educational intervention and parental vaccine refusal forms on childhood vaccination rates in a clinic with a large Somali population

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Family Medicine and Community Health 2017年第3期5卷 188-192页

作者： Diane j.Madlon-Kay emily R.Smith University of Minnesota Medical Center Family Medicine Residency Program 2020 E.28th StreetMinneapolisMN 55407USA North Memorial Family Medicine Residency Program 1020 W Broadway AveMinneapolisMN 55411USA

Objective:The purpose of this study is to improve vaccination rates at a clinic with a large Somali population,and many vaccine hesitant *** study evaluated the effectiveness of some new materials for vaccine hesitant ***:educational sessions were given to providers and staff to give“talking points”and to introduce a vaccine refusal *** reviews were done for notes from 50 random well child visits per month of children less than six years old for 7 months before and after the ***:Before the intervention,44% of Somali children who needed shots did not get them at their well child ***,34% of the Somali children did not get their needed *** non-Somali children,16.8% did not get needed shots before the intervention,and 12.7% did not get needed shots after the intervention(P=0.07).The MMR was the most frequent vaccine *** the intervention,29 parents signed the vaccine refusal ***:The“talking points”and vaccine refusal form were associated with improve-ments in immunization rates in this challenging patient population that were not statistically *** form use was not well documented,so its true value requires further study.

关键词： Vaccination immunization MMR Somali