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Colonic perforation in Behet's syndrome

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World journal of Gastroenterology 2008年第42期14卷 6578-6580页

作者： Catherine M Dowling Arnold DK Hill Carmel Malone john j Sheehan Shona Tormey Kieran Sheahan Enda McDermott Niall j O’higgins Department of Surgery St. Vincents University Hospital Elm Park Dublin 4 Ireland Department of Radiology St. Vincent's University Hospital Elm Park Dublin 4 Ireland Department of Pathology St. Vincent's University Hospital Elm Park Dublin 4 Ireland

A 17-year-old gentleman was admitted to our hospital for headache, the differential diagnosis of which included Behcet＇s syndrome （BS）. He developed an acute abdomen and was found to have air under the diaphragm on erect chest X-ray. Subsequent laparotomy revealed multiple perforations throughout the colon. This report describes an unusual complication of Behcets syndrome occurring at the time of presentation and a review of the current literature of reported cases.

关键词： Colonic perforation Behcet's syndrome

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内爆驱动式超高速发射技术的初步研究

高压物理学报 2020年第3期34卷 56-63页

作者：王马法 higgins Andrew j 焦德志黄洁柳森中国空气动力研究与发展中心四川绵阳621000 麦吉尔大学工程力学系魁北克蒙特利尔H3A2K6加拿大

为获得10 km/s左右的超高速发射能力,以内爆发射器为研究对象,利用AUTODYN 2D软件对口径为8 mm的内爆发射器进行有限元仿真分析,获得了典型状态下的弹丸发射速度。研制了口径为8 mm的内爆发射器,并在压缩管中填充5 MPa氦气进行实验,分... 详细信息

为获得10 km/s左右的超高速发射能力,以内爆发射器为研究对象,利用AUTODYN 2D软件对口径为8 mm的内爆发射器进行有限元仿真分析,获得了典型状态下的弹丸发射速度。研制了口径为8 mm的内爆发射器,并在压缩管中填充5 MPa氦气进行实验,分别获得了0.55 g铝合金弹丸7.95 km/s和0.37 g镁合金弹丸10.28 km/s的发射速度,与有限元仿真计算结果的速度偏差分别为15.3%和3.7%。结果表明,设计的内爆发射器具备10 km/s发射能力,满足空间碎片撞击和防护研究的超高速发射需求。

关键词：发射技术超高速内爆驱动式

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Comprehensive study of a versatile polyol synthesis approach for cathode materials for Li-ion batteries

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Nano Research 2019年第9期12卷 2238-2249页

作者： Hyeseung Chung Antonin Grenier Ricky Huang Xuefeng Wang Zachary Lebens-higgins jean-Marie Doux Shawn Sallis Chengyu Song Peter Ercius Karena Chapman Louis F.j.Piper Hyung-Man Cho Minghao Zhang Ying Shirley Meng Department of NanoEngineering University of CaliforniaSan DiegoLa JollaCA 92093USA Chemistry Department Stony Brook UniversityStony BrookNY 11794USA Department of Physics Applied Physics and AstronomyBinghamton UniversityBinghamtonNY 13902USA Advanced Light Source Lawrence Berkeley National Laboratory1 Cyclotron RoadBerkeleyCA 94720USA National Center for Electron Microscopy Molecular FoundryLawrence Berkeley National LaboratoryBerkeleyCA 94720USA

This work reports a comprehensive study of a novel polyol method that can successfully synthesize layered LiNi0.4Mn0.4Co0.2O2,spinel LiNi0.5Mn1.5O4,and olivine LiCoPO4 cathode *** properly designed,polyol method offers many advantages such as low cost,ease of use,and proven scalability for industrial *** importantly,the unique properties of polyol solvent allow for greater morphology control as shown by all the resulting materials exhibiting monodispersed nanoparticles *** morphology contributes to improved lithium ion transport due to short diffusion ***-synthesized LiNi0.4Mn0.4Co0.2O2 delivers a reversible capacity of 101 and 82 mAh.g-1 using high current rate of 5C and 10C,*** also displays surprisingly high surface structure stability after chargedischarge *** step of the reaction was investigated to understand the underlying polyol synthesis mechanism.A combination of in situ and ex situ studies reveal the structural and chemical transformation of Ni-Co alloy nanocrystals overwrapped by a Mn-and Li-embedded organic matrix to a sedes of intermediate phases,and then eventually to the desired layered oxide phase with a homogeneous distribution of Ni,Co,and *** envisage that this type of analysis will promote the development of optimized synthesis protocols by establishing links between experimental factors and important structural and chemical properties of the desired *** insights can open a new direction of research to synthesize high-performance intercalation compounds by allowing unprecedented control of intermediate phases using experimental parameters.

关键词： polyol cathode synthesis nanoparticle LiNi0.4Mn0.4Co0.2O2(NMC)

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黑鹰行动

黑鹰行动

作者： j.·希金斯(j. higgins)

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GaAs功率FET互调失真的分析和改进

微纳电子技术 1981年第5期 30-41页

作者： j.A.higgins 学工

为了降低GaAs功率FET的互调失真(IMD),掺杂分布的修正是一种有效的手段。对外延工艺来说,要可重复地、并且均匀性良好地制备所要求的杂质分布是一项困难的任务。这种缺陷已促使人们研究用离子注入的方法来制造高级的线性功率 FET。为了... 详细信息

为了降低GaAs功率FET的互调失真(IMD),掺杂分布的修正是一种有效的手段。对外延工艺来说,要可重复地、并且均匀性良好地制备所要求的杂质分布是一项困难的任务。这种缺陷已促使人们研究用离子注入的方法来制造高级的线性功率 FET。为了探索有源层掺杂分布与互调失真之间的关系,提出了一个解析的器件模型。这些计算揭示了失真电平变化的复杂性质,这种变化是由非线性跨导和输出电导相互之间的一部分关系产生的。用器件模型来鉴定注入的剂量和能量,以便实现最佳的有源层杂质分布。根据这些结果,在器件制造中先做一次深的硒注入而后用浅的铍注入来补偿表面层的掺杂浓度。晶体管的互调失真是用双音方法测量的。为了进行比较,还估测了具有平的掺杂分布的常规外延 FET。这一比较表明:通过采用修正的注入分布,在监测点三级互调积可以提高4dB。实验表明:对离子注入的晶体管来说,最大输出功率和最小互调失真的调谐条件实质上是相同的,从而与具有平的掺杂分布的常规器件的特性形成了明显的对照。这些性能上的优点以及掺杂参量的高度的均匀性和重复性都表明离子注入是制造高级线性功率 FET 的一种有效的技术。

关键词：互调失真掺杂分布 FET 跨导有源层偏置条件杂质分布 GaAs

Investigation of imploding shock waves using the hydraulic analogy

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Investigation of imploding shock waves using the hydraulic a...

The 24th International Symposium on Shock Waves

作者： C.B.Kiyanda P.Chaput A.j.higgins j.H.S.Lee McGill University Montreal QC H3A 2K6 Canada

Imploding hydraulic jumps in water are created by reservoir-type (RT) and gate-type (GT) water tables. After comparison with the Chestner-Chisnell-Whitham (CCW) approximate solution of imploding hydraulic jumps, the critical range of operation where the dynamics of the imploding water waves are similar to imploding gaseous shock waves is identified. Possible details are identified that enable water waves in this critical range to behave analogously to gaseous shock waves.

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建设性的创造和革新──长期成功的保证

工程设计学报 1998年第1期5卷 1-4页

作者： j.M.higgins G.G.Wiese 黄靖远清华大学精仪系

为了在激烈的革新竞争中卓有成效地取得全球市场，企业必须有效地利用创造性这个“取之不尽的资源”。关键因素“相对差距”和“相对低成本”的符合形势要求的均衡对于必要的竞争优势来说起着决定性的作用。一个促进创造性的组织文化为... 详细信息

为了在激烈的革新竞争中卓有成效地取得全球市场，企业必须有效地利用创造性这个“取之不尽的资源”。关键因素“相对差距”和“相对低成本”的符合形势要求的均衡对于必要的竞争优势来说起着决定性的作用。一个促进创造性的组织文化为符合市场要求的革新准备了肥沃的土壤，从而导致长期性的成功。

关键词：产品开发产品革新企业创造性市场需求

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Nitrogen Dioxide and Ozone Pollution in the Chicago Metropolitan Area

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journal of Environmental Protection 2020年第8期11卷 551-569页

作者： Zixian Wang jennifer L. Anthony Larry E. Erickson Michael j. higgins Gregory L. Newmark Tim Taylor Department of Chemical Engineering Kansas State University Manhattan KS USA Department of Statistics Kansas State University Manhattan KS USA Department of Landscape Architecture/Regional and Community Planning Kansas State University Manhattan KS USA

Ground-level ozone is a harmful air pollutant associated with several health issues. Ozone concentrations have exceeded the National Ambient Air Quality Standards (NAAQS) in the Chicago metropolitan area on hot summer days for many years because of nitrogen oxide and volatile organic compound emissions. Annual fourth highest 8-hour ozone concentrations have been between 0.070 and 0.084 ppm at several monitoring sites in Cook county, during the 2016-2018 time period. The continuous measurement of nitrogen dioxide (NO2) and ozone (O3) was conducted in several communities in Chicago in 2017. The air pollution impacts the health of all who live in the area. The data were used to analyze correlations between the O3 distribution and its association with ambient concentrations of NO2 from transportation emissions. Higher concentrations in NO2 and O3 occurred in succession in the daytime. The diurnal variation of O3 concentration was analyzed. The daily cycle of NO2 concentration reaches a maximum in the late morning and has smaller nighttime concentrations. The daily cycle of ozone concentration reaches the maximum in the afternoon and also becomes smaller for nighttime concentrations. In addition, relationships were found between O3 and NO2. Monthly variations of ozone and NO2 are presented. Some options to reduce ozone pollution are presented.

关键词： Volatile Organic Compounds Health Vehicle Emissions Daily Transient Cycles Ozone Precursors Photochemical Reactions

Short Sleep Duration is Associated with Central Arterial Stiffness in Children Independent of Other Lifestyle Behaviors

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journal of Science in Sport and Exercise 2020年第3期2卷 236-245页

作者： Lee Stoner Simon higgins Katherine Black Kim Boggess Michelle L.Meyer Andrea Chou Barbara Galland jillian j.Haszard Kim Meredith-jones Pouya Saeedi Sheila Skeaff Paula M.L.Skidmore Department of Exercise and Sport Science University of North Carolina at Chapel HillChapel HillNCUSA Department of Exercise Science Elon UniversityElonNCUSA Department of Human Nutrition University of OtagoDunedinNew Zealand Division of Maternal-Fetal Medicine School of MedicineUniversity of North Carolina at Chapel HillChapel HillNCUSA Department of Emergency Medicine School of MedicineUniversity of North Carolina at Chapel HillChapel HillNCUSA Department of Women and Childrens Health University of OtagoDunedinNew Zealand Department of Medicine University of OtagoDunedinNew Zealand Department of Medicine University of OtagoChristchurchNew Zealand

Purpose Children require 9-11 h sleep to ensure adequate growth and development by optimizing the efficiency of a number of biological systems,including the cardiovascular *** study aim was to determine whether short sleep duration(justed]association between short sleep duration and cfPWV(β=0.245,95%CI 0.093-0.396).This association persisted following adjustment for demographic factors and was strengthened following adjustment for lifestyle behaviors(β=0.331,95%CI 0.109-0.553).Conclusions Short sleepers(<9 h)had a clinically meaningful elevated aortic arterial stiffness in comparison to those sleeping the recommended daily 9-11 *** duration may be important for cardiovascular health independent of other lifestyle behaviors.

关键词： Pulse wave velocity Cardiovascular disease Sedentary behaviour Physical activity Diet