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Early response of understory vegetation to the mass dieback of Norway spruce in the European lowland temperate forest

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Forest Ecosystems 2024年第2期11卷 214-225页

作者： jan Marek Matuszkiewicz Andrzej N.Affek Piotr Zaniewski Ewa kołaczkowska Faculty of Geography and Regional Studies University of WarsawPoland Institute of Geography and Spatial Organization Polish Academy of SciencesPoland Institute of Forest Sciences Warsaw University of Life SciencesPoland

Spruce-dominated forests are commonly exposed to disturbances associated with mass occurrences of bark *** dieback of trees triggers many physical and chemical processes in the ecosystem resulting in rapid changes in the vegetation of the lower forest *** aimed to determine the response of non-tree understory vegetation to the mass dieback of Norway spruce(Picea abies)in the first years after the disturbance caused by the European spruce bark beetle(Ips typographus)*** study area was the Białowieża Biosphere Reserve covering the Polish part of the emblematic Białowieża Forest,in total 597km^(2).The main data source comprised 3,900 phytosociological relevés(combined spring and summer campaigns)collected from 1,300 systematically distributed forest sites in 2016–2018–the peak years of the bark beetle *** found that the understory responded immediately to mass spruce dieback,with the most pronounced changes observed in the year of the disturbance and the subsequent ***-tolerant forest species declined in the initial years following the mass spruce dieback,while hemicryptophytes,therophytes,light-demanding species associated with non-forest seminatural communities,as well as water-demanding forest species,*** acetosella,the most common understory species in the Białowieża Forest,showed a distinct fluctuation pattern,with strong short-term expansion right after spruce dieback,followed by a gradual decline over the next 3–4 years to a cover level 5 percentage points lower than before the ***,our study revealed that mass spruce dieback selectively affects individual herb species,and their responses can be directional and non-directional(fluctuation).Furthermore,we demonstrated that the mass dieback of spruce temporarily increases plant species diversity(α-diversity).

关键词： Forest disturbance Bark beetle outbreak Picea abies Ips typographus Response of understory vegetation Herbaceous species Biaowieza Forest

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Invasion of Artificial Vascular Graft into Duodenal Bulb after Living Donor Liver Transplantation

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Surgical Science 2015年第2期6卷 71-74页

作者： Yu-Ju Hung Kuo-Hua Lin Chen-Te Chou chih-jan ko Ping-Yi Lin Chia-En Hsieh Hsu-Heng Yen Yao-Li Chen Department of Surgery Changhua Christian Hospital Changhua Chinese Taipei Department of Medical Imaging Changhua Christian Hospital Changhua Chinese Taipei Transplant Medicine & Surgery Research Centre Changhua Christian Hospital Changhua Chinese Taipei Department of Gastroenterology Changhua Christian Hospital Changhua Chinese Taipei

Artificial vessel grafts are used for outflow reconstruction in living donor liver transplantation (LDLT). We report a very rare case of invasion of an artificial vascular graft into the duodenal bulb after LDLT. A 54-year-old man underwent LDLT in August 2012. A right hemiliver without a middle hepatic vein was used as a graft. The outflow of segment V was created by anatomizing an artificial graft to the inferior vena cava. During outpatient follow-up, the patient complained of acid regurgitation but did not experience abdominal pain. Panendoscopy was arranged and it revealed that the artificial graft had invaded the duodenal bulb. Operation was performed to remove the graft and the patient discharged after fourteen days of hospital stay. Invasion of artificial vascular grafts to adjacent organs is rare, but happens in living donor liver transplantation. It may be caused by inappropriate vessel graft length and adhesion between the graft and adjacent organs.

关键词： Living Donorliver Transplantation Artificialgraft

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Lewis blood genotypes of peptic ulcer and gastric cancer patients in Taiwan

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World Journal of Gastroenterology 2005年第31期11卷 4891-4894页

作者： Chi-Jung Yei jan-Gowth Chang Mu-Chin Shih Sheng-Fung Lin Chao-Sung Chang Fu-Tsong ko Kuang-Yang Lin Ta-chih Liu Blood Bandk Kaohsiung Medical University HospitalKaohsiung Taiwan China Depamnent of Laboratory Medicine China Medical University and Hospital Taichung Taiwan China Division of Hematology/Oncology Department of Internal Medicine Kaohsiung Medical University Hospital Kaohsiung Taiwan China Department of Internal Medicine Taipei Municipal Jen-Ai Hospital Taipei Taiwan China

AIM： The Lewis b （Le^b） antigen has been implicated as a possible binding site for attachment of Helicobacter pylori （H pylon） to gastric mucosa. However, studies both supporting and denying this association have been reported in the literature. Differences in secretor （Se） genotype have been suggested as a possible reason for previous discrepancies. Therefore, we investigated the relationship between Le and Se genotypes and Hpylori infection rates in people with peptic ulcer or gastric cancer. METHODS： Peripheral blood samples were obtained from 347 patients with endoscopic evidence of peptic ulcer disease （235 cases of duodenal ulcer, 62 of gastric ulcer, and 50 of combined duodenal ulcer/gastric ulcer） and 51 patients with gastric cancer on endoscopy. Peripheral blood specimens from 101 unrelated normal volunteers were used as controls. Lewis phenotype was determined using an antibody method, whereas Le and Se genotypes were determined by DNA amplification and restriction enzyme analysis. Gastric or duodenal biopsies taken from patients with endoscopic evidence of peptic ulcer or gastric cancer were cultured for Hpylotri Isolates were identified as Hpylori by morphology and production of urease and catalase. The Hpyloriinfection status was also evaluated by rapid urease test （CLO test）, and urea breath test （13^C-UBT）. Results of studies were analyzed by chi-square test （taken as significant）. RESULTS： Hpyloriwas isolated from 83.7% （303/347） of patients with peptic ulcer disease. Statistical analysis did not show any significant difference in Lewis phenotype or genotype between patients with and without Hpylori infection. No significant association was found between Lewis genotype and peptic ulcer or gastric ***： Lewis blood genotype or phenotype may not play a role in the pathogenesis of Hpyloriinfection. However, bacterial strain differences and the presence of more than one attachment mechanism may limit the value of epidemiological studies in e

关键词： Lewis histoblood group Helicobacter pylorr Peptic ulcer Gastric cancer

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Electrochemical Mechanism of Al Metal–Organic Battery Based on Phenanthrenequinone

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Energy Material Advances 2021年第1期2021卷 15-23页

作者： jan Bitenc Urban košir Alen Vizintin Niklas Lindahl AndražKrajnc Klemen Pirnat Ivan Jerman Robert Dominko Department of Materials Chemistry National Institute of ChemistryHajdrihova 191000 LjubljanaSlovenia Faculty of Chemistry and Chemical Technology University of LjubljanaVečna Pot 1131000 LjubljanaSlovenia Department of Physics University of GothenburgGöteborg SE-41296Sweden Department of Inorganic Chemistry and Technology National Institute of ChemistryHajdrihova 191000 LjubljanaSlovenia Alistore-European Research Institute CNRS FR 3104Hub de l’EnergieRue Baudelocque 80039 AmiensFrance

Al metal-organic batteries are a perspective high-energy battery technology based on abundant ***,the practical energy density of Al metal-organic batteries is strongly dependent on its electrochemical *** density is mostly governed by the nature of the aluminium complex ion and utilization of redox activity of the organic *** organic cathodes have been used before,detailed study of the electrochemical mechanism is typically not the primary *** the present work,electrochemical mechanism of Al metal-phenanthrenequinone battery is investigated with a range of different analytical ***,its capacity retention is optimized through the preparation of insoluble cross-coupled polymer,which exemplifies extremely low capacity fade and long-term cycling *** situ and operando ATR-IR confirm that reduction of phenanthrenequinone group proceeds through the two-electron reduction of carbonyl groups,which was previously believed to exchange only one-electron,severely limiting cathode *** of aluminium complex ion interacting with organic cathode is determined through multiprong approach using SEM-EDS,XPS,and solid-state NMR,which all point to the dominant contribution of AlCl2+*** full capacity utilization,Al metal-polyphenanthrenequinone battery utilizing AlCl2+offers an energy density of more than 200Wh/kg making it a viable solution for stationary electrical energy storage.

关键词： battery Battery utilizing

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Association between hepatitis B and metabolic syndrome:Current state of the art

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World Journal of Gastroenterology 2016年第1期22卷 155-164页

作者： Peter Jarcuska Sylvia Drazilova jan Fedacko Daniel Pella Martin janicko 1st Department of Internal Medicine University Hospital and Pavol Jozef Šafárik University in Kosice04001 KošiceSlovakia Department of Internal Medicine Hospital Poprad A.S.05845 PopradSlovakia

Chronic hepatitis B(CHB)is a global health issue that increases the risk of liver cirrhosis and hepatocellular carcinoma in infected *** syndrome(Met S)is a disease endemic mostly to the developed *** is associated with high cardiovascular mortality and morbidity,diabetes mellitus as well as *** this manuscript,we systematically review the published data on the relationship between Met S and CHB *** studies have described highly variable correlations between CHB on one hand and Met S,non-alcoholic fatty liver disease and dyslipidemia on the *** association between CHB and diabetes mellitus or atherosclerosis has been described as of *** presence of Met S in patients infected with hepatitis B virus increases the risk of fibrosis,cirrhosis and hepatocellular *** lifestyle,but also pharmacological interventions are needed to prevent the development of these complications.

关键词： Hepatitis B Nonalcoholic fatty liver disease Fibrosis Cirrhosis Metabolic syndrome Hepatocellularcarcinoma

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Accurate surface normal representation to facilitate gradient coil optimization on curved surface

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Magnetic Resonance Letters 2023年第1期3卷 67-84,I0004页

作者： Hao Ren Hui Pan Feng Jia jan G.korvink Zhenyu Liu Changchun Institute of Optics Fine Mechanics and PhysicsChinese Academy of SciencesChangchun130033China School of Optoelectronics University of Chinese Academy of SciencesBeijing101499China Department of Radiology Medical PhysicsMedical Center University of FreiburgFaculty of MedicineUniversity of FreiburgFreiburg79110Germany Institute of Microstructure Technology Karlsruhe Institute of Technology(KIT)Karlsruhe76049Germany

The design methods for gradient coils are mostly based on discrete extrinsic methods(e.g.,the BioteSavart integration calculation),for which the surface normal vector strongly influences any numerical calculation of the discretized *** studies are mostly based on regular or analytical surfaces,which allow normal vectors to be expressed *** certain applications,design methods for extending currentcarrying surfaces from developable or analytic geometries to arbitrary surfaces generated from a scanned point cloud are *** key task is to correctly express the discretized normal vectors to ensure geometrical accuracy of the designed ***,it has been proven that applying a Delaunay triangulation to approximate a smooth surface can result in the discrete elemental normal vectors converging to those of the original ***,this article uses Delaunay triangulation to expand upon previous design methods so that they encompass arbitrary piecewise continuous *** design methods,the stream function and the so-called solid isotropic material with penalization(SIMP)method,are used to design circumvolute and noncircumvolute gradient coils on general surfaces.

关键词： Gradient coils Delaunay triangulation Stream function SIMP method

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基于神经网络的损伤构件及损伤程度识别

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工程力学 2006年第2期23卷 18-22页

作者：孙宗光高赞明倪一清大连海事大学大连116026 香港理工大学香港

确定损伤构件及其损伤程度是分阶段损伤识别的最后一步,同时又是进一步制定结构安全运行决策的前提和基础。研究了在确定了结构损伤区域的条件下,应用反向传播(BP)神经网络同时实现对具体损伤构件及其损伤程度识别的方法。探讨了针对上... 详细信息

确定损伤构件及其损伤程度是分阶段损伤识别的最后一步,同时又是进一步制定结构安全运行决策的前提和基础。研究了在确定了结构损伤区域的条件下,应用反向传播(BP)神经网络同时实现对具体损伤构件及其损伤程度识别的方法。探讨了针对上述神经网络训练数据的构造和训练策略。应用提出的方法对汲水门斜拉桥桥面结构进行了损伤识别仿真模拟。基于模态参数对损伤的灵敏度分析,选取了12个自振频率和损伤区域附近的6个振型分量作为构造网络输入的基本数据。网络的输出向量同时指示了损伤构件及其损伤程度。就模拟的10种损伤情况,当损伤程度达到60%以上时,有9种实现了正确的构件识别,半数以上给出了可以接受的损伤程度描述。

关键词：损伤检测损伤构件识别损伤程度识别神经网络斜拉桥

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Different micro/nano-scale patterns of surface materials influence osteoclastogenesis and actin structure

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Nano Research 2022年第5期15卷 4201-4211页

作者： Tsukasa Akasaka Miho Tamai Yoshitaka Yoshimura Natsumi Ushijima Shinichiro Numamoto Atsuro Yokoyama Hirofumi Miyaji Ryo Takata Shuichi Yamagata Yoshiaki Sato ko Nakanishi Yasuhiro Yoshida Department of Biomaterials and Bioengineering Faculty of Dental MedicineHokkaido UniversitySapporo 060-8586Japan Immune Signal Unit Okinawa Institute of Science and Technology Graduate UniversityOkinawa 904-0495Japan Department of Pharmacology Faculty of Dental Medicine and Graduate School of Dental MedicineHokkaido UniversitySapporo 060-8586Japan Support Section for Education and Research Faculty of Dental MedicineHokkaido UniversitySapporo 060-8586Japan Oral Functional Prosthodontics Division of Oral Functional ScienceFaculty of Dental MedicineHokkaido UniversitySapporo 060-8586Japan Department of Periodontology and Endodontology Faculty of Dental MedicineHokkaido UniversitySapporo 060-8586Japan Department of Orthodontics Faculty of Dental Medicine and Graduate School of Dental MedicineHokkaido UniversitySapporo 060-8586Japan

The surface topography of a material can influence osteoclast ***,the surface structural factors that promote osteoclast activity have not yet been investigated in ***,we investigated osteoclastogenesis by testing various defined patterns with different dimensions and *** systematic patterns,made of a cyclo-olefin polymer,were prepared at a micron-,submicron-,and nano-scale with a groove,hole,or pillar shape with a 1:1 pitch ***264.7 cells were cultured on these patterns in the presence of the receptor activator of NF-κB ligand(RANKL).Osteoclast formation was induced in the order:pillar>groove≥*** two-dimensional factors also indicated that submicron-sized patterns strongly induced osteoclast *** optimal pillar dimension for osteoclast formation was 500 nm in diameter and 2μm in ***,we observed two types of characteristic actin structure,i.e.,belt-like structures with small hollow circles and isolated ring-like structures,which formed on or around the pillars depending on size and ***,resorption pits were observed mainly on the top of calcium phosphate-coated ***,osteoclasts prefer convex shapes,such as pillars for differentiation and *** results indicate that osteoclastogenesis can be controlled by designing surfaces with specific morphologies.

关键词： micro/nano-pattern pillar RAW264.7 osteoclast actin structure resorption pit

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多自由度参激系统稳定性的数值分析

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计算力学学报 2007年第5期24卷 678-682页

作者：应祖光陈昭晖倪一清高赞明浙江大学力学系浙江杭州310027 香港理工大学土木及结构工程系

提出多自由度周期参激系统稳定性的数值直接法。通过将扰动方程表示成状态方程形式,再根据Flo-quet理论将扰动解表示成指数特征分量与周期分量之积,并将其周期分量与系统周期系数展成Fourier级数,导出一系列代数方程,建立矩阵特征值问题... 详细信息

提出多自由度周期参激系统稳定性的数值直接法。通过将扰动方程表示成状态方程形式,再根据Flo-quet理论将扰动解表示成指数特征分量与周期分量之积,并将其周期分量与系统周期系数展成Fourier级数,导出一系列代数方程,建立矩阵特征值问题,从而由数值求解特征值可直接确定参激系统的稳定性。该方法可用于一般周期参激阻尼系统,特征值矩阵不含逆子阵。应用于斜拉索在支座周期运动激励下的参激振动不稳定性分析,数值结果表明该方法的有效性。

关键词：参激稳定性多自由度系统数值直接法特征值

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斜拉索张力测试和参数评估的理论和应用

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土木工程学报 2005年第3期38卷 64-69页

作者：郑罡倪一清高赞明徐兴重庆交通科研设计院香港理工大学浙江大学

基于较完善的有限元模型,通过最小化频率测量值与计算值间的误差,建立了利用多阶测试频率识别斜拉索张力、长度、抗弯刚度、线密度以及支撑条件等多个参数的基本理论,极大地提高了斜拉索张力测试的准确度和可靠度。作为实例,对洞庭湖大... 详细信息

基于较完善的有限元模型,通过最小化频率测量值与计算值间的误差,建立了利用多阶测试频率识别斜拉索张力、长度、抗弯刚度、线密度以及支撑条件等多个参数的基本理论,极大地提高了斜拉索张力测试的准确度和可靠度。作为实例,对洞庭湖大桥的斜拉索进行了张力测试和参数评估。

关键词：斜拉索张力测试参数评估动力测试

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