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Rising utilization of stable isotopes in tree rings for climate change and forest ecology

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Journal of Forestry Research 2024年第1期35卷 103-116页

作者： Ru Huang Chenxi Xu Jussi Grießinger Xiaoyu Feng Haifeng Zhu Achim bräuning National Institute of Natural Hazards Beijing 100085People’s Republic of China Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029People’s Republic of China CAS Center for Excellence in Life and Paleoenvironment Beijing 100044People’s Republic of China Institute of Geography Friedrich-Alexander-University of Erlangen-Nuremberg91058 ErlangenGermany State Key Laboratory of Tibetan Plateau Earth System Environment and Resources(TPESER)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101People’s Republic of China University of Chinese Academy of Sciences Beijing 100049People’s Republic of China

Analyses of stable isotopes(C,O,H)in tree rings are increasingly important cross-disciplinary *** rapid development in this field documented in an increasing number of publications requires a comprehensive *** study includes a bibliometric analysis-based review to better understand research trends in tree ring stable isotope ***,1475 publications were selected from the Web of Science Core Collection for *** findings are that:(1)numbers of annual publications and citations increased since *** 1974 to 1980,there were around two relevant publications per ***,from 2020 to 2022,this rose sharply to 109 publications per ***,average article citations were less than four per year before 1990,but were around four per article per year after 2000;(2)the major subjects using tree ring stable isotopes include forestry,geosciences,and environmental sciences,contributing to 42.5%of the total during 1974-2023;(3)the top three most productive institutions are the Chinese Academy of Sciences(423),the Swiss Federal Institute for Forest,Snow and Landscape Research(227),and the University of Arizona(204).These achievements result from strong collaborations;(4)review papers,for example,(Dawson et al.,Annu Rev Ecol Syst 33:507-559,2002)and(McCarroll and Loader,Quat Sci Rev 23:771-801,2004),are among the most cited,with more than 1000 citations;(5)tree ring stable isotope studies mainly focus on climatology and ecology,with atmospheric CO_(2) one of the most popular *** 2010,precipitation and drought have received increasing *** on this analysis,the research stages,key findings,debated issues,limitations and direc-tions for future research are *** study serves as an important attempt to understand the progress on the use of stable isotopes in tree rings,providing scientific guid-ance for young researchers in this field.

关键词： Tree rings Stable isotopes Web of Science Bibliometric

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长寿命UHPfrC组合钢桥面板研究综述

交通运输工程学报 2024年第1期24卷 68-84页

作者：段兰袁翊竑王春生 brÜHWILER Eugen 长安大学公路学院陕西西安710064 瑞士洛桑联邦理工学院结构维护与安全实验室沃州洛桑CH-1015

从三方面归纳与剖析了超高性能纤维增强水泥基(UHPfrC)复合材料组合钢桥面板的研究进展,包括强韧性组合层选材、界面传力机制与损伤累积机理、设计方法与工程应用;总结了纤维类型、纤维掺量对UHPfrC轴拉性能和抗弯性能的影响规律,确定... 详细信息

从三方面归纳与剖析了超高性能纤维增强水泥基(UHPfrC)复合材料组合钢桥面板的研究进展,包括强韧性组合层选材、界面传力机制与损伤累积机理、设计方法与工程应用;总结了纤维类型、纤维掺量对UHPfrC轴拉性能和抗弯性能的影响规律,确定了支撑组合钢桥面板结构分析的多种本构模型;对比分析了热连接、冷连接和混合连接组合界面设计方式的技术特点,归纳了胶粘界面、冷连接剪力键界面与混合连接界面的传力机理试验与理论研究成果;总结了基于冷连接设计理念的组合钢桥面板在合理构造、设计方法、规范规程与工程实践等方面的研究成果,并探讨了长寿命组合钢桥面板的创新与发展方向。研究结果表明:单一或混杂纤维的掺入综合提升了UHPfrC的应变强化能力、弯曲变形能力、抗断裂能力、裂缝宽度控制能力和抗疲劳性能,轴拉条件下UHPfrC三线型简化本构模型有力支撑了组合钢桥面板的设计计算,弹塑性损伤本构模型可描述不可逆疲劳损伤累积;验证了冷连接组合界面的增韧效果与可靠性,新型剪力键既可以提高组合效应,也能增韧UHPfrC层,混合连接界面具有降低界面局部应力集中、提高整体界面抗剪刚度、改善界面传力、提升施工效率等综合技术优势,内聚界面本构模型可实现冷连接界面损伤累积反演分析,界面损伤预测结果准确可靠;基于冷连接的UHPfrC组合钢桥面板可以有效提高钢桥面板的局部刚度,相关设计方法可支撑标准的编制与工程实践;应进一步提升UHPfrC的性价比和界面连接的高效性和可靠性,以支撑组合钢桥面板的长寿命、强韧性、轻量化、易维护、低能耗设计与建造。

关键词：桥梁工程长寿命 UHPfrC组合钢桥面板冷连接件组合界面设计准则免蒸养

Stranched Internal Hernia Revealed by Occlusion of the Large Libra: A Propos of a Case

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Case Reports in Clinical Medicine 2024年第1期13卷 37-42页

作者： Abdoulaye Kanté Mamady Almami Kéita Idrissa Tounkara Drissa Ouattara bréhima Bengaly Souleymane Sanogo bréhima Togola Drissa Traoré Nouhoum Ongoiba General Surgery Department of The Kati-Mali Reference Health Center Koulikoro Mali Service of Surgery “B” of The CHU Du Point G Faculty of Medicine and Odontostomatology Bamako Mali

The left para-duodenal internal hernia, whose origin is generally embryological, is a rare etiology of intestinal obstruction found mainly in young adults. We report here the case of acute intestinal obstruction by left para-duodenal internal hernia in a 36-year-old young man. It was a patient who consulted urgently for occlusive syndrome with cessation of materials and gases. Abdominal percussion noted abdominal tympanism and pre-hepatic dullness was preserved. The flow and icicle signs were negative. Palpation did not objectify hepatosplenomegaly and did not find any organomegaly either. On the other hand, she found an epigastric defense. The abdominal X-ray without preparation showed water levels that were wider than high, hail-like. We performed a median above and below umbilical laparotomy and intraoperatively, it was an internal hernia with incarceration of small loops in a voluminous left paraduodenal sac of 12 cm. They were not necrotic and quickly recolored after extrication. We resected the hernial sac and closed the hernial orifice with separate stitches with absorbable suture 0. The postoperative course was simple. The patient was discharged from the hospital on the 4th postoperative day. After 18 months of hindsight, he is doing well.

关键词： Paraduodenal Internal Hernia Occlusion Laparotomy

Localized-states quantum confinement induced by roughness in CdMnTe/CdTe heterostructures grown on Si(111) substrates

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Journal of Semiconductors 2024年第9期45卷 28-35页

作者： Leonarde N.Rodrigues Wesley F.Inoch Marcos L.F.Gomes Odilon D.D.Couto Jr. bráulio S.Archanjo Sukarno O.Ferreira Physics Department Federal University of ViçosaViçosa36570-900Minas GeraisBrazil Instituto de Física Gleb Wataghin Universidade Estadual de CampinasCampinas13083-859São PauloBrazil National Institute of Metrology Quality and Technology(Inmetro) Materials Metrology Division(DIMAT)Xerém2525-020Rio de JaneiroBrazil

This work shows that despite a lattice mismatch of almost 20%, CdMnTe/CdTe/CdMnTe heterostructures grown directly on Si(111) have surprisingly good optical emission properties. The investigated structures were grown by molecular beam epitaxy and characterized by scanning transmission electron microscopy, macro-and micro-photoluminescence. Low temperature macro-photoluminescence experiments indicate three emission bands which depend on the CdTe layer thickness and have different confinement characteristics. Temperature measurements reveal that the lower energy emission band (at 1.48 eV)is associated to defects and bound exciton states, while the main emission at 1.61 eV has a weak 2D character and the higher energy one at 1.71 eV has a well-defined (zero-dimensional, 0D) 0D nature. Micro-photoluminescence measurements show the existence of sharp and strongly circularly polarized (up to 40%) emission lines which can be related to the presence of Mn in the heterostructure. This result opens the possibility of producing photon sources with the typical spin control of the diluted magnetic semiconductors using the low-cost silicon technology.

关键词： CdMnTe/CdTe/CdMnTe heterostructure CdTe/CdMnTe quantum emitters quantum dot-like emission silicon(111)substrate

Investigating the inflow into a granular bed using a locally resolved method

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Particuology 2024年第2期85卷 89-101页

作者： Maximilian brommer Maik Scharnowski Enric Illana Mahiques Siegmar Wirtz Viktor Scherer Ruhr University Bochum Institute of Energy Plant TechnologyUniversitätsstraβe 15044780BochumGermany

Discrete Element Method-Computational Fluid Dynamics(DEM/CFD)simulations of industrial-scale granular systems employ spatial averaging(porous media approach)for the fluid-particle interaction in the whole domain,which can lead to poor accuracy,for instance at flow inlets,as local particle bulk morphology is not *** paper presents an approach where the interstitial flow in crucial areas with large gradients can be resolved locally in an otherwise unresolved domain,so that a mixed resolved-unresolved method is *** a generic example to show the feasibility and performance of the new approach,the inflow of ambient air into a flat-bottom hopper through a narrow orifice is *** an experimental setup,the vertical profile of the pressure decay through the inlet and across the packing is chosen for com-parison with respective *** obtained with the conventional porous media method and the locally resolved approach are compared to these experiments for varying volume flow rates and for two different particle *** of different size as well as dodecahedrons are *** is found that although averaging methods already provide good approximations,the locally resolved method can improve the result especially when conventional drag laws are not applicable due to wall effects or if large velocity gradients exist.

关键词： DEM/CFD Packed bed Pressure drop

Imaging of the gastrointestinal tract-novel technologies

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World Journal of Gastroenterology 2009年第2期15卷 160-168页

作者： Jens brφndum frφkjr Asbjφrn Mohr Drewes Hans Gregersen Mech-Sence Aalborg HospitalDK-9000 Aalborg Denmark Department of Radiology Aalborg Hospital DK-9000 Aalborg Denmark Mech-Sence Aalborg Hospital DK-9000 Aalborg Denmark Mech-Sense Department of Medical Gastroenterology Aalborg University Hospital DK-9000 Aalborg Denmark National Center for Ultrasound in Gastroenterology Haukeland University Hospital Bergen Norway Center for Sensory-Motor Interaction (SMI) Department of Health Science and Technology Aalborg University Denmark Center for Sensory-Motor Interaction (SMI) Department of Health Science and Technology Aalborg University DK-9000 Aalborg Denmark

Imaging of the gastrointestinal tract is very useful for research and clinical studies of patients with symptoms arising from the gastrointestinal tract and in visualising anatomy and pathology. Traditional radiological techniques played a leading role in such studies for a long time. However, advances in non-invasive modalities including ultrasound (US), computed tomography (CT), positron emission tomography (PET), magnetic resonance imaging (MRI), etc, have in the last decades revolutionised the way in which the gastrointestinal tract is studied. The resolution of imaging data is constantly being improved and 3D acquisition, tools for fi ltering, enhancement, segmentation and tissue classif ication are continually being developed. Additional co-registration techniques allow multimodal data acquisition with improved classif ication of tissue pathology. Furthermore, new functional imaging techniques have become available. Altogether, the future of gastrointestinal imaging looks very promising which will be of great benef it in clinical and research studies of gastrointestinal diseases. The purpose of this review is to highlight the capabilities of the newest techniques to explore the detailed morphology, biomechanical properties, function and pathology of the gastrointestinal tract.

关键词： Computed tomography Gastrointestinaltract Imaging Magnetic resonance Radiology Ultrasound

Localized-states quantum confinement induced by roughness in CdMnTe/CdTe heterostructures grown on Si(111) substrates

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Journal of Semiconductors 2024年第9期 34-42页

作者： Leonarde do Nascimento Rodrigues Wesley Fiorio lnoch Marcos L.F.Gomes Odilon D.D.Couto Jr. bráulio S.Archanjo Sukarno Olavo Ferreira Physics Department Federal University of Vi?osa Instituto de Física Gleb Wataghin Universidade Estadual de Campinas National Institute of Metrology Quality and Technology (Inmetro) Materials Metrology Division (DIMAT)

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Upper gastrointestinal sensory-motor dysfunction in diabetes mellitus

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World Journal of Gastroenterology 2006年第18期12卷 2846-2857页

作者： Jingbo Zhao Jens brφndum frφkjaer Asbjφrn Mohr Drewes Niels Ejskjaer Center of Excellence in Visceral Biomechanics and Pain Aalborg Hospital Sφndre Skovvej 15 DK-9000 Aalborg Denmark & Center for Sensory-Motor Interactions Department of Health Science Aalborg University Fredrik Bajers Vej 7 D-3 DK-9220 Aalborg Denmark Department of Medicine M (Diabetes & Endocrinology) Aarhus University Hospital Norrebrogade 44 DK 8000 Aarhus C Denmark

Gastrointestinal （GI） sensory-motor abnormalities are common in patients with diabetes mellitus and may involve any part of the GI tract. Abnormalities are frequently sub-clinical, and fortunately only rarely do severe and life-threatening problems occur. The pathogenesis of abnormal upper GI sensory-motor function in diabetes is incompletely understood and is most likely multi-factorial of origin. Diabetic autonomic neuropathy as well as acute suboptimal control of diabetes has been shown to impair GI motor and sensory function. Morphological and biomechanical remodeling of the GI wall develops during the duration of diabetes, and may contribute to motor and sensory dysfunction. In this review sensory and motility disorders of the upper GI tract in diabetes is discussed; and the morphological changes and biomechanical remodeling related to the sensory-motor dysfunction is also addressed.

关键词： Diabetes Esophagus Stomach Intestine Motility Pain Diabetic neuropathy Hyperglycemia Remodeling

Digestive Surgical Emergencies at the “Mother Child”Hospital Center Luxembourg in Mali

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Surgical Science 2024年第5期15卷 299-310页

作者： Cheickna Tounkara Amara Coulibaly Yaya Ongoiba Aboubakrine Sylla Abdoul Karim Simaga bréhima B. Coulibaly Aminata Dabo Souleymane Dembele Samake Hamidou Sidiki Keita Sékou bréhima Koumare Soumaïla Keita Bakary Tientigui Dembele Zimogo Zié Sanogo Djibril Sangare Department of General Surgery and Anesthesia-Resuscitation of the “ Mother Child&#8221 Hospital Center Luxembourg Bamako Mali Social Health Service of the Armed Forces of Mali Bamako Mali Department of General Surgery “ A&#8221 and Cardiovascular of Point G University Hospital Bamako Mali Department of General Surgery of CHU Gabriel TOURE Bamako Mali

Digestive surgical emergencies concern all patients admitted urgently, for whom a decision for surgical intervention may be necessary within 24 hours. They are on guard duty day and night. To carry out this work, we set ourselves the objectives of: 1) Studying digestive surgical emergencies in the general surgery department of the “Mother Child” Le Luxembourg hospital in Bamako, Mali;2) Determine the frequency of digestive surgical emergencies, 3) Describe the clinical and therapeutic aspects, and 4) Analyze the results of treatment. from November 1, 2022 to October 31, 2023, the general surgery department of the “Mother Child” Luxembourg Hospital Center in Bamako, Mali, carried out 139 digestive surgical emergencies whose files were usable;75 men and 64 women, a sex ratio of 1.2. The 20 - 40 years old age group was the most represented, at 40.29%. The average age was 39 years;the extremes 16 years and 93 years with a standard deviation of 21.65 years. The reference concerned 51.08% of our patients. Abdominal pain was the main reason for consultation (100% of cases). In the majority of cases, the physical examination made it possible to make the diagnosis. Faced with certain clinical cases, we requested ultrasound (109/139), ASP (46/139) and CT (15/139). The main etiology was acute appendicitis with 42.45% of cases. The frequency of digestive surgical emergencies was 10.71% of all activities in the general surgery department of the “Mère Enfant” Le Luxembourg hospital center in Bamako. All our patients were seen in consultation by an anesthesiologist before entering the operating room. The surgical consequences were complicated in 11.51% of cases with 7.91% deaths. Surgical site infections accounted for 12.5% of postoperative complications. Eleven deaths were noted, representing 68.75% of complications and 7.91% of our sample. Acute peritonitis was the cause of death in 100% of cases. The average cost of care was 329,000 FCFA.

关键词： Emergency Digestive Surgery Post-Operative Complication