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Cellular & Molecular Immunology 2024年第4期21卷 409-411页

作者： dieter Kabelitz Institute of Immunology University of KielKielGermany

Members of the butyrophilin(BTN)family of transmembrane molecules play an important role in the activation of humanγδT cells.In recent years,it has been discovered that BTN3A1 and BTN2A1 are indispensable in this process,but other members like BTN3A2 and BTN3A3 are also required.So far,very little is known about the transcriptional and post-translational regulation of BTN expression.

关键词： expression. insight critical

Shape-changing particles for locally resolved particle geometry in DEM simulations

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Particuology 2024年第6期89卷 185-190页

作者： Enric Illana Klidi Qyteti Maik Scharnowski Maximilian brömmer Siegmar Wirtz Viktor Scherer Institute of Energy Plant Technology Ruhr-University BochumBochumGermany

Taking into account the complex shape of particles in discrete element method (DEM) simulations of large-scale granular systems is computationally demanding due to the time-consuming contact detection algorithms for polyhedral particles. In this short communication, a novel approach that locally resolves the particle shapes where needed and uses a simplified representation elsewhere, to accelerate simulations without compromising accuracy, is presented. For this purpose, a method employing a smooth transition of the particle shape representation from analytical spheres to shape-resolving polyhedra is introduced in DEM. The feasibility and correct implementation of this approach are demonstrated through simulations of hopper discharge involving spherical and dodecahedral particles from a flat bottom silo or shaft kiln. The model capabilities, in terms of accuracy as well as reduction in computational effort, are quantified for a moving bed with continuous outflow.

关键词： Polyhedron Size change Shape change Locally resolved DEM

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 programs.The rapid development in this field documented in an increasing number of publications requires a comprehensive review.This study includes a bibliometric analysis-based review to better understand research trends in tree ring stable isotope research.Overall,1475 publications were selected from the Web of Science Core Collection for 1974-2023.The findings are that:(1)numbers of annual publications and citations increased since 1974.From 1974 to 1980,there were around two relevant publications per year.However,from 2020 to 2022,this rose sharply to 109 publications per year.Likewise,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 topics.Since 2010,precipitation and drought have received increasing attention.Based on this analysis,the research stages,key findings,debated issues,limitations and direc-tions for future research are summarized.This 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

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 resolved.This 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 realized.As 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 investigated.In an experimental setup,the vertical profile of the pressure decay through the inlet and across the packing is chosen for com-parison with respective simulations.Results 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 shapes.Spheres of different size as well as dodecahedrons are examined.It 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

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

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VHD（VAD）流程技术的新生

国际冶金设备和技术 2011年第2期 18-20页

作者： Johannes Obitz dieter brück Roland Kristl Inteco special melting technologies GmbH Bruck a.d. MurAustria

真空加热脱气（VHD）-真空电弧脱气（VAD）作为炼钢领域一种公认的技术已有40多年的历史。目前还有理由对这种设备技术进行投资重新设计吗？本文从VHD设备的工程角度进行了讨论。冶金方面的考虑主要基于对仍在运转的VHD设备的经验积累... 详细信息

真空加热脱气（VHD）-真空电弧脱气（VAD）作为炼钢领域一种公认的技术已有40多年的历史。目前还有理由对这种设备技术进行投资重新设计吗？本文从VHD设备的工程角度进行了讨论。冶金方面的考虑主要基于对仍在运转的VHD设备的经验积累和相关报道。

关键词：设备技术新生真空电弧真空加热经验积累 VHD 脱气工程

The Vγ4/butyrophilin conspiracy: novel role of intraepithelial γδ T cells in chronic inflammatory bowel disease

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Signal Transduction and Targeted Therapy 2023年第12期8卷 5575-5577页

作者： dieter Kabelitz Institute of Immunology Christian-Albrechts University Kiel and University Hospital Schleswig-Holstein Campus KielKielGermany

In a recent article published in Science,Dart and colleagues reported that colonic T cells expressing the Vγ4 T-cell receptor(TCR)interact with epithelial butyrophilin-like(BTNL)proteins BTNL3 and BTNL8 in healthy individuals,and they observed a depletion of Vγ4 T cells in inflammatory bowel diseases with renormalization associated with disease remission.1 This paper identifies the BTNL/Vγ4 axis as a new disease modifier in IBD.

关键词： bowel inflammatory diseases

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VHD工艺和成果

VHD工艺和成果

Comparing two IBM implementations for the simulation of uniform packed beds

第十八届（2014年）全国炼钢学术会议

作者： Christian Redl Matthias Pfennig Johannes Obitz dieter brück 白彦贵奥地利因泰克特种冶炼公司

VHD真空加热脱气或VAD真空电弧脱气技术在炼钢领域投产到现在已有40多年。虽然在世界范围内仅有少数这种设备在使用,但是有很多原因促使投资开发这种技术。随着设计方面的改进提高了VHD的竞争地位,它可对钢包精炼炉（LF）和真空脱气（V... 详细信息

VHD真空加热脱气或VAD真空电弧脱气技术在炼钢领域投产到现在已有40多年。虽然在世界范围内仅有少数这种设备在使用,但是有很多原因促使投资开发这种技术。随着设计方面的改进提高了VHD的竞争地位,它可对钢包精炼炉（LF）和真空脱气（VD）进行有效的和先进的组合替代。本文讨论了在中国钢厂投产的VHD项目的设计和工程方面的问题以及调试经验和生产成果。

关键词： VHD VAD 低气体含量低增碳减少夹杂脱硫

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Particuology 2024年第3期86卷 1-12页

作者： Christian Gorges Maximilian brommer Christin Velten Siegmar Wirtz Enric Illana Mahiques Viktor Scherer Katharina Zahringer Berend van Wachem Mechanical Process Engineering Otto-von-Guericke-Universitat MagdeburgUniversitatsplatz 239106MagdeburgGermany Department of Energy Plant Technology Ruhr-Universitat BochumUniversitatsstraBe 15044780BochumGermany Laboratory of Fluid Dynamics and Technical Flows Otto-von-Guericke-Universitat MagdeburgUniversitatsplatz 239106MagdeburgGermany

Nowadays,the design of fixed packed bed reactors still relies on empirical correlations,which,especially for small tube to particle diameter ratios,are mostly too inaccurate because of the presence of wall effects.Therefore,the simulation of fixed packed bed reactors plays an important role to predict and control the flow and process parameters in such,nowadays and in the future.Because of its straightforward applicability to non-uniform packings with particles of arbitrary shapes,the immersed boundary method(IBM)has advantages over other numerical methods and is used more and more frequently.This paper compares two approaches of IBMs for the simulation of fixed bed reactors with spherical shaped particles.The classic,smooth approach is compared to the straightforward to implement blocked-off method for velocity fields above the fixed bed for particle Reynolds numbers of 300 and 500.Results from experimental inline PIV-measurements of the reactor to be simulated serve as a basis for comparison.Very good agreement with the experiment is found for both simulation methodologies with higher resolutions,considering the more stable flow at a particle Reynolds number of 300.Differences in the different IBM approaches occurred for the more unsteady flow at a particle Reynolds number of 500.Compared to the blocked-off method,the smooth IBM reflects the formation of additional jets and recirculation zones better right above the bed,though increasing the fluid mesh resolution improves the accuracy of the blocked-off method.Overall,a more diffusive behaviour is found for the blocked-off simulations due to the stairstep representation,which is avoided by using interpolation stencils as in the smooth IBM.With higher mesh refinement in the blocked-off IBM this effect can be reduced,but this also increases the computational effort.

关键词： Immersed boundary method Packed bed reactor Uniform particle packing