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轧制变形及再结晶00Cr12铁素体不锈钢中的{011}/{011}近奇异晶界

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中国科学：技术科学 2024年第3期54卷 459-476页

作者：黄新宇王卫国 ROHRER gregory S 徐刚陈松冯小铮张厚安陈文哲周邦新福建理工大学晶界工程研究所福州350118 福建理工大学材料科学与工程学院福州350118 Department of Materials Science and Engineering Carnegie Mellon UniversityPittsburgh 15213-3890USA 厦门理工学院材料科学与工程学院厦门361024 上海大学材料研究所上海200072

不同于低层错能面心立方结构的奥氏体不锈钢,高层错能体心立方结构的铁素体不锈钢在形变及再结晶等组织重构过程中很难形成结构稳定且十分耐蚀的奇异晶界(共格孪晶界).研究{011}/{011}近奇异晶界的影响因素和形成机理,将有可能为改善铁... 详细信息

不同于低层错能面心立方结构的奥氏体不锈钢,高层错能体心立方结构的铁素体不锈钢在形变及再结晶等组织重构过程中很难形成结构稳定且十分耐蚀的奇异晶界(共格孪晶界).研究{011}/{011}近奇异晶界的影响因素和形成机理,将有可能为改善铁素体不锈钢,特别是低Cr铁素体不锈钢晶间腐蚀性能提供晶界工程新思路.本文选用经固溶处理和组织均匀化处理的00Cr12低Cr铁素体不锈钢为实验材料,5个平行试样分别在350℃,500℃,580℃,650℃和690℃进行厚度减缩量为70%的单向轧制变形后,立即进行750℃、2 h再结晶退火处理.使用基于电子背散射衍射和五参数分析的晶界界面匹配表征方法对上述样品进行测试和分析发现,轧制温度对00Cr12铁素体不锈钢再结晶{011}/{011}近奇异晶界比例有显著影响,再结晶后的{011}/{011}近奇异晶界比例随再结晶退火前轧制温度的升高先上升再下降,其中经650℃轧制的样品,其再结晶后{011}/{011}近奇异晶界比例达到极大值6.82%.取向分布函数(ODF)和重叠极图晶界迹线分析表明,经650℃轧制的样品,其再结晶组织中形成了强的{011}织构;具有{011}及其漫散取向的晶粒之间较多地存在/θ取向差关系(θ为绕的旋转角),其关联晶界为{011}/{011}近奇异晶界,这是经650℃轧制的样品,其再结晶后{011}/{011}近奇异晶界比例达到极大值的原因.离线原位表面侵蚀实验表明,{011}/{011}近奇异晶界的腐蚀抗力显著高于一般晶界.因此,基于本文研究结果,进一步调控并提高{011}/{011}近奇异晶界的比例将有助于从根本上显著改善00Cr12铁素体不锈钢晶间腐蚀性能.

关键词： 00Cr12铁素体不锈钢近奇异晶界晶界界面匹配晶间腐蚀

A functional tacrolimus-releasing nerve wrap for enhancing nerve regeneration following surgical nerve repair

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Neural Regeneration Research 2025年第1期20卷 291-304页

作者： Simeon C.Daeschler Katelyn J.W.So Konstantin Feinberg Marina Manoraj Jenny Cheung Jennifer Zhang Kaveh Mirmoeini JPaul Santerre Tessa Gordon gregory HBorschel SickKids Research Institute Neuroscience and Mental Health ProgramTorontoONCanada Institute of Biomaterials and Biomedical Engineering University of TorontoTorontoONCanada Indiana University School of Medicine IndianapolisINUSA Division of Plastic and Reconstructive Surgery the Hospital for Sick ChildrenTorontoONCanada Translational Biology and Engineering Program Ted Rogers Centre for Heart ResearchInstitute of Biomedical EngineeringFaculty of DentistryUniversity of TorontoTorontoONCanada

Axonal regeneration following surgical nerve repair is slow and often incomplete,resulting in poor functional recovery which sometimes contributes to lifelong ***,there are no FDA-approved therapies available to promote nerve *** accelerates axonal regeneration,but systemic side effects presently outweigh its potential benefits for peripheral nerve *** authors describe herein a biodegradable polyurethane-based drug delivery system for the sustained local release of tacrolimus at the nerve repair site,with suitable properties for scalable production and clinical application,aiming to promote nerve regeneration and functional recovery with minimal systemic drug *** is encapsulated into co-axially electrospun polycarbonate-urethane nanofibers to generate an implantable nerve wrap that releases therapeutic doses of bioactive tacrolimus over 31 *** and drug loading are adjustable for applications in small and large caliber nerves,and the wrap degrades within 120 days into biocompatible *** released from the nerve wrap promotes axon elongation in vitro and accelerates nerve regeneration and functional recovery in preclinical nerve repair models while off-target systemic drug exposure is reduced by 80%compared with systemic *** its surgical suitability and preclinical efficacy and safety,this system may provide a readily translatable approach to support axonal regeneration and recovery in patients undergoing nerve surgery.

关键词： biodegradable local drug delivery nerve injury nerve regeneration nerve wrap tacrolimus

Burril-Bernard Crohn(1884-1983)and the disease which bears his name

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History & Philosophy of Medicine 2024年第4期6卷 16-23页

作者： Georgios Androutsos Konstantinos Laios Pavlos Lytsikas-Sarlis Evangelia Mourellou Constantinos Georgios Zografos gregory Tsoucalas Marianna Karamanou School of Medicine National and Kapodistrian University of AthensAthens 11527Greece Department of History of Medicine and Medical Ethics School of MedicineNational and Kapodistrian University of AthensAthens 11527Greece Graduate School of Medicine National and Kapodistrian University of AthensAthens 11527Greece Department of the History of Medicine and Medical Deontology School of MedicineUniversity of CreteHeraklion 71003Greece Surgery Department School of MedicineNational and Kapodistrian University of AthensAthens 11527Greece

Background:Crohn’s disease,described by *** Crohn and his colleagues in 1932,continues to be of great research and clinical *** was initially perceived as a distinct condition and it has evolved since into a complex disease,with debates still going regarding its classification and *** though more that 80 years of research have passed,numerous significant questions regarding the disease’s causes and best possible treatment strategies still ***:This article reviews both historical and contemporary perspectives on Crohn’s disease,including its initial description,the research developments that happened in the years to follow,as well as the way it is regarded *** refers to notable contributions from medical figures,such as *** and his colleagues,examines related advances made in medical research and mentions the challenges and the treatment strategies that are still being ***:This article highlights the evolution of Crohn’s disease from a distinct condition to a more heterogeneous ***,it refers to advancements made in medical research,such as the identification of CARD15(NOD2)gene mutations and the role of dysbiosis,and it examines current therapeutic ***:Even though significant progress has been made since the initial description of Chron’s disease,there is no definitive cure,even though it has been determined that genetic and environmental factors are of great *** ongoing research could possibly lead to future discoveries and therefore aid in the discovery of efficient management and treatment of Crohn’s disease.

关键词： regional ileitis granulomatous inflammation endoscopic evaluation historical figures

Organization of microtubule plus-end dynamics by phase separation in mitosis

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Journal of Molecular Cell Biology 2024年第2期16卷 24-35页

作者： Fengrui Yang Mingrui Ding Xiaoyu Song Fang Chen Tongtong Yang Chunyue Wang Chengcheng Hu Qing Hu Yihan Yao Shihao Du Phil YYao Peng Xia gregory Adams Jr Chuanhai Fu Shengqi Xiang Dan Liu Zhikai Wang Kai Yuan Xing Liu MOE Key Laboratory for Membraneless Organelles&Cellular Dynamics Hefei National Research Center for Cross-disciplinary SciencesCenter for Advanced Interdisciplinary Science and Biomedicine of IHMDivision of Life Sciences and MedicineUniversity of Science&Technology of ChinaHefei 230027China Anhui Key Laboratory for Cellular Dynamics and Chemical Biology University of Science&Technology of ChinaHefei 230027China Keck Center for Organoids Plasticity Morehouse School of MedicineAtlantaGA 30310USA Hunan Key Laboratory of Molecular Precision Medicine Central South UniversityChangsha 410083China

In eukaryotes,microtubule polymers are essential for cellular plasticity and fate ***-binding(EB)proteins serve as scaffolds for orchestrating microtubule polymer dynamics and are essential for cellular dynamics and chromosome segregation in ***,we show that EB1 forms molecular condensates with TIP150 and MCAK through liquid–liquid phase separation to compartmentalize the kinetochore–microtubule plus-end machinery,ensuring accurate kinetochore–microtubule interactions during chromosome segregation in *** of EB1–TIP150 polymer formation by a competing peptide prevents phase separation of the EB1-mediated complex and chromosome alignment at the metaphase equator in both cultured cells and Drosophila ***220 of EB1 is dynamically acetylated by p300/CBP-associated factor in early mitosis,and persistent acetylation at Lys220 attenuates phase separation of the EB1-mediated complex,dissolves droplets in vitro,and harnesses accurate chromosome *** data suggest a novel framework for understanding the organization and regulation of eukaryotic spindle for accurate chromosome segregation in mitosis.

关键词： phase separation mitosis microtubule dynamics EB1 acetylation

室温和深冷轧制对纯Al再结晶{111}/{111}近奇异晶界的影响

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金属学报 2024年

作者：李振想王卫国 gregory S Rohrer 洪丽华陈松林燕周邦新福建理工大学材料科学与工程学院福建理工大学晶界工程研究所上海大学材料研究所 Department of Material Science and Engineering Carnegie Mellon University

{111}/{111}近奇异晶界比一般晶界更耐蚀，研究此类晶界的形成条件、影响因素和生成机制，设法调控此类晶界并提高其比例是改善相关铝合金晶界腐蚀性能的根本途径。为了解铝合金生成{111}/{111}近奇异晶界的本征行为，本工作选择高纯Al ... 详细信息

{111}/{111}近奇异晶界比一般晶界更耐蚀，研究此类晶界的形成条件、影响因素和生成机制，设法调控此类晶界并提高其比例是改善相关铝合金晶界腐蚀性能的根本途径。为了解铝合金生成{111}/{111}近奇异晶界的本征行为，本工作选择高纯Al (99.99%)为实验材料，首先经室温反复多向锻造和370℃再结晶退火获得晶粒尺寸均匀、平均晶粒尺寸约为20μm且晶粒取向随机分布的组织均匀化初始样品；再将初始样品分别在室温(25℃)和-196℃深冷进行厚度减缩量为80%的轧制变形，及370℃、30 min再结晶退火处理。采用EBSD和基于五参数分析的晶界界面匹配定量表征方法对两样品进行测试和分析。结果表明，经-196℃深冷轧制并再结晶的样品，其{111}/{111}近奇异晶界比例达到6.0%，相比室温轧制并再结晶的样品提升了120%。XRD、EBSD及硬度结果表明，经室温和-196℃深冷轧制的样品中均形成了较强的{011}形变织构；较比室温轧制，经-196℃深冷轧制的样品内残余压应力更大，晶粒碎化更严重、储能更高。在后续370℃退火过程中，经室温和-196℃深冷轧制的样品，其再结晶机制均以{011}取向生长为主；较比于室温轧制，经-196℃深冷轧制的样品可提供更大的晶界迁移驱动力，其样品再结晶组织的平均晶粒尺寸更大且{011}再结晶织构更强。统计结果表明，{011}取向晶粒与其他取向的晶粒毗连所形成的晶界中存在较高比例的{111}/{111}近奇异晶界；同时，为{011}取向晶粒与其相邻的且具有{011}漫散取向的晶粒间也形成较多的{111}/{111}近奇异晶界，这是导致经-196℃深冷轧制及再结晶的样品中{111}/{111}近奇异晶界比例较高的主要原因。

关键词：高纯Al 深冷轧制近奇异晶界晶界界面匹配择尤取向

Evaluation of Spontaneous Fertility after Medical Treatment of Tubal Ectopic Pregnancy in Two Hospitals in the City of Yaounde

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Open Journal of Obstetrics and Gynecology 2024年第1期14卷 175-185页

作者： Noa Ndoua Claude Cyrille Tchedele Guidebta Hilary Nyada Serge Robert Astrid Ruth Ndolo Kondo Ayissi gregory Ngo Dingom Anne Madye Tompeen Isidore Faculty of Medicine and Biomedical Sciences of the University of Yaoundé I Yaounde Cameroon Faculty of Medicine and Pharmaceutical sciences of the University of Douala Douala Cameroon

Background: Ectopic pregnancy is a major cause of maternal morbidity and mortality, estimated to occur in 1% - 2% of pregnancies worldwide. This condition also has an adverse effect on the fertility prospects of women who experience it. Objective: To determine the outcomes of subsequent spontaneous fertility after medical treatment of patients with methotrexate (MTX) in patients with ectopic pregnancy at two university teaching hospitals of Yaounde. Methodology: We carried out a cross-sectional study with retrospective data collection in two university teaching hospitals of Yaounde during a six years period from 1st January 2015 to 31st May 2021. Seventy records of patients who had medical treatment for ectopic pregnancy were included in this study. Statistical analysis was performed using SPSS. 23. The Chi-2 statistical test was used to compare qualitative variables. Binary logistic regression method was performed to identify independent risk factors associated with infertility after medical treatment of tubal ectopic pregnancy (TEP). The significance level was set at 0.05. Results: The mean age in our study population was 27.8 ± 3.8 years. According to the past medical history, 52.9% had a pelvic inflammatory disease (PID) and the most frequently germ found was C. trachomatis (47.1%). Almost 15% of our study population had previous surgery for EP. The median Fernandez score was 11 with a minimum score of 4 and a maximum score of 13. The route of administration of methotrexate was intramuscular in all our patients, and the single-dose protocol was used most frequently (58.6%). After medical treatment of the EP, we found a spontaneous conception rate of 58.6%. After multivariate analysis, we were unable to confirm that there was an association between a history of sexually transmitted infections (STIs) and fertility prognosis. Conclusion: The spontaneous fertility rate after medical management of EP was 58.6%, of which 73.2% were term pregnanci

关键词： Ectopic Pregnancy Maternal Morbidity

Optical monitoring of particle aggregates

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Journal of Environmental Sciences 2009年第1期21卷 2-7页

作者： John gregory Department of Civil Environmental and Geomatic EngineeringUniversity College London

Methods for monitoring particle aggregation are briefly reviewed. Most of the techniques are based on some form of light scattering and may be greatly dependent on the optical properties of aggregates, which are not generally known. As fractal aggregates grow larger their density can become very low and this has important practical consequences for light scattering. For instance, the scattering coefficient may be much less than for solid objects, which means that the aggregates can appear much smaller than their actual size by a light transmission method. Also, for low-density objects, a high proportion of the scattered light energy is within a small angle of the incident beam, which may also be relevant for measurements with aggregates. Using the ＂turbidity fluctuation＂ technique as an example, it is shown how the apparent size of hydroxide flocs depends mainly on the included impurity particles, rather than the hydroxide precipitate itself. Results using clay suspensions with hydrolyzing coagulants and polymeric floceulants under different string conditions are discussed.

关键词： monitoring method flocculation turbidity fluctuation

Association between Exposure to Metals during Pregnancy,Childhood Gut Microbiome,and Risk of Intestinal Inflammation in Late Childhood

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Environment & Health 2024年第10期2卷 739-749页

作者： Vishal Midya Manasi Agrawal Jamil M.Lane Chris Gennings Leonid Tarassishin Libni A.Torres-Olascoaga Joseph Eggers Jill K.gregory Mellissa Picker Inga Peter Jeremiah J.Faith Manish Arora Martha M.Tellez-Rojo Robert O.Wright Jean-Frederic Colombel Shoshannah Eggers Department of Environmental Medicine and Climate Science Icahn School of Medicine at Mount SinaiNew York 10029-6574New YorkUnited States Division of Gastroenterology Icahn School of Medicine at Mount SinaiNew York 10029-6574New YorkUnited States Center for Molecular Prediction of Inflammatory Bowel Disease(PREDICT) Department of Clinical MedicineAalborg UniversityCopenhagen 9220Denmark Department of Genetics and Genomic Sciences Icahn School of MedicineNew York 10029-6574New YorkUnited States Center for Research on Nutrition and Health National Institute of Public HealthCuernavaca 62508Mexico Department of Immunology and Immunotherapy Icahn School of Medicine at Mount SinaiNew York 10029-6574New YorkUnited States Department of Epidemiology University of Iowa College of Public HealthIowa City 52242 IowaUnited States Instructional Technology Group Icahn School of Medicine at Mount SinaiNew York 10029-6574New YorkUnited States

Alterations to the gut microbiome and exposure to metals during pregnancy have been suggested to impact inflammatory bowel ***,how prenatal exposure to metals eventually results in long-term effects on the gut microbiome,leading to subclinical intestinal inflammation,particularly during late childhood,has not been *** is also unknown whether such an interactive effect drives a specific subgroup of children toward elevated susceptibility to intestinal *** used an amalgamation of machine-learning techniques with a regression-based framework to explore if children with distinct sets of gut microbes and certain patterns of exposure to metals during pregnancy(metal−microbial clique signature)had a higher likelihood of intestinal inflammation,measured based on fecal calprotectin(FC)in late *** obtained samples from a well-characterized longitudinal birth cohort from Mexico City(n=108),*** the second and third trimesters of pregnancy,11 metals were measured in whole *** microbial abundances and FC were measured in stool samples from children 9−11 years of *** FC was defined as having FC above 100μg/g of *** identified subgroups of children in whom microbial and metal−microbial clique signatures were associated with elevated FC(false discovery rate(FDR)<0.05).In particular,we found two metal−microbial clique signatures significantly associated with elevated FC:(1)low cesium(Cs)and copper(Cu)in the third trimester and low relative abundance of Eubacterium ventriosum(OR[95%CI]:10.27[3.57,29.52],FDR<0.001)and(2)low Cu in the third trimester and high relative abundances of Roseburia inulinivorans and Ruminococcus torques(OR[95%CI]:7.21[1.81,28.77],FDR<0.05).This exploratory study demonstrates that children with specific gut microbes and specific exposure patterns to metals during pregnancy may have higher fecal calprotectin levels in late childhood,denoting an elevated risk of intestinal inflammation.

关键词： exposome metals machine learning microbiome environmental epidemiology intestinal inflammation

Assessing risks from mining-induced ground movements near gas wells

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International Journal of Mining Science and Technology 2020年第1期30卷 11-16页

作者： Christopher Mark gregory M.Rumbaugh Mine Safety and Health Administration PittsburghPAUSA

The proliferation of unconventional gas well development in the Northern Appalachian coalfields has raised a number of mine safety *** wells,which extract gas from deep shale formations,are characterized by gas volumes and pressures that are significantly higher than those observed at many conventional *** gas is composed largely of methane as well as other *** of planned and actively producing wells penetrate protective coal pillars or barriers within active mine boundaries,including chain pillars located between longwall *** released from a well damaged by mining-induced ground movements could pose a risk to miners by flowing into the mine *** mining-induced ground movements that may cause well damage include conventional subsidence,non-conventional subsidence(*** plane slip),pillar failure,and floor *** paper describes the known risk factors for each of the four failure *** includes a framework that can guide the risk assessment process when mining takes place near gas or oil wells.

关键词： Gas well Subsidence Coal protection pillar Risk matrix Longwall mining