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Small bowel capsule endoscopy in 2007:Indications,risks and limitations 被引量:30
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作者 Emanuele Rondonotti Federica Villa +2 位作者 Chris JJ Mulder Maarten AJM jacobs Roberto de Franchis 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第46期6140-6149,共10页
Capsule endoscopy has revoluzionized the study of the small bowel by providing a reliable method to evaluate, endoscopically, the entire small bowel. In the last six years several papers have been published exploring ... Capsule endoscopy has revoluzionized the study of the small bowel by providing a reliable method to evaluate, endoscopically, the entire small bowel. In the last six years several papers have been published exploring the possible role of this examination in different clinical conditions. At the present time capsule endoscopy is generally recommended as a third examination, after negative bidirectional endoscopy, in patients with obscure gastrointestinal bleeding. A growing body of evidence suggests also an important role for this examination in other clinical conditions such as Crohn's disease, celiac disease, small bowel polyposis syndromes or small bowel tumors. The main complication of this examination is the retention of the device at the site of a previously unknown small bowel stricture. However there are also some other open issues mainly due to technical limitations of this tool (which is not driven from remote control, is unable to take biopsies, to insufflate air, to suck fluids or debris and sometimes to correctly size and locate lesions).The recently developed double balloon enteroscope, owing to its capability to explore a large part of the small bowel and to take targeted biopsies, although being invasive and time consuming, can overcome some limitations of capsule endoscopy. At the present time, in the majority of clinical conditions (i.e. obscure GI bleeding), the winning strategy seems to be to couple these two techniques to explore the small bowel in a painless, safe and complete way (with capsule endoscopy) and to define and treat the lesions identified (with double balloon enteroscopy). 展开更多
关键词 Capsule endoscopy Double balloon
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短碳纤维增强注塑聚醚醚酮复合材料微观结构与力学性能研究 被引量:20
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作者 钟明强 益小苏 jacobs O 《复合材料学报》 EI CAS CSCD 北大核心 2002年第1期12-16,共5页
实验结果表明 :短碳纤维增强注塑聚醚醚酮 (CF/ PEEK)注塑板材中存在“皮 -芯”次层微结构 ,用金相显微镜可以表征 CF取向度不同的皮层和芯层的厚度 ,整板材料的力学性能可以根据皮层及芯层的厚度及其强度按“混合规则”计算。 DSC法及... 实验结果表明 :短碳纤维增强注塑聚醚醚酮 (CF/ PEEK)注塑板材中存在“皮 -芯”次层微结构 ,用金相显微镜可以表征 CF取向度不同的皮层和芯层的厚度 ,整板材料的力学性能可以根据皮层及芯层的厚度及其强度按“混合规则”计算。 DSC法及热烘箱法研究表明 ,碳纤维取向结构和 展开更多
关键词 聚醚醚酮 短碳纤维 注塑 微观结构 力学性能 复合材料 工程塑料 增强作用
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New frontiers for the materials genome initiative 被引量:22
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作者 Juan J.de Pablo Nicholas E.Jackson +21 位作者 Michael A.Webb Long-Qing Chen Joel E.Moore Dane Morgan Ryan jacobs Tresa Pollock Darrell G.Schlom Eric S.Toberer James Analytis Ismaila Dabo Dean M.DeLongchamp Gregory A.Fiete Gregory M.Grason Geoffroy Hautier Yifei Mo Krishna Rajan Evan J.Reed Efrain Rodriguez Vladan Stevanovic Jin Suntivich Katsuyo Thornton Ji-Cheng Zhao 《npj Computational Materials》 SCIE EI CSCD 2019年第1期776-798,共23页
The Materials Genome Initiative(MGI)advanced a new paradigm for materials discovery and design,namely that the pace of new materials deployment could be accelerated through complementary efforts in theory,computation,... The Materials Genome Initiative(MGI)advanced a new paradigm for materials discovery and design,namely that the pace of new materials deployment could be accelerated through complementary efforts in theory,computation,and experiment.Along with numerous successes,new challenges are inviting researchers to refocus the efforts and approaches that were originally inspired by the MGI.In May 2017,the National Science Foundation sponsored the workshop“Advancing and Accelerating Materials Innovation Through the Synergistic Interaction among Computation,Experiment,and Theory:Opening New Frontiers”to review accomplishments that emerged from investments in science and infrastructure under the MGI,identify scientific opportunities in this new environment,examine how to effectively utilize new materials innovation infrastructure,and discuss challenges in achieving accelerated materials research through the seamless integration of experiment,computation,and theory.This article summarizes key findings from the workshop and provides perspectives that aim to guide the direction of future materials research and its translation into societal impacts. 展开更多
关键词 utilize FRONTIER ACCOMPLISHMENT
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利用直接激发Rayleigh表面波的方法测量材料的声学非线性系数 被引量:19
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作者 税国双 汪越胜 +2 位作者 Jianmin Qu Jin-Yeon Kim Laurence J. jacobs 《声学学报》 EI CSCD 北大核心 2008年第4期378-384,共7页
提出了利用直接激发Rayleigh表面波的方法测量材料的声学非线性系数。采用专门的信号源,将压电传感器安装在试件边缘直接激发Rayleigh表面波,利用激光干涉仪测量系统采集试件表面的Rayleigh波信号。对采集到的Rayleigh波信号进行FFT变换... 提出了利用直接激发Rayleigh表面波的方法测量材料的声学非线性系数。采用专门的信号源,将压电传感器安装在试件边缘直接激发Rayleigh表面波,利用激光干涉仪测量系统采集试件表面的Rayleigh波信号。对采集到的Rayleigh波信号进行FFT变换,得到Rayleigh波信号中所包含的基频和高频成分,并据此进一步确定材料的声学非线性系数。对铝合金材料AA2024和AA6061的试验测量与分析结果表明,这种利用将压电传感器直接安装在试件边缘激发Rayleigh表面波的方法能够有效、准确地测量材料的声学非线性系数,可以为材料和结构早期力学性能退化的无损检测和评价提供一种有效的途径。 展开更多
关键词 Rayleigh表面波 干涉仪测量系统 铝合金材料 非线性系数 RAYLEIGH波 声学 激发 传感器安装
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短玻纤增强聚丙烯注射压力对微观结构和力学性能影响 被引量:15
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作者 钟明强 濮阳楠 +1 位作者 益小苏 jacobs O 《复合材料学报》 EI CAS CSCD 北大核心 2000年第4期6-10,共5页
报道了短玻纤增强聚丙烯复合材料中玻纤及注射压力对材料微观结构和力学性能的影响规律。实验结果表明 :随着玻纤含量提高 ,复合材料的拉伸强度提高 ,而断裂伸长率、冲击强度和熔体流动速率则下降。注射压力提高 ,拉伸试样芯层中玻纤的... 报道了短玻纤增强聚丙烯复合材料中玻纤及注射压力对材料微观结构和力学性能的影响规律。实验结果表明 :随着玻纤含量提高 ,复合材料的拉伸强度提高 ,而断裂伸长率、冲击强度和熔体流动速率则下降。注射压力提高 ,拉伸试样芯层中玻纤的平均取向角下降 ,取向度提高 ,因而拉伸强度增大 ,冲击强度下降。皮层结构中玻纤沿熔体流动方向高度取向。聚丙烯球晶尺寸随玻纤含量增加而变小 ,规整度也变差 ,至 40 %时 ,聚丙烯已难以形成规整的球晶结构。 展开更多
关键词 短玻纤 注射压力 微观结构 聚丙烯复合材料
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2024 Adult Compendium of Physical Activities:A third update of the energy costs of human activities 被引量:9
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作者 Stephen D.Herrmann Erik A.Willis +10 位作者 Barbara E.Ainsworth Tiago V.Barreira Mary Hastert Chelsea L.Kracht John M.Schuna Jr. Zhenghui Cai Minghui Quan Catrine Tudor-Locke Melicia C.Whitt-Glover David R. jacobs Jr. 《Journal of Sport and Health Science》 SCIE CSCD 2024年第1期6-12,共7页
Background:The Compendium of Physical Activities was published in 1993 to improve the comparability of energy expenditure values assigned to self-reported physical activity(PA)across studies.The original version was u... Background:The Compendium of Physical Activities was published in 1993 to improve the comparability of energy expenditure values assigned to self-reported physical activity(PA)across studies.The original version was updated in 2000,and again in 2011,and has been widely used to support PA research,practice,and public health guidelines.Methods:This 2024 update was tailored for adults 19-59 years of age by removing data from those≥60 years.Using a systematic review and supplementary searches,we identified new activities and their associated measured metabolic equivalent(MET)values(using indirect calorimetry)published since 2011.We replaced estimated METs with measured values when possible.Results:We screened 32,173 abstracts and 1507 full-text papers and extracted 2356 PA energy expenditure values from 701 papers.We added303 new PAs and adjusted 176 existing MET values and descriptions to reflect the addition of new data and removal of METs for older adults.We added a Major Heading(Video Games).The 2024 Adult Compendium includes 1114 PAs(912 with measured and 202 with estimated values)across 22 Major Headings.Conclusion:This comprehensive update and refinement led to the creation of The 2024 Adult Compendium,which has utility across research,public health,education,and healthcare domains,as well as in the development of consumer health technologies.The new website with the complete lists of PAs and supporting resources is available at https://pacompendium.com. 展开更多
关键词 ADULTS Energy expenditure EXERCISE MET Physical Activities
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一个关于工作场所学习的建议性概念框架:对人力资源开发理论建设与研究的启示 被引量:15
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作者 Ronald L. jacobs 李宇晴(译) 《中国职业技术教育》 北大核心 2010年第6期41-49,共9页
人力资源开发领域的学者和实践者都非常关注工作场所学习。关于正式培训和非正式学习,一直以来形成了大量的研究和讨论。本文从人力资源开发角度,结合已有的大量文献,提出了一个工作场所学习的概念性框架.框架包括三个互相作用的变... 人力资源开发领域的学者和实践者都非常关注工作场所学习。关于正式培训和非正式学习,一直以来形成了大量的研究和讨论。本文从人力资源开发角度,结合已有的大量文献,提出了一个工作场所学习的概念性框架.框架包括三个互相作用的变量:学习的场所、在发展和传授学习经验时所制定的计划的程度和学习过程中培训者、推动者和其他人的角色。本文还讨论了这一框架对人力资源开发领域中理论建设和研究的启示。 展开更多
关键词 工作场所学习 概念框架 人力资源开发
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国际胃袖状切除专家共识:基于>12000手术病例的最佳操作指南 被引量:12
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作者 苏远涛 徐安安 +27 位作者 朱江帆 Diaz AA Arvidsson D Baker RS Basso N Bellanger D Boza C El Mourad H France M Gagner M Galvao-Neto M Higa KD Himpens J Hutchinson CM jacobs M Jorgensen JO Jossart G Lakdawala M Nguyen NT Nocca D Prager G Pomp A Ramos AC Rosenthal RJ Shah S Vix M Wittgrove A Zundel N 《中国微创外科杂志》 CSCD 2013年第9期803-805,共3页
腹腔镜胃袖状切除术(1aparoscopic sleeve gastrectomy,LSG)系相对较新的减重手术方式。因其操作相对简单、治疗肥胖合并疾病及减重效果明显,逐步得以广泛接受。目前美国代谢与减重手术协会将其推荐为肥胖症治疗的单独标准术式。201... 腹腔镜胃袖状切除术(1aparoscopic sleeve gastrectomy,LSG)系相对较新的减重手术方式。因其操作相对简单、治疗肥胖合并疾病及减重效果明显,逐步得以广泛接受。目前美国代谢与减重手术协会将其推荐为肥胖症治疗的单独标准术式。2011年3月25~26日, 展开更多
关键词 袖状切除术 手术方式 操作 指南 病例 专家 国际 减重效果
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Platelet-rich plasma for regeneration of neural feedback pathways around dental implants: a concise review and outlook on future possibilities 被引量:11
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作者 Yan Huang Michael M Bornstein +3 位作者 Ivo Lambrichts Hai-Yang Yu Constantinus Politis Reinhilde jacobs 《International Journal of Oral Science》 SCIE CAS CSCD 2017年第1期1-9,共9页
Along with the development of new materials, advanced medical imaging and surgical techniques, osseointegrated dental implants are considered a successful and constantly evolving treatment modality for the replacement... Along with the development of new materials, advanced medical imaging and surgical techniques, osseointegrated dental implants are considered a successful and constantly evolving treatment modality for the replacement of missing teeth in patients with complete or partial edentulism. The importance of restoring the peripheral neural feedback pathway and thus repairing the lack of periodontal rnechanoreceptors after tooth extraction has been highlighted in the literature. Nevertheless, regenerating the nerve fibers and reconstructing the neural feedback pathways around osseointegrated implants remain a challenge. Recent studies have provided evidence that platelet-rich plasma (PRP) therapy is a promising treatment for musculoskeletal injuries. Because of its high biological safety, convenience and usability, PRP therapy has gradually gained popularity in the clinical field Although much remains to be learned, the growth factors from PRP might play key roles in peripheral nerve repair mechanisms. This review presents known growth factors contributing to the biological efficacy of PRP and illustrates basic and (pre-)clinical evidence regarding the use of PRP and its relevant products in peripheral nerve regeneration. In addition, the potential of local application of PRP for structural and functional recovery of iniured peripheral nerves around dental implants is discussed. 展开更多
关键词 neural regeneration osseoperception peripheral nerve degeneration peri-implant sensory feedback platelet-rich plasma
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Acute necrotizing pancreatitis as fi rst manifestation of primary hyperparathyroidism 被引量:10
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作者 Jeroen I Lenz Jimmy M jacobs +3 位作者 Bart Op de Beeck Ivan A Huyghe Paul A Pelckmans Tom G Moreels 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第23期2959-2962,共4页
We report the case of a female patient with severe acute necrotizing pancreatitis associated with hypercalcemia as first manifestation of primary hyperparathyroidism caused by a benign parathyroid adenoma.Initially th... We report the case of a female patient with severe acute necrotizing pancreatitis associated with hypercalcemia as first manifestation of primary hyperparathyroidism caused by a benign parathyroid adenoma.Initially the acute pancreatitis was treated conservatively.The patient subsequently underwent surgical resection of the parathyroid adenoma and surgical clearance of a large infected pancreatic pseudocyst.Although the association of parathyroid adenoma-induced hypercalcemia and acute pancreatitis is a known medical entity,it is very uncommon.The pathophysiology of hypercalcemia-induced acute pancreatitis is therefore not well known,although some mechanisms have been proposed.It is important to treat the provoking factor.Therefore,the cause of hypercalcemia should be identif ied early.Surgical resection of the parathyroid adenoma is the ultimate therapy. 展开更多
关键词 Acute necrotizing pancreatitis HYPERCALCEMIA Primary hyperparathyroidism Parathyroid adenoma
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Double balloon endoscopy associated pancreatitis:A description of six cases 被引量:8
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作者 Soeresh VA Jarbandhan Stijn JB van Weyenberg +3 位作者 Willem M van der Veer Dimitri GN Heine Chris JJ Mulder Maarten AJM jacobs 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第5期720-724,共5页
AIM:To perform a single-center analysis of all double balloon endoscopy (DBE) related cases of pancreatitis identified prospectively from a recorded DBE-complication database. METHODS:From November 2003 until January ... AIM:To perform a single-center analysis of all double balloon endoscopy (DBE) related cases of pancreatitis identified prospectively from a recorded DBE-complication database. METHODS:From November 2003 until January 2007, 603 DBE procedures were performed on 412 patients, with data on complications recorded in a database. The setting was a tertiary care center offering DBE. DBE was performed from the antegrade or retrograde route. Out-come measurements included age, gender, medication, indication, DBE-endoscope type, insertion depth, proce-dure duration, findings, interventions, post-procedural abdominal pain, and post-procedural hospitalization. RESULTS:This is the largest single-center study report-ing on post-DBE pancreatitis prospectively. Six patients (1.0%) developed post-DBE pancreatitis, all after antegrade DBE. There was no association with gender, duration of the procedure or type of endoscope. The mean age was 51.9 years (range 25-78). Four patients had severe pancreatitis. Of these, two had inflammatory signs in the body-tail region, one had pancreatitis in the tail region, and the total pancreas was involved in one. CONCLUSION:The incidence of post-DBE pancreatitis in our series is higher than previously reported. We found no relation with DBE-endoscope type. The inflammatory changes occurred in the body-tail region of the pancreas, suggesting that post-DBE pancreatitis is caused by repetitive mechanical strain on the pancreas. 展开更多
关键词 Double balloon endoscopy Small intestine Adverse events COMPLICATIONS PANCREATITIS ENTEROSCOPY
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Sensory innervation around immediately vs. delayed loaded implants: a pilot study 被引量:7
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作者 Yan Huang Jeroen van Dessel +6 位作者 Wendy Martens Ivo Lambrichts Wei-Jian Zhong Guo-Wu Ma Dan Lin Xin Liang Reinhilde jacobs 《International Journal of Oral Science》 SCIE CAS CSCD 2015年第1期49-55,共7页
Although neurophysiological and psychophysical proof of osseoperception is accumulating, histomorphometric evidence for the neural mechanisms of functional compensation following immediate and delayed implant loading ... Although neurophysiological and psychophysical proof of osseoperception is accumulating, histomorphometric evidence for the neural mechanisms of functional compensation following immediate and delayed implant loading is still lacking. For this randomized split-mouth study, six mongrel dogs randomly received one of four treatment protocols at 36 implant-recipient sites over 16 weeks (third maxillary incisor, third and fourth mandibular premolar): immediate implant placement and immediate loading (liP+ IL); delayed implant placement and delayed loading (DIP+DL); delayed implant placement and immediate loading (DIP+IL); and natural extraction socket healing (control). Histomorphometry was performed in the peri-implant bone and soft tissues within 300 pm around the implants. Immunocytochemistry and transmission electron microscopy were used to confirm the presence of neural structures and to reveal their ultrastructural characteristics, respectively. Myelinated nerve fibres densely populated the peri-implant crestal gingival and apical regions, although they were also identified in the woven bone and in the osteons near the implant threads. Compared with the control group in the mandible, the group that received IIP+IL showed a higher innervation (in N.mm^-2, 5.94±1.12 vs. 3.15±0.63, P〈0.001) and smaller fibre diameter (in pm, 1.37±0.05 vs. 1.64±0.13, P=0.016), smaller axon diameter (in pm, 0.89±0.05 vs. 1.24±0,10, P=0.009) and g-ratio (0.64±0.04 vs. 0.76±0.05, P〈0.001) in the middle region around the implants. Compared with DIP+IL in the mandible, IIP+IL had a higher nerve density (in N.mm^-2, 13.23±2.54 vs. 9.64±1.86, P=0.027), greater fibre diameter (in pm, 1.32±0.02 vs. 1.20±0.04, P=0.021), greater axon diameter (in μm, 0.92±0.01 vs. 0.89±0.03, P=-0.035) and lower g-ratio (0.69±0.01 vs. 0.74±0.01, P=-0.033) in the apical region around the implants. It may be assumed that the treatment protocol with liP+ IL is the preferred me 展开更多
关键词 animal experiments dental implants HISTOMORPHOMETRY immediate loading MECHANORECEPTOR myelinated nerve fibres osseoperception
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A Case Study of Ocean-Atmosphere Interactions during the Passage of an Extra-Tropical Cyclone in the Vicinity of Cape Hatteras, North Carolina
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作者 Neil jacobs James Churchill +2 位作者 Leonard Pietrafesa Shaowu Bao Paul Gayes 《International Journal of Geosciences》 2023年第9期855-876,共22页
The authors document the interaction of the atmosphere and ocean during the formation and passage of an Extra-Tropical Cyclone, which is a Nor-Easter, winter storm that formed in the southern apex of the Middle Atlant... The authors document the interaction of the atmosphere and ocean during the formation and passage of an Extra-Tropical Cyclone, which is a Nor-Easter, winter storm that formed in the southern apex of the Middle Atlantic Bight near Cape Hatteras North Carolina, between February 15 and 18, 1996. While Nor-Easters per se, which have formed along the Atlantic Eastern Seaboard of the United States have been studied for decades, the actual atmospheric-oceanic mechanics and thermodynamics in the formation of a Nor-Easter has never been documented. We report on having done so with in-situ observations and data-based calculations and a numerical model. The in-situ observations were made via a Control Volume consisting of an array of Eulerian Oceanic-Atmospheric Moorings with current meters, temperature and salinity sensors and meteorological towers. We find that Gulf Stream waters were located surrounding the mooring array, and that with the invasion of cold dry atmospheric air, there was a rapid loss of heat from the ocean to the atmosphere via latent and sensible surface heat flux during the cyclogenesis onset of the storm. A unique feature of this storm was that neither satellite nor buoy data showed significant sea surface cooling in the control volume. The findings indicate that storm winds drove warm saline waters from the Gulf Stream across the continental shelf into the control volume, accounting for a 51 cm rise in water level along the coast. This lateral heat advection provided heat to the control volume of 3.4e+18 Joules. On average, the heat loss at the surface of the control volume, via sensible and latent heat fluxes and radiation, was 0.7e+18 Joules, corresponding to a surface heat flux of -600 Watts per Meter2 (W/m<sup>2</sup>). However, the heat lost by the control volume as latent and sensible heat fluxes was less than the heat it received via lateral heat advection, resulting in the lack of an often-observed sea surface cooling during other winter storms. The serendipitous and detailed observations and 展开更多
关键词 Mid-Latitude Cyclone Extra-Tropical Cyclone CYCLOGENESIS Nor’easter Winter Storms Latent and Sensible Heat Fluxes Salt Flux
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Bayesian inference-based wear prediction method for plain bearings under stationary mixed-friction conditions
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作者 Florian KÖNIG Florian WIRSING +3 位作者 Georg jacobs Rui HE Zhigang TIAN Ming J.ZUO 《Friction》 SCIE EI CAS CSCD 2024年第6期1272-1282,共11页
This study introduces a method to predict the remaining useful life(RUL)of plain bearings operating under stationary,wear-critical conditions.In this method,the transient wear data of a coupled elastohydrodynamic lubr... This study introduces a method to predict the remaining useful life(RUL)of plain bearings operating under stationary,wear-critical conditions.In this method,the transient wear data of a coupled elastohydrodynamic lubrication(mixed-EHL)and wear simulation approach is used to parametrize a statistical,linear degradation model.The method incorporates Bayesian inference to update the linear degradation model throughout the runtime and thereby consider the transient,system-dependent wear progression within the RUL prediction.A case study is used to show the suitability of the proposed method.The results show that the method can be applied to three distinct types of post-wearing-in behavior:wearing-in with subsequent hydrodynamic,stationary wear,and progressive wear operation.While hydrodynamic operation leads to an infinite lifetime,the method is successfully applied to predict RUL in cases with stationary and progressive wear. 展开更多
关键词 plain bearings wear modeling remaining useful life prediction Bayesian inference
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择期髋膝关节置换患者静脉血栓栓塞性疾病预防的AAOS指南 被引量:6
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作者 Mont MA jacobs JJ +1 位作者 余霄 俞光荣 《中华关节外科杂志(电子版)》 CAS 2012年第4期84-87,共4页
本临床实践指南是对2007年已发表的一个类似指南进行撤换。我们根据现有的文献,对患者的筛选,危险因素的评估,静脉血栓疾病(VTED)的预防性治疗,鼓励患者术后活动以及使用椎管内麻醉和下腔静脉过滤器等各方面进行了评估。我们建议对有静... 本临床实践指南是对2007年已发表的一个类似指南进行撤换。我们根据现有的文献,对患者的筛选,危险因素的评估,静脉血栓疾病(VTED)的预防性治疗,鼓励患者术后活动以及使用椎管内麻醉和下腔静脉过滤器等各方面进行了评估。我们建议对有静脉血栓栓塞性疾病病史但没有其他潜在危险因素的患者需要进行进一步的评估,患者应评估是否患有某些已知的出血性疾病以及是否存在活动性的肝脏疾病。没有VTED或出血高风险的患者也应接受药物及机械压缩装置来预防VTED的发生,但我们并没有推荐具体的药物和/或机械装置。我们建议,行择期髋膝关节置换术的患者术后应进行早期活动。采用椎管内麻醉有助于减少失血,但没有发现椎管内麻醉会影响VTED发生的证据。目前也没有明确的证据表明对有药物预防禁忌和/或已知VTED的患者使用下腔静脉过滤器能防止肺栓塞的发生。 展开更多
关键词 关节成形术 置换 假体选择 研究进展
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Hepatic angiotensin-converting enzyme 2 expression in metabolic dysfunction-associated steatotic liver disease and in patients with fatal COVID-19
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作者 Angus K jacobs Steven D Morley +7 位作者 Kay Samuel Katie Morgan Lyndsey Boswell Timothy J Kendall David A Dorward Jonathan A Fallowfield Peter C Hayes John N Plevris 《World Journal of Gastroenterology》 SCIE CAS 2024年第31期3705-3716,共12页
BACKGROUND Metabolic dysfunction-associated steatotic liver disease(MASLD),characterised by hepatic lipid accumulation,causes inflammation and oxidative stress accompanied by cell damage and fibrosis.Liver injury(LI)i... BACKGROUND Metabolic dysfunction-associated steatotic liver disease(MASLD),characterised by hepatic lipid accumulation,causes inflammation and oxidative stress accompanied by cell damage and fibrosis.Liver injury(LI)is also frequently reported in patients hospitalised with coronavirus disease 2019(COVID-19),while preexisting MASLD increases the risk of LI and the development of COVID-19-associated cholangiopathy.Mechanisms of injury at the cellular level remain unclear,but it may be significant that severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)which causes COVID-19,uses angiotensin-converting expression enzyme 2(ACE2),a key regulator of the‘anti-inflammatory’arm of the renin-angiotensin system,for viral attachment and host cell invasion.AIM To determine if hepatic ACE2 levels are altered during progression of MASLD and in patients who died with severe COVID-19.METHODS ACE2 protein levels and localisation,and histological fibrosis and lipid droplet accumulation as markers of MASLD were determined in formalin-fixed liver tissue sections across the MASLD pathological spectrum(isolated hepatocellular steatosis,metabolic dysfunction-associated steatohepatitis(MASH)+/-fibrosis,end-stage cirrhosis)and in post-mortem tissues from patients who had died with severe COVID-19,using ACE2 immunohistochemistry and haematoxylin and eosin and picrosirius red staining of total collagen and lipid droplet areas,followed by quantification using machine learning-based image pixel classifiers.RESULTS ACE2 staining is primarily intracellular and concentrated in the cytoplasm of centrilobular hepatocytes and apical membranes of bile duct cholangiocytes.Strikingly,ACE2 protein levels are elevated in non-fibrotic MASH compared to healthy controls but not in the progression to MASH with fibrosis and in cirrhosis.ACE2 protein levels and histological fibrosis are not associated,but ACE2 and liver lipid droplet content are significantly correlated across the MASLD spectrum.Hepatic ACE2 levels are also increased in COVID-19 pa 展开更多
关键词 Metabolic dysfunction-associated steatotic liver disease Angiotensin-converting enzyme 2 IMMUNOHISTOCHEMISTRY COVID-19 COVID-19-associated cholangiopathy
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CD4^(+)T cells produce IFN-I to license cDC1s for induction of cytotoxic T-cell activity in human tumors
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作者 Xin Lei Daniël C.de Groot +13 位作者 Marij J.P.Welters Tom de Wit Ellen Schrama Hans van Eenennaam Saskia J.Santegoets Timo Oosenbrug Annemarthe van der Veen Joris L.Vos Charlotte L.Zuur Noel F.C.C.de Miranda Heinz jacobs Sjoerd H.van der Burg Jannie Borst Yanling Xiao 《Cellular & Molecular Immunology》 SCIE CAS CSCD 2024年第4期374-392,共19页
CD4^(+)T cells can"help"or"license" conventional type 1 dendritic cells(cDC1s)to induce CD8^(+)cytotoxic T lymphocyte(CTL)anticancer responses,as proven in mouse models.We recently identified cDC1s... CD4^(+)T cells can"help"or"license" conventional type 1 dendritic cells(cDC1s)to induce CD8^(+)cytotoxic T lymphocyte(CTL)anticancer responses,as proven in mouse models.We recently identified cDC1s with a transcriptomic imprint of CD4^(+)T-cell help,specifically in T-cell-infiltrated human cancers,and these cells were associated with a good prognosis and response to PD-1-targeting immunotherapy.Here,we delineate the mechanism of cDC1 licensing by CD4^(+)T cells in humans.Activated CD4^(+)T cells produce IFNβvia the STING pathway,which promotes MHC-I antigen(cross-)presentation by cDC1s and thereby improves their ability to induce CTL anticancer responses.In cooperation with CD40 ligand(L),IFNβalso optimizes the costimulatory and other functions of cDC1s required for CTL response induction.IFN-I-producing CD4^(+)T cells are present in diverse T-cell-infiltrated cancers and likely deliver“help”signals to CTLs locally,according to their transcriptomic profile and colocalization with“helped/licensed”cDCs and tumor-reactive CD8^(+)T cells.In agreement with this scenario,the presence of IFN-I-producing CD4^(+)T cells in the TME is associated with overall survival and the response to PD-1 checkpoint blockade in cancer patients. 展开更多
关键词 CD4^(+)T-cell help cDC1 licensing IFN-I signaling CD40 costimulation (cross-)presentation CTL priming Tumor control
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设计酚类抗氧剂保护润滑油的技术 被引量:3
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作者 Tom Tang Gertrude jacobs 《润滑油》 CAS 2020年第4期33-39,共7页
抗氧剂是润滑油配方中的关键成分,通过有效地牺牲自身来保护润滑系统,即清除润滑油在使用过程中产生的自由基或分解氧化过程中形成的过氧化物,且抗氧剂在抗氧化反应中所产生的副产物不会对润滑体系造成不可控伤害。3,5-二叔丁基-4-轻基... 抗氧剂是润滑油配方中的关键成分,通过有效地牺牲自身来保护润滑系统,即清除润滑油在使用过程中产生的自由基或分解氧化过程中形成的过氧化物,且抗氧剂在抗氧化反应中所产生的副产物不会对润滑体系造成不可控伤害。3,5-二叔丁基-4-轻基苯基丙酸酯(HPP)是位阻酚类抗氧剂的关键分子结构。在HPP衍生物中发现含有C8~C15烷基的化合物是理想的润滑油抗氧剂,如室温下是液态,非常便于在调配润滑油时使用,耐高温性能优异,且在各种试验条件下具有高效的抗氧化性能。抗氧剂和润滑油中其他成分的协同效应是理想商用抗氧剂的一种特性。二苯胺类抗氧剂和二硫代磷酸锌是两种常见的润滑油成分。在抗氧剂的评估过程中观察到,酚类抗氧剂与二苯胺类抗氧剂、二硫代磷酸锌均有显著的协同抗氧化作用,因为二硫代磷酸锌容易形成积炭而破坏汽车的催化转换器,润滑油工业界都在限制它的使用量。在积炭实验中发现,优化酚类氧化剂与二硫代磷酸锌的配比不仅可以减少二硫代磷酸锌的使用量,而且在最大限度减少积炭形成的同时显著提高润滑油抗氧化性能。 展开更多
关键词 酚类抗氧剂 协同效应 润滑油
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Intrahepatic distribution of hepatitis B virus antigens in patients with and without hepatocellular carcinoma 被引量:5
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作者 Parham Safaie Mugilan Poongkunran +5 位作者 Ping-Ping Kuang Asad Javaid Carl jacobs Rebecca Pohlmann Imad Nasser Daryl TY Lau 《World Journal of Gastroenterology》 SCIE CAS 2016年第12期3404-3411,共8页
AIM: To study the intrahepatic expression of hepatitis B surface antigen (HBsAg) and hepatitis B core antigen (HBcAg) in chronic hepatitis B patients with and without hepatocellular carcinoma.METHODS: A total of 33 ch... AIM: To study the intrahepatic expression of hepatitis B surface antigen (HBsAg) and hepatitis B core antigen (HBcAg) in chronic hepatitis B patients with and without hepatocellular carcinoma.METHODS: A total of 33 chronic hepatitis B patients (mean age of 40.3 &#x000b1; 2.5 years), comprising of 14 HBeAg positive and 19 HBeAg negative patients; and 13 patients with hepatitis B virus related hepatocellular carcinoma (mean age of 49.6 &#x000b1; 4.7 years), were included in our study. Immunohistochemical staining for HBcAg and HBsAg was done using standard streptavidin-biotin-immunoperoxidase technique on paraffin-embedded liver biopsies. The HBcAg and HBsAg staining distributions and patterns were described according to a modified classification system.RESULTS: Compared to the HBeAg negative patients, the HBeAg positive patients were younger, had higher mean HBV DNA and alanine transaminases levels. All the HBeAg positive patients had intrahepatic HBcAg staining; predominantly with &#x0201c;diffuse&#x0201d; distribution (79%) and &#x0201c;mixed cytoplasmic/nuclear&#x0201d; pattern (79%). In comparison, only 5% of the HBeAg-negative patients had intrahepatic HBcAg staining. However, the intrahepatic HBsAg staining has wider distribution among the HBeAg negative patients, namely; majority of the HBeAg negative cases had &#x0201c;patchy&#x0201d; HBsAg distribution compared to &#x0201c;rare&#x0201d; distribution among the HBeAg positive cases. All but one patient with HCC were HBeAg negative with either undetectable HBV DNA or very low level of viremia. Intrahepatic HBcAg and HBsAg were seen in 13 (100%) and 10 (77%) of the HCC patients respectively. Interestingly, among the 9 HCC patients on anti-viral therapy with suppressed HBV DNA, HBcAg and HBsAg were detected in tumor tissues but not the adjacent liver in 4 (44%) and 1 (11%) patient respectively.CONCLUSION: Isolated intrahepatic HBcAg and HBsAg can be present in tumors of patients with suppressed HBV DNA on antiviral therapy; that may predispose them to cancer d 展开更多
关键词 Hepatitis B virus Chronic hepatitis B Hepatocellular carcinoma Hepatitis B core antigen Hepatitis B surface antigen
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Development of cork oak (Quercus suber L.) seedlings in response to tree shelters and mulching in northwestern Tunisia 被引量:5
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作者 Taher Mechergui Marta Pardos +2 位作者 Naceur Boussaidi Brahim Hasnaoui Douglass F. jacobs 《Journal of Forestry Research》 SCIE CAS CSCD 2013年第2期193-204,共12页
The need for reforestation in cork oak (Quercus suber L.) areas is challenged by difficulties. Principal among these is herbivory of young plants, vegetative competition, and slow growth rates of cork oak seedlings.... The need for reforestation in cork oak (Quercus suber L.) areas is challenged by difficulties. Principal among these is herbivory of young plants, vegetative competition, and slow growth rates of cork oak seedlings. We evaluated the early development of cork oak seedlings treated using tree shelters and mulching in northwestern Tunisia. We tested three tree shelter treatments (non-vented, vented, and control) to shield seedlings from animal damage and five mulch types to control competing vegetation (Italian Stone Pine, Lentisk, combination of Italian Stone Pine and Lentisk (organic mulches), gravel (inorganic mulch) and no mulch). At the end of the two-year experiment, sheltered seedlings were 89-99% taller than unshelteredseedlings and had higher numbers and lengths of shoot growth flushes. In contrast, both stem diameter growth and dry weight biomass (from samples extracted after two years) were significantly reduced inside tree shelters. Root-to-shoot ratio was not significantly different in sheltered vs. unsheltered seedlings, suggesting that tree shelters do not adversely affect this parameter. Mulching alone did not favour growth, but could be beneficial when combined with tree shelters. The combination of vented tree shelters and gravel mulch was the most effective treatment for promoting diameter, height and stem volume growth. 展开更多
关键词 Quercus suber L. AFFORESTATION tree shelter MULCHING seedling growth polycyclism
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