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Wear Behavior of a Bio-inspired Bearing for off-center Loads

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Journal of Bionic Engineering 2020年第6期17卷 1251-1262页

作者： Delphine Sysaykeo Jean-marc Linares Emmanuel Mermoz Alix-Marseile Universite CNRSCentre National de la Recherche ScientifiqueISMInstitut des Sciences du MouvementMarseille 13009France Advanced concepts and Dynamic systems architecture department Airbus HelicoptersAeroport International Marseille ProvenceMarignane 13700France

Misalignment is one of the most common causes of wear in bush *** improvements have been proposed by many ***,it did not efficiently reduce the *** geometrical designs sometimes reach their *** this reason,a bio-inspired design is proposed to solve the *** this article,a bio-inspired bearing suited to misalignment was tested and compared to a classical bush *** contact pressures of both bearings were compared with static Finite Element(FE)simulations for off-center *** to the complex shape of the involved contact,the performances of both bearings were also studied over *** wear behaviors were predicted with a numerical *** methodologies emplaced to simulate the wear were described in this ***,the wear coefficient determination obtained by experimental testing was *** pressure value,the contact zone and the wear depth were compared and *** wear results for the classical bearing are in accordance with the *** simulations show a deeper wear on the classical bush bearing than on the bio-inspired *** leads to a longer period of service life for the bio-inspired bearing.

关键词： biologically inspired design bush bearing wear simulation

When is a varicocele repair indicated： the dilemma of hypogonadism and erectile dysfunction？

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Asian Journal of Andrology 2016年第2期18卷 213-216,J0004页

作者： Ali A Dabaja marc Goldstein Department of Male Reproductive Medicine Weill Cornell Medical College New York USA Department of Urology Henry Ford Health System Detroit MI USA.

In the past, the indications for varicocelectomy are primarily for infertility with abnormal semen parameters, testicular hypotrophy/atrophy in adolescents, and/or pain. The surgical treatment of varicocele for hypogonadism is controversial and debated. Recently, multiple reports in the literature have suggested that varicocele is associated with hypogonadism and varicocele repair can increase testosterone levels. Men with hypogonadal symptoms should have at least two serum testosterone levels. Microsurgical varicocelectomy may be beneficial for men with clinically palpable varicoceles with documented hypogonadism. In this review, we summarize the most recent literature linking varicocele to hypogonadism and sexual dysfunction and the impact of repair on serum testosterone levels. We performed a search of the published English literature. The key words used were ＂varicocele and hypogonadism＂ and ＂varicocele surgery and testosterone.＂ We included published studies after 1998. We, also, evaluated the effect of surgery on the changes in the serum testosterone level regardless of the indication for the varicocele repair.

关键词： erectile dysfunction hypogonadism varicocele varicocelectomy

Microsurgical varicocelectomy： a review

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Asian Journal of Andrology 2013年第1期15卷 56-60页

作者： Akanksha Mehta marc Goldstein Department of Urology and Center for Male Reproductive Medicine and Surgery Weill Cornell Medical College New York NY 10021 USA

Varicocelectomy is the most commonly performed surgical procedure for the treatment of male infertility. Although several different techniques for varicocele repair have been described in the literature, microsurgical varicocelectomy performed through a subinguinal or inguinal incision is recognized as the gold-standard approach for varicocelectomy, due to high success rates with minimal complications. Standard indications for varicocelectomy include palpable varicocele（s）, with one or more abnormal semen parameters, and, for the couple trying to conceive, in the setting of normal or correctable female infertility. However, varicocele repair is often recommended and undertaken for reasons other than infertility, including low serum testosterone, testicular pain, testicular hypotrophy and poor sperm DNA quality. This article reviews the technical aspects of microsurgical varicocelectomy, and its indications in adults and adolescents.

关键词： DNA fragmentation hypogonadism infertility microsurgical varicocelectomy orchalgia varicocele repair

Role of endoscopy in predicting the disease course in inflammatory bowel disease

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World Journal of Gastroenterology 2010年第21期16卷 2626-2632页

作者： Matthieu Allez marc Lémann Department of Gastroenterology and Equipe AVENIR INSERM Saint-Louis HospitalAPHPUniversité Denis Diderot Paris 775010 ParisFrance

Endoscopy provides a direct evaluation of mucosal lesions in inflammatory bowel disease(IBD),permitting the description of elementary lesions,their surface extent and *** severity of mucosal lesions directly reflects disease activity and may help to identify an aggressive behavior of the *** studies have recently pointed out the potential role of endoscopy in the prediction of IBD ***,severe endoscopic lesions in Crohn's disease(CD) patients,defined by deep and extensive ulcerations on at least one part of the colon,are associated with an increased risk of penetrating complication and *** endoscopic lesions during severe attacks of ulcerative colitis(UC) are associated with an increased risk of colectomy in the short and long *** of postoperative recurrence in CD may help to predict the risk of clinical relapse and need for further *** of mucosal healing,which can be obtained by administration of several types of drugs,is associated with a better outcome,less surgery and *** review focuses on the assessment of endoscopic severity in CD and UC and on the impact of endoscopic severity on disease *** specifically,we discuss how endoscopy can be used at different stages of IBD to predict the disease course and/or to adapt treatment strategies.

关键词： Crohn’s disease Ulcerative colitis Inflammatory bowel disease Colonoscopy Natural history Outcome Medical therapy Surgery

Development of Caenorhabditis elegans pharynx,with emphasis on its nervous system

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Acta Pharmacologica Sinica 2005年第4期26卷 396-404页

作者： marc PILON Catarina M RCK Lundberg Laboratory Chalmers University G teborg S-405 30 Sweden Lundberg Laboratory Chalmers University G teborg S-405 30 Sweden

The Caenorhabditis elegans pharynx is a neuromuscular tube of which the func-tion is to pump and crush bacteria,and inject them into the *** 80-cellpharynx develops via the morphogenesis and differentiation of the ceils that com-pose its semi-spherical primordiurn,and requires the activity of several evolution-arily conserved genes,such as pha-4 (the homolog to the Drosophilaforkheadand vertebrate FoxA),ceh-22 (the homolog to the Drosophila tinman and verte-brate Nkx2.5),and pha-2 (the homolog to the vertebrate Hex).There are 20 neu-rons in the pharynx,each with a reproducible unique *** analysis of axon guidance in the pharynx indicates that some axon trajec-tories are in part established without growth cones,whereas other parts necessi-tate growth cone function and *** we provide an overview of thedevelopmental genetics of the Caenorhabditis elegans pharynx,with an empha-sis on its nervous system.

关键词： Caenorhabditis elegans pharynx axon growth cones morphogenesis heart

Delineating the respective impacts of stochastic curl- and grad-forces in a family of idealized core genetic commitment circuits

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Frontiers of Electrical and Electronic Engineering in China 2016年第2期4卷 69-83页

作者： marc Turcotte Department of Mathematics The University of Texas at Arlington Arlington TX 76109 USA Biological Sciences The University of Texas at Dallas Richardson TX-75080 USA

Stochastic dynamics pervades gene regulation. Despite being random, the dynamics displays a kind of innate structure. In fact, two stochastic forces combine driving efforts： one force originates from the gradient of the underlying stochastic potential, and the other originates from the mathematical curl of the probability flux. The curl force gives rise to rotation. The gradient force gives rise to drift. Together they give rise to helical behavior. Here, it is shown that around and about the vicinity of attractive fixed points, the gradient force naturally wanes but the curl force is found to remain high. This leads to a locally noticeably different type of stochastic track near and about attractive fixed points, compared to tracks in regions where drift dominates. The consistency of this observation with the experimental fact that, in biology, fate commitment appears to not be a-priory locked-in, but rather necessitating active maintenance, is discussed. Hence attractive fixed-points are not only fuzzy, but may effectively be, locally, ＂more free＂.

关键词： systems biology theoretical biology gene regulation nonlinear dynamics stochasticity

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Endoscopic resection of superficial gastrointestinal tumors

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World Journal of Gastroenterology 2008年第29期14卷 4600-4606页

作者： Giovannini marc Cesar Vivian Lopes Endoscopic Unit Paoli-Calmettes Institute232 Bd St-Marguerite Cedex 13273 France

Therapeutic endoscopy plays a major role in the management of gastrointestinal (GI) neoplasia. Its indications can be generalized into four broad categories; to remove or obliterate neoplastic lesion, to palliate malignant obstruction, or to treat bleeding. Only endoscopic resection allows complete histological staging of the cancer, which is critical as it allows stratification and refinement for further treatment. Although other endoscopic techniques, such as ablation therapy, may also cure early GI cancer, they can not provide a definitive pathological specimen. Early stage lesions reveal low frequency of lymph node metastasis which allows for less invasive treatments and thereby improving the quality of life when compared to surgery. Endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) are now accepted worldwide as treatment modalities for early cancers of the GI tract.

关键词： Superficial gastrointestinal cancers Endoscopic mucosal resection Endoscopic submucosaldissection Lymph node spreading Esophagus Stomach Colorectal

Management of Mandibular Fractures in Children in Ivory Coast: Experience of the Stomatology and Maxillofacial Surgery Department at the University Hospital of Cocody from 2000 to 2019

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Open Journal of Stomatology 2024年第7期14卷 341-349页

作者： Bakary Ouattara Camille Assouan Laurent Boka Koffi Konan René Kouakou Ake Lucien Jonathan Yapo Annick Zoglo-Bro Ahi Morel Mounin Chapo Affoué Linda Marie Pierre Koffi Kahder Morel Diarra Atse Kobo N’Guessan Konan marc Koffi Department of Stomatology Maxillofacial Surgery University Flix Houphout-Boigny Abidjan Republic of Ivory Coast Department of Oral Pathology University Flix Houphout-Boigny Abidjan Republic of Ivory Coast

Introduction: Mandibular fractures in children are becoming increasingly common. Treatment of these fractures is difficult due to their anatomical and physiological complexity. Therefore, there is a need for well-codified management. Our main aim was to develop a decision algorithm for the management of mandibular fractures in children based on our experience. Materials and Methods: This was a retrospective descriptive study carried out in the Department of Stomatology and Maxillofacial Surgery at the University Hospital of Cocody over a period of 20 years (2000-2019). Results: We enrolled 58 patients. The mean age of the patients was 9.35 ± 2.3 years with a sex ratio of 2.22. Traffic accidents were the main cause of mandibular fractures (60.35%). Condylar fractures were the most common (46.87%). Treatment was orthopedic in 45.76% of cases, mixed (orthopedic and surgical) in 24.14% and surgical in 5.17%. Patients were followed up weekly for 1 month, then monthly for 6 months and annually for 3 years, with panoramic radiographs of the maxilla starting at 21 days. We observed 2 cases of complications: temporomandibular ankylosis and gingival stomatitis. Conclusion: Mandibular fractures are common in children. Management is difficult due to anatomical and physiological peculiarities. The choice of treatment depends on several criteria.

关键词： Fractures Mandible Children Treatment Ivory Coast

Phase coexistence properties of liquid mercury:a simulation study

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Rare Metals 2006年第5期25卷 567-571页

作者： Jean-Louis Bretonnet Jean-marc Bomont Laboratoire de Physique des Milieux Denses Université Paul Verlaine1bd F.D.Arago57078 MetzCedex 3France

The thermophysical properties of expanded liquid mercury have been investigated along the liquid-vapor coexistence curve by using Monte Carlo and Molecular Dynamic simulations. For the purpose, an empirical state dependent interatomic potential for the region of dense metallic liquid is used, while the state dependence is not necessary near the cliffcal point. In order to test the validity of this potential, we determine the surface layering and the sound velocity, two properties very sensitive to the choice of the potential. Our results are in quite good agreement with other theoretical results and to the experimental data available in the literature.

关键词： mercury simulation phase coexistence liquid state

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