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Computation of flow through the oesophagogastric junction

World Journal of Gastroenterology 2007年第9期13卷 1360-1364页

作者： barry P McMahon Karl D Odie Kenneth W Moloney Hans Gregersen Department of Medical Physics and Clinical Engineering Adelaide and Meath Hospital Dublin Incorporating the National Children’s Hospital Tallaght Dublin 24Ireland IMed Centre Department of Mechanical Engineering Institute of Technology Tallaght Dublin 24 Ireland Center for Visceral Biomechanics and Pain Aalborg Hospital Aalborg DK-9100 DenmarkIMed Centre Institute of Technology Tallaght Dublin 24 Ireland

Whilst methods exist to indirectly measure the effects of increased flow or gastro-oesophageal refluxing, they cannot quantitatively measure the amount of acid travelling back up into the oesophagus during reflux, nor can they indicate the flow rate through the oesophagogastric junction (OGJ). Since OGJ dysfunction affects flow it seems most appropriate to describe the geometry of the OGJ and its effect on the flow. A device known as the functional lumen imaging probe (FLIP) has been shown to reliably measure the geometry of and pressure changes in the OGJ. FLIP cannot directly measure flow but the data gathered from the probe can be used to model flow through the junction by using computational flow dynamics (CFD). CFD uses a set of equations known as the Navier-Stokes equations to predict flow patterns and is a technique widely used in engineering. These equations are complex and require appropriate assumptions to provide simplifications before useful data can be obtained. With the assumption that the cross-sectional areas obtained via FLIP are circular, the radii of these circles can be obtained. A cubic interpolation scheme can then be applied to give a high-resolution geometry for the OGJ. In the case of modelling a reflux scenario, it can be seen that at the narrowest section a jet of fluid squirts into the oesophagus at a higher velocity than the fluid surrounding it. This jet has a maximum velocity of almost 2 ms-1 that occurs where the OGJ is at its narrowest. This simple prediction of acid ‘squirting’ into the oesophagusillustrates how the use of numerical methods can be used to develop a better understanding of the OGJ. This initial work using CFD shows some considerable promise for the future.

关键词： Computational flow dynamics model Oesophagus

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Glyoxylate reductase Isoform 1 is Localized in the Cytosol and Not Peroxisomes in Plant Cells

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Journal of Integrative Plant Biology 2012年第3期54卷 152-168页

作者： Steven L. K. Ching Satinder K. Gidda Amanda rochon Owen r. van Cauwenberghe barry J. Shelp robert T. Mullen Department of Molecular and Cellular Biology University of Guelph Guelph Ontario N1G 2W1 Canada Department of Plant Agriculture University of Guelph Guelph Ontario N1G 2W1 Canada

Glyoxylate reductase （GLYr） is a key enzyme in plant metabolism which catalyzes the detoxification of both photorespiratory glyoxylate and succinic semialdehdye, an intermediate of the γ-aminobutyrate （GABA） pathway. Two isoforms of GLYr exist in plants, GLYr1 and GLYr2, and while GLYr2 is known to be localized in plastids, GLYr1 has been reported to be localized in either peroxisomes or the cytosol. Here, we reappraised the intracellular localization of GLYr1 in Arabidopsis thaliana L. Heynh （ecotype Lansberg erecta） using both transiently-transformed suspension cells and stably-transformed plants, in combination with fluorescence microscopy. The results indicate that GLYr1 is localized exclusively to the cytosol regardless of the species, tissue and/or cell type, or exposure of plants to environmental stresses that would increase flux through the GABA pathway. Moreover, the C-terminal tripeptide sequence of GLYr1, -SrE, despite its resemblance to a type 1 peroxisomal targeting signal, is not sufficient for targeting to peroxisomes. Collectively, these results define the cytosol as the intracellular location of GLYr1 and provide not only important insight to the metabolic roles of GLYr1 and the compartmentation of the GABA and photorespiratory pathways in plant cells, but also serve as a useful reference for future studies of proteins proposed to be localized to peroxisomes and/or the cytosol.

关键词： Arabidopsis GABA GLYr1 cytosol photobleaching peroxisome PTS stress tobacco BY-2.

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Early microrecanalization of vas deferens following biodegradable graft implantation in bilaterally vasectomized rats

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Asian Journal of Andrology 2009年第3期11卷 373-378页

作者： Christopher M. Simons barry r. De Young Thomas S. Griffith Timothy L. ratliff Erin Jones Surya K. Mallapragada Moshe Wald Department of Urology University of Iowa Iowa City IA 52242-1089 USA Department of Pathology University of Iowa Iowa City IA 52242-1089 USA Department of Chemical and Biological Engineering Iowa State University Ames IA USA

We evaluated a biodegradable graft for reconstruction of rat vasa deferentia with long obstructed or missing segments. A total of 47 Sprague-Dawley rats underwent bilateral vasectomy and were divided into groups according to length of the vas deferens affected （0.5, 1, 1.5 cm）. After 8 weeks, poly-（D,L-lactide）（PDLA） grafts were used to reconnect the vas deferens, Grafts and adjoining vasa deferentia were excised 8 and 12 weeks later and evaluated microscopically. At 8 weeks, microscopic changes included a robust inflammatory response around the grafts. All grafts were still intact but in the early stages of degradation. No microtubules, indicative of vas deferens recanalization, were identified. One specimen showed evidence of healing and neovascularization at the interface zone between the vas deferens and the graft. At 12 weeks, grafts were further degraded but still present. Microscopic evaluation showed decreased inflammation. Seven specimens showed neovascularization at the interface zone; two of these showed distinct epithelialized vas deferens microcanals at the graft edges. One specimen showed a microcanal spanning the entire 0.5-cm graft. A time period of 8 weeks is not ample enough for vas deferens regeneration in the setting of a biodegradable PDLA graft; however, early evidence of re-growth was seen at 12 weeks. A longer healing time should permit further biodegradation of the graft, as well as re-growth and possible eventual reconnection of the vas deferens, allowing passage of sperm. These findings suggest a potential role for biodegradable grafts in the reconstruction ofvas deferens with long obstructed segments.

关键词： graft infertility male vas deferens

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The elements of social theory

The elements of social theory

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作者： barry Barnes.

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Microstructural homogeneity and mechanical behavior of a selective laser melted Ti-35Nb alloy produced from an elemental powder mixture

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Journal of Materials Science & Technology 2021年第2期61卷 221-233页

作者： Jincheng Wang Yujing Liu Chirag Dhirajlal rabadia Shun-Xing Liang Timothy barry Sercombe Lai-Chang Zhang School of Engineering Edith Cowan University270Joondalup DriveJoondalupPerthWA 6027Australia School of Engineering M050The University of Western Australia35 Stirling HighwayCrawleyPerthWA 6009Australia

Although using elemental powder mixtures may provide broad alloy selection at low cost for selective laser melting(SLM), there is still a concern on the resultant microstructural and chemical homogeneity of the produced parts. Hence, this work investigates the microstructure and mechanical properties of a SLM-produced Ti-35 Nb composite(in wt%) using elemental powder. The microstructural characteristics including ? phase, undissolved Nb particles and chemical homogeneity were detailed *** revealed the presence of relatively soft undissolved Nb particles and weak interface bonding around Nb-rich regions in as-SLMed samples. Solid-solution treatment can not only improve chemical homogeneity but also enhance bonding through grain boundary strengthening, resulting in43 % increase in tensile elongation for the heat-treated Ti-35 Nb compared to the as-SLMed counterpart. The analyses of tensile fractures and shear bands further confirmed the correlation between the different phases and the ductility of Ti-35 Nb. In particular, the weak bonding between undissolved Nb and the matrix in the as-SLMed sample reduces its ductility while the ? grains in solid-solution treated Ti-Nb alloy can induce a relatively stable plastic flow therefore better ductility. This work sheds insight into the understanding of homogenization of microstructure and phases of SLM-produced alloys from an elemental powder mixture.

关键词： Titanium-niobium Selective laser melting Microstructure Nanoindentation Mechanical behavior

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A preliminary study of sperm identification in microdissection testicular sperm extraction samples with deep convolutional neural networks

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Asian Journal of Andrology 2021年第2期23卷 135-139页

作者： Daniel J Wu Odgerel Badamjav Vikrant V reddy Michael Eisenberg barry Behr Department of Computer Science Stanford UniversityStanfordCA 94305USA Department of Urology University of Utah HealthSalt Lake CityUT 84108USA Department of Obstetrics and Gynecology Stanford Children’s HealthStanfordCA 94305USA Department of Urology Stanford University School of MedicineStanfordCA 94305USA

Sperm identification and selection is an essential task when processing human testicular samples for in vitro *** and identifying sperm cell(s)in human testicular biopsy samples is labor intensive and time *** developed a new computer-aided sperm analysis(CASA)system,which utilizes deep learning for near human-level performance on testicular sperm extraction(TESE),trained on a custom *** system automates the identification of sperm in testicular biopsy samples.A dataset of 702 de-identified images from testicular biopsy samples of 30 patients was *** image was normalized and passed through glare filters and diffraction *** data were split 80%,10%,and 10%into training,validation,and test sets,***,a deep object detection network,composed of a feature extraction network and object detection network,was trained on this *** model was benchmarked against embryologists’performance on the detection *** deep learning CASA system achieved a mean average precision(mAP)of 0.741,with an average recall(Ar)of 0.376 on our *** proposed method can work in real time;its speed is effectively limited only by the imaging speed of the *** results indicate that deep learning-based technologies can improve the efficiency of finding sperm in testicular biopsy samples.

关键词： artificial intelligence computer vision male infertility microdissection testicular sperm extraction sperm

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β-defensins and the epididymis： contrasting influences of prenatal, postnatal, and adult scenarios

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Asian Journal of Andrology 2016年第2期18卷 323-328,J0008页

作者： Camilla M ribeiro Erick Jr Silva barry T Hinton Maria Christina W Avellar Section of Experime.ntaI.Endocrinology Department of Pharmacology Universidade Federal de Sao Paulo - Escola Paulista de Medicina Sao Paulo Brazil Department of Cell Biology University of Virginia School of Medicine Charlottesville Virginia USA Present address: Department of Pharmacology Institute Of Biosciences of BotucatuUniversidade Estadual Paulista 'Julio de Mesquita Filho' Botucatu Sao Paulo 186).8-970 Brazil.

β-defensins are components of host defense, with antimicrobial and pleiotropic immuno-modulatory properties. research over the last 15 years has demonstrated abundant expression of a variety of β-defensins in the postnatal epididymis of different species. A gradient of region- and cell-specific expression of these proteins is observed in the epithelium of the postnatal epididymis. Their secretion into the luminal fluid and binding to spermatozoa as they travel along the epididymis has suggested their involvement in reproduction-specific tasks. Therefore, continuous attention has been given to various β-defensins for their role in sperm function and fertility. Although β-defensins are largely dependent on androgens, the underlying mechanisms regulating their expression and function in the epididymis are not well understood. recent investigation has pointed out to a new and interesting scenario where β-defensins emerge with a different expression pattern in the Wolffian duct, the embryonic precursor of the epididymis, as opposed to the adult epididymis, thereby redefining the concept concerning the multifunctional roles of β-defensins in the developing epididymis. In this review, we summarize some current views of β-defensins in the epididymis highlighting our most recent data and speculations on their role in the developing epididymis during the prenatal-to-postnatal transition, bringing attention to the many unanswered questions in this research area that may contribute to a better understanding of epididymal biology and male fertility.

关键词： androgens embryogenesis epididymis organogenesis β-defensins

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New models to study vulvodynia: hyperinnervation and nociceptor sensitization in the female genital tract

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Neural regeneration research 2018年第12期13卷 2096-2097页

作者： Christine M.barry Kalyani K.Huilgol rainer V.Haberberger Anatomy and Histology College of Medicine and Public Health Flinders University Centre for Neuroscience Flinders University

Vulvodynia is a prevalent form of chronic pain, most com- monly affecting the vaginal vestibule （vestibulodynia）（Pukall et al., 2016）. Women with vulvodynia describe intense pain in response to light touch of the affected region, such that sexual function and other activities can be severely limited. Medical costs associated with vulvodynia are high, exceeding $21 billion annually in the United States （Xie et al., 2012）. The high level of direct medical costs has been linked to high treatment failure rates. Many women with the disorder consult multiple practitioners and undergo multiple courses of treatment with limited benefit.

关键词： New models to study vulvodynia hyperinnervation and nociceptor sensitization in the female genital tract CFA

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Explaining patterns of species dominance in the shrub steppe systems of the Junggar Basin(China) and Great Basin(USA)

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Journal of Arid Land 2013年第4期5卷 415-427页

作者： Wendy TrOWBrIDGE Thomas ALBrIGHT Scot FErGUSON Jun LI barry PErrYMAN robert S NOWAK Department of Natural resources & Environmental Science University of Nevada RenoReno NV 89557USA Department of Geography University of Nevada RenoReno NV 89557USA Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Department of Agriculture Nutrition and Veterinary Sciences1664 N Virginia StreetMail Stop 202University of Nevada RenoReno NV 89557USA

Natural scientists have long recognized that regions with similar climate tend to have similar *** observations suggest that shrub steppe communities of the western US and western China may be two such regions with similar annual precipitation,temperature,land use,and *** cold dry shrub steppes have traditionally been *** these similarities,patterns of species dominance are *** species that are rare in China become dominant when introduced to the United *** objective of this study was to investigate how climate,land use and community structure may explain these patterns of species *** structure and grazing intensity were measured at 5 sites in each *** information was combined with a broader review of the literature describing the history of grazing in both *** was analyzed based on a spatially-gridded,interpolated weather time series （monthly records） and climatological summary （1961-1990 mean conditions） data set from the Climate research *** found that differences in summer precipitation and winter minimum temperature,land use intensity,and shrub size may all contribute to the dominance of annual species in the Great Basin,particularly Bromus *** particular,previous work indicates that summer precipitation and winter temperature drive the distribution of Bromus tectorum in the Great *** a result,sites with wet summers and cold springs,similar to the Chinese sites,would not be expected to be dominated by Bromus tectorum.A history of more intense grazing of the Chinese sites,as described in the literature,also is likely to decrease fire frequency,and decreases litter and shrub dominance,all of which have been demonstrated to be important in Bromus tectorum establishment and ultimate *** research is necessary to determine if other annuals that follow the same pattern of scarcity in the Junggar Basin and dominance in the Great Basin are res

关键词： climate community ecology convergent evolution Bromus tectorum shrub steppe Junggar Basin Great Basin

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Second generation biorefining in Ecuador:Circular bioeconomy,zero waste technology,environment and sustainable development:The nexus

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Journal of Bioresources and Bioproducts 2021年第2期6卷 83-107页

作者： Lourdes M.Orejuela-Escobar Andrea C.Landázuri barry Goodell Universidad San Francisco de Quito USFQ Colegio de Ciencias e IngenieríasInstituto de Ingeniería CircularEngineeringApplied Sciences&Simulation Group(GICAS)Chemical Engineering DepartmentDiego de Robles y Vía InteroceánicaP.O.Box 17-0901QuitoEcuador Universidad San Francisco de Quito USFQ Instituto de Investigaciones Biológicas y Ambientales BIÓSFERADiego de Robles y Vía InteroceánicaP.O.Box 17-0901QuitoEcuador University of Massachusetts Department of MicrobiologyAmherstMA 01003United States

The projection of world population growth with concurrent generation of large volumes of agroindustrial waste that negatively affect the environment is of great ***,this review article describes the nexus between concepts of Circular Bioeconomy,Zero Waste Technology,Sustainable Development,Biorefineries,and alternatives and research efforts to generate less environmental impact.A brief analysis of the Ecuadorian industry and exports is described,emphasizing the fact that,to improve the Ecuadorian trade balance,it is necessary to increase industrial *** is important to have emerging technologies and innovation in order to promote the replacement of fossil-derived raw materials with renewable raw materials and develop more environmentally friendly processes and *** paper analyses the state of biomass research and its transformation in Ecuador,together with current pretreatment research on biomass to obtain bioproducts and biofuels in a biorefinery that promotes clean production for the extraction of phytochemicals using green solvents,such as deep eutectic solvents;and technologies to recover high-value added materials with enhanced *** conclusion,the need to develop technologies and markets to commercialize high value-added products coming from biorefineries is highlighted,as this will increase the income both in rural and urban areas and will strengthen the productivity and profitability of the Ecuadorian *** goal through this analysis is to improve Ecuador’s trade balance while also contributing to the circular bioeconomy that promotes sustainable development.

关键词： Biorefinery Circular bioeconomy Agro-industrial by-products High-added-value products Sustainable development

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