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Expanding the donor pool: Hepatitis C, hepatitis B and human immunodeficiency virus-positive donors in liver transplantation

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World Journal of Gastroenterology 2019年第47期25卷 6799-6812页

作者： james f Crismale Jawad Ahmad Division of Liver Diseases Icahn School of Medicine at Mount Sinai

Liver transplantation(LT)remains the best option for patients with end-stage liver disease but the demand for organs from deceased donors continues to outweigh the available *** advent of highly effective anti-viral treatments has reduced the number of patients undergoing LT for hepatitis C(HCV)and hepatitis B(HBV)related liver disease and yet the number of patients waiting for LT continues to increase,driven by an increase in the patients listed with a diagnosis of cirrhosis due to non-alcoholic steatohepatitis and alcoholrelated liver *** addition,human immunodeficiency virus(HIV)infection,which was previously a contra-indication for LT,is no longer a fatal disease due to the effectiveness of HIV therapy and patients with HIV and liver disease are now developing indications for *** rising demand for LT is projected to increase further in the future,thus driving the need to investigate potential means of expanding the pool of potential *** mechanism for doing so is utilizing organs from donors that previously would have been discarded or used only in exceptional circumstances such as HCV-positive,HBV-positive,and HIVpositive *** advent of highly effective anti-viral therapy has meant that these organs can now be used with excellent outcomes in HCV,HBV or HIV infected recipients and in some cases uninfected recipients.

关键词： Hepatitis C Hepatitis B Human immunodeficiency virus Liver transplantation

Modeling the Newtonian dynamics for rotation curve analysis of thin-disk galaxies

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Research in Astronomy and Astrophysics 2011年第12期11卷 1429-1448页

作者： james Q.feng C.f.Gallo Superconix Inc 2440 Lisbon AvenueLake ElmoMN 55042USA

We present an efficient, robust computational method for modeling the Newtonian dynamics for rotation curve analysis of thin-disk galaxies. With appropriate mathematical treatments, the apparent numerical difficulties associated with singularities in computing elliptic integrals are completely removed. Using a boundary element discretization procedure, the governing equations are transformed into a linear algebra matrix equation that can be solved by straightforward Gauss elimination in one step without further iterations. The numerical code implemented according to our algorithm can accurately determine the surface mass density distribution in a disk galaxy from a measured rotation curve （or vice versa）. for a disk galaxy with a typical flat rotation curve, our modeling results show that the surface mass density monotonically decreases from the galactic center toward the periphery, according to Newtonian dynamics. In a large portion of the galaxy, the surface mass density follows an approximately exponential law of decay with respect to the galactic radial coordinate. Yet the radial scale length for the surface mass density seems to be generally larger than that of the measured brightness distribution, suggesting an increasing mass-tolight ratio with the radial distance in a disk galaxy. In a nondimensionalized form, our mathematical system contains a dimensionless parameter which we call the ＂galactic rotation number＂ that represents the gross ratio of centrifugal force and gravitational force. The value of this galactic rotation number is determined as part of the numerial solution. Through a systematic computational analysis, we have illustrated that the galactic rotation number remains within 4-10% of 1.70 for a wide variety of rotation curves. This implies that the total mass in a disk galaxy is proportional to V02 Rg, with V0 denoting the characteristic rotation velocity （such as the ＂flat＂ value in a typical ro- tation curve） and Rg the radius of the galacti

关键词： galaxy: disk -- galaxies: general -- galaxies: kinematics and dynamics -- galaxies: structure -- methods: numerical and analytical

The song remains the same： Juvenile Richardson＇s ground squirrels do not respond differentially to mother＇s or colony member＇s alarm calls

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Current Zoology 2012年第5期58卷 773-780页

作者： james f. HARE Kurtis J. WARKENTIN Department of Biological Sciences University of Manitoba Winnipeg MB Canada R3T 2N2 Department of Zoology Brandon University Brandon MB R7A 6A9

Alarm calls are emitted by Richardson＇s ground squirrels Urocitellus richardsonii in response to avian and terrestrial predators. Conspecifics detecting these calls respond with increased vigilance, promoting predator detection and evasion, but in doing so, lose time from foraging. That loss can be minimized if alarm call recipients discriminate among signalers, and weight their response accordingly. for juvenile ground squirrels, we predicted that the trade-off between foraging and vigilance could be optimized via selective response to alarm calls emitted by their own dam, and/or neighboring colony members over calls broad- cast by less familiar conspecifics. Alarm calls of adult female Richardson＇s ground squirrels were elicited in the field using a predator model and recorded on digital audio tape. free-living focal juveniles were subjected to playbacks of a call of their mother, and on a separate occasion a call from either another adult female from their own colony, or an adult female from another colony. Neither immediate postural responses and escape behavior, nor the duration of vigilance manifested by juveniles differed with exposure to alarm calls of the three adult female signaler types. Thus, juveniles did not respond preferentially to alarm calls emitted by their mothers or colony members, likely reflecting the high cost of ignoring alarm signals where receivers have had limited opportunity to establish past signaler reliability [Current Zoology 58 （5）： 773-780, 2012].

关键词： Alarm Signal Communication Maternal Call Recognition Signal Reliability Ground Squirrel Social Discrimination

Evaluation of the Quality of Micturition in Patients Who Underwent Anastomotic Urethroplasty at the Yaounde Central Hospital, Cameroon

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Open Journal of Urology 2024年第2期14卷 115-127页

作者： Achille Aurele Mbassi Landry Oriole Mbouche Junior Mekeme Mekeme Jean Crepin Eloundou Nkolo Bright Che Awondo Jean Cedrik fouda frantz Guy Epoupa Ngalle Cyril Kamadjou Pamela Anaba Laure Pierre Joseph fouda fru forbuzshi iii Angwafo Higher Institute of Medical Technology Yaounde Cameroon Higher Institute of Health Sciences Bangangte Cameroon Urology and Andrology Department Yaounde Central Hospital Yaounde Cameroon Department of Surgery and Subspecialties Faculty of Medicine and Biomedical Sciences University of Yaounde 1 Yaounde Cameroon Yaounde Gynecology Obstetrics and Pediatric Hospital Yaounde Cameroon

Introduction: Radiological investigation which is the gold standard to perform following anastomotic urethroplasty in order to evaluate the quality of micturition is costly. In our context, due to financial limitations, reconstructive urologists prefer to use the uroflowmetry in order to assess the micturition post-surgery. Therefore, the objective of the study was to assess the quality of micturition using the uroflowmetry after anastomotic urethroplasty. Methodology: We conducted an 11-year retrospective review (1st January 2006-31st December 2017) and a cross-sectional descriptive observational study for a period of 8 months (November 2017-June 2018) at the Urology and Andrology Department of the Yaounde Central Hospital (YCH) of patients who were diagnosed with urethral stenosis and underwent an anastomotic urethroplasty at the YCH. We excluded patients who had incomplete files, patients lost to follow-up and did not do pre-operative uroflowmetry. Quality of micturition was evaluated using a uroflowmetry. Data was analyzed using EPI info 7.0. Parametric variables were reported as means and standard deviations and percentages and counts were used to report categorical variables. Results: We had a sample of 60 patients. The mean age was 42 ± 5 years with extremes ranging from 20 to 76 years. Twenty-seven (27) patients, or 45%, had no post-operative complications, and those who did had a urinary tract infection (26.70%). In our series, we had 82% excellent results (patient satisfied with his urination with bell-shaped urinary stream and urinary flow greater than or equal to 15 ml/sec);15% good results (patient with moderate dysuria with average urinary stream and urinary flow between 10 and 14.9 ml/sec) and 3% poor results (severe dysuria with urinary flow less than 10 ml/sec, urinary retention or urinary incontinence). Based on these results we can say that the success rate in our series was 97%. 96.70% of patients were satisfied against 3.3%

关键词： Urethra Stricture Anastomotic Urethroplasty

Burrowing Richardson's ground squirrels affect plant seedling assemblages via environmental but not seed bank changes

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Current Zoology 2020年第3期66卷 219-226页

作者： Levi J.Newediuk james f.Hare Department of Biological Sciences University of ManitobaWinnipegManitobaCanada R3T 2N2

In grassland ecosystems,burrowing mammals create disturbances,providing habitat for animal species and increasing plant community *** investigated whether seedling assemblages on Richardson's ground squirrel Urocitellus richardsonii mounds result from seed rearrangement or environmental changes that favor germination of certain species over *** test whether ground squirrels rearrange the seed bank by burrowing,we compared seed compositions among mounds,burrows,and undisturbed *** test whether ground squirrels change environmental conditions,we compared soil nitrate and bare ground cover on and off *** also compared seedlings that germinated on mounds with seedlings that germinated on artificial disturbances from which we removed aboveground *** nitrate and bare ground cover were significantly higher on mounds than artificial *** seed richness and abundance did not differ among mounds,burrows,and undisturbed soil,seedling richness was reduced on mounds relative to artificial *** disturbance favors seedlings that can capitalize on bare ground availability but are less able to immobilize nitrate,as opposed to perennial species that immobilize more nitrate but take longer to *** results suggest that Richardson's ground squirrels act as ecosystem engineers,although future research following succession on ground squirrel mounds is necessary to understand how they influence plant communities past the seedling stage.

关键词： burrowing disturbance ecosystem engineering Richardsons ground squirrel seed bank seedling species composition

fully integrated and broadband Si-rich silicon nitride wavelength converter based on Bragg scattering intermodal four-wave mixing

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Photonics Research 2024年第3期12卷 I0001-I0010页

作者： VALERIO VITALI THALÍA DOMÍNGUEZ BUCIO HAO LIU JOSÉMANUEL LUQUE GONZÁLEZ fRANCISCO JURADO-ROMERO ALEJANDRO ORTEGA-MOÑUX GLENN CHURCHILL james C.GATES james HILLIER NIKOLAOS KALfAGIANNIS DANIELE MELATI JENS H.SCHMID ILARIA CRISTIANI PAVEL CHEBEN J.GONZALO WANGÜEMERT-PÉREZ ÑIGO MOLINA-fERNÁNDEZ fREDERIC GARDES COSIMO LACAVA PERIKLIS PETROPOULOS Optoelectronics Research Centre University of SouthamptonSouthampton SO171BJUK Electrical Computer and Biomedical Engineering DepartmentUniversity of PaviaPavia 27100Italy Telecommunication Research Institute(TELMA) Universidad de MálagaCEI Andalucı´a TECHE.T.S.I.Telecomunicación29010 MálagaSpain School of Science and Technology Nottingham Trent UniversityNottingham NG118NSUK Department of Electrical Engineering Eindhoven University of TechnologyEindhoven 5600 MBThe Netherlands Department of Materials Science and Engineering University of IoanninaIoannina 45110Greece Centre de Nanosciences et de Nanotechnologies UniversitéParis-SaclayCNRS91120 PalaiseauFrance Advanced Electronics and Photonics Research Center National Research Council CanadaOttawaOntario K1A 0R6Canada

Intermodal four-wave mixing(fWM)processes have recently attracted significant interest for all-optical signal processing applications thanks to the possibility to control the propagation properties of waves exciting distinct spatial modes of the same *** allows,in principle,to place signals in different spectral regions and satisfy the phase matching condition over considerably larger bandwidths compared to intramodal ***,the demonstrations reported so far have shown a limited bandwidth and suffered from the lack of on-chip components designed for broadband manipulation of different *** demonstrate here a silicon-rich silicon nitride wavelength converter based on Bragg scattering intermodal fWM,which integrates mode conversion,multiplexing and de-multiplexing functionalities *** system enables wavelength conversion between pump waves and a signal located in different telecommunication bands(separated by 60 nm)with a 3 dB bandwidth exceeding 70 nm,which represents,to our knowledge,the widest bandwidth ever achieved in an intermodal fWM-based system.

关键词： scattering pump modal

Design of Poiseuille flow Controllers Using the Method of Inequalities

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International Journal of Automation and computing 2009年第1期6卷 14-21页

作者： John McKernan james f. Whidborne George Papadakis Department of Mechanical Engineering King s College London Strand Department of Aerospace Sciences Cranfield University

This paper investigates the use of the method of inequalities （MoI） to design output-feedback compensators for the problem of the control of instabilities in a laminar plane Poiseuille flow. In common with many flows, the dynamics of streamwise vortices in plane Poiseuille flow are very non-normal. Consequently, small perturbations grow rapidly with a large transient that may trigger nonlinearities and lead to turbulence even though such perturbations would, in a linear flow model, eventually decay. Such a system can be described as a conditionally linear system. The sensitivity is measured using the maximum transient energy growth, which is widely used in the fluid dynamics community. The paper considers two approaches. In the first approach, the MoI is used to design low-order proportional and proportional-integral （PI） controllers. In the second one, the MoI is combined with Mcfarlane and Glover＇s H∞ loop-shaping design procedure in a mixed-optimization approach.

关键词： Transient energy growth transient behaviour flow control Poiseuille flow method of inequalities (MoI) mixed opti-mization H∞-optimization.

Perceptual tolerance neighborhood-based similarity in content-based image retrieval and classification

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International Journal of Intelligent Computing and Cybernetics 2012年第2期5卷 164-185页

作者： Amir H.Meghdadi james f.Peters Electrical and Computer Engineering University of ManitobaWinnipegCanada School of Mathematics University of HyderabadHyderabadIndia

Purpose–The purpose of this paper is to demonstrate the effectiveness and advantages of using perceptual tolerance neighbourhoods in tolerance space-based image similarity measures and its application in content-based image classification and ***/methodology/approach–The proposed method in this paper is based on a set-theoretic approach,where an image is viewed as a set of local visual *** method also includes a tolerance relation that detects the similarity between pairs of elements,if the difference between corresponding feature vectors is less than a threshold 2(0,1).findings–It is shown that tolerance space-based methods can be successfully used in a complete content-based image retrieval(CBIR)***,it is shown that perceptual tolerance neighbourhoods can replace tolerance classes in CBIR,resulting in more accuracy and less ***/value–The main contribution of this paper is the introduction of perceptual tolerance neighbourhoods instead of tolerance classes in a new form of the Henry-Peters tolerance-based nearness measure(tNM)and a new neighbourhood-based tolerance-covering nearness measure(tcNM).Moreover,this paper presents a side–by–side comparison of the tolerance space based methods with other published methods on a test dataset of images.

关键词： Image similarity Nearness measure Distance measurement Content-based image retrieval(CBIR) Perceptual tolerance neighbourhoods Tolerance spaces Tolerances Measurement

In the forest vine Smilax rotundifolia,fungal epiphytes show site-wide spatial correlation,while endophytes show evidence of niche partitioning

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fungal Diversity 2015年第6期75卷 279-297页

作者： Christopher B.Zambell james f.White Graduate Program in Ecology&Evolution Rutgers UniversityNew BrunswickNJ 08901USA Department of Plant Biology&Pathology 59 Dudley RoadNew BrunswickNJ 08901USA

Endophytic and epiphytic fungal assemblages from stems of ***,a shrubby vine,were studied in order to(1)quantify differences and the degree of overlap between fungal communities of both micro-habitats,and(2)examine whether fungal assemblages are spatially correlated at the local scale(tens to hundreds of meters),in order to understand if dispersal limitation may play a role in structuring these *** was conducted over 160 m of growth along a forest *** communities showed low overlap(Bray-Curtis Similarity=0.22),with most species that were common in one habitat appearing rarely if at all in the other,and only Aureobasidium pullulans showing high frequency in *** assemblages proved to be spatially correlated along the 160 m length of the transect,and even more so when adjacent pairs of stems were considered as the unit of comparison rather than individual *** assemblages showed no significant spatial correlation along the ***,three species of endophytes showed a pattern in which abundance of colonies peaked at different heights on the *** boninense showed peak abundance at 3 cm from the stem *** sp.1 peaked at 33 cm from the stem *** isolates of *** peaked at 63 cm from the stem *** was also found that positive correlative relationships were detected between endophyte-endophyte,and epiphyte-epiphyte ***-group interactions seemed to center around crossover species that were not entirely constrained within the surface or interior.

关键词： Colletotrichum Phomopsis Phyllosticta Local dispersal Tissue preference