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Effective Interaction Force between an Electric Charge and a Magnetic Dipole and Locality (or Nonlocality) in Quantum Effects of the Aharonov–Bohm Type

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Chinese Physics Letters 2021年第3期38卷 39-43页

作者： Gianfranco Spavieri George T.Gillies Miguel rodriguez Maribel perez Centro de Física Fundamental Facultad de CienciasUniversidad de Los AndesMérida 5101Venezuela Department of Mechanical and Aerospace Engineering University of VirginiaCharlottesvilleVA 22904USA Departamento de Física Facultad de Ciencia y TecnologíaUniversidad de CaraboboNaguanagua 2001Venezuela Carrera de Ingeniería Ambiental Facultad de IngenieríaUniversidad Nacional de ChimborazoRiobamba 100150Ecuador

Classical electrodynamics foresees that the effective interaction force between a moving charge and a magnetic dipole is modified by the time-varying total momentum of the interaction fields. We derive the equations of motion of the particles from the total stress-energy tensor, assuming the validity of Maxwell’s equations and the total momentum conservation law. Applications to the effects of Aharonov–Bohm type show that the observed phase shift may be due to the relative lag between interfering particles caused by the effective local force.

关键词： force. momentum interaction

Calibration of Modified Spalart-Ailmaras Model Parameters for Linear Compressor Cascade Corner Flow

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Journal of Thermal Science 2022年第1期31卷 163-172页

作者： MATSUI Kotaro perez Ethan KELLY Tryan TANI Naoki JEMCOV Aleksandar IHI Corporation Akishima 196-8686Japan Notre Dame Turbomachinery Laboratory South Bend 46601USA Department of Aerospace and Mechanical Engineering University of Notre DameNotre Dame 46556USA

In this study,Bayesian parameter calibration is applied to Saplart-Allmaras(SA)turbulence model,and the prediction improvement by the calibrated model is *** quantity of interest(QOI)is the pitch-wise distribution of Mach number in the comer separation flow *** 10 model parameters included in the SA model with rotation-Curvature correction are considered as random variables obeying uniform prior probability *** order of generalized Polynomial Chaos(gPC)used for sensitivity analysis and surrogate model in calibration is incrementally increased during the calibration *** convergence is obtained at the 3rd order expansion level in this *** this final level,sensitivity analysis indicates 3 model parameters,cbl,k and cr3 are the most influential random variables,and 3-parameter Bayesian calibration is *** likelihood function in the Bayesian theorem is specified in the form of Gaussian distribution,including experimental *** combination of prior and likelihood brings the posterior distribution of model parameters,and Maximum A Posterior(MAP)value is selected as a calibrated parameter *** flow simulation with calibrated parameters shows a significant increase in the accuracy of the Mach number profile in the comer separation *** increase in accuracy is attributed to enlarged turbulent viscosity due to the parameter modification of the turbulent viscosity source *** calibrated parameter is also tested in the off-design flow field,not included in the calibration *** calibrated CFD again shows improved accuracy for comer separation prediction,and the effectiveness of the parameter set outside of the calibration field is demonstrated.

关键词： compressor corner flow turbulence model calibration

Generalized Multiscale rBF Networks and the DCT for Breast Cancer Detection

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International Journal of Automation and computing 2020年第1期17卷 55-70页

作者： Carlos Beltran-perez Hua-Liang Wei Adrian rubio-Solis Department of Automatic Control and Systems Engineering University of SheffieldSheffield S13JDUK Tecnologico de Monterrey Campus TolucaEduardo Monroy Cardenas 2000San Antonio BuenavistaToluca 50110Mexico

The use of the multiscale generalized radial basis function(MSrBF)neural networks for image feature extraction and medical image analysis and classification is proposed for the first time in this *** MSrBF networks hold a simple and flexible architecture that has been successfully used in forecasting and model structure detection of input-output nonlinear *** this work instead,MSrBF networks are part of an integrated computer-aided diagnosis(CAD)framework for breast cancer detection,which holds three stages:an input-output model is obtained from the image,followed by a high-level image feature extraction from the model and a classification module aimed at predicting breast *** the first stage,the image data is rendered into a multiple-input-single-output(MISO)*** order to improve the characterisation,the nonlinear autoregressive with exogenous inputs(NArX)model is introduced to rearrange the available input-output data in a nonlinear *** forward regression orthogonal least squares(FrOLS)algorithm is then used to take advantage of the previous arrangement by solving the system as a model structure detection problem and finding the output layer weights of the NArX-MSrBF *** the second stage,once the network model is available,the feature extraction takes place by stimulating the input to produce output signals to be compressed by the discrete cosine transform(DCT).In the third stage,we leverage the extracted features by using a clustering algorithm for classification to integrate a CAD system for breast cancer *** test the method performance,three different and well-known public image repositories were used:the mini-MIAS and the MMSD for mammography,and the BreaKHis for histopathology images.A comparison exercise was also made between different database partitions to understand the mammogram breast density effect in the performance since there are few remarks in the literature on this *** results show that

关键词： Nonlinear system identification image processing discrete cosine transform radial basis functions computer-aided diagnosis neural networks

Memory for location and visual cues in white-eared hummingbirds Hylocharis leucotis

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Current Zoology 2011年第4期57卷 468-476页

作者： Guillermo perez Carlos LArA Jose VICCON-PALE Martha SIGNOrET-POILLON Doctorado en Ciencias Biologicas Universidad Autonoma Metropolitana. Unidad Xochimilco. Calzada del Hueso 1100 Col. Villa Quietud 04960 Moxico D.F. Moxico Laboratorio de Ecologfa de la Conducta Centro Tlaxcala de Biologfa de la Conducta UAT-UNAM Km 1.5 carretera Tlaxcala- Puebla s/n Colonia Xicohtoncatl Apdo. Postal 262 Tlaxcala Tlaxcala 90070 Moxico. Departamento el Hombre y su Ambiente. Universidad Autdnoma Metropolitana. Unidad Xochimilco. Calzada del Hueso 1100 Col. Villa Quietud 04960 MExico D.F. Mexico

In nature hummingbirds face floral resources whose availability, quality and quantity can vary spatially and temporally. Thus, they must constantly make foraging decisions about which patches, plants and flowers to visit, partly as a function of the nectar reward. The uncertainty of these decisions would possibly be reduced if an individual could remember locations or use visual cues to avoid revisiting recently depleted flowers. In the present study, we carried out field experiments with white-eared hummingbirds Hylocharis leucotis, to evaluate their use of locations or visual cues when foraging on natural flowers Penstemon roseus. We evaluated the use of spatial memory by observing birds while they were foraging between two plants and within a single plant. Our results showed that hummingbirds prefer to use location when foraging in two plants, but they also use visual cues to efficiently locate unvisited rewarded flowers when they feed on a single plant. However, in absence of visual cues, in both experiments birds mainly used the location of previously visited flowers to make subsequent visits. Our data suggest that hummingbirds are capable of learning and employing this flexibility depending on the faced environmental conditions and the information acquired in previous visits [Current Zoology 57 （4）： 468-476, 2011].

关键词： Visual cues Location White-eared hummingbird Foraging

Immediate post-operative complications(I):Post-operative bleeding;vascular origin:Thrombosis pancreatitis

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World Journal of Transplantation 2020年第12期10卷 415-421页

作者： Jose Antonio perez Daga rosa perez rodriguez Julio Santoyo Department of Surgery Hospital Regional de MálagaMalaga 29010Spain

Simultaneous pancreas-kidney transplantation is the treatment of choice forinsulin-dependent diabetes that associates end-stage diabetic nephropathy, sinceit achieves not only a clear improvement in the quality of life, but also provides along-term survival advantage over isolated kidney transplant. However, pancreastransplantation still has the highest rate of surgical complications among organtransplants. More than 70% of early graft losses are attributed to technical failures,that is, to a non-immunological cause. The so-called technical failures includegraft thrombosis, bleeding, infection, pancreatitis, anastomotic leak and pancreaticfistula. Pancreatic graft thrombosis leads these technical complications as the mostfrequent cause of early graft loss. Currently most recipients receive postoperativeanticoagulation with the aim of reducing the rate of thrombosis. Hemoperitoneumin the early postoperative period is a frequent cause of relaparotomy, but it is notusually associated with graft loss. The incidence of hemoperitoneum is clearlyrelated to the use of anticoagulation in the postoperative period. Post-transplantpancreatitis is another cause of early postoperative complications, less frequentthan the previous. In this review, we analyze the most common surgicalcomplications that determine pancreatic graft losses.

关键词： Pancreas transplantation Vascular graft thrombosis Postoperative hemorrhage Graft pancreatitis reperfusion injury Tissue donors risk factors

Serratia fonticola and its role as a single pathogen causing emphysematous pyelonephritis in a non-diabetic patient:A case report

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World Journal of Clinical Cases 2022年第29期10卷 10600-10605页

作者： Victor Villasuso-Alcocer Juan P Flores-Tapia Fernando perez-Garfias Andrea rochel-perez Nina Mendez-Dominguez Scholar at Direccion General de Calidad y Educacion en Salud Secretaría de SaludMexico 11570Mexico Urology Department Hospital Regional de Alta Especialidad de la Peninsula de YucatanMerida 97300YucatanMexico research and Learning Hospital Regional de Alta Especialidad de la Peninsula de YucatanMerida 97130YucatanMexico

BACKGrOUND Diagnosis of emphysematous pyelonephritis has been described around the world for some decades,frequently associated with Escherichia coli and other anaerobic,gas-forming bacteria and mostly in patients living with *** present a case report of emphysematous pyelonephritis in a non-diabetic patient caused by Serratia fonticola as well as a brief literature review to draw attention to this rare pathogen as a cause of *** SUMMArY A 38-year-old female presented with fever,severe pain in the right flank and changes in urinary *** was admitted,and emphysematous pyelonephritis was confirmed by an abdominal computerized tomography and urine cultures;the latter showed Serratia fonticola as a single *** 3 d of being treated with piperacillin/tazobactam and percutaneous drainage she became afebrile,and the gas presence *** Emphysematous pyelonephritis infections in non-diabetic patients are rare but can be severe and *** case suggests that Serratia fonticola infection can occur in patients undergoing invasive or instrumented procedures.

关键词： Serratia fonticola Emphysematous pyelonephritis Urinary tract infections Nephrolithiasis Case report

Surgical management of necrotizing pancreatitis:An overview

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World Journal of Gastroenterology 2014年第43期20卷 16106-16112页

作者： George Kokosis Alexander perez Theodore N Pappas Department of Surgery Duke University Medical CenterDurhamNC 27705United States

Necrotizing pancreatitis is an uncommon yet serious complication of acute pancreatitis with mortality rates reported up to 15%that reach 30%in case of *** open surgical debridement was the only tool in our disposal to manage this serious clinical *** approach is however associated with poor *** has now shifted away from open surgical debridement to a more conservative management and minimally invasive *** approach to patients with necrotizing pancreatitis and/or infectious pancreatitis is summarized in the 3Ds:Delay,Drain and *** can be managed in the intensive care unit and any intervention should be *** drainage can be utilized first and early in the course of the disease,followed by endoscopic drainage or video assisted retroperitoneoscopic drainage if necrosectomy is deemed *** surgery is now less frequently performed and should be reserved for cases refractory to any other *** management of necrotizing pancreatitis therefore requires a multidisciplinary dynamic model of approach rather than being a surgical disease.

关键词： Necrotizing pancreatitis Severe acute pancreatitis Debridement Necrosectomy Infected necrosis Endoscopic necrosectomy Video-assisted retroperitoneal debridement Percutaneous catheter drainage

Synthetic biology identifies the minimal gene set required for paclitaxel biosynthesis in a plant chassis

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Molecular Plant 2023年第12期16卷 1951-1961页

作者： Youjun Zhang Lorenz Wiese Hao Fang Saleh Alseekh Leonardo perez de Souza Federico Scossa John Molloy Mathias Christmann Alisdair r.Fernie Max-Planck-Institut fur Molekulare Pflanzenphysiologie Am Muhlenberg 114476 Potsdam-GolmGermany Center of Plant Systems Biology and Biotechnology 4000 PlovdivBulgaria Institute of Chemistry and Biochemistry Freie Universitat BerlinTakustraBe 314195 BerlinGermany Department of Biomolecular Systems Max Planck Institute of Colloids and Interfaces14476 PotsdamGermany research Center for Genomics and Bioinformatics(CrEA-GB) Via Ardeatina 54600178 RomeItaly

The diterpenoid paclitaxel(Taxol)is a chemotherapy medication widely used as a first-line treatment against several types of solid *** supply of paclitaxel from natural sources is ***,missing knowledge about the genes involved in several specific metabolic steps of paclitaxel biosynthesis has rendered it difficult to engineer the full *** this study,we used a combination of transcriptomics,cell biology,metabolomics,and pathway reconstitution to identify the complete gene set required for the heterologous production of *** identified the missing steps from the current model of paclitaxel biosynthesis and confirmed the activity of most of the missing enzymes via heterologous expression in Nicotiana ***,we identified a new C4β-C20 epoxidase that could overcome the first bottleneck of metabolic *** used both previously characterized and newly identified oxomutases/epoxidases,taxane 1β-hydroxylase,taxane 9aα-hydroxylase,taxane 9α-dioxygenase,and phenylalanine-CoA ligase,to successfully biosynthesize the key intermediate baccatin Ill and to convert baccatin Ill into paclitaxel in *** combination,these approaches establisha metabolic route to taxoidbiosynthesis and provide insights into the unique chemistry that plants use to generate complex bioactive metabolites.

关键词： paclitaxel biosynthesis synthetic biology baccatin Ill biosynthesis Taxus

Comparison of four methods to evaluate sperm DNA integrity between mouse caput and cauda epididymidis

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Asian Journal of Andrology 2012年第2期14卷 335-337页

作者： Serafin perez-Cerezales： Alberto Miranda Alfonso Gutierrez-Adan Department of Animal reproduction National Institute for Agricultural and Food Research and Technology Madrid 28040 Spain

It is well known that transit through the epididymis involves an increase in the compaction of sperm chromatin, which acquires fully condensed status at the caput epididymidis. The purpose of this study was to compare the terminal deoxyribonucleotidyl transferase-mediated dUTP nick end-labelling （TUNEL） assay, the comet assay, the sperm chromatin structure assay （SCSA） and the sperm chromatin dispersion （SCD） test by analysing spermatozoa from the caput and cauda epididymidis in order to demonstrate the ability of each technique to discriminate between different degrees of sperm maturity related to chromatin compaction and DNA fragmentation. Our results suggest that some populations of DNA-fragmented spermatozoa associated with immature sperm can only be identified using the comet assay and the SCSA but not with the SCD test or the TUNEL assay.

关键词： DNA damage mouse epididymis sperm chromatin sperm maturation the comet assay the sperm chromatin dispersion test the sperm chromatin structure assay TUNEL