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The Nikola Tesla Constant and Its Relation to the Circumf.rence Inscribed in a Square

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Journal of.Applied Mathematics and Physics 2024年第1期12卷 277-283页

作者： Javier Mendoza Navarrete José Ismael Ojeda Campaña Huetzin Perez Gabriel Luna-Sandoval victor Verdugo Ricardo Jiménez Garcia Departamento de Matemáticas CBTis 256 DGETI Cabo San Lucas México División de Ingeniería en Sistemas Computacionales Tecnológico Nacional de México/ITES de Los Cabos Cabo San Lucas México DCI Departamento de f.sica Médica Universidad de Guanajuato León México Departamento de Ingeniería Industrial en Manuf.ctura Universidad Estatal de Sonora Navojoa México Departamento de Eléctrica-Electrónica Tecnológico Nacional de México Campus Mexicali Mexicali México

This research work relates the surf.ce of.a square and the area circumscribed by a circle, resulting in a value called Nikola Tesla constant. This constant starts with the calculation of.the areas of.the square and the inscribed circle, giving a ratio of.9/40 and f.om which a residual area of.the area proportions of.the geometric f.gures described is obtained. Plotting smooth curves, particularly those in round shapes, can be represented ef.iciently with the use of.Nikola Tesla constant, reducing complex mathematical calculus.

关键词： Tesla Numbers Prime Number Circle Binary Area

f.nctional Roux-en-Y Gastric Bypass (f.RYGB), with Preservation of.Duodenal Access: Report of.Two Revisional Cases of.Sleeve Gastrectomy

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Surgical Science 2024年第3期15卷 135-158页

作者： victor Ramos Mussa Dib Carlos Augusto Scussel Madalosso Paulo Reis Esselin de Melo Rui Ribeiro Paula Volpe Carlos Eduardo Domene victor Dib Institute Manaus Brazil Gastrobese Clinic Passo Fundo Brazil Paulo Reis Institute of.Bariatric Surgery Goi&#226nia Brazil Alf.edo Nasser University Center (UNIf.N) Goi&#226nia Brazil Lusíadas Amadora Hospital Lisboa Portugal Integrated Center f.r Advanced Medicine (CIMAMED) S&#227o Paulo Brazil

Objective: This case report aimed to demonstrate a possible neuromuscular ef.ect of.Latarjet nerves transection or truncal vagotomy, in association with sleeve gastrectomy plus antrojejunostomy, in order to reproduce a Roux-en-Y gastric bypass (RYGB) mechanistic principles, in patients with previous Sleeve Gastrectomy (SG) who had had weight regain, with or without concomitant gastroesophageal ref.ux disease (GERD). Background: Sleeve gastrectomy (SG) is one of.the most f.equently perf.rmed bariatric operations worldwide. Nevertheless, weight regain and gastroesophageal ref.ux disease (GERD) have been consistently demonstrated, in association with this technique, which may require a revisional procedure. RYGB is an option in such a situation but, implies in gastrointestinal exclusions, which represents a shortcoming of.this revision. Surpassing this inconvenient would be of.great value f.r the patients. Methods: We describe herein two cases of.SG revision f.r weight regain and GERD, with a f.llow-up of.one year. Gastroesophageal ref.ux disease was evaluated by validated questionnaire, upper endoscopy, seriography, high resolution manometry (HRM) and impedance pHmetry (I-pHmetry), in the pre and postoperative periods. A re-Sleeve Gastrectomy with antrojejunal anastomosis was done in both cases, af.er inf.rmed consents. The Latarjet nerves were transected in one case, due to a bleeding in the lef. gastric vessels and a truncal vagotomy was required in the other, to appropriately treat an associated hiatal hernia. Results: In the postoperative evaluation it was observed a pyloric spasm in both cases, during seriography and endoscopy, kept until the one-year f.llow-up. There was unidirectional contrast f.ow to the gastrointestinal anastomosis, f.lling the jejunal limb, in radiologic contrast study. No contrast passed through the pylorus. Nonetheless, the duodenum was kept endoscopically accessible. In the one-year evaluation, weight loss was adequate and GERD resolution

关键词： Roux-en-Y Gastric Bypass Sleeve Gastrectomy Jejuno Gastric Bypass Vagus Nerve Vagotomy Bariatric Surgery

Quantitative Assessment of.Liver f.brosis by Elastography in Patients with Chronic Liver Disease: A Cross-Sectional Study in Lomé (Togo)

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Open Journal of.Radiology 2024年第2期14卷 42-54页

作者： Massaga Dagbe Bidamin N’timon Sonia Ekembe Raf.ou El-Hadji Yakoubou Pihou Gbande Lantam Sonhaye Lama Kegdigoma Agoda-Koussema Komlanvi victor Adjenou Department of.Radiology and Medical Imaging Kara University Hospital Kara Kara Togo Department of.Radiology and Medical Imaging Lom University Hospital Lome Togo Department of.Hpato-gastroenterology Kara University Hospital Kara Togo Department of.Radiology and Medical Imaging Sokod Regional Hospital Sokode Togo Department of.Internal Medicine Kara University Hospital Kara Togo

Aim: To describe the two-dimensional elastographic prof.le according to the Shearwave (2D-SWE) technique in patients with chronic liver disease in Lom. Materials and method: Cross-sectional, descriptive study conducted over seven month at the Autel dElie Clinic in Lom, f.om January to August 2022, on adult patients with chronic liver disease who underwent abdominal ultrasound coupled with two-dimensional elastography. Results: The sample size was 54 patients. The mean age of.the patients was 33 12 years, with extremes of.18 and 66 years. Patients aged 30 years or less accounted f.r 48.1% (n = 26). All patients (n = 54) had at least one transaminase assay with a mean of.69.3 78.3 IU/l (AST) and 59.3 82.8 IU/l (ALT). There was no statistically signif.cant association between the biological parameters and the presence of.f.brosis. Viral liver disease was the main cause, accounting f.r 81.5% (n = 44) of.cases, with no signif.cant association with the degree of.f.brosis. Ultrasound revealed a dysmorphic liver (57.4%;n = 31) and portal hypertension (18.5%, n = 10). f.brosis stages f., f. and f. accounted f.r (48.1%, n = 26), (24.1%, n = 13) and (13%, n = 7) of.cases respectively. Liver dysmorphia was signif.cantly associated with the presence of.f.brosis (p = 0.012) and portal hypertension was signif.cantly associated with the degree of.f.brosis (p = 0.0063). Conclusion: Assessment of.liver f.brosis in patients with chronic liver disease using 2D-SWE elastography is essential f.r patient f.llow-up.

关键词： Hepatic f.brosis 2D-SWE Elastography Chronic Liver Disease Lomé

Evaluation of.dif.erent machine learning methods f.r land cover mapping of.a Mediterranean area using multi-seasonal Landsat images and Digital Terrain Models

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International Journal of.Digital Earth 2014年第6期7卷 492-509页

作者： victor f.Rodriguez-Galiano Mario Chica-Rivas Departamento de Geodinamica Universidad de GranadaGranadaSpain Departamento de Analisis Matematico Universidad de GranadaGranadaSpain

Land cover monitoring using digital Earth data requires robust classif.cation methods that allow the accurate mapping of.complex land cover *** paper discusses the crucial issues related to the application of.dif.erent up-to-date machine learning classif.ers:classif.cation trees(CT),artif.cial neural networks(ANN),support vector machines(SVM)and random f.rest(Rf..The analysis of.the statistical signif.cance of.the dif.erences between the perf.rmance of.these algorithms,as well as sensitivity to data set size reduction and noise were also ***-5 Thematic Mapper data captured in European spring and summer were used with auxiliary variables derived f.om a digital terrain model to classif. 14 dif.erent land cover categories in south ***,statistically similar accuracies of.over 91%were obtained f.r ANN,SVM and ***,the f.ndings of.this study show dif.erences in the accuracy of.the classif.ers,being Rf.the most accurate classif.er with a very simple ***,f.llowed by Rf.was the most robust classif.er to noise and data *** dif.erences in their perf.rmances were only reached f.r thresholds of.noise and data reduction greater than 20%(noise,SVM)and 25%(noise,Rf.,and 80%(reduction,SVM)and 50%(reduction,Rf.,respectively.

关键词： land cover remote sensing classif.cation trees random f.rest neural networks support vector machines

Dissolved organic carbon in permaf.ost regions: A review

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Science China Earth Sciences 2019年第2期62卷 349-364页

作者： Qiang MA Huijun JIN Congrong YU victor f.BENSE State Key Laboratory of.f.ozen Soils Engineering Northwest Institute of Eco-Environment and Resources Chinese Academy of Sciences College of.Resources and Environment University of.Chinese Academy of.Sciences School of.Civil Engineering Harbin Institute of Technology State Key Laboratory of.Hydrology-Water Resources and Hydraulic Engineering Hohai University Hydrology and Quantitative Water Management Group Department of Environmental Sciences Wageningen University

A large quantity of.organic carbon(C) is stored in northern and elevational permaf.ost regions. A portion of.this large terrestrial organic C pool will be transf.rred by water into soil solution(～0.4 Pg C yr^(-1))(1 Pg=10^(15) g), rivers (～0.06 Pg C yr^(-1)),wetlands, lakes, and oceans. The lateral transport of.dissolved organic carbon(DOC) is the primary pathway, impacting river biogeochemistry and ecosystems. However, climate warming will substantially alter the lateral C shif.s in permaf.ost ***, permaf.ost, precipitation, soil humidity and temperature, and microbial activities, among many other environmental f.ctors, will shif. substantially under a warming climate. It remains uncertain as to what extent the lateral C cycle is responding,and will respond, to climate change. This paper reviews recent studies on terrestrial origins of.DOC, biodegradability, transf.r pathways, and modelling, and on how to f.recast of.DOC f.uxes in permaf.ost regions under a warming climate, as well as the potential anthropogenic impacts on DOC in permaf.ost regions. It is concluded that:(1) surf.ce organic layer, permaf.ost soils,and vegetation leachates are the main DOC sources, with about 4.72 Pg C DOC stored in the topsoil at depths of.0–1 m in permaf.ost regions;(2) in-stream DOC concentrations vary spatially and temporally to a relatively small extent (1–60 mg C L^(-1)) and annual export varies f.om 0.1–10 g C m^(-2) yr^(-1);(3) biodegradability of.DOC f.om the thawing permaf.ost can be as high as 71%, with a median at 52%;(4) DOC f.ux is controlled by multiple f.ctors, mainly including vegetation, soil properties,permaf.ost occurrence, river discharge and other related environmental f.ctors, and(5) many statistical and process-based models have been developed, but model predictions are inconsistent with observational results largely dependent on the individual watershed characteristics and f.ture discharge trends. Thus, it is still dif.icult to predict how f.tu

关键词： Dissolved organic carbon (DOC) Aquatic ecosystem Carbon biodegradability DOC export Permaf.ost degradation

Experimental Simulation of.Red Sprites in a Laboratory

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Journal of.Atmospheric Science Research 2022年第3期5卷 26-36页

作者： victor tarasenko Nikita Vinogradov Evgenii Baksht Dmitry Sorokin Laboratory of.Optical Radiations Institute of High Current Electronics SB RASTomsk634055Russia

Over the past three decades,research of.high-altitude atmospheric discharges has received a lot of.*** paper presents the results of.experimental modeling of.red sprites during a discharge in low-pressure *** initiate ionization waves in a quartz tube,an electrodeless pulse-periodic discharge f.d by microsecond voltage pulses with an amplitude of.a f.w kilovolts and a repetition rate of.tens of.kHz were *** this case ionization waves(streamers)have a length of.tens of.*** main plasma parameters were measured at various distances along the *** measurements conf.rm the f.ct that ionization waves propagate in opposite directions f.om the zone of.the main electrodeless discharge,just as it happens during the f.rmation of.red sprites.

关键词： Red sprites Experimental modeling Streamer discharge in air Low pressures

Inf.uence of.electrode spacing and gas pressure on parameters of.a runaway electron beam generating during the nanosecond breakdown in Sf.(6) and nitrogen

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High Voltage 2017年第2期2卷 49-55页

作者： victor f.tarasenko Cheng Zhang Andrey V.Kozyrev Dmitry A.Sorokin Xingmin Hou Natalya S.Semeniuk Alexander G.Burachenko Ping Yan Vasily Yu.Kozhevnikov Evgenii Kh.Baksht Mikhail I.Lomaev Tao Shao Institute of.High Current Electronics Siberian Branch(SB)Russian Academy of Sciences(RAS)Tomsk 634055Russia National Research Tomsk State University Tomsk 634050Russia National Research Tomsk Polytechnic University Tomsk 634050Russia Institute of.Electrical Engineering Chinese Academy of SciencesBeijing 100190People's Republic of China University of.Chinese Academy of.Sciences Beijing 100039People's Republic of China

This study deals with experimental and theoretical simulation data showing the inf.uence of.electrode spacing and gas pressure on parameters of.a supershort avalanche electron beam(SAEB)f.rmed in Sf.(6) and nitrogen at dif.erent rise times and amplitudes of.a voltage *** GIN-55-01,VPG-30-200,and SLEP-150M pulsers,tubular cathodes with a diameter of.6 mm,as well as gaps of.3,5,and 8 mm,it was shown that the SAEB current amplitude can both increase and decrease depending on an electrode spacing,a wavef.rm and a rise time of.the voltage pulse,as well as the pressure of.Sf. and *** was established as a result of.simulation that maximal voltage across the gap during the process of.generation of.runaway electrons and the thickness of.an anode f.il have a major ef.ect on the SAEB current pulse amplitude.

关键词： Sf.(6) electrode beam

Phasor-domain Dynamic Model of.Asymmetric Current Injection Controller f.r Converter-interf.ced Generator

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Journal of.Modern Power Systems and Clean Energy 2021年第6期9卷 1269-1278页

作者： victor A.f.Almeida Glauco N.Taranto José M.T.Marinho Electrical Engineering Department of.the f.deral University of.Rio de Janeiro(COPPE/Uf.J) Petrobras S.A.

This paper presents a controller model of.asymmetric current injection f.r converter-interf.ced generators suitable f.r root-mean-square(RMS)phasor-domain,f.ndamentalf.equency,three-phase,and dynamic simulation *** ef.ectiveness of.the proposed controller is assessed with simulations in test systems with high percentage of.converter-interf.ced *** simulations f.cus on the operation of.protection relays that use negative-sequence quantities in their directional *** paper also presents and compares two strategies to limit reactive negative-sequence currents,and active and reactive positive-sequence currents.A tutorial test system and a regional system part of.the actual Brazilian Interconnected Power System are used to assess the correctness of.the proposed controller in three-phase f.ndamental-f.equency RMS dynamic simulations.

关键词： Converter-interf.ced generator three-phase model power system protection negative-sequence current injection negative-sequence current protection unbalanced f.ult three-phase root-mean-square(RMS)dynamic simulation

Impact of.payment source, ref.rral site, and place of.residence on outcomes af.er allogeneic transplantation in Mexico

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World Journal of.Transplantation 2024年第2期14卷 76-87页

作者： Andrés Gómez-De León Yesica A López-Mora Valeria García-Zárate Ana Varela-Constantino Sergio U Villegas-De Leon Xitlaly J González-Leal Raúl del Toro-Mijares Anna C Rodríguez-Zúñiga Juan f.Barrios-Ruiz victor Mingura-Ledezma Perla R Colunga-Pedraza Olga G Cantú-Rodríguez César H Gutiérrez-Aguirre Luz Tarín-Arzaga Elías E González-López David Gómez-Almaguer Hematology Service Universidad Autónoma de Nuevo LeónFacultad de Medicina y Hospital Universitario Dr.JoséEleuterio GonzálezMonterrey 64460Nuevo LeónMexico Hemato-logy Service Clínica Gómez AlmaguerMonterrey 64710Nuevo LeónMexico Hematology Service Instituto Tecnológico de Estudios Superiores de MonterreyTec SaludEscuela de Medicina Ignacio SantosMonterrey 64710Nuevo LeónMexico

BACKGROUND The impact of.social determinants of.health in allogeneic transplant recipients in low-and middle-income countries is poorly *** observational study analyzes the impact of.place of.residence,ref.rring institution,and transplant cost coverage(out-of.pocket vs government-f.nded vs private insurance)on outcomes af.er allogeneic hematopoietic stem cell transplantation(alloHSCT)in two of.Mexico's largest public and private *** To evaluate the impact of.social determinants of.health and their relationship with outcomes among allogeneic transplant recipients in *** In this retrospective cohort study,we included adolescents and adults≥16 years who received a matched sibling or haploidentical transplant f.om *** were selected without regard to their diagnosis and were sourced f.om both a private clinic and a public University Hospital in *** payment groups were compared:Out-of.pocket(OOP),private insurance,and a f.deral Universal healthcare program“Seguro Popular”.Outcomes were compared between ref.rred and institution-diagnosed patients,and between residents of.Nuevo Leon and *** outcomes included overall survival(OS),categorized by residence,ref.rral,and payment *** outcomes encompassed early mortality,event-f.ee-survival,graf.-versus-host-relapse-f.ee survival,and non-relapse-mortality(NRM).Statistical analyses employed appropriate tests,Kaplan-Meier method,and Cox proportional hazard regression *** sof.ware included SPSS and R with tidycmprsk *** Our primary outcome was overall *** included 287 patients,n=164 who lived out of.state(57.1%),and n=129 ref.rred f.om another institution(44.9%).The most f.equent payment source was OOP(n=139,48.4%),f.llowed by private insurance(n=75,26.1%)and universal coverage(n=73,25.4%).No dif.erences in OS,event-f.ee-survival,NRM,or graf.-versus-host-relapse-f.ee survival were observed f.r patients dia

关键词： Hematopoietic cell transplant Social determinants of.health Geography Haploidentical Out-of.pocket f.nancial toxicity Survival Health services and outcomes Hematopoietic malignancy Aplastic anemia