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Analysis of a passive ankle exoskeleton for reduction of metabolic costs during walking

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Defence Technology（防务技术） 2024年第7期37卷 62-68页

作者： Luís Quinto Pedro Pinheiro Sergio B.goncalves Ivo Roupa Paula Simoes Miguel Tavares da Silva CINAMIL Academia MilitarInstituto Universitario MilitarLisbonPortugal IDMEC Instituto Superior TecnicoUniversidade de LisboaLisbonPortugal

Modern conflicts demand substantial physical and psychological exertion,often resulting in fatigue and diminished combat or operational *** exoskeletons have been developed recently to address these challenges,presenting various limitations that affect their operational or everyday *** article evaluates the performance of a dual-purpose passive ankle exoskeleton developed for the reduction of metabolic costs during walking,seeking to identify a force element that could be applied to the target *** on the 6-min walk test,twenty-nine subjects participated in the study using three different force *** results indicate that it is possible to reduce metabolic expenditure while using the developed ***,the comfort and range of motion results verify the exoskeleton's suitability for use in uneven terrain and during extended ***,the choice of the force element should be tailored to each user,and the control system should be adjustable to optimise the exoskeleton's performance.

关键词： Ankle passive exoskeleton Metabolic cost reduction Dual-use exoskeleton Gait Biomechanics

Numerical Analysis for Transients in External Source Driven Reactors

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World Journal of Nuclear Science and Technology 2017年第2期7卷 103-120页

作者： Willian Vieira de Abreu alessandro da cruz goncalves Zelmo Rodrigues de Lima Nuclear Engineering Institute National Commission for Nuclear EnergyRio de JaneiroBrazil Nuclear Engineering Program COPPEFederal University of Rio de Janeiro/UFRJRio de JaneiroBrazil

The main purpose of this paper is to perform a numerical analysis of the Neutron Spatial Kinetic Equations, subject to transients of the External Neutron Source, by applying the Implicit Euler Method as well as the Runge-Kutta Method in order to check which methods are best applicable in transients caused by External Neutron Source. For this purpose, a one-dimensional ADS reactor with a constant external source was simulated based on the geometry of ANL-BSS-6 reactor for benchmark effects.

关键词： ADS Transients Spatial Kinetics

Analytical solution of modified point kinetics equations for linear reactivity variation in subcritical nuclear reactors adopting an incomplete gamma function approximation

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Natural Science 2012年第11期4卷 919-923页

作者： André Luiz Pereira Rebello Junior Aquilino Senra Martinez alessandro da cruz goncalves Nuclear Engineering Department Federal University of Rio de Janeiro Rio de Janeiro Brazil

The present work aims to achieve a fast and accurate analytical solution of the point kinetics equations applied to subcritical reactors such as ADS (Accelerator-Driven System), assuming a linear reactivity and external source variation. It was used a new set of point kinetics equations for subcritical systems based on the model proposed by Gandini & Salvatores. In this work it was employed the integrating factor method. The analytical solution for the case of interest was obtained by using only an approximation which consists of disregarding the term of the second derivative for neutron density in relation to time when compared with the other terms of the equation. And also, it is proposed an approximation for the upper incomplete gamma function found in the solution in order to make the computational processing faster. In addition, for purposes of validation and comparison a numerical solution was obtained by the finite differences method. Finally, it can be concluded that the obtained solution is accurate and has fast numerical processing time, especially when compared with the results of numerical solution by finite difference. One can also observe that the gamma approximation used achieve a high accuracy for the usual parameters. Thus we got satisfactory results when the solution is applied to practical situations, such as a reactor startup.

关键词： Accelerator-Driven System Subcritical Reactors Point Kinetics Equations Incomplete Gamma Functions

What is the effect of Tribulus terrestris on testicular morphology and sperm production?An experimental study in the rat model

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Asian Journal of Andrology 2024年第1期26卷 67-70页

作者： Marcello Henrique Araujo da Silva Gabriela Faria Buys-goncalves Joao Henrique Duque Reis Estrada Francisco Jose Barcellos Sampaio Diogo Benchimol de Souza Urogenital Research Unit Rio de Janeiro State UniversityRio de Janeiro 20551-030RJBrazil

The objective of this study was to investigate whether treatment with Tribulus terrestris(Tt)has any impact on the testicular morphology and function in a rodent *** male rats were divided into a control group and a group receiving 100 mg kg^(-1) body weight of Tt *** 4o days of experiment,the animals were submitted to euthanasia;epididymal tail spermatozoa were collected;and spermatozoa concentration,motility,and viability were *** addition,testicles were collected and processed for histomorphometrical *** were compared using the Student's t-test and considered significant when P<*** concentration,motility,and viability showed no difference between the ***,testicular weight and volume,seminiferous tubule diameter,tunica propria surface density,seminiferous epithelium surface density,and intertubular compartment surface density were statistically similar between the ***,seminiferous epithelium height and tubular lumen surface density were augmented in animals treated with *** with Tt does not cause a major impact on testicular morphology,promoting only subtle *** difference on spermatozoa parameters was observed.

关键词： morphometry testicle Tribulus terrestris

Artificial intelligence and inflammatory bowel disease: Where are we going?

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World Journal of Gastroenterology 2023年第3期29卷 508-520页

作者： Leonardo da Rio Marco Spadaccini Tommaso Lorenzo Parigi Roberto Gabbiadini Arianna dal Buono Anita Busacca Roberta Maselli alessandro Fugazza Matteo Colombo Silvia Carrara Gianluca Franchellucci Ludovico Alfarone Antonio Facciorusso Cesare Hassan alessandro Repici alessandro Armuzzi Department of Endoscopy Humanitas Research HospitalIRCCSRozzano 20089MilanoItaly Department of Biomedical Sciences Humanitas UniversityRozzano 20089MilanoItaly IBD Center Humanitas Research HospitalIRCCSRozzano 20089MilanoItaly Gastroenterology Unit Department of Medical SciencesUniversity of FoggiaFoggia 71122FoggiaItaly

Inflammatory bowel diseases,namely ulcerative colitis and Crohn’s disease,are chronic and relapsing conditions that pose a growing burden on healthcare systems *** of their complex and partly unknown etiology and pathogenesis,the management of ulcerative colitis and Crohn’s disease can prove challenging not only from a clinical point of view but also for resource *** intelligence,an umbrella term that encompasses any cognitive function developed by machines for learning or problem solving,and its subsets machine learning and deep learning are becoming ever more essential tools with a plethora of applications in most medical *** this regard gastroenterology is no exception,and due to the importance of endoscopy and imaging numerous clinical studies have been gradually highlighting the relevant role that artificial intelligence has in inflammatory bowel diseases as *** aim of this review was to summarize the most recent evidence on the use of artificial intelligence in inflammatory bowel diseases in various contexts such as diagnosis,follow-up,treatment,prognosis,cancer surveillance,data collection,and ***,insights into the potential further developments in this field and their effects on future clinical practice were discussed.

关键词： Inflammatory bowel disease Artificial intelligence Machine learning Crohn’s disease Ulcerative colitis Computer-aided diagnosis

Antiglycation and antioxidant activities of the crude extract and saponin fraction of Tribulus terrestris before and after microcapsule release

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Journal of Integrative Medicine 2022年第2期20卷 153-162页

作者： Célia Cristina Malaguti Figueiredo Amanda da Costa Gomes Filipe Oliveira Granero Joao Luiz Bronzel Junior Luciana Pereira Silva Valdecir Farias Ximenes Regildo Márcio goncalves da Silva Institute of Chemistry São Paulo State UniversityAraraquaraSão Paulo 14800-060Brazil Educational Foundation of the City of Assis AssisSão Paulo 19807-130Brazil Department of Chemistry School of SciencesSão Paulo State UniversityBauruSão Paulo 17033-360Brazil Department of Biotechnology School of SciencesHumanities and LanguagesSão Paulo State UniversityAssisSão Paulo 19806-900Brazil

Objective:The present study investigated antiglycation and antioxidant activities of crude dry extract and saponin fraction of Tribulus *** also developed a method of microencapsulation and evaluated antiglycation and antioxidant activities of crude dry extract and saponin fraction before and after microcapsule ***:Antiglycation activity was determined by relative electrophoretic mobility(REM),free amino groups and inhibition of advanced glycation end-product(AGE)*** activity was determined by 2,2-diphenyl-1-picrylhydrazyl(DPPH),ferric ion-reducing antioxidant power(FRAP),nitric oxide(NO)and thiobarbituric acid reactive species(TBARS)*** were prepared using maltodextrin as wall material and freeze-drying as encapsulation *** characterization of microcapsules was evaluated by scanning electron microscopy,and encapsulation efficiency and microcapsule release were determined by total saponins *** and antioxidant assays were performed using crude dry extract and saponin fraction of *** before and after ***:Saponin fraction showed an increase of 32.8%total ***-performance liquid chromatography-mass spectrometry analysis showed the presence of saponins in the obtained *** evaluation by REM demonstrated that samples before and after release presented antiglycation activity similar to bovine serum albumin treated with ***,samples inhibited AGE formation,highlighting treatment with saponin fraction after release(89.89%).Antioxidant tests demonstrated antioxidant activity of the *** dry extract before encapsulation presented the highest activities in DPPH(92.00%)and TBARS(32.49%)*** fraction before encapsulation in FRAP test(499μmol Trolox equivalent per gram of dry sample)and NO test(15.13μmol nitrite formed per gram of extract)presented the highest ***:This study presen

关键词： Glycation Microencapsulation Oxidative stress Saponins Tribulus terrestris

Short-term effect of physical activity on sleep health:A population-based study using accelerometry

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Journal of Sport and Health Science 2022年第5期11卷 630-638页

作者： Andrea Wendt Inácio Crochemore M.da Silva Helen goncalves Ana Menezes Fernando Barros Fernando C.Wehrmeister Post-graduate Program in Epidemiology Federal University of PelotasPelotas 96020-220Brazil

Background:Regular physical activity(PA) is an important behavior in improving sleep ***,the short-term effects of PA on sleep are still *** study aimed to verify the effect of different intensities of PA practiced in different periods of the day on the subsequent sleep night in a population-based cohort of young ***::Prospective analyses were conducted for PA performed during the day and its effect on the following sleep night using data from the22-year follow-up of the 1993 Pelotas Birth Cohort in Brazil(mean age of participants-22.6 years).Wrist-worn accelerometry was usedto measure both PA and sleep *** intensity,we analyzed the sleep effect of light PA(LPA),moderate PA,and vigorous PA,stratified by *** variables were sleep time window(STW;the difference between sleep onset and sleep end),total sleep time(TST;the sum of minutes classified as sleep in STW),and sleep percent(SP;SP=(TST/STW);expressed in percentage).We performed generalized estimating equations using Stata ***::The means of STW,TST,and SP were 443.6 min/day,371.1 min/day,and 84%,*** spent in moderate PA and vigorous PA in the morning and afternoon was not associated with sleep *** men,10 min/day of morning LPA increased TST by2.56 min/*** women,10 min/day of morning LPA increased SP by 0.15 percentage *** LPA also increased SP by 0.09 percentage points for *** PA seems to have an inverse effect on sleep variables for any intensity and both ***::The effect of PA on sleep health is intrinsically related to the period of the day in which it is *** effect magnitude is different between *** better sleep health,it is preferable that PA be performed during the day.

关键词： Accelerometer Exercise Physical activity Population-based study Sleep health

Movement behaviors and their association with depressive symptoms in Brazilian adolescents:A cross-sectional study

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Journal of Sport and Health Science 2022年第2期11卷 252-259页

作者： Bruno goncalves Galdino da Costa Jean-Philippe Chaput Marcus Vinicius Veber Lopes Luis Eduardo Argenta Malheiros Kelly Samara Silva Research Centre in Physical Activity and Health Federal University of Santa CatarinaFlorianopolis88040-900Brazil Healthy Active Living and Obesity Research Group Children’s Hospital of Eastern Ontario Research InstituteOttawaON K1H 8L1Canada

Background:Physical activity,sleep,and sedentary behaviors compose 24-h movement behaviors and have been independently associated with depressive ***,it is not clear whether it is the movement behavior itself or other contextual factors that are related to depressive *** objective of the present study was to examine the associations between self-reported and accelerometer-measured movement behaviors and depressive symptoms in ***:Cross-sectional data from 610 adolescents(14-18 years old)were *** answered questions from the Center for Epidemiological Studies Depression scale and reported time spent watching videos,playing videogames,using social media,time spent in various physical activities,and daytime ***-worn accelerometers were used to measure sleep duration,sleep efficiency,sedentary time,and physical ***-effects logistic regressions were ***:Almost half of the adolescents(48%)were classified as being at high risk for depression(score≥20).No significant associations were found between depressive symptoms and accelerometer-measured movement behaviors,self-reported non-sport physical activity,watching videos,and playing ***,higher levels of self-reported total physical activity(odd ratio(OR)=0.92,95%confidence interval(95%CI):0.86-0.98)and volume of sports(OR=0.88,95%CI:0.79-0.97),in minutes,were associated with a lower risk of depression,while using social media for either 2.0-3.9 h/day(OR=1.77,95%CI:1.58-2.70)or>3.9 h/day(OR=1.67,95%CI:1.10-2.54),as well as higher levels of daytime sleepiness(OR=1.17,95%CI:1.12-1.22),were associated with a higher risk of ***:What adolescents do when they are active or sedentary may be more important than the time spent in the movement behaviors because it relates to depressive *** daytime sleepiness,promoting sports,and limiting social media use may benefit adolescents.

关键词： Accelerometry Depression Physical activity Sedentary behavior Sleep

Cell membrane and bioactive factors derived from mesenchymal stromal cells: Cell-free based therapy for inflammatory bowel diseases

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World Journal of Stem Cells 2019年第9期11卷 618-633页

作者： Fabiany da Costa goncalves Ana Helena Paz Nephrology and Transplantation Internal MedicineErasmus Medical CenterRotterdamGD 3015Netherlands Experimental Research Center Hospital de Clínicas de Porto AlegrePorto AlegreRS 90035-903Brazil

Inflammatory bowel diseases(IBD)are chronic inflammatory disorders of the gastrointestinal tract associated with multifactorial conditions such as ulcerative colitis and Crohn’s *** the underlying mechanisms of IBD remain unclear,growing evidence has shown that dysregulated immune system reactions in genetically susceptible individuals contribute to mucosal ***,conventional treatments have been effective in inducing remission of IBD but not in preventing the relapse of *** this way,mesenchymal stromal cells(MSC)therapy has been recognized as a promising treatment for IBD due to their immunomodulatory properties,ability to differentiate into several tissues,and homing to inflammatory *** so,literature is conflicted regarding the location and persistence of MSC in the body after *** this reason,recent studies have focused on the paracrine effect of the biofactors secreted by MSC,especially in relation to the immunomodulatory potential of soluble factors(cytokines,chemokines,and growth factors)and extracellular vehicles that are involved in cell communication and in the transfer of cellular material,such as proteins,lipids,and nucleic ***,treatment with interferon-γ,tumor necrosis factor-α,and interleukin-1βcauses MSC to express immunomodulatory molecules that mediate the suppression via cell-contact dependent *** together,we present an overview of the role of bioactive factors and cell membrane proteins derived from MSC as a cell-free therapy that can improve IBD treatment.

关键词： Bioactive factors Cell membrane Mesenchymal stem cells Cell-free therapy Inflammatory bowel diseases