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Acta Metallurgica Sinica(English Letters) 2019年第6期32卷 695-709页

作者： andre barros Clarissa Cruz Adrina P.Silva Noe Cheung Amauri Garcia Otavio Rocha Antonio Moreira Institute of Technology Federal University of Para-UFPABelemPA 66075-110Brazil Federal Institute of Education Science and Technology of Para-IFPABelemPA 66093-020Brazil Department of Manufacturing and Materials Engineering University of Campinas-UNICAMPCampinasSP 13083-860Brazil

In the present experimental investigation,Al–3 wt%Cu and Al–3 wt%Cu–0.5 wt%Mg alloys castings are produced by a horizontal solidification technique with a view to examining the interrelationship among growth rate(GR),cooling rate(CR),secondary dendrite arm spacing(λ2),Vickers microhardness(HV),and corrosion behavior in a 0.5 M NaCl *** intermetallic phases of the as-solidified microstructures,that is,h-Al2Cu,S–Al2CuMg,and x-Al7Cu2 Fe,are subjected to a comprehensive characterization by using calculations provided by computational thermodynamics software,optical microscopy,and scanning electron microscopy/energy-dispersive ***,electrochemical impedance spectroscopy and potentiodynamic polarization tests have been applied to analyze the corrosion performance of samples of both alloys ***–Petch-type equations are proposed to represent the HV dependence onλ*** is shown that the addition of Mg to the Al–Cu alloy has led to a considerable increase in HV;however,the Al–Cu binary alloy is shown to have lower corrosion current density(icorr)as well as higher polarization resistance as compared to the corresponding results of the Al–Cu–Mg ternary alloy.

关键词： Aluminum alloys Solidification Dendritic microstructure Intermetallic phases Microhardness Corrosion resistance

Perianal disease in inflammatory bowel disease:Broadening treatment and surveillance strategies for anal cancer

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World Journal of Gastroenterology 2024年第28期30卷 3373-3385页

作者： Tatiana Pacheco Sara Monteiro Luísa barros Jorge Silva Department of Gastroenterology Centro Hospitalar do Tamega e SousaPenafiel 4560-136Portugal

The perianal disease affects up to one-third of individuals with Crohn's disease(CD),causing disabling symptoms and significant impairment in quality of life,particularly for those with perianal fistulising CD(PFCD).The collaborative effort between gastroenterologists and surgeons is essential for addressing PFCD to achieve fistula closure and promote luminal *** fistula healing rates with conventional therapies have prompted the emergence of new biological agents,endoscopic procedures and surgical techniques that show promising *** these,mesenchymal stem cells injection is a particularly hopeful *** addition to the burden of fistulas,individuals with perianal CD may face an increased risk of developing anal *** underscores the importance of surveillance programmes and timely interventions to prevent late diagnoses and poor ***,there is no established formal anal screening *** this review,we provide an overview of the current state of the art in managing PFCD,including novel medical,endoscopic and surgical *** discussion also focuses on the relevance of establishing an anal cancer screening programme in CD,intending to propose a risk-based surveillance *** validation of this surveillance programme would be a significant step forward in improving patient care and outcomes.

关键词： Inflammatory bowel disease Crohn's disease Perianal Fistula Anus diseases Management Anal cancer Screening

Investigation and optimization of high-valent Ta-doped SrFeO_(3-δ)as air electrode for intermediate-temperature solid oxide fuel cells

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International Journal of Minerals,Metallurgy and Materials 2024年第9期31卷 2102-2109页

作者： Shanshan Jiang Hao Qiu Shaohua Xu Xiaomin Xu Jingjing Jiang Beibei Xiao Paulo Sérgio barros Juliao) Chao Su Daifen Chen Wei Zhou School of Energy and Power Jiangsu University of Science and TechnologyZhenjiang 212100China WA School of Mines:Minerals Energy and Chemical EngineeringCurtin UniversityPerth WA6102Australia Institute of Analysis and Testing Beijing Academy of Science and TechnologyBeijing 100089China State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemical EngineeringNanjing Tech UniversityNanjing 211816China

To explore highly active and thermomechanical stable air electrodes for intermediate-temperature solid oxide fuel cells(ITSOFCs),10mol%Ta5+doped in the B site of strontium ferrite perovskite oxide(SrTa_(0.1)Fe_(0.9)O_(3-δ),STF)is investigated and *** effects of Ta^(5+)doping on structure,transition metal reduction,oxygen nonstoichiometry,thermal expansion,and electrical performance are evaluated *** 10mol%Ta^(5+)doping,the thermal expansion coefficient(TEC)decreased from 34.1×10^(-6)(SrFeO_(3-δ))to 14.6×10^(-6) K^(-1)(STF),which is near the TEC of electrolyte(13.3×10^(-6) K^(-1) for Sm_(0.2)Ce_(0.8)O_(1.9),SDC),indicates excellent thermomechanical *** 550-750℃,STF shows superior oxygen vacancy concentrations(0.262 to 0.331),which is critical in the oxygen-reduction reaction(ORR).Oxygen temperature-programmed desorption(O_(2)-TPD)indicated the thermal reduction onset temperature of iron ion is around 420℃,which matched well with the inflection points on the thermos-gravimetric analysis and electrical conductivity *** 600℃,the STF electrode shows area-specific resistance(ASR)of 0.152Ω·cm^(2) and peak power density(PPD)of 749 mW·cm^(-2).ORR activity of STF was further improved by introducing 30wt%Sm_(0.2)Ce_(0.8)O_(1.9)(SDC)powder,STF+SDC composite cathode achieving outstanding ASR value of 0.115Ω·cm2 at 600℃,even comparable with benchmark cobalt-containing cathode,Ba_(0.5)Sr_(0.5)Co_(0.8)Fe_(0.2)O_(3-δ)(BSCF).Distribution of relaxation time(DRT)analysis revealed that the oxygen surface exchange and bulk diffusion were improved by forming a composite *** 650℃,STF+SDC composite cathode achieving an outstanding PPD of 1117 mW·cm^(-2).The excellent results suggest that STF and STF+SDC are promising air electrodes for IT-SOFCs.

关键词： strontium ferrite-based perovskite Ta doping composite cathode intermediate-temperature solid oxide fuel cells

Sustainable Urban Mobility: (A)Synchrony between Subway Systems

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Journal of Traffic and Transportation Engineering 2024年第3期12卷 151-161页

作者： Ana Paula Borba Gonçalves barros University of Brasilia Brasilia 70910-900Brazil

The present study analyses the differences between the subways systems of two cities, Lisbon (Portugal) and Brasília (Brazil), verifying the extent to which their subway systems are spatially integrated with the respective urban fabric-which would promote a better synchrony in terms of economy and sustainability. For interpreting the data, the methodology and tools of the Theory of the Social Logic of Space were used, by means of axial maps, researching the relationship between the constructed and empty (public spaces) areas of the urban structures. Based on the findings, meaningful differences between the subway systems and the configuration of urban spaces were observed, as a product of specific design matrixes. In Lisbon, the mobility associated to the subway seems to be encouraged by the integration of the system with the potential for movement provided by the urban tissue (making the secondary centralities articulated with the subway stations more dynamic). In Brasilia, however, there are several difficulties for such mobility, due to the predominant role of the empty spaces in the city which weakens the gathering potential of such areas, despite the fact that such articulation with secondary centralities is also present there.

关键词： Urban mobility spatial configuration space syntax subway system.

Cerebral and muscle tissue oxygenation during exercise in healthy adults: A systematic review

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Journal of Sport and Health Science 2024年第4期13卷 459-471,F0003页

作者： Diego Orcioli-Silva Victor Spiandor Beretta Paulo Cezar Rocha Santos Felipe Marroni Rasteiro Anita Brum Marostegan Rodrigo Vitorio Claudio Alexandre Gobatto Fulvia barros Manchado-Gobatto Laboratory of Applied Sport Physiology(LAFAE) School of Applied Sciences(FCA)University of Campinas(UNICAMP)Limeira 13484-350Brazil Posture and Gait Studies Laboratory(LEPLO) Institute of BiosciencesSao Paulo State University(UNESP)Rio Claro 13506-900Brazil Physical Education Department School of Technology and SciencesSao Paulo State University(UNESP)Presidente Prudente 19060-900Brazil Department of Computer Science&Applied Mathematics Weizmann Institute of ScienceRehovot 7610001Israel Center of Advanced Technologies in Rehabilitation Sheba Medical CenterRamat Gan 5265601Israel Department of Sport Exercise and RehabilitationNorthumbria UniversityNewcastle upon Tyne NE18STUK

Background:Near-infrared spectroscopy(NIRS)technology has allowed for the measurement of cerebral and skeletal muscle oxygenation simultaneously during *** this technology has been growing and is now successfully used in laboratory and sports settings,this systematic review aimed to synthesize the evidence and enhance an integrative understanding of bloodﬂow adjustments and oxygen(O_(2))changes(i.e.,the balance between O_(2) delivery and O_(2) consumption)within the cerebral and muscle systems during ***:A systematic review was conducted using PubMed,Embase,Scopus,and Web of Science databases to search for relevant studies that simultaneously investigated cerebral and muscle hemodynamic changes using the near-infrared spectroscopy system during *** review considered manuscripts written in English and available before February 9,*** step of screening involved evaluation by 2 inde-pendent authors,with disagreements resolved by a third *** Joanna Briggs Institute Critical Appraisal Checklist was used to assess the methodological quality of the ***:Twenty studies were included,of which 80%had good methodological quality,and involved 290 young or middle-aged *** types of exercises were used to assess cerebral and muscle hemodynamic changes,such as cycling(n=11),treadmill(n=1),knee extension(n=5),isometric contraction of biceps brachii(n=3),and duet swim routines(n=1).The cerebral hemodynamics anal-ysis was focused on the frontal cortex(n=20),while in the muscle,the analysis involved vastus lateralis(n=18),gastrocnemius(n=3),biceps brachii(n=5),deltoid(n=1),and intercostal muscle(n=1).Overall,muscle deoxygenation increases during exercise,reaching a plateau in voluntary exhaustion,while in the brain,oxyhemoglobin concentration increases with exercise intensity,reaching a plateau or declining at the exhaustion ***:Muscle and cerebral oxygenation respond differently to exercise,with muscle

关键词： Near-infrared spectroscopy Hemodynamic Blood flow Brain Muscle metabolism

Characterization of Arroyo Verde Epithermal Deposit:Paragenesis,Mineral Geochemistry,Geochronology and Fluid Inclusions in Lower Chon Aike Volcanism,Argentina

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Journal of Earth Science 2024年第1期35卷 62-84页

作者： Cecilia Pavón Pivetta Leonardo Benedini Paulo Marcos Ma.Agustina Cócola Mercedes Virginia barros Daniel Gregori Leonardo Strazzere Anderson Costa dos Santos Mauro C.Geraldes Instituto Geologico del Sur(INGEOSUR) Universidad Nacional del Sur(UNS)-Consejo Nacional de Investigaciones Cientificas y Tecnicas(CONICET)Bahia Blanca 8000Argentina Dpto.de Geologia Universidad Nacional del Sur(UNS)Bahia Blanca 8000Argentina Universidad Nacional de Rio Negro Instituto de Investigacion en Paleobiologia y GeologiaGeneral Roca 8332Argentina Universidade do Estado do Rio de Janeiro Faculdade de GeologiaDepartamento de Mineralogia e Petrologia igneaRiodeJaneiro20559-900Brazil Geobiotec Departamento de GeocienciasUniversidade de AveiroAveiro 3800-002Portuga

Arroyo Verde epithermal deposit,in the North Patagonia region of Argentina,is located within the Lower Chon Aike volcanism and is developed between 192.6±2.5 Ma(mineralization host rock)and 189.5±2.6 Ma(overlying lava).Marifil volcanic complex is the host rock for these veins,veinlets and *** particular small deposit has developed low to intermediate sulphidation characteristics,with gangue mineral textures associated with several ore *** probe microanalysis determines electrum,silver minerals such as acanthite,and tetrahedrite,related Ag-Cu minerals like jalpaite,mckinstryite,stromeyerite,and base metals like chalcopyrite,sphalerite,galena and *** inclusions in quartz of two out of five events indicate that these Low Jurassic veins were formed due to subtle boiling and dilution mechanisms and by low-salinity(3.4 wt.%to 6.7 wt.%NaCl Eq)magmatic-hydrothermal fluid at 225 to 310℃.The fluid inclusion measurements that indicate boiling(Event 3)were plotted,and based on this data,we interpret that the Arroyo Verde deposit has been eroded between 550 and 700 *** particular character has not been previously recorded for other sectors of the eastern north Patagonian region.

关键词： epithermal deposit Ag minerals mineral geochemistry fluid inclusions Chon Aike geochronology

Study of the Conversion of Postconsumer Polystyrene on CeO₂/HZSM-5 Type Materials

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Journal of Materials Science and Chemical Engineering 2024年第4期12卷 29-41页

作者： Mirna Oliveira Sant’Ana Anne Michelle Garrido Pedrosa Marcelo José barros de Souza Graduate Program in Chemical Engineering at UFS Federal University of Sergipe (UFS) S&#227o Crist&#243v&#227o Brazil Department of Chemistry Federal University of Sergipe S&#227o Crist&#243v&#227o Brazil

The catalytic conversion of polystyrene (PS) was studied in the presence of the materials type HZSM-5, CeO2, 10% CeO2/HZSM-5 and 20% CeO2/HZSM-5, which were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and nitrogen adsorption at 77K. The catalytic tests were performed via thermogravimetric analysis (TG) at heating rates of 5, 10 and 20˚C min−1 in a temperature range from 30˚C to 900˚C. For the tests, a ratio of 30% by mass of each catalytic material mixed with PS was used and the activation energy of the degradation process was determined by the Vyazovkin method. The obtained results showed that the addition of the catalyst to the PS in general reduced its degradation temperature. The 10% CeO2/HZSM-5 catalyst showed greater efficiency, as it resulted in lower activation energy for PS degradation. Thus, the combination of CeO2 with HZSM-5 resulted in materials with potential for application in the catalytic degradation of polystyrene and the results indicate that the production of a composite material can be a good strategy to generate an increase in catalytic activity and a decrease in energy process activation.

关键词： HZSM-5 Zeolite Cerium Oxide Polystyrene Pyrolysis

Complexed amino acid minerals vs. bis-glycinate chelated minerals:Impact on the performance of old laying hens

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Animal Nutrition 2024年第1期16卷 395-408页

作者： Marcos J.B.Santos Maria C.M.M.Ludke Leandro M.Silva Carlos B.V.Rabello Mércia R.barros Fabiano S.Costa Clariana S.Santos Jamille S.S.Wanderley Department of Animal Science Rural Federal University of Pernambuco Department of Veterinary Science Rural Federal University of Pernambuco

The present study was to evaluate the effect of trace minerals(Zn, Mn, and Cu) from complexed amino acid minerals(ZMCAA) and bis-glycinate chelated minerals(ZMCGly) in laying hen diets on performance,internal and external egg quality, yolk mineral deposition, intestinal morphometry, and bone characteristics. From 78 to 98 weeks of age, 400 White LSL-Lite strain laying hens were distributed in a randomized design with 4 treatments with 10 replicates per treatment. Treatments were distributed in a 2 ×2 factorial arrangement using either Zn, Mn, and Cu of ZMCAA or ZMCGly source at 2 levels: low(20, 20,and 3.5 mg/kg of Zn, Mn, and Cu, respectively) or high(40, 40, and 7 mg/kg of Zn, Mn, and Cu,respectively). The analysis of variance was performed, and in cases where differences were observed, the means were compared using Tukey?s test(P < 0.05). The source and level of trace mineral supplementation had a significant impact on the performance of laying hens. Hens fed ZMCAA had higher egg production(P = 0.01), egg weight(P = 0.02), egg mass(P = 0.01), and lower feed conversion ratio(P =0.05) compared to those fed ZMCGly. The ZMCAA supplementation showed higher albumen height(P =0.01), albumen weight(P = 0.01), and eggshell thickness(P < 0.01). The deposition of Zn(P < 0.01), Mn(P< 0.01), and Cu(P < 0.01) in the egg yolk was greater for hens received ZMCAA. Tibia weight(P = 0.04)and bone densitometry(P < 0.01) in the tibia were higher with ZMCAA supplementation. In the small intestine, ZMCAA resulted in longer villi(P = 0.02) and shorter crypt depth(P = 0.01) in the *** and ileum measurements were influenced by the level and source of trace minerals(P < 0.05).Laying hens fed ZMCAA exhibited superior performance, egg quality, deposition of trace minerals in the egg yolk, and bone density compared to hens fed ZMCGly. In this study, older laying hens supplemented with ZMCAA at lower levels demonstrated adequate levels of supplementation.

关键词： Bis-glycinates Metal-amino acids Radiodensity Trace minerals

Analysing vaccine efficacy evaluated in phase 3 clinical trials carried out during outbreaks

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Infectious Disease Modelling 2024年第4期9卷 1027-1044页

作者： Francisco Antonio Bezerra Coutinho Marcos Amaku Fernanda Castro Boulos Jose Alfredo de Sousa Moreira Joao Italo DiasFranca Julio Antonio do Amaral Eliana Nogueira Castro de barros Claudio Jose Struchiner Esper Jorge Kallas Eduardo Massad School of Medicine University of Sao PauloBrazil Instituto Butantan Sao PauloBrazil School of Applied Mathematics Fundacao Getulio VargasRio de JaneiroBrazil

In this paper we examine several definitions of vaccine efficacy(VE)that we found in the literature,for diseases that express themselves in outbreaks,that is,when the force of infection grows in time,reaches a maximum and then *** fact that the disease occurs in outbreaks results in several problems that we *** propose a mathematical model that allows the calculation of VE for several *** trials usually needs a large number of volunteers that must be ***,all volunteers should be enrolled in approximately the same time,but this is generally impossible for logistic reasons and they are enrolled in a fashion that can be replaced by a continuous density function(for example,a Gaussian function).The outbreak can also be replaced by a continuous density function,and the use of these density functions simplifies the ***,for example Gaussian functions,one of the problems one can immediately notice is that the peak of the two curves do not occur at the same *** model allows us to conclude:First,the calculated vaccine efficacy decreases when the force of infection increases;Second,the calculated vaccine efficacy decreases when the gap between the peak in the force of infection and the peak in the enrollment rate increases;Third,different trial protocols can be simulated with this model;different vaccine efficacy definitions can be calculated and in our simulations,all result are approximately the *** final,and perhaps most important conclusion of our model,is that vaccine efficacy calculated during outbreaks must be carefully examined and the best way we can suggest to overcome this problem is to stratify the enrolled volunteer's in a cohort-by-cohort basis and do the survival analysis for each cohort,or apply the Cox proportional hazards model for each cohort.

关键词： Vaccine efficacy Clinical trials Mathematical models Simulations Covid-19

A single session of strength training changed plasma levels of resistin,but not leptin in overweight and obese men

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Sports Medicine and Health Science 2024年第4期6卷 324-330页

作者： Yago Martins Fortes Antonio Felipe Souza-Gomes Alessandro Roberto Silveira Moreira Leo Nogueira Campos Samara Silva de Moura Lucelia Scarabeli Silva barroso Marcelo Henrique Salviano de Faria Heliana de barros Fernandes Aline Silva de Miranda Hugo Cesar Martins-Costa Ana Cristina Simoes e Silva Janaina Matos Moreira Albena Nunes-Silva Laboratory of Inflammation and Exercise Immunology Department of Physical EducationSchool of Physical EducationFederal University of Ouro PretoOuro PretoMGBrazil Postgraduate Program in Health and Nutrition Nutrition SchoolFederal University of Ouro PretoOuro PretoMGBrazil Interdisciplinary Medical Research Laboratory Faculty of MedicineFederal University of Minas GeraisBelo HorizonteMGBrazil Neurobiology Laboratory Institute of Biological SciencesFederal University of Minas GeraisBelo HorizonteMGBrazil Department of Physical Education Pontifical Catholic University of Minas GeraisBrazil Department of Pediatrics Faculty of MedicineFederal University of Minas Gerais(UFMG)Belo HorizonteMGBrazil

Obesity has a complex multifactorial etiology and is characterized by excessive accumulation of adipose *** adipose tissue has deleterious effects on health because it secretes large amounts of inflammatory *** calorie restriction associated with strength training may be useful in managing chronic systemic *** study aimed to evaluate the acute effect of a single strength-training session on plasma adipokine levels in sedentary,overweight,and obese young *** study included twelve men(Age:[34.95±9.77]years;Height:[174.16±3.66]centimeter[cm];Weight:[97.83±12.87]kilogram(kg);body mass index[BMI]:[32.30±4.51]kg/m2),who performed a single strength training *** strength training protocol consisted of 4 sets of 12 repetitions in the following six exercises,45°leg press,bench press,leg extension,machine row,leg curl,and shoulder *** samples were collected before,immediately after,and 1-h subsequent after strength *** plasma levels of resistin and leptin were measured.A significant decrease in resistin levels were found 1 h after the strength training session if compared to levels before the training session(pre-[before][2390±1199]picograms per milliliter[pg/mL]vs post-1 h[1-h subsequent][1523±798],6 pg/mL,p=0.0028).The plasma leptin levels did not differ at any time *** conclusion,a very well controlled single session of strength training significantly decreased the plasma levels of resistin without altering the concentration of leptin in overweight and obese *** effect,at least in part,supports the benefits of exercise by reducing the low grade inflammation and insulin resistance in obesity.

关键词： Strength training Adipose tissue Obesity Chronicinflammation Resistin Leptin