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Investigation of Galactic open cluster remnants： the case of NGC 7193

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Research in Astronomy and Astrophysics 2017年第1期17卷 31-54页

作者： Mateus de souza Angelo joao francisco Coelho dos Santos Jr Wagner Jose barbosa Corradi francisco ferreira de souza Maia Andres Eduardo Piatti Departamento de fisica ICEx Universidade Federal de Minas Gerais Av. Antonio Carlos 6627 31270-901 Belo Horizonte MG Brazil Observatorio Astronomico Universidad Nacional de Cordoba Laprida 854 5000 Cordoba Argentina Consejo Nacional de Investigaciones Cientificas y Tecnicas Av. Rivadavia 1917 C1033AAJ Buenos AiresArgentina

Galactic open clusters （OCs） that survive the early gas-expulsion phase are gradually de- stroyed over time by the action of disruptive dynamical processes. Their final evolutionary stages are characterized by a poorly populated concentration of stars called an open cluster remnant （OCR）. This study is devoted to assessing the real physical nature of the OCR candidate NGC 7193. GMOS/Gemini spectroscopy of 53 stars in the inner target region were obtained to derive radial velocities and at- mospheric parameters. We also employed photometric and proper motion data. The analysis method consists of the following steps：（i） analysis of the statistical resemblance between the cluster and a set of field samples with respect to the sequences defined in color-magnitude diagrams （CMDs）; （ii） a 5-dimensional iterative exclusion routine was employed to identify outliers from kinematical and posi- tional data; （iii） isochrone fitting to thes× （J - Ks） CMD of the remaining stars and the dispersion of spectral types along empirical sequences in the （J - H） × （H - Ks） diagram were checked. A group of stars was identified for which the mean heliocentric distance is compatible with that obtained via isochrone fitting and whose metallicities are compatible with each other. fifteen of the member stars observed spectroscopically were identified together with another 19 probable members. Our results indi- cate that NGC 7193 is a genuine OCR, of a once very populous OC, for which the following parameters were derived： d = 501±46 pc, t = 2.5±1.2 Gyr, （[fe/H]） = -0.17±0.23 and E（b-V） = 0.05±0.05. Its luminosity and mass functions show depletion of low mass stars, confirming the OCR is in a dynam- ically evolved state.

关键词： open cluster remnants - Galactic open clusters

Physiological Effect of Kinetin on the Photosynthetic Apparatus and Antioxidant Enzymes Activities During Production of Anthurium

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Horticultural Plant Journal 2018年第5期4卷 182-192页

作者： de MOURA fabiana b. VIEIRA Marcos R. da S. SIMOES Adriano do N. fERREIRA-SILVA Sérgio L. de souza Carlos A.V. de souza Eduardo S. da ROCHA Alexandre T. da SILVA Luzia f. junior Miguel A. faculty of Agronomy Federal University of Pará Postgraduate Program in Plant Production Serra Talhada Academic UnitFederal Rural University of Pernambuco Department of Production Vegetable Unidade Academica de GaranhusFederal Rural University of Pernambuco

The results observed in the literature raise the hypothesis according to which cytokinin plays important roles in photosynthetic metabolisms and antioxidant enzymes. Thus, the study aimed to evaluate the effect of foliar application of the isolated cytokinin kinetin at the production cycle, seeking to analyze its effects on enzyme activity and photosynthetic parameters. The plants treated with CK presented reduction of leaf CO_2 assimilation rate(Pn) and stomatal conductance(Gs), while that transpiration rate(Tr) was unaffected. The internal CO_2 concentrations decreased with the increase in cytokinin levels, but were maintained under CK 50 mg·L^(-1). The plants treated with CK 75 mg·L^(-1) was verified higher carboxylation efficiency(Pn/Ci), which was associated to values of CO_2 assimilation and transpiration unaltered. Apparent electron transport rate showed variations in the concentration of 25 mg·L^(-1). Considering the study of enzyme activity, on the other hand, it cannot be stated that kinetin has an effective action in delaying oxidative damage. It presents mixed results, since an efficiency in the application of cytokinin was not observed, presenting induction levels of ascorbate peroxidase activity. Thus, further research is needed to determine more precisely the effects of kinetin on gas exchange and antioxidant enzymes in anthurium plants.

关键词： anthurium kinetin photosynthesis senescence plant hormone oxidative stress

The corpus cavernosum after treatment with dutasteride or finasteride： a histomorphometric study in a benign prostatic hyperplasia rodent model

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Asian Journal of Andrology 2018年第5期20卷 505-510页

作者： Marcello H A Da Silva Waldemar S Costa francisco J b Sampaio Diogo b De souza Urogenital Research Unit Rio de Janeiro State University Rio de Janeiro RJ 20551-030 Brazil

Erectile dysfunction is a common side effect of finasteride and dutasteride treatments. The objective of this study was to investigate the structural changes in the penis using a benign prostatic hyperplasia （bPH） rodent model treated with dutasteride or finasteride. Sixty male rats were divided into the following groups： C, untreated control rats; C ＋ D, control rats receiving dutasteride; C ＋ f, control rats receiving finasteride; H, untreated spontaneously hypertensive rats （SHRs）; H ＋ D, SHRs treated with dutasteride; and H ＋ f, SHRs treated with finasteride. Treatments were performed for 40 days, and penises were collected immediately thereafter. The organs were analyzed using histomorphometric methods to determine the cross-sectional penile area, as well as the surface density （Sv） of smooth muscle fibers, connective tissue, elastic system fibers, and sinusoidal spaces of the corpus cavernosum. The results were compared using a one-way ANOVA with bonferroni＇s posttest. Groups C ＋ D and C ＋ f had a significantly smaller penile cross-sectional area, but more elastic system fiber Sv compared to Group C. Group C ＋ D showed less smooth muscle Sv, and Group H showed more connective tissue but a smaller sinusoidal space Sv in the corpus cavernosum compared to Group C. Groups H ＋ D and H ＋ f had less smooth muscle Sv than Group H. Group H ＋ D also had more connective tissue and elastic system fiber Sv than Group H. both dutasteride and finasteride promoted penile modifications in the control rat penis, although this affect was ~reater in Group H animals. In this rodent model, dutasteride was the drug that most affected the corpus cavernosum.

关键词： animal models benign prostatic hyperplasia dutasteride erectile dysfunction finasteride penis

Rat cardiomyocyte H9c2(2-1)-based sulforhodamine b assay as a promising in vitro method to assess the biological component of effluent toxicity

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Journal of Environmental Sciences 2020年第10期32卷 163-170页

作者： Elsa T Rodrigues Susana f Nascimento Maria joao Moreno Paulo J Oliveira Miguel A Pardal University of Coimbra Centre for Functional EcologyDepartment of Life SciencesCalcada Martim de FreitasCoimbra 3000-456Portugal University of Coimbra Coimbra Chemistry CenterDepartment of ChemistryCoimbra 3004-535Portugal Centre for Neuroscience and Cell biology Uniuersity of CoimbraUC BiotechBiocant ParkCantanhede 3060-197Portugal

The treatment of wastewaters is crucial to maintain the ecological status of receiving waters,and thereby guarantee the protection of aquatic life and human *** quality evaluation is conventionally based on physicochemical parameters,but increasing attention has been paid to integrate physicochemical and biological ***,the regulatory use of fish in biological testing methods has been subject to various ethical and cost concerns,and in vitro cell-based assays have thus become an important topic of ***,the present study intends:(a) to evaluate the efficiency of two different sample pre-concentration techniques (lyophilisation and solid phase extraction) to assess the toxicity of municipal effluents on rat cardiomyoblast H9c2(2-1) cells,and (b) maximizing the use of the effluent sample collected,to estimate the environmental condition of the receiving *** gathered results demonstrate that the H9c2(2-1) sulforhodamine b-based assay is an appropriate in vitro method to assess biological effluent toxicity,and the best results were attained by lyophilising the sample as *** to its response,the H9c2(2-1) cell line might be a possible alternative in vitro model for fish lethal testing to assess the toxicity of municipal *** physicochemical status of the sample suggests a high potential for eutrophication,and iron exceeded the permissible level for wastewater discharge,possibly due to the addition of ferric chloride for wastewater *** general,the levels of carbamazepine and sulfamethoxazole are higher than those reported for other countries,and both surpassed the aquatic protective values for long-term exposure.

关键词： Municipal wastewater treatment plant effluent Lyophilisation Solid phase extraction Cell-based assays H9c2(2-1)cell line SRb assay

Numerical modeling of adhesion and adhesive failure during unidirectional contact between metallic surfaces

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friction 2016年第3期4卷 217-227页

作者： Eleir M.bORTOLETO Erika f.PRADOS Vanessa SERIACOPI Newton K.fUKUMASU Luiz G.D.b.da S.LIMA Izabel f.MACHADO Roberto M.souza Surface Phenomena Laboratory Department of Mechanical Engineering Polytechnic School of the University of S(a)o Paulo Av.Prof.Mello Moraes 2231 S(a)o Paulo 05508-900 Brazil federal University of AbC-UfAbC Santo André 09210-170 Brazil

In this work, we developed a finite element modeling approach to study adhesion during unidirectional contact between a two-dimensional plane-strain square and a flat slab. The surfaces were metallic or ceramic, and we analyzed different pairs of materials and their adhesion intensity using a fORTRAN subroutine (DLOAD) connected to a commercial finite element code Abaqus, which provided the surface attractive forces based on the Lennard-Jones interatomic potential using Hamaker constants. We considered adhesive loads during both the approach and separation of the surfaces. During the separation step, we modeled the material transfer between surfaces due to adhesion with respect to damage initiation and propagation at the flat slab. The parameters considered in the simulations include normal load, chemical affinity, and system size, and we analyzed different conditions by comparing the interaction forces during approach and withdrawal. This work also presents: (i) a description of the evolution of energy dissipation due to adhesion hysteresis, (ii) the formation–growth–breakage process of the adhesive junctions and the material transfer between surfaces, and (iii) an adhesive wear map based on a proposed novel equation that correlates the material parameters and material loss due to adhesion. The results indicate that the chemical affinity between bodies in contact is more related to adhesion than the applied load. In addition, the ratio between the material strength and elastic modulus seems to be an important factor in reducing adhesive wear.

关键词： adhesion adhesive failure finite element model interatomic potentials Hamaker constants

Research advances on the multiple uses of Moringa oleifera: a sustainable alternative for socially neglected population

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Asian Pacific Journal of Tropical Medicine 2017年第7期10卷 689-700页

作者： Raimunda Samia Nogueira brilhante Jamille Alencar Sales Vandbergue Santos Pereira Débora de souza Collares Maia Castelo-branco Rossana de Aguiar Cordeiro Célia Maria de souza Sampaio Manoel de Araújo Neto Paiva joao bosco feitosa dos Santos JoséJúlio CostaSidrim Marcos fábio Gadelha Rocha Department of Pathology and Legal Medicine Postgraduate Program in Medical MicrobiologySpecialized Medical Mycology CenterFederal University of Ceará School of Veterinary Medicine Postgraduate Program in Veterinary SciencesState University of Ceará Department of Social Sciences Postgraduate Program of SociologyState University of Ceará

Moringa oleifera Lam(Moringaceae) is a plant with high nutritional and medicinal value. Native to India, it is now widely distributed throughout tropical and subtropical regions of the world. Its different parts are sources of proteins, vitamins and minerals and present different pharmacological and biotechnological potential. Moreover, M. oleifera seeds are widely used in water and effluent treatment, for their coagulation, flocculation and sedimentation properties, their ability of improving water quality, by reducing organic matter and microbial load, with special applicability in intensive animal production systems, such as aquaculture. In addition, due to its high nutritional value and several medicinal properties, this tree may act as a nutritional and medical alternative for socially neglected populations. In this context, this review gathers information on M. oleifera, emphasizing its chemical constituents, nutritional, pharmacological and antimicrobial properties, applications in the treatment of water effluents, and ecological and social aspects.

关键词： Moringa oleifera biotechnology Nutrition Health Aquaculture

Persistent Xerophthalmia in a Patient with Rheumatological Disease and Priiviary Sjogren’s Syndrome: Case Report from Northern brazil

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Open Journal of Ophthalmology 2023年第2期13卷 263-266页

作者： Camile Smith de Oliveira brito Horlando junior Santos Lages Alcantara joao de joao Oliveira Leitao Limeira Julie souza da Silvat Sebastiao barreto falcao Neto joao Vlctor Oliveira de Melot Youssef Sabba Tayah David Tayah Milton Ruiz Alves federal University of Amazonas Manaus Brazil

This case study aims to contribute to the literature in order to highlight the importance of this collaboration between medical specialties. A female patient R.N.N. f, age 66, from the city of Manaus, with a previous diagnosis of Sjogren’s syndrome in regular follow-up by the Rheumatology team at the Araujo Lima outpatient clinic and referred to the Ophthalmology sector for complementary evaluation related to visual discomfort. The fundoscopy performed in the patient was within normal limits, but the symptoms experienced by her proved to be an important clinical finding, which has ratified the need for regular and multidisciplinary follow-up. This report unequivocally demonstrates that even in the face of tests considered within the expected limits for a given population, the clinical presentation can be specific and particular for each analyzed individual. Early screening exams should contemplate the patient in a holistic and individualized way whenever possible.

关键词： Sjogren’s Syndrome Ophthalmology Rheumatology Screening Disease

燃料电池式反应器中Pt和Pd中加入bi用于催化乙醇发电并选择性联产醋酸盐

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燃料化学学报 2021年第10期49卷 1540-1548页

作者： Lima f.S. fontes E.H. Nandenha J. de souza R.f.b. Neto A.O. Instituto de Pesquisas Energéticas e Nucleares IPEN/CNEN-SPCEP 05508-900 São PauloSPBrazil

直接乙醇燃料电池作为便携式移动电源受到越来越多的关注,如乙醇能量密度高、可再生、无毒、清洁、便于储存和运输等优点。然而,乙醇燃料电池的研究也面临一些严重问题,其中C−C键断裂是最为挑战的问题之一。近年来有报道表明,乙醇的完... 详细信息

直接乙醇燃料电池作为便携式移动电源受到越来越多的关注,如乙醇能量密度高、可再生、无毒、清洁、便于储存和运输等优点。然而,乙醇燃料电池的研究也面临一些严重问题,其中C−C键断裂是最为挑战的问题之一。近年来有报道表明,乙醇的完全氧化(包含C−C键断裂过程)并没有显示出燃料电池效率的增加,相反乙醇不完全氧化的催化剂会导致更明显的催化电流增加。同时金属bi掺杂会对催化剂产生电子效应和几何效应并有效增加碱性体系中催化剂的活性位中心和抗CO中毒能力。因此,本工作将铋掺杂在铂和钯中制备出Ptbi/C和Pdbi/C作为乙醇燃料电池催化剂,同时研究bi掺杂催化剂对乙醇燃料电池性能以及乙醇的不完全氧化产物醋酸盐的影响,为乙醇燃料电池电-化学品联产提供一定的依据。以硼氢化钠为还原剂,Vulcan XC-72(Cabot)导电炭为载体制备了Pt/C、Pd/C、Ptbi/C和Pdbi/C(20%质量比)炭载催化剂,其中Ptbi和Pdbi原子比均为95∶5。首先将金属前驱体溶于H_(2)O/异丙醇溶液(50/50,体积比)中,加入Vulcan XC-72导电炭黑充分混合,然后加入硼氢化钠在常温常压下充分反应,过滤洗涤干燥备用。其次,对所制备的催化剂进行TEM、XRD、XPS、电化学以及光谱电化学进行表征和测试。电化学、光谱电化学在三电极电解池中进行,将所制备的催化剂分散在超薄多孔电极上制备成工作电极,对电极为Pt片电极,参比电极为Ag/AgCl电极。电解液为碱性1 mol/L KOH的乙醇溶液,在电化学工作站上进行CV、LSV扫描以及在不同电位下测试溶液的ATR-fTIR谱。最后,燃料电池测试在一个面积为5 cm2的单电池上进行,阳极为2 mol/L乙醇+3 mol/L KOH溶液,流量为2 mL/min,阴极通入氧气,并研究催化剂的构成及性能对电池性能的影响。采用硼氢化钠还原法合成Pt/C、Ptbi(95∶5)/C、Pd/C和Pdbi(95∶5)/C。Pd/C和Pdbi/C的晶体结构呈现fCC特征,Pt/C和Ptbi/C的晶体结构也呈现fCC特征。XRD也揭示了铋原子对Pt晶体结构的影响。在1 mol/L KOH溶液中,异位XPS和循环伏安法显示这些金属具有较高的氧化态。透射电镜显示Pd/C有一定的纳米粒子聚集,Pdbi/C有一定的有序结构。红外光谱(ATR-fTIR)结果表明,bi效应由于吸附能力较弱,抑制了碳酸盐的生成,增加了醋酸盐的生成。由于醋酸盐优先生成,且不被碳酸盐离子毒害,Ptbi/C具有最佳的电化学和DEfC性能。通过在Pt和Pd掺杂金属bi制备具有电子调控的双金属炭载Ptbi(95∶5)/C和Pdbi(95∶5)/C催化剂,以增强乙醇氧化反应催化氧化过程。透射电镜(TEM)和X射线光电子能谱(XPS)结果表明,bi含量不影响Pdbi纳米颗粒的尺寸,但会影响Ptbi纳米颗粒的尺寸。X射线衍射分析表明,bi掺杂改变了Pt晶体结构中的晶格参数。此外,ATR-fTIR结果表明,碳酸盐的形成受到抑制,乙酸盐产量增加。极化曲线和功率密度曲线结果表明,Ptbi/C催化剂具有更高的功率密度,几乎是Pt/C的6倍。在线性扫描伏安实验中,Ptbi/C具有最高的电流密度(44 mW/cm2)和最低的起始电位(−0.6 V)。在电流-时间实验中,它也具有最高的最终电流密度。因此,在Pt和Pd中掺杂铋催化剂被证明是一种很有前途的燃料电池发电和醋酸盐的联产方法。

关键词：甲醇氧化反应 bi掺杂电-化学品联产

Magnetic bioassembly platforms towards the generation of extracellular vesicles from human salivary gland functional organoids for epithelial repair

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bioactive Materials 2022年第12期7卷 151-163页

作者： Ajjima Chansaenroj Christabella Adine Sawanya Charoenlappanit Sittiruk Roytrakul Ladawan Sariya Thanaphum Osathanon Sasitorn Rungarunlert Ganokon Urkasemsin Risa Chaisuparat Supansa Yodmuang Glauco R.souza joao N.ferreira Avatar biotechnologies for Oral Health and Healthy Longevity Research Unit Faculty of DentistryChulalongkorn UniversityBangkok10330Thailand faculty of Dentistry National University of Singapore119077SingaporeSingapore Department of biomedical Engineering Faculty of EngineeringNational University of Singapore119077SingaporeSingapore functional Ingredients and food Innovation Research Group National Center for Genetic Engineering and BiotechnologyNational Science and Technology Development AgencyPathum Thani12120Thailand The Monitoring and Surveillance Center for Zoonotic Diseases in Wildlife and Exotic Animals Faculty of Veterinary ScienceMahidol UniversityNakhon Pathom73170Thailand Department of Anatomy Faculty of DentistryChulalongkorn UniversityBangkok10330Thailand Department of Preclinical and Applied Animal Science Faculty of Veterinary ScienceMahidol UniversityNakhon Pathom73170Thailand Research Affairs Faculty of MedicineChulalongkorn UniversityBangkok10330Thailand University of Texas Health Sciences Center at Houston HoustonTX77030USA Nano3D biosciences Inc. HoustonTX77030USA Greiner bio-One North America Inc MonroeNC28110USA

Salivary glands(SG)are exocrine organs with secretory units commonly injured by ***-engineered organoids and extracellular vesicles(EV)are currently under investigation as potential strategies for SG ***,three-dimensional(3D)cultures of SG functional organoids(SGo)and human dental pulp stem cells(hDPSC)were generated by magnetic 3D bioassembly(M3Db)*** growth factor 10(fGf10)was used to enrich the SGo in secretory epithelial *** 11 culture days via M3Db,SGo displayed SG-specific acinar epithelial units with functional properties upon *** consistently develop 3D hDPSC in vitro,3 culture days were sufficient to maintain hDPSC undifferentiated genotype and phenotype for EV *** isolation was performed via sequential centrifugation of the conditioned media of hDPSC and SGo *** were characterized by nanoparticle tracking analysis,electron microscopy and *** were in the exosome range for hDPSC(diameter:88.03±15.60 nm)and for SGo(123.15±63.06 nm).Upon ex vivo administration,exosomes derived from SGo significantly stimulated epithelial growth(up to 60%),mitosis,epithelial progenitors and neuronal growth in injured SG;however,such biological effects were less distinctive with the ones derived from ***,these exosome biological effects were investigated by proteomic *** spectrometry profiling of SGo exosomes predicted that cellular growth,development and signaling was due to known and undocumented molecular targets downstream of *** were identified as one of the novel targets requiring further ***,M3Db platforms can generate exosomes with potential to ameliorate SG epithelial damage.

关键词： Salivary gland Hyposalivation Human dental pulp stem cells Magnetic bioassembly Organoids Exosome