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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

Integrated risk management: a Petrobras application in offshore well construction safety to minimize critical emergency disconnections

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Petroleum Science 2018年第2期15卷 421-431页

作者： Claudio Benevenuto de Campos Lima Pedro Esteves Aranha jose Francisco Tebaldi de Castro Gilson Brito Alves Lima Augusto Borella Hougaz Felipe de souza Terra Petrobras department of Production Engineering Federal Fluminense University

In order to avoid mistakes and to save a great deal of time in analysis, an innovative methodology was developed that can analyze the well operations and rig characteristics involved to define the best emergency disconnect sequence （EDS） available. A solution was developed based on the characteristics of the rigs and blowout preventers （BOPs）, and six variables were considered that directly affect the choice of EDS. All possible combinations of 64 scenarios were analyzed, and the priority of choice of the EDS was defined empirically. This paper presents an approach to EDS risk management and examples of exposure time （time without riser safety margin and shear capability） for the same well, which can be lowered from 13% to 0.1%. The impact of this reduction is related to the ability of the BOP to cut some of the heavy casings, in addition to improved availability of EDS modes. This implementation opened up many possibilities for the performance of risk exposure analysis, enabling comparison of several BOP configurations of contracted rigs and selection of the best options. This innovative approach allowed a better management of the rig schedules, prioritizing safety aspects and making it possible to allocate the fleet in a systematic way.

关键词： Well safety Safety barriers Emergency disconnect sequence (EDS) Well control Kick Well design

CFD predictions for hazardous area classification

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Chinese Journal of Chemical Engineering 2019年第1期27卷 21-31页

作者： Andrey Oliveira de souza Aurélio Moreira Luiz Ant?nio Tavernard Pereira Neto Ant?nio Carlos Brandao de Araujo Heleno Bispo da Silva Sidinei Kebler da Silva jose Jailson Nicacio Alves Federal Institute of Education Science and Technology of Paraiba Petrobras-Petróleo Brasileiro S.A. Federal University of Campina Grande

This study aimed to describe a Computational Fluid Dynamics(CFD) procedure using the ANSYS CFX software 16.1 and design of Experiments for the determination of volume and extension of explosive atmospheres due to fugitive emissions of flammable *** multidimensional statistical sampling technique Latin Hypercube was used, which defined 100 simulations of random methane gas leak *** CFD model proved to be robust in predicting the extension and volume of the explosive atmosphere for orifice diameters from 0.1 to2.5 mm, pressure from 0.1 MPa to 12 MPa and temperatures from 0 ℃ to 400 ℃.It was found that the calculation domain must be parameterized 8 m in length for each millimeter of the diameter of the source of release to ensure the *** order not to lose precision for very small diameters, the mesh was parameterized with 50 elements along the orifice *** was proved that gravity does not influence the extension and volume of the explosive atmosphere at sonic *** deviation from the ideal gas behavior in the reservoir,achieved by applying the Soave–Redlich–Kwong equation of state, also has not significantly influenced the extension and volume of the explosive *** results showed that the size of the explosive atmosphere varies directly with the diameter of the source emission and reservoir pressure, and inversely with the temperature of the *** diameter of the source is the parameter that has the major effect on the extension of the explosive atmosphere, followed by the pressure and lastly the temperature of the reservoir.

关键词： Computational Fluid Dynamics Computer simulation Safety Fugitive emissions Classified area Flammable gas cloud

Clinical and environmental isolates of Burkholderia pseudomallei from Brazil: Genotyping and detection of virulence gene

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Asian Pacific Journal of Tropical Medicine 2017年第10期10卷 945-951页

作者： Tereza de Jesus Pinheiro Gomes Bandeira debora de souza Collares Maia Castelo-Branco Marcos Fabio Gadelha Rocha Rossana de Aguiar Cordeiro Crister jose Ocadaque Manoel de Araújo Neto Paiva Raimunda Samia Nogueira Brilhante jose Júlio Costa Sidrim Specialized Medical Mycology Center Postgraduate Program in Medical Microbiology Federal University of Ceará Christus School of Medicine Postgraduate Program in Veterinary Sciences State University of Ceará Federal Institute of Education Science and Technology of Ceará

Objective: To evaluate the genetic diversity of clinical and environmental isolates of Burkholderia pseudomallei(***) recovered in Ceara, Brazil, and screen these isolates for the presence of type three secretion system virulence ***: Nineteen *** isolates(9 from clinical cases and 10 from soils)were *** amplified polymorphic DNA was performed with primers OPQ-2, OPQ-4 and OPQ-16 to evaluate the genetic diversity, and type three secretion system gene was detected through polymerase chain ***: Random amplified polymorphic DNA showed a genetic relatedness of approximately 50% among the tested *** isolates, which were grouped into two clades, of which the biggest ones comprised 18/19 isolates for primer OPQ-2, and 17/19 isolates for primer *** OPQ-4 grouped the isolates into three clades comprising 1/19, 3/19 and 15/19 ***, type three secretion system gene was detected in all tested ***: This is an effort to type *** strains from Ceara, which is important for better understanding this pathogen, contributing for the epidemiological surveillance of melioidosis in this endemic region.

关键词： Burkholderia pseudomallei Melioidosis RAPD TTSS gene

177Hf as a Competitor in the Synthesis of 177Lu-DOTAtate

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Journal of Chemistry and Chemical Engineering 2016年第5期10卷 238-240页

作者： jose de souza Caldeira Filho Centro de Tecnologia das Radiacoes. Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN/SP. Av.

This study reveals the interference of 177Hf, a decay product of 177Lu, in the synthesis of 177Lu-DOTAtate, In the experiments we followed three 177Lu t1/2. The molar ratio Lu： DOTAtate used was calculated for each decay, in two situations： 1） without considering the influence of 177Hf; 2） considering the influence of 177Hf. The results compare both the calculated molar ratio and the radionuclide incorporation yields （%） in these situations. The yields increase when 177Hf influence is considered. This suggests that 177Hf is an important competitor for DOTAtate binding site. These data are relevant in the synthesis of the radiopharmaceutical 177Lu-DOTAtate with high specific activity.

关键词： Hafnium 177Lu-DOTAtate molar ratio radiopharmaceutical.

Vibrio *** Macrobrachium amazonicum prawn farming are inhibited by Moringa oleifera extracts

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Asian Pacific Journal of Tropical Medicine 2015年第11期8卷 899-902页

作者： Raimunda Samia Nogueira Brilhante Jamille Alencar Sales Celia Maria de souza Sampaio Francisco Geraldo Barbosa Manoel de Araujo Neto Paiva Glaucia Morgana de Melo Guedes Lucas Pereira de Alencar Yago Brito de Ponte Tereza de Jesus Pinheiro Gomes Bandeira jose Luciano Bezerra Moreira debora de souza Collares Maia Castelo-Branco Waldemiro de Aquino Pereira-Neto Rossana de Aguiar Cordeiro jose Julio Costa Sidrim Marcos Fabio Gadelha Rocha department of Pathology and Legal Medicine Postgraduate Program in Medical MicrobiologySpecialized Medical Mycology CenterFederal University of Ceara School of Veterinary Medicine Postgraduate Program in Veterinary SciencesState University of Ceara department of Organic and Inorganic Chemistry Federal University of Ceara

Objective:To investigate the in vitro antimicrobial potential of extracts of stem,leaves,flowers,pods and seeds of Moringu okifera(***) against Vibrio *** hatchery water and the prawn Mmrobrachium ***:The ethanol extracts of stem,leaves,pods and seeds and chloroform extract of flowers of *** were tested against Vibrio cholerue(***) serogroups non-O1/non-O139(n=4).Vibrio vulnificus(n=l) and Vibrio mimicus(n=1).Escherichia coli(***)(ATCC(?) 25922) was used as quality *** species were obtained from Macmbrachium amazonicum prawns and from hatchery water from prawn *** Minimum Inhibitory Concentration(MIC) was determined by broth microdilution ***:The best result was obtained with the ethanol extract of pods,which inhibited three strains of the ***,Vibrio vulnificus,Vibrio minimis and ***(MIC range 0.312-5.000 mg/mL).The chloroform extract of flowers was effective against all *** strains and ***(MIC range 0.625-1.250 mg/mL).However,the ethanol extracts of stem and seeds showed low effectiveness in inhibiting the bacterial ***:The extracts of pods,flowers and leaves of *** have potential for the control of Vibrio *** studies are necessary to isolate the bioaetive compounds responsible for this antimicrobial activity.

关键词： Prawn Macrobrachium amazonicum Moringa oleifera Vi

Chemical composition of Rosmarinus officinalis essential oil and antioxidant action against gastric damage induced by absolute ethanol in the rat

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Asian Pacific Journal of Tropical Biomedicine 2016年第8期6卷 677-681页

作者： Christiane Takayama Felipe Meira de-Faria Ana Cristina Alves de Almeida Ricardo jose Dunder Luis Paulo Manzo Eduardo Augusto Rabelo Socca Leonia Maria Batista Marcos jose Salvador Alba Regina Monteiro souza-Brito Anderson Luiz-Ferreira Functional and Structural Biology department Biology Institute Campinas State University Pharmacology department Faculty of Medical Sciences Campinas State University department of Pharmaceutical Sciences Federal University of Paraiba Plant Physiology department Biology Institute Campinas State University Federal University of Goias Institute of Biotechnology Nucleus of Biological Sciences Regional Catalao

Objective: To evaluate the antioxidant activity of the essential oil obtained from Rosmarinus officinalis(R. officinalis) in ethanol-induced gastric ulcer model in ***: The antioxidant properties of the essential oil obtained from R. officinalis were evaluated against gastric injury induced by absolute ethanol. Gastric tissues were prepared to enzymatic assays. The levels of glutathione, lipid peroxides, and the activities of glutathione peroxidase, superoxide dismutase and myeloperoxidase were ***: Ethanol produced severe hemorrhagic lesions in the stomach with ulcerative lesion of(140.2 ± 37.2) mm2. In animals pretreated with essential oil of R. officinalis(50 mg/kg, p.o.), a significant inhibition of mucosal injury of(21.2 ± 7.1) mm2(84%inhibition) was observed. The essential oil of R. officinalis protected the gastric mucosa probably by modulating the activities of the enzymes(superoxide dismutase and glutathione peroxidase) and increasing or maintaining the levels of glutathione. In addition,lipid peroxides levels were reduced. The essential oil of R. officinalis was analyzed by gas chromatography–mass spectrometer and the main constituents were cineole(28.5%),camphor(27.7%) and alpha-pinene(21.3%).Conclusions: We suggest that the monoterpenes present in the essential oil obtained from R. officinalis may be among the active principles responsible for the antioxidant activity shown by essential oil of R. officinalis.

关键词： Rosmarinus officinalis L. Antioxidant activity Gastric ulcer Antioxidant enzymes

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 Pdensity,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

Ecophysiological acclimatization to cyclic water stress in Eucalyptus

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Journal of Forestry Research 2020年第3期31卷 797-806页

作者： Rogerio de souza Noia Junior Genilda Canuto Amaral jose Eduardo Macedo Pezzopane Mariana Duarte Silva Fonseca Ana Paula Camara da Silva Talita Miranda Teixeira Xavier department of Biosystems Engineering ESALQ University of Sao PauloPiracicabaSao PauloBrazil department of Forestry Sciences NEDTEC Federal University of Espirito SantoJero nimo MonteiroEspirito SantoBrazil

Drought is considered the main environmental factor limiting productivity in eucalyptus plantations in Brazil. However, recent studies have reported that exposure to water deficit conditions enables plants to respond to subsequent stresses. Thus, this study investigates the ecophysiological acclimatization of eucalyptus clones submitted to recurrent water deficit cycles. Eucalyptus seedlings were submitted to three recurrent water deficit cycles and anatomical, morphological and physiological changes were analyzed. The results were:(1) Eucalyptus seedlings responded to water deficits by directing carbohydrates to root and stem growth;(2) Size and number of stomata were reduced;(3) Stomatal conductance decreased which allowed the plants to reduce water losses through transpiration,increasing instantaneous water use efficiency;(4) The relationship between gas exchanges and available water contents allowed the seedlings to uptake the retained soil water athigher tensions;and,(5) Physiological recovery from subsequent water deficits became faster. As a result of these changes, the eucalyptus seedlings recovered from the same degree of water stress more rapidly.

关键词： Carbon partition Drought Gas exchange Morpho-physiological changes Photosynthetic apparatus