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Preparation of High Purity Neodymium Oxide from Brazilian Monazite by Ion Exchange

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Journal of Energy and Power Engineering 2015年第7期9卷 616-621页

作者： Carlos Alberto da Silva Queiroz Jose Antonio Seneda Walter dos reis Pedreira Filho IPEN/CNEN-SP (Instituto de Pesquisas Energeticas e Nucleares/Comissao Nacional de Eneergia Nuclear-Sao paulo) Cidade Universitaria Sao Paulo 05508-000. Brazil Fundacao Jorge Duprat Figueiredo de Seguranca e Medicina do Trabalho-FUNDACENTRO Sao Paulo 05409-002 Brazil

A simple and economical chemical process for obtaining high purity neodymium oxide is discussed. The raw material in the form of RE （rare earth） carbonates is produced industrially in Brazil from monazite. Using this concentrate as the feed material, ion exchange with a strong cationic resin, commonly used for water treatment, and without the use of retention ions was used for the fractionating of the REE （rare earth elements）. The eluent was ammonium salt of EDTA （ethylenediaminetetraacetic acid） at pH 4.0. The complex of EDTA-neodymium was transformed into neodymium oxides via oxalate precipitation. We produced 99.9% pure Nd203 in yields greater than or equal to 80%. Molecular absorption spectrophotometry was used to monitor the neodymium content during the process and sector field inductively coupled plasma mass spectrometry was used to certify the purity of the neodymium oxides. The typical neodymium oxides obtained contained the followings contaminants in micrograms per gram： Sc （4.09）; Y （0.39）; La （0.78）; Ce （5.62）; Pr （4.56）; Sm （11.10）; Eu （1.10）; Gd （14.30）; Tb （29.3）; Dy （4.15）; Ho （8.39）; Er （13.80）; Tm （0.23）; Yb （2.29）; Lu （0.39）. High purity neodymium oxides obtained from this procedure replaced the imported product used in research and development work on rare earth at IPEN/CNEN-SP （Instituto de Pesquisas Energeticas e Nucleares/Comissfio Nacional de Eneergia Nuclear-Sao paulo）.

关键词： Neodymium oxide elemental rare earths separation rare earths.

No independent associations between physical activity and clinical outcomes among hospitalized patients with moderate to severe COVID-19

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Journal of Sport and Health Science 2021年第6期10卷 690-696页

作者： Ana J.Pinto Karla F.Goessler Alan L.Fernandes Igor H.Murai Lucas P.Sales Bruna Z.reis Mayara Diniz Santos Hamilton Roschel Rosa M.R.Pereira Bruno Gualano Applied Physiology and Nutrition Research Group School of Physical Education and SportClinical Hospital HCFMUSPSchool of Medicine FMUSPUniversity of Sao PauloSao PauloSP 01246903Brazil Rheumatology Division Clinical Hospital HCFMUSPSchool of Medicine FMUSPUniversity of Sao PauloSao PauloSP 01246903Brazil Food Research Center University of Sao PauloSao PauloSP 05508080Brazil

Background:Regular physical activity(PA)has been postulated to improve,or at least maintain,immunity across the life ***,the link between physical(in)activity and coronavirus disease 2019(COVID-19)remains to be *** small-scale prospective cohort study is nested within a randomized controlled trial aimed to investigate the possible associations between PA levels and clinical outcomes among hospitalized patients with moderate to severe ***:Hospitalized patients with COVID-19(mean age:54.9 years)were recruited from the Clinical Hospital of the School of Medicine of the University of Sao paulo(a quaternary referral teaching hospital)and from Ibirapuera Field Hospital,both located in Sao paulo,*** level was assessed using the Baecke Questionnaire of Habitual Physical *** primary outcome was hospital length of *** secondary outcomes were mortality,admission to the intensive care unit(ICU),and mechanical ventilation ***:The median hospital length of stay was 7.0§4.0 days,median§IQR;3.3%of patients died,13.8%were admitted to the ICU,and 8.6%required mechanical *** linear regression models showed that PA indices were not associated with hospital length of stay(work index:b=-0.57(95%confidence interval(95%CI):-1.80 to 0.65),p=0.355;sport index:b=0.43(95%CI:-0.94 to 1.80),p=0.536;leisure-time index:b=1.18(95%CI:-0.22 to 2.59),p=0.099;and total activity index:b=0.20(95%CI:-0.48 to 0.87),p=0.563).None of the PA indices were associated with mortality,admission to the ICU,or mechanical ventilation requirement(all p>0.050).Conclusion:Among hospitalized patients with COVID-19,PA did not independently associate with hospital length of stay or any other clinically relevant *** findings should be interpreted as meaning that,among already hospitalized patients with more severe forms of COVID-19,being active is a potential protective factor likely outweighed by a cluster of comorbidities(e.

关键词： Hospital length of stay Lifestyle Physical inactivity Prognosis SARS-CoV-2

Promoter hypermethylation of CDH1, FHIT, MTAP and PLAGL1 in gastric adenocarcinoma in individuals from Northern Brazil

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World Journal of Gastroenterology 2007年第18期13卷 2568-2574页

作者： Mariana Ferreira Leal Eleonidas Moura Lima Patrícia Natália Oliveira Silva paulo Pimentel Assumpo Danielle Queiroz Calcagno Spencer Luiz Marques Payo Rommel Rodríguez Burbano Marília de Arruda Cardoso Smith Genetics Division Department of Morphology Federal University of So Paulo So Paulo SP Brazil Department of Biology Campus Ministro Reis Velloso/Parnába Federal University of Piauí PI Brazil Joo de Barros Barreto University Hospital Federal University of Pará Belém PA Brazil Human Cytogenetics and Toxicological Genetics Laboratory Department of Biology Center of Biological Sciences Federal University of Pará Belém PA Brazil Genetics and Molecular Biology Hemocenter Faculty of Medicine of Marília Marília SP Brazil

AIM：To evaluate the methylation status of CDH1, FHIT, MTAP and PLAGL1 promoters and the association of these findings with clinico-pathological characteristics.METHODS： Methylation-specific PCR （MSP） assay was performed in 13 nonneoplastic gastric adenocarcinorna, 30 intestinal-type gastric adenocarcinorna and 35 diffuse-type gastric adenocarcinorna samples from individuals in Northern Brazil. Statistical analyses were performed using the chi-square or Fisher＇s exact test to assess associations between rnethylation status and clinico-pathological characteristics.RESULTS： Hypermethylation frequencies of CDH1, FHIT, MTAPand PLAGL1 promoter were 98.7%, 53.9%, 23.1% and 29.5%, respectively. Hyperrnethylation of three or four genes revealed a significant association with diffuse-type gastric cancer compared with nonneoplastic cancer. A higher hyperrnethylation frequency was significantly associated with H pylori infection in gastric cancers, especially with diffuse-type. Cancer samples without lymph node metastasis showed a higher FHIT hypermethylation frequency. MTAP hypermethylation was associated with H pylori in gastric cancer samples, as well as with diffuse-type compared with intestinal-type. In diffuse-type, MTAP hypermethylation was associated with female gender.CONCLUSION： Our findings show differential gene methylation in tumoral tissue, which allows us to conclude that hypermethylation is associated with gastric carcinogenesis. MTAP promoter hypermethylation can be characterized as a marker of diffuse-type gastric cancer, especially in women and may help in diagnosis, prognosis and therapies. The H pylori infectious agent was present in 44.9% of the samples. This infection may be correlated with the carcinogenic process through the gene promoter hypermethylation, especially the MTAP promoter in diffuse-type. A higher H pylori infection in diffuse-type may be due to greater genetic predisposition.

关键词： Gastric adenocarcinoma DNA hypermethylation CDH1 FHIT MTAP PLAGL1

Bond Behavior between Recycled Concrete Containing CDW and Different Types of Steel Bars

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Journal of Architectural Environment & Structural Engineering Research 2021年第2期4卷 1-7页

作者： Carine N.S.reis paulo Lima Mônica B.Leite Department of Technology Post-graduation Program of Civil and Environmental EngineeringState University of Feira de SantanaBahiaBrazil

The operation of reinforced concrete structures is directly associated with the adhesion between the steel bar and the concrete,which allows the internal forces to be transferred to the reinforcement during the process of loading the structural *** modification of the concrete composition,with the introduction of recycled aggregate from construction and demolition waste(CDW),affects the steel-concrete interface and can modify the bonding stress,which is also influenced by the type and diameter of the bar *** this work,the influence of the recycled fine aggregate(RFA)and types of steel bar on the steel-concrete bond was experimentally evaluated using the pullout *** concrete and recycled concrete,with RFA replacement level of 25%,were *** types of steel rebars(i.e.,plain and deformed)with diameters of 10.0 and 16.0 mm were considered in this *** results indicate a reduction in the adhesion stress with the introduction of recycled aggregate,but this trend is influenced by the diameter of the bar *** use of ribbed bars modifies the stress bon-slip behavior,with an increase in the average bond strength,which is also observed with the reduction of the diameter of the bar.

关键词： Construction and demolition waste(CDW) Recycled concrete Steel-concrete bond behavior

Chilled Semen of Captive Collared Peccaries （Pecari tajacu）： Effects of Preservation at 17 ℃ on Semen Quality

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Journal of Agricultural Science and Technology(A) 2012年第7期2卷 921-929页

作者： Alexandre Rossetto Garcia Priscila reis Kahwage Diva Anelie de Aratljo Guimaraes Otavio Mitio Ohashi Brazilian Agricultural Research Corporation/Embrapa Southeast Livestock-Rod Washigton Luiz km 234 Sao Carlos Sao Paulo 13560-970 Brazil Federal University of Parci Rua Augusto Correa n. 1 Belem Parcl 66075-110 Brazil

The trade creation and conservation of wild species in Amazon, including collared peccaries （Pecari tajacu）, may be favored by artificial insemination, but the time of semen storage may lead to reduced fertility in sperm of some wild animals. Thus, the aim of this research was to evaluate the influence of semen storage at 17 ℃ over time on seminal features of peccaries in captivity. Eight adult males were sedated and underwent electroejaculation. The ejaculates （n = 65） were evaluated for volume, concentration, pH, sperm motility, vigor, and cell with intact plasma membrane intact （IPM） and sperm morphology. Selected ejaculates （n = 21） were diluted （1：1） in Beltsville Thawing Solution and kept during 48 hours under controlled temperature （17 ℃）. Assessments were made after dilution （TO）, after 24 hours （T24）, and 48 hours after the onset of cooling （T48）. The storage impacted on sperm survival （P 〈 0.05）. Semen characteristics changed throughout the storage period studied and after 48 hours storage. The decline of sperm motility was of 55.2% for 10.9%, vigor was 2.3 for 0.5 and IPM cells were of 59.0% for 15.8%. Primary defects sperm increased of 19.8% for 32.2%, secondary defects of 9.8% for 10.4% and total defects of 29.4% for 42.7%. However, within 24 hours of preservation, chilled semen peccaries presented sperm motility average rate and IMP cells levels indicative to use in assisted reproductive events. These results indicate chilled semen for 24 hours could be used in experimentally artificial insemination of peccaries, technology that still has not been performed before.

关键词： Sperm collared peccary wildlife semen conservation Amazon.

Tomatoes Maturation Analysis with Reflectance Spectral Images

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Journal of Agricultural Science and Technology(B) 2017年第6期7卷 426-431页

作者： Julia Lopes Governici Rodrigo Magalhaes Faria Rodolpho Cesar dos reis Tinini Barbara Janet Teruel Mederos Department of Agricultural Engineering Federal University of Vifosa Vifosa Minas Gerais 36570-000 Brazil Department of Plant Science Federal University of Vigosa Vicosa Minas Gerais 36570-000 Brazil Agricultural Sciences Institute Federal University of Minas Gerais Montes Claros Minas Gerais 39404-547 Brazil College of Agricultural Engineering The State University of Campinas Campinas Sao Paulo 13083-875 Brazil

The demands for high quality products are increasing in the market, so several tests are performed. These analyses are destructive, time consuming and sometimes expensive. The spectral imaging technique is an alternative that can reduce costs and time and increase the efficiency and cost-effectiveness of these analyses. In this context, the aim of this study was to verify the spectral behavior of the tomato in function of the maturation and its potential use for non-destructive evaluation of food quality. Eighty tomatoes of the Italian group were selected in four stages of maturation （green, pink, light red and red）. Images were collected in wavelengths 480 nm to 710 nm （every 10 nm）. After the images were collected, the fruits were submitted to the physical-chemical analyses. The following parameters were analyzed： color, color index （CI）, pH, soluble solids （SS）, total titratable acidity （TTA） and ratio （SS/TTA）. After characterization the mean spectrum was obtained by the extraction of the spectral characteristics. It was observed that the spectral behavior was the same for all stages of maturation. It was possible to differentiate the green tomatoes in the wavelengths from 520 nm to 560 nm and from 610 nm to 660 nm. These intervals represent the area of reflection of chlorophyll and lycopene, respectively. Near the wavelength 560 nm, the highest absorbance was recorded by ripe tomatoes due to the concentration of lycopene. It is concluded that the best wavelengths for analysis are those in which green has the highest reflectance and it is possible to apply this technique for non-destructive analysis of the maturation of tomatoes.

关键词： Non-destructive analysis mean spectrum physical-chemical analysis Solanum lycopersicum

GIS as a Decision Support Tool in the Area of Influence of the Nuclear Complex Angra dos reis, Brazil

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Journal of Geographic Information System 2013年第1期5卷 13-23页

作者： Corbiniano Silva Luiz Landau Luiz Claudio Gomes Pimentel paulo Fernando Lavalle Heilbron Filho Civil Engineering Program Alberto Luiz Coimbra Institute of Post Graduate Studies and Research Federal University of Rio de Janeiro Rio de Janeiro Brazil Mechanical Engineering Program Alberto Luiz Coimbra Institute of Post Graduate Studies and Research Federal University of Rio de Janeiro Rio de Janeiro Brazil National Commission for Nuclear Energy Rio de Janeiro Brazil

The outlook concerning the occurrence of industrial accidents has led to the implementation of response systems based on geoprocessing tools, which are widely adopted in emergency for such ventures, since they have helped and served as a support for decision making, as well as for the preparation of guidelines aimed at managing emergencies. Nuclear power plants, because they constitute types of industrial activities that present dangerous conditions and attention regarding security are characterized as hazardous, especially due to consequences that occurred from large accidents— such as Chernobyl (1986) and Fukushima (2011)—highlighting the importance to its negative impacts, since the occurrence of accidents at nuclear power plants may affect surrounding areas, thus exposing a set of elements that are part of the environmental dynamics that integrates the catchment area where this type of plant is situated. In this way, through an integrated view of the region where the nuclear complex is located in Angra dos reis City (Rio de Janeiro State) and, also, by aggregating information that portray the geobiophysical reality of its surroundings, several elements were incorporated into a database developed in a virtual environment, in which was produced a geographic information system (GIS) that presents a complex of variables that, once considered, can enhance various analysis in order to support emergency situations and planning, as well as guidelines that help define actions from the occurrence of accidental events at the nuclear plant.

关键词： Industrial Accidents Nuclear Power GIS Planning of Emergency Response Systems

Drainage Bed:A Natural System for WTP Sludge Dewatering and Drying with Different Coagulant Chemicals in Tropical Countries

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Journal of Water Resource and Protection 2014年第11期6卷 1029-1036页

作者： Marcelo M.Barroso Cali L.Achon Renan F.reis Joao S.Cordeiro ISITEC—Higher Institute of Innovation and Technology Sao PauloBrazil EESC/USP—University of Sao paulo at Sao Carlos School of Engineering Sao CarlosBrazil UFSCar—Federal University of Sao Carlos Sao CarlosBrazil UFSCar—Federal University of Sao Carlos Sao CarlosBrazil

This study seeks to evaluate the mechanisms for dewatering sludge from Water Treatment Plants (WTP) in a natural system that uses nonwoven polyester geotextile blankets named Drainage Bed (DB). Dewatering mechanisms are divided into two stages: Drainage and Drying Phases. For the Drainage Phase, the results showed that the solids content of the Aluminum Sulfate sludge reached 8.9% to 18.3% and the PACl sludge 1.8% to 6.5%, the volume reduction on this phase exceeding 50% and 74%, respectively. The final solids content, after the Drying Phase, was greater than 28%, reaching 90%. In the Drainage Phase the lower the Surface Application Rate—SAR [kg/m2] is, the greater the drainage flow will be. In the Drying Phase, moisture and insolation were key factors in drying sludge. Thus, the Drying Phase in the DB takes special attention for being virtually nonexistent in dewatering technologies in a closed system (confined) without exposure to solar energy. The use of the DB as a natural system for dewatering WTP sludge in tropical countries proved to be a promising alternative, because of its efficient removal of water from sludge coupled with operational simplicity and low costs, provided there is area available.

关键词： Sludge Dewatering Drying Drainage Bed(DB) Geotextile Blanket

Passivation of the Zinc Anode of a Crude Oil Vertical Separator Resulting in Corrosion

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材料科学与工程（中英文B版） 2016年第2期6卷 63-67页

作者： Femando Benedlcto Mamler Juan Manuel Pardal Pedro paulo Barbosa Leite Marcone Freitas dos reis Engineering School Federal Fluminense University (UFF) Niteroi Rio de Janeiro 24220-261 Brazil