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Simultaneous Measurements of Rainfall Intensity, Low Energy Neutrons and Gamma Radiation in Sao Jose Dos Campos, SP, Brazil 被引量:1
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作者 Marcelo Pego Gomes Inacio Malmonge Martin +4 位作者 Mauro Angelo Alves Bogos Nubar Sismanoglu Marco Antonio S. Ferro Marcos Pinto Flavio Antonio 《Journal of Environmental Science and Engineering(B)》 2013年第11期643-647,共5页
The article aims to study the possible correlation between the presence and intensity of rainfall X- and T-radiation and low energy neutrons at one specific location in S[io Jos6 dos Campos, SP, Brazil. Monitoring of ... The article aims to study the possible correlation between the presence and intensity of rainfall X- and T-radiation and low energy neutrons at one specific location in S[io Jos6 dos Campos, SP, Brazil. Monitoring of these parameters was carried out from end February to half of June 2013 just in Physics Department of ITA (Technological Institute of Aeronautics). By correlating the data of measurements of intensity of X and ),-radiations with the rainfall it has been found that this meteorological parameter had a significant influence on the background of these radiation profile. A possible reason for this fact is associated with the presence of radon gas in the environment that is dragged to the surface during the occurrences of local rainfall. In relation neutrons, it was possible to note that the rainfall has small influence on this parameter measures. 展开更多
关键词 X- and y-radiation low energy neutron rainfalls experimental measurements.
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Monitoring of Ionizing Radiation and Rain Intensity during May to October 2015 in S^o Jos~ dos Campos, Brazil
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作者 Inacio Malmonge Martin Thiago Adriano dos Santos +2 位作者 Franklin Andrade da Silva Marcelo Pego Gomes Bogos Nubar Sismanoglu 《Journal of Environmental Science and Engineering(B)》 2016年第3期115-117,共3页
Radiation affects the environment and local human activity in any location of the earth's surface. Due to this fact, the aim of this study was to monitor the ionizing radiation and rain intensity using portable devic... Radiation affects the environment and local human activity in any location of the earth's surface. Due to this fact, the aim of this study was to monitor the ionizing radiation and rain intensity using portable devices. During May 23 to October 2, 2015, it was made measures the intensity of gamma radiation from 30 keV to 10.0 MeV at a height of 25 meters in Sao Jos6 dos Campos city, SP, Brazil. It was used a crystal of sodium iodide scintillator 3 - 3 inches coupled to a photomultiplier and associated electronic. The measurements were made continually with minute's interval throughout the period and it was monitored rain intensity every minute at the same height of the tower. In this job, it was possible to correlate rain-radiation and it was observed which gamma radiation has a directly proportional relationship with rain and visible frequency of 1 day. 展开更多
关键词 Gamma radiation rain intensity radon gas gamma scintillator.
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Monitoring of Ionizing Radiation from Radon Gas (Rn-222) in Sao Jose Dos Campos--Brazil Region
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作者 Inacio Malmonge Martin Franklin Andrade da Silva Marcelo Pego Gomes 《Journal of Environmental Science and Engineering(B)》 2013年第8期449-452,共4页
It is common knowledge that we live in an environment which comprises ionizing radiation (X-rays, gamma rays). These radiation in normal situations is produced by natural phenomena such as cosmic rays from different... It is common knowledge that we live in an environment which comprises ionizing radiation (X-rays, gamma rays). These radiation in normal situations is produced by natural phenomena such as cosmic rays from different sources in Universe and the decay of radioactive elements present in the Earth planet atmosphere and crust. Ionizing radiation can also be produced by human activities such as those related to nuclear power generation and use in medicine and industry. Although ionizing radiations are part of our daily lives, few students or researchers have the opportunity to perform measurements and observations of the background radiation. To overcome this deficiency in education, we started a pilot project that propose measures and observations of environmental radiation background with students of the ITA (Technological Institute of Aeronautics, Silo Paulo). Using compact and portable detector to observe gamma radiation like described in this work, many graduate students can participate. 展开更多
关键词 ATMOSPHERE radon gas gamma radiation.
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Dynamics of Environmental Ionizing Radiation between May to September 2016 in the Region of S^o Jos~ dos Campos, SP, Brazil
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作者 Inacio M. Martin Marcelo P. Gomes +5 位作者 Mauro A. Alves Alessandro de Abreu Franklin A. Silva Rodrigo R. F.Carvalho Joao P. Correa Bogos N. Sismanoglu 《Journal of Environmental Science and Engineering(B)》 2016年第9期451-456,共6页
Measurements of gamma radiation (200 keV to 10 MeV) were performed between May 25 to September 30 2016 at ITA (Technological Institute of Aeronautics) in Sao Jose dos Campos, SP, Brazil. Detector and associated el... Measurements of gamma radiation (200 keV to 10 MeV) were performed between May 25 to September 30 2016 at ITA (Technological Institute of Aeronautics) in Sao Jose dos Campos, SP, Brazil. Detector and associated electronics were previously calibrated in the laboratory of ITA using radioactive sources Cs-137, Po-210 and Sr-90. These sources provide gamma-ray energies in 0.662 keV alpha particles of 5.4 MeV and 0.90 keV electrons, respectively. Detector is a scintillator Sodium Iodide activated with Thallium [NaI(Tl)] associated to a photomultiplier and electronic devices which gather, store, distribute and structure data so users can analyze them. During the period of May-September, the experimental set was installed in an open room on a tower 25 meters above the ground. Measurements indicated variations of ionizing radiation in function of dry weather, rain, cold fronts passes and presence of fog in the area; the sample time interval was minute by minute. This study discusses the analysis and the dynamics of how to measure meteorological parameters using an ionizing radiation system. 展开更多
关键词 Ionizing radiation environmental study gamma radiation measurements.
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Monitoring of Ionizing Radiation Using Geiger Instrument during February to April 2015 in Sao Jose Dos Campos, SP, Brazil
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作者 Inacio Malmonge Martin Marcelo Pego Gomes +2 位作者 Bogos Nubar Sismanoglu Thiago Adriano Dos Santos Joao Paulo Correa 《Journal of Environmental Science and Engineering(A)》 2015年第6期282-285,共4页
Measures of ionizing radiation were observed in a tower which is 20 meters above the ground relative height. They show a distinct period of 24 hours oscillation during this Februaryl 1 to April 11, 2015. It is suggest... Measures of ionizing radiation were observed in a tower which is 20 meters above the ground relative height. They show a distinct period of 24 hours oscillation during this Februaryl 1 to April 11, 2015. It is suggested that these oscillations originate from radon gas (222Rn) vented from the ground floor. One Russian specific Geiger tube with associated electronics developed at ITA was used, Monitoring of ionizing radiation from 30 keV to l0 MeV shows that the X and gamma rays up to 3.0 MeV is prevalent in the region comes from the Radon gas 222Rn that decay in 214Bi and 214pb in the energies of the gamma rays 0.269, 0.609 and 1.05 MeV respectively. Then, with this simple, portable instrument was possible to monitoring the dynamics of radon gas in the region every interval minutes. 展开更多
关键词 Atmosphere radon gas gamma radiation.
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Endoscopic sleeve gastroplasty in class Ⅲ obesity:Efficacy, safety, and durability outcomes in 404 consecutive patients 被引量:4
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作者 Daniel Barry Maselli Anna Carolina Hoff +13 位作者 Ashley Kucera Emily Weaver Laura Sebring Lori Gooch Kathleen Walton Daniel Lee Taylor Cratty Selena Beal Srikar Nanduri Kendall Rease Christina S Gainey Laura Eaton Brian Coan Christopher E McGowan 《World Journal of Gastrointestinal Endoscopy》 2023年第6期469-479,共11页
BACKGROUND Endoscopic sleeve gastroplasty(ESG) is an effective therapy for class Ⅰ-Ⅱ obesity, but there are knowledge gaps in the published literature about its implementation in patients with class Ⅲ obesity [body... BACKGROUND Endoscopic sleeve gastroplasty(ESG) is an effective therapy for class Ⅰ-Ⅱ obesity, but there are knowledge gaps in the published literature about its implementation in patients with class Ⅲ obesity [body mass index(BMI) ≥ 40 kg/m2].AIM To evaluate the safety, clinical efficacy, and durability of ESG in adults with class Ⅲ obesity.METHODS This was a retrospective cohort study that used prospectively collected data on adults with BMI ≥ 40 kg/m2who underwent ESG and longitudinal lifestyle counseling at two centers with expertise in endobariatric therapies from May 2018-March 2022. The primary outcome was total body weight loss(TBWL) at 12 mo. Secondary outcomes included changes in TBWL, excess weight loss(EWL) and BMI at various time points up to 36 mo, clinical responder rates at 12 and 24 mo, and comorbidity improvement. Safety outcomes were reported through the study duration. One-way ANOVA test was performed with multiple Tukey pairwise comparisons for TBWL, EWL, and BMI over the study duration.RESULTS 404 consecutive patients(78.5% female, mean age 42.9 years, mean BMI 44.8 ± 4.7 kg/m2) were enrolled. ESGs were performed using an average of 7 sutures, over 42 ± 9 min, and with 100% technical success. TBWL was 20.9 ± 6.2% at 12 mo, 20.5 ± 6.9% at 24 mo, and 20.3 ± 9.5% at 36 mo. EWL was 49.6 ± 15.1% at 12 mo, 49.4 ± 16.7% at 24 mo, and 47.1 ± 23.5% at 36 mo. There was no difference in TBWL at 12, 15, 24, and 36 mo from ESG. TBWL exceeding 10%, 15%, and 20% was achieved by 96.7%, 87.4%, and 55.6% of the cohort at 12 mo, respectively. Of the cohort with the relevant comorbidity at time of ESG, 66.1% had improvement in hypertension, 61.7% had improvement in type Ⅱ diabetes, and 45.1% had improvement in hyperlipidemia over study duration. There was one instance of dehydration requiring hospitalization(0.2% serious adverse event rate).CONCLUSION When combined with longitudinal nutritional support, ESG induces effective and durable weight loss in adults with class Ⅲ obesity, with improvement in comorbidities and an acceptable safety profile. 展开更多
关键词 Endoscopic sleeve gastroplasty OBESITY BARIATRIC Endobariatrics Class III obesity COMORBIDITIES
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Gastric fundoplication with endoscopic technique:A novel approach for gastroesophageal reflux disease treatment
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作者 Eyad Gadour Anna Carolina Hoff 《World Journal of Gastrointestinal Endoscopy》 2024年第10期557-565,共9页
BACKGROUND Gastric fundoplication with endoscopic technique(GFET)is an innovative approach to managing gastroesophageal reflux disease(GERD).This minimally invasive procedure utilizes the GEN-2 Apollo endosuture devic... BACKGROUND Gastric fundoplication with endoscopic technique(GFET)is an innovative approach to managing gastroesophageal reflux disease(GERD).This minimally invasive procedure utilizes the GEN-2 Apollo endosuture device and Olympus H2T180 gastroscope to perform partial fundoplication by strategically placing Prolene 2-0 sutures at the 11,7,5,1,and 3 o’clock positions around the gastroesophageal junction.AIM To evaluate whether GFET enhances the lower esophageal sphincter function by creating comprehensive plication to improve the barrier against reflux.METHODS This single-center prospective study included patients undergoing GFET.Before beginning GFET,pH metrics and subsequent manometric measurements were obtained.An analysis of variance was performed to determine statistically significant differences between quality of life(QOL)and DeMeester scores at the time of the procedure and 6 and 12 months postoperatively.Pearson’sχ2 test was performed to identify statistically significant differences between categorical variables at the time of the procedure and 6 and 12 months postoperatively.RESULTS Eighteen participants were enrolled(11 males and 7 females;mean age,35 years).More than 70%had an initial Hill grade of IIb.One adverse event was recorded after the procedure.One patient underwent valve reinforcement at 12 months.The mean QOL score was markedly higher at the time of the procedure(39.9±4.0)compared to those at 6 and 12 months postoperatively(P<0.001).Scores at 12 months were slightly higher than those at 6 months.The highest mean QOL score was observed at the time of the procedure,followed by those at 6 and 12 months postoperatively(P<0.001).A similar trend was noted for the mean DeMeester scores(P<0.001).CONCLUSION GFET is a minimally invasive alternative to traditional surgical interventions and endoscopic techniques for managing GERD.Further research is warranted to validate its long-term efficacy and effectiveness over existing treatments. 展开更多
关键词 Gastric fundoplication with endoscopic technique Gastroesophageal reflux disease Therapeutic endoscopy
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The low-latitude sodium layer:comparative data from lidar observations at Hainan,China and São Paulo,Brazil
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作者 Fang Wu Jing Jiao +6 位作者 GuoTao Yang LiFang Du ZhengKuan Liu HaoRan Zheng JiXin Guo ShaoHua Gong YaJun Zhu 《Earth and Planetary Physics》 EI CAS 2025年第1期39-53,共15页
Physical and chemical processes observed in the mesosphere and thermosphere above the Earth’s low latitudes are complex and highly interrelated to activity in the low-latitude ionosphere.Metallic sodium detected by l... Physical and chemical processes observed in the mesosphere and thermosphere above the Earth’s low latitudes are complex and highly interrelated to activity in the low-latitude ionosphere.Metallic sodium detected by lidar can yield clues to dynamic and chemical processes in these spatial layers above the Earth’s atmosphere.This paper is based on sodium layer data collected at two low-latitude stations,one in the northern hemisphere and one in the southern.The low-latitude sodium layer exhibits conspicuous seasonal variations in shape,density,and altitude;these variations are similar between Earth’s hemispheres:sodium layer density at both stations reaches its seasonal maximum in autumn and minimum in summer.However,maximal Na density over Brazil is greater than that over Hainan.Nocturnal variations of Na density above the two low-latitude stations are also similar;at both,maxima are observed before sunrise.Some variations of the Na layer over Brazil that differ from those observed in the northern hemisphere may be related to the South Atlantic Magnetic Anomaly(SAMA)or fountain effect.We suggest that low-latitude Na layer data may provide useful additional evidence that could significantly improve the low-latitude part of the WACCM-Na model. 展开更多
关键词 metallic sodium layer seasonal variation nocturnal variation LIDAR
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Advanced Poly(Lactic Acid)/Thermoplastic Polyurethane Blend-Based Nanocomposites with Carbon Nanotubes and Graphene Nanoplatelets for Shape Memory
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作者 Nayara Koba de Moura Morgado Guilherme Ferreira de Melo Morgado +1 位作者 Erick Gabriel Ribeiro dos Anjos Fabio Roberto Passador 《Journal of Polymer Materials》 2025年第1期95-110,共16页
The continuous improvement in patient care and recovery is driving the development of innovative materials for medical applications.Medical sutures,essential for securing implants and closing deep wounds,have evolved ... The continuous improvement in patient care and recovery is driving the development of innovative materials for medical applications.Medical sutures,essential for securing implants and closing deep wounds,have evolved to incorporate smart materials capable of responding to various stimuli.This study explores the potential of thermoresponsive sutures,made from shape memory materials,that contract upon heating to bring loose stitches closer together,promoting optimal wound closure.We developed nanocomposites based on a blend of poly(lactic acid)(PLA)and thermoplastic polyurethane(TPU)—biopolymers that inherently exhibit shape memory—enhanced with carbon nanotubes(CNT)and graphene nanoplatelets(GN)to improve mechanical performance.PLA/TPU(50/50)nanocomposites were prepared with 1 and 2 wt%GN,as well as hybrid formulations combining 1 wt%CNT with 1 or 2 wt%GN,using a twin-screw extrusion process to form filaments.These filaments were characterized through differential scanning calorimetry(DSC),field emission gun scanning electron microscopy(FEG-SEM),tensile testing,and shape memory assessments.While the PLA/TPU blend is immiscible,TPU enhances the crystallinity(X_(c))of the PLA phase,further increased by the addition of CNT and GN.FEG-SEM images indicate CNTs primarily in the PLA phase and GN in the TPU phase.PLA/TPU with 1 or 2 wt%GN showed the highest potential for suture applications,with a high elastic modulus(~1000 MPa),significant strain at break(~10%),and effective shape recovery(~20%at 55℃ for 30 min).These findings suggest that these nanocomposites can enhance suture performance with controlled shape recovery that is suitable for medical use. 展开更多
关键词 Shape memory polymers poly(lactic acid)(PLA) thermoplastic polyurethane(TPU) carbon nanotubes(CNT) graphene nanoplatelets(GN)
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Use of supervised and unsupervised approaches to make zonal application maps for variable-rate application of crop growth regulators in commercial cotton fields
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作者 ANDREA Maria C.da S. OLIVEIRA Cristiano F.de +7 位作者 MOTA Fabrícia C.M. SANTOS Rafael C.dos RODRIGUES JUNIOR Edilson F. BIANCHI Lucas M. OLIVEIRA Rodrigo S.de GOUVEIA Caio M.de BARBOSA Victor G.S. BISPO E SILVA Marco A. 《Journal of Cotton Research》 2025年第1期1-20,共20页
Background Zonal application maps are designed to represent field variability using key variables that can be translated into tailored management practices.For cotton,zonal maps for crop growth regulator(CGR)applicati... Background Zonal application maps are designed to represent field variability using key variables that can be translated into tailored management practices.For cotton,zonal maps for crop growth regulator(CGR)applications under variable-rate(VR)strategies are commonly based exclusively on vegetation indices(VIs)variability.However,VIs often saturate in dense crop vegetation areas,limiting their effectiveness in distinguishing variability in crop growth.This study aimed to compare unsupervised framework(UF)and supervised framework(SUF)approaches for generat-ing zonal application maps for CGR under VR conditions.During 2022-2023 agricultural seasons,an UF was employed to generate zonal maps based on locally collected field data on plant height of cotton,satellite imagery,soil texture,and phenology data.Subsequently,a SUF(based on historical data between 2020-2021 to 2022-2023 agricultural seasons)was developed to predict plant height using remote sensing and phenology data,aiming to replicate same zonal maps but without relying on direct field measurements of plant height.Both approaches were tested in three fields and on two different dates per field.Results The predictive model for plant height of SUF performed well,as indicated by the model metrics.However,when comparing zonal application maps for specific field-date combinations,the predicted plant height exhibited lower variability compared with field measurements.This led to variable compatibility between SUF maps,which utilized the model predictions,and the UF maps,which were based on the real field data.Fields characterized by much pronounced soil texture variability yielded the highest compatibility between the zonal application maps produced by both SUF and UF approaches.This was predominantly due to the greater consistency in estimating plant development patterns within these heterogeneous field environments.While VR application approach can facilitate product savings during the application operation,other key factors must be considered.These include the availability of specialized machinery required for this type of applications,as well as the inherent operational costs associated with applying a single CGR product which differs from the typical uniform rate applications that often integrate multi-ple inputs.Conclusion Predictive modeling shows promise for assisting in the creation of zonal application maps for VR of CGR applications.However,the degree of agreement with the actual variability in crop growth found in the field should be evaluated on a field-by-field basis.The SUF approach,which is based on plant heigh prediction,demonstrated potential for supporting the development of zonal application maps for VR of CGR applications.However,the degree to which this approach aligns itself with the actual variability in crop growth observed in the field may vary,necessi-tating field-by-field evaluation. 展开更多
关键词 Cotton Site-specific management Crop growth regulator Unsupervised framework Supervised framework Zonal application maps
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Optimizing Activation Temperature of Sustainable Porous Materials Derived from Forestry Residues:Applications in Radar-Absorbing Technologies
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作者 Nila Cecília Faria Lopes Medeiros Gisele Amaral-Labat +6 位作者 Leonardo Iusuti deMedeiros Alan Fernando Ney Boss Beatriz Carvalhoda SilvaFonseca Manuella Gobbo de Castro Munhoz Guilherme F.B.Lenz e Silva Mauricio Ribeiro Baldan Flavia Lega Braghiroli 《Journal of Renewable Materials》 2025年第6期1021-1042,共22页
Biochar,a carbon-rich material derived from the thermochemical conversion of biomass under oxygenfree conditions,has emerged as a sustainable resource for radar-absorbing technologies.This study explores the productio... Biochar,a carbon-rich material derived from the thermochemical conversion of biomass under oxygenfree conditions,has emerged as a sustainable resource for radar-absorbing technologies.This study explores the production of activated biochars from end-of-life wood panels using a scalable and sustainable physical activation method with CO_(2) at different temperatures,avoiding the extensive use of corrosive chemicals and complex procedures associated with chemical or vacuum activation.Compared to conventional chemically or vacuum-activated biochars,the physically activated biochar demonstrated competitive performance while minimizing environmental impact,operational complexity,and energy consumption.Furthermore,activation at 750℃ reduces energy consumption by 14% and 28% compared to activations at 850℃ and 950℃,respectively,emphasizing the cost-effectiveness of this method for large-scale applications.The composite with 15% of biochar embedded in silicon rubber presented good electromagnetic performance,achieving a measured reflection loss(RL)of−37.2 dB at 11.3 GHz with an 8.4 mm thickness and an effective absorption bandwidth(EAB)of 1.25 GHz.These results highlight the potential of biocharsilicone rubber composites as flexible radar-absorbing materials(RAMs)for applications in electromagnetic shielding,anechoic chambers,and Internet of Things(IoT)devices.This study also shows the importance of forestry residues as sustainable precursors for producing low-cost porous carbon materials,aligning with circular economy principles and the United Nations’2030 Agenda for Sustainable Development.This work establishes a framework for scalable,cost-effective,and sustainable biochar production,addressing critical challenges in electromagnetic interference(EMI)mitigation and advancing the global adoption of green technologies. 展开更多
关键词 BIOCHAR forestry residues electromagnetic properties flexible composites
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An innovative approach for integrated airline network and aircraft family optimization 被引量:6
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作者 JoséALEXANDRE T.G.FREGNANI +1 位作者 Bento S.DE MATTOS JoséA.HERNANDES 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2020年第2期634-663,共30页
The determination of optimal aerial transport networks and their associated flight frequencies is crucial for the strategic planning of airlines,as well as for carrying out market research,to establish target markets,... The determination of optimal aerial transport networks and their associated flight frequencies is crucial for the strategic planning of airlines,as well as for carrying out market research,to establish target markets,and for aircraft and crew rostering.In addition,optimum airplane types for the selected networks are crucial to improve revenue and to provide reduced operating costs.The present study proposes an innovative approach to determine the optimal aerial transport network simultaneously with the determination of the optimum fleet for that network,composed of three types of airplanes(network and vehicle integrated design).The network profit is maximized.The passenger’s demands between the airports are determined via a gravitational model.An embedded linear programming solution is responsible for obtaining potential optimal network configurations.The optimum fleet combination is determined from a database of candidate aircraft designs via genetic algorithm.A truly realistic airplane representation is made possible thanks to accurate surrogate models for engine and aerodynamics is adopted.An accurate engine deck encompassing a compression map and an innovative engine weight calculation besides an aerodynamical artificial neural network module enable a high degree of accuracy for the mission analysis.The proposed methodology is applied to obtain the optimum network comprised of twenty main Brazilian airports and corresponding fleet. 展开更多
关键词 Air transport AIRCRAFT DESIGN AIRLINE ECONOMICS AIRLINE network OPTIMIZATION MULTIDISCIPLINARY DESIGN OPTIMIZATION
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Effect of ECAP processing on distribution of second phase particles,hardness and electrical conductivity of Cu-0.81Cr-0.07Zr alloy 被引量:6
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作者 Filipe CALDATTO DALAN Gisele Ferreira de LIMA ANDREANI +3 位作者 Dilermando Nagle TRAVESSA Ilshat Albertovich FAIZOV Svetlana FAIZOVA Kátia Regina CARDOSO 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2022年第1期217-232,共16页
The effect of equal-channel angular pressing(ECAP)processing at room temperature and 300℃on the distribution of the second phase particles and its influence on hardness and electrical conductivity of the commercial C... The effect of equal-channel angular pressing(ECAP)processing at room temperature and 300℃on the distribution of the second phase particles and its influence on hardness and electrical conductivity of the commercial Cu-0.81Cr-0.07Zr alloy were investigated.Microstructural characterization indicated that the area fraction of coarse Cr-rich particles decreased after ECAP processing.This reduction was attributed to the Cr dissolution induced by plastic deformation.The electrical conductivity of the alloy decreased by 12%after 4 ECAP passes at room temperature due to the increase of electrons scattering caused by higher Cr content in solid solution and higher density of defects in the matrix.These results were supported by the reduction of the Cu lattice parameter and by the exothermic reactions,during differential scanning calorimetry(DSC)analysis,observed only in the samples subjected to ECAP processing.Aging heat treatment after ECAP processing promoted an additional hardening effect and the complete recuperation of the electrical conductivity,caused by the re-precipitation of the partially dissolved particles.The better combination of hardness(191 HV)and electrical conductivity(83.5%(IACS))was obtained after 4 ECAP passes at room temperature and subsequent aging at 380℃for 1 h. 展开更多
关键词 ECAP Cu-Cr-Zr alloy second phase particles phase transition
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Spectral classification of water masses under the influence of the Amazon River plume 被引量:2
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作者 Gustavo Souto Fontes Molleri Milton Kampel Evlyn Mrcia Leo de Moraes Novo 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2010年第3期1-8,共8页
The large amount of dissolved and particulate material discharged by the Amazon River into the Equatorial Atlantic Ocean cause distinct spectral response of its waters as compared to the nearby ocean waters. This pape... The large amount of dissolved and particulate material discharged by the Amazon River into the Equatorial Atlantic Ocean cause distinct spectral response of its waters as compared to the nearby ocean waters. This paper shows the application of K-means clustering algorithm for classifying water masses in the region under the Amazon River plume influence according to their spectral behavior. Salinity and temperature data from 67 oceanographic stations were related to Sea-viewing Wide Field-of-view Sensor (SeaWiFS) remote sensing reflectances values and the following bio-optical products: (i) chlorophyll-a concentration, (ii) water attenuation coefficient and (iii) absorption coefficient for dissolved and detrital material. Four different water masses were identified such as: (1) oceanic water, (2) intermediate oceanic water, (3) intermediate river plume water and (4) Amazon River plume water. The spectral behavior of these water masses allowed concluding that the main active optical component of the waters in the region is the colored dissolved organic matter originated mostly from the Amazon River. 展开更多
关键词 ocean color remote sensing amazon river plume spectral behavior cluster analysis
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Monotonic, cyclic and post-cyclic performances of single-helix anchor in residual soil of sandstone 被引量:2
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作者 Jose Antonio Schiavon Cristina de Hollanda Cavalcanti Tsuha Luc Thorel 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2019年第4期824-836,共13页
Helical anchors are commonly used in Brazil for guyed transmission towers subjected to static and cyclic wind loads.In most cases,these anchors are installed in tropical residual soil,a micro-structured material in wh... Helical anchors are commonly used in Brazil for guyed transmission towers subjected to static and cyclic wind loads.In most cases,these anchors are installed in tropical residual soil,a micro-structured material in which the shear strength is provided by soil bonding.During installation of a helical anchor,as the helical plate moves downward into the ground,the soil penetrated is sheared and displaced.Consequently,in this type of soil,anchor installation affects the soil shear strength significantly associated with a bonded structure.However,the cyclic responses of helical anchors in this type of structured soils are rarely reported.To address this problem,tests were conducted in a Brazilian residual soil to investigate the monotonic,cyclic and post-cyclic performances of single-helix anchors.Field tests used two instrumented single-helix anchors installed in this typical residual soil of sandstone,which is frequently observed in large areas in the southern Brazil.The testing results indicate that the disturbance caused by the anchor installation affected the monotonic uplift performance markedly.The results of cyclic loading tests also show no significant degradation of helix bearing resistance and reduced displacement accumulation with increasing load cycles.This is perhaps due to the soil improvement caused by previous loading,which then increases the stiffness response of the anchor. 展开更多
关键词 Helical ANCHORS Tropical residual soil CYCLIC loading Field load tests
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Lactobacillus bulgaricus inhibits colitis-associated cancer via a negative regulation of intestinal inflammation in azoxymethane/dextran sodium sulfate model 被引量:4
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作者 Denise Sayuri Calheiros Silveira Luciana Chain Veronez +3 位作者 Luis Carlos Lopes-Junior Elen Anatriello Mariangela Ottoboni Brunaldi Gabriela Pereira-da-Silva 《World Journal of Gastroenterology》 SCIE CAS 2020年第43期6782-6794,共13页
BACKGROUND Colitis-associated cancer(CAC)accounts for 2%-3%of colorectal cancer(CRC)cases preceded by inflammatory bowel diseases(IBD)such as Crohn's disease and ulcerative colitis.Intestinal microbiota has been r... BACKGROUND Colitis-associated cancer(CAC)accounts for 2%-3%of colorectal cancer(CRC)cases preceded by inflammatory bowel diseases(IBD)such as Crohn's disease and ulcerative colitis.Intestinal microbiota has been reported to play a central role in the pathogenesis of IBD and CAC.Recently,numerous prebiotics and probiotics have being investigated as antitumor agents due to their capacity to modulate inflammatory responses.Previous studies have indicated that lactic acid bacteria could be successfully used in managing sporadic CRC,however little is known about their role in CAC.AIM To investigate the effect of the probiotic Lactobacillus bulgaricus(L.bulgaricus)during the development of an experimental model of colitis associated colon cancer(CAC).METHODS C57BL/6 mice received an intraperitoneal injection of azoxymethane(10 mg/kg),followed by three cycles of sodium dextran sulphate diluted in water(5%w/v).Probiotic group received daily L.bulgaricus.Intestinal inflammation was determined by scoring clinical signs.Cytokines levels were determined from colon and/or tumor samples by ELISA BD OptEIATM kits.The level of significance was set at P<0.05.Graphs were generated and statistical analysis performed using the software GraphPad Prism 6.0.RESULTS L.bulgaricus treatment inhibited of total tumor volume and mean size of tumors.In addition,the probiotic also attenuated the clinical signs of intestinal inflammation inducing a decrease in intestinal and tumor levels of IL-6,TNF-α,IL-17,IL-23 and IL-1β.CONCLUSION Our results suggest a potential chemopreventive effect of probiotic on CAC.L.bulgaricus regulates the inflammatory response and preventing CAC. 展开更多
关键词 Lactobacillus bulgaricus Colitis-associated cancer Colorectal cancer CARCINOGENESIS Probiotics Inflammation
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Artificial equilibrium points and bi-impulsive maneuvers to observe 243 Ida 被引量:1
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作者 Allan Kardec de ALMEIDA Jr Geraldo Magela Couto OLIVEIRA Antonio Fernando Bertachini de Almeida PRADO 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2021年第1期410-423,共14页
In the restricted three-body problem,the traditional Lagrange points L1 and L2 are the only equilibrium points near the asteroid 243 Ida.The thrust generated by a solar sail over a spacecraft enables the existence of ... In the restricted three-body problem,the traditional Lagrange points L1 and L2 are the only equilibrium points near the asteroid 243 Ida.The thrust generated by a solar sail over a spacecraft enables the existence of new artificial equilibrium points,which depend on the position of the spacecraft with respect to the asteroid and the attitude of the solar sail.Such equilibrium points generate new spots to observe the body from above or below the plane of motion.Such points are very good observational locations due to their stationary condition.This work provides a preliminary analysis to observe Ida through the use of artificial equilibrium points as spots combined with transfer maneuvers between them.Such combination can be used to observe the asteroid from more different points of view in comparison to fixed ones.The analyses are made for a spacecraft equipped with a solar sail and capable of performing bi-impulsive maneuvers.The solar radiation pressure is used both to maintain the equilibrium condition and to reduce the costs of the transfers and/or to create transfers with longer duration.This is a new aspect of the present research,because it combines the continuous thrust with initial and final small impulses,which are feasible for most of the spacecraft,because the magnitudes of the impulses are very low.These combined maneuvers may reduce the transfer times of the maneuvers in most of the cases,compared with the maneuvers based only on continuous thrust.Several options involved in these transfers are shown,like to minimize the fuel spent(Dv)as a function of the transfer time or to extend the duration of the travel between the points.Extended transfer times can be useful when observations are required during the transfers. 展开更多
关键词 Artificial equilibrium points ASTRODYNAMICS Orbital transfers Solar radiation pressure Solar sail
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Prototyping low-cost automatic weather stations for natural disaster monitoring 被引量:1
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作者 Gabriel F.L.R.Bernardes Rogerio Ishibashi +2 位作者 Andre A.S.Ivo Valerio Rosset Bruno Y.L.Kimura 《Digital Communications and Networks》 SCIE CSCD 2023年第4期941-956,共16页
Weather events put human lives at risk mostly when people might occupy areas susceptible to natural disasters.Deploying Professional Weather Stations(PWS)in vulnerable areas is key for monitoring weather with reliable... Weather events put human lives at risk mostly when people might occupy areas susceptible to natural disasters.Deploying Professional Weather Stations(PWS)in vulnerable areas is key for monitoring weather with reliable measurements.However,such professional instrumentation is notably expensive while remote sensing from a number of stations is paramount.This imposes challenges on the large-scale weather station deployment for broad monitoring from large observation networks such as in Cemaden—The Brazilian National Center for Monitoring and Early Warning of Natural Disasters.In this context,in this paper,we propose a Low-Cost Automatic Weather Station(LCAWS)system developed from Commercial Off-The-Shelf(COTS)and open-source Internet of Things(IoT)technologies,which provides measurements as reliable as a reference PWS for natural disaster monitoring.When being automatic,LCAWS is a stand-alone photovoltaic system connected wirelessly to the Internet in order to provide real-time reliable end-to-end weather measurements.To achieve data reliability,we propose an intelligent sensor calibration method to correct measures.From a 30-day uninterrupted observation with sampling in minute resolution,we show that the calibrated LCAWS sensors have no statistically significant differences from the PWS measurements.As such,LCAWS has opened opportunities for reducing maintenance costs in Cemaden's observational network. 展开更多
关键词 Wireless automatic weather station Low-cost weather instrumentation Natural disaster monitoring Intelligent sensor calibration Internet of things
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Machine learning algorithm partially reconfigured on FPGA for an image edge detection system 被引量:1
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作者 Gracieth Cavalcanti Batista Johnny Oberg +3 位作者 Osamu Saotome Haroldo F.de Campos Velho Elcio Hideiti Shiguemori Ingemar Soderquist 《Journal of Electronic Science and Technology》 EI CAS CSCD 2024年第2期48-68,共21页
Unmanned aerial vehicles(UAVs)have been widely used in military,medical,wireless communications,aerial surveillance,etc.One key topic involving UAVs is pose estimation in autonomous navigation.A standard procedure for... Unmanned aerial vehicles(UAVs)have been widely used in military,medical,wireless communications,aerial surveillance,etc.One key topic involving UAVs is pose estimation in autonomous navigation.A standard procedure for this process is to combine inertial navigation system sensor information with the global navigation satellite system(GNSS)signal.However,some factors can interfere with the GNSS signal,such as ionospheric scintillation,jamming,or spoofing.One alternative method to avoid using the GNSS signal is to apply an image processing approach by matching UAV images with georeferenced images.But a high effort is required for image edge extraction.Here a support vector regression(SVR)model is proposed to reduce this computational load and processing time.The dynamic partial reconfiguration(DPR)of part of the SVR datapath is implemented to accelerate the process,reduce the area,and analyze its granularity by increasing the grain size of the reconfigurable region.Results show that the implementation in hardware is 68 times faster than that in software.This architecture with DPR also facilitates the low power consumption of 4 mW,leading to a reduction of 57%than that without DPR.This is also the lowest power consumption in current machine learning hardware implementations.Besides,the circuitry area is 41 times smaller.SVR with Gaussian kernel shows a success rate of 99.18%and minimum square error of 0.0146 for testing with the planning trajectory.This system is useful for adaptive applications where the user/designer can modify/reconfigure the hardware layout during its application,thus contributing to lower power consumption,smaller hardware area,and shorter execution time. 展开更多
关键词 Dynamic partial reconfiguration(DPR) Field programmable gate array(FPGA)implementation Image edge detection Support vector regression(SVR) Unmanned aerial vehicle(UAV) pose estimation
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Some Characteristics and Impacts of the Drought and Water Crisis in Southeastern Brazil during 2014 and 2015 被引量:3
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作者 Carlos A. Nobre Jose A. Marengo +2 位作者 Marcelo E. Seluchi L. Adriana Cuartas Lincoln M. Alves 《Journal of Water Resource and Protection》 2016年第2期252-262,共11页
Since the austral summer of 2014 southeastern Brazil has been experiencing one of the most severe droughts in decades. This rainfall deficiency has generated water shortages and a water crisis that have affected popul... Since the austral summer of 2014 southeastern Brazil has been experiencing one of the most severe droughts in decades. This rainfall deficiency has generated water shortages and a water crisis that have affected population and local economies in the metropolitan region of Sao Paulo, the largest megacity in South America. By January 2015, main reservoirs had reached storage levels of only 5% of their 1.3 billion m3 capacity. The meteorological causes of the drought situation were linked to changes in the regional circulation, characterized by a mid-troposphere blocking high that lasted 45 days during the summer of 2014 over southeastern Brazil, something not seen in five decades. The water crisis was aggravated by a combination of lack of rainfall and higher temperatures, the summer of 2014 being the warmest and driest over the Cantareira reservoir system since 1951. Increasing population and water consumption increased vulnerability in the region, and while human-induced warming may not have generated the atmospheric conditions behind the 2014 and 2015 summer droughts in Southeast Brazil, it is more likely that the warm temperatures have affected the severity of the drought and exacerbated the impacts on the population. 展开更多
关键词 DROUGHT Sao Paulo Water Crisis VULNERABILITY
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