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Variations in Atmospheric Electromagnetism and Their Impacts on Mortality Rates in the Southern and Northeastern Regions of Brazil

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Atmospheric and Climate Sciences 2025年第1期15卷 248-274页

作者： Rose Ane Pereira de Freitas Julio Renato Quevedo Marques Reynerth Pereira da Costa Júlia Alves Menezes Isabela de Brito Ferreira Rhavena Barbosa dos santos Ulisses Eugenio Cavalcanti Confalonieri Department of Meteorology Federal University of Pelotas (UFPel) Pelotas Brazil National Observatory (ON) Ministry of Science Rio de Janeiro Brazil Laboratory of Analysis and Development of Indicators for Sustainability (LADIS) Division of Impacts Adaptation and Vulnerability (DIIAV) National Institute for Space Research (INPE) So Jos dos Campos Brazil Department of Parasitology Institute of Biological Sciences Federal University of Minas Gerais (UFMG) Belo Horizonte Brazil Department of Nursing and Medicine Federal University of Viosa (UFV) Viosa Brazil Department of Food Technology Federal Fluminense University (UFF) and Rene Rachou Institute Fiocruz Belo Horizonte Brazil

This study examines the relationship between geomagnetic indices and mortality rates from specific diseases in the Northeast (NE) and Southern (S) regions of Brazil from 1996 to 2020. Solar activity data, including the Ap and Sudden Ionospheric Disturbance (SID) indices, were sourced from the World Data Center, while mortality data were obtained from the Mortality Information System (SIM-DATASUS). Acute Myocardial Infarction (AMI) emerged as the leading cause of mortality, with average death rates of 60.4, 56.8, and 58.3 deaths per 100,000 inhabitants in Pernambuco (PE), Rio Grande do Sul (RS), and Paraná (PR), respectively. Temporal analysis revealed a consistent upward trend in AMI mortality across most states, except for Santa Catarina (SC). Seasonal patterns identified through Principal Component Analysis (PCA) demonstrated that geomagnetic and climatic indices influenced mortality differently across regions and seasons. The Ap geomagnetic index was strongly correlated with higher AMI mortality rates during summer, while the SID index showed greater relevance during winter. A dipole phenomenon was observed, with AMI deaths increasing alongside geomagnetic activity in the S region but showing an inverse relationship in the NE region. These findings highlight the significant influence of geomagnetic variations on public health, particularly cardiovascular mortality. The study underscores the need for further research into the biological mechanisms underlying these associations and recommends the development of early warning systems and targeted preventive measures to mitigate the potential health impacts of geomagnetic disturbances, especially for vulnerable populations.

关键词： Solar Activity Cardiovascular Mortality Geomagnetic Disturbances

Direct Electrochemical Determination of Glyphosate Herbicide Using a Screen-Printed Carbon Electrode Modified with Carbon Black and Niobium Nanoparticles

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Journal of Analysis and Testing 2023年第4期7卷 425-434页

作者： Julia Oliveira fernandes Cassiano Augusto Rolim Bernardino Juliana dos santos fernandes Claudio Fernando Mahler Bernardo Ferreira Braz Luiz Henrique Carpenter dos santos Rodrigo JoséCorrêa Ricardo Erthal Santelli Braulio Soares Archanjo Emerson Schwingel Ribeiro Fernando Henrique Cincotto Departament of Analytical Chemistry Institute of ChemistryFederal University of Rio de JaneiroRio de Janeiro 21941-909Brazil Departament of Civil Engineering COPPEFederal University of Rio de JaneiroRio de Janeiro 21941-598Brazil National Institute of Science&Technology of Bioanalytics(INCTBio) CampinasSão Paulo 13083-862Brazil Departament of Inorganic Chemistry Institute of ChemistryFederal University of Rio de JaneiroRio de Janeiro 21941-909Brazil Unesp National Institute of Alternative Technologies for DetectionToxicological Assessment and Removal of Micropollutants and Radioactives(INCT-DATREM)AraraquaraSão Paulo 14800-060Brazil National Institute of Metrology Quality and TechnologyInmetroAv.Nossa Senhora das Graças50XerémDuque de Caxias 25250-020Brazil

Glyphosate is a herbicide that has been widely used worldwide and is used in agricultural areas to control weeds and unwanted *** sensors developed from different nanomaterials have high efficiency,excellent cost-benefit,and fast analysis time for detecting traces of environmental *** study aimed to produce an electrochemical sensor with disposable screen-printed electrodes based on carbon black modified with niobium nanoparticles to determine glyphosate in aqueous *** morphology,structure and electrochemical performance of the sensor were characterized by scanning electron microscopy,energy-dispersive X-ray spectroscopy,X-ray diffraction and cyclic *** pulse voltammetry in BR buffer solution at pH 5.0 allowed the generation of a method to quantify glyphosate concentration in a linear range of 5.90-172.30μmol/L(1.00-29.13μg/mL),with a limit of detection calculated at 3.07μmol/L(0.52μg/mL).The method efficiently quantified glyphosate in real water samples and showed no interference from K^(+),Na^(+),Ca^(2+),Mg^(2+)ions or thiamethoxam,imidacloprid and carbendazim pesticides.

关键词： Glyphosate Electrochemical sensor Carbon black Niobium nanoparticles

Capacitorless Solid-state Power Filter for Single-phase DC-AC Converters

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CES Transactions on Electrical Machines and Systems 2024年第3期8卷 367-377页

作者： Haitham Kanakri Euzeli C.dos santos Purdue University Electrical and Computer Engineering DepartmentIndianapolisIN46202 USA

Converters rely on passive filtering as a crucial element due to the high-frequency operational characteristics of power *** filtering methods involve a dual inductor-capacitor(LC)cell or an inductor-capacitor-inductor(LCL)***,capacitors are susceptible to wear-out mechanisms and failure ***,the necessity for monitoring and regular replacement adds to an elevated cost of ownership for such *** utilization of an active output power filter can be used to diminish the dimensions of the LC filter and the electrolytic dc-link capacitor,even though the inclusion of capacitors remains an indispensable part of the *** paper introduces capacitorless solid-state power filter(SSPF)for single-phase dc-ac *** proposed configuration is capable of generating a sinusoidal ac voltage without relying on *** proposed filter,composed of a planar transformer and an H-bridge converter operating at high frequency,injects voltage harmonics to attain a sinusoidal output *** design parameters of the planar transformer are incorporated,and the impact of magnetizing and leakage inductances on the operation of the SSPF is *** analysis,supported by simulation and experimental results,are provided for a design example for a single-phase *** total harmonic distortion observed in the output voltage is well below the IEEE 519 *** system operation is experimentally tested under both steady-state and dynamic conditions.A comparison with existing technology is presented,demonstrating that the proposed topology reduces the passive components used for filtering.

关键词： Solid-state power filter(SSPF) Capacitorless topology Active output power filter(AOF) Planar transformer Electrolytic capacitor Lifetime Wear-out mechanisms

Pharmacological therapy used in the elimination of Helicobacter pylori infection:A review

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World Journal of Gastroenterology 2015年第1期21卷 139-154页

作者： Ariolana A dos santos Adriana A Carvalho Department of Pharmacy Federal University of SergipeCampus Lagarto49400-00 LagartoSergipeBrazil

The optimal therapy for Helicobacter pylori(***) infection should combine a high cure rate and a short treatment duration with a favorable side-effect profile and should maintain a low *** strategies have been proposed to increase the *** eradication rate,including the extension of the treatment duration to 14 d,the use of a four-drug regimen(quadruple,sequential,and concomitant treatments),and the use of novel antibiotics,such as ***,triple therapy remains the most widely accepted firstline treatment regimen in Brazil and the United Statesand throughout *** this therapy is limited by resistance to clarithromycin,other therapeutic regimens have been investigated *** review describes the current literature involving studies directly comparing these different therapies and their efficacies.

关键词： Clarithromycin resistant Helicobacter pylori Pepti

Analysis of 12 variants in the development of gastric and colorectal cancers

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World Journal of Gastroenterology 2017年第48期23卷 8533-8543页

作者： Giovanna C Cavalcante Marcos AT Amador Andre M Ribeiro dos santos Darlen C Carvalho Roberta B Andrade Esdras EB Pereira Marianne R fernandes Danielle F Costa Ney PC santos Paulo P Assumpcao Andrea Ribeiro dos santos Sidney santos Laboratório de Genética Humana e Médica Universidade Federal do Pará Núcleo de Pesquisas em Oncologia Universidade Federal do Pará

AIM To evaluate the relation between 12 polymorphisms and the development of gastric cancer(GC) and colorectal cancer(CRC).METHODS In this study,we included 125 individuals with GC diagnosis,66 individuals with CRC diagnosis and 475 cancer-free individuals. All participants resided in the North region of Brazil and authorized the use of their samples. The 12 polymorphisms(in CASP8,CYP2 E1,CYP19 A1,IL1 A,IL4,MDM2,NFKB1,PAR1,TP53,TYMS,UGT1 A1 and XRCC1 genes) were genotyped in a single PCR for each individual,followed by fragment analysis. To avoid misinterpretation due to population substructure,we applied a previously developed set of 61 ancestryinformative markers that can also be genotyped by multiplex PCR. The statistical analyses were performed in Structure v.2.3.4,R environment and SPSS *** After statistical analyses with the control of confounding factors,such as genetic ancestry,three markers(rs79071878 in IL4,rs3730485 in MDM2 and rs28362491 in NFKB1) were positively associated with the development of GC. One of these markers(rs28362491) and the marker in the UGT1 A1 gene(rs8175347) were positively associated with the development of CRC. Therefore,we investigated whether the joint presence of the deleterious alleles of each marker could affect the development of cancer and we obtained positive results in all analyses. Carriers of the combination of alleles RP1 + DEL(rs79071878 and rs28361491,respectively) are at 10-times greater risk of developing GC than carriers of other combinations. Similarly,carriers of the combination of DEL + RARE(rs283628 and rs8175347) are at about 12-times greater risk of developing CRC than carriers of other *** These findings are important for the comprehension of gastric and CRC development,particularly in highly admixed populations,such as the Brazilian population.

关键词： Inflammatory processes Immune response Genomic and cellular stability Gastric cancer Colorectal cancer Amazon

Saturated anisotropic hydraulic conductivity of a compacted lateritic soil

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Journal of Rock Mechanics and Geotechnical Engineering 2018年第5期10卷 986-991页

作者： Roberto Aguiar dos santos Edmundo Rogerio Esquivel Varzea Grande Institute of Engineering Federal University of Mato Grosso Cuiaba Mato Grosso Brazil Sao Carlos School of Engineering University of Sao Paulo Sao Carlos Sao Paulo Brazil

This study focuses on the saturated anisotropic hydraulic conductivity of a compacted lateritic clayey sandy soil. The effects of the molding water content and the confining stress on the anisotropic hydraulic conductivity are investigated. The hydraulic conductivity is measured with a flexible-wall permeameter. Samples are dynamically compacted into the three compaction states of a standard Proctor compaction curve： the dry branch, optimum water content and wet branch. Depending on the molding water content and confining stress, the hydraulic conductivity may increase or decrease. In addition, the results indicate that, when the samples are compacted to the optimum water content, lower hydraulic conductivity is obtained, except at a confining stress equal to 50 kPa. The increase of the confining stress decreases the hydraulic conductivity for each of the evaluated compaction states. In the wet branch, horizontal hy- draulic conductivity is about 8 times higher than the vertical value. The anisotropic hydraulic conduc- tivities of the dry and wet branches decrease when the confining stress increases, and the opposite is observed in the optimum water content state.

关键词： Hydraulic conductivity Anisotropic behavior Lateritic soil Tropical soil Compacted soil

Influence of a non-rotating shoulder on heat generation,microstructure and mechanical properties of dissimilar AA2024/AA7050 FSW joints

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Journal of Materials Science & Technology 2018年第1期34卷 119-127页

作者： Alessandro Barbini Jan Carstensen Jorge F.dos santos Helmholtz-Zentrum Geesthacht Institute of Materials Research Materials Mechanics Solid-State Joining Processes (WMP)

Friction stir welding （FSW） and stationary shoulder friction stir welding （SSFSW） were carried out for the butt joining of dissimilar AA2024-T3 and AA7050-T7651 aluminium alloys with thicknesses of 2 mm. A comparison between the two processes was performed by varying the welding speed while keeping the rotational speed constant, Through the analysis of the force and torque produced during welding and a simple analytical model, it was possible to show that in SSFSW there is more effective coupling with the tool and the heat produced is more efficiently distributed. This process decreases both the welding area and the diffusion at the interface of the two alloys compared with FSW. The minimum microhardness occurred at the advancing side （AS） at the interface between the thermo-mechanically affected zone （TMAZ） and the stir zone （SZ） in both processes, although the decrease was more gradual in SSFSW. This interface is also where all specimens failed for both welding technologies. An increase in tensile strength was measured in SSFSW compared with standard FSW. Furthermore, it was possible to establish the mechanical performance of the material in the fracture zone using digital image correlation.

关键词： Stationary shoulder friction stir welding Friction stir welding Dissimilar welded joints Process analysis Microstructure analysis Mechanical behaviour

Can small-scale altitudinal gradients predict spatial and temporal patterns in tropical forests?

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Journal of Forestry Research 2021年第5期32卷 1854-1865页

作者： Mariana Caroline Moreira Morelli Cléber Rodrigo de Souza Jean Daniel Morel Vinícius Andrade Maia Alisson Borges Miranda santos Kaline fernandes Miranda Rubens Manoel dos santos Forest Sciences Department Federal University of LavrasCampus UniversitárioCx.P.3037LavrasMGCEP 37200-000Brazil Department of Biology Federal University of LavrasCampus UniversitárioLavrasMGCEP 37200-000Brazil

In tropical montane forests,compositional and structural changes are commonly driven by broad-scale altitudinal ***,given the lack of knowledge on small-scale vegetation changes and temporal dynamics,we address the effects of small-scale variations in soil and altitude on tree community structure,temporal dynamics and phylogenetic diversity in a semi-deciduous tropical forest of the Atlantic Forest Domain,southeastern *** 2010 and 2015 we sampled thirty plots of 400 m^(2),set up along an altitudinal gradient between 1000 and 1500 m a.s.I..In each plot,we collected soil samples for chemical and textural *** fitted linear models to test the effects of altitude and soil on community dynamics and phylogenetic *** and soil explained the spatial variation in number of individuals and phylogenetic diversity *** lower to higher altitudes,we found decreasing fertility,increasing tree density and decreasing phylogenetic *** significantly influenced the increases in total biomass(from 240.9 to 255.4 t ha^(-1))and individual biomass(from 0.15 to 0.17 t)recorded in the *** while community temporal dynamics had rates of 1.96%for mortality,1.02%for recruitment,1.61%for biomass loss and 2.81%for biomass gain,none of them were explained by altitude or *** species substitution averaged0.1 in the ***,these results suggest that the small-scale variations in altitude and soil likely determine the conditions and resources that drive community assembly and structure,which are expressed by spatial variations along the altitudinal *** the same time,temporal patterns were not influenced by altitude-related environmental variation,resulting in a similar dynamic behaviour across the gradient,suggesting that broad-scale factors may play a more important role than local ones.

关键词： Fine-scale Semideciduous forests Montane forests Dynamic patterns

Bone marrow-derived mesenchymal stem cells versus adipose-derived mesenchymal stem cells for peripheral nerve regeneration

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Neural Regeneration Research 2018年第1期13卷 100-104页

作者： Marcela fernandes Sandra Gomes Valente Rodrigo Guerra Sabongi Joao Baptista Gomes dos santos Vilnei Mattioli Leite Henning Ulrich Arthur Andrade Nery Maria José da Silva fernandes Division of Hand and Upper Limb Surgery Department of Orthopedics and Traumatology Universidade Federal de Sao Paulo Sao Paulo Brazil Department of Biochemistry Institute of Chemistry Universidade de Sao Paulo Sao Paulo Brazil Division of Neurosciences Department of Neurology and Neurosurgery Universidade Federal de Sao Paulo Sao Paulo Brazil

Studies have confirmed that bone marrow-derived mesenchymal stem cells （MSCs） can be used for treatment of several nervous system diseases. However, isolation of bone marrow-derived MSCs （BMSCs） is an invasive and painful process and the yield is very low. Therefore, there is a need to search for other alterative stem cell sources. Adipose-derived MSCs （ADSCs） have phenotypic and gene expression profiles similar to those of BMSCs. The production of ADSCs is greater than that of BMSCs, and ADSCs proliferate faster than BMSCs. To compare the effects of venous grafts containing BMSCs or ADSCs on sciatic nerve injury, in this study, rats were randomly divided into four groups： sham （only sciatic nerve exposed）, Matrigel （MG; sciatic nerve injury ＋ intravenous transplantation of MG vehicle）, ADSCs （sciatic nerve injury ＋ intravenous MG containing ADSCs）, and BMSCs （sciatic nerve injury ＋ intravenous MG containing BMSCs） groups. Sciatic functional index was calculated to evaluate the function of injured sciatic nerve. Morphologic characteristics of nerves distal to the lesion were observed by toluidine blue staining. Spinal motor neurons labeled with Fluoro-Gold were quantitatively assessed. Compared with sham-operated rats, sciatic functional index was lower, the density of small-diameter fibers was significantly increased, and the number of motor neurons significantly decreased in rats with sciatic nerve injury. Neither ADSCs nor BMSCs significantly improved the sciatic nerve function of rats with sciatic nerve injury,increased fiber density, fiber diameters, axonal diameters, myelin sheath thickness, and G ratios （axonal diameter/fiber diameter ratios） in the sciatic nerve distal to the lesion site. There was no significant difference in the number of spinal motor neurons among ADSCs, BMSCs and MG groups. These results suggest that neither BMSCs nor ADSCs provide satisfactory results for peripheral nerve repair when using MG as the conductor for engraftment.

关键词： nerve regeneration mesenchymal stem cells adipose-derived mesenchmal stem cells sciatic nerve Matrigel sciatic functional index neural regeneration