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Iron toxicity resistance strategies in tropical grasses:The role of apoplastic radicular barriers

Journal of Environmental Sciences 2019年第4期31卷 257-266页

作者： Advanio Inacio Siqueira-Silva Camilla Oliveira Rios Eduardo Gusmao pereira Institute of Biological and Health Sciences Federal University of Vicosa (UFV)Campus Florestal Minas Gerais Brazil Federal University of Western Para (UFOPA) University Campus of JurutiPara Brazil Postgradute Program in Management and Conservation of Natural and Agrarian Ecosystems UFV Campus Florestal Florestal Minas Gerais Brazil

The revegetation of mined areas poses a great challenge to the iron ore mining *** initial recovery process in degraded areas might rely on the use of Fe-resistant *** grasses, such as Paspalum densum and Echinochloa crus-galli, show different resistance strategies to iron toxicity; however, these mechanisms are poorly *** Fe-resistance mechanisms and direct iron toxicity as a function of root apex removal were investigated. To achieve this purpose, both grass species were grown for up to 480 hr in a nutrient solution containing 0.019 or 7 mmol/L Fe-EDTA after the root apices had been removed or maintained. Cultivation in the presence of excess iron-induced leaf bronzing and the formation of iron plaque on the root surfaces of both grass species, but was more significant on those plants whose root apex had been removed. Iron accumulation was higher in the roots, but reached phytotoxic levels in the aerial parts as well. It did not hinder the biosynthesis of chloroplastidic pigments. No significant changes in gas exchange and chlorophyll a fluorescence occurred in either grass when their roots were kept intact; the contrary was true for plants with excised root apices. In both studied grasses, the root apoplastic barriers had an important function in the restriction of iron translocation from the root to the aerial plant parts, especially in E. crus-galli. Root apex removal negatively influenced the iron toxicity resistance mechanisms(tolerance in P. densum and avoidance in E. crus-galli).

关键词： Paspalum densum Echinochloa crus-galli Apoplastic barrier Iron toxicity

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Factors Associated with the Infection by <i>Plasmodium vivax</i>in Children and Adolescents from the Brazilian Amazon Basin

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Advances in Infectious Diseases 2020年第2期10卷 140-147页

作者： Rosa Maria Dias Larissa Rodrigues da Costa Agostilina Renata dos Santos da Cruz Ramos Andrea Graças Ferreira Frazã o clá udia Daniele Tavares Dutra Fernanda Maria Lima Moura Isameriliam Rosaulem pereira da Silva José Luiz Fernandes Vieira Faculty of Nutrition Institute of Health Sciences Para Federal University Belem Brazil Pharmacy Faculty Campus Universitario do Guama Para Federal University Belem Brazil

Objective: To investigate the factors associated with malaria vivax infection in children and adolescents from an endemic area in the Eastern portion of the Brazilian Amazon basin. Methods: A case-control study was carried out in the municipality of Anajas, Brazil, from January 2016 to September 2017. Questionnaires were applied to the relative or the legal tutors of children and adolescents with questions regarding social and economic status, educational degree, knowledge about malaria, and the use of protective measures against mosquito bites. Anthropometric measures were performed in children and adolescents. Results: A total of 58 cases and 61 controls were included in the study. Most of the participants were male, eutrophics, and their relatives presented low educational degrees as well as low social and economic status. The knowledge of malaria was limited, but the percentage of individuals using long-lasting insecticidal nets was high. The presence of peri-domiciliary breeding sites for Anopheles vector was the most critical factor for malaria. Conclusion: The occurrence of malaria was associated with low social and economic status, a low educational degree, the unfamiliarity with malaria and the presence of breeding sites for Anopheles mosquito surrounding individual domiciles.

关键词： Infectious Diseases Malaria Epidemiology Risk Factor

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Exploring the drivers of urban expansion in a medium-class urban agglomeration in India using the remote sensing techniques and geographically weighted models

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Geography and Sustainability 2023年第2期4卷 150-160页

作者： Tirthankar Basu Arijit Das Paulo pereira Department of Geography University of Gour BangaMalda 732103West BengalIndia Environmental Management Laboratory Mykolas Romeris University VilniusLithuania

Rapid urbanization urges the immediate attention of policymakers to ensure sustainable city ***-standing the urban growth drivers is essential to address effective strategies for urbanization-related *** work aims to study Raiganj’s urban development and the factors associated with this *** study employed global logistic regression(LR)and geographical weighted logistic regression(GWLR)to explore the role of different *** results showed that the role of the central business district(covariate>-1),commercial market(covariate>-3),and police station(covariate>-4)were significant to the development of new built-up *** the second period,major roads(covariate>-2)and new infrastructures(covariate>-4)became more relevant,particularly in the eastern and southern *** was more accurate in assessing the different fac-tors’impact than *** results obtained are essential to understanding urban expansion in India’s medium-class cities,which is critical to effective policies for sustainable urbanization.

关键词： Drivers Geographically weighted logistic regression (GWLR) Logistic regression LULC Urban growth

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Cooperative Localization and Tracking in Distributed Robot-Sensor Networks

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Tsinghua Science and Technology 2005年第1期10卷 91-101页

作者：张帆 Guilherme S.pereira Vijay Kumar General Robotics Automation Sensing and Perception Laboratory University of Pennsylvania Philadelphia PA USA

This paper addresses the problem of real-time position and orientation estimation of networked mobile robots in two-dimensional Euclidean space with simultaneous tracking of a rigid unknown object based on exteroceptive sensory information extracted from distributed vision systems. The sufficient and necessary conditions for team localization are proposed. A localization and object tracking approach based on statistical operators and graph searching algorithms is presented for a team of robots localized with het- erogeneous sensors. The approach was implemented in an experimental platform consisting of car-like mobile robots equipped with omnidirectional video cameras and IEEE 802.11b wireless networking. The experimental results validate the approach.

关键词： cooperative localization multi-robot formation distributed sensor network sensor data fusion

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Methylation changes at the GNAS imprinted locus in pancreatic cystic neoplasms are important for the diagnosis of malignant cysts

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World Journal of Gastrointestinal Oncology 2020年第9期12卷 1056-1064页

作者： Sandra Faias Marlene Duarte Luísa pereira Paula Chaves Marília Cravo Antonio Dias pereira Cristina Albuquerque Department of Gastroenterology Instituto Português de Oncologia de Lisboa Francisco GentilEPELisboa 1099-023Portugal Faculty of Health Sciences University of Beira InteriorCovilhã6200-506Portugal Unidade de Investigação em Patobiologia Molecular(UIPM) Instituto Português de Oncologia de Lisboa Francisco GentilEPELisboa 1099-023Portugal Centro de Matemática e Aplicações(CMA-UBI) Universidade da Beira InteriorCovilhã6200-506Portugal Department of Pathology Instituto Português de Oncologia de Lisboa Francisco GentilEPELisboa 1099-023Portugal Department of Gastroenterology Hospital BeatrizÂngeloLoures 2674-514Portugal

BACKGROUND Guanine nucleotide-binding protein,alpha stimulating(GNAS)mutations are characteristic of intraductal papillary mucinous neoplasms(IPMNs).Pancreatic ductal adenocarcinomas(PDACs)harboring GNAS mutations originate in *** is a complex imprinted locus that produces five transcripts regulated by differential methylated regions,NESP55,GNASAS,GNASXL,GNAS1A,and *** To evaluate if methylation changes in the differential methylated regions of GNAS locus contributed to malignant progression of pancreatic *** GNAS locus methylation was analyzed in archival pancreatic cyst fluid(PCF)obtained by endoscopic ultrasound with fine-needle aspiration by methylation specific–multiplex ligation dependent probe *** were normalized and analyzed using *** *** Fifty-two PCF samples obtained by endoscopic ultrasound with fine-needle aspiration and previously characterized for KRAS and GNAS mutations were *** final diagnoses were surgical(11)and clinicopathological(41),including 30 benign cysts,14 pre-malignant cyst,and eight malignant *** changes at NESP55,GNASAS,GNAS1A,and especially GNASXL were more frequent in malignant cysts,and NESP55 and GNASAS were useful for diagnosis.A combined variable defined as“GNAS locus methylation changes”was significantly associated with malignancy(6/8 malignant cysts and only 2/20 benign cysts)and improved *** in both maternally(NESP55)and paternally(GNASXL)derived promoters was found in 3/3 *** This is the first study to identify methylation changes in the GNAS locus,improving the diagnosis of malignant pancreatic cysts and suggesting a role in progression to PDAC.

关键词： Intraductal papillary mucinous neoplasms Pancreas cyst Methylation Biomarker GNAS locus Pancreatic neoplasm

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Phenological study of congeneric Myrcia species and clethra scabra in wetland and drained habitats in a Montane Forest

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Journal of Forestry Research 2021年第4期32卷 1419-1427页

作者： Vinícius Londe Jaqueline Alves pereira Hildeberto Caldas de Sousa Lisbon Portugal Ecology of Tropical Biomes Graduate Course Federal University of Ouro PretoOuro PretoMinas Gerais 35400-000Brazil Department of Biodiversity Evolution and EnvironmentFederal University of Ouro PretoOuro PretoMinas Gerais 35400-000Brazil

Although important,phenological studies comparing congeneric species or the same species growing in different habitats are still scarce for the ***,we integrate phylogeny,ecology and biometeorology to verify whether the phenophases of congeneric species Myrcia laruotteana and Myrcia amazonica or clethra scabra differ when their populations inhabit wetland and drained habitats and to determine what abiotic factors affect the vegetative and reproductive phenophases of these species in distinct habitat *** collected data on phenological events of 80 trees for 1 year in Itacolomi State Park,Brazil,and related them to abiotic local *** to our expectation,the phenophases of the congeneric species did not differ between habitats,but the reproductive phenophases of *** did and was greater in drained *** of *** were affected by the depth of the water table and maximum temperature in the wetland ***,precipitation,maximum temperature and relative humidity influenced Myrcia and clethra in the drained *** differences between *** populations suggest that this species is phenotypically plastic and can present distinct phenophases depending on the habitat it *** the other hand,the congeneric Myrcia species may have similar phenophases in distinct habitats because of their shared similarities during their *** study provides a better understanding of the ecology of these species and their adaptations to different abiotic *** of this nature are important in a changing world and can inform strategies for adaptive management.

关键词： Abiotic factors Forest ecology Phenophases Soil types

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Cr（V）involvementin the toxicity pathway of testicular damage

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Asian Journal of Andrology 2002年第2期4卷 153-155页

作者： M.L.pereira T.M.Santos 等 DepartmentofBiology Departmentofchemistry UniversityofAveriro3810－193AveiroPortugal

OBJECTIVE:The functional integrity of the blood-testis barrier (BTB) in male mice exposed to Cr(V) was studied in order to clarify the mechanism underlying testicular injury.;METHODS:Adult male mice were subcutaneously injected repeated doses of 8.02 micromol (0.5 ml) of Cr/*** for 5 days. Animals receiving a similar volume of bis(hydroxyethyl)-aminotris(hydroxymethyl)methane buffer (BT) were used as controls. The animals were sacrificed on day 6 and small fragments of seminiferous tubules, approximately 8-10 mm length, were incised and sutured at both ends. They were exposed in vitro to horseradish peroxidase-containing culture medium for 10 minutes. Tissues were then fixed and processed for ultrastructural studies.;RESULTS:Controls and Cr(V)-treated group resulted in the uptake of the tracer by Sertoli cells. However, the major finding consisted in the permeability of the BTB only in the Cr(V)-group, as evidenced by the presence of the tracer within the junctions between the neighbouring Sertoli cells.;CONclUSIONS:The BTB is disrupted in mice submitted to Cr(V). The permeability of the BTB is a crucial feature to be investigated for the understanding of lesions within the seminiferous tubule.

关键词： Blood-testis barrier Cr(V) Horseradish peroxidase Integrity Spermatogenesis

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Main flexible pavement and mix design methods in Europe and challenges for the development of an European method

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Journal of Traffic and Transportation Engineering(English Edition) 2017年第4期4卷 316-346页

作者： Paulo pereira Jorge Pals Centre for Territory Environment and Construction Uniuersity of Minho Guimaraes 4800-058 Portugal

Pavement and mix design represent one of the key components within the life cycle of a road infrastructure, with links to political, economic, technical, societal and environmental issues. Recent researches related to the characteristics of materials and associated behavior models both for materials and pavement, made it appropriate to consider updating current pavement design methods, and especially in the USA this has already been in process while in Europe uses of the methods developed in the early 1970s. Thus, this paper firstly presents a brief historical overview of pavement design methods, high- lighting early limitations of old empirical methods. Afterwards, French, UK and Shell methods currently in use in Europe will be presented, undeHining their main components in terms of methodology, traffic, climatic conditions and subgrade. The asphalt mix design and modeling in Europe are presented with their inclusion in the pavement design methods. Finally, the main challenges for the development of a European pavement design method are presented as well as the recent research developments that can be used for that method.

关键词： Road pavement Pavement design Mix design Future challenges

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The inception of a Paleotethyan magmatic arc in Iberia

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Geoscience Frontiers 2015年第2期6卷 297-306页

作者： M.F.pereira A.Castro C.Fernández IDL Departamento de Geociências ECT Universidade de évora Departamento de Geología Universidad de Huelva Departamento de Geodinámica y Paleontología Universidad de Huelva

This paper presents a compilation of recent U-Pb （zircon） ages of late Carboniferous-early Permian （LC EP） calc-alkaline batholiths from lberia, together with a petrogenetic interpretation of magma generation based on comparisons with Mesozoic and Tertiary Cordilleran batholiths and experimental melts. Zircon U-Pb ages distributed over the range ca. 315-280 Ma, indicate a linkage between calc-alkaline magmatism, Iberian orocline generation and Paleotethys subduction. It is also shown that Iberian LC-EP calcalkaline batholiths present unequivocal subduction-related features comparable with typical Cordilleran batholiths of the Pacific Americas active margin, although geochemical features were partially obscured by local modifications of magmas at the level of emplacement by country rock assimilation. When and how LC-EP calc-alkaline batholiths formed in Iberia is then discussed, and a new and somewhat controversial interpretation for their sources and tectonic setting （plume-assisted relamination） is suggested. The batholiths are proposed to have formed during the subduction of the Paleotethys oceanic plate （Pangaea self-subduction） and, consequently, they are unrelated to Variscan collision. The origin of the Iberian batholiths is related to the Eurasian active margin and probably represents the inception of a Paleotethvan arc in the core of Pangaea.

关键词： Permo-Carboniferous Calc-alkaline arc-related batholiths Pangaea Paleotethys subduction Variscan and Cimmerian cycles

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Human osteoclast formation and resorptive function on biomineralized collagen

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Bioactive Materials 2022年第2期7卷 241-252页

作者： Daniel de Melo pereira Noel Davison Pamela Habibovic Department of Instructive Biomaterials Engineering MERLN Institute for Technology-Inspired Regenerative MedicineMaastricht University6229 ERMaastrichtThe Netherlands

Biomineralized collagen composite materials pose an intriguing alternative to current synthetic bone graft substitutes by offering a biomimetic composition that closely resembles native *** hypothesize that this composite can undergo cellular resorption and remodeling similar to natural *** investigate the formation and activity of human osteoclasts cultured on biomineralized collagen and pure collagen membranes in comparison to cortical bone *** monocytes/macrophages from peripheral blood differentiate into multinucleated,tartrate-resistant alkaline phosphatase(TRAP)-positive osteoclast-like cells on all *** cells form clear actin rings on cortical bone,but not on biomineralized collagen or pure collagen *** form resorption pits in cortical bone,resulting in higher calcium ion concentration in cell culture medium;however,osteoclast resorption of biomineralized collagen and collagen membranes does not measurably *** of osteoclast enzymes-TRAP,carbonic anhydrase II(CA-II),and cathepsin-K(CTS-K)-is similar on all substrates,despite phenotypic differences in actin ring formation and *** mesh-like structure,relatively low stiffness,and lack of RGD-containing binding domains are likely the factors responsible for preventing formation of stable actin rings on and resorption of(biomineralized)collagen *** insight helps to guide further research toward the optimized design of biomineralized collagen composites as a more biomimetic bone-graft substitute.

关键词： Osteoclastogenesis Osteoclast resorption Biomineralized collagen Intrafibrillar mineral Bone graft substitute

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