137 research outputs found

    Implications of iron nanoparticles in spontaneous coal combustion and the effects on climatic variables

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    Atmosphere, water, and soil contamination with toxic compounds is a recurrent issue due to environmental disasters, coal burning, urbanization, and industrialization, allf of which have contributed to soil contamination over the decades. Consequently, understanding of the nanomineralogy and potential hazardous elements (PHEs) in coal area soil are always a vital topic since contaminated soil can affect the environment, agricultural safety, and human health. Colombian coal mining in the La Guajira zone has been usually been related with important health and ecological effects. Coalmine rejects from active and/or abandoned operations are causes of high intensities of potential hazardous elements (PHEs) and nanoparticles (NPs, minerals and/or amorphous compounds). Although these pollutants can be reduced by sorption to NPs, in this study was recognized an analytical procedure for understand distribution of PHEs and their relationship to iron NPs(Fe-NPs) was recognized. Non and poorrly crystalline Fe-NPs performances as the major PHEs association. This complex interaction is constant and efficient in resolving PHEs in proportions above monitoring quantities. The indefinite basis of PHEs in Colombian (La Guajira area) coalmine rejects sources results in years-long leaching of PHEs into rivers and drainages. The iron-clays and their great geomobility interfere the mitigating character that Fe hydr/oxides alone show through adsorption of PHEs and their control in spontaneous coal combustion (SCC) zones. This can have significant consequences to the probable availability of several pollutants (e.g. drinking water). The new results presented in this study add novel viewpoints into the description of Fe-NPs and its incidence in SCC areas. The methodology utilized in this work can be applied as a supplementary technique to evaluate the influence of coalmining actions on ecological and human health

    Multiple hazardous elements in nanoparticulate matter from a Caribbean industrialized atmosphere

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    Modern microscopy studies are capable of revealing ultra-fine particles (UFPs) and nanoparticles (NPs) that are produced in the processes related to traffic vehicular, industrial, metropolitan, and marine aerosol dry deposition in the coastal zones. Especially, secondary aerosol passages complexes categories of NPs and UFPs, which can be accumulated on construction compounds and by dry deposition, encourages multiples monuments deterioration routes. The advanced electron microscopies method is one of the most utilized in environmental studies. Between the different industrial areas in the world, the Caribbean area is the most relevant symbols of air quality due to climatic conditions with strong winds, but this study shows that regionally the most industrialized region does not have an adequate air quality. In the present work, electron microscopy analyses are used to describe of the extent of ultra-fine particle and nanoparticles in walls in contact to weathering. Numerous phases were recognized by advanced mineralogy methods. Thanks to the new analytical procedure it was feasible to understand NPs and UFPs; the occurrence of potential hazardous elements (PHEs), most of them as minerals but also combined in multiple accumulations with Al–Cr–Fe–K–Mg–Pb–Si–Ti–Zn amorphous; and carbonaceous phases

    Metal-enriched nanoparticles and black carbon: A perspective from the Brazil railway system air pollution

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    Having a better understanding of air pollutants in railway systems is crucial to ensure a clean public transport. This study measured, for the first time in Brazil, nanoparticles (NPs) and black carbon (BC) on two ground-level platforms and inside trains of the Metropolitan Area of Porto Alegre (MAPA). An intense sampling campaign during thirteen consecutive months was carried out and the chemical composition of NPs was examined by advanced microscopy techniques. The results showed that highest concentrations of the pollutants occur in colder seasons and influenced by variables such as frequency of the trains and passenger densities. Also, internal and external sources of pollution at the stations were identified. The predominance of NPs enriched with metals that increase oxidative stress like Cd, Fe, Pb, Cr, Zn, Ni, V, Hg, Sn, and Ba both on the platforms and inside trains, including Fe-minerals as hematite and magnetite, represents a critical risk to the health of passengers and employees of the system. This interdisciplinary and multi-analytical study aims to provide an improved understanding of reported adverse health effects induced by railway system aerosols

    Pathogen- and Host-Directed Antileishmanial Effects Mediated by Polyhexanide (PHMB)

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    BACKGROUND:Cutaneous leishmaniasis (CL) is a neglected tropical disease caused by protozoan parasites of the genus Leishmania. CL causes enormous suffering in many countries worldwide. There is no licensed vaccine against CL, and the chemotherapy options show limited efficacy and high toxicity. Localization of the parasites inside host cells is a barrier to most standard chemo- and immune-based interventions. Hence, novel drugs, which are safe, effective and readily accessible to third-world countries and/or drug delivery technologies for effective CL treatments are desperately needed. METHODOLOGY/PRINCIPAL FINDINGS:Here we evaluated the antileishmanial properties and delivery potential of polyhexamethylene biguanide (PHMB; polyhexanide), a widely used antimicrobial and wound antiseptic, in the Leishmania model. PHMB showed an inherent antileishmanial activity at submicromolar concentrations. Our data revealed that PHMB kills Leishmania major (L. major) via a dual mechanism involving disruption of membrane integrity and selective chromosome condensation and damage. PHMB's DNA binding and host cell entry properties were further exploited to improve the delivery and immunomodulatory activities of unmethylated cytosine-phosphate-guanine oligodeoxynucleotides (CpG ODN). PHMB spontaneously bound CpG ODN, forming stable nanopolyplexes that enhanced uptake of CpG ODN, potentiated antimicrobial killing and reduced host cell toxicity of PHMB. CONCLUSIONS:Given its low cost and long history of safe topical use, PHMB holds promise as a drug for CL therapy and delivery vehicle for nucleic acid immunomodulators

    Communication in health practices: integrative literature review

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    Objectivethis study aims to describe the main thematic axes explored in the communication field in health practices in the scenarios of the Unified Health System (SUS). Methodintegrative literature review conducted by means of search for articles in the databases Latin American Literature on Health Sciences (LILACS), International Literature on Health Sciences (MedLine), and Science Direct, using the descriptors: health communication or communication. A crossing of the descriptors communication and health education was provided. Resultfour themes were constructed: 1) communication to establish relationships between health professionals and users; 2) (in)communication: barriers to the communicative act, 3) communication and health professional education; and 4) communicative health models: search for the dialogic model. Conclusionby understanding dialogic communication, which must be observed in communication, the new requirements posed by the legalization of SUS have shown weaknesses of the single-line and vertical communication model and the need to provide health professionals, since the undergraduate course, with knowledge that enable dialogic communication practices. The challenge of reflective and participatory experiences in the various health care settings still remains, in order to promote a sharing of knowledge that leads to understanding between the interlocutors involved in the communicative act.Objetivoeste artigo tem por objetivo descrever os principais eixos temáticos explorados no campo da comunicação nas práticas em saúde nos cenários do Sistema Único de Saúde (SUS). Métodorevisão integrativa da literatura realizada a partir da busca de artigos nas bases de dados Literatura Latino-Americana em Ciências da Saúde (Lilacs), Literatura Internacional em Ciências da Saúde (MedLine) e Science Direct, utilizando os descritores: comunicação em saúde ou comunicação. Procedeu-se ao cruzamento dos descritores comunicação e educação em saúde. Resultadoforam construídas quatro temáticas: 1) a comunicação no estabelecimento de relações entre profissionais da saúde e usuários; 2) (des)comunicação: barreiras ao ato comunicativo; 3) comunicação e formação do profissional da saúde; e 4) modelos comunicativos em saúde: a busca pelo modelo dialógico. Conclusãoa partir do entendimento da comunicação dialógica, que deve estar presente na comunicação, as novas demandas da legalização do SUS vêm mostrando fragilidades do modelo unilinear e verticalizado de comunicação e a necessidade de instrumentalizar os profissionais da saúde, desde a graduação, com saberes que proporcionem práticas comunicativas dialógicas. Persiste o desafio de vivências reflexivas e participativas nos vários cenários de assistência à saúde, de forma a promover um compartilhamento de saberes que conduza ao entendimento entre os interlocutores envolvidos no ato comunicativo.Universidade Federal de PernambucoUniversidade Federal de Pernambuco Departamento de FonoaudiologiaUniversidade Federal de São Paulo (UNIFESP) Centro de Desenvolvimento do Ensino Superior em SaúdeUniversidade Federal de Pernambuco Departamento de EnfermagemUNIFESP, Centro de Desenvolvimento do Ensino Superior em SaúdeSciEL

    Consistent patterns of common species across tropical tree communities

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    Trees structure the Earth’s most biodiverse ecosystem, tropical forests. The vast number of tree species presents a formidable challenge to understanding these forests, including their response to environmental change, as very little is known about most tropical tree species. A focus on the common species may circumvent this challenge. Here we investigate abundance patterns of common tree species using inventory data on 1,003,805 trees with trunk diameters of at least 10 cm across 1,568 locations1,2,3,4,5,6 in closed-canopy, structurally intact old-growth tropical forests in Africa, Amazonia and Southeast Asia. We estimate that 2.2%, 2.2% and 2.3% of species comprise 50% of the tropical trees in these regions, respectively. Extrapolating across all closed-canopy tropical forests, we estimate that just 1,053 species comprise half of Earth’s 800 billion tropical trees with trunk diameters of at least 10 cm. Despite differing biogeographic, climatic and anthropogenic histories7, we find notably consistent patterns of common species and species abundance distributions across the continents. This suggests that fundamental mechanisms of tree community assembly may apply to all tropical forests. Resampling analyses show that the most common species are likely to belong to a manageable list of known species, enabling targeted efforts to understand their ecology. Although they do not detract from the importance of rare species, our results open new opportunities to understand the world’s most diverse forests, including modelling their response to environmental change, by focusing on the common species that constitute the majority of their trees.Publisher PDFPeer reviewe
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