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1.
J Environ Manage ; 365: 121644, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38963970

RESUMO

The Earth's atmosphere contains ultrafine particles known as aerosols, which can be either liquid or solid particles suspended in gas. These aerosols originate from both natural sources and human activities, termed primary and secondary sources respectively. They have significant impacts on the environment, particularly when they transform into ultrafine particles or aerosol nanoparticles, due to their extremely fine atomic structure. With this context in mind, this review aims to elucidate the fundamentals of atmospheric-derived aerosol nanoparticles, covering their various sources, impacts, and methods for control and management. Natural sources such as marine, volcanic, dust, and bioaerosols are discussed, along with anthropogenic sources like the combustion of fossil fuels, biomass, and industrial waste. Aerosol nanoparticles can have several detrimental effects on ecosystems, prompting the exploration and analysis of eco-friendly, sustainable technologies for their removal or mitigation.Despite the adverse effects highlighted in the review, attention is also given to the generation of aerosol-derived atmospheric nanoparticles from biomass sources. This finding provides valuable scientific evidence and background for researchers in fields such as epidemiology, aerobiology, and toxicology, particularly concerning atmospheric nanoparticles.

2.
Environ Res ; 238(Pt 1): 117090, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37683791

RESUMO

The present study is aimed to evaluate pesticidal activity and biocompatibility including ecotoxicity of functionalized silica nanoparticles that synthesized by simple, in vitro, green technology principles. Sol-gel method was adopted for the synthesis of silica nanoparticles and was functionalized by Aminopropyltriethoxysilane (APS), characterized and confirmed the uniform, monodispersive, highly stable particles with the size range of 10-200 nm. The synthesized Nano silica was screened against the developmental stages of Spodoptera litura. Pesticidal study revealed that the functionalized nanoparticles were effective against all the life stages of the insect by recording high mortality and the drastic reduction in the larval, pupae, adult emergence, and adult longevity stages. The ecotoxic effect of synthesized nano-silica was tested on soil parameters, growth parameters of Arachis hypogaea, and compatibility with Trichoderma viride. This study revealed there was no toxic effect on soil, growth parameters of Arachis hypogaea, and most significantly the growth of Trichoderma viride was not inhibited. A biocompatibility study was done by using Zebrafish and Rabbit model. The study divulges there was no toxic effect on all the developmental stages of the Embryo. Further, the nanoparticles did not exhibit any dermatotoxicological effect which confirmed no signs and symptoms of inflammation. Nano-silica emerges as a promising eco-friendly and non-toxic substitute for conventional insecticides. Its utilization has the potential to augment both environmental preservation and economic prosperity on a national scale. Furthermore, the integration of silica-based nanoparticles with biocidal agents demonstrates notable biocompatibility and the capacity to hinder bacterial adhesion.


Assuntos
Nanopartículas , Praguicidas , Animais , Coelhos , Dióxido de Silício/toxicidade , Peixe-Zebra , Nanopartículas/toxicidade , Solo
3.
Int J Epidemiol ; 44(5): 1528-36, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25064641

RESUMO

The Manitoba Follow-up Study (MFUS) is Canada's longest running study of cardiovascular disease and ageing. The MFUS cohort consists of 3983 men recruited from the Royal Canadian Air Force at the end of World War II. At entry to the study, 1 July 1948, their mean age was 31 years, with 90% between ages 20 and 39 years. All study members were free of clinical evidence of ischaemic heart disease. The protocol of MFUS was to obtain routine medical examinations from these men at regular intervals over time. The research goal of the study was to examine the role that any abnormalities detected on routine electrocardiograms from apparently healthy men might play in the prediction of subsequent diagnoses of cardiovascular disease. Over the course of 65 years, about 35% of the cohort has documented evidence of ischaemic heart disease. The research focus was expanded in 1996 to explore the roles of physical, mental and social functioning in support of healthy and successful ageing. On 1 July 2013, 429 original cohort members were alive with a mean age of 92 years. Collaborative research with others outside the in-house team is welcomed.


Assuntos
Envelhecimento , Isquemia Miocárdica/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Eletrocardiografia , Seguimentos , Humanos , Masculino , Manitoba , Pessoa de Meia-Idade , Inquéritos e Questionários , Adulto Jovem
4.
Percept Psychophys ; 62(8): 1668-80, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11140187

RESUMO

Learning new phonetic categories in a second language may be thought of in terms of learning to focus one's attention on those parts of the acoustic-phonetic structure of speech that are phonologically relevant in any given context. As yet, however, no study has demonstrated directly that training can shift listeners' attention between acoustic cues given feedback about the linguistic phonetic category alone. In this paper we discuss the results of a training study in which subjects learned to shift their attention from one acoustic cue to another using only category-level identification as feedback. Results demonstrate that training redirects listeners' attention to acoustic cues and that this shift of attention generalizes to novel (untrained) phonetic contexts.


Assuntos
Atenção , Fonética , Prática Psicológica , Percepção da Fala , Adolescente , Adulto , Sinais (Psicologia) , Retroalimentação , Feminino , Humanos , Masculino , Rememoração Mental , Multilinguismo , Espectrografia do Som , Acústica da Fala
5.
J Virol ; 71(4): 3054-61, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9060666

RESUMO

The ZEBRA protein from Epstein-Barr virus (EBV) activates a switch from the latent to the lytic expression program of the virus. ZEBRA, a member of the bZIP family of DNA-binding proteins, is a transcriptional activator capable of inducing expression from viral lytic cycle promoters. It had previously been thought that ZEBRA's capacity to disrupt EBV latency resided primarily in its ability to activate transcription of genes that encode products required for lytic replication. We generated a point mutant of ZEBRA, Z(S186A), that was not impaired in its ability to activate transcription; however, this mutation abolished its ability to initiate the viral lytic cascade. The mutant, containing a serine-to-alanine substitution in the DNA-binding domain of the protein, bound to several known ZEBRA-binding sites and activated transcription from reporters bearing known ZEBRA-responsive promoters but did not disrupt latency in EBV-infected cell lines. Therefore, initiation of the EBV lytic cycle by the ZEBRA protein requires a function in addition to transcriptional activation; a change of serine 186 to alanine in the DNA-binding domain of ZEBRA abolished this additional function and uncovered a new role for the ZEBRA protein in disruption of EBV latency. The additional function that is required for initiation of the lytic viral life cycle is likely to require phosphorylation of serine 186 of the ZEBRA protein, which may influence either DNA recognition or transcriptional activation of lytic viral promoters in a chromatinized viral episome.


Assuntos
Alanina/fisiologia , Proteínas de Ligação a DNA/fisiologia , Herpesvirus Humano 4/fisiologia , Serina/fisiologia , Transativadores/fisiologia , Ativação Transcricional , Proteínas Virais , Latência Viral , Linfócitos B/citologia , Sítios de Ligação , Linhagem Celular , DNA/metabolismo , Proteínas de Ligação a DNA/genética , Expressão Gênica , Genes Reporter , Herpesvirus Humano 4/genética , Humanos , Mutação Puntual , Regiões Promotoras Genéticas , Proteínas Recombinantes de Fusão/genética , Transativadores/genética , Células Tumorais Cultivadas
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