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1.
Magn Reson Med ; 85(5): 2828-2841, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33231896

RESUMO

PURPOSE: To design a new deep learning network for fast and accurate water-fat separation by exploring the correlations between multiple echoes in multi-echo gradient-recalled echo (mGRE) sequence and evaluate the generalization capabilities of the network for different echo times, field inhomogeneities, and imaging regions. METHODS: A new multi-echo bidirectional convolutional residual network (MEBCRN) was designed to separate water and fat images in a fast and accurate manner for the mGRE data. This new MEBCRN network contains 2 main modules, the first 1 is the feature extraction module, which learns the correlations between consecutive echoes, and the other one is the water-fat separation module that processes the feature information extracted from the feature extraction module. The multi-layer feature fusion (MLFF) mechanism and residual structure were adopted in the water-fat separation module to increase separation accuracy and robustness. Moreover, we trained the network using in vivo abdomen images and tested it on the abdomen, knee, and wrist images. RESULTS: The results showed that the proposed network could separate water and fat images accurately. The comparison of the proposed network and other deep learning methods shows the advantage in both quantitative metrics and robustness for different TEs, field inhomogeneities, and images acquired for various imaging regions. CONCLUSION: The proposed network could learn the correlations between consecutive echoes and separate water and fat images effectively. The deep learning method has certain generalization capabilities for TEs and field inhomogeneity. Although the network was trained only in vivo abdomen images, it could be applied for different imaging regions.


Assuntos
Aprendizado Profundo , Água , Tecido Adiposo/diagnóstico por imagem , Água Corporal/diagnóstico por imagem , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética
2.
Ecotoxicol Environ Saf ; 81: 43-8, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22591725

RESUMO

To study the sublethal effects induced by ethylbenzene and the capability of a freshwater gastropod Bellamya aeruginosa to take up and depurate ethylbenzene, the snail was subjected to two treatments, a 23-day exposure period followed by a 17-day depuration period. Behavioral alteration, namely retraction response, was observed during the exposure period, and the proportion of retracted snails increased under each treatment as the exposure time prolonged but there was no linear relationship between the retracted proportion and the exposure dose. Such behavioral alteration was probably due to the disturbance of membrane permeability stressed by ethylbenzene. Ethylbenzene uptake in unretracted snails was greater than in retracted snails, while the depuration abilities in the two different responses of snails had no significant difference from each other. Because of the limited capability of snails to detoxify ethylbenzene, the depuration was mainly through a slow excretion process and therefore ethylbenzene was still present in the tissue of snail after 17-day depuration. DNA damage was induced significantly in snails exposed to ethylbenzene, and the levels of DNA damage showed positive time-response and dose-response relationships, and moreover the levels of DNA damage had no difference between the two different responses of snails. There was no linear relationship between the level of DNA damage and the amount of residual ethylbenzene in tissue, which may be related to the adaptation mechanism in snail. Overall, the results suggest that the snail has high capability to take up ethylbenzene and low ability to depurate it, and ethylbenzene has potential genotoxicity to snail.


Assuntos
Comportamento Animal/efeitos dos fármacos , Derivados de Benzeno/toxicidade , Mutagênicos/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Dano ao DNA , Água Doce/química , Caramujos/fisiologia
3.
Mycologia ; 102(4): 918-22, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20648758

RESUMO

Hyphodontia septocystidiata and Hyphodontia sinensis are reported as new to science. Hyphodontia septocystidiata has grandinioid to odontioid hymenophore, encrusted cystidia, septocystidia and capitate cystidia and broadly ellipsoid to subglobose thick-walled basidiospores. Hyphodontia sinensis has odontioid hymenophore, leptocystidia and capitate cystidioles and broadly ellipsoid, thin- to slightly thick-walled basidiospores. Descriptions and line drawings are provided for these two new species.


Assuntos
Polyporales/isolamento & purificação , China , Polyporales/classificação , Polyporales/citologia
4.
Front Psychol ; 11: 602736, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33391120

RESUMO

This study adapted the Physical Disability Resilience Scale (PDRS) to Chinese conditions and evaluated the psychometric characteristics of the Chinese version in individuals with physical disability. A total of 438 individuals with physical disability were included in this study. The PDRS was translated to Chinese using a backward translation method. Construct validity, internal consistency reliability, and convergent validity were examined. Confirmatory factor analysis failed to replicate the original five-factor structure of the PDRS. After removing the Spirituality factor and an underperformed item (Item 22), exploratory factor analysis yielded four trait factors (i.e., Emotional and Cognitive Strategies, Physical Activity and Diet, Peer Support, and Support from Family and Friends) and a method-effect factor. A correlated trait-correlated method model that included the four trait factors and a method-effect factor reported better model fit than the four-factor model, which did not consider method effects. The four subscales of the revised PDRS showed adequate internal consistency. The convergent validity of the revised PDRS was established by the moderate-to-strong associations between its four subscales and theoretically related constructs. We conclude that the revised PDRS is a reliable and valid measure in assessing resilience among Chinese people with physical disability.

5.
Chemosphere ; 239: 124794, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31521929

RESUMO

Cadmium (Cd) pollution is considered one of the global environmental issues due to its adverse effects on plant and human health. With the rapid development of nanotechnology and the practical application of engineered nanoparticles (ENPs) in agriculture, the mechanisms underlying the interactions between NPs and heavy metal on their uptake, accumulation, and phytotoxicity in crops are still not fully understood. Therefore, the impact of TiO2 NPs (0, 100, 250 mg/L) and Cd (0, 50 µM) co-exposure on hydroponic maize (Zea mays L.) was determined under two exposure modes. Results showed that root co-exposure to TiO2 NPs and 100 mg/L Cd significantly enhanced Cd uptake and produced greater phytotoxicity in maize than foliar exposure to TiO2 NPs. Meanwhile, plant dry weight and chlorophyll content showed a reduction of 45.3% and 50.5%, respectively, when compared with single Cd treatment. In addition, the accumulation of Ti in shoots and roots increased by 1.61 and 4.29 times, respectively when root exposure to 250 mg/L TiO2 NPs. By contrast, foliar exposure of TiO2 NPs could markedly decrease shoot Cd contents from 15.2% to 17.8% and had a stronger influence on alleviating Cd-induced toxicity via increasing superoxide dismutase (SOD) and glutathione S-transferase (GST) activities and upregulating several metabolic pathways, including galactose metabolism and citrate cycle, alanine, aspartate and glutamate metabolism, as well as glycine, serine and threonine metabolism. This study provides a new strategy for the application of TiO2 NPs in crop safety production in Cd contaminated soils.


Assuntos
Cádmio/toxicidade , Poluentes do Solo/toxicidade , Titânio/farmacologia , Zea mays/efeitos dos fármacos , Aminoácidos/metabolismo , Cádmio/farmacocinética , Clorofila/metabolismo , Produtos Agrícolas/metabolismo , Galactose/metabolismo , Glutationa Transferase/metabolismo , Hidroponia , Nanopartículas Metálicas/administração & dosagem , Nanopartículas Metálicas/química , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Plântula/efeitos dos fármacos , Plântula/metabolismo , Poluentes do Solo/farmacocinética , Superóxido Dismutase/metabolismo , Titânio/administração & dosagem , Titânio/farmacocinética , Zea mays/metabolismo
6.
J Hazard Mater ; 385: 121620, 2020 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-31744724

RESUMO

Microplastics and nanoplastics are emerging pollutants of global concern. However, the understanding of their ecological effects on terrestrial plants is still limited. We conducted the systematic research to reveal the impact of polystyrene nanoplastics (PSNPs) (0.01-10 mg/L) on seed germination and seedling growth of wheat (Triticum aestivum L.). The results showed that PSNPs had no discernible effect on seed germination rate whereas significantly (p < 0.01) increased root elongation by 88.6 %-122.6 % when compared with the control. Similarly, remarkable increases in carbon, nitrogen contents, and plant biomass were also observed after exposure to PSNPs. Moreover, PSNPs could reduce the shoot to root biomass ratio (S:R ratio) of wheat seedlings. Furthermore, the imagings of a 3D laser confocal scanning microscopy (LCSM) and scanning electron microscopy (SEM) indicated that PSNPs were taken up and subsequently down-top transported to shoot. The absorption and accumulation of four micronutrients (Fe, Mn, Cu and Zn) in wheat were generally reduced in varying degrees. Notably, metabolomics analysis revealed that all PSNPs treatments altered the leaf metabolic profiles mainly by regulating energy metabolisms and amino acid metabolisms. These findings are expected to provide new insights into the effects of PSNPs on crop plants.


Assuntos
Germinação/efeitos dos fármacos , Microplásticos/toxicidade , Poliestirenos/toxicidade , Plântula/efeitos dos fármacos , Sementes/efeitos dos fármacos , Triticum/efeitos dos fármacos , Biomassa , Clorofila/metabolismo , Fotossíntese , Raízes de Plantas/metabolismo , Brotos de Planta/metabolismo , Plântula/genética , Triticum/embriologia , Triticum/genética
7.
Environ Sci Pollut Res Int ; 19(6): 2172-8, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22231372

RESUMO

INTRODUCTION: The toxic effect of the oxidation hair dyes on Phanerochaete chrysosporium was investigated by exposure of this fungus in a nitrogen-limited culture medium to various concentrations of the oxidation hair dyes. RESULTS: The results showed that both the size and the dry weight of the mycelial pellets of P. chrysosporium could be reduced when the concentration of the oxidation hair dyes was higher than 300 mg/L. By using the AFLP analysis and the UPGMA dendrogram, the DNA damage of P. chrysosporium by the oxidation hair dyes was also detected. Comparing with that in the control, the percent polymorphism under different concentrations of the oxidation hair dyes increased. In the meantime, the DNA similarity was decreased, which meant that the DNA damage was aggravated with an increase in the concentrations of the oxidation hair dyes. CONCLUSION: Thus, as an environmental pollutant, the oxidation hair dyes have a toxic effect on P. chrysosporium at both cellular and molecular levels.


Assuntos
Tinturas para Cabelo/toxicidade , Phanerochaete/efeitos dos fármacos , Análise do Polimorfismo de Comprimento de Fragmentos Amplificados , Meios de Cultura , Dano ao DNA/efeitos dos fármacos , DNA Fúngico/efeitos dos fármacos , Relação Dose-Resposta a Droga , Poluentes Ambientais/toxicidade , Oxirredução/efeitos dos fármacos
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