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1.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(12): 3495-9, 2015 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-26964237

RESUMO

Soil organic matter (SOM) is one of the most important indexes to reflect the soil fertility, and soil moisture is a main factor to limit the application of hyperspectral technology in monitoring soil attributes. To study the effect of soil moisture on the accuracy for monitoring SOM with hyperspectral remote sensing and monitor the SOM quickly and accurately, SOM, soil water content (SWC) and soil spectrum for 151 natural soil samples in winter wheat field were measured and the soil samples were classified with the method of traditional classification of SWC and Normalized Difference Soil Moisture Index (NSMI) based on the hyperspectral technology. Moreover, the relationship among SWC, SOM and NSMI were analyzed. The results showed that the accuracy of spectral monitor for SOM among the classifications were significantly different, its accuracy was higher than the soils (5%-25%) which was not classified. It indicated that the soil moisture affected the accuracy for monitoring the SOM with hyperspectral technology and the study proved that the most beneficent soil water content for monitoring the SOM was less 10% and higher 20%. On the other hand, the four models for monitoring the SOM by the hyperspectral were constructed by the classification of NSMI, and its accuracy was higher than the classification of SWC. The models for monitoring the SOM by the classification of NSMI were calibrated with the validation parameters of R², RMSE and RPD, and it showed that the four models were available and reliable to quickly and conveniently monitor the SOM by heperspectral. However, the different classifiable ways for soil samples mentioned in the study were naturally similar as all soil samples were classified again with another way. Namely, there may be another optimal classifiable way or method to overcome and eliminate the SWC effect on the accuracy for monitoring SOM. The study will provide some theoretical technology to monitor the SWC and SOM by remote sensing.

2.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(9): 2490-4, 2014 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-25532351

RESUMO

The simple winter wheat variety was conducted under the low temperature treatment at -2, -4, and -6 °C, the canopy reflectance was measured and the red edge parameters were extracted to study the winter wheat canopy spectral characteristics effected by the low temperature stress and the hyperspectral response to the low temperature stress of winter wheat at jointing stage. The results showed that the canopy reflectance decreased in visible region and increases at near infrared band with the high intensively low temperature stress, and "green peak" was weakened and "red well" was not distinctive. Moreover, the derivate spectrum had the trend of shift to short wavelength direction with the strengthening of low temperature stress and the red edge presented the blue shift. The area of red edge and red edge amplitude exhibit increase. It indicated that the canopy spectrum of winter wheat is sensitive to the low temperature stress, and the hyperspectral technology can be used to monitor the low temperature stress of winter wheat at jointing stage.


Assuntos
Temperatura Baixa , Triticum/fisiologia , Análise Espectral , Estresse Fisiológico
3.
Front Mol Biosci ; 10: 1166333, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37122566

RESUMO

Obesity is associated with various adverse health outcomes. Body fat (BF) distribution is recognized as an important factor of negative health consequences of obesity. Although metabolomics studies, mainly focused on body mass index (BMI) and waist circumference, have explored the biological mechanisms involved in the development of obesity, these proxy composite measures are not accurate and cannot reflect BF distribution, and thus may hinder accurate assessment of metabolic alterations and differential risk of metabolic disorders among individuals presenting adiposity differently throughout the body. Thus, the exact relations between metabolites and BF remain to be elucidated. Here, we aim to examine the associations of metabolites and metabolic pathways with BF traits which reflect BF distribution. We performed systematic untargeted serum metabolite profiling and dual-energy X-ray absorptiometry (DXA) whole body fat scan for 517 Chinese women. We jointly analyzed DXA-derived four BF phenotypes to detect cross-phenotype metabolite associations and to prioritize important metabolomic factors. Topology-based pathway analysis was used to identify important BF-related biological processes. Finally, we explored the relationships of the identified BF-related candidate metabolites with BF traits in different sex and ethnicity through two independent cohorts. Acetylglycine, the top distinguished finding, was validated for its obesity resistance effect through in vivo studies of various diet-induced obese (DIO) mice. Eighteen metabolites and fourteen pathways were discovered to be associated with BF phenotypes. Six of the metabolites were validated in varying sex and ethnicity. The obesity-resistant effects of acetylglycine were observed to be highly robust and generalizable in both human and DIO mice. These findings demonstrate the importance of metabolites associated with BF distribution patterns and several biological pathways that may contribute to obesity and obesity-related disease etiology, prevention, and intervention. Acetylglycine is highlighted as a potential therapeutic candidate for preventing excessive adiposity in future studies.

4.
PLoS One ; 10(1): e115240, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25559638

RESUMO

Determining the influence of soil environmental factors on degradation of Cry1Ac protein from Bt cotton residues is vital for assessing the ecological risks of this commercialized transgenic crop. In this study, the degradation of Cry1Ac protein in leaves and in buds of Bt cotton in soil was evaluated under different soil water content and temperature settings in the laboratory. An exponential model and a shift-log model were used to fit the degradation dynamics of Cry1Ac protein and estimate the DT50 and DT90 values. The results showed that Cry1Ac protein in the leaves and buds underwent rapid degradation in the early stage (before day 48), followed by a slow decline in the later stage under different soil water content and temperature. Cry1Ac protein degraded the most rapidly in the early stage at 35°C with 70% soil water holding capacity. The DT50 values were 12.29 d and 10.17 d and the DT90 values were 41.06 d and 33.96 d in the leaves and buds, respectively. Our findings indicated that the soil temperature was a major factor influencing the degradation of Cry1Ac protein from Bt cotton residues. Additionally, the relative higher temperature (25°C and 35°C) was found to be more conducive to degradation of Cry1Ac protein in the soil and the greater water content (100%WHC) retarded the process. These findings suggested that under appropriate soil temperature and water content, Cry1Ac protein from Bt cotton residues will not persist and accumulate in soil.


Assuntos
Proteínas de Bactérias/metabolismo , Endotoxinas/metabolismo , Gossypium/metabolismo , Proteínas Hemolisinas/metabolismo , Meristema/metabolismo , Folhas de Planta/metabolismo , Temperatura , Água/metabolismo , Toxinas de Bacillus thuringiensis , Proteínas de Bactérias/genética , Endotoxinas/genética , Gossypium/genética , Proteínas Hemolisinas/genética , Meristema/genética , Folhas de Planta/genética , Plantas Geneticamente Modificadas , Proteólise , Solo
5.
PLoS One ; 9(1): e80989, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24404124

RESUMO

In this study, relationships between normalized difference vegetation index (NDVI) and plant (winter wheat) nitrogen content (PNC) and between PNC and grain protein content (GPC) were investigated using multi-temporal moderate-resolution imaging spectroradiometer (MODIS) data at the different stages of winter wheat in Linfen (Shanxi, P. R. China). The anticipating model for GPC of winter wheat was also established by the approach of NDVI at the different stages of winter wheat. The results showed that the spectrum models of PNC passed F test. The NDVI4.14 regression effect of PNC model of irrigated winter wheat was the best, and that in dry land was NDVI4.30. The PNC of irrigated and dry land winter wheat were significantly (P<0.01) and positively correlated to GPC. Both of protein spectral anticipating model of irrigated and dry land winter wheat passed a significance test (P<0.01). Multiple anticipating models (MAM) were established by NDVI from two periods of irrigated and dry land winter wheat and PNC to link GPC anticipating model. The coefficient of determination R(2) (R) of MAM was greater than that of the other two single-factor models. The relative root mean square error (RRMSE) and relative error (RE) of MAM were lower than those of the other two single-factor models. Therefore, test effects of multiple proteins anticipating model were better than those of single-factor models. The application of multiple anticipating models for predication of protein content (PC) of irrigated and dry land winter wheat was more accurate and reliable. The regionalization analysis of GPC was performed using inverse distance weighted function of GIS, which is likely to provide the scientific basis for the reasonable winter wheat planting in Linfen city, China.


Assuntos
Proteínas de Plantas , Tecnologia de Sensoriamento Remoto , Triticum , China , Geografia , Modelos Teóricos , Nitrogênio , Imagens de Satélites , Estações do Ano
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