Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 5 de 5
Filtrar
Más filtros












Base de datos
Intervalo de año de publicación
1.
PLoS One ; 19(8): e0306649, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39121086

RESUMEN

This paper explores whether it is feasible to use the RGB color information in images of wheat canopies that were exposed to low temperatures during the growth season to achieve fast, non-destructive, and accurate determination of the severity of any freeze injury it may have incurred. For the study presented in this paper, we compared the accuracy of a number of algorithmic classification models using either meteorological data reported by weather services or the color gradation skewness-distribution from high-definition digital canopy images acquired in situ as inputs against a reference obtained by manually assessing the severity of the freeze injury inflicted upon wheat populations at three experimental stations in Shandong, China. The algorithms we used to construct the models included in our study were based on either K-means clustering, systematic clustering, or naïve Bayesian classification. When analyzing the reliability of our models, we found that, at more than 85%, the accuracy of the Bayesian model, which used the color information as inputs and involved the use of prior data in the form of the reference data we had obtained through manual classification, was significantly higher than that of the models based on systematic or the K-means clustering, which did not involve the use of prior data. It was interesting to note that the determination accuracy of algorithms using meteorological factors as inputs was significantly lower than that of those using color information. We also noted that the determination accuracy of the Bayesian model had some potential for optimization, which prompted us to subject the inputs of the model to a factor analysis in order to identify the key independent leaf color distribution parameters characterizing wheat freeze injury severity. This optimization allowed us to improve the determination accuracy of the model to over 90%, even in environments comprising several different ecological zones, as was the case at one of our experimental sites. In conclusion, our naïve Bayesian classification algorithm, which uses six key color gradation skewness-distribution parameters as inputs and involves the use of prior data in the form of manual assessments, qualifies as a contender for the development of commercial-grade wheat freeze injury severity monitoring systems supporting post-freeze management measures aimed at ensuring food security.


Asunto(s)
Algoritmos , Teorema de Bayes , Color , Triticum , Congelación , Hojas de la Planta , China , Procesamiento de Imagen Asistido por Computador/métodos
2.
Adv Sci (Weinh) ; 11(29): e2306890, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38816931

RESUMEN

In spite of recent advances in the field of undernutrition, current dietary therapy relying on the supply of high protein high calorie formulas is still plagued with transient recovery of impaired organs resulting in significant relapse of cases. This is partly attributed to the inadequacy of current research models in recapitulating clinical undernutrition for mechanistic exploration. Using 1636 Macaca fascicularis monkeys, a human-relevant criterion for determining undernutrition weight-for-age z-score (WAZ), with a cutoff point of ≤ -1.83 is established as the benchmark for identifying undernourished nonhuman primates (U-NHPs). In U-NHPs, pathological anomalies in multi-organs are revealed. In particular, severe dysregulation of hepatic lipid metabolism characterized by impaired fatty acid oxidation due to mitochondria dysfunction, but unlikely peroxisome disorder, is identified as the anchor metabolic aberration in U-NHPs. Mitochondria dysfunction is typified by reduced mito-number, accumulated long-chain fatty acids, and disruption of OXPHOS complexes. Soy peptide-treated U-NHPs increase in WAZ scores, in addition to attenuated mitochondria dysfunction and restored OXPHOS complex levels. Herein, innovative criteria for identifying U-NHPs are developed, and unknown molecular mechanisms of undernutrition are revealed hitherto, and it is further proved that soypeptide supplementation reprogramed mitochondrial function to re-establish lipid metabolism balance and mitigated undernutrition.


Asunto(s)
Modelos Animales de Enfermedad , Hígado , Macaca fascicularis , Desnutrición , Animales , Desnutrición/metabolismo , Hígado/metabolismo , Hígado/efectos de los fármacos , Suplementos Dietéticos , Proteínas de Soja/metabolismo , Proteínas de Soja/farmacología , Metabolismo de los Lípidos/efectos de los fármacos , Masculino
3.
Ying Yong Sheng Tai Xue Bao ; 26(1): 269-77, 2015 Jan.
Artículo en Chino | MEDLINE | ID: mdl-25985679

RESUMEN

Based on the 1961-2010 ground surface data from 90 meteorological stations, this paper analyzed the spatiotemporal change characteristics of agricultural climate resources (e.g. sunshine hours, thermal resources and water) for the growth season of winter wheat and summer maize in Shandong Province. Results indicated that temperature indicators showed a significant rising tendency especially in the winter wheat growth season. Both evapotranspiration and sunshine hours declined obviously, especially for the evapotranspiration in the summer maize growth season, while there was no clear change evidence in rainfall and aridity. Regarding the spatial distribution characteristics, agro-climatic resources presented meridional or zonal increment or decrement in the winter wheat and summer maize growth seasons. In different areas, variation features of agro-climatic resources appeared with distinct differences. In the western Shandong area, temperature indicators showed a slight rising tendency while evapotranspiration and aridity declined significantly. Sunshine hours decreased most significantly in the middle and west southern areas. Precipitation increment was relatively obvious in the winter wheat growth season in the middle and east southern areas and in the summer maize growth season in the middle and southern areas. Thermal resource increases benefited the growth of winter wheat in every phase during the growth period. However, it brought high risks of plant diseases and hot disaster as well. The decrease of sunshine hours was adverse to crop photosynthesis in the growth period while evapotranspiration decrement profited the water retention of soil.


Asunto(s)
Agricultura , Cambio Climático , China , Productos Agrícolas , Ecosistema , Lluvia , Suelo , Luz Solar , Temperatura , Triticum , Agua , Zea mays
4.
Phys Rev E Stat Nonlin Soft Matter Phys ; 82(5 Pt 2): 056115, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21230553

RESUMEN

We investigate the coevolution dynamics of node activities and coupling strengths in coupled chaotic oscillators via a simple threshold adaptive scheme. The coupling strength is synchronous activity regulated, which in turn is able to boost the synchronization remarkably. In the case of weak coupling, the globally coupled oscillators present a highly clustered functional connectivity with a power-law distribution in the tail with γ≃3.1 , while for strong coupling, they self-organize into a network with a heterogeneously rich connectivity at the onset of synchronization but exhibit rather sparse structure to maintain the synchronization in noisy environment. The relevance of the results is briefly discussed.


Asunto(s)
Dinámicas no Lineales , Factores de Tiempo
5.
Di Yi Jun Yi Da Xue Xue Bao ; 25(4): 471-3, 2005 Apr.
Artículo en Chino | MEDLINE | ID: mdl-15837661

RESUMEN

OBJECTIVE: To study the protective effects of the total paeony glycoside (TPG) against global cerebral ischemia-reperfusion injury in gerbils. METHODS: Gerbils models of global cerebral ischemia-reperfusion injury were prepared by bilateral common carotid artery ligation for 12 min followed by 24-hour reperfusion. The effects of TGP on brain edema index, superoxide dismatase (SOD) activity and malonaldehyde (MDA) concentration of the cerebral tissue homogenate and pathology of the brain were examined 24 h after model establishment. RESULTS: Compared with the model group, TPG at the doses of 200 and 400 mg/kg could significantly relieve brain edema, enhance SOD activity and lower MDA concentration in the gerbils. Pathological examination showed that the gerbils with TPG treatment had milder injury of the cells in the hippocampal CA1 region. CONCLUSIONS: TPG has obvious protective effects against global cerebral ischemia-reperfusion injury.


Asunto(s)
Isquemia Encefálica/tratamiento farmacológico , Glicósidos/uso terapéutico , Paeonia/química , Fitoterapia , Daño por Reperfusión/prevención & control , Animales , Gerbillinae , Glicósidos/aislamiento & purificación , Glicósidos/farmacología , Malondialdehído/metabolismo , Sustancias Protectoras/farmacología , Sustancias Protectoras/uso terapéutico , Superóxido Dismutasa/metabolismo
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...