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1.
Zhongguo Zhong Yao Za Zhi ; 48(16): 4347-4361, 2023 Aug.
Artículo en Zh | MEDLINE | ID: mdl-37802861

RESUMEN

In this study, visual-near infrared(VNIR), short-wave infrared(SWIR), and VNIR + SWIR fusion hyperspectral data of Polygonatum cyrtonema from different geographical origins were collected and preprocessed by first derivative(FD), second derivative(SD), Savitzky-Golay smoothing(S-G), standard normalized variate(SNV), multiplicative scatter correction(MSC), FD+S-G, and SD+S-G. Three algorithms, namely random forest(RF), linear support vector classification(LinearSVC), and partial least squares discriminant analysis(PLS-DA), were used to establish the identification models of P. cyrtonema origin from three spatial scales, i.e., province, county, and township, respectively. Successive projection algorithm(SPA) and competitive adaptive reweighted sampling(CARS) were used to screen the characteristic bands, and the P. cyrtonema origin identification models were established according to the selected characteristic bands. The results showed that(1)after FD preprocessing of VNIR+SWIR fusion hyperspectral data, the accuracy of recognition models established using LinearSVC was the highest, reaching 99.97% and 99.82% in the province origin identification model, 100.00% and 99.46% in the county origin identification model, and 99.62% and 98.39% in the township origin identification model. The accuracy of province, county, and township origin identification models reached more than 98.00%.(2)Among the 26 characteristic bands selected by CARS, after FD pretreatment, the accuracy of origin identification models of different spatial scales was the highest using LinearSVC, reaching 98.59% and 97.05% in the province origin identification model, 97.79% and 94.75% in the county origin identification model, and 90.13% and 87.95% in the township origin identification model. The accuracy of identification models of different spatial scales established by 26 characteristic bands reached more than 87.00%. The results show that hyperspectral imaging technology can realize accurate identification of P. cyrtonema origin from different spatial scales.


Asunto(s)
Polygonatum , Espectroscopía Infrarroja Corta , Algoritmos , Bosques Aleatorios , Análisis de los Mínimos Cuadrados
2.
Hum Brain Mapp ; 42(1): 80-94, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-32965740

RESUMEN

The dynamics of the human brain span multiple spatial scales, from connectivity associated with a specific region/network to the global organization, each representing different brain mechanisms. Yet brain reconfigurations at different spatial scales are seldom explored and whether they are associated with the neural aspects of brain disorders is far from understood. In this study, we introduced a dynamic measure called step-wise functional network reconfiguration (sFNR) to characterize how brain configuration rewires at different spatial scales. We applied sFNR to two independent datasets, one includes 160 healthy controls (HCs) and 151 patients with schizophrenia (SZ) and the other one includes 314 HCs and 255 individuals with autism spectrum disorder (ASD). We found that both SZ and ASD have increased whole-brain sFNR and sFNR between cerebellar and subcortical/sensorimotor domains. At the ICN level, the abnormalities in SZ are mainly located in ICNs within subcortical, sensory, and cerebellar domains, while the abnormalities in ASD are more widespread across domains. Interestingly, the overlap SZ-ASD abnormality in sFNR between cerebellar and sensorimotor domains was correlated with the reasoning-problem-solving performance in SZ (r = -.1652, p = .0058) as well as the Autism Diagnostic Observation Schedule in ASD (r = .1853, p = .0077). Our findings suggest that dynamic reconfiguration deficits may represent a key intersecting point for SZ and ASD. The investigation of brain dynamics at different spatial scales can provide comprehensive insights into the functional reconfiguration, which might advance our knowledge of cognitive decline and other pathophysiology in brain disorders.


Asunto(s)
Trastorno del Espectro Autista/fisiopatología , Cerebelo/fisiopatología , Corteza Cerebral/fisiopatología , Disfunción Cognitiva/fisiopatología , Conectoma/métodos , Red Nerviosa/fisiopatología , Esquizofrenia/fisiopatología , Tálamo/fisiopatología , Adolescente , Adulto , Trastorno del Espectro Autista/complicaciones , Trastorno del Espectro Autista/diagnóstico por imagen , Cerebelo/diagnóstico por imagen , Corteza Cerebral/diagnóstico por imagen , Niño , Disfunción Cognitiva/diagnóstico por imagen , Disfunción Cognitiva/etiología , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Red Nerviosa/diagnóstico por imagen , Esquizofrenia/complicaciones , Esquizofrenia/diagnóstico por imagen , Tálamo/diagnóstico por imagen , Adulto Joven
3.
Oecologia ; 100(1-2): 177-183, 1994 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28307041

RESUMEN

The searching patterns of the aphid parasitoid Aphidius rosae were analysed at three different spatial scales: leaves, shoots and bushes. Parasitoid females searched aphid-infested leaves and shoots intensively and remained on average more than twice as long on infested than on uninfested shoots. Patch times and oviposition numbers per shoot were highly variable both between females and for different shoot visits within females. However, at the shoot and bush level low oviposition numbers were generally found. The time spent on different behavioural patterns (searching, resting, feeding, host handling) changed significantly during subsequent shoot visits of individual females but oviposition success was not influenced by this change. Parasitoids searched individual leaves and shoots mainly by walking, while moving between shoots occurred exclusively by flight. The travel time between shoots (i.e. flight time) accounted for less than 1% of the residence time in a bush. At the bush level foraging was characterized by a high ability to localize infested shoots and consequently little time was wasted in searching on uninfested shoots. The pattern of resource exploitation of individual females was consistent with the distribution of A. rosae larvae in field samples taken from individual rose bushes.

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