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1.
Sensors (Basel) ; 23(24)2023 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-38139752

RESUMO

Old plantations are iconic sites, and estimating stand parameters is crucial for valuation and management. This study aimed to estimate stand parameters of a 115-year-old Japanese larch (Larix kaempferi (Lamb.) Carrière) plantation at the University of Tokyo Hokkaido Forest (UTHF) in central Hokkaido, northern Japan, using unmanned aerial vehicle (UAV) photogrammetry. High-resolution RGB imagery was collected using a DJI Matrice 300 real-time kinematic (RTK) at altitudes of 80 and 120 m. Structure from motion (SfM) technology was applied to generate 3D point clouds and orthomosaics. We used different filtering methods, search radii, and window sizes for individual tree detection (ITD), and tree height (TH) and crown area (CA) were estimated from a canopy height model (CHM). Additionally, a freely available shiny R package (SRP) and manually digitalized CA were used. A multiple linear regression (MLR) model was used to estimate the diameter at breast height (DBH), stem volume (V), and carbon stock (CST). Higher accuracy was obtained for ITD (F-score: 0.8-0.87) and TH (R2: 0.76-0.77; RMSE: 1.45-1.55 m) than for other stand parameters. Overall, the flying altitude of the UAV and selected filtering methods influenced the success of stand parameter estimation in old-aged plantations, with the UAV at 80 m generating more accurate results for ITD, CA, and DBH, while the UAV at 120 m produced higher accuracy for TH, V, and CST with Gaussian and mean filtering.


Assuntos
Larix , Animais , Ovinos , Altitude , Japão , Dispositivos Aéreos não Tripulados , Árvores , Fotogrametria , Carbono
2.
Autophagy ; 10(3): 497-513, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24384561

RESUMO

Autophagy is a cellular bulk degradation system for long-lived proteins and organelles that operates during nutrient starvation and is thus a type of recycling system. In recent years, a series of mammalian orthologs of yeast autophagy-related (ATG) genes have been identified; however, the importance of the transcriptional regulation of ATG genes underlying autophagosome formation is poorly understood. In this study, we identified several ATG genes, including the genes ULK1, MAP1LC3B, GABARAPL1, ATG13, WIPI1, and WDR45/WIPI4, with elevated mRNA levels in thapsigargin-, C2-ceramide-, and rapamycin-treated as well as amino acid-depleted HeLa cells except for MAP1LC3B mRNA in rapamycin-treated HeLa cells. Rapamycin had a weaker effect on the expressions of ATG genes. The increase in WIPI1 and MAP1LC3B mRNA was induced prior to the accumulation of the autophagy marker protein MAP1LC3 in the thapsigargin- and C2-ceramide-treated A549 cells. By counting the puncta marked with MAP1LC3B in HeLa cells treated with different autophagy inducers, we revealed that the time-dependent mRNA elevation of a specific set of ATG genes was similar to that of autophagosome accumulation. The transcriptional attenuation of WIPI1 mRNA using RNA interference inhibited the puncta number in thapsigargin-treated HeLa cells. Remarkably, increases in the abundance of WIPI1 mRNA were also manifested in thapsigargin- and C2-ceramide-treated human fibroblasts (WI-38 and TIG-1), human cancer cells (U-2 OS, Saos-2, and MCF7), and rodent fibroblasts (Rat-1). Taken together, these results suggest that the detection of WIPI1 mRNA is likely to be a convenient method of monitoring autophagosome formation in a wide range of cell types.


Assuntos
Autofagia/genética , Proteínas de Transporte/genética , Proteínas de Membrana/genética , Proteínas Associadas aos Microtúbulos/genética , Fagossomos/metabolismo , RNA Mensageiro/metabolismo , Sirolimo/farmacologia , Autofagia/fisiologia , Proteínas Relacionadas à Autofagia , Linhagem Celular , Expressão Gênica , Células HeLa , Humanos , Proteínas Associadas aos Microtúbulos/metabolismo , Fagossomos/genética , Estabilidade de RNA/fisiologia
3.
J Biochem Mol Toxicol ; 26(11): 445-53, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23129091

RESUMO

Anthocyanidins, which are polyphenols that are believed to be effective for preventing cancer, are composed of a basic structure of the plant pigment anthocyanin. In this study, we investigated the biological activity of anthocyanidins, including delphinidin, against HeLa cells. The cytotoxicity observed in the anthocyanidins-treated cells was well correlated with the inhibitory effects of anthocyanidins on c-Jun-dependent transcriptional activity. Remarkably, anthocyanidin induced autophagosome formation but lacked the ability to induce apoptosis. Notably, delphinidin enhanced autolysosome formation as well as autophagosome formation. Delphinidin treatment resulted in the accumulation of the lipidated form of Map1lc3b protein in an Atg5-dependent manner in mouse embryonic fibroblasts. Finally, we revealed that the cytotoxicity induced by delphinidin was more severe in Atg5-deficient mouse embryonic fibroblasts than in wild-type cells. Taken together, these results indicate that the cytotoxicity induced by delphinidin was accompanied by autophagy and delphinidin-induced autophagy exerted a cell protective role.


Assuntos
Antocianinas/farmacologia , Anticarcinógenos/farmacologia , Autofagia/efeitos dos fármacos , Lisossomos/efeitos dos fármacos , Fagossomos/efeitos dos fármacos , Animais , Proteína 5 Relacionada à Autofagia , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Embrião de Mamíferos/citologia , Embrião de Mamíferos/metabolismo , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Células HeLa , Humanos , Lisossomos/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos , Camundongos Knockout , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Concentração Osmolar , Fagossomos/metabolismo , Proteínas Recombinantes de Fusão/metabolismo
4.
J Environ Manage ; 88(4): 784-95, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17629393

RESUMO

Tropical deforestation is occurring at an alarming rate, threatening the ecological integrity of protected areas. This makes it vital to regularly assess protected areas to confirm the efficacy of measures that protect that area from clearing. Satellite remote sensing offers a systematic and objective means for detecting and monitoring deforestation. This paper examines a spectral change approach to detect deforestation using pattern decomposition (PD) coefficients from multitemporal Landsat data. Our results show that the PD coefficients for soil and vegetation can be used to detect deforestation using change vector analysis (CVA). CVA analysis demonstrates that deforestation in the Kinabalu area, Sabah, Malaysia has significantly slowed from 1.2% in period 1 (1973 and 1991) to 0.1% in period 2 (1991 and 1996). A comparison of deforestation both inside and outside Kinabalu Park has highlighted the effectiveness of the park in protecting the tropical forest against clearing. However, the park is still facing pressure from the area immediately surrounding the park (the 1 km buffer zone) where the deforestation rate has remained unchanged.


Assuntos
Recreação , Árvores , Malásia , Comunicações Via Satélite
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