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1.
Ying Yong Sheng Tai Xue Bao ; 34(11): 2919-2928, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37997402

RESUMEN

Vegetation plays a critical role in the water and carbon cycling and energy flow, serving as an indicator for regulating land carbon balance and reflecting climate change and human activities. We analyzed the spatiotemporal variations of normalized difference vegetation index (NDVI) during the growing season in southern Jiangxi from 2000 to 2020, using statistical methods, including the Mann-Kendall test, Theil-Sen Median analysis, Hurst index, and coefficient of variation. We employed the geodetector model to comprehensively assess the impacts of climate, topography, soil and human factors on spatial differentiation of vegetation NDVI. The results showed NDVI exhibited an upward fluctuating trend with a rate of 0.003 per year from 2000 to 2020. The proportion of high-grade and medium-high-grade NDVI areas were 55.8% and 41.9%, respectively, while the areas with low and relatively low fluctuations accounted for 92.3%. The proportions of areas showing extremely significant improvement and significant improvement were 40.4% and 19.4%, respectively. In contrast, the combined proportion of areas displaying extremely significant degradation and significant degradation was only 2.2%. The proportions of areas demonstrating continuous improvement and future improvement were 28.0% and 60.2%, respectively. Elevation, precipitation, relative humidity, temperature, landform type, land use type, population density, and nighttime light were identified as the major factors for the vairations of NDVI in the study area, followed by slope, soil type, and GDP, while slope aspect and vegetation type had indirect influence. Throughout the study period, NDVI in southern Jiangxi was overall stable, with future changes primarily indicating improvement. Notably, human factors such as land use type, population density, and nighttime light index exhibited an upward trend in their impacts on NDVI.


Asunto(s)
Cambio Climático , Suelo , Humanos , China , Temperatura , Carbono , Ecosistema
2.
Biosensors (Basel) ; 13(2)2023 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-36832030

RESUMEN

Transition metal oxides have garnered a lot of attention in the field of electrocatalysis along with their unique crystal structure and excellent catalytic properties. In this study, carbon nanofibers (CNFs) decorated with Mn3O4/NiO nanoparticles were made using electrospinning and calcination. The conductive network constructed by CNFs not only facilitates electron transport, but also provides landing sites for nanoparticles, thus reducing nanoparticle aggregation and exposing more active sites. Additionally, the synergistic interaction between Mn3O4 and NiO improved electrocatalytic capacity for glucose oxidation. The Mn3O4/NiO/CNFs modified glassy carbon electrode shows satisfactory results in terms of linear range and anti-interference capability for glucose detection, suggesting that the constructed enzyme-free sensor has a promising application in clinical diagnosis.


Asunto(s)
Nanofibras , Nanopartículas , Carbono/química , Nanofibras/química , Níquel , Glucosa , Nanopartículas/química , Óxidos , Electrodos , Técnicas Electroquímicas/métodos
3.
Ying Yong Sheng Tai Xue Bao ; 33(7): 1948-1956, 2022 Jul.
Artículo en Chino | MEDLINE | ID: mdl-36052799

RESUMEN

It is difficult to obtain long time series of high spatial resolution remote sensing images in southern China because of the complex terrain and frequent cloudy and rainy weather. In contrast, the spatio-temporal fusion can sychonorously obtain remote sensing data with high spatial-temporal resolution, which is beneficial to extract forest vegetation type information. With Xingguo County of Jiangxi Province as the study area, we fused the Landsat8 OLI and GF-1 WFV images with high spatial resolution with high temporal resolution of MODIS09 A1 image on the basis of enhanced spatial and temporal adaptive reflectance fusion model (ESTARFM), reconstructed the time series data of ESTARFM_Landsat8 EVI and ESTARFM_GF-1 EVI with 8 d step of enhanced vegetation index (EVI), obtained the phenology (PH) characteristics, and identified the forest vegetation types by using random forest classification model. The results showed that the correlation coefficients between the fusion data of ESTARFM_Landsat8 EVI and ESTARFM_GF-1 EVI and the real images were all greater than 0.7, and had good consistency in spatial distribution, which could be used to supplement the missing data with high spatial resolution. The extraction accuracy of random forest classification with different combination modes was EVI+PH>EVI>PH and the classification accuracy of fusion data GF-1 was higher than that of Landsat8. A total of 43 variables were selected as the optimal feature variables for classification. The overall accuracy and Kappa coefficient were 95.6% and 94.9%, respectively, including 37 sequential EVI values and 6 phenological feature information. The sequential EVI data contributed more to the identification of forest vegetation types, while the phenological feature information was beneficial to improve the classification accuracy. The ESTARFM fusion algorithm was suitable for GF-1 and MODIS data, which could solve the problem of insufficient long-term sequence of high spatial resolution images. The GF-1 temporal fusion images had high accuracy in the identification of forest vegetation types in southern China under complex terrain and frequent cloudy and rainy weather.


Asunto(s)
Monitoreo del Ambiente , Lluvia , Algoritmos , China , Monitoreo del Ambiente/métodos
4.
J Cardiothorac Surg ; 16(1): 314, 2021 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-34702337

RESUMEN

BACKGROUND: Bulla is a common cause of primary spontaneous pneumothorax. Video-assisted thoracoscopic surgery (VATS) through the lateral chest wall is a common surgical approach and an effective treatment for this condition, but postoperative incision scars affect the aesthetic outcome. VATS via axillary approach can hide the scar in the axilla, and the wound in its natural state is invisible; this greatly improves the cosmetic appearance. To our knowledge, this is the first report of VATS-based bullectomy via the axillary approach in a patient with spontaneous pneumothorax. CASE PRESENTATION: A 20-year-old female patient was admitted to the hospital with a 2-day history of chest tightness and chest pain. Plain chest computed tomography showed right spontaneous pneumothorax, lung compression of 75%, and right pulmonary bulla. After complete preoperative examination, VATS bullectomy via right axillary approach was performed. During the operation, a bulla measuring about 4 × 4 cm was found at the apex of the right lung and resected. The incision healed well, and the patient was discharged after surgery. CONCLUSIONS: VATS bullectomy via axillary approach is safe and feasible, with the incision hidden in the axilla and not visible in the natural state. This method leaves no scar on the chest wall and has good cosmetic outcome.


Asunto(s)
Neumotórax , Adulto , Axila/cirugía , Vesícula/diagnóstico por imagen , Vesícula/cirugía , Femenino , Humanos , Pulmón , Neumotórax/diagnóstico por imagen , Neumotórax/cirugía , Cirugía Torácica Asistida por Video , Adulto Joven
5.
Ying Yong Sheng Tai Xue Bao ; 30(6): 1885-1892, 2019 Jun.
Artículo en Chino | MEDLINE | ID: mdl-31257760

RESUMEN

Carbon density is one of the important indicators for carbon sequestration capacity in forest ecosystems. The analysis of spatial variation in forest carbon density can provide scientific basis for management of forest carbon sink. We investigated the carbon density of Pinus massoniana forest in Jiangxi Province. Based on plot investigation and meaurement of sample carbon content, the spatial autocorrelation and distribution of carbon density were analyzed and explored respectively by using global Moran I, local Moran I and geostatistics. Results from the global Moran I showed that ecosystem carbon density had significant positive spatial autocorrelation and its autocorrelation decreased with the increase of distance. Ecosystem carbon density had no spatial autocorrelation when the distance exceeded 400 km. The spatial distribution of ecosystem carbon density changed from aggregated distribution to random distribution with the increase of distance. Results from the local Moran I showed that the local spatial distribution of ecosystem carbon density was not uniform, and the difference of local spatial distribution gradually increased with the increase of distance. The fitting results of semi-variogram models showed that the spherical model was the best fitting model for the estimation of ecosystem carbon density. The ratio of nugget to sill was 0.36, indicating mode-rate spatial correlation of carbon density. The ecosystem carbon density based on kriging spatial interpolation mainly concentrated in the range of 85.14-153.52 t·hm-2. The spatial distribution regularity was generally low in middle region and high in peripheral region, which was consistent with the terrain characteristics of the study area.


Asunto(s)
Carbono/análisis , Monitoreo del Ambiente , Bosques , Pinus/química , China , Ecosistema , Suelo , Árboles
6.
Cancer Cell Int ; 18: 210, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30574019

RESUMEN

BACKGROUND: Osteosarcoma (OS) is the most common bone malignancy prevalent in children and young adults. MicroRNA-133b (miR-133b), through directly targeting the fibroblast growth factor receptor 1 (FGFR1), is increasingly recognized as a tumor suppressor in different types of cancers. However, little is known on the biological and functional significance of miR-133b/FGFR1 regulation in osteosarcoma. METHODS: The expressions of miR-133b and FGFR1 were examined by RT-qPCR and compared between 30 paired normal bone tissues and OS tissues, and also between normal osteoblasts and three OS cells lines, MG-63, U2OS, and SAOS-2. Using U2OS and MG-63 as the model system, the functional significance of miR-133b and FGFR1 was assessed on cell viability, proliferation, apoptosis, migration/invasion, and epithelial-mesenchymal transition (EMT) by overexpressing miR-133b and down-regulating FGFR1 expression, respectively. Furthermore, the signaling cascades controlled by miR-133b/FGFR1 were examined. RESULTS: miR-133b was significantly down-regulated while FGFR1 robustly up-regulated in OS tissues and OS cell lines, when compared to normal bone tissues and normal osteoblasts, respectively. Low miR-133b expression and high FGFR1 expression were associated with location of the malignant lesion, advanced clinical stage, and distant metastasis. FGFR1 was a direct target of miR-133b. Overexpressing miRNA-133b or knocking down FGFR1 significantly reduced the viability, proliferation, migration/invasion, and EMT, but promoted apoptosis of both MG-63 and U2OS cells. Both the Ras/MAPK and PI3K/Akt intracellular signaling cascades were inhibited in response to overexpressing miRNA-133b or knocking down FGFR1 in OS cells. CONCLUSION: miR-133b, by targeting FGFR1, presents a plethora of tumor suppressor activities in OS cells. Boosting miR-133b expression or reducing FGFR1 expression may benefit OS therapy.

7.
Ying Yong Sheng Tai Xue Bao ; 28(12): 3841-3847, 2017 Dec.
Artículo en Chino | MEDLINE | ID: mdl-29696878

RESUMEN

The distribution characteristics of carbon density under aerially seeded Pinus massoniana plantations in Ganzhou City of Jiangxi Province were studied. Total 15 factors, including site, stand, understory vegetation, litter and so on were selected to establish a relationship model between stand carbon density and influencing factors, and the main influencing factors were also screened. The results showed that the average carbon density was 98.29 t·hm-2 at stand level with soil layer (49.58 t·hm-2) > tree layer (45.25 t·hm-2) > understory vegetation layer (2.23 t·hm-2) > litter layer (1.23 t·hm-2). Significantly positive correlations were found among the tree, litter and soil layers, but not among the other layers. The main factors were tree density, avera-ge diameter at breast height (DBH), soil thickness, slope position, stand age and canopy density to affect carbon density in aerially seeded P. massoniana plantations. The partial correlation coefficients of the six main factors ranged from 0.331 to 0.434 with significance by t test. The multiple correlation coefficient of quantitative model I reached 0.796 with significance by F test (F=9.28). For stand density, the best tree density and canopy density were 1500-2100 plants·hm-2 and 0.4-0.7, respectively. The moderate density was helpful to improve ecosystem carbon sequestration. The carbon density increased with increasing stand age, DBH and soil thickness, and was higher in lower than middle and upper slope positions.


Asunto(s)
Secuestro de Carbono , Carbono , Pinus , China , Ecosistema , Suelo
8.
Ying Yong Sheng Tai Xue Bao ; 26(4): 1071-6, 2015 Apr.
Artículo en Chino | MEDLINE | ID: mdl-26259448

RESUMEN

The relationships between understory vegetation coverage and environmental factors in Pinus massoniana plantations from aerial seeding were studied by using principal component analysis, redundancy analysis and variation partitioning. The selected environmental factors in total explained 74.2% variation of the understory vegetation coverage. At low altitude, stand characteristics were the key factor to influence the understory vegetation coverage. Stand characteristics, soil property and topographic factor were respectively explained 55.0% (including 29.1% for separateness and 25.9% for interaction with other factors), 38. 9% (including 12.1% for separateness and 26.8% for interaction with other factors) and 9.0% (including 5.6% for separateness and 3.4% for interaction with other factors) of the total variation. Average diameter at breast height and canopy density affected mostly and positively correlated with the coverage of bryophyta, graminoid and shurb groups at significant level. Noncapillary porosity and soil water content showed a highly significant positive correlation to dicranopteris coverage, whereas average diameter at breast height, canopy density, soil nutrients and enzyme activity significantly negatively correlated with it. The coverage of graminoid, bryophyta and shurb groups showed the positive correlations, which indicated the three groups could promote each other, while the dicranopteris coverage had significant negative correlation with the three groups mentioned above.


Asunto(s)
Biodiversidad , Bosques , Pinus , Plantas , Suelo , Agua
9.
Ying Yong Sheng Tai Xue Bao ; 18(6): 1388-92, 2007 Jun.
Artículo en Chino | MEDLINE | ID: mdl-17763747

RESUMEN

Taking the natural broadleaf forest in Wuyuan County of Jiangxi Province as study object, a total of 30 representative photos of near-view landscapes and related information were collected. The scenic beauty values were acquired by public judgment method, and the relationship models of scenic beauty values and landscape elements were established by using multiple mathematical model. The results showed that the main elements affecting the near-view landscape quality of natural broadleaf forest were the trunk form, stand density, undergrowth coverage and height, natural pruning, and color richness, with the partial correlation coefficients being 0.4482-0.7724, which were significant or very significant by t-test. The multiple correlation coefficient of the model reached 0.9508, showing very significant by F test (F = 36.11). Straight trunk, better natural pruning and rich color did well, while the super-high or low stand density and undergrowth coverage and height did harm to the scenic beauty. Several management measures for the vertical structure optimization of these landscape elements were put forward.


Asunto(s)
Conservación de los Recursos Naturales/métodos , Ecosistema , Planificación Ambiental , Árboles/crecimiento & desarrollo , Betula/crecimiento & desarrollo , China , Ilex/crecimiento & desarrollo , Modelos Teóricos
10.
Zhong Yao Cai ; 28(12): 1105-7, 2005 Dec.
Artículo en Chino | MEDLINE | ID: mdl-16568670

RESUMEN

OBJECTIVE: To study the optimal extraction process of polysaccharide from Baphicacanthus cuaia (Nees) Bremek. METHODS: The optimal extraction process was selected with uniform design and statistical analysis system (SAS). The content of polysaccharide in the extract was determined to investigate the influence of temperature of extraction, the time of extraction and the solid-liquid ratio on it. RESULTS: The optimal extraction process was extraction temperature 90 degrees C with 2 hours and with 1:50 (g/ml) of Baphicacanthus cuaia (Nees) Bremek weight to distilled water. The optimum extraction rates of Polysaccharide from Baphicacanthus cuaia (Nees) Bremek and Isatis indigotica Fort were 3.26% and 12.76%.


Asunto(s)
Isatis/química , Plantas Medicinales/química , Polisacáridos/aislamiento & purificación , Tecnología Farmacéutica/métodos , Medicamentos Herbarios Chinos/análisis , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/aislamiento & purificación , Isatis/clasificación , Raíces de Plantas/química , Polisacáridos/análisis , Análisis de Regresión , Rizoma/química , Temperatura , Factores de Tiempo
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