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1.
Sci Total Environ ; 905: 167084, 2023 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-37734603

RESUMEN

Cropland encroachment on protected areas causes natural habitat loss, which may damage ecosystem functions and biodiversity conservation, leading to trade-offs between crop production and habitat conservation. Here we investigate the sustainable utilization and effects of cropland within protected areas, on which we make trade-offs with an established framework. Analyses show that 3.08 million hectares of cropland are identified within protected areas, about two-thirds less sustainable or less beneficial. 41 % and 26 % are expected to be retired for inferior sustainability and effects under the strictest and laxest habitat protection scenario, respectively. Although these retirements would cause a loss of crop benefits of 0.3-0.7 billion US dollars, they could bring ecological benefits of 2.9-3.6 billion US dollars annually. Approximately 11 % of cropland within protected areas is identified in poor agricultural conditions, and 19 % occupies areas of high protection importance, both of which are recommended for priority retirement. This study reveals the characteristics and impacts of cropland in protected areas and provides a quantified trade-off approach for conflicts between cropland and natural habitats, with important implications for production, conservation, and their trade-offs.


Asunto(s)
Ecosistema , Jubilación , Conservación de los Recursos Naturales , Biodiversidad , China , Productos Agrícolas
2.
Sci Data ; 10(1): 321, 2023 05 26.
Artículo en Inglés | MEDLINE | ID: mdl-37236983

RESUMEN

Understanding the spatiotemporal dynamics of global 3D urban expansion over time is becoming increasingly crucial for achieving long-term development goals. In this study, we generated a global dataset of annual urban 3D expansion (1990-2010) using World Settlement Footprint 2015 data, GAIA data, and ALOS AW3D30 data with a three-step technical framework: (1) extracting the global constructed land to generate the research area, (2) neighborhood analysis to calculate the original normalized DSM and slope height of each pixel in the study area, and (3) slope correction for areas with a slope greater than 10° to improve the accuracy of estimated building heights. The cross-validation results indicate that our dataset is reliable in the United States(R2 = 0.821), Europe(R2 = 0.863), China(R2 = 0.796), and across the world(R2 = 0.811). As we know, this is the first 30-meter 3D urban expansion dataset across the globe, which can give unique information to understand and address the implications of urbanization on food security, biodiversity, climate change, and public well-being and health.

3.
Environ Sci Pollut Res Int ; 30(2): 2685-2702, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35931854

RESUMEN

Farmland abandonment, a widespread phenomenon during land-use transition, leads to a cycling or vanishing evolution of farmland resources. As urbanization advances, an increasing number of agricultural laborers migrate from rural to urban areas, causing ongoing farmland abandonment. However, in contrast to the abandoned information extraction and driving mechanisms revelation, the potential risk of farmland abandonment has received insufficient attention. This study took Yangtze River Economic Belt of China as study area, selected multiple aspects to construct a risk assessment system for farmland abandonment, and applied time series change detection to verify the results. The results showed that (1) farmland abandonment risk, with a regional average value of 0.0978, has strong spatial heterogeneity, with high values clustering in Yunnan-Guizhou and Sichuan-Chongqing mountainous areas and low values distributed in the midstream and downstream plains and the Sichuan Basin. (2) The proportion of farmland area gradually decreased as the risk grade increased. Farmland, with low abandonment risk, occupied an area of 204,837 km2, constituting the highest percentage of 35.18% among the overall farmland, and was mainly distributed in the provinces of Jiangsu and Anhui. The area of farmland with high risk was 16,458 km2, only accounting for 2.83%, the majority of which was clustered in Sichuan and Yunnan provinces. (3) The Normalized Difference Vegetation Index (NDVI) time series change detection validated the reliability of the risk assessment system. Samples of farmland having low abandonment risk indeed had the lowest abandonment rate of 10%, and those which indicated high risk had the highest abandonment rate of 32%. We propose differentiated managements for farmland resources with high and low abandonment risk from the perspective of sustainable use. This study provides a more reasonable and scientific system for farmland abandonment risk assessment and helps to fill the research gap.


Asunto(s)
Granjas , China , Reproducibilidad de los Resultados , Factores de Tiempo , Medición de Riesgo
4.
Comput Math Methods Med ; 2022: 1515810, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35912141

RESUMEN

Cervical cancer is one of the main causes of cancer death all over the world. Most diseases such as cervical epithelial atypical hyperplasia and invasive cervical cancer are closely related to the continuous infection of high-risk types of human papillomavirus. Therefore, the high-risk types of human papillomavirus are the key to the prevention and treatment of cervical cancer. With the accumulation of high-throughput and clinical data, the use of systematic and quantitative methods for mathematical modeling and computational prediction has become more and more important. This paper summarizes the mathematical models and prediction methods of the risk types of human papillomavirus, especially around the key steps such as feature extraction, feature selection, and prediction algorithms. We summarized and discussed the advantages and disadvantages of existing algorithms, which provides a theoretical basis for follow-up research.


Asunto(s)
Alphapapillomavirus , Infecciones por Papillomavirus , Neoplasias del Cuello Uterino , Femenino , Humanos , Modelos Teóricos , Papillomaviridae
5.
Oncol Lett ; 24(2): 249, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35761944

RESUMEN

Despite the advancement in the diagnosis and therapeutic strategies for colorectal cancer, the outcomes of patients with colorectal cancer remain unsatisfactory. Alisol A is a natural constituent of Alismatis rhizoma (zexie) and has demonstrated anti-cancer properties; however, the function of Alisol A in colorectal cancer is still unknown. In the present study, the effect of Alisol A on colorectal cancer progression was investigated. MTT and colony formation assays showed that treatment with Alisol A repressed colorectal cancer cell proliferation in a dose-dependent manner. Similarly, western blot analysis demonstrated that Alisol A upregulated E-cadherin protein expression levels, but downregulated N-cadherin and Vimentin protein expression levels in colorectal cancer cells. In addition, the number of cells in G0/G1 phase was enhanced, while that of S phase was reduced in Alisol A-treated colorectal cancer cells. Apoptosis and pyroptosis of colorectal cancer cells were stimulated following treatment with Alisol A. Alisol A suppressed the migration ability of colorectal cancer cells in a dose-dependent manner. Moreover, Alisol A increased the chemotherapeutic sensitivity of colorectal cancer cells to cisplatin. Mechanically, western blot analysis confirmed that Alisol A repressed the phosphorylation levels of PI3K, Akt and mTOR in colorectal cancer cells. The Akt activator, SC79 reversed the effect of Alisol A on colorectal cancer cell proliferation and apoptosis. In conclusion, Alisol A induced an inhibitory effect on colorectal cancer progression by inactivating PI3K/Akt signaling.

6.
Sci Total Environ ; 806(Pt 3): 151287, 2022 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-34736756

RESUMEN

Catalytic fast pyrolysis experiments of low-density polyethylene (LDPE) over HZSM-5 were carried out by using infrared heating technology. The effects of heating rate (1-30 °C/s), pyrolysis temperature (450-650 °C), and mass ratio of catalyst to LDPE (0:100 to 50:100) on product distribution and oil composition in LDPE pyrolysis were investigated, and the fast pyrolysis mechanism was explored. The results indicated that a higher heating rate, namely 20 °C/s, can remarkably enhance the liquid oil yield (93.42%), but the oil is heavy due to about 90% high­carbon n-aliphatics. The addition of HZSM-5 performed an excellent effect on obtaining high-quality liquid oils, among which the total content of monocyclic aromatic hydrocarbons (MAHs) and iso-aliphatics obviously increase from 0.68% to 70.26%. The optimal HZSM-5/LDPE ratio of 10:100 was identified by considering the cost-effective factor. Furthermore, the lower catalytic temperature is favorable to the generation of light oil components, especially MAHs. The feasible generation paths were proposed, which mainly derived from the secondary reaction of the intermediate formed by initial chain cleavage including cyclization, aromatization, Diels-Alder reaction, as well as isomerization.


Asunto(s)
Polietileno , Pirólisis , Biocombustibles , Catálisis , Calefacción , Calor
7.
J Med Syst ; 40(6): 135, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27098778

RESUMEN

Because of the complex and fine structure, visualization of the heart still remains a challenging task, which makes it an active research topic. In this paper, we present a visualization system for medical data, which takes advantage of the recent graphics processing unit (GPU) and can provide real-time cardiac visualization. This work focuses on investigating the anatomical structure visualization of the human heart, which is fundamental to the cardiac visualization, medical training and diagnosis assistance. Several state-of-the-art cardiac visualization methods are integrated into the proposed system and a task specified visualization method is proposed. In addition, auxiliary tools are provided to generate user specified visualization results. The contributions of our work lie in two-fold: for doctors and medical staff, the system can provide task specified visualization with interactive visualization tools; for researchers, the proposed platform can serve as a baseline for comparing different rendering methods and can easily incorporate new rendering methods. Experimental results show that the proposed system can provide favorable cardiac visualization results in terms of both effectiveness and efficiency.


Asunto(s)
Corazón/anatomía & histología , Procesamiento de Imagen Asistido por Computador/métodos , Imagenología Tridimensional/métodos , Gráficos por Computador , Humanos
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