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1.
Foods ; 8(11)2019 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-31694278

RESUMEN

The aim of this study was to develop and validate an improved, simple, and sensitive method for the simultaneous determination of seven types (cadaverine, CAD; hexylamine, HEX; histamine, HIS; phenylethylamine, PEA; putrescine, PUT; tyramine, TYR) of biogenic amines (BAs) in wine matrices. For this reason, a modified QuEChERS combined with ultra-performance liquid chromatography coupled to a triple quadrupole mass spectrometry (UHPLC-QqQ-MS/MS) method was investigated. The optimization of UHPLC-QqQ-MS/MS separation and QuEChERS procedure was performed. Under optimum conditions, the excellent chromatographic performance of the whole separation was accomplished within 6.3 min analyzing time. Meanwhile, the recoveries ranged from 77.2% to 101.7%, while relative standard deviation (RSD) remained between 0.0% and 9.4%. The limit of detection (LOD, 0.50-1.00 µg/L) and the limit of quantification (LOQ, 1.65-3.30 µg/L) were lower than those permitted by legislation in food matrices, which demonstrated the high sensitivity and applicability of this efficient method. This validated method was also applied in a pilot study to analyze BAs in 81 wine samples from Hexi Corridor Region (Gansu Province, Northwest China), CAD, HEX, HIS, PEA, PUT, and TYR were detected to varying degrees in the samples. However, when compared with the existing standards, the BAs in all 81 wine samples did not exceed the prescribed limit value or toxic dose (2-40 mg/L). Moreover, a statistical approach was also conducted using Pearson correlation analysis, and to evaluate their concentrations in terms of wine parameters (storage time, grape variety, wine type, and basic physicochemical index). The results showed that, among the seven kinds of BAs, the concentration of HIS had a certain correlation with alcoholic degree and grape variety. In addition, the level of PEA had a certain correlation with the wine pH and wine storage time. It is worth noting that this seems to be the first report regarding the application of QuEChERS-UHPLC-QqQ-MS/MS in the analysis of BAs in wine in this region.

2.
Appl Plant Sci ; 5(4)2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28439477

RESUMEN

PREMISE OF THE STUDY: Stipa breviflora (Poaceae) is one of the dominant species of the desert steppe in the eastern Eurasian grasslands. Simple sequence repeat (SSR) markers were developed for use in genetic diversity studies of this species. METHODS AND RESULTS: A total of 1954 potentially polymorphic loci were obtained by comparing transcriptome data of eight different S. breviflora individuals. We selected 81 loci to verify polymorphism and 63 loci amplified, of which 21 loci exhibited polymorphism. The number of alleles per locus varied from two to 24, the observed heterozygosity ranged from 0.083 to 0.958, and the expected heterozygosity ranged from 0.396 to 0.738. CONCLUSIONS: These newly identified SSR loci can be used for population genetic and landscape genetic studies of S. breviflora. In addition, 14 loci also amplified in six related Stipa species (S. grandis, S. krylovii, S. bungeana, S. aliena, S. gobica, and S. purpurea).

3.
Ying Yong Sheng Tai Xue Bao ; 25(1): 1-11, 2014 Jan.
Artículo en Chino | MEDLINE | ID: mdl-24765835

RESUMEN

Sustainability is the theme of our time and also the grandest challenge to humanity. Since the 1970s, the term, sustainable development, has frequently appeared in the scientific literature, governmental documents, media promotions for public goods, and commercial advertisements. However, the science that provides the theoretical foundation and practical guidance for sustainable development--sustainability science--only began to emerge in the beginning of the 21st century. Nevertheless, the field has rapidly developed in depth and expanded in scope during the past decade, with its core concepts and research methods coalescing. China, as the most populous country in the world and home to the philosophical root of sustainability science-the unity of man and nature, is obligated to take upon the challenge of our time, to facilitate global sustainability while pursuing the Chinese Dream, and to play a leading role in the development of sustainability science. Toward this grandiose goal, this paper presents the first Chinese introduction to sustainability science, which discusses its basic concepts, research questions, and future directions. Sustainability science is the study of the dynamic relationship between humans and the environment, particularly focusing on the vulnerability, robustness, resilience, and stability of the coupled human-environment system. It is a transdisciplinary science that integrates natural sciences with humanities and social sciences. It hinges on the environment-economy-society nexus, and merges basic and applied research. The key components of sustainability often change with time, place, and culture, and thus sustainability science needs to emphasize multi-scale studies in space and time, with emphasis on landscapes and regions over a horizon of 50 to 100 years. It needs to focus on the relationship between ecosystem services and human well-being, as influenced by biodiversity and ecosystem processes as well as climate change, land use change, and other socioeconomic drivers. Landscape sustainability is at the core of sustainability science, and is expected to be a hot research topic in the next few decades.


Asunto(s)
Conservación de los Recursos Naturales , China , Cambio Climático , Ecosistema , Ambiente , Humanos
4.
Ying Yong Sheng Tai Xue Bao ; 19(9): 2009-15, 2008 Sep.
Artículo en Chino | MEDLINE | ID: mdl-19102317

RESUMEN

Based on the RS image of Longitudinal Range-Gorge Region (LRGR) in 2001, the study area was classified into seven first-class landscape types (forestland, grassland, farmland, wetland, water body, urban land, and glacier), and 26 second-class landscape types in consideration of climate belt, vegetation, and topography. By using GIS technology, the services value of different landscape types of LRGR were studied in regards to the study results on services value of Chinese terrestrial ecosystems. The results indicated that the total services value of LRGR was 5 302.35 x 10(8) yuan x a(-1), accounting for 9.47% of the whole country. The service value of soil conservation was the highest, which occupied 18.05% of the total services value, while the service values of gas adjustability and biodiversity protection ranked the second and third. Due to its distribution extent and services intensity per unit area, the forest landscape, which covered 66.11% of the total area, contributed most (85.34%) to the total service value of LRGR, followed by grassland and farmland landscapes.


Asunto(s)
Conservación de los Recursos Naturales/estadística & datos numéricos , Productos Agrícolas/crecimiento & desarrollo , Ecosistema , Poaceae/crecimiento & desarrollo , Árboles/crecimiento & desarrollo , China , Conservación de los Recursos Naturales/métodos , Sistemas de Información Geográfica , Reproducibilidad de los Resultados , Comunicaciones por Satélite
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