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Hydroboration of 5 alpha-cholest-8-ene, 5 alpha,14 beta-cholest-8-ene and 5 alpha,14 beta-cholest-7-ene provides a simple route to oxygenated steroids with 14 beta- and 8 alpha,14 beta- unnatural stereochemistry. 相似文献
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A C-glucoside of cholic acid was synthesized by the introduction of an acetyl group at position 3 alpha and direct one-pot C-glucosidation using 2,3,4,6-tetra-O-benzyl-alpha-D-glucopyranosyl chloride. 相似文献
5.
Anastasia Klimova Ricardo Rodríguez-Estrella Guanliang Meng Jesús Neftalí Gutiérrez-Rivera María Luisa Jimenez-Jimenez Shanlin Liu 《Diversity & distributions》2023,29(3):438-461
Aim
Desert springs or oases are the only permanent mesic environments in highly water-limited arid regions. Oases have immense cultural, evolutionary and ecological importance for people and a high number of endemic and relic species. Nevertheless, they are also highly vulnerable ecosystems, with invasive species, overexploitation and climate change being the primary threats. We used the arthropod communities' spatiotemporal diversity and distribution patterns as a proxy to understand biodiversity dynamics in two geographically close but ecologically contrasting and highly threatened ecosystems: deserts and oases.Location
Baja California Peninsula, Mexico.Methods
Arthropod communities at five oases and surrounding desert scrub areas were sampled in two seasons. Using DNA metabarcoding and traditional taxonomic surveys, we tried to identify what biotic and abiotic characteristics of the habitat are important drivers of arthropod diversity and how these characteristics can change across spatial and temporal scales.Results
Over 6200 individuals representing 23 orders were collected. In oasis samples, the community composition fluctuated more in space (i.e. among sites) than in time (i.e. seasons). Thus, seasonal changes did not affect oasis community diversity and composition, but the dissimilarity among sites increased with geographic distance. Moreover, anthropic activities negatively correlated with arthropod diversity in oases. On the other hand, the season, geography (e.g. latitude) and biotic characteristics of the habitat (e.g. sampled scrub species) significantly affected the diversity and composition of the desert arthropod communities.Main Conclusions
Neutral dynamics (e.g. historical climatic events, dispersal limitation and spatial component) and human impact significantly influenced the biodiversity patterns of each oasis. In contrast, the habitat's seasonal variation and biotic characteristics were the most important variables influencing the diversity of the desert communities. Baja California oases harbour distinct invertebrate communities; therefore, each oasis should be conserved individually to preserve these unique assemblages. 相似文献6.
Kitashova Anastasia Schneider Katja Fürtauer Lisa Schröder Laura Scheibenbogen Tim Fürtauer Siegfried Nägele Thomas 《Photosynthesis research》2021,147(1):49-60
Photosynthesis Research - Photosynthesis and carbohydrate metabolism of higher plants need to be tightly regulated to prevent tissue damage during environmental changes. The intracellular position... 相似文献
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Daisylyn Senna Tan Yanpu Chen Ya Gao Anastasia Bednarz Yuanjie Wei Vikas Malik Derek Hoi-Hang Ho Mingxi Weng Sik Yin Ho Yogesh Srivastava Sergiy Velychko Xiaoxiao Yang Ligang Fan Johnny Kim Johannes Graumann Gary D. Stormo Thomas Braun Jian Yan Hans R. Schler Ralf Jauch 《Molecular biology and evolution》2021,38(7):2854
8.
Sukhorukov Vladimir S. Mudzhiri Natalia M. Voronkova Anastasia S. Baranich Tatiana I. Glinkina Valeria V. Illarioshkin Sergey N. 《Biochemistry. Biokhimii?a》2021,86(6):667-679
Biochemistry (Moscow) - Alzheimer’s disease is the most common age-related neurodegenerative disease. Understanding of its etiology and pathogenesis is constantly expanding. Thus, the... 相似文献
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Ovsiannikova Natalia L. Lavrushkina Svetlana V. Ivanova Anastasia V. Mazina Ludmila M. Zhironkina Oxana A. Kireev Igor I. 《Biochemistry. Biokhimii?a》2021,86(10):1288-1300
Biochemistry (Moscow) - One of the main factors associated with worse prognosis in oncology is metastasis, which is based on the ability of tumor cells to migrate from the primary source and to... 相似文献
10.
Reavis Zackery W. Mirjankar Nikhil Sarangi Srikant Boyle Stephen H. Kuhn Cynthia M. Matson Wayne R. Babyak Michael A. Matson Samantha A. Siegler Ilene C. Kaddurah‑Daouk Rima Suarez Edward C. Williams Redford B. Grichnik Katherine Stafford‑Smith Mark Georgiades Anastasia 《Metabolomics : Official journal of the Metabolomic Society》2021,17(6):1-13
Metabolomics - Metabolomics applications to the aquaculture research are increasing steadily. The use of standardized proton nuclear magnetic resonance (1H NMR) spectroscopy can provide the... 相似文献