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Reviews in Environmental Science and Bio/Technology - The world’s energy system is still dominated by fossil fuels. While there is a rapid reduction in the cost of renewable energy and the...  相似文献   
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Molecular Biology Reports - Plant-derived phytochemicals such as flavonoids have been explored to be powerful antioxidants that protect against oxidative stress-related diseases. In the present...  相似文献   
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Infection of human cells by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) relies on its binding to a specific receptor and subsequent fusion of the viral and host cell membranes. The fusion peptide (FP), a short peptide segment in the spike protein, plays a central role in the initial penetration of the virus into the host cell membrane, followed by the fusion of the two membranes. Here, we use an array of molecular dynamics simulations that take advantage of the highly mobile membrane mimetic model to investigate the interaction of the SARS-CoV2 FP with a lipid bilayer representing mammalian cellular membranes at an atomic level and to characterize the membrane-bound form of the peptide. Six independent systems were generated by changing the initial positioning and orientation of the FP with respect to the membrane, and each system was simulated in five independent replicas, each for 300 ns. In 73% of the simulations, the FP reaches a stable, membrane-bound configuration, in which the peptide deeply penetrated into the membrane. Clustering of the results reveals three major membrane-binding modes (binding modes 1–3), in which binding mode 1 populates over half of the data points. Taking into account the sequence conservation among the viral FPs and the results of mutagenesis studies establishing the role of specific residues in the helical portion of the FP in membrane association, the significant depth of penetration of the whole peptide, and the dense population of the respective cluster, we propose that the most deeply inserted membrane-bound form (binding mode 1) represents more closely the biologically relevant form. Analysis of FP-lipid interactions shows the involvement of specific residues, previously described as the “fusion-active core residues,” in membrane binding. Taken together, the results shed light on a key step involved in SARS-CoV2 infection, with potential implications in designing novel inhibitors.  相似文献   
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Kenaf (Hibiscus cannabinus L.) and roselle (H. sabdariffa L.) are valuable fibre crop species with diverse end use. Phylogenetic relationship of 73 accessions of kenaf, roselle and their wild relatives from 15 countries was assessed using 44 inter-simple sequence repeat (ISSR) and jute (Corchorus olitorius L.) specific simple sequence repeats (SSR) markers. A total of 113 alleles were identified of which 61.95 % were polymorphic. Jute specific SSR markers exhibited high polymorphism and resolving power in kenaf, although ISSR markers exhibited higher resolving power than SSR markers. Number of polymorphic alleles varied from 1 to 5 for ISSR and 1 to 6 for SSR markers. Cultivated species exhibited higher allele polymorphism (57 %) than the wild species (35 %), but the improved cultivars exhibited lower genetic diversity compared to germplasm accessions. Accessions with common genetic lineage and geographical distribution clustered together. Indian kenaf varieties were distinct from cultivars bred in other countries and shared more genetic homology with African accessions. High genetic diversity was observed in the Indian (J = 0.35–0.74) and exotic kenaf germplasm collections (J = 0.38–0.79), suggesting kenaf might have been introduced in India from Africa through Central Asia during early domestication. Genetic similarity-based cluster analysis was in close accordance with taxonomic classification of Hibiscus.  相似文献   
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We investigated whether a climatic change in temperature affected daily food intake in migrating male redheaded buntings. Groups of adult male birds (n = 18) were photoinduced into migratory phenotype under increasing spring daylengths (NDL); as the birds began to exhibit night restlessness, Zugunruhe, these were allocated into groups, either with ambient (NDL, variable daily temperature: maximum – 29–44 °C and minimum – 16–33 °C; for food intake (six birds) and activity recording, six birds) until 2 weeks after they concluded migration or with constant temperature (NDT, 22 ± 1 °C; for food intake (six birds)) conditions. As day length increased March onwards, daily food intake increased (hyperphagia) in NDL and NDT groups. However, hyperphagia was slower in NDT birds as compared to NDL birds, suggesting that altered ambient temperature affects daily food intake in migrating buntings. Another group of 12 birds were held under constant daylengths (12L:12D; EDT and constant temperature 22 ± 1 °C). Although the onset of Zugunruhe was delayed under EDT, the day of onset of Zugunruhe was taken as day 0. Daily food intake and body weight before and during migration of EDT birds were compared with that of NDT and NDL groups. Daily food intake and body weight increased in all migrating birds, but hyperphagia continued post-migration in NDT birds. The study suggests that constantly suboptimal temperature despite increasing daylength, NDT, appeared to affect feeding and body weight of migratory buntings as evident from continued hyperphagia and body weight gain, even after concluding migrating activity.  相似文献   
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Irisin was first identified in muscle cells. We detected irisin immunoreactivity in various organs of the crested porcupine (Hystrix cristata). In the epidermis, irisin immunoreactivity was localized mainly in stratum basale, stratum spinosum and stratum granulosum layers; immunoreactivity was not observed in the stratum corneum. In the dermis, irisin was found in the external and internal root sheath, cortex and medulla of hair follicles, and in sebaceous glands. Irisin immunoreactivity was found in the neural retina and skeletal muscle fibers associated with the eye. The pineal and thyroid glands also exhibited irisin immunoreactivity.  相似文献   
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