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The Middle Palaeolithic site of Payre in southeastern France yields abundant archaeological material associated with fossil hominid remains. With its long sequence of Middle Pleistocene deposits, Payre is a key site to study the Middle Palaeolithic chronology of this region. This study is the first to investigate carbon and oxygen isotope contents of Neanderthal tooth enamel bioapatite, together with a wide range of herbivorous and carnivorous species. The aim is to contribute to the understanding of hunting behaviour, resource partitioning, diet and habitat use of animals and Neanderthals through a palaeoecological reconstruction.  相似文献   

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Over the last decade, adherent MDCK (Madin Darby canine kidney) and Vero cells have attracted considerable attention for production of cell culture-derived influenza vaccines. While numerous publications deal with the design and the optimization of corresponding upstream processes, one-to-one comparisons of these cell lines under comparable cultivation conditions have largely been neglected. Therefore, a direct comparison of influenza virus production with adherent MDCK and Vero cells in T-flasks, roller bottles, and lab-scale bioreactors was performed in this study. First, virus seeds had to be adapted to Vero cells by multiple passages. Glycan analysis of the hemagglutinin (HA) protein showed that for influenza A/PR/8/34 H1N1, three passages were sufficient to achieve a stable new N-glycan fingerprint, higher yields, and a faster increase to maximum HA titers. Compared to MDCK cells, virus production in serum-free medium with Vero cells was highly sensitive to trypsin concentration. Virus stability at 37 °C for different virus strains showed differences depending on medium, virus strain, and cell line. After careful adjustment of corresponding parameters, comparable productivity was obtained with both host cell lines in small-scale cultivation systems. However, using these cultivation conditions in lab-scale bioreactors (stirred tank, wave bioreactor) resulted in lower productivities for Vero cells.  相似文献   

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Among several candidate perennial taxa, Miscanthus × giganteus has been evaluated and promoted as a promising bioenergy crop. Owing to several limitations, however, of the sterile hybrid, both at the taxon and agronomic production levels, other options need to be explored to not only improve M . × giganteus , which was originally collected in Japan, but to also consider the development of other members of its genus, including Miscanthus sinensis , as bioenergy crops. Indeed, there is likely much to be learned and applied to Miscanthus as a bioenergy crop from the long history of intensive interaction between humans and M. sinensis in Japan, which in some regions of the country spans several thousand years. Combined with its high amount of genetic variation, stress tolerance, biotic interactions with fauna, and function as a keystone species in diverse grasslands and other ecosystems within its native range, the unique and extensive management of M. sinensis in Japan as a forage grass and building material provides agronomists, agroecologists, and plant breeders with the capability of better understanding this species in terms of potential contribution to bioenergy crop development. Moreover, the studies described in this review may serve as a platform for future research of Miscanthus as a bioenergy crop in other parts of the world.  相似文献   

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Traditional techniques for stable isotope analysis (SIA) generally require sacrificing animals to collect tissue samples; this can be problematic when studying diets of endangered species such as the pallid sturgeon Scaphirhynchus albus. Our objectives were to (i) determine if pectoral fin tissue (non‐lethal) could be a substitute for muscle tissue (lethal) in SIA of juvenile pallid sturgeon, and (ii) evaluate the influence of preservation techniques on stable isotope values. In the laboratory, individual juvenile pallid sturgeon were held for up to 186 day and fed chironomids, fish, or a commercially available pellet diet. Significant, positive relationships (r² ≥ 0.8) were observed between fin and muscle tissues for both δ15N and δ13C; in all samples isotopes were enriched in fins compared to muscle tissue. Chironomid and fish based diets of juvenile pallid sturgeon were distinguishable for fast growing fish (0.3 mm day?1) using stable δ15N and δ13C isotopes. Frozen and preserved fin tissue δ15N isotopes were strongly related (r2 = 0.89) but δ13C isotopes were weakly related (r2 = 0.16). Therefore, freezing is recommended for preservation of fin clips to avoid the confounding effect of enrichment by ethanol. This study demonstrates the utility of a non‐lethal technique to assess time integrated food habits of juvenile pallid sturgeon and should be applicable to other threatened or endangered species.  相似文献   

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The free energies of solvation of six nucleic acid bases (adenine, cytosine, hypoxanthine, guanine, thymine, and uracil) in water and chloroform are calculated using CM2 class IV charges and SM5.42R atomic surface tensions. Using any of three approximations to the electronic wave function (AM1, Hartree-Fock, or DFT), we obtain good agreement with experiment for five cases where the experimental results are known for the partition coefficients between the two solvents. Decomposition of the solvation effects into bulk electrostatic contributions and first-solvation-shell effects shows that the partitioning is dominated by the former, and this illustrates the importance of using accurate partial atomic charges for modeling these molecules in aqueous solution.  相似文献   

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Few studies have examined exodermal development in relation to the formation of barriers to both radial oxygen loss (ROL) and solute penetration along growing roots. Here, we report on the structural development, chemical composition and functional properties of the exodermis in two diverse wetland grasses, Glyceria maxima and Phragmites australis. Anatomical features, development, the biochemical composition of exodermal suberin and the penetration of apoplastic tracers and oxygen were examined. Striking interspecific differences in exodermal structure, suberin composition and quantity per unit surface area, and developmental changes along the roots were recorded. Towards the root base, ROL and periodic acid (H(5)IO(6)) penetration were virtually stopped in P. australis; in G. maxima, a tight ROL barrier restricted but did not stop H(5)IO(6) penetration and the exodermis failed to stain with lipidic dyes. Cultivation in stagnant deep hypoxia conditions or oxygenated circulating solution affected the longitudinal pattern of ROL profiles in G. maxima but statistically significant changes in exodermal suberin composition or content were not detected. Interspecific differences in barrier performance were found to be related to hypodermal structure and probably to qualitative as well as quantitative variations in suberin composition and distribution within exodermal cell walls. Implications for root system function are discussed, and it is emphasized that sufficient spatial resolution to identify the effects of developmental changes along roots is crucial for realistic evaluation of exodermal barrier properties.  相似文献   

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Type 2 diabetes is one of the biggest health challenges in the world and WHO projects it to be the 7th leading cause of death in 2030. It is a chronic condition affecting the way our body metabolizes sugar. Insulin resistance is high risk factor marked by expression of Lipoprotein Lipases and Peroxisome Proliferator-Activated Receptor that predisposes to type 2 diabetes. AMP-dependent protein kinase in AMPK signaling pathway is a central sensor of energy status. Deregulation of AMPK signaling leads to inflammation, oxidative stress, and deactivation of autophagy which are implicated in pathogenesis of insulin resistance. SIRT4 protein deactivates AMPK as well as directly inhibits insulin secretion. SIRT4 overexpression leads to dyslipidimeia, decreased fatty acid oxidation, and lipogenesis which are the characteristic features of insulin resistance promoting type 2 diabetes. This makes SIRT4 a novel therapeutic target to control type 2 diabetes. Virtual screening and molecular docking studies were performed to obtain potential ligands. To further optimize the geometry of protein–ligand complexes Quantum Polarized Ligand Docking was performed. Binding Free Energy was calculated for the top three ligand molecules. In view of exploring the stereoelectronic features of the ligand, density functional theory approach was implemented at B3LYP/6-31G* level. 30 ns MD simulation studies of the protein–ligand complexes were done. The present research work proposes ZINC12421989 as potential inhibitor of SIRT4 with docking score (?7.54 kcal/mol), docking energy (?51.34 kcal/mol), binding free energy (?70.21 kcal/mol), and comparatively low energy gap (?0.1786 eV) for HOMO and LUMO indicating reactivity of the lead molecule.  相似文献   

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This study examined larval food habits of two syntopic, related, carabids Amara chalcites Dejean and A. congrua Morawitz using a laboratory-rearing experiment, and the results were compared with those of a previous stable-isotope analyses of the same species. Larvae were reared on six different diets (seeds of Capsella bursa-pastoris (Linnaeus) Medikus, Stellaria media (Linnaeus) Villars, Taraxacum officinale Weber ex Wiggers; mixed seeds; Tenebrio molitor Linnaeus larvae; and Tenebrio larvae + mixed seeds). For both species, beetles fed seed diets exhibited moderate to high survival rates, with the exception of those fed Stellaria seeds, on which A. congrua showed low survival rates. The pure-animal diet resulted in high survival rates of A. chalcites but low survival rates of A. congrua. These results were consistent with those of the isotope analysis, in which A. chalcites larvae were more carnivorous than were A. congrua larvae, and the larvae of the two species appeared to prefer different types of seeds. In contrast, the effect of diet on adult weight differed between the two methods. In the laboratory experiments, supplementing seeds with animal food during the larval stage positively affected adult weight for both species, whereas in the isotope analysis, the positive effect only occurred in A. chalcites. Possible explanations for the discrepancy between the two methods and suggestions for future research are provided.  相似文献   

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