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971.
Valentina Adami Natalie Homer Nadine Utz Saskia Lippens Joshua Z. Rappoport Julia Fernandez-Rodriguez 《Journal of biomolecular techniques》2021,32(1):1
Core facilities (CFs) provide a centralised access to costly equipment, scientific expertise, experimental design, day-to-day technical support and training of users. CFs have a tremendous impact on research outputs, skills and educational agendas, increasing the competencies of staff, researchers and students. However, the rapid development of new technologies and methodologies for the life sciences requires fast adaptation and development of existing core facilities and their technical and scientific staff. Given the scarcity of well-defined CF career paths, CF staff positions are typically filled by people having followed either academic or technical tracks. Each academic institution follows different policies and often fails to adequately recognize the merits of CF personnel and to support their training efficiently. Thus, the Core Technologies for Life Science association (CTLS), through the Training working group, has conducted an anonymous online survey to assess the training needs of CF personnel, as well as to identify common characteristics and challenges in this relatively new and dynamic career type. 275 individuals, including core managers and directors, technicians, technologists and administrators, participated in the survey. The survey was divided into 2 sections; the first, applied to all respondents, and the second, specifically targeted core management issues. Training needs in technological areas, financial and soft skills, management and administrative issues were surveyed as well. The lack of clarity and consistency regarding established career paths for CF professionals was evident from the second part of the survey, highlighting geographical or cultural differences. Gender balance was achieved and the distribution was always taken into account. The results of this survey highlight a need to develop better training resources for CF staff, to improve their recognition within academic institutions, and to establish a recognized career pathway. 相似文献
972.
973.
The binding of a tetrapeptide lysyltryptophylglycyllysine to nucleosome core particles has been investigated using UV absorption and fluorescence spectroscopy. Modifications of the absorption spectra and fluorescence quenching of the tryptophyl residue are consistent with stacking between the indole ring and nucleic acid bases. Therefore DNA interactions with histones do not prevent stacking of the tryptophyl residue with nucleic acid bases in the peptide-core particle complexes. The number of peptide binding sites is reduced to half that of naked DNA. 相似文献
974.
Six polyacetylenes have been isolated from immature seeds of safflower (Carthamus tinctorius L.) by thin-layer chromatography. They were identified as 1,11-tridecadiene-3,5,7,9-tetrayne, 1,3,11-tridecatriene-5,7,9-triyne, 1,3,5,11-tridecatetraene-7,9-diyne, 1-tridecene-3,5,7,9,11-pentayne, 1,3-tridecadiene-5,7,9,11-tetrayne and 1,3,5-tridecatriene-7,9,11-triyne from the results of their spectroscopic and chemical analyses. Three of these polyacetylenes had not been isolated from Carthamus tinctorius L.Changes in the polyacetylene content during maturation were followed by the measurement of ultraviolet absorbance. While 1,3,11-tridecatriene-5,7,9-triyne and 1,3,5,11-tridecatetraene-7,9-diyne had already occurred abundantly at the day of flowering, the amounts of the other polyacetylenes reached the maximum values at the fourth to sixth days after flowering. Although the total amounts of the six polyacetylenes were about 0.8 mmole/g lipid at the fourth day after flowering, no polyacetylene was detected in the mature seeds. 相似文献
975.
Shuichi Horie Hidemi Ishii Hiroyuki Nakazawa Tetsuya Suga Hirotake Orii 《Biochimica et Biophysica Acta (BBA)/General Subjects》1979,585(3):435-443
The cross-points of rat liver peroxisomes, peroxisomal core and the core components were determined by means of cross-partition in two phase systems. The partitions were carried out in the systems containing 6% (w/w) Dextran T 500 and 6% (w/w) polyethyleneglycol 4000 in sodium salts. The same crosspoint, pH 5.6, was obtained in peroxisomal marker enzymes in light mitochondrial fraction of liver homogenate, such as catalase, d-amino acid oxidase and urate oxidase. The cross-point as determined by cross-partition of purified peroxisomal core was 6.7. The cross-points of urate oxidase and framework protein fractions obtained by alkali treatment on the purified core were 7.8 and 4.2, respectively, and the ratio of the proteins of urate oxidase to framework protein was 2:1. The theoretical value of cross-point of the core calculated from the relationship between the cross-point and protein ratio of each component of the core coincided with the experimental value obtained by this method. 相似文献
976.
Human fibroblast interferon (Hu IFN beta) was directly introduced with glass micropipets into the cytoplasm of Hela cells. Such an injection of more than 10(4) molecules per cell failed to induce any antiviral state when challenged with vesicular stomatitis virus (VSV). These findings are discussed in relation to the possible role of internalization in the mechanism of antiviral action of interferon. 相似文献
977.
978.
Robert J Woods 《Glycoconjugate journal》1998,15(3):209-216
Computational methods have had a long history of application to carbohydrate systems and their development in this regard is discussed. The conformational analysis of carbohydrates differs in several ways from that of other biomolecules. Many glycans appear to exhibit numerous conformations coexisting in solution at room temperature and a conformational analysis of a carbohydrate must address both spatial and temporal properties. When solution nuclear magnetic resonance data are used for comparison, the simulation must give rise to ensemble-averaged properties. In contrast, when comparing to experimental data obtained from crystal structures a simulation of a crystal lattice, rather than of an isolated molecule, is appropriate. Molecular dynamics simulations are well suited for such condensed phase modeling. Interactions between carbohydrates and other biological macromolecules are also amenable to computational approaches. Having obtained a three-dimensional structure of the receptor protein, it is possible to model with accuracy the conformation of the carbohydrate in the complex. An example of the application of free energy perturbation simulations to the prediction of carbohydrate-protein binding energies is presented. 相似文献