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91.
Bioanalytical automation expanded at Glaxo Inc. from 1987 to
1991 by cycling through periods of justification, planning,
implementation, obstacle-jumping and success, which justified
continued cycling. In 1990 it became evident that the technology and
its growth needed to be planned and the resources had to be
managed. A Strategic Plan was researched and prepared. The plan
describes the mission, values, goals and structure of the Bioanalytical
Automation Group and the most important requirements for
achieving those planned goals, including: (1) Long-term management
commitment; (2) Trained, dedicated personnel; (3) Quality
facilities; (4) Teamwork; and (5) Investment in automationcompatible
equipment. The strategic plan has been in effect for over
a year; current status, history, and the future are discussed in this article. 相似文献
92.
Fatty acid analysis of blood serum, seminal plasma, and spermatozoa of normozoospermic vs. Asthernozoospermic males 总被引:2,自引:0,他引:2
Docosahexaenoic acid (DHA; 22∶6n−3) is found in extremely high levels in human ejaculate with the majority occurring in the spermatozoa. However, the relative concentration of DHA and other fatty acids, in blood serum, seminal plasma, and spermatozoa of asthenozoospermic vs. normozoospermic individuals is not known. We analyzed the phospholipid fatty acid composition of blood serum, seminal plasma, and spermatozoa of normozoospermic men and asthenozoospermic men in order to determine if DHA levels, as well as the levels of other fatty acids, differed. The serum phospholipid DHA levels were similar in the two groups, suggesting similar intakes of dietary DHA. On the other hand, seminal plasma levels of DHA (3.0 vs. 3.7%) and total polyunsaturated fatty acids (PUFA) (11.8 vs. 13.5%) were significantly lower in asthenozoospermic vs. normozoospermic men, respectively, while 18∶1 (19.0 vs. 16.8%) and monounsaturated fatty acids (MUFA) (24.2 vs. 21.7%) were significantly higher in the asthenozoospermic vs. the normozoospermic men. Spermatozoa from asthenozoospermic men had higher levels of 18∶1, 20∶0, 22∶0, 22∶1, and 24∶0 than sperm from normozoospermic men, and lower levels of 18∶0 and DHA (8.2 vs. 13.8%). Furthermore, total MUFA (19.3 vs. 16.5%) was higher and total PUFA (19.0 vs. 24.0%), n−3 fatty acids (9.3 vs. 14.6%), and the ratio of n−3 to n−6 fatty acids (1.0 vs. 1.6) were lower in the asthenozoospermic men. Therefore, in asthenozoospermic individuals, lower levels of DHA in the seminal plasma, but not in the blood serum, mimic the decreased concentrations of DHA in the spermatozoa. This suggests that the lower concentrations of spermatozoon DHA in these individuals are due not to dietary differences but to some type of metabolic difference in the asthenozoopermic men. 相似文献
93.
John A. Robertson Jean Théberge Julie Weller Dick J. Drost Frank S. Prato Alex W. Thomas 《Journal of the Royal Society Interface》2010,7(44):467-473
Extremely low-frequency magnetic fields (from DC to 300 Hz) have been shown to affect pain sensitivity in snails, rodents and humans. Here, a functional magnetic resonance imaging study demonstrates how the neuromodulation effect of these magnetic fields influences the processing of acute thermal pain in normal volunteers. Significant interactions were found between pre- and post-exposure activation between the sham and exposed groups for the ipsilateral (right) insula, anterior cingulate and bilateral hippocampus/caudate areas. These results show, for the first time, that the neuromodulation induced by exposure to low-intensity low-frequency magnetic fields can be observed in humans using functional brain imaging and that the detection mechanism for these effects may be different from those used by animals for orientation and navigation. Magnetoreception may be more common than presently thought. 相似文献
94.
Magat Julie Ozenne Valéry Cedilnik Nicolas Naulin Jérôme Haliot Kylian Sermesant Maxime Gilbert Stephen H. Trew Mark Haissaguerre Michel Quesson Bruno Bernus Olivier 《Magma (New York, N.Y.)》2021,34(5):741-755
Magnetic Resonance Materials in Physics, Biology and Medicine - The aim of the study is to compare structure tensor imaging (STI) with diffusion tensor imaging (DTI) of the sheep heart... 相似文献
95.
A (Triphenylphosphine)Silver (I) Complex as a New Performance Additive in Free‐Radical Photopolymerization under Air 下载免费PDF全文
Pauline Sautrot‐Ba Nicolas Bogliotti Arnaud Brosseau Julie Bourgon Pierre‐Emmanuel Mazeran Jacques Lalevée Fabrice Morlet‐Savary Davy‐Louis Versace 《大分子材料与工程》2018,303(8)
Unusual photochemical properties of an Ag(I)‐derived complex, i.e., bis[(µ‐chloro)bis(triphenylphosphine)silver (I)] ([Ag](PPh3)) are demonstrated when used in free‐radical photopolymerization reactions: i) [Ag](PPh3) can act as an innovative photoinitiating system when associated with a commercial type I photoinitiator 2,2‐dimethoxy‐2‐phenylacetophenone to overcome the oxygen inhibition effect during the free‐radical photopolymerization of acrylate monomers, thus accelerating the kinetics of polymerization under air; ii) silver‐based nanoparticles can be in situ generated under air, thus leading to new antibacterial coatings which prevent the growth of Escherichia coli and Staphylococcus aureus after few hours of incubation. 相似文献
96.
97.
98.
Imalka H. A. M. Arachchilage Milly K. Patel Joseph Basi Julie P. Harmon 《Polymer Engineering and Science》2020,60(3):607-618
In the modern world, petroleum-based synthetic polymers have a great number of applications in fields ranging from food packaging to space travel. However, the processing of petroleum products and the resulting depletion of fossil fuels are major environmental concerns in today's society. As a result, the development of sustainable polymers which are made up of renewable resources and waste products is an immerging area of research. Considering the world food production, citrus fruit is most abundant and its contribution to waste generation is immense. Therefore, this study focuses on offering an alternative to the use of petroleum-based polymers and also providing a regulatory pathway to manage citrus waste by developing novel copolymers of laccol and limonene. Two environmentally friendly compounds, laccol, derived from the sap of Toxicodendron succedaneum tree and limonene, extracted from orange peels, were copolymerized via cationic polymerization to generate d-limonene:laccol copolymers with radiation hardening capabilities which is relevant in fields such as nuclear energy generation, medicinal sterilization, commercial irradiation, and space exploration. Formation of these copolymers was verified with infrared and nuclear magnetic resonance analysis. The synthesized copolymers were characterized using different methods and exposed to Co-60 gamma radiation to identify alterations to their properties. POLYM. ENG. SCI., 60:607–618, 2020. © 2019 Society of Plastics Engineers 相似文献
99.
Maxim Stolyarchuk Julie Ledoux Elodie Maignant Alain Trouv Luba Tchertanov 《International journal of molecular sciences》2021,22(2)
Redox (reduction–oxidation) reactions control many important biological processes in all organisms, both prokaryotes and eukaryotes. This reaction is usually accomplished by canonical disulphide-based pathways involving a donor enzyme that reduces the oxidised cysteine residues of a target protein, resulting in the cleavage of its disulphide bonds. Focusing on human vitamin K epoxide reductase (hVKORC1) as a target and on four redoxins (protein disulphide isomerase (PDI), endoplasmic reticulum oxidoreductase (ERp18), thioredoxin-related transmembrane protein 1 (Tmx1) and thioredoxin-related transmembrane protein 4 (Tmx4)) as the most probable reducers of VKORC1, a comparative in-silico analysis that concentrates on the similarity and divergence of redoxins in their sequence, secondary and tertiary structure, dynamics, intraprotein interactions and composition of the surface exposed to the target is provided. Similarly, hVKORC1 is analysed in its native state, where two pairs of cysteine residues are covalently linked, forming two disulphide bridges, as a target for Trx-fold proteins. Such analysis is used to derive the putative recognition/binding sites on each isolated protein, and PDI is suggested as the most probable hVKORC1 partner. By probing the alternative orientation of PDI with respect to hVKORC1, the functionally related noncovalent complex formed by hVKORC1 and PDI was found, which is proposed to be a first precursor to probe thiol–disulphide exchange reactions between PDI and hVKORC1. 相似文献
100.
Estève Ernault Julie Diani Simon Hallais Clio Cocquet 《Polymer Engineering and Science》2021,61(7):1971-1981
The mechanical behaviors of five polyether block amide foams, obtained by mold-opening foam injection process, were investigated with regard to their microstructures. The materials vary in mass ratios of hard versus soft segments, and/or in process packing time. The resulting microstructures have been characterized in terms of cavity size and shape ratios, by analyzing scanning electron microscope images after careful sample preparation. The foam mechanical responses have been characterized in compression at small and large strain. At small strain, the initial linear part of the stress–strain curve is enhanced firstly by the hard segment mass ratio and secondly by the fineness of the microstructure. Similar results have been obtained at large strain. The foam viscoelasticity at large strain has been characterized by stress relaxation and strain recovery tests, relevant for foam applications. Reduced packing time and pressure have been shown to lead to the presence of undesired large cavities. The morphological defects appear to have a negligible impact on the macroscopic mechanical behavior of the foams at infinitesimal strain, but lead to critical inconsistency at large strain. Furthermore, the mechanical behavior of the tested polyether block amide foams is controlled first by hard versus soft segments ratio, and second by the microstructure fineness. 相似文献