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131.
132.
Andrea De Pieri Sofia Ribeiro Dimitrios Tsiapalis David Eglin Marc Bohner Peter Dubruel Philip Procter Dimitrios I. Zeugolis Yves Bayon 《Journal of materials science. Materials in medicine》2018,29(8):129
The 4th Translational Research Symposium (TRS) was organised at the annual meeting of the European Society for Biomaterials (ESB) 2017, Athens, Greece, with a focus on ‘Academia—Industry Clusters of Research for Innovation Catalysis’. Collaborations between research institutes and industry can be sustained in several ways such as: European Union (EU) funded consortiums; syndicates of academic institutes, clinicians and industries; funding from national governments; and private collaborations between universities and companies. Invited speakers from industry and research institutions presented examples of these collaborations in the translation of research ideas or concepts into marketable products. The aim of the present article is to summarize the key messages conveyed during these lectures. In particular, emphasis is put on the challenges to appropriately identify and select unmet clinical needs and their translation by ultimately implementing innovative and efficient solutions achieved through joint academic and industrial efforts. 相似文献
133.
Sidra N. Ahmed Mushtaq Ahmad Muhammad Zafar Sofia Rashid Ghulam Yaseen Shazia Sultana Zafar Siddiq Omer Kilic Fethi A. Ozdemir Sadaf Kayani 《Microscopy research and technique》2019,82(7):1174-1183
The medicinal plants are utilized globally considering the cheap and chemical free source, but their correct identification and authentication is prerequisite for safety and efficacy of plant‐based medicines. The present study encompassed traded medicinal plants (16) with high therapeutic value from diverse families like Brassicaceae, Berberidaceae, Malvaceae, Salicaceae, Myrtaceae, Papilionaceae, Ascelpiadaceae, Colchicaceae, Violaceae, and Vitaceae for detailed microscopic study of characters that is, morphology, pollen shape and sizes, P/E ratio, pore length and width, spine length, colpi dimensions, and exine sculpture pattern. The plants showed noteworthy differences in microscopy of Wattakaka volubilis having pollinia, translator and corpusculum like structures while pores were visible in Colchicum luteum, Alcea rosea, and Hibiscus syriacus. The spines were observed in Centipeda minima, A. rosea, and H. syriacus being dimorphic spines in A. rosea and monomorphic in H. syriacus. The exine sculpturing pattern was reticulate in mostly studied plants however distinctive exine pattern was noted in Berberis aristata and Berberis lyceum. The highest polar diameter, equatorial diameter and exine thickness among studied plants were observed in H. syriacus (161 μm), C. luteum (50 μm) and Vitis jacquemontii (1.10), respectively. Thus, microscopy of medicinal plants in addition to other taxonomic evidence offers a supportive skill in authentication, consequently utilization by local consumers and pharmaceutical industries. 相似文献
134.
135.
Listeria monocytogenes is a Gram-positive bacterium that can adapt to high salinity and cold. Because the membrane lipids may play a role in its
survival and adaptation, we have examined the polar lipids ofL. monocytogenes. Extraction of total lipids fromL. monocytogenes yielded 7±1 mg/mL wet cells. Polar lipids represented 64% of total lipids and contained 9% lipid-phosphorus. Polar lipids
were separated into 14 components by two-dimensional thin-layer chromatography. Eight components (88% of polar lipids) contained
lipid-phosphorus; among these was one major component (34% of polar lipids). Two other phospholipids were ninhydrin-positive
components and accounted for 15% of the polar lipids. Orcinol staining revealed two glyco- or sulfo-lipids accounting for
9% of polar lipids. Five components (4% of polar lipids) were amino components free of phosphorus. The major component contained
46% of its fatty acids as 15:0anteiso, 24% as 17:0anteiso, and 11% as 15:0iso. The fatty acid profile of the remaining polar lipids was variable, consisting primarily of 16:0, 18:0, 15:0anteiso, and 17:0anteiso. Their unsaturation level was ≤20%; however, the major phosphoaminolipid component was 46% unsaturated. The ratios of 15:0anteiso/17:0anteiso and 15:0anteiso/15:0iso were similar in all classes, averaging 1.5 and 4.5, respectively. Since the adaptation process to stressful environments
involves activation of a membrane transport system for the protectant glycine betaine, the membrane lipids may play a role
in enabling transport. 相似文献
136.
Amélia M. Gonçalves da Silva Maria Isabel Viseu Cláudia Sofia Campos Teresa Rechena 《Thin solid films》1998,320(2):236-240
Mixed monolayers of dioctadecyldimethylammonium bromide (DODAB) with sodium hexadecylsulfate (SHS) can be obtained by spreading both components at the interface, co-spread (1) or separately spread (2), or by incorporation of the water soluble surfactant SHS from the subphase (3). The most efficient procedure is co-spreading, when equimolar amounts are used. On the other hand, when the components are spread separately at the interface, or when SHS is adsorbed from the aqueous subphase, it is not possible to obtain an efficiency as high as that of co-spreading, even after 5 h. The equimolar composition at the interface can also be immediately obtained after solvent evaporation when SHS is added to the subphase in large excess to DODAB (9:1); alternatively, the same composition can be obtained from smaller excesses of SHS to DODAB, but only after larger time intervals. The composition of the mixed monolayers obtained by procedures 2 and 3 was estimated from the correlation compressibility–composition, obtained independently by co-spreading. 相似文献
137.
Fahim Sadek Sofia Diniz Michael Kasperski Massimiliano Gioffrè Emil Simiu 《Canadian Metallurgical Quarterly》2004,130(2):235-239
Peak values in time histories of wind effects may be obtained by using the entire information inherent in the time series of the wind effect, a method entailing the estimation of the probability distribution of the peak through the application of the classical Rice procedure extended for non-Gaussian time histories. We present estimates of the sampling errors inherent in this method. These are needed for structural reliability calculations and for decisions on the requisite length of wind tunnel pressure records, especially for database-assisted design. If based on the analysis of 1-h-long records generated by Monte Carlo simulation, typical sampling errors in the estimation of peaks of time histories corresponding to windstorms of 1-h duration are about 5%. If based on 30- or 20-min records, they are about 1.5 times or twice as large, respectively. Consideration of the sampling errors in reliability calculations entails an estimated increase in the requisite safety margins with respect to wind loading of roughly 2, 3, and 5% if 1-h, 30-min, or 20-min records are used, respectively. 相似文献
138.
To achieve structures that are risk-consistent, structural reliability methods must be used that account for uncertainties with respect to the relevant parameters affecting the estimation of wind effects. In this paper, we obtain measures of uncertainties in the estimation of the wind speeds upwind of structures. These uncertainties are due to incomplete knowledge with respect to the relevant extreme climatological and micrometeorological parameters. Advances in wind engineering and improvements in computational capabilities now make it possible to improve upon earlier estimates available in the literature. The work presented in this paper is a phase of a broader NIST project aimed at developing user-friendly software for the estimation of probabilities of failure of low-rise structures subjected to wind loads. 相似文献
139.
Poly(ethylene oxide) (PEO) polymer, in linear and star form, was covalently grafted to silicon surfaces, and the surfaces were tested for their ability to adsorb proteins. Linear PEG of molecular weight 3400, 10 000, and 20 000 g/mol and star PEO molecules were coupled via their terminal hydroxyl groups activated by tresyl chloride to aminosilane-treated silicon wafers. The amount of PEO coupled to the surface was varied by changing the concentration of the tresyl-PEO solution. The dry PEO thickness on the surface was measured using X-ray photoelectron spectroscopy (XPS) and ellipsometry, from which the grafting density was calculated. The PEO surfaces were exposed to solutions of each of three proteins: cytochrome-c, albumin, and fibronectin. The degree of adsorption of each protein was determined by XPS and ellipsometry and recorded as a function of PEO grafting density. All three proteins were found to reach zero adsorption at the highest grafting densities on all three PEG surfaces, which for all three PEG surfaces was a PEO content of 100 +/- 10 ng/cm2. On both star PEO surfaces, albumin and fibronectin decreased to zero adsorption at intermediate values of grafting density, whereas cytochrome-c continued to adsorb at all grafting densities, although with a decreasing trend. A physical model of the surface helped explain these protein adsorption results in terms of the spacing and degree of overlap of grafted PEO chains. 相似文献
140.
Effect of lead on the uptake of nutrients by unicellular algae 总被引:2,自引:0,他引:2
From batch growth experiments carried out with the alga Selenastrum capricornutum Printz the evolution of uptake of nitrogen and phosphorus with time in the absence and presence of lead 1 × 10−6 M and at pH 7 and 4 has been considered. The change of pigments (chlorophylls a, b and vegetal carotenoids) with time, as well as the labile and total lead in the medium and in the alga and the fluorescence compounds released by the alga, have also been analysed.Relationships between phosphorus in the alga and the pigments and lead in the cell, as well as between phosphorus and fluorescence compounds exudated by each unit of the unicellular alga, have been examined in order to try to understand the biochemical mechanism. 相似文献