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排序方式: 共有1262条查询结果,搜索用时 31 毫秒
991.
Christopher A. Mills Javier G. Fernandez Abdelhamid Errachid Josep Samitier 《Microelectronic Engineering》2008,85(9):1897-1901
Polymers with high glass transition temperatures, fluorinated ethylene propylene copolymer (FEP) and poly(ethylene naphthalate) (PEN), have been used in imprint lithography as a protective support layer and as a secondary mould, to imprint superficial structures into a polymer with a lower glass transition temperature, namely poly(methyl methacrylate) (PMMA). As a support layer, FEP replaces fragile silicon based supports for the production of freestanding, structured sheets of PMMA, useful, for example, in biomedical applications where transmittance optical microscopy is required. Secondary PEN moulds, produced by imprinting using silicon-based primary moulds, have been used to transfer sub-micrometer tall structures to a freestanding PMMA sheet. Similarly, hole structures, with different dimensions, have been embossed in both sides of a PMMA sheet simultaneously. 相似文献
992.
The effect of RN(-) allele on minimally processed hams as manufactured in France is now well established. In the present study, meat from 35 rn(+) and 51 RN(-) pigs on the basis of their glycolytic potential (GP) was used to assess the effect of the RN(-) allele on a model system and on yields and quality of cooked hams cured with a 40% brine addition containing the most common meat processing ingredients. Quality parameters were also measured on the fresh loins and a glucose assay was carried out on meat juice from both hams and longissimus dorsi (LD) muscles. With respect to GP, glucose content of LD juice gave the best prediction of RN status with 10% misclassified samples in comparison with 20% as determined from ham juice. Lower pH and higher drip loss and L* values were measured on the LD from RN(-) pigs (p?0.001). Technological yields obtained on the model system and on extended cooked cured hams were lower in meat from RN(-) pigs (p?0.001). However, pH value was more influential on the yield of the model system while protein content and particularly the amount of extractable sarcoplasmic proteins were more determinative on cured hams probably due to the effect of tumbling. All other quality traits were lower in hams from RN(-) pigs (p?0.001). Meat from RN(-) pigs can be used for the manufacture of extended cured products, but under similar processing technologies, quality and yield will remain inferior to what would provide pork of normal quality. 相似文献
993.
Use of a fluoride channel as a new selection marker for fission yeast plasmids and application to fast genome editing with CRISPR/Cas9
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Fission yeast is a powerful model organism that has provided insights into important cellular processes thanks to the ease of its genome editing by homologous recombination. However, creation of strains with a large number of targeted mutations or containing plasmids has been challenging because only a very small number of selection markers is available in Schizosaccharomyces pombe. In this paper, we identify two fission yeast fluoride exporter channels (Fex1p and Fex2p) and describe the development of a new strategy using Fex1p as a selection marker for transformants in rich media supplemented with fluoride. To our knowledge this is the first positive selection marker identified in S. pombe that does not use auxotrophy or drug resistance and that can be used for plasmids transformation or genomic integration in rich media. We illustrate the application of our new marker by significantly accelerating the protocol for genome edition using CRISPR/Cas9 in S. pombe. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
994.
Studies investigated the effects of dietary fatty acid composition and saturation on the regulation of very low density lipoprotein
(VLDL) apo B flux, clearance, and conversion to low density lipoprotein (LDL) in guinea pigs fed semipurified diets containing
15% (w/w) corn oil (CO), lard (LA), or palm kernel oil (PK). Plasma cholesterol levels were highest with dietary PK (3.1±1.0
mmol/L) followed by LA (2.4±0.4 mmol/L) and CO (1.6±0.4 mmol/L) intake. VLDL particles were larger (P<0.05) in the LA (78±7 nm) and PK (69±10 nm) groups compared to animals fed CO (49±5 nm). VLDL-apo B fractional catabolic
rates (FCR) were highest in guinea pigs fed the LA diet (P<0.05) and VLDL apo B flux, estimated from VLDL 125I-apo B turnover kinetics, were higher in LA compared to PK or CO fed guinea pigs. In the case of PK consumption, the kinetic
estimates of VLDL apo B flux significantly underestimated rates compared to direct VLDL apo B secretion measurements and LDL
turnover analyses. These data demonstrate that differences in the composition and amount of saturated fatty acids have differential
effects on VLDL apo B flux, catabolism, and conversion to LDL which, together with changes in LDL receptor-mediated catabolism,
determine plasma LDL cholesterol levels in guinea pigs. The data also indicate that kinetic analysis of VLDL metabolism in
PK fed animals is inaccurate possibly due to the presence of a small, nonequilibrating pool of newly synthesized VLDL which
is rapidly converted to LDL. 相似文献
995.
Homopolymer polystyrene-divinylbenzene, PS-DVB, networks were made by free radical chemistry u.v. photopolymerization techniques, and characterized by small-angle neutron scattering (SANS). The networks contained a delta fraction of chains labelled with deuterium. Two different series of samples were made: Method A in which the insertion was made centrally or at the end of the polymerization; Method B in which the delta fraction of deuterated primary chains was inserted at the beginning of the polymerization. Method B samples yielded a molecular weight of about 70,000 g/mole and a radius of gyration of about 120 Å, values in the range expected for single primary chains. Method A samples, however, gave molecular weights of 1–2 million and radii of gyration ranging from 350 to 400 Å. Intrinsic viscosity and gel permeation chromatography (g.p.c.) studies on parallel fractions yielded weight-average molecular weights near 72,000 g/mole for most of the polymerization. These results strongly suggest the existence of aggregation of primary chains synthesized in the same conversion period within the network. A new method of characterizing crosslinking between network chains is proposed, since these experiments count the probability of a chain crosslinking with a chain polymerized immediately before in time. 相似文献
996.
Cassandria Geraldine Tay Fernandez Benjamin John Nestor Monica Furaste Danilevicz Mitchell Gill Jakob Petereit Philipp Emanuel Bayer Patrick Michael Finnegan Jacqueline Batley David Edwards 《International journal of molecular sciences》2022,23(5)
Pangenomes are a rich resource to examine the genomic variation observed within a species or genera, supporting population genetics studies, with applications for the improvement of crop traits. Major crop species such as maize (Zea mays), rice (Oryza sativa), Brassica (Brassica spp.), and soybean (Glycine max) have had pangenomes constructed and released, and this has led to the discovery of valuable genes associated with disease resistance and yield components. However, pangenome data are not available for many less prominent crop species that are currently under-utilised. Despite many under-utilised species being important food sources in regional populations, the scarcity of genomic data for these species hinders their improvement. Here, we assess several under-utilised crops and review the pangenome approaches that could be used to build resources for their improvement. Many of these under-utilised crops are cultivated in arid or semi-arid environments, suggesting that novel genes related to drought tolerance may be identified and used for introgression into related major crop species. In addition, we discuss how previously collected data could be used to enrich pangenome functional analysis in genome-wide association studies (GWAS) based on studies in major crops. Considering the technological advances in genome sequencing, pangenome references for under-utilised species are becoming more obtainable, offering the opportunity to identify novel genes related to agro-morphological traits in these species. 相似文献
997.
J. Hartung K. Rosenbaum L. Beyer J. Losada V. Fernandez 《Advanced Synthesis \u0026amp; Catalysis》1991,333(4):537-544
About the Reversible Conversion of 3-Diethylamino-5-phenyl-1,2,4-dithiazoliumhalometallates into Metal Chelates of 3-(Thio)benzoyl(thio)ureas Redox reactions of 3-diethylamino-5-phenyl-1, 2,4-dithiazolium halometallates 1a-e and metal chelates (M = CuII ( 2 A ), CoII ( 2 C ), NiII ( 2 F )) of 3-thiobenzoylthioureat was studied by cyclic voltammetry. 1 are converted by reduction into 2. The mechanism of the oxidation of 2 A , C , F into 1a , d , e is dependent on the central ion. On formation of 1 a from copper(II) chelates of 3-benzoylthiourea 3 A by means of thionylchloride as well as by electrochemical oxidation 3-benzoylureas 4 A are formed as sideproducts. 相似文献
998.
M. Thellier E. Hennequin C. Heurteaux F. Martini M. Pettersson T. Fernandez J.C. Wissocq 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》1988,30(4):567-579
Theoretical models are proposed for the calculation of the local concentrations, in a specimen, of nuclides such as 6Li, 10B, 14N or 17O, from the corresponding local densities of tracks on the detectors. Several different cases have been studied: i) one or several types of particle involved, ii) initial energy of the particles below, or above the “upper threshold of detection”, iii) possible nonnegligible abrasion of the detectors during etching and iv) contribution of background tracks originating from the detectors themselves. The theoretical equations have been applied to the interpretation of experimental data. 相似文献
999.
Cu–Ga–Se thin films were prepared using a combination of electrodeposition and evaporation techniques. A Cu–Se/Mo/glass precursor thin film was first prepared by galvanostatic electrodeposition. On top of this film three different thicknesses of Ga were deposited by evaporation. The Cu–Ga–Se thin films were formed by annealing the Ga/Cu–Se/Mo/glass thin film configuration in a tubular chamber with Se powder, at different temperatures. Thin films were characterized by X-ray diffraction (XRD), photocurrent spectroscopy (PS), inductively coupled plasma (ICP) analysis, and scanning electron microscopy (SEM). The detailed analysis from X-ray reveals that after annealing at 550 °C the CuGaSe2 phase is formed when the thickness of Ga is 0.25 μm, however at 0.5 μm and 1.0 μm Ga the formation of CuGa3Se5 and CuGa5Se8 phases is observed respectively. Band gap values were obtained using photocurrent spectroscopy. 相似文献
1000.
New process for simultaneous removal of nitrogen and sulphur under anaerobic conditions 总被引:12,自引:0,他引:12
Fdz-Polanco F Fdz-Polanco M Fernandez N Urueña MA Garcia PA Villaverde S 《Water research》2001,35(4):1111-1114
A granular activated carbon (GAC) anaerobic fluidised-bed reactor treating vinasse from an ethanol distillery of sugar beet molasses was operated for 90 days, the first 40 days of start-up followed by 50 days of operation at constant organic loading rate of 1.7g COD/Ld. The reactor showed good performance in terms of organic matter removal but an anomalous behaviour in terms of unusual high concentrations of molecular nitrogen in the biogas. The analysis of the different nitrogenous and sulphur compounds and the mass balances of these compounds in the liquid and gas phases clearly indicated an uncommon evolution of nitrogen and sulphur in the reactor. About 50% of the nitrogen entering the reactor as total Kjeldahl nitrogen (TKN) was removed from the liquid phase appearing as N2 in the gas phase. Simultaneously, only 20% of the S-SO4(2-) initially present in the influent appears as S-S2- in the effluent or S-H2S in the biogas, indicating that 80% of the sulphur is removed. This behaviour has not been reported previously in the literature. These observations may suggest a new anaerobic removal process of ammonia and sulphate according to an uncommon mechanism involving simultaneous anaerobic ammonium oxidation and sulphate reduction. 相似文献