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排序方式: 共有385条查询结果,搜索用时 31 毫秒
1.
Dr. Emrah Kara Dr. Nis Valentin Nielsen Bergrun Eggertsdottir Dr. Bernd Thiede Dr. Sandip M. Kanse Dr. Geir Åge Løset 《Chembiochem : a European journal of chemical biology》2020,21(13):1875-1884
We describe a novel, easy and efficient combinatorial phage display peptide substrate-mining method to map the substrate specificity of proteases. The peptide library is displayed on the pVII capsid of the M13 bacteriophage, which renders pIII necessary for infectivity and efficient retrieval, in an unmodified state. As capture module, the 3XFLAG was chosen due to its very high binding efficiency to anti-FLAG mAbs and its independency of any post-translational modification. This library was tested with Factor-VII activating protease (WT-FSAP) and its single-nucleotide polymorphism variant Marburg-I (MI)-FSAP. The WT-FSAP results confirmed the previously reported Arg/Lys centered FSAP cleavage site consensus as dominant, as well as reinforcing MI-FSAP as a loss-of-function mutant. Surprisingly, rare substrate clones devoid of basic amino acids were also identified. Indeed one of these peptides was cleaved as free peptide, thus suggesting a broader range of WT-FSAP substrates than previously anticipated. 相似文献
2.
3.
The solubility of aluminum in NaF-AlF3-Al2O3 melts with various additives was found to increase with increasing NaF/AlF3 molar ratio (CR) and increasing temperature and to decrease with additions of A12O3, CaF2, MgF2, and LiF to the melts. With the use of literature data for the activities of NaF and A1F3 in cryolitic melts, three dissolution reaction models were found to give a good fit to the experimental solubility data.
According to the most probable of these models the total concentration of dissolved aluminum (aluminum and sodium species)
is given by cAl = cNa(diss) + cAlF2- + cAl2F3- + cAl3F4- + cAl4F5- In NaF rich melts, aluminum will dominantly dissolve as sodium, while at cryolite ratios commonly used in aluminum electrowinning
(CR = 2.25 to 2.7) the AlF
-2
-
-ion is the predominant dissolved metal species. Other species (A12F3
-, A13F4-, A14F5-) were found to be of some significance only in melts with high excess A1F3 (CR < 2). 相似文献
4.
The solubility of aluminum in NaF-AlF3-Al2O3 melts with various additives was found to increase with increasing NaF/AlF3 molar ratio (CR) and increasing temperature and to decrease with additions of A12O3, CaF2, MgF2, and LiF to the melts. With the use of literature data for the activities of NaF and A1F3 in cryolitic melts, three dissolution reaction models were found to give a good fit to the experimental solubility data. According to the most probable of these models the total concentration of dissolved aluminum (aluminum and sodium species) is given by cAl = cNa(diss) + cAlF2- + cAl2F3- + cAl3F4- + cAl4F5- In NaF rich melts, aluminum will dominantly dissolve as sodium, while at cryolite ratios commonly used in aluminum electrowinning (CR = 2.25 to 2.7) the AlF -2 - -ion is the predominant dissolved metal species. Other species (A12F3 -, A13F4-, A14F5-) were found to be of some significance only in melts with high excess A1F3 (CR < 2). 相似文献
5.
The kinetics of aluminium deposition from NaCl-AlCl3 melts (cAlCl3 < 10 mol%) contained in alumina crucibles was studied by linear sweep voltammetry and potential step amperometry at temperatures around 820°C. At low concentrations (cAlCl3 < 0.4 mol%) the reduction of AlCl3 on liquid aluminium has been found to be diffusion controlled. At higher concentrations a passivation of the aluminium electrode was observed during the deposition reaction. The passivation appears to be caused by precipitation of alumina from supersaturated melt in the diffusion layer at the aluminium cathode. 相似文献
6.
The low temperature crystallization technique for the enrichment of “minor” components, such as sterols and sterol esters,
from vegetable oils was applied to low erucic acid rapeseed oils. The recovery of free sterols and sterol esters was estimated
by use of14C-cholesterol and14C-cholesterol oleate. 80% of the free sterols and 45% of the sterol esters were recovered in the liquid fraction, while in
two studies total recoveries were 95% and 99%, respectively. This technique showed some selectivity toward the sterol bound
fatty acids when compared to direct preparative thin layer chromatography (TLC) of the crude oil. Gas liquid chromatography
(GLC) analysis of the free and esterified sterols as TMS-derivatives showed very little selectivity in the enrichment procedure.
The fatty acid patterns of the sterol esters demonstrated, however, a preference in the liquid fraction for those sterol esters
which have a high linoleic and linolenic acid content. The content of free sterols was 0.3–0.4% and that of sterol esters
0.7–1.2% of the rapeseed oils in both winter and summer types of low erucic acid rapeseed (Brassica napus) when the lipid classes were isolated by direct preparative TLC of the oils. The free sterols in the seven cultivars or breeding
lines analyzed were composed of 44–55% sitosterol, 27–36% campesterol, 17–21% brassicasterol, and a trace of cholesterol.
The esterified sterols were 47–57% sitosterol, 36–44% campesterol, 6–9% brassicasterol, and traces of cholesterol and Δ5-avenasterol.
The fatty acid patterns of these esters were characterized by ca. 30% oleic acid and ca. 50% linoleic acid, whereas these
acids constitute 60% and 20%, respectively, of the total fatty acids in the oil. Little or no variation in sterol and sterol
ester patterns with locality within Sweden was observed for the one cultivar of summer rapeseed investigated by the low temperature
crystallization technique. 相似文献
7.
Oscar Ljungkrantz Knut Åkesson Martin Fabian Amir Hossein Ebrahimi 《Empirical Software Engineering》2014,19(3):655-677
This paper presents an empirical study of control logic specifications used to document industrial control logic code in manufacturing applications. More than one hundred input/output related property specifications from ten different reusable function blocks were investigated. The main purpose of the study was to provide understanding of how the specifications are expressed by industrial practitioners, in order to develop new tools and methods for specifying control logic software, as well as for evaluating existing ones. In this paper, the studied specifications are used to evaluate linear temporal logic in general and the specification language ST-LTL, tailored for functions blocks, in particular. The study shows that most specifications are expressed as implications, that should always be fulfilled, between input and output conditions. Many of these implications are complex since the input and output conditions may be mixed and involve sequences, timer issues and non-boolean variables. Using ST-LTL it was possible to represent all implications of this study. The few non-implication specifications could be specified in ST-LTL as well after being altered to suit the specification language. The paper demonstrates some advantages of ST-LTL compared to standard linear temporal logic and discusses possible improvements such as support for automatic rewrite of complex specifications. 相似文献
8.
Afaf Kamal-Eldin Lars Åke Appelqvist 《Journal of the American Oil Chemists' Society》1994,71(2):149-156
Seeds from different collections of cultivatedSesamum indicum Linn and three related wild species [specifically,S. alatum Thonn.,S. radiatum Schum & Thonn. andS. angustifolium (Oliv.) Engl.] were studied for their oil contents and fatty acid composition of the total lipids. The oils from wild seeds
were characterized by higher percentages of unsaponifiables (4.9, 2.6 and 3.7%, respectively) compared toS. indicum (1.4–1.8%), mainly due to their high contents of lignans. Total sterols accounted forca. 40, 22, 20 and 16% of the unsaponifiables of the four species, respectively. The four species were different in the relative
percentages of the three sterol fractions (the desmethyl, monomethyl and dimethyl sterols) and in the percentage composition
of each fraction. Campesterol, stigmasterol, sitosterol and Δ5-avenasterol were the major desmethyl sterols, whereas obtusifoliol, gramisterol, cycloeucalenol and citrostandienol were
the major monomethyl sterols, and α-amyrin, β-amyrin, cycloartenol and 24-methylene cycloartanol were the main dimethyl sterols
in all species. Differences were also observed among the four species in sterol patterns of the free sterols compared to the
sterol esters.Sesamum alatum contained less tocopherols (210–320 mg/kg oil), andS. radiatum andS. angustifolium contained more tocopherols (ca. 750 and 800 mg/kg oil, respectively) than didS. indicum (490–680 mg/kg oil). The four species were comparable in tocopherol composition, with γ-tocopherol representing 96–99% of
the total tocopherols. The four species varied widely in the identity and levels of the different lignans. The percentages
of these lignans in the oils ofS. indicum were sesamin (0.55%) and sesamolin (0.50%).Sesamum alatum showed 1.37% of 2-episesalatin and minor amounts of sesamin and sesamolin (0.01% each).Sesamum radiatum was rich in sesamin (2.40%) and contained minor amounts of sesamolin (0.02%), whereS. angustifolium was rich in sesangolin (3.15%) and also contained considerable amounts of sesamin (0.32%) and sesamolin (0.16%). 相似文献
9.
Preparation of anchored ceramic coatings on metal substrates: a modified sol-gel technique using colloidal silica sol 总被引:1,自引:0,他引:1
M. F. M. Zwinkels S. G. Järås P. Govind Menon Knut I. Åsen 《Journal of Materials Science》1996,31(23):6345-6349
A single-step dip-coating technique was developed to produce stable films or washcoats of controlled thickness, surface area and pore-size distribution on alumina whisker-covered metal substrates (both flat plates and monoliths). Dip-coating slurries were prepared by dispersing fine porous powder in a colloidal silica sol. The method provided control over coating thickness and coating properties, such as pore-size distribution and surface area. The coating thickness could be varied between approximately 2 and 40 m by selecting slurry composition and withdrawal speed in the dipping procedure. The pore-size distribution and surface area could be varied by changing type and amount of porous filler material in the dipping slurry. Uniform and bimodal pore-size distributions were obtained using silica and ZSM-5 molecular sieves, respectively, yielding coatings with surface areas between 60 and 400 m2g–1. 相似文献
10.
Asbjørn Solheim Sverre Rolseth Egil Skybakmoen Lisbet Støen Åsmund Sterten Trond Støre 《Metallurgical and Materials Transactions B》1996,27(5):739-744
Temperatures for primary crystallization of Na3AlF6 in multicomponent electrolyte systems of interest for the aluminum electrolysis process were determined by thermal analysis. The results are presented as binary and quasibinary diagrams and discussed in view of the literature data. An empirical equation describing liquidus temperatures for primary crystallization of Na3AlF6 was derived: $$\begin{gathered} t/(^\circ C) = 1011 + 0.50[AlF_3 ] - 0.13[AIF_3 ] - \frac{{3.45[CaF_2 ]}}{{1 + 0.0173[CaF_2 ]}} \hfill \\ + 0.124[CaF_2 ] \cdot [AlF_3 ] - 0.00542([CaF_2 ] \cdot [AlF_3 ])^{1.5} \hfill \\ - \frac{{7.93[Al_2 O_3 ]}}{{1 + 0.0936[Al_2 O_3 ] - 0.0017[Al_2 O_3 ]^2 - 0.0023[AlF_3 ] \cdot [Al_2 O_3 ]}} \hfill \\ - \frac{{8.90[LiF]}}{{1 + 0.0047[LiF] + 0.0010[AlF3]^2 }} - 3.95[MgF_2 ] - 3.95 \hfill \\ \end{gathered} $$ wheret is the temperature in degree Celsius and the square brackets denote the weight percent of components in the system Na3AlF6-AlF3-CaF2-Al2O3-LiF-MgF2-KF. The composition limitations are [AlF3] ≈ [CaF2] ≈ [LiF] < 20 wt pct, [MgF2] ≈ [KF] < 5 wt pct, and [A12O3] up to saturation. 相似文献