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861.
Costa Stefania Rugiero Irene Pedrini Paola Bernardi Tatiana Tamburini Elena 《平面色谱法杂志一现代薄层色谱法》2017,30(3):170-174
JPC – Journal of Planar Chromatography – Modern TLC - Quantification of carbohydrates and metabolites in fermentation processes can be considered as key factor in determining yield and... 相似文献
862.
Asef Nazari Dhananjay Thiruvady Aldeida Aleti Irene Moser 《The Journal of the Operational Research Society》2016,67(8):1050-1060
Component deployment is a combinatorial optimisation problem in software engineering that aims at finding the best allocation of software components to hardware resources in order to optimise quality attributes, such as reliability. The problem is often constrained because of the limited hardware resources, and the communication network, which may connect only certain resources. Owing to the non-linear nature of the reliability function, current optimisation methods have focused mainly on heuristic or metaheuristic algorithms. These are approximate methods, which find near-optimal solutions in a reasonable amount of time. In this paper, we present a mixed integer linear programming (MILP) formulation of the component deployment problem. We design a set of experiments where we compare the MILP solver to methods previously used to solve this problem. Results show that the MILP solver is efficient in finding feasible solutions even where other methods fail, or prove infeasibility where feasible solutions do not exist. 相似文献
863.
Allan N. Soriano Denise Irene V. Cabahug Meng-Hui Li 《The Journal of chemical thermodynamics》2011,43(2):186-189
In this present work, a thermophysical property characterization of aqueous solution of tris(hydroxymethyl)aminomethane (TRIS), a biological buffer, was done. The investigated properties were refractive index (n), density (ρ), and electrolytic conductivity (κ). These properties were measured for temperatures up to 353.15 K (at normal atmospheric condition) and for the entire composition range where TRIS is still soluble in water. The measured properties were reported as functions of temperature and composition. A modified form of the Vogel–Tamman–Fulcher equation which leads to an Arrhenius-type asymptotic exponential function was used to generally correlate the temperature and compositional dependence of the considered properties and satisfactory results were obtained. 相似文献
864.
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867.
Consuelo Pizarro Irene Arenzana-Rámila Nuria Pérez-del-Notario Patricia Pérez-Matute José María González-Sáiz 《Analytica chimica acta》2016
Lipid profiling is a promising tool for the discovery and subsequent identification of biomarkers associated with various diseases. However, data quality is quite dependent on the pre-analytical methods employed. To date, potential confounding factors that may affect lipid metabolite levels after the thawing of plasma for biomarker exploration studies have not been thoroughly evaluated. In this study, by means of experimental design methodology, we performed the first in-depth examination of the ways in which thawing conditions affect lipid metabolite levels. After the optimization stage, we concluded that temperature, sample volume and the thawing method were the determining factors that had to be exhaustively controlled in the thawing process to ensure the quality of biomarker discovery. Best thawing conditions were found to be: 4 °C, with 0.25 mL of human plasma and ultrasound (US) thawing. The new US proposed thawing method was quicker than the other methods we studied, allowed more features to be identified and increased the signal of the lipids. In view of its speed, efficiency and detectability, the US thawing method appears to be a simple, economical method for the thawing of plasma samples, which could easily be applied in clinical laboratories before lipid profiling studies. 相似文献
868.
Alexandros Kiriazis Gustav Boije af Gennäs Virpi TalmanElina Ekokoski Timo Ruotsalainen Irene KylänlahtiTobias Rüffer Gloria Wissel Henri XhaardHeinrich Lang Raimo K. TuominenJari Yli-Kauhaluoma 《Tetrahedron》2011,67(45):8665-8670
Protein kinase C (PKC) is a widely studied molecular target for the treatment of cancer and other diseases. We have approached the issue of modifying PKC function by targeting the C1 domain in the regulatory region of the enzyme. By using the X-ray crystal structure of the PKCδ C1b domain combined with molecular modeling, we discovered (3-aminodecahydro-1,4-methanonaphthalen-2-yl)methanol as a novel C1 domain ligand. The stereoselective synthesis of this tricyclic γ-amino alcohol was based on two successive Diels-Alder reactions to construct the six continuous stereocenters of the key intermediate. 相似文献
869.
Elgte Elmin B. de PaulaLorenzo C. Visentin Maria Irene YoshidaLuiz Fernando C. De Oliveira Flávia C. Machado 《Polyhedron》2011,30(2):213-220
Two new coordination polymers {[Mn2(BPP)2(C5O5)2(OH2)4]·3H2O}n (1) and {[Cu4(BPP)4(C5O5)4]·8H2O}n (2) [BPP = 1,3-bis(4-pyridyl)propane and C5O52− = croconate anion] were synthesized and characterized by thermal analysis, vibrational spectroscopy (Raman and infrared) and single crystal X-ray diffraction analysis. Compound 1 was obtained under solvothermal conditions and 2 by the diffusion method. Structure determination by single crystal X-ray diffraction analysis revealed that compound 1 presents two-dimensional polymeric nature due to the bridging coordination mode of both BPP ligand and croconate anion. In this case, the croconate anion acts in the unprecedented μ-1,2-bis(monodentate) coordination mode, forming interpenetrated grids of 63 topology. On the other hand, compound 2 is a three-dimensional 4-connected uninodal net of (42·84) topology, due to the presence of the flexible BPP ligand that bridges two Cu(II) sites connecting perpendicular one-dimensional polymeric chains, formed by croconate anions coordinated to the metal centers in a bis-bidentate coordination mode. 相似文献
870.
In order to establish which are the contribution of linear (total), hyperbolic (partial) or parabolic inhibitions by cellobiose,
and also a special case of substrate inhibition, the kinetics of cellobiohydrolase Cel7A obtained from Trichoderma reesei was investigated. Values of kinetic parameters were estimated employing integrated forms of Michaelis–Menten equations through
the use of non-linear regression, and criteria for selecting inhibition models are discussed. With cellobiose added at the
beginning of the reaction, it was found that cellulose hydrolysis follows a kinetic model, which takes into account a mixed
hyperbolic inhibition, by cellobiose with the following parameter values: K
m 5.0 mM, K
ic 0.029 mM, K
iu 1.1 mM, k
cat 3.6 h−1 and k
cat′ 0.2 h−1. Cellulose hydrolysis without initial cellobiose added also follows the same inhibition model with similar values (4.7, 0.029
and 1.5 mM and 3.2 and 0.2 h−1, respectively). According to Akaike information criterion, more complex models that take into account substrate and parabolic
inhibitions do not increase the modulation performance of cellulose hydrolysis. 相似文献