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981.
982.
Edwin Kroon Jrg O. Schulze Evelyn Süß Carlos J. Camacho Ricardo M. Biondi Alexander Dmling 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2015,127(47):14139-14142
The rational design of allosteric kinase modulators is challenging but rewarding. The protein kinase PDK1, which lies at the center of the growth‐factor signaling pathway, possesses an allosteric regulatory site previously validated both in vitro and in cells. ANCHOR.QUERY software was used to discover a potent allosteric PDK1 kinase modulator. Using a recently published PDK1 compound as a template, several new scaffolds that bind to the allosteric target site were generated and one example was validated. The inhibitor can be synthesized in one step by multicomponent reaction (MCR) chemistry when using the ANCHOR.QUERY approach. Our results are significant because the outlined approach allows rapid and efficient scaffold hopping from known molecules into new easily accessible and biologically active ones. Based on increasing interest in allosteric‐site drug discovery, we foresee many potential applications for this approach. 相似文献
983.
Nucleation,Crystallization, and Thermal Fractionation of Poly (ε‐Caprolactone)‐Grafted‐Lignin: Effects of Grafted Chains Length and Lignin Content
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Ricardo A. Pérez–Camargo Guery Saenz Stéphanie Laurichesse María Teresa Casas Jordi Puiggalí Luc Avérous Alejandro J. Müller 《Journal of Polymer Science.Polymer Physics》2015,53(24):1736-1750
Poly(ε‐caprolactone)‐grafted‐lignin (PCL‐g‐lignin) copolymers with 2 to 37 wt % lignin are employed to study the effect of lignin on the morphology, nucleation, and crystallization kinetics of PCL. Lignin displays a nucleating action on PCL chains originating an intersecting lamellar morphology. Lignin is an excellent nucleating agent for PCL at low contents (2–5 wt %) with nucleation efficiency values that are close to or >100%. This nucleating effect increases the crystallization and melting temperature of PCL under nonisothermal conditions and accelerates the overall isothermal crystallization rate of PCL. At lignin contents >18 wt %, antinucleation effects appear, that decrease crystallization and melting temperatures, reduce crystallinity degree, hinder annealing during thermal fractionation and significantly retard isothermal crystallization kinetics. The results can be explained by a competition between nucleating effects and intermolecular interactions caused by hydrogen bonding between PCL and lignin building blocks. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2015 , 53, 1736–1750 相似文献
984.
Philip D. P. Taylor Danuta Barałkiewicz Ricardo Bettencourt da Silva Darinka Brodnjak Vončina Ewa Bulska Maria Filomena Camoes Ryszard Dobrowolski Marc Elskens Ivo Leito Nineta H. Majcen Petko Mandjukov Josephine McCourt Jérôme Randon Paavo Perämäki 《Analytical and bioanalytical chemistry》2015,407(23):6899-6907
985.
Thandi P. Gumede Adriaan S. Luyt Ricardo A. Pérez‐Camargo Amaia Iturrospe Arantxa Arbe Manuela Zubitur Agurtzane Mugica Alejandro J. Müller 《Journal of Polymer Science.Polymer Physics》2016,54(15):1469-1482
The structure and thermal properties of linear low‐density polyethylene (LLDPE)/medium soft paraffin wax blends, prepared by melt mixing, were investigated by differential scanning calorimetry (DSC) and small‐ and wide‐angle X‐ray scattering (SAXS and WAXS). The blends form a single phase in the melt as determined by SAXS. Upon cooling from the melt, two crystalline phases develop for blends with more than 10 wt % wax characterized by widely different melting points. The wax acts as an effective plasticizer for LLDPE, decreasing both its crystallization and melting temperature. The higher melting point crystalline phase is formed by less branched LLDPE fractions. On the other hand, the lower melting point crystalline phase is a wax‐rich phase constituted by cocrystals of extended chain wax and short linear sequences of highly branched LLDPE chains. The presence of cocrystals was evidenced by standard DSC results, successive self‐nucleation and annealing (SSA) thermal fractionation and by the detection of a new SAXS signal attributed to the lamellar long period of the cocrystals. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016 , 54, 1469–1482 相似文献
986.
987.
Journal of High Energy Physics - The coset Sp(2, ℝ)/U(1) is parametrized by two real scalar fields. We generalize the formalism of auxiliary tensor (bispinor) fields in U(1) self-dual... 相似文献
988.
Malena Karla Lombello Coelho Hanna Leijoto De Oliveira Fernanda Garcia De Almeida Keyller Bastos Borges César Ricardo Teixeira Tarley 《International journal of environmental analytical chemistry》2017,97(14-15):1378-1392
A simple and fast voltammetric method based on a new electrode composed of carbon paste electrode/bifunctional hybrid ion imprinted polymer (CPE/IIP) was developed for the quantification of Cd2+ in water samples. The voltammetric measurements by Differential Pulse Voltammetry were performed by using CPE containing 11.0 mg of IIP under phosphate buffer solution at concentration 0.1 mol L?1 and pH 6.5. The electrochemical method was carried out by Cd2+ preconcentration at ?1.2 V during 210 s, followed by anodic stripping. The performance of IIP towards Cd2+ determination was evaluated by comparison to non-imprinted polymer, whose detectability of IIP was much higher (45%). The sensitivity of the sensor was found to be 0.0105 µA/µg L?1. The limits of detection and limits of quantification were found to be 4.95 μg L?1 and 16.4 μg L?1, respectively. The developed method was successfully applied to Cd2+ determination in mineral, tap and lake water samples, whose results are in agreement with thermospray flame furnace atomic absorption spectrometry (TS-FF-AAS) used as reference analytical technique. According to achieved results, the developed method can be used for routine analysis of quality control of water samples from different sources. 相似文献
989.