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101.
102.
We examine whether cubic nonlinearities, allowed by symmetry in the elastic energy of a contact line, may result in a different universality class at depinning. Standard linear elasticity predicts a roughness exponent zeta = 1/3 (one loop), zeta = 0.388 +/- 0.002 (numerics) while experiments give zeta approximately = 0.5. Within functional renormalization group methods we find that a nonlocal Kardar-Parisi-Zhang-type term is generated at depinning and grows under coarse graining. A fixed point with zeta approximately = 0.45 (one loop) is identified, showing that large enough cubic terms increase the roughness. This fixed point is unstable, revealing a rough strong-coupling phase. Experimental study of contact angles theta near pi/2, where cubic terms in the energy vanish, is suggested.  相似文献   
103.
Contextuality is a particular quantum phenomenon that has no analogue in classical probability theory. Given two independent systems, a natural question is how to represent such a situation as a single test space. In other words, how separate contextuality scenarios combine into a joint scenario. Under the premise that the the allowed probabilistic models satisfy the No Signalling principle, Foulis and Randall defined the unique possible way to compose two contextuality scenarios. When composing strictly-more than two test spaces, however, a variety of possible composition methods have been conceived. Nevertheless, all these formally-distinct composition methods appear to give rise to observationally equivalent scenarios, in the sense that the different compositions all allow precisely the same sets of classical and quantum probabilistic models. This raises the question of whether this property of invariance-under-composition-method is special to classical and quantum probabilistic models, or if it generalizes to other probabilistic models as well, our particular focus being \(\mathcal {Q}_1\) models. \(\mathcal {Q}_1\) models are physically important since, when applied to scenarios constructed by a particular composition rule, coincide with the well-defined “Almost Quantum Correlations”. In this work we see that some composition rules, however, give rise to scenarios with inequivalent allowed sets of \(\mathcal {Q}_1\) models. We find that the non-trivial dependence of \(\mathcal {Q}_1\) models on the choice of composition method is apparently an artifact of failure of those composition rules to capture the orthogonality relations given by the Local Orthogonality principle. We prove that \(\mathcal {Q}_1\) models satisfy invariance-under-composition-method for all the constructive compositions protocols which do capture this notion of Local Orthogonality.  相似文献   
104.
ATP binding cassette (ABC) systems constitute one of the most abundant superfamilies of proteins. They are involved in the transport of a wide variety of substances, but also in many cellular processes and in their regulation. In this paper, we made a comparative analysis of the properties of ABC systems and we provide a phylogenetic and functional classification. This analysis will be helpful to accurately annotate ABC systems discovered during the sequencing of the genome of living organisms and to identify the partners of the ABC ATPases.  相似文献   
105.
We herein report the first enantioselective synthesis of two new monocyclic sesquiterpenes from Artemisia chamaemelifolia starting from an enantiopure building block. The key feature of the present approach is to allow complete control of all the stereogenic centers present in the natural products and to elucidate their absolute stereochemistry, which to date is unknown.  相似文献   
106.
Social insects are in mutualism with microorganisms, contributing to their resistance against infectious diseases. The fungus Pseudallescheria boydii SNB-CN85 isolated from termites produces ovalicin derivatives resulting from the esterification of the less hindered site of the ovalicin epoxide by long-chain fatty acids. Their structures were elucidated using spectroscopic analysis and semisynthesis from ovalicin. For ovalicin, these compounds displayed antiprotozoal activities against Plasmodium falciparum and Trypanosoma brucei, with IC50 values of 19.8 and 1.1 µM, respectively, for the most active compound, i.e., ovalicin linoleate. In parallel, metabolomic profiling of a collection of P. boydii strains associated with termites made it possible to highlight this class of compounds together with tyroscherin derivatives in all strains. Finally, the complete genome of P. boydii strains was obtained by sequencing, and the cluster of potential ovalicin and ovalicin biosynthesis genes was annotated. Through these metabolomic and genomic analyses, a new ovalicin derivative named boyden C, in which the 6-membered ring of ovalicin was opened by oxidative cleavage, was isolated and structurally characterized.  相似文献   
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108.
Journal of Thermal Analysis and Calorimetry - Limestone was used to modify the fluxing action of two potash feldspars (a pure potash feldspar and a soda-potash feldspar) labeled P and C,...  相似文献   
109.
Journal of Thermal Analysis and Calorimetry - A microstructural approach to the prediction of heat flux transport in porous geopolymers is used experimentally to understand the effects of the pore...  相似文献   
110.
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