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We construct a smash product operation on secondary homotopy groups yielding the structure of a lax symmetric monoidal functor.
Applications on cup-one products, Toda brackets and Whitehead products are considered.
The second author was partially supported by the Spanish Ministry of Education and Science under MEC-FEDER grants MTM2004-01865
and MTM2004-03629, the postdoctoral fellowship EX2004-0616, and a Juan de la Cierva research contract. 相似文献
74.
Since the permutation decoding algorithm is more efficient the smaller the size of the PD-set, it is important for the applications to find small PD-sets. A lower bound on the size of a PD-set is given by Gordon. There are examples for PD-sets, but up to now there is no method known to find PD-sets. The question arises whether the Gordon bound is sharp. To handle this problem we introduce the notion of antiblocking system and we show that there are examples where the Gordon bound is not sharp. 相似文献
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Clarissa Müller Tim Ortmann Akram Abi Dave Hartig Stephan Scholl Hans-Joachim Jördening 《Applied biochemistry and biotechnology》2017,182(1):197-215
Immobilization methods and carriers were screened for immobilization of Euglena gracilis extract with laminaribiose phosphorylase activity. The extract was successfully immobilized on three different carriers via covalent linkage. Suitable immobilization carriers were Sepabeads EC-EP/S and ECR 8209M with epoxy groups and ECR 8309M with amino groups as functional units. Immobilization on Sepabeads EC-EP/S resulted in highest retained activity (65%). The immobilizates were characterized for pH, temperature, and buffer molarity preferences. The immobilized enzyme lost 48% of its activity when used seven times. Together with sucrose phosphorylase, laminaribiose phosphorylase was successfully applied for bienzymatic production of laminaribiose from sucrose and glucose with a final laminaribiose concentration of 14.3 ± 2.1 g/L (20% yield). 相似文献
77.
The binding of (partial) agonists in the binding pocket of biogenic amine receptors induces a conformational change from the
inactive to the active state of the receptors. There is only little knowledge about the binding pathways of ligands into binding
pocket on molecular level. So far, it was not possible with molecular dynamic simulations to observe the ligand binding and
receptor activation. Furthermore, there is nearly nothing known, in which state of ligand binding, the receptor gets activated.
The aim of this study was to get more detailed insight into the process of ligand binding and receptor activation. With the
recently developed LigPath algorithm, we scanned the potential energy surface of the binding process of dimeric histaprodifen, a partial agonist at
the histamine H1-receptor, into the guinea pig histamine H1-receptor, taking also into account the receptor activation. The calculations exhibited large conformational changes of Trp6.48 and Phe6.55 during ligand binding and receptor activation. Additionally, conformational changes were also observed for Phe6.52, Tyr6.51 and Phe6.44. Conformational changes of Trp6.48 and Phe6.52 are discussed in literature as rotamer toggle switch in context with receptor activation. Additionally, the calculations
indicate that the binding of dimeric histaprodifen, accompanied by receptor activation is energetically preferred. In general,
this study gives new, theoretical insights onto ligand binding and receptor activation on molecular level. 相似文献
78.
Strong fluence dependence of photodesorption cross sections is observed in femtosecond laser photodesorption of NO from (NO)2 on silver nanoparticles, in contrast to femtosecond photodesorption on bulk metals. The time scale of excitation buildup is found to be equal or less than the pulse duration of ~100 fs; NO translational energies are independent of fluence and pulse duration. We propose a nanoparticle-specific nonlinear mechanism in which, due to confinement, strongly nonthermal hot-electron distributions are maintained during the femtosecond pulses, enhancing the normal desorption pathway. 相似文献
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