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31.
The pH-responsive nature of two self-assembled NDI-peptide amphiphile conjugates is reported. The diethoxy substituted NDI showed a pH-dependent assembly behaviour, as expected. In contrast, the isopropylamino- and ethoxy-substituted NDI based supramolecular polymer was stable at acidic and basic aqueous conditions. This finding highlights how subtle changes in the molecular design of π-stacked chromophore-peptide conjugates have a drastic impact on their equilibrium structure and ultimately functional properties.  相似文献   
32.
In this paper we prove the functoriality of the exterior square of cusp forms on as automorphic forms on and the symmetric fourth of cusp forms on as automorphic forms on . We prove these by applying a converse theorem of Cogdell and Piatetski-Shapiro to analytic properties of certain -functions obtained by the Langlands-Shahidi method. We give several applications: First, we prove the weak Ramanujan property of cuspidal representations of and the absolute convergence of the exterior square -functions of . Second, we prove that the fourth symmetric power -functions of cuspidal representations of are entire, except for those of dihedral and tetrahedral type. Third, we prove the bound for Hecke eigenvalues of Maass forms over any number field.

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33.
The interactions of epothilone analogs with the paclitaxel binding site of microtubules were studied. The influence of chemical modifications in the C15 side chain and in C12 on binding affinity and microtubule elongation was characterized. Modifications favorable for binding affinity are (1). a thiomethyl group at C21 of the thiazole side chain, (2). a methyl group at C12 in S configuration, (3). a pyridine side chain with C15 in S configuration, and (4). a cyclopropyl moiety between C12 and C13. The same modification in different ligands has similar effect on affinity, allowing good structure-affinity characterization. The correlation between binding, microtubule stabilization, and cytotoxicity of the compounds has been determined, showing differential effects of the modifications. The binding constants correlate well with IC(50) values, demonstrating that affinity measurements are a useful tool for drug design.  相似文献   
34.
Fuels derived from biomass are renewable as well as environment friendly. In this study, three biomasses viz. husk of areca nut (Areca catheu), trunks of moj (Albizzia lucida), and bon bogori (Ziziphus rugosus) available in North-East region of India were tested as potential biofuel sources. The accentuation of this study was to determine the kinetic parameters using thermogravimetric (TG) technique under air and nitrogen atmosphere. The experiments were carried out within temperature range 300–973 K under air and nitrogen atmosphere at four different heating rates viz. 5, 10, 15, and 20 K min?1, respectively. The mass losses at different lumps in the TG graphs were estimated. The first-order kinetic parameters such as activation energy and pre-exponential factor were calculated for different reaction zones for all the three biomass samples. Effects of atmosphere on combustion characteristics (e.g., peak temperature, ignition temperature, and reactivity index) of biomasses were also determined in this study. Areca nut husk has highest ignition temperature (526.38 K) and reactivity index (0.21) but moj has highest peak temperature (597.91 K) along with highest activation energy (348.04 kJ mol?1) and pre-exponential factor (1.12 × 1024 min?1), respectively.  相似文献   
35.
We update and complete the proof of Proposition 7 in Van Vyve and Ortega (2004) [1], which states that the projection of a facility location reformulation of an uncapacitated lot-sizing problem with fixed charges on stocks (ULSW) to the original space is equivalent to that of the tight shortest path reformulation of ULSW. Their proof is interesting and consists of two cases, only first of which is analyzed in detail. We show that the second case exhibits several challenges not present in the first one and necessitates an updated proof.  相似文献   
36.
Structure and dynamics of acrylodan labeled αA-crystallin tetramer formed in the presence of a bile salt (sodium deoxycholate, NaDC) has been studied using fluorescence correlation spectroscopy (FCS) and femtosecond up-conversion techniques. Using FCS it is shown that, the diffusion constant (D(t)) of the αA-crystallin oligomer (mass ~800 kDa) increases from ~35 μm(2) s(-1) to ~68 μm(2) s(-1). This corresponds to a decrease in hydrodynamic radius (r(h)) from ~6.9 nm to ~3.3 nm. This corresponds to about 10-fold decrease in molecular mass to ~80 kDa and suggests formation of a tetramer (since mass of αA-crystallin monomer is ~20 kDa). The steady state emission maximum and average solvation time (<τ(s)>) of acrylodan labeled at cysteine 131 position of αA-crystallin is markedly affected on addition of NaDC, while the tryptophan (trp-9) becomes more exposed. This suggests that NaDC binds near the cys-131 and makes the terminal region of αA-crystallin exposed. This may explain the enhanced auto-phosphorylation activity of αA-crystallin near the terminus of the 173 amino acid protein (e.g., at the threonine 13, serine 45, or serine 169 and 172) and suggests that phosphorylation at ser-122 (close to cys-131) is relatively less important.  相似文献   
37.
O‐Mannose glycans account up to 30 % of total O‐glycans in the brain. Previous synthesis and functional studies have only focused on the core M3 O‐mannose glycans of α‐dystroglycan, which are a causative factor for various muscular diseases. In this study, a highly efficient chemoenzymatic strategy was developed that enabled the first collective synthesis of 63 core M1 and core M2 O‐mannose glycans. This chemoenzymatic strategy features the gram‐scale chemical synthesis of five judiciously designed core structures, and the diversity‐oriented modification of the core structures with three enzyme modules to provide 58 complex O‐mannose glycans in a linear sequence that does not exceed four steps. The binding profiles of synthetic O‐mannose glycans with a panel of lectins, antibodies, and brain proteins were also explored by using a printed O‐mannose glycan array.  相似文献   
38.
We consider quantum steering by non-Gausssian entangled states. The Reid steering criterion based on the Heisenberg uncertainty relation fails to detect steerability for many categories of such states. Here, we derive a tighter steering criterion using the Robertson–Schrödinger uncertainty relation. We show that our steering condition is able to detect steerability of several classes of non-Gaussian states such as entangled eigenstates of the two-dimensional harmonic oscillator, the photon subtracted squeezed vacuum state and the NOON state.  相似文献   
39.
Journal of Thermal Analysis and Calorimetry - In this work, a detailed numerical investigation has been carried out to study the forced convection heat transfer from an inclined elliptic cylinder...  相似文献   
40.
The paper explores an eco‐epidemiological model of a predator–prey type, where the prey population is subject to infection. The model is basically a combination of S‐I type model and a Rosenzweig–MacArthur predator–prey model. The novelty of this contribution is to consider different competition coefficients within the prey population, which leads to the emergent carrying capacity. We explicitly separate the competition between non‐infected and infected individuals. This emergent carrying capacity is markedly different to the explicit carrying capacities that have been considered in many eco‐epidemiological models. We observed that different intra‐class and inter‐class competition can facilitate the coexistence of susceptible prey‐infected prey–predator, which is impossible for the case of the explicit carrying capacity model. We also show that these findings are closely associated with bi‐stability. The present system undergoes bi‐stability in two different scenarios: (a) bi‐stability between the planner equilibria where susceptible prey co‐exists with predator or infected prey and (b) bi‐stability between co‐existence equilibrium and the planner equilibrium where susceptible prey coexists with infected prey; have been discussed. The conditions for which the system is to be permanent and the global stability of the system around disease‐free equilibrium are worked out. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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