nent problem in the r

ing consciousness;peasant quality;tourist agriculture0山西科技Shanxi Science and Technology25-26F592.7;F323.8J149;J153;21;349;A;J;J149_349;J153_21;薛淑珍;21-22发展战略与企业管理王路; 太原高新技术产业开发区企业服务局,企业;;发展战略;;研究加入WTO以后,中国企业面临着经济国际化带来的挑战,如何在激烈竞争中占有一席之地,企业需要认真审视发展战略,以四层级战略管理进行战略能力的系统化设计和布局,尽快做大做强。Developing Strategy and Business AdministrationWang LuAfter join in WTO,Chinese enterprise is con     

Bioactivities and Mode of Actions of Dibutyl Phthalates and Nocardamine from Streptomyces sp. H11809

Dibutyl phthalate (DBP) produced by Streptomyces sp. {"type":"entrez-nucleotide","attrs":{"text":"H11809","term_id":"876629"}}H11809 exerted inhibitory activity against human GSK-3β (Hs GSK-3β) and Plasmodium falciparum 3D7 (Pf 3D7) malaria parasites. The current study aimed to determine DBP’s plausible mode of action against Hs GSK-3β and Pf 3D7. Molecular docking analysis indicated that DBP has a higher binding affinity to the substrate-binding site (pocket 2; −6.9 kcal/mol) than the ATP-binding site (pocket 1; −6.1 kcal/mol) of Hs GSK-3β. It was suggested that the esters of DBP play a pivotal role in the inhibition of Hs GSK-3β through the formation of hydrogen bonds with Arg96/Glu97 amino acid residues in pocket 2. Subsequently, an in vitro Hs GSK-3β enzymatic assay revealed that DBP inhibits the activity of Hs GSK-3β via mixed inhibition inhibitory mechanisms, with a moderate IC₅₀ of 2.0 µM. Furthermore, the decrease in K_m value with an increasing DBP concentration suggested that DBP favors binding on free Hs GSK-3β over its substrate-bound state. However, the antimalarial mode of action of DBP remains unknown since the generation of a Pf 3D7 DBP-resistant clone was not successful. Thus, the molecular target of DBP might be indispensable for Pf survival. We also identified nocardamine as another active compound from Streptomyces sp. {"type":"entrez-nucleotide","attrs":{"text":"H11809","term_id":"876629"}}H11809 chloroform extract. It showed potent antimalarial activity with an IC₅₀ of 1.5 μM, which is ~10-fold more potent than DBP, but with no effect on Hs GSK-3β. The addition of ≥12.5 µM ferric ions into the Pf culture reduced nocardamine antimalarial activity by 90% under in vitro settings. Hence, the iron-chelating ability of nocardamine was shown to starve the parasites from their iron source, eventually inhibiting their growth.     

N-Bridged Acyclic Trimeric Poly-Cyclodiphosphazanes: Highly Tuneable Cyclodiphosphazane Building Blocks

We have synthesized a completely new family of acyclic trimeric cyclodiphosphazane compounds comprising NH, NⁱPr, N^tBu and NPh bridging groups. In addition, the first NH-bridged acyclic dimeric cyclophosphazane has been produced. The trimeric species display highly tuneable characteristics so that the distance between the terminal N(H)R moieties can be readily modulated by the steric bulk present in the bridging groups (ranging from ≈6 to ≈10 Å). Moreover, these species exhibit pronounced topological changes when a weak non-bonding NH⋅⋅⋅π aryl interaction is introduced. Finally, the NH-bridged chloride binding affinities have been calculated and benchmarked along with the existing experimental data available for monomeric cyclodiphosphazanes. Our results underscore these species as promising hydrogen bond donors for supramolecular host–guest applications.     

Critical point of the two-dimensional Bose gas: An S-matrix approach

A new treatment of the critical point of the two-dimensional interacting Bose gas is presented. In the lowest order approximation we obtain the critical temperature Tc≈2πn/[mlog(2π/mg)]$T_c\approx 2\pi n/[m\log (2\pi /mg)]$, where n is the density, m the mass, and g the coupling. This result is based on a new formulation of interacting gases at finite density and temperature which is reminiscent of the thermodynamic Bethe ansatz in one dimension. In this formalism, the basic thermodynamic quantities are expressed in terms of a pseudo-energy. Consistent resummation of 2-body scattering leads to an integral equation for the pseudo-energy with a kernel based on the logarithm of the exact 2-body S-matrix.     

Synthesis and thermal decomposition of GAP-Poly(BAMO) copolymer

An energetic copolymer of glycidyl azide polymer (GAP) and poly(bis(azidomethyl)oxetane (Poly(BAMO)) was synthesized using the Borontrifluoride-dimethyl ether complex/diol initiator system. The synthesized copolymer exhibited the characteristics of an energetic thermoplastic elastomer (ETPE). Thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) were used to study the thermal decomposition behavior and the results were compared with that of the constituent homopolymers. The main weight loss step in all the polymers coincides with the exothermic dissociation of the azido groups in the side chain. In contrast with the behavior of the homopolymers, the copolymer shows a broad exothermic shoulder peak at 298 °C after the main exothermic decomposition peak at 228 °C. Kinetic analysis was performed by Vyazovkin's model-free method, which suggests that the activation energy of the main decomposition step is around 145 kJ/mol and for the second shoulder it is around 220 kJ/mol. Fourier transform infra red (FTIR) spectra of the degradation residues show that the azido groups in the copolymer decompose in two stages at different temperatures which is responsible for the double decomposition behavior.     

Synthesis,Characterization, and Crystal Structures of Various Energetic Urotropinium Salts with Azide,Nitrate, Dinitramide and Azotetrazolate Counter Ions

Urotropinium nitrate, N‐methylurotropinium azide, dinitramide and azotetrazolate salts have been prepared and fully characterized by analytical and spectoscopic (¹H, ¹³C, ¹⁴N NMR, IR, Raman) methods. The structures of all four compounds have been determined using X‐ray diffraction techniques and represent new examples of the class of high energy density materials (HEDMs).     

Fabrication of Multicomponent Polymer Nanostructures Containing PMMA Shells and Encapsulated PS Nanospheres in the Nanopores of Anodic Aluminum Oxide Templates

Multi‐component polymer nanomaterials have attracted great attention because of their applications in areas such as biomedicine, tissue engineering, and organic solar cells. The precise control over the morphologies of multi‐component polymer nanomaterials, however, is still a great challenge. In this work, the fabrication of poly(methyl methacrylate)(PMMA)/poly­styrene (PS) nanostructures that contain PMMA shells and encapsulated PS nanospheres is studied. The nanostructures are prepared using a triple solution wetting method with anodic aluminum oxide (AAO) templates. The nanopores of the templates are wetted sequentially by PS solutions in dimethylformamide (DMF), PMMA solutions in acetic acid, and water. The compositions and morphologies of the nanostructures are controlled by the interactions between the polymers, solvents, and AAO walls. This work not only presents a feasible method to prepare multi‐component polymer nanomaterials, but also leads to a better understanding of polymer‐solvent interactions in confined geometries.