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Specialized computational chemistry packages have permanently reshaped the landscape of chemical and materials science by providing tools to support and guide experimental efforts and for the prediction of atomistic and electronic properties. In this regard, electronic structure packages have played a special role by using first-principle-driven methodologies to model complex chemical and materials processes. Over the past few decades, the rapid development of computing technologies and the tremendous increase in computational power have offered a unique chance to study complex transformations using sophisticated and predictive many-body techniques that describe correlated behavior of electrons in molecular and condensed phase systems at different levels of theory. In enabling these simulations, novel parallel algorithms have been able to take advantage of computational resources to address the polynomial scaling of electronic structure methods. In this paper, we briefly review the NWChem computational chemistry suite, including its history, design principles, parallel tools, current capabilities, outreach, and outlook. [ABSTRACT FROM AUTHOR]

Consumer opinion surveys include key elements of improving the food market and assessing consumers’ approaches to current issues related to access to high-quality food. In the survey, which aimed to find out the opinions of young Polish consumers about dairy products, the focus was on issues related to the assessment of selected features of dairy products and their packaging, evaluation of regional products and innovations in dairy production. The methodology for assessing the significance of the features of dairy products and their packaging was based on the proposed feature significance index (FSI). In the carried out research, young respondents pointed to the importance of taste and quality of dairy products, and indicated the small role of packaging, determining the choice of products concerned. The ease of product identification based on packaging has gained the greatest importance among the assessed packaging features. Over two-thirds of respondents indicated that they did not pay attention to the biodegradability of dairy product packaging. When asked about regional dairy products, respondents paid most attention to their value resulting from natural methods of production without preservatives, and least to freshness. In the opinion of young consumers, access to regional products increases the certainty of using raw materials from a given region and facilitates the development of local agricultural business. A small percentage of young respondents showed knowledge of the idea of dairy production ‘from grass to glass’, which would indicate insufficient interest in innovative solutions in the dairy sector. [ABSTRACT FROM AUTHOR]

The electronic ground state of ozone and, in particular, its equilibrium geometry and harmonic vibration frequencies was studied by a variety of multiconfiguration and single-configuration methods. It is well known that the antisymmetric stretch frequency cannot be correctly obtained by single-reference methods unless at least triple excitations are included. Extensive comparison with other work in the literature shows that basis-set effects must be taken into account since the ω3 frequency is very sensitive to computational details. The multiconfiguration methods are shown to give good results provided that an adequate configuration space is used. In particular, the second-order complete active space perturbation method performs very satisfactorily. Traditional multireference configuration interaction (MRCI) methods, using a few reference functions, do not perform so well. A two-reference CI is able to give reasonable results, but only when the orbitals have been prepared by some properly correlated method. Adding several reference functions gives small improvements, and the result is capriciously dependent on the type of reference functions included. The success of the perturbation method, as well as an extreme type of MRCI, indicates that it is far more important to include a large number of diverse configurations in the reference than to treat the remaining dynamical correlation accurately. [ABSTRACT FROM AUTHOR]

Mesoporous silicas were synthesized by condensation of tetraethoxysilane (TEOS) in the presence of Pluronic P123 as a structure-forming agent, and sucrose as an auxiliary agent, to investigate the effect of sucrose and aging temperature on the final properties, particularly structure-adsorption characteristics. Obtained materials have been characterized by XRD, nitrogen sorption measurements SEM-EDX, TEM, thermogravimetry, and FT-IR. The obtained materials have well-developed porous structure-values of the specific surface area ( S) are in the range of 300-950 m/g and the sizes of primary mesopores are in the range of 9-11 nm. It was established that S and ordering significantly decreases with an increasing content of sucrose in the initial mixture. [ABSTRACT FROM AUTHOR]

Discusses bipartitie quantum systems that are described completely by a state vector and the fully deterministic Schrö equation. Analysis of thermodynamic behavior of quantum systems; Features of the model; Results of the microcanonical and canonical coupling.

Summary. Chronic infection with Hepatitis C virus (HCV) often results in cirrhosis and enhances the probability of developing hepatocellular carcinoma (HCC). The underlying mechanisms that lead to malignant transformation of infected cells, however, remain unclear. Observations made with isolated HCV antigens and/or with HCV subgenomic replicon systems demonstrated that the products encoded in the HCV genome interfere with and disturb intracellular signal transduction, often by phosphorylation of cellular proteins. Moreover, some of the HCV-encoded proteins seem to serve as substrates for host cell protein kinases. These phosphorylations affect the biological functions of the antigens. In many cases it could be demonstrated that only short stretches of the linear sequence of the viral or cellular proteins are involved and play a crucial role for these phosphorylation events. The identification of these small polypeptide elements and the subsequent development of strategies to inhibit protein–protein interactions involving them may be the first step towards reducing the chronicity and/or of the carcinogenicity of the virus. This review summarizes current knowledge of intracellular phosphorylation processes that are affected by HCV. [ABSTRACT FROM AUTHOR]

Generally, the maximum activities of the protein kinases A* (PKA) and C (PKC) show an optimum value for their substrate concentrations rather than a saturation curve; at high substrate concentrations, the kinase activity is completely abolished. The C- and N-truncated form of the non-structural protein 3 (NS3) of hepatitis C virus (HCV) (HCV-polyprotein-(1 189–1 525)) abolishes the inhibiting effect of the substrate, yielding saturable Michaelis-Menten kinetics of PKA and its catalytical domain (C subunit). In contrast, HCV-polyprotein-(1 189–1 525) activates PKC with increasing Vmax, while it abolishes the substrate inhibition of its catalytical domain (M-kinase) through a mechanism analogous to that of PKA and C subunit. PKC isoforms α, β and γ investigated are similarly activated by HCV-polyprotein-(1 189–1 525). Our data suggest that NS3 attenuates the substrate inhibition through a generalized mechanism operating mainly on the substrate level that directly results from a specific protein-protein interaction. In the case of the PKC, an additional kinase activating mechanism operates on the enzyme level. Both actions of NS3, the attenuation of the substrate inhibition and the activation of PKC, could not be explained by classical means that predict autophosphorylation to enhance the rate of substrate phosphorylation. The results are discussed in view of similar activities displayed by matchmakers and some molecular chaperones. [ABSTRACT FROM AUTHOR]

Promotion of ‘initiated’ JB6 epidermal cells to the tumor phenotype can be effected by 12--tetradecanoylphorbol-13-acetate treatment, by stimulation of epidermal growth factor (EGF) receptor activity with EGF or transforming growth factor and by exposure to the isoquinoline derivative H7. When these cells were incubated with pertussis toxin (PTX), induction of anchorage-independent growth by all four promoting substances was suppressed. The inhibition is specific since cell proliferation is not affected, suggesting that activation of a Gi protein is essential for promotion of the epidermal cells. This interpretation is strongly supported by the observation that the wasp poison mastoparan, which is known to mimic receptor-mediated activation of certain Gi proteins, also promoted anchorage independence. Immunological data and partial amino acid sequence analysis of ADP-ribosyl i isolated from PTX-treated JB6 cells indicate that a Gi-2 protein is a mediator to tumor promotion in this system. The inhibitory action of 4-bromophenacyl bromide may point to a coupling of the Gi protein to phospholipase A2. From our data we infer that promoters induce the tumor phenotype in ‘initiated’ JB6 epidermal cells by activating epigenetically the same Gi protein that in a number of adrenal and ovarian tumors appears to be persistently activated by mutational events. [ABSTRACT FROM PUBLISHER]

Synthesis and interactions of guanosine, inosine and ribavirin 5′-fluorosulfonyl-benzoyl esters with hepatitis C virus (HCV) and Flaviviruses NTPase/helicase and polymerase are described. [ABSTRACT FROM AUTHOR]