Theoretical Study Of The Gas-phase Reaction: Sf6 + Co + → Sf5 + + Fco

Theoretical calculations using effective core potential (ECP) based methods were performed for a large number of molecular systems related to SF 6. Hartree-Fock (HF), MP2 and QCISD(T) methods were used. The quantities computed include equilibrium molecular geometries, bond dissociation energies, and adiabatic ionization energies. Where possible these quantities are compared with information available in the literature. The equilibrium geometries produced using the ECP-based methods are in very good agreement with structures reported in the literature. For the various energy differences, corresponding to the processes listed above, the ECP-based energies reproduce the trends. In addition to calculations on individual molecules, the reaction of SF6 with CO+ was studied. The first objective was to locate the reactant ion-molecule complex, the transition state, and the product ion-molecule complex for each of these systems. In this reaction neither a transition state nor a reactant ion-molecule complex could be located using HF-based forces and energies, reaction seemed to pass without a barrier to SF5 + + FCO. The use of a CASSCF(7,7)/B0 method was required to find the reactant ion-molecule complex. Finally more detailed studies were made of how the energy and charge distribution change as the reaction proceeds from reactants to products. It was observed that the reaction SF6 + CO+ → SF5 + + FCO occurs via F- abstraction, with the electronic energy barrier of 103.86 kJ mol-1. ©2008 Sociedade Brasileira de Química.1917480Kennedy, R.A., Mayhew, C.A., Thomas, R., Watts, P., (2003) Inter. J. Mass Spectrom, 223, p. 627Chim, R.Y.L., Kennedy, R.A., Tuckett, R.P., (2003) Chem. Phys. Lett, 367, p. 697Anglada, J.M., (2004) J. Am. Chem. Soc, 126, p. 9809Penteado, J.C.P., Seoud, O.A.E., Carvalho, L.R.F., (2006) Quim. Nova, 29, p. 1038SF6 Emission Reduction Partnership for Electric Power Systems, , http://www.epa.gov/highgwp/electricpower-sf6, Accessed on August 9, 2006Atterbury, C., Kennedy, R.A., Mayhew, C.A., Tuckett, R.P., (2001) Phys. Chem. Chem. Phys, 3, p. 1949Giroldo, T., Xavier, L.A., Riveros, J.M., (2004) Angew. Chem., Int. Ed, 43, p. 3588Jarvis, G.K., Kennedy, R.A., Mayhew, C.A., Tuckett, R.P., (2000) J. Phys. Chem. A, 104, p. 10766Jarvis, G.K., Kennedy, R.A., Mayhew, C.A., (2001) Int. J. Mass Spectrom, 205, p. 257Kennedy, R.A., Mayhew, C.A., (2001) Int. J. Mass Spectrom, 206, pp. AR1Chim, R.Y.L., Kennedy, R.A., Zhou, R.P.T.W.D., Collins, D.J., Hatherly, P.A., (2001) J. Phys. Chem. A, 105, p. 8403Kennedy, R.A., Mayhew, C.A., (2001) Phys. Chem. Chem. Phys, 3, p. 5511Atterbury, C., Critchley, A.D.J., Kennedy, R.A., Mayhew, C.A., Tuckett, R.P., (2002) Phys. Chem. Chem. Phys, 4, p. 2206Basta, R.B. G. Harvey, A. M. A.Ernst, R. D.J. Am. Chem. Soc. 2005, 127, 11924Custodio, R., Giordan, M., Morgon, N.H., Goddard, J.D., (1992) Int. J. Quantum Chem, 42, p. 411Custodio, R., Goddard, J.D., Giordan, M., Morgon, N.H., (1992) Can. J. Chem, 70, p. 580Morgon, N.H., (1998) J. Phys. Chem, 102, p. 2050Morgon, N.H., Argenton, A.B., Silva, M.L.P., Riveros, J.M., (1997) J. Am. Chem. Soc, 119, p. 1708Morgon, N.H., Riveros, J.M., (1998) J. Phys. Chem. A, 102, p. 10399Morgon, N.H., (2006) Int. J. Quantum Chem, 106, p. 2658Stevens, W.J., Basch, H., Kraus, M., (1984) J. Chem. Phys, 81, p. 6026Morgon, N.H., Custodio, R., Riveros, J.M., (1995) Chem. Phys. Lett, 235, p. 436Gaussian 98 Revision A.7, Frisch, M. J, Trucks, G. W, Schlegel, H. B, Scuseria, G. E, Robb, M. A, Cheeseman, J. R, Zakrzewski, V. G, Jr, J. A. M, Stratmann, R. E, Burant, J. C, Dapprich, S, Millam, J. M, Daniels, A. D, Kudin, K. N, Strain, M. C, Farkas, O, Tomasi, J, Barone, V, Cossi, M, Cammi, R, Mennucci, B, Pomelli, C, Adamo, C, Clifford, S, Ochterski, J, Petersson, G. A, Ayala, P. Y, Cui, Q, Morokuma, K, Malick, D. K, Rabuck, A. D, Raghavachari, K, Foresman, J. B, Cioslowski, J, Ortiz, J. V, Baboul, A. G, Stefanov, B. B, Liu, G, Liashenko, A, Piskorz, P, Komaromi, I, Gomperts, R, Martin, R. L, Fox, D. J, Keith, T, Al-Laham, M. A, Peng, C. Y, Nanayakkara, A, Gonzalez, C, Challacombe, M, Gill, P. M. W, Johnson, B. G, Chen, W, Wong, M. W, Andres, J. L, Head-Gordon, M, Replogle, E. S, Pople, J. A, Gaussian Inc, Pittsburgh PA, 1998Irikura, K.K., (1995) J. Chem. Phys, 102, p. 5357Bauschlicher Jr., C.W., Ricca, A., (1998) J. Phys. Chem. A, 102, p. 4722Gonzales, C., Schlegel, H.B., (1989) J. Chem. Phys, 90, p. 2154Eyring, H., (1935) J. Chem. Phys, 3, p. 107Truhlar, D.G., Hase, W.L., Hynes, J.T., (1983) J. Phys. Chem, 87, p. 2264Tsang, W., Herron, J.T., (1992) J. Chem. Phys, 96, p. 427

Poverty and disability in low- and middle-income countries: A systematic review.

INTRODUCTION: Disability and poverty are believed to operate in a cycle, with each reinforcing the other. While agreement on the existence of a link is strong, robust empirical evidence substantiating and describing this potential association is lacking. Consequently, a systematic review was undertaken to explore the relationship between disability and economic poverty, with a focus on the situation in low and middle income countries (LMICs). METHODS: Ten electronic databases were searched to retrieve studies of any epidemiological design, published between 1990-March 2016 with data comparing the level of poverty between people with and without disabilities in LMICs (World Bank classifications). Poverty was defined using economic measures (e.g. assets, income), while disability included both broad assessments (e.g. self-reported functional or activity limitations) and specific impairments/disorders. Data extracted included: measures of association between disability and poverty, population characteristics and study characteristics. Proportions of studies finding positive, negative, null or mixed associations between poverty and disability were then disaggregated by population and study characteristics. RESULTS: From the 15,500 records retrieved and screened, 150 studies were included in the final sample. Almost half of included studies were conducted in China, India or Brazil (n = 70, 47%). Most studies were cross-sectional in design (n = 124, 83%), focussed on specific impairment types (n = 115, 77%) and used income as the measure for economic poverty (n = 82, 55%). 122 studies (81%) found evidence of a positive association between disability and a poverty marker. This relationship persisted when results were disaggregated by gender, measure of poverty used and impairment types. By country income group at the time of data collection, the proportion of country-level analyses with a positive association increased with the rising income level, with 59% of low-income, 67% of lower-middle and 72% of upper-middle income countries finding a positive relationship. By age group, the proportion of studies reporting a positive association between disability and poverty was lowest for older adults and highest for working-age adults (69% vs. 86%). CONCLUSIONS: There is strong evidence for a link between disability and poverty in LMICs and an urgent need for further research and programmatic/policy action to break the cycle

Surviving polio in a post-polio world.

Excitement mounts as the global health and international development communities anticipate a polio-free world. Despite substantial political and logistical hurdles, only 223 cases of wild poliovirus in three countries were reported in 2012. Down 99% from the estimated 350,000 annual cases in 125 countries in 1988-this decline signals the imminent global eradication of polio. However, elimination of new polio cases should not also signal an end to worldwide engagement with polio. As many as 20 million continue to live with the disabling consequences of the disease. In developed countries where polio immunization became universal after dissemination of the polio vaccine in the 1950s, almost all individuals who have had polio are now above age 50. But in many developing countries where polio vaccination campaigns reached large segments of the population only after 1988, millions disabled by polio are still children or young adults. Demographically, this group is also different. After three decades of immunization efforts, those children unvaccinated in the late 1980s were more likely to be from poorer rural and slum communities and to be girls-groups not only harder to reach than more affluent members of the population but also individuals who, if they contract polio, are less likely to have access to medical and rehabilitation programs or education, job training, employment and social support services. The commitment to eradicate polio should not be considered complete while those living with the disabling sequelae of polio continue to live in poor health, poverty and social isolation. This paper reviews what is currently known about disabled survivors of polio and highlights areas of need in public health research, policy and programming. Based on a literature review, discussion and field observations, we identify continuing challenges posed by polio and argue that the attention, funding and commitment now being directed towards eradication be shifted to provide for the rehabilitative, medical, educational and social needs of those for whom the disabling sequelae of polio will remain a daily challenge for decades to come

Spurious phosphorus pyramidalization induced by some DFT functionals

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)The molecular geometries of boraphosphabenzene (BP-benzene) and boron phosphorus coronene (BP-coronene) can be misinterpreted when they are obtained from density functional theory (DFT) calculations. In this study, we found that some exchange-correlation (XC) functionals yielded a distorted geometry of the above molecules when P atoms are present in their resonance structures. This phosphorus pyramidalization may be due to spurious errors caused by using these functionals. To verify this behavior, the electronic structures of BP-benzene and BP-coronene were studied using sixteen functionals (B3LYP, B97D, BHLYP, BP96, PBE, PBE0, PWLDA, Slater-Dirac-exchange, TPSS, M05, M06, M062X, M08HX, M11, wB97 and wB97X-D) with the SVP or TZVPP basis sets. The calculations were carried out using the TURBOMOLE and GAMESS programs. The geometry optimization calculations were carried out for each functional using both of the basis sets. Two different initial geometries, plane (D-3h symmetry) and distorted (C-1 symmetry) were considered. The optimized geometries of the BP-systems obtained at the MP2/TZVPP and CC2/TZVPP levels of theory exhibited D-3h symmetry. These calculations were used as a reference and compared with those obtained from DFT. The optimized geometries obtained from DFT were found to exhibit C-1 symmetry for the majority of the XC functionals.The molecular geometries of boraphosphabenzene (BP-benzene) and boron phosphorus coronene (BP-coronene) can be misinterpreted when they are obtained from density functional theory (DFT) calculations. In this study, we found that some exchange-correlation26816481655FAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOFundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)sem informaçãosem informaçãoWe would like to acknowledge the computational facilities of the Chemistry Institute at UNICAMP as well as the financial support from Fundação de Amparo à Pesquisa de São Paulo (FAPESP) and Conselho Nacional de Desenvolvimento Científico e Tecnológico (C

Clonagem e expressão heteróloga de uma nova isoforma de metaloprotease do tipo astacina presente no veneno de aranha-marrom (Loxosceles intermedia)

Orientadora : Profª. Drª. Olga Meiri ChaimCo-orientador : Prof. Dr. Silvio Sanches VeigaDissertação (mestrado) - Universidade Federal do Paraná, Setor de Ciências Biológicas, Programa de Pós-Graduação em Biologia Celular e Molecular. Defesa: Curitiba, 26/02/2013Bibliografia : fls 136-156Resumo: O veneno das aranhas do gênero Loxosceles é composto por várias classes de moléculas biologicamente ativas com ação tóxica e/ou enzimática. Dentre estas toxinas, destacam-se serinoproteases, fosfolipases, hialuronidases e metaloproteases do tipo astacinas. As astacinas são enzimas secretadas e estão relacionadas a eventos envolvendo homeostase; ovulação e fertilização; embriogênese, como na morfogênese de tecidos; proliferação e migração celular; progressão do ciclo celular e apoptose; entre outros. Durante o envenenamento, o papel das metaloproteases no local da picada deve estar relacionado com a degradação de componentes da Matriz Extracelular, sendo então consideradas possíveis fatores de espalhamento. Por meio de estudos envolvendo biologia molecular foi possível caracterizar três isoformas de proteínas to tipo astacinas no veneno de Loxosceles intermedia, determinadas LALP1, LALP2 e LALP3. Destas, apenas a LALP1 clonada e obtida através de expressão heteróloga. Foi demonstrado que a LALP1 possui atividade sobre moléculas de matriz extracelular, como gelatina, fibrinogênio e fibronectina. Ainda, dados recentes demonstraram que as proteases do tipo astacinas constituem uma família de genes em aranhas do gênero Loxosceles e que novas isoformas podem ser encontradas. Por conseguinte, o objetivo deste trabalho foi efetuar a clonagem e expressão heteróloga de uma nova isoforma de metaloprotease presente no veneno de L. intermedia por meio de técnicas de biologia molecular, visando ainda possibilidades futuras de estudos estruturais e funcionais desta enzima. A predição da estrutura tridimensional da LALP3 revelou que a proteína possui aspectos estruturais característicos das astacinas, os quais são relevantes para a atividade destas enzimas. Os resultados obtidos da clonagem e expressão da LALP3 em vetor pET20b+ mostraram que a utilização de diferentes condições de temperatura, concentração de indutor e meio de cultura não permitiram a obtenção da proteína recombinante na condição solúvel. Desta forma, foi realizada a clonagem e expressão da LALP3 em vetor pET-SUMO, o qual permite a adição da etiqueta de solubilidade SUMO à proteína de interesse. Dentre as condições avaliadas foi verificado que as expressões utilizando as cepas de E. coli SHuffle T7 Express LysY e BL21 STAR (DE3) One Shot resultaram na proteína recombinante na condição solúvel. Após a purificação da LALP3 obtida na cepa SHuffle T7 Express LysY foram realizados testes de atividade, os quais mostraram que a LALP3 obtida não apresentou atividade sobre moléculas de fibrinogênio, azocaseína e colágeno tipo I desnaturado (gelatina). Como conclusão tem-se que os passos de purificação devem ser refinados para livrar a amostra de contaminantes e que outras estratégias podem ser utilizadas, como técnicas de refolding mais elaboradas e o emprego de sistemas de expressão utilizando organismos eucarióticos.Abstract: The venom from spiders of Loxosceles genus composed of several classes of biologically active molecules with toxic or enzymatic action. Among these toxins serinoproteases, phopholipases, hyaluronidases and astacin-like metalloproteases stand out. Astacins are secreted enzymes and are associated to events involving homeostasis; ovulation and fertilization; embryogenesis, as in tissue morphogenesis; cell migration and proliferation; cell cycle progression and apoptosis; among others. During envenomation, the role of the metalloproteases on the bite site is probably related to Extracelular Matrix degradation, being considered possible spreading factors. Through molecular biology studies it was possible to characterize three isoforms of astacin-like metalloproteases from Loxosceles intermedia, named LALP1, LALP2 and LALP3. From these, only LALP1 was cloned and obtained through heterologous expression. It was demonstrated that LALP1 is able to degrade extracellular matrix components, such gelatin, fibrinogen and fibronectin. Also, recent data showed that astacin-like proteases constitute a family of genes in spiders of Loxosceles genus and new isoforms are likely to be found. Therefore, the objective of this work was to carry out the cloning and heterologous expression of a new isoform of metalloprotease present in L. intermedia venom though molecular biology techniques, aiming for future possibilities of structural and functional studies of this protein. The three dimensional structure prediction of LALP3 revealed that the protein has structural aspects characteristic of astacins, which are important for the activity of such enzymes. The results obtained from the cloning and expression of LALP3 in pET20b+ vector depicted that different conditions of temperature, inductor concentration and culture medium did not yield the soluble protein. Therefore, the cloning and expression of LALP3 in pET-SUMO vector, which allows de addition of the solubility tag SUMO, were carried out. Among the conditions evaluated it was verified that the expressions using the E. coli strains SHuffle T7 Express LysY and BL21 STAR (DE3) One Shot yielded the soluble protein. After the purification of LALP3 obtained using the strain SHuffle T7 Express LysY activity tests were performed, which showed that LALP3 was not able to hydrolyze fibrinogen, azocasein and type I denatured collagen (gelatin) molecules. In conclusion it is stated that purification steps must be refined in order to free the sample from contaminants and other strategies can be used, as elaborated refolding techniques and the employment of expression systems using eukaryotic organisms