Redox conversion of cobalt(II)‐diselenide to cobalt(III)‐selenolate compounds: comparison with their sulfur analogs

The synthesis of the selenium-based ligand (LSeSeL1)-Se-1 (2,2'-diselanediylbis(N,N-bis(pyridin-2-ylmethyl)ethan-1-amine) is described along with its reactivity with cobalt(II) salts. The cobalt(II)-diselenide complex [Co-2((LSeSeL1)-Se-1)Cl-4] was obtained in good yield, and its spectroscopic properties closely resemble that of its sulfur analog. Reaction of (LSeSeL1)-Se-1 with Co(II) thiocyanate results in the formation of the cobalt(III) compound [Co((LSe)-Se-1)(NCS)(2)], similar to reaction of (LSSL1)-S-1. The redox-conversion reactions from the Co(II)-diselenide compound [Co((LSeSeL1)-Se-1)Cl-4] using external triggers such as removal of the halide ions or the addition of the strong-field ligand 8-quinolinolate resulted in good yields of the Co(III)-selenolate complexes [Co((LSe)-Se-1)(MeCN)(2)](SbF6)(2) and [Co((LSe)-Se-1)(quin)]Cl. Our computational studies show that the ligand-field splitting energy of the selenium compounds is smaller than their sulfur analogs, indicating that redox-conversion of cobalt(II)-diselenide to cobalt(III)-selenolate complexes may be more arduous than that for the related sulfur compounds.Theoretical ChemistryMetals in Catalysis, Biomimetics & Inorganic Material

Socioeconomic inequalities in dental health services in Sao Paulo, Brazil, 2003-2008

__Background:__ Access to, and use of, dental health services in Brazil have improved since 2003. The increase of private health care plans and the implementation of the "Smiling Brazil" Program, the largest public oral health care program in the world, could have influenced this increase in access. However, we do not yet know if inequalities in the use of dental health services persist after the improvement in access. The aims of this study are to analyze socioeconomic differences for dental health service use between 2003 and 2008 in São Paulo and to examine changes in these associations since the implementation of the Smiling Brazil program in 2003. __Method:__ Data was obtained via two household health surveys (ISA-Capital 2003 and ISA-Capital 2008) which investigated living conditions, lifestyle, health status and use of health care services. Logistic regression was used to analyze associations between socioeconomic factors and dental services use. Additionally, trends from 2003 to

Mudança de paradigma no ensino da Bioquímica na licenciatura em Ciências da Nutrição na Universidade do Porto

No primeiro ano da licenciatura em Ciências da Nutrição, na Faculdade de Ciências da Nutriçãoe Alimentação, da Universidade do Porto, existem duas Unidades Curriculares que introduzem aBioquímica aos estudantes [Química Orgânica e Bioquímica I (no 1º e 2º semestres,respetivamente)] e cujos programas e modalidades pedagógicas estão inter-relacionados,confrontando o estudante, progressivamente ao longo do ano letivo, com oportunidades deaprendizagem ativa.A divulgação de descobertas científicas e o envolvimento dos estudantes em projetos deinvestigação científica melhoram a aprendizagem e a retenção de conhecimentos, assim comooperacionalizam a sua aplicabilidade prática, ao mesmo tempo que desenvolvem um efeitopositivo no interesse pela investigação científica.Com o objetivo de melhorar não só a aquisição de conhecimentos, mas também a compreensão e aplicabilidade dos mesmos, assim como o desenvolvimento de competências e de raciocíniohipotético-dedutivo pelos estudantes, o ensino da Bioquímica "tradicional/clássico/base" foimodificado de modo a: 1) introduzir a discussão de artigos científicos relevantes (nas sessõesteóricas e/ou práticas); 2) possibilitar o contacto com a investigação científica feita pelosdocentes (nas sessões teóricas) e 3) possibilitar a realização de pequenos projetos deinvestigação científica (nas sessões práticas). Nestas 3 modalidades pedagógicas estãosubjacentes temas bioquímicos que integram o programa "clássico/base" das referidas UnidadesCurriculares. Adicionalmente, ao estudante são divulgados, nas 3 modalidades pedagógicasacima referidas, temas atuais da Bioquímica Nutricional ao mesmo tempo que contacta comtodas as fases da metodologia de aquisição de conhecimentos, de raciocínio e de investigaçãousadas na área da Nutrição

Strange particle production in proton-proton collisions at s=0.9\sqrt{s}=0.9 TeV with ALICE at the LHC

The production of mesons containing strange quarks (K$^0_s$, $\phi$) and both singly and doubly strange baryons ($\Lambda$, Anti-$\Lambda$, and $\Xi$+Anti-$\Xi$) are measured at central rapidity in pp collisions at $\sqrt{s}$ = 0.9 TeV with the ALICE experiment at the LHC. The results are obtained from the analysis of about 250 k minimum bias events recorded in 2009. Measurements of yields (dN/dy) and transverse momentum spectra at central rapidities for inelastic pp collisions are presented. For mesons, we report yields () of 0.184 $\pm$ 0.002 stat. $\pm$ 0.006 syst. for K$^0_s$ and 0.021 $\pm$ 0.004 stat. $\pm$ 0.003 syst. for $\phi$. For baryons, we find = 0.048 $\pm$ 0.001 stat. $\pm$ 0.004 syst. for $\Lambda$, 0.047 $\pm$ 0.002 stat. $\pm$ 0.005 syst. for Anti-$\Lambda$ and 0.0101 $\pm$ 0.0020 stat. $\pm$ 0.0009 syst. for $\Xi$+Anti-$\Xi$. The results are also compared with predictions for identified particle spectra from QCD-inspired models and provide a baseline for comparisons with both future pp measurements at higher energies and heavy-ion collisions.Comment: 33 pages, 21 captioned figures, 10 tables, authors from page 28, published version, figures at http://aliceinfo.cern.ch/ArtSubmission/node/387

Two-pion Bose-Einstein correlations in central Pb-Pb collisions at sNN\sqrt{s_{\rm NN}} = 2.76 TeV

The first measurement of two-pion Bose-Einstein correlations in central Pb-Pb collisions at $\sqrt{s_{\rm NN}} = 2.76$ TeV at the Large Hadron Collider is presented. We observe a growing trend with energy now not only for the longitudinal and the outward but also for the sideward pion source radius. The pion homogeneity volume and the decoupling time are significantly larger than those measured at RHIC.Comment: 17 pages, 5 captioned figures, 1 table, authors from page 12, published version, figures at http://aliceinfo.cern.ch/ArtSubmission/node/388

Suppression of charged particle production at large transverse momentum in central Pb-Pb collisions at sNN=2.76\sqrt{s_{\rm NN}} = 2.76 TeV

Inclusive transverse momentum spectra of primary charged particles in Pb-Pb collisions at $\sqrt{s_{_{\rm NN}}}$ = 2.76 TeV have been measured by the ALICE Collaboration at the LHC. The data are presented for central and peripheral collisions, corresponding to 0-5% and 70-80% of the hadronic Pb-Pb cross section. The measured charged particle spectra in $|\eta|<0.8$ and $0.3 < p_T < 20$ GeV/$c$ are compared to the expectation in pp collisions at the same $\sqrt{s_{\rm NN}}$, scaled by the number of underlying nucleon-nucleon collisions. The comparison is expressed in terms of the nuclear modification factor $R_{\rm AA}$. The result indicates only weak medium effects ($R_{\rm AA} \approx$ 0.7) in peripheral collisions. In central collisions, $R_{\rm AA}$ reaches a minimum of about 0.14 at $p_{\rm T}=6$-7GeV/$c$ and increases significantly at larger $p_{\rm T}$. The measured suppression of high-$p_{\rm T}$ particles is stronger than that observed at lower collision energies, indicating that a very dense medium is formed in central Pb-Pb collisions at the LHC.Comment: 15 pages, 5 captioned figures, 3 tables, authors from page 10, published version, figures at http://aliceinfo.cern.ch/ArtSubmission/node/98