High-energy Auger line shapes of Pd and Rh: experiment and theory

FAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOFINEP - FINANCIADORA DE ESTUDOS E PROJETOSWe compare nonrelativistic atomic multiplet calculations of the L1,2,3M4,5M4,5 spectra of Rh and Pd in the jj intermediate-coupling scheme with high-resolution experimental spectra excited with a Ti anode, indicating general, good agreement even for these open valence shell metals: the simplicity of the calculations indicates their suitability for experimental analyses. Comparison with relativistic calculations, including configuration interaction, for Rh indicates that the nonrelativistic spectra appear to agree better with the experimental data than do the relativistic ones. The influence of relativistic and correlation effects on the intensities does not seem to be important. The major influence on the forms of the spectra is that of the relative positions of the multiplet components. Satellites of all three spectra would seem to be produced by shake-up, rather than Coster-Kronig processes. The positions and forms of these satellites are consistent with a model in which spectator vacancies in the 4d band exist in both the initial and final states of the Auger transitionWe compare nonrelativistic atomic multiplet calculations of the L1,2,3M4,5M4,5 spectra of Rh and Pd in the ii intermediate-coupling scheme with high-resolution experimental spectra excited with a Ti anode, indicating general, good agreement even for these open valence shell metals: the simplicity of the calculations indicates their suitability for experimental analyses. Comparison with relativistic calculations, including configuration interaction, for Rh indicates that the nonrelativistic spectra appear to agree better with the experimental data than do the relativistic ones. The influence of relativistic and correlation effects on the intensities does not seem to be important. The major influence on the forms of the spectra is that of the relative positions of the multiplet components. Satellites of all three spectra would seem to be produced by shake-up, rather than Coster-Kronig processes. The positions and forms of these satellites are consistent with a model in which spectator vacancies in the 4d band exist in both the initial and final states of the Auger transition. [S0163-1829(98)02548-X].58241610316109FAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOFINEP - FINANCIADORA DE ESTUDOS E PROJETOSFAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOFINEP - FINANCIADORA DE ESTUDOS E PROJETOSSem informaçãoSem informaçãoSem informaçã

Dietary nitrate supplementation enhances short but not longer duration running time-trial performance

Purpose This study evaluated the effects of dietary nitrate (NO3-) supplementation on physiological functioning and exercise performance in trained runners/ triathletes conducting short and longer distance treadmill running time-trials (TT). Method Eight trained male runners or triathletes completed four exercise performance tests comprising a 10 minute warm up followed by either a 1500 m or 10,000 m treadmill TT. Exercise performance tests were preceded 3 hours before the exercise by supplementation with either 140 ml concentrated nitrate-rich (~ 12.5 mmol nitrate) (BRJ) or nitrate-deplete (~ 0.01 mmol nitrate) (PLA) beetroot juice. Results BRJ supplementation significantly elevated plasma [NO2-] (P 0.05). However, post-exercise blood [lactate] was significantly greater in BRJ following the 1500 m TT (6.6 ± 1.2 vs. 6.1 ± 1.5 mM; P 0.05). Performance in the 1500 m TT was significantly faster in BRJ versus PLA (319.6 ± 36.2 vs. 325.7 ± 38.8 s; P 0.05). Conclusion Acute BRJ supplementation significantly enhanced 1500 m but not 10,000 m TT performance. These findings suggest that BRJ might be ergogenic during shorter-distance TTs which allow for a high work rate, but not during longer-distance TTs, completed at a lower work rate

Self-assembly Of Nitpp On Cu(111): A Transition From Disordered 1d Wires To 2d Chiral Domains.

The growth and self-assembling properties of nickel-tetraphenyl porphyrins (NiTPP) on the Cu(111) surface are analysed via scanning tunnelling microscopy (STM), X-ray photoelectron spectroscopy (XPS) and density functional theory (DFT). For low coverage, STM results show that NiTPP molecules diffuse on the terrace until they reach the step edge of the copper surface forming a 1D system with disordered orientation along the step edges. The nucleation process into a 2D superstructure was observed to occur via the interaction of molecules attached to the already nucleated 1D structure, reorienting molecules. For monolayer range coverage a 2D nearly squared self-assembled array with the emergence of chiral domains was observed. The XPS results of the Ni 2p(3/2) core levels exhibit a 2.6 eV chemical shift between the mono- and multilayer configuration of NiTPP. DFT calculations show that the observed chemical shifts of Ni 2p(3/2) occur due to the interaction of 3d orbitals of Ni with the Cu(111) substrate.1718344-1835

Dietary nitrate does not modify blood pressure and cardiac output at rest and during exercise in older adults : a randomised cross over study

Dietary nitrate (〖NO〗_3^-) supplementation has been associated with improved vascular and metabolic health. We conducted a double-blind, cross-over, placebo-controlled RCT to investigate the effects of 7-day consumption of beetroot juice compared with placebo on 1) blood pressure (BP) measured in resting conditions and during exercise, 2) cardiac and peripheral vascular function and 3) biomarkers of inflammation, oxidative stress and endothelial integrity. Twenty non-smoking healthy participants aged 60-75y and BMI 20.0-29.9kg/m2 were recruited. Measurement were conducted before and after each 7-day intervention period. Consumption of 〖NO〗_3^- had no effect on resting systolic and diastolic BP. 〖NO〗_3^- consumption did not improve indexes of central and peripheral cardiac function responses during cardiopulmonary exercise testing. Dietary 〖NO〗_3^- supplementation did not modify biomarkers of inflammation, oxidative stress and endothelial integrity. This study do not support the short-term benefits of dietary 〖NO〗_3^- supplementation on physiological and biochemical markers of vascular health in older healthy adults. Trial Registration: ISRCTN1906495

Hafnium silicide formation on Si(100) upon annealing

FAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOCAPES - COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIORHigh dielectric constant materials, such as HfO2, have been extensively studied as alternatives to SiO2 in new generations of Si based devices. Hf silicate/silicide formation has been reported in almost all literature studies of Hf based oxides on Si, using different methods of preparation. A silicate interface resembles close to the traditional Si/SiO2. The silicate very likely forms a very sharp interface between the Si substrate and the metal oxide, and would be suitable for device applications. However, the thermal instability of the interfacial silicate/oxide film leads to silicidation, causing a dramatic loss of the gate oxide integrity. Despite the importance of the Hf silicide surface and interface with Si, only a few studies of this surface are present in the literature, and a structural determination of the surface has not been reported. This paper reports a study of the Hf silicide formation upon annealing by using a combination of XPS, LEED, and x-ray photoelectron diffraction (XPD) analyses. Our results clearly indicate the formation of a unique ordered Hf silicide phase (HfSi2), which starts to crystallize when the annealing temperature is higher than 550 °C.High dielectric constant materials, such as HfO2, have been extensively studied as alternatives to SiO2 in new generations of Si based devices. Hf silicate/silicide formation has been reported in almost all literature studies of Hf based oxides on Si, using different methods of preparation. A silicate interface resembles close to the traditional Si/SiO2. The silicate very likely forms a very sharp interface between the Si substrate and the metal oxide, and would be suitable for device applications. However, the thermal instability of the interfacial silicate/oxide film leads to silicidation, causing a dramatic loss of the gate oxide integrity. Despite the importance of the Hf silicide surface and interface with Si, only a few studies of this surface are present in the literature, and a structural determination of the surface has not been reported. This paper reports a study of the Hf silicide formation upon annealing by using a combination of XPS, LEED, and x-ray photoelectron diffraction (XPD) analyses. Our results clearly indicate the formation of a unique ordered Hf silicide phase (HfSi2), which starts to crystallize when the annealing temperature is higher than 550 °C.747110FAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOCAPES - COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIORFAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOCAPES - COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIORSem informaçãoSem informação170/04This work was financially supported by DAAD (PROBRAL D/03/23553) from Germany, and FAPESP, CNPq, and CAPES (PROBRAL 170/04) from Brazil. A.S. especially would like to thank CAPES for their support

Magnetic moment of Fe3O4 films with thicknesses near the unit-cell size

CNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOFAPEMIG - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE MINAS GERAISFAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCAPES - COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIORWe perform a systematic study on the evolution of the magnetic spin moment (ms) of epitaxial [100]- and [111]-magnetite films of increasing thickness. The ultrathin films are characterized by low-energy electron diffraction, x-ray absorption spectroscopy, and x-ray magnetic circular dichroism (XMCD). By employing sum rules on the XMCD spectra we obtain ms=3.6 μB/f.u. for samples of around 35 Å. This is considered a bulk value and has been reported only for films more than 10 times thicker. Moreover, we show that even 10-Å-thick magnetite already presents a significant magnetic moment. For both grown directions the moment increases similarly with the thickness. The ferromagnetic behavior for each iron ion site (Feocta2+, Feocta3+, Fetetra3+) of Fe3O4 is measured by monitoring XMCD peaks. The deduced hysteresis curves (per ion, per site) exhibit a coercive field of 300 Oe. Our results show that both the ferrimagnetic order and the bulk moment value are preserved at room temperature around the thickness of 2 unit cells.We perform a systematic study on the evolution of the magnetic spin moment (ms) of epitaxial [100]- and [111]-magnetite films of increasing thickness. The ultrathin films are characterized by low-energy electron diffraction, x-ray absorption spectroscopy, and x-ray magnetic circular dichroism (XMCD). By employing sum rules on the XMCD spectra we obtain ms=3.6 μB/f.u. for samples of around 35 Å. This is considered a bulk value and has been reported only for films more than 10 times thicker. Moreover, we show that even 10-Å-thick magnetite already presents a significant magnetic moment. For both grown directions the moment increases similarly with the thickness. The ferromagnetic behavior for each iron ion site (Feocta2+, Feocta3+, Fetetra3+) of Fe3O4 is measured by monitoring XMCD peaks. The deduced hysteresis curves (per ion, per site) exhibit a coercive field of 300 Oe. Our results show that both the ferrimagnetic order and the bulk moment value are preserved at room temperature around the thickness of 2 unit cells.We perform a systematic study on the evolution of the magnetic spin moment (ms) of epitaxial [100]- and [111]-magnetite films of increasing thickness. The ultrathin films are characterized by low-energy electron diffraction, x-ray absorption spectroscopy, and x-ray magnetic circular dichroism (XMCD). By employing sum rules on the XMCD spectra we obtain ms=3.6 μB/f.u. for samples of around 35 Å. This is considered a bulk value and has been reported only for films more than 10 times thicker. Moreover, we show that even 10-Å-thick magnetite already presents a significant magnetic moment. For both grown directions the moment increases similarly with the thickness. The ferromagnetic behavior for each iron ion site (Feocta2+, Feocta3+, Fetetra3+) of Fe3O4 is measured by monitoring XMCD peaks. The deduced hysteresis curves (per ion, per site) exhibit a coercive field of 300 Oe. Our results show that both the ferrimagnetic order and the bulk moment value are preserved at room temperature around the thickness of 2 unit cells.901316CNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOFAPEMIG - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE MINAS GERAISFAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCAPES - COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIORCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOFAPEMIG - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE MINAS GERAISFAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCAPES - COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIORSem informaçãoSem informaçãoSem informaçãoSem informaçãoOrna, J., Algarabel, P.A., Morellón, L., Pardo, J.A., De Teresa, J.M., López Antón, R., Bartolomé, F., Wildes, A., (2010) Phys. Rev. B, 81, p. 144420. , PRBMDO 1098-0121Hari Babu, V., Govind, R.K., Schindler, K.-M., Welke, M., Denecke, R., (2013) J. Appl. Phys., 114, p. 113901. , JAPIAU 0021-8979Moussy, J.-B., Gota, S., Bataille, A., Guittet, M.-J., Gautier-Soyer, M., Delille, F., Dieny, B., Snoeck, E., (2004) Phys. Rev. B, 70, p. 174448. , PRBMDO 1098-0121Morrall, P., Schedin, F., Langridge, S., Bland, J., Thomas, M.F., Thornton, G., (2003) J. Appl. Phys., 93, p. 7960. , JAPIAU 0021-8979Liu, W.Q., Xu, Y.B., Wong, P.K.J., Maltby, N.J., Li, S.P., Wang, X.F., Du, J., Zhang, R., (2014) Appl. Phys. Lett., 104, p. 142407. , APPLAB 0003-6951Lu, Y.X., Claydon, J.S., Xu, Y.B., Schofield, D.M., Thompson, S.M., (2004) J. Appl. Phys., 95, p. 7228. , JAPIAU 0021-8979Eerenstein, W., Hibma, T., Celotto, S., (2004) Phys. Rev. B, 70, p. 184404. , PRBMDO 1098-0121Voogt, F.C., Palstra, T.T.M., Niesen, L., Rogojanu, O.C., James, M.A., Hibma, T., (1998) Phys. Rev. B, 57, p. R8107. , PRBMDO 0163-1829Monti, M., Santos, B., Mascaraque, A., Rodríguez De La Fuente, O., Niño, M.A., Mentes, T.O., Locatelli, A., De La Figuera, J., (2012) Phys. Rev. B, 85, p. 020404. , PRBMDO 1098-0121Lu, Y.X., Claydon, J.S., Xu, Y.B., Thompson, S.M., Wilson, K., Van Der Laan, G., (2004) Phys. Rev. B, 70, p. 233304. , PRBMDO 1098-0121Lu, Y.X., Claydon, J.S., Ahmad, E., Xu, Y.B., Ali, M., Hickey, B.J., Thompson, S.M., Wilson, K., (2005) J. Appl. Phys., 97, p. 10C313Schedin, F., Hewitt, L., Morrall, P., Petrov, V.N., Thornton, G., Case, S., Thomas, M.F., Uzdin, V.M., (1998) Phys. Rev. B, 58, p. R11861. , PRBMDO 0163-1829Wong, P.K.J., Zhang, W., Cui, X.G., Xu, Y.B., Wu, J., Tao, Z.K., Li, X., Van Der Laan, G., (2010) Phys. Rev. B, 81, p. 035419. , PRBMDO 1098-0121Goering, E., Gold, S., Lafkioti, M., Schütz, G., (2006) Europhys. Lett., 73, p. 97. , EULEEJ 0295-5075Chen, C.T., Idzerda, Y.U., Lin, H.-J., Smith, N.V., Meigs, G., Chaban, E., Ho, G.H., Sette, F., (1995) Phys. Rev. Lett., 75, p. 152. , PRLTAO 0031-9007Goering, E.J., Lafkioti, M., Gold, S., Schuetz, G., (2007) J. Magn. Magn. Mater., 310, p. e249. , JMMMDC 0304-8853Figueiredo, J.J.S., Basilio, R., Landers, R., Garcia, F., De Siervo, A., (2009) J. Synch. Rad., 16, p. 346. , JSYRES 0909-0495Kallmayer, M., Hild, K., Elmers, H.J., Arora, S.K., Wu, H.-C., Sofin, R.G.S., Shvets, I.V., (2008) J. Appl. Phys., 103, p. 07D715. , JAPIAU 0021-8979Huang, D.J., Chang, C.F., Jeng, H.-T., Guo, G.Y., Lin, H.-J., Wu, W.B., Ku, H.C., Chen, C.T., (2004) Phys. Rev. Lett., 93, p. 077204. , PRLTAO 0031-9007Abreu, G.J.P., Paniago, R., Pfannes, H.-D., (2014) J. Magn. Magn. Mater., 349, p. 235. , JMMMDC 0304-8853Bruns, D., Lindemann, S.R., Kuepper, K., Schemme, T., Wollschläger, J., (2013) Appl. Phys. Lett., 103, p. 052401. , APPLAB 0003-6951Fonin, M., Pentcheva, R., Dedkov, Y.S., Sperlich, M., Vyalikh, D.V., Scheffler, M., Rüdiger, U., Güntherodt, G., (2005) Phys. Rev. B, 72, p. 104436. , PRBMDO 1098-0121Ritter, M., Over, H., Weiss, W., (1997) Surf. Sci., 371, p. 245. , SUSCAS 0039-6028Ritter, M., Ranke, W., Weiss, W., (1998) Phys. Rev. B, 57, p. 7240. , PRBMDO 0163-1829Weiss, W., Ritter, M., (1999) Phys. Rev. B, 59, p. 5201. , PRBMDO 0163-1829The authors thank CNPq, FAPEMIG, FAPESP, and CAPES, Brazilian research agencies, for financial support and the Laboratorio Nacional de Luz Sincrotron for beam time (SGM-10986 and SGM-12716)

Pathophysiology of exercise intolerance in chronic diseases: the role of diminished cardiac performance in mitochondrial and heart failure patients

Objective: Exercise intolerance is a clinical hallmark of chronic conditions. The present study determined pathophysiological mechanisms of exercise intolerance in cardiovascular, neuromuscular, and metabolic disorders. Methods: In a prospective cross-sectional observational study 152 patients (heart failure reduced ejection fraction, n=32; stroke, n=34; mitochondrial disease, n=28; type two diabetes, n=28; and healthy controls, n=30) performed cardiopulmonary exercise testing with metabolic and haemodynamic measurements. Peak exercise O2 consumption and cardiac power output were measures of exercise tolerance and cardiac performance. Results: Exercise tolerance was significantly diminished in patients compared with controls (ie, by 45% stroke, 39% mitochondria disease, and 33% diabetes and heart failure, p<0.05). Cardiac performance was only significantly reduced in heart failure (due to reduced heart rate, stroke volume, and blood pressure) and mitochondrial patients (due reduced stroke volume) compared with controls (ie, by 53% and 26%, p<0.05). Ability of skeletal muscles to extract oxygen (ie, arterial-venous O2 difference) was diminished in mitochondrial, stroke, and diabetes patients (by 24%, 22%, and 18%, p<0.05), but increased by 21% in heart failure (p<0.05) compared with controls. Cardiac output explained 65% and 51% of the variance in peak O2 consumption (p<0.01) in heart failure and mitochondrial patients, whereas arterial-venous O2 difference explained 69% (p<0.01) of variance in peak O2 consumption in diabetes, and 65% and 48% in stroke and mitochondrial patients (p<0.01). Conclusions: Different mechanisms explain exercise intolerance in patients with heart failure, mitochondrial dysfunction, stroke and diabetes. Their better understanding may improve management of patients, their stress tolerance and quality of life

The association of birth order with later body mass index and blood pressure: a comparison between prospective cohort studies from the United Kingdom and Brazil

Published online 29 October 2013Previous studies have found greater adiposity and cardiovascular risk in first born children. The causality of this association is not clear. Examining the association in diverse populations may lead to improved insight.We examine the association between birth order and body mass index (BMI), systolic and diastolic blood pressure (SBP/DBP) in the 2004 Pelotas cohort from southern Brazil and the Avon Longitudinal Study of Parents and Children (ALSPAC) from Bristol, south-west England, restricting analysis to families with two children in order to remove confounding by family size.No consistent differences in BMI, SBP or DBP were observed comparing first and second born children. Within the Pelotas 2004 cohort, first born females were thinner, with lower SBP and DBP; for example, mean difference in SBP comparing first with second born was -0.979 (95% confidence interval -2.901 to 0.943). In ALSPAC, first born females had higher BMI, SBP and DBP. In both cohorts, associations tended to be in the opposite direction in males, although no statistical evidence for gender interactions was found.The findings do not support an association between birth order and BMI or blood pressure. Differences to previous studies may be explained by differences in populations and/or confounding by family size in previous studies.L D Howe, P C Hallal, A Matijasevich, J C Wells, I S Santos, A J D Barros, D A Lawlor, C G Victora and G D Smit

Nitrate-responsive oral microbiome modulates nitric oxide homeostasis and blood pressure in humans

© 2018 The Author(s) Imbalances in the oral microbial community have been associated with reduced cardiovascular and metabolic health. A possible mechanism linking the oral microbiota to health is the nitrate (NO3-)-nitrite (NO2-)-nitric oxide (NO) pathway, which relies on oral bacteria to reduce NO3- to NO2-. NO (generated from both NO2- and L-arginine) regulates vascular endothelial function and therefore blood pressure (BP). By sequencing bacterial 16S rRNA genes we examined the relationships between the oral microbiome and physiological indices of NO bioavailability and possible changes in these variables following 10 days of NO3- (12 mmol/d) and placebo supplementation in young (18–22 yrs) and old (70–79 yrs) normotensive humans (n = 18). NO3- supplementation altered the salivary microbiome compared to placebo by increasing the relative abundance of Proteobacteria (+225%) and decreasing the relative abundance of Bacteroidetes (−46%; P < 0.05). After NO3-supplementation the relative abundances of Rothia (+127%) and Neisseria (+351%) were greater, and Prevotella (−60%) and Veillonella (−65%) were lower than in the placebo condition (all P < 0.05). NO3- supplementation increased plasma concentration of NO2- and reduced systemic blood pressure in old (70–79 yrs), but not young (18–22 yrs), participants. High abundances of Rothia and Neisseria and low abundances of Prevotella and Veillonella were correlated with greater increases in plasma [NO2-] in response to NO3- supplementation. The current findings indicate that the oral microbiome is malleable to change with increased dietary intake of inorganic NO3-, and that diet-induced changes in the oral microbial community are related to indices of NO homeostasis and vascular health in vivo