Efeitos da idade e dos indicadores de obesidade na press��o arterial de trabalhadores

Os objetivos do estudo foram descrever a preval��ncia de hipertens��o arterial (HA) e verificar os efeitos que a idade e indicadores de obesidade provocam na press��o arterial (PA) de trabalhadores de uma ind��stria de balas e gomas. Para tanto a PA sist��lica (PAS), PA diast��lica (PAD), as medidas de massa corporal (MC), estatura e circunfer��ncia de cintura (CC) foram obtidas de 348 trabalhadores volunt��rios (243 homens e 105 mulheres). A preval��ncia de HA na amostra foi 8,9% (31 casos) e mais comum nos homens do que nas mulheres (7,2% vs 1,7%). Entre os hipertensos a idade (PAS r=0,43) e a MC (PAD r=0,39) demonstraram correla����o (r) positiva e significativa, apesar de baixa. Por sua vez entre os normotensos (317) e o grupo total (348), a idade e todos os indicadores de obesidade (MC, IMC, CC) apresentaram correla����o baixa, por��m significativa e positiva com os valores de PAS, PAD e PA m��dia (PAM) (r=0,23 a r=0,47). Adicionalmente a an��lise estat��stica revelou que homens e mulheres com HA s��o mais velhos e obesos do que seus pares normotensos. Exceto para a idade e o sexo, que s��o fatores de risco n��o modific��veis, os indicadores de obesidade possuem forte associa����o com h��bitos e comportamentos de risco e, portanto, pass��veis de preven����o.

Feeding of introduced species of Cichla (Perciformes, Cichlidae) in Volta Grande reservoir, River Grande (MG/SP)

Coordena����o de Aperfei��oamento de Pessoal de N��vel Superior (CAPES)

Diet and feeding of fish from Grande River, located below the Volta Grande Reservoir, MG-SP

Coordena����o de Aperfei��oamento de Pessoal de N��vel Superior (CAPES)

Distribui����o ecol��gica de comunidades de macroalgas de ambientes l��ticos do Parque Nacional de Itatiaia (RJ, MG), Brasil

Funda����o de Amparo �� Pesquisa do Estado de S��o Paulo (FAPESP)

Influence of iron addition on the microstructure and the electrochemical corrosion of Al-Zn-Mg alloys

The effect of Fe addition on the microstructural properties and the corrosion resistance of Al-Zn-Mg alloys submitted to different heat treatments (cast, annealed and aged), has been studied in chloride solutions using optical microscopy (OM), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray (EDX), cyclic polarization (CP) and open circuit potential (o.c.p.) measurements. The presence of 0.3% Fe in the alloy limited the growth of the MgZn2 precipitates, both in the annealed and in the quenched specimens. No effect of Cr on the grain size in the presence of Fe was found because of the accumulation of Cr in the Fe-rich particles. Fe in the Al-Zn-Mg alloys also made them more susceptible to pitting. Pitting occurred mainly near the Fe-rich particles both, under o.c.p. conditions in O-2-saturated solutions and during the CP.

Effect of precursor solution on the formation of perovskite phase of Pb(Mg-1/Nb-3(2/3))O-3 thin films

Precursor solutions for Pb(Mg1/3Nb2/3)O-3 (PMN) synthesis were obtained by Pechini's method. The influence of the concentration of organic materials on the phase formation has been studied. For this purpose, PMN solutions were prepared with different precursors and were characterized by thermogravimetric and differential thermal analysis. The obtained solutions were deposited onto a Si (100) substrate by dip coating and pre-treated in a hot plate at 300 degreesC for 1 h. The films were annealed at 600, 700, 800 and 900 degreesC for 1 h and characterized by X-ray diffraction. The perovskite phase was formed after annealing at 600 and 700 degreesC when the solution of PMN was prepared with a lower amount of organic material and starting with mobium oxide. By increasing the temperature to 800 or 900 degreesC, only the formation of pyrochlore phase was observed. With the solution prepared from mobium ethoxide, only the presence of pyrochlore phase was observed independently of the annealing temperature. (C) 2002 Elsevier B.V. B.V. All rights reserved.

Effect of welding on the microstructure and electrochemical corrosion of Al-Zn-Mg-Fe alloys

The effect of gas tungsten are welding on the microstructure and electrochemical corrosion of Al-Zn-Mg-Fe alloys submitted to different heat treatments (as fabricated, annealed and aged) has been studied using optical microscopy, SEM, TEM, EDX, cyclic voltammetry and corrosion potential measurements in chloride solutions. The electrochemical techniques were very sensitive to the change in the phase compositions produced by welding. Welding caused a decrease in the mean grain size, in the hardness and in the corrosion resistance of the age-hardened alloys. The structure of the latter became strongly altered by welding to lead to phase compositions very close to those of the cold rolled and annealed specimens. (C) 2000 Elsevier B.V. Ltd. All rights reserved.

Electrochemical behaviour of heat-treated Al-Zn-Mg alloys in chloride solutions containing sulphate

The electrochemical corrosion and passivation of Al-5Zn-1.7Mg-0.23Cu-0.053Nb alloys, submitted to different heat treatments (cold-rolled, annealed, quenched and aged, and quenched in two steps and aged), in sulphate-containing chloride solutions, has been studied by means of cyclic polarization, electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM), energy-dispersive X-ray (EDX), and X-ray photoelectron spectroscopy (XPS). The cyclic polarization curves showed that sulphate addition to the chloride solution produced a poor reproducible shift of the breakdown potential to more positive potentials. The repassivation potentials, much more reproducible, and practically separating the passive from the pitting potential region, were slightly displaced in the negative direction with that addition. When the alloys were potentiodynamically polarized in the passive potential region, sulphate was incorporated in the oxide film, thus precluding chloride ingress. In addition, Zn depletion was favoured, whereas Mg losses were avoided. Different equivalent circuits corresponding to different alloys and potentials in the passive and pitting regions were employed to account for the electrochemical processes taking place in each condition. This work shows that sulphate makes these alloys more sensitive to corrosion, increasing the fracture properties of the surface layer and favouring the pitting attack over greater areas than chloride alone. (C) 2002 Elsevier B.V. Ltd. All rights reserved.

Effect of magnesium addition on the vacancy-Mg binding free enthalpy in Al-Cr alloys

Funda����o de Amparo �� Pesquisa do Estado de S��o Paulo (FAPESP)

Fast sequential multi-element determination of Ca, Mg, K, Cu, Fe, Mn and Zn for foliar diagnosis using high-resolution continuum source flame atomic absorption spectrometry: Feasibility of secondary lines, side pixel registration and least-squares background correction

The fast sequential multi-element determination of Ca, Mg, K, Cu, Fe, Mn and Zn in plant tissues by high-resolution continuum source flame atomic absorption spectrometry is proposed. For this, the main lines for Cu (324.754 nm), Fe (248.327 nm), Mn (279.482 nm) and Zn (213.857 nm) were selected, and the secondary lines for Ca (239.856 nm), Mg (202.582 nm) and K (404.414 nm) were evaluated. The side pixel registration approach was studied to reduce sensitivity and extend the linear working range for Mg by measuring at wings (202.576 nm; 202.577 nm; 202.578 nm; 202.580 nm: 202.585 nm; 202.586 nm: 202.587 nm; 202.588 nm) of the secondary line. The interference caused by NO bands on Zn at 213.857 nm was removed using the least-squares background correction. Using the main lines for Cu, Fe, Mn and Zn, secondary lines for Ca and K, and line wing at 202.588 nm for Mg, and 5 mL min(-1) sample flow-rate, calibration curves in the 0.1-0.5 mg L-1 Cu, 0.5-4.0 mg L-1 Fe, 0.5-4.0 mg L-1 Mn, 0.2-1.0 mg L-1 Zn, 10.0-100.0 mg L-1 Ca, 5.0-40.0 mg L-1 Mg and 50.0-250.0 mg L-1 K ranges were consistently obtained. Accuracy and precision were evaluated after analysis of five plant standard reference materials. Results were in agreement at a 95% confidence level (paired t-test) with certified values. The proposed method was applied to digests of sugar-cane leaves and results were close to those obtained by line-source flame atomic absorption spectrometry. Recoveries of Ca, Mg, K, Cu, Fe, Mn and Zn in the 89-103%, 84-107%, 87-103%, 85-105%, 92-106%, 91-114%, 96-114% intervals, respectively, were obtained. The limits of detection were 0.6 mg L-1 Ca, 0.4 mg L-1 Mg, 0.4 mg L-1 K, 7.7 mu g L-1 Cu, 7.7 mu g L-1 Fe, 1.5 mu g L-1 Mn and 5.9 mu g L-1 Zn. (C) 2009 Elsevier B.V. All rights reserved.

Preparation and thermal study of Mg-diclofenac compound in solid state

Coordena����o de Aperfei��oamento de Pessoal de N��vel Superior (CAPES)

Evaluation of Ir and Pd(NO3)(2)/Mg(NO3)(2) as Modifiers for the Simultaneous Determination of Mn, Ni, Pb, and Sb in Fuel Ethanol by Graphite Furnace MS

Funda����o de Amparo �� Pesquisa do Estado de S��o Paulo (FAPESP)

Rela����o entre fisiografia e solos desenvolvidos de material cenozoico da regi��o do rio Jequitai, MG

�� estudado o relacionamento entre a fisiografia e os solos evolu��dos a partir de sedimentos cenoz��icos, de textura e composi����o vari��veis, depositados sob a a����o do rio S��o Francisco e tribut��rios. A regi��o (vale do rio Jequitai, MG) �� caracterizada por um clima sub-��mido, onde o regime de umidade do solo �� ��stico e o de temperatura isot��rmico. Foram coletados 5 pedons dispostos numa topossequ��ncia. Na posi����o mais antiga (pleistoc��nica), o solo apresenta-se em um est��gio de intensa altera����o (Typic Haplustox). Os demais solos encontram-se sobre sedimentos holoc��nicos, compondo a plan��cie aluvial do rio S��o Francisco e s��o, mineralogicamente, mais jovens, com horizonte arg��lico, representado por ultissol e molissol, ocorr��ncia esta pouco comum em situa����es de plan��cie aluvial recente. No pedon 1 (Typic Haplustox), os minerais prim��rios intemperiz��veis inexistem na fra����o grosseira. O pedon 2 (Plinthic Haplustult) apresenta na fra����o areia um acr��scimo em profundidade de minerais de f��cil altera����o. Na fra����o silte, os feldspatos j�� est��o em fase de altera����o. Os pedons 3 (Oxic Plintaquult), 4 (Fluventic Plinthustult) e 5 (Fluventic Argiustol) mostram elevadas propor����es de minerais prim��rios de f��cil altera����o (placiocl��sios calco-s��dicos, hornblenda), principalmente nas fra����es areia e silte. A ocorr��ncia destes minerais associa-se a um processo deposicional recente, aliado ��s condi����es de clima e drenagem locais.

An��lise morfom��trica da rede de drenagem da bacia do Rio do Machado-MG

Este artigo visa analisar a rede de drenagem atrav��s da utiliza����o das t��cnicas de ��ndice Rela����o Declividade e Extens��o do Curso de ��gua (RDE) e an��lise do perfil longitudinal dos vales, numa regi��o chave do Planalto Sul de Minas, a fim de contribuir com estudos sobre evolu����o da paisagem da regi��o sudeste do Brasil. A pesquisa foi realizada na Bacia Hidrogr��fica do Rio do Machado (MG), afluente do Alto Rio Grande, e regi��es adjacentes, localizadas no Planalto Sul de Minas. O Rio do Machado apresenta uma particularidade em seu curso, com uma mudan��a brusca de dire����o tomada por sua drenagem na ��rea pr��xima ao seu m��dio curso. Com a aplica����o das t��cnicas pretende-se compreender melhor a din��mica do relevo na ��rea, identificando ��reas com ind��cio de a����o neotect��nica e seu padr��o de distribui����o na bacia.