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1.
J Phys Chem A ; 113(52): 14691-8, 2009 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-20028167

RESUMO

The main purpose of this paper is to report results of quantum mechanical calculation of the H(2) system using the q-Integral method with correlation corrections to the SCF (Self Consistent Field) wave functions included through the Møller-Plesset second-order perturbation (MP(2)) and Coupled-Cluster (CC) theory. Using the q-Integral method, we evaluated potential energy curves, rovibrational spectroscopy constants, rovibrational spectra, interatomic equilibrium distance and longitudinal static hyper(polarizability). All calculations were carried out through the STO-3G, STO-6G, and double-zeta (DZV) atomic basis set. The q-Integral method was implemented in the source code of the general ab initio quantum chemistry package GAMESS.

2.
J Biomater Sci Polym Ed ; 19(2): 143-60, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18237489

RESUMO

Polyelectrolyte complex (PEC) membranes were obtained by mixing solutions of two polymers of opposite charges, chitosan (Chi) and poly(acrylic acid) PAA. Three membranes were obtained: one made of pure chitosan and two membranes with chitosan mixed with PAA at a ratio of 95:5 (one prepared using PAA solution in 3.5% formic acid, named ChiPAA3.5, and another one using a PAA solution in 10% formic acid, named ChiPAA10). The membranes were characterized by swelling experiments, FT-IR spectroscopy, scanning electron microscopy (SEM), atomic force microscopy (AFM), mechanical properties and permeability studies in relation to a drug model (sodium sulphamerazine). The calculation of degree of ionization showed that the lower the formic acid concentration was, the higher the PAA dissociation degree. Polyelectrolyte complex formation was characterized by FT-IR. Water uptake results showed that PEC membranes were more hydrophilic than pure chitosan, ChiPAA3.5 being the most. Morphological analysis by SEM and AFM showed that PAA addition changed the membranes morphology, especially for ChiPAA3.5. Mechanical properties indicated that PEC membranes were more rigid than pure chitosan membranes and that the morphology has an influence on tensile strength values. Permeability values decreased with complex formation and were lower for ChiPAA10 than ChiPAA3.5. However, as drug concentration was increased, the difference between the two complex membranes disappeared. The results were discussed considering the drug-membrane interactions. Diffusion coefficient values indicated that ChiPAA3.5 had a higher drug retention capacity than ChiPAA10.


Assuntos
Resinas Acrílicas/química , Quitosana/química , Eletrólitos/química , Membranas Artificiais , Microscopia de Força Atômica , Microscopia Eletrônica de Varredura , Modelos Moleculares , Permeabilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Viscosidade , Água/química
3.
Planej Agora ; 10(249): 7-8, 1994 Jul.
Artigo em Português | MEDLINE | ID: mdl-12345909

RESUMO

PIP: On June 21, 1994, in Sao Paulo, a meeting took place of reproductive health professionals: service providers, university professors, representatives of nongovernmental organizations, secretaries of health of states and municipalities. They issued a manifesto on reproductive health in Brazil. In view of the preparations for the 3rd International Conference on Population and Development to take place in Cairo in September, 1994, it is hoped that these points will be incorporated into the official platform and in government action plans. Reproductive health is a basic human right. The growth of population decreased in Brazil in the 1980s, yet assistance in the area of reproductive health is still insufficient and unsatisfactory. The population decrease did not result in the improvement of health care and family planning. Maternal morbidity and mortality rates are still high in Brazil, especially in the north-northeastern regions, where it is 10 times higher than the national rate. There are 5 maternal deaths per 100,000 live births in Canada, 8 in the US, and 140 in Brazil. 90% of these deaths could be avoided by routine reproductive health measures. Important causes of infant mortality in Brazil are malnutrition and infectious diseases, which could be prevented by lifting the low socioeconomic level and through vaccination and birth spacing. Although fertility has been on the decline, the fertility of 10-19 year old adolescents has increased significantly, leading to high mortality rates for their infants. An estimated 1.4 million abortions occur per year in Brazil with frequent complications because of its illegal, clandestine nature. It is also estimated that 6-8 million women have been sterilized, which is the primary means of family planning because of the lack of other contraceptive options. The combination of cesarean-tubal ligation operations has been institutionalized in health services, which creates major distortions in the delivery of health care. Sexually transmitted diseases are on the rise, and HIV infections are contracted mainly from sexual intercourse and IV drug abuse. Furthermore, it is absolutely necessary for men to participate in family planning education in order to raise the status of women.^ieng


Assuntos
Aborto Induzido , Coeficiente de Natalidade , Estudos de Avaliação como Assunto , Mortalidade Infantil , Mortalidade Materna , Gravidez na Adolescência , Medicina Reprodutiva , América , Brasil , Demografia , Países em Desenvolvimento , Serviços de Planejamento Familiar , Fertilidade , Saúde , América Latina , Mortalidade , População , Dinâmica Populacional , Comportamento Sexual , América do Sul
4.
Am J Physiol ; 262(6 Pt 2): R947-54, 1992 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1621873

RESUMO

The Nagase analbuminemic rat (NAR), a mutant of the Sprague-Dawley (SD) strain, exhibits high levels of plasma cholesterol (Chol), thrombocytosis, and enhanced platelet aggregability, which might promote glomerulosclerosis (GS). To determine whether NAR are more susceptible than SD rats to aging GS, young (3-mo-old) and aging (18-mo-old) SD rats and NAR were studied. In young NAR, glomerular pressure and glomerular volume were lower, whereas total and high-density lipoprotein plasma Chol levels were higher than in young SD rats. Aging SD rats developed glomerular hypertension and hypertrophy. Less glomerular enlargement and subnormal glomerular pressures were seen in aging NAR. Enhanced platelet aggregation developed in aging SD rats, approaching the values seen in NAR. Similarly elevated levels of low-density lipoprotein Chol were seen in additional SD rats and NAR studied at 12 mo of age. Plasma triglyceride (TG) levels were lower in NAR at this age. Only SD rats developed proteinuria and exhibited GS and glomerular lipid deposits at 18 mo of age. Reduced glomerular wall stress due to lower glomerular pressure and volume as well as lower TG levels may explain the absence of GS in aging NAR despite plasma lipid and platelet abnormalities.


Assuntos
Envelhecimento/fisiologia , Glomerulosclerose Segmentar e Focal/etiologia , Albumina Sérica/análise , Animais , Colesterol/sangue , Suscetibilidade a Doenças , Taxa de Filtração Glomerular , Glomerulosclerose Segmentar e Focal/patologia , Hemodinâmica , Glomérulos Renais/patologia , Proteinúria/etiologia , Ratos , Ratos Mutantes , Triglicerídeos/sangue
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