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1.
Sci Rep ; 10(1): 16379, 2020 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-33009433

RESUMO

This work reports an analytical method for determining electrical resistivity (ρ) and sheet resistance (RS) of isotropic conductors. The method is compared with previous numerical solutions and available experimental data showing a universal behavior for isotropic conductors. An approximated solution is also reported allowing one to easily determine ρ and RS for samples either with regular or arbitrary shapes.

2.
Phys Chem Chem Phys ; 22(29): 16914-16925, 2020 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-32672291

RESUMO

The problem of obtaining the geometrical configuration of a molecule that minimizes its potential energy is a very complicated one for a series of applications, ranging from determining the structure of biological macromolecules to nanoclusters of atoms. Global optimization tools are available for this task, and many of them are based in performing successive local optimizations, where the starting geometries for these steps are determined by an intelligent algorithm. Here we develop a method to save computing time in the optimization of nanoclusters by predicting if a given minimum has been previously visited during local optimization steps. Our application to Cu-Al nanoalloys indicates that it is possible to save a substantial amount of computational cost. The application also reveals new promising AlxCuy clusters and explain their stabilities in terms of the jellium model.

3.
Cryo Letters ; 41(6): 365-370, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33990814

RESUMO

BACKGROUND: Semen cryopreservation is essential in animal breeding programs for improving the availability of genetic resources from animals with high breeding value. OBJECTIVE: To evaluate the addition of Brazil nut extract as a replacement for egg yolk in bovine semen cryopreservation. MATERIALS AND METHODS: Semen was collected from five Nelore bulls and cryopreserved with the addition (treatments) of 0, 25, 50, 75, or 100% Brazil nut extract in the cryoprotectant medium. After thawing, spermatic cells were evaluated for morphology, plasma membrane integrity, spermatic kinetics, and in vitro fertilization. The experimental design was in randomized blocks, and the data were submitted to regression analysis. RESULTS: The minor-type and total defects, and plasma membrane integrity were affected (P < 0.05) as a function of egg yolk substitution with Brazil nut extract. There was a significant effect (P < 0.05) of Brazil nut extract addition on the spermatic kinetics and cleavage rate. CONCLUSION: The addition of Brazil nut extract in the cryoprotective medium as a substitute of egg yolk for freezing bovine semen negatively affects sperm quality and fertility.


Assuntos
Bertholletia/química , Criopreservação/veterinária , Crioprotetores , Extratos Vegetais , Preservação do Sêmen , Animais , Bovinos , Crioprotetores/farmacologia , Gema de Ovo , Masculino , Melhoramento Vegetal , Extratos Vegetais/farmacologia , Sêmen , Análise do Sêmen , Preservação do Sêmen/veterinária , Motilidade dos Espermatozoides , Espermatozoides
4.
J Mol Model ; 24(8): 196, 2018 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-29982860

RESUMO

The DFT potential energy hypersurfaces of closed-shell nitrogen clusters up to ten atoms are explored via a genetic algorithm (GA). An atom-atom distance threshold parameter, controlled by the user, and an "operator manager" were added to the standard evolutionary procedure. Both B3LYP and PBE exchange-correlation functionals with 6-31G basis set were explored using the GA. Further evaluation of the structures generated were performed through reoptimization and vibrational analysis within MP2 and CCSD(T) levels employing larger correlation consistent basis set. The binding energies of all stable structures found are calculated and compared, as well as their energies relative to the dissociation into N2, [Formula: see text] and [Formula: see text] molecules. With the present approach, we confirmed some previously reported polynitrogen structures and predicted the stability of new ones. We can also conclude that the energy surface profile clearly depends on the calculation method employed.

5.
J Ethnopharmacol ; 179: 92-100, 2016 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-26723470

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Due to the rise in obesity, the necessity for resources and treatments that could reduce the morbidity and mortality associated to this pandemia has emerged. The development of new anti-obesity drugs through herbal sources has been increasing in the past decades which are being used not only as medicine but also as food supplements. Previous studies with the aqueous extract of Chrysobalanus icaco L (AECI) have demonstrated activity on lowering blood glucose levels and body weight. AIM OF THE STUDY: Investigate C. icaco effects in overall adiposity and glycemic homeostasis. MATERIAL AND METHODS: C57BL/6J mice were randomly assigned to standard chow (SC) or high-fat diet (HFD) and treated with AECI in 0.35mg/mL or 0.7mg/mL concentrations ad libitum. Food intake, feed efficiency, metabolic efficiency, body, fat pads and gastrocnemius weight, adiposity index, serum lipids, fecal lipid excretion, locomotor activity in the open field test and insulin and glucose tolerance tests were analyzed and compared. The major components of the extract were demonstrated through HPLC and its antioxidant activity analyzed through DPPH and lipid peroxidation. RESULTS: The AECI in the 0.35mg/mL concentration did not affect food intake or body weight. However, it promoted lower adipose tissue gain, TG levels, and fecal lipid excretion, increased locomotor activity and lean mass weight, and normalized insulin sensitivity and glucose tolerance. Moreover, AECI showed the presence of myricetin 3-O-glucuronide, rutin, quercitrin and myricitrin and demonstrated high-antioxidant activity. CONCLUSIONS: AECI in lower concentrations can prevent fat storage or enhance fat utilization through the increase of locomotor activity. Also, this reinforces its ability to maintain glucose homeostasis through the normalization of insulin sensitivity and glucose tolerance despite the high-fat diet intake. These activities could be associated to the extract's polyphenol content.


Assuntos
Fármacos Antiobesidade/uso terapêutico , Chrysobalanaceae/química , Dieta Hiperlipídica , Obesidade/tratamento farmacológico , Extratos Vegetais/uso terapêutico , Aumento de Peso/efeitos dos fármacos , Animais , Glicemia/metabolismo , Peso Corporal/efeitos dos fármacos , Sequestradores de Radicais Livres/farmacologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Atividade Motora/efeitos dos fármacos , Obesidade/patologia , Folhas de Planta/química
6.
Ceska Gynekol ; 80(4): 290-8, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26265417

RESUMO

OBJECTIVE: To evaluate the total activity performed by women with low-risk pregnancy as well as translate and pursue a cross-cultural adaptation of the Pregnancy Physical Activity Questionnaire (PPAQ) to the Brazilian reality. DESIGN: We conducted a cross-sectional quantitative study including 305 women between 16 and 40 years of age with low-risk pregnancies. SETTING: The Department of Public Health, State University of Ceará, Fortaleza, Brazil. METHODS: We applied an adapted version of PPAQ to assess the levels of physical activity and the intensity in the metabolic equivalent task (MET), which could be distinguished as follows: sedentary (< 1.5 METs), light (1.5-3.0 METs), moderate activity (3.0-6.0 METs), and vigorous activity (>6.0 METs). The Kruskal-Wallis test was used to compare energy expenditure (MET) with socio-demographic variables. RESULTS: More than half of the participants performed activities that were classified as light (51.4%). If we group the activities that were categorized as sedentary and light, this value increases to 74.7%, showing a high prevalence of insufficiently active pregnant women. Lower energy expenditure was observed in the third gestational trimester among pregnant women with lower educational level, single women, and mixed-race women (p < 0.05). CONCLUSION: There is a prevalence of physical inactivity during the three trimesters of pregnancy. The results validate PPAQ for the Brazilian population to serve as a basis for future public policies focused on combating the health problems of mother-infant pairs.


Assuntos
Cultura , Idioma , Atividade Motora , Inquéritos e Questionários , Adolescente , Adulto , Brasil , Comparação Transcultural , Estudos Transversais , Escolaridade , Metabolismo Energético , Exercício Físico , Feminino , Humanos , Gravidez , Trimestres da Gravidez , Comportamento Sedentário , Adulto Jovem
7.
In. Sala, Arnaldo; Seixas, Paulo Henrique D'Ângelo. I Mostra SES/SP 2007: experiências inovadoras na gestão da saúde no Estado de São Paulo. São Paulo, SES/SP, 2008. p.121-128, tab, graf.
Monografia em Português | LILACS, Sec. Est. Saúde SP, SESSP-CTDPROD, Sec. Est. Saúde SP | ID: lil-503599

RESUMO

Segundo a Política Nacional de Saúde do Idoso, um cuidador é "A pessoa, membro ou não da família, que, com ou sem remuneração, cuida do idoso doente ou dependente no exercício de suas atividades diárias, tais como alimentação, higiene pessoal, medicação de rotina, acompanhamento ao serviço de saúde e demais serviços requeridos no cotidiano - como a ida a bancos ou farmácias-, excluídas as técnicas ou procedimentos identificados com profissões legalmetne estabelecidas, particularmente na área de enfermagem". A família costuma ser a principal origem do cuidador e as mulheres adultas e idosas preponderam nestes cuidados. O adoecimento gera crises e momentos de desestruturação para o paciente e seus familiares. Muitas mudanças ocorrem na vida do doente, levando-o a se deparar com limitações, frustações e perdas. Essas mudanças serão definidas pelo tipo de doença, maneira que a doença se manifesta e como segue os seu curso, além do significado que o paciente e família abribuem ao evento. A família necessita se reorganizar e também se adaptar, pois o paciente pode precisar de cuidados. Os papéis e funções devem ser repensados e distribuídos de forma que auxilie o paciente na elaboração de sentimentos confusos e dolorosos ocasionados pelo processo de adoecer. Field e McGaughey apontam alguns problemas dos cuidadores tais como: pobre comunicação médica, tempo de consulta médica imprevisível, cuidado de enfermagem insuficiente e falta de conhecimento do cuidador sobre os cuidados do...


Assuntos
Idoso , Cuidadores , Saúde da Família
8.
Water Sci Technol ; 55(6): 151-6, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17486846

RESUMO

The combined biological and chemical treatments of the cellulose effluents have been studied aiming to promote a more significant degradation of their recalcitrant compounds and to reduce their toxicity, as compared with the isolated treatments. In this work the effluent from acid stages of the ECF bleaching of Eucalyptus urograndis pulp was treated by using separately activated sludge and UV radiation and its combination. The treatment efficiency was evaluated by colour, total phenol, COD, BOD, UV spectroscopy, molar weight distribution and toxicity. The untreated effluent presented 587 +/- 18 CU, 19.3 +/- 0.6 mg.L(-1) of total phenol, 2246 +/- 137 mgO2.L(-1) of COD and 904 +/- 48 mgO2.L(-1) of BOD. It did not show acute toxicity to Escherichia coli, but presented chronic toxicity to Selenastrum capricornutum (EC50 = 25%). The sludge treatment resulted in a colour increasing of 42% and decreasing of total phenol, COD and BOD of 33%, 64% and 92%, respectively. The UV radiation treatment for 120 min resulted in a decrease of colour, total phenol, BOD and COD of 70%, 43%, 62% and 43%, respectively. The combined treatment promoted an expressive decrease for colour and total phenol. The UV absorption indicated a degradation of the aromatic compounds. The biological treatment did not remove chronic toxicity and after UV radiation treatment, a 10 times improving toxicity was noticed.


Assuntos
Clorófitas/efeitos dos fármacos , Eucalyptus/química , Resíduos Industriais/efeitos adversos , Resíduos Industriais/análise , Esgotos/química , Eliminação de Resíduos Líquidos/métodos , Reatores Biológicos , Cromatografia em Gel , Corantes/análise , Concentração de Íons de Hidrogênio , Peso Molecular , Oxirredução , Papel , Fenol/análise , Espectrofotometria Ultravioleta , Fatores de Tempo , Testes de Toxicidade Crônica , Raios Ultravioleta
9.
Appl Biochem Biotechnol ; 91-93: 563-74, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11963885

RESUMO

Release of herbicides from lignin-based formulations follows a diffusion-controlled mechanism. For mathematical modeling of diffusive transport, the conventional approach is to assume sink conditions at both surfaces of polymeric matrix. This boundary condition proved to be inadequate to describe experimental data obtained in a water dynamic bath system. However, satisfactory descriptions for this system were obtained when a stagnant unstirred layer of herbicide solution was used as the boundary condition. The adequacy of the model incorporating this new boundary condition was statistically tested using the Fisher test at a confidence level of 95% and plotting the residual distribution.


Assuntos
Herbicidas/administração & dosagem , Biomassa , Biotecnologia , Preparações de Ação Retardada , Difusão , Resíduos Industriais , Cinética , Lignina/isolamento & purificação , Matemática , Modelos Teóricos , Soluções , Água
10.
Physiol Behav ; 70(1-2): 113-8, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10978485

RESUMO

For the experimental evaluation of new drugs with a potential anxiolytic effect, there are animal models that can accurately predict clinical activity. However, because of ethical factors, there are few experimental models that allow a reliable evaluation of the anxiolytic activity of drugs in studies performed with human beings. From among them, the Simulated Public Speaking and Stroop Color-Word Interference Test are notable although they are limited by the need to use subjective evaluation scales. The present study was aimed at making the determination of anxiolytic activity of drugs in normal volunteers less subjective by evaluating physiological as well as psychological alterations in subjects submitted to the anxiogenic situation of the Stroop Color-Word Interference Test. Twenty-four volunteers were submitted to the recorded version of Stroop Color-Word Interference Test, and psychological parameters (state anxiety) and physiological parameters (arterial pressure, heart rate, temperature, skin conductance, and frontal and forearm electromyograms) were evaluated before, during, and after the test. Significant differences in temperature, skin conductance and state anxiety of the volunteers were observed between the test situations. These results indicated that the Stroop Color-Word Interference Test can induce, beyond psychological alterations, some physiological alterations that could be used to make the evaluation of the anxiolytic activity of drugs more objective.


Assuntos
Ansiedade/psicologia , Testes Neuropsicológicos , Adulto , Eletromiografia , Feminino , Resposta Galvânica da Pele/fisiologia , Hemodinâmica/fisiologia , Humanos , Masculino
11.
Appl Biochem Biotechnol ; 84-86: 595-615, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10849821

RESUMO

The herbicides applied in soils can be easily lost, owing to leaching, volatilization, and bio- and photodegradation. Controlled-release systems using polymeric matrices claim to solve these problems. The movement of the herbicides in the soil is also an important phenomenon to be studied in order to evaluate the loss processes. The development of mathematical models is a relevant requirement for simulation and optimization of such systems. This study reviews mathematical models as an initial step for modeling data obtained for controlled-release systems of herbicides (diuron, 2,4-dichlorophenoxyacetic acid, and ametryn) using sugarcane bagasse lignin as a polymeric matrix. The release kinetic studies were carried out using several acceptor systems including a water bath, soil, and soil-packed columns. Generally, these models take into account phenomena such as unsteady-state mass transfer by diffusion (Fick's law) and convection, consumption by several processes, and partitioning processes, resulting in partial differential equations with respect to time and space variables.


Assuntos
Herbicidas , Lignina , Modelos Teóricos , Preparações de Ação Retardada , Estabilidade de Medicamentos , Herbicidas/química , Solo
12.
J Agric Food Chem ; 47(6): 2295-302, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10794625

RESUMO

The lignin component found in both water insoluble (WI) and water and alkali insoluble (WIA) fractions derived from SO(2)-impregnated steam-exploded eucalyptus chips (SEE) was isolated and characterized. Dioxane lignins with a sugar content lower than 2% (w/w) were obtained after each material was treated with commercial cellulases. The C9 formulas of both SEE-WI and SEE-WIA dioxane lignins were C(9)H(6.83)N(0.04)O(2.24)(OCH(3))(1.21)(OH(aro))(0.56)(OH(ali))(0. 77) and C(9)H(8.65)N(0.29)O(1.97)(OCH(3))(0.90)(OH(aro))(0. 46)(OH(ali))(1.02), respectively. The weight-average molecular weight (M(w)) of the SEE-WI lignin corresponded to 3.85 kDa, whereas the SEE-WIA lignin had an M(w) of 3.66 kDa for the same polydispersity of 2.4. The SEE-WIA lignin was shown to be more thermally stable than the SEE-WI lignin, requiring temperatures in the range of 520 degrees C for complete degradation. FTIR and (1)H NMR analyses of both untreated and peracetylated lignin fractions showed that (a) the alkali insoluble lignin contained a relatively higher degree of substitution in aromatic rings per C9 unit and that (b) alkaline extraction removed lignin fragments containing appreciable amounts of phenolic hydroxyl groups.


Assuntos
Eucalyptus , Lignina/química , Plantas Medicinais , Madeira , Celulase , Temperatura Alta , Hidrólise , Lignina/análise , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Dióxido de Enxofre
13.
Arq Bras Cardiol ; 64(6): 553-5, 1995 Jun.
Artigo em Português | MEDLINE | ID: mdl-8561676

RESUMO

PURPOSE: To study the prevalence of hypertension related on the exposition to the main risk factors. METHODS: We studied 153 students of the Medical Science Department of Taubaté University, aged between 17 to 35 years. The chosen method was the stratified simple aleatory sample. RESULTS: The prevalence of hypertension was 5.88% where all of them had one or more risk factor. A significant systolic blood pressure increase in male was found by comparing to the female. CONCLUSION: The risk factors considered alone, did not change the mean value of the hypertension, while the obesity when associated with one or more risk factors showed a considerable increase on the averages of diastolic blood pressure.


Assuntos
Hipertensão/epidemiologia , Adolescente , Adulto , Brasil , Estudos Transversais , Feminino , Humanos , Hipertensão/etiologia , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Fatores Sexuais , Estudantes de Medicina
14.
Rev Faculdade Odontol FZL ; 1(2): 97-103, 1989.
Artigo em Português | MEDLINE | ID: mdl-2485648

RESUMO

The authors examined 42 exceptional children interned in an especialized school viewing to determine the degree of gingival hyperplasia and it relation to the degree of oral hygiene, the lesion extension and the drug taken. All children were examined without verifying if they were taking any type of medicine. In the comparison of clinical exames of children taking anticonvulsants, the conclusion was that the gingival hyperplasia was present in 46.8% of the cases, as well as the extension of it being larger when the drug had been administrated for a long period and/or when oral hygiene was inadequate.


Assuntos
Hiperplasia Gengival/induzido quimicamente , Higiene Bucal , Fenitoína/administração & dosagem , Adolescente , Criança , Humanos , Fenitoína/efeitos adversos , Fatores de Tempo
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