Quantitative C-13 Multicp Solid-state Nmr As A Tool For Evaluation Of Cellulose Crystallinity Index Measured Directly Inside Sugarcane Biomass

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Background: The crystallinity index (CI) is often associated with changes in cellulose structure after biological and physicochemical pretreatments. While some results obtained with lignocellulosic biomass demonstrate a progressive increase in the CI as a function of pretreatments, it is also shown that the CI can significantly vary depending on the choice of the measurement method. Besides, the influence of the CI on the recalcitrance of biomass has been controversial for a long time, but the most recent results tend to point out that the efficiency of pretreatments in reducing the recalcitrance is not clearly correlated with the decrease of the CI. Much of this controversy is somewhat associated with the inability to distinguish between the CI of the cellulose inside the biomass and the CI of the full biomass, which contains other amorphous components such as lignin and hemicellulose. Results: Cross polarization by multiple contact periods (Multi-CP) method was used to obtain quantitative C-13 solid-state nuclear magnetic resonance (ssNMR) spectra of sugarcane bagasse biomass submitted to two-step pretreatments and/or enzymatic hydrolysis. By comparing the dipolar filtered Multi-CP C-13 NMR spectra of untreated bagasse samples with those of samples submitted to acid pretreatment, we show that a 1% H2SO4-assisted pretreatment was very effective in removing practically all the hemicellulose signals. This led us to propose a spectral editing procedure based on the subtraction of MultiCP spectra of acid-treated biomass from that of the extracted lignin, to obtain a virtually pure cellulose spectrum. Based on this idea, we were able to evaluate the CI of the native cellulose inside the sugarcane bagasse biomass. Conclusions: The results show the validity of the proposed method as a tool for evaluating the variations in the CI of the cellulose inside biomasses of similar kinds. Despite a clear increase in the CI of biomass as measured by X-ray diffraction, no significant variations were observed in the CI of the cellulose inside the biomass after a particular 1% H2SO4/0.25-4% NaOH chemical-assisted pretreatments. The CI of cellulose inside the biomass solid fraction that remained after the enzymatic hydrolysis was also evaluated. The results show a slight increase in crystallinity.8Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)USP via NAP Centro de Instrumentacao para Estudos Avancados de Materiais Nanoestruturados e BiossistemasUSP via NAP de Bioenergia e SustentabilidadeEuropean Community's Seventh Framework Programme SUNLIBB (FP7) [251132]Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)CNPq [312852/2014-2, 306767/2011-2, 159341/2011 6, 482166/2010 0, 306767/2011 2, 490022/2009 0

Quantitative (13)c Multicp Solid-state Nmr As A Tool For Evaluation Of Cellulose Crystallinity Index Measured Directly Inside Sugarcane Biomass.

The crystallinity index (CI) is often associated with changes in cellulose structure after biological and physicochemical pretreatments. While some results obtained with lignocellulosic biomass demonstrate a progressive increase in the CI as a function of pretreatments, it is also shown that the CI can significantly vary depending on the choice of the measurement method. Besides, the influence of the CI on the recalcitrance of biomass has been controversial for a long time, but the most recent results tend to point out that the efficiency of pretreatments in reducing the recalcitrance is not clearly correlated with the decrease of the CI. Much of this controversy is somewhat associated with the inability to distinguish between the CI of the cellulose inside the biomass and the CI of the full biomass, which contains other amorphous components such as lignin and hemicellulose. Cross polarization by multiple contact periods (Multi-CP) method was used to obtain quantitative (13)C solid-state nuclear magnetic resonance (ssNMR) spectra of sugarcane bagasse biomass submitted to two-step pretreatments and/or enzymatic hydrolysis. By comparing the dipolar filtered Multi-CP (13)C NMR spectra of untreated bagasse samples with those of samples submitted to acid pretreatment, we show that a 1% H2SO4-assisted pretreatment was very effective in removing practically all the hemicellulose signals. This led us to propose a spectral editing procedure based on the subtraction of MultiCP spectra of acid-treated biomass from that of the extracted lignin, to obtain a virtually pure cellulose spectrum. Based on this idea, we were able to evaluate the CI of the native cellulose inside the sugarcane bagasse biomass. The results show the validity of the proposed method as a tool for evaluating the variations in the CI of the cellulose inside biomasses of similar kinds. Despite a clear increase in the CI of biomass as measured by X-ray diffraction, no significant variations were observed in the CI of the cellulose inside the biomass after a particular 1% H2SO4/0.25-4% NaOH chemical-assisted pretreatments. The CI of cellulose inside the biomass solid fraction that remained after the enzymatic hydrolysis was also evaluated. The results show a slight increase in crystallinity.811

A relação entre matemática e a pluralidade cultural associada aos direitos humanos

Este artigo tem como objetivo ressaltar a relação que a Matemática tem com diversos tópicos relacionados ao âmbito social, como pluralidade cultural, religião e direitos humanos. Busca-se denotar sua importância para a construção do indíviduo e para o desenvolvimento da sociedade, considerando o dito conhecimento oriundo dos esforços intelectuais de regiões e etnias diversas, tanto no passado quanto no presente. Palavras-chave: direitos humanos; matemática; pluralidade cultural; universalidade. Abstract This article aims to highlight the relationship that Mathematics has with various topics related to social scope, such as Cultural Plurality, Religion and Human Rights. It seeks to denote its importance for the construction of the individual and for the development of society, considering this knowledge derived from the intellectual efforts of diverse regions and ethnic groups, both past and present. Keywords: human rights; mathematics, cultural plurality, universality. &nbsp

Chemical and morphological characterization of sugarcane bagasse submitted to a delignification process for enhanced enzymatic digestibility

<p>Abstract</p> <p>Background</p> <p>In recent years, biorefining of lignocellulosic biomass to produce multi-products such as ethanol and other biomaterials has become a dynamic research area. Pretreatment technologies that fractionate sugarcane bagasse are essential for the successful use of this feedstock in ethanol production. In this paper, we investigate modifications in the morphology and chemical composition of sugarcane bagasse submitted to a two-step treatment, using diluted acid followed by a delignification process with increasing sodium hydroxide concentrations. Detailed chemical and morphological characterization of the samples after each pretreatment condition, studied by high performance liquid chromatography, solid-state nuclear magnetic resonance, diffuse reflectance Fourier transformed infrared spectroscopy and scanning electron microscopy, is reported, together with sample crystallinity and enzymatic digestibility.</p> <p>Results</p> <p>Chemical composition analysis performed on samples obtained after different pretreatment conditions showed that up to 96% and 85% of hemicellulose and lignin fractions, respectively, were removed by this two-step method when sodium hydroxide concentrations of 1% (m/v) or higher were used. The efficient lignin removal resulted in an enhanced hydrolysis yield reaching values around 100%. Considering the cellulose loss due to the pretreatment (maximum of 30%, depending on the process), the total cellulose conversion increases significantly from 22.0% (value for the untreated bagasse) to 72.4%. The delignification process, with consequent increase in the cellulose to lignin ratio, is also clearly observed by nuclear magnetic resonance and diffuse reflectance Fourier transformed infrared spectroscopy experiments. We also demonstrated that the morphological changes contributing to this remarkable improvement occur as a consequence of lignin removal from the sample. Bagasse unstructuring is favored by the loss of cohesion between neighboring cell walls, as well as by changes in the inner cell wall structure, such as damaging, hole formation and loss of mechanical resistance, facilitating liquid and enzyme access to crystalline cellulose.</p> <p>Conclusions</p> <p>The results presented herewith show the efficiency of the proposed method for improving the enzymatic digestibility of sugarcane bagasse and provide understanding of the pretreatment action mechanism. Combining the different techniques applied in this work warranted thorough information about the undergoing morphological and chemical changes and was an efficient approach to understand the morphological effects resulting from sample delignification and its influence on the enhanced hydrolysis results.</p

Estresse e depressão em docentes de uma instituição pública de ensino

Objectives: To analyze the presence of stress and signs indicative of depression in teachers of a public educational institution.Materials and Methods: An analytical study was conducted with 163 teachers from a public educational institution. The Perceived Stress Scale-EEP and Beck-IDB Depression Inventory were applied.Results: Of the 163 participants, 108 (66.3%) were males, 64 (39.3%) were between 30 and 39 years of age, 79 (48.5%) had a wage income of more than 15 wages minimum, 80 (49.1%) reported brown color. The majority had a master's degree, 84 (51.5%). Minimal levels of stress were identified in men, 73 (67.0%) and 34 (63.0%) in women. 87 (79.8%) women and 35 (64.8%) men had minimal depression. There was a significant difference in the stress and depression scores between the sexes. There was a moderate positive correlation between the scales.Conclusion: Teachers with minimal and light levels are subject to stress and depression, deserving attention from the institutions.Objetivos: Analizar la presencia de estrés y signos indicativos de depresión en docentes de una institución pública de enseñanza.Material y Métodos: Estudio analítico, realizado con 163 docentes de una institución pública de enseñanza. Se aplicó Escala de estrés percibido-EEP e inventario de depresión de Beck-IDB.Resultados: De los 163 participantes, 108 (66,3%) eran del género masculino, 64 (39,3%) con rango de edad de 30 a 39 años, 79 (48,5%) tenían una renta salarial de más de 15 salarios (en el caso de las mujeres). La mayoría presentó título de maestro, 84 (51,5%). Se identificaron niveles mínimos de estrés en hombres, 73 (67,0%) y 34 (63,0%) en mujeres. 87 (79,8%) mujeres y 35 (64,8%) hombres presentaron un nivel de depresión mínima. Hubo diferencias significativas en los escores de estrés y depresión entre los sexos. Se observó una correlación positiva moderada entre las escalas.Conclusión: Los docentes con niveles mínimo y leve están sujetos a presentar estrés y depresión, mereciendo atención por parte de las instituciones.Objetivos: Analisar a presença de estresse e sinais indicativos de depressão em docentes de uma instituição pública de ensino. Material e Métodos: Estudo analítico, realizado com 163 docentes de uma instituição pública de ensino. Aplicou-se Escala de Estresse Percebido-EEP e Inventário de Depressão de Beck-IDB. Resultados: Dos 163 participantes, 108 (66,3%) eram do gênero masculino, 64 (39,3%) com faixa etária de 30 a 39 anos, 79 (48,5%) tinham uma renda salarial de mais de 15 salários mínimos, 80 (49,1%) referiram cor parda. A maioria apresentou título de mestre, 84 (51,5%). Identificaram-se níveis mínimos de estresse em homens, 73 (67,0%) e 34 (63,0%) em mulheres. 87 (79,8%) mulheres e 35 (64,8%) homens apresentaram nível de depressão mínima. Houve diferença significativa nos escores de estresse e depressão entre os sexos. Observou-se uma correlação positiva moderada entre as escalas. Conclusão: Os docentes com níveis mínimo e leve estão sujeitos a apresentarem estresse e depressão, merecendo atenção por parte das instituições

Exercício e prevenção do diabetes mellitus: importância do modelo experimental utilizando ratos

Physical exercises have been recommended in the prevention of non-insulin dependent diabetes mellitus (NIDDM), but the mechanisms involved in this intervention are not yet fully understood. Experimental models offer the opportunity for the study of this matter. Rats administrated with STZ or alloxan in the neonatal period have been employed as models of NIDDM. In this review, we will describe the effects of exercise training on diabetes manifestation as well as metabolic aspects experimental models developed for the study of the role of exercise on diabetes prevention.O exercício tem sido recomendado na prevenção do diabetes mellitus não insulino dependente (NIDDM), mas os mecanismos envolvidos nessa intervenção ainda não são bem conhecidos. Modelos experimentais oferecem oportunidade para o estudo dessa questão. Ratos induzidos com streptozotocina e aloxana no período neonatal têm sido empregados como modelo de NIDDM. Esta revisão descreverá os efeitos do treinamento físico sobre o quadro diabético assim como aspectos metabólicos de modelos experimentais desenvolvidos para o estudo do papel do exercício na prevenção do diabetes mellitus

Efeitos do exercício físico durante a hemodiálise em indivíduos com insuficiência renal crônica: uma revisão

Main alterations seen in patients with chronic renal insufficiency are anemia, systemic arterial hypertension, and muscular atrophy, which lead to low aerobic capacity and loss of muscle strength. Hence part of these patients treatment consists in programs of physical exercise. The purpose of this literature review was to assess muscle and cardiovascular acute effects and chronic adaptations in end-stage renal disease patients submitted to physical exercise during hemodialysis. After browsing through Medline, Lilacs and PEDro databases, as well as searching for periodic articles at the UFMG Medicine School library, 13 articles were selected, related to aerobic exercise associated or not to muscle strengthening during hemodialysis. Studies varied as to exercise intensity, frequency and duration. Most articles found that physical exercise performed during hemodialysis favoured better aerobic capacity, muscle strength, and control of cardiovascular risk factors, helping solute removal during hemodialysis. Though the subject is scarcely studied, available literature shows that exercises during hemodialysis are beneficial to patients' aerobic capacity and muscle strength.As principais alterações observadas em indivíduos com insuficiência renal crônica são anemia, hipertensão arterial sistêmica e atrofia muscular, que levam à baixa capacidade aeróbica e perda de força muscular. Assim, parte do tratamento desses indivíduos consiste em programas de exercício físico. O objetivo desta revisão da literatura foi documentar os efeitos agudos e as adaptações crônicas, cardiovasculares e musculares em indivíduos no estágio final da doença renal, submetidos a programas de exercício físico durante a hemodiálise. Foram selecionados artigos científicos nas bases eletrônicas Medline, Lilacs e PEDro, assim como no acervo de periódicos da biblioteca da Faculdade de Medicina da UFMG. Foram analisados 13 artigos envolvendo exercício físico aeróbico associado ou não a fortalecimento muscular durante a hemodiálise, variando quanto à intensidade, freqüência e duração da intervenção. A maioria demonstrou que exercícios físicos realizados durante a hemodiálise promovem efeitos benéficos na melhora da capacidade aeróbica, força muscular e no controle dos fatores de risco cardiovasculares, auxiliando a remoção dos solutos durante a hemodiálise. Embora o tema seja ainda pouco explorado, a literatura disponível evidencia benefícios do exercício durante a hemodiálise sobre a capacidade aeróbica e força muscular dos pacientes

The influence of sleep deprivation and obesity on DNA damage in female Zucker rats

OBJECTIVE: The aim of this study was to evaluate overall genetic damage induced by total sleep deprivation in obese, female Zucker rats of differing ages. METHOD: Lean and obese Zucker rats at 3, 6, and 15 months old were randomly distributed into two groups for each age group: home-cage control and sleep-deprived (N = 5/group). The sleep-deprived groups were deprived sleep by gentle handling for 6 hours, whereas the home-cage control group was allowed to remain undisturbed in their home-cage. At the end of the sleep deprivation period, or after an equivalent amount of time for the home-cage control groups, the rats were brought to an adjacent room and decapitated. The blood, brain, and liver tissue were collected and stored individually to evaluate DNA damage. RESULTS: Significant genetic damage was observed only in 15-month-old rats. Genetic damage was present in the liver cells from sleep-deprived obese rats compared with lean rats in the same condition. Sleep deprivation was associated with genetic damage in brain cells regardless of obesity status. DNA damage was observed in the peripheral blood cells regardless of sleep condition or obesity status. CONCLUSION: Taken together, these results suggest that obesity was associated with genetic damage in liver cells, whereas sleep deprivation was associated with DNA damage in brain cells. These results also indicate that there is no synergistic effect of these noxious conditions on the overall level of genetic damage. In addition, the level of DNA damage was significantly higher in 15-month-old rats compared to younger rats.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Associacao Fundo de Incentivo a Pesquisa (AFIP)Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (CEPID)Universidade Federal de São Paulo (UNIFESP) Departamento de PsicobiologiaUniversidade Federal de São Paulo (UNIFESP) Departamento BiocienciaUNIFESP, Depto. de PsicobiologiaUNIFESP, Depto. Biociencia98/14303-3 e 11/12325-6 e 10/50129-1 e 07/01228-4 e 09/03360-2SciEL

Time response of increases in muscle performance after Low-Level Laser Therapy (LLLT) in weight training practitioners

Many studies have demonstrated the effectiveness of low-level laser therapy (LLLT) on muscle performance. Nonetheless, ideal application parameters are not known yet. The interval from the laser application moment until the time of the exercise is amongst them. In addition, the literature does not offer adequate studies that analyse different interval times in the same test in humans. Thus, the present study proposes the examination of the two distinct intervals, from the irradiation moment to the instant of the exercise performance. Forty male volunteers were recruited and randomly divided into four groups - control, placebo, immediate laser and 10 min after laser – to participate in this study. The therapy was performed with laser at 830 nm, with a power of 30 mW, energy of 3 J, during a time of 100 seconds per point irradiation, in the belly of the biceps brachii muscle. The comparison of the groups consisted in the Max force analysis, muscular power and muscle fatigue tests executed in the isokinetic dynamometer, and the recruitment of fibers by electromyography surface (EMG) and blood lactate levels in the brachial biceps muscle of weight training practitioners. A significant level of 5% (p &lt;0.05) was considered for data analysis. The parameters adopted in the application of LLT significantly increased muscle activity (RMS) in all protocols (peak force, power and muscular endurance). In addition, LLLT was also effective in maintaining muscle performance. It was concluded that the interval time from the moment of application of the LLLT until the performance of the exercise can influence in a different way the physical capacities tested.Many studies have demonstrated the effectiveness of low-level laser therapy (LLLT) on muscle performance. Nonetheless, ideal application parameters are not known yet. The interval from the laser application moment until the time of the exercise is amongst them. In addition, the literature does not offer adequate studies that analyse different interval times in the same test in humans. Thus, the present study proposes the examination of the two distinct intervals, from the irradiation moment to the instant of the exercise performance. Forty male volunteers were recruited and randomly divided into four groups - control, placebo, immediate laser and 10 min after laser – to participate in this study. The therapy was performed with laser at 830 nm, with a power of 30 mW, energy of 3 J, during a time of 100 seconds per point irradiation, in the belly of the biceps brachii muscle. The comparison of the groups consisted in the Max force analysis, muscular power and muscle fatigue tests executed in the isokinetic dynamometer, and the recruitment of fibers by electromyography surface (EMG) and blood lactate levels in the brachial biceps muscle of weight training practitioners. A significant level of 5% (p &lt;0.05) was considered for data analysis. The parameters adopted in the application of LLT significantly increased muscle activity (RMS) in all protocols (peak force, power and muscular endurance). In addition, LLLT was also effective in maintaining muscle performance. It was concluded that the interval time from the moment of application of the LLLT until the performance of the exercise can influence in a different way the physical capacities tested

Vagotomy diminishes obesity in cafeteria rats by decreasing cholinergic potentiation of insulin release

CAPES - COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIORHerein, we investigated whether subdiaphragmatic vagotomy has benefits on obesity, body glucose homeostasis, and insulin secretion in cafeteria (CAF)-obese rats. Wistar rats were fed a standard or CAF diet for 12 weeks. Subsequently, CAF rats were randomly submitted to truncal vagotomy (CAF Vag) or sham operation (CAF Sham). CAF Sham rats were hyperphagic, obese, and presented metabolic disturbances, including hyperinsulinemia, glucose intolerance, insulin resistance, hyperglycemia, and hypertriglyceridemia. Twelve weeks after vagotomy, CAF Vag rats presented reductions in body weight and perigonadal fat stores. Vagotomy did not modify glucose tolerance but normalized fed glycemia, insulinemia, and insulin sensitivity. Isolated islets from CAF Sham rats secreted more insulin in response to the cholinergic agent, carbachol, and when intracellular cyclic adenine monophosphate (cAMP) is enhanced by forskolin or 3-isobutyl-1-methylxanthine. Vagotomy decreased glucose-induced insulin release due to a reduction in the cholinergic action on beta-cells. This effect also normalized islet secretion in response to cAMP. Therefore, vagotomy in rats fed on a CAF-style diet effectively decreases adiposity and restores insulin sensitivity. These effects were mainly associated with the lack of cholinergic action on the endocrine pancreas, which decreases insulinemia and may gradually reduce fat storage and improve insulin sensitivity.Herein, we investigated whether subdiaphragmatic vagotomy has benefits on obesity, body glucose homeostasis, and insulin secretion in cafeteria (CAF)-obese rats. Wistar rats were fed a standard or CAF diet for 12 weeks. Subsequently, CAF rats were randomly submitted to truncal vagotomy (CAF Vag) or sham operation (CAF Sham). CAF Sham rats were hyperphagic, obese, and presented metabolic disturbances, including hyperinsulinemia, glucose intolerance, insulin resistance, hyperglycemia, and hypertriglyceridemia. Twelve weeks after vagotomy, CAF Vag rats presented reductions in body weight and perigonadal fat stores. Vagotomy did not modify glucose tolerance but normalized fed glycemia, insulinemia, and insulin sensitivity. Isolated islets from CAF Sham rats secreted more insulin in response to the cholinergic agent, carbachol, and when intracellular cyclic adenine monophosphate (cAMP) is enhanced by forskolin or 3-isobutyl-1-methylxanthine. Vagotomy decreased glucose-induced insulin release due to a reduction in the cholinergic action on beta-cells. This effect also normalized islet secretion in response to cAMP. Therefore, vagotomy in rats fed on a CAF-style diet effectively decreases adiposity and restores insulin sensitivity. These effects were mainly associated with the lack of cholinergic action on the endocrine pancreas, which decreases insulinemia and may gradually reduce fat storage and improve insulin sensitivity724625633CAPES - COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIORCAPES - COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIORsem informaçã