Chemical changes of heat treated pine and eucalypt wood monitored by FTIR

A hardwood, Eucalyptus globulus Labill., and a softwood Pinus pinaster Aiton., were heat treated at temperatures between 170 and 210ºC in an oven and in an autoclave. The samples were pre-extracted with dichloromethane, ethanol and water and ground prior to Fourier Transform Infrared (FTIR) spectroscopic analysis. The heat treatment caused significant changes in the chemical composition and structure of wood, in lignin and polysaccharides. Hemicelluloses were the first to degrade as proved by the initial decrease of the 1730 cm-1 peak due to the breaking of acetyl groups in xylan. Hardwood lignin changed more than softwood lignin, with a shift of maximum absorption from 1505 cm-1 to approximately 1512 cm-1 due to decrease of methoxyl groups, loss of syringyl units or breaking of aliphatic side-chains. The macromolecular structure becomes more condensed and there is a clear increase of non-conjugated (1740 cm-1) in relation to conjugated groups (1650 cm-1). However, the changes induced by the thermal treatment are difficult to monitor by FTIR spectroscopy due to the different chemical reactions occurring simultaneously.info:eu-repo/semantics/publishedVersio

Chromium Adsorption by Modified Wood

Chromium is one of the most common heavy metals which exist in very high concentrations in wastewater. The removal is very expensive due to the high cost of normal adsorbents. Lignocellulosic materials and mainly treated materials have proven to be a good solution for this problem. Adsorption tests were performed at different pH, different times and with varying concentrations. Results show that is at pH 3 that treated wood absorbs more chromium ranging from 70% (2h treatment) to almost 100% (12 h treatment) much more than untreated wood with less than 40%. Most of the adsorption is made in the first 2-3 hours for untreated and heat treated wood. Modified wood adsorbs more chromium throughout the time. For all the samples, adsorption fitted relatively well the Langmuir model with correlation coefficient ranging from 0.85 to 0.97. The results show that heat treated wood is a good adsorbent ant that this might be a good utilization for sawdust from treating companies

Pine wood modification by heat treatment in air.

Maritime pine (Pinus pinaster) wood has low dimensional stability and durability. Heat treatment was made in an oven using hot air during 2 to 24 h and at 170-200 ºC. A comparison was made against steam heat treatment. The equilibrium moisture content and the dimensional stability (ASE) in radial and tangential directions were evaluated at 35%, 65% and 85% relative humidity. MOE, bending strength and wettability were also determined. At the same mass loss improvements of equilibrium moisture content and dimensional stability were higher for oven heat treatment but the same happened for mechanical strength degradation. A 50% decrease in hemicellulose content led to a similar decrease in bending strength

Variação transversal da composição química de árvores de Eucalyptus globulus com 15 anos de idade

Madeira de eucalipto (Eucalyptus globulus Labill.) com 15 anos de idade, da região de Águeda, foi utilizada nos ensaios. A composição química, nomeadamente extrativos em diclorometano (DCM), etanol, água e totais e lenhina insolúvel e solúvel foi determinada para a fração de 40-60 mesh. O extrato em DCM variou entre 0,24% e 0,38%, representando aproximadamente 5% dos extrativos totais. O teor de extrativos em DCM manteve-se praticamente constante no cerne, com uma ligeira diminuição a partir da medula (0,38%) até à fronteira com o borne (0,34%), e decrescendo no borne para 0,24%. Os extrativos em etanol representam mais de 50% do total e aumentam da medula para a fronteira do borne de 2,56% para 5,20%, diminuído depois no borne para 0,99%. Em relação aos extrativos em água, estes representam cerca de 45% do total e diminuem da medula para a fronteira do borne, de 3,39% para 2,18% embora sem grandes alterações nos pontos mais próximos da medula. Devido ao alto teor de extrativos solúveis em etanol os extrativos totais têm uma variação semelhante, aumentando da medula para a fronteira do borne. A percentagem de lenhina Klason aumentou da medula (19,8%) para a fronteira do borne (22,2%), aumentando ligeiramente no borne (23,0%). O teor de lenhina solúvel foi aproximadamente o mesmo para todas as amostras (aprox. 2%)info:eu-repo/semantics/publishedVersio

Amplified and Homozygously Deleted Genes in Glioblastoma: Impact on Gene Expression Levels

BACKGROUND: Glioblastoma multiforme (GBM) displays multiple amplicons and homozygous deletions that involve relevant pathogenic genes and other genes whose role remains unknown. METHODOLOGY: Single-nucleotide polymorphism (SNP)-arrays were used to determine the frequency of recurrent amplicons and homozygous deletions in GBM (n = 46), and to evaluate the impact of copy number alterations (CNA) on mRNA levels of the genes involved. PRINCIPAL FINDINGS: Recurrent amplicons were detected for chromosomes 7 (50%), 12 (22%), 1 (11%), 4 (9%), 11 (4%), and 17 (4%), whereas homozygous deletions involved chromosomes 9p21 (52%) and 10q (22%). Most genes that displayed a high correlation between DNA CNA and mRNA levels were coded in the amplified chromosomes. For some amplicons the impact of DNA CNA on mRNA expression was restricted to a single gene (e.g., EGFR at 7p11.2), while for others it involved multiple genes (e.g., 11 and 5 genes at 12q14.1-q15 and 4q12, respectively). Despite homozygous del(9p21) and del(10q23.31) included multiple genes, association between these DNA CNA and RNA expression was restricted to the MTAP gene. CONCLUSIONS: Overall, our results showed a high frequency of amplicons and homozygous deletions in GBM with variable impact on the expression of the genes involved, and they contributed to the identification of other potentially relevant genes

Desempenho pós-desmama de bovinos orgânicos suplementados em pastagens nativas do Pantanal dos Paiaguás.

Foi avaliado o desempenho pós-desmama de 309 bovinos orgânicos criados em pastagens nativas do Pantanal dos Paiaguás. Cento e dezesseis (116) novilhas e cento e vinte e um (121) novilhos foram desmamados e suplementados no período de 07/07/2003 a 30/03/2004 com ração com certificação orgânica, enquanto 36 fêmeas e 36 machos não receberam suplementação. Foram analisadas quatro pesagens durante esse período, utilizando-se modelos mistos com metodologia de estimação de máxima verossimilhança restrita (REML) em esquema multivariado de medida repetida no tempo. As novilhas e os novilhos suplementados e não suplementados pesaram 244,64 ± 29,96 kg e 234,75±15,77 kg; 275,61±40,87 kg e 259,30±22,22 kg, respectivamente. Todo efeito fixo e todas as covariáveis analisadas foram significativos (p<0,01). A suplementação fornecida aos animais proporcionou pesos que, tradicionalmente, só seriam atingidos com mais um ano de recria

Avaliação bioeconômica da suplementação de bezerros em sistema de produção orgânica no Pantanal dos Paiaguás: análise preliminar.

Utilizando-se o sistema de cocho privativo (creep feeding), foi efetuada a suplementação de bezerros orgânicos certificados durante 150 dias. O objetivo da suplementação foi o de melhorar o desempenho de bezerros pré-desmama e os índices reprodutivos das matrizes. O manejo foi realizado em duas invernadas intituladas Pirizal e Carandazal, típicas de fazendas da sub-região dos Paiaguás. A avaliação bioeconômica foi baseada nos 150 dias de suplementação. Os itens analisados em conjunto, como custos de suplementação, abrangeram os preços da ração por quilo (R$1,00); e o custo do frete por quilo (R$ 0,17). Os custos de trator; de mão-de-obra; de administração e de juros de capital foram analisados separadamente, para cada invernada

Popularização de artrópodos como instrumento de ampliação da percepção ambiental na ecologia da paisagem em agroecossistemas.

A presente obra descreve uma metodologia que pretende promover o controle biológico conservativo pela perspectiva ecossistêmica, apresentando aos participantes diversos agentes de controle biológico locais e suas relações ecológicas básicas. Considerada aqui parte essencial dessa metodologia, a leguminosa multifuncional C. argentea é apresentada como planta bioindicadora de qualidade ambiental por abrigar, nutrir e permitir a multiplicação desses organismos benéficos, além de muitas espécies de abelhas.bitstream/item/222910/1/CIT-271.pd

An analysis of protein patterns present in the saliva of diabetic patients using pairwise relationship and hierarchical clustering

Molecular diagnosis is based on the quantification of RNA, proteins, or metabolites whose concentration can be correlated to clinical situations. Usually, these molecules are not suitable for early diagnosis or to follow clinical evolution. Large-scale diagnosis using these types of molecules depends on cheap and preferably noninvasive strategies for screening. Saliva has been studied as a noninvasive, easily obtainable diagnosis fluid, and the presence of serum proteins in it enhances its use as a systemic health status monitoring tool. With a recently described automated capillary electrophoresis-based strategy that allows us to obtain a salivary total protein profile, it is possible to quantify and analyze patterns that may indicate disease presence or absence. The data of 19 persons with diabetes and 58 healthy donors obtained by capillary electrophoresis were transformed, treated, and grouped so that the structured values could be used to study individuals’ health state. After Pairwise Relationships and Hierarchical Clustering analysis were observed that amplitudes of protein peaks present in the saliva of these individuals could be used as differentiating parameters between healthy and unhealthy people. It indicates that these characteristics can serve as input for a future computational intelligence algorithm that will aid in the stratification of individuals that manifest changes in salivary proteins.info:eu-repo/semantics/acceptedVersio

Epidemic processes in complex networks

In recent years the research community has accumulated overwhelming evidence for the emergence of complex and heterogeneous connectivity patterns in a wide range of biological and sociotechnical systems. The complex properties of real-world networks have a profound impact on the behavior of equilibrium and nonequilibrium phenomena occurring in various systems, and the study of epidemic spreading is central to our understanding of the unfolding of dynamical processes in complex networks. The theoretical analysis of epidemic spreading in heterogeneous networks requires the development of novel analytical frameworks, and it has produced results of conceptual and practical relevance. A coherent and comprehensive review of the vast research activity concerning epidemic processes is presented, detailing the successful theoretical approaches as well as making their limits and assumptions clear. Physicists, mathematicians, epidemiologists, computer, and social scientists share a common interest in studying epidemic spreading and rely on similar models for the description of the diffusion of pathogens, knowledge, and innovation. For this reason, while focusing on the main results and the paradigmatic models in infectious disease modeling, the major results concerning generalized social contagion processes are also presented. Finally, the research activity at the forefront in the study of epidemic spreading in coevolving, coupled, and time-varying networks is reported.Comment: 62 pages, 15 figures, final versio