maigesPack: A Computational Environment for Microarray Data Analysis

Microarray technology is still an important way to assess gene expression in molecular biology, mainly because it measures expression profiles for thousands of genes simultaneously, what makes this technology a good option for some studies focused on systems biology. One of its main problem is complexity of experimental procedure, presenting several sources of variability, hindering statistical modeling. So far, there is no standard protocol for generation and evaluation of microarray data. To mitigate the analysis process this paper presents an R package, named maigesPack, that helps with data organization. Besides that, it makes data analysis process more robust, reliable and reproducible. Also, maigesPack aggregates several data analysis procedures reported in literature, for instance: cluster analysis, differential expression, supervised classifiers, relevance networks and functional classification of gene groups or gene networks

Educação ambiental e a ocupação antrópica na margem portuguesa do rio Minho : explicações de alunos do ensino secundário

A população humana pressiona o ambiente, nomeadamente, com a ocupação antrópica desregrada em zonas de risco geológico. Após pesquisa bibliográfica, sobre manifestações de ocupação antrópica e de incorrecto ordenamento do território, realizou-se um pequeno survey (levantamento). Os dados foram obtidos através da distribuição de um questionário a alunos do ensino secundário, com o intuito de diagnosticar representações e explicações sobre manifestações da ocupação antrópica na margem do rio Minho (Norte de Portugal). A análise dos questionários permitiu diagnosticar as seguintes representações: edificação em leito de cheia, exploração de recursos e poluição. As campanhas de sensibilização e a redução da poluição foram referidas como as melhores formas de optimizar a ocupação antrópica e como actividades a serem desenvolvidas no âmbito da educação ambiental

Study of the effect of pH, salinity and DOC on fluorescence of synthetic mixtures of freshwater and marine salts

In order to provide support for the discussion of the fate of organic matter in estuaries, a laboratory simulation was performed by changing freshwater ionic strength, pH and organic matter content. The change in spectroscopic characteristics caused by variations in salinity, pH and organic matter concentration in the filtered samples was observed by UV-Vis and fluorescence spectroscopy. The increase in emission fluorescence intensity of dissolved organic matter (DOM) due to increasing salinity (in the range 0 to 5 g l−1) is affected by the pH of the samples. The emission fluorescence intensity at the three maxima observed in the fluorescence spectra, is linearly correlated with dissolved organic carbon (DOC) concentration at several salinity values in the same sample. The increase in organic matter concentration caused a shift in the emission peak wavelength at 410 nm for several salinity values.We concluded that it is necessary to take into account the influence of salinity and pH on emission fluorescence of dissolved organic matter if it is to be used as a tracer in estuarine or near shore areas

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

Educação ambiental e a ocupação antrópica na margem portuguesa do rio Minho : explicações de alunos do ensino secundário

A população humana pressiona o ambiente, nomeadamente, com a ocupação antrópica desregrada em zonas de risco geológico. Após pesquisa bibliográfica, sobre manifestações de ocupação antrópica e de incorrecto ordenamento do território, realizou-se um pequeno survey (levantamento). Os dados foram obtidos através da distribuição de um questionário a alunos do ensino secundário, com o intuito de diagnosticar representações e explicações sobre manifestações da ocupação antrópica na margem do rio Minho (Norte de Portugal). A análise dos questionários permitiu diagnosticar as seguintes representações: edificação em leito de cheia, exploração de recursos e poluição. As campanhas de sensibilização e a redução da poluição foram referidas como as melhores formas de optimizar a ocupação antrópica e como actividades a serem desenvolvidas no âmbito da educação ambiental

Miniature thermoelectric power plant

This paper describes a miniature thermoelectric power plant made with the boiler and the water pump from an old starch iron. It also uses a computer cooling fan, which serves as electric power generator. The boiler vaporizes the water it receives from the water pump. Then, the steam is injected over the turbine of the fan making it twirl. The voltage generated by the fan is enough to lighten a couple of LEDs. A wooden case with a chimney encloses all the referred devices

Grand unification in the minimal left-right symmetric extension of the standard model

The simplest minimal left-right symmetric extension of the standard model is studied in the high energy limit, and some consequences of the grand unification hypothesis are explored assuming that the parity breaking scale is the only relevant energy between the electro-weak scale and the unification point. While the model is shown to be compatible with the observed neutrino phenomenology, the parity breaking scale and the heavy boson masses are predicted to be above 10^7 TeV, quite far from the reach of nowadays experiments. Below that scale only an almost sterile right handed neutrino is allowed with a mass M \approx 100 TeV

Microtubule Depolymerization Potentiates Alpha-Synuclein Oligomerization

Parkinson's disease (PD) is associated with perturbed mitochondria function and alpha-synuclein fibrillization. We evaluated potential mechanistic links between mitochondrial dysfunction and alpha-synuclein aggregation. We studied a PD cytoplasmic hybrid (cybrid) cell line in which platelet mitochondria from a PD subject were transferred to NT2 neuronal cells previously depleted of endogenous mitochondrial DNA. Compared to a control cybrid cell line, the PD line showed reduced ATP levels, an increased free/polymerized tubulin ratio, and alpha-synuclein oligomer accumulation. Taxol (which stabilizes microtubules) normalized the PD tubulin ratio and reduced alpha-synuclein oligomerization. A nexus exists between mitochondrial function, cytoskeleton homeostasis, and alpha-synuclein oligomerization. In our model, mitochondrial dysfunction triggers an increased free tubulin, which destabilizes the microtubular network and promotes alpha-synuclein oligomerization