Thermal modification and alkyl ketene dimer effects on the surface protection of deodar cedar (Cedrus deodara Roxb.) wood

The aim of this research was to evaluate the multiple effects of both thermal modification and alkyl ketene dimer (AKD) on the deodar cedar (Cedrus deodara Roxb.) wood surface, before and after an irradiation test. The physical and chemical changes that occurred on the cedar wood samples due to the combined effect of these modifications were evaluated by measuring their wettability and colour and using attenuated total reflection Fourier-transform infrared spectroscopy (ATR-FTIR) and X-ray photoelectron spectroscopy (XPS) analyses. The surface analysis by XPS showed the expected variability among the sampled layers for unmodified and thermally modified cedar wood samples and a uniform composition after the AKD coverage, regardless of their pre-treatments. The FTIR spectra before the irradiation test showed that the hydrophobicity of the samples was ensured by the formation of carbonyl groups originating from the reaction between the AKD and hydroxyl groups of cellulose, which is related to the presence of the absorption band between 1700 cm−1 and 1750 cm−1. Markedly, after the irradiation test, a degradation of the amorphous cellulose component occurred, showing that photoisomerisation to the enolic form took place. Overall, although uniform AKD coverage was derived from the surface analysis and wetting test, the combined ATR-FTIR results and colour measurements showed that it could not provide permanent protection to the underlying wood structure due to its own tendency to degrade mainly in colour over time, under the action of UV rays and atmospheric agents

Visualizing Contextual and Dynamic Features of Micropost Streams

Visual techniques provide an intuitive way of making sense of the large amounts of microposts available from social media sources, particularly in the case of emerging topics of interest to a global audience, which often raise controversy among key stakeholders. Micropost streams are context-dependent and highly dynamic in nature. We describe a visual analytics platform to handle high-volume micropost streams from multiple social media channels. For each post we extract key contextual features such as location, topic and sentiment, and subsequently render the resulting multi-dimensional information space using a suite of coordinated views that support a variety of complex information seeking behaviors. We also describe three new visualization techniques that extend the original platform to account for the dynamic nature of micro¬post streams through dynamic topography information landscapes, news flow diagrams and longitudinal cross-media analyses

Loss of BRCA1 or BRCA2 markedly increases the rate of base substitution mutagenesis and has distinct effects on genomic deletions

Loss-of-function mutations in the BRCA1 and BRCA2 genes increase the risk of cancer. Owing to their function in homologous recombination repair, much research has focused on the unstable genomic phenotype of BRCA1/2 mutant cells manifest mainly as large-scale rearrangements. We used whole-genome sequencing of multiple isogenic chicken DT40 cell clones to precisely determine the consequences of BRCA1/2 loss on all types of genomic mutagenesis. Spontaneous base substitution mutation rates increased sevenfold upon the disruption of either BRCA1 or BRCA2, and the arising mutation spectra showed strong and specific correlation with a mutation signature associated with BRCA1/2 mutant tumours. To model endogenous alkylating damage, we determined the mutation spectrum caused by methyl methanesulfonate (MMS), and showed that MMS also induces more base substitution mutations in BRCA1/2-deficient cells. Spontaneously arising and MMS-induced insertion/deletion mutations and large rearrangements were also more common in BRCA1/2 mutant cells compared with the wild-type control. A difference in the short deletion phenotypes of BRCA1 and BRCA2 suggested distinct roles for the two proteins in the processing of DNA lesions, as BRCA2 mutants contained more short deletions, with a wider size distribution, which frequently showed microhomology near the breakpoints resembling repair by non-homologous end joining. An increased and prolonged gamma-H2AX signal in MMS-treated BRCA1/2 cells suggested an aberrant processing of stalled replication forks as the cause of increased mutagenesis. The high rate of base substitution mutagenesis demonstrated by our experiments is likely to significantly contribute to the oncogenic effect of the inactivation of BRCA1 or BRCA2.Oncogene advance online publication, 25 July 2016; doi:10.1038/onc.2016.243. © 2016 The Author(s

Intra-annual patterns of tracheid size in the Mediterranean tree Juniperus thurifera as an indicator of seasonal water stress

Because climate can affect xylem cell anatomy, series of intra-annual cell anatomical features have the potential to retrospectively supply seasonal climatic information. In this study, we explored the ability to extract information about water stress conditions from tracheid features of the Mediterranean conifer Juniperus thurifera L. Tracheidograms of four climatic years from two drought-sensitive sites in Spain were compared to evaluate whether it is possible to link intra-annual cell size patterns to seasonal climatic conditions. Results indicated site-specific anatomical adjustment such as smaller and thicker tracheids at the dryer site but also showed a strong climatic imprint on the intra-annual pattern of tracheid size. Site differences in cell size reflected expected structural adjustments against cavitation failures. Differences between intra-annual patterns, however, indicated a response to seasonal changes in water availability whereby cells formed under drought conditions were smaller and thicker, and vice versa. This relationship was more manifest and stable at the dryer sit

Loss of BRCA1 or BRCA2 markedly increases the rate of base substitution mutagenesis and has distinct effects on genomic deletions

Loss-of-function mutations in the BRCA1 and BRCA2 genes increase the risk of cancer. Owing to their function in homologous recombination repair, much research has focused on the unstable genomic phenotype of BRCA1/2 mutant cells manifest mainly as large-scale rearrangements. We used whole-genome sequencing of multiple isogenic chicken DT40 cell clones to precisely determine the consequences of BRCA1/2 loss on all types of genomic mutagenesis. Spontaneous base substitution mutation rates increased sevenfold upon the disruption of either BRCA1 or BRCA2, and the arising mutation spectra showed strong and specific correlation with a mutation signature associated with BRCA1/2 mutant tumours. To model endogenous alkylating damage, we determined the mutation spectrum caused by methyl methanesulfonate (MMS), and showed that MMS also induces more base substitution mutations in BRCA1/2-deficient cells. Spontaneously arising and MMS-induced insertion/deletion mutations and large rearrangements were also more common in BRCA1/2 mutant cells compared with the wild-type control. A difference in the short deletion phenotypes of BRCA1 and BRCA2 suggested distinct roles for the two proteins in the processing of DNA lesions, as BRCA2 mutants contained more short deletions, with a wider size distribution, which frequently showed microhomology near the breakpoints resembling repair by non-homologous end joining. An increased and prolonged gamma-H2AX signal in MMS-treated BRCA1/2 cells suggested an aberrant processing of stalled replication forks as the cause of increased mutagenesis. The high rate of base substitution mutagenesis demonstrated by our experiments is likely to significantly contribute to the oncogenic effect of the inactivation of BRCA1 or BRCA2

The climate sensitivity of Norway spruce [Picea abies (L.) Karst.] in the southeastern European Alps

Tree ring chronologies were developed from trees growing at two sites in Slovenia which differed in their ecological and climatological characteristics. Ring width, maximum latewood density, annual height increment and latewood cellulose carbon isotope composition were developed at both sites and time-series verified against instrumental climate data over the period (AD 1960–AD 2002). Ring width sensitivity to summer temperature is site-dependent, with contrasting responses at alpine and lowland sites. Maximum density responds to September temperatures, suggesting lignification after cell division has ended for the season. Stable carbon isotopes have great potential, responding to summer temperature at oth alpine and lowland stands. Height increment appears relatively insensitive to climate, and is likely to be dominated by local stand dynamics

Comparison of the structure and flexural properties of Moso, Guadua and Tre Gai bamboo

Bamboo is an underutilized resource widely available in countries with rapidly developing economies. Structural bamboo products, analogous to wood products, allow flexibility in the shape and dimensions of bamboo structural members. Here, the ultrastructure, microstructure, cell wall properties and flexural properties of three species of bamboo (Moso, Guadua and Tre Gai) are compared. At a given density, the axial modulus of elasticity of Guadua is higher than that of Moso or Tre Gai, which are similar; ultrastructural results suggest that Guadua has a higher solid cell wall stiffness. At a given density, their moduli of rupture are similar.National Science Foundation (U.S.) (OISE-1258574