Gestión de servicios IT mediante códigos QR

Grado en Ingeniería Informátic

Manifestação patológica em sistemas geopoliméricos produzidos com metacaulim : avaliação da susceptibilidade no desenvolvimento de eflorescências

Os geopolímeros são uma nova classe de ligantes cimentícios, alternativa ao cimento Portland na construção civil. Estes novos ligantes são constituídos por uma reação química entre duas partes, um ativador alcalino e um aluminossilicato amorfo (precursor). Geopolímeros produzidos com metacaulim, tendem a desenvolver eflorescências, uma manifestação patológica que pode prejudicar a integridade estrutural do material. As eflorescências são formadas principalmente devido ao formato flocular do caulim, às impurezas presentes no precursor e ao excesso de sais presentes dos ativadores por meio da cristalização de sais. Esta manifestação patológica pode acontecer internamente e externamente, variando de acordo com condições do ambiente. O presente trabalho tem como objetivo avaliar como a cristalização dos sais se comporta com essas alterações na composição dos materiais a partir de diferentes dosagens de ativadores, adição de pigmentação a base de óxido de ferro e revestimento em resina acrílica em argamassas geopoliméricas. O trabalho utilizou de dois tipos diferentes de metacaulim, comercial e produzido em laboratório. Foi utilizado silicato de sódio e hidróxido de sódio como ativadores, sendo as relações da dosagem medidas em SiO2/NaOH,(Ms=1,0 e Ms=0,5). O programa experimental baseou-se nas técnicas de aceleração de eflorescência por meio da capilaridade ascendente da água, ensaio de resistência à compressão axial e ensaio de resistência à flexão. A partir da análise de resultados, foi possível concluir que as amostras com Ms=1,0 apresentaram melhor desempenho nos ensaios de resistência mecânica e no ensaio de aceleração na formação de eflorescência. Os geopolímeros produzidos com metacaulim produzido em laboratório também obtiveram melhores resultados nos três ensaios deste trabalho. A adição de pigmento baseado em óxido de ferro obteve maior resistência à compressão axial quando comparado aos resultados das misturas sem o pigmento. Por fim, concluiu-se que o revestimento dos corpos de prova em resina acrílica não reduziu a cristalização dos sais e a formação de eflorescências, não impedindo assim, a manifestação desta patologia

Interpreting the First CMS and ATLAS SUSY Results

The CMS and the ATLAS Collaborations have recently reported on the search for supersymmetry with 35 pb$^{-1}$ of data and have put independent limits on the parameter space of the supergravity unified model with universal boundary conditions at the GUT scale for soft breaking, i.e., the mSUGRA model. We extend this study by examining other regions of the mSUGRA parameter space in $A_0$ and $\tan\beta$. Further, we contrast the reach of CMS and ATLAS with 35 pb$^{-1}$ of data with the indirect constraints, i.e., the constraints from the Higgs boson mass limits, from flavor physics and from the dark matter limits from WMAP. Specifically it is found that a significant part of the parameter space excluded by CMS and ATLAS is essentially already excluded by the indirect constraints and the fertile region of parameter space has yet to be explored. We also emphasize that gluino masses as low as 400 GeV but for squark masses much larger than the gluino mass remain unconstrained and further that much of the hyperbolic branch of radiative electroweak symmetry breaking, with low values of the Higgs mixing parameter $\mu$, is essentially untouched by the recent LHC analysis.Comment: 3 figure panels, 10 plot

Land Use Change Affects Soil Organic Carbon: An Indicator of Soil Health

Soil organic carbon (SOC) is a major indicator of soil health. Globally, soil contains approximately 2344 Gt of organic carbon (OC), which is the largest terrestrial pool of OC. Through plant growth, soil health is connected with the health of humans, animals, and ecosystems. Provides ecosystem services which include climate regulation, water supplies and regulation, nutrient cycling, erosion protection and enhancement of biodiversity. Global increase in land use change from natural vegetation to agricultural land has been documented as a result of intensification of agricultural practices in response to an increasing human population. Consequently, these changes have resulted in depletion of SOC stock, thereby negatively affecting agricultural productivity and provision of ecosystem services. This necessitates the need to consider technological options that promote retention of SOC stocks. Options to enhance SOC include; no-tillage/conservation agriculture, irrigation, increasing below-ground inputs, organic amendments, and integrated, and diverse cropping/farming systems. In addition, land use conversion from cropland to its natural vegetation improves soil C stocks, highlighting the importance of increasing agricultural production per unit land instead of expanding agricultural land to natural areas

Nitric oxide orchestrates metabolic rewiring in M1 macrophages by targeting aconitase 2 and pyruvate dehydrogenase.

Profound metabolic changes are characteristic of macrophages during classical activation and have been implicated in this phenotype. Here we demonstrate that nitric oxide (NO) produced by murine macrophages is responsible for TCA cycle alterations and citrate accumulation associated with polarization. 13C tracing and mitochondrial respiration experiments map NO-mediated suppression of metabolism to mitochondrial aconitase (ACO2). Moreover, we find that inflammatory macrophages reroute pyruvate away from pyruvate dehydrogenase (PDH) in an NO-dependent and hypoxia-inducible factor 1α (Hif1α)-independent manner, thereby promoting glutamine-based anaplerosis. Ultimately, NO accumulation leads to suppression and loss of mitochondrial electron transport chain (ETC) complexes. Our data reveal that macrophages metabolic rewiring, in vitro and in vivo, is dependent on NO targeting specific pathways, resulting in reduced production of inflammatory mediators. Our findings require modification to current models of macrophage biology and demonstrate that reprogramming of metabolism should be considered a result rather than a mediator of inflammatory polarization

Dark sectors 2016 Workshop: community report

This report, based on the Dark Sectors workshop at SLAC in April 2016, summarizes the scientific importance of searches for dark sector dark matter and forces at masses beneath the weak-scale, the status of this broad international field, the important milestones motivating future exploration, and promising experimental opportunities to reach these milestones over the next 5-10 years

An African-Specific Variant of TP53 Reveals PADI4 as a Regulator of p53-Mediated Tumor Suppression

TP53 is the most frequently mutated gene in cancer, yet key target genes for p53-mediated tumor suppression remain unidentified. Here, we characterize a rare, African-specific germline variant of TP53 in the DNA-binding domain Tyr107His (Y107H). Nuclear magnetic resonance and crystal structures reveal that Y107H is structurally similar to wild-type p53. Consistent with this, we find that Y107H can suppress tumor colony formation and is impaired for the transactivation of only a small subset of p53 target genes; this includes the epigenetic modifier PADI4, which deiminates arginine to the nonnatural amino acid citrulline. Surprisingly, we show that Y107H mice develop spontaneous cancers and metastases and that Y107H shows impaired tumor suppression in two other models. We show that PADI4 is itself tumor suppressive and that it requires an intact immune system for tumor suppression. We identify a p53–PADI4 gene signature that is predictive of survival and the efficacy of immune-checkpoint inhibitors. Significance: We analyze the African-centric Y107H hypomorphic variant and show that it confers increased cancer risk; we use Y107H in order to identify PADI4 as a key tumor-suppressive p53 target gene that contributes to an immune modulation signature and that is predictive of cancer survival and the success of immunotherapy