First record of the invasive bee Anthidium manicatum (Hymenoptera: Megachilidae) in Chile

The Palearctic wool carder bee Anthidium manicatum (Linnaeus) is recorded for the first time in Chile based on eight specimens collected on Lavandula sp. (Lamiaceae) in San Bernardo, Metropolitan Region.  This new record expands the invasive range of this species in South America, confirming previous predictions based on an ecological niche model

Oi merger with Portugal Telecom: a strategic partnership

A Work Project, presented as part of the requirements for the Award of a Masters Degree in Finance from the NOVA – School of Business and EconomicsThis work seeks to explain and quantify the synergies resultant from the merger between Portugal Telecom and Oi. The main question we analyze throughout our analysis was whether the merger could bring some advantages that wouldn’t be achieved through the previous industrial alliance and to whom would the merger be more beneficial. Our conclusion was that since it will be impossible to replicate the Meo brand, the synergies should resume to faster cost cutting gains and interest payment savings through a capital increase which will be used to repay debt, besides enjoying a larger scale, accounting for minimal synergies

Entre Baumgarten y Aristóteles. Una reunión celebrativa

Entre Baumgarten y Aristóteles. Una reunión celebrativ

B-spline sectional model for general 3D effects in reinforced concrete elements

In this paper, an efficient sectional model for the nonlinear analysis of reinforced concrete elements sensible to 3D stress-components effects is presented. The classic plane-sections kinematic hypothesis is enhanced with a warping-distortion displacement field, which enables the model to reproduce the interaction between normal and tangential forces. The complementary field is obtained explicitly considering the inter-fiber equilibrium. This is solved using b-splines interpolation on the cross-section domain. The proposed method significantly reduces the number of unknowns compared with a finite element solution. The model is able to reproduce the interaction of longitudinal and transverse reinforcement with the concrete matrix. The validation shows that the presented model reproduces accurately complex failure modes as pure shear and coupling between bending and torsion. Further, as the transverse reinforcement is considered explicitly, confinement can be simulated in an objective manner. The presented model is an efficient tool for nonlinear analysis of reinforced concrete sections under general loading.Peer ReviewedPostprint (author's final draft

A new concrete plastic-damage model with an evolutive dilatancy parameter

Typical plastic-damage models for concrete use a constant dilatancy parameter. On problems sensitive to confinement and shear softening, this parameter needs ad hoc calibration to fit experimental observations. This makes the model not objective for general applications. To overcome this issue, in this paper, a constitutive plastic-damage model with evolutive dilatancy is proposed for concrete. The evolution of dilatancy is made dependent on the plastic-damage and stress states. The proposed evolution law is validated by comparison of numerical simulations with available experimental results. The validation includes: concrete specimens under uniaxial compression measuring the free expansion, passively confined concrete specimens with different confining materials, and reinforced concrete panels under in-plane shear. It is concluded that the model accurately reproduces concrete lateral expansion through different nonlinear states. Proper modeling of concrete nonlinear expansion proves essential for capturing the response in a number of situations: softening under high shear stresses, confinement, and ductility assessment.Peer ReviewedPostprint (author's final draft

39. Modulation of Histone Dosage and Chromatin Dynamics Regulates AAV Transduction

Recombinant adeno-associated vectors (AAVs) have gained momentum due to their combined characteristics of safety and efficiency. Nonetheless, the identity of the host functions intercepting the AAV transduction pathway still needs to be thoroughly understood.To address this issue on a genome-wide scale, we previously performed an unbiased RNAi high throughput screening (HTS; 18,120 human target genes) and identified 710 negative and 414 positive regulators of AAV efficiency. Based on the results obtained and with the purpose to identify factors involved in single-stranded (ss) AAV genome processing, we compared, again in an HTS format, siRNAs affecting ssAAV, but dispensable for scAAV transduction. One of the genes identified was ERI-1. While the effects of this protein were negligible on scAAV transduction, its knock down or overexpression lead to a 5 fold decrease or 2-7 fold increase of ssAAV efficiency, respectively.ERI-1 is a 3'-exoribonuclease known to degrade endogenous miRNAs and histone mRNAs. Indeed, we observed that AAV transduction negatively correlated with histone mRNA levels. Chromatin immunoprecipitation (ChIP) studies aimed at assessing the extent of chromatinization of the AAV genome revealed that the overexpression of ERI-1 determined an over 10-fold, selective reduction on ssAAV genome association with H3 and H4, while changes were negligible for scAAV DNA and for control cellular genes. Consistent with chromatin exerting a repressive role on ssAAV transduction, we also noticed that the downregulation of the main replication-dependent histone chaperone CAF-1 induced an over 20-fold increase in transduction. Increase of ssAAV2 transduction by ERI-1 also decreased the association, with the viral DNA, of proteins of the cellular DNA damage response (DDR; e.g. Nbs1 and Mre11), which our previous work had indicated as inhibitory of AAV transduction.Interestingly, DNA damage per se induced downregulation of histone gene expression. In particular, hydroxyurea, a drug markedly increasing AAV transduction, also determined histone mRNA degradation, an effect that required integrity of ERI-1.These results underline the importance of chromatin and its dynamic regulation in determining the fate of productive AAV transduction. These findings can be exploited for the development of more effective AAV-mediated gene delivery strategies

Active accessibility: A review of operational measures of walking and cycling accessibility

Active travel is enthusiastically promoted in the Westernworld due to its clear and demonstrated individual and collective benefits. While active travel has been shown to be associated with featuresof the built environment such as density and land-use mix, it is alsoassociated with walking and cycling accessibility-which we designateas active accessibility. However, the measurement of active accessibility is not straightforward and it can represent significantly differentfeatures of the built environment. This paper presents an extensivereview of published research that measures active accessibility. Weclassified the literature into four categories based on the methodologyused: distance-based, gravity-based or potential, topological or infrastructure-based, and walkability and walk score-type measures. A fifthcategory was created to classify outliers consisting of distinct methodological approaches or hybrids of the four main categories. We arguethat almost all of these methods have conceptual and computationallimitations, and that there are inconsistencies in the use of conceptsand terms. Furthermore, no sensitivity analysis was carried out on theselected parameters. We conclude by presenting some guidelines thatmight improve the value and clarity of active accessibility research,theory, and practice