Archaeometallurgy in the Paraná Delta (Argentina): Composition, manufacture, and indigenous routes

The results of macroscopic, microscopic, and metallographic studies of archaeological metal objects from the Delta of the Paraná River (Argentina, South America) are presented. The aim of these studies was to determine the chemical composition and the manufacturing techniques of these allochthonous objects frequently placed in human burials. The results were discussed taking into account archaeological and ethnohistorical information in order to understand the significance of metals and the indigenous routes to the Paraná River. We concluded that the metal pendants and beads recovered in the Paraná Delta were manufactured from copper by casting in open moulds and hammering. Finished metal objects reached the Paraná River as a result of exchange circuits involving transport across pre-Hispanic routes from the production centres in the Andes. Metal objects from distant geographical areas were used to mark social ranks within the groups and were symbols of prestige displayed by local leaders.Facultad de Ciencias Naturales y MuseoConsejo Nacional de Investigaciones Científicas y Técnica

Priority-Based Human Resource Allocation in Business Processes

In Business Process Management Systems, human resource management typically covers two steps: resource assignment at design time and resource allocation at run time. Although concepts like rolebased assignment often yield several potential performers for an activity, there is a lack of mechanisms for prioritizing them, e.g., according to their skills or current workload. in this paper, we address this research gap. More specifically, we introduce an approach to define resource preferences grounded on a validated, generic user preference model initially developed for semantic web services. Furthermore, we show an implementation of the approach demonstrating its feasibility. Keywords: preference modeling, preference resolution, priority-based allocation, priority ranking, RAL, resource allocation, SOUP

Semiconducting Monolayer Materials as a Tunable Platform for Excitonic Solar Cells

The recent advent of two-dimensional monolayer materials with tunable optoelectronic properties and high carrier mobility offers renewed opportunities for efficient, ultra-thin excitonic solar cells alternative to those based on conjugated polymer and small molecule donors. Using first-principles density functional theory and many-body calculations, we demonstrate that monolayers of hexagonal BN and graphene (CBN) combined with commonly used acceptors such as PCBM fullerene or semiconducting carbon nanotubes can provide excitonic solar cells with tunable absorber gap, donor-acceptor interface band alignment, and power conversion efficiency, as well as novel device architectures. For the case of CBN-PCBM devices, we predict the limit of power conversion efficiencies to be in the 10 - 20% range depending on the CBN monolayer structure. Our results demonstrate the possibility of using monolayer materials in tunable, efficient, polymer-free thin-film solar cells in which unexplored exciton and carrier transport regimes are at play.Comment: 7 pages, 5 figure

Inflammatory cytokines and biofilm production sustain Staphylococcus aureus outgrowth and persistence: A pivotal interplay in the pathogenesis of Atopic Dermatitis

Individuals with Atopic dermatitis (AD) are highly susceptible to Staphylococcus aureus colonization. However, the mechanisms driving this process as well as the impact of S. aureus in AD pathogenesis are still incompletely understood. In this study, we analysed the role of biofilm in sustaining S. aureus chronic persistence and its impact on AD severity. Further we explored whether key inflammatory cytokines overexpressed in AD might provide a selective advantage to S. aureus. Results show that the strength of biofilm production by S. aureus correlated with the severity of the skin lesion, being significantly higher (P < 0.01) in patients with a more severe form of the disease as compared to those individuals with mild AD. Additionally, interleukin (IL)-β and interferon γ (IFN-γ), but not interleukin (IL)-6, induced a concentration-dependent increase of S. aureus growth. This effect was not observed with coagulase-negative staphylococci isolated from the skin of AD patients. These findings indicate that inflammatory cytokines such as IL1-β and IFN-γ, can selectively promote S. aureus outgrowth, thus subverting the composition of the healthy skin microbiome. Moreover, biofilm production by S. aureus plays a relevant role in further supporting chronic colonization and disease severity, while providing an increased tolerance to antimicrobials

Arabidopsis S2Lb links AtCOMPASS-like and SDG2 activity in H3K4me3 independently from histone H2B monoubiquitination.

The functional determinants of H3K4me3, their potential dependency on histone H2B monoubiquitination, and their contribution to defining transcriptional regimes are poorly defined in plant systems. Unlike in Saccharomyces cerevisiae, where a single SET1 protein catalyzes H3K4me3 as part of COMPlex of proteins ASsociated with Set1 (COMPASS), in Arabidopsis thaliana, this activity involves multiple histone methyltransferases. Among these, the plant-specific SET DOMAIN GROUP 2 (SDG2) has a prominent role. We report that SDG2 co-regulates hundreds of genes with SWD2-like b (S2Lb), a plant ortholog of the Swd2 axillary subunit of yeast COMPASS. We show that S2Lb co-purifies with the AtCOMPASS core subunit WDR5, and both S2Lb and SDG2 directly influence H3K4me3 enrichment over highly transcribed genes. S2Lb knockout triggers pleiotropic developmental phenotypes at the vegetative and reproductive stages, including reduced fertility and seed dormancy. However, s2lb seedlings display little transcriptomic defects as compared to the large repertoire of genes targeted by S2Lb, SDG2, or H3K4me3, suggesting that H3K4me3 enrichment is important for optimal gene induction during cellular transitions rather than for determining on/off transcriptional status. Moreover, unlike in budding yeast, most of the S2Lb and H3K4me3 genomic distribution does not rely on a trans-histone crosstalk with histone H2B monoubiquitination. Collectively, this study unveils that the evolutionarily conserved COMPASS-like complex has been co-opted by the plant-specific SDG2 histone methyltransferase and mediates H3K4me3 deposition through an H2B monoubiquitination-independent pathway in Arabidopsis

Estudio comparativo de la movilidad cervical, cinestesia cervical y la movilidad oculomotora entre sujetos con dolor cervical crónico y sujetos asintomáticos.

Introducción: El dolor cervical es un síntoma que afecta a un alto porcentaje de la población adulta, se estima que entre el 30 y el 50 % lo sufren al menos un día al año. Muchos de los sujetos con dolor cervical tienen restringida la movilidad cervical, pero también presentan otros signos como disminución de la capacidad sensoriomotora o alteraciones oculomotoras. Los estudios que comparan aspectos de movilidad cervical, capacidad sensoriomotora y movilidad ocular entre sujetos asintomáticos y sujetos con dolor cervical son escasos. Objetivo: Comparar la movilidad, la cinestesia y el dolor entre sujetos con dolor cervical crónico y sujetos asintomáticos. Material y método: Es un estudio transversal, observacional y comparativo. Se registraron distintas variables: intensidad del dolor, índice de discapacidad cervical, rango de movimiento cervical, rango de movimiento cervical superior, cinestesia cervical y la movilidad ocular. Resultados: Cincuenta y ocho adultos participaron en el estudio (21 hombres (36,2 %) y 37 mujeres, la edad media fue de 41,98 ± 12,48), 29 sujetos por grupo. El grupo con dolor cervical crónico mostró restricción en el rango de movimiento hacia la extensión, la rotación derecha y la rotación izquierda y en el test de flexión rotación hacia la derecha. En el test de seguimiento ocular lento (0,044) el grupo de dolor cervical crónico presentaba mayor dificultad que el grupo asintomático. Conclusión: Este estudio sugiere que el dolor cervical crónico afecta a la movilidad de la columna cervical, la cinestesia cervical y el control oculomotor comparado con sujetos asintomáticos