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In rural settings, the presence of water supply infrastructure does not guarantee that people will have access to dependable and high-quality drinking water. To evaluate deficiencies, an assessment of quality of service of rural drinking water supply systems (RDWSS) should be examined from a multi-criteria perspective, one that integrates economic, technical, administrative, and operational components of supplying water, which includes a variety of stakeholders to integrate their preferences in the development of a synthetic index. In this study, we followed a pioneering approach to evaluate the quality of service for RDWSS based on analytic hierarchy process (AHP) and Monte Carlo simulations. We empirically applied the approach to 40 RDWSS in Chile. The weights of a set of 14 performance indicators were allocated by representatives of the communities that manage the RDWSS and experts on technical and administrative issues revelling the different preferences of decision-makers. We found that there are significant differences in the quality of service provided by the RDWSS evaluated. The information provided by the synthetic indicator would be very helpful in supporting decision makers needing to prioritize investments among drinking water supplies in rural settings. • The quality of service of rural drinking water supply systems was evaluated. • Uncertainty was considered in weights allocated to several criteria. • Preferences of different decision-makers are significantly divergent. • The age and size of the water system affects its quality of service. [ABSTRACT FROM AUTHOR]

The Smooth Hammerhead Shark Sphyrna zygaena is a species with anti-tropical distribution in the eastern Pacific from California USA, to southern Chile with a remarkably gap in abundance in equatorial areas between southern Mexico and Central America. For temperate species, warm waters can represent oceanographic barriers limiting the gene flow between adjacent populations. The mtDNA control region was used to infer the phylogeography and historical demography of the Smooth Hammerhead in the eastern Pacific. An AMOVA comparing locations grouped into northern and southern eastern Pacific equatorial areas indicated significant genetic differentiation. Each population had a common haplotype separated by two mutational differences suggesting that divergence occurred very recently. The pattern of genetic differences matches with the anti-tropical distribution of S. zygaena in the eastern Pacific. Gene diversity was lower in the northern population when compared to the southern area, a pattern indicative of a recent founder event. Broadly, this pattern suggests a recent population expansion occurring 25,000–10,000 years. bp, during the last glacial cycle, when the drop of surface sea temperatures created favorable conditions at equatorial latitudes to cross the thermal barrier imposed by warm waters at equatorial latitudes. These genetically distinct population groups might lead to delineate a management plan that considers two separated stocks in the eastern Pacific. [ABSTRACT FROM AUTHOR]

Four lice species (Phthiraptera: Philopteridae, Menoponidae) were collected from three woodpecker species (Aves: Picidae) in central and southern Chile. We collected Penenirmus campephili Eichler and Menacanthus campephili Price & Emerson from Magellanic woodpecker ( Campephilus magellanicus, King); Menacanthus pici (Denny) and Penenirmus auritus (Scopoli) from the Chilean flicker ( Colaptes pitius Molina) and M. pici as a parasite from a Striped woodpecker ( Veniliornis lignarius Molina). The species P. auritus and M. campephili are new lice records for Chile. The description of both P. auritus and M. pici parasitizing the Chilean flicker and Striped woodpecker respectively, are new host-parasite associations. [ABSTRACT FROM AUTHOR]

Deserts are ideal geological scenarios to understand the climatic influence in the sedimentary processes. Arid environments are extremely sensitive to climate changes, which can be preserved through the geological record. The Atacama Desert in northern Chile, has erosion and rainfall rates extremely lows, allowing the preservation of surfaces and sedimentary deposits that records the onset of the hyper-arid conditions towards the upper-Miocene. The sedimentation from the Miocene to recent times in the Atacama Desert had been controlled by episodes of torrential and ephemeral rains, whose frequency decrease when aridity intensifies. Prolonged periods of hyper-aridity favor the development of stable surfaces that remain fossilized as stratigraphic hiatuses. These hiatus could reflect relatively long periods of time. Stages of minor aridity are characterized by a major accumulation of discrete torrential deposits separated by unconformities which corresponds to relatively short periods of time. Thus, can changes in the sedimentation frequency of torrential deposits be evidenced throughout the sedimentary record? Is the onset of hyper-arid conditions reflected in a decrease in the frequency of these deposits? To tackle these questions, we consider the Atacama Gravels deposits localized in the Rio Salado canyon, at the El Salvador region, as the study area. There, the gravel deposits fill a paleo-valley which is subsequently incised exposing the whole stratigraphy. At the top of these deposits, different pediments surfaces are developed. The gravel deposits comprise three sequences limited by stratigraphic discontinuity which likely represents hiatuses. The clasts count and the analysis of the fine-sediments in the matrix allows to reconstruct the provenance of the sediments, revealing that each sequence is dominated by different source areas. At the base of the younger sequence, an ash level of ca. 15 Ma is interbedded, whereas another of ca. 10 Ma is present towards the upper part of the same sequence. The sequences are slightly thinning and finning-upwards, and they are in onlap relation with each other, revealing a back-stepping of the system. The sedimentary facies through the entire deposits vary from fluvial channelized with phreatic calcretes at the base, to alluvial facies with sheet-flows/debris-flows deposits and a gypsisol level at the top, which reveals an aridification in the environment. Through the use of exposure ages in pediment surfaces using 21Ne and 10 Be, and by 21Ne in depth-profiles in the boundaries of the sequences, we propose to obtain the time-gap present in these discontinuities. Considering the available data-age in the basin, we expected to obtain ages in the pediment surfaces around 9 Ma, and time-gap of the hiatuses in the order of ma. We hope to determine the filling times of the basin, which is an example of an Andean forearc Cenozoic basin in an arid climate, and the paleoclimatic and environmental importance in terms of its geomorphological evolution. [ABSTRACT FROM AUTHOR]

The diagnosis and treatment of sore throat in pediatric patients attending one of two facilities at a university hospital: pediatric ambulatory facility (PAF) and emergency unit (EU) in a period of 14 months are described. There were 421 patients at the PAF and 289 at the EU, of whom 65% and 76% were studied for Streptococcus pyogenes respectively. Streptococcus were detected in both centers in 37% of cases, with a peak detection of 50% at ages 6 to 10 years. There were 217 patients without any bacteriological study, of whom 162 (75%) received antibiotics. The importance of bacteriological confirmation prior to antibiotic prescription in this disease is emphasized.