Library of high and mid-resolution spectra in the CaII H & K, Hα, Hβ, NaI D_1, D_2, and HeI D3 line regions of F, G, K and M field stars

In this work we present spectroscopic observations centered in the spectral lines most widely used as optical indicators of chromospheric activity (Hα, Hβ, CaII H & K, and HeI D_3) in a sample of F, G, K and M chromospherically inactive stars. The spectra have been obtained with the aim of providing a library of high and mid-resolution spectra to be used in the application of the spectral subtraction technique to obtain the active-chromosphere contribution to these lines in chromospherically active single and binary stars. This library can also be used for spectral classification purposes. A digital version with all the spectra is available via ftp and the World Wide Web (WWW) in both ASCII and FITS formats

Freshwater biodiversity and conservation in mediterranean climate streams of Chile.

In Chile, mediterranean climate conditions only occur in the Central Zone (ChMZ). Despite its small area, this mediterranean climate region (med-region) has been recognised as a hotspot for biodiversity. However, in contrast to the rivers of other med-regions, the rivers in the ChMZ have been studied infrequently, and knowledge of their freshwater biodiversity is scarce and fragmented. We gathered information on the freshwater biodiversity of ChMZ, and present a review of the current knowledge of the principal floral and faunal groups. Existing knowledge indicates that the ChMZ has high levels of endemism, with many primitive species being of Gondwanan origin. Although detailed information is available on most floral groups, most faunal groups remain poorly known. In addition, numerous rivers in the ChMZ remain completely unexplored. Taxonomic specialists are scarce, and the information available on freshwater biodiversity has resulted from studies with objectives that did not directly address biodiversity issues. Research funding in this med-region has a strong applied character and is not focused on the knowledge of natural systems and their biodiversity. Species conservation policies are urgently required in this highly diverse med-region, which is also the most severely impacted and most populated region of the country

Genetic and phenotypic diversity characterization of natural populations of the parasitoid Parvilucifera sinerae

Parasites exert important top-down control of their host populations. The host−parasite system formed by Alexandrium minutum (Dinophyceae) and Parvilucifera sinerae (Perkinsozoa) offers an opportunity to advance our knowledge of parasitism in planktonic communities. In this study, DNA extracted from 73 clonal strains of P. sinerae, from 10 different locations along the Atlantic and Mediterranean coasts, was used to genetically characterize this parasitoid at the species level. All strains showed identical sequences of the small and large subunits and internal transcribed spacer of the ribosomal RNA, as well as of the β-tubulin genes. However, the phenotypical characterization showed variability in terms of host invasion, zoospore success, maturation time, half-maximal infection, and infection rate. This characterization grouped the strains within 3 phenotypic types distinguished by virulence traits. A particular virulence pattern could not be ascribed to host-cell bloom appearance or to the location or year of parasite-strain isolation; rather, some parasitoid strains from the same bloom significantly differed in their virulence traits. Identical markers such as ITS and β-tubulin genes of P. sinerae strains from different geographic areas and from different years precludes their use in assessing intra-specific diversity and could indicate a recent dispersion of this species.Versión del editor2,393

Environmental Determinants of COVID 19 Transmission Across a Wide Climatic Gradient in Chile

Several studies have examined the transmission dynamics of the novel COVID-19 disease in different parts of the world. Some have reported relationships with various environmental variables, suggesting that spread of the disease is enhanced in colder and drier climates. However, evidence is still scarce and mostly limited to a few countries, particularly from Asia. We examined the potential role of multiple environmental variables in COVID-19 infection rate [measured as mean relative infection rate = (number of infected inhabitants per week / total population) × 100.000) from February 23 to August 16, 2020 across 360 cities of Chile. Chile has a large climatic gradient (≈ 40º of latitude, ≈ 4000 m of altitude and 5 climatic zones, from desert to tundra), but all cities share their social behaviour patterns and regulations. Our results indicated that COVID-19 transmission in Chile was mostly related to three main climatic factors (minimum temperature, atmospheric pressure and relative humidity). Transmission was greater in colder and drier cities and when atmospheric pressure was lower. The results of this study support some previous findings about the main climatic determinants of COVID-19 transmission, which may be useful for decision-making and management of the disease.Funding was provided by the Initiation Fondecyt project 11170390 to F.C.A. D.N. received a CONICYT-PFCHA/ Doctorado Nacional/2019-21191862 scholarship. A.C. received a scholarship of the National Secretariat of Science, Technology and Innovation (SENACYT, Panama) and by the National Research System of Panama (SNI; doctoral student category)

A uvbyβ survey of northern-hemisphere active binaries II: the m1 deficiency

New photometric observations, using the uvby and Hβ systems of 72 northern-hemisphere active binaries are discussed in order to explain the main characteristics of their spectral light intensity distribution. Values of the parameter δm1 range from 0.0 to 0.3 mag, which cannot be explained in terms of metal underabundance alone. The existence of some mechanism, responsible for such a colour-index anomaly, is thus suggested and is found to be in close relation with the involved degree of solar-type activity

Leptospirosis Prevalence in Patients with Initial Diagnosis of Dengue

Objective. To determine the prevalence of leptospirosis in patients from Veracruz with initial diagnosis of dengue and its association with risk factors. Materials and Methods. Transversal study in patients who sought medical attention under the suspicion of dengue. Backgrounds were researched and blood samples were drawn to determine dengue (NS1, RT-PCR) and leptospirosis (IFI). Simple frequencies, central tendency and dispersion measures, and prevalence and trust intervals at 95% (IC95%) were obtained. Prevalence reasons (RP) and IC95% were obtained and a multivariate logistic model was applied, using SPSS V15. Results. 171 patients were included, 56% women (32 ± 14 years) and 44% men (32 ± 17 years). 48% of the cases (IC95% 40.5–55.4) was positive to dengue, with a cut point of 1 : 80, seroprevalence for leptospirosis was of 6% (IC95% 2.7–10); 12% (IC95% 7–16.5) was positive to both pathologies and 34% was negative to both tests. Although the largest number of isolations corresponded to serotype 2, the four dengue virus serotypes were identified. In the bivariate analysis, overcrowding RP = 1.33, (IC = 0.46–3.5), bathing in rivers (RP = 1.31, IC = 0.13–7.4), and walking barefoot (RP = 1.39, IC = 0.58–3.3) were the variables associated with leptospirosis, although the relation was not statistically significant. Conclusions. Leptospirosis prevalence in subjects under suspicion of dengue fever is high, as well as the coincidence of both infections. The results show the coexistence of overlapped outbreaks of several diseases sharing the side of transmission. It is necessary the intentional search of other pathologies, such as influenza, rickettsiosis, and brucella, among others

Remoción de parásitos en aguas negras tratados en un sistema combinado de reactores anaeróbicos y lagunas de estabilización

El presente trabajo tiene como finalidad el estudio de la eficiencia de remoción de huevos de helmintos en un Sistema Combinado de Tratamiento (dos Reactores UASB y Lagunas de Estabilización) a escala piloto, ubicado en la Ciudad de Salta (Argentina). Se analizaron 19 muestras puntuales tomadas durante el periodo mayo-noviembre de 2002. En el Reactor 1 la remoción de los huevos de parásitos fue de 83% en invierno y del 92 % en verano. En el Reactor 2 las remociones fueron bajas probablemente porque no se formó un manto de lodos adecuado. Las remociones en las lagunas de estabilización fueron del 77 % y del 96 % en invierno y verano respectivamente. La remoción total del Sistema Combinado fue de 99,3 % en el periodo invernal y de 99,7 % en el periodo estival resultando ser una opción atractiva para el tratamiento de líquidos cloacales en regiones subtropicales.The objective this work was the study of the removal efficiency of helminthes eggs in a Combined System of Treatment made up by two reactors UASB and Lagoons of Stabilization on pilot scale. The system was located in the Sewage Treatment Plant in the city of Salta (Argentina). The analyses were carried out with 19 samples, during the period May-November of 2002. In the Reactor 1 parasites eggs removal was 83% during the winter and 92 % in the summer. In Reactor 2 removals were low, probably due to unsuitable sludge shape. The removals in stabilization ponds were of 77 % and 96 % in the respective periods. Total removal of helminthes eggs in the system was 99.3 % in the winter period and 99.7 % in the summer period turning out to be an attractive option for the treatment of sewage in subtropical regions.Asociación Argentina de Energías Renovables y Medio Ambiente (ASADES

Remoción de parásitos en aguas negras tratados en un sistema combinado de reactores anaeróbicos y lagunas de estabilización

El presente trabajo tiene como finalidad el estudio de la eficiencia de remoción de huevos de helmintos en un Sistema Combinado de Tratamiento (dos Reactores UASB y Lagunas de Estabilización) a escala piloto, ubicado en la Ciudad de Salta (Argentina). Se analizaron 19 muestras puntuales tomadas durante el periodo mayo-noviembre de 2002. En el Reactor 1 la remoción de los huevos de parásitos fue de 83% en invierno y del 92 % en verano. En el Reactor 2 las remociones fueron bajas probablemente porque no se formó un manto de lodos adecuado. Las remociones en las lagunas de estabilización fueron del 77 % y del 96 % en invierno y verano respectivamente. La remoción total del Sistema Combinado fue de 99,3 % en el periodo invernal y de 99,7 % en el periodo estival resultando ser una opción atractiva para el tratamiento de líquidos cloacales en regiones subtropicales.The objective this work was the study of the removal efficiency of helminthes eggs in a Combined System of Treatment made up by two reactors UASB and Lagoons of Stabilization on pilot scale. The system was located in the Sewage Treatment Plant in the city of Salta (Argentina). The analyses were carried out with 19 samples, during the period May-November of 2002. In the Reactor 1 parasites eggs removal was 83% during the winter and 92 % in the summer. In Reactor 2 removals were low, probably due to unsuitable sludge shape. The removals in stabilization ponds were of 77 % and 96 % in the respective periods. Total removal of helminthes eggs in the system was 99.3 % in the winter period and 99.7 % in the summer period turning out to be an attractive option for the treatment of sewage in subtropical regions.Asociación Argentina de Energías Renovables y Medio Ambiente (ASADES

Remoción de parásitos en aguas negras tratados en un sistema combinado de reactores anaeróbicos y lagunas de estabilización

El presente trabajo tiene como finalidad el estudio de la eficiencia de remoción de huevos de helmintos en un Sistema Combinado de Tratamiento (dos Reactores UASB y Lagunas de Estabilización) a escala piloto, ubicado en la Ciudad de Salta (Argentina). Se analizaron 19 muestras puntuales tomadas durante el periodo mayo-noviembre de 2002. En el Reactor 1 la remoción de los huevos de parásitos fue de 83% en invierno y del 92 % en verano. En el Reactor 2 las remociones fueron bajas probablemente porque no se formó un manto de lodos adecuado. Las remociones en las lagunas de estabilización fueron del 77 % y del 96 % en invierno y verano respectivamente. La remoción total del Sistema Combinado fue de 99,3 % en el periodo invernal y de 99,7 % en el periodo estival resultando ser una opción atractiva para el tratamiento de líquidos cloacales en regiones subtropicales.The objective this work was the study of the removal efficiency of helminthes eggs in a Combined System of Treatment made up by two reactors UASB and Lagoons of Stabilization on pilot scale. The system was located in the Sewage Treatment Plant in the city of Salta (Argentina). The analyses were carried out with 19 samples, during the period May-November of 2002. In the Reactor 1 parasites eggs removal was 83% during the winter and 92 % in the summer. In Reactor 2 removals were low, probably due to unsuitable sludge shape. The removals in stabilization ponds were of 77 % and 96 % in the respective periods. Total removal of helminthes eggs in the system was 99.3 % in the winter period and 99.7 % in the summer period turning out to be an attractive option for the treatment of sewage in subtropical regions.Asociación Argentina de Energías Renovables y Medio Ambiente (ASADES

Bloom dynamics of an exceptional red tide of the toxigenic dinoflagellate

The toxic dinoflagellate Alexandrium minutum generally proliferates in semi-enclosed sites such as estuaries, harbours and lagoons, where stratification, restricted circulation and accumulation of resting cysts set suitable conditions for its development. In the Galician Rías (NW Iberian Peninsula), its blooms follow also this pattern. They are recurrent in small, shallow estuarine bays inside the Rías, but rarely detected, and if so in minor amount, out of these areas. However, a massive proliferation of A. minutum from June to July 2018 in the Rías Baixas (Vigo and Pontevedra) changed this picture. The bloom initiated in semi-enclosed waters, as previously described for this species, but thereafter spread to the whole embayments where persisted more than one month. It generated a noticeable red tide with disperse patches that became heavily concentrated inside the port of Vigo. During that period shellfish harvesting closures and paralytic shellfish toxins in certain marine invertebrates and fish were reported for the first time in Spain. Meteorological conditions (higher than usual rains/runoff, sustained temperature increment and oscillating wind pattern promoting a series of upwelling-relaxation cycles) fostered optimal circumstances for the outbreak of A. minutum: strong vertical stratification and the alternation of retention and dispersion processes. Simulations from a particle tracking model portrayed the observed bloom development phases: onset, transport within the surface layer towards the interior parts of the Ría of Vigo, and dispersion all over the embayment. High concentrations of resting cysts were detected several months after the bloom, which may have favoured flourish of A. minutum in the following years, markedly in 2020