RV POSEIDON Fahrtbericht / Cruise Report POS 453 & 458 “COMM3D” : Crustal Structure and Ocean Mixing observed with 3D Seismic Measurements, 20.05. – 12.06.2013 (POS453) Galway, Ireland – Vigo, Portugal ; 24.09. – 17.10.2013 (POS458) Vigo, Portugal – Vigo, Portugal

Cruise P453 & P458 with R/V POSEIDON aim to conduct 3D wide-angle ocean bottom recording (OBR) data during the acquisition of 3D multichannel seismic (MCS) reflection data (D. Sawyer, Rice University & T.J. Reston, Birmingham) and to analyze and interpret a highresolution densely sampled 2D OBR wide-angle profile. The primary goal of the wide-angle data will be to provide an accurate and detailed 3D P-wave velocity model for the 3D reflection data. Particularly the densely sampled 2D profile will help to determine the degree of thinning within the crust and the degree of serpentinisation of the uppermost mantle. The collection of 3D MCS data gives the unique opportunity to obtain densely sampled water column reflection data and to analyze spatial and temporal (4D) variations of the internal wave field which will yield new understanding and insights into water mass mixing processes offshore west Iberia. Contemporaneously hydrographic data will be collected to calibrate and analyze the oceanic thermohaline structures originating from the interaction between Atlantic waters and the Mediterranean Sea Outflow

Update on the approach to smoking in patients with respiratory diseases.

Smoking is the leading cause of respiratory disease (RD). The harmful effects of smoking on the respiratory system begin in utero and influence immune responses throughout childhood and adult life. In comparison with ?healthy? smokers, smokers with RD have peculiarities that can impede smoking cessation, such as a higher level of nicotine dependence; nicotine withdrawal; higher levels of exhaled carbon monoxide; low motivation and low self-efficacy; greater concern about weight gain; and a high prevalence of anxiety and depression. In addition, they require more intensive, prolonged treatment. It is always necessary to educate such individuals about the fact that quitting smoking is the only measure that will reduce the progression of RD and improve their quality of life, regardless of the duration and severity of the disease. Physicians should always offer smoking cessation treatment. Outpatient or inpatient smoking cessation treatment should be multidisciplinary, based on behavioral interventions and pharmacotherapy. It will thus be more effective and cost-effective, doubling the chances of success

Respuesta de la estructura fitoplanctónica a las perturbaciones antrópicas de un lago templado

The Rapel reservoir (34º S; 71ºW) was impounded in 1968 and the phytoplankton community shows the effects of eutrophication processes and later contamination due to the affluence of agrochemicals and copper mining clear water tailings. Phytoplankton diverse associations distribution along the reservoir is homogenous because of the system’s hydrodynamic characteristics with retention times between 12days and three months at the different areas of the reservoir and daily winds that maintain a turbulent mix of the water column. Micro algae associate in three groups that correspond to periods of different chemical water quality and the associations here described show that taxa such as Microcystis aeruginosa, Oscillatoria sp., and Aulacoseira granulata although tolerant to eutrophy are rapidly affected by copper. The response to the increase of the copper concentration correspons with a decrease in species richness and with a higher abundance of Dictyiosphaerium pulchellum, Coelastrum microporum and Pediastrum simplex as copper tolerant speciesEl Embalse Rapel (34º S; 71ºW) fue generado en 1968, y la comunidad fitoplanctónica señala los efectos de procesos de eutroficación y posterior contaminación por la recepción de agroquímicos y aguas claras de relave de minería del cobre. La distribución de las diversas asociaciones fitoplanctónicas es homogénea a lo largo del embalse debido a las características hidrodinámicas del sistema con tiempos de retención entre 12 días y tres meses en las áreas diferentes del embalse y vientos diarios que mantienen una mezcla turbulenta de la columna de agua. Las microalgas se asocian en tres grupos correspondientes a los períodos de diferente calidad química del agua y las asociaciones aquí descritas señalan que taxa como Microcystis aeruginosa, Oscillatoria sp. y Aulacoseira granulata aunque tolerantes a eutrofía son rapidamente afectadas por cobre. La respuesta al aumento de la concentración de cobre señala una disminución en riqueza de especies y un incremento de Dictyiosphaerium pulchellum, Coelastrum microporum y Pediastrum simplex tolerantes al metal

Toxicity of a soluble peptide from Microcystis sp. to zooplankton and fish

SUMMARY. A soluble cell fraction lethal to Daphnia magna was isolated by the disruption of net phytoplankton from eutrophic Aculeo Lake. The phytoplankton of this lake is dominated by Microcystis sp. The soluble fraction was also lethal to common native zooplankton, including the rotifers Keratella sp., Trichocerca similis, the copepod Boeckella sp., and the cladoceran Chydorus sphaericus. In addition, a partially purified soluble component of the lethal fraction caused the death of the fish Gambusia affinis. The specific toxicity of the soluble fraction from phytoptankton varied four‐ to six‐fold seasonally with peaks during periods of warm temperature. Our results suggest that releases of a toxic peptide from Microcystis sp. may be the cause of massive fish kills at the study site, Aculeo Lake. Copyright © 1990, Wiley Blackwell. All rights reserve

Embryological development of the high-altitude killifish Orestias ascotanensis Parenti 1984 (Teleostei: Cyprinodontidae)

Orestias ascotanensis Parenti is a critically-endangered fish species endemic to the Ascotán salt pan springs. Given the importance of reproduction and early development in effective conservation of fish populations, this study describes the embryonic development of O. ascotanensis under laboratory conditions. Between 2014 and 2015, 50 individuals were captured and maintained under controlled conditions, including temperature, photoperiod and feeding regimen, to induce spawning for artificial fertilization. Females were subjected to hormone therapy with Ovaprim®. Water temperature was maintained at 20 °C (± 1 °C), conductivity at 2800–3600 μS·cm−1 and photoperiod at 16:8 (light hours: dark hours). Males showed changes in color and courtship behavior, and females developed a slightly bulging belly. Eggs were 1.55–2.5 mm in diameter, with abundant yolk and dozens of adhesion filaments. Embryonic development lasted 14–18 days; it was divided into five periods, which can be sub-divided into 21 stages, from fertilization to hatching. O. ascotanensis showed indications of partial spawning species, including oocytes at different stages of development, relatively large eggs as compared to adult fish length and low batch spawning. Characteristics such as partial spawning, highly-pigmented eggs and larvae and advanced larval development at hatching could be adaptations to the extreme conditions of the salt pan springs, including high levels of ultraviolet radiation and salinity as well as significant daily temperature changes

Genetic structure in remnant populations of an endangered cyprinodontid fish, Orestias ascotanensis, endemic to the Ascotán salt pan of the Altiplano

The impact of recent habitat fragmentation on population genetic diversity and structure has often been studied, mainly related to anthropogenic causes; however its long-term effect has been much less evaluated. In this study we analyzed the genetic variability of Orestias ascotanensis, a fish endemic to the Ascotán salt pan of Chile. This species, which formed a single and large population during the last wet period that ended 10,000 years ago, is currently represented by small populations inhabiting freshwater springs on the eastern border of the salt pan. Therefore, this species represents a unique model to evaluate the consequences of a drastic habitat fragmentation process that initiated thousands of years ago. Analysis of the control region of the mitochondrial DNA revealed high genetic diversity (haplotipic diversity ranged between 0. 78 and 0. 94) and marked differences among populations (ΦST = 0. 46). Estimated effective population sizes greatly surpassed the real sizes, part

Temporal and spatial distribution of rotifera in a Chilean reservoir: A possible effect of impoundment hydrodynamics

Rotifers were sampled at monthly intervals for a year at four monitoring stations in Rapel Reservoir (a hydroelectric impoundment) in Central Chile (34°02′S; 71°35′W). Fifteen species were identified, but only Keratella cochlearis was consistently found at each station, it usually was the most abundant (> 50% of total rotifers). Marked differences were found among sites; stations I and 2, those nearest to the dam, showed greatest rotifer densities in spring and autumn. Station 4, that nearest to the inflowing rivers, had its highest rotifer abundance in summer. Station 8 had the highest mean density but the least marked seasonal changes in rotifer numbers. The impoundment water dynamics and the relative locations within the lake (distance from the dam or from the rivers) are suggested as determinants for different rotifer assemblages and, probably, for most other planktonic organisms. © 1984 Dr W. Junk Publishers

Effect of zinc and benzalkonium chloride on Nitrosomonas communis and potential nitrification in soil

A bacterial contact assay is described which uses a chemoautotrophic microorganism, Nitrosomonas communis (strain Nm2) to evaluate the biological effect of contaminated soils. The effects of two toxicants on the ammonium oxidation activity of the autochthonous microbial population in the soil are compared with inhibition of the same biological response in the new monospecies bioassay. Experiments were performed using soil samples dosed with organic and inorganic contaminants (benzalkonium chloride and zinc) to demonstrate the mode of operation and the sensitivity of the bioassay. The EC50 values of zinc and benzalkonium chloride were calculated to be 171 and 221 mg kg-1 soil, respectively. The toxic response provided by the bioassay can thus predict the effect of soil pollutants on the autochthonous nitrifying bacteria. © 2001 John Wiley & Sons, Inc

Competitive interaction between introduced rainbow trout and native silverside in a Chilean stream

The field experiment presented here elucidates the competitive effect of exotic trout on Chilean silverside. This is the first local experimental work that demonstrates the negative effect of trout on native fish from Chile. Interspecific competition between the Chilean Silverside Basilichthys australis and the rainbow trout Oncorhynchus mykiss was evaluated by an experimental design that used enclosures in a stream of central Chile. Nine enclosures were equally assigned to three treatments, low density, with two silversides; interspecific treatment, with two silversides and four trout; and high density treatment, with six silversides. The results indicate that silversides were weaker competitors, negatively affected by the presence of trout; they showed significant weight loss and reduction in stomach content in the presence of trout. © Springer Science + Business Media B.V. 2009