Penguin guano trace metals release to Antarctic waters: A kinetic modelling.

Penguin guano has been considered as a suitable bioindicator of the exposure to environmental contaminants in Antarctic environment. Although trace metal content values in penguin guano have been widely reported, the kinetics of their mobility in seawater have not been determined. In the present study, we have estimated the release rate of dissolved Cd, Co, Cu, Fe, Mn, Mo, Ni, Pb, V, and Zn from Gentoo (Pygoscelis papua) penguins guano to Antarctic seawater by 120 h laboratory and at external natural conditions of temperature and light experiments. A mathematical model using two metal pools guano (labile and equilibrium) and seawater compartments considering pseudo-first-order kinetics, is proposed in order to interpret and predict the release of trace metals. A good statistical agreement between experimental and modelled concentration values allows us obtention of kinetic parameters and partition coefficients (Kdi). These values allow to estimate releases into seawater from 5400 to 6.3 µg/day·penguin of Cu and V, respectively. More than 50 % of the initial content of all the studied elements are released during the first two hours, reaching 90 % release in the decreasing order of speed Ni â‰« Cu ≈ Mo > Mn > Co > Cd ≈ Pb; periods of up to one hour, Fe, V and Zn reach a maximum release and are then readsorbed. Equilibrium releases >90 % for Mo and Cd, and 55 % - 46 % for Co, Ni, Pb and Mn are obtained; Zn with 5.4 %, V with 1.7 % and Fe with 0.88 % show the lowest values. With an overwhelming growth of estimated population south of 60°S of 259.750 breeding pairs we estimate that the Gentoo penguin population is releasing annually in the Southern Ocean, 716 kg Cu, 188 kg Mn, 113 kg Fe, 102 kg Zn, 17.7 kg Mo, 12.0 kg Ni, 8.70 kg Cd, 4.59 kg Co, 6.27 kg Pb and 0.790 kg V of soluble metals.

Modelling the bioconcentration of Zn from commercial sunscreens in the marine bivalve Ruditapes philippinarum.

Sunscreens contain ZnO particles used as a UV filter cause adverse effects in the marine environment through the release of this metal into seawater and its bioaccumulation in organisms. A mathematical model using sunscreen colloidal residues, seawater and R. philippinarum clams as differentiated compartments, is proposed in order to interpret both the kinetic pattern and the bioaccumulation of Zn in clams. Two kinetic laboratory experiments were conducted, both with and without clams exposed to sunscreen concentrations from 0 to 200 mg L-1. Both the lowest value of uptake rate coefficient obtained when 5 mg L-1 of sunscreen is added (0.00688 L g-1 d-1) and the highest obtained at sunscreen addition of 100 mg L-1 (0.0670 L g-1 d-1), predict a lower bioavailability of Zn in a complex medium such as the seawater-sunscreen mixtures, in comparison to those studied in the literature. The efflux rate coefficient from clams to seawater increased from 0 to 0.162 d-1 with the sunscreen concentrations. The estimated value of the inlet rate coefficient at all studied concentrations indicates that there is a negligible colloidal Zn uptake rate by clams, probably due to the great stability of the organic colloidal residue. An equilibrium shift to higher values of Zn in water is predicted due to the bioconcentration of Zn in clams. The kinetic model proposed with no constant Zn (aq) concentrations may contribute to a more realistic prediction of the bioaccumulation of Zn from sunscreens in clams.

Spatial distribution and level of contamination of potentially toxic elements in sediments and soils of a biological reserve wetland, northern Amazon region of Ecuador.

This study quantifies the degree of pollution and assess the ecological risk of As, Ba, Cd, Co, Cr, Cu, Mo, Ni, Pb, V and Zn in sediments and soils of the Limoncocha Biological Reserve (Ecuador), identified as a Ramsar site with high ecological and socioeconomic value. The hydrologic system of the Reserve is mainly formed by two rivers that drain into the Limoncocha lagoon, which occupies only five percent of the protected area but support a high anthropic influence. Local statistical baseline of studied potentially toxic elements is established using cumulative frequency method, and Al is selected as reference element due to the good correlation with the studied elements. The grade of pollution and the potential ecological risk are evaluated applying three individual (Contamination Factor, Geo-accumulation Index and Enrichment Factor) and six integrated (Degree and modified degree of contamination, Pollution Load Index, Nemerow and modified Nemerow pollution indexes and potential ecological risk index) indices. Results analysis are based on the combined application of traditional statistics, multivariate data analysis and self organizing maps. Outcomes suggest to classify sediments and soils as "moderate contamination and enrichment" due mainly to the concentrations of Cu (66.4-110 mg/kg) and Cd (0.0262-0.808 mg/kg), derived from domestic wastewaters and agricultural activities, and in a lesser extent due to Mo (0.822-4.37 mg/kg), Ni (10.3-25.8 mg/kg), Co (7.27-24.8 mg/kg) and V (60.3-178 mg/kg), derived from oil field drilling activities. The distributions of As (0.328-8.83 mg/kg), Ba (143-1100 mg/kg), Pb (7.20-26.5 mg/kg), Zn (60.1-276 mg/kg) and Cr (10.1-48.6 mg/kg) are heterogeneous in the studied sampling sites. Sediments located next to the pier and at the central area of the Limoncocha lagoon, show moderate potential risk and according to sediment quality guidelines, the calculated mean Effect Range Median quotient (mERMq) classify the sites as medium-low priority risk level. A three-level classification of a mean quotient based on soil quality and soil potential uses is proposed. Soil sites with high anthropogenic activities show low to moderate potential ecological risk being classified as poor soil quality sites but with all potential soil uses allowed according to the legal limits for land uses in Ecuador.

Sunscreens as a New Source of Metals and Nutrients to Coastal Waters.

Studies detailing the environmental impact of sunscreen products on coastal ecosystems are considered a high priority. In the present study, we have determined the release rate of dissolved trace metals (Al, Cd, Cu, Co, Mn, Mo, Ni, Pb, and Ti) and inorganic nutrients (SiO2, P-PO43-, and N-NO3-) from a commercial sunscreen in seawater, and the role of UV radiation in the mobilization of these compounds. Our results indicate that release rates are higher under UV light conditions for all compounds and trace metals except Pb. We have developed a kinetic model to establish the release pattern and the contribution to marine coastal waters of dissolved trace metals and inorganic nutrients from sunscreen products. We conservatively estimate that sunscreen from bathers is responsible for an increase of dissolved metals and nutrients ranging from 7.54 × 10-4 % for Ni up to 19.8% for Ti. Our results demonstrate that sunscreen products are a significant source of metals and inorganic nutrients to coastal waters. The normally low environmental concentrations of some elements (e.g., P) and the toxicity of others (e.g., Pb) could be having a serious adverse effect on marine ecology in the Mediterranean Sea. This risk must not be ignored.

Volunteer Functions Inventory: A systematic review / El inventario de funciones del voluntariado: una revisión sistemática

The objective of this research study was to conduct a systematic review of the research on volunteers using Clary et al.’s VFI (1998). A total of 48 research studies including 67 independent samples met eligibility criteria. The total sample of the studies analyzed ranged from 20375 to 21988 participants, depending on the motivation analyzed. The results show that the Values factor obtained the highest mean score, both overall and in each type of volunteering, whereas the lowest scores were for the Career and Enhancement factors. Studies conducted with samples with a mean age under 40 years obtain higher scores on Career and Understanding scales when compared to studies in older samples. The group of studies with less than 50% women yield higher mean scores on the Social scale than studies with more than 50% women in the sample. All the scales show reliability coefficients between .78 and .84. Only eight of the articles provide data on the reliability of the scale with a mean value of .90. Of the 26 studies that performed factor analysis, 18 confirmed the original structure of six factors (AU)

Antecedentes: las motivaciones son variables clave para comprender el comportamiento de los voluntarios. El objetivo de esta investigación es realizar una revisión sistemática de las investigaciones sobre voluntariado que hayan usado el VFI de Clary et al. (1998). Método: 48 investigaciones, con 67 muestras independientes, cumplían los criterios de elegibilidad. El total de la muestra de los estudios oscila entre 20.375 y 21.988 participantes, según el motivo analizado. Resultados: el factor Valores obtiene la mayor puntuación media en general y en cada tipo de voluntariado, las puntuaciones más bajas corresponden a los factores Mejora del Curriculum y Defensa del Yo. Los estudios realizados con muestras menores de 40 años de edad media obtienen puntuaciones mayores en las escalas de Mejora del Curriculum y Conocimiento. Los estudios con menos del 50 % de mujeres arrojan medias más altas en la escala Social que los estudios con más del 50 % de mujeres en la muestra. Todas las escalas muestran coeficientes de fiabilidad entre .78 y .84. Solo ocho artículos aportan datos sobre la fiabilidad de la escala total con una media de .90. De los 26 estudios que realizaron un análisis factorial, 18 confirman la estructura de seis factores original (AU)

Volunteer Functions Inventory: A systematic review.

The objective of this research study was to conduct a systematic review of the research on volunteers using Clary et al.’s VFI (1998). A total of 48 research studies including 67 independent samples met eligibility criteria. The total sample of the studies analyzed ranged from 20375 to 21988 participants, depending on the motivation analyzed. The results show that the Values factor obtained the highest mean score, both overall and in each type of volunteering, whereas the lowest scores were for the Career and Enhancement factors. Studies conducted with samples with a mean age under 40 years obtain higher scores on Career and Understanding scales when compared to studies in older samples. The group of studies with less than 50% women yield higher mean scores on the Social scale than studies with more than 50% women in the sample. All the scales show reliability coefficients between .78 and .84. Only eight of the articles provide data on the reliability of the scale with a mean value of .90. Of the 26 studies that performed factor analysis, 18 confirmed the original structure of six factors.

Three cases with L1 syndrome and two novel mutations in the L1CAM gene.

UNLABELLED: Mutations in the L1CAM gene have been identified in the following various X-linked neurological disorders: congenital hydrocephalus; mental retardation, aphasia, shuffling gait, and adducted thumbs (MASA) syndrome; spastic paraplegia; and agenesis of the corpus callosum. These conditions are currently considered different phenotypes of a single entity known as L1 syndrome. We present three families with L1 syndrome. Sequencing of the L1CAM gene allowed the identification of the following mutations involved: a known splicing mutation (c.3531-12G>A) and two novel ones: a missense mutation (c.1754A>C; p.Asp585Ala) and a nonsense mutation (c.3478C>T; p.Gln1160Stop). The number of affected males and carrier females identified in a relatively small population suggests that L1 syndrome may be under-diagnosed. CONCLUSION: L1 syndrome should be considered in the differential diagnosis of intellectual disability or mental retardation in children, especially when other signs such as hydrocephalus or adducted thumbs are present.

Infección por Plasmodium ovale: descripción de 16 casos y revisión del tema / Plasmodium ovale infection: description of 16 cases and a review

Introducción Existe poca información sobre la malaria por Plasmodium ovale importada. Método Se estudiaron retrospectivamente 16 casos. Resultados La mayoría presentó un periodo de incubación de 2 a 53 meses y eran africanos inmigrantes o residentes en España que viajaron a África occidental; 10 presentaban enfermedades de base y 5 sufrieron una infección previa por P. falciparum; 3 pacientes presentaron complicaciones graves y 3 estaban asintomáticos. El test rápido fue positivo en 2 de 10 pacientes. A 5 se diagnosticó únicamente con PCR. Conclusiones La infección por P. ovale puede ser asintomática o producir complicaciones graves hasta 5 años después del regreso (AU)

Introduction: Information on imported malaria caused by Plasmodium ovale parasite is scarce. Methods: Sixteen cases were studied retrospectively.Results: Most cases had an incubation period ranging from 2 to 53 months and were African immigrantsrecently arrived or residents in Spain who had visited West Africa. Ten patients had underlying diseasesand 5 suffered from a previous P. falciparum infection. Three patients had severe complications and 3 were asymptomatic. Rapid malaria test was positive in 2 out of 10 patients. Five were diagnosed onlywith PCR. Conclusions: P. ovale infection can be asymptomatic or cause severe complications up to 5 years afterarriving (AU)

[Plasmodium ovale infection: description of 16 cases and a review]. / Infección por Plasmodium ovale: descripción de 16 casos y revisión del tema.

INTRODUCTION: Information on imported malaria caused by Plasmodium ovale parasite is scarce. METHODS: Sixteen cases were studied retrospectively. RESULTS: Most cases had an incubation period ranging from 2 to 53 months and were African immigrants recently arrived or residents in Spain who had visited West Africa. Ten patients had underlying diseases and 5 suffered from a previous P. falciparum infection. Three patients had severe complications and 3 were asymptomatic. Rapid malaria test was positive in 2 out of 10 patients. Five were diagnosed only with PCR. CONCLUSIONS: P. ovale infection can be asymptomatic or cause severe complications up to 5 years after arriving.

Niño de 9 años con dolor abdominal crónico / Nine-year-old child with chronic abdominal pain

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Fiebre de origen desconocido y adenopatías retroperitoneales en mujer inmunocompetente / Fever and unknown origin and retroperitoneal adenopathies in immunocompetent woman

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