Four-channel self-compensating single-slope ADC for space environments

A multichannel high-resolution single-slope analogue-to-digital converter (SS ADC) is presented that automatically compensates for process, voltage and temperature variations, as well as for radiation effects, in order to be used in extreme environmental conditions. The design combines an efficient implementation by using a feedback loop that ensures an inherently monotonic and very accurate ramp generation, with high levels of configurability in terms of resolution and conversion rate, as well as input voltage range. The SS ADC was designed in a standard 0.35 μm CMOS technology. Experimental measurements of the performance and stability against radiation and temperature are presented to verify the proposed approach

A Front-End ASIC for a 3-D Magnetometer for Space Applications by Using Anisotropic Magnetoresistors

This paper presents an application-specific integrated circuit (ASIC) aimed for an alternative design of a digital 3-D magnetometer for space applications, with a significant reduction in mass and volume while maintaining a high sensitivity. The proposed system uses magnetic field sensors based on anisotropic magnetoresistances and a rad-hard mixed-signal ASIC designed in a standard 0.35 μm CMOS technology. The ASIC performs sensor-signal conditioning and analogue-to-digital conversion, and handles calibration tasks, system configuration, and communication with the outside. The proposed system provides high sensitivity to low magnetic fields, down to 3 nT, while offering a small and reliable solution under extreme environmental conditions in terms of radiation and temperature.Ministerio de Ciencia e Innovación AYA2011-29967-C05-05, AYA2009-14212-C05-04, AYA2008-06420-C04-0

Mortality of emergency abdominal surgery in high-, middle- and low-income countries

Background: Surgical mortality data are collected routinely in high-income countries, yet virtually no low- or middle-income countries have outcome surveillance in place. The aim was prospectively to collect worldwide mortality data following emergency abdominal surgery, comparing findings across countries with a low, middle or high Human Development Index (HDI). Methods: This was a prospective, multicentre, cohort study. Self-selected hospitals performing emergency surgery submitted prespecified data for consecutive patients from at least one 2-week interval during July to December 2014. Postoperative mortality was analysed by hierarchical multivariable logistic regression. Results: Data were obtained for 10 745 patients from 357 centres in 58 countries; 6538 were from high-, 2889 from middle- and 1318 from low-HDI settings. The overall mortality rate was 1⋅6 per cent at 24 h (high 1⋅1 per cent, middle 1⋅9 per cent, low 3⋅4 per cent; P < 0⋅001), increasing to 5⋅4 per cent by 30 days (high 4⋅5 per cent, middle 6⋅0 per cent, low 8⋅6 per cent; P < 0⋅001). Of the 578 patients who died, 404 (69⋅9 per cent) did so between 24 h and 30 days following surgery (high 74⋅2 per cent, middle 68⋅8 per cent, low 60⋅5 per cent). After adjustment, 30-day mortality remained higher in middle-income (odds ratio (OR) 2⋅78, 95 per cent c.i. 1⋅84 to 4⋅20) and low-income (OR 2⋅97, 1⋅84 to 4⋅81) countries. Surgical safety checklist use was less frequent in low- and middle-income countries, but when used was associated with reduced mortality at 30 days. Conclusion: Mortality is three times higher in low- compared with high-HDI countries even when adjusted for prognostic factors. Patient safety factors may have an important role. Registration number: NCT02179112 (http://www.clinicaltrials.gov)

Reproductive periods and larval abundance patterns of the crabs Panopeus africanus and Uca tangeri in a shallow inlet (SW Spain)

10 páginas, 7 figuras, 2 tablas.Adult females of Panopeus africanus A. Milne Edwards, 1867 and Uca tangeri (Eydoux, 1835) were sampled fortnightly from April 1989 to November 1991 in the Rio San Pedro inlet (SW Spain) to estimate the seasonal timing of their reproductive periods. Planktonic larvae were collected monthly from July 1991 to June 1992 by pumping during nocturnal flood and ebb spring tides to establish seasonal larval abundance patterns. Additional 24 h series of samples were collected in July 1991 and May/June 1992 to analyse larval abundance in relation to the main environmental cycles (diel, tidal and lunar phases, and vertical position in the water column). Both species showed a short, late-spring/summer reproductive period: mature and ovigerous females peaked from May to July. Seasonal occurrences of first zoea larvae also indicated short reproductive periods for both species. First zoea was the most abundant stage, representing 99.5% (P. africanus) and 99.9% (U. tangeri) of all individuals collected. On most sampling occasions, there was a net output of zoea I of both species from the inlet, suggesting that larvae are released in the inlet and exported to the bay. The abundance of the first zoea of P. africanus was higher during high and ebb tides, at night and at the surface of the water column. For this species, there was a significant interaction between lunar phase and diel phase: zoea I were most abundant during nocturnal neap tides. Zoea I of U. tangeri showed greater density at ebb tides; they were more abundant at the surface of the water column during ebb than at high tide, suggesting a vertical migration between these tidal phases. Considerable short-term (consecutive or alternate days) and long-term (interannual) variation in the abundance of larvae was observed for both species. The comparison of our results with the scarce information available on the reproductive periods and larval patterns of both species suggests that, at the northern limit of their latitudinal ranges, water temperature may control the seasonal timing of reproductive periods, but populations under different hydrodynamic regimes (different water conditions) might show peaks of larval release during different diel/tidal/lunar phases; this association of larval release with rhythmic cues may serve as a mechanism that may aid escape of larvae from unsuitable environmental conditions.This research was supported financially by Junta de Andalucía and Consejo Superior de Investigaciones Científicas.Peer reviewe

Estados juveniles de la ictiofauna en los caños de las salinas de la bahía de Cádiz

163 páginas, 203 figuras.El objetivo primordial del trabajo propuesto ha consistido en evaluar el potencial íctico de las especies de interés económico que existe en los caños de las salinas, determinando las épocas de presencia de los estados juveniles en los caños y los momentos de máxima abundancia, así como el estadío de desarrollo en que aparecen, el tamaño de los especímenes y sus hábitos alimentarios. La exposición de los resultados obtenidos se inicia con una aproximación global al área de estudio, describiendo sus rasgos geológicos, geográficos y climatológicos más significativos, y se analiza con cierto detalle la información hidrográfica existente sobre los caños, como habitat de los estados juveniles objeto de estudio. Asimismo, se describen los usos actuales a que están destinadas las marismas y salinas de la bahía, y se introducen términos y conceptos sobre su aprovechamiento en acuicultura, convenientes para una mejor comprensión de aspectos que se desarrollarán más adelante al tratar de las especies comerciales. La segunda parte del trabajo incluye los resultados específicos del estudio de los estados juveniles de la ictiofauna de los caños, con un primer apartado dedicado a la metodología, en el que se describe la estrategia, la técnica y los útiles de muestreo empleados para la captura de los estados juveniles, así como el posterior tratamiento de las muestras para la consecución de los objetivos previstos. Analizando de una manera general las principales características de la ictiofauna, señalando la composición de especies, su distribución en el área de estudio, las variaciones anuales de la abundancia de estados juveniles, la composición de tallas y los hábitos alimentarios del conjunto de especies recolectadas. Con un apartado final que se dedica a la exposición detallada de la información obtenida de cada una de las 48 especies recolectadas, acompañada de dibujos originales de los principales estados del desarrollo encontrados y de gráficas sobre la abundancia, distribución de tallas y composición de la alimentación.Proyecto de investigación AC 25/84-02, titulado "Estudio de alevinaje de peces marinos comerciales en los esteros de las salinas de la Ribera Gaditana", financiado por la Comisión Asesora de Investigación Científica y Técnica (CAICYT) y por el CSIC.Peer reviewe

Distribution and production of the polychaete Nereis diversicolor in a shallow coastal lagoon in the Bay of Cádiz (SW Spain)

10 páginas, 5 figuras, 5 tablas.[EN] The temporal and spatial distribution and production of Nereis diversicolor in a semi-natural lagoon system were studied by taking monthly samples at 4 sites during two years. The numerical abundance and biomass, with mean annual estimates of 1886 ind.m-2 and 4.6 g AFDW. m-2 respectively for the whole studied system, showed considerable interseason and intersite variations. The lowest N. diversicolor density was recorded at the most confined lagoonal area. Seasonal patterns for the numerical abundance, although showing sorne differences among sites, had main annual peaks in late autumn-early winter and in late spring-early summer. The studied population showed a prolonged recruitment period, with maxima in late spring and late autumn, and overlapping cohorts. The growth in width, with annual mean growth rates between 0.008 and 0.010 mm d-l , showed considerable seasonal oscillations. Using the size-frequency method, the mean annual production and productionlbiomass ratio (PIB) for the system were estimated to be 22.7 g AFDW. m-2 • yr-l and 4.9 respectively[FR] L'évolution temporelle, la distribution spatiale et la production de Nereis diversicolor ont été étudiées dans une lagune littorale, en prélevant des échantillons chaque mois, pendant deux années, dans quatre stations différentes. La densité et la biomasse, avec des valeurs moyennes de 1886 ind. m-2 et de 4,6 g poids sec sans cendres. m-2 respectivement, montrent une importante variation saisonnière et aussi une variation selon les différentes zones de la lagune. Les valeurs les plus basses ont été trouvées dans la zone la plus confinée. L'évolution saisonnière de la densité montre deux pics, l'un à la fin de l'automne-début de l'hiver et l'autre à la fin du printemps-début de l'été, mais il y a des différences entre les zones. La période de recrutement est très longue, avec cependant un maxima à la fin du printemps et un autre en automne. Plusieurs cohortes coexistent durant la plus grande partie de l'année. La croissance en largeur, avec des taux moyens annuels de 0,008 à 0,010 mm d-1, montre une importante variation saisonnière. La production moyenne annuelle pour toute la lagune a été estimée à 22,7 g de poids sec sans cendres. m-2 et le rapport production/biomasse (PIB) à 4,9.This research was supported financially by Comisión Asesora de Investigación Científica y Técnica (Project NAT91-1008) and Consejo Superior de Investigaciones Científicas.Peer reviewe

The effect of aquaculture practices on the benthic macroinvertebrate community of a lagoon system in the Bay of Cádiz (southwestern Spain)

12 páginas, 4 figuras, 5 tablas.Monthly quantitative Ekman-Birge grab sampling was used to characterize and compare the composition and structure of the benthic macroinvertebrate community inhabiting semi-enclosed polyculture lagoons (SPL) (three sampling sites) and enclosed monoculture ponds (EMP) (two sampling sites) of a lagoonal system of the Bay of Cádiz. The two areas differed considerably in habitat characteristics and aquaculture management. The SPL area was characterized by low rates of water exchange, low fish densities, and the presence of a macroalgal cover. In the EMP area, there was a complete exchange of water daily (by pumping) and a supply of food pellets, density of fish was high, and no vegetative cover was present. There were considerable differences in species composition between habitats with different culture methods: 11 of the 21 most abundant species were exclusive to one or the other. Several epibenthic species were abundant in the polyculture lagoon but were low in density or were absent in monoculture ponds. Some infaunal species, on the other hand, were more abundant in the monoculture ponds. Univeriate measures of community structure (abundance and biomass, Margalef’s species richness, Shannon-Wiener diversity, and Pielou’s evenness indices) did not indicate significant differences between the SPL and EMP areas. Conversely, the abundance-biomass comparison (ABC) method indicated that, on average, the macrobenthic community was moderately disturbed in the SPL and undisturbed in the EMP areas. Multidimensional scaling (MDS) ordination and hierarchical cluster analysis (Bray-Curtis similarity measure) revealed the occurrence of two main benthic assemblages that corresponded to the aquaculture methods. The different rates of water exchange for the two aquaculture practices seem to have contributed to differences in the composition and structure of the benthic communities.This research was supported financially by Comisión Asesora de Investigación Científica y Técnica (NAT91-1008 Project), Consejo Superior de Investigaciones Científicas, and Junta de Andalucía.Peer reviewe

Contribution to the knowledge of the hyperbenthic and epibenthic macrofauna of the tidal channels of the Bay of Cádiz (southern Spain)

9 páginas, 2 figuras, 3 tablas. IX Simposio Ibérico de Estudios del Bentos Marino (19-23 de febrero, 1996. Alcalá de Henares, Madrid, España) Ed. José M. Viéitez y Juan Junoy.La comunidad de macroinvertebrados bentónicos de los caños mareales de la bahía de Cádiz fue estudiada mediante la recogida de muestras quincenales en siete estaciones diferentes, durante dos años en la mayoría de los casos. Para cada año y estación de muestreo, se estimó la composición de especies y la frecuencia de ocurrencia de cada una de ellas. Las especies más frecuentemente capturadas son especies supra y epibéntonicas, muy eurihalinas y abundantes en los estuarios: el misidáceo Mesopodopsis slabberi (Van Bened, 1861) en el 81% de las muestras; el gasterópodo Hydrobia ulvae (Pennant, 1777) en el 78%; el decápodo Palaemonetes varians (Leach, 1814) en el 58%; los anfipodos Corophium multsetosum, Stock, 1952 en el 45% y Microdeutopus gryllotalpa Costa, 1853 en el 37%; y el isópodo Paragnathia formica (Hesse, 1864) en el 39% de las muestras. La variabilidad espacial de la comunidad fue más importante que la variabilidad interanual y mostró cierta relación con la profundidad de los caños estudiados. Por el contrario, el grado de aislamiento respecto al mar, la velocidad de la corriente y la salinidad en cada caño no guardaron relación con la variablidiad observada para la comunidad. A nivel de presencia-ausencia de las especies y en períodos de un año, la comunidad estudiada se mostró como persistente en los caños mareales interiores de la bahía de Cádiz.Peer reviewe

First record of the blue crab Callinectes exasperatus (Decapoda, Brachyura, Portunidae) for European waters

This paper is the first record of the blue crab, Callinectes exasperatus, in European waters and the first record for this species out of its natural distribution. Due to the similar morphology with Callinectes sapidus, a widely extended invader in the Atlantic, Mediterranean and Pacific waters, the initial determination based on morphological characters was further confirmed by DNA barcode analysis. A possible introduction vector is also discussed.The molecular analysis was carried out under funding from the project MEGALOPADN (CGL2009-11225), funded by the ‘Ministerio de Economía y Competitividad (MINECO)’ Spanish Plan R+D+I and FEDER.Peer reviewe

On the Occurrence of Afropinnotheres monodi Manning, 1993 (Decapoda: Pinnotheridae) in European Waters

3 páginas, 2 figuras, 1 tabla.Heretofore, the pinnotherid crab, Afropinnotheres monodi, had been recorded only from African waters. The range is now extended into European waters with discovery of material in the Gulf of Cádiz. Furthermore, early collections of material had occurred only in open water; now three hosts can be assigned, the clams Scrobicularia plana, Ruditapes decussatus and Cerastoderma glaucum. Further discoveries of this pinnotherid may now be expected, especially along the coast of Portugal.For financial support we want to thank Junta de Andalucía PAIDI (Plan Andaluz de Investigacion Desarrollo e Innovacion), for funding to groups RNM 108 and RNM 141.Peer reviewe