bluuebunny/crossref_metadata_2025 huggingface dataset:
Top-down estimation of carbon monoxide emissions from the Mexico Megacity based on FTIR measurements from ground and space
Authors: Stremme W. , Grutter M. , Rivera C. , Bezanilla A. , Garcia A. R. , Ortega I. , George M. , Clerbaux C. , Coheur P.-F. , Hurtmans D. , Hannigan J. W. , Coffey M. T.
Published: February 2013

Abstract. Continuous carbon monoxide (CO) total column densities above the Universidad Nacional Autónoma de México (UNAM) campus in Mexico City have been derived from solar absorption infrared spectroscopic measurements since October 2007. Its diurnal evolution is used in the present study in conjunction with other ground-based and satellite data to develop a top-down emission estimate of the annual CO emission of the Mexico City Metropolitan Area (MCMA). The growth-rate of the total column around noon under low ventilation conditions is calculated and allows us to derive the average surface emission-flux at UNAM, while similar measurements taken at the edge of the MCMA in Tecámac provide information on background CO levels in the Mexico basin. Based on 3 yr of measurements, CO column measurements from the Infrared Atmospheric Sounding Interferometer (IASI) satellite instrument are used to reconstruct the spatial distribution of this anthropogenic pollutant over the MCMA. The agreement between the measured columns of the satellite and ground-based measurements is excellent, particularly when a comparison strategy based on time-displaced air masses is used. The annual emission of the Mexico Megacity is estimated to be (2.15 ± 0.5) Tg yr−1 for the year 2008, while the official inventory for that year reported 1.6 Tg yr−1. The difference is slightly higher than the conservative uncertainty estimated in this work suggesting that the emission might be underestimated by the conventional bottom-up method. A larger discrepancy is found in the spatial distribution of the emissions, when comparing the emission flux over UNAM (derived from the ground-based measurement) with that of the inventory integrated over a representative area. The methodology presented here represents a new and useful strategy to evaluate the contribution of megacities to the global anthropogenic gas emissions. Additionally, three different strategies to compare ground and space-based measurements above an inhomogeneous and strongly contaminated area like Mexico City are presented and discussed.
Quality assessment of Automatic Dependent Surveillance Contract (ADS-C) wind and temperature observation from commercial aircraft
Authors: de Haan S. , Bailey L. J. , Können J. E.
Published: February 2013

Abstract. Aircraft observations of wind and temperature are very important for upper air meteorology. In this article, the quality of the meteorological information of an Automatic Dependent Surveillance-Contract (ADS-C) message is assessed. The ADS-C messages broadcast by the aircraft are received at air traffic control centres for surveillance and airline control centres for general aircraft and dispatch management. A comparison is performed against a global numerical prediction (NWP) model and wind and temperature observations derived from Enhanced Surveillance (EHS) air-traffic control radar which interrogates all aircraft in selective mode (Mode-S EHS). Almost 16 000 ADS-C reports with meteorological information were compiled from the Royal Dutch Airlines (KLM) database. The length of the data set is 76 consecutive days and started on 1 January 2011. The wind and temperature observations are of good quality when compared to the global NWP forecast fields from the European Centre for Medium-Range Weather Forecasts (ECMWF). Comparison of ADS-C wind and temperature observations against Mode-S EHS derived observations in the vicinity of Amsterdam Airport Schiphol shows that the wind observations are of similar quality and the temperature observations of ADS-C are of better quality than those from Mode-S EHS. However, the current ADS-C data set has a lower vertical resolution than Mode-S EHS. High vertical resolution can be achieved by requesting more ADS-C when aircraft are ascending or descending, but could result in increased data communication costs.
Improved mixing height monitoring through a combination of lidar and radon measurements
Authors: Griffiths A. D. , Parkes S. D. , Chambers S. D. , McCabe M. F. , Williams A. G.
Published: February 2013

Abstract. Surface-based radon (222Rn) measurements can be combined with lidar backscatter to obtain a higher quality time series of mixing height within the planetary boundary layer (PBL) than is possible from lidar alone, and a more quantitative measure of mixing height than is possible from only radon. The reason why lidar measurements are improved is that there are times when lidar signals are ambiguous, and reliably attributing the mixing height to the correct aerosol layer presents a challenge. By combining lidar with a mixing length scale derived from a time series of radon concentration, automated and robust attribution is possible during the morning transition. Radon measurements provide mixing information during the night, but concentrations also depend on the strength of surface emissions. After processing radon in combination with lidar, we obtain nightly measurements of radon emissions and are able to normalise the mixing length scale for changing emissions. After calibration with lidar, the radon-derived equivalent mixing height agrees with other measures of mixing on daily and hourly timescales and is a potential method for studying intermittent mixing in nocturnal boundary layers.
Assessment of the CALIPSO Lidar 532 nm version 3 lidar ratio models using a ground-based lidar and AERONET sun photometers in Brazil
Authors: Lopes F. J. S. , Landulfo E. , Vaughan M. A.
Published: February 2013

Abstract. Since the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO) satellite first began probing the Earth's atmosphere on 13 June 2006, several research groups dedicated to investigating the atmosphere's optical properties have conducted measurement campaigns to validate the CALIPSO data products. Recently, in order to address the lack of CALIPSO validation studies in the Southern Hemisphere, and especially the South American continent, the Lasers Environmental Applications Research Group at Brazil's Nuclear and Energy Research Institute (IPEN) initiated efforts to assess CALIPSO's aerosol lidar ratio estimates using two ground-based remote sensing instruments: a single elastic backscatter lidar system and the AERONET sun photometers installed at five different locations in Brazil. In this study we develop a validation methodology to assess the accuracy of the modeled values of the lidar ratios used by the CALIPSO extinction algorithms. We recognize that the quality of any comparisons between satellite and ground-based measurements depends on the degree to which the instruments are collocated, and that even selecting the best spatial and temporal matches does not provide an unequivocal guarantee that both instruments are measuring the same air mass. The validation methodology presented in this study therefore applies backward and forward air mass trajectories in order to obtain the best possible match between the air masses sampled by the satellite and the ground-based instruments, and thus reduces the uncertainties associated with aerosol air mass variations. Quantitative comparisons of lidar ratio values determined from the combination of AERONET optical depth measurements and CALIOP integrated attenuated backscatter show good agreement with the model values assigned by the CALIOP algorithm. These comparisons yield a mean percentage difference of −2% ± 26%. Similarly, lidar ratio values retrieved by the elastic backscatter lidar system at IPEN show a mean percentage difference of −2% ± 15% when compared with CALIOP's lidar ratio. These results confirm the accuracy in the lidar ratio estimates provided by the CALIOP algorithms to within an uncertainty range of no more than 30%.
Modeling benthic–pelagic nutrient exchange processes and porewater distributions in a seasonally hypoxic sediment: evidence for massive phosphate release by Beggiatoa?
Authors: Dale A. W. , Bertics V. J. , Treude T. , Sommer S. , Wallmann K.
Published: February 2013

Abstract. This study presents benthic data from 12 samplings from February to December 2010 in a 28 m deep channel in the southwest Baltic Sea. In winter, the distribution of solutes in the porewater was strongly modulated by bioirrigation which efficiently flushed the upper 10 cm of sediment, leading to concentrations which varied little from bottom water values. Solute pumping by bioirrigation fell sharply in the summer as the bottom waters became severely hypoxic (< 2 μM O2). At this point the giant sulfide-oxidizing bacteria Beggiatoa was visible on surface sediments. Despite an increase in O2 following mixing of the water column in November, macrofauna remained absent until the end of the sampling. Contrary to expectations, metabolites such as dissolved inorganic carbon, ammonium and hydrogen sulfide did not accumulate in the upper 10 cm during the hypoxic period when bioirrigation was absent, but instead tended toward bottom water values. This was taken as evidence for episodic bubbling of methane gas out of the sediment acting as an abiogenic irrigation process. Porewater–seawater mixing by escaping bubbles provides a pathway for enhanced nutrient release to the bottom water and may exacerbate the feedback with hypoxia. Subsurface dissolved phosphate (TPO4) peaks in excess of 400 μM developed in autumn, resulting in a very large diffusive TPO4 flux to the water column of 0.7 ± 0.2 mmol m−2 d−1. The model was not able to simulate this TPO4 source as release of iron-bound P (Fe–P) or organic P. As an alternative hypothesis, the TPO4 peak was reproduced using new kinetic expressions that allow Beggiatoa to take up porewater TPO4 and accumulate an intracellular P pool during periods with oxic bottom waters. TPO4 is then released during hypoxia, as previous published results with sulfide-oxidizing bacteria indicate. The TPO4 added to the porewater over the year by organic P and Fe–P is recycled through Beggiatoa, meaning that no additional source of TPO4 is needed to explain the TPO4 peak. Further experimental studies are needed to strengthen this conclusion and rule out Fe–P and organic P as candidate sources of ephemeral TPO4 release. A measured C/P ratio of < 20 for the diffusive flux to the water column during hypoxia directly demonstrates preferential release of P relative to C under oxygen-deficient bottom waters. This coincides with a strong decrease in dissolved inorganic N/P ratios in the water column to ~ 1. Our results suggest that sulfide oxidizing bacteria could act as phosphorus capacitors in systems with oscillating redox conditions, releasing massive amounts of TPO4 in a short space of time and dramatically increasing the internal loading of TPO4 to the overlying water.
Organic molecular composition of marine aerosols over the Arctic Ocean in summer: contributions of primary emission and secondary aerosol formation
Authors: Fu P. Q. , Kawamura K. , Chen J. , Charrière B. , Sempéré R.
Published: February 2013

Abstract. Organic molecular composition of marine aerosol samples collected during the MALINA cruise in the Arctic Ocean was investigated by gas chromatography/mass spectrometry. More than 110 individual organic compounds were determined in the samples and were grouped into different compound classes based on the functionality and sources. The concentrations of total quantified organics ranged from 7.3 to 185 ng m−3 (mean 47.6 ng m−3), accounting for 1.8–11.0% (4.8%) of organic carbon in the marine aerosols. Primary saccharides were found to be dominant organic compound class, followed by secondary organic aerosol (SOA) tracers formed from the oxidation of biogenic volatile organic compounds (VOCs) such as isoprene, α-pinene and β-caryophyllene. Mannitol, the specific tracer for airborne fungal spores, was detected as the most abundant organic species in the samples with a concentration range of 0.052–53.3 ng m−3 (9.2 ng m−3), followed by glucose, arabitol, and the isoprene oxidation products of 2-methyltetrols. Biomass burning tracers such as levoglucosan are evident in all samples with trace levels. On the basis of the tracer-based method for the estimation of fungal-spore OC and biogenic secondary organic carbon (SOC), we estimate that an average of 10.7% (up to 26.2%) of the OC in the marine aerosols was due to the contribution of fungal spores, followed by the contribution of isoprene SOC (mean 3.8%) and α-pinene SOC (2.9%). In contrast, only 0.19% of the OC was due to the photooxidation of β-caryophyllene. This study indicates that primary organic aerosols from biogenic emissions, both from long-range transport of mid-latitude aerosols and from sea-to-air emission of marine organics, as well as secondary organic aerosols formed from the photooxidation of biogenic VOCs are important factors controlling the organic chemical composition of marine aerosols in the Arctic Ocean.
Effects of temperature on the metabolic stoichiometry of Arctic zooplankton
Authors: Alcaraz M. , Almeda R. , Saiz E. , Calbet A. , Duarte C. M. , Agustí S. , Santiago R. , Alonso A.
Published: February 2013

Abstract. We assessed the relationship between zooplankton metabolism (respiration and inorganic N and P excretion) and "in situ" temperature through a grid of stations representing a range of natural temperature variation during the ATOS-Arctic cruise (July 2007). The objective was to explore not only the direct effects of temperature on zooplankton carbon respiratory losses (hereafter CR) and NH4-N and PO4-P excretion rates (hereafter NE and PE, respectively), but also to investigate whether these metabolic pathways responded similarly to temperature, and so how temperature could affect the stoichiometry of the metabolic products. Metabolic rates, normalised to per unit of zooplankton carbon biomass, increased with increasing temperature following the Arrhenius equation. However, the activation energy differed for the various metabolic processes considered. Respiration, CR, was the metabolic activity least affected by temperature, followed by NE and PE, and as a consequence the values of the CR : NE, CR : PE and NE : PE atomic quotients were inversely related to temperature. The effects of temperature on the stoichiometry of the excreted N and P products would contribute to modifying the nutrient pool available for phytoplankton and induce qualitative and quantitative shifts in the size, community structure and chemical composition of primary producers that could possibly translate to the whole Arctic marine food web.
Benthic buffers and boosters of ocean acidification on coral reefs
Authors: Anthony K. R. N. , Diaz-Pulido G. , Verlinden N. , Tilbrook B. , Andersson A. J.
Published: February 2013

Abstract. Ocean acidification is a threat to marine ecosystems globally. In shallow-water systems, however, ocean acidification can be masked by benthic carbon fluxes, depending on community composition, seawater residence time, and the magnitude and balance of net community production (pn) and calcification (gn). Here, we examine how six benthic groups from a coral reef environment on Heron Reef (Great Barrier Reef, Australia) contribute to changes in seawater aragonite saturation state (Ωa). Results of flume studies showed a hierarchy of responses across groups, depending on CO2 level, time of day and water flow. At low CO2 (350–450 μatm), macroalgae (Chnoospora implexa), turfs and sand elevated Ωa of the flume water by around 0.10 to 1.20 h−1 – normalised to contributions from 1 m2 of benthos to a 1 m deep water column. The rate of Ωa increase in these groups was doubled under acidification (560–700 μatm) and high flow (35 compared to 8 cm s−1). In contrast, branching corals (Acropora aspera) increased Ωa by 0.25 h−1 at ambient CO2 (350–450 μatm) during the day, but reduced Ωa under acidification and high flow. Nighttime changes in Ωa by corals were highly negative (0.6–0.8 h−1) and exacerbated by acidification. Calcifying macroalgae (Halimeda spp.) raised Ωa by day (by around 0.13 h−1), but lowered Ωa by a similar or higher amount at night. Analyses of carbon flux contributions from four different benthic compositions to the reef water carbon chemistry across Heron Reef flat and lagoon indicated that the net lowering of Ωa by coral-dominated areas can to some extent be countered by long water residence times in neighbouring areas dominated by turfs, macroalgae and potentially sand.
Saturated CO2 inhibits microbial processes in CO2-vented deep-sea sediments
Authors: de Beer D. , Haeckel M. , Neumann J. , Wegener G. , Inagaki F. , Boetius A.
Published: February 2013

Abstract. This study focused on biogeochemical processes and microbial activity in sediments of a natural deep-sea CO2 seepage area (Yonaguni Knoll IV hydrothermal system, Japan). The aim was to assess the influence of the geochemical conditions occurring in highly acidic and CO2 saturated sediments on sulphate reduction (SR) and anaerobic methane oxidation (AOM). Porewater chemistry was investigated from retrieved sediment cores and in situ by microsensor profiling. The sites sampled around a sediment-hosted hydrothermal CO2 vent were very heterogeneous in porewater chemistry, indicating a complex leakage pattern. Near the vents, droplets of liquid CO2 were observed to emanate from the sediments, and the pH reached approximately 4.5 in a sediment depth >6 cm, as determined in situ by microsensors. Methane and sulphate co-occurred in most sediment samples from the vicinity of the vents down to a depth of at least 3 m. However, SR and AOM were restricted to the upper 7–15 cm below seafloor, although neither temperature, low pH, nor the availability of methane and sulphate could be limiting microbial activity. We argue that the extremely high subsurface concentrations of dissolved CO2 (1000–1700 mM), through the ensuing high H2CO3 levels (approx. 1–2 mM) uncouples the proton-motive-force (PMF) and thus inhibits biological energy conservation by ATPase-driven phosphorylation. This limits life to the surface sediment horizons above the liquid CO2 phase, where less extreme conditions prevail. Our results may have to be taken into consideration in assessing the consequences of deep-sea CO2 sequestration on benthic element cycling and on the local ecosystem state.
An educational model for ensemble streamflow simulation and uncertainty analysis
Authors: AghaKouchak A. , Nakhjiri N. , Habib E.
Published: February 2013

Abstract. This paper presents the hands-on modeling toolbox, HBV-Ensemble, designed as a complement to theoretical hydrology lectures, to teach hydrological processes and their uncertainties. The HBV-Ensemble can be used for in-class lab practices and homework assignments, and assessment of students' understanding of hydrological processes. Using this modeling toolbox, students can gain more insights into how hydrological processes (e.g., precipitation, snowmelt and snow accumulation, soil moisture, evapotranspiration and runoff generation) are interconnected. The educational toolbox includes a MATLAB Graphical User Interface (GUI) and an ensemble simulation scheme that can be used for teaching uncertainty analysis, parameter estimation, ensemble simulation and model sensitivity. HBV-Ensemble was administered in a class for both in-class instruction and a final project, and students submitted their feedback about the toolbox. The results indicate that this educational software had a positive impact on students understanding and knowledge of uncertainty in hydrological modeling.
A universal calibration function for determination of soil moisture with cosmic-ray neutrons
Authors: Franz T. E. , Zreda M. , Rosolem R. , Ferre T. P. A.
Published: February 2013

Abstract. A cosmic-ray soil moisture probe is usually calibrated locally using soil samples collected within its support volume. But such calibration may be difficult or impractical, for example when soil contains stones, in presence of bedrock outcrops, in urban environments, or when the probe is used as a rover. Here we use the neutron transport code MCNPx with observed soil chemistries and pore water distribution to derive a universal calibration function that can be used in such environments. Reasonable estimates of pore water content can be made from neutron intensity measurements and by using measurements of the other hydrogen pools (water vapor, soil lattice water, soil organic carbon, and biomass). Comparisons with independent soil moisture measurements at one cosmic-ray probe site and, separately, at 35 sites, show that the universal calibration function explains more than 79% of the total variability within each dataset, permitting accurate isolation of the soil moisture signal from the measured neutron intensity signal. In addition the framework allows for any of the other hydrogen pools to be separated from the neutron intensity measurements, which may be useful for estimating changes in biomass, biomass water, or exchangeable water in complex environments.
Assessing the predictive capability of randomized tree-based ensembles in streamflow modelling
Authors: Galelli S. , Castelletti A.
Published: February 2013

Abstract. Combining randomization methods with ensemble prediction is emerging as an effective option to balance accuracy and computational efficiency in data-driven modeling. In this paper we investigate the prediction capability of extremely randomized trees (Extra-Trees), in terms of accuracy, explanation ability and computational efficiency, in a streamflow modeling exercise. Extra-Trees are a totally randomized tree-based ensemble method that (i) alleviates the poor generalization property and tendency to overfitting of traditional standalone decision trees (e.g. CART); (ii) is computationally very efficient; and, (iii) allows to infer the relative importance of the input variables, which might help in the ex-post physical interpretation of the model. The Extra-Trees potential is analyzed on two real-world case studies (Marina catchment (Singapore) and Canning River (Western Australia)) representing two different morphoclimatic contexts comparatively with other tree-based methods (CART and M5) and parametric data-driven approaches (ANNs and multiple linear regression). Results show that Extra-Trees perform comparatively well to the best of the benchmarks (i.e. M5) in both the watersheds, while outperforming the other approaches in terms of computational requirement when adopted on large datasets. In addition, the ranking of the input variable provided can be given a physically meaningful interpretation.
A combined approach of remote sensing and airborne electromagnetics to determine the volume of polynya sea ice in the Laptev Sea
Authors: Rabenstein L. , Krumpen T. , Hendricks S. , Koeberle C. , Haas C. , Hoelemann J. A.
Published: February 2013

Abstract. A combined interpretation of synthetic aperture radar (SAR) satellite images and helicopter electromagnetic (HEM) sea-ice thickness data has provided an estimate of sea-ice volume formed in Laptev Sea polynyas during the winter of 2007/08. The evolution of the surveyed sea-ice areas, which were formed between late December 2007 and middle April 2008, was tracked using a series of SAR images with a sampling interval of 2–3 days. Approximately 160 km of HEM data recorded in April 2008 provided sea-ice thicknesses along profiles that transected sea-ice varying in age from 1–116 days. For the volume estimates, thickness information along the HEM profiles was extrapolated to zones of the same age. The error of areal mean thickness information was estimated to be between 0.2 m for younger ice and up to 1.55 m for older ice, with the primary error source being the spatially limited HEM coverage. Our results have demonstrated that the modal thicknesses and mean thicknesses of level ice correlated with the sea-ice age, but that varying dynamic and thermodynamic sea-ice growth conditions resulted in a rather heterogeneous sea-ice thickness distribution on scales of tens of kilometers. Taking all uncertainties into account, total sea-ice area and volume produced within the entire surveyed area were 52 650 km2 and 93.6 ± 26.6 km3. The surveyed polynya contributed 2.0 ± 0.5% of the sea-ice produced throughout the Arctic during the 2007/08 winter. The SAR-HEM volume estimate compares well with the 112 km3 ice production calculated with a high resolution ocean sea-ice model. Measured modal and mean-level ice thicknesses correlate with calculated freezing-degree-day thicknesses with a factor of 0.87–0.89, which was too low to justify the assumption of homogeneous thermodynamic growth conditions in the area, or indicates a strong dynamic thickening of level ice by rafting of even thicker ice.
Comparación de las tasas de respuesta en el uso combinado de modalidades de encuesta
Authors: Díaz de Rada Igúzquiza Vidal , Palacios Gómez Jose Luís
Published: February 2013

El propósito de este trabajo es analizar la estructura de las tasas derespuesta de las dos modalidades de encuesta combinadas en unestudio de comportamientos y hábitos deportivos en un gran municipiode Madrid. Se expone la evolución de las tasas de respuesta a lo largodel proceso de encuesta con entrevistas presenciales y con entrevistastelefónicas, considerando los posibles factores que pudiesen infl uir enlas diferencias encontradas. Los resultados muestran que las diferenciasobservadas en las tasas de respuesta dependen de la modalidadde encuesta utilizada y que la encuesta telefónica presenta un mejorfuncionamiento comparado que la encuesta presencial.
La nacionalización electoral de los partidos políticos en España
Authors: Simón Cosano Pablo
Published: February 2013

Este estudio se centra en la nacionalización de los partidos en Españaentendida como la homogeneidad en los apoyos electorales que consigueun partido en las circunscripciones de una elección nacional. La primeraparte del artículo presenta una descripción de la evolución de la nacionalizacióndesde 1977 hasta la actualidad y muestra cómo el sistema departidos español está cada vez más nacionalizado pese a sus diferenciasentre partidos. En la segunda parte se busca explicar sus determinantes. Elanálisis indica que los votos que reciba el partido a nivel nacional incrementanla nacionalización de los partidos. La antigüedad solo potencia lanacionalización si el partido es de ámbito estatal mientras que para lospartidos subnacionales esta variable tiene un efecto negativo, apuntando aun trade-off entre ambos grupos. Finalmente, la distancia en el ejeizquierda-derecha reduce la homogeneidad electoral de los partidosnacionales mientras que las elecciones fundacionales no tienen efecto.
¿Influyen las políticas autonómicas en la utilización de la excedencia por cuidado de hijos?
Authors: Lapuerta Irene
Published: February 2013

Este artículo analiza el impacto de las políticas implementadas porcinco Comunidades Autónomas —Navarra, Castilla y León, País Vasco,Castilla-La Mancha y La Rioja— en la utilización de la excedencia porcuidado de hijos. Para ello, se plantea un diseño de investigacióncuasiexperimental, conocido con el nombre de «dobles diferencias»(difference-in-difference). La investigación está basada en unasubmuestra extraída de la Muestra Continua de Vidas Laborales (año2006), compuesta por 94.493 personas que eran titulares del derecho ala excedencia en el periodo 1996-2006. Los resultados refl ejan unefecto positivo de las medidas implementadas por Navarra y Castilla yLeón y confi rman la relevancia de la cuantía económica frente a otrascaracterísticas en su diseño. Sin embargo, ninguna de las políticas tieneincidencia en el uso de la excedencia por parte de los hombres, inclusoen el caso de aquellas Comunidades que han establecido discriminacionespositivas en su diseño.
Internet y competición electoral: el caso de Esquerra Republicana de Catalunya
Authors: Balcells Joan , Cardenal Izquierdo Ana Sofía
Published: February 2013

Este artículo contrasta la hipótesis de la igualación a nivel del voto.Numerosos estudios han analizado si Internet está nivelando el campode juego de la competición electoral al ofrecer a los partidos pequeñosoportunidades para aumentar su visibilidad. Para testar la infl uencia deluso de Internet en el voto, se analiza el comportamiento de los votantesde ERC. Haciendo uso de datos de encuesta, testamos si la exposicióna información política online ha tenido algún efecto en su opción devoto. Los resultados muestran que la exposición a la campaña onlineaumenta la probabilidad de votar a Solidaritat Catalana respecto a votarde nuevo por ERC. El análisis apoya la idea de que Internet actúa comoun entorno mediático diferenciado donde los mensajes políticoscompiten en términos de mayor igualdad.
Regímenes de bienestar y valores en Europa
Authors: Calzada Gutiérrez Inés , Gómez Garrido Maria , Moreno Fernández Luis , Moreno Fuentes Francisco Javier
Published: February 2013

En este artículo se analiza la relación entre la distribución de valores enla ciudadanía de los países europeos, y los equilibrios institucionales delos sistemas de protección social de los diferentes países según loconceptualizado por las tipologías de los regímenes de bienestar máscomúnmente utilizadas. Tras analizar la distribución de los valores enEuropa, y medir su efecto sobre las actitudes hacia el bienestar en losdiferentes regímenes de bienestar, se comprueba que dichos valores nose distribuyen siguiendo los límites de la tipología básica de estosregímenes. El estudio de las actitudes favorables a la intervención delEstado en el ámbito de las políticas de protección social a través de unmodelo de regresión multinivel muestra, sin embargo, la existencia decaracterísticas diferenciales en el apoyo a dichos regímenes debienestar en cada país, dando lugar a la agregación de determinadosvalores específi cos en cada uno de dichos regímenes.
Endeudamiento estudiantil y acceso a la eduación superior en Chile
Authors: Olavarría Gambi Mauricio , Allende González Claudio
Published: February 2013

Este trabajo analiza si el temor al endeudamiento, por cursar estudiospostsecundarios, afecta las decisiones de postulación e ingreso de potencialesestudiantes a la educación superior, si hay relación entre el temor alendeudamiento y el nivel socioeconómico de las familias a las que pertenecenlos potenciales estudiantes, y si hay asociación entre el temor al endeudamientoy el rendimiento escolar. El trabajo muestra que el temor alendeudamiento para cursar estudios superiores no sería una limitante paraque jóvenes de sectores populares accedieran a la educación de tercer ciclo.El estudio también indica que la disponibilidad de crédito favorece el acceso ala educación superior. Los hallazgos de este estudio contradicen las conclusionesde los trabajos de Claire Callender y Jonathan Jackson, quienespreviamente y con los mismos propósitos analizaron el caso británico.
Spatial Learning and Memory—What's TLE Got to Do with It?
Authors: Murphy Geoffrey G.
Published: February 2013

Cognitive impairment is a significant comorbidity of epilepsy. At present, the molecular/cellular mechanisms that underlie these cognitive impairments remain unknown. It seems likely that a complete understanding at the molecular/cellular level will require the use of rodent models. A number of rodent models of epilepsy are used to study cognition in a variety of behavioral tasks. This review presents a brief overview of two commonly used tasks (the Morris water maze and the radial arm maze) that have been used to assess spatial learning/memory in two chemoconvulsant models of temporal lobe epilepsy.
The Consequences of Social Processes: Aggregate Populations, Projectile Point Accumulation, and Subsistence Patterns in the American Southwest
Authors: Arakawa Fumiyasu , Nicholson Christopher , Rasic Jeff
Published: February 2013

Tracking broad-scale behavioral patterns using both lithics and faunal remains offers one line of evidence for investigating both prehistoric subsistence activities and the consequences of aggregation and increases in population size. Accumulation research, which examines the ratio of projectile points to cooking pottery sherds from the same context, shows a higher ratio of projectile points in areas with lower population densities. This pattern holds true when examining faunal assemblages and large-game procurement practices from A.D. 900 to 1300 in southwestern Colorado and southeastern Utah. This research demonstrates that social processes such as aggregation and increases in population density influence human hunting strategies as much as changes in natural environment, which lead to changes in a group’s dietary regime.
The Allure of the Exotic: Reexamining the Use of Local and Distant Pipestone Quarries in Ohio Hopewell Pipe Caches
Authors: Emerson Thomas E. , Farnsworth Kenneth B. , Wisseman Sarah U. , Hughes Randall E.
Published: February 2013

Mary W. Helms’s observation that spatial distance often correlates with spiritual power has become an axiom in interpreting the role of exotic materials in societies. This is especially evident in explanations of the North American Hopewell Interaction Sphere. The circulation and accumulation of exotic materials in massive mortuary caches peaked during the Hopewell era (100 B.C. to A.D. 300). The premise that Hopewell smoking pipes were made in Ohio, primarily of local raw material, and circulated to foreign locations was an integral part of this interaction model. In this study we demonstrate, primarily using reflectance near-infrared spectroscopy (NIS), that early Hopewell Tremper Mound pipe raw-material acquisition focused on exotic pipestones from Illinois and Minnesota. By contrast, later Mound City cache pipes were almost exclusively made from local limestone and pipestone. The discovery of this shift in preference for and/or access to different quarry sources by Ohio Hopewell societies provides new perspectives on early Hopewell development and long-distance interaction.
Farming and Foraging at the Crossroads: The Consequences of Cherokee and European Interaction Through the Late Eighteenth Century
Authors: VanDerwarker Amber M. , Marcoux Jon B. , Hollenbach Kandace D.
Published: February 2013

The material remains of daily subsistence within Cherokee communities reflect strategies that households enacted while adapting to disruptions associated with European colonialism. Plant subsistence remains dating from the late Pre-Contact period through the end of the Revolutionary War (A.D. 1300–1783) reveal how Cherokee food producers! collectors fed their families as they navigated an increasingly uncertain landscape. Framing our analysis in terms of risk mitigation and future-discounting concepts from human behavioral ecology, we argue that Cherokee households responded to increasing risk and uncertainty by shifting towards subsistence strategies that had more immediate rewards. Although Cherokee plant subsistence remains exhibit continuity in how people farmed and foraged, our study shows that households made strategic decisions to alter their food production and collection with respect to looming uncertainty. Archaeobotanical analysis from multiple sites spanning the Colonial period (ca. A.D. 1670–1783) reveal a stepwise process of declining maize production, increased foraging, and overall diversification of the plant diet. This case underscores the relevance of concepts from human behavioral ecology to complex colonial situations by demonstrating that strategies of risk prevention and mitigation have applicability beyond ecological factors.
The Study of Indigenous Political Economies and Colonialism in Native California: Implications for Contemporary Tribal Groups and Federal Recognition
Authors: Lightfoot Kent G. , Panich Lee M. , Schneider Tsim D. , Gonzalez Sara L. , Russell Matthew A. , Modzelewski Darren , Molino Theresa , Blair Elliot H.
Published: February 2013

This article advocates for a comparative approach to archaeological studies of colonialism that considers how Native American societies with divergent political economies may have influenced various kinds of processes and outcomes in their encounters with European colonists. Three dimensions of indigenous political economies (polity size, polity structure, and landscape management practices) are identified as critical variables in colonial research. The importance of considering these dimensions is exemplified in a case study from California, which shows how small-sized polities, weak to moderate political hierarchies, and regionally oriented pyrodiversity economies played significant roles in the kinds of colonial relationships that unfolded. The case study illustrates how the colonial experiences of Native Californians differed from those of other tribal groups that confronted similar kinds of colonial programs involving Franciscan missionaries elsewhere in North America. The article stresses that the archaeology of colonialism is not simply an arcane academic exercise but, rather, has real-life relevancy for people who remain haunted by the legacies of colonialism, such as those petitioning for federal recognition in California.
De nouvelles perspectives pour la recherche en management international
Authors: Lemaire Jean-Paul , Mayrhofer Ulrike , Milliot Eric
Published: February 2013

Cet article porte sur les effets de l’accélération de l’intégration mondiale d’espaces économiques, multiples et enchevêtrés, dans le but de permettre aux différents acteurs impliqués d’en cerner les enjeux. Les auteurs identifient quatre axes de recherche, bien souvent interconnectés, dans le champ du Management et du Développement International des organisations : l’intégration de nouvelles logiques de diagnostic et de prise de décision, la prise en compte de nouveaux profils de parties prenantes, la montée en puissance de nouveaux rapports de force entre espaces et acteurs économiques, et les relations entre schémas organisationnels et évolutions interculturelles au sein des organisations.
Les effets de la notation financière sur les stratégies d’internationalisation des firmes multinationales européennes
Authors: Lantin François
Published: February 2013

Les sociétés sont contraintes dans leur stratégie d’internationalisation par leur niveau d’endettement révélé par leur notation financière. En s’appuyant sur 402 changements de note de 182 firmes multinationales européennes annoncés par Standard and Poor’s, les résultats valident l’asymétrie moyenne de réaction des marchés d’actions : diminution du cours boursier suite aux dégradations de note mais absence de réaction consécutive aux relèvements. Cependant, les variations individuelles des prix des actions ne seraient fortement négatives que dans la moitié des cas pour les baisses de note et nulles voire positives dans l’autre moitié. Des résultats symétriques sont obtenus pour les hausses de note.
L’impact des motivations des parents sur la performance des coentreprises internationales implantées en Turquie
Authors: Dikmen Gorini Laure
Published: February 2013

L’objectif de cet article est d’étudier, d’une part, les motivations des partenaires des coentreprises internationales entre les pays émergents et les pays développés et, d’autre part, l’impact de ces motivations sur la performance de l’entité commune. L’analyse de 123 coentreprises internationales en Turquie montre que les motivations des partenaires sont complémentaires. Les parents turcs souhaitent partager les frais de recherche et de développement, maîtriser une nouvelle technologie et obtenir de nouvelles ressources. Les partenaires étrangers sont davantage motivés par la diversification et l’expansion de leur firme, l’accès à de nouveaux marchés et la compatibilité des attentes avec leur partenaire local.
La constitution et la structuration des réseaux sociaux : un facteur clé de succès de l’expatriation
Authors: Mérignac Olivier , Grillat Marie-Laure
Published: February 2013

Cette recherche analyse la constitution et la structuration des réseaux sociaux des expatriés à travers une analyse longitudinale rétrospective. Cette approche a permis d’identifier les vecteurs professionnels, familiaux et environnementaux de la constitution du lien mais surtout de comprendre à quels moments ils interviennent dans la construction des différents réseaux. Nos résultats montrent que la sphère professionnelle et la sphère familiale ont des rôles différents dans le processus de structuration des réseaux. La famille joue un rôle primordial dans la création des liens forts nécessaires à l’adaptation du cadre et agit également comme activateur de liens plus hétérogènes au sein de réseaux sociaux ouverts.
Large-Scale Proteomics in Early Pregnancy and Hypertensive Disorders of Pregnancy
Authors: Greenland Philip , Segal Mark R. , McNeil Rebecca B. , Parker Corette B. , Pemberton Victoria L. , Grobman William A. , Silver Robert M. , Simhan Hyagriv N. , Saade George R. , Ganz Peter , Mehta Priya , Catov Janet M. , Bairey Merz C. Noel , Varagic Jasmina , Khan Sadiya S. , Parry Samuel , Reddy Uma M. , Mercer Brian M. , Wapner Ronald J. , Haas David M.
Published: July 2024

Importance

There is no consensus regarding the best method for prediction of hypertensive disorders of pregnancy (HDP), including gestational hypertension and preeclampsia.

Objective

To determine predictive ability in early pregnancy of large-scale proteomics for prediction of HDP.

Design, Setting, and Participants

This was a nested case-control study, conducted in 2022 to 2023, using clinical data and plasma samples collected between 2010 and 2013 during the first trimester, with follow-up until pregnancy outcome. This multicenter observational study took place at 8 academic medical centers in the US. Nulliparous individuals during first-trimester clinical visits were included. Participants with HDP were selected as cases; controls were selected from those who delivered at or after 37 weeks without any HDP, preterm birth, or small-for-gestational-age infant. Age, self-reported race and ethnicity, body mass index, diabetes, health insurance, and fetal sex were available covariates.

Exposures

Proteomics using an aptamer-based assay that included 6481 unique human proteins was performed on stored plasma. Covariates were used in predictive models.

Main Outcomes and Measures

Prediction models were developed using the elastic net, and analyses were performed on a randomly partitioned training dataset comprising 80% of study participants, with the remaining 20% used as an independent testing dataset. Primary measure of predictive performance was area under the receiver operating characteristic curve (AUC).

Results

This study included 753 HDP cases and 1097 controls with a mean (SD) age of 26.9 (5.5) years. Maternal race and ethnicity were 51 Asian (2.8%), 275 non-Hispanic Black (14.9%), 275 Hispanic (14.9%), 1161 non-Hispanic White (62.8% ), and 88 recorded as other (4.8%), which included those who did not identify according to these designations. The elastic net model, allowing for forced inclusion of prespecified covariates, was used to adjust protein-based models for clinical and demographic variables. Under this approach, no proteins were selected to augment the clinical and demographic covariates. The predictive performance of the resulting model was modest, with a training set AUC of 0.64 (95% CI, 0.61-0.67) and a test set AUC of 0.62 (95% CI, 0.56-0.68). Further adjustment for study site yielded only minimal changes in AUCs.

Conclusions and Relevance

In this case-control study with detailed clinical data and stored plasma samples available in the first trimester, an aptamer-based proteomics panel did not meaningfully add to predictive utility over and above clinical and demographic factors that are routinely available.
Early Prostate Cancer Deaths Among Men With Higher vs Lower Genetic Risk
Authors: Plym Anna , Zhang Yiwen , Stopsack Konrad H. , Ugalde-Morales Emilio , Seibert Tyler M. , Conti David V. , Haiman Christopher A. , Baras Aris , Stocks Tanja , Drake Isabel , Penney Kathryn L. , Giovannucci Edward , Kibel Adam S. , Wiklund Fredrik , Mucci Lorelei A. ,   Regeneron Genetics Center
Published: July 2024

Importance

Prostate cancer, a leading cause of cancer death among men, urgently requires new prevention strategies, which may involve targeting men with an underlying genetic susceptibility.

Objective

To explore differences in risk of early prostate cancer death among men with higher vs lower genetic risk to inform prevention efforts.

Design, Setting, and Participants

This cohort study used a combined analysis of genotyped men without prostate cancer at inclusion and with lifestyle data in 2 prospective cohort studies in Sweden and the US, the Malmö Diet and Cancer Study (MDCS) and the Health Professionals Follow-Up Study (HPFS), followed up from 1991 to 2019. Data were analyzed between April 2023 and April 2024.

Exposures

Men were categorized according to modifiable lifestyle behaviors and genetic risk. A polygenic risk score above the median or a family history of cancer defined men at higher genetic risk (67% of the study population); the remaining men were categorized as being at lower genetic risk.

Main Outcomes and Measures

Prostate cancer death analyzed using time-to-event analysis estimating hazard ratios (HR), absolute risks, and preventable deaths by age.

Results

Among the 19 607 men included for analysis, the median (IQR) age at inclusion was 59.0 (53.0-64.7) years (MDCS) and 65.1 (58.0-71.8) years (HPFS). During follow-up, 107 early (by age 75 years) and 337 late (after age 75 years) prostate cancer deaths were observed. Compared with men at lower genetic risk, men at higher genetic risk had increased rates of both early (HR, 3.26; 95% CI, 1.82-5.84) and late (HR, 2.26; 95% CI, 1.70-3.01) prostate cancer death, and higher lifetime risks of prostate cancer death (3.1% vs 1.3% [MDCS] and 2.3% vs 0.6% [HPFS]). Men at higher genetic risk accounted for 94 of 107 early prostate cancer deaths (88%), of which 36% (95% CI, 12%-60%) were estimated to be preventable through adherence to behaviors associated with a healthy lifestyle (not smoking, healthy weight, high physical activity, and a healthy diet).

Conclusions and Relevance

In this 20-year follow-up study, men with a genetic predisposition accounted for the vast majority of early prostate cancer deaths, of which one-third were estimated to be preventable. This suggests that men at increased genetic risk should be targeted in prostate cancer prevention strategies.
Understanding of Endomucin: a Multifaceted Glycoprotein Functionality in Vascular Inflammatory‐Related Diseases, Bone Diseases and Cancers
Authors: Li Xiaoqing , Lv Qing , Liu Peng , Han Guiping , Yu Shan
Published: July 2024

Endomucin (MUC14), encoded by EMCN gene, is an O‐glycosylated transmembrane mucin that is mainly found in venous endothelial cells (ECs) and highly expressed in type H vessels of bone tissue. Its main biological functions include promoting endothelial generation and migration through the vascular endothelial growth factor (VEGF) signaling pathway and inhibiting the adhesion of inflammatory cells to ECs. In addition, it induces angiogenesis and promotes bone formation. Due to the excellent functions of Endomucin in the above aspects, it provides a new research target for the treatment of vascular inflammatory‐related diseases and bone diseases. Based on the current understanding of its function, the research of Endomucin mainly focuses on the above two diseases. As it is known, the progression of cancer is closely related to angiogenesis. Endomucin recently is found to be differentially expressed in a variety of tumors and correlated with survival rate. The biological role of Endomucin in cancer is opaque. This article introduces the research progress of Endomucin in vascular inflammatory‐related diseases and bone diseases, discusses its application value and prospect in the treatment, and collects the latest research situation of Endomucin in tumors, to provide meaningful evidence for expanding the research field of Endomucin.