bluuebunny/crossref_metadata_2025 huggingface dataset:
Can a coupled meteorology–chemistry model reproduce the historical trend in aerosol direct radiative effects over the Northern Hemisphere?
Authors: Xing J. , Mathur R. , Pleim J. , Hogrefe C. , Gan C.-M. , Wong D. C. , Wei C.
Published: September 2015

Abstract. The ability of a coupled meteorology–chemistry model, i.e., Weather Research and Forecast and Community Multiscale Air Quality (WRF-CMAQ), to reproduce the historical trend in aerosol optical depth (AOD) and clear-sky shortwave radiation (SWR) over the Northern Hemisphere has been evaluated through a comparison of 21-year simulated results with observation-derived records from 1990 to 2010. Six satellite-retrieved AOD products including AVHRR, TOMS, SeaWiFS, MISR, MODIS-Terra and MODIS-Aqua as well as long-term historical records from 11 AERONET sites were used for the comparison of AOD trends. Clear-sky SWR products derived by CERES at both the top of atmosphere (TOA) and surface as well as surface SWR data derived from seven SURFRAD sites were used for the comparison of trends in SWR. The model successfully captured increasing AOD trends along with the corresponding increased TOA SWR (upwelling) and decreased surface SWR (downwelling) in both eastern China and the northern Pacific. The model also captured declining AOD trends along with the corresponding decreased TOA SWR (upwelling) and increased surface SWR (downwelling) in the eastern US, Europe and the northern Atlantic for the period of 2000–2010. However, the model underestimated the AOD over regions with substantial natural dust aerosol contributions, such as the Sahara Desert, Arabian Desert, central Atlantic and northern Indian Ocean. Estimates of the aerosol direct radiative effect (DRE) at TOA are comparable with those derived by measurements. Compared to global climate models (GCMs), the model exhibits better estimates of surface-aerosol direct radiative efficiency (Eτ). However, surface-DRE tends to be underestimated due to the underestimated AOD in land and dust regions. Further investigation of TOA-Eτ estimations as well as the dust module used for estimates of windblown-dust emissions is needed.
Oxygen isotope mass balance of atmospheric nitrate at Dome C, East Antarctica, during the OPALE campaign
Authors: Savarino J. , Vicars W. C. , Legrand M. , Preunkert S. , Jourdain B. , Frey M. M. , Kukui A. , Caillon N. , Gil Roca J.
Published: September 2015

Abstract. Variations in the stable oxygen isotope composition of atmospheric nitrate act as novel tools for studying oxidative processes taking place in the troposphere. They provide both qualitative and quantitative constraints on the pathways determining the fate of atmospheric nitrogen oxides (NO + NO2 = NOx). The unique and distinctive 17O-excess (Δ17O = δ17O − 0.52 × δ18O) of ozone, which is transferred to NOx via oxidation, is a particularly useful isotopic fingerprint in studies of NOx transformations. Constraining the propagation of 17O-excess within the NOx cycle is critical in polar areas where there exists the possibility of extending atmospheric investigations to the glacial/interglacial time scale using deep ice core records of nitrate. Here we present measurements of the comprehensive isotopic composition of atmospheric nitrate collected at Dome C (East Antarctic plateau) during the austral summer of 2011/12. Nitrate isotope analysis has been here combined for the first time with key precursors involved in nitrate production (NOx, O3, OH, HO2, RO2, etc.) and direct observations of the transferrable Δ17O of surface ozone, which was measured at Dome C throughout 2012 using our recently developed analytical approach. Assuming that nitrate is mainly produced in Antarctica in summer through the OH + NO2 pathway and using concurrent measurements of OH and NO2, we calculated a Δ17O signature for nitrate in the order of (21–22 ± 3) ‰. These values are lower than the measured values that ranged between 27 and 31 ‰. This discrepancy between expected and observed Δ17O(NO3−) values suggests the existence of an unknown process that contributes significantly to the atmospheric nitrate budget over this east Antarctic region.
Global and zonal tropospheric ozone variations from 2003–2011 as seen by SCIAMACHY
Authors: Ebojie F. , Burrows J. P. , Gebhardt C. , Ladstätter-Weißenmayer A. , von Savigny C. , Rozanov A. , Weber M. , Bovensmann H.
Published: September 2015

Abstract. An analysis of the tropospheric ozone (O3) columns (TOCs) derived from SCIAMACHY limb-nadir-matching (LNM) observations during 2003–2011, focusing on the zonal and global variations in TOC is described. The changes are derived using a multivariate linear regression model. TOC shows a change of −0.2 ± 0.4 % yr−1, 0.3 ± 0.4 % yr−1, 0.1 ± 0.5 % yr−1 and 0.1 ± 0.2 % yr−1, which are not statistically significant at the 2 σ level in the latitude bands 30–50° N, 20° S–0, 0–20° N and 50–30° S, respectively. Tropospheric O3 shows statistically significant increases over some regions of South Asia (1–3 % yr−1), the South American continent (up to 2 % yr−1), Alaska (up to 2 % yr−1) and around Congo in Africa (up to 2 % yr−1). Significant increase in TOC is derived from the continental outflows including those of Australia (up to 2 % yr−1), Eurasia (1–3 % yr−1) and the South America (up to 3 % yr−1). Significant decrease in TOC (up to −3 % yr−1) is observed over some regions of the continents of North America, Europe and South America. Over the Oceanic regions, significant decrease in TOC of about −2 % yr−1 is observed over the outflows of Europe and North America.
Drizzle formation in stratocumulus clouds: effects of turbulent mixing
Authors: Magaritz-Ronen L. , Pinsky M. , Khain A.
Published: September 2015

Abstract. The mechanism of drizzle formation in shallow stratocumulus clouds and the effect of turbulent mixing on this process are investigated. A Lagrangian-Eularian model of the cloud-topped boundary layer is used to simulate the cloud measured during flight RF07 of the DYCOMS-II field experiment. The model contains ~ 2000 air parcels that are advected in a turbulence-like velocity field. In the model all microphysical processes are described for each Lagrangian air volume, and turbulent mixing between the parcels is also taken into account. It was found that the first large drops form in air volumes that are closest to adiabatic and characterized by high humidity, extended residence near cloud top, and maximum values of liquid water content, allowing the formation of drops as a result of efficient collisions. The first large drops form near cloud top and initiate drizzle formation in the cloud. Drizzle is developed only when turbulent mixing of parcels is included in the model. Without mixing, the cloud structure is extremely inhomogeneous and the few large drops that do form in the cloud evaporate during their sedimentation. It was found that turbulent mixing can delay the process of drizzle initiation but is essential for the further development of drizzle in the cloud.
NOx lifetimes and emissions of hotspots in polluted background estimated by satellite observations
Authors: Liu F. , Beirle S. , Zhang Q. , Dörner S. , He K. B. , Wagner T.
Published: September 2015

Abstract. We present a new method to quantify NOx emissions and corresponding atmospheric lifetimes from OMI NO2 observations together with ECMWF wind fields without further model input for sources located in polluted background. NO2 patterns under calm wind conditions are used as proxy for the spatial patterns of NOx emissions, and the effective atmospheric NOx lifetime is determined from the change of spatial patterns measured at larger wind speeds. Emissions are subsequently derived from the NO2 mass above background integrated around the source of interest. Lifetimes and emissions are estimated for 17 power plants and 53 cities located in non-mountainous regions across China and the US. The derived lifetimes for non-mountainous sites are 3.8 ± 1.0 h on average with ranges of 1.8 to 7.5 h. The derived NOx emissions show generally good agreement with bottom-up inventories for power plants and cities. Global inventory significantly underestimated NOx emissions in Chinese cities, most likely due to uncertainties associated with downscaling approaches.
Solubility and reactivity of HNCO in water: insights into HNCO's fate in the atmosphere
Authors: Borduas N. , Place B. , Wentworth G. R. , Abbatt J. P. D. , Murphy J. G.
Published: September 2015

Abstract. A growing number of ambient measurements of isocyanic acid (HNCO) are being made, yet little is known about its fate in the atmosphere. To better understand HNCO's loss processes and particularly its atmospheric partitioning behavior, we measure its effective Henry's Law solubility coefficient KHeff with a bubbler experiment using chemical ionization mass spectrometry as the gas phase analytical technique. By conducting experiments at different pH values and temperature, a Henry's Law coefficient KH of 26 ± 2 M atm-1 is obtained, with an enthalpy of dissolution of −34 ± 2 kJ mol-1. Our approach also allows for the determination of HNCO's acid dissociation constant, which we determine to be Ka = 2.1 ± 0.2 × 10-4 M at 298 K. Furthermore, by using ion chromatography to analyze aqueous solution composition, we revisit the hydrolysis kinetics of HNCO at different pH and temperature conditions. Three pH dependent hydrolysis mechanisms are in play and we determine the Arrhenius expressions for each rate to be k1 = (4.4 ± 0.2) × 107 exp (−6000 ± 240/T) M s-1, k2 = (8.9±0.9) × 106 exp (−6770 ± 450/T) s-1 and k3 = (7.2±1.5) × 108 exp (−10 900 ± 1400/T) s-1 where k1 is for HNCO + H+ + H2O → NH4+ + CO2, k2 is for HNCO + H2 O → NH3 + CO2 and k3 is for NCO- + 2H2 O → NH3 + HCO3-. HNCO's lifetime against hydrolysis is therefore estimated to be 10 days to 28 years at pH values, liquid water contents, and temperatures relevant to tropospheric clouds, years in oceans and months in human blood. In all, a better parameterized Henry's Law coefficient and hydrolysis rates of HNCO allow for more accurate predictions of its concentration in the atmosphere and consequently help define exposure of this toxic molecule.
Isoprene chemistry in pristine and polluted Amazon environments: Eulerian and Lagrangian model frameworks and the strong bearing they have on our understanding of surface ozone and predictions of rainforest exposure to this priority pollutant
Authors: Levine J. G. , MacKenzie A. R. , Squire O. J. , Archibald A. T. , Griffiths P. T. , Abraham N. L. , Pyle J. A. , Oram D. E. , Forster G. , Brito J. F. , Lee J. D. , Hopkins J. R. , Lewis A. C. , Bauguitte S. J. B. , Demarco C. F. , Artaxo P. , Messina P. , Lathière J. , Hauglustaine D. A. , House E. , Hewitt C. N. , Nemitz E.
Published: September 2015

Abstract. This study explores our ability to simulate the atmospheric chemistry stemming from isoprene emissions in pristine and polluted regions of the Amazon basin. We confront two atmospheric chemistry models – a global, Eulerian chemistry-climate model (UM-UKCA) and a trajectory-based Lagrangian model (CiTTyCAT) – with recent airborne measurements of atmospheric composition above the Amazon made during the SAMBBA campaign of 2012. The simulations with the two models prove relatively insensitive to the chemical mechanism employed; we explore one based on the Mainz Isoprene Mechanism, and an updated one that includes changes to the chemistry of first generation isoprene nitrates (ISON) and the regeneration of hydroxyl radicals via the formation of hydroperoxy-aldehydes (HPALDS) from hydroperoxy radicals (ISO2). In the Lagrangian model, the impact of increasing the spatial resolution of trace gas emissions employed from 3.75° × 2.5° to 0.1° × 0.1° varies from one flight to another, and from one chemical species to another. What consistently proves highly influential on our simulations, however, is the model framework itself – how the treatment of transport, and consequently mixing, differs between the two models. The lack of explicit mixing in the Lagrangian model yields variability in atmospheric composition more reminiscent of that exhibited by the measurements. In contrast, the combination of explicit (and implicit) mixing in the Eulerian model removes much of this variability but yields better agreement with the measurements overall. We therefore explore a simple treatment of mixing in the Lagrangian model that, drawing on output from the Eulerian model, offers a compromise between the two models. We use this Lagrangian/Eulerian combination, in addition to the separate Eulerian and Lagrangian models, to simulate ozone at a site in the boundary layer downwind of Manaus, Brazil. The Lagrangian/Eulerian combination predicts a value for an AOT40-like accumulated exposure metric of around 1000 ppbv h, compared to just 20 ppbv h with the Eulerian model. The model framework therefore has considerable bearing on our understanding of the frequency at which, and the duration for which, the rainforest is exposed to damaging ground-level ozone concentrations.
Sensitivity analysis of polarimetric O2 A-band spectra for potential cloud retrievals using OCO-2/GOSAT measurements
Authors: Sanghavi S. , Lebsock M. , Stephens G.
Published: September 2015

Abstract. Clouds play a crucial role in Earth's radiative budget, yet their climate feedbacks are poorly understood. The advent of space-borne high resolution spectrometers probing the O2 A band, like GOSAT and OCO-2, could make it possible to simultaneously retrieve vertically resolved cloud parameters that play a vital role in Earth's radiative budget, thereby allowing a reduction of the corresponding uncertainty due to clouds. Such retrievals would also facilitate air mass bias reduction in corresponding measurements of CO2 columns. In this work, the hyperspectral, polarimetric response of the O2 A band to mainly three important cloud parameters, viz., optical thickness, top height and droplet size has been studied, revealing a different sensitivity to each for the varying atmospheric absorption strength within the A band. Cloud optical thickness finds greatest sensitivity in intensity measurements, the sensitivity of other Stokes parameters being limited to low cloud optical thicknesses. Cloud height had a negligible effect on intensity measurements at non-absorbing wavelengths but finds maximum sensitivity at an intermediate absorption strength, which increases with cloud height. The same is found to hold for cloud geometric thickness. The geometry-dependent sensitivity to droplet size is maximum at non-absorbing wavelengths and diminishes with increasing absorption strength. It has been shown that significantly more information on droplet size can be drawn from multi-angle measurements. We find that, in the absence of sunglint, the backscatter hemisphere (scattering angle larger than 90°) is richer in information on droplet size, especially in the glory and rainbow regions. It has been shown that I and Q generally have differing sensitivities to all cloud parameters. Thus, accurate measurements of two orthogonal components IP andIS (as in GOSAT) are expected to contain more information than measurements of only I, Ih or Iv (as in the case of OCO-2).
An airborne infrared laser spectrometer for in-situ trace gas measurements: application to tropical convection case studies
Authors: Catoire V. , Krysztofiak G. , Robert C. , Chartier M. , Jacquet P. , Guimbaud C. , Hamer P. D. , Marécal V.
Published: September 2015

Abstract. A three-channel laser absorption spectrometer called SPIRIT (SPectromètre InfraRouge In situ Toute altitude) has been developed for airborne measurements of trace gases in the troposphere and lower stratosphere. More than three different species can be measured simultaneously with high time resolution (each 1.6 s) using three individual CW-DFB-QCLs (Continuous Wave Distributed FeedBack Quantum Cascade Lasers) coupled to a single Robert multipass optical cell. The lasers are operated in a time-multiplexed mode. Absorption of the mid-infrared radiations occur in the cell (2.8 L with effective path lengths of 134 to 151 m) at reduced pressure, with detection achieved using a HgCdTe detector cooled by Stirling cycle. The performances of the instrument are described, in particular precisions of 1, 1 and 3 %, and volume mixing ratio (vmr) sensitivities of 0.4, 6 and 2.4 ppbv are determined at 1.6 s for CO, CH4 and N2O, respectively (at 1σ confidence level). Estimated accuracies without calibration are about 6 %. Dynamic measuring ranges of about four decades are established. The first deployment of SPIRIT was realized aboard the Falcon-20 research aircraft operated by DLR (Deutsches Zentrum für Luft- und Raumfahrt) within the frame of the SHIVA (Stratospheric Ozone: Halogen Impacts in a Varying Atmosphere) European project in November-December 2011 over Malaysia. The convective outflows from two large convective systems near Borneo Island (6.0° N–115.5° E and 5.5° N–118.5° E) were sampled above 11 km in altitude on 19 November and 9 December, respectively. Correlated enhancements in CO and CH4 vmr were detected when the aircraft crossed the outflow anvil of both systems. These enhancements were interpreted as the fingerprint of transport from the boundary layer up through the convective system and then horizontal advection in the outflow. Using these observations, the fraction of boundary layer air contained in fresh convective outflow was calculated to range between 22 and 31 %, showing the variability of the mixing taking place during convective transport.
Responses of two nonlinear microbial models to warming or increased carbon input
Authors: Wang Y. P. , Jiang J. , Chen-Charpentier B. , Agusto F. B. , Hastings A. , Hoffman F. , Rasmussen M. , Smith M. J. , Todd-Brown K. , Wang Y. , Xu X. , Luo Y. Q.
Published: September 2015

Abstract. A number of nonlinear microbial models of soil carbon decomposition have been developed. Some of them have been applied globally but have yet to be shown to realistically represent soil carbon dynamics in the field. Therefore a thorough analysis of their key differences will be very useful for the future development of these models. Here we compare two nonlinear microbial models of soil carbon decomposition: one is based on reverse Michaelis-Menten kinetics (model A) and the other on regular Michaelis-Menten kinetics (model B). Using a combination of analytic solutions and numerical simulations, we find that the oscillatory responses of carbon pools model A to a small perturbation in the initial pool sizes have a higher frequency and damps faster than model B. In response to soil warming, soil carbon always decreases in model A; but likely decreases in cool regions and increases in warm regions in model B. Maximum CO2 efflux from soil carbon decomposition (Fmax) after an increased carbon addition decreases with an increase in soil temperature in both models, and the sensitivity of Fmax to the amount of carbon input increases with soil temperature in model A; but decreases monotonically with an increase in soil temperature in model B. These differences in the responses to soil warming and carbon input between the two nonlinear models can be used to differentiate which model is more realistic with field or laboratory experiments. This will lead to a better understanding of the significance of soil microbial processes in the responses of soil carbon to future climate change at regional or global scales.
Automation of soil flux chamber measurements: potentials and pitfalls
Authors: Görres C.-M. , Kammann C. , Ceulemans R.
Published: September 2015

Abstract. Recent technological advances have enabled the wider application of automated chambers for soil greenhouse gas (GHG) flux measurements, several of them commercially available. However, only few studies addressed the difficulties and challenges associated with operating these systems. In this contribution we compared two commercial soil GHG chamber systems–the LI-8100A Automated Soil CO2 Flux System and the Greenhouse Gas Monitoring System AGPS. From April 2014 until August 2014, the two systems monitored in parallel soil respiration (SR) fluxes at a recently harvested poplar plantation, which provided a bare field situation directly after the harvest as well as a closed canopy later on. For the bare field situation (15 April–30 June 2014), the cumulated average SR obtained from the unfiltered datasets of the LI-8100A and the AGPS were 520 and 433 g CO2 m−2, respectively. For the closed canopy phase (01 July–31 August 2014), which was characterized by a higher soil moisture content, the cumulated average SR estimates were not significantly different with 507 and 501 g CO2 m−2 for the AGPS and the LI-8100A, respectively. Flux quality control and filtering did not significantly alter the results obtained by the LI-8100A, whereas the AGPS SR estimates were reduced by at least 20 %. The main reasons for the observed differences in the performance of the two systems were (i) a lower data coverage provided by the AGPS due to technical problems; (ii) incomplete headspace mixing in the AGPS chambers; (iii) lateral soil CO2 diffusion below the collars during AGPS chamber measurements; (iv) increased root growth within the LI-8100A collars; and (v) a possible overestimation of nighttime SR fluxes by the LI-8100A. In contrast to the LI-8100A, the AGPS had the gas sample inlets installed inside the collars and not the chambers. This unique design feature enabled for the first time the detection of disturbed chamber measurements during nights with a stratified atmosphere, resulting in unbiased nighttime SR estimates. Thus besides providing high temporal frequency flux data, automated chamber systems offer another possibility to greatly improve our understanding of SR fluxes.
Modelling above-ground carbon dynamics using multi-temporal airborne lidar: insights from a Mediterranean woodland
Authors: Simonson W. , Ruiz-Benito P. , Valladares F. , Coomes D.
Published: September 2015

Abstract. Woodlands represent highly significant carbon sinks globally, though could lose this function under future climatic change. Effective large-scale monitoring of these woodlands has a critical role to play in mitigating for, and adapting to, climate change. Mediterranean woodlands have low carbon densities, but represent important global carbon stocks due to their extensiveness and are particularly vulnerable because the region is predicted to become much hotter and drier over the coming century. Airborne lidar is already recognized as an excellent approach for high-fidelity carbon mapping, but few studies have used multi-temporal lidar surveys to measure carbon fluxes in forests and none have worked with Mediterranean woodlands. We use a multi-temporal (five year interval) airborne lidar dataset for a region of central Spain to estimate above-ground biomass (AGB) and carbon dynamics in typical mixed broadleaved/coniferous Mediterranean woodlands. Field calibration of the lidar data enabled the generation of grid-based maps of AGB for 2006 and 2011, and the resulting AGB change were estimated. There was a close agreement between the lidar-based AGB growth estimate (1.22 Mg ha−1 year−1) and those derived from two independent sources: the Spanish National Forest Inventory, and a~tree-ring based analysis (1.19 and 1.13 Mg ha−1 year−1, respectively). We parameterised a simple simulator of forest dynamics using the lidar carbon flux measurements, and used it to explore four scenarios of fire occurrence. Under undisturbed conditions (no fire occurrence) an accelerating accumulation of biomass and carbon is evident over the next 100 years with an average carbon sequestration rate of 1.95 Mg C ha−1 year−1. This rate reduces by almost a third when fire probability is increased to 0.01, as has been predicted under climate change. Our work shows the power of multi-temporal lidar surveying to map woodland carbon fluxes and provide parameters for carbon dynamics models. Space deployment of lidar instruments in the near future could open the way for rolling out wide-scale forest carbon stock monitoring to inform management and governance responses to future environmental change.
The eigenvalue problem for ice-shelf vibrations: comparison of a full 3-D model with the thin plate approximation
Authors: Konovalov Y. V.
Published: September 2015

Abstract. Ice-shelf forced vibration modelling is performed using a full 3-D finite-difference elastic model, which also takes into account sub-ice seawater flow. The ocean flow in the cavity is described by the wave equation; therefore, ice-shelf flexures result from hydrostatic pressure perturbations in sub-ice seawater layer. Numerical experiments have been carried out for idealized rectangular and trapezoidal ice-shelf geometries. The ice-plate vibrations are modelled for harmonic ingoing pressure perturbations and for high-frequency spectra of the ocean swells. The spectra show distinct resonance peaks, which demonstrate the ability to model a resonant-like motion in the suitable conditions of forcing. The spectra and ice-shelf deformations obtained by the developed full 3-D model are compared with the spectra and the deformations modelled by the thin-plate Holdsworth and Glynn model (1978). The main resonance peaks and ice-shelf deformations in the corresponding modes, derived by the full 3-D model, are in agreement with the peaks and deformations obtained by the Holdsworth and Glynn model. The relative deviation between the eigenvalues (periodicities) in the two compared models is about 10 %. In addition, the full model allows observation of 3-D effects, for instance, the vertical distribution of the stress components in the plate. In particular, the full model reveals an increase in shear stress, which is neglected in the thin-plate approximation, from the terminus towards the grounding zone with a maximum at the grounding line in the case of the considered high-frequency forcing. Thus, the high-frequency forcing can reinforce the tidal impact on the ice-shelf grounding zone causing an ice fracture therein.
Technical Note: Remote sensing of sea surface salinity using the propagation of low-frequency navigation signals
Authors: Astin I. , Feng Y.
Published: September 2015

Abstract. This paper introduces a potential method for the remote sensing of sea surface salinity (SSS) using the measured propagation delay of low-frequency Loran-C signals transmitted over an all-seawater path between the Sylt station in Germany and an integrated Loran-C/GPS receiver located in Harwich, UK. The overall delay variations in Loran-C surface waves along the path may be explained by changes in sea surface properties (especially the temperature and salinity), as well as atmospheric properties that determine the refractive index of the atmosphere. After removing the atmospheric and sea surface temperature (SST) effects from the measured delay, the residual delay revealed a temporal variation similar to that of SSS data obtained by the European Space Agency's Soil Moisture and Ocean Salinity (SMOS) satellite.
Influence of humic acid applications on soil physicochemical properties
Authors: Gümüş İ. , Şeker C.
Published: September 2015

Abstract. Soil structure is often said to be the key to soil productivity since a fertile soil, with desirable soil structure and adequate moisture supply, constitutes a productive soil. Soil structure influences soil water movement and retention, erosion, crusting, nutrient recycling, root penetration and crop yield. The objective of this work is to study, humic acid (HA) application on some physical and chemical properties in weak structured soils investigated. The approach involved establishing a plot experiment in the laboratory conditions. Different rates of HA (control, 0.5, 1, 2 and 4 %) were applied to soil at three incubation periods (21, 42 and 62 days). At the end of the each incubation period, the changes in physicochemical properties were measured. Generally, HA addition increased EC values at the all incubation periods. HA applications decreased soil modulus of rupture. Application of HA at the rate of 4 % was significantly increased soil organic carbon contents. HA applications at the rate of 4 % significantly increased both mean soil total nitrogen content and aggregate stability after at three incubation periods (p < 0.05). Therefore, HA was potential to improve structure of soil in short term.
Sediment loss and its cause in Puerto Rico watersheds
Authors: Yuan Y. , Jiang Y. , Taguas E. V. , Mbonimpa E. G. , Hu W.
Published: September 2015

Abstract. A major environmental concern in the Commonwealth of Puerto Rico is increased sediment load to water reservoirs, to estuaries, and finally to coral reef areas outside the estuaries. Sediment deposition has significantly reduced the storage capacity of reservoirs, and sediments, with their associated contaminants and nutrients that are adsorbed, can stress corals and negatively impact reef health. To prevent and manage sediment loss it is therefore important to understand local soil erosion and sediment transport processes. The main objective of this study was to determine the influence of landscape characteristics on sediment loss. We analyzed available precipitation and sediment data collected in Puerto Rico during the past three decades, as well as information on land use, soil properties, and topography. Our partial least squares analysis was not very successful in identifying major factors associated with sediment loss due to the complexity of the study's watersheds; however, it was found that topography and rainfall factors do not play a leading role. Sediment loss from the ridge watersheds in Puerto Rico was mainly caused by interactions of development, heavy rainfall events (especially hurricanes), and steep mountainous slopes associated with the ridges. These results improve our understanding of sediment loss resulting from changes in land use/cover within a Puerto Rico watershed, and allow stakeholders to make more informed decisions about land use planning.
La emigración de la población de la Checoslovaquia socialista en el lenguaje de la propaganda comunista
Authors: Štefančík Radoslav , Nemcová Alica
Published: September 2015

El presente artículo explica los métodos y formas de propaganda de los régimenes no democráticos tomando como ejemplo la propaganda comunista respecto a la emigración. El propósito del artículo es averiguar cómo veía la élite política comunista a la gente que abandonaba el país, contra qué tipos de emigrantes iba dirigida la propaganda comunista y qué medios de expresión se utilizaban en la prensa comunista para caracterizar a los exiliados políticos. Partimos de la hipótesis de que el lenguaje propagandístico de los comunistas en contra de los emigrantes no cambiaba en función de la rigidez del régimen comunista. De este modo, los emigrantes eran considerados enemigos del régimen tanto en el periodo totalitario de los años cincuenta como en el periodo autoritario de los ochenta. En el presente texto se realiza un análisis de los contenidos de los medios de comunicación escritos de ambas épocas. En la primera parte, la parte teórica, se presenta el papel que desempeña la propaganda en los regímenes no democráticos. A continuación, se explican los motivos de la emigración durante la época objeto de análisis y, finalmente, se analiza el lenguaje de la propaganda del partido comunista.
Los orígenes del control informativo en las coberturas de guerra
Authors: Lavín de las Heras Eva , Römer Pieretti Max
Published: September 2015

La cobertura de los conflictos, desde sus inicios, ha estado muy ligada a la relación que han mantenido los militares y los medios. Desde la libertad de la que gozaban en sus primeros conflictos, aunque no exentos de problemas, pasando por la censura estricta que sufrieron en la Primera Guerra Mundial hasta el encorsetamiento al que se han tenido que enfrentar en las últimas guerras. La guerra de Vietnam marcaría un punto de inflexión en estas relaciones, y tras la invasión de Granada los militares pondrían en marcha un nuevo escenario informativo, el llamado “pool” informativo o agrupación de corresponsales. La falta de una guía clara y la lucha de ambos por controlar su espacio, ha hecho que las relaciones entre medios y militares sean siempre complicadas, por lo que las normas han ido evolucionando a cada conflicto marcando el futuro de las coberturas de prensa y por ende, el periodismo de guerra.
Prensa, política y orden social en Buenos Aires durante la década de 1850
Authors: Wasserman Fabio
Published: September 2015

El trabajo examina algunas reflexiones y discusiones sobre el rol y la naturaleza de la prensa que se produjeron en Buenos Aires durante la década de 1850 y que hacían referencia a las dificultades que implicaba congeniar la libertad y el orden. Esto se debía a que la prensa era considerada como un pilar de las sociedades republicanas y civilizadas, pero también como un agente capaz de corroer el orden social y político.
Reality Shows in Chile, origen y derrotero. Diálogos Histórico-Comunicacionales
Authors: Pérez González Patricio Octavio
Published: September 2015

Los programas de televisión conocidos como Reality shows son un formato televisivo de nuestros tiempos, sin embargo, las prácticas de observación de la intimidad individual y/o grupal han sido desarrolladas desde hace miles de años, algunas veces impulsadas por el placer del voyerismo o por el encanto del morbo; otras tantas, con el fin de vigilar, dirigir y mantener el statu quo. Este trabajo ofrece una propuesta alternativa a la explicación de la aparición de este tipo de programas de TV y la sienta en las prácticas gubernamentales ligadas al terrorismo de Estado moderno inauguradas a fines del siglo XVIII y rememoradas por diferentes regímenes hasta nuestros días.
Upín y IPIN : promoviendo la cultura malasia a través de los valores de la animación
Authors: Abdul Ghani Dahlan Bin
Published: September 2015

Recientemente los niños en Malasia están siendo fuertemente expuestos cuando no influenciados por los medios masivos de entretenimiento digital. Esto les lleva una falta de comprensión y apreciación de la importancia de los valores de su propia cultura. La serie de animación propia Upin & Ipin ha promovido con éxito las diferentes culturas de Malasia y obtenido valores culturales significativos que representan a su arte, incluyendo el islámico, y proporcionando así una plataforma de relación armónica entre los diferentes grupos que componen la sociedad en Malasia, ya sea civil o religiosa. El foco de esta investigación analizará el uso de su cultura icónica como fondo, con elementos tales como su estilo de vida, los arquetipos de personajes y su narrativa (storytelling). De sus resultados se espera puedan beneficiarse a las generaciones más jóvenes de Malasia, al conocer el significado implícito y la importancia de la cultura de su país.
Un mundo en transición. Objetos para los cuidados en España entre 1855 y 1955
Authors: Arredondo-González Claudia Patricia , De la cuesta Benjumea Carmen , Ávila Olivares José Antonio
Published: September 2015

Objetivo: describir el mundo material para los cuidados de enfermería en España entre 1855 y 1955. Método: estudio histórico, con procedimientos de investigación cualitativa. Las fuentes de información fueron manuales dirigidos a la formación de profesionales dedicados al cuidado de los enfermos. Resultados: en los manuales revisados, el contexto, los escenarios y las personas dedicadas a los cuidados se presentan concurrentemente. La habitación con su mobiliario y condiciones físicas y ambientales era el escenario principal para cuidar. Esta, junto a los objetos utilizados en ella con finalidad terapéutica, conformaba el mundo material para los cuidados. Los objetos del mundo material tenían cuatro propiedades respecto al uso: 1) reutilizables, si se usaban más de una vez; 2) polivalentes, cuando tenían diferentes usos prácticos; 3) sustituibles, otros podían reemplazarlos en el uso, y 4) importados, se incorporaban objetos de otros contextos al escenario de los cuidados. Discusión y conclusiones: el mundo material para los cuidados en España en la época de interés se encontraba en un contexto de salud-enfermedad de transición: de la teoría de los miasmas a la de los gérmenes, de proporcionar cuidados generalistas a cuidados especializados y de la presencia de diferentes figuras profesionales dedicadas al cuidado a su unificación. Este era un contexto amplio, tecnológico y heterogéneo. Las propiedades de los objetos enriquecían este mundo material y facilitaban la compleja y creativa labor de quienes cuidaban, cuyas herramientas de trabajo se describían en los manuales como sencillas y vulgares.
Missed Nursing Care in Hospitalized Patients
Authors: Moreno-Monsiváis María Guadalupe , Moreno-Rodríguez Catalina , Interial-Guzmán María Guadalupe
Published: September 2015

Objective: Determine missed nursing care in hospitalized patients and the factors related to missed care, according to the perception of the nursing staff and the patient. Method: Correlational descriptive study of a sample of 160 nurses and hospitalized patients, using the MISSCARE Nursing Survey. Results: Nursing personnel indicated there were fewer care omissions in continuous evaluation interventions (M=94.56; SD=11.10). The greatest number of omissions pertained to basic care interventions (M=80.2; SD=19.40). Patients mentioned there were fewer omissions in continuous evaluation interventions (M=96.32; SD=7.96), while the greatest number of omissions pertained to patient discharge and education (M=45.00; SD=23.22). The factors that contributed to missed nursing care, according to the nursing staff, were related to human resources (M=80.67; SD=17.06) and material resources (M=69.72; SD=23.45); patients mentioned human resources and communication. Conclusions: Nursing care that is not carried out according to the needs of the patient, or is omitted or delayed, was identified. This aspect is relevant, since nursing care is fundamental to the recovery of hospitalized patients.
How Nurses are Using the International Classifi cation of Functioning, Disability and Health: An Integrative Review
Authors: Rggia Piexak Diéssica , Cezar-Vaz Marta Regina , Alves Bonow Clarice , Sidney Costa Santos Silvana
Published: September 2015

Aim: The purpose of this study is to report the results of an integrative review of use of the International Classification of Functioning, Disability and Health (ICF) by nurses. This review is justified by the need for further investigation into use of the ICF in nursing, by nurses, so as to contribute to dialogue for the development of global, interdisciplinary and classification system comprehension. Methods: This integrative review included studies from 2001 to May 2015 in peer-reviewed journals. Two reviewers independently screened titles and abstracts for inclusion and completed data extraction. The papers were sourced from a number of electronic databases: MEDLINE/NML/PubMed, Web of Science, LILACS, CINAHL and SCIELO. Results: Twenty-six articles were included. Three themes on use of the ICF were identified: clinical nursing practice; teaching nursing students and nurses; and nursing research. Conclusion: This review helps nurses to visualise how and in what care environments the ICF is being used. It demonstrates the ICF has been used specifically in the rehabilitation nursing field, but offers some evidence of its use in occupational health as well.
Entrevista Percepción de Carga del Cuidado de Zarit: pruebas psicométricas para Colombia
Authors: Barreto-Osorio Ruth Vivian , Campos María Stella , Carrillo-González Gloria Mabel , Coral-Ibarra Rosa , Chaparro-Díaz Lorena , Duran Parra Myriam , Rosales-Jiménez Rosario , Tamara-Ortiz Vilma
Published: September 2015

Objetivo: determinar la validez y confiabilidad de la Entrevista de Percepción de Carga del Cuidado de Zarit, versión de 22 ítems en español, con cuidadores familiares de personas con enfermedades crónicas en Colombia. Materiales y métodos: estudio metodológico de corte transversal, con 652 cuidadores familiares de personas con enfermedades crónicas, residentes en las cinco regiones de Colombia, con el fin de establecer la validez de constructo, con un análisis factorial y la confiabilidad a través de la consistencia interna determinando el alfa de Cronbach. Resultado: respecto a la validez de constructo, el estudio reporta a partir de la asociación libre de la rotación Varimax la carga total, y en sus dimensiones que incluyen carga interpersonal, impacto del cuidado, y las competencias y expectativas sobre el cuidado. Las cargas factoriales corresponden a los ítems planteados para medir cada una de las dimensiones propuestas. Conclusión: el instrumento Entrevista de Percepción de Carga del Cuidado de Zarit, versión de 22 ítems en español, es una herramienta de fácil aplicación y comprensión en población colombiana de diferente nivel educativo, socioeconómico y cultural; además, mostró ser válido y confiable para evaluar la carga del cuidado en cuidadores familiares de personas con enfermedad crónica.
Validez y confiabilidad del instrumento “Percepción de comportamientos de cuidado humanizado de enfermería PCHE 3ª versión”
Authors: González-Hernández Oscar Javier
Published: September 2015

Objetivo: determinar la validez y confiabilidad del instrumento “Percepción de comportamientos de cuidado humanizado de enfermería (PCHE) 3ª versión”. Método: estudio descriptivo de tipo metodológico que hizo pruebas psicométricas al instrumento PCHE, que evalúa las características de la atención de enfermería en escenarios hospitalarios. El instrumento se revisó con la participación de 320 pacientes hospitalizados, y se realizaron mediciones de validez y confiabilidad mediante la valoración de la consistencia interna. Resultados: se obtuvo un índice de acuerdo de 0,92 y un índice de validez de contenido de 0,98 por el grupo de expertos. En el análisis factorial, se obtuvo una prueba de KMO de 0,956 y una prueba de esfericidad de Bartlett de 0,0; estos indicadores permitieron calcular las cargas factoriales y así determinar estadísticamente el constructo del instrumento que llevó a definir teóricamente tres dimensiones: cualidades del hacer de enfermería, apertura a la comunicación enfermera(o)-paciente y disposición para la atención. Conclusiones: el instrumento “Percepción de comportamientos de cuidado humanizado de enfermería 3ª versión” es válido y confiable para su aplicación en ámbitos hospitalarios.
Processo de trabalho em reabilitação: a perspectiva do trabalhador e do usuário
Authors: Dornelles Schoeller Soraia , Bento Luana , Lorenzetti Jorge , Pires Denise , Klein Ana Carolina
Published: September 2015

A prevalência das deficiências físicas constitui-se grave problema de saúde nas sociedades contemporâneas, o que demanda um processo longo de cuidados com ênfase na reabilitação. Este é um estudo de caso com abordagem qualitativa realizado em um centro de reabilitação de referência estadual, o qual envolveu 10 usuários e 22 trabalhadores com o objetivo de analisar o processo de trabalho em reabilitação. Foram coletados dados por meio de entrevistas com usuários e trabalhadores, observação sistemática e análise documental de prontuários. Emergiram quatro categorias temáticas: usuários com lesão medular atendidos no centro de reabilitação; equipe profissional que atua junto às pessoas com lesão medular; aspectos do processo de trabalho que favorecem a reabilitação; aspectos do processo de trabalho que a dificultam. Neste, destacaram-se déficits nos instrumentos de trabalho; nos aspectos que facilitam a reabilitação, destacou-se o trabalho em equipe humanizado. Conclui-se que o trabalho multiprofissional facilita o processo de reabilitação, o que traz benefícios aos usuários, e que o trabalho de enfermagem é parte essencial desse processo.
Calidad del cuidado de enfermería percibida por pacientes hospitalizados
Authors: Lenis-Victoria Claudia Andrea , Manrique-Abril Fred Gustavo
Published: September 2015

Objetivo: determinar la calidad del cuidado de enfermería percibida por pacientes hospitalizados en una clínica privada de Barranquilla, Colombia. Materiales y métodos: estudio descriptivo, transversal, cuantitativo. El tamaño muestral fue de 147 pacientes que tenían orden de egreso. Se utilizó el Cuestionario de Calidad del Cuidado de Enfermería (CUCACE), versión en castellano, previo cumplimiento de criterios de inclusión. Se tuvieron en cuenta aspectos éticos y normativos, guardando el rigor científico y metodológico. Los datos fueron organizados en Excel y procesados en SPSS. Resultados: la satisfacción y las experiencias de los pacientes con el cuidado de enfermería están por encima del 70 %, lo que indica resultados altamente positivos según la escala del CUCACE. Los resultados de asociación solo mostraron relación entre dichas variables y el sexo, mas no se encontró asociación significativa con el resto de las variables sociodemográficas. El 58,5 % fueron mujeres y el 41,5 %, hombres. El 96,6 % de los pacientes con que el cuidado de enfermería no requiere mejoría. Discusión y conclusión: los pacientes tienen una percepción positiva sobre el cuidado de enfermería recibido en la institución, con una puntuación de 93,22 para la dimensión de experiencia con el cuidado y de 78,12 en la dimensión de satisfacción, lo cual indica que la calidad del cuidado de enfermería percibida por los pacientes en la institución es buena. Los resultados son coherentes con lo hallado en estudios similares a nivel nacional e internacional.
Clusters as a factor of competitiveness of rural tourism destinations in the Danube region of the Republic of Serbia
Authors: Pejanović Radovan , Demirović Dunja , Glavaš-Trbić Danica , Maksimović Goran , Tomaš-Simin Mirela
Published: September 2015

The aim of this article is to identify the active tourism clusters in the Republic of Serbia, their structure, the degree of activity of cluster members, and the area of their operation. Therefore, based on a survey of the attitudes of tourism cluster members in the Danube region, their contribution in increasing the competitiveness of the rural tourism destinations was analyzed. Porter’s competitiveness model (“diamond model”) was used to determine the advantages and disadvantages of the rural areas of the Danube region as potential tourism destinations.
El número cien de la revista Encuentro
Authors: Bellanger Rodríguez Wendy
Published: September 2015

Con regocijo presentamos nuestra edición número cien. Celebramos la ocasión con entusiasmo pues nos confirma dos afortunadas realidades: la primera, que a través de los años nuestros colaboradores han mantenido su apoyo decidido a la revista; la segunda, que la UCA ha seguido apostando por el proyecto mientras otras universidades dejaron de financiar, o nunca financiaron ni financiarían una revista científica que no genera ingresos monetarios ni mercadeo para la institución. Por esas razones, celebramos el número cien con agradecimiento hacia nuestros colaboradores y hacia la Dirección Superior de la Universidad Centroamericana, que nos han brindado su apoyo, ánimo y respeto por muchos años.
Panamá, ¿qué comemos?: reflexiones sobre soberanía alimentaria y cultura
Authors: Sarsaneda del Cid Jorge
Published: September 2015

Se trata de hacer un repaso de la situación de desnutrición de los pueblos indígenas en Panamá y su increíble contraste con la riqueza de nutrición que tienen en sus alimentos tradicionales. Se buscan las causas de esta situación y se plantea el debate entre seguridad y soberanía alimentaria como marco para la búsqueda de las posibles soluciones. Se parte del conocimiento de los indígenas de la zona ngäbe (oeste de Panamá) principalmente y se mencionan muchas de las capacidades nutricionales de sus alimentos, algunos incluso milenarios.