bluuebunny/crossref_metadata_2025 huggingface dataset:
Analysing Simulation Results Statistically
Authors: Troitzsch Klaus G.
Published: May 2014

Many papers on simulation in the social sciences come up with significance tests in which the authors describe the effect of a parameter on some simulation outcome as significant on some level of significance. This chapter discusses the question whether significance tests on simulation results are meaningful, and it argues that it is the effect size much more than the existence of the effect that matters and that it is the description of the distribution function of the stochastic process incorporated in the simulation model which is important, particularly when this distribution is far from normal — which is particularly often the case when the simulation model is nonlinear.
A Unified Framework for Traditional and Agent-Based Social Network Modeling
Authors: Franchi Enrico , Tomaiuolo Michele
Published: May 2014

In the last sixty years of research, several models have been proposed to explain (i) the formation and (ii) the evolution of networks. However, because of the specialization required for the problems, most of the agent-based models are not general. On the other hand, many of the traditional network models focus on elementary interactions that are often part of several different processes. This phenomenon is especially evident in the field of models for social networks. Therefore, this chapter presents a unified conceptual framework to express both novel agent-based and traditional social network models. This conceptual framework is essentially a meta-model that acts as a template for other models. To support this meta-model, the chapter proposes a different kind of agent-based modeling tool that we specifically created for developing social network models. The tool the authors propose does not aim at being a general-purpose agent-based modeling tool, thus remaining a relatively simple software system, while it is extensible where it really matters. Eventually, the authors apply this toolkit to a novel problem coming from the domain of P2P social networking platforms.
Agents' Risk Relations in a Strategic Tax Reporting
Authors: Magessi Nuno Trindade , Antunes Luis
Published: May 2014

Tax evasion is a classic problem in the field of economics and has been intensively studied over the last few decades. So far, research has been focused, and reasonably followed, on extensions from the original model developed by Alligham and Sandmo (1972). This chapter has taken the initiative to analyse and discuss the behaviour of taxpayers and the relation with risk when they act strategically. In this sense, the authors propose to replicate and discuss the three main conceptual functions of the brain (expressed by Spinoza) when agents do their strategic options concerning tax evasion risk. Output results demonstrate a tendency for strategic taxpayers to first react in detriment of structured and complex reasoning. The assumption, commonly used in tax evasion literature, that taxpayers are exclusively rational, is liable of being refuted. Even the strategic taxpayers are reluctant to follow only their reason.
Rove beetles (Coleoptera: Staphylinidae) in Ontario, Canada soybean agroecosystems: assemblage diversity, composition, seasonality, and habitat use
Authors: Brunke A.J. , Bahlai C.A. , Klimaszewski J. , Hallett R.H.
Published: May 2014

Rove beetles (Coleoptera: Staphylinidae) are recognised as important components of agroecosystems and are best known for their contribution to biological control as predators of arthropod pests. Unfortunately, knowledge of their bionomics in North American agroecosystems is sparse. Therefore, soybean-hedgerow agroecosystems in Ontario, Canada, were surveyed in 2009–2010 to identify common, widespread members of the assemblage and characterise their seasonal activity patterns. The potential for refuge habitat in adjacent hedgerows was assessed outside of the growing season. The rove beetle assemblage of soybeans during the growing season was found to be a less diverse subset of that found in surrounding hedgerow areas, especially with respect to native species. Both native and non-native species were common (>1% activity density). Based on literature records, most common species were predaceous, univoltine, and adult overwintering. Most common species exhibited the highest activity density midway through the growing season and all were detected in hedgerow habitats outside the growing season. Comparisons with the staphylinid fauna of other North American agroecosystems revealed several common species to dominate assemblages under a wide variety of conditions. This research provides a framework for future agroecological studies of this poorly understood, but abundant and diverse, assemblage of beetles.
Simian Virus 40 Large T Antigen Induces IFN-Stimulated Genes through ATR Kinase
Authors: Forero Adriana , Giacobbi Nicholas S. , McCormick Kevin D. , Gjoerup Ole V. , Bakkenist Christopher J. , Pipas James M. , Sarkar Saumendra N.
Published: May 2014

Polyomaviruses encode a large T Ag (LT), a multifunctional protein essential for the regulation of both viral and host cell gene expression and productive viral infection. Previously, we have shown that stable expression of LT protein results in upregulation of genes involved in the IFN induction and signaling pathway. In this study, we focus on the cellular signaling mechanism that leads to the induction of IFN responses by LT. Our results show that ectopic expression of SV40 LT results in the induction of IFN-stimulated genes (ISGs) in human fibroblasts and confers an antiviral state. We describe a LT-initiated DNA damage response (DDR) that activates IFN regulatory factor 1, causing IFN-β production and consequent ISG expression in human cells. This IFN-β and ISG induction is dependent on ataxia-telangiectasia mutated and Rad3-related (ATR) kinase, but independent of ATM. ATR kinase inhibition using a selective kinase inhibitor (ETP-46464) caused a decrease in IFN regulatory factor 1 stabilization and ISG expression. Furthermore, expression of a mutant LT that does not induce DDR also does not induce IFN-β and ISGs. These results show that, in the absence of viral infection, LT-initiated activation of ATR-dependent DDR is sufficient for the induction of an IFN-β–mediated innate immune response in human cells. Thus, we have uncovered a novel and critical role for ATR as a mediator of antiviral responses utilizing LT.
Job embeddedness, work engagement and turnover intention of staff in a higher education institution: An exploratory study
Authors: Takawira Ndayiziveyi , Coetzee Melinde , Schreuder Dries
Published: May 2014

Orientation: The world economy is becoming increasingly knowledge driven, and intellectual capital is now considered as a human resource that affords organisations a competitive advantage. A high turnover rate in higher education and the importance of retaining staff are concerns that have resulted in increased interest in psychological variables, such as job embeddedness and work engagement that may influence employee retention.Research purpose: The objective of this study was to explore the relationship between job embeddedness, work engagement and turnover intention of staff in a higher education institution.Motivation for the study: Research on how employees’ job embeddedness and work engagement influence their turnover intention is important in the light of organisational concerns about retaining knowledgeable staff in the current higher education environment.Research design, approach and method: A cross-sectional quantitative survey was conducted on a non-probability purposive sample (N = 153) of academic and non-academic staff in a South African higher education institution.Main findings: Correlational analyses revealed significant relationships between job embeddedness, work engagement and turnover intention. Multiple regression analyses showed that organisational links and dedication significantly and negatively predict turnover intention.Practical/managerial implications: When designing retention strategies, management and human resource practitioners need to recognise how job embeddedness and work engagement influence the turnover intention of higher education staff.Contribution: These findings contribute valuable new knowledge that can be applied in the retention of staff in the higher education environment.
Deterministic control of randomly-terminated processes
Authors: Andrews June , Vladimirsky Alexander
Published: May 2014

We consider both discrete and continuous “uncertain horizon” deterministic control processes, for which the termination time is a random variable. We examine the dynamic programming equations for the value function of such processes, explore their connections to infinite-horizon and optimal-stopping problems, and derive sufficient conditions for the applicability of non-iterative (label-setting) methods. In the continuous case, the resulting PDE has a free boundary, on which all characteristic curves originate. The causal properties of “uncertain horizon” problems can be exploited to design efficient numerical algorithms: we derive causal semi-Lagrangian and Eulerian discretizations for the isotropic randomly-terminated problems, and use them to build a modified version of the Fast Marching Method. We illustrate our approach using numerical examples from optimal idle-time processing and expected response-time minimization.
Hemoglobin Concentration and Parasitemia on Hospital Admission Predict Risk of Multiple Organ Dysfunction Syndrome among Adults with Malaria
Authors: Walton Emily , Oliveros Henry , Villamor Eduardo
Published: May 2014

Risk factors for progression from acute malaria to multiple organ dysfunction syndrome (MODS) are poorly understood. The MODS is commonly diagnosed with the sequential organ failure assessment (SOFA) scale, but this scale has been understudied in patients with severe malaria. We conducted a cohort study among 426 adult males admitted to hospital with malaria in Bogotá, Colombia. We estimated SOFA scores and relative risks (RRs) for MODS during hospitalization according to patients' characteristics on admission. Risk of MODS was 7.3% over a median 6.0 days in hospital. Baseline hemoglobin was strongly, inversely associated with MODS (adjusted RR for hemoglobin ≤ 8.5 g/dL versus hemoglobin > 11 g/dL = 9.5, 95% confidence interval [CI]: 3.6, 25.3). Plasmodium falciparum malaria and parasitemia were positively associated with MODS. There was a strong interaction between baseline parasitemia and hemoglobin on MODS risk. In conclusion, the use of parasitemia and hemoglobin on admission to identify high-risk patients deserves consideration.
Prevalence of Bartonella quintana in Patients with Fever and Head Lice from Rural Areas of Sine-Saloum, Senegal
Authors: Diatta Georges , Mediannikov Oleg , Sokhna Cheikh , Bassene Hubert , Socolovschi Cristina , Ratmanov Pavel , Fenollar Florence , Raoult Didier
Published: May 2014

Trench fever is poorly known by the staff of health facilities that manage febrile patients in Senegal. Bartonella quintana DNA was identified in 5 of 274 (2%) febrile patients from two rural dispensaries and 2 of 71 (3%) head lice specimens collected from the same villages.
EFECTO DE LA SEVERIDAD DEL FUEGO EN LAS CARACTERÍSTICAS DE LA ESTRUCTURA FORESTAL EN RODALES DE CONÍFERAS
Authors: Ávila-Flores Diana Y. , González-Tagle Marco A. , Jiménez-Pérez Javier , Aguirre-Calderón Oscar A. , Treviño-Garza Eduardo , Vargas-Larreta Benedicto , Alanís Rodríguez Eduardo
Published: May 2014

El objetivo del presente trabajo fue realizar un análisis exploratorio de la distribución espacial del arbolado en rodales mixtos de coníferas de la Sierra Madre Oriental, afectados por un incendio en el verano de 1998, con el fin de conocer el grado en que la severidad de un incendio modifica las características estructurales de los mismos. El área seleccionada comprendió tres rodales mixtos de coníferas con tres grados de severidad de incendio (bajo, medio y alto). Los patrones de distribución espacial del arbolado se analizaron a través de la función K de Ripley. Asimismo, se analizó la interacción espacial de los árboles en relación con sus dimensiones y especies mediante una función de correlación de marca kmm(r). Se observó que conforme la severidad del incendio aumenta, la distribución espacial del arbolado tiende a la agregación y a la formación de rodales dimensionalmente heterogéneos, mientras que la composición de especies no fue afectada. El fuego influyó en estos bosques como un promotor de la diversidad dimensional, a pesar de que la mezcla espacial de especies tuvo una tendencia a la homogeneidad.
DISTRIBUCIÓN DE Heliopsis longipes (Heliantheae: Asteraceae), UN RECURSO ENDÉMICO DEL CENTRO DE MÉXICO
Authors: Cilia-López V. Gabriela , Aguirre-Rivera J. Rogelio , Espinosa-Reyes Guillermo , Flores-Cano Jorge A. , Reyes-Agüero J. Antonio , Juárez-Flores Bertha I.
Published: May 2014

Heliopsis longipes is a perennial herb endemic to Sierra de Álvarez and Sierra Gorda in central México. It is a species of major economic importance within its genus, due to the traditional uses of its root. Chemical and pharmacological studies have been performed with H. longipes roots, however recent studies regarding its distribution are lacking. The objective of the current study was to establish and document the geographic distribution and existing ecologic conditions of H. longipes. A review of published works regarding this species, as well as an examination of herbarium specimens has been conducted. Explorations in Sierra de Álvarez and Sierra Gorda were also conducted to locate populations of H. longipes. In each site, the physical and biological factors associated with the population were recorded. Heliopsis. longipes is distributed in the states of San Luis Potosí, Guanajuato and Querétaro, in steep canyons with oak and oak-pine forests and substrates of igneous origin, in Sierra de Álvarez and Sierra Gorda.
CRECIMIENTO Y PRODUCCIÓN DE Trema micrantha (L.) Blume, ÁRBOL PARA PAPEL AMATE
Authors: Cruz-Márquez Udavi , Negreros-Castillo Patricia , López-Binnqüist Citlalli , Mize Carl W.
Published: May 2014

En la comunidad de San Pablito en la Sierra Norte de Puebla, el árbol Trema micrantha (jonote) proporciona 80 % de la corteza utilizada en la manufactura del papel amate, una de las artesanías más importantes y conocidas de México. La comunidad se dedica en su totalidad a la producción del amate; sin embargo, el abastecimiento de corteza es irregular, insuficiente y proviene de lugares lejanos al centro productor. El presente estudio tiene tres objetivos: evaluar el interés de las personas de las comunidades vecinas para aumentar la producción de árboles de jonote, documentar las prácticas silvícolas y evaluar la tasa de crecimiento en altura y diámetro del árbol. Se entrevistaron 28 personas; 40 % están interesadas en aumentar la producción de jonote; 20 % aplica prácticas silvícolas como podas, eliminación de sombra, trasplante de jonote y adición de materia orgánica. Con base en la medición de 396 árboles de edad conocida, el jonote puede medir 7 cm de diámetro promedio en el primer año y 16 cm a los 5 años. Los mejores crecimientos se observaron en terrenos con pendientes menores de 70 %, altitudes entre 1,200 y 1,600 m, suelos fértiles y luz directa.
The relative dispersion of cloud droplets: its robustness with respect to key cloud properties
Authors: Tas E. , Teller A. , Altaratz O. , Axisa D. , Bruintjes R. , Levin Z. , Koren I.
Published: May 2014

Abstract. The relative dispersion (ε) of cloud droplet size distribution, defined as the ratio between cloud droplet size distribution width (σ) and cloud droplet average radius (⟨r⟩), is investigated using airborne measurements of warm cumulus clouds. The data is used to study the relation of ε with microphysical and thermodynamic characteristics of the clouds. The results show that ε is constrained with average values in the range of ~0.25–0.35. It is shown that ε is not correlated with the cloud droplet concentration or with the Liquid Water Content (LWC). However, the relative dispersion variance (related to the third moment of the droplets distribution) shows sensitivity to the droplets' concentration and LWC, suggesting smaller ε variability in more adiabatic regions in the clouds. A clear criterion for the usage of the in situ airborne measurements data for statistical moments' calculations is suggested.
An improved algorithm for polar cloud-base detection by ceilometer over the ice sheets
Authors: Van Tricht K. , Gorodetskaya I. V. , Lhermitte S. , Turner D. D. , Schween J. H. , Van Lipzig N. P. M.
Published: May 2014

Abstract. Optically thin ice and mixed-phase clouds play an important role in polar regions due to their effect on cloud radiative impact and precipitation. Cloud-base heights can be detected by ceilometers, low-power backscatter lidars that run continuously and therefore have the potential to provide basic cloud statistics including cloud frequency, base height and vertical structure. The standard cloud-base detection algorithms of ceilometers are designed to detect optically thick liquid-containing clouds, while the detection of thin ice clouds requires an alternative approach. This paper presents the polar threshold (PT) algorithm that was developed to be sensitive to optically thin hydrometeor layers (minimum optical depth τ ≥ 0.01). The PT algorithm detects the first hydrometeor layer in a vertical attenuated backscatter profile exceeding a predefined threshold in combination with noise reduction and averaging procedures. The optimal backscatter threshold of 3 × 10−4 km−1 sr−1 for cloud-base detection near the surface was derived based on a sensitivity analysis using data from Princess Elisabeth, Antarctica and Summit, Greenland. At higher altitudes where the average noise level is higher than the backscatter threshold, the PT algorithm becomes signal-to-noise ratio driven. The algorithm defines cloudy conditions as any atmospheric profile containing a hydrometeor layer at least 90 m thick. A comparison with relative humidity measurements from radiosondes at Summit illustrates the algorithm's ability to significantly discriminate between clear-sky and cloudy conditions. Analysis of the cloud statistics derived from the PT algorithm indicates a year-round monthly mean cloud cover fraction of 72% (±10%) at Summit without a seasonal cycle. The occurrence of optically thick layers, indicating the presence of supercooled liquid water droplets, shows a seasonal cycle at Summit with a monthly mean summer peak of 40 % (±4%). The monthly mean cloud occurrence frequency in summer at Princess Elisabeth is 46% (±5%), which reduces to 12% (±2.5%) for supercooled liquid cloud layers. Our analyses furthermore illustrate the importance of optically thin hydrometeor layers located near the surface for both sites, with 87% of all detections below 500 m for Summit and 80% below 2 km for Princess Elisabeth. These results have implications for using satellite-based remotely sensed cloud observations, like CloudSat that may be insensitive for hydrometeors near the surface. The decrease of sensitivity with height, which is an inherent limitation of the ceilometer, does not have a significant impact on our results. This study highlights the potential of the PT algorithm to extract information in polar regions from various hydrometeor layers using measurements by the robust and relatively low-cost ceilometer instrument.
New algorithm for integration between wireless microwave sensor network and radar for improved rainfall measurement and mapping
Authors: Liberman Y. , Samuels R. , Alpert P. , Messer H.
Published: May 2014

Abstract. One of the main challenges for meteorological and hydrological modelling is accurate rainfall measurement and mapping across time and space. To date the most effective methods for large scale rainfall estimates are radar, satellites, and more recently, received signal level (RSL) measurements received from commercial microwave networks (CMN). While these methods provide improved spatial resolution over traditional rain gauges, these have their limitations as well. For example, the wireless CMN, which are comprised of microwave links (ML), are dependant upon existing infrastructure, and the ML arbitrary distribution in space. Radar, on the other hand, is known in its limitation in accurately estimating rainfall in urban regions, clutter areas and distant locations. In this paper the pros and cons of the radar and ML methods are considered in order to develop a new algorithm for improving rain fall measurement and mapping, which is based on data fusion of the different sources. The integration is based on an optimal weighted average of the two data sets, taking into account location, number of links, rainfall intensity and time step. Our results indicate that by using the proposed new method we not only generate a more accurate 2-D rainfall reconstructions, compared with actual rain intensities in space, but also the reconstructed maps are extended to the maximum coverage area. By inspecting three significant rain events, we show an improvement of rain rate estimation over CMN or radar alone, almost uniformly, both for instantaneous spatial measurements, as well as in calculating total accumulated rainfall. These new improved 2-D rainfall maps, and the accurate rainfall measurements over large areas at sub-hourly time scales, will allow for improved understanding, initialization and calibration of hydrological and meteorological models necessary, mainly, for water resource management and planning.
Radiation belt data assimilation of a moderate storm event using a magnetic field configuration from the physics-based RAM-SCB model
Authors: Yu Y. , Koller J. , Jordanova V. K. , Zaharia S. G. , Godinez H. C.
Published: May 2014

Abstract. Data assimilation using Kalman filters provides an effective way of understanding both spatial and temporal variations in the outer electron radiation belt. Data assimilation is the combination of in situ observations and physical models, using appropriate error statistics to approximate the uncertainties in both the data and the model. The global magnetic field configuration is one essential element in determining the adiabatic invariants for the phase space density (PSD) data used for the radiation belt data assimilation. The lack of a suitable global magnetic field model with high accuracy is still a long-lasting problem. This paper employs a physics-based magnetic field configuration for the first time in a radiation belt data assimilation study for a moderate storm event on 19 December 2002. The magnetic field used in our study is the magnetically self-consistent inner magnetosphere model RAM-SCB, developed at Los Alamos National Laboratory (LANL). Furthermore, we apply a cubic spline interpolation method in converting the differential flux measurements within the energy spectrum, to obtain a more accurate PSD input for the data assimilation than the commonly used linear interpolation approach. Finally, the assimilation is done using an ensemble Kalman filter (EnKF), with a localized adaptive inflation (LAI) technique to appropriately account for model errors in the assimilation and improve the performance of the Kalman filter. The assimilative results are compared with results from another assimilation experiment using the Tsyganenko 2001S (T01S) magnetic field model, to examine the dependence on a magnetic field model. Results indicate that the data assimilations using different magnetic field models capture similar features in the radiation belt dynamics, including the temporal evolution of the electron PSD during a storm and the location of the PSD peak. The assimilated solution predicts the energy differential flux to a relatively good degree when compared with independent LANL-GEO in situ observations. A closer examination suggests that for the chosen storm event, the assimilation using the RAM-SCB predicts a better flux at most energy levels during storm recovery phase but is slightly worse in the storm main phase than the assimilation using the T01S model.
Soil CO2 efflux from mountainous windthrow areas: dynamics over 12 years post-disturbance
Authors: Mayer M. , Matthews B. , Schindlbacher A. , Katzensteiner K.
Published: May 2014

Abstract. Windthrow driven changes in carbon (C) allocation and soil microclimate can affect soil carbon dioxide (CO2) efflux (Fsoil) of forest ecosystems. Although Fsoil is the dominant C flux following stand-replacing disturbance, the effects of catastrophic windthrow on Fsoil are still poorly understood. We measured Fsoil at a montane mixed forest site and at a subalpine spruce forest site from 2009 until 2012. Both sites consisted of undisturbed forest stands and two adjacent windthrow areas which differed in time since disturbance. The combination of chronosequence and direct time-series approaches enabled us to investigate Fsoil dynamics over 12 years post-disturbance. In the initial phase after disturbance (1–6 years), Fsoil rates did not differ significantly from those of the undisturbed stands, but in the later phase (9–12 years after disturbance) Fsoil rates were significantly higher than corresponding undisturbed stand values. The higher Fsoil rates in the later phase post-disturbance are likely explained by a dense vegetation cover and correspondingly higher autotrophic respiration rates. Soil temperature increased significantly following windthrow (by 2.9–4.8 °C) especially in the initial phase post-disturbance when vegetation cover was sparse. A significant part (20–36%) of Fsoil from the windthrow areas was thus attributed to disturbance induced changes in soil temperature. According to our estimates, ~500 to 700 g C m−2yr−1 are released via Fsoil from south-facing forest sites in the Austrian Calcareous Alps in the initial 6 years after windthrow. With high game pressure suppressing primary production in these areas, post-disturbance loss of ecosystem C to the atmosphere is likely to be substantial unless management is proactive in regenerating such sites. An increase in the frequency of forest disturbance by windthrow could therefore decrease soil C stocks and positively feedback on rising atmospheric CO2 concentrations.
Trimethylamine emissions in animal husbandry
Authors: Sintermann J. , Schallhardt S. , Kajos M. , Jocher M. , Bracher A. , Münger A. , Johnson D. , Neftel A. , Ruuskanen T.
Published: May 2014

Abstract. Degradation of plant material by animals is an important transformation pathway in the nitrogen (N) cycle. During the involved processes, volatile reduced alkaline nitrogen compounds, mainly ammonia (NH3) and aliphatic amines such as trimethylamine (TMA), are formed. Today, animal husbandry is estimated to constitute a main source of aliphatic amines into the atmosphere with TMA being the main emitted compound. Here, we show how the interaction between faeces and urine in animal production systems provides the primary source for agricultural TMA emissions. Excreted urine contains large quantities of urea and TMA-N-oxide, which are transformed into NH3 and TMA, respectively, via enzymatic processes provided by microbes present in faeces. TMA emissions from areas polluted with urine-faeces mixture are on average in the order of 10 to 50 nmol m−2s−1. Released amines promote secondary aerosol particle formation in the agricultural emission plume. The atmospheric lifetime of TMA, which was estimated to be in the order of 30 to 1000 s, is determined by the condensation on aerosol particles.
Factors controlling shell carbon isotopic composition of land snail Acusta despecta sieboldiana estimated from lab culturing experiment
Authors: Zhang N. , Yamada K. , Suzuki N. , Yoshida N.
Published: May 2014

Abstract. The carbon isotopic composition (δ13C) of land snail shell carbonate derives from three potential sources: diet, atmospheric CO2, and ingested carbonate (limestone). However, their relative contributions remain unclear. Under various environmental conditions, we cultured one land snail species, Acusta despecta sieboldiana collected from Yokohama, Japan, and confirmed that all of these sources affect shell carbonate δ13C values. Herein, we consider the influences of metabolic rates and temperature on the carbon isotopic composition of the shell carbonate. Based on previous works and on results obtained in this study, a simple but credible framework is presented for discussion of how each source and environmental parameter can affect shell carbonate δ13C values. According to this framework and some reasonable assumptions, we have estimated the contributions of different carbon sources for each snail individual: for cabbage (C3 plant) fed groups, the contributions of diet, atmospheric CO2 and ingested limestone respectively vary as 66–80%, 16–24%, and 0–13%. For corn (C4 plant) fed groups, because of the possible food stress (lower consumption ability of C4 plant), the values vary respectively as 56–64%, 18–20%, and 16–26%. Moreover, we present new evidence that snails have discrimination to choose C3 and C4 plants as food. Therefore, we suggest that food preferences must be considered adequately when applying δ13C in paleo-environment studies. Finally, we inferred that, during egg laying and hatching of our cultured snails, carbon isotope fractionation is controlled only by the isotopic exchange of the calcite–HCO3−–aragonite equilibrium.
Accumulation of nitrogen and organic matter during primary succession of Leymus arenarius dunes on the volcanic island Surtsey, Iceland
Authors: Stefansdottir G. , Aradottir A. L. , Sigurdsson B. D.
Published: May 2014

Abstract. The volcanic island of Surtsey has been a natural laboratory where the primary succession of flora and fauna has been monitored, since it emerged from the N-Atlantic Ocean in 1963. We quantified the accumulation rates of nitrogen (N) and soil organic matter (SOM) in a 37 year long chronosequence of Leymus arenarius dunes in order to illuminate the spatiotemporal patterns in their build-up in primary succession. The Leymus dune area, volume and height grew exponentially over time. Aboveground plant biomass, cover or number of shoots per unit area did not change significantly with time, but root biomass accumulated with time, giving a root-shoot ratio of 19. The dunes accumulated on average 6.6 kg N ha−1 year−1, which was 3.5 times more than is received annually by atmospheric deposition. The extensive root system of Leymus seems to effectively retain and accumulate large part of the annual N deposition, not only deposition directly on the dunes but also from the adjacent unvegetated areas. SOM per unit area increased exponentially with dune age, but the accumulation of roots, aboveground biomass and SOM was more strongly linked to soil N than time: 1 g m−2 increase in soil N led on the average to 6 kg C m−2 increase in biomass and SOM. The Leymus dunes, where most of the N has been accumulated, will therefore probably act as hot-spots for further primary succession of flora and fauna on the tephra sands of Surtsey.
High-resolution hydraulic parameter maps for surface soils in tropical South America
Authors: Marthews T. R. , Quesada C. A. , Galbraith D. R. , Malhi Y. , Mullins C. E. , Hodnett M. G. , Dharssi I.
Published: May 2014

Abstract. Modern land surface model simulations capture soil profile water movement through the use of soil hydraulics sub-models, but good hydraulic parameterisations are often lacking, especially in the tropics. We present much-improved gridded data sets of hydraulic parameters for surface soil for the critical area of tropical South America, describing soil profile water movement across the region to 30 cm depth. Optimal hydraulic parameter values are given for the Brooks and Corey, Campbell, van Genuchten–Mualem and van Genuchten–Burdine soil hydraulic models, which are widely used hydraulic sub-models in land surface models. This has been possible through interpolating soil measurements from several sources through the SOTERLAC soil and terrain data base and using the most recent pedotransfer functions (PTFs) derived for South American soils. All soil parameter data layers are provided at 15 arcsec resolution and available for download, this being 20x higher resolution than the best comparable parameter maps available to date. Specific examples are given of the use of PTFs and the importance highlighted of using PTFs that have been locally parameterised and that are not just based on soil texture. We discuss current developments in soil hydraulic modelling and how high-resolution parameter maps such as these can improve the simulation of vegetation development and productivity in land surface models.
Assessing the CAM5 physics suite in the WRF-Chem model: implementation, resolution sensitivity, and a first evaluation for a regional case study
Authors: Ma P.-L. , Rasch P. J. , Fast J. D. , Easter R. C. , Gustafson Jr. W. I. , Liu X. , Ghan S. J. , Singh B.
Published: May 2014

Abstract. A suite of physical parameterizations (deep and shallow convection, turbulent boundary layer, aerosols, cloud microphysics, and cloud fraction) from the global climate model Community Atmosphere Model version 5.1 (CAM5) has been implemented in the regional model Weather Research and Forecasting with chemistry (WRF-Chem). A downscaling modeling framework with consistent physics has also been established in which both global and regional simulations use the same emissions and surface fluxes. The WRF-Chem model with the CAM5 physics suite is run at multiple horizontal resolutions over a domain encompassing the northern Pacific Ocean, northeast Asia, and northwest North America for April 2008 when the ARCTAS, ARCPAC, and ISDAC field campaigns took place. These simulations are evaluated against field campaign measurements, satellite retrievals, and ground-based observations, and are compared with simulations that use a set of common WRF-Chem parameterizations. This manuscript describes the implementation of the CAM5 physics suite in WRF-Chem, provides an overview of the modeling framework and an initial evaluation of the simulated meteorology, clouds, and aerosols, and quantifies the resolution dependence of the cloud and aerosol parameterizations. We demonstrate that some of the CAM5 biases, such as high estimates of cloud susceptibility to aerosols and the underestimation of aerosol concentrations in the Arctic, can be reduced simply by increasing horizontal resolution. We also show that the CAM5 physics suite performs similarly to a set of parameterizations commonly used in WRF-Chem, but produces higher ice and liquid water condensate amounts and near-surface black carbon concentration. Further evaluations that use other mesoscale model parameterizations and perform other case studies are needed to infer whether one parameterization consistently produces results more consistent with observations.
Decomposition analysis of water footprint changes in a water-limited river basin: a case study of the Haihe River basin, China
Authors: Zhi Y. , Yang Z. F. , Yin X. A.
Published: May 2014

Abstract. Decomposition analysis of water footprint (WF) changes, or assessing the changes in WF and identifying the contributions of factors leading to the changes, is important to water resource management. Instead of focusing on WF from the perspective of administrative regions, we built a framework in which the input-output (IO) model, the structural decomposition analysis (SDA) model and the generating regional IO tables (GRIT) method are combined to implement decomposition analysis for WF in a river basin. This framework is illustrated in the WF in Haihe River basin (HRB) from 2002 to 2007, which is a typical water-limited river basin. It shows that the total WF in the HRB increased from 4.3 × 1010 m3 in 2002 to 5.6 × 1010 m3 in 2007, and the agriculture sector makes the dominant contribution to the increase. Both the WF of domestic products (internal) and the WF of imported products (external) increased, and the proportion of external WF rose from 29.1 to 34.4%. The technological effect was the dominant contributor to offsetting the increase of WF. However, the growth of WF caused by the economic structural effect and the scale effect was greater, so the total WF increased. This study provides insights about water challenges in the HRB and proposes possible strategies for the future, and serves as a reference for WF management and policy-making in other water-limited river basins.
Simulated melt rates for the Totten and Dalton ice shelves
Authors: Gwyther D. E. , Galton-Fenzi B. K. , Hunter J. R. , Roberts J. L.
Published: May 2014

Abstract. The Totten Glacier is rapidly losing mass. It has been suggested that this mass loss is driven by changes in oceanic forcing; however, the details of the ice–ocean interaction are unknown. Here we present results from an ice shelf–ocean model of the region that includes the Totten, Dalton and Moscow University ice shelves, based on the Regional Oceanic Modeling System for the period 1992–2007. Simulated area-averaged basal melt rates (net basal mass loss) for the Totten and Dalton ice shelves are 9.1 m ice yr−1 (44.5 Gt ice yr−1) and 10.1 m ice yr−1 (46.6 Gt ice yr−1), respectively. The melting of the ice shelves varies strongly on seasonal and interannual timescales. Basal melting (mass loss) from the Totten ice shelf spans a range of 5.7 m ice yr−1 (28 Gt ice yr−1) on interannual timescales and 3.4 m ice yr−1 (17 Gt ice yr−1) on seasonal timescales. This study links basal melt of the Totten and Dalton ice shelves to warm water intrusions across the continental shelf break and atmosphere–ocean heat exchange. Totten ice shelf melting is high when the nearby Dalton polynya interannual strength is below average, and vice versa. Melting of the Dalton ice shelf is primarily controlled by the strength of warm water intrusions across the Dalton rise and into the ice shelf cavity. During periods of strong westward coastal current flow, Dalton melt water flows directly under the Totten ice shelf further reducing melting. This is the first such modelling study of this region to provide a valuable framework for directing future observational and modelling efforts.
Physical forcing and physical/biochemical variability of the Mediterranean Sea: a review of unresolved issues and directions for future research
Authors: Malanotte-Rizzoli P. , Artale V. , Borzelli-Eusebi G. L. , Brenner S. , Crise A. , Gacic M. , Kress N. , Marullo S. , Ribera d'Alcalà M. , Sofianos S. , Tanhua T. , Theocharis A. , Alvarez M. , Ashkenazy Y. , Bergamasco A. , Cardin V. , Carniel S. , Civitarese G. , D'Ortenzio F. , Font J. , Garcia-Ladona E. , Garcia-Lafuente J. M. , Gogou A. , Gregoire M. , Hainbucher D. , Kontoyannis H. , Kovacevic V. , Kraskapoulou E. , Kroskos G. , Incarbona A. , Mazzocchi M. G. , Orlic M. , Ozsoy E. , Pascual A. , Poulain P.-M. , Roether W. , Rubino A. , Schroeder K. , Siokou-Frangou J. , Souvermezoglou E. , Sprovieri M. , Tintoré J. , Triantafyllou G.
Published: May 2014

Abstract. This paper is the outcome of a workshop held in Rome in November 2011 on the occasion of the 25th anniversary of the POEM (Physical Oceanography of the Eastern Mediterranean) program. In the workshop discussions, a number of unresolved issues were identified for the physical and biogeochemical properties of the Mediterranean Sea as a whole, i.e., comprising the Western and Eastern sub-basins. Over the successive two years, the related ideas were discussed among the group of scientists who participated in the workshop and who have contributed to the writing of this paper. Three major topics were identified, each of them being the object of a section divided into a number of different sub-sections, each addressing a specific physical, chemical or biological issue: 1. Assessment of basin-wide physical/biochemical properties, of their variability and interactions. 2. Relative importance of external forcing functions (wind stress, heat/moisture fluxes, forcing through straits) vs. internal variability. 3. Shelf/deep sea interactions and exchanges of physical/biogeochemical properties and how they affect the sub-basin circulation and property distribution. Furthermore, a number of unresolved scientific/methodological issues were also identified and are reported in each sub-section after a short discussion of the present knowledge. They represent the collegial consensus of the scientists contributing to the paper. Naturally, the unresolved issues presented here constitute the choice of the authors and therefore they may not be exhaustive and/or complete. The overall goal is to stimulate a broader interdisciplinary discussion among the scientists of the Mediterranean oceanographic community, leading to enhanced collaborative efforts and exciting future discoveries.
Analysis of consumer behavior at chocolate purchase
Authors: Kozelová Dagmar , Matejková Eva , Fikselová Martina , Dékányová Judita
Published: May 2014

At food purchase consumer is affected by several factors. In this work analysis of consumer behavior at chocolate purchase was performed involving 277 respondents. Statistical testing of results was performed by Chi - Square statistic, correlations have been tested with use of the Cramer's coefficient. It was found, that 86% of respondents consume chocolate. Factors affecting respondents at purchase were recommendations of friends, acquaintances (32%), brand of chocolate (24%), price (16%), personal experience (12%), health restrictions and allergies (11%). Less important factors when choosing chocolates are flavor (4%), nutritional quality (3%), country of origin (2%) and chocolate packaging (1%). In the consumption of chocolate moderate correlation among various categories of economic activity of respondents was confirmed. Chocolate was consumed mainly by respondents whose monthly income ranges from 801 to 1001 €. We found that consumers prefer milk chocolate followed by dark and white at the end. In terms of gender the most commonly was chocolate consumed by women, once to three times a week. The same frequency of chocolate consumption dominates at the categories of students and employee. Expenses frequently spent to buy chocolates were from 1-3 € per week by young people (18-23 years) and middle age generation of people (46-55 years).
Examination of heat treatments at preservation of grape must
Authors: Korzenszky Péter , Molnár Erik
Published: May 2014

Heat treatment is a well-known process in food preservation. It is made to avoid and to slow down food deterioration. The process was developed by Louise Pasteur French scientist to avoid late among others wine further fermentation. The different heat treatments influence the shelf life in food production. In our article we present the process of grape must fermentation, as grape must is the base material of wine production. The treatment of harvested fresh grape juice has a big influence on end product quality. It is our experiments we examined the same grape must with four different methods in closed and in open spaces to determine CO2 concentration change. There are four different methods for treatment of grape juice: boiling, microwave treatment, treatment by water bath thermostat and a control without treatment. As a result of the comparison it can be stated that the heat treatment delays the start of fermentation, thereby increasing shelf life of grape must. However, no significant differences were found between two fermentation of heat-treated grape must by the microwave and water-bath thermostat. The different heat treatment of grape must base materials was done at the laboratory in Faculty of Mechanical Engineering of Szent István University. The origin of the table grapes used for the examination was Gödöllő-hillside.
Amino acids and fatty acids profile of chia (Salvia hispanica L.) and flax (Linum usitatissimum L.) seed
Authors: Nitrayová Soňa , Brestenský Matej , Heger Jaroslav , Patráš Peter , Rafay Ján , Sirotkin Alexander
Published: May 2014

The seeds of most plants are rich in various nutrients and can provide a lot of useful health benefits. The objective of this study was to determine and compare differences in fat, fatty acids, crude protein and amino acids concentrations for chia and flax seeds. Study was carried out using brown and gold seeds of Flax (Linum usitatissimum L.) and Chia (Salvia hispanica L.). The mean protein content in tested seeds ranged from 211.8 to 252.5 g/kg dry matter and in chia seed was about 13.10% higher than the average value of crude protein content in brown and gold flax seed (223.25 g/kg dry matter). Differences in the content of individual amino acids among the seeds were not statistically significant (P <0.05), except that for glutamic acid. Percentage of the essential to the total amino acids, which is considered as indicator of protein quality, was 37.87%, 33.76% and 35.18%, for chia, brown and gold flax seed respectively, which demonstrates the high quality of these proteins. The average fat content of flax seeds was about 71.42 g/kg higher than that in chia seed (321.37 g/kg dry matter). The fatty acids composition showed the presence of palmitic, stearic, oleic, linoleic, α- linolenic and arachidic fatty acids in all tested samples. The α-linolenic acid constitutes on average 54.38% of the total fatty acids of flax seeds and 63.79% of chia seed, and for linoleic acid it was 15.30% and 18.89%. All seeds had low n-6 PUFA / n-3 PUFA ratio. Results of our study confirmed the excellent quality of protein and fat in chia seed, brown and gold flax seed samples. There was no significant effect of the flax seed coat colour for all measured values. Chia seed is the richest of n-3 PUFA α-linolenic fatty acid in the vegetable world. Both, flax seed and chia seed are the good choice of healthy food to maintain a balanced serum lipid profile. It must be pointed that flax seeds must be ground to release their nutrients, but chia seeds do not.
Monitoring of color and pH in muscles of pork leg (m. adductor and m. semimembranosus)
Authors: Bednářová Martina , Kamení­k Josef , Sláková Alena , Pavlí­k Zdeněk , Tremlová Bohuslava
Published: May 2014

In order to identify PSE pork meat, pH and color testing was performed directly in a cutting plant (72 hours post mortem) in this research. Specifically pork leg muscles musculi adductor (AD) and semimembranosus (SM) from five selected suppliers (A, B, C, D, E) were examined. Twenty samples of meat for each muscle were examined from each supplier. The measured pH values ranged from 5.43 to 5.63, and the L* values from 46.13 to 57.18. No statistically significant differences in pH values and color were detected among the various suppliers with the exception of the a* and b* parameters for two suppliers, namely A and B (p<0.01). On the contrary, a statistically significant difference (p<0.5) was recorded between individual muscles (AD/SM) across all the suppliers (A, B, C, D, E) with the exception of a* parameter from suppliers B, C, D, E, and pH values for the E supplier. Our results revealed that individual muscles differ in values of pH and color. In comparison with literature, pH and lightness L* values in musculus adductor point to PSE (pale, soft and exudative) meat, while the values of musculus semimebranosus to RFN (red, firm and non-exudative). Use of PSE meat in production of meat products can cause several problems. In particular, it causes light color, low water-holding capacity, poor fat emulsifying ability, lower yield, granular or crumbly texture and poor consistency of the finished product. Therefore classification of the meat directly cutting plant may be possible solution for this problem. The finished product pruduces from muscles of musculi semimembranosus can obtain better quality than the finished product from musculi adductor.