176 research outputs found

    The influence of sources in violent news on fright and worry responses of children in the Netherlands

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    Contains fulltext : 233823.pdf (Publisher’s version ) (Open Access)Children display fright and worry responses to violent news. Including involved children, non-involved children or experts as sources in children's news is assumed to reduce these negative effects. However, exemplification theory gives reason to question whether particularly the use of involved children indeed has a reassuring effect. To test this, an experiment was conducted among 237 children (8-13 y/o). They were randomly exposed to a news video containing (1) involved children as source, (2) non-involved children, or (3) adult experts. Fright and worry responses were measured both before and after exposure. Results showed that the inclusion of involved children as a source significantly increased worry responses, but did not affect fright responses. Non-involved child sources significantly reduced fright and worry responses. Expert sources reduced children’s fright responses, but did not change feelings of worry. These insights can inform news producers on how to alleviate the effects of covering violent events in news.02 juni 202110 p

    Una década de activa participación en Operaciones de Paz

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    Reseñar un importante aspecto de la política exterior desarrollada por Argentina durante los últimos diez años, caracterizada por una intensa y continuada participación en las denominadas Operaciones de Mantenimiento de la Paz (en adelante OOMP) que posteriormente fuera ampliada a las Operaciones de Paz (en adelante OOP) y que en opinión de la doctrina mayoritaria -a la cual adhieren los ponentes- significaron un gran rédito para el prestigio internacional del país. (Párrafo extraído del texto a modo de resumen)Comisión 1. La participación argentina en organismos multilateralesInstituto de Relaciones Internacionale

    Una década de activa participación en Operaciones de Paz

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    Reseñar un importante aspecto de la política exterior desarrollada por Argentina durante los últimos diez años, caracterizada por una intensa y continuada participación en las denominadas Operaciones de Mantenimiento de la Paz (en adelante OOMP) que posteriormente fuera ampliada a las Operaciones de Paz (en adelante OOP) y que en opinión de la doctrina mayoritaria -a la cual adhieren los ponentes- significaron un gran rédito para el prestigio internacional del país. (Párrafo extraído del texto a modo de resumen)Comisión 1. La participación argentina en organismos multilateralesInstituto de Relaciones Internacionale

    Recolha de água e retenção de humidade do solo

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    Water harvesting and soil moisture retention

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    Electromagnetic suspension and levitation

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    Regional Geoid and Gravity Field from a Combination of Airborne and Satellite Data in Dronning Maud Land, East Antarctica

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    SummaryRecently, a variety of gravity observations in Antarctica has become available through extensive e orts of airbornesurveys. Aircrafts serving as multi-instrumentation platforms provide measurements on gravity, bedrocktopography, ice surface topography and ice thickness. Collected datasets are valuable in terms of resolution andhomogeneity, which make them suitable for studying regional geoid determination in selected Antarctic regions.Within this context the German joint project VISA provided an excellent database for improving the regionalgeoid by combining gravity and topographic data from aerogeophysical observations with long-wavelength informationfrom global gravity eld models. Using the remove-compute-restore technique in conjunction withleast-squares collocation a regional geoid for Dronning Maud Land, East Antarctica, will be presented. A signalthreshold of up to 6 m added to the global model that was used as a basis can be expected. The accuracy ofthe regional geoid will be estimated to be at the level of 15 cm.Citation: J. Muller, S. Riedel, M. Scheinert, M. Horwath, R. Dietrich, D. Steinhage, H. Anschutz, W. Jokat(2007), RegionalGeoid and Gravity Field from a Combination of Airborne and Satellite Data in Dronning Maud Land, East Antarctica { OnlineProceedings of the 10th ISAES, edited by A.K. Cooper and C.R. Raymond et al., USGS Open-File Report 2007-xxx, ExtendedAbstract yyy, 1-4.IntroductionThe new datasets provided by the satellite missions CHAMP, GRACE and GOCE (to be launched by theend of 2007) enable a homogeneous determination of the gravity eld. Furthermore, in the polar regions icesurface heights could be determined in a similar quality by ICESat. These new satellite data shall be validatedand densi ed by the German joint project VISA (Validation, Densi cation and Interpretation of Satellite Datafor the Determination of Magnetic Field, Gravity Field, Ice Mass Balance and Structure of the Earth Crust inAntarctica, uitilizing Airborne and Terrestrial Measurements) of TU Dresden and AWI Bremerhaven.For this purpose western and central Dronning Maud Land (DML), East Antarctica, were chosen as areaof investigation. Airborne as well as terrestrial observation campaigns were carried out to provide appropriatedatasets on height and height changes, gravity and gravity changes, magnetics, glaciology and seismology. Incombination with the satellite data these measurements will be applied to yield more detailed models of thegravity eld and the regional geoid, of the crustal structure and litosphere dynamics and of the dynamics andmass balance of the Antarctic ice sheet in the working area.Observation campaignsBetween 2001 and 2005 four airborne observation campaigns and two terrestrial observation campaigns werecarried out in western and central DML in order to conduct geodetic and geophysical measurements (Fig. 1,left). The scienti c program of the aerogeophysical campaigns for the observation of the gravity eld, magnetic eld, ice surface height and ice thickness (Radio Echo Sounding (RES)) contains more than 350 ight-hourswith a line-spacing between 10 and 20 kilometers. The terrestrial eld work took place at two di erent areas,during the season 2003/04 at Schirmacher Oasis - Potsdam Glacier - Wohlthat Mountains and one year later(season 2004/05) at Heimefrontfjella - Kirwanveggen. GPS and seismometer stations on bedrock were installed,kinematic GPS pro les, relative gravimetry on ice and ground penetrating radar (GPR) measurements werecarried out as well as samplings of rn cores and snow pits (Anschutz et al., 2007; Anschutz et al., 2006;Scheinert et al., 2005; Nixdorf et al., 2004).Regional Geoid ImprovementCombining satellite observations from CHAMP and GRACE with terrestrial data, high-resolution models ofthe Earth gravity eld have been obtained. Latest examples of these combination models are EIGEN-CG03C, EIGEN-GL04C (Forste et al., 2005; Forste et al., 2006) and GGM02C (Tapley et al., 2005). In Antarctica, thedetermination of the global gravity eld is problematic becausen due to the remoteness (often inaccessibility)and harsh conditions the terrestrial gravity data coverage features very large gaps. Only for a few smallerregions ground-based or airborne measured gravity was included into the combination. In order to improve theterrestrial gravity coverage and to determine the Antarctic geoid, the IAG Commission Project 2.4 "AntarcticGeoid" (chaired by M. Scheinert) was set into action, which is closely linked to SCAR Expert Group on GeodeticInfrastructure in Antarctica (GIANT) project 3 "Physical Geodesy". An overview on the situation is given in(Scheinert, 2005), and the strategy of regional geoid improvement is discussed in (Scheinert et al., 2007b) for thePrince Charles Mountains region, East Antarctica (PCMEGA), as well as for Palmer Land, Antarctic Peninsula(Scheinert et al., 2007a).Within this context, the VISA observation campaigns de-Figure 2: Free-air Anomalies (preliminary resultswith a spatial resolution of 14 kilometers)scribed above provide an excellent database for the validationof the gravity eld and, more importantly, for the determinationand improvement of the regional geoid. Fig. 2 showspreliminary results for the free-air anomalies derived from airbornemeasurements over the western and central DML witha resolution of 14 kilometer (Riedel and Jokat, 2007). Comparedwith the subglacial topography (Fig. 3, left panel) thestrong correlation between these two datasets is clearly visible.The right panel of Fig. 3 shows the ice surface heightin the area of investigation. The datasets of Fig. 3 a ord toderive the ice-thickness, which will be needed in addition tothe subglacial topography for the computation of an improvedgeoid. The high resolution of these datasets make them muchmore suitable than BEDMAP data (Lythe et al., 2000), whichwere a valuable source of information prior to the VISA radarobservations in DML.Especially in Antarctica problems occur when satellite observationsfrom CHAMP and GRACE up to a certain spherical harmonic degree (typically 120) should be combined with terrestrial data. Geophysically extrapolated gravity anomalies do not necessaily reect the actualgravity eld in Antarctica, though they are inevitable to provide a globally complete data coverage neededfor the solution of the closed surface integrals. For this reason, shorter wavelength information (higher thanspherical harmonic degree 120) is unreliable for most Antarctic areas (Fig. 1, right). This evinces when comparingthe gravity anomalies from EIGEN-GL04C for a harmonic window (degrees 121 to 360) (Fig. 1, right)with the free-air anomalies derived from VISA airborne measurements (Fig. 2). While a higher correlation canbe seen near the coastline, it diminishes in the southern part of DML.For the calculation of the regional geoid the remove-compute-restore technique (RCRT) was applied, whichis discussed in detail e.g. in (Forsberg and Tscherning, 1997) and (Sjoberg, 2005) and which was also usedin the PCMEGA case (Scheinert et al., 2007b). In the remove step, a long-wavelength part (predicted by aglobal gravity eld model) and a short-wavelength part (predicted by topography) are removed from the originalgravity data. In the compute step, the obtained band-pass ltered gravity anomalies are transformed into geoidheights, using least-squares collocation in this study. Least-squares collocation o ers the advantage of providingerror estimates for the resulting geoid. After having carried out the compute step, the long-wavelength part andthe short-wavelength part are restored in the geoid. For the computations, we could make use of the programpackage GRAVSOFT (Forsberg et al., 2003; Tscherning, 1974), which o ers a variety of tools for the geodeticgravity eld modelling.ConclusionCombining gravity and topographic data from VISA aerogeophysical campaigns with a global gravity eldmodel a regional geoid for Dronning Maud Land, East Antarctica, will be presented. Studies in other regionsof Antarctica (Scheinert et al., 2007a; Scheinert et al., 2007b) have shown that a signal threshold of up to 6 mto the global gravity eld model that was used as a basis can be expected when comparing the improved geoidwith the global model up to spherical harmonic degree 120. The accuracy of the regional geoid is estimated tobe at the level of 15 cm. Considering the current data situation in Antarctica, the accuracy level of 1 dm is arealistic and appropriate goal for this area of the world. The data coverage in Antarctica will most likely besubject to major improvements when further airborne surveys are carried out. The International Polar Year2007/ 2008 provides a reasonable framework for international and interdisciplinary cooperation in that eld.SCAR-GIANT project 3 "Physical Geodesy" and IAG Commission Project 2.4 "Antarctic Geoid" work towardsthe goal of closing the gaps in the gravity data coverage and at improving the geoid in Antarctica

    A social identity perspective on conformity to cyber aggression among early adolescents on WhatsApp

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    Cyber aggressive behaviors such as nonconsensual image sharing, nasty comments, and social exclusion frequently take place on WhatsApp. These behaviors often involve group processes, where adolescents conform to peers’ behaviors. WhatsApp is pre-eminently suited for group-communication among adolescents, and, thus, may facilitate conformity to such behaviors. However, research on conformity on WhatsApp is scarce. Therefore, the aim of this study was to examine if and how the social identity perspective on group behavior may explain cyber aggression on WhatsApp. Specifically, we examined how social identification relates to conformity to cyber aggression on WhatsApp. In a preregistered survey, 647 early adolescents answered questions about social identification with group members and conformity to behavior of a WhatsApp group. Hierarchical multiple regression and moderated mediation analyses point toward an indirect, positive relation between the centrality component of social identification and conformity to cyber aggression, mediated by perceived social pressure to conform. These findings contribute to the literature by extending the social identity perspective to conformity on WhatsApp. Further exploration of this research line within the field of cyber aggression is warranted, because this can help improve applied interventions to reduce conformity to cyber aggression

    Testing a first online intervention to reduce conformity to cyber aggression in messaging apps

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    Early adolescents frequently use mobile messaging apps to communicate with peers. The popularity of such messaging apps has a critical drawback because it increases conformity to cyber aggression. Cyber aggression includes aggressive peer behaviors such as nasty comments, nonconsensual image sharing, and social exclusion, to which adolescents subsequently conform. Recent empirical research points to peer group norms and reduced accountability as two essential determinants of conformity to cyber aggression. Therefore, the current study aimed to counteract these two determinants in a 2 (peer group norms counteracted: yes, no) x 2 (reduced accountability counteracted: yes, no) design. We created four intervention conditions that addressed adolescents' deficits in information, motivation, and behavioral skills. Depending on the condition (peer group norms, reduced accountability, combination, or control), we first informed participants about the influence of the relevant determinant (e.g., peer group norms). Subsequently, participants performed a self-persuasion task and formulated implementation-intentions to increase their motivation and behavioral skills not to conform to cyber aggression. Effectiveness was tested with a messaging app paradigm and self-report among a sample of 377 adolescents (Mage = 12.99, SDage = 0.84; 53.6% boys). Factorial ANCOVAs revealed that none of the intervention conditions reduced conformity to cyber aggression. Moreover, individual differences in susceptibility to peer pressure or inhibitory control among adolescents did not moderate the expected relations. Therefore, there is no evidence that our intervention effectively reduces conformity to cyber aggression. The findings from this first intervention effort point to the complex relationship between theory and practice. Our findings warrant future research to develop potential intervention tools that could effectively reduce conformity to cyber aggression
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