954 resultados para VARIABLES
Resumo:
Este trabajo pretende replicar con muestras españolas un estudio americano diseñado para evaluar las relaciones entre el rasgo Búsquesa de Sensaciones, Extraversión, Neuroticismo y Psicoticismo, con el interés por la contemplación o lectura de sucesos violentos, morbosos y sexuales en los medios de comunicación (o reales). El estudio se realizó a partir de inventarios autoinformados de curiosidad morbosa, cuestionarios de personalidad y autopuntuaciones de asistencia a películas pornográficas y de terror. Los resultados obtenidos informan de una relación positiva entre las escalas de Búsqueda de Sensaciones (EBS) y las escalas de Curiosidad Morbosa (CTM-CTS). Ello sugiere como hipótesis que los altos buscadores de sensaciones podrían estar interesados en estímulos que aumentan la actividad del sistema central de catecolaminas. Para ello se parte de hallazgos experimentales previos que apuntan que películas morbosas de terror o sexuales aumentan los niveles de las catecolaminas periféricas.
Resumo:
El trabajo que se presenta en este artículo se sitúa en el contexto bilingüe de la provincia de Lleida en la que coexisten dos lenguas en contacto, el catalán y el castellano, si bien existe un predominio de uso familiar y escolar de la primera de ellas. En este contexto, nuestro estudio analiza cómo influyen en el rendimiento en matemáticas las variables del contexto educativo de condición lingüística familiar y situación socio-profesional de la familia, así como las variables individuales de conciente intelectual y autoconcepto matemático. Los resultados globales muestran, en primer lugar, la importancia del lenguaje como instrumento mediador de la enseñanza-aprendizaje de contenidos matemáticos, ya que el rendimiento de los alumnos en esta área curricular está en función del dominio y el uso de la lengua vehicular de la enseñanza —el catalán—. En segundo lugar, se constata una correlación significativa entre el rendimiento matemático y las variables individuales de cociente intelectual y el autoconcepto sobre el propio rendimiento matemático.
Resumo:
El presente trabajo muestra los resultados provisionales de un proyecto de viticultura de precisión, llevado a cabo entre la Universidad de Lleida y la empresa Codorníu, S.A., con el objeto de predecir el rendimiento, de forma localizada, de diferentes variedades de viña para la producción de vinos y cavas de calidad. Las variables de cultivo muestreadas de forma detallada han sido: número de yemas, número de brotes, número de racimos, peso de la poda, vigor del cultivo y cosecha del año anterior (2003). El vigor del cultivo se ha extraído de una imagen multiespectral Quickbird 2. Estas variables se han analizado en un modelo de regresión múltiple con la cosecha del año 2004 (variable dependiente), ofreciendo diferentes ajustes según la variedad considerada y variables incorporadas en el análisis.
Resumo:
We estimate how climate variables affect price and acreage of productive farmland using the Ricardian approach. Furthermore, we use our estimations to evaluate the joint effects of possible cli- mate changes within the time horizon of 2010 and 2050. Our results show that the price of rainfed land in Spain tends to increase but rainfed acreage decreases. On the other hand, the effect on irrigated farmland price and acreage presents some mixed results, however, in the long run the dominant pattern is clearly increasing for both prices and acreage.
Resumo:
We estimate the impact of the different climate variables on the value of Spanish farmland. We distinguish between irrigated and non-irrigated lands and use data on temperature, precipitations, physical and socioeconomic characteristics to measure these effects on farm prices and in the number of hectares of farmland. We conclude presenting the main results of our analysis, region by region, and examining the policies that could be more effective to prevent undesired effects.
Resumo:
Se han utilizado los datos procedentes de una red (array) sísmica situada en la isla Livingston para estudiar la evolución de las caídas de bloques de hielo en los frentes de los glaciares (calving). Pa rtiendo de que la causa fundamental de las caídas de bloques es el flujo del hielo, se ha estudiado la influencia de la temperatura ambiental, la variación del nivel de la marea, la humedad y la velocidad del viento sobre este fenómeno. Como principal conclusión se deduce que la temperatura ambiental es el factor que ejerce una mayor y más directa influencia sobre las caídas de los bloques de hielo.
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Interception requires precise estimation of time-to-contact (TTC) information. A long-standing view posits that all relevant information for extracting TTC is available in the angular variables, which result from the projection of distal objecs on to the retina. The diferent timing models rooted in this tradition have consequently relied on combining visual angle and its rate of expansion in diferent ways with tau being the most well-known solution for TTC...
Resumo:
Background: A holistic perspective on health implies giving careful consideration to the relationship between physical and mental health. In this regard the present study sought to determine the level of Positive Mental Health (PMH) among people with chronic physical health problems, and to examine the relationship between the observed levels of PMH and both physical health status and socio-demographic variables. Methods: The study was based on the Multifactor Model of Positive Mental Health (Lluch, 1999), which comprises six factors: Personal Satisfaction (F1), Prosocial Attitude (F2), Self-control (F3), Autonomy (F4), Problem-solving and Self-actualization (F5), and Interpersonal Relationship Skills (F6). The sample comprised 259 adults with chronic physical health problems who were recruited through a primary care center in the province of Barcelona (Spain). Positive mental health was assessed by means of the Positive Mental Health Questionnaire (Lluch, 1999). Results: Levels of PMH differed, either on the global scale or on specific factors, in relation to the following variables: age: global PMH scores decreased with age (r=-0.129; p=0.038); b) gender: men scored higher on F1 (t=2.203; p=0.028) and F4 (t=3.182; p=0.002), while women scored higher on F2 (t -3.086; p=0.002) and F6 (t=-2.744; p=0.007); c) number of health conditions: the fewer the number of health problems the higher the PMH score on F5 (r=-0.146; p=0.019); d) daily medication: polymedication patients had lower PMH scores, both globally and on various factors; e) use of analgesics: occasional use of painkillers was associated with higher PMH scores on F1 (t=-2.811; p=0.006). There were no significant differences in global PMH scores according to the type of chronic health condition. The only significant difference in the analysis by factors was that patients with hypertension obtained lower PMH scores on the factor Autonomy (t=2.165; p=0.032). Conclusions: Most people with chronic physical health problems have medium or high levels of PMH. The variables that adversely affect PMH are old age, polypharmacy and frequent consumption of analgesics. The type of health problem does not influence the levels of PMH. Much more extensive studies with samples without chronic pathology are now required in order to be able to draw more robust conclusions.
Resumo:
Between-country differences in medical and sociodemographic variables, and patient-related outcomes (PROs) before treatment might explain published variations of side effects after radical prostatecomy (RP) or radiotherapy (RAD) for prostate cancer (PCa). This hypothesis was tested among 1908 patients from the United States, Spain, and Norway. Significant between-country differences were observed for most factors investigated before treatment. The observations should be considered in comparison of the frequency and severity of internationally published studies. Background: In men with PCa, large variations of PROs after RP or high-dose RAD might be related to betweencountry differences of medical and sociodemographic variables, and differences in PROs before treatment in the sexual and urinary domains. Patients and Methods: In 1908 patients with localized PCa from Norway, the United States, or Spain, the relation between medical (prostate-specific antigen, Gleason score, cT-category) and sociodemographic variables (age, education, marital status) before treatment was investigated. Using the Expanded Prostate Cancer Index Composite questionnaire, PROs before treatment within the sexual and urinary domains were also considered. Results: Compared with the European patients, American patients were younger, fewer had comorbid conditions, and more had a high education level. Fifty-three percent of the US men eligible for RP had low-risk tumors compared with 42% and 31% among the Norwegian and the Spanish patients, respectively. Among the Spanish RAD patients, 54% had had low-risk tumors compared with 34% of the American and 21% of the Norwegian men planned for RAD, respectively. Compared with the European patients, significantly fewer US patients reported moderate or severe sexual dysfunction and related problems. In most subgroups, the number of patients with sexual or urinary dysfunction exceeded that of patients with bother related to the reported dysfunction. Conclusion: Statistically significant between-country differences were observed in medical and sociodemographic variables, and in PROs before treatment within the sexual and urinary domains. Large differences between reported dysfunction and related problems within the sexual and urinary domains indicate that dysfunction and bother should be reported separately in addition to calculation of summary scores. The documented differences, not at least regarding PROs, might in part explain the large variation of side effects after treatment evident in the medical literature
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Study of the changes in health habits of 105 cancer patients’ relatives and close friends after the diagnosis. The aim is to try to verify whether the knowledge of the disease has got some impact in the modification of their life styles. The emotional alterations influence in this change of behaviour has been analysed futhermore. An interview of own creation and HADS (Anxiety Hospital and Depression Scale of Zigmond and Snaith, 1983) instrument, in a Spanish and a Catalan version, were used with this aim. The results show that 21.1% of the participants presented positive changes in their health habits after the diagnosis of the relative or close friend and 11.5% showed negative changes. In relation to the role of the emotions, averages of anxiety (14,33; d.t.=4,98) and depressive (10,17; d.t.=4,93) symptoms were higher in those subjects who made negative changes than in those who did not make any change (9,32; d.t.=5,37 and 6,33; d.t.=4,64). In addition, the youngest participants, with more depressive symptoms and who visit the subject more often, are those who become more assets modifying health habits. The results suggest that emotional alterations, mainly depressive symptoms, are associated with negative change and, therefore, it would be suitable to lend some type of attention to these alterations in the population studied with the purpose of improving their present and future health
Resumo:
The CO2-laser-MAG hybrid welding process has been shown to be a productive choice for the welding industry, being used in e.g. the shipbuilding, pipe and beam manufacturing, and automotive industries. It provides an opportunity to increase the productivity of welding of joints containing air gaps compared with autogenous laser beam welding, with associated reductions in distortion and marked increases in welding speeds and penetration in comparison with both arc and autogenous laser welding. The literature study indicated that the phenomena of laser hybrid welding are mostly being studied using bead-on-plate welding or zero air gap configurations. This study shows it very clearly that the CO2 laser-MAG hybrid welding process is completely different, when there is a groove with an air gap. As in case of industrial use it is excepted that welding is performed for non-zero grooves, this study is of great importance for industrial applications. The results of this study indicate that by using a 6 kW CO2 laser-MAG hybrid welding process, the welding speed may also be increased if an air gap is present in the joint. Experimental trials indicated that the welding speed may be increased by 30-82% when compared with bead-on-plate welding, or welding of a joint with no air gap i.e. a joint prepared as optimum for autogenous laser welding. This study demonstrates very clearly, that the separation of the different processes, as well as the relative configurations of the processes (arc leading or trailing) affect welding performance significantly. These matters influence the droplet size and therefore the metal transfer mode, which in turn determined the resulting weld quality and the ability to bridge air gaps. Welding in bead-onplate mode, or of an I butt joint containing no air gap joint is facilitated by using a leading torch. This is due to the preheating effect of the arc, which increases the absorptivity of the work piece to the laser beam, enabling greater penetration and the use of higher welding speeds. With an air gap present, air gap bridging is more effectively achieved by using a trailing torch because of the lower arc power needed, the wider arc, and the movement of droplets predominantly towards the joint edges. The experiments showed, that the mode of metal transfer has a marked effect on gap bridgeability. Transfer of a single droplet per arc pulse may not be desirable if an air gap is present, because most of the droplets are directed towards the middle of the joint where no base material is present. In such cases, undercut is observed. Pulsed globular and rotational metal transfer modes enable molten metal to also be transferred to the joint edges, and are therefore superior metal transfer modes when bridging air gaps. It was also found very obvious, that process separation is an important factor in gap bridgeability. If process separation is too large, the resulting weld often exhibits sagging, or no weld may be formed at all as a result of the reduced interaction between the component processes. In contrast, if the processes are too close to one another, the processing region contains excess molten metal that may create difficulties for the keyhole to remain open. When the distance is optimised - i.e. a separation of 0-4 mm in this study, depending on the welding speed and beam-arc configuration - the processes act together, creating beneficial synergistic effects. The optimum process separation when using a trailing torch was found to be shorter (0-2 mm) than when a leading torch is used (2-4 mm); a result of the facilitation of weld pool motion when the latter configuration is adopted. This study demonstrates, that the MAG process used has a strong effect on the CO2-laser-MAG hybrid welding process. The laser beam welding component is relatively stable and easy to manage, with only two principal processing parameters (power and welding speed) needing to be adjusted. In contrast, the MAG process has a large number of processing parameters to optimise, all of which play an important role in the interaction between the laser beam and the arc. The parameters used for traditional MAG welding are often not optimal in achieving the most appropriate mode of metal transfer, and weld quality in laser hybrid welding, and must be optimised if the full range of benefits provided by hybrid welding are to be realised.