954 resultados para variables psicológicas
Resumo:
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.
Resumo:
In this study, a wrapper approach was applied to objectively select the most important variables related to two different anaerobic digestion imbalances, acidogenic states and foaming. This feature selection method, implemented in artificial neural networks (ANN), was performed using input and output data from a fully instrumented pilot plant (1 m 3 upflow fixed bed digester). Results for acidogenic states showed that pH, volatile fatty acids, and inflow rate were the most relevant variables. Results for foaming showed that inflow rate and total organic carbon were among the relevant variables, both of which were related to the feed loading of the digester. Because there is not a complete agreement on the causes of foaming, these results highlight the role of digester feeding patterns in the development of foaming
Resumo:
All social surveys suffer from different types of errors, of which one of the most studied is non-response bias. Non-response bias is a systematic error that occurs because individuals differ in their accessibility and propensity to participate in a survey according to their own characteristics as well as those from the survey itself. The extent of the problem heavily depends on the correlation between response mechanisms and key survey variables. However, non-response bias is difficult to measure or to correct for due to the lack of relevant data about the whole target population or sample. In this paper, non-response follow-up surveys are considered as a possible source of information about non-respondents. Non-response follow-ups, however, suffer from two methodological issues: they themselves operate through a response mechanism that can cause potential non-response bias, and they pose a problem of comparability of measure, mostly because the survey design differs between main survey and non-response follow-up. In order to detect possible bias, the survey variables included in non-response surveys have to be related to the mechanism of participation, but not be sensitive to measurement effects due to the different designs. Based on accumulated experience of four similar non-response follow-ups, we studied the survey variables that fulfill these conditions. We differentiated socio-demographic variables that are measurement-invariant but have a lower correlation with non-response and variables that measure attitudes, such as trust, social participation, or integration in the public sphere, which are more sensitive to measurement effects but potentially more appropriate to account for the non-response mechanism. Our results show that education level, work status, and living alone, as well as political interest, satisfaction with democracy, and trust in institutions are pertinent variables to include in non-response follow-ups of general social surveys. - See more at: https://ojs.ub.uni-konstanz.de/srm/article/view/6138#sthash.u87EeaNG.dpuf
Resumo:
El joc es converteix en un problema de salut quan la persona perd el control de la seva conducta, anteposant-ho a les seves obligacions socials i familiars. Diversos estudis sobre el joc demostren que és una conducta iniciada en l'adolescència. La prevenció en salut es mostra fonamental en aquesta etapa del desenvolupament del jove, moment en el qual s'estableixen patrons de conducta. El propòsit d'aquest treball és realitzar un programa de prevenció orientat a evitar el joc patològic en adolescents. Els seus objectius són: Prevenir conductes que deriven en joc patològic per a adolescents; reduir o limitar les hores de joc, fomentant conductes i activitats alternatives; i fomentar la integració i participació del jove al programa com a mitjà d'assimilació dels conceptes exposats i mantenir la seva atenció en el curs del programa. Aquest programa es basa en el model Precedeix i en la teoria Cognitiu-Social de Bandura. Està dirigit a joves de tots dos sexes, escolaritzats a Terrassa, d'entre 15 i 17 anys. Les variables d'interès són edat, sexe; edat, professió i situació social dels seus pares; entorn social, accés a internet. No es considerarà si el jove ha tingut problemes similars precedents. Constarà de sis sessions de 1h. en les quals s'explicaran les conseqüències del joc patològic i la forma d'adquisició d'aquesta conducta, la relació conductual del jove entorn del joc, els factors de risc i protecció que envolten al joc, i es fomentarà l'autoconcienciación del jove referent a la seva conducta, tenint també en compte el seu entorn social. Es realitzarà una sessió final evaluativa d'anàlisi de funcionament i avaluació del programa tant per part del jove com del ponent. Els resultats esperats de la implementació del programa són: Un millor control i coneixement del joc, reducció del temps de joc i el reconeixement de patrons de conducta inadequats per part del jove.
Resumo:
1. Digital elevation models (DEMs) are often used in landscape ecology to retrieve elevation or first derivative terrain attributes such as slope or aspect in the context of species distribution modelling. However, DEM-derived variables are scale-dependent and, given the increasing availability of very high-resolution (VHR) DEMs, their ecological relevancemust be assessed for different spatial resolutions. 2. In a study area located in the Swiss Western Alps, we computed VHR DEMs-derived variables related to morphometry, hydrology and solar radiation. Based on an original spatial resolution of 0.5 m, we generated DEM-derived variables at 1, 2 and 4 mspatial resolutions, applying a Gaussian Pyramid. Their associations with local climatic factors, measured by sensors (direct and ambient air temperature, air humidity and soil moisture) as well as ecological indicators derived fromspecies composition, were assessed with multivariate generalized linearmodels (GLM) andmixed models (GLMM). 3. Specific VHR DEM-derived variables showed significant associations with climatic factors. In addition to slope, aspect and curvature, the underused wetness and ruggedness indices modelledmeasured ambient humidity and soilmoisture, respectively. Remarkably, spatial resolution of VHR DEM-derived variables had a significant influence on models' strength, with coefficients of determination decreasing with coarser resolutions or showing a local optimumwith a 2 mresolution, depending on the variable considered. 4. These results support the relevance of using multi-scale DEM variables to provide surrogates for important climatic variables such as humidity, moisture and temperature, offering suitable alternatives to direct measurements for evolutionary ecology studies at a local scale.
Resumo:
Une Suisse polycentrique et multifonctionnelle ou du fédéralisme coopératif à la concurrence fiscale.
Resumo:
PURPOSE: We investigated association of hematological variables with specific fitness performance in elite team-sport players. METHODS: Hemoglobin mass (Hbmass) was measured in 25 elite field hockey players using the optimized (2 min) CO-rebreathing method. Hemoglobin concentration ([Hb]), hematocrit and mean corpuscular hemoglobin concentration (MCHC) were analyzed in venous blood. Fitness performance evaluation included a repeated-sprint ability (RSA) test (8 x 20 m sprints, 20 s of rest) and the Yo-Yo intermittent recovery level 2 (YYIR2). RESULTS: Hbmass was largely correlated (r = 0.62, P<0.01) with YYIR2 total distance covered (YYIR2TD) but not with any RSA-derived parameters (r ranging from -0.06 to -0.32; all P>0.05). [Hb] and MCHC displayed moderate correlations with both YYIR2TD (r = 0.44 and 0.41; both P<0.01) and RSA sprint decrement score (r = -0.41 and -0.44; both P<0.05). YYIR2TD correlated with RSA best and total sprint times (r = -0.46, P<0.05 and -0.60, P<0.01; respectively), but not with RSA sprint decrement score (r = -0.19, P>0.05). CONCLUSION: Hbmass is positively correlated with specific aerobic fitness, but not with RSA, in elite team-sport players. Additionally, the negative relationships between YYIR2 and RSA tests performance imply that different hematological mechanisms may be at play. Overall, these results indicate that these two fitness tests should not be used interchangeably as they reflect different hematological mechanisms.
Resumo:
En este documento se formula un modelo de predicción de la insolvencia a través de la combinación de diferentes variables cuantitativas extraídas de los estados contables de una muestra de empresas para los años 1994-1997. Partiendo del modelo de flexibilidad financiera de Donaldson, que es adaptado por Van Frederikslust a la predicción de la insolvencia, lo que aquí se expone es una aplicación a una muestra de empresas de los sectores textil y confección. Aunque los resultados no son alentadores, lo más importante es destacar cómo a través de una modelización de este tipo, probamos una formulación teórica del problema.
Resumo:
Objective: We used demographic and clinical data to design practical classification models for prediction of neurocognitive impairment (NCI) in people with HIV infection. Methods: The study population comprised 331 HIV-infected patients with available demographic, clinical, and neurocognitive data collected using a comprehensive battery of neuropsychological tests. Classification and regression trees (CART) were developed to btain detailed and reliable models to predict NCI. Following a practical clinical approach, NCI was considered the main variable for study outcomes, and analyses were performed separately in treatment-naïve and treatment-experienced patients. Results: The study sample comprised 52 treatment-naïve and 279 experienced patients. In the first group, the variables identified as better predictors of NCI were CD4 cell count and age (correct classification [CC]: 79.6%, 3 final nodes). In treatment-experienced patients, the variables most closely related to NCI were years of education, nadir CD4 cell count, central nervous system penetration-effectiveness score, age, employment status, and confounding comorbidities (CC: 82.1%, 7 final nodes). In patients with an undetectable viral load and no comorbidities, we obtained a fairly accurate model in which the main variables were nadir CD4 cell count, current CD4 cell count, time on current treatment, and past highest viral load (CC: 88%, 6 final nodes). Conclusion: Practical classification models to predict NCI in HIV infection can be obtained using demographic and clinical variables. An approach based on CART analyses may facilitate screening for HIV-associated neurocognitive disorders and complement clinical information about risk and protective factors for NCI in HIV-infected patients.
Resumo:
Some recent studies have characterized the stability of blood variables commonly measured for the Athlete Biological Passport. The aim of this study was to characterize the impact of different shipments conditions and the quality of the results returned by the haematological analyzer. Twenty-two healthy male subjects provided five EDTA tubes each. Four shipment conditions (24, 36, 48, 72 h) under refrigerated conditions were tested and compared to a set of samples left in the laboratory also under refrigerated conditions (group control). All measurements were conducted using two Sysmex XT-2000i analyzers. Haemoglobin concentration, reticulocytes percentage, and OFF-score numerical data were the same for samples analyzed just after collection and after a shipment under refrigerated conditions up to 72 h. Detailed information reported especially by the differential (DIFF) channel scatterplot of the Sysmex XT-2000i indicated that there were signs of blood deterioration, but were not of relevance for the variables used in the Athlete Biological Passport. As long as the cold chain is guaranteed, the time delay between the collection and the analyses of blood variables can be extended. Copyright© 2015 John Wiley & Sons, Ltd.
Resumo:
El domini de la llengua escolar apareix en totes les polítiques educatives com el tema central a través del qual s’ha d’incidir per garantir la igualtat i la cohesió social, ja que l’èxit escolar passa per desenvolupar una bona competència en la llengua vehicular de l’ensenyament (OECD 2008). A Catalunya, tot i els esforços destinats, els resultats lingüístics de l’alumnat estranger continuen essent molt més baixos que els de l’alumnat nacional (Consell Superior d’Avaluació del Sistema Educatiu 2009). No obstant això, hi ha molt pocs estudis que hagin analitzat els factors que s’amaguen darrere dels resultats lingüístics de l’alumnat estranger. Amb aquest objectiu en ment, l’article presenta les dades d’una recerca que pretén aprofundir les variables que incideixen en el coneixement de català i castellà escrit de l’alumnat estranger escolaritzat en 57 escoles de primària repartides pel territori de Catalunya
Resumo:
L’objecte del present estudi és caracteritzar el temps de vol (Tv) de la fase aèria en l’exercici d’arrencada en halterofília. Es descriu el seu comportament en funció de l’increment progressiu de la càrrega i en relació a variables biomecàniques de l’estirada, així com la seva evolució en un cicle d’entrenament. Es va fer un test màxim de càrregues progressives amb set halterofilistes (n = 7) de competició. Mitjançant els sistemes de valoració Musclelab i Chronojump es van registrar els valors de: força (F), potència (P), velocitat (V), pic de velocitat (pV) i alçada relativa (Hrel ) de la barra en l’estirada, al costat del Tv del desplaçament dels peus de l’aixecador a l’entrada sota la barra. Es va observar una moderada correlació negativa (r = –0,561; p < 0,01) entre el Tv i la càrrega màxima del test (%1RMT). No es van trobar correlacions significatives per al Tv respecte a la resta de variables analitzades. El Tv disminuïa amb l’increment de la càrrega en rangs submàxims, i era de natura aleatòria amb l’ocupació de càrregues màximes. En un subgrup de la mostra (n = 4) es van valorar les mateixes variables passades vuit setmanes. El Tv, la Pmàx i el pV suggereixen ser variables suficientment sensibles per monitoritzar els canvis generats per l’entrenament en vuit setmanes, encara que la reduïda dimensió mostral no va permetre aconseguir diferències significatives. Aquests resultats destaquen la possibilitat de considerar el Tv i la P com a mesures de control en l’entrenament d’halterofilistes, preferentment en l’ús de càrregues submàximes.
Resumo:
Durante las últimas décadas se ha producido un creciente interés en nuestro país en relación a las economías regionales dada la necesidad de los gobiernos regionales de obtener información sobre sus economías para así llevar a cabo actuaciones de política económica más efectivas y eficientes. En este marco, los modelos econométricos constituyen una herramienta de utilidad puesto que ofrecen información sobre las relaciones estructurales que se dan en una economía y permiten predecir su evolución. Sin embargo, la utilización de dichos modelos con finalidad predictiva se enfrenta al inconveniente de la elevada inestabilidad a corto plazo que se produce en las relaciones entre variables económicas a nivel regional. Por este motivo, en el presente trabajo se propone la utilización de un modelo de coeficientes variables para recoger dicha inestabilidad y mejorar las predicciones sobre la evolución de las variables del bloque de producción de la economía catalana. Para contrastar la mejora obtenida a partir de la aplicación de dicho modelo, se compara su capacidad predictiva con la de un modelo de coeficientes fijos. Los resultados muestran un mejor comportamiento del modelo de coeficientes variables frente al modelo de coeficientes fijos.