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21.
    
This study examined whether bullies, victims, bully–victims (who are both bullies and victims), and students who reported no or low levels of bullying and victimization differed in their levels of social and emotional skills. Data were collected from 623 children in fifth and sixth grades from four Egyptian elementary schools; their ages ranged from 10 to 12 years. K‐means cluster analysis revealed four groups: bullies (n = 138), victims (n = 178), bully–victims (n = 59), and children who were not involved in bullying behaviour (n = 248). Data were analyzed using multinomial logistic regression. The findings indicated that boys were more involved in bullying behaviour than girls, and both bullies and bully–victims were less likely to adhere to social rules and politeness than children who were not involved in bullying. Both bullies and victims were less aware of the physiological reactions of their emotions than uninvolved children, and were less able to apply social rules in social interaction. Both victims and bully–victims reported less likeability than children not involved in bullying. Verbal sharing, attending to others’ emotions, and analysis of emotions did not have a statistically significant relationship with the probabilities of classifying children to any bullying group versus children not involved in bullying. Social skills were more important than emotional awareness in predicting the likelihood of classifying children in one of the three bullying groups versus children who not involved in bullying. The main conclusion is that social and emotional skills together may provide an effective means of intervention for bullying problems.  相似文献   
22.
The length of the stagnant stage during the new ferrite growth starting from a mixture of austenite and ferrite has been investigated for a Fe-0.17Mn-0.023C (wt%) alloy. It was found that the stagnant stage depends on the thermal path followed to create the mixture, and deduce that the tie-lines for austenite to ferrite transformation are quite different from those for ferrite to austenite transformation. The length of the stagnant stage is determined by the very local partitioning effect at the interface, and it can be used as a tool to monitor the Mn partitioning.  相似文献   
23.
    
The work-hardening behaviour of virgin martensitic steel has been investigated in a strictly un-aged state and after various ageing conditions. At room temperature (RT), the un-aged alloy shows astonishing tensile performances (ultimate tensile stress?=?1600?MPa/uniform elongation?=?15%) but unexpected serrations. These serrations can be suppressed by static ageing (at RT or higher) while maintaining the initial work-hardening rate (ageing at RT). Parallel investigations using atom probe tomography reveal that the distribution of carbon at the atomic scale evolves from purely homogeneous for virgin martensite to partly segregated at a very fine scale (5–10?nm) after static ageing. This particular mechanical behaviour can therefore be associated with a very local decrease in available carbon in solid solution due to redistribution and segregations on defects (nanotwins) that occurs rapidly, even after few days at RT.  相似文献   
24.
    
The essential activity of a manager is decision making, which is becoming more and more complex, mainly in the multi‐criteria problems. Multi‐choice goal programming (MCGP) is considered as a robust tool in operational research to solve this type of problem. However, in real world problems, determining precise targets for the goals is a difficult task. To deal with such situation, Tabrizi introduced and used in 2012 the concept of membership functions in the MCGP model in order to model the targets fuzziness of each goal. In their model, they considered just only one type of functions (triangular form), which does not reflect adequately the decision maker's preferences that are considered as an essential element for modelling the goal's fuzziness. Their model is called Fuzzy MCGP. In this paper, new ideas are presented to reformulate MCGP model to tackle all types of functions by introducing the (decision maker's) preferences. The concept of indifference thresholds is used in the new formulation for characterizing the imprecision and the preferences associated with all types of the goals. The proposed formulation provides useful insight about the solution of a new class of problems. A numerical example is given to demonstrate the validity and strength of the new formulation. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
25.
The current study investigated the effects of combat exposure, childhood trauma, and depression on posttraumatic stress disorder (PTSD) severity. Participants were 299 male veterans from the Korean War, World War II, Vietnam, and the first Gulf War who were being screened for admission to the PTSD unit. Participants were assessed with the Clinician-Administered PTSD Scale (CAPS), Combat Exposure Scale (CES), Hamilton Depression Rating Scale (HAMD), Childhood Trauma Questionnaire (CTQ), and Mississippi Scale for PTSD (MPTSD). Results of multiple regression analyses indicated that, as expected, combat exposure and depression were significant predictors of PTSD severity. When examined with combat exposure, childhood trauma has a complex relationship to PTSD severity. Examination of the interaction between the CES and CTQ suggests that when levels of combat are low and childhood trauma levels are high, the CTQ is related to higher levels of PTSD severity on the CAPS, regardless of depression. Treatment implications are discussed.  相似文献   
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27.
This study examined moderating effects of age on longitudinal associations among quality of life (QOL) and its demographic (e.g., age), clinical [e.g., prostate-specific antigen (PSA) level], and affective and cognitive predictors (i.e., distress, worries about recurrence, decisional regret, subjective life expectancy) in prostate cancer patients treated with external beam radiation (N = 391). Demographic and clinical characteristics were assessed at diagnosis, affective and cognitive variables at 6 months after diagnosis, and QOL at 12 months after diagnosis. Multiple-group analyses showed that among younger patients (< or =68 years old, n = 199), lower levels of decisional regret were associated with better functional QOL, and lower Gleason scores and PSA levels were associated with lower levels of distress and longer expected survival time, respectively. Being employed was related to higher levels of functional QOL and frequent worries about recurrence. Among older patients (>68 years old, n = 192), lower levels of distress were associated with higher levels of functional QOL, and longer expected survival time was associated with better functional and physical QOL.  相似文献   
28.
Organ donation after cessation of circulation and respiration, both controlled and uncontrolled, has been proposed by the Institute of Medicine as a way to increase opportunities for organ procurement. Despite claims to the contrary, both forms of controlled and uncontrolled donation after cardiac death raise significant ethical and legal issues. Identified causes for concern include absence of agreement on criteria for the declaration of death, nonexistence of universal guidelines for duration before stopping resuscitation efforts and techniques, and assumption of presumed intent to donate for the purpose of initiating temporary organ-preservation interventions when no expressed consent to donate is present. From a legal point of view, not having scientifically valid criteria of cessation of circulation and respiration for declaring death could lead to a conclusion that organ procurement itself is the proximate cause of death. Although the revised Uniform Anatomical Gift Act of 2006 provides broad immunity to those involved in organ-procurement activities, courts have yet to provide an opinion on whether persons can be held liable for injuries arising from the determination of death itself. Preserving organs in uncontrolled donation after cardiac death requires the administration of life-support systems such as extracorporeal membrane oxygenation. These life-support systems can lead to return of signs of life that, in turn, have to be deliberately suppressed by the administration of pharmacological agents. Finally, allowing temporary organ-preservation interventions without expressed consent is inherently a violation of the principle of respect for a person's autonomy. Proponents of organ donation from uncontrolled donation after cardiac death, on the other hand, claim that these nonconsensual interventions enhance respect for autonomy by allowing people, through surrogate decision making, to execute their right to donate organs. However, the lack of transparency and the absence of protection of individual autonomy, for the sake of maximizing procurement opportunities, have placed the current organ-donation system of opting-in in great jeopardy. Equally as important, current policies enabling and enhancing organ procurement practices, pose challenges to the constitutional rights of individuals in a pluralistic society as these policies are founded on flawed medical standards for declaring death.  相似文献   
29.
The present study investigated the effects of a treatment program on the self-injurious behaviors of a 12-year-old autistic male. Initial observations indicated that these behaviors functioned primarily as escape responses to terminate performance demands. For 1 year the subject received general compliance training with the frequency of demands being systematically increased through consecutive treatment weeks. The subject's self-injurious behaviors were no longer reinforced by his escaping from demands nor did they receive social attention. Compliance to demands and appropriate behaviors in general were positively reinforced. The treatment produced substantial reductions in the rates of self-injurious behaviors and increased compliance. Additionally, the intensity of the subject's self-injurious behaviors decreased over the course of treatment. The present study suggests that the treatment approach is a reliable means of not only reducing self-injurious behaviors but also expanding performance repertoires.  相似文献   
30.
For first order languages with no individual constants, empty structures and truth values (for sentences) in them are defined. The first order theories of the empty structures and of all structures (the empty ones included) are axiomatized with modus ponens as the only rule of inference. Compactness is proved and decidability is discussed. Furthermore, some well known theorems of model theory are reconsidered under this new situation. Finally, a word is said on other approaches to the whole problem.  相似文献   
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