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91.
We consider Facebook unfriending as a form of relationship termination with negative emotional and cognitive consequences. Specifically, ruminative and negative emotional responses are examined via an online survey of adult Facebook users who were unfriended. These responses were positively related to each other and to Facebook intensity. Rumination was positively predicted by using Facebook to connect with existing contacts and was more likely when the unfriender was a close partner. Participants also responded with greater rumination and negative emotion when they knew who unfriended them, when they thought they were unfriended for Facebook-related reasons, and when participants initiated the Facebook friend request. The contribution of these exploratory findings to our growing understanding of negative relational behaviors on Facebook are discussed.  相似文献   
92.
Electronic aggression, or cyberbullying, is a relatively new phenomenon. As such, consistency in how the construct is defined and operationalized has not yet been achieved, inhibiting a thorough understanding of the construct and how it relates to developmental outcomes. In a series of two studies, exploratory and confirmatory factor analyses (EFAs and CFAs respectively) were used to examine whether electronic aggression can be measured using items similar to that used for measuring traditional bullying, and whether adolescents respond to questions about electronic aggression in the same way they do for traditional bullying. For Study I (n = 17 551; 49% female), adolescents in grades 8-12 were asked to what extent they had experience with physical, verbal, social, and cyberbullying as a bully and victim. EFA and CFA results revealed that adolescents distinguished between the roles they play (bully, victim) in a bullying situation but not forms of bullying (physical, verbal, social, cyber). To examine this further, Study II (n = 733; 62% female), asked adolescents between the ages of 11 and 18 to respond to questions about their experience sending (bully), receiving (victim), and/or seeing (witness) specific online aggressive acts. EFA and CFA results revealed that adolescents did not differentiate between bullies, victims, and witnesses; rather, they made distinctions among the methods used for the aggressive act (i.e. sending mean messages or posting embarrassing pictures). In general, it appears that adolescents differentiated themselves as individuals who participated in specific mode of online aggression, rather than as individuals who played a particular role in online aggression. This distinction is discussed in terms of policy and educational implications.  相似文献   
93.
Cyberbullying, or online aggression, is an issue of increasing concern, however little research has been conducted on the motivations underlying this form of aggression. Using a mixed-method approach, by means of survey and interview data, we explored whether online aggressive acts were motivated by proactive (intentionally aggressing to obtain a resource or a goal), and/or reactive (aggression that occurs in reaction to provocation) reasons. Participants for the survey portion of the study included 733 adolescents between the ages of 10 and 18, while a subset of 15 adolescents participated in semi-structured interviews. Factor analysis revealed that, in contrast to traditional forms of bullying, adolescents do not identify themselves according to the role they played in an internet aggressive situation (i.e. bully, victim, witness), but according to the method of aggression they used (i.e. sending mean messages, posting embarrassing photos, and developing hostile websites). More interestingly, regression analyses demonstrated that motivations for aggressing online also varied according to method of aggression rather than role. For example, adolescents who chose to aggress by posting mean messages or posting embarrassing photos were more likely to do so for reactive reasons, while adolescents who spent time creating hostile websites did so for proactive reasons.  相似文献   
94.
This study used objectification theory (B. L. Fredrickson & T.-A. Roberts, 1997) to predict that the media's insidious practice of objectifying bodies socializes individuals to take an outsider's perspective on the physical self (i.e., self-objectify) and to habitually monitor their appearance (i.e., engage in body surveillance). To test these hypotheses, a 2-year panel study using an undergraduate sample was conducted. Cross-lagged path models showed that exposure to sexually objectifying television measured during Year 1 increased trait self-objectification (trait SO) during Year 2 for both women and men. At the same time, trait SO during Year 1 decreased exposure to sexually objectifying television during Year 2, suggesting that both male and female participants selectively avoided sexually objectifying television based on antecedent trait SO. Moreover, exposure to sexually objectifying television and magazines increased body surveillance for men only. The discussion focuses on the process by which the media create body-focused perceptions.  相似文献   
95.
The high explosive (HE) compounds royal demolition explosive or hexahydro-1,3,5-trinitro-1,3,5-triazocine (RDX) and high melting explosive or octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) have been detected as groundwater contaminants at many military facilities. This research evaluated adsorption of RDX and HMX with granular activated carbon (GAC) to provide guidance for the design and operation of GAC adsorbers for treatment of HE-contaminated groundwater. Five GACs were screened using rapid small-scale column tests (RSSCTs), after which additional tests were performed with the two GACs that most effectively treated mixtures of RDX and HMX (Calgon F400 and Northwestern LB-830). GAC service life as a function of empty-bed contact time (EBCT) was determined using RSSCTs for a range of simulated full scale EBCTs with influent concentrations of 2,200 μg RDX/L and 350 μg HMX/L. Increasing the influent concentration of either contaminant significantly reduced the predicted service life, as did preloading GAC with groundwater natural organic matter. In batch isotherm tests, RDX was less adsorbable than HMX under all conditions studied. Concurrent loading of natural organic matter reduced the Freundlich K for RDX, whereas adsorption of HMX was not affected. Of the GACs tested, Calgon F400 most effectively removed RDX and HMX.  相似文献   
96.
The authors explored the effect of Parkinson's disease (PD) on the generation and maintenance of response readiness in a simple reaction time task. They compared performance of idiopathic PD patients without dementia, age-matched controls, and younger controls over short (1-, 3-, and 6-s) and long (12- and 18-s) foreperiod intervals. After each trial, the authors probed memory for visual information that also had to be maintained during the trial interval. Patients and controls did not differ overall in their ability to maintain readiness over long delays. However, within the PD group only, errors in maintaining visual information were correlated with difficulty in maintaining readiness, suggesting that systems impaired in PD may facilitate the maintenance of processing in both motor and cognitive domains. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
97.
The increasing need for hybrid Knowledge-Based Systems (KBS) that accommodate more complex applications has led to the need for new verification concerns that are more specific to the hybrid representation using objects and rule-based inference. Traditionally, verification of expert systems has focused solely on rule-based inference systems. Hybrid KBSs present additional verification problems not found in traditional rule-based systems. This paper is an investigation into the anomalies that may be present in a hybrid representation that warrant detection for the verification of the KBS. Many anomalies are due to the interaction of the component parts of the hybrid KBS. For example, subsumption anomalies arise due to an interaction between inheritance of objects and rule-based inference. In this paper, we extend the context of subsumption anomalies and introduce additional types of anomalies that may be present in the KBS. The goal of this research is to make hybrid KBSs more reliable by detecting such anomalies.  相似文献   
98.
This study explored the moderating effects of children's neighborhoods on the link between hostile parenting and externalizing behavior. Participants were 1st- or 2nd-grade children in an urban northeastern community. Children were administered the Parenting and Neighborhood scales of the Child Puppet Interview, and mothers completed questionnaires on neighborhood quality and parenting practices. Census tract measures of neighborhood quality and teachers' reports of children's externalizing behavior also were obtained. Results indicated that children's and mothers' perceptions of neighborhood involvement-cohesion buffered the link between hostile parenting and externalizing problems. Children's externalizing behavior was unrelated to census tract variables. Findings highlight the protective effect of neighborhood social cohesion and the utility of including young children's perspectives in research on neighborhoods and families. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
99.
Biofiltration, a process in which contaminated air is passed through a biologically active bed, can be used to remove volatile organic pollutants from air streams. While most biofilters rely on bacteria to degrade organic pollutants, biofilters utilizing a fungal biofilm have the potential to be an efficient and robust treatment alternative. In this study, two surfactants were evaluated for their ability to activate the spores of the fungus Exophiala lecanii-corni and reduce the start-up period typically observed in fungal vapor-phase bioreactors. Sodium dodecyl sulfate, an anionic surfactant, was found to inhibit growth of E. lecanii-corni. Polyoxyethylene sorbitan monolaurate (Tween 20), a nonionic surfactant, stimulated bud formation and enhanced toluene degradation in E. lecanii-corni cultures. Tween 20 was also found to enhance inoculum development by shortening the lag period during culture growth. However, when bioreactors were presoaked in medium containing Tween 20, washout of the fungal cells occurred during inoculation, inhibiting the initial fungal biofilm development. After a seven-day start-up period, no detrimental effects on reactor performance due to residual Tween 20 were observed, and toluene elimination capacities of up to 150?g/m3?h were achieved.  相似文献   
100.
Neurogenetic models predict neuropsychological weaknesses in the relatives of children with attention-deficit/ hyperactivity disorder (ADHD). The authors examined executive and regulatory measures in 386 relatives (307 parents, 79 siblings) of children with ADHD combined type, ADHD inattentive type, and controls. Predicted deficits were seen on trailmaking (relatives of ADHD combined type only), stop-signal reaction times (relatives of girls only), and response variability (mothers only) but not on naming or output speed. Effects generally held, even with relatives' ADHD status controlled. A neuropsychologically impaired subgroup of children with ADHD had relatives with clear neuropsychological weaknesses. The authors conclude that a neurogenetic model of ADHD etiology is supportable only for a subset of executive functions and that neuropsychological heterogeneity warrants more examination in ADHD. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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