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The effect of Internet use on social relationships is still a matter of intense debate. This study examined the relationships between use of social media (instant messaging and social network sites), network size, and emotional closeness in a sample of 117 individuals aged 18 to 63 years old. Time spent using social media was associated with a larger number of online social network "friends." However, time spent using social media was not associated with larger offline networks, or feeling emotionally closer to offline network members. Further, those that used social media, as compared to non-users of social media, did not have larger offline networks, and were not emotionally closer to offline network members. These results highlight the importance of considering potential time and cognitive constraints on offline social networks when examining the impact of social media use on social relationships. 相似文献
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The purpose of this study was to investigate the perceptions of African American male counselor educators regarding the limited number of African American male faculty members in counselor education. Implications and suggestions on how universities can recruit and retain African American male faculty members are provided. El propósito de este estudio fue investigar las percepciones de educadores en consejería afroamericanos con respecto al limitado número de miembros afroamericanos entre el profesorado para la educación de consejeros. Se proporcionan implicaciones y sugerencias sobre cómo las universidades pueden contratar y retener profesores varones afroamericanos. 相似文献
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Preservation of long-term memory and synaptic plasticity despite short-term impairments in the Tc1 mouse model of Down syndrome 下载免费PDF全文
Morice E Andreae LC Cooke SF Vanes L Fisher EM Tybulewicz VL Bliss TV 《Learning & memory (Cold Spring Harbor, N.Y.)》2008,15(7):492-500
Down syndrome (DS) is a genetic disorder arising from the presence of a third copy of the human chromosome 21 (Hsa21). Recently, O’Doherty and colleagues in an earlier study generated a new genetic mouse model of DS (Tc1) that carries an almost complete Hsa21. Since DS is the most common genetic cause of mental retardation, we have undertaken a detailed analysis of cognitive function and synaptic plasticity in Tc1 mice. Here we show that Tc1 mice have impaired spatial working memory (WM) but spared long-term spatial reference memory (RM) in the Morris watermaze. Similarly, Tc1 mice are selectively impaired in short-term memory (STM) but have intact long-term memory (LTM) in the novel object recognition task. The pattern of impaired STM and normal LTM is paralleled by a corresponding phenotype in long-term potentiation (LTP). Freely-moving Tc1 mice exhibit reduced LTP 1 h after induction but normal maintenance over days in the dentate gyrus of the hippocampal formation. Biochemical analysis revealed a reduction in membrane surface expression of the AMPAR (α-amino-3-hydroxy-5-methyl-4-propionic acid receptor) subunit GluR1 in the hippocampus of Tc1 mice, suggesting a potential mechanism for the impairment in early LTP. Our observations also provide further evidence that STM and LTM for hippocampus-dependent tasks are subserved by parallel processing streams. 相似文献
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Recent commentaries by Verheijde et al, Evans and Potts suggesting that donation after cardiac death practices routinely violate
the dead donor rule are based on flawed presumptions. Cell biology, cardiopulmonary resuscitation, critical care life support
technologies, donation and transplantation continue to inform concepts of life and death. The impact of oxygen deprivation
to cells, organs and the brain is discussed in relation to death as a biological transition. In the face of advancing organ
support and replacement technologies, the reversibility of cardiac arrest is now purely related to the context in which it
occurs, in association to the availability and application of support systems to maintain oxygenated circulation. The 'complete
and irreversible' lexicon commonly used in death discussions and legal statutes are ambiguous, indefinable and should be replaced
by accurate terms. Criticism of controlled DCD on the basis of violating the dead donor rule, where autoresuscitation has
not been described beyond 2 minutes, in which life support is withdrawn and CPR is not provided, is not valid. However, any
post mortem intervention that re-establishes brain blood flow should be prohibited. In comparison to traditional practice,
organ donation has forced the clarification of the diagnostic criteria for death and improved the rigour of the determinations. 相似文献
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Revisiting the Stanford prison experiment: could participant self-selection have led to the cruelty?
The authors investigated whether students who selectively volunteer for a study of prison life possess dispositions associated with behaving abusively. Students were recruited for a psychological study of prison life using a virtually identical newspaper ad as used in the Stanford Prison Experiment (SPE; Haney, Banks & Zimbardo, 1973) or for a psychological study, an identical ad minus the words of prison life. Volunteers for the prison study scored significantly higher on measures of the abuse-related dispositions of aggressiveness, authoritarianism, Machiavellianism, narcissism, and social dominance and lower on empathy and altruism, two qualities inversely related to aggressive abuse. Although implications for the SPE remain a matter of conjecture, an interpretation in terms of person-situation interactionism rather than a strict situationist account is indicated by these findings. Implications for interpreting the abusiveness of American military guards at Abu Ghraib Prison also are discussed. 相似文献
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Past research has found conservative Protestants to be less willing than most Americans to grant civil liberties to unpopular groups. In light of evidence of high and growing civility by Smith (2000) and Hunter (1984), there is good reason to believe that conservative Protestants are becoming less distinctive with regard to granting civil freedoms. We update and expand previous research on conservative Protestants and civil liberties by examining the civil liberties measures in the General Social Survey over a 26-year period, with special attention to explaining conservative Protestantism's rejection of civil liberties. In comparison to mainline Protestants and Catholics, we find that conservative Protestants are still less willing to grant civil liberties to unpopular groups, though important qualifications apply. Various explanations are examined. 相似文献
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It is a common criticism of presentism – the view according to which only the present exists – that it errs against truthmaker theory. Recent attempts to resolve the truthmaker objection against presentism proceed by restricting truthmaker maximalism (the view that all truths have truthmakers), maintaining that propositions concerning the past are not made true by anything, but are true nonetheless. Support for this view is typically garnered from the case for negative existential propositions, which some philosophers contend are exceptions to truthmaker maximalism. In this article, we argue that a ‘no truthmakers’ approach to the truthmaker objection is critically flawed. 相似文献