29 research outputs found
Recommended from our members
Target revaluation after failed takeover attempts - cash versus stock
Cash- and stock-financed takeover bids induce strikingly different target revaluations. We exploit detailed data on unsuccessful takeover bids between 1980 and 2008, and we show that targets of cash offers are revalued on average by +15% after deal failure, whereas stock targets return to their pre-announcement levels. The differences in revaluation do not revert over longer horizons. We find no evidence that future takeover activities or operational changes explain these differences. While the targets of failed cash and stock offers are both more likely to be acquired over the following eight years than matched control firms, no differences exist between cash and stock targets, neither in the timing nor in the value of future offers. Similarly, we cannot detect differential operational policies following the failed bid. Our results are most consistent with cash bids revealing prior undervaluation of the target. We reconcile our findings with the opposite conclusion in earlier literature (Bradley, Desai, and Kim, 1983) by identifying a look-ahead bias built into their sample construction
Evaluating the drivers of and obstacles to the willingness to use cognitive enhancement drugs: the influence of drug characteristics, social environment, and personal characteristics
Sattler S, Mehlkop G, Graeff P, Sauer C. Evaluating the drivers of and obstacles to the willingness to use cognitive enhancement drugs: the influence of drug characteristics, social environment, and personal characteristics. Substance Abuse Treatment, Prevention, and Policy. 2014;9(1): 8.Background
The use of cognitive enhancement (CE) by means of pharmaceutical agents has been the subject of intense debate both among scientists and in the media. This study investigates several drivers of and obstacles to the willingness to use prescription drugs non-medically for augmenting brain capacity.
Methods
We conducted a web-based study among 2,877 students from randomly selected disciplines at German universities. Using a factorial survey, respondents expressed their willingness to take various hypothetical CE-drugs; the drugs were described by five experimentally varied characteristics and the social environment by three varied characteristics. Personal characteristics and demographic controls were also measured.
Results
We found that 65.3% of the respondents staunchly refused to use CE-drugs. The results of a multivariate negative binomial regression indicated that respondents’ willingness to use CE-drugs increased if the potential drugs promised a significant augmentation of mental capacity and a high probability of achieving this augmentation. Willingness decreased when there was a high probability of side effects and a high price. Prevalent CE-drug use among peers increased willingness, whereas a social environment that strongly disapproved of these drugs decreased it. Regarding the respondents’ characteristics, pronounced academic procrastination, high cognitive test anxiety, low intrinsic motivation, low internalization of social norms against CE-drug use, and past experiences with CE-drugs increased willingness. The potential severity of side effects, social recommendations about using CE-drugs, risk preferences, and competencies had no measured effects upon willingness.
Conclusions
These findings contribute to understanding factors that influence the willingness to use CE-drugs. They support the assumption of instrumental drug use and may contribute to the development of prevention, policy, and educational strategies
Association of innate immune single-nucleotide polymorphisms with the electroencephalogram during desflurane general anaesthesia
Published online: 19 December 2013The electroencephalogram (EEG) records the electrical activity of the brain and enables effects of anaesthetic drugs on brain functioning to be monitored. Identification of genes contributing to EEG variability during anaesthesia is important to the clinical application of anaesthesia monitoring and may provide an avenue to identify molecular mechanisms underlying the generation and regulation of brain oscillations. Central immune signalling can impact neuronal activity in the brain and accumulating evidence suggests an important role for cytokines as neuronal modulators. We tested 21 single-nucleotide polymorphisms (SNPs) in immune-related genes for associations with three anaesthesia-induced EEG patterns; spindle amplitude, delta power and alpha power, during general anaesthesia with desflurane in 111 patients undergoing general, gynaecological or orthopaedic surgery. Wide inter-patient variability was observed for all EEG variables. MYD88 rs6853 (p = 6.7 × 10−4) and IL-1β rs1143627 in conjunction with rs6853 (p = 1.5 × 10−3) were associated with spindle amplitude, and IL-10 rs1800896 was associated with delta power (p = 1.3 × 10−2) suggesting involvement of cytokine signalling in modulation of EEG patterns during desflurane anaesthesia. BDNF rs6265 was associated with alpha power (p = 3.9 × 10−3), suggesting differences in neuronal plasticity might also influence EEG patterns during desflurane anaesthesia. This is the first study we are aware of that has investigated genetic polymorphisms that may influence the EEG during general anaesthesia.Claire Vignette Mulholland, Andrew Alexander Somogyi, Daniel Thomas Barratt, Janet Kristie Coller, Mark Rowland Hutchinson, Gregory Michael Jacobson, Raymond Thomas Cursons and James Wallace Sleig
Sleep Health: Reciprocal Regulation of Sleep and Innate Immunity
Sleep disturbances including insomnia independently contribute to risk of inflammatory disorders and major depressive disorder. This review and overview provides an integrated understanding of the reciprocal relationships between sleep and the innate immune system and considers the role of sleep in the nocturnal regulation of the inflammatory biology dynamics; the impact of insomnia complaints, extremes of sleep duration, and experimental sleep deprivation on genomic, cellular, and systemic markers of inflammation; and the influence of sleep complaints and insomnia on inflammaging and molecular processes of cellular aging. Clinical implications of this research include discussion of the contribution of sleep disturbance to depression and especially inflammation-related depressive symptoms. Reciprocal action of inflammatory mediators on the homeostatic regulation of sleep continuity and sleep macrostructure, and the potential of interventions that target insomnia to reverse inflammation, are also reviewed. Together, interactions between sleep and inflammatory biology mechanisms underscore the implications of sleep disturbance for inflammatory disease risk, and provide a map to guide the development of treatments that modulate inflammation, improve sleep, and promote sleep health