14 resultados para Fine Structure Constant and Physical Uncertainty
em Consorci de Serveis Universitaris de Catalunya (CSUC), Spain
Resumo:
Recent improvements in the determination of the running of the fine-structure constant also allow an update of the hadronic vacuum-polarization contribution to the Lamb shift. We find a shift of -3.40(7) kHz to the 1S level of hydrogen. We also comment on the contribution of this effect to the determination by elastic electron scattering of the rms radii of nuclei.
Resumo:
This paper investigates experimentally how organisational decision processes affect the moral motivations of actors inside a firm that must forego profits to reduce harming a third party. In a "vertical" treatment, one insider unilaterally sets the harm-reduction strategy; the other can only accept or quit. In a "horizontal" treatment, the insiders decide by consensus. Our 2-by-2 design also controls for communication effects. In our data, communication makes vertical firms more ethical; voice appears to mitigate "responsibility-alleviation" in that subordinates with voice feel responsible for what their firms do. Vertical firms are then more ethical than the horizontal firms for which our bargaining data reveal a dynamic form of responsibility-alleviation and our chat data indicate a strong "insider-outsider" effect.
Resumo:
“Magic for a Pixeloscope” is a one hour show conceived to berepresented in a theater scenario that merges mixed and augmented reality (MR/AR) and full-body interaction with classical magic to create new tricks. The show was conceived by an interdisciplinary team composed by a magician, twointeraction designers, a theater director and a stage designer. Themagician uses custom based hardware and software to createnew illusions which are a starting point to explore new languagefor magical expression. In this paper we introduce a conceptualframework used to inform the design of different tricks; weexplore the design and production of some tricks included in theshow and we describe the feedback received on the world premiere and some of the conclusions obtained.
Resumo:
This paper introduces a new solution concept, a minimax regret equilibrium, which allows for the possibility that players are uncertain about the rationality and conjectures of their opponents. We provide several applications of our concept. In particular, we consider pricesetting environments and show that optimal pricing policy follows a non-degenerate distribution. The induced price dispersion is consistent with experimental and empirical observations (Baye and Morgan (2004)).
Resumo:
This paper analyses the empirical interdependences among assetreturns, real activity and inflation from a multicountry and internationalpoint of view. We find that nominal stock returns are significantly relatedto inflation only in the US, that the US term structure of interest ratespredicts both domestic and foreign inflation rates while foreign termstructures do not have this predictive power and that innovations in inflationand exchange rates induce insignificant responses of real and financialvariables. An interpretation of the dynamics and some policy implicationsof the results are provided.
Resumo:
Digital art interfaces presents cognitiveparadigms that deals with the recognition of the symbols and representations through interaction.What is presented in this paper is anapproximation of the bodily experience in that particular scenario and a new proposal which has the aim to contribute more ideas and criteria in the analysis of the learning process of aparticipant discovering an interactive space or interface. For that I propose a first new approach where metaphorically I tried to extrapolate the stages of the psychology of development stated byJean Piaget in the interface design domain.
Resumo:
It has been shown previously that the endogenous opioid system may be involved in the behavioral effects of nicotine. In the present study, the participation of endogenous enkephalins on nicotine responses has been investigated by using preproenkephalin knock-out mice. Acute nicotine-induced hypolocomotion remained unaffected in these mice. In contrast, antinociception elicited in the tail-immersion and hot-plate tests by acute nicotine administration was reduced in mutant animals. The rewarding properties of nicotine were then investigated using the place-conditioning paradigm. Nicotine induced a conditioned place preference in wild-type animals, but this effect was absent in knock-out mice. Accordingly, in vivo microdialysis studies revealed that the enhancement in dopamine extracellular levels in the nucleus accumbens induced by nicotine was also reduced in preproenkephalin-deficient mice. Finally, the somatic expression of the nicotine withdrawal syndrome precipitated in nicotine-dependent mice by mecamylamine was significantly attenuated in mutant animals. In summary, the present results indicate that endogenous opioid peptides derived from preproenkephalin are involved in the antinociceptive and rewarding properties of nicotine and participate in the expression of physical nicotine dependence.
Resumo:
Research on natural products containing hexahydropyrrolo[2,3-b]indole (HPI) has dramatically increased during the past few years. Newly discovered natural products with complex structures and important biological activities have recently been isolated and synthesized. This review summarizes the structures, biological activities, and synthetic routes for natural compounds containing HPI, emphasizing the different strategies for assembling this motif. It covers a broad gamut of molecules, from small alkaloids to complex peptides.
Resumo:
Interception requires precise estimation of time-to-contact (TTC) information. A long-standing view posits that all relevant information for extracting TTC is available in the angular variables, which result from the projection of distal objecs on to the retina. The diferent timing models rooted in this tradition have consequently relied on combining visual angle and its rate of expansion in diferent ways with tau being the most well-known solution for TTC...
Resumo:
Background: A holistic perspective on health implies giving careful consideration to the relationship between physical and mental health. In this regard the present study sought to determine the level of Positive Mental Health (PMH) among people with chronic physical health problems, and to examine the relationship between the observed levels of PMH and both physical health status and socio-demographic variables. Methods: The study was based on the Multifactor Model of Positive Mental Health (Lluch, 1999), which comprises six factors: Personal Satisfaction (F1), Prosocial Attitude (F2), Self-control (F3), Autonomy (F4), Problem-solving and Self-actualization (F5), and Interpersonal Relationship Skills (F6). The sample comprised 259 adults with chronic physical health problems who were recruited through a primary care center in the province of Barcelona (Spain). Positive mental health was assessed by means of the Positive Mental Health Questionnaire (Lluch, 1999). Results: Levels of PMH differed, either on the global scale or on specific factors, in relation to the following variables: age: global PMH scores decreased with age (r=-0.129; p=0.038); b) gender: men scored higher on F1 (t=2.203; p=0.028) and F4 (t=3.182; p=0.002), while women scored higher on F2 (t -3.086; p=0.002) and F6 (t=-2.744; p=0.007); c) number of health conditions: the fewer the number of health problems the higher the PMH score on F5 (r=-0.146; p=0.019); d) daily medication: polymedication patients had lower PMH scores, both globally and on various factors; e) use of analgesics: occasional use of painkillers was associated with higher PMH scores on F1 (t=-2.811; p=0.006). There were no significant differences in global PMH scores according to the type of chronic health condition. The only significant difference in the analysis by factors was that patients with hypertension obtained lower PMH scores on the factor Autonomy (t=2.165; p=0.032). Conclusions: Most people with chronic physical health problems have medium or high levels of PMH. The variables that adversely affect PMH are old age, polypharmacy and frequent consumption of analgesics. The type of health problem does not influence the levels of PMH. Much more extensive studies with samples without chronic pathology are now required in order to be able to draw more robust conclusions.
Resumo:
Research on natural products containing hexahydropyrrolo[2,3-b]indole (HPI) has dramatically increased during the past few years. Newly discovered natural products with complex structures and important biological activities have recently been isolated and synthesized. This review summarizes the structures, biological activities, and synthetic routes for natural compounds containing HPI, emphasizing the different strategies for assembling this motif. It covers a broad gamut of molecules, from small alkaloids to complex peptides.
Resumo:
Abstract Background: Little is known about how sitting time, alone or in combination with markers of physical activity (PA), influences mental well-being and work productivity. Given the need to develop workplace PA interventions that target employees’ health related efficiency outcomes; this study examined the associations between self-reported sitting time, PA, mental well-being and work productivity in office employees. Methods: Descriptive cross-sectional study. Spanish university office employees (n = 557) completed a survey measuring socio-demographics, total and domain specific (work and travel) self-reported sitting time, PA (International Physical Activity Questionnaire short version), mental well-being (Warwick-Edinburg Mental Well-Being Scale) and work productivity (Work Limitations Questionnaire). Multivariate linear regression analyses determined associations between the main variables adjusted for gender, age, body mass index and occupation. PA levels (low, moderate and high) were introduced into the model to examine interactive associations. Results: Higher volumes of PA were related to higher mental well-being, work productivity and spending less time sitting at work, throughout the working day and travelling during the week, including the weekends (p < 0.05). Greater levels of sitting during weekends was associated with lower mental well-being (p < 0.05). Similarly, more sitting while travelling at weekends was linked to lower work productivity (p < 0.05). In highly active employees, higher sitting times on work days and occupational sitting were associated with decreased mental well-being (p < 0.05). Higher sitting times while travelling on weekend days was also linked to lower work productivity in the highly active (p < 0.05). No significant associations were observed in low active employees. Conclusions: Employees’ PA levels exerts different influences on the associations between sitting time, mental well-being and work productivity. The specific associations and the broad sweep of evidence in the current study suggest that workplace PA strategies to improve the mental well-being and productivity of all employees should focus on reducing sitting time alongside efforts to increase PA.