881 resultados para control over life


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Objective: To examine changes in smoking behaviour among young women over four life stages: leaving home; employment or attending college or university; marriage; and parenthood. Methods: Young women participating in the Australian Longitudinal Study on Women's Health completed postal questionnaires in 1996 and 2000. Results: Unmarried women who moved out of their parents' home between 1996 and 2000 had higher odds of adopting smoking than those who had not lived with their parents at either time (OR 1.8, 95% Cl 1.2-2.6). Married women had lower odds of resuming smoking after quitting (OR 0.4, 95% Cl 0.2-0.7) than unmarried women. Women who were pregnant in 2000 had higher odds of quitting smoking (OR 3.8, 95% Cl 2.5-5.6) and women who were pregnant in 1996 and not in 2000 had higher odds of starting to smoke again (OR 3.2, 95% Cl 1.6-6.2) than women who were not pregnant. The odds of being a current smoker or adopting smoking were significantly greater for women who binge drank alcohol or used cannabis and other illicit drugs. Conclusions: Adoption, maintenance and cessation of smoking among young women is strongly related to major life stage transitions, illicit drug use and alcohol consumption. Implications: Life changes such as marriage and actual or contemplated pregnancy provide opportunities for targeted interventions to help women quit smoking and not relapse after having a baby. Legislation to control smoking on licensed premises would reduce the social pressure on women to smoke.

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Eight new vesicle-forming dimeric surfactants are synthesized: the polar headgroup separation in such dimeric amphiphiles strongly influences their vesicular thermotropic phase-transition behaviour.

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A novel series of vesicle-forming ion-paired amphiphiles, bis(hexadecyldimethylammonium)alkane dipalmitate (1a-1h), containing four chains were synthesized with two isolated headgroups. In each of these amphiphiles, the two headgroup charges are separated by a flexible polymethylene spacer chain -[(CH2)(m)]- of varying lengths (m) such that the length and the conformation of the spacer chain determine the intra-"monomer" headgroup separation. Transmission electron microscopy indicated that each of these forms bilayer membranes upon dispersion in aqueous media. The vesicular properties of these aggregates have been examined by differential scanning calorimetry and temperature-dependent fluorescence anisotropy measurements. Interestingly, their T-m values decreased with the increase in the m value. Thus while the apparent T-m of the lipid with m = 2 (1a) is 74.1 degrees C, the corresponding value observed for the lipid with m = 12 (1h) is 38.9 degrees C. The fluorescence anisotropy values (r) for 1b-1g were quite high (r similar to 0.3) compared to that of 1h (r similar to 0.23) at 20-30 degrees C in their gel states. On the other hand, the r value for vesicular 1b beyond melting was higher (0.1) compared to any of those for 1c-1h (similar to 0.04-0.06). X-ray diffraction of the cast films was performed to understand the nature and the thickness of these membrane organizations. The membrane widths ranged from 30 to 51 A as the m values varied. The entrapment of a small water-soluble solute, riboflavin, by the individual vesicular aggregates, and their sustenance: under an imposed transmembrane pH gradient have also been examined. These results show that all lipid vesicles entrap riboflavin and that generally the resistance to OH- permeation decreases with the increase in m value. Finally,all the above observations were comparatively analyzed, and on the basis of the calculated structures of these lipids, it was possible to conclude that membrane propel-ties can be modulated by spacer chain length variation of the ion-paired amphiphiles.

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Facile synthesis of two new dimesitylboryl appended BODIPYs is reported. The two dyads have similar fluorescent chromophores but differ in their molecular conformations. They exhibit dual fluorescence, intramolecular energy transfer between boryl and BODIPY chromophores and different fluorescence responses (emission enhancement and quenching) upon fluoride binding.

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© 2015 IEEE.We consider a wireless control architecture with multiple control loops over a shared wireless medium. A scheduler observes the random channel conditions that each control system experiences over the shared medium and opportunistically selects systems to transmit at a set of non-overlapping frequencies. The transmit power of each system also adapts to channel conditions and determines the probability of successfully receiving and closing the loop. We formulate the optimal design of channel-aware scheduling and power allocation that minimize the total power consumption while meeting control performance requirements for all systems. In particular, it is required that for each control system a given Lyapunov function decreases at a specified rate in expectation over the random channel conditions. We develop an offline algorithm to find the optimal communication design, as well as an online protocol which selects scheduling and power variables based on a random observed channel sequence and converges almost surely to the optimal operating point. Simulations illustrate the power savings of our approach compared to other non-channel-aware schemes.

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Objectives: To explore the associations of working hours ( paid, domestic, commuting, and total) with sickness absence, and to examine whether these associations vary according to the level of employee control over daily working hours.

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HSDPA specifications include support for a flexible framework for QoS management. In this paper, it is shown how buffer management could be incorporated into HSDPA QoS framework for 'multimedia' traffic QoS control in the MAC-hs of the Node-B. A time-space-priority (TSP) scheme is proposed as viable buffer management scheme to this effect. Comparative simulation study with other schemes is presented, demonstrating the effectiveness of the TSP buffer management scheme for 'multimedia' service QoS control in HSDPA Node-B data buffers

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Beyond Criminal Justice presents a vision of a future without brutal, authoritarian and repressive penal regimes. Many of the papers brought together here have been unavailable for more than two decades. Their republication indicates not only their continuing theoretical importance to abolitionist studies but also how they provide important insights into the nature and legitimacy of criminal processes in the here and now. Contributors highlight the human consequences of the harms of imprisonment, evidencing the hurt, injury and damage of penal incarceration across a number of different countries in Europe. Focusing on penal power and prisoner contestation to such power, the moral and political crises of imprisonment are laid bare. The contributors to Beyond Criminal Justice explore the urgent need for a coherent, rational and morally and politically sophisticated theoretical basis for penal abolitionism. Advocating a utopian imagination and at the same time practical solutions already implemented in countries around Europe - alongside grappling with controversial debates such as abolitionist responses to rape and sexual violence - the book steps outside of common sense assumptions regarding 'crime', punishment and 'criminal justice'. Beyond Criminal Justice will be of interest to students of criminology, zemiology, sociology, penology and critical legal studies as well as anyone interested in rethinking the problem of 'crime' and challenging the logic of the penal rationale.

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Decades of research attest that memory processes suffer under conditions of auditory distraction. What is however less well understood is whether people are able to modify how their memory processes are deployed in order to compensate for disruptive effects of distraction. The metacognitive approach to memory describes a variety of ways people can exert control over their cognitive processes to optimize performance. Here we describe our recent investigations into how these control processes change under conditions of auditory distraction. We specifically looked at control of encoding in the form of decisions about how long to study a word when it is presented and control of memory reporting in the form of decisions whether to volunteer or withhold retrieved details. Regarding control of encoding, we expected that people would compensate for disruptive effects of distraction by extending study time under noise. Our results revealed, however, that when exposed to irrelevant speech, people curtail rather than extend study. Regarding control of memory reporting, we expected that people would compensate for the loss of access to memory records by volunteering responses held with lower confidence. Our results revealed, however, that people’s reporting strategies do not differ when memory task is performed in silence or under auditory distraction, although distraction seriously undermines people’s confidence in their own responses. Together, our studies reveal novel avenues for investigating the psychological effects of auditory distraction within a metacognitive framework.

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Anxiolytic effects of perceived control have been observed across species. In humans, neuroimaging studies have suggested that perceived control and cognitive reappraisal reduce negative affect through similar mechanisms. An important limitation of extant neuroimaging studies of perceived control in terms of directly testing this hypothesis, however, is the use of within-subject designs, which confound participants' affective response to controllable and uncontrollable stress. To compare neural and affective responses when participants were exposed to either uncontrollable or controllable stress, two groups of participants received an identical series of stressors (thermal pain stimuli). One group ("controllable") was led to believe they had behavioral control over the pain stimuli, whereas another ("uncontrollable") believed they had no control. Controllable pain was associated with decreased state anxiety, decreased activation in amygdala, and increased activation in nucleus accumbens. In participants who perceived control over the pain, reduced state anxiety was associated with increased functional connectivity between each of these regions and ventral lateral/ventral medial pFC. The location of pFC findings is consistent with regions found to be critical for the anxiolytic effects of perceived control in rodents. Furthermore, interactions observed between pFC and both amygdala and nucleus accumbens are remarkably similar to neural mechanisms of emotion regulation through reappraisal in humans. These results suggest that perceived control reduces negative affect through a general mechanism involved in the cognitive regulation of emotion.