2,195,113 research outputs found
Does Exposure and Receptivity to E-cigarette Advertisements Relate to E-cigarette and Conventional Cigarette Use Behaviors among Youth? Results from Wave 1 of the Population Assessment of Tobacco and Health Study
Background: E-cigarettes (EC) are the most commonly used tobacco product among youth. Additionally, youth EC users are progressing to smoking conventional cigarettes (CC). Although known to target youth, there are no current restrictions in the US on EC marketing, including advertising. The purpose of this study is to evaluate the relationship between EC advertisements and youth EC and CC use behaviors.
Methods: This study analyzed data from youth (12-17 years) aware of EC in Wave 1 (2013-2014) of the Population Assessment of Tobacco and Health (PATH) study (n=12,199). Weighted logistic regression models assessed whether exposure and receptivity to any of five randomized EC ads (two TV and three print) were associated with the outcomes of EC and CC behaviors of ever use, current (past 30 day) use, and susceptibility to future use. Additional analyses determined whether EC advertising exposure and EC and CC behaviors associations were moderated by EC advertising receptivity. All models were adjusted for sociodemographics, other combustible tobacco product use, and parent smoking.
Results: EC advertisement exposure was significantly associated to ever and current EC use as well as susceptibility to EC and CC (p
Conclusion: These findings demonstrate exposure to EC advertisements are particularly associated with EC use behaviors, but could play a role in future CC use as well. Youth who are receptive to EC advertisements appear particularly vulnerable. Further studies should focus on the role of receptivity to EC advertisements among youth in order to support regulatory policy targeting EC advertising
Temporal response to harmonic driving in electroconvection
The temporal evolution of the spatially periodic electroconvection (EC)
patterns has been studied within the period of the driving ac voltage by
monitoring the light intensity diffracted from the pattern. Measurements have
been carried out on a variety of nematic systems, including those with negative
dielectric and positive conductivity anisotropy, exhibiting "standard EC"
(s-EC), those with both anisotropies negative exhibiting "non-standard EC"
(ns-EC), as well as those with the two anisotropies positive. Theoretical
predictions have been confirmed for stationary s-EC and ns-EC patterns.
Transitions with Hopf bifurcation have also been studied. While traveling had
no effect on the temporal evolution of dielectric s-EC, traveling conductive
s-EC and ns-EC patterns exhibited a substantially altered temporal behavior
with a dependence on the Hopf frequency. It has also been shown that in
nematics with both anisotropies positive, the pattern develops and decays
within an interval much shorter than the period, even at relatively large
driving frequencies.Comment: 19 pages, 5 figure
Protecting Human Rights in the European Union: An Argument for Treaty Reform
This Note argues that the European Community ( EC ) should amend the European Community Treaty to provide authority for EC accession to the European Court of Human Rights ( ECHR ) because the belief in and protection of human rights must be at the core of a thriving constitutional legal system. As the EC continues to grow geographically, its legal competences must also grow to deal with the challenges of building a singular, unified Europe from traditionally autonomous European states and EC institutions. Part I of this Note explains the institutions of the EC, examines the principles and objectives of the ECHR and its present application in the EC, and discusses current human rights protection in the EC. Part II considers the objectives of a unified Europe, the conflicting opinions regarding EC accession to the ECHR, and the present lack of codification of human rights legislation in the EC. Part III argues that the necessity of enumerated, uniformly enforceable human rights protections at the EC level overrides claims that the EC should not extend its competences to include accession to the ECHR. This Note concludes that the EC should amend the European Community Treaty to include a provision for accession to the ECHR
Intermediate electron transport in Porphyridium: EPR studies
Measurement of photosynthetic electron transport in Porphyridium by EPR electron paramagnetic resonanc
Evaluative conditioning as a symbolic phenomenon: on the relation between evaluative conditioning, evaluative conditioning via instructions, and persuasion
Evaluative conditioning (EC) is sometimes portrayed as a primitive way of changing attitudes that is fundamentally different from persuasion via arguments. We provide a new perspective on the nature of EC and its relation to persuasion by exploring the idea that stimulus pairings can function as a symbol that conveys the nature of the relation between stimuli. We put forward the concept of symbolic EC to refer to changes in liking that occur because stimulus pairings function as symbols. The idea of symbolic EC is consistent with at least some current theories of persuasion. It clarifies what EC research can add to the understanding of the origins of our preferences and has implications for how (symbolic and non-symbolic) EC can be established, the boundaries of EC research, and cognitive and functional models of EC
Shedding light on the elusive role of endothelial cells in cytomegalovirus dissemination.
Cytomegalovirus (CMV) is frequently transmitted by solid organ transplantation and is associated with graft failure. By forming the boundary between circulation and organ parenchyma, endothelial cells (EC) are suited for bidirectional virus spread from and to the transplant. We applied Cre/loxP-mediated green-fluorescence-tagging of EC-derived murine CMV (MCMV) to quantify the role of infected EC in transplantation-associated CMV dissemination in the mouse model. Both EC- and non-EC-derived virus originating from infected Tie2-cre(+) heart and kidney transplants were readily transmitted to MCMV-naïve recipients by primary viremia. In contrast, when a Tie2-cre(+) transplant was infected by primary viremia in an infected recipient, the recombined EC-derived virus poorly spread to recipient tissues. Similarly, in reverse direction, EC-derived virus from infected Tie2-cre(+) recipient tissues poorly spread to the transplant. These data contradict any privileged role of EC in CMV dissemination and challenge an indiscriminate applicability of the primary and secondary viremia concept of virus dissemination
Reevaluating evaluative conditioning: A nonassociative explanation of conditioning effects in the visual evaluative conditioning paradigm
In 2 studies, the authors investigated whether evaluative conditioning (EC) is an associative phenomenon. Experiment 1 compared a standard EC paradigm with nonpaired and no-treatment control conditions. EC effects were obtained only when the conditioned stimulus (CS) and unconditioned stimulus (UCS) were rated as perceptually similar. However, similar EC effects were obtained in both control groups. An earlier failure to obtain EC effects was reanalyzed in Experiment 2. Conditioning-like effects were found when comparing a CS with the most perceptually similar UCSs used in the procedure but not when analyzing a CS rating with respect to the UCS with which it was paired during conditioning. The implications are that EC effects found in many studies are not due to associative learning and that the special characteristics of EC (conditioning without awareness and resistance to extinction) are probably nonassociative artifacts of the EC paradigm
When All Is Still Concealed: Are We Closer to Understanding the Mechanisms Underlying Evaluative Conditioning?
Fulcher and Hammerl's (2001) important exploration of the role of contingency awareness in evaluative conditioning (EC) raises a lot of issues for discussion: (1) what boundaries, if any, exist between EC and affective learning paradigms?; (2) if EC does occur without awareness does this mean it is nonpropositional learning?; (3) is EC driven by stimulus–response (S–R), rather than stimulus–stimulus (S–S), associations and if so should it then surprise us that contingency awareness is not important?; and (4) if S–R associations are at the heart of EC, should we automatically assume EC is part of a different learning mechanism to autonomic Pavlovian conditioning (Field, 2000a, 2000b)? This article, after a critical review of Fulcher and Hammerl's work, discusses these issues with reference to what can be realistically inferred about the mechanisms underlying EC
Direct measurement of electrocaloric effect in lead-free Ba(SnxTi1-x)O3 ceramics
In this study, we report on investigation of the electrocaloric (EC) effect in lead-free Ba(SnxTi1-x)O3 (BSnT) ceramics with compositions in the range of 0.08 ≤ x ≤ 0.15 by the direct measurement method using a differential scanning calorimeter. The maximum EC temperature change, ΔTEC-max = 0.63 K under an electric field of 2 kV/mm, was observed for the composition with x = 0.11 at ∼44 °C around the multiphase coexistence region. We observed that the EC effect also peaks at transitions between ferroelectric phases of different symmetries. Comparison with the results of indirect EC measurements from our previous work shows that the indirect approach provides reasonable estimations of the magnitude of the largest EC temperature changes and EC strength. However, it fails to describe correctly temperature dependences of the EC effect for the compositions showing relaxor-like behaviour (x = 0.14 and 0.15) because of their non-ergodic nature. Our study provides strong evidence supporting that looking for multiphase ferroelectric materials can be very useful to optimize EC performance
Co-Emergence of Specialized Endothelial Cells from Embryonic Stem Cells.
A well-formed and robust vasculature is critical to the health of most organ systems in the body. However, the endothelial cells (ECs) forming the vasculature can exhibit a number of distinct functional subphenotypes like arterial or venous ECs, as well as angiogenic tip and stalk ECs. In this study, we investigate the in vitro differentiation of EC subphenotypes from embryonic stem cells (ESCs). Using our staged induction methods and chemically defined mediums, highly angiogenic EC subpopulations, as well as less proliferative and less migratory EC subpopulations, are derived. Furthermore, the EC subphenotypes exhibit distinct surface markers, gene expression profiles, and positional affinities during sprouting. While both subpopulations contained greater than 80% VE-cad+/CD31+ cells, the tip/stalk-like EC contained predominantly Flt4+/Dll4+/CXCR4+/Flt-1- cells, while the phalanx-like EC was composed of higher numbers of Flt-1+ cells. These studies suggest that the tip-specific EC can be derived in vitro from stem cells as a distinct and relatively stable EC subphenotype without the benefit of its morphological positioning in the sprouting vessel
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