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Peer crowd-based targeting in E-cigarette advertisements: a qualitative study to inform counter-marketing.
BACKGROUND:Cigarette lifestyle marketing with psychographic targeting has been well documented, but few studies address non-cigarette tobacco products. This study examined how young adults respond to e-cigarette advertisements featuring diverse peer crowds - peer groups with shared identities and lifestyles - to inform tobacco counter-marketing design. METHODS:Fifty-nine young adult tobacco users in California participated in interviews and viewed four to five e-cigarette advertisements that featured characters from various peer crowd groups. For each participant, half of the advertisements they viewed showed characters from the same peer crowd as their own, and the other half of the advertisements featured characters from a different peer crowd. Advertisements were presented in random order. Questions probed what types of cues are noticed in the advertisements, and whether and how much participants liked or disliked the advertisements. RESULTS:Results suggest that participants liked and provided richer descriptions of characters and social situations in the advertisements featuring their own peer crowd more than the advertisements featuring a different peer crowd. Mismatching age or device type was also noted: participants reported advertisements showing older adults were not intended for them. Participants who used larger vaporizers tended to dislike cigalike advertisements even if they featured a matching peer crowd. CONCLUSION:Peer crowd and lifestyle cues, age and device type are all salient features of e-cigarette advertising for young adults. Similarly, educational campaigns about e-cigarettes should employ peer crowd-based targeting to engage young adults, though messages should be carefully tested to ensure authentic and realistic portrayals
Metallicity Effect on LMXB Formation in Globular Clusters
We present comprehensive observational results of the metallicity effect on
the fraction of globular clusters (GC) that contain low-mass X-ray binaries
(LMXB), by utilizing all available data obtained with Chandra for LMXBs and HST
ACS for GCs. Our primary sample consists of old elliptical galaxies selected
from the ACS Virgo and Fornax surveys. To improve statistics at both the lowest
and highest X-ray luminosity, we also use previously reported results from
other galaxies. It is well known that the LMXB fraction is considerably higher
in red, metal-rich, than in blue, metal-poor GCs. In this paper, we test
whether this metallicity effect is X-ray luminosity-dependent, and find that
the effect holds uniformly in a wide luminosity range. This result is
statistically significant (at >= 3 sigma) in LMXBs with luminosities in the
range LX = 2 x 10^37 - 5 x 10^38 erg s-1, where the ratio of LMXB fractions in
metal-rich to metal-poor GCs is R = 3.4 +- 0.5. A similar ratio is also found
at lower (down to 10^36 erg s-1) and higher luminosities (up to the ULX
regime), but with less significance (~2 sigma confidence). Because different
types of LMXBs dominate in different luminosities, our finding requires a new
explanation for the metallicity effect in dynamically formed LMXBs. We confirm
that the metallicity effect is not affected by other factors such as stellar
age, GC mass, stellar encounter rate, and galacto-centric distance.Comment: 21 pages, 5 figures, accepted in Ap
Mobile moralities: ethical consumption in the digital realm
Ethical consumption, as a realm of production and exchange, as a framework for purchasing decisions and as political activism, is now well established in a range of nations. As a politics, it points to an interconnected but divergent set of concerns centred on issues of environmental sustainability, local and global economic and social justice, and community and individual wellbeing. While the subject of sustained critique, not least because of its apparent privileging of ‘the consumer’ as the locus of change, ethical consumption has garnered increasing attention. This is most recently evident in the development and widening use of ‘ethical consumption apps’ for mobile devices. These apps allow the user to both access ethical information on products and, potentially, to connect with a broader politics of consumption. However, in entering the digital realm ethical consumption also becomes embroiled in the complexities of digital technocultures and their ability to allow users of apps to be connected to each other, potentially building communities of interest and/or activism. This paper explores this emerging intersection of the ethical and the digital. It examines, in particular, whether such digital affordances affect the way ethical consumption itself may be conceived and pursued. Does the ethical consumption app work to collectivise or individualise, help to focus or fragment, speak of timidity or potential in relation to an oppositional politics of consumption? In confronting these issues, this paper suggests that contemporary ethical consumption apps – while full of political potential – remain problematic in that the turn to the digital has tended, so far, to accentuate the already individualising tendencies within a politics of ethical consumption. This speaks also, however, to a similar problematic in the politics of digital technocultures; the use of the digital does not automatically enable - merely through greater connectivity and information availability – forms of radical politics
Birds of Freedom? Perspectives on Female Emancipation and Sri Lanka’s Liberation Tigers of Tamil Eelam
Over the last decade, females have been an integral part of fighting forces in both international conflicts and in armed struggle in at least 38 internal conflicts. While some scholars argue that recent wars have thrust women into new roles, enabling them to transform their social situations, identities and destinies, others question whether females achieve ‘emancipation’ through active participation in warfare. The Liberation Tigers of Tamil Eelam (LTTE) in Sri Lanka that has been engaged in conflict with the Sri Lankan government since 1983, and actively recruits female cadres, provides an interesting context to explore issues of female empowerment in the context of armed struggle. Drawing from interviews with four Sri Lankans living in Canada, this paper traces the perceived extent of female emancipation within the LTTE. While the participation of females in unconventional military roles represents a drastic change in behavior expected of Tamil women, the militant movement appears to reinforce existing patterns of gender constructions, ultimately impeding the attainment of meaningful empowerment for females
Effect of magnetic Gd impurities on the superconducting state of amorphous Mo-Ge thin films with different thickness and morphology
pre-printWe studied the effect of magnetic doping with Gd atoms on the superconducting properties of amorphous Mo70Ge30 films. We observed that in uniform films deposited on amorphous Ge, the pair-breaking strength per impurity strongly decreases with film thickness initially and saturates at a finite value in films with thickness below the spin-orbit scattering length. The variation is likely caused by surface-induced magnetic anisotropy and is consistent with the fermionic mechanism of superconductivity suppression. In thin films deposited on SiN the pair-breaking strength becomes zero. Possible reasons for this anomalous response are discussed. The morphological distinctions between the films of the two types were identified using atomic force microscopy with a carbon nanotube tip
Surface Modification of Melt Extruded Poly(ε-caprolactone) Nanofibers: Toward a New Scalable Biomaterial Scaffold.
A photochemical modification of melt-extruded polymeric nanofibers is described. A bioorthogonal functional group is used to decorate fibers made exclusively from commodity polymers, covalently attach fluorophores and peptides, and direct cell growth. Our process begins by using a layered coextrusion method, where poly(ε-caprolactone) (PCL) nanofibers are incorporated within a macroscopic poly(ethylene oxide) (PEO) tape through a series of die multipliers within the extrusion line. The PEO layer is then removed with a water wash to yield rectangular PCL nanofibers with controlled cross-sectional dimensions. The fibers can be subsequently modified using photochemistry to yield a "clickable" handle for performing the copper-catalyzed azide-alkyne cycloaddition (CuAAC) reaction on their surface. We have attached fluorophores, which exhibit dense surface coverage when using ligand-accelerated CuAAC reaction conditions. In addition, an RGD peptide motif was coupled to the surface of the fibers. Subsequent cell-based studies have shown that the RGD peptide is biologically accessible at the surface, leading to increased cellular adhesion and spreading versus PCL control surfaces. This functionalized coextruded fiber has the advantages of modularity and scalability, opening a potentially new avenue for biomaterials fabrication
IR-Level Versus Machine-Level If-Conversion for Predicated Architectures
If-conversion is a simple yet powerful optimization that converts control dependences into data dependences. It allows elimination of branches and increases available instruction level parallelism and thus overall performance. If-conversion can either be applied alone or in combination with other techniques that increase the size of scheduling regions. The presence of hardware support for predicated execution allows if-conversion to be broadly applied in a given program. This makes it necessary to guide the optimization using heuristic estimates regarding its potential benefit. Similar to other transformations in an optimizing compiler, if-conversion inherently su↵ers from phase ordering issues. Driven by these facts, we developed two algorithms for if-conversion targeting the TI TMS320C64x+ architecture within the LLVM framework. Each implementation targets a di↵erent level of code abstraction. While one targets the intermediate representation, the other addresses machine-level code. Both make use of an adapted set of estimation heuristics and prove to be successful in general, but each one exhibits di↵erent strengths and weaknesses. High-level if-conversion, applied before other control flow transformations, has more freedom to operate. But in contrast to its machine-level counterpart, which is more restricted, its estimations of runtime are less accurate. Our results from experimental evaluation show a mean speedup close to 14 % for both algorithms on a set of programs from the MiBench and DSPstone benchmark suites. We give a comparison of the implemented optimizations and discuss gained insights on the topics of ifconversion, phase ordering issues and profitability analysis
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