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The use of electronic cigarettes (e-cigarettes) in smokers with mental health conditions (MHC) is not well understood.
This study aims to compare e-cigarette users and non-users among veteran smokers with MHC to characterize differences in smoking behavior, motivation to quit, psychological distress, primary psychiatric diagnosis, and other factors.
Baseline survey data were used from a randomized smoking cessation trial enrolling smokers with MHC from four Veterans Health Administration hospitals. Participants were categorized as current, former (having ever tried an e-cigarette), or never e-cigarette users. Pearson's χ2 and ANOVA Type-3 F-tests were used to test the bivariate associations between e-cigarette use and variables measured.
Among 1,836 participants, mean age was 58 years (STD ± 12.5), 87% were male, 15% were current e-cigarette users (n = 275), and 27% were former users (n = 503). Sixty-five percent of e-cigarette users reported ‘wanting to quit smoking’ as a primary reason. Mean readiness to quit smoking (1–10) was 7.2, 6.8, and 6.4 for current, former, and never e-cigarette users, respectively (P = 0.0002). Sixty-three percent of current and former users and 55% of never-users reported some mental distress on Kessler-6 scale (P = 0.0003, OR = 1.4, 95% CI 1.1–1.7). A primary psychiatric diagnosis of alcohol or substance use disorder was recorded for 50% of current or former users and 60% of never-users (P = 0.0003, OR = 0.69, 95% CI 0.56–0.84).
E-cigarette users were more ready to quit and most often reported using e-cigarettes to assist with quitting. E-cigarette users had more psychological distress and were less likely to have substance use disorders as their primary psychiatric diagnosis.
The need for hollow microneedle arrays is important for both drug delivery and wearable sensor applications; however, their fabrication poses many challenges. Hollow metal microneedle arrays residing on a flexible metal foil substrate were created by combining additive manufacturing, micromolding, and electroplating approaches in a process we refer to as electromolding. A solid microneedle with inward facing ledge was fabricated with a two photon polymerization (2PP) system utilizing laser direct write (LDW) and then molded with polydimethylsiloxane. These molds were then coated with a seed layer of Ti/Au and subsequently electroplated with pulsed deposition to create hollow microneedles. An inward facing ledge provided a physical blocking platform to restrict deposition of the metal seed layer for creation of the microneedle bore. Various ledge sizes were tested and showed that the resulting seed layer void could be controlled via the ledge length. Mechanical properties of the PDMS mold was adjusted via the precursor ratio to create a more ductile mold that eliminated tip damage to the microneedles upon removal from the molds. Master structures were capable of being molded numerous times and molds were able to be reused. SEM/EDX analysis showed that trace amounts of the PDMS mold were transferred to the metal microneedle upon removal. The microneedle substrate showed a degree of flexibility that withstood over 100 cycles of bending from side to side without damaging. Microneedles were tested for their fracture strength and were capable of puncturing porcine skin and injecting a dye.
More than 60 years ago, Angus Campbell offered an explanation for why the president’s party regularly loses congressional seats in midterm elections. He argued that peripheral voters “surge” to the polls in presidential elections and support the president’s congressional co-partisans but “decline” to turn out in the midterm. In his turnout-based explanation for midterm loss, Campbell speculated that “bad weather or an epidemic may affect the vote” but largely dismissed weather’s utility to test his theory (Campbell 1960, 399). I revisit Campbell’s speculation and employ a new identification strategy to investigate the “surge and decline” account of midterm loss. I show that as the costs of voting increase—due to above-average rainfall on Election Day—the strength of the relationship between presidential and congressional voting weakens.
The growth of Ag on ZnO was modeled using a reactive force field potential and a combination of molecular dynamics and adaptive kinetic Monte Carlo (AKMC) simulations. An adaptive lattice-based AKMC model is described as a method of extending timescales and length scales that can be simulated. Reusing previously found transitions to reduce computational time is discussed for both the lattice and off-lattice AKMC approaches. With these methods, growth of over 1 monolayer’s worth of Ag is simulated corresponding to a real deposition time of up to 0.1 s. The results show that the deposited silver aggregates on the surface through mainly single atom moves with few concerted motions. Initially silver adatoms do not agglomerate and the energy barriers for silver dimers to form are larger than for them to break apart. The first layer of silver grows as a series of connected regions rather than forming well-defined centro-symmetric islands.
The existing spectral searches for quasars have increased the number of quasars known very substantially but have not contributed proportionately to an understanding of the collective properties because of the selection effects. To fully exploit the spectral searches we have developed the technique of automated quasar detection (AQD) using objective-prism plates from the UK Schmidt Telescope, the COSMOS measuring machine at the Royal Observatory Edinburgh, and the STARLINK nodes at Durham and Edinburgh.
We have obtained estimates of the solar internal rotational velocity from measurements of the frequency splittings of p-mode oscillations. Specifically, we have analyzed a 10-day time series of full-disk Dopplergrams obtained during July and August 1984 at the 60-Foot Tower Telescope of the Mt. Wilson Observatory. The Dopplergrams were obtained with a Na magneto-optical filter and a 244 × 248-pixel CID camera. From the time series we computed power spectra for all of the prograde and retrograde sectoral p-modes from ℓ = 0 to 200 and for all of the tessaral harmonics up to ℓ = 89. We then applied a cross-correlation analysis to the resulting sectoral power spectra to obtain estimates of the frequency splittings. From ℓ = 4 to ℓ = 30 we obtained a mean value of the frequency spitting of roughly 450 nHz (sidereal) in close agreement with most previously published results, while from ℓ = 40 to ℓ = 140 we obtained a mean value of about 470 nHz. We believe that the latter value is slightly higher than the surface rotational splitting of 461 nHz because of possible confusion due to the temporal sidelobes introduced by the day/night observing cycle. Confirmation of this possibility will have to await our computation of tesseral power spectra for degrees greater than our current limit of 89. Finally, for degrees between 140 and 200, the frequency splittings are indistinguishable from the surface rotation rate.
Remotely sensed derivation of sea-ice thickness requires sea·ice density. Sea-ice density was estimated with three techniques during the second Sea Ice Physics and Ecosystem eXperimett (SIPEX-II, September-November 2012, East Antarctica). The sea ice was first-year highly deformed, mean thicknsss 1.2 m with layers, consistent with rafting, and 6-7/10 columnar ice and 3/10 granular ice. Ice density was found to be lower than values (900-920 kg m−3 used previously to derive ice thickness,, with columnar ice mean density of 870 kg m− 3. At two different ice stations the mean density of the ice was 800 kg m–3, the lower density reflecting a high percentage of porous granular ice at the second station. Error estimates for mass/volume and liquid/solid water methods are presented. With 0.1 m long, 0.1 m core samples, the error on individual density estimates is 28 kg m-3. Errors are larger for smaller machined blocks. Errors increase to 46 kg m-3 if the liquid/solid volume method is used. The mass/vouume method has a low bias due to brine drainage of at least 5%. Bulk densities estimated from ice and snow measurements along 100 m transects were high, and likely unrealistic as the assumption of isostatcc balance is not suitable over these length scales in deformed ice.
Theories of electoral accountability predict that legislators will receive fewer votes if they fail to represent their districts. To determine whether this prediction applies to state legislators, I conduct two analyses that evaluate the extent to which voters sanction legislators who cast unpopular roll-call votes or provide poor ideological representation. Neither analysis, however, produces compelling evidence that elections hold most state legislators accountable. I discover that legislators do not face meaningful electoral consequences for their ideological representation, particularly in areas where legislators receive less media attention, have larger staffs, and represent more partisan districts. In a study of individual roll-call votes across 11 states, I furthermore find a weak relationship between legislators’ roll-call positions and election outcomes with voters rewarding or punishing legislators for only 4 of 30 examined roll calls. Thus, while state legislators wield considerable policymaking power, elections do not appear to hold many legislators accountable for their lawmaking.
The Murchison Widefield Array is a Square Kilometre Array Precursor. The telescope is located at the Murchison Radio–astronomy Observatory in Western Australia. The MWA consists of 4 096 dipoles arranged into 128 dual polarisation aperture arrays forming a connected element interferometer that cross-correlates signals from all 256 inputs. A hybrid approach to the correlation task is employed, with some processing stages being performed by bespoke hardware, based on Field Programmable Gate Arrays, and others by Graphics Processing Units housed in general purpose rack mounted servers. The correlation capability required is approximately 8 tera floating point operations per second. The MWA has commenced operations and the correlator is generating 8.3 TB day−1 of correlation products, that are subsequently transferred 700 km from the MRO to Perth (WA) in real-time for storage and offline processing. In this paper, we outline the correlator design, signal path, and processing elements and present the data format for the internal and external interfaces.
It is generally accepted that Léon Walras's greatest influence on American and British economics began only in the 1930s. While there is a significant element of truth to this, it begs the question of the degree to which Walras's work was known in the English-speaking world prior to the 1930s. Economists sometimes write as if there was a rediscovery of Walras in the 1930s, which raises the question of what American economists already knew about his work and how they had responded to it. Pascal Bridel has tackled this problem through analysing the reviews of Walras's books, and Walker has provided both a brief overview of these connections and a selection of the more recent literature illustrating Walras's influence. This essay extends this work through a systematic analysis of how his ideas were received in the main English-language journals.
The period chosen is 1890 to 1939, which coincides with what might be described, somewhat loosely, as the ‘Age of Marshall’ in English-speaking economics. This epoch began with the publication of his Principles of Economics (1890), the influence of which on British and American economics was unparalleled for more than two decades. By the 1930s, however, Marshall's work was being widely challenged and some looked to Walras in developing an alternative way forward.
We present the results of an approximately 6 100 deg2 104–196 MHz radio sky survey performed with the Murchison Widefield Array during instrument commissioning between 2012 September and 2012 December: the MWACS. The data were taken as meridian drift scans with two different 32-antenna sub-arrays that were available during the commissioning period. The survey covers approximately 20.5 h < RA < 8.5 h, − 58° < Dec < −14°over three frequency bands centred on 119, 150 and 180 MHz, with image resolutions of 6–3 arcmin. The catalogue has 3 arcmin angular resolution and a typical noise level of 40 mJy beam− 1, with reduced sensitivity near the field boundaries and bright sources. We describe the data reduction strategy, based upon mosaicked snapshots, flux density calibration, and source-finding method. We present a catalogue of flux density and spectral index measurements for 14 110 sources, extracted from the mosaic, 1 247 of which are sub-components of complexes of sources.
Significant new opportunities for astrophysics and cosmology have been identified at low radio frequencies. The Murchison Widefield Array is the first telescope in the southern hemisphere designed specifically to explore the low-frequency astronomical sky between 80 and 300 MHz with arcminute angular resolution and high survey efficiency. The telescope will enable new advances along four key science themes, including searching for redshifted 21-cm emission from the EoR in the early Universe; Galactic and extragalactic all-sky southern hemisphere surveys; time-domain astrophysics; and solar, heliospheric, and ionospheric science and space weather. The Murchison Widefield Array is located in Western Australia at the site of the planned Square Kilometre Array (SKA) low-band telescope and is the only low-frequency SKA precursor facility. In this paper, we review the performance properties of the Murchison Widefield Array and describe its primary scientific objectives.
After the 2012 Republican New Hampshire primary, 159 poll results were released prior to the subsequent nomination contests in the Republican presidential primary. More than two-thirds of these polls relied on interactive voice response (IVR) software to conduct the interviews. We evaluate the ability of polls to predict the vote-share for the Republican candidates Romney, Santorum, and Gingrich. We find no overall difference in the average accuracy of IVR and traditional human polls, but IVR polls conducted prior to human polls are significantly poorer predictors of election outcomes than traditional human polls even after controlling for characteristics of the states, polls, and electoral environment. These findings provide suggestive, but not conclusive, evidence that pollsters may take cues from one another given the stakes involved. If so, reported polls should not be assumed to be independent of one another and so-called poll-of-polls will be misleadingly precise.
We have examined the properties of helium bubbles in Fe using two different Fe-He potentials. The atomic configurations and formation energies of different He-vacancy complexes are determined and their stability in the region of nearby collision cascades is investigated. The results show that the optimal He to Fe vacancy ratio increases from about 1:1 for approximately 5 vacancies up to about 4:1 for 36 vacancies. Collision cascades initiated near the complex show that Fe vacancies produced by the cascades readily become part of the He-vacancy complexes. The energy barrier for an isolated He interstitial to diffuse was found to be 0.06 eV. Thus a possible mechanism for He bubble growth would be the addition of vacancies during a radiation event followed by the subsequent accumulation of mobile He interstitials produced by the corresponding nuclear reaction.
The Murchison Widefield Array (MWA) is one of three Square Kilometre Array Precursor telescopes and is located at the Murchison Radio-astronomy Observatory in the Murchison Shire of the mid-west of Western Australia, a location chosen for its extremely low levels of radio frequency interference. The MWA operates at low radio frequencies, 80–300 MHz, with a processed bandwidth of 30.72 MHz for both linear polarisations, and consists of 128 aperture arrays (known as tiles) distributed over a ~3-km diameter area. Novel hybrid hardware/software correlation and a real-time imaging and calibration systems comprise the MWA signal processing backend. In this paper, the as-built MWA is described both at a system and sub-system level, the expected performance of the array is presented, and the science goals of the instrument are summarised.