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Evidence is mixed on e-cigarette's effectiveness as a tobacco cessation aid. Research suggests that e-cigarette users face greater barriers to quitting tobacco.
To examine the association between e-cigarette use and tobacco cessation outcomes among quitline callers.
We examined 2,204 callers who enrolled and completed 7-month follow-up surveys between April 2014 and January 2017. We examined the association between any e-cigarette use and tobacco cessation. We also evaluated these relationships by e-cigarette use patterns between enrollment and 7-month follow-up: sustained, adopted, discontinued, and non-use. We used multivariable logistic regression to control for caller characteristics, tobacco history, and program utilization.
Overall, 18% of callers reported using e-cigarettes at enrollment, follow-up, or both. Compared to non-users, e-cigarette users were more likely to be younger, non-Hispanic, and report a mental health condition. The adjusted odds of tobacco cessation were not statistically different for callers who used e-cigarettes compared to those who did not (adjusted odds ratios = 1.02, 95% confidence interval 0.79–1.32). Results were similar when examining cessation by patterns of e-cigarette use.
E-cigarette use was not associated with tobacco cessation. This suggests that e-cigarette use may neither facilitate nor deter tobacco cessation among quitline callers. Future research should continue exploring how e-cigarette use affects quitting.
Based on a variable-coefficient Kadomtsev–Petviashvili (KP) equation, the topographic effect on the wave interactions between two oblique internal solitary waves is investigated. In the absence of rotation and background shear, the model set-up featuring idealised shoaling topography and continuous stratification is motivated by the large expanse of continental shelf in the South China Sea. When the bottom is flat, the evolution of an initial wave consisting of two branches of internal solitary waves can be categorised into six patterns depending on the respective amplitudes and the oblique angles measured counterclockwise from the transverse axis. Using theoretical multi-soliton solutions of the constant-coefficient KP equation, we select three observed patterns and examine each of them in detail both analytically and numerically. The effect of shoaling topography leads to a complicated structure of the leading waves and the emergence of two types of trailing wave trains. Further, the case when the along-crest width is short compared with the transverse domain of interest is examined and it is found that although the topographic effect can still modulate the wave field, the spreading effect in the transverse direction is dominant.
End-stage renal disease (ESRD) is a life-threatening illness that presents significant healthcare challenges. About 90% of ESRD patients receive hemodialysis treatment, but the currently available hemodialysis systems are bulky and prone to complications. We report the design of a microfluidic hemodialysis device composed of two polydimethylsiloxane (PDMS) chambers separated by a cellulose ester (CE) membrane. The polyethylene glycol-passivated PDMS and CE surfaces reduced platelet adhesion by 74% and 86%, respectively. Moreover, the device exhibited a higher urea clearance rate per unit area than a healthy kidney. The reported design sets the foundation for a next-generation biomimetic portable hemodialysis device.
The discovery of the first electromagnetic counterpart to a gravitational wave signal has generated follow-up observations by over 50 facilities world-wide, ushering in the new era of multi-messenger astronomy. In this paper, we present follow-up observations of the gravitational wave event GW170817 and its electromagnetic counterpart SSS17a/DLT17ck (IAU label AT2017gfo) by 14 Australian telescopes and partner observatories as part of Australian-based and Australian-led research programs. We report early- to late-time multi-wavelength observations, including optical imaging and spectroscopy, mid-infrared imaging, radio imaging, and searches for fast radio bursts. Our optical spectra reveal that the transient source emission cooled from approximately 6 400 K to 2 100 K over a 7-d period and produced no significant optical emission lines. The spectral profiles, cooling rate, and photometric light curves are consistent with the expected outburst and subsequent processes of a binary neutron star merger. Star formation in the host galaxy probably ceased at least a Gyr ago, although there is evidence for a galaxy merger. Binary pulsars with short (100 Myr) decay times are therefore unlikely progenitors, but pulsars like PSR B1534+12 with its 2.7 Gyr coalescence time could produce such a merger. The displacement (~2.2 kpc) of the binary star system from the centre of the main galaxy is not unusual for stars in the host galaxy or stars originating in the merging galaxy, and therefore any constraints on the kick velocity imparted to the progenitor are poor.
A study of the propagation of a mode-2 internal solitary wave over a slope-shelf topography is presented. The methodology is based on a variable-coefficient Korteweg–de Vries (vKdV) equation, using both analysis and numerical simulations, and simulations using the MIT general circulation model (MITgcm). Two configurations are considered. One is a mode-2 internal solitary wave propagating up the slope, from one three-layer system to another three-layer system. Depending on the height of the shelf, which determines the variation of the nonlinear coefficient of the vKdV equation, this can be classified into two cases. First, the case of a polarity change, in which the coefficient of the quadratic nonlinear term changes sign at a certain critical point on the slope, and second, the case with no such polarity change. In both these cases there is a small transfer of energy from the mode-2 wave to mode-1 waves. The other configuration is when the lower layer in the three-layer system goes to zero at a transition point on the slope, and beyond that point, there is a two-layer fluid system. A mode-2 internal solitary wave propagating up the slope cannot exist past this transition point. Instead it is extinguished and replaced by a mode-1 bore and trailing wave packet which moves onto the shelf.
Researchers have extensively studied how large firms and SMEs use business and political ties to obtain tangible and intangible resources in transition economies. However, how SMEs establish these ties in the context of power-imbalanced dependence by using unethical and illegal “strategic practice” such as bribery remains underexplored. Furthermore, how SMEs deploy strategies to mitigate such risky actions in the process of resource acquisition is also given limited attention in the literature. Lack of exploration of these issues leaves significant gaps in our understanding of how SMEs are able to initiate and operate their ties for survival and growth despite enormous institutional constraints. We analyze the negative and positive effects of power dependence on business resource acquisition via regression analysis using survey data drawn from 232 Chinese SMEs. The findings indicate that power-imbalanced dependence among SMEs is associated with their use of bribery to establish political ties with officials for access to resources. The moderating effect of power-mutual dependence on this relationship is also examined. Theoretical significance and managerial implications of these findings for SMEs in transition economies are discussed.
The SkyMapper 1.3 m telescope at Siding Spring Observatory has now begun regular operations. Alongside the Southern Sky Survey, a comprehensive digital survey of the entire southern sky, SkyMapper will carry out a search for supernovae and other transients. The search strategy, covering a total footprint area of ~2 000 deg2 with a cadence of ⩽5 d, is optimised for discovery and follow-up of low-redshift type Ia supernovae to constrain cosmic expansion and peculiar velocities. We describe the search operations and infrastructure, including a parallelised software pipeline to discover variable objects in difference imaging; simulations of the performance of the survey over its lifetime; public access to discovered transients; and some first results from the Science Verification data.
The objective of this study was to evaluate the potential of using Multiplex 3, a hand-held canopy fluorescence sensor, to determine rice nitrogen (N) status at different growth stages. In 2013, a paddy rice field experiment with five N fertilizer treatments and two varieties was conducted in Northeast China. Field samples and fluorescence data were collected simultaneously at the panicle initiation (PI), stem elongation (SE), and heading (HE) stages. Four N status indicators, leaf N concentration (LNC), plant N concentration (PNC), plant N uptake (PNU) and N nutrition index (NNI), were determined. The preliminary results indicated that different N application rates significantly affected most of the fluorescence variables, especially the simple fluorescence ratios (SFR_G, SFR_R), flavonoid (FLAV), and N balance indices (NBI_G, NBI_R). These variables were highly correlated with N status indicators. More studies are needed to further evaluate the accuracy of rice N status diagnosis using fluorescence sensing at different growth stages.
In this paper, the occurrence of the stimulated Raman scattering (SRS) and its effects on stimulated Brillouin scattering (SBS) pulse compression in FC-40 are investigated. As the experimental medium, the characteristics of FC-40 are suitable for pulse compression. Firstly, the frequency shifts and the threshold of SRS in FC-40 are studied with a mode-locked laser system as pump source, without taking the SBS effect into account. On the basis of the experimental results, the competition between SRS and SBS as well as its effect on pulse compression is investigated. Results show that SRS gets higher gain and grows rapidly with the increase of the laser intensity by pump effect, which will result in decreasing of SBS energy reflection.
This paper presents the first major data release and survey description for the ANU WiFeS SuperNovA Programme. ANU WiFeS SuperNovA Programme is an ongoing supernova spectroscopy campaign utilising the Wide Field Spectrograph on the Australian National University 2.3-m telescope. The first and primary data release of this programme (AWSNAP-DR1) releases 357 spectra of 175 unique objects collected over 82 equivalent full nights of observing from 2012 July to 2015 August. These spectra have been made publicly available via the WISEREP supernova spectroscopy repository.
We analyse the ANU WiFeS SuperNovA Programme sample of Type Ia supernova spectra, including measurements of narrow sodium absorption features afforded by the high spectral resolution of the Wide Field Spectrograph instrument. In some cases, we were able to use the integral-field nature of the Wide Field Spectrograph instrument to measure the rotation velocity of the SN host galaxy near the SN location in order to obtain precision sodium absorption velocities. We also present an extensive time series of SN 2012dn, including a near-nebular spectrum which both confirms its ‘super-Chandrasekhar’ status and enables measurement of the sub-solar host metallicity at the SN site.
Foxtail millet (Setaria italica (L.) P. Beauv.) is a naturally stress-tolerant plant, a major reserve crop and a model for panicoid grasses. The recent completion of the S. italica genome facilitates identification and characterization of WRKY transcription factor family proteins that are important regulators of major plant processes, including growth, development and stress response. The present study identified 103 WRKY transcription factor-encoding genes in the S. italica genome. The genes were named SiWRKY1–SiWRKY103 according to their order on the chromosomes. A comprehensive expression analysis of SiWRKY genes among four different tissues was performed using publicly available RNA sequencing data. Eighty-four SiWRKY genes were more highly expressed in root tissue than in other tissues and nine genes were only expressed in roots. Additionally, real-time quantitative polymerase chain reaction was performed to comprehensively analyse the expression of all SiWRKY genes in response to dehydration. Results indicated that most SiWRKY genes (over 0.8) were up-regulated by drought stress. In conclusion, genome-wide identification and expression profiling of SiWRKY genes provided a set of candidates for cloning and functional analyses in plants’ response to drought stress.
We report that the tail modulation of Stokes pulses in the high-energy stimulated Brillouin scattering pulse compression can be suppressed by controlling effective pulse width of the pump. It is shown through numerical simulations and validated experimentally that the effective pulse width is an appropriate parameter, which determines the generation of tail modulation. The effective pulse width broaden as the increase of energy. This mechanism leads to the amplification of Stokes tail edge and it is the cause of tail modulation.
We investigate the structure of an X-ray heated accretion disk in active galactic nuclei. It is found that X-ray heating can prevent the disk to be disrupted by its self-gravity under sufficient X-ray heating. The disk size can be two orders of magnitute larger than that limited by self-gravity of the disk without X-ray heating. An accretion disk corona will be formed by X-ray heating and can be a site for line emission. We present such emission line spectra which range from optical to hard X-ray energies and compare with the observational data.
Infectious bovine keratoconjunctivitis (IBK) is a common and important disease of calves. Without effective vaccines, antibiotic therapy is often implemented to minimize the impact of IBK. This review updates a previously published systematic review regarding comparative efficacy for antibiotic treatments of IBK. Available years of Centre for Biosciences and Agriculture International and MEDLINE databases were searched, including non-English results. Also searched were the American Association of Bovine Practitioners and World Buiatrics Congress conference proceedings from 1996 to 2016, reviews since 2013, reference lists from relevant trials, and U.S. Food and Drug Administration New Animal Drug Application summaries. Eligible studies assessed antibiotic treatment of naturally-occurring IBK in calves randomly allocated to group at the individual level. Outcomes of interest were clinical score, healing time, unhealed ulcer risk, and ulcer surface area. A mixed-effects model comparing active drug with placebo was employed for all outcomes. Heterogeneity was assessed visually and using Cochran's Q-test. Thirteen trials assessing nine treatments were included. Compared with placebo, most antibiotic treatments were effective. There was evidence that the treatment effect differed by day of outcome measurement. Visually, the largest differences were observed 7–14 days post-treatment. These results indicate improved IBK healing with many antibiotics and suggest the need for randomized trials comparing different antibiotic treatments.
A meter-wave sky survey of the region north of declination +30°, excluding only four fields straddling the Galactic plane (each 8° × 8° in angular size), has been conducted with the Miyun Synthesis Radio Telescope operating at 232 MHz. The reduced Miyun General Catalogue contains 34,426 radio sources in total. To distinguish which sources were not observed by other sky surveys, we first identify sources in the MGC with those in the 6C (151 MHz) catalogue, using a matching radius of 100 arcseconds. The remaining MGC objects were then matched with the B2/B3 (408 MHz), 4C (178 MHz), Texas (365 MHz, 1400 MHz) and 87GB (4.85 GHz) catalogues. 6850 MGC sources were found to lack any radio counterpart in these reference catalogues. It means 19.9% of sources listed in the MGC are probably new.
Sexual transmission has become the primary route of HIV transmission in China. Therefore, a comprehensive overview of HIV-1 subtype distribution is necessary for the prevention and control of the HIV epidemic. The present study aimed to provide a comprehensive prevalence estimate of different HIV-1 subtypes in sexual transmission in China. We conducted a systematic literature review for studies of HIV-1 subtypes in English and Chinese through several databases. Eligible articles were screened and selected by two authors independently. Random-effects model were applied to calculate the pooled prevalence of different HIV-1 subtypes, and subgroup analyses examined prevalence estimates across time, locations, and populations. A total of 130 eligible studies were identified, including 18 752 successfully genotyped samples. The pooled prevalence of CRF01_AE, subtype B, CRF07_BC, CRF08_BC, and subtype C were 44·54% (95% CI 40·81–48·30), 18·31% (95% CI 14·71–22·17), 16·45% (95% CI 13·82–19·25), 2·55% (95% CI 1·56–3·73), 0·37% (95% CI 0·11–0·72), respectively. The prevalence of subtype B in sexual transmission decreased, while the prevalence of CRF01_AE and CRF07_BC in sexual transmission, and CRF08_BC in heterosexual transmission increased. There is significant variation in HIV-1 subtype distribution between regions. The distribution of HIV-1 subtypes and circulating recombinant forms have changed significantly. The high genetic variability of HIV-1 poses a significant challenge for disease control and surveillance in China.
In late 2010, the online services giant Google released a tool for public use called the Google Books Ngram Viewer. The Ngram viewer was a Web interface that enabled virtually anyone with an Internet connection to run frequency searches of character strings in a corpus of more than 5.2 million digitized books, or roughly 500 billion words, published between the sixteenth and twenty-first centuries. With these massive corpora at hand, a new branch of humanistic research has been established, dubbed “culturomics” (Michel et al., 2011). Culturomics enables investigators to examine changes over time reflected in print material associated with the lexicon being used and can offer evidence of social patterns and orientations within a language community. For example, one could use the Ngram viewer to chart how often the word “slavery” was printed over time and see that it increased dramatically in the years leading up to the US Civil War and had since declined substantially. Similarly, one could look at the appearance of technological innovations, such as the radio and the telephone, in print material and infer that the rate of cultural adoption of these technologies has increased over time. These kinds of capabilities are not contingent on the existence of the Ngram Viewer, but rather reflective of how analysts can look toward word usage in print materials from different times to understand changes within a community and culture (e.g., Lieberman et al., 2007).
What would such an approach tell us about the learning sciences (LS)? Granted, the field spans decades rather than centuries, and the corpus of associated text is modest even against the wide range of education research literature published during the same period of time. However, it is our suspicion that even for a field that is still emerging and establishing its academic identity, an examination of frequency of word use across different times could be informative for our understanding of the field. This chapter summarizes some of our efforts to do that work. Building upon an analysis presented in 2012 (Lee, Ye, & Recker, 2012), we provide here an elaborated comparative analysis of proceedings from the first and the most recent (at the time of this writing) LS conferences (Birnbaum, 1991; Polman et al., 2014), as well as a third conference, roughly collocated with the first LS conference (Gomez, Lyons, & Radinsky, 2010).
The first observations by a worldwide network of advanced interferometric gravitational wave detectors offer a unique opportunity for the astronomical community. At design sensitivity, these facilities will be able to detect coalescing binary neutron stars to distances approaching 400 Mpc, and neutron star–black hole systems to 1 Gpc. Both of these sources are associated with gamma-ray bursts which are known to emit across the entire electromagnetic spectrum. Gravitational wave detections provide the opportunity for ‘multi-messenger’ observations, combining gravitational wave with electromagnetic, cosmic ray, or neutrino observations. This review provides an overview of how Australian astronomical facilities and collaborations with the gravitational wave community can contribute to this new era of discovery, via contemporaneous follow-up observations from the radio to the optical and high energy. We discuss some of the frontier discoveries that will be made possible when this new window to the Universe is opened.
Observations of the 2.6-mm line of C12O16 were made in the galactic plane from 1=105° to 150° at 1° intervals. The total velocity coverage is 83.2 km s−1 centered at −40 km s−1 with resolution equal to 0.65 km s−1. The observations were made first in June 1976 and confirmed in October 1977 after some improvement of the observing facilities at the Aerospace Corporation. The integration time in each direction is 15 minutes, giving 30-noise dispersions of 0.9K. Among the 46 directions, there are 18 CO detections. Twelve of them have CO components moving with the velocities typical of those expected for the Perseus Arm. Most of them are situated in or near the 0 associations or HII regions in the Perseus Arm, while the others lie in the regions rich in young star clusters. All the velocities observed are in excellent agreement with those expected in the post-shock region in the context of the shock formation model of the spiral density-wave theory. These molecular clouds may be viewed as being formed in the compression phase of the cloud medium as the individual clouds enter the shock front of the intercloud medium. Their line-of-sight velocities are in general a few km s−1 more negative than those of the HII regions, the young star clusters, and the O associations in the Perseus Arm. This suggests that these young objects may be formed prior to the observed CO clouds. The CO velocities are in agreement with those of the HI ridge. One CO cloud is observed at 1=148°, although it is well known that all the tracers of the spiral arm come to an abrupt stop at 1=140°.