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Making Change: Diffusion of Technological, Relational, and Cultural Innovation in the Newsroom
Diffusion of innovations theory typically has been applied to the spread of a particular technology or practice rather than the interplay of a cluster of innovations. This case study of a news company undergoing significant change seeks to offer a deeper understanding of multifaceted industry upheaval by considering the diffusion of three interdependent yet distinct changes. Findings suggest technological change faces the fewest hurdles, as journalists recognize the need to adapt their practices to newer capabilities. Changes to audience relationships face greater resistance, while responses to changes to the professional culture of journalism remain the most tepid
NuSTAR Observations of Four Mid-IR Selected Dual AGN Candidates in Galaxy Mergers
Mergers of galaxies are a ubiquitous phenomenon in the Universe and represent
a natural consequence of the ``bottom-up'' mass accumulation and galaxy
evolution cosmological paradigm. It is generally accepted that the peak of AGN
accretion activity occurs at nuclear separations of kpc for major
mergers. Here we present new NuSTAR and XMM-Newton observations for a subsample
of mid-IR preselected dual AGN candidates in an effort to better constrain the
column densities along the line-of-sight for each system. Only one dual AGN
candidate, J0841+0101, is detected as a single, unresolved source in the
XMM-Newton and NuSTAR imaging, while the remaining three dual AGN candidates,
J0122+0100, J1221+1137, and J1306+0735, are not detected with NuSTAR; if these
non-detections are due to obscuration alone, these systems are consistent with
being absorbed by column densities of log()
24.9, 24.8, and 24.6, which are roughly consistent with previously inferred
column densities in these merging systems. In the case of J0841+0101, the
analysis of the 0.3-30 keV spectra reveal a line-of-sight column density of
cm, significantly larger than the column
densities previously reported for this system and demonstrating the importance
of the higher signal-to-noise XMM-Newton spectra and access to the keV
energies via NuSTAR. Though it is unclear if J0841+0101 truly hosts a dual AGN,
these results are in agreement with the high obscuring columns expected in AGNs
in late-stage mergers.Comment: 21 pages, 9 tables, 4 figures. Accepted for publication in Ap
Use of contingency management incentives to improve completion of hepatitis B vaccination in people undergoing treatment for heroin dependence: a cluster randomised trial
Background: Poor adherence to treatment diminishes its individual and public health benefit. Financial incentives, provided on the condition of treatment attendance, could address this problem. Injecting drug users are a high-risk group for hepatitis B virus (HBV) infection and transmission, but adherence to vaccination programmes is poor. We aimed to assess whether contingency management delivered in routine clinical practice increased the completion of HBV vaccination in individuals receiving opioid substitution therapy.
Methods: In our cluster randomised controlled trial, we enrolled participants at 12 National Health Service drug treatment services in the UK that provided opioid substitution therapy and nurse-led HBV vaccination with a super-accelerated schedule (vaccination days 0, 7, and 21). Clusters were randomly allocated 1:1:1 to provide vaccination without incentive (treatment as usual), with fixed value contingency management (three £10 vouchers), or escalating value contingency management (£5, £10, and £15 vouchers). Both contingency management schedules rewarded
on-time attendance at appointments. The primary outcome was completion of clinically appropriate HBV vaccination within 28 days. We also did sensitivity analyses that examined vaccination completion with full adherence to appointment times and within a 3 month window. The trial is registered with Current Controlled Trials, number ISRCTN72794493.
Findings: Between March 16, 2011, and April 26, 2012, we enrolled 210 eligible participants. Compared with six (9%) of 67 participants treated as usual, 35 (45%) of 78 participants in the fixed value contingency management group met the primary outcome measure (odds ratio 12·1, 95% CI 3·7–39·9; p<0·0001), as did 32 (49%) of 65 participants in the escalating value contingency management group (14·0, 4·2–46·2; p<0·0001). These differences remained significant with sensitivity analyses.
Interpretation: Modest financial incentives delivered in routine clinical practice significantly improve adherence to, and completion of, HBV vaccination programmes in patients receiving opioid substitution therapy. Achievement of this improvement in routine clinical practice should now prompt actual implementation. Drug treatment providers should employ contingency management to promote adherence to vaccination programmes. The effectiveness of
routine use of contingency management to achieve long-term behaviour change remains unknown
The Messy Nature of Fiber Spectra: Star-Quasar Pairs Masquerading as Dual Type 1 AGNs
Theoretical studies predict that the most significant growth of supermassive
black holes occurs in late-stage mergers, coinciding with the manifestation of
dual active galactic nuclei (AGNs), and both major and minor mergers are
expected to be important for dual AGN growth. In fact, dual AGNs in minor
mergers should be signposts for efficient minor merger-induced SMBH growth for
both the more and less massive progenitor. We identified two candidate dual
AGNs residing in apparent minor mergers with mass ratios of 1:7 and
1:30. SDSS fiber spectra show broad and narrow emission lines in the
primary nuclei of each merger while only a narrow [O III] emission line and a
broad and prominent H/[N II] complex is observed in the secondary
nuclei. The FWHMs of the broad H lines in the primary and secondary
nuclei are inconsistent in each merger, suggesting that each nucleus in each
merger hosts a Type 1 AGN. However, spatially-resolved LBT optical spectroscopy
reveal rest-frame stellar absorption features, indicating the secondary sources
are foreground stars and that the previously detected broad lines are likely
the result of fiber spillover effects induced by the atmospheric seeing at the
time of the SDSS observations. This study demonstrates for the first time that
optical spectroscopic searches for Type 1/Type 1 pairs similarly suffer from
fiber spillover effects as has been observed previously for Seyfert 2 dual AGN
candidates. The presence of foreground stars may not have been clear if an
instrument with more limited wavelength range or limited sensitivity had been
used.Comment: 15 pages including appendix and references, 6 figures, 1 table.
Accepted for publication in Ap
Efficacy of Online Training for Improving Camp Staff Competency
Preparing competent staff is a critical issue within the camp community. This quasi-experimental study examined the effectiveness of an online course for improving staff competency in camp healthcare practices among college-aged camp staff and a comparison group (N = 55). We hypothesized that working in camp would increase competency test scores due to opportunities for staff to experientially apply knowledge learned online. Hierarchical linear modeling was used to analyse the cross-level effects of a between-individuals factor (assignment to experimental or comparison group) and within-individual effects of time (pre-test, post-test #1, and post-test #2) on online course test scores. At post-test #2, the difference in average test scores between groups was ~30 points, with the treatment group scoring lower on average than the comparison group. Factors that may have influenced these findings are explored, including fatigue and the limited durability of online learning. Recommendations for research and practice are discussed
ACCESS: An optical transmission spectrum of the high-gravity, hot Jupiter HAT-P-23b
We present a new ground-based visible transmission spectrum of the
high-gravity, hot Jupiter HAT-P-23b, obtained as part of the ACCESS project. We
derive the spectrum from five transits observed between 2016 and 2018, with
combined wavelength coverage between 5200 {\AA} - 9269 {\AA} in 200 {\AA} bins,
and with a median precision of 247 ppm per bin. HAT-P-23b's relatively high
surface gravity (g ~ 30 m/s^2), combined with updated stellar and planetary
parameters from Gaia DR2, gives a 5-scale-height signal of 384 ppm for a
hydrogen-dominated atmosphere. Bayesian models favor a clear atmosphere for the
planet with the tentative presence of TiO, after simultaneously modeling
stellar contamination, using spots parameter constraints from photometry. If
confirmed, HAT-P-23b would be the first example of a high-gravity gas giant
with a clear atmosphere observed in transmission at optical/NIR wavelengths;
therefore, we recommend expanding observations to the UV and IR to confirm our
results and further characterize this planet. This result demonstrates how
combining transmission spectroscopy of exoplanet atmospheres with long-term
photometric monitoring of the host stars can help disentangle the exoplanet and
stellar activity signals.Comment: 28 pages, 18 Figures, accepted for publication in AJ. arXiv admin
note: text overlap with arXiv:1911.0335
Open Sequence Initiative: a part submission standard to complement modern DNA assembly techniques
The discipline of synthetic biology emphasizes the application of engineering principles such as standardization, abstraction, modularity, and rational design to complex biological systems. The archetypical example of such standardization is BioBrick RFC[10], introduced in 2003 by Tom Knight at MIT. BioBricks are stored on a standard plasmid, pSB1C3, which contains prefix and suffix sequences flanking the DNA sequence specifying a biological part. The prefix and suffix sequences contain two pairs of 6 base-pair (bp) restriction enzyme sites (EcoRI+XbaI and SpeI+PstI), which can be used for both part assembly and quality control. BioBricks are intended to be well- characterized biological parts, such as genes or promoters, that function in a predictable fashion and can be readily combined to make complex systems. The rules of the RFC[10] BioBrick assembly method require that none of the restriction sites used in the prefix and suffix be present in the parts themselves. This requirement can be an onerous imposition for iGEM teams developing large, novel parts, such as genes or entire operons that are obtained by amplifying DNA sequences from environmental samples or microorganisms.
While iGEM teams may use methods such as site-directed mutagenesis to remove illegal restriction sites from a part's sequence, it is certainly possible that this mutation will alter the functionality of the part – a very undesirable outcome. In addition, the mutagenesis of illegal restriction sites is an unnecessary burden on teams, given the limited time and resources available to teams during each year’s iGEM competition. Efforts spent mutagenizing sites would be better spent characterizing and improving parts. This RFC proposes an alternative submission standard to eliminate these problems
Genetic diversity of Brazilian isolates of feline immunodeficiency virus
We isolated Feline immunodeficiency virus (FIV) from three adult domestic cats, originating from two open shelters in Brazil. Viruses were isolated from PBMC following co-cultivation with the feline T-lymphoblastoid cell line MYA-1. All amplified env gene products were cloned directly into pGL8MYA. The nucleic acid sequences of seven clones were determined and then compared with those of previously described isolates. The sequences of all of the Brazilian virus clones were distinct and phylogenetic analysis revealed that all belong to subtype B. Three variants isolated from one cat and two variants were isolated from each of the two other cats, indicating that intrahost diversity has the potential to pose problems for the treatment and diagnosis of FIV infection
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