Polarized point sources in the LOFAR Two-meter Sky Survey: A preliminary catalog

The polarization properties of radio sources at very low frequencies (h45m–15h30m right ascension, 45°–57° declination, 570 square degrees). We have produced a catalog of 92 polarized radio sources at 150 MHz at 4.′3 resolution and 1 mJy rms sensitivity, which is the largest catalog of polarized sources at such low frequencies. We estimate a lower limit to the polarized source surface density at 150 MHz, with our resolution and sensitivity, of 1 source per 6.2 square degrees. We find that our Faraday depth measurements are in agreement with previous measurements and have significantly smaller errors. Most of our sources show significant depolarization compared to 1.4 GHz, but there is a small population of sources with low depolarization indicating that their polarized emission is highly localized in Faraday depth. We predict that an extension of this work to the full LOTSS data would detect at least 3400 polarized sources using the same methods, and probably considerably more with improved data processing

Treatment with 2-AAF blocks the small hepatocyte-like progenitor cell response in retrorsine-exposed rats

Liver regeneration after partial hepatectomy (PH) in retrorsine-exposed rats is accomplished through proliferation and differentiation of small hepatocyte-like progenitor cells (SHPCs). The cells of origin of SHPCs are not known. We investigated the possibility that SHPCs are directly derived from oval cells, a known liver progenitor cell, by combining the retrorsine/PH (RP) model with 2-acetamidofluorene (2-AAF), an anti-mitotic agent that elicits an oval cell reaction in response to liver deficit

Mobilising knowledge in complex health systems: A call to action

Worldwide, policymakers, health system managers, practitioners and researchers struggle to use evidence to improve policy and practice. There is growing recognition that this challenge relates to the complex systems in which we work. The corresponding increase in complexity-related discourse remains primarily at a theoretical level. This paper moves the discussion to a practical level, proposing actions that can be taken to implement evidence successfully in complex systems. Key to success is working with, rather than trying to simplify or control, complexity. The integrated actions relate to co-producing knowledge, establishing shared goals and measures, enabling leadership, ensuring adequate resourcing, contributing to the science of knowledge-to-action, and communicating strategically. This is the final version of the article. It first appeared from Policy Press via http://dx.doi.org/10.1332/174426416X1471255375031

Development and implementation of a structured intervention for alcohol use disorders for telephone helpline services

A six-session intervention for harmful alcohol use was piloted via a 24-hour alcohol and other drug (AOD) helpline, assessing feasibility of telephone-delivered treatment. The intervention, involving practice elements from Motivational Interviewing, Cognitive-Behavioral Therapy, and node-link mapping, was evaluated using a case file audit (n D 30) and a structured telephone interview one month after the last session (n D 22). Average scores on the Alcohol Use Disorder Identification Test (AUDIT) dropped by more than 50%, and there were significant reductions in psychological distress. Results suggest that, even among dependent drinkers, a telephone intervention offers effective and efficient treatment for those unable or unwilling to access face-to-face treatment

Signaling Mechanisms of Vav3, a Guanine Nucleotide Exchange Factor and Androgen Receptor Coactivator, in Physiology and Prostate Cancer Progression

The Rho GTPase guanine nucleotide exchange factor (GEF) Vav3 is the third member of the Vavfamily of GEFS and is activated by tyrosine phosphorylation. Through stimulation of Rho GTPaseactivity, Vav3 promotes cell migration, invasion, and other cellular processes. Work from our laboratory first established that Vav3 is upregulated in models of castration-resistant prostate cancer progression and enhances androgen receptor as well as androgen receptor splice variant activity. Recent analysis of clinical specimens supports Vav3 as a potential biomarker of aggressive prostate cancer. Consistent with a role in promoting castration-­resistant disease, Vav3 is a versatile enhancer of androgen receptor by both ligand-dependent and ligand-independent mechanisms and as such impacts established pathways of androgen receptor reactivation in advanced prostate cancer. Distinct Vav3 domains and mechanisms participate in ligand-dependent and -independent androgen receptor coactivation. To provide a physiologic context, we review Vav3 actions elucidated by gene knockout studies. This chapter describes the pervasive role of Vav3 in progression of prostate cancer to castration resistance. We discuss the mechanisms by which prostate cancer cells exploit Vav3 signaling to promote androgen receptor activity under different hormonal milieus, which are relevant to clinical prostate cancer. Lastly, we review the data on the emerging role for Vav3 in other cancers ranging from leukemias to gliomas.https://nsuworks.nova.edu/hpd_medsci_faculty_books/1002/thumbnail.jp

PCDB: a database of protein conformational diversity

PCDB (http://www.pcdb.unq.edu.ar) is a database of protein conformational diversity. For each protein, the database contains the redundant compilation of all the corresponding crystallographic structures obtained under different conditions. These structures could be considered as different instances of protein dynamism. As a measure of the conformational diversity we use the maximum RMSD obtained comparing the structures deposited for each domain. The redundant structures were extracted following CATH structural classification and cross linked with additional information. In this way it is possible to relate a given amount of conformational diversity with different levels of information, such as protein function, presence of ligands and mutations, structural classification, active site information and organism taxonomy among others. Currently the database contains 7989 domains with a total of 36581 structures from 4171 different proteins. The maximum RMSD registered is 26.7 Å and the average of different structures per domain is 4.5

A critical insight into practitioners’ lived experience of payment by results in the alcohol and drug treatment sector

Since former Chancellor George Osborne described reducing public spending as ‘the great national challenge of our generation’ (Her Majesty’s Treasury, 2010: 12) the UK Government have demonstrated a profound interest in Payment by Results (PbR) as a mechanism to improve service quality, value for money and innovation (Audit Commission, 2012). Although PbR is not a new initiative, it has been rebranded and sold as a vehicle that can steer ongoing strategies for reform, particularly in the field of criminal justice and drug/alcohol treatment (Her Majesty’s Government, 2010; Ministry of Justice 2013). Despite such assertions, the initiative has become synonymous with budget cuts (Community Links, 2015), the privatisation of public services (Policy Exchange, 2013) and controversy. Drawing upon the findings of a focus group with staff who work in a Therapeutic Community, this article highlights the lived experience of practitioners as PbR takes hold of the alcohol and drug treatment sector. The findings suggest that outcome-orientated incentives, such as PbR, hold the potential to transform welfare-orientated sectors into a financial, market-focused milieu

Radiative age mapping of the remnant radio galaxy B2 0924+30: the LOFAR perspective

We have observed the steep spectrum radio source B2 0924+30 using the LOw Frequency ARray (LOFAR) telescope. Hosted by a z = 0.026 elliptical galaxy, it has a relatively large angular size of 12′ (corresponding to 360 kpc projected linear size) and a morphology reminiscent of a remnant Fanaroff-Riley type II (FRII) radio galaxy. Studying active galactic nuclei (AGN) radio remnants can give us insight into the time-scales involved into the episodic gas accretion by AGNs and their dependence on the AGN host environment. The proximity of the radio galaxy allows us to make detailed studies of its radio structure and map its spectral index and radiative age distribution. We combine LOFAR and archival images to study the spectral properties at a spatial resolution of 1′. We derive low frequency spectral index maps and use synchrotron ageing models to infer ages for different regions of the source. Thus, we are able to extend the spectral ageing studies into a hitherto unexplored frequency band, adding more robustness to our results. Our detailed spectral index mapping, while agreeing with earlier lower resolution studies, shows flattening of the spectral index towards the outer edges of the lobes. The spectral index of the lobes is $\alpha^{609}_{140} \sim -1$ and gradually steepens to $\alpha^{609}_{140} \sim -1.8$ moving towards the inner edges of the lobes. Using radiative ageing model fitting we show that the AGN activity ceased around 50 Myr ago. We note that the outer regions of the lobes are younger than the inner regions which is interpreted as a sign that those regions are remnant hotspots. We demonstrate the usefulness of maps of AGN radio remnants taken at low frequencies and suggest caution over the interpretation of spectral ages derived from integrated flux density measurements versus age mapping. The spectral index properties as well as the derived ages of B2 0924+30 are consistent with it being an FRII AGN radio remnant. LOFAR data are proving to be instrumental in extending our studies to the lowest radio frequencies and enabling analysis of the oldest source regions

Polarized point sources in the LOFAR Two-meter Sky Survey: A preliminary catalog

The polarization properties of radio sources at very low frequencies (<200 MHz) have not been widely measured, but the new generation of low-frequency radio telescopes, including the Low Frequency Array (LOFAR: a Square Kilometre Array Low pathfinder), now gives us the opportunity to investigate these properties. In this paper, we report on the preliminary development of a data reduction pipeline to carry out polarization processing and Faraday tomography for data from the LOFAR Two-meter Sky Survey (LOTSS) and present the results of this pipeline from the LOTSS preliminary data release region (10h45m - 15h30m right ascension, 45 - 57 degrees declination, 570 square degrees). We have produced a catalog of 92 polarized radio sources at 150 MHz at 4.3 arcminute resolution and 1 mJy rms sensitivity, which is the largest catalog of polarized sources at such low frequencies. We estimate a lower limit to the polarized source surface density at 150 MHz, with our resolution and sensitivity, of 1 source per 6.2 square degrees. We find that our Faraday depth measurements are in agreement with previous measurements and have significantly smaller errors. Most of our sources show significant depolarization compared to 1.4 GHz, but there is a small population of sources with low depolarization indicating that their polarized emission is highly localized in Faraday depth. We predict that an extension of this work to the full LOTSS data would detect at least 3400 polarized sources using the same methods, and probably considerably more with improved data processing.Comment: 20 pages, 8 figures, 2 catalog tables (non-machine readable), accepted for publication in A&

Predicting climate change impacts on polar bear litter size

Predicting the ecological impacts of climate warming is critical for species conservation. Incorporating future warming into population models, however, is challenging because reproduction and survival cannot be measured for yet unobserved environmental conditions. In this study, we use mechanistic energy budget models and data obtainable under current conditions to predict polar bear litter size under future conditions. In western Hudson Bay, we predict climate warming-induced litter size declines that jeopardize population viability: ∼28% of pregnant females failed to reproduce for energetic reasons during the early 1990s, but 40–73% could fail if spring sea ice break-up occurs 1 month earlier than during the 1990s, and 55–100% if break-up occurs 2 months earlier. Simultaneously, mean litter size would decrease by 22–67% and 44–100%, respectively. The expected timeline for these declines varies with climate-model-specific sea ice predictions. Similar litter size declines may occur in over one-third of the global polar bear population