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The objectives of this paper are to: (1) identify contextual factors such as policy that impacted the implementation of community-based primary health care (CBPHC) innovations among 12 Canadian research teams and (2) describe strategies used by the teams to address contextual factors influencing implementation of CBPHC innovations. In primary care settings, consideration of contextual factors when implementing change has been recognized as critically important to success. However, contextual factors are rarely recorded, analyzed or considered when implementing change. The lack of consideration of contextual factors has negative implications not only for successfully implementing primary health care (PHC) innovations, but also for their sustainability and scalability. For this evaluation, data collection was conducted using self-administered questionnaires and follow-up telephone interviews with team representatives. We used a combination of directed and conventional content analysis approaches to analyze the questionnaire and interview data. Representatives from all 12 teams completed the questionnaire and 11 teams participated in the interviews; 40 individuals participated in this evaluation. Four themes representing contextual factors that impacted the implementation of CBPHC innovations were identified: (I) diversity of jurisdictions (II) complexity of interactions and collaborations (III) policy, and (IV) the multifaceted nature of PHC. The teams used six strategies to address these contextual factors including: (1) conduct an environmental scan at the beginning (2) maintaining engagement among partners and stakeholders by encouraging open and inclusive communication; (3) contextualizing the innovation for different settings; (4) anticipating and addressing changes, delays, and the need for additional resources; (5) fostering a culture of research and innovation among partners and stakeholders; and (6) ensuring information about the innovation is widely available. Implementing CBPHC innovations across jurisdictions is complex and involves navigating through multiple contextual factors. Awareness of the dynamic nature of context should be considered when implementing innovations.
Family-based strategies to reduce the risk of overweight in childhood are needed in the Caribbean.
To investigate the associations between parental characteristics and risk of overweight and explore possible mechanisms.
Data from a parenting intervention were analysed. Parental characteristics were obtained by questionnaire at enrolment. At 18 months, 501 infants (82.9% of cohort) had weight and length measured using standardized methods. The association of parents’ characteristics with risk of infant overweight was assessed using random-effects logistic regression. Four focus groups among mothers in Jamaica were conducted to explore mechanisms.
Overall, 20.6% of infants were ‘at risk of overweight’. Fathers were present in 52% of households. Fathers’ presence [OR (95% CI) 0.60 (0.37–0.96)] was associated with reduced risk of overweight independent of socioeconomic status. Mothers reported that fathers encouraged healthier practices.
Fathers may be important agents of change in intervention strategies to prevent childhood overweight.
Knowledge of the effects of burial depth and burial duration on seed viability and, consequently, seedbank persistence of Palmer amaranth (Amaranthus palmeri S. Watson) and waterhemp [Amaranthus tuberculatus (Moq.) J. D. Sauer] ecotypes can be used for the development of efficient weed management programs. This is of particular interest, given the great fecundity of both species and, consequently, their high seedbank replenishment potential. Seeds of both species collected from five different locations across the United States were investigated in seven states (sites) with different soil and climatic conditions. Seeds were placed at two depths (0 and 15 cm) for 3 yr. Each year, seeds were retrieved, and seed damage (shrunken, malformed, or broken) plus losses (deteriorated and futile germination) and viability were evaluated. Greater seed damage plus loss averaged across seed origin, burial depth, and year was recorded for lots tested at Illinois (51.3% and 51.8%) followed by Tennessee (40.5% and 45.1%) and Missouri (39.2% and 42%) for A. palmeri and A. tuberculatus, respectively. The site differences for seed persistence were probably due to higher volumetric water content at these sites. Rates of seed demise were directly proportional to burial depth (α=0.001), whereas the percentage of viable seeds recovered after 36 mo on the soil surface ranged from 4.1% to 4.3% compared with 5% to 5.3% at the 15-cm depth for A. palmeri and A. tuberculatus, respectively. Seed viability loss was greater in the seeds placed on the soil surface compared with the buried seeds. The greatest influences on seed viability were burial conditions and time and site-specific soil conditions, more so than geographical location. Thus, management of these weed species should focus on reducing seed shattering, enhancing seed removal from the soil surface, or adjusting tillage systems.
We examined risk factors associated with the intestinal acquisition of antimicrobial-resistant extraintestinal pathogenic Escherichia coli (ExPEC) and development of community-acquired urinary tract infection (UTI) in a case-control study of young women across Canada. A total of 399 women were recruited; 164 women had a UTI caused by E. coli resistant to ⩾1 antimicrobial classes and 98 had a UTI caused by E. coli resistant to ⩾3 antimicrobial classes. After adjustment for age, student health service (region of Canada) and either prior antibiotic use or UTI history, consumption of processed or ground chicken, cooked or raw shellfish, street foods and any organic fruit; as well as, contact with chickens, dogs and pet treats; and travel to Asia, were associated with an increased risk of UTI caused by antimicrobial resistant E. coli. A decreased risk of antimicrobial resistant UTI was associated with consumption of apples, nectarines, peppers, fresh herbs, peanuts and cooked beef. Drug-resistant UTI linked to foodborne and environmental exposures may be a significant public health concern and understanding the risk factors for intestinal acquisition of existing or newly emerging lineages of drug-resistant ExPEC is important for epidemiology, antimicrobial stewardship and prevention efforts.
We present Kitty, an unprecedented and near simultaneous flaring event in ten transitions (6 hydroxyl, 1 water and 3 methanol), that began on 1 January 2015 in the massive star-forming region NGC6334F located in the Cat’s Paw Nebula. The brightest components in each transition increased by factors of 20 to 70 in line with a factor of ~70 increase in dust emission luminosity for the source MM1. We also report the detection of only the fifth known 4.660 GHz hydroxyl maser and that it varied in a correlated fashion with 1.720, 6.031, and 6.035 GHz hydroxyl counterparts. We postulate that if Kitty, and two historical flares in 1965 & 1999, are accretion events and are caused by the successive passages of a secondary star disrupting the accretion disk, where the frequency of occurrence is cycling down at a rate of ~2.2, it is possible another event will occur in 2022.
We report progress on research relating to 36.2 GHz extragalactic class I methanol masers, including a review of published work and new observations at high angular resolution. These observations reveal that extragalactic class I masers are excited in shocked gas and maybe associated with starbursts, galactic-scale outflows from active galactic nuclei (AGNs) feedback, or the inner-end region of the galactic bar. The current observational results suggests that extragalactic class I methanol masers provide a new probe for starbursts and feedback in active galaxies.
Ring−like sources of 6.7 GHz methanol maser emission were discovered a decade ago with the European VLBI Network. In the past years we have been incessantly working to understand the nature of these rings. In general, the methanol rings do not coincide with H II regions nor they show 22 GHz water maser emission. Here, we present a proper motion study over a time baseline up to 10.5 years for the first sub-sample of methanol maser rings. Our findings suggest that in three targets G23.207−00.377, G23.389+00.185, and G23.657−00.127, such rings form in outflows or even in winds close to the central sources, and the masers trace slow proper motions of a few km s−1 typically.
We present observational results of the submillimeter H2O and SiO lines toward a candidate high-mass young stellar object Orion Source I using ALMA. The spatial structures of the high excitation lines at lower-state energies of >2500 K show compact structures consistent with the circumstellar disk and/or base of the northeast-southwest bipolar outflow with a 100 au scale. The highest excitation transition, the SiO (v=4) line at band 8, has the most compact structure. In contrast, lower-excitation transitions are more extended than 200 au tracing the outflow. Almost all the line show velocity gradients perpendicular to the outflow axis suggesting rotation motions of the circumstellar disk and outflow. While some of the detected lines show broad line profiles and spatially extended emission components indicative of thermal excitation, the strong H2O lines at 321 GHz, 474 GHz, and 658 GHz with brightness temperatures of >1000 K show clear signatures of maser action.
Disk megamasers are a unique tool to study active galactic nuclei (AGN) sub-pc environment, and precisely measure some of their fundamental parameters. While the majority of disk megamasers are hosted in heavily obscured (i.e., Seyfert 2, Sy2) AGN, the converse is not true, and disk megamasers are very rarely found even in obscured AGN. The very low detection rate of such systems in Sy2 AGN could be due to the geometry of the maser beaming, which requires a strict edge-on condition. We explore some other fundamental factors which could play a role in a volume-limited survey of disk megamasers in Sy2 galaxies, most importantly the radio luminosity.
We summarize a long-term monitoring of 11 periodic 6.7 GHz methanol masers and a search for new periodic sources. Observations were carried out with the Torun 32 m telescope. Periods of observed sources range from 29 to 658 days and the data consist of more than 10 observed cycles for most of the masers. Inspection of archival data resulted in identification of 3 new periodic sources while 2 new periodic objects were found in observations started in 2014.
The interferometric and single-dish observations of the Extended Green Objects sample have been carried out in order to check the possible common pumping mechanism of class I methanol maser (cIMM) and OH(1720 MHz) maser and their identification with a front of bipolar outflow as a source of interstellar shock stimulating collisional pumping of the molecules. High spatial and spectral resolution observations of OH masers allow us to investigate structure, kinematics, and magnetic field configuration of the inner region of the source, i.e., the outflow ejection region. Analysis of magnetic field strength in a disk area is crucial to understanding of the outflow origin.
Charles Malcolm Walmsley passed away on 1 May 2017. Over a long and highly productive career, Malcolm made numerous and fundamental contributions to the science of the interstellar medium and star formation. These have recently been summarized elsewhere (Menten & Cesaroni 2017). Here I would like to describe some of his work related to masers.
Methanol masers observed at high angular resolution are useful tool to investigate the processes of high-mass star formation. Here, we present the results of statistical analysis of the 6.7 GHz methanol maser structures in 60 sources observed with the EVN. The parameters of the maser clouds and exciting stars were derived. There is evidence that the emission structures composed of larger number of maser clouds are formed in the vicinity of more luminous exciting stars.
The Square Kilometre Array (SKA), reaching a collecting area of one square kilometre, will be the world’s largest radio telescope. Even in its first stage of deployment (SKA1, whose construction will be completed in 2026) it will enable transformational science on a very broad range of scientific objectives. Amongst them, there is the investigation of several Galactic and extra-galactic Masers. In this paper I will present the status of the SKA project and I will describe the capabilities of the SKA, with a focus on those that are more relevant for Maser science.
We report the discovery of widespread millimeter-wavelength Class I methanol maser emission associated with protostellar molecular outflows in the massive (proto)cluster G11.92−0.61. Our ~0.5″-resolution SMA and ALMA observations of the 229 GHz and 278 GHz Class I transitions reveal seven and twelve candidate masers, respectively: all 229 GHz masers have 278 GHz counterparts, and five are also coincident with 44 GHz Class I masers previously detected with the VLA. For paired masers, the peak intensities at 229 GHz and 278 GHz are correlated. We also find tentative evidence for a correlation between the strength of millimeter-wavelength Class I maser emission and the energy of the associated molecular outflow.
Circumstellar SiO masers can be observed in red giant evolved stars throughout the Galaxy. Since stellar masers are not affected by non-gravitational forces, they serve as point-mass probes of the gravitational potential and form an excellent sample for studies of the Galactic structure and dynamics. Compared to optical studies, the non-obscured masers are in particular valuable when observed close to the highly obscured Galactic Bulge and Plane. Their line-of-sight velocities can easily be obtained with high accuracy, proper motions can be measured and distances can be estimated. Furthermore, when different mass and metallicity effects can be accounted for, such a large sample will highlight asymmetries and evolutionary traces in the sample. In our Bulge Asymmetries and Dynamic Evolution (BAaDE) survey we have searched 20,000 infrared selected evolved stars for 43 GHz SiO masers with the VLA in the northern Bulge and Plane and are in the process of observing another 10,000 stars for 86 GHz SiO masers with ALMA in the southern Bulge. Our instantaneous detection rate in the Bulge is close to 70%, both at 43 and 86 GHz, with occasionally up to 7 simultaneous SiO transitions observed in a single star. Here we will outline the BAaDE survey, its first results and some of the peculiar maser features we have observed. Furthermore we will discuss the prospects for obtaining proper motions and parallaxes for individual maser stars to reconstruct individual stellar orbits.
Ventspils International Radio Astronomy Centre (VIRAC) has two fully steerable Cassegrean System 32 and 16 m radio telescopes. After renovation and modernization program the Galactic masers, particularly CH3OH research and monitoring program became one of the most important realized on these telescopes. Both telescopes are equipped with broadband cryogenic receivers covering 4.5-8.8 GHz frequency band. Digital backend consisting from DBBC-2 (Digital Base Band Convertor developed by HAT-LAB, Italy) and FLEXBUFF (data storage system based on commercially available server system) is used for data digitalization and registration. A special program complex for spectral line data reduction and correction was developed and implemented.
The detection of hydrogen radio-recombination maser lines (RRLs) toward MWC349A in the year 1989 opened the chance to place constraints on the kinematics of an ionized circumstellar disk around a massive star. Since then, a significant number of observations have allowed improving our understanding of this source to the point that we have established that its ionized wind launching occurs at a distance of ~24 au as claimed by disk wind models. On the other hand, this field of study has undergone considerable development over the last six years with the detection of new RRL maser sources. Here, we present a brief summary of all these recent advances and the promising future prospects.
Studies of Galactic LPVs based on astrometric VLBI are presented. We use a VLBI array, “VERA”, to measure parallaxes and calibrate the K-band period luminosity relation (PLR) of the Galactic Miras. Since the PLR offers a distance indicator, its calibration is crucial to reveal their spatial distribution. Parallaxes of dozens of LPVs are presented. For the longer period stars, the mass-loss is high and the stars are obscured and recognized as OH/IR stars. We estimated mid-infrared absolute magnitudes of dozens of OH/IR stars and found that they show a loose concentration around −14 mag at λ of 11.6 μm, indicating an existence of PLR for OH/IR stars. Astrometry of OH/IR stars will also help us to study non-steady spiral arms as proposed from the latest simulation study of the galactic dynamics. We will start astrometric VLBI observation of two OH/IR stars NSV25875 and OH127.8+0.0 at 43 GHz with VERA.
Using quasi-simultaneous observations of 86 stars with known SiO maser emission, we searched for systematic differences between the strengths of the 43 and 86 GHz v=1 maser lines. Although for individual stars there is wide scatter between the line strengths spanning nearly an order of magnitude, there is no evidence of a systematic difference between these line strengths for the entire sample.