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Choline plays a crucial role in lipid metabolism for fish, and its deficiency in aquafeed has been linked to compromised health and growth performance. A 56-d experiment was conducted to examine the effects of dietary choline on lipid composition, histology and plasma biochemistry of yellowtail kingfish (Seriola lalandi; YTK; 156 g initial body weight). The dietary choline content ranged from 0·59 to 6·22 g/kg diet. 2-Amino-2-methyl-1-propanol (AMP) (3 g/kg) was added to diets, except for a control diet, to limit de novo choline synthesis. The results showed that the liver lipid content of YTK was similar among diets containing AMP and dominated by NEFA. In contrast, fish fed the control diet had significantly elevated liver TAG. Generally, the SFA, MUFA and PUFA content of liver lipid in fish fed diets containing AMP was not influenced by choline content. The SFA and MUFA content of liver lipid in fish fed the control diet was similar to other diets except for a decrease in PUFA. The linear relationship between lipid digestibility and plasma cholesterol was significant, otherwise most parameters were unaffected. When AMP is present, higher dietary choline reduced the severity of some hepatic lesions. The present study demonstrated that choline deficiency affects some plasma and liver histology parameters in juvenile YTK which might be useful fish health indicators. Importantly, the present study elucidated potential reasons for lower growth in choline-deficient YTK and increased the knowledge on choline metabolism in the fish.
The International Personality Item Pool (IPIP) five-factor model inventories are widely used for personality research and have been translated into multiple languages. However, the extent of the psychometric assessment of translated scales is variable, often minimal. The lack of psychometric scrutiny is particularly problematic because translation is an inherently complex process. Here, we present a structural analysis of one Spanish translation of the 50-item IPIP five-factor inventory in a sample of Peruvian, non-university educated, working adults (n = 778). A global confirmatory factor analytic (CFA) model of the a priori five factors failed to fit. So too did single factor models for four of the five factors, the exception being Neuroticism. Fit was improved via use of an exploratory structural equation measurement model, but the resultant solution showed very poor theoretical coherence. So, we explored the data for systematic measurement artefacts and sought to model them to improve the psychometric properties of the scale. Specifically, the pattern of factor loadings suggested that the lack of coherence might be due to the effects of the valence of item wording (i.e., positively or negatively worded items). CFA models including five substantive factors and a series of method factors modelling shared covariance based on item wording, improved fit and coherence. This investigation suggests that unless method factors are explicitly modelled the tested Spanish translation may not be suitable for use in certain Spanish-speaking countries or samples composed of non-university educated participants. More broadly, the study has implications for many translated scales, especially when used without thorough psychometric evaluation.
While the Victorian ideal of the public park is well understood, we know less of how local governors sought to realize this ideal in practice. This article is concerned with park-making as a process – contingent, unstable, open – rather than with parks as outcomes – determined, settled, closed. It details how local governors bounded, designed and regulated park spaces to differentiate them as ‘spaces apart’ within the city, and how this programme of spatial governance was obstructed, frustrated and diverted by political, environmental and social forces. The article also uses this historical analysis to provide a new perspective on the future prospects of urban parks today.
In a context of hyper-diversity and social polarisation, it has been suggested that public parks constitute crucial arenas in which to safeguard deliberative democracy and foster social relations that bind loosely connected strangers. Drawing on empirical research, we offer a more circumspect and nuanced understanding of the – nonetheless vital – role that parks can play in fostering civic norms that support the capacity for living with difference. As ‘spaces apart’, parks have distinctive atmospheres that afford opportunities for convivial encounters in which ‘indifference to difference’ underpins ‘openness to otherness’. As places in which difference is rendered routine and unremarkable, the potency of parks for social cohesion derives from fleeting and unanticipated interactions and the weak ties they promote, rather than strong bonds of community that tend to solidify lines of cultural differentiation. Both by design and unintentionally, regulation and law can serve to foster or constrain the conditions that sustain conviviality.
Make recommendations on approaches to building and strengthening relationships between academic departments or divisions of Emergency Medicine and rural and regional emergency departments.
Methods
A panel of leaders from both rural and urban/academic practice environments met over 8 months. Draft recommendations were developed from panel expertise as well as survey data and presented at the 2018 Canadian Association of Emergency Physicians (CAEP) Academic Symposium. Symposium feedback was incorporated into final recommendations.
Results
Seven recommendations emerged and are summarized below:
1) CAEP should ensure engagement with other rural stakeholder organizations such as the College of Family Physicians of Canada and the Society of Rural Physicians of Canada.
2) Engagement efforts require adequate financial and manpower resources.
3) Training opportunities should be promoted.
4) The current operational interface between the academic department of Emergency Medicine and the emergency departments in the catchment area must be examined and gaps addressed as part of building and strengthening relationships.
5) Initial engagement efforts should be around projects with common value.
6) Academic Departments should partner with and support rural scholars.
7) Academic departments seeking to build or strengthen relationships should consider successful examples from elsewhere in the country as well as considering local culture and challenges.
Conclusion
These recommendations serve as guidance for building and strengthening mutually beneficial relationships between academic departments or divisions of Emergency Medicine and rural and regional emergency departments.
Suboptimality of decision making needs no explanation. High-level accounts of suboptimality in diverse tasks cannot add up to a mechanistic theory of perceptual decision making. Mental processes operate on the contents of information brought by the experimenter and the participant to the task, not on the amount of information in the stimuli without regard to physical and social context.
Decision-makers are increasingly recognizing the usefulness of qualitative research to inform patient-centered policy decisions, and are accordingly increasingly demanding qualitative evidence as part of health technology assessment (HTA). In the context of tight HTA timelines, a new form of evidence synthesis has emerged—rapid qualitative reviews. The need for rapidity requires either an increase in resources or, more commonly, a compromise in rigor, yet guidance on appropriate compromises for qualitative reviews is lacking.
Methods:
In order to inform de novo guidance, we conducted a systematic scoping review to identify existing guidance and published examples of rapid qualitative reviews. We searched Medline and CINAHL using medical subject headings and keywords related to “rapid reviews” and “qualitative” research, and screened the 1,771 resultant citations independently in duplicate. Additionally, we searched the grey literature and solicited examples from our contacts and other evidence-synthesis organizations. We summarized included guidance and reviews using the Search, AppraisaL, Synthesis, Analysis (SALSA) framework to identify abbreviations in the review process.
Results:
We found no guidance documents specific to rapid qualitative reviews. We found one published peer-reviewed rapid qualitative review, and several more (>10; grey literature search in process) through our organizational contacts. While methods to abbreviate the process are poorly reported, an abbreviated literature search (years and databases searched) and the use of a single reviewer appear common.
Conclusions:
A number of agencies are producing rapid qualitative reviews, however our review identifies the urgent need to develop and explore methods for the synthesis of qualitative research that balance rapidity and rigor.
The role that vitamin D plays in pulmonary function remains uncertain. Epidemiological studies reported mixed findings for serum 25-hydroxyvitamin D (25(OH)D)–pulmonary function association. We conducted the largest cross-sectional meta-analysis of the 25(OH)D–pulmonary function association to date, based on nine European ancestry (EA) cohorts (n 22 838) and five African ancestry (AA) cohorts (n 4290) in the Cohorts for Heart and Aging Research in Genomic Epidemiology Consortium. Data were analysed using linear models by cohort and ancestry. Effect modification by smoking status (current/former/never) was tested. Results were combined using fixed-effects meta-analysis. Mean serum 25(OH)D was 68 (sd 29) nmol/l for EA and 49 (sd 21) nmol/l for AA. For each 1 nmol/l higher 25(OH)D, forced expiratory volume in the 1st second (FEV1) was higher by 1·1 ml in EA (95 % CI 0·9, 1·3; P<0·0001) and 1·8 ml (95 % CI 1·1, 2·5; P<0·0001) in AA (Prace difference=0·06), and forced vital capacity (FVC) was higher by 1·3 ml in EA (95 % CI 1·0, 1·6; P<0·0001) and 1·5 ml (95 % CI 0·8, 2·3; P=0·0001) in AA (Prace difference=0·56). Among EA, the 25(OH)D–FVC association was stronger in smokers: per 1 nmol/l higher 25(OH)D, FVC was higher by 1·7 ml (95 % CI 1·1, 2·3) for current smokers and 1·7 ml (95 % CI 1·2, 2·1) for former smokers, compared with 0·8 ml (95 % CI 0·4, 1·2) for never smokers. In summary, the 25(OH)D associations with FEV1 and FVC were positive in both ancestries. In EA, a stronger association was observed for smokers compared with never smokers, which supports the importance of vitamin D in vulnerable populations.
Some individuals have a neurogenetic vulnerability to developing strong facilitation of ingestive movements by learned configurations of biosocial stimuli. Condemning food as addictive is mere polemic, ignoring the contextualised sensory control of the mastication of each mouthful. To beat obesity, the least fattening of widely recognised eating patterns needs to be measured and supported.
Conservation tillage systems, such as no-tillage, are ecologically advantageous because they reduce soil erosion; however, they rely heavily on herbicide use. Our goal was to determine how weed communities of no-tillage systems are affected when the system is modified to reduce herbicide use through a combination of banded herbicides and interrow cultivation. To this end, we conducted a 9-yr study in a no-tillage corn–soybean–winter wheat rotation. All management systems had a preplant application of glyphosate, followed by either broadcast PRE herbicides (conventional no-tillage), interrow cultivation with banded PRE herbicides, or interrow cultivation alone. Aboveground weed densities were assessed each year and data were grouped into early (1991 to 1993) and late (1996 to 1998) time periods. Over time, weed communities became more distinct, showing a strong response to management and crop. In the early years, weed communities separated more in response to management than crop. In the late years, this was reversed. Weed communities in systems with interrow cultivation were more diverse than those in conventional no-tillage. The response to weed management system and crop was species specific. For example, the abundance of yellow foxtail was higher when interrow cultivation was employed, but abundance was equal in all crops. Dandelion was more abundant in conventional no-tillage of corn and soybean; however, it was equally abundant in all management systems in wheat. Seed bank species richness increased over time and was highest in systems with interrow cultivation. Herbicide use can be reduced in a modified no-tillage corn–soybean–wheat rotation by incorporating interrow cultivation, with or without banded herbicides, into the management plan. The weed community trajectory changes, and the weed community becomes more diverse. A more diverse weed community will not necessarily alter how we manage weeds.
This study investigated factors that influence occurrence and persistence of plant DNA in the soil environment in three crop rotations. In each rotation, soil was sampled in May before planting, in July and August while crops were growing, and in October after harvest. Total DNA was recovered from soil samples taken at two different depths in the soil profile and quantified. Three target plant genes (corn CP4 epsps, corn 10-kD Zein, and soybean CP4 epsps) also were quantified in these DNA extracts using species-specific quantitative real-time PCR assays. In general, total plant DNA content in the soil environment was greatest when the crop was growing in the field and decreased rapidly after harvest. Nevertheless, low levels of target plant DNA were often still detectable the following spring. Age of rotation did not influence target DNA quantities found in the soil environment. Data were collected for a combination of 10 location-years, which allowed for estimation of the variance components for six factors including time of sampling, year, location, crop, sampling depth, and herbicide to total and target DNA content in the soil samples. Mean target recombinant DNA content in soil was influenced most strongly by time of sampling and year (85 and 6%, respectively), whereas total soil DNA content was less dynamic and was most strongly influenced by location and year (49 and 25%, respectively). Over the duration of this study, no accumulation of transgenic plant DNA in the soil environment was observed.
A 9-yr (1990–1998) study was conducted at Woodstock, ON, Canada, to evaluate weed densities, crop yields, and gross returns in a modified no-tillage (no primary tillage) corn–soybean–winter wheat rotation under three weed management treatments: (1) minimum, preplant application of glyphosate followed by mechanical control; (2) integrated weed management (IWM), preplant application of glyphosate followed by band application of preemergence herbicides plus mechanical control; and (3) conventional, preplant application of glyphosate followed by broadcast application of preemergence herbicides in corn and soybean. In wheat the minimum and IWM treatments had no additional weed control measures other than the preplant application of glyphosate, whereas the conventional treatment had a broadcast application of a postemergence herbicide. Weed densities were assessed each year, (except in 1990) once during the growing season in corn and soybean and immediately after crop harvest in wheat. Adjusted gross return was calculated as the gross revenue minus the unique costs for weed control for each of the treatments. Weed densities were greater in the minimum treatment compared with the IWM or conventional treatment in all crops. Weed densities in the IWM and conventional treatments did not differ. There was no apparent “buildup” of weed density with time in the rotation resulting from weed escapes. Hence, these data challenge current thinking that weed densities increase with time if weed escapes are allowed to go to seed. Corn and soybean yields in the IWM and conventional treatments did not differ. However, the minimum treatment had the lowest corn and soybean yields. Winter wheat yield was not affected by the treatments. All weed management treatments provided similar gross returns for each crop and for the rotation. Thus, the minimum treatment consisting of glyphosate applied preplant followed by shallow interrow tillage appeared to be a viable option, especially if practiced in a farming system capable of ensuring adequate timing of cultivation operations.
The collective response of electrons in an ultrathin foil target irradiated by an ultraintense (${\sim}6\times 10^{20}~\text{W}~\text{cm}^{-2}$) laser pulse is investigated experimentally and via 3D particle-in-cell simulations. It is shown that if the target is sufficiently thin that the laser induces significant radiation pressure, but not thin enough to become relativistically transparent to the laser light, the resulting relativistic electron beam is elliptical, with the major axis of the ellipse directed along the laser polarization axis. When the target thickness is decreased such that it becomes relativistically transparent early in the interaction with the laser pulse, diffraction of the transmitted laser light occurs through a so called ‘relativistic plasma aperture’, inducing structure in the spatial-intensity profile of the beam of energetic electrons. It is shown that the electron beam profile can be modified by variation of the target thickness and degree of ellipticity in the laser polarization.
Among dialysis facilities participating in a bloodstream infection (BSI) prevention collaborative, access-related BSI incidence rate improvements observed immediately following implementation of a bundle of BSI prevention interventions were sustained for up to 4 years. Overall, BSI incidence remained unchanged from baseline in the current analysis.
The measured spatial-intensity distribution of the beam of protons accelerated from the rear side of a solid target irradiated by an intense (>1019 Wcm−2) laser pulse provides a diagnostic of the two-dimensional fast electron density profile at the target rear surface and thus the fast electron beam transport pattern within the target. An analytical model is developed, accounting for rear-surface fast electron sheath dynamics, ionization and projection of the resulting beam of protons. The sensitivity of the spatial-intensity distribution of the proton beam to the fast electron density distribution is investigated. An annular fast electron beam transport pattern with filamentary structure is inferred for the case of a thick diamond target irradiated at a peak laser intensity of 6 × 1019 Wcm−2.
Using photometry at just two wavelengths it is possible to fit a blackbody to the spectrum of infrared excess that is the signature of a debris disc. From this the location of the dust can be inferred. However, it is well known that dust in debris discs is not a perfect blackbody. By resolving debris discs we can find the actual location of the dust and compare this to that inferred from the blackbody fit. Using the Herschel Space Observatory we resolved many systems as part of the DEBRIS survey. Here we discuss a sample of 9 discs surrounding A stars and find that the discs are actually located between 1 and 2.5 times further from their star than predicted by blackbody fits to the spectral energy distribution (SED). The variation in this ratio is due to differences in stellar luminosities, location of the dust, size distribution and composition of the dust.
It is now widely recognized that a decentralized approach to the control of parasitic infections in rural sub-Saharan populations allows for the design of more effective control programmes and encourages high compliance. Compliance is usually an indicator of treatment success, but cannot be used as a measure of long-term benefit since re-infection will be strongly influenced by a number of factors including the social ecology of a community. In this paper qualitative and quantitative methods are used to identify and understand the structural and behavioural constraints that may influence water contact behaviour and create inequalities with respect to Schistosoma re-infection following anti-helminth drug treatment. The research is set in a community where participant engagement has remained uniformly high throughout the course of a 10-year multidisciplinary study on treatment and re-infection, but where levels of re-infection have not been uniform and, because of variations in water contact behaviour, have varied by age, sex and ethnic background. Variations in the biomedical knowledge of schistosomiasis, socioeconomic constraints and ethnic differences in general attitudes towards life and health are identified that may account for some of these behavioural differences. The observations highlight the benefits of understanding the socio-ecology of control and research settings at several levels (both between and within ethnic groups); this will help to design more effective and universally beneficial interventions for control and help to interpret research findings.
A discrete subaortic membrane cannot only cause left ventricular outflow tract obstruction, but can grow onto the aortic valve leaflets. The late finding of this encroachment is aortic valve insufficiency or stenosis. Echocardiography is used to follow the progression of outflow tract obstruction, but its ability to show subaortic membrane encroachment onto the aortic valve is unclear. The purpose of this study is to determine the sensitivity and specificity of echocardiography for diagnosing whether a discrete subaortic membrane involves the aortic valve.
Methods
A pre-operative determination of aortic valve involvement by a discrete subaortic membrane was obtained by review of the official pre-operative echocardiogram reading and a retrospective blinded review of the pre-operative echocardiogram by an independent echocardiographer. These findings were compared to the intra-operative findings.
Results
A total of 48 consecutive patients underwent primary resection for isolated discrete subaortic membrane between October, 1995 and May, 2006. The pre-operative and blinded readings both predicted a statistically lower rate of aortic valve involvement – 35% in 11 of 31 patients and 31% in 10 of 31 patients, respectively – than found at surgery – 65% in 31 of 48 patients. The sensitivity and specificity of pre-operative echocardiography to diagnose aortic valve involvement is 35% and 76%. Overall survival was 100%. There were no strokes, re-operations for bleeding or wound infections, or need for a pacemaker.
Conclusion
Echocardiography is not sensitive in assessing whether a discrete subaortic membrane involves the aortic valve. Since the morbidity and mortality for discrete subaortic membrane resection is negligible, resection may be indicated at the time of diagnosis to minimise aortic valve impairment.