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We present a detailed overview of the cosmological surveys that we aim to carry out with Phase 1 of the Square Kilometre Array (SKA1) and the science that they will enable. We highlight three main surveys: a medium-deep continuum weak lensing and low-redshift spectroscopic HI galaxy survey over 5 000 deg2; a wide and deep continuum galaxy and HI intensity mapping (IM) survey over 20 000 deg2 from
$z = 0.35$
to 3; and a deep, high-redshift HI IM survey over 100 deg2 from
$z = 3$
to 6. Taken together, these surveys will achieve an array of important scientific goals: measuring the equation of state of dark energy out to
$z \sim 3$
with percent-level precision measurements of the cosmic expansion rate; constraining possible deviations from General Relativity on cosmological scales by measuring the growth rate of structure through multiple independent methods; mapping the structure of the Universe on the largest accessible scales, thus constraining fundamental properties such as isotropy, homogeneity, and non-Gaussianity; and measuring the HI density and bias out to
$z = 6$
. These surveys will also provide highly complementary clustering and weak lensing measurements that have independent systematic uncertainties to those of optical and near-infrared (NIR) surveys like Euclid, LSST, and WFIRST leading to a multitude of synergies that can improve constraints significantly beyond what optical or radio surveys can achieve on their own. This document, the 2018 Red Book, provides reference technical specifications, cosmological parameter forecasts, and an overview of relevant systematic effects for the three key surveys and will be regularly updated by the Cosmology Science Working Group in the run up to start of operations and the Key Science Programme of SKA1.
Borderline personality disorder (BPD) is a severe and complex disorder characterized by instability across many life domains, including interpersonal relations, behavior, and emotions. A core feature and contributor to BPD, emotion dysegulation (ED), consists of deficits in the ability to regulate emotions in a manner that allows the individual to pursue important goals or behave effectively in various contexts. Biosocial developmental models of BPD have emphasized a transaction of environmental conditions (e.g., invalidating environments and adverse childhood experiences) with key genetically linked vulnerabilities (e.g., impulsivity and emotional vulnerability) in the development of ED and BPD. Emerging evidence has begun to highlight the complex, heterotypic pathways to the development of BPD, with key heritable vulnerability factors possibly interacting with aspects of the rearing environment to produce worsening ED and an adolescent trajectory consisting of self-damaging behaviors and eventual BPD. Adults with BPD have shown evidence of a variety of cognitive, physiological, and behavioral characteristics of ED. As the precursors to the development of ED and BPD have become clearer, prevention and treatment efforts hold great promise for reducing the long-term suffering, functional impairment, and considerable societal costs associated with BPD.
Declining mortality following invasive pneumococcal disease (IPD) has been observed concurrent with a reduced incidence due to effective pneumococcal conjugate vaccines. However, with IPD now increasing due to serotype replacement, we undertook a statistical analysis to estimate the trend in all-cause 30-day case fatality rate (CFR) in the North East of England (NEE) following IPD. Clinical, microbiological and demographic data were obtained for all laboratory-confirmed IPD cases (April 2006–March 2016) and the adjusted association between CFR and epidemiological year estimated using logistic regression. Of the 2510 episodes of IPD included in the analysis, 486 died within 30 days of IPD (CFR 19%). Increasing age, male sex, a diagnosis of septicaemia, being in ⩾1 clinical risk groups, alcohol abuse and individual serotypes were independently associated with increased CFR. A significant decline in CFR over time was observed following adjustment for these significant predictors (adjusted odds ratio 0.93, 95% confidence interval 0.89–0.98; P = 0.003). A small but significant decline in 30-day all-cause CFR following IPD has been observed in the NEE. Nonetheless, certain population groups remain at increased risk of dying following IPD. Despite the introduction of effective vaccines, further strategies to reduce the ongoing burden of mortality from IPD are needed.
Emotion regulation dysfunction is characteristic of psychotic disorders, but little is known about how the use of specific types of emotion regulation strategies differs across phases of psychotic illness. This information is vital for understanding factors contributing to psychosis vulnerability states and developing targeted treatments. Three studies were conducted to examine emotion regulation across phases of psychosis, which included (a) adolescent community members with psychotic-like experiences (PLEs; n = 262) and adolescents without PLEs (n = 1,226); (b) adolescents who met clinical high-risk criteria for a prodromal syndrome (n = 29) and healthy controls (n = 29); and (c) outpatients diagnosed with schizophrenia or schizoaffective disorder (SZ; n = 61) and healthy controls (n = 67). In each study, participants completed the Emotion Regulation Questionnaire and measures of psychiatric symptoms and functional outcome. The three psychosis groups did not differ from each other in reported use of suppression; however, there was evidence for a vulnerability-related, dose-dependent decrease in reappraisal. Across each sample, a lower use of reappraisal was associated with poorer clinical outcomes. Findings indicate that emotion regulation abnormalities occur across a continuum of psychosis vulnerability and represent important targets for intervention.
This study examined the comminution of fresh herbage, subsequent nutrient release, and the characteristics of swallowed boli from three physically and chemically contrasting forages during ingestive mastication by dairy cows. The extent and pattern of nutrient release will determine their availability to rumen microflora, and potentially influence their efficiency of use. The forages evaluated were perennial ryegrass (ryegrass, Lolium perenne L., cv Alto AR37), lucerne (Medicago sativa L., cv Torlesse) and chicory (Cichorium intybus L., cv Choice). Experimental design was a 3×3 cross-over with three forages and three consecutive 1-day measurement periods, conducted twice. Six non-lactating, pregnant, multiparous Holstein-Friesian×Jersey cows (Bos taurus) were used, with the first cross-over applied to three mature (10.1±0.61 years old; BW 631±64 kg) cows, and the second to three young (4.8±0.02 years; BW 505±19 kg) cows. Fresh cut forage was offered to the cows following partial rumen evacuation. Swallowed boli were collected directly at the cardia at the commencement, middle and end of the first feeding bout of the first meal of the day. Forage species did not affect the fresh weight of ingested boli (mean 169 g, P=0.605) but the proportion of saliva in boli varied between forage. Boli of chicory contained the greatest amount of herbage material and least amount of saliva, whereas ryegrass boli were the opposite. Boli fresh weight tended to increase as time in the meal progressed, but the age of the cow was not shown to affect any boli characteristics or nutrient release. Particle size reduction was affected by forage, with 31%, 38% and 35% of chicory, lucerne and ryegrass herbage reduced to <2 mm. There was little evidence of relationship between comminution and any physical or chemical characteristic of the forage, except in ryegrass where extent of comminution was moderately correlated with herbage strength. Proportional release of herbage soluble carbohydrate exceeded that of N during mastication. Differences in loss of N were moderately correlated with the amount of N in the herbage (R2=0.53) but herbage comminution was not strongly correlated with release of either N or carbohydrate. These findings illustrate the complex animal×forage interactions that occur during mastication, and that it is not possible to infer nutrient loss from herbage based on herbage characteristics as the driver for this differ between species.
One method to grow artificial body tissue is to place a porous scaffold seeded with cells, known as a tissue construct, into a rotating bioreactor filled with a nutrient-rich fluid. The flow within the bioreactor is affected by the movement of the construct relative to the bioreactor which, in turn, is affected by the hydrodynamical and gravitational forces the construct experiences. The construct motion is thus coupled to the flow within the bioreactor. Over the time scale of a few hours, the construct appears to move in a periodic orbit but, over tens of hours, the construct drifts from periodicity. In the biological literature, this effect is often attributed to the change in density of the construct that occurs via tissue growth. In this paper, we show that weak inertia can cause the construct to drift from its periodic orbit over the same time scale as tissue growth. We consider the coupled flow and construct motion problem within a rotating high-aspect-ratio vessel bioreactor. Using an asymptotic analysis, we investigate the case where the Reynolds number is large but the geometry of the bioreactor yields a small reduced Reynolds number, resulting in a weak inertial effect. In particular, to accurately couple the bioreactor and porous flow regions, we extend the nested boundary layer analysis of Dalwadi et al. (J. Fluid Mech., vol. 798, 2016, pp. 88–139) to include moving walls and the thin region between the porous construct and the bioreactor wall. This allows us to derive a closed system of nonlinear ordinary differential equations for the construct trajectory, from which we show that neglecting inertia results in periodic orbits; we solve the inertia-free problem analytically, calculating the periodic orbits in terms of the system parameters. Using a multiple-scale analysis, we then systematically derive a simpler system of nonlinear ordinary differential equations that describe the long-time drift of the construct due to the effect of weak inertia. We investigate the bifurcations of the construct trajectory behaviour, and the limit cycles that appear when the construct is less dense than the surrounding fluid and the rotation rate is large enough. Thus, we are able to predict when the tissue construct will drift towards a stable limit cycle within the bioreactor and when it will drift out until it hits the bioreactor edge.
The aim of this work is to better understand fluid displacement mechanisms at the pore scale in relation to capillary-filling rules. Using specifically designed micro-models we investigate the role of pore body shape on fluid displacement during drainage and imbibition via quasi-static and spontaneous experiments at ambient conditions. The experimental results are directly compared to lattice Boltzmann (LB) simulations. The critical pore-filling pressures for the quasi-static experiments agree well with those predicted by the Young–Laplace equation and follow the expected filling events. However, the spontaneous imbibition experimental results differ from those predicted by the Young–Laplace equation; instead of entering the narrowest available downstream throat the wetting phase enters an adjacent throat first. Thus, pore geometry plays a vital role as it becomes the main deciding factor in the displacement pathways. Current pore network models used to predict displacement at the field scale may need to be revised as they currently use the filling rules proposed by Lenormand et al. (J. Fluid Mech., vol. 135, 1983, pp. 337–353). Energy balance arguments are particularly insightful in understanding the aspects affecting capillary-filling rules. Moreover, simulation results on spontaneous imbibition, in excellent agreement with theoretical predictions, reveal that the capillary number itself is not sufficient to characterise the two phase flow. The Ohnesorge number, which gives the relative importance of viscous forces over inertial and capillary forces, is required to fully describe the fluid flow, along with the viscosity ratio.
The purpose of this paper is to describe factors important for the recruitment and retention of Emergency Medical Technician (EMT)-Basics and EMT-Paramedics new to the Emergency Medical Services (EMS) field (defined as two years or less of EMS employment) through an analysis of 10 years of Longitudinal EMT Attributes and Demographic Study (LEADS) data.
Data were obtained from 10 years of LEADS surveys (1999-2008). Individuals new to the profession were identified through responses to a survey item. Their responses were analyzed using weights reflecting each individual’s probability of selection. Means, proportions, and 95% confidence intervals (CIs) were determined and used to identify statistically significant differences.
There were few changes in the demographic characteristics of new EMT-Basics and Paramedics across survey years. New EMT-Basics tended to be older and less likely to have a college degree than new EMT-Paramedics. More new EMT-Basics than EMT-Paramedics worked in rural areas and small towns and reported that they were working as a volunteer. There were differences between new EMT-Basics and EMT-Paramedics in several of the reasons for entering the profession and in facets of job satisfaction.
The findings provide guidance for recruiters, educators, employers, and governmental EMS policy organizations and will provide better insight into how to attract and retain new entrants to the field.
ChapmanSA, CroweRP, BentleyMA. Recruitment and Retention of New Emergency Medical Technician (EMT)-Basics and Paramedics. Prehosp Disaster Med. 2016;31(Suppl. 1):s70–s86.
Seed-dispersal ecology in tropical montane forests (TMF) differs in some predictable ways from tropical lowland forests (TLF). Environmental, biogeographic and biotic factors together shape dispersal syndromes which in turn influence forest structure and community composition. Data on diaspore traits along five elevational gradients from forests in Thailand, the Philippines, Tanzania, Malawi and Nigeria showed that diaspore size decreases with increasing altitude, fleshy fruits remain the most common fruit type but the relative proportion of wind-dispersed diaspores increases with altitude. Probably corresponding to diaspore size decreasing with increasing elevation, we also provide evidence that avian body size and gape width decrease with increasing altitude. Among other notable changes in the frugivorous fauna across elevational gradients, we found quantitative evidence illustrating that the proportion of bird versus mammalian frugivores increases with altitude, while TMF primates decrease in diversity and density, and switch diets to include less fruit and more leaf proportionately. A paucity of studies on dispersal distance and seed shadows, the dispersal/predation balance and density-dependent mortality thwart much-needed conclusive comparisons of seed dispersal ecology between TMF and TLF, especially from understudied Asian forests. We examine the available evidence, reveal knowledge gaps and recommend research to enhance our understanding of seed dispersal ecology in tropical forests. This review demonstrates that seed dispersal is a more deterministic and important process in tropical montane forests than has been previously appreciated.
Background: There are currently no national standards for clinical electromyography (EMG) training for residents in neurology and physiatry in Canada. The purpose of this study was to obtain demographic and qualitative data pertaining to EMG residency training in Canada, with the goal of facilitating discourse that could lead to national standards for EMG training. Methods: An online survey was distributed to senior neurology and physiatry residents (post-graduate years 3-5), at seven tertiary Canadian centres. The study authors, who are trainees and consultants with a broad range of EMG expertise (junior and senior resident, clinical neuromuscular fellows, senior physiatrist and neuromuscular neurologists), developed pertinent demographic and qualitative questions. Results: Thirty-eight residents completed the survey (23 neurology, 15 physiatry). There was inter-program variation in quantity of the training experience, content of the curriculum, access to expertise (including technologists) and goals for future training and practice. Similarly, differences were identified between the training experiences of neurology and physiatry residents. Conclusions: Inter-program variability in EMG training was identified. Additionally, differences were identified between neurology and physiatry resident training. This data provides evidence of training discrepancies across the country and can be used to establish national training standards for EMG in Canada.
The method of matched asymptotic expansions is used to study the canonical problem of steady laminar flow through a narrow two-dimensional channel blocked by a tight-fitting finite-length highly permeable porous obstacle. We investigate the behaviour of the local flow close to the interface between the single-phase and porous regions (governed by the incompressible Navier–Stokes and Darcy flow equations, respectively). We solve for the flow in these inner regions in the limits of low and high Reynolds number, facilitating an understanding of the nature of the transition from Poiseuille to plug to Poiseuille flow in each of these limits. Significant analytical progress is made in the high Reynolds number limit, and we explore in detail the rich boundary layer structure that occurs. We derive general results for the interfacial stress and for the conditions that couple the flow in the outer regions away from the interface. We consider the three-dimensional generalization to unsteady laminar flow through and around a tight-fitting highly permeable cylindrical porous obstacle within a Hele-Shaw cell. For the high Reynolds number limit, we give the coupling conditions and interfacial stress in terms of the outer flow variables, allowing information from a nonlinear three-dimensional problem to be obtained by solving a linear two-dimensional problem. Finally, we illustrate the utility of our analysis by considering the specific example of time-dependent forced far-field flow in a Hele-Shaw cell containing a porous cylinder with a circular cross-section. We determine the internal stress within the porous obstacle, which is key for tissue engineering applications, and the interfacial stress on the boundary of the porous obstacle, which has applications to biofilm erosion. In the high Reynolds number limit, we demonstrate that the fluid inertia can result in the cylinder experiencing a time-independent net force, even when the far-field forcing is periodic with zero mean.
JET experiments have compared the efficacy of low- and high-field side ion cyclotron resonance heating (ICRH) as an actuator to deliberately minimise the sawtooth period. It is found that low-field side ICRH with low minority concentration is optimal for sawtooth control for two main reasons. Firstly, low-field side heating means that any toroidal phasing of the ICRH (
or dipole) has a destabilising effect on the sawteeth, meaning that dipole phasing can be employed, since this is preferable due to less plasma wall interaction from Resonant Frequency (RF) sheaths. Secondly, the resonance position of the low-field side ICRH does not have to be very accurately placed to achieve sawtooth control, relaxing the requirement for real-time control of the RF frequency. These empirical observations have been confirmed by hybrid kinetic–magnetohydrodynamic modelling, and suggest that the ICRH antenna design for ITER is well positioned to provide a control actuator capable of having a significant effect on the sawtooth behaviour.
This paper describes the system architecture of a newly constructed radio telescope – the Boolardy engineering test array, which is a prototype of the Australian square kilometre array pathfinder telescope. Phased array feed technology is used to form multiple simultaneous beams per antenna, providing astronomers with unprecedented survey speed. The test array described here is a six-antenna interferometer, fitted with prototype signal processing hardware capable of forming at least nine dual-polarisation beams simultaneously, allowing several square degrees to be imaged in a single pointed observation. The main purpose of the test array is to develop beamforming and wide-field calibration methods for use with the full telescope, but it will also be capable of limited early science demonstrations.
Pyroxasulfone dissipation and mobility in the soil was evaluated and compared to S-metolachlor in 2009 and 2010 at two field sites in northern Colorado, on a Nunn fine clay loam, and Olney fine sandy loam soil. Pyroxasulfone dissipation half-life (DT50) values varied from 47 to 134 d, and those of S-metolachlor ranged from 39 to 63 d. Between years, herbicide DT50 values were similar under the Nunn fine clay loam soil. Under the Olney fine sandy loam soil, dissipation in 2009 was minimal under dry soil conditions. In 2010, under the Olney fine sandy loam soil, S-metolachlor and pyroxasulfone had half-lives of 39 and 47 d, respectively, but dissipation rates appeared to be influenced by movement of herbicides below 30 cm. Herbicide mobility was dependent on site-year conditions, in all site-years pyroxasulfone moved further downward in the soil profile compared to S-metolachlor.
To date, very few studies have examined the bi-directional associations between mood disorders (MDs), anxiety disorders (ADs) and substance use disorders (SUDs), simultaneously. The aims of the current study were to determine the rates and patterns of comorbidity of the common MDs, ADs and SUDs and describe the onset and temporal sequencing of these classes of disorder, by sex.
Data came from the 2007 Australian National Survey of Mental Health and Wellbeing, a nationally representative household survey with 8841 (60% response rate) community residents aged 16–85.
Pre-existing mental disorders increase the risk of subsequent mental disorders in males and females regardless of the class of disorder. Pre-existing SUDs increase the risk of subsequent MDs and ADs differentially for males and females. Pre-existing MDs increase the risk of subsequent ADs differentially for males and females.
Comorbidity remains a significant public health issue and current findings point to the potential need for sex-specific prevention and treatment responses.