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We have observed the G23 field of the Galaxy AndMass Assembly (GAMA) survey using the Australian Square Kilometre Array Pathfinder (ASKAP) in its commissioning phase to validate the performance of the telescope and to characterise the detected galaxy populations. This observation covers ~48 deg2 with synthesised beam of 32.7 arcsec by 17.8 arcsec at 936MHz, and ~39 deg2 with synthesised beam of 15.8 arcsec by 12.0 arcsec at 1320MHz. At both frequencies, the root-mean-square (r.m.s.) noise is ~0.1 mJy/beam. We combine these radio observations with the GAMA galaxy data, which includes spectroscopy of galaxies that are i-band selected with a magnitude limit of 19.2. Wide-field Infrared Survey Explorer (WISE) infrared (IR) photometry is used to determine which galaxies host an active galactic nucleus (AGN). In properties including source counts, mass distributions, and IR versus radio luminosity relation, the ASKAP-detected radio sources behave as expected. Radio galaxies have higher stellar mass and luminosity in IR, optical, and UV than other galaxies. We apply optical and IR AGN diagnostics and find that they disagree for ~30% of the galaxies in our sample. We suggest possible causes for the disagreement. Some cases can be explained by optical extinction of the AGN, but for more than half of the cases we do not find a clear explanation. Radio sources aremore likely (~6%) to have an AGN than radio quiet galaxies (~1%), but the majority of AGN are not detected in radio at this sensitivity.
Perceived discrimination (PD) is reliably and strongly associated with partisan identity (PID) among US immigrant minorities such as Latinos and Asian Americans. Yet whether PD causes PID remains unclear, since it is possible that partisanship influences perceptions of discrimination or that other factors drive the observed association. Here, we assess the causal influence of group-level PD on PID using five experiments with Latino and Asian American adults. These experiments varied in important ways: they took place inside and outside the lab, occurred prior to and during Donald Trump’s presidential campaign, and tested different manifestations of PD and partisan attitudes (total n = 2,528). These efforts point to a simple but unexpected conclusion: our experiments and operationalizations do not support the claim that group-targeted PD directly causes PID. These results have important implications for understanding partisanship among immigrants and their co-ethnics and the political incorporation of Latinos and Asian Americans.
Around 30% of individuals with schizophrenia remain symptomatic and significantly impaired despite antipsychotic treatment and are considered to be treatment resistant. Clinicians are currently unable to predict which patients are at higher risk of treatment resistance.
To determine whether genetic liability for schizophrenia and/or clinical characteristics measurable at illness onset can prospectively indicate a higher risk of treatment-resistant psychosis (TRP).
In 1070 individuals with schizophrenia or related psychotic disorders, schizophrenia polygenic risk scores (PRS) and large copy number variations (CNVs) were assessed for enrichment in TRP. Regression and machine-learning approaches were used to investigate the association of phenotypes related to demographics, family history, premorbid factors and illness onset with TRP.
Younger age at onset (odds ratio 0.94, P = 7.79 × 10−13) and poor premorbid social adjustment (odds ratio 1.64, P = 2.41 × 10−4) increased risk of TRP in univariate regression analyses. These factors remained associated in multivariate regression analyses, which also found lower premorbid IQ (odds ratio 0.98, P = 7.76 × 10−3), younger father's age at birth (odds ratio 0.97, P = 0.015) and cannabis use (odds ratio 1.60, P = 0.025) increased the risk of TRP. Machine-learning approaches found age at onset to be the most important predictor and also identified premorbid IQ and poor social adjustment as predictors of TRP, mirroring findings from regression analyses. Genetic liability for schizophrenia was not associated with TRP.
People with an earlier age at onset of psychosis and poor premorbid functioning are more likely to be treatment resistant. The genetic architecture of susceptibility to schizophrenia may be distinct from that of treatment outcomes.
Recent years have seen a renaissance of conjoint survey designs within social science. To date, however, researchers have lacked guidance on how many attributes they can include within conjoint profiles before survey satisficing leads to unacceptable declines in response quality. This paper addresses that question using pre-registered, two-stage experiments examining choices among hypothetical candidates for US Senate or hotel rooms. In each experiment, we use the first stage to identify attributes which are perceived to be uncorrelated with the attribute of interest, so that their effects are not masked by those of the core attributes. In the second stage, we randomly assign respondents to conjoint designs with varying numbers of those filler attributes. We report the results of these experiments implemented via Amazon's Mechanical Turk and Survey Sampling International. They demonstrate that our core quantities of interest are generally stable, with relatively modest increases in survey satisficing when respondents face large numbers of attributes.
is a smooth complex algebraic variety. A necessary condition for a complex topological vector bundle on
(viewed as a complex manifold) to be algebraic is that all Chern classes must be algebraic cohomology classes, that is, lie in the image of the cycle class map. We analyze the question of whether algebraicity of Chern classes is sufficient to guarantee algebraizability of complex topological vector bundles. For affine varieties of dimension
, it is known that algebraicity of Chern classes of a vector bundle guarantees algebraizability of the vector bundle. In contrast, we show in dimension
that algebraicity of Chern classes is insufficient to guarantee algebraizability of vector bundles. To do this, we construct a new obstruction to algebraizability using Steenrod operations on Chow groups. By means of an explicit example, we observe that our obstruction is nontrivial in general.
We measure the cosmic star formation history out to z = 1.3 using a sample of 918 radio-selected star-forming galaxies within the 2-deg2 COSMOS field. To increase our sample size, we combine 1.4-GHz flux densities from the VLA-COSMOS catalogue with flux densities measured from the VLA-COSMOS radio continuum image at the positions of I < 26.5 galaxies, enabling us to detect 1.4-GHz sources as faint as 40 μJy. We find that radio measurements of the cosmic star formation history are highly dependent on sample completeness and models used to extrapolate the faint end of the radio luminosity function. For our preferred model of the luminosity function, we find the star formation rate density increases from 0.017 M⊙ yr−1 Mpc−3 at z ∼ 0.225 to 0.092 M⊙ yr−1 Mpc−3 at z ∼ 1.1, which agrees to within 40% of recent UV, IR and 3-GHz measurements of the cosmic star formation history.
This study aimed to estimate the cost-effectiveness of Coblation compared with cold steel tonsillectomy in adult and paediatric patients in the UK.
Decision analysis was undertaken by combining published clinical outcomes with resource utilisation estimates derived from a panel of clinicians.
Using a cold steel procedure instead of Coblation is expected to generate an incremental cost of more than £2000 for each additional avoided haemorrhage, and the probability of cold steel being cost-effective was approximately 0.50. Therefore, the cost-effectiveness of the two techniques was comparable. When the published clinical outcomes were replaced with clinicians’ estimates of current practice, Coblation was found to improve outcome for less cost, and the probability of Coblation being cost-effective was at least 0.70.
A best-case scenario suggests Coblation affords the National Health Service a cost-effective intervention for tonsillectomy in adult and paediatric patients compared with cold steel procedures. A worst-case scenario suggests Coblation affords the National Health Service an equivalent cost-effective intervention for adult and paediatric patients.
The two major approaches to studying macroevolution in deep time are the fossil record and reconstructed relationships among extant taxa from molecular data. Results based on one approach sometimes conflict with those based on the other, with inconsistencies often attributed to inherent flaws of one (or the other) data source. Any contradiction between the molecular and fossil records represents a failure of our ability to understand the imperfections of our data, as both are limited reflections of the same evolutionary history. We therefore need to develop conceptual and mathematical models that jointly explain our observations in both records. Fortunately, the different limitations of each record provide an opportunity to test or calibrate the other, and new methodological developments leverage both records simultaneously. However, we must reckon with the distinct relationships between sampling and time in the fossil record and molecular phylogenies. These differences impact our recognition of baselines and the analytical incorporation of age estimate uncertainty.
OBJECTIVES/SPECIFIC AIMS: Autism spectrum disorder (ASD) is a neurodevelopmental disorder that affects one in 68 children. Children with ASD have 2 core areas of difficulty: social communication skills and restricted and repetitive interests and patterns of behavior. Children with social skills deficits are at higher risk of developing mental health problems, and underdeveloped social skills predict poorer quality of life in adulthood. Therapies have been developed to help people with ASD improve social abilities in childhood, often involving a clinician directly teaching social skills lessons, either one-on-one or in a group setting. However, children with ASD can become anxious when interacting with other people and have an intrinsic motivation to interact with technology. To capitalize on this interest, this research team developed a robot, the socially animated machine (SAM) to teach social skills to children with ASD. Previous research found that this intervention was feasible and enjoyable for children with ASD and average cognitive ability, and participants improved in complex emotion recognition following intervention. The purpose of this study was to determine whether participants of all IQ levels were motivated by the SAM intervention, and whether they improved on emotion identification, facial recognition, social skills, and adaptive behavior. METHODS/STUDY POPULATION: This study recruited 20 children with ASD ages 5–14. Children completed tasks measuring ASD symptoms, IQ, receptive language, facial recognition, and emotion identification and were assigned to the control group (nonemotion dance games with SAM robot) or the intervention group (emotion games with SAM robot). Parents and teachers completed questionnaires about the child’s social skills. Following the robot intervention, facial recognition, emotion identification, and social skills were measured again, and parents and children rated participant enjoyment during the robot interaction. RESULTS/ANTICIPATED RESULTS: Overall, parents and children in both groups rated the robot interaction as highly enjoyable and motivating (parent ratings: M=26.4 out of 30, child ratings: M=17.5 out of 20). There were no differences between groups on post-test measures when controlling for pre-test scores (all p>0.05). Both groups improved over time on emotion identification accuracy (intervention: M=13.0% improvement, t=2.57, p<0.05; control: M=10.2% improvement, t=2.38, p<0.05) and parent-rated social skills (intervention: pre-test M=113.8, post-test M=100.6, t=−3.37, p=0.01; Control: pre-test M=107.9, post-test M=89.0, t=−2.83, p<0.05; decrease in scores indicates improvement). Teachers saw a decrease in problem behaviors for the intervention group (pre-test M=127.4, post-test M=119.6, t=−3.79, p<0.01, decrease in scores indicates improvement). DISCUSSION/SIGNIFICANCE OF IMPACT: This study shows that children with ASD and all levels of cognitive ability enjoyed and were motivated by the SAM robot intervention. This is particularly important for children with ASD who often have difficulty with attention and motivation. Children who are intrinsically motivated by the learning process will be more likely to benefit from it; therefore, continuing to pursue the methodology of robot-based interventions with this population is a worthwhile endeavor.
Complete body fossils of salamanders are relatively rare, but provide critical information on the evolutionary roots of extant urodele clades. We describe new specimens of the fossil salamandrids Taricha oligocenica Van Frank, 1955, and Taricha lindoei Naylor, 1979, from the Oligocene Mehama and John Day formations of Oregon that illustrate aspects of skeletal morphology previously unseen in these taxa, and contribute to our understanding of population-level variation. Morphological analysis of these specimens supports the classification of T. oligocenica and T. lindoei as two different species, distinct from extant Taricha. Parsimony-based, heuristic analysis of phylogeny using 108 morphological characters for 40 taxa yields different results from a phylogenetic analysis that excludes four taxa known only via vertebrae. Our smaller analysis generally agrees with molecular phylogenies of the family Salamandridae, but with poorer resolution for molgin newts, especially between Taricha and Notophthalmus. The analysis including all taxa produced polytomies mostly related to complications from several fossil taxa. The presence or absence of dorsally expanded, sculptured neural spine tables on trunk vertebrae, an important character in past descriptions of fossil salamandrids, appears to be either homoplastic within the Salamandridae, or requires an expansion of characters or character states. Taricha oligocenica and T. lindoei are separate species of an at least 33 million-year-old clade, but their relationships with each other and extant North American salamandrids remain unclear with current levels of morphological data. Salamandrid research requires additional morphological data, particularly for the vertebrae and ribs, to better resolve salamandrid evolutionary history through morphological characters.
In sub-Saharan Africa (SSA), the association of crops and livestock in mixed farming systems generally benefits both enterprises. This paper focuses on the main contributions of livestock to crop production: the use of manure and animal draught power to produce crops and the investment of income from livestock into technologies that benefit crop production. In low-input, grazing-based feeding operations, manure is a vital soil fertility amendment. In these systems, penning livestock overnight on fields, fallow between cropping periods, returns both manure and urine to the soil and results in much higher crop yields than if manure only is gathered from stalls and spread onto fields. However, most farmers have insufficient manure to sustain food production. Nutrient harvests often exceed nutrient inputs, requiring a much greater use of fertilizers to arrest soil nutrient depletion. The opposite may be true for mixed farming where livestock are given food in confinement. In these emerging systems, the continuous importation of food (and fertilizer) can result in nutrient surpluses with subsequent soil nutrient build-up and loss. The contribution of animal power to crop production is relatively new in Africa. Animal power affects the amount of land cultivated by farmers, crop selection, the yield per farm and per ha, and on the participation and work load of people (family members and outside labour) involved in crop production and its associated activities. In addition to the impacts of manure and draught power on crop production, income derived from livestock is often invested in inputs that enhance crop production. At the ‘micro’ level, livestock income influences crop production (1) directly by allowing households to invest in productive inputs such as fertilizer, hired labour, and carts and (2) indirectly by allowing poor households to improve their nutritional status and, therefore, the productivity of their most important resource, their own labour. At the ‘macro’ level, increased livestock exports have a large stimulating effect on the demand for locally produced goods and services, particularly basic food crops. Thus, increasing the productivity of the livestock sector, including an emphasis on the policy and institutional environment influencing marketing and trade, is an important element of a development strategy focused on stimulating economic growth and alleviating poverty.
In recent years, political and social scientists have made increasing use of conjoint survey designs to study decision-making. Here, we study a consequential question which researchers confront when implementing conjoint designs: How many choice tasks can respondents perform before survey satisficing degrades response quality? To answer the question, we run a set of experiments where respondents are asked to complete as many as 30 conjoint tasks. Experiments conducted through Amazon’s Mechanical Turk and Survey Sampling International demonstrate the surprising robustness of conjoint designs, as there are detectable but quite limited increases in survey satisficing as the number of tasks increases. Our evidence suggests that in similar study contexts researchers can assign dozens of tasks without substantial declines in response quality.
There is variation regarding the use of surgery and interventional radiological techniques in the management of epistaxis. This review evaluates the effectiveness of surgical artery ligation compared to direct treatments (nasal packing, cautery), and that of embolisation compared to direct treatments and surgery.
A systematic review of the literature was performed using a standardised published methodology and custom database search strategy.
Thirty-seven studies were identified relating to surgery, and 34 articles relating to interventional radiology. For patients with refractory epistaxis, endoscopic sphenopalatine artery ligation had the most favourable adverse effect profile and success rate compared to other forms of surgical artery ligation. Endoscopic sphenopalatine artery ligation and embolisation had similar success rates (73–100 per cent and 75–92 per cent, respectively), although embolisation was associated with more serious adverse effects (risk of stroke, 1.1–1.5 per cent). No articles directly compared the two techniques.
Trials comparing endoscopic sphenopalatine artery ligation to embolisation are required to better evaluate the clinical and economic effects of intervention in epistaxis.