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Who is a credible source of preventive advice? An experimental questionnaire study of general public attitudes towards role expansion in health and social care
No full textObjectives: To investigate comparative source credibility for three types of health and social care professionals when giving preventive health and safety advice relating to ‘traditional’ or ‘expanded’ prevention roles. Design: An experimental between subjects questionnaire study presenting nine combinations of professional (General Practitioner(GP); Health Visitor; Firefighter) and prevention topic (stopping smoking; preventing cot death or fire safety). Combinations were either congruent with a traditional role (e.g. Health Visitor and cot death), or an expanded role (e.g. Firefighter and stopping smoking). Methods: Adults were recruited from public locations in a large metropolitan region in Northern England. Participants were randomised to complete a validated 18-item source credibility questionnaire for one combination of professional and topic. Ratings overall and for the three dimension subscales were compared for traditional and expanded role combinations using Mann-Whitney tests. Results: 369 participants completed the questionnaire (49.3% women, 64% White British, age range 16-83). Ratings were generally high across professions and scenarios. Participants rated professionals as significantly more credible overall (U=12199, p=.002, d=0.32) and competent (U=8994, p<.001, d=0.70) where scenarios related to their traditional roles than expanded roles yet equally as caring (U=14905, p=.816, d=0.02) and trustworthy (U=14083, p=.277, d=0.11). Conclusions: This initial evidence may suggest that the competence dimension of source credibility is specific to professional identity; large effects on individual subscales may have a small effect on source credibility overall. Public sector professionals may be perceived as caring and trustworthy deliverers of advice on a wide range of topics not traditionally associated with their job role, but less competent. Public communications about the role expansion agenda may support policy implementation; further research on different combinations in a larger sample is neede
Timescales of crystal mush mobilization in the Bárðarbunga-Veiðivötn volcanic system based on olivine diffusion chronometry
No full textThe timescales of magmatic processes within a volcanic system may be variable over a volcano’s geological history. Crystals reflect environmental perturbations under which they grew, and compositional gradients quenched inside crystals on eruption can be exploited to extract timescales of magmatic processes. Here, we use multi-element diffusion chronometry in olivine macrocrysts to recover their residence time in a melt which ultimately erupted at the surface. The macrocrysts were mobilized by the carrier melt from mushy layers in the magma reservoir, and diffusion timescales likely reflect the time interval between mush disaggregation, ascent and eruption. To unravel the evolution of mush disaggregation timescales with time, we target earlyHolocene, middle-Holocene and historical magmatic units erupted in the Bárðarbunga-Veiðivötn volcanic system in Iceland’s Eastern Volcanic Zone. Macrocryst contents vary between samples; early-Holocene samples are highly phyric (10-45 vol% macrocrysts) and contain gabbroic nodules, whereas middle-Holocene (5-15 vol%) and historical units (5-10 vol%) tend to be generally less phyric. Early-Holocene olivine macrocrysts have core compositions in the range Fo84-87, whilst middle-Holocene and historical samples record a wider range in core compositions from Fo80 to Fo86.5. Olivine rims are in chemical equilibrium with their carrier liquid, and are slightly more evolved in early-Holocene units (Fo76-81) compared to middle-Holocene (Fo78-80) and historical (Fo81-83) units. Diffusion chronometry reveals that the timescale between mush disaggregation and eruption has changed over time, with timescales getting shorter approaching recent times. Early-Holocene olivine macrocrysts dominantly record Fe-Mg diffusion timescales between 200-400 days, whilst middle-Holocene and historical units typically record timescales of about 70 and 60 days, respectively. Barometric studies suggest that melts and crystals are likely stored and gradually transferred throughout an interconnected multi-tiered system that ultimately culminate in a mid-crustal reservoir(s) at about 6.8-7.5 ± 2.5 km depth, where final disaggregation by the carrier liquid took place. We argue that, as a result of extensional processes enhanced by rifting events, well-mixed melts got drawn into mid-crustal reservoir(s) causing crystal mush loosening and mobilization. In addition, we propose that more energy in the form of heat and/or melt supply was required in the early Holocene to break up the dense mush fabric and convert it into an eruptible magma. Conversely, as evidenced by the diverse macrocryst content of the historical units and by the lack of gabbroic nodules, the system has become characterized by a less compact mush fabric since at least the middle-Holocene, such that fresh injection of melt would easily loosen and mobilize the mush, resulting in an eruption within a couple of months. This study provides evidence that along axial rift settings, rifting-related processes can help to “pull the mush apart” with no requirement for primitive magma injection as an eruption trigger. Furthermore, we provide evidence that in the Bárðarbunga-Veiðivötn volcanic system specifically, the time between mush disaggregation and eruption has decreased considerably with time, indicating shorter warning times before imminent eruptions
Predictive Descriptor Observer Design for a Class of LTI Systems with Applications to Quadrotor Trajectory Tracking
No full textThis paper deals with sensor fault tolerant control design and large delay compensation for a class of linear time-invariant (LTI) systems. Based on predictor-based state transformation and predictive descriptor observer design, both of state and output feedback control laws are constructed. Within the framework of Lyapunov-Krasovskii functionals, a set of stability conditions are identified. The closed-loop systems is globally asymptotically stable at the origin under the state feedback and is ultimately bounded under the output feedback. Finally, the proposed design is validated through numerical simulations and then implemented on a quadrotor trajectory tracking test. Both simulation and experimental results demonstrate the effectiveness of the proposed design
Gravity and rotation drag the magnetic field in high-mass star formation
No full textThe formation of hot stars out of the cold interstellar medium lies at the heart of astrophysical research. Understanding the importance of magnetic fields during star formation remains a major challenge. With the advent of the Atacama Large Millimeter Array, the potential to study magnetic fields by polarization observations has tremendously progressed. However, the major question remains how much magnetic fields shape the star formation process or whether gravity is largely dominating. Here, we show that for the high-mass star-forming region G327.3 the magnetic field morphology appears to be dominantly shaped by the gravitational contraction of the central massive gas core where thestar formation proceeds. We find that in the outer parts of the region, the magnetic field is directed toward the gravitational center of the region. Filamentary structures feeding the central core exhibit U-shaped magnetic field morphologies directed toward the gravitational center as well, again showingthe gravitational drag toward the center. The inner part then shows rotational signatures, potentially associated with an embedded disk, and there the magnetic field morphology appears to be rotationally dominated. Hence, our results demonstrate that for this region gravity and rotation are dominatingthe dynamics and shaping the magnetic field morphology
Accuracy of smartphone video for contactless measurement of hand tremor frequency
No full textBackground Computer vision can measure movement from video without the time and access limitations of hospital accelerometry / electromyography, or the requirement to hold or strap a smartphone accelerometer. Objective To compare computer vision measurement of hand tremor frequency from smartphone video with a gold standard measure, accelerometer. Methods 37 smartphone videos of hands at rest and in posture, were recorded from 15 participants with tremor diagnoses (9 Parkinson’s, 5 Essential Tremor, 1 Functional Tremor). Video pixel movement was measured using the computing technique of optical flow, with contemporaneous accelerometer recording. Fast Fourier Transform and Bland-Altman analysis were applied. Tremor amplitude was scored by two clinicians. Results Bland-Altman analysis of dominant tremor frequency from smartphone video compared with accelerometer showed excellent agreement: 95% limits of agreement -0.38 Hz to +0.35Hz. In 36 out of 37 videos (97%) there was <0.5 Hz difference between computer vision and accelerometer measurement. There was no significant correlation between the level of agreement and tremor amplitude. Conclusion The study suggests a potential new, contactless ‘point and press’ measure of tremor frequency within standard clinical settings or telemedicine
Improving Image Similarity Learning by Adding External Memory
No full textThe type of neural networks widely used in artificial intelligence applications mixes its computation and memory modules in neuron weights and activities. The previously learned information are stored in network weights. When dealing with complex data, e.g., those possessing diverse content or containing long-sequences, some information stored in the weights can be altered drastically or wiped as the training goes, but they are not necessarily unimportant. External memory is a recent technique proposed to prevent from forgetting significant previously learned information. In this work, we aim at taking advantage of this recent technique to advance the similarity learning task that is critical in many real-world artificial intelligence applications. We propose suitable external memory design supported by extended attention mechanism. Two different kinds of memory modules are proposed so that the similarity learning process can dynamically shift focus over a wide range of diverse content contained by the training data. Effectiveness of the proposed method is demonstrated through evaluations based on different image retrieval tasks and compared against various state-of-the-art algorithms in the field
Breast cancer risk genes: association analysis in more than 113,000 women
No full textBackground Gene-panel testing for breast cancer susceptibility is widely used, but for many genes, the evidence for association with breast cancer is weak, underlying risk estimates are imprecise, and reliable subtype-specific risks are lacking. Methods We performed gene panel sequencing for 34 putative susceptibility genes on samples from 60,466 female breast cancer cases and 53,461 controls. We estimated odds ratios (ORs) for overall breast cancer and tumor subtypes, separately for protein truncating and rare missense variants, in aggregate. We evaluated missense-variant associations by domain and according to classification of pathogenicity. Results Protein-truncating variants were associated with overall breast-cancer risk at P<0.0001 for five genes: ATM, BRCA1, BRCA2, CHEK2 and PALB2. Associations between risk and truncating variants of four other genes (BARD1, RAD51C, RAD51D and TP53) were significant (P<0.05) and had Bayesian false discovery probabilities <5%. The upper 95% confidence limit excluded a twofold risk for overall breast cancer for truncating variants of 19 of the remaining 25 genes. ORs were higher for estrogen receptor (ER)-positive disease for CHEK2 and ATM, and higher for ER-negative disease for BARD1, BRCA1, BRCA2, PALB2, RAD51C, RAD51D and TP53. Rare missense variants in CHEK2, ATM and TP53, in aggregate, were associated with risk (P<0.001). For BRCA1, BRCA2 and TP53, missense variants classified as pathogenic by standard criteria were associated in aggregate with risk, the risk being similar to that of truncating variants. Conclusions These results define the genes most clinically useful for inclusion on panels for breast cancer risk prediction, and estimates of the risks associated with truncating variants, to guide genetic counselling
Eye Movement Desensitisation and Reprocessing Therapy for psychosis (EMDRp): Protocol of a feasibility randomised controlled trial with Early Intervention service users
No full textAim: Traumatic events are involved in the development and maintenance of psychotic symptoms.There are few trials exploring trauma-focused treatments as interventions for psychotic symptoms,especially in individuals with early psychosis. This trial will evaluate the feasibility and acceptabilityof conducting a definitive trial of Eye Movement Desensitisation and Reprocessing for psychosis(EMDRp) in people with early psychosis.Methods: 60 participants with first episode psychosis and a history of a traumatic/adverse lifeevent(s) will be recruited from early intervention services in the North West of England andrandomised to receive 16 sessions of EMDRp + Treatment as Usual (TAU) or TAU alone. Participantswill be assessed at baseline, 6 months and 12 months post-randomisation using several measures ofpsychotic symptoms, trauma symptoms, anxiety, depression, functioning, service-user definedrecovery, health economics indicators and quality of life. Two nested qualitative studies to assessparticipant feedback of therapy and views of professional stakeholders on the implementation ofEMDRp into services will also be conducted. The feasibility of a future definitive efficacy and costeffectivenessevaluation of EMDRp will be tested against several outcomes, including ability torecruit and randomise participants, trial retention at 6- and 12-month follow-up assessments,treatment engagement and treatment fidelity.Conclusions: If it is feasible to deliver a multi-site trial of this intervention, it will be possible toevaluate whether EMDRp represents a beneficial treatment to augment existing evidence-basedcare of individuals with early psychosis supported by early intervention services
Robust Enhanced Trend Filtering with Unknown Noise
No full textOne important step in time series analysis is the extraction of an underlying trend. However, the true trend is oftensubmerged by complex background noise, espcially non-Gaussian noise or outliers. Accurate trend extraction againstoutliers from a raw signal is a challenging task. To address this challenge, this paper extends l1 trend filtering to arobust enhanced trend filtering called RobustETF by combining mix of Gaussian (MoG) and non-convex sparsity-inducingfunctions. We first model the noise as a MoG distribution to allow RobustETF to be robust in the presence of anytype of non-Gaussian noise or outliers. After that, to handle the biased estimation of the l1 norm, we use the Gibbsdistribution embedding smoothed and non-convex sparsity-inducing functions to faithfully preserve the amplitude of thetrend. Furthermore, we design an extended EM algorithm to solve the resulting non-convex optimization problem. Finally,we show the results of experiments on both real-world and synthetic data to compare the performance of the proposedalgorithm against other state-of-the-art methods. Finally, the corresponding Matlab codes are available at https://github.com/ZhaoZhibin/RobustETF