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The medical licensing assessment will fall short of determining whether a UK medical graduate behaves ethically
Get PDFUK medical graduates will soon need to pass the medical licensing assessment, which assesses skills and knowledge in ethics using multiple choice questions (eg single best answer questions) and objective structured clinical examination. However, educational leaders have recognised that these methods lack the sophistication needed to accurately assess medical ethics. The reasons are two-fold. First, there may be a knowledge and practice gap in medical schools when it comes to preparing students for the assessment. To this end, this article shares peer advice about how best to use objective structured clinical examinations and single best answer questions for assessing medical ethics to help prepare students for the medical licensing assessment. Second, the design of the assessment is unlikely to adequately measure graduates' ethical values and behaviour in real world scenarios. Further work is needed to design assessments that are sophisticated enough to examine candidates' ethical reasoning and their actual behaviour
Fatigue and vigilance in medical experts detecting breast cancer
Get PDFAn abundance of laboratory-based experiments has described a vigilance decrement of reducing accuracy to detect targets with time on task, but there are few real-world studies, none of which have previously controlled the environment to control for bias. We describe accuracy in clinical practice for 360 experts who examined >1 million women’s mammograms for signs of cancer, whilst controlling for potential biases. The vigilance decrement pattern was not observed. Instead, test accuracy improved over time, through a reduction in false alarms and an increase in speed, with no significant change in sensitivity. The multiple-decision model explains why experts miss targets in low prevalence settings through a change in decision threshold and search quit threshold and propose it should be adapted to explain these observed patterns of accuracy with time on task. What is typically thought of as standard and robust research findings in controlled laboratory settings may not directly apply to real-world environments and instead large, controlled studies in relevant environments are needed
Benzotrifuran-based donor–acceptor covalent organic frameworks for enhanced photocatalytic hydrogen generation
No full textA novel benzotrifuranyl COF with excellent photovoltaic properties and low exciton binding energy was successfully constructed and used for efficient photolysis of water
Clinical and public health implications of increasing notifications of LEE-negative Shiga toxin-producing Escherichia coli in England, 2014–2022
Get PDFIntroduction. Shiga toxin-producing Escherichia coli (STEC) belong to a diverse group of gastrointestinal pathogens. The pathogenic potential of STEC is enhanced by the presence of the pathogenicity island called the Locus of Enterocyte Effacement (LEE), including the intimin encoding gene eae.
Gap statement. STEC serotypes O128:H2 (Clonal Complex [CC]25), O91:H14 (CC33), and O146:H21 (CC442) are consistently in the top five STEC serotypes isolated from patients reporting gastrointestinal symptoms in England. However, they are eae/LEE-negative and perceived to be a low risk to public health, and we know little about their microbiology and epidemiology.
Aim. We analysed clinical outcomes and genome sequencing data linked to patients infected with LEE-negative STEC belonging to CC25 (O128:H2, O21:H2), CC33 (O91:H14) and, and CC442 (O146:H21, O174:H21) in England to assess the risk to public health.
Results. There was an almost ten-fold increase between 2014 and 2022 in the detection of all STEC belonging to CC25, CC33 and CC442 (2014 n=38, 2022 n=336), and a total of 1417 cases. There was a higher proportion of female cases (55–70 %) and more adults than children, with patients aged between 20–40 and >70 most at risk across the different serotypes. Symptoms were consistent across the three dominant serotypes O91:H14 (CC33), O146:H21 (CC442) and O128:H2 (CC25) (diarrhoea >75 %; bloody diarrhoea 25–32 %; abdominal pain 64–72 %; nausea 37–45 %; vomiting 10–24 %; and fever 27–30 %). Phylogenetic analyses revealed multiple events of acquisition and loss of different stx-encoding prophage. Additional putative virulence genes were identified including iha, agn43 and subA.
Conclusions. Continued monitoring and surveillance of LEE-negative STEC infections is essential due to the increasing burden of infectious intestinal disease, and the risk that highly pathogenic strains may emerge following acquisition of the Shiga toxin subtypes associated with the most severe clinical outcomes
Characterization of ferroelectric domains in magnetite (Fe3O4)
No full textMagnetite has long been investigated across many disciplines due to the interplay between its ferroic order parameters, namely, its ferrimagnetism, ferroelasticity, and ferroelectricity. Despite this, the experimental difficulty in measuring low temperature real space images of the ferroelectric domains has meant that the local behavior of ferroelectric domains emergent below the ∼38 K phase transition have yet to be realized. This work presents real space images of the ferroelectric domains and uses piezoresponse force microscopy as a function of temperature to probe the onset of piezoelectricity and ferroelectricity across the 38 K transition
Ultrastructure of macromolecular assemblies contributing to bacterial spore resistance revealed by in situ cryo-electron tomography
Get PDFBacterial spores owe their incredible resistance capacities to molecular structures that protect the cell content from external aggressions. Among the determinants of resistance are the quaternary structure of the chromosome and an extracellular shell made of proteinaceous layers (the coat), the assembly of which remains poorly understood. Here, in situ cryo-electron tomography on lamellae generated by cryo-focused ion beam micromachining provides insights into the ultrastructural organization of Bacillus subtilis sporangia. The reconstructed tomograms reveal that early during sporulation, the chromosome in the forespore adopts a toroidal structure harboring 5.5-nm thick fibers. At the same stage, coat proteins at the surface of the forespore form a stack of amorphous or structured layers with distinct electron density, dimensions and organization. By analyzing mutant strains using cryo-electron tomography and transmission electron microscopy on resin sections, we distinguish seven nascent coat regions with different molecular properties, and propose a model for the contribution of coat morphogenetic proteins
Real-time, noise and drift resilient formaldehyde sensing at room temperature with aerogel filaments
No full textFormaldehyde, a known human carcinogen, is a common indoor air pollutant. However, its real-time and selective recognition from interfering gases remains challenging, especially for low-power sensors suffering from noise and baseline drift. We report a fully 3D-printed quantum dot/graphene-based aerogel sensor for highly sensitive and real-time recognition of formaldehyde at room temperature. By optimizing the morphology and doping of printed structures, we achieve a record-high and stable response of 15.23% for 1 part per million formaldehyde and an ultralow detection limit of 8.02 parts per billion consuming only ∼130-microwatt power. On the basis of measured dynamic response snapshots, we also develop intelligent computational algorithms for robust and accurate detection in real time despite simulated substantial noise and baseline drift, hitherto unachievable for room temperature sensors. Our framework in combining materials engineering, structural design, and computational algorithm to capture dynamic response offers unprecedented real-time identification capabilities of formaldehyde and other volatile organic compounds at room temperature
A neo-positivist theory of scientific change
Get PDFHistorians of science appear to agree on two things. There is a shortage of large-scale histories of science, and positivism is best avoided. In fact, we have many big-picture histories of science. The problem is not the lack of such histories but the lack of agreement between them. They differ with respect to chronology, geography, narrative structure, favoured disciplines, recent revisionism and epistemology. To make the most of these differences, I resurrect an idea from nineteenth-century positivism, namely that science evolves by the migration of methods from one matter to another. This is an old form of materialism that complements more recent materialisms. The neo-positivist approach may be illustrated by matters as varied as stars, crystals and the Pacific Ocean. If we revive positivism as an intellectual project, we might also revive the social goal of positivism, which was to use the history of science to make the world more rational. A present-day version of this project is to use the history of science to defend the humanities as a rational enterprise
Postintervention immunological and entomological survey of lymphatic filariasis in the City of Olinda, Brazil, 2015–2016
No full textLymphatic filariasis (LF) is a leading cause of disability due to infectious disease worldwide. The Recife Metropolitan Region (RMR) is the only remaining focus of LF in Brazil, where the parasite Wuchereria bancrofti is transmitted solely by the mosquito Culex quinquefasciatus. This study reports the results of transmission assessment surveys and molecular xenomonitoring in the city of Olinda, RMR, after nearly 15 years (2015–2016) of interventions for LF elimination. Participants were screened for W. bancrofti antigen via immunochromatographic card tests (ICT) in: 1) door-to-door surveys conducted for all children aged 5–7 years from 4 out of 17 intervention areas treated with at least five annual doses of mass drug administration (MDA), and 2) a two-stage cluster sampling survey of residents aged 5 years and older in non-MDA areas. Mosquitoes were collected via handheld aspirators in four MDA areas, differentiated by species, sex, and physiological status, pooled into groups of up to 10 blood-fed, semigravid, and gravid mosquitoes, and screened for W. bancrofti infection by real-time quantitative polymerase chain reaction (RT-qPCR). All 1,170 children from MDA areas and the entire population sample of 990 residents in non-MDA areas were ICT negative. In MDA areas, a total of 3,152 female Cx. quinquefasciatus mosquitoes in 277 households (range, 0–296 mosquitoes per house) were collected via aspiration. RT-qPCR of 233 pools of mosquitos were negative for W. bancrofti RNA; an independent reference laboratory confirmed these results. These results provide evidence that LF transmission has been halted in this setting
Reinforcement learning-based multiobjective control of grid-connected wind farms
No full textThis article aims to design a multiobjective controller with a primary focus on mitigating the wake interference in wind farms to increase their long-term power generation compared with the method without coordination in tackling the wake effect. What is more, this farm-level controller endeavors to keep turbines online in the event of a voltage fault and offer ancillary services to the grid while minimizing the farm power losses. Model-free reinforcement learning (RL) is promising in coping with such challenges since it can train a multiobjective control policy by interacting with the environment. In this article, we first construct a grid-connected wind farm simulator as the environment to collect training samples for model-free RL. Then, we erect three wind farm control objectives: maximizing the power generation of the wind farm by overcoming the wake effect, facilitating the fault-ride-through capability of wind turbines, and enhancing the frequency stability of the grid. Finally, an appropriate reward function is designed to induce RL agents to achieve these objectives. Results show that the proposed method can obviously increase the power generation compared with the method ignoring the wake effect. Furthermore, the method showcases it is capable of controlling turbines to ride through voltage faults of the grid and assisting the grid to return to its nominal frequency