Absence of Spontaneous Magnetic Fields due to Time-Reversal Symmetry Breaking in Bulk Superconducting UTe_{2}.

We have investigated the low-temperature local magnetic properties in the bulk of molten salt-flux (MSF)-grown single crystals of the candidate odd-parity superconductor UTe_{2} by zero-field muon spin relaxation (µSR). In contrast to previous µSR studies of UTe_{2} single crystals grown by a chemical vapor transport method, we find no evidence of magnetic clusters or electronic moments fluctuating slow enough to cause a discernible relaxation of the zero-field µSR asymmetry spectrum. Consequently, our measurements on MSF-grown single crystals rule out the generation of spontaneous magnetic fields in the bulk that would occur near impurities or lattice defects if the superconducting state of UTe_{2} breaks time-reversal symmetry. This result suggests that UTe_{2} is characterized by a single-component superconducting order parameter.

A scoping review of clinical practices and adherence to UK national guidance related to the placement and position confirmation of adult nasogastric feeding tubes.

INTRODUCTION: The administration of nutrition or medication into the lungs or pleura via a misplaced nasogastric feeding tube is considered a never event. Despite guidance from the National Patient Safety Agency and NHS Improvement this never event is regularly reported. Confirmation of correct placement and correct use of nasogastric tubes requires appropriate actions and decisions by a multidisciplinary team. METHODS: A scoping review identified 43 records that discussed and supported nasogastric tube misplacement as a Never Event. Searches were completed using Web of Science, CINAHL, Google Scholar, British Nursing Index (BNI), as well as selected journals. A further manual search revealed 22 publicly available NHS Trust policies related to nasogastric feeding tube procedures. Items generated between 2011 and 2020 were considered eligible. A thematic analysis was completed to assess adherence to guidance and the practices in place across the NHS. RESULTS: Three key themes were identified as part of the review: referral and authorisation of radiography, examination description, and visualisation of the nasogastric tube tip. Large variations in practice were identified. While there is recognition of national guidance, records showed inconsistency and lacked the required detail to ensure patient safety. CONCLUSION: Despite classification as a never event, it is apparent that there is still room for improvement and further guidance in ensuring patient safety with respect to nasogastric tube insertion. IMPLICATIONS FOR PRACTICE: Practice requires further standardisation whilst also ensuring optimisation and safety. Guidance should address in depth imaging authorisation, language and exact standards of acceptability for imaging the full length of the nasogastric tube.

The efficacy of preliminary clinical evaluation for emergency department chest radiographs with trauma presentations in pre- and post-training situations.

INTRODUCTION: The chest X-ray (CXR) is the most frequently performed radiographic examination. This study evaluates radiographers' ability to localise traumatic CXR pathology and provide a preliminary clinical evaluation (PCE) for these cases. METHODS: This observer study was performed in a district general hospital in the United Kingdom (UK). A 58-case image bank was used with 20 positive cases. Participants were awarded a maximum of three points, based on abnormality recognition and descriptive accuracy. Localisation data were recorded with ROCView. Training was delivered via short online recorded tutorials covering an introduction of a systematic search strategy for CXR, how to recognise the common abnormalities covered in the tests, how to structure a PCE and multiple practice cases to review at participants' own pace. Pre- and post-training data was recorded. RESULTS: Nine participants completed the study. Overall, pooled sensitivity remained consistent (78.9%-78.8%) following training, specificity and accuracy showed improvement of 79.0%-89.9% and 78.9%-86.0% respectively. An increase in the number of correct localisations and PCE scores were also evident. Participants performed better at correctly identifying a pneumothorax compared to skeletal abnormalities. CONCLUSION: Improvements in performance were evident for most participants' abnormality localisations and PCE scores, following the training intervention. The study highlighted areas of CXR PCE that may require further training, such as detecting superimposed or subtle abnormalities. IMPLICATIONS FOR PRACTICE: This study provides additional support for the development of PCE systems in additional areas of imaging practice.

Trapping Alkaline Earth Rydberg Atoms Optical Tweezer Arrays.

Neutral atom qubits with Rydberg-mediated interactions are a leading platform for developing large-scale coherent quantum systems. In the majority of experiments to date, the Rydberg states are not trapped by the same potential that confines ground state atoms, resulting in atom loss and constraints on the achievable interaction time. In this Letter, we demonstrate that the Rydberg states of an alkaline earth atom, ytterbium, can be stably trapped by the same red-detuned optical tweezer that also confines the ground state, by leveraging the polarizability of the Yb^{+} ion core. Using the previously unobserved ^{3}S_{1} series, we demonstrate trapped Rydberg atom lifetimes exceeding 100 µs, and observe no evidence of auto- or photoionization from the trap light for these states. We measure a coherence time of T_{2}=59 µs between two Rydberg levels, exceeding the 28 µs lifetime of untrapped Rydberg atoms under the same conditions. These results are promising for extending the interaction time of Rydberg atom arrays for quantum simulation and computing, and are vital to capitalize on the extended Rydberg lifetimes in circular states or cryogenic environments.

Predicting the role of touchless technologies within diagnostic radiography: Results of an international survey.

INTRODUCTION: The evolution of technology within healthcare is continuing at a rapid rate. Touchless technologies (i.e. those involving gestures and voice commands) are rapidly being integrated into daily life. The aim of this study was to investigate the potential role for such technologies within diagnostic radiography. METHODS: An online survey was developed, piloted and deployed using SurveyMonkey as part of an online radiology congress. Eligible respondents were radiographers or radiologic technologists, including students. The survey covered ten themes relating to the potential role of touchless technologies within diagnostic radiography. Results were analysed using descriptive and inferential statistics. RESULTS: 155 people completed the questionnaire. 100 (64.9%) were women and clinical experience ranged from 13.5 (0-40) years. The majority, 54 (35.1%), had a Bachelor's degree with respondents being from 23 different countries (five continents). 34 (21.9%) respondents did not personally own nor intended to purchase touchless technologies. 89 (84.8%) respondents saw themselves using touchless technologies, if available on current imaging equipment. 25 (16.0%) respondents reported that they currently have access to touchless technologies within their workplace. 88 (81.5%) and 67 (65.0%) respondents reported that they saw voice and gesture controls as being key in improving exam efficiency. CONCLUSION: Participants clearly perceived a role for touchless technologies within diagnostic radiography. Access to such technologies is not yet widely available within X-ray rooms. Voice activated technologies appear more appealing that gesture-based aids. The primary role for such technologies was defined by participants as focusing on improving examination efficiency. IMPLICATIONS FOR PRACTICE: Touchless technologies have been identified and as important and potentially useful in diagnostic radiography. Collaboration between healthcare institutions, industry and academia is required to design and successfully implement these technologies into practice.

Lived experiences of first-year radiation therapy students communicating with patients and radiation therapists - A qualitative review using interpretative phenomenological analysis.

INTRODUCTION: Radiation therapists must possess adaptable communication skills to manage patient-centred care and provide required technical information. Adaptive communication is also an expectation of undergraduate students to gain registration in Australia. The University Of Newcastle's Clinical Reasoning Module (CRM) prepares first-year radiation therapy students for clinical interactions. This research aims to reveal the lived experience of students after completing their first clinical placement. METHODS: An interpretative phenomenological analysis (IPA) approach was the chosen methodology. Audio-recorded semi-structured interviews were conducted with first-year students who had completed the CRM and attended their first placement. Two independent reviewers analysed each data set separately before discussing and agreeing on, and arranging themes into clusters to reveal substantive and sub-themes. RESULTS: Four students were interviewed. Five substantive themes were revealed; 'making sense of the CRM', 'the inner self',' the art of communication', 'the student as a learner' and 'clinical work'. Students' varied clinical experiences were evident, and the interviews allowed a de-brief mechanism. Students related the CRM to the clinical environment and revealed unexpected reactions and emotional responses during their placement. Examples include disclosing the reluctance of patients to interact and talking about dying, which became their new normal. CONCLUSION: This review allowed an opportunity to inquire into the lived experiences of radiation therapy students navigating their way through the clinical environment. Differences between student's emotional intelligence and level of communication reflected their ability to make sense of their experiences in the clinical setting. IMPLICATIONS FOR PRACTICE: While students appeared satisfied with the CRM in preparing them for clinical placement, providing regular de-brief sessions and reviewing clinical practice guidelines to better prepare for psycho-social issues encountered is recommended for overall student well-being.

Colossal anomalous Nernst effect in a correlated noncentrosymmetric kagome ferromagnet.

The transverse voltage generated by a temperature gradient in a perpendicularly applied magnetic field, termed the Nernst effect, has promise for thermoelectric applications and for probing electronic structure. In magnetic materials, an anomalous Nernst effect (ANE) is possible in a zero magnetic field. We report a colossal ANE in the ferromagnetic metal UCo0.8Ru0.2Al, reaching 23 microvolts per kelvin. Uranium's 5f electrons provide strong electronic correlations that lead to narrow bands, a known route to producing a large thermoelectric response. In addition, uranium's strong spin-orbit coupling produces an intrinsic transverse response in this material due to the Berry curvature associated with the relativistic electronic structure. Theoretical calculations show that in UCo0.8Ru0.2Al at least 148 Weyl nodes, and two nodal lines, exist within 60 millielectron volt of the Fermi level. This work demonstrates that magnetic actinide materials can host strong Nernst and Hall responses due to their combined correlated and topological nature.

Survey of monitor specification and viewing conditions in breast screening units in the North West of England.

INTRODUCTION: Monitor specification and viewing conditions are important factors affecting image assessment in mammography. This survey evaluates the different viewing conditions and monitor specifications that exist in acquisition and reporting rooms in UK breast screening units. METHODS: Static (n = 10) and mobile (n = 2) breast screening units were evaluated in North West England. Room illumination levels were measured in 3 locations for each room using a calibrated Lux meter and the specification of 122 monitors recorded. Room layout, wall colour, location and number of doors, windows and light sources were recorded. RESULTS: In reporting rooms, 90/91 of monitors had similar technical specifications and were compliant to guidelines. The ambient light levels ranged from 10 to 25.8 lux. The mean illuminance was 12.32 ± 4.6 lux. In acquisition rooms, great variances appeared in monitor specification and ambient light levels. The majority of monitors (24/34) had 3 megapixel (MB) optimum resolution but the ambient light level ranged from 10 to 1020 lux. The mean illuminance was 105.3 ± 178.8 lux. The mobile units were consistent with each other and compliant with guidelines. CONCLUSION: A lack of consistency and great variances appeared in terms of ambient light levels and monitor specifications in the image acquisition rooms. However, there was excellent consistency among the illumination measurements and the monitors' technical specifications in the reporting rooms. IMPLICATIONS FOR PRACTICE: This research demonstrates, for the first time, the need for further research and specialised guidelines for acquisition rooms.

Evidence for a pressure-induced antiferromagnetic quantum critical point in intermediate-valence UTe2.

UTe2 is a recently discovered unconventional superconductor that has attracted much interest because of its potentially spin-triplet topological superconductivity. Our ac calorimetry, electrical resistivity, and x-ray absorption study of UTe2 under applied pressure reveals key insights on the superconducting and magnetic states surrounding pressure-induced quantum criticality at P c1 = 1.3 GPa. First, our specific heat data at low pressures, combined with a phenomenological model, show that pressure alters the balance between two closely competing superconducting orders. Second, near 1.5 GPa, we detect two bulk transitions that trigger changes in the resistivity, which are consistent with antiferromagnetic order, rather than ferromagnetism. Third, the emergence of magnetism is accompanied by an increase in valence toward a U4+ (5f 2) state, which indicates that UTe2 exhibits intermediate valence at ambient pressure. Our results suggest that antiferromagnetic fluctuations may play a more substantial role on the superconducting state of UTe2 than previously thought.

Interplay of the Spin Density Wave and a Possible Fulde-Ferrell-Larkin-Ovchinnikov State in CeCoIn_{5} in Rotating Magnetic Field.

The d-wave superconductor CeCoIn_{5} has been proposed as a strong candidate for supporting the Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) state near the low-temperature boundary of its upper critical field. Neutron diffraction, however, finds spin-density-wave (SDW) order in this part of the phase diagram for field in the a-b plane, and evidence for the SDW disappears as the applied field is rotated toward the tetragonal c axis. It is important to understand the interplay between the SDW and a possible FFLO state in CeCoIn_{5}, as the mere existence of an SDW does not necessarily exclude an FFLO state. Here, based on a model constructed on the basis of available experiments, we show that an FFLO state competes with an SDW phase. The SDW state in CeCoIn_{5} is stabilized when the field is directed close to the a-b plane. When the field is rotated toward the c axis, the FFLO state emerges, and the SDW phase disappears. In the FFLO state, the nodal planes with extra quasiparticles (where the superconducting order parameter is zero) are perpendicular to the field, and in the SDW phase, the quasiparticle density of states is reduced. We test this model prediction by measuring heat transported by normal quasiparticles in the superconducting state. As a function of field, we observe a reduction of thermal conductivity for field close to the a-b plane and an enhancement of thermal conductivity when field is close to the c axis, consistent with theoretical expectations. Our modeling and experiments, therefore, indicate the existence of the FFLO state when field is parallel to the c axis.

Reduction of visual acuity decreases capacity to evaluate radiographic image quality.

INTRODUCTION: To determine the impact of reduced visual acuity on the evaluation of a test object and appendicular radiographs. METHODS: Visual acuity was reduced by two different magnitudes using simulation glasses and compared to normal vision (no glasses). During phase one phantom images were produced for the purpose of counting objects by 13 observers and on phase 2 image appraisal of anatomical structures was performed on anonymized radiographic images by 7 observers. The monitors were calibrated (SMPTE RP133 test pattern) and the room lighting was maintained at 7 ± 1 lux. Image display and data on grading were managed using ViewDEX (v.2.0) and the area under the visual grading characteristic (AUCVGC) was calculated using VGC Analyzer (v1.0.2). Inferential statistics were calculated using SPSS. RESULTS: For the evaluation of appendicular radiographs the total interpretation time was longer when visual acuity was reduced with 2 pairs of simulation glasses (15.4 versus 8.9 min). Visual grading analysis showed that observers can lose the ability to detect anatomical and contrast differences when they have a simulated visual acuity reduction, being more challenging to differentiate low contrast details. No simulation glasses, compared to 1 pair gives an AUCVGC of 0.302 (0.280, 0.333), that decreases to 0.197 (0.175, 0.223) when using 2 pairs of glasses. CONCLUSIONS: Reduced visual acuity has a significant negative impact on the evaluation of test objects and clinical images. Further work is required to test the impact of reduced visual acuity on visual search, technical evaluation of a wider range of images as well as pathology detection/characterization performance. IMPLICATIONS FOR PRACTICE: It seems that visual performance needs to be considered to reduce the risks associated with incomplete or incorrect diagnosis. If employers or professional bodies were to introduce regular eye tests into health screening it may reduce the risk of misinterpretation as a result of poor vision.

Comparison of two Meglumine-Diatrizoate based bowel preparations for computed tomography colonography: Comparison of patient symptoms and bowel preparation quality.

INTRODUCTION: To investigate the impact of two Meglumine-Diatrizoate based bowel preparation regimes for computed tomography colonography (CTC) on the patient experience and image quality. METHODS: 100 patients consumed Meglumine-Diatrizoate at 24 h and 12 h prior to the CTC examination. 50 patients followed regime 1 (50:50), 50 ml of Meglumine-Diatrizoate at both 24 and 12 h prior to the examination. 50 patients followed regime 2 (75:25), 75 ml of Meglumine-Diatrizoate at 24 h prior to the examination and 25 ml of Meglumine-Diatrizoate at 12 h prior to the examination. All patients completed a questionnaire to indicate the time of onset of adverse effects and when they were most severe. Five advanced practitioners assessed the image quality in a visual grading study. Visual grading characteristic (VGC) analysis was applied with regime 1 as the reference condition and regime 2 and test condition; test alpha was set at 0.05. RESULTS: Image quality was assessed with successful bowel cleansing as the scoring criteria for the visual grading study. The bowel cleansing as provided by the two Meglumine-Diatrizoate regimes was revealed not to be statistically different, with the area under the VGC curve and 95% confidence intervals 0.487 (0.287, 0.701), p = 0.887. Patients taking the 75:25 bowel preparation experienced a shorter median time to the onset of adverse effects. CONCLUSION: There was no observed difference in Image quality criteria score for the two Meglumine-Diatrizoate based bowel preparation with more predictable adverse effects of Meglumine-Diatrizoate with the 75:25 preparation. IMPLICATIONS FOR PRACTICE: Providing patients with a higher contrast burden 24 h prior to CTC may have a positive impact on the patient experience without compromising image quality.

A systematic review of viewing conditions and monitor specifications in mammography.

OBJECTIVES: The purpose of this systematic review was to establish the current status of recommended monitor specifications and viewing conditions in mammography for image acquisition and reporting rooms. A literature search was completed between August 2018 and March 2019 using ScienceDirect, PubMed, Web of Science and MEDLINE databases. An additional manual search was performed to identify relevant guidelines to support the review. Only articles and guidelines written in English were included. KEY FINDINGS: Results were selected according to the following criteria; articles detailing (i) monitor specification and, (ii) viewing conditions in mammography acquisition and reporting rooms. Twenty-one studies met the inclusion criteria. Six papers described monitor specifications, five described viewing conditions and ten guideline documents were identified from the UK, Europe and the US. Common outcomes were that monitors with 3 or 5 MP resolution seemed to be preferred and at the same time higher illumination levels (>15 lux) were found to decrease the luminance of the monitors and negatively impact the assessment of image quality. Contrary to this, the majority of guideline documents recommended illumination levels above 20 Lux. Finally, there is a lack of guidance for viewing conditions in acquisition rooms. CONCLUSION: This review did not reveal any strong evidence for the proposed room illumination levels in acquisition rooms. In reference to monitors specifications, there is preference for using higher resolution displays (3 and 5 MP) but again, the evidence is not strong. Moreover, variance exists in the guidelines and that promotes inconsistency in mammography departments. IMPLICATIONS FOR PRACTICE: This review highlights the lack of standardised guidelines and the need for further research on the viewing conditions and monitor specifications for the acquisition rooms in mammography.

Electronic and magnetic properties of stoichiometric CeAuBi2.

We report the electronic and magnetic properties of stoichiometric CeAuBi2 single crystals. At ambient pressure, CeAuBi2 orders antiferromagnetically below a Néel temperature (TN ) of 19 K. Neutron diffraction experiments revealed an antiferromagnetic propagation vector τ ^ = [ 0 , 0 , 1 ∕ 2 ] , which doubles the paramagnetic unit cell along the c axis. At low temperatures several metamagnetic transitions are induced by the application of fields parallel to the c axis, suggesting that the magnetic structure of CeAuBi2 changes as a function of field. At low temperatures, a linear positive magnetoresistance may indicate the presence of band crossings near the Fermi level. Finally, the application of external pressure favors the antiferromagnetic state, indicating that the 4f electrons become more localized.

Magnetic field-tuned Fermi liquid in a Kondo insulator.

Kondo insulators are expected to transform into metals under a sufficiently strong magnetic field. The closure of the insulating gap stems from the coupling of a magnetic field to the electron spin, yet the required strength of the magnetic field-typically of order 100 T-means that very little is known about this insulator-metal transition. Here we show that Ce[Formula: see text]Bi[Formula: see text]Pd[Formula: see text], owing to its fortuitously small gap, provides an ideal Kondo insulator for this investigation. A metallic Fermi liquid state is established above a critical magnetic field of only [Formula: see text] 11 T. A peak in the strength of electronic correlations near [Formula: see text], which is evident in transport and susceptibility measurements, suggests that Ce[Formula: see text]Bi[Formula: see text]Pd[Formula: see text] may exhibit quantum criticality analogous to that reported in Kondo insulators under pressure. Metamagnetism and the breakdown of the Kondo coupling are also discussed.

Learning to look: Evaluating the student experience of an interactive image appraisal activity.

INTRODUCTION: Student radiographers have expressed difficulty in performing image appraisal tasks. The purpose of this study was to investigate the value of a workshop delivered to level 4 undergraduate students. All students completed an image appraisal activity, inputting their appraisal into software that displayed their response alongside an expert opinion. They were asked to identify and discuss any discrepancy. METHODS: All Level 4 students participated in an image appraisal workshop and were subsequently invited to take part in a focus group immediately after the activity. Twenty-three students took part in three focus groups (n = 7; n = 8; n = 8). A thematic analysis of transcripts was performed alongside validation from observations during the image appraisal activity. RESULTS: Findings demonstrate that despite teaching and resources being available, students had focused on learning a generic checklist for image appraisal, had not appreciated the application of projection specific criteria and felt underprepared. The use of specific criteria and repetition within the task was considered useful. They identified learning needs and misconceptions through peer discussion and via the expert opinion, highlighting the value of feedback. Students enjoyed the workshop and made suggestions for implementation into the curriculum. CONCLUSION: Educators must not assume that the provision of resources will result in students developing deep knowledge. Teaching and learning strategies that are task specific are recommended to avoid a surface approach to learning. Time, repetition and appropriate feedback are essential to enable learners to develop competence and confidence for complex visual tasks, such as image appraisal.

Narrow-Line Cooling and Imaging of Ytterbium Atoms in an Optical Tweezer Array.

Engineering controllable, strongly interacting many-body quantum systems is at the frontier of quantum simulation and quantum information processing. Arrays of laser-cooled neutral atoms in optical tweezers have emerged as a promising platform because of their flexibility and the potential for strong interactions via Rydberg states. Existing neutral atom array experiments utilize alkali atoms, but alkaline-earth atoms offer many advantages in terms of coherence and control, and also open the door to new applications in precision measurement and time keeping. In this Letter, we present a technique to trap individual alkaline-earth-like ytterbium (Yb) atoms in optical tweezer arrays. The narrow ^{1}S_{0}-^{3}P_{1} intercombination line is used for both cooling and imaging in a magic-wavelength optical tweezer at 532 nm. The low Doppler temperature allows for imaging near the saturation intensity, resulting in a very high atom detection fidelity. We demonstrate the imaging fidelity concretely by observing rare (<1 in 10^{4} images) spontaneous quantum jumps into and out of a metastable state. We also demonstrate stochastic loading of atoms into a two-dimensional, 144-site tweezer array. This platform will enable advances in quantum information processing, quantum simulation, and precision measurement. The demonstrated narrow-line Doppler imaging may also be applied in tweezer arrays or quantum gas microscopes using other atoms with similar transitions, such as erbium and dysprosium.

Quantum Oscillations in Flux-Grown SmB_{6} with Embedded Aluminum.

SmB_{6} is a candidate topological Kondo insulator that displays surface conduction at low temperatures. Here, we perform torque magnetization measurements as a means to detect de Haas-van Alphen (dHvA) oscillations in SmB_{6} crystals grown by aluminum flux. We find that dHvA oscillations occur in single crystals containing embedded aluminum, originating from the flux used to synthesize SmB_{6}. Measurements on a sample with multiple, unconnected aluminum inclusions show that aluminum crystallizes in a preferred orientation within the SmB_{6} cubic lattice. The presence of aluminum is confirmed through bulk susceptibility measurements, but does not show a signature in transport measurements. We discuss the ramifications of our results.

Enhanced Hybridization Sets the Stage for Electronic Nematicity in CeRhIn_{5}.

High magnetic fields induce a pronounced in-plane electronic anisotropy in the tetragonal antiferromagnetic metal CeRhIn_{5} at H^{*}≳30 T for fields ≃20° off the c axis. Here we investigate the response of the underlying crystal lattice in magnetic fields to 45 T via high-resolution dilatometry. At low fields, a finite magnetic field component in the tetragonal ab plane explicitly breaks the tetragonal (C_{4}) symmetry of the lattice revealing a finite nematic susceptibility. A modest a-axis expansion at H^{*} hence marks the crossover to a fluctuating nematic phase with large nematic susceptibility. Magnetostriction quantum oscillations confirm a Fermi surface change at H^{*} with the emergence of new orbits. By analyzing the field-induced change in the crystal-field ground state, we conclude that the in-plane Ce 4f hybridization is enhanced at H^{*}, in agreement with the in-plane lattice expansion. We argue that the nematic behavior observed in this prototypical heavy-fermion material is of electronic origin, and is driven by the hybridization between 4f and conduction electrons which carries the f-electron anisotropy to the Fermi surface.