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In unconventional superconductors, coupled charge and lattice degrees of freedom can manifest in ordered phases of matter that are intertwined. In the cuprate family, fluctuating short-range charge correlations can coalesce into a longer-range charge density wave (CDW) order which is thought to intertwine with superconductivity, yet the nature of the interaction is still poorly understood. Here, by measuring subtle lattice fluctuations in underdoped YBa 2 Cu 3 O 6+ y on quasi-static timescales (thousands of seconds) through X-ray photon correlation spectroscopy, we report sensitivity to both superconductivity and CDW. The atomic lattice shows remarkably faster relaxational dynamics upon approaching the superconducting transition at T c ≈ 65 K. By tracking the momentum dependence, we show that the intermediate scattering function almost monotonically scales with the relaxation distance of atoms away from their average positions above T c and in the presence of the CDW state, while this peculiar trend is reversed for other temperatures. These observations are consistent with an incipient CDW stabilized by local strain. This work provides insights into the crucial role of relaxational atomic fluctuations for understanding the electronic physics cuprates, which are inherently disordered due to carrier doping., Competing Interests: Competing interests statement:The authors declare no competing interest.

The kagome superconductor CsV 3 Sb 5 hosts a variety of charge density wave (CDW) phases, which play a fundamental role in the formation of other exotic electronic instabilities. However, identifying the precise structure of these CDW phases and their intricate relationships remain the subject of intense debate, due to the lack of static probes that can distinguish the CDW phases with identical spatial periodicity. Here, we unveil the out-of-equilibrium competition between two coexisting 2 × 2 × 2 CDWs in CsV 3 Sb 5 harnessing time-resolved X-ray diffraction. By analyzing the light-induced changes in the intensity of CDW superlattice peaks, we demonstrate the presence of both phases, each displaying a significantly different amount of melting upon excitation. The anomalous light-induced sharpening of peak width further shows that the phase that is more resistant to photo-excitation exhibits an increase in domain size at the expense of the other, thereby showcasing a hallmark of phase competition. Our results not only shed light on the interplay between the multiple CDW phases in CsV 3 Sb 5 , but also establish a non-equilibrium framework for comprehending complex phase relationships that are challenging to disentangle using static techniques., (© 2024. The Author(s).)

Sr 2 IrO 4 has attracted considerable attention due to its structural and electronic similarities to La 2 CuO 4 , the parent compound of high- T c superconducting cuprates. It was proposed as a strong spin-orbit-coupled J eff = 1/2 Mott insulator, but the Mott nature of its insulating ground state has not been conclusively established. Here, we use ultrafast laser pulses to realize an insulator-metal transition in Sr 2 IrO 4 and probe the resulting dynamics using time- and angle-resolved photoemission spectroscopy. We observe a gap closure and the formation of weakly renormalized electronic bands in the gap region. Comparing these observations to the expected temperature and doping evolution of Mott gaps and Hubbard bands provides clear evidence that the insulating state does not originate from Mott correlations. We instead propose a correlated band insulator picture, where antiferromagnetic correlations play a key role in the gap opening. More broadly, our results demonstrate that energy-momentum-resolved nonequilibrium dynamics can be used to clarify the nature of equilibrium states in correlated materials., Competing Interests: Competing interests statement:The authors declare no competing interest.

Competing Interests: TL has received an honorarium for a lecture on this topic from Al Sultan United Medical Co and is head of clinical artificial intelligence at Bradford Teaching Hospitals NHS Foundation Trust, and a potential liability sink All other authors report no conflicts of interest

Reducing floor eggs in cage-free (CF) housing systems is among primary concerns for egg producers. The objective of this research was to evaluate the effects of ground robot manipulation on reduction of floor eggs. In addition, the effects of ground robot manipulation on production performance, stress response, bone quality, and behavior were also investigated. Two successive flocks of 180 Hy-Line Brown hens at 34 weeks of this age were used. The treatment structure for each flock consisted of six pens with three treatments (without robot running, with one-week robot running, and with two-weeks robot running), resulting in two replicates per treatment per flock and four replicates per treatment with two flocks. Two phases were involved with each flock. Phase 1 (weeks 35-38) mimicked the normal scenario, and phase 2 (weeks 40-43) mimicked a scenario after inadvertent restriction to nest box access. Results indicate that the floor egg reduction rate in the first two weeks of phase 1 was 11.0% without the robot treatment, 18.9% with the one-week robot treatment, and 34.0% with the two-week robot treatment. The effect of robot operation on floor egg production was not significant when the two phases of data were included in the analysis. Other tested parameters were similar among the treatments, including hen-day egg production, feed intake, feed conversion ratio, live body weight, plasma corticosterone concentration, bone breaking force, ash percentage, and time spent in nest boxes. In conclusion, ground robot operation in CF settings may help to reduce floor egg production to a certain degree for a short period right after being introduced. Additionally, robot operation does not seem to negatively affect hen production performance and well-being., Competing Interests: The authors have declared that no competing interests exist.

Correlated oxides can exhibit complex magnetic patterns. Understanding how magnetic domains form in the presence of disorder and their robustness to temperature variations has been of particular interest, but atomic scale insight has been limited. We use spin-polarized scanning tunneling microscopy to image the evolution of spin-resolved modulations originating from antiferromagnetic (AF) ordering in a spin-orbit Mott insulator perovskite iridate Sr 3 Ir 2 O 7 as a function of chemical composition and temperature. We find that replacing only several percent of lanthanum for strontium leaves behind nanometer-scale AF puddles clustering away from lanthanum substitutions preferentially located in the middle strontium oxide layer. Thermal erasure and reentry into the low-temperature ground state leads to a spatial reorganization of the AF puddles, which nevertheless maintain scale-invariant fractal geometry in each configuration. Our experiments reveal multiple stable AF configurations at low temperature and shed light onto spatial fluctuations of the AF order around atomic scale disorder in electron-doped Sr 3 Ir 2 O 7 .

In recent years, several new technical methods have been developed to make AI-models more transparent and interpretable. These techniques are often referred to collectively as 'AI explainability' or 'XAI' methods. This paper presents an overview of XAI methods, and links them to stakeholder purposes for seeking an explanation. Because the underlying stakeholder purposes are broadly ethical in nature, we see this analysis as a contribution towards bringing together the technical and ethical dimensions of XAI. We emphasize that use of XAI methods must be linked to explanations of human decisions made during the development life cycle. Situated within that wider accountability framework, our analysis may offer a helpful starting point for designers, safety engineers, service providers and regulators who need to make practical judgements about which XAI methods to employ or to require. This article is part of the theme issue 'Towards symbiotic autonomous systems'.

Objectives The importance of personalized and dignified care is increasingly being recognized in health care policy and practice. Despite the known impact of clothing on social identity and self-expression, the impact of hospital clothing on patient well-being has been widely overlooked. Patients are often required to wear hospital clothing, commonly a backless gown, during medical procedures and surgeries. The impact of wearing patient clothing on well-being, during this time of vulnerability, was explored. Design A sequential multi-method approach consisting of two studies. Methods Two studies were carried out to consider the impact of the hospital gown on well-being among adults with and without chronic health conditions. The first study consisted of conducting in-depth, semi-structured interviews (n = 10) with adults living with a lifelong chronic health condition (congenital heart disease). The second study was a cross-sectional online survey exploring adults' views (n = 928) and experiences of wearing the hospital gown. Results Qualitative analysis identified the following master themes: (1) symbolic embodiment of the 'sick' role, (2) relinquishing control to medical professionals, and (3) emotional and physical vulnerability. Quantitative analysis of the online survey data indicated that adults often reported wearing the hospital gown despite a lack of medical necessity. Its design was considered to be not fit for purpose and lacking in dignity. Conclusions The implications of these findings for health policy and practice are discussed, emphasizing the importance of challenging cultural norms in health care since dehumanizing aspects of care, as symbolically represented by the hospital gown, may adversely impact on patient well-being. Statement of contribution What is already known Getting dressed is a form of self-expression, which contributes to the construction of social identity, yet few studies have explored the impact of wearing hospital clothing on patient well-being. The few studies on hospital clothing that exist suggest it is predominantly associated with feeling depersonalized, stigmatized, and devitalized, being in the 'patient role', low status, and a lack of control and privacy. However, previous studies include a variety of hospital clothing including pyjamas (Edvardsson, 2009) and dressing gowns (Topo & Iltanen-Tähkävuori, 2010), whereas in the United Kingdom, a 'one-size-fits-all' backless gown, held together with ties at the back, is most commonly used. What this study adds This study furthers understanding about the lived experience of wearing hospital clothing for people living with a chronic health condition (congenital heart disease) and without. Wearing hospital clothing (most commonly the hospital gown) was associated with symbolic embodiment of the 'sick' role, relinquishing control to medical professionals, and emotional and physical vulnerability for people living with a chronic health condition. Findings from a wider sample, drawn from the general population, suggest that the hospital gown is often being used despite a lack of medical necessity often leaving patients feeling exposed, self-conscious, vulnerable, uncomfortable, cold, embarrassed, and disempowered. These findings are exacerbated for people living with a long-term health condition and women. Together, these studies suggest that the current design of the hospital gown is not fit for purpose and impacts negatively on patient well-being., (© 2020 The Authors. British Journal of Health Psychology published by John Wiley & Sons Ltd on behalf of British Psychological Society.)

We used a combination of polarized Raman spectroscopy and spin wave calculations to study magnetic excitations in the strong spin-orbit-coupled bilayer perovskite antiferromagnet Sr_{3}Ir_{2}O_{7}. We observed two broad Raman features at ∼800 and ∼1400  cm^{-1} arising from magnetic excitations. Unconventionally, the ∼800  cm^{-1} feature is fully symmetric (A_{1g}) with respect to the underlying tetragonal (D_{4h}) crystal lattice which, together with its broad line shape, definitively rules out the possibility of a single magnon excitation as its origin. In contrast, the ∼1400  cm^{-1} feature shows up in both the A_{1g} and B_{2g} channels. From spin wave and two-magnon scattering cross-section calculations of a tetragonal bilayer antiferromagnet, we identified the ∼800  cm^{-1} (1400  cm^{-1}) feature as two-magnon excitations with pairs of magnons from the zone-center Γ point (zone-boundary van Hove singularity X point). We further found that this zone-center two-magnon scattering is unique to bilayer perovskite magnets which host an optical branch in addition to the acoustic branch, as compared to their single layer counterparts. This zone-center two-magnon mode is distinct in symmetry from the time-reversal symmetry broken "spin wave gap" and "phase mode" proposed to explain the ∼92  meV (742  cm^{-1}) gap in resonant inelastic x-ray spectroscopy magnetic excitation spectra of Sr_{3}Ir_{2}O_{7}.

Background: Hydrocephalus shunt malfunctions remain treated with surgical intervention only. Despite efforts at identifying or preventing CSF shunt obstruction, no evidence currently exists to restore CSF flow following proximal occlusion, non-invasively., Case Description: We present direct intraoperative evidence in the case of a 5-year-old male who developed hydrocephalus subsequent to hemorrhagic presentation post cerebral arteriovenous malformation rupture. After weeks of externalized CSF diversion for clearance of CSF red blood cells, he was taken to the operating room for removal of the external ventricular drain and placement of a ventriculoperitoneal shunt for hydrocephalus. At conclusion of placing his ventriculoperitoneal shunt with ReFlow flusher assist device, his shunt valve reservoir was noted to not refill. Following manual depression of the ReFlow flusher, we identified clearance of debris from the obstructed ventricular catheter allowing reestablished CSF flow through the shunt system under live intraoperative ultrasonography. Subsequently, there was return of brisk refill to the shunt valve reservoir., Conclusion: Observations here demonstrate a potentially useful technical strategy toward clearance of proximal shunt obstructions, in situ ., Competing Interests: The authors declare an interest in materials presented herein as follows: Dr. Joseph R. Madsen is a Co-Founder of Anuncia and Co-Inventor of the ReFlow Ventricular System. Dr. Sudhakar Vadivelu is a consultant for Alycone lifesciences., (Copyright: © 2020 Surgical Neurology International.)

We report on the evolution of the average and depth-dependent magnetic order in thin-film samples of biaxially stressed and electron-doped EuTiO 3 for samples across a doping range < 0.1 to 7.8 × 10 20 cm -3 . Under an applied in-plane magnetic field, the G -type antiferromagnetic ground state undergoes a continuous spin-flop phase transition into in-plane, field-polarized ferromagnetism. The critical field for ferromagnetism slightly decreases with an increasing number of free carriers, yet the field evolution of the spin-flop transition is qualitatively similar across the doping range. Unexpectedly, we observe interfacial ferromagnetism with saturated Eu 2+ moments at the substrate interface at low fields preceding ferromagnetic saturation throughout the bulk of the degenerate semiconductor film. We discuss the implications of these findings for the unusual magnetotransport properties of this compound.

The prospect of patient harm caused by the decisions made by an artificial intelligence-based clinical tool is something to which current practices of accountability and safety worldwide have not yet adjusted. We focus on two aspects of clinical artificial intelligence used for decision-making: moral accountability for harm to patients; and safety assurance to protect patients against such harm. Artificial intelligence-based tools are challenging the standard clinical practices of assigning blame and assuring safety. Human clinicians and safety engineers have weaker control over the decisions reached by artificial intelligence systems and less knowledge and understanding of precisely how the artificial intelligence systems reach their decisions. We illustrate this analysis by applying it to an example of an artificial intelligence-based system developed for use in the treatment of sepsis. The paper ends with practical suggestions for ways forward to mitigate these concerns. We argue for a need to include artificial intelligence developers and systems safety engineers in our assessments of moral accountability for patient harm. Meanwhile, none of the actors in the model robustly fulfil the traditional conditions of moral accountability for the decisions of an artificial intelligence system. We should therefore update our conceptions of moral accountability in this context. We also need to move from a static to a dynamic model of assurance, accepting that considerations of safety are not fully resolvable during the design of the artificial intelligence system before the system has been deployed., ((c) 2020 The authors; licensee World Health Organization.)

The breakdown of [Formula: see text] antiferromagnetism in the limit of strong disorder is studied in Sr 3 (Ir 1-x Mn x ) 2 O 7 . Upon Mn-substitution, antiferromagnetic ordering of the Ir cations becomes increasingly two-dimensional, resulting in the complete suppression of long-range Ir magnetic order above [Formula: see text]. Long-range antiferromagnetism however persists on the Mn sites to higher Mn concentrations (x  >  0.25) and is necessarily mediated via a random network of majority Ir sites. Our data suggest a shift in the Mn valence from Mn 4+ to Mn 3+ at intermediate doping levels, which in turn generates nonmagnetic Ir 5+ sites and suppresses long-range order within the Ir network. The collapse of long-range [Formula: see text] antiferromagnetism and the survival of percolating antiferromagnetic order on Mn-sites demonstrates a complex 3d-5d exchange process that surprisingly enables minority Mn spins to order far below the conventional percolation threshold for a bilayer square lattice.

The unconventional electronic ground state of Sr&#95;{3}IrRuO&#95;{7} is explored via resonant x-ray scattering techniques and angle-resolved photoemission measurements. As the Ru content approaches x=0.5 in Sr&#95;{3}(Ir&#95;{1-x}Ru&#95;{x})&#95;{2}O&#95;{7}, intermediate to the J&#95;{eff}=1/2 Mott state in Sr&#95;{3}Ir&#95;{2}O&#95;{7} and the quantum critical metal in Sr&#95;{3}Ru&#95;{2}O&#95;{7}, a thermodynamically distinct metallic state emerges. The electronic structure of this intermediate phase lacks coherent quasiparticles, and charge transport exhibits a linear temperature dependence over a wide range of temperatures. Spin dynamics associated with the long-range antiferromagnetism of this phase show nearly local, overdamped magnetic excitations and an anomalously large energy scale of 200 meV-an energy far in excess of exchange energies present within either the Sr&#95;{3}Ir&#95;{2}O&#95;{7} or Sr&#95;{3}Ru&#95;{2}O&#95;{7} solid-solution end points. Overdamped quasiparticle dynamics driven by strong spin-charge coupling are proposed to explain the incoherent spectral features of the strange metal state in Sr&#95;{3}IrRuO&#95;{7}.

Materials that exhibit both strong spin-orbit coupling and electron correlation effects are predicted to host numerous new electronic states. One prominent example is the J eff  = 1/2 Mott state in Sr 2 IrO 4 , where introducing carriers is predicted to manifest high temperature superconductivity analogous to the S = 1/2 Mott state of La 2 CuO 4 . While bulk superconductivity currently remains elusive, anomalous quasiparticle behaviors paralleling those in the cuprates such as pseudogap formation and the formation of a d-wave gap are observed upon electron-doping Sr 2 IrO 4 . Here we establish a magnetic parallel between electron-doped Sr 2 IrO 4 and hole-doped La 2 CuO 4 by unveiling a spin density wave state in electron-doped Sr 2 IrO 4 . Our magnetic resonant X-ray scattering data reveal the presence of an incommensurate magnetic state reminiscent of the diagonal spin density wave state observed in the monolayer cuprate (La 1-x Sr x ) 2 CuO 4 . This link supports the conjecture that the quenched Mott phases in electron-doped Sr 2 IrO 4 and hole-doped La 2 CuO 4 support common competing electronic phases.

A large-scale study ( Forder et al 2012 ) piloting personal health budgets for people with long-term conditions found that they improved patients' quality of life and psychological wellbeing. They were cost-effective and reduced the use of other healthcare services. From April next year, people receiving NHS continuing healthcare funding will have the right to ask for personal health budgets. Some clinical commissioning groups are also introducing them for mental health service users and patients with other long-term conditions. This article outlines the benefits and challenges of introducing personal health budgets, and suggests how nursing managers can begin to consider their role in implementing them.