Thermal conductivity of Fe-Si alloys and thermal stratification in Earth's core.

Light elements in Earth's core play a key role in driving convection and influencing geodynamics, both of which are crucial to the geodynamo. However, the thermal transport properties of iron alloys at high-pressure and -temperature conditions remain uncertain. Here we investigate the transport properties of solid hexagonal close-packed and liquid Fe-Si alloys with 4.3 and 9.0 wt % Si at high pressure and temperature using laser-heated diamond anvil cell experiments and first-principles molecular dynamics and dynamical mean field theory calculations. In contrast to the case of Fe, Si impurity scattering gradually dominates the total scattering in Fe-Si alloys with increasing Si concentration, leading to temperature independence of the resistivity and less electron-electron contribution to the conductivity in Fe-9Si. Our results show a thermal conductivity of ∼100 to 110 W⋅m-1⋅K-1 for liquid Fe-9Si near the topmost outer core. If Earth's core consists of a large amount of silicon (e.g., > 4.3 wt %) with such a high thermal conductivity, a subadiabatic heat flow across the core-mantle boundary is likely, leaving a 400- to 500-km-deep thermally stratified layer below the core-mantle boundary, and challenges proposed thermal convection in Fe-Si liquid outer core.

Laparoscopic Lumen-guided cholecystectomy in face of the difficult gallbladder.

BACKGROUND: Where the critical view of safety cannot be established during cholecystectomy, certain salvage techniques are indicated to reduce the likelihood of bile duct injury. The present study describes a salvage technique termed the "laparoscopic lumen-guided cholecystectomy" (LLC) and reports its peri-operative outcomes. METHOD: A summary of the technique is as follows: (1) Hartmann's pouch is incised and stones are evacuated; (2) the cystic anatomy is inspected from the inside of the gallbladder; (3) the lumen is used to guide retrograde dissection towards the cystic pedicle; (4) cystic duct control is achieved if deemed safe. LLC cases performed between June 2020 and January 2022 in a single health board were included. The operative details and peri-operative outcomes of the technique are reported and compared to cases of similar difficulty where the LLC was not attempted. RESULTS: LLC was performed in 4.6% (27/587) of cases. In all 27 cases, LLC was performed for a "frozen" cholecystohepatic triangle. Hartmann's pouch was completely excised in all cases (27/27) and cystic duct control was achieved in 85.2% of cases (23/27). No cases of bile leak or ductal injury were reported. Rates of bile leak, post-operative complications and ERCP were lower following LLC compared to the group where LLC was not attempted (p < 0.01). CONCLUSION: LLC is a safe salvage technique and should be considered in cases where the critical view of safety cannot be established. The technique achieves cystic duct control in the majority of cases and favourable outcomes in the face of a difficult cholecystectomy.

Does participation in the European Trauma Course lead to new behaviours and organisational change? A Portuguese experience.

BACKGROUND: Medical educational courses can be successful from an immediate feedback perspective but not lead to new behaviour or organisational changes in the workplace. The aim of this study was to assess the self-perceived impact of the European Trauma Course (ETC) on Reanima trainees' behaviour and organisational change. METHODS: A 40-item questionnaire based on Holton's evaluation model was used to evaluate the candidate's perceptions. The results were analysed with descriptive and inferential statistical analysis using nonparametric tests with α = 0.05. RESULTS: Out of 295 participants, 126 responded to the survey. Of these, 94% affirmed that the ETC modified their approach to trauma patients, and 71.4% described a change in their behaviour. Postcourse responders changed their behaviour in their initial approach to trauma care in the nontechnical skills of communication, prioritisation and teamwork. Being an ETC instructor strongly influenced the acquisition of new material, and this group was able to implement changes in attitudes. Individuals with no previous trauma course experience identified lack of self-efficacy as a significant obstacle to introducing new work-based learning. In contrast, responders with ATLS training noted a lack of ETC colleagues as the main impediment for moving from conceptualisation to experimentation in the workplace. CONCLUSIONS: Participation in the ETC led to behavioural changes in the workplace. However, the ability to influence others and bring about wider organisational changes was more difficult to achieve. Major factors were the status of the person, their experience and self-efficacy. National organisational impact was obtained, which went far beyond our aspirations in acknowledging change in individual daily practice. Future research studies will include the effect of implementing the ETC methodology on the outcome of trauma patients.

The definite risks and questionable benefits of liberal pre-hospital spinal immobilisation.

INTRODUCTION: The routine practice of pre-hospital spinal immobilisation (phSI) for patients with suspected spinal injury has existed for decades. However, the controversy surrounding it resulted in the 2013 publication of a Consensus document by the Faculty of Pre-Hospital Care. The question remains as to whether the quality of evidence in the literature is sufficient to support the Consensus guidelines. This critical review aims to determine the validity of current recommendations by balancing the potential benefits and side effects of phSI. METHOD: A review of the literature was carried out by two independent assessors using Medline, PubMed, EMBASE and the Cochrane Library databases. Manual searches of related journals and reference lists were also completed. The selected body of evidence was subsequently appraised using a checklist derived from SIGN and CASP guidelines, as well as Crombie's guide to critical appraisal. RESULTS: No reliable sources were found proving the benefit for patient immobilisation. In contrast there is strong evidence to show that pre-hospital spinal immobilisation is not benign with recognised complications ranging from discomfort to significant physiological compromise. The published literature supports the Consensus guideline recommendations for safely reducing the impact of these side effects without compromising the patient. CONCLUSION: The literature supports the Consensus Guidelines but raises the question as to whether they go far enough as there is strong evidence to suggest phSI is an inherently harmful procedure without having any proven benefit. These results demonstrate an urgent need for further studies to determine its treatment effect.

A practical approach to Events Medicine provision.

In the past three decades, mass casualty incidents have occurred worldwide at multiple sporting events and other mass gatherings. Organisational safety and healthcare provision can consequently be scrutinised post-event. Within the UK, such incidents in the 1980s provided incentives to improve medical services and subsequent high profile UK-based international sporting events (London Olympics and Paralympics 2012, Glasgow Commonwealth Games 2014, Rugby World Cup 2015) added a further catalyst for developing services. Furthermore in the aftermath of the abandoned France versus Germany association football match at the Stade de France (Paris Terrorist Attacks, November 2015) and the 2016 UK report from HM Coroner on the Hillsborough Inquest, medical cover at sporting events is being further reviewed. Doctors providing spectator cover therefore need to have an awareness of their likely roles at sporting venues. Formal guidance exists in many countries for the provision of such cover but remains generic even though Events Medicine is increasingly recognised as a necessary service. The current evidence base is limited with best practice examples often anecdotally cited by acute care specialists (eg, emergency medicine) who provide cover. This article is therefore intended to present an overview for doctors of the knowledge and skills required to treat ill and injured spectators and enable them to adequately risk-assess venues in cooperation with other health and safety providers, including preparation for a major incident. It also gives guidance on how activity can be adequately assessed and how doctors can have management roles in Events Medicine.

Towards evidence based emergency medicine: best BETs from the Manchester Royal Infirmary. BET 1: Brachial arterial blood sampling: safe or not?

A shortcut review was carried out to establish whether brachial artery puncture is safe in patients requiring arterial blood sampling. 47 papers were found using the reported searches, of which one presented the best evidence to answer the clinical question. The author, date and country of publication, patient group studied, study type, relevant outcomes, results and study weaknesses of this paper are tabulated. It is concluded that brachial artery puncture is likely to be safe in the non-shocked patient who is not on concurrent anticoagulant therapy.

Sustaining recovery through the night: impact of a peer-run warm line.

OBJECTIVE: This exploratory study describes the impact of a peer-run warm line on the lives of individuals with psychiatric disabilities. METHODS: Phone surveys were completed with 480 warm line callers over four years. RESULTS: Warm line callers reported a reduction in the use of crisis services and a reduction of feelings of isolation. CONCLUSIONS AND IMPLICATIONS FOR PRACTICE: The results indicate that peer-run warm lines can fill an important void in the lives of individuals living with mental illnesses. Although warm lines at any time of day are helpful, keeping warm lines running after 5pm and throughout the night provides support services not typically available after office hours and can assist with loneliness, symptom management, and the process of recovery. Warm lines staffed with appropriately trained, clinically supervised, compensated peer specialists can help round out mental health services in rural and urban communities. Future research should focus on the various implementation and funding options of this unique peer support service.

Melting and density of MgSiO3 determined by shock compression of bridgmanite to 1254GPa.

The essential data for interior and thermal evolution models of the Earth and super-Earths are the density and melting of mantle silicate under extreme conditions. Here, we report an unprecedently high melting temperature of MgSiO3 at 500 GPa by direct shockwave loading of pre-synthesized dense MgSiO3 (bridgmanite) using the Z Pulsed Power Facility. We also present the first high-precision density data of crystalline MgSiO3 to 422 GPa and 7200 K and of silicate melt to 1254 GPa. The experimental density measurements support our density functional theory based molecular dynamics calculations, providing benchmarks for theoretical calculations under extreme conditions. The excellent agreement between experiment and theory provides a reliable reference density profile for super-Earth mantles. Furthermore, the observed upper bound of melting temperature, 9430 K at 500 GPa, provides a critical constraint on the accretion energy required to melt the mantle and the prospect of driving a dynamo in massive rocky planets.

Neurobehavioral and neurodevelopmental profiles of a heuristic genetic model of differential schizophrenia- and addiction-relevant features: The RHA vs. RLA rats.

The Roman High- (RHA) and Low-(RLA) avoidance rat lines/strains were generated through bidirectional selective breeding for rapid (RHA) vs. extremely poor (RLA) two-way active avoidance acquisition. Compared with RLAs and other rat strains/stocks, RHAs are characterized by increased impulsivity, deficits in social behavior, novelty-induced hyper-locomotion, impaired attentional/cognitive abilities, vulnerability to psychostimulant sensitization and drug addiction. RHA rats also exhibit decreased function of the prefrontal cortex (PFC) and hippocampus, increased functional activity of the mesolimbic dopamine system and a dramatic deficit of central metabotropic glutamate-2 (mGlu2) receptors (due to a stop codon mutation at cysteine 407 in Grm2 -cys407*-), along with increased density of 5-HT2A receptors in the PFC, alterations of several synaptic markers and increased density of pyramidal "thin" (immature) dendrític spines in the PFC. These characteristics suggest an immature brain of RHA rats, and are reminiscent of schizophrenia features like hypofrontality and disruption of the excitation/inhibition cortical balance. RHA rats represent a promising heuristic model of neurodevelopmental schizophrenia-relevant features and comorbidity with drug addiction vulnerability.

A multilayered approach to complex surface patterning.

A method for developing complex nanopatterns on surfaces has been developed by combining self-assembly, photolabile protecting groups, and multilayered films. An o-nitrobenzyl protecting group has been incorporated into molecular level films utilizing thiol-gold interactions. When the o-nitrobenzyl group is cleaved by ultraviolet light, a carboxylic acid terminated layer remains on the surface and is available for activation and further functionalization through amide bond formation. Using this method, multilayered films have been constructed and characterized by contact angle goniometry, cyclic voltammetry, grazing incidence infrared spectroscopy, and X-ray photoelectron spectroscopy measurements. Complex surface patterns can be achieved by creating a surface array using a photomask and then further functionalizing the irradiated area through covalent coupling. Fluorophores were attached to the deprotected regions, providing visual evidence of surface patterning using fluorescence microscopy. This approach is universal to bind moieties containing free amine groups at defined regions across a surface, allowing for the development of films with complex chemical and physicochemical properties.

'Effectiveness of Continuing Professional Development' project: a summary of findings.

This article reports on a study examining continuing professional development (CPD) for consultant doctors. The aim of the study was to identify what promotes or inhibits the effectiveness of CPD and met the following objectives: comparing and contrasting the experiences of CPD across the range of specialties; identifying and describing the range of different models of CPD employed across the different specialties and clinical contexts; considering the educational potential of reflective practice in CPD and its impact on professional practice and exploring how different professionals judge the effectiveness of current CPD practices. Using a mixture of qualitative (interviews, letters, observation) and quantitative (online questionnaire) methods, the views of CPD providers and users were surveyed. Findings suggested that the effectiveness of CPD, as inferred from the comments made by interviewees and questionnaire respondents, relates to the impact on knowledge, skills, values, attitudes, behaviours and changes in practice in the work place. The quality of CPD was seen as inextricably linked to any improvements in the quality of the professional practices required for service delivery. There was widespread consensus as to the value of learning in professional settings. There was recognition that there needs to be a move away from tick boxes to the in-depth identification of learning needs and how these can be met both within and external to the work place, with learning being adequately enabled and assessed in all locations. In conclusion, it can be said that CPD is valued and is seen as effective when it addresses the needs of individual clinicians, the populations they serve and the organisations within which they work. However, the challenge for CPD may lie in the dynamic interaction between educational opportunities and service delivery requirements, as there may be occasions where they vie with each other for resources.

Effect of electrode roughness on the capacitive behavior of self-assembled monolayers.

Analytical gold electrodes were polished mechanically and electrochemically and the true area of the electrode surface was measured by quantitative oxidative/reductive cycling of the electrode. A roughness factor for each electrode was determined from the ratio of the true area to the geometric area. The roughness is fully described by a combination of microscopic roughness (up to tens of nanometers) and macroscopic roughness (on the order of hundreds of nanometers) terms. The electrodes were then derivatized with a self-assembled monolayer (SAM) of dodecanethiol or a thioalkane azacrown and characterized by impedance spectroscopy. The behavior of the electrodes was modeled with either a Helmholtz or Randles equivalent circuit (depending on the SAM used) in which the capacitance was replaced with a constant phase element. From the model, an effective capacitance and an alpha factor that quantifies the nonideality of the SAM capacitance was obtained. The effective capacitance divided by the roughness factor yields the capacitance per unit true area, which is only a function of microscopic roughness. The relationship between this capacitance and the alpha factor indicates that microscopic roughness predominantly affects the nonideality of the film while macroscopic roughness predominantly affects the magnitude of the film's capacitance. Understanding the contribution of the electrode topography to the magnitude and ideality of the SAM capacitance is important in the construction of SAM-based capacitive sensors because it predicts the importance of electrode-electrode variations.

13C NMR study of the ion-binding selectivity of a new ammonium ionophore.

A bicyclic peptide, cyclo (L-Glu(1)-D-Leu(2)-Aib(3)-L-Lys(4)-D-Leu(5)-D-Ala(6))-cyclo-(1gamma-4epsilon) (I), was designed and synthesized to provide an ammonium ion complexation site in a tetrahedral geometry. Molecular modeling, dynamics and electrostatic studies for I indicated that it exhibits some selectivity for ammonium ions over potassium and sodium ions. NMR measurements in CDCl(3)/CD(3)OD (1:1) show that for those carbonyl groups involved in cation binding, (13)C resonances shifted downfield with increasing cation concentration. The resonance that exhibited the largest change in chemical shift between uncomplexed and complexed forms was used to determine the selectivity. Selectivity values obtained were logK(NH(4) (+), Na(+) ) = - 2.4 and logK(NH(4) (+), K(+) ) = - 0.6.

Late malignant change in an ileal conduit.

Around 3000 bowel segment transpositions are performed in the UK each year and although malignancy is well-recognized following ureterosigmoidostomy, reports of similar changes in ileal conduits are sparse. We report a case of ileal adenocarcinoma in a 67-year-old lady some 49 years after ileal conduit, demonstrating previously unassociated histopathological features similar to those seen in collagenous colitis.

'Catching' the concept of spiritual care: implementation of an education programme.

This article will outline the achievements of a project group as they translate the recommendations set out in the UK National Institute for Health and Clinical Excellence (NICE) guidance on spiritual care provision in clinical practice (NICE, 2004). It was evident that there was an opportunity to offer a comprehensive, competency-based course that developed recognition of the spiritual care needs of patients with cancer and their carers. A two-day experiential programme was devised that included role play, the evidence base, theory and fun, resulting in the acquisition of tacit and explicit knowledge. The course was based around the following tenets: Spiritual issues are broader than religious ones and include a quest for meaning in the illness, resolution of old conflicts and integration of past life experiences (Barraclough, 1994). We cannot know others except by knowing ourselves (Carrither, 1992). It is hoped that by providing holistic training that stimulates the growth of an individual's spirituality and allows them to identify their spiritual needs, we can increase understanding, awareness, confidence and knowledge in ways that can have a real application within the workplace, enabling spiritual care provision to become realistically integral to care.

The Habitability of Proxima Centauri b: Environmental States and Observational Discriminants.

Proxima Centauri b provides an unprecedented opportunity to understand the evolution and nature of terrestrial planets orbiting M dwarfs. Although Proxima Cen b orbits within its star's habitable zone, multiple plausible evolutionary paths could have generated different environments that may or may not be habitable. Here, we use 1-D coupled climate-photochemical models to generate self-consistent atmospheres for several evolutionary scenarios, including high-O2, high-CO2, and more Earth-like atmospheres, with both oxic and anoxic compositions. We show that these modeled environments can be habitable or uninhabitable at Proxima Cen b's position in the habitable zone. We use radiative transfer models to generate synthetic spectra and thermal phase curves for these simulated environments, and use instrument models to explore our ability to discriminate between possible planetary states. These results are applicable not only to Proxima Cen b but to other terrestrial planets orbiting M dwarfs. Thermal phase curves may provide the first constraint on the existence of an atmosphere. We find that James Webb Space Telescope (JWST) observations longward of 10 µm could characterize atmospheric heat transport and molecular composition. Detection of ocean glint is unlikely with JWST but may be within the reach of larger-aperture telescopes. Direct imaging spectra may detect O4 absorption, which is diagnostic of massive water loss and O2 retention, rather than a photosynthetic biosphere. Similarly, strong CO2 and CO bands at wavelengths shortward of 2.5 µm would indicate a CO2-dominated atmosphere. If the planet is habitable and volatile-rich, direct imaging will be the best means of detecting habitability. Earth-like planets with microbial biospheres may be identified by the presence of CH4-which has a longer atmospheric lifetime under Proxima Centauri's incident UV-and either photosynthetically produced O2 or a hydrocarbon haze layer. Key Words: Planetary habitability and biosignatures-Planetary atmospheres-Exoplanets-Spectroscopic biosignatures-Planetary science-Proxima Centauri b. Astrobiology 18, 133-189.

HIV infection is associated with an increased risk for lung cancer, independent of smoking.

BACKGROUND: Human immunodeficiency virus (HIV)-infected persons have an elevated risk for lung cancer, but whether the increase reflects solely their heavy tobacco use remains an open question. METHODS: The Acquired Immunodeficiency Syndrome (AIDS) Link to the Intravenous Experience Study has prospectively observed a cohort of injection drug users in Baltimore, Maryland, since 1988, using biannual collection of clinical, laboratory, and behavioral data. Lung cancer deaths were identified through linkage with the National Death Index. Cox proportional hazards regression was used to examine the effect of HIV infection on lung cancer risk, controlling for smoking status, drug use, and clinical variables. RESULTS: Among 2086 AIDS Link to the Intravenous Experience Study participants observed for 19,835 person-years, 27 lung cancer deaths were identified; 14 of the deaths were among HIV-infected persons. All but 1 (96%) of the patients with lung cancer were smokers, smoking a mean of 1.2 packs per day. Lung cancer mortality increased during the highly active antiretroviral therapy era, compared with the pre-highly active antiretroviral therapy period (mortality rate ratio, 4.7; 95% confidence interval, 1.7-16). After adjusting for age, sex, smoking status, and calendar period, HIV infection was associated with increased lung cancer risk (hazard ratio, 3.6; 95% confidence interval, 1.6-7.9). Preexisting lung disease, particularly noninfectious diseases and asthma, displayed trends for increased lung cancer risk. Illicit drug use was not associated with increased lung cancer risk. Among HIV-infected persons, smoking remained the major risk factor; CD4 cell count and HIV load were not strongly associated with increased lung cancer risk, and trends for increased risk with use of highly active antiretroviral therapy were not significant. CONCLUSIONS: HIV infection is associated with significantly increased risk for developing lung cancer, independent of smoking status.

The European Trauma Course--from concept to course.

The Advanced Trauma Life Support (ATLS) course, developed by the American College of Surgeons, has revolutionised in-hospital management of major trauma patients and is now accepted as a standard of care in many countries worldwide. However, within Europe, there are significant differences in both the aetiology of trauma and the specialties involved in its initial management compared to the American model. Over the past 4 years, there have been a number of initiatives aimed at producing a trauma management course that was evidence based, practical and flexible enough to meet regional European needs and team oriented. Initial attempts tried to incorporate both pre- and in-hospital trauma care. This was eventually rationalised to the production of an in-hospital course and the first pilot course was run in Malta in November 2006. This article describes the evolution of the course, its current structure and plans for the future following the feedback received from candidates and instructors who participated in the first course.

The quiet servant.

Chaplains have been involved in health care for hundreds of years. St Bartholomew's Hospital, in London, for example, was founded in 1123 by Rahere, a favourite courtier of Henry I who had taken monastic vows and who became the first prior of the hospital, managing the monks who cared for its patients.

Inter-individual vs line/strain differences in psychogenetically selected Roman High-(RHA) and Low-(RLA) Avoidance rats: neuroendocrine and behavioural aspects.

Inter-individual differences in neuroendocrine and behavioural responses to environmental challenges will be considered within the context of psychogenetic selection, using the Roman High-(RHA) and Low-(RLA) Avoidance rat lines as an example. We assume that the selected genotypes, by interacting with environmental factors, determine specific 'biobehavioural profiles'. Practical and theoretical problems regarding the measurement of inter-individual vs line/strain differences, the definition of 'traits' vs experimental variables, and possible correlations between physiological and behavioural parameters will be discussed. We will argue that environmental influences are the main cause of inter-individual variability, and that the genotype only constitutes a 'blueprint' from which typical biobehavioural profiles are established, notably under the influence of early environmental factors. These biobehavioural profiles may correspond in part to human categories known as 'types', 'temperaments' or 'personality traits'. Within each category (including those which can be obtained by psychogenetic selection), more individual personality traits can evolve, notably as a result of social interactions and particular life events.