Differential attainment in higher surgical training: scoping pan-specialty spectra.

INTRODUCTION: This study aimed to evaluate differential attainment during higher surgical training (HST; all specialties) related to three ethnic cohorts: White UK (WUKG), Black and Minority Ethnic UK Graduates (BMEUKG), and International Medical Graduates (IMG). METHOD: Anonymised records of 266 HSTs (126 WUKG, 65 BMEUKG, 75 IMG; 7 years) in a single UK Statutory Education Body were examined. Primary effect measures were Annual Record of Competency Progression Outcome (ARCPO) and Fellowship of the Royal College of Surgeons (FRCS) pass. RESULTS: ARCPOs related to ethnicity and specialty were similar with the exception of general surgery (GS) trainees, four of whom received ARCPO 4 (GS 4.9% (75% BME; p=0.025) vs all other 0%). ARCPO 3 was commoner in women (22/76, (28.9%) than men 27/190 (14.2%), OR 2.46, p=0.006). FRCS pass rates (WUKG vs BMEUKG vs IMG) were 76.9%, 52.9% and 53.9% respectively (p=0.064) but unrelated to gender (M 70.4% vs F 64.3%). On multivariable analyses: ARCPO 3 was associated with Female gender and Maternity Leave (OR 8.05, p=0.001); FRCS pass with ethnicity (OR 0.21, p=0.028) and Hirsch Indices of ≥5 (OR 11.17, p=0.001). CONCLUSION: Differential attainment was plain with BMEUKG FRCS performance almost a third poorer than WUKG, and women twofold more likely to receive adverse ARCPOs, with return from statutory leave independently associated with training extension. Focused counter measures targeted at non-operative technical skills (including academic reach), Keeping in Touch, Return to Work, and re-induction programmed support are urgently needed for trainees at risk.

Unconventional domain wall magnetoresistance of patterned Ni/Nb bilayer structures below superconducting transition temperature of Nb.

Scattering of spin-up and spin-down electrons while passing through a ferromagnetic domain wall (DW) leads to an additional resistance for transport current, usually observed prominently in constricted magnetic structures. In this report we use the resistance of the DW as a probe to find an indirect signatures of the theoretically predicted spin-singlet supercurrent to spin-triplet supercurrent conversion effect of ferromagnetic DWs. Here we examine the DW induced resistance in Ni stripe in a bilayer Ni/Nb geometry in the normal state and in the superconducting state of Nb. By making a 3µm wide gap in the top Nb layer we routed the transport current through the Ni layer in the normal state and in the superconducting state of Nb. In the normal state of Nb, in-field transport measurements showed a clear domain wall magneto-resistance (DWMR) peak of amplitude ∼5.9 mΩ near the coercive field, where the DW density is expected to be maximum. Interestingly, however, below the superconducting transition temperature of Nb, the DWMR peak of the Ni layer showed a sharp drop in the field range where the number of DWs become maximum. This observation may be a possible signature of magnetic DW induced spin-triplet correlations in the Ni layer due to the direct injection of spin-singlet Cooper pairs from Nb into the magnetic DWs.

Nanoscale Domain Wall Engineered Spin-Triplet Josephson Junctions and SQUID.

Spin-singlet Cooper pairs convert to spin-triplet Cooper pairs on passing through a magnetically noncollinear structure at a superconductor(S)/ferromagnet(F) interface. In this context, the generation of triplet supercurrents through intrinsic ferromagnetic domain walls, which are naturally occurring noncollinear magnetic features, was proposed theoretically in the past decade. However, an experimental demonstration has been lacking in the literature, particularly because of the difficulty in accessing a single domain wall, which is typically buried between two domains in a ferromagnetic material. By patterning a ferromagnetic nanoconstriction, we have been able to realize a nanoscale S/F/S planar junction, where a single domain wall (pinned at the nanoconstriction) acts as a Josephson barrier. In this geometry, we are able to show the predicted long-range triplet supercurrent across a ferromagnetic barrier exceeding 70 nm. Using this technique, we have demonstrated a ferromagnetic planar nano-SQUID device consisting of two Nb/Ni/Nb spin-triplet Josephson junctions.

Anaphylactic Reaction Rates to Blue Dyes Used for Sentinel Lymph Node Mapping: Systematic Review and Meta-analysis.

OBJECTIVE: The primary objective of this study was to quantify the risk of anaphylaxis to blue dyes used in SLNB for cancer. Secondary outcomes included the identification of factors that may influence this risk. SUMMARY OF BACKGROUND DATA: Blue dyes are widely used to help identify sentinel lymph nodes in oncological surgery. The rate of severe allergic reactions to blue dyes remains a controversial topic, with the true incidence and influencing factors uncertain. METHODS: A systematic review and meta-analysis was performed to identify all studies which report on the incidence of severe adverse reactions and anaphylaxis to blue dyes (patent blue, isosulfan blue, methylene blue, and indigo carmine), when used for SLNB. Collected data included cancer and dye type, volume, and method of injection. Incidence was estimated using the arcsine method of statistical analysis. RESULTS: One hundred nine studies documenting 94 episodes of anaphylaxis in a total of 61,951 SLNB procedures, resulting in a weighed anaphylaxis rate of 0.061%. SLNB for breast cancer carries an anaphylaxis risk of 0.083%, with the risk markedly lower in melanoma surgery (0.0043%). Low dye volume (<2 mL) and intradermal injection are both associated with lower rates of anaphylaxis (0.031% and 0.0068%). Isosulfan blue seems to be the most anaphylactogenic amongst blue dyes with a rate of 0.16%. There were no reported cases of death in this cohort. CONCLUSION: Anaphylaxis to blue dyes in SLNB is rare. Methylene blue, patent blue, lower dye volumes, and intradermal administration are all associated with a lower incidence of anaphylaxis.

Long-term seizure recurrence after eclampsia: A systematic review and meta-analysis.

BACKGROUND: Seizure recurrence after a fit has implications for both individuals and healthcare providers guiding neurologic prognosis, treatment, and driving and work restrictions. A systematic review of long-term seizure recurrence after eclampsia will help to quantify recurrence risk in this setting. OBJECTIVE: To evaluate the long-term recurrence of seizures after eclampsia. SEARCH STRATEGY: After PROSPERO registration, Medline (Ovid), Embase, and Cochrane Library were searched by using the terms (eclampsia OR eclamp* OR eclamptic seizure* OR eclamptic fit*) AND (recur* OR recurrent fit* OR recurrent seizure*) for studies published up until December 2019. SELECTION CRITERIA: Studies describing long-term seizure recurrence after a diagnosis of eclampsia were included. DATA COLLECTION AND ANALYSIS: Data were extracted from studies independently by two authors. Pooled prevalence was calculated and weighted based on sample size with a 95% confidence interval (CI). MAIN RESULTS: Initially, 1754 unique studies were identified and 4 were included in the final analysis. The studies involved 1896 women, of whom 7 (0.37%) were affected by a further seizure. The weighted pooled prevalence of seizure recurrence was 0.18% (95% CI, 0.03-1.02). CONCLUSION: The absolute rate of long-term seizure recurrence after eclampsia is extremely low and within safe limits for driving.

The pathology and aetiology of subcortical clefts in infants.

In infants, traumatic surface contusions of the brain are rare but subcortical clefts or cysts, variously labelled "contusional tears", "contusional clefts", "cortical tears" or "parenchymal lacerations" have been ascribed to trauma, and are even said to be characteristic of shaking and abuse. We describe the pathology of subcortical clefts or haemorrhages in seven infants. In none were the axonal swellings characteristic of traumatic axonal injury seen in relation to the clefts. Subpial bleeding was associated with clefts in all the cases of recent onset. We hypothesize that subcortical clefts are not due to direct mechanical forces of trauma but are part of a secondary cascade caused by impaired venous drainage which may or may not follow trauma. The finding of subcortical and subpial haemorrhages should prompt a search for CVT. We consider the term "contusion" is not accurate and is misleading.

Current margin practice and effect on re-excision rates following the publication of the SSO-ASTRO consensus and ABS consensus guidelines: a national prospective study of 2858 women undergoing breast-conserving therapy in the UK and Ireland.

INTRODUCTION: There is variation in margin policy for breast conserving therapy (BCT) in the UK and Ireland. In response to the Society of Surgical Oncology and American Society for Radiation Oncology (SSO-ASTRO) margin consensus ('no ink on tumour' for invasive and 2 mm for ductal carcinoma in situ [DCIS]) and the Association of Breast Surgery (ABS) consensus (1 mm for invasive and DCIS), we report on current margin practice and unit infrastructure in the UK and Ireland and describe how these factors impact on re-excision rates. METHODS: A trainee collaborative-led multicentre prospective study was conducted in the UK and Ireland between 1st February and 31st May 2016. Data were collected on consecutive BCT patients and on local infrastructure and policies. RESULTS: A total of 79 sites participated in the data collection (75% screening units; average 372 cancers annually, range 70-900). For DCIS, 53.2% of units accept 1 mm and 38% accept 2-mm margins. For invasive disease 77.2% accept 1 mm and 13.9% accept 'no ink on tumour'. A total of 2858 patients underwent BCT with a mean re-excision rate of 17.2% across units (range 0-41%). The re-excision rate would be reduced to 15% if all units applied SSO-ASTRO guidelines and to 14.8% if all units followed ABS guidelines. Of those who required re-operation, 65% had disease present at margin. CONCLUSION: There continues to be large variation in margin policy and re-excision rates across units. Altering margin policies to follow either SSO-ASTRO or ABS guidelines would result in a modest reduction in the national re-excision rate. Most re-excisions are for involved margins rather than close margins.

Superconducting exchange coupling between ferromagnets.

Recent discoveries from superconductor (S)/ferromagnet (FM) heterostructures include π-junctions, triplet pairing, critical temperature (Tc) control in FM/S/FM superconducting spin valves (SSVs) and critical current control in S/FM/N/FM/S spin valve Josephson junctions (N: normal metal). In all cases, the magnetic state of the device, generally set by the applied field, controls the superconducting response. We report here the observation of the converse effect, that is, direct superconducting control of the magnetic state in GdN/Nb/GdN SSVs. A model for an antiferromagnetic effective exchange interaction based on the coupling of the superconducting condensation energy to the magnetic state can explain the Nb thickness and temperature dependence of this effect. This superconducting exchange interaction is fundamentally different in origin from the various exchange coupling phenomena that underlie conventional spin electronics (spintronics), and provides a mechanism for the active control of the magnetic state in superconducting spintronics.

In Situ Observations of Phase Transitions in Metastable Nickel (Carbide)/Carbon Nanocomposites.

Nanocomposite thin films comprised of metastable metal carbides in a carbon matrix have a wide variety of applications ranging from hard coatings to magnetics and energy storage and conversion. While their deposition using nonequilibrium techniques is established, the understanding of the dynamic evolution of such metastable nanocomposites under thermal equilibrium conditions at elevated temperatures during processing and during device operation remains limited. Here, we investigate sputter-deposited nanocomposites of metastable nickel carbide (Ni3C) nanocrystals in an amorphous carbon (a-C) matrix during thermal postdeposition processing via complementary in situ X-ray diffractometry, in situ Raman spectroscopy, and in situ X-ray photoelectron spectroscopy. At low annealing temperatures (300 °C) we observe isothermal Ni3C decomposition into face-centered-cubic Ni and amorphous carbon, however, without changes to the initial finely structured nanocomposite morphology. Only for higher temperatures (400-800 °C) Ni-catalyzed isothermal graphitization of the amorphous carbon matrix sets in, which we link to bulk-diffusion-mediated phase separation of the nanocomposite into coarser Ni and graphite grains. Upon natural cooling, only minimal precipitation of additional carbon from the Ni is observed, showing that even for highly carbon saturated systems precipitation upon cooling can be kinetically quenched. Our findings demonstrate that phase transformations of the filler and morphology modifications of the nanocomposite can be decoupled, which is advantageous from a manufacturing perspective. Our in situ study also identifies the high carbon content of the Ni filler crystallites at all stages of processing as the key hallmark feature of such metal-carbon nanocomposites that governs their entire thermal evolution. In a wider context, we also discuss our findings with regard to the much debated potential role of metastable Ni3C as a catalyst phase in graphene and carbon nanotube growth.

Nano-optical single-photon response mapping of waveguide integrated molybdenum silicide (MoSi) superconducting nanowires.

We present low temperature nano-optical characterization of a silicon-on-insulator (SOI) waveguide integrated SNSPD. The SNSPD is fabricated from an amorphous Mo83Si17 thin film chosen to give excellent substrate conformity. At 350 mK, the SNSPD exhibits a uniform photoresponse under perpendicular illumination, corresponding to a maximum system detection efficiency of approximately 5% at 1550 nm wavelength. Under these conditions 10 Hz dark count rate and 51 ps full width at half maximum (FWHM) timing jitter is observed.

Cerebral venous sinus thrombosis complicating traumatic head injury.

Cerebral venous sinus thrombosis (CVST) is a rare complication of traumatic head injury. Here we present a patient with traumatic extradural haematoma successfully evacuated with good clinical recovery. However, the patient then deteriorated and died. The cause, at post mortem, was a propagating CVST, sustained at the time of head injury. CVST, although rare, is therefore an important cause of deterioration in traumatic head injury. This patient with CVST is unique in that CVST was not considered as a diagnosis in the face of more obvious pathology and was responsible for late deterioration. We discuss the potential difficulties in both the detection and management of such a complication, particularly in association with extradural haematoma.

Vertically oriented TiO(x)N(y) nanopillar arrays with embedded Ag nanoparticles for visible-light photocatalysis.

We present a straightforward method to produce highly crystalline, vertically oriented TiO(x)N(y) nanopillars (up to 1 µm in length) with a band gap in the visible-light region. This process starts with reactive dc sputtering to produce a TiN porous film, followed by a simple oxidation process at elevated temperatures in oxygen or air. By controlling the oxidation conditions, the band gap of the prepared TiO(x)N(y) can be tuned to different wavelength within the range of visible light. Furthermore, in order to inhibit carrier recombination to enhance the photocatalytic activity, Ag nanoparticles have been embedded into the nanogaps between the TiO(x)N(y) pillars by photoinduced reduction of Ag(+) (aq) irradiated with visible light. Transmission electron microscopy reveals that the Ag nanoparticles with a diameter of about 10 nm are uniformly dispersed along the pillars. The prepared TiO(x)N(y) nanopillar matrix and Ag:TiO(x)N(y) network show strong photocatalytic activity under visible-light irradiation, evaluated via degradation of Rhodamine B.

Spin-filter Josephson junctions.

Josephson junctions with ferromagnetic barriers have been intensively investigated in recent years. Of particular interest has been the realization of so called π-junctions with a built-in phase difference, and induced triplet pairing. Such experiments have so far been limited to systems containing metallic ferromagnets. Although junctions incorporating a ferromagnetic insulator (I(F)) have been predicted to show a range of unique properties including π-shifts with intrinsically low dissipation and an unconventional temperature dependence of the critical current I(c), difficulties with the few known I(F) materials have prevented experimental tests. Here we report supercurrents through magnetic GdN barriers and show that the field and temperature dependence of I(c)is strongly modified by the I(F). In particular we show that the strong suppression of Cooper pair tunnelling by the spin filtering of the I(F) barrier can be modified by magnetic inhomogeneity in the barrier.

Preoperative assessment clinic: a missed learning opportunity?

BACKGROUND: Day-case surgery, theatre direct admissions and elective surgery have revolutionised the surgical patient's pathway, and have minimised the length of their hospital stay. However, with large numbers of medical students placed mostly at teaching hospitals, this has also significantly reduced students' exposure to clinical signs in surgery. This study aimed to assess whether the preoperative assessment clinic would be an appropriate teaching arena to offer medical students exposure to clinical signs. METHODS: Junior doctors assigned to the preoperative assessment clinic were asked to fill out a specially designed questionnaire for each patient they reviewed. This included the planned operation, presenting complaint, and identification and categorisation of objective clinical signs on examination. The assessor was asked whether the patient was suitable for, and amenable to, having medical students observe. The presenting complaints and clinical signs were referenced to the curriculum for Oxford University's second Bachelor of Medicine examinations (finals). RESULTS: Of the 100 patients seen in 40 clinics, only four refused to be seen by a medical student. Of the remaining patients, 89 (92%) had presenting complaints listed on the core curriculum for Oxford University. Seventy-six (79%) patients had objective clinical signs on examination. Only three patients (3%) had neither clinical signs nor core relevant presenting complaints. CONCLUSIONS: The results clearly demonstrate that preoperative assessment is an arena that would give medical students two important opportunities: to examine objective clinical signs and to take histories of presenting complaints from the core curriculum. This learning opportunity would otherwise be missed.