Classification of Shredded Aluminium Scrap Metal Using Magnetic Induction Spectroscopy.

Recycling aluminium is essential for a circular economy, reducing the energy required and greenhouse gas emissions compared to extraction from virgin ore. A 'Twitch' waste stream is a mix of shredded wrought and cast aluminium. Wrought must be separated before recycling to prevent contamination from the impurities present in the cast. In this paper, we demonstrate magnetic induction spectroscopy (MIS) to classify wrought from cast aluminium. MIS measures the scattering of an oscillating magnetic field to characterise a material. The conductivity difference between cast and wrought makes it a promising choice for MIS. We first show how wrought can be classified on a laboratory system with 89.66% recovery and 94.96% purity. We then implement the first industrial MIS material recovery solution for sorting Twitch, combining our sensors with a commercial-scale separator system. The industrial system did not reflect the laboratory results. The analysis found three areas of reduced performance: (1) metal pieces correctly classified by one sensor were misclassified by adjacent sensors that only captured part of the metal; (2) the metal surface facing the sensor can produce different classification results; and (3) the choice of machine learning algorithm is significant with artificial neural networks producing the best results on unseen data.

Quantized Nonlinear Conductance in Ballistic Metals.

We introduce a nonlinear frequency-dependent D+1 terminal conductance that characterizes a D-dimensional Fermi gas, generalizing the Landauer conductance in D=1. For a 2D ballistic conductor, we show that this conductance is quantized and probes the Euler characteristic of the Fermi sea. We critically address the roles of electrical contacts and Fermi liquid interactions, and we propose experiments on 2D Dirac materials, such as graphene, using a triple point contact geometry.

Fibonacci Topological Superconductor.

We introduce a model of interacting Majorana fermions that describes a superconducting phase with a topological order characterized by the Fibonacci topological field theory. Our theory, which is based on a SO(7)_{1}/(G_{2})_{1} coset factorization, leads to a solvable one-dimensional model that is extended to two dimensions using a network construction. In addition to providing a description of the Fibonacci phase without parafermions, our theory predicts a closely related "anti-Fibonacci" phase, whose topological order is characterized by the tricritical Ising model. We show that Majorana fermions can split into a pair of Fibonacci anyons, and propose an interferometer that generalizes the Z_{2} Majorana interferometer and directly probes the Fibonacci non-Abelian statistics.

Fractional Excitonic Insulator.

We argue that a correlated fluid of electrons and holes can exhibit a fractional quantum Hall effect at zero magnetic field analogous to the Laughlin state at filling 1/m. We introduce a variant of the Laughlin wave function for electrons and holes and show that for m=1 it is the exact ground state of a free fermion model that describes p_{x}+ip_{y} excitonic pairing. For m>1 we develop a simple composite fermion mean field theory, and we present evidence that our wave function correctly describes this phase. We derive an interacting Hamiltonian for which our wave function is the exact ground state, and we present physical arguments that the m=3 state can be realized in a system in which energy bands with angular momentum that differ by 3 cross at the Fermi energy. This leads to a gapless state with (p_{x}+ip_{y})^{3} excitonic pairing, which we argue is conducive to forming the fractional excitonic insulator in the presence of interactions. Prospects for numerics on model systems and band structure engineering to realize this phase in real materials are discussed.

Dirac-Weyl Semimetal: Coexistence of Dirac and Weyl Fermions in Polar Hexagonal ABC Crystals.

We propose that the noncentrosymmetric LiGaGe-type hexagonal ABC crystal SrHgPb realizes a new type of topological semimetal that hosts both Dirac and Weyl points in momentum space. The symmetry-protected Dirac points arise due to a band inversion and are located on the sixfold rotation z axis, whereas the six pairs of Weyl points related by sixfold symmetry are located on the perpendicular k_{z}=0 plane. By studying the electronic structure as a function of the buckling of the HgPb layer, which is the origin of inversion symmetry breaking, we establish that the coexistence of Dirac and Weyl fermions defines a phase separating two topologically distinct Dirac semimetals. These two Dirac semimetals are distinguished by the Z_{2} index of the k_{z}=0 plane and the corresponding presence or absence of 2D Dirac fermions on side surfaces. We formalize our first-principles calculations by deriving and studying a low-energy model Hamiltonian describing the Dirac-Weyl semimetal phase. We conclude by proposing several other materials in the noncentrosymmetric ABC material class, in particular SrHgSn and CaHgSn, as candidates for realizing the Dirac-Weyl semimetal.

Aspirin reduces lipopolysaccharide-induced pulmonary inflammation in human models of ARDS.

RATIONALE: Platelets play an active role in the pathogenesis of acute respiratory distress syndrome (ARDS). Animal and observational studies have shown aspirin's antiplatelet and immunomodulatory effects may be beneficial in ARDS. OBJECTIVE: To test the hypothesis that aspirin reduces inflammation in clinically relevant human models that recapitulate pathophysiological mechanisms implicated in the development of ARDS. METHODS: Healthy volunteers were randomised to receive placebo or aspirin 75  or 1200 mg (1:1:1) for seven days prior to lipopolysaccharide (LPS) inhalation, in a double-blind, placebo-controlled, allocation-concealed study. Bronchoalveolar lavage (BAL) was performed 6 hours after inhaling 50 µg of LPS. The primary outcome measure was BAL IL-8. Secondary outcome measures included markers of alveolar inflammation (BAL neutrophils, cytokines, neutrophil proteases), alveolar epithelial cell injury, systemic inflammation (neutrophils and plasma C-reactive protein (CRP)) and platelet activation (thromboxane B2, TXB2). Human lungs, perfused and ventilated ex vivo (EVLP) were randomised to placebo or 24 mg aspirin and injured with LPS. BAL was carried out 4 hours later. Inflammation was assessed by BAL differential cell counts and histological changes. RESULTS: In the healthy volunteer (n=33) model, data for the aspirin groups were combined. Aspirin did not reduce BAL IL-8. However, aspirin reduced pulmonary neutrophilia and tissue damaging neutrophil proteases (Matrix Metalloproteinase (MMP)-8/-9), reduced BAL concentrations of tumour necrosis factor α and reduced systemic and pulmonary TXB2. There was no difference between high-dose and low-dose aspirin. In the EVLP model, aspirin reduced BAL neutrophilia and alveolar injury as measured by histological damage. CONCLUSIONS: These are the first prospective human data indicating that aspirin inhibits pulmonary neutrophilic inflammation, at both low and high doses. Further clinical studies are indicated to assess the role of aspirin in the prevention and treatment of ARDS. TRIAL REGISTRATION NUMBER: NCT01659307 Results.

Usefulness of Dried Blood Spots (DBS) to perform hepatitis C virus genotyping in drug users in Senegal.

The aim of this pilot study was to analyze the Hepatitis C Virus (HCV) genotypes circulating in Senegal among Drug User (DUs), using Dried Blood Spots (DBS) as RNA source for molecular assays. Heroin and/or cocaine users (n = 506) were recruited in Dakar from April to July 2011, using a Respondent Driven Sampling (RDS) method. DBS preparation consisted of five drops of whole blood from finger applied to a Whatman paper card. HCV infection was screened by the detection of anti-HCV antibodies, using a rapid immune-chromatographic test. HCV RNA was quantified on anti-HCV positive DBS, using the Abbott RealTime HCV® Genotyping was performed on DBS with detectable viral load with Versant® HCV Genotype 2.0 Assay (LiPA) and Abbott RealTime HCV Genotype II assay®. Among the 506 participants, 120 were tested as positive for anti-HCV antibodies and their samples were analyzed for HCV RNA viral load and genotype. Out of the 120 DBS tested, HCV RNA was detected on 25 (20.8%). The median viral load was 15,058 IU/ml (ranging from 710 to 766,740 IU/ml). All positive DBS were suitable for the genotyping assay, that showed a predominance of genotype 1 (21/25) including 16 genotypes 1a and 5 genotypes 1b. HCV genotype 1 prevails in a DU population in Dakar. DBS could be useful for HCV RNA genotyping, but optimal storage conditions should required avoiding RNA impairment. Acknowledging this limitation, DBS could be a great interest for detecting and genotyping HCV viremic patients. J. Med. Virol. 89:484-488, 2017. © 2015 Wiley Periodicals, Inc.

Simvastatin for patients with acute respiratory distress syndrome: long-term outcomes and cost-effectiveness from a randomised controlled trial.

BACKGROUND: Simvastatin therapy for patients with acute respiratory distress syndrome (ARDS) has been shown to be safe and associated with minimal adverse effects, but it does not improve clinical outcomes. The aim of this research was to report on mortality and cost-effectiveness of simvastatin in patients with ARDS at 12 months. METHODS: This was a cost-utility analysis alongside a multicentre, double-blind, randomised controlled trial carried out in the UK and Ireland. Five hundred and forty intubated and mechanically ventilated patients with ARDS were randomly assigned (1:1) to receive once-daily simvastatin (at a dose of 80 mg) or identical placebo tablets enterally for up to 28 days. RESULTS: Mortality was lower in the simvastatin group (31.8%, 95% confidence interval (CI) 26.1-37.5) compared to the placebo group (37.3%, 95% CI 31.6-43.0) at 12 months, although this was not significant. Simvastatin was associated with statistically significant quality-adjusted life year (QALY) gain (incremental QALYs 0.064, 95% CI 0.002-0.127) compared to placebo. Simvastatin was also less costly (incremental total costs -£3601, 95% CI -8061 to 859). At a willingness-to-pay threshold of £20,000 per QALY, the probability of simvastatin being cost-effective was 99%. Sensitivity analyses indicated that the results were robust to changes in methodological assumptions with the probability of cost-effectiveness never dropping below 90%. CONCLUSION: Simvastatin was found to be cost-effective for the treatment of ARDS, being associated with both a significant QALY gain and a cost saving. There was no significant reduction in mortality at 12 months, TRIAL REGISTRATION: ISRCTN, 88244364. Registered 26 November 2010.

Safety of sedation for gastrointestinal endoscopy in a group of university-affiliated hospitals: a prospective cohort study.

BACKGROUND: Service models for gastrointestinal endoscopy sedation must be safe, as endoscopy is the most common procedure performed under sedation in many countries. The aim of this prospective cohort study was to determine the patient risk profile, and incidence of and risk factors for significant unplanned events, in adult patients presenting for gastrointestinal endoscopy in a group of university-affiliated hospitals where most sedation is managed by anaesthetists. METHODS: Patients aged ≥18 yr presenting for elective and emergency gastrointestinal endoscopy under anaesthetist-managed sedation at nine hospitals affiliated with the University of Melbourne, Australia, were included. Outcomes included significant airway obstruction, hypoxia, hypotension and bradycardia; unplanned tracheal intubation; abandoned procedure; advanced life support; prolonged post-procedure stay; unplanned over-night admission and 30-day mortality. RESULTS: 2,132 patients were included. Fifty percent of patients were aged >60 yr, 50% had a BMI >27 kg m -2, 42% were ASA physical status III-V and 17% were emergency patients. The incidence of significant unplanned events was 23.0% (including significant hypotension 11.8%). Significant unplanned intraoperative events were associated with increasing age, BMI <18.5 kg m -2, ASA physical status III-V, colonoscopy and planned tracheal intubation. Thirty-day mortality was 1.2% (0.2% in electives and 6.0% in emergencies) and was associated with ASA physical status IV-V and emergency status. CONCLUSIONS: Patients presenting for gastrointestinal endoscopy at a group of public university-affiliated hospitals where most sedation is managed by anaesthetists, had a high risk profile and a substantial incidence of significant unplanned intraoperative events and 30-day mortality.

Implementation of an in-house quantitative real-time polymerase chain reaction method for Hepatitis B virus quantification in West African countries.

Hepatitis B virus (HBV) is a major cause of chronic liver disease worldwide. HBV infection is diagnosed by serological tests, while real-time polymerase chain reaction (qRT-PCR) assays are used to quantify viral load, which is a crucial parameter to determine viral replication and to monitor antiviral treatments. However, measuring viral load in resource-limited countries remains nonsystematic, due to the high cost of commercial kits. Here, we describe the development, validation and implementation of a low-cost, in-house qRT-PCR assay to monitor HBV viral load in chronic carriers enrolled in the PROLIFICA programme in the Gambia and Senegal. Over 1500 HBsAg-positive patients, including 210 chronically infected HBV patients, who were given antiviral treatment (tenofovir), were monitored by qRT-PCR using the SYBR Green- and HBV-specific primers. Twenty-four tenofovir-treated patients were followed up and their viral load was tested every 3 months over the 12-month experimental time course. Compared to commercial assays, our in-house assay was shown to be (i) highly reliable, with good intra- and interassay reproducibility over a wide range (45-4.5 × 108 copies mL-1 ), (ii) very similar in the viral loads detected (R2  = .90), (iii) highly sensitive, as it detected loads as low as 30 copies mL-1 (~5 IU mL-1 ), (iv) cheaper (2- to 3-fold), (v) easier to implement and (vi) more rapid. Based on our experience, we recommend this assay as a reliable alternative to commercial assays, for monitoring HBV viraemia in resource-limited, highly endemic countries to reduce the cost and technical obstacles associated with commercial kits.

Topological Phonons and Weyl Lines in Three Dimensions.

Topological mechanics and phononics have recently emerged as an exciting field of study. Here we introduce and study generalizations of the three-dimensional pyrochlore lattice that have topologically protected edge states and Weyl lines in their bulk phonon spectra, which lead to zero surface modes that flip from one edge to the opposite as a function of surface wave number.

Double Dirac Semimetals in Three Dimensions.

We study a class of Dirac semimetals that feature an eightfold-degenerate double Dirac point. We show that 7 of the 230 space groups can host such Dirac points and argue that they all generically display linear dispersion. We introduce an explicit tight-binding model for space groups 130 and 135. Space group 135 can host an intrinsic double Dirac semimetal with no additional states at the Fermi energy. This defines a symmetry-protected topological critical point, and we show that a uniaxial compressive strain applied in different directions leads to topologically distinct insulating phases. In addition, the double Dirac semimetal can accommodate topological line defects that bind helical modes. Connections are made to theories of strongly interacting filling-enforced semimetals, and potential materials realizations are discussed.

Observation of neutral modes in the fractional quantum Hall regime.

The quantum Hall effect takes place in a two-dimensional electron gas under a strong magnetic field and involves current flow along the edges of the sample. For some particle-hole conjugate states of the fractional regime (for example, with fillings between 1/2 and 1 of the lowest Landau level), early predictions suggested the presence of counter-propagating edge currents in addition to the expected ones. When this did not agree with the measured conductance, it was suggested that disorder and interactions will lead to counter-propagating modes that carry only energy--the so called neutral modes. In addition, a neutral upstream mode (the Majorana mode) was expected for selected wavefunctions proposed for the even-denominator filling 5/2. Here we report the direct observation of counter-propagating neutral modes for fillings of 2/3, 3/5 and 5/2. The basis of our approach is that, if such modes impinge on a narrow constriction, the neutral quasiparticles will be partly reflected and fragmented into charge carriers, which can be detected through shot noise measurements. We find that the resultant shot noise is proportional to the injected current. Moreover, when we simultaneously inject a charge mode, the presence of the neutral mode was found to significantly affect the Fano factor and the temperature of the backscattered charge mode. In particular, such observations for filling 5/2 may single out the non-Abelian wavefunctions for the state.

Phonons and elasticity in critically coordinated lattices.

Much of our understanding of vibrational excitations and elasticity is based upon analysis of frames consisting of sites connected by bonds occupied by central-force springs, the stability of which depends on the average number of neighbors per site z. When z < zc ≈ 2d, where d is the spatial dimension, frames are unstable with respect to internal deformations. This pedagogical review focuses on the properties of frames with z at or near zc, which model systems like randomly packed spheres near jamming and network glasses. Using an index theorem, N0 -NS = dN -NB relating the number of sites, N, and number of bonds, NB, to the number, N0, of modes of zero energy and the number, NS, of states of self stress, in which springs can be under positive or negative tension while forces on sites remain zero, it explores the properties of periodic square, kagome, and related lattices for which z = zc and the relation between states of self stress and zero modes in periodic lattices to the surface zero modes of finite free lattices (with free boundary conditions). It shows how modifications to the periodic kagome lattice can eliminate all but trivial translational zero modes and create topologically distinct classes, analogous to those of topological insulators, with protected zero modes at free boundaries and at interfaces between different topological classes.

Layered Topological Crystalline Insulators.

Topological crystalline insulators (TCIs) are insulating materials whose topological property relies on generic crystalline symmetries. Based on first-principles calculations, we study a three-dimensional (3D) crystal constructed by stacking two-dimensional TCI layers. Depending on the interlayer interaction, the layered crystal can realize diverse 3D topological phases characterized by two mirror Chern numbers (MCNs) (µ1,µ2) defined on inequivalent mirror-invariant planes in the Brillouin zone. As an example, we demonstrate that new TCI phases can be realized in layered materials such as a PbSe (001) monolayer/h-BN heterostructure and can be tuned by mechanical strain. Our results shed light on the role of the MCNs on inequivalent mirror-symmetric planes in reciprocal space and open new possibilities for finding new topological materials.

Dirac Line Nodes in Inversion-Symmetric Crystals.

We propose and characterize a new Z2 class of topological semimetals with a vanishing spin-orbit interaction. The proposed topological semimetals are characterized by the presence of bulk one-dimensional (1D) Dirac line nodes (DLNs) and two-dimensional (2D) nearly flat surface states, protected by inversion and time-reversal symmetries. We develop the Z2 invariants dictating the presence of DLNs based on parity eigenvalues at the parity-invariant points in reciprocal space. Moreover, using first-principles calculations, we predict DLNs to occur in Cu_{3}N near the Fermi energy by doping nonmagnetic transition metal atoms, such as Zn and Pd, with the 2D surface states emerging in the projected interior of the DLNs. This Letter includes a brief discussion of the effects of spin-orbit interactions and symmetry breaking as well as comments on experimental implications.

3D geometry analysis of the medial meniscus--a statistical shape modeling approach.

The geometry-dependent functioning of the meniscus indicates that detailed knowledge on 3D meniscus geometry and its inter-subject variation is essential to design well functioning anatomically shaped meniscus replacements. Therefore, the aim of this study was to quantify 3D meniscus geometry and to determine whether variation in medial meniscus geometry is size- or shape-driven. Also we performed a cluster analysis to identify distinct morphological groups of medial menisci and assessed whether meniscal geometry is gender-dependent. A statistical shape model was created, containing the meniscus geometries of 35 subjects (20 females, 15 males) that were obtained from MR images. A principal component analysis was performed to determine the most important modes of geometry variation and the characteristic changes per principal component were evaluated. Each meniscus from the original dataset was then reconstructed as a linear combination of principal components. This allowed the comparison of male and female menisci, and a cluster analysis to determine distinct morphological meniscus groups. Of the variation in medial meniscus geometry, 53.8% was found to be due to primarily size-related differences and 29.6% due to shape differences. Shape changes were most prominent in the cross-sectional plane, rather than in the transverse plane. Significant differences between male and female menisci were only found for principal component 1, which predominantly reflected size differences. The cluster analysis resulted in four clusters, yet these clusters represented two statistically different meniscal shapes, as differences between cluster 1, 2 and 4 were only present for principal component 1. This study illustrates that differences in meniscal geometry cannot be explained by scaling only, but that different meniscal shapes can be distinguished. Functional analysis, e.g. through finite element modeling, is required to assess whether these distinct shapes actually influence the biomechanical performance of the meniscus.

Time-reversal-invariant Z4 fractional Josephson effect.

We study the Josephson junction mediated by the quantum spin Hall edge states and show that electron-electron interactions lead to a dissipationless fractional Josephson effect in the presence of time-reversal symmetry. Surprisingly, the periodicity is 8π, corresponding to a Josephson frequency eV/2ℏ. We estimate the magnitude of interaction-induced many-body level splitting responsible for this effect and argue that it can be measured by using tunneling spectroscopy. For strong interactions we show that the Josephson effect is associated with the weak tunneling of charge e/2 quasiparticles between the superconductors. Our theory describes a fourfold ground state degeneracy that is similar to that of coupled "fractional" Majorana modes but is protected by time-reversal symmetry.

Bulk Dirac points in distorted spinels.

We report on a Dirac-like Fermi surface in three-dimensional bulk materials in a distorted spinel structure on the basis of density functional theory as well as tight-binding theory. The four examples we provide in this Letter are BiZnSiO4, BiCaSiO4, BiAlInO4, and BiMgSiO4. A necessary characteristic of these structures is that they contain a Bi lattice which forms a hierarchy of chainlike substructures, with consequences for both fundamental understanding and materials design.

A Multicentric, Retrospective, Real-world Study on Immune-related Adverse Events in Patients with Advanced Non-small Cell Lung Cancers Treated with Pembrolizumab Monotherapy.

AIMS: We present 7 years of clinical experience with single-agent pembrolizumab immune checkpoint inhibitor immunotherapy in non-small cell lung cancers (NSCLC) from four UK cancer centres. MATERIALS AND METHODS: This multi-institutional retrospective cohort study included 226 metastatic NSCLC patients. Outcomes were number and severity of immune-related adverse events (irAEs), median progression-free survival (mPFS) and median overall survival (mOS). RESULTS: Within our cohort, 119/226 (53%) patients developed irAEs. Of these, 54/119 (45%) experienced irAEs affecting two or more organ systems. The most common irAEs were diarrhoea and rash. The development of an irAE was associated with better mOS (20.7 versus 8.0 months; P < 0.001) and mPFS (12.0 versus 3.9 months; P < 0.001). The development of grade 3/4 toxicities was associated with worse outcomes compared with the development of grade 1/2 toxicities (mOS 6.1 months versus 25.2 months, P < 0.01; mPFS 5.6 months versus 19.3 months, P = 0.01, respectively). Females had a higher proportion of reported grade 3/4 toxicities (13/44 [29.5%] versus 10/74 [13.5%], P = 0.03). Using a multiple Cox regression model, the presence of irAEs was associated with a better overall survival (hazard ratio = 0.42, 95% confidence interval 0.29-0.61; P < 0.01) and better PFS (hazard ratio 0.38, 95% confidence interval 0.27-0.53; P < 0.001). CONCLUSION: In this multicentre retrospective cohort study, the development of at least one irAE was associated with significantly longer mPFS and mOS; however, more severe grade 3 and 4 irAEs were associated with worse outcomes. Delayed-onset irAEs, after the 3-month timepoint, were associated with better clinical outcomes.