Evidence for the coexistence of Dirac and massive carriers in a-(BEDT-TTF)2I3 under hydrostatic pressure

Transport measurements were performed on the organic layered compound \aI3 under hydrostatic pressure. The carrier types, densities and mobilities are determined from the magneto-conductance of \aI3 . While evidence of high-mobility massless Dirac carriers has already been given, we report here, their coexistence with low-mobility massive holes. This coexistence seems robust as it has been found up to the highest studied pressure. Our results are in agreement with recent DFT calculations of the band structure of this system under hydrostatic pressure. A comparison with graphene Dirac carriers has also been done.Comment: 5 pages 5 figure

Autoresuscitation (Lazarus phenomenon) after termination of cardiopulmonary resuscitation - a scoping review.

Autoresuscitation describes the return of spontaneous circulation after termination of resuscitation (TOR) following cardiac arrest (CA). We aimed to identify phenomena that may lead to autoresuscitation and to provide guidance to reduce the likelihood of it occurring. We conducted a literature search (Google Scholar, MEDLINE, PubMed) and a scoping review according to PRISMA-ScR guidelines of autoresuscitation cases where patients undergoing CPR recovered circulation spontaneously after TOR with the following criteria: 1) CA from any cause; 2) CPR for any length of time; 3) A point was reached when it was felt that the patient had died; 4) Staff declared the patient dead and stood back. No further interventions took place; 5) Later, vital signs were observed. 6) Vital signs were sustained for more than a few seconds, such that staff had to resume active care. Sixty-five patients with ROSC after TOR were identified in 53 articles (1982-2018), 18 (28%) made a full recovery. Almost a third made a full recovery after autoresuscitation. The following reasons for and recommendations to avoid autoresuscitation can be proposed: 1) In asystole with no reversible causes, resuscitation efforts should be continued for at least 20 min; 2) CPR should not be abandoned immediately after unsuccessful defibrillation, as transient asystole can occur after defibrillation; 3) Excessive ventilation during CPR may cause hyperinflation and should be avoided; 4) In refractory CA, resuscitation should not be terminated in the presence of any potentially-treatable cardiac rhythm; 5) After TOR, the casualty should be observed continuously and ECG monitored for at least 10 min

Opening wedge high tibial osteotomy performed without filling the defect but with locking plate fixation (TomoFix™) and early weight-bearing: Prospective evaluation of bone union, precision and maintenance of correction in 51 cases

SummaryIntroductionA medial opening wedge high tibial osteotomy (HTO), where the osteotomy site is filled, is often preferred to a lateral closing osteotomy, but filling the defect can lead to certain complications.HypothesisA medial opening HTO can be performed without filling the bone defect if fixation is carried out with a specially-designed stiff locking plate.Patients and methodsFifty-one patients, 37 to 72 years of age where followed prospectively and continuously from 2003 to 2006. A single surgical technique was used: medial opening HTO with locked plate fixation (TomoFix™, Synthes) but without filling the defect. The preoperative genu varum could not exceed 15°. The following were evaluated: time to return to weight-bearing, IKS functional score, long-leg standing film performed preoperative, postoperative and at follow-up to evaluate limb alignment and validate the precision of the correction and its stability over time. A measurement of the area of bone union in the osteotomy site was used to quantify the rate of union.ResultsBone union occurred at 4.5 months on average; two cases of incomplete union (7%) were found and revised with an autograft at 7 and 9 months. Lower-limb alignment was 7.5° of varus on average before surgery (3° to 15° varus, SD=2.85) and 1.2° of valgus on average after the surgery (4° varus to 5° valgus, SD=1.78). The correction was maintained at 1 year post-surgery. The average IKS knee score went from 69±15.5 (range 25 to 96) before surgery to 90±7.4 (range 66 to 98) at follow-up (P=0.0001). Full weight-bearing without assistance was possible after 3 months on average (range 1.5 to 8, SD=1.21). Forty-seven patients (92%) were fully weight-bearing after 2 months. Forty-eight patients were able to return to work and sporting activities at the same or a higher level than before the procedure.DiscussionBone union seems to happen more slowly when the defect is filled; however, there are doubts about radiological evaluation of bone union in different published studies. When osteotomy defect was left unfilled in this study, union and filling of 4/5 of the osteotomy site was obtained in 4.2 months for 49 of the 51 cases. Fixation with the locking plate is reliable and provides stable correction and the option for early weight-bearing.Level of proofLevel IV, prospective cohort study

Boundary conformal field theories and loop models

We propose a systematic method to extract conformal loop models for rational conformal field theories (CFT). Method is based on defining an ADE model for boundary primary operators by using the fusion matrices of these operators as adjacency matrices. These loop models respect the conformal boundary conditions. We discuss the loop models that can be extracted by this method for minimal CFTs and then we will give dilute O(n) loop models on the square lattice as examples for these loop models. We give also some proposals for WZW SU(2) models.Comment: 23 Pages, major changes! title change

Loop models and their critical points

Loop models have been widely studied in physics and mathematics, in problems ranging from polymers to topological quantum computation to Schramm-Loewner evolution. I present new loop models which have critical points described by conformal field theories. Examples include both fully-packed and dilute loop models with critical points described by the superconformal minimal models and the SU(2)_2 WZW models. The dilute loop models are generalized to include SU(2)_k models as well.Comment: 20 pages, 15 figure

The Blob Algebra and the Periodic Temperley-Lieb Algebra

We determine the structure of two variations on the Temperley-Lieb algebra, both used for dealing with special kinds of boundary conditions in statistical mechanics models. The first is a new algebra, the `blob' algebra (the reason for the name will become obvious shortly!). We determine both the generic and all the exceptional structures for this two parameter algebra. The second is the periodic Temperley-Lieb algebra. The generic structure and part of the exceptional structure of this algebra have already been studied. Here we complete the analysis, using results from the study of the blob algebra.Comment: 12 page

The half-filled Landau level - composite fermions and dipoles

The composite-fermion approach as formulated in the fermion Chern-Simons theory has been very successful in describing the physics of the lowest Landau level near Landau level filling factor 1/2. Recent work has emphasized the fact that the true quasiparticles at these filling factors are electrically neutral and carry an electric dipole moment. In a previous work, we discussed at length two formulations in terms of dipolar quasiparticles. Here we briefly review one approach - termed electron-centered quasiparticles - and show how it can be extended from 1/2 to nearby filling factors where the quasiparticles carry both an electric dipole moment and an overall charge.Comment: 10 pages, minor improvements of notation and referencin

Technique to treat iliopsoas irritation after total hip replacement: Thickening of articular hip capsule through an abridged direct anterior approach

AbstractIliopsoas irritation due to acetabular cup component impingement following total hip arthroplasty (THA) is usually treated by infiltration or by distal iliopsoas tenotomy in case of recurrence; however, this can result in an active flexion deficit of the thigh. To prevent this complication, we developed an original technique that we performed between 2012 and 2014 in patients with recurrent impingement following extraarticular corticosteroid injections. This included 5 patients (mean age: 64 [53–75] years old) in whom we performed an ambulatory bursectomy by the Hueter approach and placed a polyglactin 910 (Vicryl™) mesh plate on the entire anterior hip capsule. After a mean follow-up of 12months (9–29months), anterior pain had decreased in all patients with improvement and an increase in the Oxford-12 (mean: 15 points [10–19]), Merle d’Aubigné (mean: 2.5 points [1–5]) and Harris (mean: 18 points [10–29]) scores. No flexion deficits were observed. An infected postoperative hematoma had to be drained but was cured at follow-up. This simple procedure provides satisfactory results and preserves THA function. It does not jeopardize future procedures and is an alternative option in case of unsuccessful conservative treatment

Gravity of a static massless scalar field and a limiting Schwarzschild-like geometry

We study a set of static solutions of the Einstein equations in presence of a massless scalar field and establish their connection to the Kantowski-Sachs cosmological solutions based on some kind of duality transformations. The physical properties of the limiting case of an empty hyperbolic spacetime (pseudo-Schwarzschild geometry) are analyzed in some detail.Comment: 13 pages, 4 figure

Interacting classical dimers on the square lattice

We study a model of close-packed dimers on the square lattice with a nearest neighbor interaction between parallel dimers. This model corresponds to the classical limit of quantum dimer models [D.S. Rokhsar and S.A. Kivelson, Phys. Rev. Lett.{\bf 61}, 2376 (1988)]. By means of Monte Carlo and Transfer Matrix calculations, we show that this system undergoes a Kosterlitz-Thouless transition separating a low temperature ordered phase where dimers are aligned in columns from a high temperature critical phase with continuously varying exponents. This is understood by constructing the corresponding Coulomb gas, whose coupling constant is computed numerically. We also discuss doped models and implications on the finite-temperature phase diagram of quantum dimer models.Comment: 4 pages, 4 figures; v2 : Added results on doped models; published versio