ABSTRACT
By making use of current-algebra Ward identities we study renormalization of general anisotropic current-current interactions in 2D. In this prescription we propose a compact expression for the beta function to all orders.
ABSTRACT
We consider the effects of disorder in a Dirac-like Hamiltonian. In order to use conformal field theory techniques, we argue that one should consider disorder in an imaginary vector potential. This affects significantly the signs of the lowest order beta functions. We present evidence for the existence of two distinct universality classes, depending on the relative strengths of the gauge field verses impurity disorder strengths. In one class all disorder is made irrelevant by the gauge field disorder.
ABSTRACT
Percutaneous injection of methylmethacrylate is now increasingly employed to treat bone lesions, both malignant and benign. However, the risks of this procedure are still to be fully established. In this report, we describe a case of rapid chondrolysis appearing after the intra-articular leakage of cement during injection of an acetabular subchondral cyst, resulting in hip replacement. Although the mechanism of such chondrolysis is unknown, this event suggests a chondrolytic effect of the acrylic cement. Thus, it is essential to systematically search for the presence of an intra-articular passage before injecting bone cement into a peri-articular cyst. This unusual complication highlights the need for rigorous evaluation of the benefits and risks of percutaneous injection of acrylic cement in the treatment of benign lesions, especially close to an articulation.
Subject(s)
Acetabulum/drug effects , Bone Cements/adverse effects , Bone Cysts/therapy , Cartilage Diseases/chemically induced , Cartilage, Articular/drug effects , Polymethyl Methacrylate/adverse effects , Acetabulum/surgery , Arthroplasty, Replacement, Hip , Cartilage Diseases/surgery , Cartilage, Articular/surgery , Femur Head/drug effects , Follow-Up Studies , Humans , Injections, Intra-Articular , Male , Middle Aged , Polymethyl Methacrylate/administration & dosage , Risk Factors , Tomography, X-Ray ComputedABSTRACT
A sustained-release, briquet formulation of methoprene (Altosid XR), applied at a rate of one briquet per catch basin in Saginaw, Michigan, provided ca. 70% reduction in emergence of Culex pipiens and Cx. restuans adults, compared with nontreated catch basins, during a period of 15 wk in the summer of 1990. In a parallel study using one briquet per 10.5 liter bucket, there was 99% reduction in adult emergence of these species for a period of 12 weeks. The difference between catch basins and buckets may be attributable to water movement through the catch basins with each rainfall, causing a dilution of methoprene through time. However, both studies indicated that the briquets released methoprene for 12-15 wk, suggesting that this formulation may offer season-long control of Culex mosquitoes from urban catch basins in Michigan, with a single treatment of insecticide.
Subject(s)
Culex , Methoprene , Mosquito Control/methods , Animals , Delayed-Action Preparations , Ecology , Michigan , Urban PopulationABSTRACT
This revision rod, used temporarily, is interlocked in the distal healthy part of the femur. It is indicated in the treatment of loosening, even with extensive destruction, whether this is done by filling the fragile part of the femur with bone chips and marrow or by reconstruction accomplished by gliding the femoral heads on the rod. The clinical results were observed for 21 replacements, performed between 1987 and 1990, for the following indications: 14 loosenings, of which 10 had major bone defects; 4 fractures, of which 3 received a prosthesis; 2 infected resection prostheses; and one broken porous metal Judet prosthesis. There was one failure due to flare-up of infection in a prosthesis that was initially infected. The complete treatment, with implantation of a standard prosthesis, was only performed in 5 cases. We left the revision rod in place in elderly patients, in major reconstructions, or when the patients refused a new operation. The anatomical results are encouraging. There was good assimilation of the bone grafts, confirmed by histology in cases of revision. There was no rupture or displacement of the material. The functional results were good with respect to pain and range of motion; they were less good with respect to stability, as could be expected in repeatedly operated patients.
