2,506 research outputs found

    Epsilon-expansion in quantum field theory in curved spacetime

    Full text link
    We discuss epsilon-expansion in curved spacetime for asymptotically free and asymptotically non-free theories. The esistence of stable and unstable fixed points is investigated for fϕ4f \phi^4 and SU(2) gauge theory. It is shown that epsilon-expansion maybe compatible with asymptotic freedom on special solutions of the RG equations in a special case (supersymmetric theory). Using epsilon-expansion RG technique the effective Lagrangian for covariantly constant gauge SU(2) field and effective potential for gauged NJL-model are found in 4-epsilon- dimensional curved space (in linear curvature approximation). The curvature- induced phase transitions from symmetric phase to asymmetric phase (chromomagnetic vacuum and chiral symmetry broken phase, respectively) are discussed for the above two models.Comment: Latex file, 22 pages, July 1997 preprin

    Anti-VEGF therapy for retinal diseases treatment : recommendations for it practice in Colombia

    Get PDF
    Objetivo: Exponer la experiencia local sobre el tratamiento de las enfermedades retinales con terapias anti factor de crecimiento endotelial vascular (anti-VEGF) y crear conciencia en relación con la atención centrada en el paciente reconociendo el papel de los médicos especialistas en la determinación del tratamiento más apropiado basado principalmente en la evidencia científica, pero también teniendo en cuenta la experiencia y práctica exitosas en el manejo de cada paciente, con base en sus características únicas e individuales. Método: Revisión y comparación de la literatura científica con la experiencia de los autores, en el diagnóstico y tratamiento de las enfermedades que involucran inyecciones intraoculares, haciendo especial énfasis en la degeneración macular relacionada con la edad neo vascular (DMRE-NV), el edema macular diabético (EMD), la retinopatía diabética (RD), edema macular por oclusión venosa de rama de vena central de la retina (ORVR), la oclusión de vena central de la retina (OVCR) y la neo vascularización sub retiniana asociada a miopía patológica (MP). Resultados: la revisión realizada reafirma que tanto cuando hablamos de clases de medicamentos, de algoritmos de tratamiento o de perfiles de paciente, los diferentes agentes de una misma clase terapéutica pueden tener eficacias o perfiles de seguridad variables. Se debe considerar la importancia clínica que representa la valoración adecuada de los resultados pos tratamiento, pero sobre todo, la selección cuidadosa para determinar el agente y esquema más apropiado en la intención de tratar a un paciente. Si bien existen recomendaciones y guías de tratamiento para las patologías, los protocolos en el manejo individualizado y la exposición de estas experiencias de vida real se hacen necesarios, ya que no todos los pacientes ni todas las enfermedades de la retina responden de igual forma a cada agente terapéutico. Conclusión: La eficacia y seguridad en el uso de las terapias anti-VEGF son aspectos de suma importancia cuando se trata de proporcionar una atención verdaderamente centrada en el paciente. No hay ninguna solución, intervención o alternativa terapéutica que se ajuste a todas las enfermedades oculares complejas, por lo que es importante hacer un balance que considere la evidencia disponible, la experiencia, y las expectativas de los pacientes y tratantes. Esto permitirá acceder a las alternativas terapéuticas adecuadas, en el momento adecuado siempre teniendo en mente los perfiles de eficacia, seguridad, farmacovigilancia activa y los costos asociados a las alternativas terapéuticas utilizadas en el país.46-62Purpose: To display local experience on treatment for retinal diseases with anti-Vascular Endothelial Growth Factor (anti-VEGF) therapies and to raise awareness regarding patient-centered care, recognizing the role of medical specialists in determining the most appropriate treatment mainly based on scientific evidence, but also considering the successful experience and practice handling each patient, based on their unique and individual characteristics. Method: Review and comparison of scientific literature according to the authors experience to diagnose and treat diseases involving intraocular injections, focusing on Neovascular Age-related Macular Degeneration (NV-AMD), Diabetic Macular Edema (DME), Diabetic Retinopathy (DR), Macular Edema due to Branch Retinal Vein Occlusion (BRVO), Central Retinal Vein Occlusion (CRVO) and Sub-retinal Neovascularization associated with Pathological Myopia (PM). Results: the review confirms that, when speaking of drug classes, treatment algorithms or patient profiles, different agents of the same therapeutic class can result in variable efficacies or safety profiles. Th e clinical relevance represented by the adequate assessment of post-treatment results must be considered, but specially, the careful screening to determine the most appropriate agent and regimen in the intention-to-treat a patient. Though recommendations and treatment guidelines for pathologies exist, protocols in individualized management and exposure of these real-life experiences are necessary, since not all patients or all retinal diseases respond in the same way to each therapeutic agent. Conclusion: Efficacy and safety using anti-VEGF therapies are extremely important when it comes to providing truly patient-centered care. There is no therapeutic solution, intervention or alternative that fits all complex ocular diseases, so it is important to weigh the available evidence, the experience and the expectations of both patients and prescribers. Th is will allow to get access to the appropriate therapeutic alternatives, in a timely manner, always considering the efficacy and safety profiles, active pharmacovigilance and the costs associated with the therapeutic alternatives used locally

    An update on site search activities for SWGO

    Full text link
    The Southern Wide-field Gamma-ray Observatory (SWGO) is a project by scientists and engineers from 14 countries and 78 institutions to design and build the first wide-field, ground-based gamma-ray observatory in the Southern Hemisphere, with high duty cycle and covering an energy range rom hundreds of GeV to the PeV scale. The observatory will cover the Southern sky and aims to map the Galaxy's large-scale emission, as well as detecting transient and variable phenomena. The host sites under consideration are at a minimum altitude of 4400 m.a.s.l. and comprise two types: flat plateaus of at least 1 km2^{2} for the installation of an array of tank-based water Cherenkov detectors (WCD), or large natural lakes for the direct deployment of WCD units. Four South American countries proposed excellent sites to host the observatory meeting these requirements. Argentina proposed two locations in the Salta province, Bolivia presented one site in Chacaltaya, Chile two locations within the Atacama Astronomical Park, and Peru two ground-based locations in the Arequipa district as well as lakes in the Cuzco region. The SWGO collaboration is currently conducting a site characterization study, gathering all the necessary information for site shortlisting and final site selection by the end of 2023. The process has reached the shortlisting phase, in which primary and backup sites for each country have been identified. The primary sites were visited by a team of experts from the collaboration, to investigate and validate the proposed site characteristics. Here we present an update on these site selection activities.Comment: In Proceedings of the 2023 ICRC, Nagoya, Japa

    Simulation of the CMS Resistive Plate Chambers

    Full text link
    The Resistive Plate Chamber (RPC) muon subsystem contributes significantly to the formation of the trigger decision and reconstruction of the muon trajectory parameters. Simulation of the RPC response is a crucial part of the entire CMS Monte Carlo software and directly influences the final physical results. An algorithm based on the parametrization of RPC efficiency, noise, cluster size and timing for every strip has been developed. Experimental data obtained from cosmic and proton-proton collisions at s=7\sqrt{s}=7 TeV have been used for determination of the parameters. A dedicated validation procedure has been developed. A good agreement between the simulated and experimental data has been achieved.Comment: to be published in JINS

    Defective Lipid Droplet-Lysosome Interaction Causes Fatty Liver Disease as Evidenced by Human Mutations in TMEM199 and CCDC115

    Get PDF
    BACKGROUND &amp; AIMS: Recently, novel inborn errors of metabolism were identified because of mutations in V-ATPase assembly factors TMEM199 and CCDC115. Patients are characterized by generalized protein glycosylation defects, hypercholesterolemia, and fatty liver disease. Here, we set out to characterize the lipid and fatty liver phenotype in human plasma, cell models, and a mouse model.METHODS AND RESULTS: Patients with TMEM199 and CCDC115 mutations displayed hyperlipidemia, characterized by increased levels of lipoproteins in the very low density lipoprotein range. HepG2 hepatoma cells, in which the expression of TMEM199 and CCDC115 was silenced, and induced pluripotent stem cell (iPSC)-derived hepatocyte-like cells from patients with TMEM199 mutations showed markedly increased secretion of apolipoprotein B (apoB) compared with controls. A mouse model for TMEM199 deficiency with a CRISPR/Cas9-mediated knock-in of the human A7E mutation had marked hepatic steatosis on chow diet. Plasma N-glycans were hypogalactosylated, consistent with the patient phenotype, but no clear plasma lipid abnormalities were observed in the mouse model. In the siTMEM199 and siCCDC115 HepG2 hepatocyte models, increased numbers and size of lipid droplets were observed, including abnormally large lipid droplets, which colocalized with lysosomes. Excessive de novo lipogenesis, failing oxidative capacity, and elevated lipid uptake were not observed. Further investigation of lysosomal function revealed impaired acidification combined with impaired autophagic capacity.CONCLUSIONS: Our data suggest that the hyperchole-sterolemia in TMEM199 and CCDC115 deficiency is due to increased secretion of apoB-containing particles. This may in turn be secondary to the hepatic steatosis observed in these patients as well as in the mouse model. Mechanistically, we observed impaired lysosomal function characterized by reduced acidification, autophagy, and increased lysosomal lipid accumulation. These findings could explain the hepatic steatosis seen in patients and highlight the importance of lipophagy in fatty liver disease. Because this pathway remains understudied and its regulation is largely untargeted, further exploration of this pathway may offer novel strategies for therapeutic interventions to reduce lipotoxicity in fatty liver disease.</p
    corecore