RESUMEN
We explore a class of quantum control operations based on a wide family of harmonic magnetic fields that vary softly in time. Depending on the magnetic field amplitudes taking part, these control operations can produce either squeezing or loop (orbit) effects, and even parametric resonances, on the canonical variables. For these purposes we focus our attention on the evolution of observables whose dynamical picture is ascribed to a quadratic Hamiltonian that depends explicitly on time. In the first part of this work we survey such operations in terms of biharmonic magnetic fields. The dynamical analysis is simplified using a stability diagram in the amplitude space, where the points of each region will characterise a specific control operation. We discuss how the evolution loop effects are formed by fuzzy (non-commutative) trajectories that can be closed or open, in the latter case, even hiding some features that can be used to manipulate the operational time. In the second part, we generalise the case of biharmonic fields and translate the discussion to the case of polyharmonic fields. Using elementary properties of the Toeplitz matrices, we can derive exact solutions of the problem in a symmetric evolution interval, leading to the temporal profile of those magnetic fields suitable to achieve specific control operations. Some of the resulting fuzzy orbits can be destroyed by the influence of external forces, while others simply remain stable.
RESUMEN
INTRODUCTION: Glomerular disease is among the top ten leading causes of death in Mexico. AIM: To assess the frequency of glomerulopathy in western Mexico in a Regional Hospital belonging of the Instituto Mexicano Del Seguro Social. METHODS: Single hospital center retrospective analysis. We reviewed all native kidney biopsies between January 2003 and December 2011, in patients more than 16 years old, to establish clinical features, presentation, and histological report. RESULTS: A total of 163 reports were analyzed; patients with a mean age of 32.6 ± 13.3 years, 55% female, 24% had systemic arterial hypertension, and 10% with a family history of chronic renal failure. The most frequent types of primary glomerulonephritis were focal segmental glomerulosclerosis (FSGS) in 47% of cases, followed by membranous nephropathy in 15%. The most frequent types of secondary glomerulonephritis were lupus nephritis in 14%, followed by diabetic nephropathy in 4% and amyloidosis in 1.2%. CONCLUSION: Focal segmental glomerulosclerosis is the most frequent type of glomerulopathy in our population; we observed a minor percentage of Inmunoglobulin A (IgA) nephropathy compared with worldwide reports. This information is a contribution to the understanding of the prevalence of glomerulopathy in western Mexico.
Asunto(s)
Glomerulonefritis/epidemiología , Glomeruloesclerosis Focal y Segmentaria/epidemiología , Enfermedades Renales/epidemiología , Adolescente , Adulto , Biopsia , Bases de Datos Factuales , Femenino , Glomerulonefritis/fisiopatología , Humanos , Hipertensión/epidemiología , Enfermedades Renales/fisiopatología , Masculino , México/epidemiología , Persona de Mediana Edad , Prevalencia , Estudios Retrospectivos , Adulto JovenRESUMEN
Se describe un caso de Aplasia Eritroide Pura en un lactante menor de 6 meses de edad, sexo masculino, quien presentaba palidez cutáneo-mucosa generalizada progresivae inapetencia. No se apreciaron anomalias congénitas. En la biopsia madular se apreció depresión de la serie eritrocítica. Las otras series medulares se conservaban normales. Se revisa la literatura al respecto discutiendo las caracteristicas clínicas de la enfermedad así como el tratamiento de la misma