Non-unitary representations of the SU(2) algebra in the Dirac equation with a Coulomb potential

A novel realization of the classical SU(2) algebra is introduced for the Dirac relativistic hydrogen atom defining a set of operators that, besides, allow the factorization of the problem. An extra phase is needed as a new variable in order to define the algebra. We take advantage of the operators to solve the Dirac equation using algebraic methods. To acomplish this, a similar path to the one used in the angular momentum case is employed; hence, the radial eigenfuntions calculated comprise non unitary representations of the algebra. One of the interesting properties of such non unitary representations is that they are not labeled by integer nor by half-integer numbers as happens in the usual angular momentum representation.Comment: 20 pages 1 eps figure in a single zipped file, submitted to J. Math. Phy

Axion dark matter in a 3-3-1 model

FAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCAPES - COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL E NÍVEL SUPERIORSlightly extending a right-handed neutrino version of the 3 - 3 - 1 model, we show that it is not only possible to solve the strong CP problem but also to give the total dark matter abundance reported by the Planck collaboration. Specifically, we consider the possibility of introducing a 3 - 3 - 1 scalar singlet to implement a gravity stable Peccei-Quinn mechanism in this model. Remarkably, for allowed regions of the parameter space, the arising axions with masses m(a) approximate to meV can both make up the total dark matter relic density through nonthermal production mechanisms and be very close to the region to be explored by the IAXO helioscope.976112FAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCAPES - COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL E NÍVEL SUPERIORFAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCAPES - COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL E NÍVEL SUPERIOR2014/19164-6Sem informaçã

Diffusion on a solid surface: Anomalous is normal

We present a numerical study of classical particles diffusing on a solid surface. The particles' motion is modeled by an underdamped Langevin equation with ordinary thermal noise. The particle-surface interaction is described by a periodic or a random two dimensional potential. The model leads to a rich variety of different transport regimes, some of which correspond to anomalous diffusion such as has recently been observed in experiments and Monte Carlo simulations. We show that this anomalous behavior is controlled by the friction coefficient, and stress that it emerges naturally in a system described by ordinary canonical Maxwell-Boltzmann statistics

New non-unitary representations in a Dirac hydrogen atom

New non-unitary representations of the SU(2) algebra are introduced for the case of the Dirac equation with a Coulomb potential; an extra phase, needed to close the algebra, is also introduced. The new representations does not require integer or half integer labels. The set of operators defined are used to span the complete space of bound state eigenstates of the problem thus solving it in an essentially algebraic way

BIOPSIA DE ENCIA EN EL DIAGNOSTICO DE LA MICROANGIOPATIA DIABETICA

A study was made of gingival biopsies perfomed in 42 patients, 24 of the patients. Were diabetics and 18 were non diabeties used as controls. Capillary lesions were found in all diabetic patients. These lesions varied from a minimal thickening of the basement membrane. This thickening was P.A.S. positive. In 90% of the diabetic patients a thickening of the nodular type in the walls of the thickened capillaries and too were fonud a series of pictures of transition between the diffuse, more or less irregular thickening and the appearance of these modular images was noticed; these lesions showed an irregular eosinophilia. The stains used showed that these nodular formations react in the same way as the nodular lesions of the diabetic glomerulies. The authours consider these gingival lesions another manifestation of the generalized vascular damage which is thought to be to the same pathogenic mechanism and to be another manifestation of diabetic microangyopathy.Se hizo un estudio de biópsia gíngivales realizadas en 42 pacientes, 24 de los pacientes diabéticos y 18 no lo fueron sino utilizados como controles. Se encontraron lesiones capilares en todos los pacientes diabéticos. Estas lesiones variaron desde un espesor mínimo de la membrana basal profunda. Este espesor fue PAS positivo. En el 90% de los pacientes diabéticos se encontró una espesura de tipo nodular (acumulación de glicoproteinas) en las paredes de los capilares, asi como también se encontraron una serie de cuadros de transición entre los difusos; se notó más o menos una espesura irregular y una apariencia de éstas imágenes irregulares nodulares. Estas lesiones mostraron eosinofilia irregular. Los tintes que se utilizaron mostraban que estas formaciones nodulares de los glomérulas diabéticos. Los autores consideran que estas lesiones gingivales como otra manifestación del daño vascular generalizado que probablemente ocurre en diabéticos y que se presume que sea el mismo mecanismo patogénico y también otra manifestación de la microangiopatia diabética

Análisis de calidad de las observaciones GPS en estaciones de operación continua de libre acceso en México

Se realizó la evaluación estadística-comparativa de 65 estaciones de operación continua de libre acceso en México, de enero de 2010 a enero de 2020. El análisis de calidad de las observaciones GPS se llevó a cabo mediante el software TEQC, desarrollado por UNAVCO, considerando cuatro indicadores de calidad en 6 variables: efecto multitrayectoria en la banda L1 y L2, relación señal-ruido en L1 y L2, saltos de ciclo por cada mil observaciones y porcentaje de observaciones registradas/esperadas. El resultado de cada estación se comparó con el estándar de calidad establecido por el IGS para pertenecer a su red, con la finalidad de determinar la calidad de las mismas y el grado de cumplimiento de dicho estándar. Los resultados muestran, en promedio, un grado de cumplimiento de 3.3 de las 6 variables, donde: 6 estaciones cumplen con 5 de las 6 variables; 16 estaciones con 4; 35 con 3; 6 con 2 y 2 con una variable, siendo la estación INEG la de mejor calidad excepto en los saltos de ciclo por cada mil observaciones. Así mismo, se muestra que el efecto multitrayectoria se presenta en mayor cantidad en aquellas estaciones en las que no se realizó cambio de antena, receptor o actualización de firmware, degradando principalmente la recepción de la señal en la banda L2.  A statistical comparative evaluation of 65 continuously operating, free access stations in Mexico was made. The observations were performed from January 2010 to January 2020. The quality check of the GPS observations was carried out by using TEQC software, developed by UNAVCO. Four quality indexes were considered within the quality check, with six variables: multipath effect on L1 and L2 band, percentage of registered/expected observations, signal-to-noise ratio on L1 and L2, and cycle slip per 1000 observations. The results obtained from each station were compared with the quality standard established by IGS in order to belong to its network, this with the goal of determining their quality and the level of meeting the standard. The results show, on average, a meeting 3.3 of the 6 variables, where: 6 stations meet 5 of 6 variables; 16 stations with 4; 35 stations with 3; 6 stations with 2 and 2 station with one variable, being INEG station the best in the quality check except for the cycle slips per 1000 observations. Likewise, it was shown that the multipath effect is greater in those stations that had not antenna/receiver changing or firmware update, mainly degrading the received signal on the L2 band

Tumor urotelial de vejiga en la infancia: reporte de un nuevo caso

Introduction: bladder tumors are rare in childhood, only 0.38% of cases belong to people younger than 20 years prevailing the mesodermic origin. Considering those of epithelial origin, more than 100 cases have been diagnosed since 1950, mostly with superficial lesions, benign behavior, more common in males (ratio male / female 5/1 to 7/1), and its etiology has not yet been clarified. Case presentation: it is reported the case of a 15-year-old black teenager who came to our hospital with a total painless haematuria with no other associated symptoms. After some studies like transabdominal ultrasound and cystoscopy with biopsy it was found that he had a malignant tumor of the vesical urothelium. Discussion: papillomatous vesical tumor in the right lateral side of the bladder, away from the urethral meatus with approximately 2 cm of diameter and narrow base similar to bladder mucosa coloration. Partial cystectomy was performed evolving without complications. Conclusions: urothelial tumors in the pediatric population are extremely rare, its biological behavior is less aggressive than the one in the adult population, and the election treatment is the Trans urethral resection.Introducción: los tumores vesicales son infrecuentes en la infancia, solo un 0,38% de los casos corresponden a menores de 20 años, prevaleciendo los de origen mesodérmico. Considerando aquellos de estirpe epitelial, algo más de 100 casos han sido diagnosticados desde 1950, tratándose, en su gran mayoría, de lesiones superficiales, de comportamiento benigno, más frecuentes en varones (cociente hombre/mujer de 5/1 a 7/1), su etiología aún no ha sido aclarada.Presentación de caso: se reporta el caso de un adolescente de 15 años de edad raza negra que acude a nuestro hospital por hematuria total indolora, sin otros síntomas asociados. Después de los estudios realizados como Ecografía transabdominal y Cistoscopia con biopsia se comprueba que presentaba una tumoración maligna del urotelio vesical.Discusión:tumoración vesical de aspecto papilomatoso, en la cara lateral derecha de la vejiga alejada del meato ureteral, de aproximadamente 2 cm de diámetro, de base estrecha y de coloración similar a la mucosa de vejiga. Se le realizo Cistectomía parcial evolucionando sin complicaciones.Conclusiones: los tumores uroteliales en la población pediátrica, son extremadamente raros, su comportamiento biológico es menos agresivo que el que tienen en la población adulta, el tratamiento de elección es la Resección Tran­suretral

Gas monitoring methodology and application to CCS projects as defined by atmospheric and remote sensing survey in the natural analogue of Campo de Calatrava

CO2 capture and storage (CCS) projects are presently developed to reduce the emission of anthropogenic CO2 into the atmosphere. CCS technologies are expected to account for the 20% of the CO2 reduction by 2050. Geophysical, ground deformation and geochemical monitoring have been carried out to detect potential leakage, and, in the event that this occurs, identify and quantify it. This monitoring needs to be developed prior, during and after the injection stage. For a correct interpretation and quantification of the leakage, it is essential to establish a pre-injection characterization (baseline) of the area affected by the CO2 storage at reservoir level as well as at shallow depth, surface and atmosphere, via soil gas measurements. Therefore, the methodological approach is important because it can affect the spatial and temporal variability of this flux and even jeopardize the total value of CO2 in a given area. In this sense, measurements of CO2 flux were done using portable infrared analyzers (i.e., accumulation chambers) adapted to monitoring the geological storage of CO2, and other measurements of trace gases, e.g. radon isotopes and remote sensing imagery were tested in the natural analogue of Campo de Calatrava (Ciudad Real, Spain) with the aim to apply in CO2 leakage detection; thus, observing a high correlation between CO2 and radon (r=0,858) and detecting some vegetation indices that may be successfully applied for the leakage detection

Risk Factors in Patients with Kidney Cancer

Introducción: el adenocarcinoma renal descrito por Koing y conocido como tumor de Grawitz representa aproximadamente el 3 % de todas las neoplasias malignas en el ser humano y la proporción masculina femenina  de 2.1 resulta más frecuente en la zona urbana y la mayoría de los pacientes afectados se encuentran entre los 50 y 70 años a nivel internacional.Objetivo: identificar la influencia de determinados factores de riesgo en la aparición de esta enfermedad.Método: se realizó un estudio descriptivo y retroprospectivo donde se analizó el tratamiento quirúrgico del cáncer de riñón en el Hospital Provincial Universitario “Carlos Manuel de Céspedes”, desde Enero de 2008 a Enero 2013, distribuyendo los pacientes por edad y sexo, síntomas encontrados, tratamiento realizado, metástasis y tiempo de sobrevida. Resultados: se determinó que dicho cáncer fue más frecuente en el sexo femenino  entre 50 y 59 años. El síntoma predomínate fue el dolor lumbar y hematuria. Las metástasis más frecuentes fueron en Hígado y partes blandas. Los fallecidos fueron de 4 pacientes, 3 mujeres y un hombre.Conclusiones: el proceder terapéutico utilizado con mayor frecuencia fue la nefrectomía radical; la infección urinaria predomino como complicación. Resultó el carcinoma de células claras el tipo histológico que prevaleció. La supervivencia  fue mayor en el sexo masculino. El tumor renal derecho predomino sobre el izquierdo.Introduction: renal adenocarcinoma described by Koing and known as Grawitz tumor represents approximately 3% of all malignant neoplasias in human beings and the female – male ratio of 2.1 is more frequent in the urban area and the most affected patients are between 50 and 70 years internationally. Objective: to identify the influence of certain risk factors in the onset of the disease. Method: it was performed a retro descriptive and prospective study where it was analyzed the surgical treatment of kidney cancer in the University Province Hospital "Carlos Manuel de Céspedes", since January 2008 to January 2013, distributing the patients according to age and sex, symptoms, treatment, metastasis and survival time. Results: it was found that the cancer was more frequent in women between 50 and 59 years. The prevailing symptoms were lumbar pain and hematuria. The most frequent metastases were in the liver and in soft parts. The deceased were 4 patients: 3 women and a man. Conclusions: the mostly used therapeutic procedure was the radical nephrectomy; the urinary infection prevailed as a complication. The clear cell carcinoma was the histological type that prevailed. Survival was greater in males. The right renal tumor prevailed on the left tumor