Simulation of the hydrogen ground state in Stochastic Electrodynamics

Stochastic electrodynamics is a classical theory which assumes that the physical vacuum consists of classical stochastic fields with average energy $\frac{1}{2}\hbar \omega$ in each mode, i.e., the zero-point Planck spectrum. While this classical theory explains many quantum phenomena related to harmonic oscillator problems, hard results on nonlinear systems are still lacking. In this work the hydrogen ground state is studied by numerically solving the Abraham -- Lorentz equation in the dipole approximation. First the stochastic Gaussian field is represented by a sum over Gaussian frequency components, next the dynamics is solved numerically using OpenCL. The approach improves on work by Cole and Zou 2003 by treating the full $3d$ problem and reaching longer simulation times. The results are compared with a conjecture for the ground state phase space density. Though short time results suggest a trend towards confirmation, in all attempted modelings the atom ionises at longer times.Comment: 20 pages, 9 figures. Published version, minor change

Red Iberoamericana de Toxicología y Seguridad Química

La Red Iberoamericana de Toxicología y Seguridad Química RITSQ, se inicia en marzo de 2008 y desde entonces ha tenido 69.930 visitas a la página web de la misma, se han registrado 1.133 personas de 41 países y desde entonces hemos realizado y presentado 66 carteles en Reuniones, Conferencias y Reuniones donde se mantienen de forma constante los Objetivos de la RITSQ: 1. Coordinar la participación de los diferentes grupos existentes en universidades y organismos de investigación de Iberoamérica, implicados en estudios relacionados con la Toxicología, 2. Fortalecer la colaboración y el intercambio académico entre los programas de Doctorado y Maestría de diferentes países iberoamericanos que tengan como objeto el estudio y la investigación en Toxicología o áreas relacionadas, 3. Favorecer la realización de proyectos de investigación conjuntos entre docentes e investigadores de Iberoamérica, pasantías estudiantiles y eventos académicos; 4. Profundizar en el estudio de métodos de ensayo de corta y larga duración utilizados en la evaluación de la carcinogenicidad, la mutagenicidad y la toxicidad para la reproducción de sustancias y mezclas de productos químicos, 5. Desarrollar y estandarizar métodos analíticos para la identificación y determinación de biomarcadores de exposición, efecto y .susceptibilidad para sustancias y productos químicos en el hombre y el medio ambiente; 6. Aplicar métodos de evaluación del riesgo para la salud humana y el medio ambiente de sustancias y productos químicos, 7. Fomentar el intercambio científico de profesionales interesados alimentaria; y 8. Propiciar el uso de métodos alternativos a la experimentación animal (www.remanet.net).Peer reviewe

Cycle-finite module categories

We describe the structure of module categories of finite dimensional algebras over an algebraically closed field for which the cycles of nonzero nonisomorphisms between indecomposable finite dimensional modules are finite (do not belong to the infinite Jacobson radical of the module category). Moreover, geometric and homological properties of these module categories are exhibited

Ochre use at Olieboomspoort, South Africa: insights into specular hematite use and collection during the Middle Stone Age

Recent excavations at Olieboomspoort (OBP) in the Waterberg Mountains of South Africa confirmed previous research at the site that highlighted an abundance of ochre in the Middle Stone Age (MSA) deposits. Here, we report on the results of an analysis of the ochre from the MSA deposits excavated in 2018-2019. Fossilised equid teeth from these deposits were recently dated to approximately 150 ka, an early date for such a sizeable ochre assemblage in southern Africa. Calcium carbonate concretions were removed from ochre pieces using hydrochloric acid. Macro- and microscopic analyses were undertaken to identify raw material types and to investigate utilisation strategies. There are 438 pieces in the assemblage and only 14 of them show definite use-traces. The predominant raw material is a micaceous, hard specular hematite, which is rare at MSA sites elsewhere in southern Africa. A preliminary investigation into the geological nature of the ochreous materials in the archaeological sample and those available in the area was performed using semi-quantitative portable X-ray fluorescence (pXRF), XRF, and inductively coupled plasma mass spectrometry (ICP-MS). Together with site formation processes, we suggest possible, primarily local sources of the ochre found in the deposits. The data do not support previous suggestions that OBP was used as an ochre caching site that may have formed part of an exchange network during the MSA. Instead, the local abundance of nodules of specular hematite within the Waterberg sandstone, the limited number of used pieces in the assemblage, and the stratigraphic context indicate a more natural, less anthropogenic explanation for the abundance of ochre at the site.European Social Fund (ESF) RYC2020-029506-Iinfo:eu-repo/semantics/publishedVersio

Leishmaniasis cutánea

We revise the main characteristics of cutaneous leishmaniasis, with particular reference to epidemiologycal, clinical and histological aspects, endèmic disease in Baleario Islands.Se revisan las principales características de la leishmaniasis cutánea, con especial referencia a los aspectos epidemiológicos, clínicos e histopatológicos, enfermedad endémica en las Islas Baleares

Exponential and moment inequalities for U-statistics

A Bernstein-type exponential inequality for (generalized) canonical U-statistics of order 2 is obtained and the Rosenthal and Hoffmann-J{\o}rgensen inequalities for sums of independent random variables are extended to (generalized) U-statistics of any order whose kernels are either nonnegative or canonicalComment: 22 page

Clinical characteristics associated with psychosocial functioning among patients with uncomplicated epilepsy in Spain

Objective To identify the clinical characteristics associated with poor psychosocial functioning among Spanish patients with epilepsy but no other neurological or psychiatric disorder. Methods Between May and September 2001 a survey among patients with epilepsy was carried out in 32 Spanish health care centres. The selection criteria of patients were attendance to a routine neurologist visit, to be aged between 25 and 64 and not having another additional neurological handicap (n = 812). Psychosocial function was elicited through six indicators: educational level, marital status, unemployment status, restricted car driving, self-perception of epilepsy as an important limiting factor in the educational level achieved and, among unemployed, as the cause of their unemployment. Multiple logistic regression models were fitted in order to calculate adjusted odds ratios (aOR) and their 95% confidence intervals. Results After simultaneously adjusting for socio-demographic variables and clinical characteristics, the six outcomes analysed increased with seizure frequency. Moreover, all the outcomes except low educational level were also related to early age at onset of epilepsy. Although no relation with objective educational level was found, there was a strong association between early age at onset of symptoms and self-perception of epilepsy as an important limiting factor of educational achievement. Conclusion These findings emphasize the need for more effective treatment of epilepsy and also highlight the importance of a psychosocial approach to management of epilepsy for patients with an early onset of symptoms in order to prevent social limitations in adult lif

Estudio paleontológico en las cuencas terciarias de Galicia

Se ha realizado una prospección paleontológica en nueve cuencas terciarias gnllegas, con el fin dc prccisar su edad y condiciones pnleoombiclltales. Presentamos los resultados obtenidos en base a hallazgos de micromamíferos, grandes mamíferos, peces, macrorestos vegetales y moluscos en las cuencas de As Pontes (A Coruila) y Roupar (Lugo). Las arci llas de los niveles inferiores de As Pontes contienen roedores, cuya edad corresponde al principio del Oligoceno superior (MP 25-26). Los lignitos inferiores han proporcionado un Antracotérido que probablemente corresponde también al Oligoceno. Las plantas de los niveles superiores pueden ser del Oligoceno o del Mioceno inferior. Las condiciones climáticas, siempre tropicales, debieron variar de cálidas a húmedas. En las arcillas inferiores hay peces y moluscos tanto dulceacuícolas como eurihalinos, y moluscos marinos litorales. Se apoyan con estos datos las hipótesis de contemporaneidad entre las cuencas de As Pontes y Roupar, y su carácter parálic