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1.
Opt Express ; 31(3): 3504-3519, 2023 Jan 30.
Article in English | MEDLINE | ID: mdl-36785342

ABSTRACT

Nowadays, atom-based quantum sensors are leaving the laboratory towards field applications requiring compact and robust laser systems. Here we describe the realization of a compact laser system for atomic gravimetry. Starting with a single diode laser operating at 780 nm and adding only one fiber electro-optical modulator, one acousto-optical modulator and one laser amplifier we produce laser beams at all the frequencies required for a Rb-87 atomic gravimeter. Furthermore, we demonstrate that an atomic fountain configuration can also be implemented with our laser system. The modulated system reported here represents a substantial advance in the simplification of the laser source for transportable atom-based quantum sensors that can be adapted to other sensors such as atomic clocks, accelerometers, gyroscopes or magnetometers with minor modifications.

2.
Phys Rev E ; 103(4-1): 043004, 2021 Apr.
Article in English | MEDLINE | ID: mdl-34005940

ABSTRACT

The counterintuitive fact that wave chaos appears in the bending spectrum of free rectangular thin plates is presented. After extensive numerical simulations, varying the ratio between the length of its sides, it is shown that (i) frequency levels belonging to different symmetry classes cross each other and (ii) for levels within the same symmetry sector, only avoided crossings appear. The consequence of anticrossings is studied by calculating the distribution of the ratio of consecutive level spacings for each symmetry class. The resulting ratio distributions disagree with the expected Poissonian result. They are then compared with some well-known transition distributions between Poisson and the Gaussian orthogonal random matrix ensemble. It is found that the distribution of the ratio of consecutive level spacings agrees with the prediction of the Rosenzweig-Porter model. Also, the normal-mode vibration amplitudes are found experimentally on aluminum plates, before and after an avoided crossing for symmetrical-symmetrical, symmetrical-antisymmetrical, and antisymmetrical-symmetrical classes. The measured modes show an excellent agreement with our numerical predictions. The expected Poissonian distribution is recovered for the simply supported rectangular plate.

5.
Talanta ; 60(2-3): 335-44, 2003 Jun 13.
Article in English | MEDLINE | ID: mdl-18969056

ABSTRACT

This paper addresses an attempt to overcome the deviation that results from the use of a solid phase extraction (SPE) procedure for extracting trace levels of three benzimidazole pesticides (carbendazim, fuberidazole and thiabendazole) from water samples, for their subsequent quantitative determination by spectrofluorimetry, using univariate calibration. The deviation is due to an attenuation effect originating in the C(18) cartridge used in the SPE step. The approach developed is based on the calculation of a correction factor (fc) that is dependent on the signal measured after the SPE step. In order to calculate fc a study of the intermediate precision of two calibration graphs (with and without SPE) was performed. The fc was added to the predicted concentrations for the analytes using a calibration graph for pure solvent, built every time that the analysis is done. In addition, predictions were made using both average calibration graphs obtained from the intermediate precision study. In this study, the first of these three options was shown to improve the accuracy of predictions in the presence of matrix effects.

6.
An Med Interna ; 19(9): 457-9, 2002 Sep.
Article in Spanish | MEDLINE | ID: mdl-12420630

ABSTRACT

Lymphomas of the gastrointestinal tract are the most common type of primary extranodal lymphomas and about 15-20% of these are primary intestinal lymphomas. They may be or B or T- cell. Intestinal T-cell lymphomas are much less common and they can be enteropathy-associated. This disease occurs in adults with abdominal pain often associated with intestinal perforation. The course is aggressive. The major problem is to distinguish this disease from a benign ulcer. Two cases with differents clinical and pathologic features are reported with a review in the literature of this uncommon entity.


Subject(s)
Intestinal Neoplasms/pathology , Lymphoma, T-Cell/pathology , Adult , Humans , Intestinal Neoplasms/diagnosis , Lymphoma, T-Cell/diagnosis , Male , Middle Aged
7.
An. med. interna (Madr., 1983) ; 19(9): 457-459, sept. 2002.
Article in Es | IBECS | ID: ibc-17183

ABSTRACT

Los linfomas del tracto gastrointestinal son el tipo más frecuente de linfomas extraganglionares y de éstos el 15-20 per cent son de localización intestinal. Pueden ser B o T. Los linfomas tipo T son menos comunes y pueden estar o no asociados a enteropatía. Suelen aparecer en adultos en forma de dolor abdominal a menudo asociado a perforación intestinal. El curso es agresivo. El mayor problema es hacer el diagnóstico diferencial con las úlceras benignas. Se presentan dos casos de diferentes características y evolución y que permiten realizar una revisión de las características clinicopatológicas de esta rara entidad. (AU)


Subject(s)
Middle Aged , Adult , Male , Humans , Lymphoma, T-Cell , Intestinal Neoplasms
9.
Oncología (Barc.) ; 24(7): 372-375, jul. 2001. ilus, tab
Article in Es | IBECS | ID: ibc-15311

ABSTRACT

Propósito: El linfoma primario óseo es una rara forma de linfoma extranodal que representa menos de un 1 por ciento de los linfomas no Hodgkin. Su diagnóstico puede ser difícil por los síntomas de presentación y las características radiológicas, a veces similares a las de otras enfermedades óseas. En general tiene un buen pronóstico tras el tratamiento aunque éste no ha sido completamente definido. Material y métodos: Se presentan dos pacientes que presentaron esta enfermedad pero con distintas edades, síntomas y localización del tumor. Resultados y conclusiones: Estos casos permiten tener la oportunidad de revisar esta infrecuente neoplasia que tiene una supervivencia libre de enfermedad a los ocho años cercana al 100 por ciento (AU)


Subject(s)
Adult , Aged , Female , Male , Humans , Lymphoma, Non-Hodgkin , Review
11.
Oncología (Barc.) ; 24(4): 185-191, abr. 2001. tab
Article in Es | IBECS | ID: ibc-15264

ABSTRACT

La evaluación económica ha ido adquiriendo una gran importancia dentro de la Medicina y se han desarrollado diferentes estudios famacoeconómicos con distinto impacto en la práctica clínica. Los costes directos de los enfermos con cáncer se sitúan en torno a un 10 porciento del total de los costes médicos por lo que este énfasis ha influido también en los estudios oncológicos. Desafortunadamente, a pesar del aumento de los análisis económicos publicados en la literatura, es difícil saber todavía cuál es el impacto real en Oncología. En este articulo se revisan los conceptos básicos de farmacoeconomía y una visión general de su aplicación en la práctica oncológica (AU)


Subject(s)
Humans , Economics, Pharmaceutical/trends , Medical Oncology/economics
12.
Oncología (Barc.) ; 23(1): 37-40, ene. 2000. Tab
Article in Es | IBECS | ID: ibc-15184

ABSTRACT

Propósito: Valorar la eficacia y seguridad del esquema Carboplatino -Tegafur- Leucovorín como tratamiento quimioterápico en el cáncer de mama avanzado. Material y métodos: Entre 1992-97 fueron tratadas con este régimen 19 pacientes (entre 34 y 76 años) con metástasis en distintas localizaciones y que habían recibido ya una o más líneas previas de quimioterapia. Resultados: Se administraron entre 1 y 12 ciclos por paciente. Las principal toxicidad fue: neutropenio, anemia y trombopenia y naúseas y vómitos. No ocurrieron muertes tóxicas. Hubo 1 remisión completa y 4 remisiones parciales. ConcIusiones: El régimen Carboplatino -Tegafur- Leucovorín es moderadamente eficaz como tratamiento de segunda o tercera línea en el cáncer de mama avanzado. La toxicidad, fundamentalmente hematológica, no es demasiado elevada por lo que puede ser una opción más de tratamiento en esos casos (AU)


Subject(s)
Adult , Aged , Female , Middle Aged , Humans , Carboplatin/therapeutic use , Carboplatin/adverse effects , Tegafur/therapeutic use , Tegafur/adverse effects , Leucovorin/therapeutic use , Leucovorin/adverse effects , Breast Neoplasms/drug therapy , Drug Therapy, Combination
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