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The photometric observations carried through 1997, 1998 and 1999 of the δ Sct-type variable HD 99002, were analysed. The photometry data was analyzed with AnaFre, a computing program. A preliminary frequency analysis was made on 2709 observed points in the Strömgren filter. The amplitudes of frequencies shown by the periodograms were found to be very close to the noise level, which questioned the reliability of the results.

Focal mechanism of 95 earthquakes for the period 1965-1985 with magnitud between 3.5 and 5.5 in south of Spain are studied. Fault-plane solutions for 16 individual events have been calculated [13 correspond to shallow earthquake (h < 30 km) and 3 to events with intermediate depth (30 < h < 150 km)]. Of the solutions, 6 correspond to normal faults, 4 to inverse faults and 3 to strike-slip faults. loint solutions have been calculated for 7 groups of earthquakes. They correspond, 5 to normal faults and 2 to inverse faults. The results have been correlated with the main geological faults in the area.En este trabajo, se presentan los mecanismos focales de terremotos ocurridos en el período 1965-1985 en el sur de España. Se han seleccionado 95 terremotos, cuya magnitud oscila entre 3,5 y 5,5. De ellos se han calculado el mecanismo focal individual de 16 terremotos, 13 corresponden a terremotos superficiales (h < 30 km) y 3 a terremotos de profundidad intermedia (30 < h < 150 km). De las soluciones obtenidas, 6 corresponden a fallas normales, 4 indican movimientos de fallas inversas, y 3 corresponden a fallas de desgarre. Se han calculado 7 soluciones conjuntas de grupos de terremotos, constituidos todos ellos por sismos superficiales. De estos mecanismos conjuntos, se han obtenido 5 soluciones que corresponden a falla normal y 2 a fallas inversas. Los resultados se correlacionan con las principales fracturas de la región, con el fin de interpretarlos desde el punto de vista sismotectónico.

Asymptomatic patients with severe coronary atherosclerosis may have a normal resting electrocardiogram and stress test.To assess the yield of Gated Single Photon Emission Computer Tomography (SPECT) for the screening of silent myocardial ischemia in type 2 diabetic patients.Electrocardiogram, stress test and gated-SPECT were performed on 102 type 2 diabetic patients aged 60+/-8 years without cardiovascular symptoms. AH subjects were also subjected to a coronary angiography whose results were used as gold standard.Gated-SPECT showed myocardial ischemia on 26.5% of studied patients. The sensibility, specificity accuracy, positive predictive value and negative predictive value were 92.3%, 96%, 95%, 88.8%, 97.3%, respectively. In four and six patients ischemia was detected on resting electrocardiogram and stress test, respectively. Eighty percent of patients with doubtful resting electrocardiogram results and 70% with a doubtful stress test had a silent myocardial ischemia detected by gated-SPECT There was a good agreement between the results of gated-SPECT and coronary angiography (k=0.873).Gated-SPECT was an useful tool for the screening of silent myocardial ischemia.

Background: Asymptomatic patients with severe coronary atherosclerosis may have a normal resting electrocardiogram and stress test. Aim: To assess the yield of Gated Single Photon Emission Computer Tomography (SPECT) for the screening of silent myocardial ischemia in type 2 diabetic patients. Material and methods: Electrocardiogram, stress test and gated-SPECT were performed on 102 type 2 diabetic patients aged 60 ± 8 years without cardiovascular symptoms. AH subjects were also subjected to a coronary angiography whose results were used as gold standard. Results: Gated-SPECT showed myocardial ischemia on 26.5% of studied patients. The sensibility, specifity accuracy, positive predictive value and negative predictive value were 92.3%, 96%, 95%, 88.8%, 97.3%, respectively. In four and six patients ischemia was detected on resting electrocardiogram and stress test, respectively. Eighty percent of patients with doubtful resting electrocardiogram results and 70% with a doubtful stress test had a silent myocardial ischemia detected by gated-SPECT There was a good agreement between the results of gated-SPECT and coronary angiography (k =0.873). Conclusions: Gated-SPECT was an useful tool for the screening of silent myocardial ischemia.

Background: Asymptomatic patients with severe coronary atherosclerosis may have a normal resting electrocardiogram and stress test. Aim: To assess the yield of Gated Single Photon Emission Computer Tomography (SPECT) for the screening of silent myocardial ischemia in type 2 diabetic patients. Material and methods: Electrocardiogram, stress test and gated-SPECT were performed on 102 type 2 diabetic patients aged 60 ± 8 years without cardiovascular symptoms. AH subjects were also subjected to a coronary angiography whose results were used as gold standard. Results: Gated-SPECT showed myocardial ischemia on 26.5% of studied patients. The sensibility, specifity accuracy, positive predictive value and negative predictive value were 92.3%, 96%, 95%, 88.8%, 97.3%, respectively. In four and six patients ischemia was detected on resting electrocardiogram and stress test, respectively. Eighty percent of patients with doubtful resting electrocardiogram results and 70% with a doubtful stress test had a silent myocardial ischemia detected by gated-SPECT There was a good agreement between the results of gated-SPECT and coronary angiography (k =0.873). Conclusions: Gated-SPECT was an useful tool for the screening of silent myocardial ischemia.

We have analysed ground-based multi-colour Stromgren photometry and single-filter photometry from the star tracker on the WIRE satellite of the delta scuti star Epsilon Cephei. The ground-based data set consists of 16 nights of data collected over 164 days, while the satellite data are nearly continuous coverage of the star during 14 days. The spectral window and noise level of the satellite data are superior to the ground-based data and this data set is used to locate the frequencies. However, we can use the ground-based data to improve the accuracy of the frequencies due to the much longer time baseline. We detect 26 oscillation frequencies in the WIRE data set, but only some of these can be seen clearly in the ground-based data. We have used the multi-colour ground-based photometry to determine amplitude and phase differences in the Stromgren b-y colour and the y filter in an attempt to identify the radial degree of the oscillation frequencies. We conclude that the accuracies of the amplitudes and phases are not sufficient to constrain theoretical models of Epsilon Cephei. We find no evidence for rotational splitting or the large separation among the frequencies detected in the WIRE data set. To be able to identify oscillation frequencies in delta scuti stars with the method we have applied, it is crucial to obtain more complete coverage from multi-site campaigns with a long time baseline and in multiple filters. This is important when planning photometric and spectroscopic ground-based support for future satellite missions like COROT and KEPLER., 13 pages, 12 figures, 4 tables. Fig. 4 reduced in quality. Accepted by A&A

A high-accuracy multisite campaign was carried out from 2002 January to May with a photometric coverage of 398 hours at five observatories. The concentration on a few selected sites gives better consistency and accuracy than collecting smaller amounts from a larger number of sites. 23 frequencies were detected with a high statistical significance. 6 of these are new. The 17 frequencies found in common with the 1992-1995 data are the modes with highest amplitudes. This indicates that the pulsation spectrum of FG Vir is relatively stable over the ten-year period. Two frequencies have variable amplitudes and phases from year to year as well as during 2002. These were both found to be double modes with close frequencies. For the mode at 12.15 c/d this leads to an apparent modulation with a time scale of about 129d. The close frequencies at 12.15 c/d are composed of a radial and a nonradial mode, suggesting a similarity with the Blazhko Effect seen in RR Lyrae stars., Comment: 8 pages, 4 figures, 2 tables

We have compiled a new extensive and updated list for δ Set variables including field SX Phe stars. More than 500 papers, published during the last few years, have been revised and a lot of new variables have been added to our last list (Rodríguez et al. 1994). The present catalogue is intended to be a comprehensive review on the observational characteristics of all the δ Set stars known until now, covering information published until the year 2000. The variables and their most relevant parameters are listed together with references to studies of individual stars and notes for a number of variables. Additionally to new variables, new catalogues on different parameters have been recently published. This information has been used to update each variable in our list, using the most recent catalogues available in the bibliography on photometry (Strömgren and Johnson systems), spectral types, rotational and radial velocities, multiplicity and parallaxes.

Analysis of uvby photometric observations of the δ Sct-type pulsator 29 Cyg is presented. The observations were carried out at the OSN (Spain) and SPM (Mexico) observatories during a coordinated observing season in 1996 together with an additional observing season at OSN in 1998. The measurements collected from both seasons were 2588 in each of the four uvby bands. Analysis of the data using Fourier Transform showed at least fourteen significant frequencies.

It has been pointed out by earlier authors that radial pulsation seems to be the only type present in high amplitude δ Sct stars, at least for monoperiodic stars. In order to confirm this or not, we have collected all the multicolor data available for these stars in the Strömgren and Johnson photometric systems. Then, the type of pulsation has been analysed on the basis of the phase shifts and amplitude ratios between observed light and colour variations. The results indicate that all the stars analysed, including both high amplitude δ Sct (Population I) and SX Phe (Population II) stars, are radial pulsators. This is also true for the monoperiodic medium amplitude δ Sct stars analysed., This research was supported by the Junta de Andalucía and Dirección General de Investigación Científica y Técnica (DGICYT) under project PB93-0134.

New uvby data collected of AN Lyn together with the reanalysis of old data establish that this star is a multiperiodic pulsator. Three independent frequencies (ν1=10.1756, ν2=18.1309 and ν3=9.5598 cd-1) and some interactions between them are found to be present in the light curve. Changes in amplitude with a large time scale are confirmed for the main frequency. Moreover, changes in amplitude are also present for the secondary frequencies, especially for ν3. After subtraction of the secondary frequencies from the light curves, the classical O-C method has been used to analyse the behaviour of the main period. A comparison is made between AN Lyn and the other two known δ Sct stars with atypical light curves, i.e., V1719 Cyg and V798 Cyg. New uvby data have been also collected for V1719 Cyg and the O-C method has been used to analyse the behaviour of the main period. It is found that the main pulsation of this star can be well described by means of a linear ephemeris with a period of P=0.d26729700 over the last eighteen years. Finally, analysis of the different data sets available in the literature do not reveal significative changes in the amplitude of the main frequency of V1719 Cyg., This research was supported by the Junta de Andalucía, the Dirección General de Investigación Científica y Técnica (DGICYT) under project PB93-0134 and CONACYT under project 400354-5-3925E.

Simultaneous uvbyβ photometric observations of the medium amplitude δ Sct star AN Lyn have been collected and new times of light maxima have been obtained. The Fourier transform and classical O-C methods are used to analyse the pulsation of this star. The light curves are peculiar in the sense that the descending branches are steeper than the ascending ones. Amplitude variations are shown to be present from season to season. The analysis of the phase shifts between observed light and colour variations suggests that this star is a radial pulsator. In addition, intrinsic b-y, m1 and c1 values are also derived and the physical parameters are determined indicating that this variable is a nearly cold and evolved δ Sct star showing solar metal abundances and pulsating in the second overtone., This research was supported by the Junta de Andalucía, the Dirección General de Investigación Científica y Técnica (DGICYT) under project PB93-0134 and CONACYT under project 400354-5-3925E