Concentrated Ground Plane Booster Antenna Technology for Multiband Operation in Handset Devices

The current demand in the handset antenna field requires multiband antennas due to the existence of multiple communication standards and the emergence of new ones. At the same time, antennas with reduced dimensions are strongly required in order to be easily integrated. In this sense, the paper proposes a compact radiating system that uses two non-resonant elements to properly excite the ground plane to solve the abovementioned shortcomings by minimizing the required Printed Circuit Board (PCB) area while ensuring a multiband performance. These non-resonant elements are called here ground plane boosters since they excite an efficient mode of the ground plane. The proposed radiating system comprises two ground plane boosters of small dimensions of 5 mm x 5 mm x 5 mm. One is in charge of the low frequency region (0.824-0.960 GHz) and the other is in charge of the high frequency region (1.710-2.170 GHz). With the aim of achieving a compact configuration, the two boosters are placed close to each other in a corner of the ground plane of a handset device (concentrated architecture). Several experiments related to the coupling between boosters have been carried out in two different platforms (barphone and smartphone), and the best position and the required matching network are presented. The novel proposal achieves multiband performance at GSM850/900/1800/1900 and UMTS

El Terreny físico-químic en la tuberculosi

A la part superior de la portada: Laboratori de Bioquímica de l'Escola Superior d'AgriculturaBibliografi

Solar cycle induced variations in GONG p-mode frequencies and splittings

We have analysed the recently available GONG p-mode frequencies and splitting coefficients for a period of three and half years, including the rapidly rising phase of solar cycle 23. The analysis of mean frequency shift with different activity indices shows that the shift is equally correlated with both magnetic and radiative indices. During the onset of the new cycle 23, we notice that the change in $b_4$ splitting coefficient is more prominent than the change in $b_2$. We have estimated the solar rotation rate with varying depth and latitude. In the equatorial region, the rotation first increases with depth and then decreases, while an opposite behaviour is seen in the polar region. We also find a small but significant temporal variation in the rotation rate at high latitudes.Comment: Uses aastex, To appear in Astrophysical Journal, October 10, 2000 issu

Reconciling the influence of task-set switching and motor inhibition processes on stop signal after-effects.

Executive response functions can be affected by preceding events, even if they are no longer associated with the current task at hand. For example, studies utilizing the stop signal task have reported slower response times to "GO" stimuli when the preceding trial involved the presentation of a "STOP" signal. However, the neural mechanisms that underlie this behavioral after-effect are unclear. To address this, behavioral and electroencephalography (EEG) measures were examined in 18 young adults (18-30 years) on "GO" trials following a previously "Successful Inhibition" trial (pSI), a previously "Failed Inhibition" trial (pFI), and a previous "GO" trial (pGO). Like previous research, slower response times were observed during both pSI and pFI trials (i.e., "GO" trials that were preceded by a successful and unsuccessful inhibition trial, respectively) compared to pGO trials (i.e., "GO" trials that were preceded by another "GO" trial). Interestingly, response time slowing was greater during pSI trials compared to pFI trials, suggesting executive control is influenced by both task set switching and persisting motor inhibition processes. Follow-up behavioral analyses indicated that these effects resulted from between-trial control adjustments rather than repetition priming effects. Analyses of inter-electrode coherence (IEC) and inter-trial coherence (ITC) indicated that both pSI and pFI trials showed greater phase synchrony during the inter-trial interval compared to pGO trials. Unlike the IEC findings, differential ITC was present within the beta and alpha frequency bands in line with the observed behavior (pSI > pFI > pGO), suggestive of more consistent phase synchrony involving motor inhibition processes during the ITI at a regional level. These findings suggest that between-trial control adjustments involved with task-set switching and motor inhibition processes influence subsequent performance, providing new insights into the dynamic nature of executive control

Tuberculosi

Peer Reviewe

GONG p-mode frequency changes with solar activity

We present a correlation analysis of GONG p-mode frequencies with nine solar activity indices for the period 1995 August to 1997 August. This study includes spherical harmonic degree in the range 2 to 150 and the frequency range of 1500-3500 \mu Hz. Using three statistical tests, the measured mean frequency shifts show strong to good correlation with activity indices. A decrease of 0.06 \mu Hz in frequency, during the descending phase of solar cycle 22 and an increase of 0.04 \mu Hz in the ascending phase of solar cycle 23 is observed. These results provide the first evidence for change in p-mode frequencies around the declining phase of solar cycle 22 and beginning of new cycle 23. This analysis further confirms that the temporal behaviour of the solar frequency shifts closely follow the phase of the solar activity cycle.Comment: 14 pages, 3 figures. To appear in Ap.

Aportacions experimentals a la fisiopatologia de la diabetis

A la part superior de la portada: Laboratori de Bioquímica de l'Escola Superior d'AgriculturaBibliografi

Patterns of Play in the Counterattack of Elite Football Teams - A Mixed Method Approach

This study aimed to detect and analyse regular patterns of play in football teams during their offensive phase, through the combination of the sequential analysis technique and semi-structured interviews of experienced first League Portuguese coaches. The sample included 36 games (12 per team) of the F.C. Barcelona, Internazionalle Milano, and Manchester United teams that were analysed through sequential analysis with the software SDIS-GSEQ. Based on the detected patterns, semi-structured interviews were carried out with 8 expert high-performance football coaches. Data were analysed through the content analysis technique using the software Nvivo 9. The detected patterns of play revealed specific characteristics of different philosophies of play. Through the performed content analysis we could observe that coaches interpreting play patterns mainly based their opinions on tactical-strategic and tactical-technical aspects, and on the characteristics of the players on their team. On the other hand, consideration was given to three of the main evolutionary trends of play/soccer practice, which focus on the development of exercises that cover: i) the connection between the four play moments (offensive/defensive organization and transitions); ii) the pre-programmed ball possession recovery; iii) the execution of set pieces