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The influence of the window shape in the frequency response of electromagnetic crystals (ECs), made by etching a sinusoidal continuous pattern of constant period and variable amplitude on the ground plane of a microstrip line, is studied in terms of rejection level, bandwidth, side-lobe level, and stopband abruptness. A new parameter, the equivalent number of periods, is found to be a good estimate of the increase in length needed to maintain the rejection level and bandwidth of the uniform structure, while reducing the secondary lobes by applying a window. © 2002 Wiley Periodicals, Inc. Microwave Opt Technol Lett 36: 37–40, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10663 [ABSTRACT FROM AUTHOR]

A way to model and test fiber gratings and fiber grating-based systems in the microwave range is proposed. The method rests on the equivalence relationship found between a fiber grating and a one-dimensional microstrip photonic bandgap structure that consists of a periodic pattern of circles etched in its ground plane. The equivalence assures that the frequency-response of the fiber grating is an upshifted replica of the corresponding frequency to its equivalent microstrip device. Both apodized and nonapodized uniform fiber gratings have been considered and the feasibility of the proposed method has been shown in simulation and measurement. [ABSTRACT FROM AUTHOR]

Background: Retrospective study of the varicella pneumonia in adults, in order to know incidence, environmental and clinical characteristics and treatments of patients with this diagnosis during the last 9 years in Toledo., Material and Methods: Twenty-one adult patients with the diagnosis of varicella pneumonia were studied, using the information of clinical histories and codified data. The backgrounds of pregnancy, smoking habit, concomitant diseases, previous contacts with another patients and the season of the year, were evaluated. Diagnosis was established by clinical and radiologic criteria in the course of varicella infection., Results: 21 patients (10 males and 11 females, between 25 and 73 years) were studied. 17 (81%) were smokers, in 15 (71.4%) there was documented contact with varicella infection and 4 (19%) were immunocompromised. In the first 3-7 days after the development of skin lesions (100%), there was fever in 20 cases (95.2%) and dyspnea in 14 (66.7%). There were 4 patients (33,3%) without respiratory symptoms and in 5 (23,8%) there was important hypoxemia. Evolution was satisfactory in 20 cases (95.2%); three others requiring admission to Intensive Care Unit. Chest X-ray revealed an interstitial pattern in 11 cases (52.4%), nodular in 4 (19%) and a mixed pattern in 5 (23.8%). 20 patients were treated with acyclovir and in one case with foscarnet. In 28.57% cases, corticosteroids were needed., Conclusions: We believe smoking habit could be a risk factor related to an increase of varicella pneumonia. A chest X-ray should be made in every patient, despite the symptoms. Adults with pneumonia have a better prognosis if acyclovir is started early in time. Concomitant treatment with corticosteroids should be used in those cases with respiratory insufficiency.

We introduce a novel concept in Brillouin signal processing based on modification of the optical carrier's magnitude and phase by stimulated Brillouin scattering-induced depletion. The technique offers wideband processing and low noise and requires only low optical power. Application to the enhancement of a 25-km high-frequency analog link is experimentally demonstrated and yields a 6.5-GHz bandwidth extension and a 13-dB reduction in the link insertion loss without intermodulation distortion.

We demonstrate a new concept in optical carrier control that uses a simple arrangement based on a hybrid Brillouin-erbium fiber laser. The system offers precise tunable control of the optical carrier amplitude independently of the characteristics of the transmitter or the optical modulation format. As much as 55 dB of carrier attenuation is demonstrated, which to our knowledge is the highest reported attenuation for a carrier-suppression system.