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A field hospital overseas requires various types of communication equipment. This study presents the communications equipment used by three Israeli field hospital delegations to earthquake sites at Adapazari, Turkey, in 1999, Port-au-Prince, Haiti, in 2010 and Minamisanriku, Japan, in 2011. The delegations to Turkey and Haiti were relatively large (105-230 personnel) and were on the site early (three to four days after each event). The 55-person delegation to Japan arrived later and was established as an outpatient community hospital. Standard military VHF radios were the only effective tool up to 5 km, until cellular coverage was regained (1-2 weeks after each event). International communication was good. While short-wave communication (telephone and Internet) was used in Turkey, a direct satellite channel was set up in Haiti. In Japan, BGAN Inmarsat provided efficient Wi-Fi for all needs. Motorola walkie talkies were not efficient beyond the immediate vicinity. This paper recommends continued use of military-specification equipment alongside newer modalities, particularly in situations where infrastructure is damaged.

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Comb filters are a class of low-complexity filters especially useful for multistage decimation processes. However, the magnitude response of comb filters presents a droop in the passband region and low stopband attenuation, which is undesirable in many applications. In this work, it is shown that, for stringent magnitude specifications, sharpening compensated comb filters requires a lower-degree sharpening polynomial compared to sharpening comb filters without compensation, resulting in a solution with lower computational complexity. Using a simple three-addition compensator and an optimization-based derivation of sharpening polynomials, we introduce an effective low-complexity filtering scheme. Design examples are presented in order to show the performance improvement in terms of passband distortion and selectivity compared to other methods based on the traditional Kaiser-Hamming sharpening and the Chebyshev sharpening techniques recently introduced in the literature.

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In this paper, we propose an in-service method to simultaneously monitor both nominal and effective values of differential group delay (DGD) in wavelength-division multiplexing (WDM) optical communication systems, in a per channel basis. The method is based on coherent heterodyne detection of the optical signal. We have demonstrated that the technique is capable to recover nominal DGD values from 0 ps to 90 ps while, at same time, to provide the effective DGD parameter, related to the impairment of optical channels. The relationship between the Q factor and effective DGD was also demonstrated, both numerically and experimentally, for distinct nominal values of DGD inserted on the system, by varying the state of polarization (SOP) of the optical signal at the input of the DGD element.

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Selective coupling a single pair of cores in a photonic crystal fiber with multiple, initially decoupled, cores is demonstrated through the use of a technique to locally post-process the fiber cross section. Coupling occurs when the hole between the selected core pair is collapsed over a short fiber section, which is accomplished by heating the section while the hole is submitted to an air pressure that is lower than that applied to all other holes in the microstructure. The demonstrated couplers present an estimated insertion loss of ~1 dB and exhibit spectral modulations with a depth of up to 18 dB and a high polarization sensitivity that can be exploited for polarization splitting or filtering in space-division-multiplexed optical interconnection and telecommunication links.

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OBJECTIVE: To report the experience of the Brazilian Program of Pediatric Teleradiology in combining teleconferencing and a virtual learning environment for services integration, collaborative research, and continuing education in pediatric radiology. MATERIALS AND METHODS: We performed virtual meetings from March 2005 to October 2010 on pediatric radiology-related themes, using a combination of videoconferences and Web conferences, which were recorded and made available in an open-source software (Moodle) for reuse. RESULTS: We performed 58 virtual sessions: 29 anatomical-clinical-radiological sessions, 28 on upgrading themes, and 1 virtual symposium. The average of connected points was 12 by videoconference and 39 by Web conference, and of 450 participants per event. At the time of this writing, 318 physicians and students are registered in the virtual learning environment, with a total of 14,678 accesses. CONCLUSIONS: Telemedicine is being included in pediatric radiology practice, as a means for distance education, training, and continuing integration between groups.

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The recovery of an optical carrier with the deletion of its amplitude modulation is introduced using a deeply saturated ultra-long semiconductor optical amplifier (UL-SOA). The experimental results were achieved for input signal bit rates up to 12.5 Gbps with high extinction ratio (up to 13.9 dB). The influence of parameters such as UL-SOA bias current, optical bandwidth, signal input power, modulation depth and bit rate are analyzed including the carrier spectral broadening effects due to the self-phase modulation effect.

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The telemedicine has increased mostly over recent years. Especially in developing countries where a high proportion of the population lives in rural areas or difficult to access. However it is successful implementation is closely connected with an appropriate design of the telecommunications network, part essential when deploying a network and the selection of appropriate communications technologies, realistic and sustainable according to the characteristics of the context in which it is deployed. This paper explain the situation of health centers in the municipalities Baruta and Hatillo in Venezuela, it proposes the design of a telemedicine network to allow interconnect the outpatient units with the referral hospital. Then it describes wireless technologies studied and finally it presents the entire design process of the network physical connection.

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BACKGROUND: Internet tools, cell phones, and other information and communication technologies are being used by HIV-positive people on their own initiative. Little is known about the perceptions of HIV-positive people towards these technologies in Peru. The purpose of this paper is to report on perceptions towards use of information and communication technologies as a means to support antiretroviral medication adherence and HIV transmission risk reduction. METHODS: We conducted a qualitative study (in-depth interviews) among adult people living with HIV in two community-based clinics in Peru. RESULTS: 31 HIV-positive individuals in Lima were interviewed (n = 28 men, 3 women). People living with HIV in Peru are using tools such as cell phones, and the Internet (via E-mail, chat, list-serves) to support their HIV care and to make social and sexual connections. In general, they have positive perceptions about using the Internet, cell phones and PDAs for HIV health promotion interventions. CONCLUSION: Health promotion interventions using information and communication technology tools among people living with HIV in resource-constrained settings may be acceptable and feasible, and can build on existing patterns of use.

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