Fast Algorithms for TVAR and MTIE Computation in Characterization of Network Synchronization Performance

Time Variance (TVAR) and Maximum Time Interval Error (MTIE) are historically the main time-domain quantities for the specification of network synchronization performance in telecommunications standards. Nevertheless, plain computation of the TVAR and MTIE standard estimators proves cumbersome in most cases of practical interest, due to their heavy computational weight. In this paper, TVAR and MTIE are first introduced according to their standard definitions. Then, fast algorithms based on recursion and on binary decomposition to compute the TVAR and MTIE standard estimators are provided, which effectively cut down the number of operations needed. The MTIE algorithm based on binary decomposition reduces the number of operations needed to a term proportional to Nlog N instead of N . Both algorithms allow fast evaluation in most practical situations: even very long sequences of TE samples do not require more than few seconds of data processing for TVAR and MTIE computation

Synchronization of a WDM Packet-Switched Slotted Ring

In this paper, we present two different strategies of slot synchronization in wavelength-division-multiplexing (WDM) packet-switched slotted-ring networks. Emphasis is given to the architecture behind the WDM Optical Network Demonstrator over Rings (WONDER) project, which is based on tunable transmitters and fixed receivers. The WONDER experimental prototype is currently being developed at the laboratories of Politecnico di Torino. In the former strategy, a slotsynchronization signal is transmitted by the master station on a dedicated control wavelength; in the latter, slave nodes achieve slot synchronization aligning on data packets that are received from the master. The performance of both synchronization strategies, particularly in terms of packet-collision probability, was evaluated by simulation. The technique based on transmitting a timing signal on a dedicated control wavelength achieves better performance, although it is more expensive due to the need for an additional wavelength. However, the technique based on aligning data packets that are received from the master, despite attaining lower timing stability, still deserves further study, particularly if limiting the number of wavelengths and receivers is a major requirement. Some experimental results, which were measured on the WONDER prototype, are also shown. Measurement results, together with theoretical findings, demonstrate the good synchronization performance of the prototype

Allogeneic Stem Cell Transplantation for Solid Tumors: Which Way Forward?

AbstractThe patients presenting with metastatic solid tumors remains with poor prognosis. Despite advances in treatment and better understanding of the biological pathway during the past two decades, outcome remains often very poor. On the other hand, allogeneic stem cell transplantation has been established as a potent antitumoral immunotherapy in various hematological malignancies. Preliminary results confirm that graft versus tumor effect does exist. The main challenge is now to transform this biological and clinical effect into a real clinical benefit in term of curability and survival

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Block synchronization for quantum information

Locating the boundaries of consecutive blocks of quantum information is a fundamental building block for advanced quantum computation and quantum communication systems. We develop a coding theoretic method for properly locating boundaries of quantum information without relying on external synchronization when block synchronization is lost. The method also protects qubits from decoherence in a manner similar to conventional quantum error-correcting codes, seamlessly achieving synchronization recovery and error correction. A family of quantum codes that are simultaneously synchronizable and error-correcting is given through this approach.Comment: 7 pages, no figures, final accepted version for publication in Physical Review

Improving GFDM Symbol Error Rate Performance using Better than Nyquist Pulse Shaping Filters

Fourth generation (4G) cellular systems have been optimized to provide high data rates and reliable coverage to mobile users. New waveforms at the physical layer are needed. Generalized frequency division multiplexing (GFDM) is a candidate modulation for the fifth generation (5G) standard based on multi-branch multicarrier filter bank approach. A main characteristic of GFDM is its low out of band emission, achieved by means of a flexible time-domain pulse shaping of individual subcarriers. In this paper, the influence of the improved Better than Nyquist pulse shaping filters on symbol error rate (SER) performance of the GFDM system in the case of zero forcing (ZF) receiver is investigated. We considered their use in GFDM to evaluate the impact on SER performance in case of 16-QAM transmission over an additive white Gaussian noise channel. Moreover, we also considered the concept of the wavelet for better time-frequency localization of the pulse shaping filters by using the Meyer auxiliary function. Numerical results are reported to demonstrate the superior SER performance achieved

Consumo de antidepresivos y ansiolíticos en Argentina en 1998

Fundamentos: Realizar una estadística sobre el consumo de drogas antidepresivas y ansiolíticas durante el año 1998fin de obtener conclusiones que nos permitan aportar datos para racionalizar el uso.Método: Se obtuvieron los datos de distribución de las dos más grandes droguerías proveedoras de medicamentosde la Región del Nordeste Argentino y de las farmacias elaboradoras de prescripciones magistrales con éstos fármacos.Resultados: Los datos obtenidos fueron los siguientes: cantidad de unidades distribuidas por las droguerías expendedoras:18.080 de antidepresivos y 177.205 de ansiolíticos y de las oficinas de farmacia magistrales de la zona seobtuvieron la cantidad de recetas preparadas con estas drogas: 4440.Conclusiones: Se evidencia un predominio de la medicación elaborada por la industria farmacéutica sobre lospreparados magistrales realizados por las oficinas de farmacia, aunque éstos últimos son utilizados de manera másracional

Nanotecnología en la terapia farmacológica

Fil: Carlucci, Adriana M. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; ArgentinaFil: Bregni, Carlos. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; ArgentinaLa humanidad está frente a un momento histórico en el desarrollo de la ciencia. Muchos autores afirman que la Nanotecnología es la tecnología más importante que va a desarrollar el ser humano en los próximos años, particularmente en la medicina del futuro. Actualmente, en la Farmacoterapia ya tiene aplicaciones en los protocolos clínicos actuales, especialmente en Oncología. Su desarrollo exige que se convierta en un tema de discusión entre toda la comunidad relacionada con la salud