Abstract-We experimentally investigate a dispersion-managed four-channel 2R regenerator that relies on self-phase modulationinduced spectral broadening and offset filtering at four shifted wavelengths. The device consists of several alternating sections of dispersion-compensating fibers and single-mode fibers. Due to this arrangement and the use of low duty-cycle return-to-zero pulses, nonlinear interchannel effects are sufficiently mitigated resulting in almost no additional degradation compared to the single-channel case.

Single-channel 2R regeneration has been widely demonstrated in the past using highly nonlinear fiber (HNLF)-based regenerators that exploit the self-phase modulation (SPM) effect. However, the direct extension of these regenerators to include multi-wavelength (multi-X) operation is not feasible due to the debilitating nonlinear interaction between the WDM channels, associated with the cross-phase modulation effect (XPM). In the present paper two appropriately modified fiber-based schemes for multi-4 regeneration at 40 Gb/s and even higher data rate are presented. The schemes utilize multiple fibers with alternating dispersion, minimizing the effect of XPM and resulting in regeneration of the degraded WDM channels. INTRODUCTIONAs wavelength division multiplexing (WDM) becomes the natural choice for all kinds of optical networks, the extension of today's single-channel 2R regeneration schemes to multi-4 operation is considered as a strategic goal for making optical networking a powerful and economically viable solution. It is a widely-held opinion that the development of multi-4 regenerators has the potential to follow the paradigm of optical amplification and its application in WDM systems, introducing another major revolution in optical communications. The significance of the targeted multi-4 operation is associated with the ability to handle a number of channels using a single element rather than having to demultiplex the individual channels and apply regeneration discretely to each one of them. Fiber-based subsystems are considered as excellent candidates for the realization of such elements, having the additional potential of efficient operation at high bit rates, since the nonlinearity for the regenerative functionality originates in their case from the Kerr effect, and thus it can be considered practically instantaneous.

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This paper examines the emergence of innovative Present Perfect structures in the Cypriot Greek koiné through a quantitative study supplemented by naturalistically sampled data. The results of the study indicate that innovative Present Perfect structures are emergent in contemporary Cypriot Greek, at least among its younger, more educated speakers. Although such innovation on the morphosyntactic level may well be a result of language contact with Standard Greek, it does not entail perfect acquisition or transfer of the full range of associated semantic features of Standard Greek Present Perfect. Conversely, it seems that transfer of the exclusively resultative semantics of extant, non-innovative Cypriot Greek Present Perfect structures onto the innovative Present Perfect is not operative either.

The present paper is a contribution to the study of a new Modern Greek variety that is spoken in Canada by first-generation immigrants who arrived in this country between 1945 and 1975. This variety displays features originating from: (a) A Common Modern Greek spoken in Greece around the middle of the 20th century, (b) mutually intelligible characteristics of the immigrants’ native dialectal varieties, mainly from the Peloponnese, (c) contact with English, (d) Standard Modern Greek. We present, discuss, and analyze data collected within the framework of the project “ImmiGrec: Stories of Greek immigration in Canada.” We focus on linguistic elements that could be considered indicative features of a Greek-Canadian Koiné, more particularly by investigating the borrowing and integration of English nouns and the variation in the use of the unstressed syllabic augment /e-/ and two different imperfective past suffixes.