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The paper introduces first the key drivers of the present evolution of the electric system and shows how the network is the key element to integrate an increasing amount of renewable generation. Then, the smart grids philosophy is introduced: this concept, initially specifically associated to distribution systems, is more and more related to the transmission grid too. Depending on different factors, transmission grid investments may also address distribution grid issues and be more generally beneficial for the system. The transmission system itself has also to evolve to handle new challenges in a situation in which authorization for new lines is becoming increasingly difficult. Hence, important opportunities are offered by the new transmission technologies. The paper presents a review of the most important of them, showing their degree of maturity. The results shown here are based on some activities of the European FP7 project REALISEGRID (http://realisegrid.rse-web.itrealisegrid.rse-web.it).

Background: Granulosa-cells are able to produce and store leptin, suggesting that this hormone is locally involved in the regulation of follicular growth. In this study, the role of follicular fluid (FF) leptin concentration in predicting oocyte fertilization and embryo quality was evaluated in 35 normogonadotrophic women undergoing controlled ovarian stimulation (COS) for assisted reproductive techniques. Materials and Methods: Leptin concentration was measured in 47 consecutively collected FF in which a mature oocyte had been found during the ovum pick-up. Embryos deriving from fertilized oocytes were submitted to quality scoring systems. Results: Mean leptin concentration was significantly higher in FF whose oocytes showed 2 pronuclei (no. 25) when compared with those with no evidence of fertilization (no. 22) at the 16–18 h check (26.0±6.1 vs 15.3±10.6 ng/ml, respectively, p<0.01). Follicular mean diameters were similar in the two groups (21.4±3.4 and 21.0±5.1 mm, respectively). Logistic regression analysis identified FF leptin levels as the best predictive parameter for oocyte fertilization (p<0.001). When receiving operating characteristics curve was employed, a FF leptin concentration of 20.25 ng/ml was the most reliable cut-off in predicting fertilization of oocytes. FF with leptin concentrations higher than this value (no. 27) had an oocyte fertilization rate of 85.7%. In contrast, FF levels ≤20.25 ng/ml (no. 20) were associated with a rate of 16.7% (p<0.05). No correlation emerged between FF leptin and the score attributed to 15 valuable embryos at the zygote stage (r=−0.01) and at 48 h after insemination (r=0.1). Conclusions: FF leptin levels are a better predictor of oocyte fertilization success rates than follicular diameter. These results underline the relevance of FF variables in developing methods for oocyte selection.

In our quest toward the discovery of highly potent and acid-stable motilides, novel 4‘‘-deoxy derivatives of 9-deoxo-6,9-epoxyerythromycin were designed, synthesized, and evaluated for their gastrointestinal prokinetic activities. These compounds, in their 9R configuration, were more potent than their 6,9-enol ether homologues in inducing well-coordinated smooth muscle contractions in an in vitro rabbit duodenal assay:  e.g., (9R),(8S)-9-deoxo-4‘‘-deoxy-3‘-N-desmethyl-3‘-N-ethyl-6,9-epoxyerythromycin A (10) and (9R),(8S)-9-deoxo-4‘‘-deoxy-3‘-N-desmethyl-3‘-N-ethanol-6,9-epoxyerythromycin A (15) had a pED50 of 8.54 and 8.11 compared to a pED50 of 7.22 for compound 2 (ABT-229). Reduction of the 6,9-enol ether, which was aimed at improving the acid stability, afforded the most stable motilides to date with t1/2 of 5.5 h for 10 and 15. Compounds 10 and 15 bind specifically to rabbit antral smooth muscle motilin receptors with pIC50 values of 8.52 and 8.70.

This paper describes some observations of pulsed laser damage to optical fibers with emphasis on a damage mode characterized as a linear fracture along the outer core of a fiber. Damage threshold data are presented which illustrate the effects of the focusing lens, end-surface preparation, and type of fiber. An explanation based on fiber-beam misalignment is given and is illustrated by a simple experiment and ray trace.