Role of dispersion in pulse emission from a sliding-frequency fiber laser

6openopenRomagnoli, M.; Wabnitz, Stefan; Franco, P.; Midrio, M.; Bossalini, L.; Fontana, F.M., Romagnoli; Wabnitz, Stefan; P., Franco; M., Midrio; L., Bossalini; F., Fontan

Chirp management in silicon-graphene electro absorption modulators

We study the frequency chirp properties of graphene-on-silicon electro-absorption modulators (EAMs). By experimentally measuring the chirp of a 100 \ub5m long single layer graphene EAM, we show that the optoelectronic properties of graphene induce a large positive linear chirp on the optical signal generated by the modulator, giving rise to a maximum shift of the instantaneous frequency up to 1.8 GHz. We exploit this peculiar feature for chromatic-dispersion compensation in fiber optic transmission thanks to the pulse temporal lensing effect. In particular, we show dispersion compensation in a 10Gb/s transmission experiment on standard single mode fiber with temporal focusing distance (0-dB optical-signal-to-noise ratio penalty) of 60 km, and also demonstrate 100 km transmission with a bit error rate largely lower than the conventional Reed-Solomon forward error correction threshold of 10 123

European consensus meeting of ARM-Net members concerning diagnosis and early management of newborns with anorectal malformations.

The ARM-Net (anorectal malformation network) consortium held a consensus meeting in which the classification of ARM and preoperative workup were evaluated with the aim of improving monitoring of treatment and outcome. The Krickenbeck classification of ARM and preoperative workup suggested by Levitt and Peña, used as a template, were discussed, and a collaborative consensus was achieved. The Krickenbeck classification is appropriate in describing ARM for clinical use. The preoperative workup was slightly modified. In males with a visible fistula, no cross-table lateral X-ray is needed and an anoplasty or (mini-) posterior sagittal anorectoplasty can directly be performed. In females with a small vestibular fistula (Hegar size 5 mm, and in the meantime, gentle painless dilatations can be performed. In both male and female perineal fistula and either a low birth weight (<2,000 g) or severe associated congenital anomalies, prolonged preoperative painless dilatations might be indicated to decrease perioperative morbidity caused by general anesthesia. The Krickenbeck classification is appropriate in describing ARM for clinical use. Some minor modifications to the preoperative workup by Levitt and Peña have been introduced in order to refine terminology and establish a comprehensive preoperative workup

Inter- and Intraobserver Variation in the Assessment of Preoperative Colostograms in Male Anorectal Malformations: An ARM-Net Consortium Survey

Aim: Male patients with anorectal malformations (ARM) are classified according to presence and level of the recto-urinary fistula. This is traditionally established by a preoperative high-pressure distal colostogram that may be variably interpreted by different surgeons. The aim of this study was to evaluate the inter- and intraobserver variation in the assessment by pediatric surgeons of preoperative colostograms with respect to the level of the recto-urinary fistula. Materials and Methods: Sixteen pediatric surgeons from 14 European centers belonging to the ARM-Net Consortium twice scored 130 images of distal colostograms taken in sagittal projection at a median age of 66 days of life (range: 4–1,106 days). Surgeons were asked to classify the fistula in bulbar, prostatic, bladder-neck, no fistula, and “unclear anatomy” example. Their assessments were compared with the intraoperative findings (kappa) for two scoring rounds with an interval of 6 months (intraobserver variation). Agreement among the surgeons' scores (interobserver variation) was also calculated using Krippendorff's alpha. A kappa over 0.75 is considered excellent, between 0.40 and 0.75 fair to good, and below 0.40 poor. Surgeons were asked to score the images in “poor” and “good” quality and to provide their years of experience in ARM treatment. Results: Agreement between the image-based rating of surgeons and the intraoperative findings ranges from 0.06 to 0.45 (mean 0.31). Interobserver variation is higher (Krippendorff's alpha between 0.40 and 0.45). Years of experience in ARM treatment does not seem to influence the scoring. The mean intraobserver variation between the two rounds is 0.64. Overall, the quality of the images is considered poor. Images categorized as having a good quality result in a statistically significant higher kappa (mean: 0.36 and 0.37 in the first and second round, respectively) than in the group of bad-quality images (mean: 0.25 and 0.23, respectively). Conclusions: There is poor agreement among experienced pediatric colorectal surgeons on preoperative colostograms. Techniques and analyses of images need to be improved in order to generate a homogeneou

Transitional Care for Patients with Congenital Colorectal Diseases: An EUPSA Network Office, ERNICA, and eUROGEN Joint Venture

Background: Transition of care (TOC; from childhood into adulthood) of patients with anorectal malformations (ARM) and Hirschsprung disease (HD) ensures continuation of care for these patients. The aim of this international study was to assess the current status of TOC and adult care (AC) programs for patients with ARM and HD. Methods: A survey was developed by members of EUPSA, ERN eUROGEN, and ERNICA, including patient representatives (ePAGs), comprising of four domains: general information, general questions about transition to adulthood, and disease-specific questions regarding TOC and AC programs. Recruitment of centres was done by the ERNs and EUPSA, using mailing lists and social media accounts. Only descriptive statistics were reported. Results: In total, 82 centres from 21 different countries entered the survey. Approximately half of them were ERN network members. Seventy-two centres (87.8%) had a self-reported area of expertise for both ARM and HD. Specific TOC programs were installed in 44% of the centres and AC programs in 31% of these centres. When comparing centres, wide variation was observed in the content of the programs. Conclusion: Despite the awareness of the importance of TOC and AC programs, these programs were installed in less than 50% of the participating centres. Various transition and AC programs were applied, with considerable heterogeneity in implementation, content and responsible caregivers involved. Sharing best practice examples and taking into account local and National Health Care Programs might lead to a better continuation of care in the future. Level of Evidence: III