Si3N4-plasmonic ferroelectric MZIR modulator for 112-Gbaud PAM-4 transmission in the O-band.

This paper presents a simulation-based analysis on the performance of plasmonic ferroelectric Mach-Zehnder in a ring (MZIR) versus symmetric Mach-Zehnder modulators (MZMs) on Si3N4 targeting O-band operation. The detailed investigation reveals the tradeoff between Au and Ag legacy noble metals providing lower modulator losses and CMOS compatible Cu featuring low cost. The numerical models also show that by opting for the MZIR layout there is a reduction in the Vπ x L product of 46% for Ag, 39% for Au and 30% for Cu versus MZMs. Time-domain simulations verify the successful generation of 112 Gbaud PAM-4 Signals from both MZIRs and MZMs for as low as 2 × 1.3 Vpp and 5µm long plasmonic phase shifters (PSs) with MZIRs providing a ΔQ signal improvement over MZMs of 2.9, 2.4, and 1.3 for Ag, Au, and Cu metals respectively. To the best of our knowledge, this is the first theoretical demonstration of such a low-loss, low-voltage, high-speed, and CMOS compatible plasmonic modulator on Si3N4, in the O-band.

Intensive care unit outcomes following orthotopic liver transplantation: single-center experience and review of the literature.

BACKGROUND/AIM: Orthotopic Liver Transplantation (OLT) is the treatment of choice for patients with end stage liver disease, acute liver failure, hepatocellular carcinoma and metabolic disorders. As a result of improvement in surgical and anesthesiological skills, advanced understanding of transplant immunology and better critical care management of complications, patients survive longer after liver transplantation. It has been gradually achieved one-year survival rates of 80-90%. During the early post-operative period, all patients undergoing OLT are admitted to the intensive care unit, as they need a management of both preexisting patient's conditions and post-operative complications, usually due to either adverse intra-operative or post-operative events. The purpose of this review is the detailed recording, understanding and interpretation of immediate post-operative complications occurred in patients undergoing OLT, in intensive care unit. This could help to improve patient's treatment and reduce the incidence of complications, with further reduction of morbidity-mortality and cost. We also present our experience from the first 32 OLT patients from Liver Transplantation Unit of Laiko General Hospital, the only Liver Transplantation Unit in Athens. MATERIALS AND METHODS: This literature review was performed using the MEDLINE database. The key words were; Orthotopic liver transplantation; intensive care unit; post-operative complications; outcomes. One hundred-sixteen articles published in English until 2018 were used. We also use all the results from our 32 patients from our Liver Transplantation Unit during the period 07/2006 to 07/2009. RESULTS: All patients undergoing OLT admitted to the intensive care unit for a period of time, depending on the occurrence of post-operative complications. The incidence of primary failure ranges between 2-14%, whereas post-operative bleeding ranges between 7-15%. The treatment is usually conservative, although surgical repair may need in 10-15%. Acute renal failure post-operative is not an infrequent problem too, and has been reported to occur in 9% to 78% of cases. Acute rejection normally occurs 7-14 days after OLT. Additionally, the delay of the weaning from mechanical ventilation in the immediate post-operative period could increase the complications. Infectious complications are quite common almost from the first post-operative day in intensive care unit. CONCLUSIONS: Prolonged intensive care stay could increase the complications post-operative Infectious complications, renal and respiratory impairment are among the most common causes of early post-transplant morbidity and mortality.

Wire localisation biopsy of non-palpable breast lesions: reasons for unsuccessful excision.

Surgical excision following needle-wire localization of nonpalpable, mammographically detected breast lesions is a very valuable diagnostic and therapeutic procedure. No further treatment is usually required after establishing an accurate histological benign diagnosis of indeterminate lesions on preoperative assessment. On the other hand, ductal carcinoma in-situ (DCIS) and early invasive cancer, properly excised, may sometimes require further management depending on specific histologic findings. An uncommon problem of this procedure is the failure to identify, localize or excise the breast lesion. In this review article, factors that contribute to the failed needle localization procedure are presented.