161 research outputs found
Semiconductor Optical Amplifier (SOA)–Based Amplification of Intensity-Modulated Optical Pulses — Deterministic Timing Jitter and Pulse Peak Power Equalization Analysis
During the last few years, large-scale efforts towards realizing high-photonic integration densities have put SOAs in the spotlight once again. Hence, the need to develop a complete framework for SOA-induced signal distortion to accurately evaluate a system’s performance has now become evident. To cope with this demand, we present a detailed theoretical and experimental investigation of the deterministic timing jitter and the pulse peak power equalization of SOA-amplified intensity-modulated optical pulses. The deterministic timing jitter model relies on the pulse mean arrival time estimation and its analytic formula reveals an approximate linear relationship between the deterministic timing jitter and the logarithmic values of intensity modulation when the SOA gain recovery time is faster than the pulse period. The theoretical analysis also arrives at an analytic expression for the intensity modulation reduction (IMR), which clearly elucidates the pulse peak power equalization mechanism of SOA. The IMR analysis shows that the output intensity modulation depth is linearly related to the respective input modulation depth of the optical pulses when the gain recovery time is faster than the pulse period. This novel theoretical platform provides a qualitative and quantitative insight into the SOA performance in case of intensity-modulated optical pulses
Relayed-QKD and switched-QKD networks performance comparison considering physical layer QKD limitations
We experimentally evaluate the SKR generation for unoptimized QKD pairs in
switched QKD and compare the performance of the switched-QKD with relayed-QKD
networks to reveal they perform better for short distances and at large
networks.Comment: 3 page
An Exploratory Study on the Northern Sea Route as an Alternative Shipping Passage
This qualitative inductive research explores the potential benefits for the Scandinavian economy and ports through the implementation of the Northern Sea Route (NSR) as an alternative for container shipping to the established Southern route through the Suez Canal. To extract expert’s opinions and address these objectives, we utilised in-depth face-to-face semi-structured interviews through purposive sampling in a single case study setting.
The analysis of the data demonstrates that the commercialisation of NSR can yield benefits for the Scandinavian economy (e.g. GDP increase, jobs creation) and reveals the benefits of Scandinavian ports (e.g. ECA’s, flexibility, hinterland, etc.) compared to other ports in North West Europe, which potentially grasp the NSR as an opportunity. However, it is highlighted that this can only be achieved if Scandinavian countries are proactive and secure their involvement
Modelling of micro-sources for security studies
International audienceThe interconnection of small, modular generation and storage technologies at the MV and LV distribution level have the potential to significantly impact power system performance. In this paper models of the main micro-generation sources are described. In particular, the models of Microturbines, Fuel Cells, Photovoltaic Systems and Wind Turbines, are described. In addition basic models of their power electronic interfaces are given. The integration of the above models in a steady state and dynamic simulation tool, which is developed in the framework of the EU funded MICROGRIDS project, will provide a simulation test platform, which will be necessary to define and evaluate the developed operational and control strategies
O-band QKD link over a multiple ONT loaded carrier-grade GPON for FTTH applications
We have successfully integrated an O-band commercial Quantum-Key-Distribution
(QKD) system over a lit GPON testbed that replicates a carrier-grade
Fiber-to-the-Home (FTTH) optical access network with multiple ONTs to emulate
real-life FTTH operational deployments.Comment: 3 page
Endoscopic application of n-butyl-2-cyanoacrylate on esophagojejunal anastomotic leak: a case report
<p>Abstract</p> <p>Introduction</p> <p>This case report describes an esophagojejunal anastomotic leak following total gastrectomy for gastric cancer. The leak was treated successfully with endoscopic application of <it>n</it>-butyl-2-cyanoacrylate. This is the first case report on the endoscopic application of cyanoacrylate alone for the treatment of an anastomotic leak.</p> <p>Case presentation</p> <p>This report describes a case of a 68-year-old Caucasian man who underwent surgery for gastric cancer. He underwent total gastrectomy and esophagojejunal anastomosis with Roux-en-Y anastomosis plus transverse colectomy. An anastomotic leak was treated conservatively at first for a total of three weeks. However, the leak persisted; therefore, the decision was made to apply topical endoscopic <it>n</it>-butyl-2-cyanoacrylate.</p> <p>Conclusion</p> <p>The endoscopic application of <it>n</it>-butyl-2-cyanoacrylate alone can be used successfully to treat esophagojejunal anastomotic leakage.</p
Molecular detection (k-ras) of exfoliated tumour cells in the pelvis is a prognostic factor after resection of rectal cancer?
<p>Abstract</p> <p>Background</p> <p>After total mesorectal excision (TME) for rectal cancer around 10% of patients develops local recurrences within the pelvis. One reason for recurrence might be spillage of cancer cells during surgery. This pilot study was conducted to investigate the incidence of remnant cancer cells in pelvic lavage after resection of rectal cancer. DNA from cells obtained by lavage, were analysed by denaturing capillary electrophoresis with respect to mutations in hotspots of the <it>k-ras </it>gene, which are frequently mutated in colorectal cancer.</p> <p>Results</p> <p>Of the 237 rectal cancer patients analyzed, 19 had positive lavage fluid. There was a significant survival difference (p = 0.006) between patients with <it>k-ras </it>positive and negative lavage fluid.</p> <p>Conclusion</p> <p>Patients with <it>k-ras </it>mutated cells in the lavage immediately after surgery have a reduced life expectation. Detection of exfoliated cells in the abdominal cavity may be a useful diagnostic tool to improve the staging and eventually characterize patients who may benefit from aggressive multimodal treatment of rectal cancer.</p
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