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IMPORTANCE: Intrahepatic cholangiocarcinoma (ICC) is a primary cancer of the liver that is increasing in incidence, and the prognostic factors associated with outcome after surgery remain poorly defined. OBJECTIVE: To combine clinicopathologic variables associated with overall survival after resection of ICC into a prediction nomogram. DESIGN, SETTING, AND PARTICIPANTS: We performed an international multicenter study of 514 patients who underwent resection for ICC at 13 major hepatobiliary centers in the United States, Europe, and Asia from May 1, 1990, through December 31, 2011. Multivariate Cox proportional hazards regression modeling with backward selection using the Akaike information criteria was used to select variables for construction of the nomogram. Discrimination and calibration were performed using Kaplan-Meier curves and calibration plots. INTERVENTIONS: Surgical resection of ICC at a participating hospital. MAIN OUTCOMES AND MEASURES: Long-term survival, effect of potential prognostic factors, and performance of proposed nomogram. RESULTS: Median patient age was 59.2 years, and 53.1% of the patients were male. Most patients (74.7%) had a solitary tumor, and median tumor size was 6.0 cm. Patients were treated with an extended hepatectomy (202 [39.3%]), a hemihepatectomy (180 [35.0%]), or a minor liver resection (<3 segments) (132 [25.7%]). Most patients underwent R0 resection (87.9%), and 35.7% of patients had N1 disease. Using the backward selection of clinically relevant variables, we found that age at diagnosis (hazard ratio [HR], 1.31; P < .001), tumor size (HR, 1.50; P < .001), multiple tumors (HR, 1.58; P < .001), cirrhosis (HR, 1.51; P = .08), lymph node metastasis (HR, 1.78; P = .01), and macrovascular invasion (HR, 2.10; P < .001) were selected as factors predictive of survival. On the basis of these factors, a nomogram was created to predict survival of ICC after resection. Discrimination using Kaplan-Meier curves, calibration curves, and boot

Feng, Shen., Thesis (M.Phil.)--Chinese University of Hong Kong, 2013., Includes bibliographical references (leaves 84-88)., Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web., s also in Chinese., http://library.cuhk.edu.hk/record=b5884539, Use of this resource is governed by the terms and conditions of the Creative Commons “Attribution-NonCommercial-NoDerivatives 4.0 International” License (http://creativecommons.org/licenses/by-nc-nd/4.0/)

Feng, Shen., Thesis (M.Phil.)--Chinese University of Hong Kong, 2013., Includes bibliographical references (leaves 84-88)., Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web., s also in Chinese., http://library.cuhk.edu.hk/record=b5884539, Use of this resource is governed by the terms and conditions of the Creative Commons “Attribution-NonCommercial-NoDerivatives 4.0 International” License (http://creativecommons.org/licenses/by-nc-nd/4.0/)

This work investigates the maximum broadcast throughput and its achievability in multi-hop wireless networks with half-duplex node constraint. We allow the use of physical-layer network coding (PNC). Although the use of PNC for unicast has been extensively studied, there has been little prior work on PNC for broadcast. Our specific results are as follows: 1) For single-source broadcast, the theoretical throughput upper bound is n/(n+1), where n is the "min vertex-cut" size of the network. 2) In general, the throughput upper bound is not always achievable. 3) For grid and many other networks, the throughput upper bound n/(n+1) is achievable. Our work can be considered as an attempt to understand the relationship between max-flow and min-cut in half-duplex broadcast networks with cycles (there has been prior work on networks with cycles, but not half-duplex broadcast networks)., Comment: 23 pages, 18 figures, 6 tables

Traditional wireless sensor networks (WSNs) working in the license-free spectrum suffer from uncontrolled interference as the license-free spectrum becomes increasingly crowded. Designing a WSN based on cognitive radio can be promising in the near future in order to provide data transmissions with quality of service requirements. In this thesis, we introduce a cognitive radio sensor network (CRSN) and analyze its performance for supporting real-time traffic. The network devices opportunistically access vacant (or available) channels in the licensed spectrum. When the current channel becomes unavailable, the devices can switch to a new channel. Three types of real-time traffic are considered, constant-bit-rate (CBR) traffic, bursty traffic, and Poisson traffic. For the CBR traffic, a fixed number of packets are generated periodically; for the bursty traffic, a burst of packets are generated periodically and the number of packets in each burst is random; and for the Poisson traffic, the packet arrivals follow Poisson process. We derive the average packet transmission delay for each type of the traffic. The analytical results are verified by computer simulations. Our results indicate that real-time traffic can be effectively supported in the CRSN, and packets with the Poisson arrivals may experience longer average delay than the bursty arrivals., Master of Applied Science (MASc)

Based on the Raytheon model, GaAs E/D HEMT model parameters are measured and their statistical deviations and correlation coefficients are determined. Output current deviations of transistor current sources and DC offset voltages of differential amplifiers, which represent basic limitations of precise data conversion ICs, are characterized using these experimental data and derived equations with seven model parameters. Monte-carlo simulations are carried out on an 8 bit D/A converter and a latched comparator, which were implemented in 0.5 ?m GaAs E/D HEMT technology, and simulated results are shown to be identical to measured accuracies of these two circuits.

Based on the Raytheon model, GaAs E/D HEMT model parameters are measured and their statistical deviations and correlation coefficients are determined. Output current deviations of transistor current sources and DC offset voltages of differential amplifiers, which represent basic limitations of precise data conversion ICs, are characterized using these experimental data and derived equations with seven model parameters. Monte-carlo simulations are carried out on an 8 bit D/A converter and a latched comparator, which were implemented in 0.5 ?m GaAs E/D HEMT technology, and simulated results are shown to be identical to measured accuracies of these two circuits.