Connection Management Protocols for Dynamic Lightpath Provisioning in Future WDM Networks

This paper investigates and compares the performance of two GMPLS-based distributed control and management protocols for dynamic lightpath provisioning in future IP networks. The first protocol is a global information-based link state approach that consists of both an integrated RWA algorithm and a signaling algorithm. Two triggering mechanisms for the LSAs update procedures are considered; one is periodic-based and the other is threshold-based. The second protocol is a local-information based fixed alternate link routing approach where the signaling protocol is closely integrated with the RWA protocols.     

Neuron type processor modeling using a timed Petri net

The basic operation of a digital neuron is reviewed, and the theory of time Petri nets used for modeling, representation, and analysis of the neuron-type processor (NTP) is reviewed. The timed Petri net is utilized to produce a model for the digital NTP. The neuron-type processor performs input temporal and spatial summation, as well as thresholding. The timed Petri net of the NTP operates asynchronously and sequentially takes on a series of distinct internal states, so that each of these states can concurrently realize a distinct set of steering switching functions depending on the pattern of steering inputs applied to it at the time. This model is structured using several subnets, called essential module units. Depending on the desired number of input dendrites required for the NTP, the essential module units (EMU) are interconnected to produce the required timed Petri net. The timed Petri net and representation facilitates a method of analysis of neural net works containing NTPs prior to hardware implementation.     

Disaster-aware service provisioning with manycasting in cloud networks

Cloud services delivered by high-capacity optical datacenter networks are subject to disasters which may cause large-area failures, leading to huge data loss. Survivable service provisioning is crucial to minimize the effects of network/datacenter failures and maintain critical services in case of a disaster. We propose a novel disaster-aware service-provisioning scheme that multiplexes service over multiple paths destined to multiple servers/datacenters with manycasting. Our scheme maintains some bandwidth (i.e., degraded service) after a disaster failure vs. no service at all. We formulate this problem into a mathematical model which turns out to be an Integer Linear Program (ILP), and we provide heuristic optimization approaches as ILP is intractable for large problem instances. Numerical examples show that exploiting manycasting by intelligently selecting destinations in a risk-aware manner for service provisioning offers high level of survivability against link and node failures that may be caused by disasters and post-disaster failures at no extra cost compared to the other survivable schemes.     

A dynamic model for generation expansion planning

Selection of optimal size and optimal timing of addition of (new) generators are the two basic problems in generation expansion planning. In this paper we have developed a simple mathematical model for generation expansion planning which consists of an economic indicator (cost functional) and a dynamic model relating future expansion with the existing capacity and the retirement characteristics of generating units available on the market. For illustration, the proposed model has been applied to a hypothetical example of a utility and gives encouraging results.     

p53 mutation is a poor prognostic indicator for survival in patients with hepatocellular carcinoma undergoing surgical tumour ablation

Forty-two patients with hepatocellular carcinoma (HCC) were resected and their tumours were analysed for p53 mutations by GC-clamped denaturing gradient gel electrophoresis (DGGE), single-strand conformation polymorphism (SSCP) and gene sequencing. All the exons have been analysed in this study. Eight of 12 HCCs with cirrhosis due to viral hepatitis and the two patients with sarcomatoid changes displayed p53 mutations. In contrast, no mutation was observed in the fibrolamellar variant (n = 9), non-cirrhotics (n = 13) and alcoholic cirrhosis (n = 6). The mutations observed were in exons 5-8. Two mutations were observed in codons 136 and 213 as well as a T insertion between residues 156 and 157 (exon 5) and these are reported for the first time in HCC. Likewise, the silent mutation polymorphism in codon 213 was noticed in 3 of the 42 patients. Survival analysis of these patients after surgery showed the mean and median survival in patients with wild-type p53 to be 60 and 43 months respectively. In the group with p53 mutations, the mean and median survival was 15 and 12 months. The difference was statistically significant (P= 0.003).     

General model of a gas transport

A general model of transport of gases in porous membranes was established. The model was developed based on the Dusty Gas Model (DGM), solution diffusion, and surface diffusion. As a result, solutions of the model for the different transport conditions are given in this article.     

High risk of Kaposi''s sarcoma and central nervous system lymphoma in the same individuals: a finding related to acquired immunodeficiency syndrome

Kaposi's sarcoma and central nervous system (CNS) lymphoma are the 2 most common malignancies related to HIV infection. To investigate the association between Kaposi's sarcoma and CNS lymphoma, a population-based retrospective cohort study was conducted. Using U.S. Surveillance, Epidemiology and End Results Program data, the gender-specific age- and calendar year-adjusted standardized incidence ratios were calculated for the pre-AIDS (1973-80) and AIDS (1981-1990) eras, as an estimate of the relative risk (RR) of developing one condition following another. For the AIDS era in men, the RR of CNS lymphoma following Kaposi's sarcoma was 979.7 and that of Kaposi's sarcoma following CNS lymphoma was 231.1. There were no instances of the co-occurrence of these malignancies in women in either era or in men for the pre-AIDS era. The extremely high RRs for the co-occurrence of Kaposi's sarcoma and CNA lymphoma in men during the AIDS era suggests that the association of these malignancies occurs within the same HIV-infected individuals.