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To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.ejor.2006.04.036 Byline: Suresh K. Nair (a), David C. Novak (b) Keywords: Markov decision process; Traffic shaping; Bandwidth; Goal programming Abstract: The management of technology in multi-service computer networks, such as university networks, has become a challenge with the explosive growth of entertainment oriented peer-to-peer (P2P) traffic. Traffic shaping is one of the tools used to manage bandwidth to improve system performance by allocating bandwidth between P2P and non-peer-to-peer (NP2P) traffic. We present a model for traffic shaping and bandwidth management that considers the trade-offs from allocating different amounts of bandwidths for different application categories and use data from a university network. The current policy allocates varying bandwidths over the day to P2P and NP2P traffic to reflect the importance of not letting entertainment based traffic choke the network during the day time at the expense of the more important traffic, such as Web traffic. We highlight the difficulties in obtaining data in the form required for analysis, and the need to estimate demand for allocations not covered by current policy. We present a goal programming model for this estimation task. We also model the traffic shaping problem as a Markov decision process and develop an algorithm for determining the optimal bandwidth allocation to maximize the utility of all users. Finally we use a numerical example to illustrate our approach. Author Affiliation: (a) Department of Operations and Information Management, School of Business Administration, 2100 Hillside Road, Unit 1041 OPIM, University of Connecticut, Storrs, CT 06269-1041, United States (b) School of Business Administration, 310 Kalkin Hall, 55 Colchester Ave., University of Vermont, Burlington, VT 05405-0157, United States Article History: Received 22 December 2004; Accepted 27 April 2006

This paper is a critical engagement with Freud's anthropological theory of the origins of law and religion, which Freud developed as his representation and development of the Oedipal myth. Freud's mythology, it is argued, is the theoretical result of the essentially narrative nature of psychoanalytical praxis. Freud's myth, especially its treatment of patricide as the original sin, is seen to be a displacement of the biblical myth of fratricide as the original sin. It is argued that the biblical myth is more coherent than Freud's myth, and that it corresponds to the reality of the human condition better than Freud's myth. The paper concludes with the suggestion that the acceptance of the biblical myth in place of Freud's does not necessarily entail a rejection of psychoanalysis as a praxis. [ABSTRACT FROM AUTHOR]

In this paper we examine the outcomes associated with an innovative change in a state-level transportation project prioritization process within the United States (U.S.). A foundational component of the innovation is the development and implementation of a novel multi-criteria analysis (MCA) tool to aid decision-makers. The pre and post-MCA project prioritization processes are described in detail for the state of Vermont, and we use a mixed methodological approach to empirically evaluate the outcomes associated with the innovative change with respect to three objectives: (1) to make the project prioritization process more transparent, (2) to improve the project prioritization process by incorporating well-defined, objective evaluation criteria into the decision-making process, and (3) to reduce inequality in the allocation of transportation project funds between the local jurisdictions. We demonstrate that the innovative change in the project prioritization process was clearly successful in accomplishing objectives 1 and 2, but does not appear to be successful with respect to accomplishing objective 3. The findings are discussed in the context of the state of Vermont, and we offer suggestions for how funding inequality might be addressed in the future. [ABSTRACT FROM AUTHOR]

Abstract: The evaluation and subsequent ranking of transportation roadway projects has traditionally been based on localized performance criteria that do not consider how individual projects may impact the network as a whole. A novel approach for prioritizing projects using a spatially sensitive, network-based performance metric called The Network Trip Robustness (NTR) is demonstrated in this paper. The NTR incorporates spatial aspects of network topology, network connectivity, and the dynamic rerouting of traffic on roadway links into the prioritization process. The approach is illustrated in practice using the actual road network, travel demand data, and roadway projects from the Chittenden County Regional Planning Commission (CCRPC) of Vermont. Results are discussed in the context of which projects provide the greatest expected travel time benefits for the network as a whole. Implementing more projects does not necessarily result in additional benefits, and the benefits associated with individual projects cannot simply be extrapolated across groups of projects in an additive manner. The evaluation of project groups appears to require a permutation-based approach where sequencing is critically important. The results can be generalized to other road networks and illustrate the spatially complex characteristics of transportation networks and some of the difficulties these characteristics create with respect to prioritizing roadway projects. [Copyright &y& Elsevier]

Abstract: Metric space is a universal and versatile model of similarity that can be applied in various areas of information retrieval. However, a general, efficient, and scalable solution for metric data management is still a resisting research challenge. We introduce a novel indexing and searching mechanism called Metric Index (M-Index) that employs practically all known principles of metric space partitioning, pruning, and filtering, thus reaching high search performance while having constant building costs per object. The heart of the M-Index is a general mapping mechanism that enables to actually store the data in established structures such as the B+-tree or even in a distributed storage. We implemented the M-Index with the B+-tree and performed experiments on two datasets—the first is an artificial set of vectors and the other is a real-life dataset composed of a combination of five MPEG-7 visual descriptors extracted from a database of up to several million digital images. The experiments put several M-Index variants under test and compare them with established techniques for both precise and approximate similarity search. The trials show that the M-Index outperforms the others in terms of efficiency of search-space pruning, I/O costs, and response times for precise similarity queries. Further, the M-Index demonstrates excellent ability to keep similar data close in the index which makes its approximation algorithm very efficient—maintaining practically constant response times while preserving a very high recall as the dataset grows and even beating approaches designed purely for approximate search. [Copyright &y& Elsevier]

Abstract: The blocking probability is commonly used to evaluate the quality-of-service (QoS) offered by dialup Internet Service Providers (ISPs). Unfortunately, dialup ISPs employ no blocking standards or thresholds. This raises questions as to exactly how providers measure and evaluate QoS with respect to network access and how they make capacity planning decisions. Many ISPs use the User-to-Modem Ratio (UMR) as a surrogate measure for service quality, but there are no well defined direct relationships between the UMR and the blocking probability. In this paper, relationships between the UMR and other well known traffic variables and the blocking probability are quantified, and the usefulness of the UMR as a standalone QoS metric is explored. Blocking probabilities are estimated for a range of UMRs via simulation from a range of demand scenarios developed from observed data. A predictive regression model is introduced to quantify the affects of independent predictor variables on blocking. Results show that the UMR is not a useful standalone QoS metric and traditionally favored UMRs such as 10:1 cannot be associated with “high quality service” in a de facto manner. [Copyright &y& Elsevier]

Abstract: Highway planning efforts, especially those involving capacity expansions, have traditionally relied on the volume/capacity (V/C) ratio to identify “highly congested” or critical links, resulting in localized solutions that do not consider system-wide impacts. This paper presents a new, comprehensive, system-wide approach to identifying critical links and evaluating network performance. The approach considers network flows, link capacity and network topology. Moreover, it relies on readily available sources of data. Using three hypothetical networks, we demonstrate that the approach, known as the Network Robustness Index, yields different highway planning solutions than the traditional V/C ratio. Moreover, these solutions yield far greater system-wide benefits, as measured by travel-time savings, than solutions identified by the V/C ratio. [Copyright &y& Elsevier]

• Introduces a novel iterative heuristic for clustering, allocation and routing of snow and ice control vehicles. • Heuristic addresses important real-world operational constraints. • Heuristic incorporates a continuous measure of link criticality within the allocation step. • The link-criticality measure is shown to improve the time it takes to service the most critical links in an application to the state of Vermont's roadway network. • The application also shows that advanced vehicle-allocation methods can be more effective at improving snow and ice control service than adding trucks to the fleet. Many states in the U.S. have experienced increased demand for roadway snow and ice control (RSIC) operations due to an increase in extreme winter weather. As the number and severity of extreme weather events increases, the costs associated with winter roadway maintenance materials, plow operator time, equipment maintenance and replacement, and fuel use will also increase. In this paper, we introduce a unique heuristic procedure which we combine with real-world operational constraints to advance both the modeling and practical application of RSIC operations by incorporating a continuous measure of priority into a sequenced, iterative heuristic for network clustering, vehicle allocation, and capacitated vehicle routing. The heuristic balances the competing objectives of minimizing the total vehicle hours traveled for the fleet and minimizing the total time required to service the most critical links in the roadway network, while ensuring that the entire fleet is put to use. We also introduce a new measure of route-system performance, which is based on an effective link length (adjusted for how critical the link is to the performance of the entire system) and the time it takes to service the most critical links. We demonstrate the approach in practice by running five different applications of the heuristic on the statewide roadway network in Vermont. We demonstrate conclusively that our heuristic is effective for servicing the most critical links in the network in the least amount of time. We show that our more advanced vehicle allocation methods result in more effective RSIC service operations than adding vehicles to the fleet. [ABSTRACT FROM AUTHOR]

Proteins are subject to oxidative modification and the formation of adducts with a broad spectrum of reactive species via enzymatic and non-enzymatic mechanisms. Here we report that in vitro non-enzymatic methylglyoxal (MGO) binding causes the inhibition and formation of MGO advanced glycation end-products (MAGEs) in Na + /K + -ATPase (NKA). Concretely, MGO adducts with NKA amino acid residues (mainly Arg) and N ε -(carboxymethyl)lysine (CML) formation were found. MGO is not only an inhibitor for solubilized NKA (IC 50 =91±16 μM), but also for reconstituted NKA in the lipid bilayer environment, which was clearly demonstrated using a DPPC/DPPE liposome model in the presence or absence of the NKA-selective inhibitor ouabain. High-resolution mass spectrometric analysis of a tryptic digest of NKA isolated from pig ( Sus scrofa ) kidney indicates that the intracellular α-subunit is naturally (post-translationally) modified by MGO in vivo . In contrast to this, the β-subunit could only be modified by MGO artificially, and the transmembrane part of the protein did not undergo MGO binding under the experimental setup used. As with bovine serum albumin, serving as the water-soluble model, we also demonstrated a high binding capacity of MGO to water-poorly soluble NKA using a multi-spectral methodology based on electroanalytical, immunochemical and fluorimetric tools. In addition, a partial suppression of the MGO-mediated inhibitory effect could be observed in the presence of aminoguanidine (pimagedine), a glycation suppressor and MGO-scavenger. All the results here were obtained with the X-ray structure of NKA in the E1 conformation (3WGV) and could be used in the further interpretation of the functionality of this key enzyme in the presence of highly-reactive metabolic side-products, glycation agents and generally under oxidative stress conditions. [ABSTRACT FROM AUTHOR]

Abstract: Checkpoint kinase 2 (CHEK2) is a protein involved in arresting cell cycle in response to DNA damage. To investigate whether it plays an important role in the development of prostate cancer (PRCA) in the Ashkenazi Jewish (AJ) population, we sequenced CHEK2 in 75 AJ individuals with prostate, breast, or no cancer (n =25 each). We identified seven coding SNPs (five are novel) that changed the amino-acid sequence, resulting in R3W, E394F, Y424H, S428F, D438Y, P509S, and P509L. We determined the frequency of each variant in 76 AJ families collected by members of the International Consortium for Prostate Cancer Genetics (ICPCG) where ⩾2 men were affected by PRCA. Only one variant, Y424H in exon 11, was identified in more than two families. Exon 11 was then screened in nine additional AJ ICPCG families (a total of 85 families). The Y424H variant occurred in nine affected cases from four different families; however, it did not completely segregate with the disease. We performed bioinformatics analysis, which showed that Y424H is a non-conservative missense substitution that falls at a position that is invariant in vertebrate CHEK2 orthologs. Both SIFT and Align-GVGD predict that Y424H is a loss of function mutation. However, the frequency of Y424H was not significantly different between unselected AJ cases from Montreal/Memorial Sloan Kettering Cancer Centre (MSKCC) and AJ controls from Israel/MSKCC (OR 1.18, 95%CI: 0.34–4.61, p =.99). Moreover, functional assays using Saccharomyces cerevisiae revealed that the Y424H substitution did not alter function of CHEK2 protein. Although we cannot rule out a subtle influence of the CHEK2 variants on PRCA risk, these results suggest that germline CHEK2 mutations have a minor role in, if any, PRCA susceptibility in AJ men. [Copyright &y& Elsevier]