111 research outputs found

    The Price of Anarchy in Transportation Networks: Efficiency and Optimality Control

    Full text link
    Uncoordinated individuals in human society pursuing their personally optimal strategies do not always achieve the social optimum, the most beneficial state to the society as a whole. Instead, strategies form Nash equilibria which are often socially suboptimal. Society, therefore, has to pay a price of anarchy for the lack of coordination among its members. Here we assess this price of anarchy by analyzing the travel times in road networks of several major cities. Our simulation shows that uncoordinated drivers possibly waste a considerable amount of their travel time. Counterintuitively,simply blocking certain streets can partially improve the traffic conditions. We analyze various complex networks and discuss the possibility of similar paradoxes in physics.Comment: major revisions with multicommodity; Phys. Rev. Lett., accepte

    National surveillance for human and pet contact with oral rabies vaccine baits, 2001–2009

    Get PDF
    Objective—To determine the rate and absolute number of human and pet exposures to oral rabies vaccine (ORV) bait containing liquid vaccinia rabies glycoprotein recombinant vaccine and to evaluate factors that might affect human contact with bait to modify the program and reduce human exposure to the vaccine. Design—Retrospective analysis of surveillance data (2001 to 2009). Sample—Reports on human and pet contact with ORV baits in states with ORV surveillance programs. Procedures—Data were collected from passive, multistate ORV surveillance systems in Alabama, Arizona, Florida, Georgia, Maine, Maryland, Massachusetts, New Hampshire, New Jersey, New York, North Carolina, Ohio, Pennsylvania, Tennessee, Texas, Vermont, Virginia, and West Virginia. Data collected included the nature of human or pet contact with bait and vaccine, the caller’s knowledge of the ORV bait program, local human population density, and other relevant demographic data. Results—All 18 states participated in the surveillance program for at least 1 year, for a combined 68 years of observation. One thousand four hundred thirty-six calls were reported, representing 3,076 found baits (6.89/100,000 baits dropped); 296 (20%) calls were related to human contact with ruptured bait, and 550 (38%) involved pet contact with the bait. Six adverse events in humans were reported, one of which required hospitalization. Fifty-nine adverse events in pets were noted, all of which were nonserious. Conclusions and Clinical Relevance—Findings from surveillance activities have been used to improve baiting strategies and minimize human and pet contact with ORV baits. Overall, human and pet contact with ORV baits was infrequent. Surveillance has led to early identification of persons exposed to ORV and rapid intervention

    To Adapt or Not to Adapt – Consequences of Adapting Driver and Traffic Light Agents

    Get PDF
    One way to cope with the increasing traffic demand is to integrate standard solutions with more intelligent control measures. However, the result of possible interferences between intelligent control or information provision tools and other components of the overall traffic system is not easily predictable. This paper discusses the effects of integrating co-adaptive decision-making regarding route choices (by drivers) and control measures (by traffic lights). The motivation behind this is that optimization of traffic light control is starting to be integrated with navigation support for drivers. We use microscopic, agent-based modelling and simulation, in opposition to the classical network analysis, as this work focuses on the effect of local adaptation. In a scenario that exhibits features comparable to real-world networks, we evaluate different types of adaptation by drivers and by traffic lights, based on local perceptions. In order to compare the performance, we have also used a global level optimization method based on genetic algorithms

    Zinc Therapy for Diarrhoea Increased the Use of Oral Rehydration Therapy and Reduced the Use of Antibiotics in Bangladeshi Children

    Get PDF
    Excessive use of antibiotics for diarrhoea is a major contributing factor towards increasing rates of antimicrobial resistance in developing countries. Zinc therapy for diarrhoea has been shown to be beneficial in controlled efficacy trials, and it is of interest to determine if availability of zinc syrup for treatment of diarrhoea would satisfy the demand for a 'medicine' for diarrhoea, thus reducing the use of antibiotics, without competing with the use of oral rehydration therapy (ORT). This community-based controlled trial was conducted from November 1998 to October 2000, and all children aged 3-59 months in the study area were included. In this trial, the availability of zinc supplements, along with ORT and appropriate education programmes, was associated with significantly higher use of ORT and lower use of antibiotics

    Albumin and mammalian cell culture: implications for biotechnology applications

    Get PDF
    Albumin has a long historical involvement in design of media for the successful culture of mammalian cells, in both the research and commercial fields. The potential application of albumins, bovine or human serum albumin, for cell culture is a by-product of the physico-chemical, biochemical and cell-specific properties of the molecule. In this review an analysis of these features of albumin leads to a consideration of the extracellular and intracellular actions of the molecule, and importantly the role of its interactions with numerous ligands or bioactive factors that influence the growth of cells in culture: these include hormones, growth factors, lipids, amino acids, metal ions, reactive oxygen and nitrogen species to name a few. The interaction of albumin with the cell in relation to these co-factors has a potential impact on metabolic and biosynthetic activity, cell proliferation and survival. Application of this knowledge to improve the performance in manufacturing biotechnology and in the emerging uses of cell culture for tissue engineering and stem cell derived therapies is an important prospect

    A review of zoonotic infection risks associated with the wild meat trade in Malaysia.

    Get PDF
    The overhunting of wildlife for food and commercial gain presents a major threat to biodiversity in tropical forests and poses health risks to humans from contact with wild animals. Using a recent survey of wildlife offered at wild meat markets in Malaysia as a basis, we review the literature to determine the potential zoonotic infection risks from hunting, butchering and consuming the species offered. We also determine which taxa potentially host the highest number of pathogens and discuss the significant disease risks from traded wildlife, considering how cultural practices influence zoonotic transmission. We identify 51 zoonotic pathogens (16 viruses, 19 bacteria and 16 parasites) potentially hosted by wildlife and describe the human health risks. The Suidae and the Cervidae families potentially host the highest number of pathogens. We conclude that there are substantial gaps in our knowledge of zoonotic pathogens and recommend performing microbial food safety risk assessments to assess the hazards of wild meat consumption. Overall, there may be considerable zoonotic risks to people involved in the hunting, butchering or consumption of wild meat in Southeast Asia, and these should be considered in public health strategies
    corecore