268 research outputs found

    The Concept of a CLIOS Analysis Illustrated by the Mexico City Case

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    The term CLIOS (Complex, Large-scale, Integrated, Open Systems) was conceived as way to capture the salient characteristics of a class of systems that are of growing interest to researchers, decisionmakers, policy makers and stakeholders. These systems range from an air traffic control system to the global climate system, and from Boston’s Big Dig to the eBay online trading system. We start by defining the primary characteristics of CLIOS. First, a system is complex when it is composed of a group of interrelated units (component and subsystems), for which the degree and nature of the relationships is imperfectly known – with varying directionality, magnitude and time-scales of interactions among the various subsystems. Second, CLIOS have impacts that are large in magnitude, and often long-lived and of large-scale geographical extent. Third, subsystems within CLIOS are integrated, closely coupled through feedback loops. Finally, by open we mean that CLIOS explicitly include social, political and economic aspects (Sussman, 2000a). Finally, with CLIOS we are as concerned with the complexity of the organizational and institutional parts of the systems as we are with the physical system. In fact, understanding the organizational and institutional structure and its interaction with the physical structure is one of the key potential values of a CLIOS analysis

    A Systems Framework for Assessing Air Quality Impacts of ITS: Application to Mexico City

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    Intelligent Transportation Systems (ITS)—the application of communications and information technology to surface transportation systems—has the potential to improve transportation along several dimensions, from safety to emissions reductions to travel time and reliability. ITS has become a worldwide technology, and many cities in Latin America are currently deploying ITS, from individual technologies to entire ITS Architectures. While improving mobility is at the core of any ITS deployment, in metropolitan areas from Mexico City to Sao Paulo, air quality concerns are such that ignoring possible air quality impacts of ITS technologies represents either a failure to leverage ITS for air quality improvements, or even a risk of running counter to air quality management efforts. While there is a growing number of studies evaluating the air quality benefits of ITS, there are important limitations on the extent to which the results of these studies can be used to support planning of ITS in cities in Latin America. First, the challenges involved in modeling ITS air quality benefits mean that they typically focus on only one or two ITS technologies at a time. Second, air quality and mobility conditions vary greatly across cities, meaning that air quality outcomes will also vary widely. Finally, from a planning standpoint, a more system-wide and qualitative framework is needed to generate the kind of dialogue needed between a diverse number of groups—environmental, transportation, public works, public security, and transport operators—to decide how ITS can meet a metropolitan area needs. In order to address these issues, I develop a systems framework that can encompass a number of ITS technologies and performance measures. Within this systems framework, I look specifically at air quality. Rather than focusing on particular modeling tools, I break down air quality impacts into eight mechanisms that can lead to decreases or increases in mobile source emissions. I will also return briefly to the literature on ITS environmental benefits, to review which mechanisms are included as variables. Finally, I will consider the case of Mexico City, and the interactions between current ITS deployments and air quality

    Nontargeted biomonitoring of halogenated organic compounds in two ecotypes of bottlenose dolphins (Tursiops truncatus) from the Southern California Bight.

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    Targeted environmental monitoring reveals contamination by known chemicals, but may exclude potentially pervasive but unknown compounds. Marine mammals are sentinels of persistent and bioaccumulative contaminants due to their longevity and high trophic position. Using nontargeted analysis, we constructed a mass spectral library of 327 persistent and bioaccumulative compounds identified in blubber from two ecotypes of common bottlenose dolphins (Tursiops truncatus) sampled in the Southern California Bight. This library of halogenated organic compounds (HOCs) consisted of 180 anthropogenic contaminants, 41 natural products, 4 with mixed sources, 8 with unknown sources, and 94 with partial structural characterization and unknown sources. The abundance of compounds whose structures could not be fully elucidated highlights the prevalence of undiscovered HOCs accumulating in marine food webs. Eighty-six percent of the identified compounds are not currently monitored, including 133 known anthropogenic chemicals. Compounds related to dichlorodiphenyltrichloroethane (DDT) were the most abundant. Natural products were, in some cases, detected at abundances similar to anthropogenic compounds. The profile of naturally occurring HOCs differed between ecotypes, suggesting more abundant offshore sources of these compounds. This nontargeted analytical framework provided a comprehensive list of HOCs that may be characteristic of the region, and its application within monitoring surveys may suggest new chemicals for evaluation

    COIM: An Object-Process Based Method for Analyzing Architectures of Complex, Interconnected, Large-Scale Socio-Technical Systems

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    There is growing evidence for the relevance of human behavioral factors in successful development of new products, processes, and services. The evidence is even clearer when the forces affecting the development and evolution of long-lived, large, and open complex socio-technical systems are examined. Methods that study the architecture of these systems can help scholars and practitioners to better understand, manage, and develop socio-technical systems. We propose an approach and a method to address these needs that is grounded in the theory of systems architecture and builds on the strengths of Object Process Methodology (OPM) and the process for representing Complex Large-scale Interconnected Open Socio-technical (CLIOS) systems. We do so by integrating these methods into the CLIOS-OPM Integrated Method (COIM). COIM is conducive to studying a system's architecture and its evolution, as it is enhanced by a set of qualitative methods for answering questions about the reasons (why) and process (how) of change in human-made systems over time.Massachusetts Institute of Technology. Communications Futures ProgramNational Science Foundation (U.S.) (Grant #EIA-0306723

    Environmental Impacts of Emerging Biomass Feedstock Markets: Energy, Agriculture, and the Farmer

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    The tighter linkages between energy and crop markets due to recent climate and energy legislation in the US have large potential environmental impacts beyond carbon sequestration and climate mitigation. These range from effects on water quality and quantity, soil erosion, habitat and biodiversity preservation. These impacts are very location and management-decision specific, as they are the product of atomistic decisions and depend on soil and landscape specific variables. In order to fully understand the effects of biomass markets, the new and stronger linkages and feedback effects between national- and global-scale energy and commodity markets must be properly understood and identified using an integrated perspective. We discuss the various interactions between agricultural and energy markets and their environmental impacts for existing biomass crops and detail how these interactions may be strengthened with the emergence of corn stover as a second generation biofuel feedstock. The tighter coupling of land use and management and energy systems needs to be accounted for to ensure that we have accurate indicators of the sustainability of biomass as an energy resource

    Uptake, accumulation and metabolization of the antidepressant fluoxetine by Mytilus galloprovincialis

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    Fluoxetine, a selective serotonin re-uptake inhibitor (SSRI) antidepressant, is among the most prescribed pharmaceutical active substances worldwide. This study aimed to assess its accumulation and metabolization in the mussel Mytillus galloprovincialis, considered an excellent sentinel species for traditional and emerging pollutants. Mussels were collected from Ria Formosa Lagoon, Portugal, and exposed to a nominal concentration of fluoxetine (75 ng L-1) for 15 days. Approximately 1 g of whole mussel soft tissues was extracted with acetonitrile:formic acid, loaded into an Oasis MCX cartridge, and fluoxetine analysed by liquid chromatography with tandem mass spectrometry (LC-MSn). After 3 days of exposure, fluoxetine was accumulated in 70% of the samples, with a mean of 2.53 ng g(-1) dry weight (d.w.) and norfluoxetine was only detected in one sample (10%), at 3.06 ng g(-1) d.w. After 7 days of exposure, the accumulation of fluoxetine and norfluoxetine increased up to 80 and 50% respectively, and their mean accumulated levels in mussel tissues were up to 4.43 and 2.85 ng g(-1) d.w., respectively. By the end of the exposure period (15 days), both compounds were detected in 100% of the samples (mean of 9.31 and 11.65 ng g(-1) d.w., respectively). Statistical analysis revealed significant accumulation differences between the 3rd and 15th day of exposure for fluoxetine, and between the 3rd and 7th against the 15th day of exposure for norfluoxetine. These results suggest that the fluoxetine accumulated in mussel tissues is likely to be metabolised into norfluoxetine with the increase of the time of exposure, giving evidence that at these realistic environmental concentrations, toxic effects of fluoxetine in mussel tissues may occur. (C) 2016 Elsevier Ltd. All rights reserved

    Toward a New Technology and Policy Program (TPP) Curriculum

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    The mission of the MIT Technology and Policy Program (TPP) is: “Provide an integrative education to scientists and engineers who wish to lead in the development and implementation of responsible strategies and policies for exploitation of technology for the benefit of their communities” (Hastings, 2000). Embedded in the TPP mission statement are several educational requirements: (1) a comprehensive and diverse set of solid analytical skills needed to develop and assess strategies and policies, (2) the flexibility to manage the conflicting interests and values that are present at all stages of the policy process, and (3) the ability to provide leadership at each stage in the policy process. With these concepts in mind, the TPP Curriculum Development Committee will work to place TPP at the forefront of educating the “leaders (researchers and practitioners) of the fields of technology and policy studies” (Hastings, 2000)
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