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The use of quantitative metrics to gauge the impact of scholarly publications, authors, and disciplines is predicated on the availability of reliable usage and annotation data. Citation and download counts are widely available from digital libraries. However, current annotation systems rely on proprietary labels, refer to journals but not articles or authors, and are manually curated. To address these limitations, we propose a social framework based on crowdsourced annotations of scholars, designed to keep up with the rapidly evolving disciplinary and interdisciplinary landscape. We describe a system called Scholarometer, which provides a service to scholars by computing citation-based impact measures. This creates an incentive for users to provide disciplinary annotations of authors, which in turn can be used to compute disciplinary metrics. We first present the system architecture and several heuristics to deal with noisy bibliographic and annotation data. We report on data sharing and interactive visualization services enabled by Scholarometer. Usage statistics, illustrating the data collected and shared through the framework, suggest that the proposed crowdsourcing approach can be successful. Secondly, we illustrate how the disciplinary bibliometric indicators elicited by Scholarometer allow us to implement for the first time a universal impact measure proposed in the literature. Our evaluation suggests that this metric provides an effective means for comparing scholarly impact across disciplinary boundaries.  相似文献   

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Mobile phone location data is a newly emerging data source of great potential to support human mobility research. However, recent studies have indicated that many users can be easily re-identified based on their unique activity patterns. Privacy protection procedures will usually change the original data and cause a loss of data utility for analysis purposes. Therefore, the need for detailed data for activity analysis while avoiding potential privacy risks presents a challenge. The aim of this study is to reveal the re-identification risks from a Chinese city’s mobile users and to examine the quantitative relationship between re-identification risk and data utility for an aggregated mobility analysis. The first step is to apply two reported attack models, the top N locations and the spatio-temporal points, to evaluate the re-identification risks in Shenzhen City, a metropolis in China. A spatial generalization approach to protecting privacy is then proposed and implemented, and spatially aggregated analysis is used to assess the loss of data utility after privacy protection. The results demonstrate that the re-identification risks in Shenzhen City are clearly different from those in regions reported in Western countries, which prove the spatial heterogeneity of re-identification risks in mobile phone location data. A uniform mathematical relationship has also been found between re-identification risk (x) and data (y) utility for both attack models: y = -ax b+c, (a, b, c>0; 0<x<1), where the exponent b increases with the background knowledge of the attackers. The discovered mathematical relationship provides data publishers with useful guidance on choosing the right tradeoff between privacy and utility. Overall, this study contributes to a better understanding of re-identification risks and a privacy-utility tradeoff benchmark for improving privacy protection when sharing detailed trajectory data.  相似文献   

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The U.S. Environmental Protection Agency has recognized the need to develop a framework for human health risk assessment that puts a perspective on the approaches in practice throughout the Agency. In response, the Agency's Risk Assessment Forum has begun the long-term process of developing a framework for human health risk assessment. The framework will be a communication piece that will lay out the scientific basis, principles, and policy choices underlying past and current risk assessment approaches and will provide recommendations for integrating/harmonizing risk assessment methodologies for all human health endpoints.  相似文献   

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The views expressed in this paper are those of the authors and do not necessarily reflect the views or policies of the USEPA. The U.S. Government has the right to retain a nonexclusive royalty-free license in and to any copyright covering this article. The U.S. Environmental Protection Agency has recognized the need to develop a framework for human health risk assessment that puts a perspective on the approaches in practice throughout the Agency. In response, the USEPA's Risk Assessment Forum has begun the process of developing a framework for human health risk assessment. This paper provides some additional background to the previous review of the framework efforts and notes the Agency's extramural efforts to begin the process of integrating and harmonizing risk assessment approaches for all human health endpoints.  相似文献   

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Statistics in Biosciences - Personalized risk prediction calculators abound in medicine, and they carry important information about the effect of prognostic factors on outcomes of interest. How to...  相似文献   

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This article describes the integration of life-cycle assessment methods with a new input-output model of the world economy to analyze the environmental and economic implications of alternative future diets. The article reviews findings by industrial ecologists about the energy and land required for the production and consumption of alternative foods and diets in several European countries. It also reviews attributes of foods and diets identified by nutritionists as reducing the risks of obesity and major chronic diseases related to the diets of the affluent. The predominantly plant-based Mediterranean-type diet emerges as a dietary scenario that could satisfy both sets of concerns. The likely implications for agriculture and for farm policies of a shift toward this diet from the current average diet in the United States are discussed and shown to be substantial. The one-country studies reviewed in the article provide substantial insights into the potential ramifications of dietary change. Many of the limitations of these studies could be overcome by conducting the analysis in a global framework that represented the relationships among consumption, production, and trade and the physical constraints within which they operate. Analysis of the environmental and economic implications of alternative scenarios describing healthy diets can help stimulate more intensive dialogue, debate, and action among the interested parties; such analysis can both benefit from and contribute to initiatives such as the World Health Organization's global strategy on diet and health, which intends to enlist the support of governments, corporations, and civil society.  相似文献   

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The central challenges in tumor sequencing studies is to identify driver genes and pathways, investigate their functional relationships, and nominate drug targets. The efficiency of these analyses, particularly for infrequently mutated genes, is compromised when subjects carry different combinations of driver mutations. Mutual exclusivity analysis helps address these challenges. To identify mutually exclusive gene sets (MEGS), we developed a powerful and flexible analytic framework based on a likelihood ratio test and a model selection procedure. Extensive simulations demonstrated that our method outperformed existing methods for both statistical power and the capability of identifying the exact MEGS, particularly for highly imbalanced MEGS. Our method can be used for de novo discovery, for pathway-guided searches, or for expanding established small MEGS. We applied our method to the whole-exome sequencing data for 13 cancer types from The Cancer Genome Atlas (TCGA). We identified multiple previously unreported non-pairwise MEGS in multiple cancer types. For acute myeloid leukemia, we identified a MEGS with five genes (FLT3, IDH2, NRAS, KIT, and TP53) and a MEGS (NPM1, TP53, and RUNX1) whose mutation status was strongly associated with survival (p = 6.7 × 10−4). For breast cancer, we identified a significant MEGS consisting of TP53 and four infrequently mutated genes (ARID1A, AKT1, MED23, and TBL1XR1), providing support for their role as cancer drivers.  相似文献   

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The U.S. Environmental Protection Agency (USEPA), Office of Water, is developing a risk assessment protocol for determining microbiological pathogen risks in water (drinking, recreational, waste waters, etc.). This effort has been conducted in collaboration with the International Life Sciences Institute. A microbiological risk assessment framework was prepared and has been peer reviewed in the open literature and vetted at the USEPA and other federal government risk assessment venues. Some goals in development of the Framework were to make it comprehensive, easy to understand and to use, since it is recognized that improvements to the framework structure and instructional material would facilitate its use. The USEPA's Office of Water wishes to develop improved tools, methods, and approaches for conducting the analysis phase for risk assessments and would like to evaluate its efficacy for a broad range of waterborne pathogens in water/wastewater media. Improved understanding of microbiological survival, infectivity, and virulence factors is needed, especially at the genomic and proteomic levels to accurately assess the occurrence and fate of pathogens in water and to predict what intrinsic factors allow pathogens to be invasive and virulent. Development of improved dose-response models (including animal models) for pathogen exposures focusing on the dynamic circumstances of immunity, secondary spread, and sensitive subpopulations, would be useful additions to the Framework. In the future, USEPA may consider establishing comprehensive pathogen risk assessment guidelines that all its program offices can use.  相似文献   

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Wild Pacific salmon populations are in serious decline, and as a result, a number of salmon stocks are listed as threatened or endangered under the Endangered Species Act. Our research identifies and supports the possibility that certain environmental contaminants can alter salmon survival, and as a result may contribute to these species being at risk. We have shown that juvenile chinook salmon (Oncorhynchus tshawytscha) are exposed to polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs) as they migrate through a contaminated urban estuary in Puget Sound WA (the Duwamish Waterway estuary). Immune function was analyzed in these fish by examining the ability of their anterior kidney and splenic leukocytes to produce a primary and secondary in vitro plaque-forming cell (PFC) response to the hapten, trinitrophenyl (TNP), and by determining their susceptibility to a marine pathogen, Vibrio anguillarum. We found that fish outmigrating from the urban estuary produced a significantly lower PFC response to TNP and were more susceptible to the pathogen, compared to juvenile salmon collected from a rural estuary during their outmigration. In the laboratory, we exposed juvenile chinook salmon collected from a hatchery to either a PCB technical mixture or a PAH compound to determine if these contaminants have the potential to alter immune function in salmon. Indeed, we found that salmon exposed in the laboratory to either the PCB mixture or the PAH also produced lower PFC responses and were more susceptible to disease compared to animals treated with the solvent vehicle. In summary, contaminants such as PAHs and PCBs are demonstrated to influence salmon health, and thus have the potential to adversely impact salmon populations.  相似文献   

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The traditional medical model of health and health policy development has focused on individuals and the role of medical care in preventing and treating disease and injury. Recent attention to health inequities and social determinants of health has raised the profile of population heath and evidence-based strategies for improving the health of whole populations. At the same time, risk science has emerged as an important new discipline for the assessment and management of risks to health. This article reviews historical developments in the fields of risk management and population health and proposes a joint population health risk management framework that integrates the key elements of both fields. Applying this integrated approach to managing population health risks will facilitate the development of evidence-based health policy. It will encourage a more systematic and comprehensive evaluation of population health issues and promote the use of a broader suite of interventions to reduce health risks and enhance population health status.  相似文献   

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Background

Evaluations of electric power distribution network risks must address the problems of incomplete information and changing dynamics. A risk evaluation framework should be adaptable to a specific situation and an evolving understanding of risk.

Methods

This study investigates the use of symbolic dynamics to abstract raw data. After introducing symbolic dynamics operators, Kolmogorov-Sinai entropy and Kullback-Leibler relative entropy are used to quantitatively evaluate relationships between risk sub-factors and main factors. For layered risk indicators, where the factors are categorized into four main factors – device, structure, load and special operation – a merging algorithm using operators to calculate the risk factors is discussed. Finally, an example from the Sanya Power Company is given to demonstrate the feasibility of the proposed method.

Conclusion

Distribution networks are exposed and can be affected by many things. The topology and the operating mode of a distribution network are dynamic, so the faults and their consequences are probabilistic.  相似文献   

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To adequately analyze the impacts associated with the rising use of automobiles, an assessment framework is needed that includes environment, health, economic, and sociocultural impacts. Such a framework was developed and applied to a proposed freeway-widening project in Edmonton, Canada. The assessment framework was developed using both Multi-Criteria Analysis and the Ecosystem Approach to Human Health (Ecohealth). Community participation was vital in the application of the assessment framework to this case study. Six stakeholder groups, including community members, City Councillors, and health, environment, and transportation experts, provided needed qualitative data for the assessment framework. Quantitative data were gathered from an ecological study design that associated traffic volumes with respiratory conditions in Edmonton. Community members perceptions about the impacts of the freeway widening differed from those of the expert groups in a number of areas. Environmental and health degradation was more of an issue to community members than to expert groups. Though respiratory conditions were not projected to increase by a significant amount because of the freeway widening, further analysis is necessary on other biophysical and socioeconomic impacts listed in the assessment framework. The divergence in opinion between community members and experts suggests that more communication is needed between these groups in relation to transportation planning. The Ecohealth approach ensures that community concerns are addressed in transportation planning.  相似文献   

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Craniosynostosis, the premature fusion of one or more cranial sutures of the skull, provides a paradigm for investigating the interplay of genetic and environmental factors leading to malformation. Over the past 20 years molecular genetic techniques have provided a new approach to dissect the underlying causes; success has mostly come from investigation of clinical samples, and recent advances in high-throughput DNA sequencing have dramatically enhanced the study of the human as the preferred “model organism.” In parallel, however, we need a pathogenetic classification to describe the pathways and processes that lead to cranial suture fusion. Given the prenatal onset of most craniosynostosis, investigation of mechanisms requires more conventional model organisms; principally the mouse, because of similarities in cranial suture development. We present a framework for classifying genetic causes of craniosynostosis based on current understanding of cranial suture biology and molecular and developmental pathogenesis. Of note, few pathologies result from complete loss of gene function. Instead, biochemical mechanisms involving haploinsufficiency, dominant gain-of-function and recessive hypomorphic mutations, and an unusual X-linked cellular interference process have all been implicated. Although few of the genes involved could have been predicted based on expression patterns alone (because the genes play much wider roles in embryonic development or cellular homeostasis), we argue that they fit into a limited number of functional modules active at different stages of cranial suture development. This provides a useful approach both when defining the potential role of new candidate genes in craniosynostosis and, potentially, for devising pharmacological approaches to therapy.  相似文献   

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Common-pool resource (CPR) dilemmas distinguish themselves from general public good problems by encompassing both social and physical features. This paper examines how a physical mechanism, namely asymmetric payoff; and a social mechanism, reciprocity; simultaneously affect collective cooperation in theoretical water sharing interactions. We present an iterative N-person game theoretic model to investigate the joint effects of these two mechanisms in a linear fully connected river system under three information assumptions. From a simple evolutionary perspective, this paper quantitatively addresses the conditions for Nash Equilibrium in which collective cooperation might be established. The results suggest that direct reciprocity increases every actor’s motivation to contribute to the collective good of the river system. Meanwhile, various upstream and downstream actors manifest individual disparities as a result of the direct reciprocity and asymmetric payoff mechanisms. More specifically, the downstream actors are less willing to cooperate unless there is a high probability that long-term interactions are ensured; however, a greater level of asymmetries is likely to increase upstream actors’ incentives to cooperate even though the interactions could quickly end. The upstream actors also display weak sensitivity to an increase in the total number of actors, which generally results in a reduction in the other actors’ motivation for cooperation. It is also shown that the indirect reciprocity mechanism relaxes the overall conditions for cooperative Nash Equilibrium.  相似文献   

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