Background: The Air Force Health Study collected reproductive outcomes for live-born children of male Air Force veterans of the Vietnam War. Methods: Dioxin values for participants were obtained from blood samples. An...Background: The Air Force Health Study collected reproductive outcomes for live-born children of male Air Force veterans of the Vietnam War. Methods: Dioxin values for participants were obtained from blood samples. Analyses were conducted of occurrence of 16 specific categories of birth defects and developmental disabilities. Children were categorized as conceived before and after the start of participants’ Vietnam War service. Children conceived before the start of Vietnam War service were treated as being conceived when their fathers had unquantifiable dioxin values. Children conceived after the start of Vietnam War service for participants with missing dioxin values were excluded from primary analyses, but were used to assess the impact of their exclusion on conclusions. Correlation between values for specific categories for multiple children fathered by the same participant was accounted for. The dose-response relationship was treated as a step function increasing for dioxin values larger than adaptively identified individual thresholds changing with the specific category. Results: For 15 of 16 specific categories, the probability of occurrence increased substantially for a sufficiently high dioxin level above identified thresholds. Exclusion of children due to missing dioxin likely did not affect these results. Conclusions: Results supported the conclusion of substantial adverse effects on a wide variety of specific categories of birth defects and developmental disabilities due to sufficiently high exposures to dioxin, a toxic contaminant of Agent Orange used for herbicide spraying in the Vietnam War. Results may hold more generally, but might also have been affected by a variety of limitations.展开更多
Urban trees are subjected to different damaging agents throughout their lifetime. The aims of this study were to identify tree damaging agents, and to obtain a Damage Severity Index (DSI) in order to categorize tree h...Urban trees are subjected to different damaging agents throughout their lifetime. The aims of this study were to identify tree damaging agents, and to obtain a Damage Severity Index (DSI) in order to categorize tree health condition at San Juan de Aragon Park. Each tree was identified at species level in 28 randomly established plots in ten sections of the study area. Up to two types of damage were recorded per tree, based on the FIA (Forest Inventory an Analysis Program) protocol, and a DSI was obtained for each damaged tree considering location of damage, nature of the damaging agent and severity. A total of 753 trees were assessed and 12 species and 27 damaging agents were identified. Cankers, galls, the pepper tree psyllid and the red gum lerp psyllid were the most frequent damaging agents. Australian pine, red gum, Mediterranean cypress, Mexican white cedar, and California pepper were the most affected species. The DSI ranged from 3 to 17 and the average was 7.9. Sections J and H and the species California pepper, Australian pine, and Mexican white cedar presented the highest DSI. The tree population had a moderate health condition, while the aforementioned sections and tree species showed the poorest.展开更多
The health monitoring for large-scale structures need to resolve a large number of difficulties,such as the data transmission and distributing information handling.To solve these problems,the technology of multi-agent...The health monitoring for large-scale structures need to resolve a large number of difficulties,such as the data transmission and distributing information handling.To solve these problems,the technology of multi-agent is a good candidate to be used in the field of structural health monitoring.A structural health monitoring system architecture based on multi-agent technology is proposed.The measurement system for aircraft airfoil is designed with FBG,strain gage,and corresponding signal processing circuit.The experiment to determine the location of the concentrate loading on the structure is carried on with the system combined with technologies of pattern recognition and multi-agent.The results show that the system can locate the concentrate loading of the aircraft airfoil at the accuracy of 91.2%.展开更多
An agent-based simulation model hierarchy emulating disease states and behaviors critical to progression of diabetes type 2 was designed and implemented in the DEVS framework. This model was built to approximately rep...An agent-based simulation model hierarchy emulating disease states and behaviors critical to progression of diabetes type 2 was designed and implemented in the DEVS framework. This model was built to approximately reproduce some essential findings that were previously reported for a rather complex model of diabetes progression. Our models are translations of basicelements of this previously reported system dynamics model of diabetes. The system dynamics model, which mimics diabetes progression over an aggregated US population, was disaggregated and reconstructed bottom-up at the individual (agent) level. Four levels of model complexity were defined in order to systematically evaluate which parameters are needed to mimic outputs of the system dynamics model. The four estimated models attempted to replicate stock counts representing disease states in the system dynamics model while estimating impacts of an elderliness factor, obesity factor and health-related behavioral parameters. Health-related behavior was modeled as a simple realization of the Theory of Planned Behavior, a joint function of individual attitude and diffusion of social norms that spread over each agent’s social network. Although the most complex agent-based simulation model contained 31 adjustable parameters, all models were considerably less complex than the system dynamics model which required numerous time series inputs to make its predictions. All three elaborations of the baseline model provided significantly improved fits to the output of the system dynamics model, although behavioral factors appeared to contribute more than the elderliness factor. The results illustrate a promising approach to translate complex system dynamics models into agent-based model alternatives that are both conceptually simpler and capable of capturing main effects of complex local agent-agent interactions.展开更多
Purpose: To investigate 1) the development in the incidence of ESBL-producing bacteria in hospitals and primary health care, 2) the contribution of primary health care to the incidence of ESBL-producing bacteria, and ...Purpose: To investigate 1) the development in the incidence of ESBL-producing bacteria in hospitals and primary health care, 2) the contribution of primary health care to the incidence of ESBL-producing bacteria, and 3) the development in resistance patterns for all Escherichia coli and Klebsiella pneumoniae isolates in relation to antimicrobial consumption in hospitals and primary health care. Methods: ESBL-data were retrospectively collected from bacterial isolates from all specimens received at the Department of Clinical Microbiology from 2003 to 2011 together with the corresponding patient data. ESBL-production was detected in isolates from 1067 of 59,373 patients (1.8%) with an E. coli infection and in 263 of 8660 patients (3.0%) with a K. pneumoniae infection. Results: From 2003 to 2009, an increase in patients with an ESBL-producing isolate occurred in both hospitals and primary health care at the same time as an increased consumption of broad-spectrum antimicrobial agents was seen. Interventions to reduce prescription of cephalosporins and ciprofloxacin at the hospitals from 2010 resulted in a remarkable decrease in patients with ESBL-producing K. pneumoniae whereas a continuing increase was seen in patients with ESBL-producing E. coli both at hospitals and in primary health care. The proportion of patients with community-acquired ESBL-producing E. coli was stable with an increase of only 1.4% from 2007 to 2011. Conclusions: Reduction in prescription of broad-spectrum antimicrobial agents at the hospital level had an important impact on the incidence of ESBL-producing K. pneumoniae, but not on ESBL-producing E. coli.展开更多
文摘Background: The Air Force Health Study collected reproductive outcomes for live-born children of male Air Force veterans of the Vietnam War. Methods: Dioxin values for participants were obtained from blood samples. Analyses were conducted of occurrence of 16 specific categories of birth defects and developmental disabilities. Children were categorized as conceived before and after the start of participants’ Vietnam War service. Children conceived before the start of Vietnam War service were treated as being conceived when their fathers had unquantifiable dioxin values. Children conceived after the start of Vietnam War service for participants with missing dioxin values were excluded from primary analyses, but were used to assess the impact of their exclusion on conclusions. Correlation between values for specific categories for multiple children fathered by the same participant was accounted for. The dose-response relationship was treated as a step function increasing for dioxin values larger than adaptively identified individual thresholds changing with the specific category. Results: For 15 of 16 specific categories, the probability of occurrence increased substantially for a sufficiently high dioxin level above identified thresholds. Exclusion of children due to missing dioxin likely did not affect these results. Conclusions: Results supported the conclusion of substantial adverse effects on a wide variety of specific categories of birth defects and developmental disabilities due to sufficiently high exposures to dioxin, a toxic contaminant of Agent Orange used for herbicide spraying in the Vietnam War. Results may hold more generally, but might also have been affected by a variety of limitations.
文摘Urban trees are subjected to different damaging agents throughout their lifetime. The aims of this study were to identify tree damaging agents, and to obtain a Damage Severity Index (DSI) in order to categorize tree health condition at San Juan de Aragon Park. Each tree was identified at species level in 28 randomly established plots in ten sections of the study area. Up to two types of damage were recorded per tree, based on the FIA (Forest Inventory an Analysis Program) protocol, and a DSI was obtained for each damaged tree considering location of damage, nature of the damaging agent and severity. A total of 753 trees were assessed and 12 species and 27 damaging agents were identified. Cankers, galls, the pepper tree psyllid and the red gum lerp psyllid were the most frequent damaging agents. Australian pine, red gum, Mediterranean cypress, Mexican white cedar, and California pepper were the most affected species. The DSI ranged from 3 to 17 and the average was 7.9. Sections J and H and the species California pepper, Australian pine, and Mexican white cedar presented the highest DSI. The tree population had a moderate health condition, while the aforementioned sections and tree species showed the poorest.
基金supported by the Key Program of the National Science Foundation of China(50830201)Aviation Research Foundation(20060952)+1 种基金the National High Technology Research and Development of China(2007AA03Z117)the Natural Science Foundation of Jiansu Province(08kjd560009)
文摘The health monitoring for large-scale structures need to resolve a large number of difficulties,such as the data transmission and distributing information handling.To solve these problems,the technology of multi-agent is a good candidate to be used in the field of structural health monitoring.A structural health monitoring system architecture based on multi-agent technology is proposed.The measurement system for aircraft airfoil is designed with FBG,strain gage,and corresponding signal processing circuit.The experiment to determine the location of the concentrate loading on the structure is carried on with the system combined with technologies of pattern recognition and multi-agent.The results show that the system can locate the concentrate loading of the aircraft airfoil at the accuracy of 91.2%.
文摘An agent-based simulation model hierarchy emulating disease states and behaviors critical to progression of diabetes type 2 was designed and implemented in the DEVS framework. This model was built to approximately reproduce some essential findings that were previously reported for a rather complex model of diabetes progression. Our models are translations of basicelements of this previously reported system dynamics model of diabetes. The system dynamics model, which mimics diabetes progression over an aggregated US population, was disaggregated and reconstructed bottom-up at the individual (agent) level. Four levels of model complexity were defined in order to systematically evaluate which parameters are needed to mimic outputs of the system dynamics model. The four estimated models attempted to replicate stock counts representing disease states in the system dynamics model while estimating impacts of an elderliness factor, obesity factor and health-related behavioral parameters. Health-related behavior was modeled as a simple realization of the Theory of Planned Behavior, a joint function of individual attitude and diffusion of social norms that spread over each agent’s social network. Although the most complex agent-based simulation model contained 31 adjustable parameters, all models were considerably less complex than the system dynamics model which required numerous time series inputs to make its predictions. All three elaborations of the baseline model provided significantly improved fits to the output of the system dynamics model, although behavioral factors appeared to contribute more than the elderliness factor. The results illustrate a promising approach to translate complex system dynamics models into agent-based model alternatives that are both conceptually simpler and capable of capturing main effects of complex local agent-agent interactions.
文摘Purpose: To investigate 1) the development in the incidence of ESBL-producing bacteria in hospitals and primary health care, 2) the contribution of primary health care to the incidence of ESBL-producing bacteria, and 3) the development in resistance patterns for all Escherichia coli and Klebsiella pneumoniae isolates in relation to antimicrobial consumption in hospitals and primary health care. Methods: ESBL-data were retrospectively collected from bacterial isolates from all specimens received at the Department of Clinical Microbiology from 2003 to 2011 together with the corresponding patient data. ESBL-production was detected in isolates from 1067 of 59,373 patients (1.8%) with an E. coli infection and in 263 of 8660 patients (3.0%) with a K. pneumoniae infection. Results: From 2003 to 2009, an increase in patients with an ESBL-producing isolate occurred in both hospitals and primary health care at the same time as an increased consumption of broad-spectrum antimicrobial agents was seen. Interventions to reduce prescription of cephalosporins and ciprofloxacin at the hospitals from 2010 resulted in a remarkable decrease in patients with ESBL-producing K. pneumoniae whereas a continuing increase was seen in patients with ESBL-producing E. coli both at hospitals and in primary health care. The proportion of patients with community-acquired ESBL-producing E. coli was stable with an increase of only 1.4% from 2007 to 2011. Conclusions: Reduction in prescription of broad-spectrum antimicrobial agents at the hospital level had an important impact on the incidence of ESBL-producing K. pneumoniae, but not on ESBL-producing E. coli.
