Diagnosis and incidence risk of clinical canine monocytic ehrlichiosis under field conditions in Southern Europe.

Science.gov (United States)

René-Martellet, Magalie; Lebert, Isabelle; Chêne, Jeanne; Massot, Raphaël; Leon, Marta; Leal, Ana; Badavelli, Stefania; Chalvet-Monfray, Karine; Ducrot, Christian; Abrial, David; Chabanne, Luc; Halos, Lénaïg

2015-01-06

Canine Monocytic Ehrlichiosis (CME), due to the bacterium Ehrlichia canis and transmitted by the brown dog tick Rhipicephalus sanguineus, is a major tick-borne disease in southern Europe. In this area, infections with other vector-borne pathogens (VBP) are also described and result in similar clinical expression. The aim of the present study was to evaluate the incidence risk of clinical CME in those endemic areas and to assess the potential involvement of other VBP in the occurrence of clinical and/or biological signs evocative of the disease. The study was conducted from April to November 2011 in veterinary clinics across Italy, Spain and Portugal. Sick animals were included when fitting at least three clinical and/or biological criteria compatible with ehrlichiosis. Serological tests (SNAP®4Dx, SNAP®Leish tests, Idexx, USA) and diagnostic PCR for E. canis, Anaplasma platys, Anaplasma phagocytophilum, Babesia spp, Hepatozoon canis and Leishmania infantum detection were performed to identify the etiological agents. Ehrlichiosis was considered when three clinical and/or biological suggestive signs were associated with at least one positive paraclinical test (serology or PCR). The annual incidence risk was calculated and data were geo-referenced for map construction. The probabilities of CME and other vector-borne diseases when facing clinical and/or biological signs suggestive of CME were then evaluated. A total of 366 dogs from 78 veterinary clinics were enrolled in the survey. Among them, 99 (27%) were confirmed CME cases, which allowed an estimation of the average annual incidence risk of CME amongst the investigated dog population to be 0.08%. Maps showed an increasing gradient of CME incidence risk from northern towards southern areas, in particular in Italy. It also suggested the existence of hot-spots of infections by VBP in Portugal. In addition, the detection of other VBP in the samples was common and the study demonstrated that a dog with clinical signs

Ehrlichiosis: A Vector-Borne Disease of Animals and Humans. Current Topics in Veterinary Medicine and Animal Science, Volume 54

Science.gov (United States)

1990-01-01

petechial fever . Vet. Rec. 84:149-150. 25. Stephenson, E. If., A. D. King, R. B. Moeiller, J. C. W~illiam , C. J. Holland, and M. Ristic. 1989...internationally. The same group joined a national eff’ort to decipher another mysterious disease known as Potomac horse fever (PHF). They used the same...an Ehrlichiosis-like syndrome, confusable, but distinct from Rocky Mountain spotted fever (without ; rash) were diagnosed and strongly associated

Gray wolf exposure to emerging vector-borne diseases in Wisconsin with comparison to domestic dogs and humans

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Jara, Rocio F.; Wydeven, Adrian P.; Samuel, Michael D.

2016-01-01

World-wide concern over emerging vector-borne diseases has increased in recent years for both animal and human health. In the United Sates, concern about vector-borne diseases in canines has focused on Lyme disease, anaplasmosis, ehrlichiosis, and heartworm which infect domestic and wild canids. Of these diseases, Lyme and anaplasmosis are also frequently diagnosed in humans. Gray wolves (Canis lupus) recolonized Wisconsin in the 1970s, and we evaluated their temporal and geographic patterns of exposure to these four vector-borne diseases in Wisconsin as the population expanded between 1985 and 2011. A high proportion of the Wisconsin wolves were exposed to the agents that cause Lyme (65.6%) and anaplasma (47.7%), and a smaller proportion to ehrlichiosis (5.7%) and infected with heartworm (9.2%). Wolf exposure to tick borne diseases was consistently higher in older animals. Wolf exposure was markedly higher than domestic dog (Canis familiaris) exposure for all 4 disease agents during 2001–2013. We found a cluster of wolf exposure to Borrelia burgdorferi in northwestern Wisconsin, which overlaps human and domestic dog clusters for the same pathogen. In addition, wolf exposure to Lyme disease in Wisconsin has increased, corresponding with the increasing human incidence of Lyme disease in a similar time period. Despite generally high prevalence of exposure none of these diseases appear to have slowed the growth of the Wisconsin wolf population.

Lymph node hemophagocytosis in rickettsial diseases: a pathogenetic role for CD8 T lymphocytes in human monocytic ehrlichiosis (HME?

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Dumler J Stephen

2006-07-01

Full Text Available Abstract Background Human monocytic ehrlichiosis (HME and Rocky Mountain spotted fever (RMSF are caused by Ehrlichia chaffeensis and Rickettsia rickettsii, respectively. The pathogenesis of RMSF relates to rickettsia-mediated vascular injury, but it is unclear in HME. Methods To study histopathologic responses in the lymphatic system for correlates of immune injury, lymph nodes from patients with HME (n = 6 and RMSF (n = 5 were examined. H&E-stained lymph node tissues were examined for five histopathologic features, including hemophagocytosis, cellularity, necrosis, and vascular congestion and edema. The relative proportions of CD68 macrophages, CD8 and CD4 T lymphocytes, and CD20 B lymphocytes were evaluated by immunohistochemical staining. Results Hemophagocytosis was similar in HME and RMSF, and was greater than in control cases (p = .015. Cellularity in HME was not different from controls, whereas RMSF lymph nodes were markedly less cellular (p E. chaffeensis-infected mononuclear phagocytes were infrequent compared to R. rickettsii-infected endothelial cells. More CD8 cells in lymph nodes were observed with HME (p Conclusion Hemophagocytosis, CD8 T cell expansion, and the paucity of infected cells in HME, suggest that E. chaffeensis infection leads to macrophage activation and immune-mediated injury.

Gray Wolf Exposure to Emerging Vector-Borne Diseases in Wisconsin with Comparison to Domestic Dogs and Humans.

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Rocio F Jara

Full Text Available World-wide concern over emerging vector-borne diseases has increased in recent years for both animal and human health. In the United Sates, concern about vector-borne diseases in canines has focused on Lyme disease, anaplasmosis, ehrlichiosis, and heartworm which infect domestic and wild canids. Of these diseases, Lyme and anaplasmosis are also frequently diagnosed in humans. Gray wolves (Canis lupus recolonized Wisconsin in the 1970s, and we evaluated their temporal and geographic patterns of exposure to these four vector-borne diseases in Wisconsin as the population expanded between 1985 and 2011. A high proportion of the Wisconsin wolves were exposed to the agents that cause Lyme (65.6% and anaplasma (47.7%, and a smaller proportion to ehrlichiosis (5.7% and infected with heartworm (9.2%. Wolf exposure to tick borne diseases was consistently higher in older animals. Wolf exposure was markedly higher than domestic dog (Canis familiaris exposure for all 4 disease agents during 2001-2013. We found a cluster of wolf exposure to Borrelia burgdorferi in northwestern Wisconsin, which overlaps human and domestic dog clusters for the same pathogen. In addition, wolf exposure to Lyme disease in Wisconsin has increased, corresponding with the increasing human incidence of Lyme disease in a similar time period. Despite generally high prevalence of exposure none of these diseases appear to have slowed the growth of the Wisconsin wolf population.

MACROMICROSCOPIC AND ULTRAMICROSCOPIC CHARACTERISTICS OF THE HART AND ITS BLOOD VESSELS IN MICE EHRLICHIOSIS INFECTION

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Pokhil S. I.

2013-12-01

Full Text Available The macromicroscopic, ultramicroscopic studying change’s in the hart and its blood vessels in unlinear immunocomprometive laboratory male and female mice with the experimental ehrlichiosis is presented in this article. The cardiac destructive and degenerative changes,cardiomyopathy, cardiosclerosis had been established inexperimental animal group’s. The blood vessels endothelial lieyr disorganization, stasis, thrombosis has been noted.

Toxoplasma gondii genotyping in a dog co-infected with distemper virus and ehrlichiosis rickettsia Genotipagem de Toxoplasma gondii em cão co-infectado com o vírus da cinomose e a rickettsia da erliquiose

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Leandro d'Arc Moretti

2006-12-01

Full Text Available This paper reports a toxoplasmosis, erhlichiosis and distemper co-infection in a dog with an exuberant neuropathological clinical picture. Primary involvement was discussed based on information collected in the analysis of the clinical case, such as neurological impairment, epidemiological data, poor immunoprophylactic scheme of the dog affected and the role of these diseases on immunosuppression. Canine distemper and ehrlichiosis were diagnosed based on epidemiologic data, clinical signs, hematological and cytological evaluation. Toxoplasma gondii was isolated and genetically characterized as Type I using restriction analysis (RFLP with SAG-2 genes. Immunosuppression features of both dogs and human beings are discussed, as well as implications on animal and public health. This is the first report on toxoplasmosis, ehrlichiosis and distemper co-infection in a dog in Brazil, associated with genotyping determination of the T. gondii strain involved.Este artigo relata a co-infecção tripla pelos agentes da cinomose, erliquiose e toxoplasmose em um cão com acentuado quadro clínico neuropático. Discute-se a doença primária baseando-se em dados clínicos, epidemiológicos, no protocolo imunoprofilático inadequado e no papel daquelas doenças na imunossupressão. A cinomose e a erliquiose foram diagnosticadas mediante a situação epidemiológica da região e sinais clínicos compatíveis, aliados aos achados de hemograma e citologia. Utilizando-se a análise de restrição (RFLP com os genes SAG-2, caracterizou-se geneticamente a linhagem de Toxoplasma gondii isolada, como pertencente ao Tipo I. Discutem-se aspectos de imunossupressão, tanto em cães quanto em seres humanos, bem como suas implicações em saúde pública e animal. Este é o primeiro relato de infecção tripla pelos agentes da toxoplasmose, erliquiose e cinomose no Brasil, associado com a genotipificação da estirpe de T. gondii envolvida.

Embodied artificial agents for understanding human social cognition.

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Wykowska, Agnieszka; Chaminade, Thierry; Cheng, Gordon

2016-05-05

In this paper, we propose that experimental protocols involving artificial agents, in particular the embodied humanoid robots, provide insightful information regarding social cognitive mechanisms in the human brain. Using artificial agents allows for manipulation and control of various parameters of behaviour, appearance and expressiveness in one of the interaction partners (the artificial agent), and for examining effect of these parameters on the other interaction partner (the human). At the same time, using artificial agents means introducing the presence of artificial, yet human-like, systems into the human social sphere. This allows for testing in a controlled, but ecologically valid, manner human fundamental mechanisms of social cognition both at the behavioural and at the neural level. This paper will review existing literature that reports studies in which artificial embodied agents have been used to study social cognition and will address the question of whether various mechanisms of social cognition (ranging from lower- to higher-order cognitive processes) are evoked by artificial agents to the same extent as by natural agents, humans in particular. Increasing the understanding of how behavioural and neural mechanisms of social cognition respond to artificial anthropomorphic agents provides empirical answers to the conundrum 'What is a social agent?' © 2016 The Authors.

Bridging humans via agent networks

International Nuclear Information System (INIS)

Ishida, Toru

1994-01-01

Recent drastic advance in telecommunication networks enabled the human organization of new class, teleorganization, which differ from any existing organization in that the organization which is easy to create by using telecommunication networks is virtual and remote, that people can join multiple organizations simultaneously, and that the organization can involve people who may not know each other. In order to enjoy the recent advance in telecommunication, the agent networks to help people organize themselves are needed. In this paper, an architecture of agent networks, in which each agent learns the preference or the utility functioin of the owner, and acts on behalf of the owner in maintaining the organization, is proposed. When an agent networks supports a human organization, the conventional human interface is divided into personal and social interfaces. The functionalities of the social interface in teleconferencing and telelearning were investigated. In both cases, the existence of B-ISDN is assumed, and the extension to the business meeting scheduling using personal handy phone (PHS) networks with personal digital assistant (PDA) terminals is expected. These circumstances are described. Mutual selection protocols (MSP) and their dynamic properties are explained. (K.I.)

Artificial agents learning human fairness

NARCIS (Netherlands)

Jong, de S.; Tuyls, K.P.; Verbeeck, K.; Padgham, xx; Parkes, xx

2008-01-01

Recent advances in technology allow multi-agent systems to be deployed in cooperation with or as a service for humans. Typically, those systems are designed assuming individually rational agents, according to the principles of classical game theory. However, research in the field of behavioral

Anti-Hepatozoon canis serum antibodies and gamonts in naturally-occurring canine monocytic ehrlichiosis.

Science.gov (United States)

Mylonakis, Mathios E; Leontides, Leonidas; Gonen, Liat; Billinis, Charalambos; Koutinas, Alexander F; Baneth, Gad

2005-05-15

The prevalence of IgG antibodies to Hepatozoon canis and the presence of gamonts in the blood and hemolymphatic tissues were studied in dogs with canine monocytic ehrlichiosis (CME) caused by Ehrlichia canis. Both pathogens are transmitted by the tick Rhipicephalus sanguineus. Forty-five out of 69 (65.2%) dogs with CME were seropositive to H. canis by an enzyme-linked immunosorbent assay (ELISA). Intra-neutrophilic gamonts of H. canis were found in 2 out of 69 dogs (2.9%) comprising 4.5% of the seropositive dogs. The present study indicated that the prevalence of antibodies to H. canis was high among dogs with CME in an area where both infections are endemic. However, previous exposure to H. canis was not found as an important contributor to clinical or clinicopathologic abnormalities found in dogs with CME.

A Taxonomy of Human-Agent Team Collaborations

NARCIS (Netherlands)

Neef, R.M.

2006-01-01

Future command teams will be heavily supported by artificial actors. This paper introduces a taxonomy of collaboration types in human – agent teams. Using two classifying dimensions, coordination type and collaboration type, eight different classes of human – agent collaborations transpire. These

An Assessment of Whole Blood and Fractions by Nested PCR as a DNA Source for Diagnosing Canine Ehrlichiosis and Anaplasmosis

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Tereza Emmanuelle de Farias Rotondano

2012-01-01

Full Text Available Ehrlichiosis and anaplasmosis are tick-borne diseases. Ehrlichia canis and Anaplasma platys infect mainly white cells and platelets, respectively. The main DNA source for PCR is peripheral blood, but the potential of blood cell fractions has not been extensively investigated. This study aims at assessment of whole blood (WB and blood fractions potential in nested PCR (nPCR to diagnose canine ehrlichiosis and anaplasmosis. The 16S rRNA gene was amplified in 71.4, 17.8, 31.57, and 30% of the WB, granulocyte (G, mononuclear cells (M, and buffy coat (BC samples. Compared to the WB, the sensitivity of the PCR was 42.86% for the M, and BC fractions, 21.43% for the G, and 33.33% for the blood clot (C. There was fair agreement between the WB and M, BC and C, and slight with the G. Fair agreement occurred between the nPCR and morulae in the blood smear. One animal was coinfected with A. platys and E. canis. This study provided the first evidence of A. platys infection in dogs in Paraíba, Brazil, and demonstrated that WB is a better DNA source than blood fractions to detect Ehrlichia and Anaplasma by nPCR, probably because of the plasma bacterial concentration following host cell lysis.

Survey for Tick-Borne Zoonoses in the State of Espirito Santo, Southeastern Brazil

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Spolidorio, Mariana G.; Labruna, Marcelo B.; Machado, Rosangela Z.; Moraes-Filho, Jonas; Zago, Augusto M.; Donatele, Dirlei M.; Pinheiro, Sônia R.; Silveira, Iara; Caliari, Késia M.; Yoshinari, Natalino H.

2010-01-01

Blood samples collected from 201 humans, 92 dogs, and 27 horses in the state of Espirito Santo, Brazil, were tested by polymerase chain reaction, indirect immunofluorescence assays, and indirect enzyme-linked immunosorbent assay for tick-borne diseases (rickettsiosis, ehrlichiosis, anaplasmosis, borreliosis, babesiosis). Our results indicated that the surveyed counties are endemic for spotted fever group rickettsiosis because sera from 70 (34.8%) humans, 7 (7.6%) dogs, and 7 (25.9%) horses were reactive to at least one of the six Rickettsia species tested. Although there was evidence of ehrlichiosis (Ehrlichia canis) and babesiosis (Babesia canis vogeli, Theileria equi) in domestic animals, no human was positive for babesiosis and only four individuals were serologically positive for E. canis. Borrelia burgdorferi-serologic reactive sera were rare among humans and horses, but encompassed 51% of the canine samples, suggesting that dogs and their ticks can be part of the epidemiological cycle of the causative agent of the Brazilian zoonosis, named Baggio-Yoshinari Syndrome. PMID:20595502

Incorporating BDI Agents into Human-Agent Decision Making Research

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Kamphorst, Bart; van Wissen, Arlette; Dignum, Virginia

Artificial agents, people, institutes and societies all have the ability to make decisions. Decision making as a research area therefore involves a broad spectrum of sciences, ranging from Artificial Intelligence to economics to psychology. The Colored Trails (CT) framework is designed to aid researchers in all fields in examining decision making processes. It is developed both to study interaction between multiple actors (humans or software agents) in a dynamic environment, and to study and model the decision making of these actors. However, agents in the current implementation of CT lack the explanatory power to help understand the reasoning processes involved in decision making. The BDI paradigm that has been proposed in the agent research area to describe rational agents, enables the specification of agents that reason in abstract concepts such as beliefs, goals, plans and events. In this paper, we present CTAPL: an extension to CT that allows BDI software agents that are written in the practical agent programming language 2APL to reason about and interact with a CT environment.

Modeling and simulating human teamwork behaviors using intelligent agents

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Fan, Xiaocong; Yen, John

2004-12-01

Among researchers in multi-agent systems there has been growing interest in using intelligent agents to model and simulate human teamwork behaviors. Teamwork modeling is important for training humans in gaining collaborative skills, for supporting humans in making critical decisions by proactively gathering, fusing, and sharing information, and for building coherent teams with both humans and agents working effectively on intelligence-intensive problems. Teamwork modeling is also challenging because the research has spanned diverse disciplines from business management to cognitive science, human discourse, and distributed artificial intelligence. This article presents an extensive, but not exhaustive, list of work in the field, where the taxonomy is organized along two main dimensions: team social structure and social behaviors. Along the dimension of social structure, we consider agent-only teams and mixed human-agent teams. Along the dimension of social behaviors, we consider collaborative behaviors, communicative behaviors, helping behaviors, and the underpinning of effective teamwork-shared mental models. The contribution of this article is that it presents an organizational framework for analyzing a variety of teamwork simulation systems and for further studying simulated teamwork behaviors.

A human capital predictive model for agent performance in contact centres

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Chris Jacobs

2011-10-01

Research purpose: The primary focus of this article was to develop a theoretically derived human capital predictive model for agent performance in contact centres and Business Process Outsourcing (BPO based on a review of current empirical research literature. Motivation for the study: The study was motivated by the need for a human capital predictive model that can predict agent and overall business performance. Research design: A nonempirical (theoretical research paradigm was adopted for this study and more specifically a theory or model-building approach was followed. A systematic review of published empirical research articles (for the period 2000–2009 in scholarly search portals was performed. Main findings: Eight building blocks of the human capital predictive model for agent performance in contact centres were identified. Forty-two of the human capital contact centre related articles are detailed in this study. Key empirical findings suggest that person– environment fit, job demands-resources, human resources management practices, engagement, agent well-being, agent competence; turnover intention; and agent performance are related to contact centre performance. Practical/managerial implications: The human capital predictive model serves as an operational management model that has performance implications for agents and ultimately influences the contact centre’s overall business performance. Contribution/value-add: This research can contribute to the fields of human resource management (HRM, human capital and performance management within the contact centre and BPO environment.

Social Psychology Of Persuasion Applied To Human-agent Interaction

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Shenghua Liu

2008-01-01

Full Text Available This paper discusses and evaluates the application of a social psychologically enriched, user-centered approach to agent architecture design. The major aim is to facilitate human-agent interaction (HAI by making agents not only algorithmically more intelligent but also socially more skillful in communicating with the user. A decision-making model and communicative argumentation strategies have been incorporated into the agent architecture. In the presented content resource management experiments, enhancement of human task performance is demonstrated for users that are supported by a persuasive agent. This superior performance seems to be rooted in a more trusting collaborative relationship between the user and the agent, rather than in the appropriateness of the agent's decision-making suggestions alone. In particular, the second experiment demonstrated that interface interaction design should follow the principles of task-orientation and implicitness. Making the influence of the agent too salient can trigger counterintentional effects, such as users' discomfort and psychological reactance.

Human Health Consequences of Use of Antimicrobial Agents in Aquaculture

DEFF Research Database (Denmark)

Heuer, Ole Eske; Kruse, H.; Grave, K.

2009-01-01

industry in many regions of the world and the widespread, intensive, and often unregulated use of antimicrobial agents in this area of animal production, efforts are needed to prevent development and spread of antimicrobial resistance in aquaculture to reduce the risk to human health....... in aquaculture, several are classified by the World Health Organisation as critically important for use in humans. Occurrence of resistance to these antimicrobial agents in human pathogens severely limits the therapeutic options in human infections. Considering the rapid growth and importance of aquaculture...... gene transfer and reach human pathogens, or drug-resistant pathogens from the aquatic environment may reach humans directly. Horizontal gene transfer may occur in the aquaculture environment, in the food chain, or in the human intestinal tract. Among the antimicrobial agents commonly used...

Comparability of Conflict Opportunities in Human-to-Human and Human-to-Agent Online Collaborative Problem Solving

Science.gov (United States)

Rosen, Yigal

2014-01-01

Students' performance in human-to-human and human-to-agent collaborative problem solving assessment task is investigated in this paper. A secondary data analysis of the research reported by Rosen and Tager (2013) was conducted in order to investigate the comparability of the opportunities for conflict situations in human-to-human and…

Intelligent Agent Transparency in Human-Agent Teaming for Multi-UxV Management.

Science.gov (United States)

Mercado, Joseph E; Rupp, Michael A; Chen, Jessie Y C; Barnes, Michael J; Barber, Daniel; Procci, Katelyn

2016-05-01

We investigated the effects of level of agent transparency on operator performance, trust, and workload in a context of human-agent teaming for multirobot management. Participants played the role of a heterogeneous unmanned vehicle (UxV) operator and were instructed to complete various missions by giving orders to UxVs through a computer interface. An intelligent agent (IA) assisted the participant by recommending two plans-a top recommendation and a secondary recommendation-for every mission. A within-subjects design with three levels of agent transparency was employed in the present experiment. There were eight missions in each of three experimental blocks, grouped by level of transparency. During each experimental block, the IA was incorrect three out of eight times due to external information (e.g., commander's intent and intelligence). Operator performance, trust, workload, and usability data were collected. Results indicate that operator performance, trust, and perceived usability increased as a function of transparency level. Subjective and objective workload data indicate that participants' workload did not increase as a function of transparency. Furthermore, response time did not increase as a function of transparency. Unlike previous research, which showed that increased transparency resulted in increased performance and trust calibration at the cost of greater workload and longer response time, our results support the benefits of transparency for performance effectiveness without additional costs. The current results will facilitate the implementation of IAs in military settings and will provide useful data to the design of heterogeneous UxV teams. © 2016, Human Factors and Ergonomics Society.

Socially intelligent autonomous agents that learn from human reward

NARCIS (Netherlands)

Li, Guangliang

2016-01-01

In the future, autonomous agents will operate in human inhabited environments in many real world applications and become an integral part of human’s daily lives. Therefore, when autonomous agents enter into the real world, they need to adapt to many novel, dynamic and complex situations that cannot

Human-Robot Teaming in a Multi-Agent Space Assembly Task

Science.gov (United States)

Rehnmark, Fredrik; Currie, Nancy; Ambrose, Robert O.; Culbert, Christopher

2004-01-01

NASA's Human Space Flight program depends heavily on spacewalks performed by pairs of suited human astronauts. These Extra-Vehicular Activities (EVAs) are severely restricted in both duration and scope by consumables and available manpower. An expanded multi-agent EVA team combining the information-gathering and problem-solving skills of humans with the survivability and physical capabilities of robots is proposed and illustrated by example. Such teams are useful for large-scale, complex missions requiring dispersed manipulation, locomotion and sensing capabilities. To study collaboration modalities within a multi-agent EVA team, a 1-g test is conducted with humans and robots working together in various supporting roles.

You Look Human, But Act Like a Machine: Agent Appearance and Behavior Modulate Different Aspects of Human-Robot Interaction.

Science.gov (United States)

Abubshait, Abdulaziz; Wiese, Eva

2017-01-01

Gaze following occurs automatically in social interactions, but the degree to which gaze is followed depends on whether an agent is perceived to have a mind, making its behavior socially more relevant for the interaction. Mind perception also modulates the attitudes we have toward others, and determines the degree of empathy, prosociality, and morality invested in social interactions. Seeing mind in others is not exclusive to human agents, but mind can also be ascribed to non-human agents like robots, as long as their appearance and/or behavior allows them to be perceived as intentional beings. Previous studies have shown that human appearance and reliable behavior induce mind perception to robot agents, and positively affect attitudes and performance in human-robot interaction. What has not been investigated so far is whether different triggers of mind perception have an independent or interactive effect on attitudes and performance in human-robot interaction. We examine this question by manipulating agent appearance (human vs. robot) and behavior (reliable vs. random) within the same paradigm and examine how congruent (human/reliable vs. robot/random) versus incongruent (human/random vs. robot/reliable) combinations of these triggers affect performance (i.e., gaze following) and attitudes (i.e., agent ratings) in human-robot interaction. The results show that both appearance and behavior affect human-robot interaction but that the two triggers seem to operate in isolation, with appearance more strongly impacting attitudes, and behavior more strongly affecting performance. The implications of these findings for human-robot interaction are discussed.

Ixodes ricinus as vector and reservoir of Borrelia burgdorferi in an urban environment

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Rajković Dragana V.

2005-01-01

Full Text Available As specific arthropods, ticks in urban environments transmit the agents of dangerous contagious diseases endangering human and animal health. They are vectors of numerous infective agents that cause serious diseases of animals such as babesiosis and ehrlichiosis. Tick populations maintain and transmit an increas­ing number of different infective agents. In regard to the human population, they transmit the agents of tick encephalitis, Omsk hemorrhagic disease, Crim-Congo hemorrhagic disease, Kyasa-nur forest fever, ixodid fever, Q fever, Rocky Mountain spotted fever, tularemia, Siberian tick typhus and Lyme disease the last of which according to acarological references has become the dominant zoonosis in over 140 of the world's countries. In urban environments ticks represent problem both for their epidemiological significance and as organisms whose presence disturbs people during their work and rest. In Europe, the two most fre­quent species and Ixodes ricinus and Ixodes persulcatus. Both species have a wide spectrum of hosts.

Retrospective study (1998-2001 on canine ehrlichiosis in Belo Horizonte, MG, Brazil Estudo retrospectivo (1998 a 2001 da erliquiose canina em Belo Horizonte

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S.M. Moreira

2003-04-01

Full Text Available The present work describes a retrospective study of clinical cases of ehrlichiosis in dogs examined from March 1998 to September 2001. From the clinical records with laboratorial confirmation of Ehrlichia canis or E. platys infections, the following parameters were analyzed: demographic aspects (age, race, sex, period of the year and origin, clinical characteristics (body temperature, exposure to ticks and clinical signs, and hematological characteristics (blood cell counts and type of infected cell. A total of 194 clinical records were analyzed, from which 31 animals were infected with E. canis and 21 animals with E. platys. The number of cases of canine ehrlichiosis increased considerably from the year 2000 onwards, and 24.4% of the cases occurred in 13- to 24-month-old animals, in different urban and per-urban regions of the municipality of Belo Horizonte. The most frequent symptoms were fever, anorexia, apathy, abdominal pain, lymphadenopathy and dispnea. Regarding hematological alterations, 70.3% of the animals presented anemia, 50% presented thrombocytopenia and 30% leukopenia, and most E. canis morulae were seen in monocytes. The results point to the importance of canine ehrlichiosis, as 35.9% of the dogs with suspected hemoparasitic diseases were infected with Ehrlichia canis or E. platys.O presente trabalho descreve um estudo retrospectivo da casuística clínica de erliquiose em cães atendidos entre março de 1998 e setembro de 2001. Foram analisadas 194 fichas clínicas de animais com suspeita de hemoparasitoses, nas quais 31 cães foram diagnosticados com Ehrlichia canis e 21 com Ehrlichia platys, por meio de exame parasitológico direto de esfregaços sangüíneos. Foram considerados alguns aspectos demográficos (idade, raça, sexo, época do ano e região de origem, características clínicas (temperatura corporal, presença e/ou histórico de carrapatos e sinais clínicos e hematológicas (hemograma completo e célula parasitada

A Framework for Agent-based Human Interaction Support

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Axel Bürkle

2008-10-01

Full Text Available In this paper we describe an agent-based infrastructure for multimodal perceptual systems which aims at developing and realizing computer services that are delivered to humans in an implicit and unobtrusive way. The framework presented here supports the implementation of human-centric context-aware applications providing non-obtrusive assistance to participants in events such as meetings, lectures, conferences and presentations taking place in indoor "smart spaces". We emphasize on the design and implementation of an agent-based framework that supports "pluggable" service logic in the sense that the service developer can concentrate on coding the service logic independently of the underlying middleware. Furthermore, we give an example of the architecture's ability to support the cooperation of multiple services in a meeting scenario using an intelligent connector service and a semantic web oriented travel service.

Hacker Within! Ehrlichia chaffeensis Effector Driven Phagocyte Reprogramming Strategy

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Taslima Taher Lina

2016-05-01

Full Text Available Ehrlichia chaffeensis is a small, gram negative, obligately intracellular bacterium that preferentially infects mononuclear phagocytes. It is the etiologic agent of human monocytotropic ehrlichiosis (HME, an emerging life-threatening tick-borne zoonosis. Mechanisms by which E. chaffeensis establishes intracellular infection, and avoids host defenses are not well understood, but involve functionally relevant host-pathogen interactions associated with tandem and ankyrin repeat effector proteins. In this review, we discuss the recent advances in our understanding of the molecular and cellular mechanisms that underlie Ehrlichia host cellular reprogramming strategies that enable intracellular survival.

The Tick Salivary Protein Sialostatin L2 Inhibits Caspase-1-Mediated Inflammation during Anaplasma phagocytophilum Infection

Czech Academy of Sciences Publication Activity Database

Chen, G.; Wang, X.; Sakhon, O. S.; Sohail, M.; Brown, L.J.; Sircar, M.; Snyder, G.A.; Sundberg, E.J.; Ulland, T.K.; Olivier, A.K.; Andersen, J. F.; Zhou, Y.; Shi, G.-P.; Sutterwala, F.S.; Kotsyfakis, Michalis; Pedra, J. H. F.

2014-01-01

Roč. 82, č. 6 (2014), s. 2553-2564 ISSN 0019-9567 Institutional support: RVO:60077344 Keywords : granulocytic ehrlichiosis agent * Ixodes scapularis * tumor necrosis factor Subject RIV: EC - Immunology Impact factor: 3.731, year: 2014

Chemerin is an antimicrobial agent in human epidermis.

Directory of Open Access Journals (Sweden)

Magdalena Banas

Full Text Available Chemerin, a chemoattractant ligand for chemokine-like receptor 1 (CMKLR1 is predicted to share similar tertiary structure with antibacterial cathelicidins. Recombinant chemerin has antimicrobial activity. Here we show that endogenous chemerin is abundant in human epidermis, and that inhibition of bacteria growth by exudates from organ cultures of primary human skin keratinocytes is largely chemerin-dependent. Using a panel of overlapping chemerin-derived synthetic peptides, we demonstrate that the antibacterial activity of chemerin is primarily mediated by Val(66-Pro(85, which causes direct bacterial lysis. Therefore, chemerin is an antimicrobial agent in human skin.

Modeling and simulation of virtual human's coordination based on multi-agent systems

Science.gov (United States)

Zhang, Mei; Wen, Jing-Hua; Zhang, Zu-Xuan; Zhang, Jian-Qing

2006-10-01

The difficulties and hotspots researched in current virtual geographic environment (VGE) are sharing space and multiusers operation, distributed coordination and group decision-making. The theories and technologies of MAS provide a brand-new environment for analysis, design and realization of distributed opening system. This paper takes cooperation among virtual human in VGE which multi-user participate in as main researched object. First we describe theory foundation truss of VGE, and present the formalization description of Multi-Agent System (MAS). Then we detailed analyze and research arithmetic of collectivity operating behavior learning of virtual human based on best held Genetic Algorithm(GA), and establish dynamics action model which Multi-Agents and object interact dynamically and colony movement strategy. Finally we design a example which shows how 3 evolutional Agents cooperate to complete the task of colony pushing column box, and design a virtual world prototype of virtual human pushing box collectively based on V-Realm Builder 2.0, moreover we make modeling and dynamic simulation with Simulink 6.

Comparison of oxime reactivation and aging of nerve agent-inhibited monkey and human acetylcholinesterases.

Science.gov (United States)

Luo, Chunyuan; Tong, Min; Maxwell, Donald M; Saxena, Ashima

2008-09-25

Non-human primates are valuable animal models that are used for the evaluation of nerve agent toxicity as well as antidotes and results from animal experiments are extrapolated to humans. It has been demonstrated that the efficacy of an oxime primarily depends on its ability to reactivate nerve agent-inhibited acetylcholinesterase (AChE). If the in vitro oxime reactivation of nerve agent-inhibited animal AChE is similar to that of human AChE, it is likely that the results of an in vivo animal study will reliably extrapolate to humans. Therefore, the goal of this study was to compare the aging and reactivation of human and different monkey (Rhesus, Cynomolgus, and African Green) AChEs inhibited by GF, GD, and VR. The oximes examined include the traditional oxime 2-PAM, two H-oximes HI-6 and HLo-7, and the new candidate oxime MMB4. Results indicate that oxime reactivation of all three monkey AChEs was very similar to human AChE. The maximum difference in the second-order reactivation rate constant between human and three monkey AChEs or between AChEs from different monkey species was 5-fold. Aging rate constants of GF-, GD-, and VR-inhibited monkey AChEs were very similar to human AChE except for GF-inhibited monkey AChEs, which aged 2-3 times faster than the human enzyme. The results of this study suggest that all three monkey species are suitable animal models for nerve agent antidote evaluation since monkey AChEs possess similar biochemical/pharmacological properties to human AChE.

Combining human and machine intelligence to derive agents' behavioral rules for groundwater irrigation

Science.gov (United States)

Hu, Yao; Quinn, Christopher J.; Cai, Ximing; Garfinkle, Noah W.

2017-11-01

For agent-based modeling, the major challenges in deriving agents' behavioral rules arise from agents' bounded rationality and data scarcity. This study proposes a "gray box" approach to address the challenge by incorporating expert domain knowledge (i.e., human intelligence) with machine learning techniques (i.e., machine intelligence). Specifically, we propose using directed information graph (DIG), boosted regression trees (BRT), and domain knowledge to infer causal factors and identify behavioral rules from data. A case study is conducted to investigate farmers' pumping behavior in the Midwest, U.S.A. Results show that four factors identified by the DIG algorithm- corn price, underlying groundwater level, monthly mean temperature and precipitation- have main causal influences on agents' decisions on monthly groundwater irrigation depth. The agent-based model is then developed based on the behavioral rules represented by three DIGs and modeled by BRTs, and coupled with a physically-based groundwater model to investigate the impacts of agents' pumping behavior on the underlying groundwater system in the context of coupled human and environmental systems.

Effects of different doses of doxycycline hyclate on haematological parameters of dogs with ehrlichiosis

Directory of Open Access Journals (Sweden)

Mariana Cristina Hoeppner Rondelli

2016-11-01

Full Text Available This study aimed to compare the effects of two doses of doxycycline hyclate on red blood cells, hemoglobin, hematocrit, white blood cells and platelets of dogs with ehrlichiosis. Group I, comprised of healthy dogs (n=6, negative on serology for Ehrlichia canis and Leptospira spp., real time PCR for E. canis and Anaplasma platys, and on semi–nested PCR for Babesia canis; Groups II (n=6 and III (n=6, comprised of dogs with suggestive clinical history, positive serology and/or real time PCR for E. canis, negative on research for anti-Leptospira spp. antibodies and real time PCR for A. platys, and on semi–nested PCR for B. canis were studied. Sick dogs were treated with doxycycline hyclate every 12 hours, by mouth, for 30 days (5 mg/kg, group II; 10 mg/kg, group III. Complete blood counts were performed before, after 15 days, and 10 days after period of treatment was complete. No difference between groups at the studied time points were noticed for red blood cells, hemoglobin, haematocrit and white blood cells. Difference was observed for platelets between group I and groups II and III (p<0.0001 at the study onset. After 15 days of treatment, the mean platelet for group III was lower than groups I (p=0.008 and II (p=0.0007, indicative of persistent thrombocytopenia, already absent in group II. No difference between groups was noticed at final time point, which suggests that both treatments increased platelets in dogs naturally infected with E. canis.

Identification of walking human model using agent-based modelling

Science.gov (United States)

Shahabpoor, Erfan; Pavic, Aleksandar; Racic, Vitomir

2018-03-01

The interaction of walking people with large vibrating structures, such as footbridges and floors, in the vertical direction is an important yet challenging phenomenon to describe mathematically. Several different models have been proposed in the literature to simulate interaction of stationary people with vibrating structures. However, the research on moving (walking) human models, explicitly identified for vibration serviceability assessment of civil structures, is still sparse. In this study, the results of a comprehensive set of FRF-based modal tests were used, in which, over a hundred test subjects walked in different group sizes and walking patterns on a test structure. An agent-based model was used to simulate discrete traffic-structure interactions. The occupied structure modal parameters found in tests were used to identify the parameters of the walking individual's single-degree-of-freedom (SDOF) mass-spring-damper model using 'reverse engineering' methodology. The analysis of the results suggested that the normal distribution with the average of μ = 2.85Hz and standard deviation of σ = 0.34Hz can describe human SDOF model natural frequency. Similarly, the normal distribution with μ = 0.295 and σ = 0.047 can describe the human model damping ratio. Compared to the previous studies, the agent-based modelling methodology proposed in this paper offers significant flexibility in simulating multi-pedestrian walking traffics, external forces and simulating different mechanisms of human-structure and human-environment interaction at the same time.

Untitled

African Journals Online (AJOL)

R. sanguinens ticks are known vectors of pathogens like Babesia aunts and Ehrlichia cents, the etiological agents of canine babesiosis and canine monocytic ehrlichiosis, respectively. Interestingly, it has been suspected that R, sanguineus is involved in the transmission of other major pathogens such as. Leishmania ...

Study of occupational risk agents and its probable hazards to human health

International Nuclear Information System (INIS)

Carneiro, Janete Cristina G. Gaburo; Alves, Alice dos Santos; Sanches, Matias P.

2013-01-01

Currently the workplaces become increasingly complex and a strategy evaluation and the control of occupational risks agents is needed. Workers may be exposed to environmental agents (chemical, physical and biological) and other unsuitable conditions by performing tasks that involve these agents directly. The main objective of this study is to approach conceptual aspects of risk conditions, physical in nature, with emphasis on ionizing radiation and its interaction with other agents in occupational and environmental situations. To meet this goal, it is performed a literature review and a summary of the main occupational agents known or suspected to cause any adverse health effects in humans. According to the available literature the reported studies on the effects of combined exposures to radiation and others agents are recognized and, as far as possible, should be taken into account in evaluating of the potential radiation risks at low levels of exposure. (author)

[EPIDEMIOLOGIC SITUATION BY NATURAL-FOCI INFECTIONS IN THE CRIMEA FEDERAL DISTRICT IN 2014-2015].

Science.gov (United States)

Popova, A-Yu; Kulichenko, A N; Maletskaya, O V; Vasilenko, N F; Shaposhnikova, L I; Kotenev, E S; Dubyansky, V M; Volynkina, A S; Lisitskaya, Ya V; Samarina, I V; Penkovskaya, N A; Evstafiev, I L; Tovpinets, N N; Tsapko, N V; Belova, O A; Agapitov, D S; Samoded, T N; Nadolny, A A; Kovalenko, I S; Yakunin, S N; Shvarsalon, N K; Zinich, L S; Tikhonov, S N; Lyamkin, G I; Zharnikova, I V; Evchenko, Yu M

2016-01-01

Analysis of epidemic manifestations of natural-foci infections (NFI), clarification of spectrum of their causative agents, determination of epizootic activity of natural foci in the Crimea Federal District (KFD). Epizootologic examination of 10 administrative districts of KDF was carried out. 291 pools (2705 specimens) of ixodes ticks and 283 samples of organs of small mammals were studied by PCRmethod for the presence of DNA/RNA of causative agents of a number of NFI. Morbidity by NFI in KFD was registered by 6 nosologies: Lyme borreliosis, Marseilles fever, leptospirosis; tularemia, intestine yersiniosis and tick-borne viral encephalitis, wherein, transmissive infections made up 91.6%. Circulation of causative agents of Crimea hemorrhagic fever, Q fever, group of tick-borne spotted fever, Lyme borreliosis, human granulocytic anaplasmosis, human monocytic ehrlichiosis, hemorrhagic fever with renal syndrome, West Nile fever, tularemia and leptospirosis was established. Due to activity of natural foci of NFI further monitoring of epidemiologic and epizootologic manifestations of these infections in the Crimea, including using genetic methods of analysis, is necessary for ensuring sanitary-epidemiologic welfare of KFD population.

A Software Environment for an Adaptive Human-Aware Software Agent Supporting Attention-Demanding Tasks

NARCIS (Netherlands)

Bosse, T.; Memon, Z.A.; Oorburg, R.; Umair, M.; Treur, J.; de Vos, M.

2011-01-01

This paper presents a software environment providing human-aware ambient support for a human performing a task that demands substantial amounts of attention. The agent obtains human attention-awareness in an adaptive manner by use of a dynamical model of human attention, gaze sensoring by an

Can human-like Bots control collective mood: agent-based simulations of online chats

Science.gov (United States)

Tadić, Bosiljka; Šuvakov, Milovan

2013-10-01

Using an agent-based modeling approach, in this paper, we study self-organized dynamics of interacting agents in the presence of chat Bots. Different Bots with tunable ‘human-like’ attributes, which exchange emotional messages with agents, are considered, and the collective emotional behavior of agents is quantitatively analyzed. In particular, using detrended fractal analysis we determine persistent fluctuations and temporal correlations in time series of agent activity and statistics of avalanches carrying emotional messages of agents when Bots favoring positive/negative affects are active. We determine the impact of Bots and identify parameters that can modulate that impact. Our analysis suggests that, by these measures, the emotional Bots induce collective emotion among interacting agents by suitably altering the fractal characteristics of the underlying stochastic process. Positive emotion Bots are slightly more effective than negative emotion Bots. Moreover, Bots which periodically alternate between positive and negative emotion can enhance fluctuations in the system, leading to avalanches of agent messages that are reminiscent of self-organized critical states.

Toward Shared Working Space of Human and Robotic Agents Through Dipole Flow Field for Dependable Path Planning.

Science.gov (United States)

Trinh, Lan Anh; Ekström, Mikael; Cürüklü, Baran

2018-01-01

Recent industrial developments in autonomous systems, or agents, which assume that humans and the agents share the same space or even work in close proximity, open for new challenges in robotics, especially in motion planning and control. In these settings, the control system should be able to provide these agents a reliable path following control when they are working in a group or in collaboration with one or several humans in complex and dynamic environments. In such scenarios, these agents are not only moving to reach their goals, i.e., locations, they are also aware of the movements of other entities to find a collision-free path. Thus, this paper proposes a dependable, i.e., safe, reliable and effective, path planning algorithm for a group of agents that share their working space with humans. Firstly, the method employs the Theta * algorithm to initialize the paths from a starting point to a goal for a set of agents. As Theta * algorithm is computationally heavy, it only reruns when there is a significant change of the environment. To deal with the movements of the agents, a static flow field along the configured path is defined. This field is used by the agents to navigate and reach their goals even if the planned trajectories are changed. Secondly, a dipole field is calculated to avoid the collision of agents with other agents and human subjects. In this approach, each agent is assumed to be a source of a magnetic dipole field in which the magnetic moment is aligned with the moving direction of the agent. The magnetic dipole-dipole interactions between these agents generate repulsive forces to help them to avoid collision. The effectiveness of the proposed approach has been evaluated with extensive simulations. The results show that the static flow field is able to drive agents to the goals with a small number of requirements to update the path of agents. Meanwhile, the dipole flow field plays an important role to prevent collisions. The combination of

Toward Shared Working Space of Human and Robotic Agents Through Dipole Flow Field for Dependable Path Planning

Directory of Open Access Journals (Sweden)

Lan Anh Trinh

2018-06-01

Full Text Available Recent industrial developments in autonomous systems, or agents, which assume that humans and the agents share the same space or even work in close proximity, open for new challenges in robotics, especially in motion planning and control. In these settings, the control system should be able to provide these agents a reliable path following control when they are working in a group or in collaboration with one or several humans in complex and dynamic environments. In such scenarios, these agents are not only moving to reach their goals, i.e., locations, they are also aware of the movements of other entities to find a collision-free path. Thus, this paper proposes a dependable, i.e., safe, reliable and effective, path planning algorithm for a group of agents that share their working space with humans. Firstly, the method employs the Theta* algorithm to initialize the paths from a starting point to a goal for a set of agents. As Theta* algorithm is computationally heavy, it only reruns when there is a significant change of the environment. To deal with the movements of the agents, a static flow field along the configured path is defined. This field is used by the agents to navigate and reach their goals even if the planned trajectories are changed. Secondly, a dipole field is calculated to avoid the collision of agents with other agents and human subjects. In this approach, each agent is assumed to be a source of a magnetic dipole field in which the magnetic moment is aligned with the moving direction of the agent. The magnetic dipole-dipole interactions between these agents generate repulsive forces to help them to avoid collision. The effectiveness of the proposed approach has been evaluated with extensive simulations. The results show that the static flow field is able to drive agents to the goals with a small number of requirements to update the path of agents. Meanwhile, the dipole flow field plays an important role to prevent collisions. The

Recent progress in econophysics: Chaos, leverage, and business cycles as revealed by agent-based modeling and human experiments

Science.gov (United States)

Xin, Chen; Huang, Ji-Ping

2017-12-01

Agent-based modeling and controlled human experiments serve as two fundamental research methods in the field of econophysics. Agent-based modeling has been in development for over 20 years, but how to design virtual agents with high levels of human-like "intelligence" remains a challenge. On the other hand, experimental econophysics is an emerging field; however, there is a lack of experience and paradigms related to the field. Here, we review some of the most recent research results obtained through the use of these two methods concerning financial problems such as chaos, leverage, and business cycles. We also review the principles behind assessments of agents' intelligence levels, and some relevant designs for human experiments. The main theme of this review is to show that by combining theory, agent-based modeling, and controlled human experiments, one can garner more reliable and credible results on account of a better verification of theory; accordingly, this way, a wider range of economic and financial problems and phenomena can be studied.

Recent progress in econophysics: Chaos, leverage,and business cycles as revealed by agent-based modeling and human experiments

Institute of Scientific and Technical Information of China (English)

Chen Xin; Ji-Ping Huang

2017-01-01

Agent-based modeling and controlled human experiments serve as two fundamental research methods in the field of econophysics.Agent-based modeling has been in development for over 20 years,but how to design virtual agents with high levels of human-like "intelligence" remains a challenge.On the other hand,experimental econophysics is an emerging field;however,there is a lack of experience and paradigms related to the field.Here,we review some of the most recent research results obtained through the use of these two methods concerning financial problems such as chaos,leverage,and business cycles.We also review the principles behind assessments of agents' intelligence levels,and some relevant designs for human experiments.The main theme of this review is to show that by combining theory,agent-based modeling,and controlled human experiments,one can garner more reliable and credible results on account of a better verification of theory;accordingly,this way,a wider range of economic and financial problems and phenomena can be studied.

Traitement de l'hétérogénéité sémantique dans les interactions humain-agent et agent-agent

OpenAIRE

Mazuel , Laurent

2008-01-01

The main purpose of this thesis is the management of semantic heterogeneity in human-agent and agent-agent interaction. We especially focus on the situation where a software agent, supplied with a knowledge representation model, has to understand requests coming from different interlocutors; either it is a human user or another software agent.Most work in this domain either focus on human-agent interaction or agent-agent interaction. On the contrary, we suggest that it is possible to use a co...

Can human-like Bots control collective mood: agent-based simulations of online chats

International Nuclear Information System (INIS)

Tadić, Bosiljka; Šuvakov, Milovan

2013-01-01

Using an agent-based modeling approach, in this paper, we study self-organized dynamics of interacting agents in the presence of chat Bots. Different Bots with tunable ‘human-like’ attributes, which exchange emotional messages with agents, are considered, and the collective emotional behavior of agents is quantitatively analyzed. In particular, using detrended fractal analysis we determine persistent fluctuations and temporal correlations in time series of agent activity and statistics of avalanches carrying emotional messages of agents when Bots favoring positive/negative affects are active. We determine the impact of Bots and identify parameters that can modulate that impact. Our analysis suggests that, by these measures, the emotional Bots induce collective emotion among interacting agents by suitably altering the fractal characteristics of the underlying stochastic process. Positive emotion Bots are slightly more effective than negative emotion Bots. Moreover, Bots which periodically alternate between positive and negative emotion can enhance fluctuations in the system, leading to avalanches of agent messages that are reminiscent of self-organized critical states. (paper)

Gadolinium-based magnetic resonance contrast agents at 7 Tesla: in vitro T1 relaxivities in human blood plasma.

Science.gov (United States)

Noebauer-Huhmann, Iris M; Szomolanyi, Pavol; Juras, Vladimír; Kraff, Oliver; Ladd, Mark E; Trattnig, Siegfried

2010-09-01

PURPOSE/INTRODUCTION: The aim of this study was to determine the T1 relaxivities (r1) of 8 gadolinium (Gd)-based MR contrast agents in human blood plasma at 7 Tesla, compared with 3 Tesla. Eight commercially available Gd-based MR contrast agents were diluted in human blood plasma to concentrations of 0, 0.25, 0.5, 1, and 2 mmol/L. In vitro measurements were performed at 37 degrees C, on a 7 Tesla and on a 3 Tesla whole-body magnetic resonance imaging scanner. For the determination of T1 relaxation times, Inversion Recovery Sequences with inversion times from 0 to 3500 ms were used. The relaxivities were calculated. The r1 relaxivities of all agents, diluted in human blood plasma at body temperature, were lower at 7 Tesla than at 3 Tesla. The values at 3 Tesla were comparable to those published earlier. Notably, in some agents, a minor negative correlation of r1 with a concentration of up to 2 mmol/L could be observed. This was most pronounced in the agents with the highest protein-binding capacity. At 7 Tesla, the in vitro r1 relaxivities of Gd-based contrast agents in human blood plasma are lower than those at 3 Tesla. This work may serve as a basis for the application of Gd-based MR contrast agents at 7 Tesla. Further studies are required to optimize the contrast agent dose in vivo.

Analysis of cytotoxic effects of chlorhexidine gluconate as antiseptic agent on human blood lymphocytes.

Science.gov (United States)

Salimi, Ahmad; Alami, Bahare; Pourahmad, Jalal

2017-08-01

The aim of this study was to assess the cytotoxicity of chlorhexidine gluconate (CHG) on human blood lymphocytes as a useful ex vivo model for accelerated human toxicity studies. Using biochemical and flow cytometry assessments, we demonstrated that addition of CHG at 1 μM concentration to human blood lymphocytes induced cytotoxicity following 6 h. The CHG-induced cytotoxicity on human blood lymphocytes was associated with intracellular reactive oxygen species generation, mitochondrial membrane potential collapse, lysosomal membrane injury, lipid peroxidation, and depletion of glutathione. According to our results, CHG triggers oxidative stress and organelles damages in lymphocytes which are important cells in defense against foreign agents. Finally our findings suggest that using of antioxidants and mitochondrial/lysosomal protective agents could be of benefit for the people in the exposure with CHG. © 2017 Wiley Periodicals, Inc.

[Unconventional disease agents--a danger for humans and animals?].

Science.gov (United States)

Kaaden, O R

1994-02-01

The occurrence of bovine spongiform encephalopathy (BSE) in Great Britain in 1985/86, has focused again the public concern as well as scientific interest to the Scrapie disease of sheep and goat known more than 150 years. The agents of scrapie and BSE are characterized by unusual biological and physical-chemical properties, especially their high tenacity. Therefore, they are also designated "unconventional agents of viruses". Different theories have been proposed about their infectious characteristics--especially because of the apparent or real missing of an agent-specific nucleic acid--which are named Virinos, Prions or Nemavirus. The broad host range of Scrapie respective BSE, which includes domestic and wild ruminants, Suidae, Felidae, Mustelidae, small rodents, birds and non-primates, has created some concern since there might be an aetiological correlation between the transmissible spongiform encephalopathies of man (Creutzfeld-Jakob- and Gerstmann-Sträussler-Scheinker-Disease) and that of animals. Although at present neither epidemiological nor molecular biological evidence whatsoever was proved, the hypothesis cannot be completely disproved. The probability of infection through digestive tract seems to be rather unlikely but special precautions should be taken as far as production, investigation and application of human medicine drugs of animal origin. Furthermore, research about the aetiology of "unconventional agents" and pathogenesis of resulting diseases is necessary and should be intensified in Germany. Finally, only an early intra vitam-Diagnose and in vitro detection can avoid an further spread of this new category of diseases.

Military chemical warfare agent human subjects testing: part 1--history of six-decades of military experiments with chemical warfare agents.

Science.gov (United States)

Brown, Mark

2009-10-01

Military chemical warfare agent testing from World War I to 1975 produced thousands of veterans with concerns of possible long-term health consequences. Clinical and research evaluation of potential long-term health effects has been difficult because the exposures occurred decades ago, the identity of troops exposed and exposure magnitudes are uncertain, and acute effects during experiments poorly documented. In contrast, a companion article describes the large amount of information available about the specific agents tested and their long-term health effects. This short history describes U.S. military chemical-agent experiments with human subjects and identifies tested agents. Finally, the demonstrated need to anticipate future health concerns from military personnel involved in such military testing suggests current and future military researchers should be required, by law and regulation, to fully record the identity of those exposed, relevant exposure magnitude, and complete medical information for all subjects. New study protocols and institutional review board approvals for research involving military personnel should reflect this need.

A conceptual and computational model of moral decision making in human and artificial agents.

Science.gov (United States)

Wallach, Wendell; Franklin, Stan; Allen, Colin

2010-07-01

Recently, there has been a resurgence of interest in general, comprehensive models of human cognition. Such models aim to explain higher-order cognitive faculties, such as deliberation and planning. Given a computational representation, the validity of these models can be tested in computer simulations such as software agents or embodied robots. The push to implement computational models of this kind has created the field of artificial general intelligence (AGI). Moral decision making is arguably one of the most challenging tasks for computational approaches to higher-order cognition. The need for increasingly autonomous artificial agents to factor moral considerations into their choices and actions has given rise to another new field of inquiry variously known as Machine Morality, Machine Ethics, Roboethics, or Friendly AI. In this study, we discuss how LIDA, an AGI model of human cognition, can be adapted to model both affective and rational features of moral decision making. Using the LIDA model, we will demonstrate how moral decisions can be made in many domains using the same mechanisms that enable general decision making. Comprehensive models of human cognition typically aim for compatibility with recent research in the cognitive and neural sciences. Global workspace theory, proposed by the neuropsychologist Bernard Baars (1988), is a highly regarded model of human cognition that is currently being computationally instantiated in several software implementations. LIDA (Franklin, Baars, Ramamurthy, & Ventura, 2005) is one such computational implementation. LIDA is both a set of computational tools and an underlying model of human cognition, which provides mechanisms that are capable of explaining how an agent's selection of its next action arises from bottom-up collection of sensory data and top-down processes for making sense of its current situation. We will describe how the LIDA model helps integrate emotions into the human decision-making process, and we

Effects of treatment with antimicrobial agents on the human colonic microflora

Directory of Open Access Journals (Sweden)

Fatemeh Rafii

2008-12-01

Full Text Available Fatemeh Rafii, John B Sutherland, Carl E CernigliaDivision of Microbiology, National Center for Toxicological Research, FDA, Jefferson, AR, USAAbstract: Antimicrobial agents are the most valuable means available for treating bacterial infections. However, the administration of therapeutic doses of antimicrobial agents to patients is a leading cause of disturbance of the normal gastrointestinal microflora. This disturbance results in diminishing the natural defense mechanisms provided by the colonic microbial ecosystem, making the host vulnerable to infection by commensal microorganisms or nosocomial pathogens. In this minireview, the impacts of antimicrobials, individually and in combinations, on the human colonic microflora are discussed.Keywords: antibiotics, intestinal bacteria

You Look Human, But Act Like a Machine: Agent Appearance and Behavior Modulate Different Aspects of Human–Robot Interaction

Directory of Open Access Journals (Sweden)

Abdulaziz Abubshait

2017-08-01

Full Text Available Gaze following occurs automatically in social interactions, but the degree to which gaze is followed depends on whether an agent is perceived to have a mind, making its behavior socially more relevant for the interaction. Mind perception also modulates the attitudes we have toward others, and determines the degree of empathy, prosociality, and morality invested in social interactions. Seeing mind in others is not exclusive to human agents, but mind can also be ascribed to non-human agents like robots, as long as their appearance and/or behavior allows them to be perceived as intentional beings. Previous studies have shown that human appearance and reliable behavior induce mind perception to robot agents, and positively affect attitudes and performance in human–robot interaction. What has not been investigated so far is whether different triggers of mind perception have an independent or interactive effect on attitudes and performance in human–robot interaction. We examine this question by manipulating agent appearance (human vs. robot and behavior (reliable vs. random within the same paradigm and examine how congruent (human/reliable vs. robot/random versus incongruent (human/random vs. robot/reliable combinations of these triggers affect performance (i.e., gaze following and attitudes (i.e., agent ratings in human–robot interaction. The results show that both appearance and behavior affect human–robot interaction but that the two triggers seem to operate in isolation, with appearance more strongly impacting attitudes, and behavior more strongly affecting performance. The implications of these findings for human–robot interaction are discussed.

Users, Bystanders and Agents

DEFF Research Database (Denmark)

Krummheuer, Antonia Lina

2015-01-01

Human-agent interaction (HAI), especially in the field of embodied conversational agents (ECA), is mainly construed as dyadic communication between a human user and a virtual agent. This is despite the fact that many application scenarios for future ECAs involve the presence of others. This paper...

HoldemML: A framework to generate No Limit Hold'em Poker agents from human player strategies

OpenAIRE

Luís Filipe Teófilo; Luís Paulo Reis

2011-01-01

Developing computer programs that play Poker at human level is considered to be challenge to the A.I research community, due to its incomplete information and stochastic nature. Due to these characteristics of the game, a competitive agent must manage luck and use opponent modeling to be successful at short term and therefore be profitable. In this paper we propose the creation of No Limit Hold'em Poker agents by copying strategies of the best human players, by analyzing past games between th...

Agent-based simulation for human-induced hazard analysis.

Science.gov (United States)

Bulleit, William M; Drewek, Matthew W

2011-02-01

Terrorism could be treated as a hazard for design purposes. For instance, the terrorist hazard could be analyzed in a manner similar to the way that seismic hazard is handled. No matter how terrorism is dealt with in the design of systems, the need for predictions of the frequency and magnitude of the hazard will be required. And, if the human-induced hazard is to be designed for in a manner analogous to natural hazards, then the predictions should be probabilistic in nature. The model described in this article is a prototype model that used agent-based modeling (ABM) to analyze terrorist attacks. The basic approach in this article of using ABM to model human-induced hazards has been preliminarily validated in the sense that the attack magnitudes seem to be power-law distributed and attacks occur mostly in regions where high levels of wealth pass through, such as transit routes and markets. The model developed in this study indicates that ABM is a viable approach to modeling socioeconomic-based infrastructure systems for engineering design to deal with human-induced hazards. © 2010 Society for Risk Analysis.

You Look Human, But Act Like a Machine: Agent Appearance and Behavior Modulate Different Aspects of Human–Robot Interaction

OpenAIRE

Abubshait, Abdulaziz; Wiese, Eva

2017-01-01

Gaze following occurs automatically in social interactions, but the degree to which gaze is followed depends on whether an agent is perceived to have a mind, making its behavior socially more relevant for the interaction. Mind perception also modulates the attitudes we have toward others, and determines the degree of empathy, prosociality, and morality invested in social interactions. Seeing mind in others is not exclusive to human agents, but mind can also be ascribed to non-human agents lik...

Autonomous Agents on Expedition: Humans and Progenitor Ants and Planetary Exploration

Science.gov (United States)

Rilee, M. L.; Clark, P. E.; Curtis, S. A.; Truszkowski, W. F.

2002-01-01

The Autonomous Nano-Technology Swarm (ANTS) is an advanced mission architecture based on a social insect analog of many specialized spacecraft working together to achieve mission goals. The principal mission concept driving the ANTS architecture is a Main Belt Asteroid Survey in the 2020s that will involve a thousand or more nano-technology enabled, artificially intelligent, autonomous pico-spacecraft (architecture. High level, mission-oriented behaviors are to be managed by a control / communications layer of the swarm, whereas common low level functions required of all spacecraft, e.g. attitude control and guidance and navigation, are handled autonomically on each spacecraft. At the higher levels of mission planning and social interaction deliberative techniques are to be used. For the asteroid survey, ANTS acts as a large community of cooperative agents while for precursor missions there arises the intriguing possibility of Progenitor ANTS and humans acting together as agents. For optimal efficiency and responsiveness for individual spacecraft at the lowest levels of control we have been studying control methods based on nonlinear dynamical systems. We describe the critically important autonomous control architecture of the ANTS mission concept and a sequence of partial implementations that feature increasingly autonomous behaviors. The scientific and engineering roles that these Progenitor ANTS could play in human missions or remote missions with near real time human interactions, particularly to the Moon and Mars, will be discussed.

Effects of antineoplastic agents and ionizing irradiation on a human testicular cancer xenograft

International Nuclear Information System (INIS)

Osieka, R.; Pfeiffer, R.; Glatte, P.; Schmidt, C.G.; Bamberg, M.; Scherer, E.

1985-01-01

Chemotherapy has afforded a high percentage of definitive cures in advanced testicular cancer. Nevertheless some patients with large tumor burden still succumb to chemorefractory disease. Therefore preclinical and clinical evaluation of new drugs and agents not primarily used against this type of disease are still mandatory. For preclinical drug screening purposes heterotransplantation of specific human tumors yields a model with high validity for tumor markers and drug response. Heterotransplantation of a human embryonal testicular cancer was used for simultaneous testing of established agents such as cisplatin, melphalan, bleomycin, vinblastine, etoposide and adriamycin and some newer derivatives such as PHM or mafosfamide. Furthermore agents such as procarbazine, dacarbazine and methyl-CCNU that cross the blood-brain-barrier displayed some interesting activity. The results hint at a unique chemosensitivity pattern of the xenograft line, with some accordance between clinical response to vinblastine and bleomycin and good response of the xenografts to bleomycin but not to vinblastine. Radiotherapy was also effective against this tumor line, but there was not much difference in response when the schedule of fractionation was changed. It is concluded that a combined modality approach might salvage patients with residual, chemorefractory disease. (orig.) [de

Temporal and Spatial Distribution of Tick-Borne Disease Cases among Humans and Canines in Illinois (2000-2009

Directory of Open Access Journals (Sweden)

John A. Herrmann

2014-01-01

Full Text Available Four tick-borne diseases (TBDs, anaplasmosis, ehrlichiosis, Lyme disease (LD, and Rocky Mountain spotted fever (RMSF, are endemic in Illinois. The prevalence of human and canine cases of all four TBDs rose over the study period with significant differences in geographic distribution within the state. Among human cases, there were associations between cases of RMSF and LD and total forest cover, seasonal precipitation, average mean temperature, racial-ethnic groups, and gender. Estimated annual prevalence of three canine TBDs exceeded human TBD cases significantly in each region. There was concordance in the number of human and canine cases by county of residence, in annual prevalence trends, and in time of year at which they were diagnosed. To account for multiple environmental risk factors and to facilitate early diagnosis of cases, integrated surveillance systems must be developed and communication between veterinarians, physicians, and public health agencies must be improved.

Activation of the human immune system by chemotherapeutic or targeted agents combined with the oncolytic parvovirus H-1

International Nuclear Information System (INIS)

Moehler, Markus; Sieben, Maike; Roth, Susanne; Springsguth, Franziska; Leuchs, Barbara; Zeidler, Maja; Dinsart, Christiane; Rommelaere, Jean; Galle, Peter R

2011-01-01

Parvovirus H-1 (H-1PV) infects and lyses human tumor cells including melanoma, hepatoma, gastric, colorectal, cervix and pancreatic cancers. We assessed whether the beneficial effects of chemotherapeutic agents or targeted agents could be combined with the oncolytic and immunostimmulatory properties of H-1PV. Using human ex vivo models we evaluated the biological and immunological effects of H-1PV-induced tumor cell lysis alone or in combination with chemotherapeutic or targeted agents in human melanoma cells +/- characterized human cytotoxic T-cells (CTL) and HLA-A2-restricted dendritic cells (DC). H-1PV-infected MZ7-Mel cells showed a clear reduction in cell viability of >50%, which appeared to occur primarily through apoptosis. This correlated with viral NS1 expression levels and was enhanced by combination with chemotherapeutic agents or sunitinib. Tumor cell preparations were phagocytosed by DC whose maturation was measured according to the treatment administered. Immature DC incubated with H-1PV-induced MZ7-Mel lysates significantly increased DC maturation compared with non-infected or necrotic MZ7-Mel cells. Tumor necrosis factor-α and interleukin-6 release was clearly increased by DC incubated with H-1PV-induced SK29-Mel tumor cell lysates (TCL) and was also high with DC-CTL co-cultures incubated with H-1PV-induced TCL. Similarly, DC co-cultures with TCL incubated with H-1PV combined with cytotoxic agents or sunitinib enhanced DC maturation to a greater extent than cytotoxic agents or sunitinib alone. Again, these combinations increased pro-inflammatory responses in DC-CTL co-cultures compared with chemotherapy or sunitinib alone. In our human models, chemotherapeutic or targeted agents did not only interfere with the pronounced immunomodulatory properties of H-1PV, but also reinforced drug-induced tumor cell killing. H-1PV combined with cisplatin, vincristine or sunitinib induced effective immunostimulation via a pronounced DC maturation, better cytokine

Study of occupational risk agents and its probable hazards to human health; Estudo dos agentes de risco ocupacional e seus provaveis agravos na saude humana

Energy Technology Data Exchange (ETDEWEB)

Carneiro, Janete Cristina G. Gaburo; Alves, Alice dos Santos; Sanches, Matias P., E-mail: janetegc@ipen.br, E-mail: alicesante@hotmail.com, E-mail: msanches@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

2013-07-01

Currently the workplaces become increasingly complex and a strategy evaluation and the control of occupational risks agents is needed. Workers may be exposed to environmental agents (chemical, physical and biological) and other unsuitable conditions by performing tasks that involve these agents directly. The main objective of this study is to approach conceptual aspects of risk conditions, physical in nature, with emphasis on ionizing radiation and its interaction with other agents in occupational and environmental situations. To meet this goal, it is performed a literature review and a summary of the main occupational agents known or suspected to cause any adverse health effects in humans. According to the available literature the reported studies on the effects of combined exposures to radiation and others agents are recognized and, as far as possible, should be taken into account in evaluating of the potential radiation risks at low levels of exposure. (author)

Reactions of human dental pulp cells to capping agents in the presence or absence of bacterial exposure.

Science.gov (United States)

Cai, Shiwei; Zhang, Wenjian; Tribble, Gena; Chen, Wei

2017-01-01

An ideal pulp-capping agent needs to have good biocompatibility and promote reparative dentinogenesis. Although the effects of capping agents on healthy pulp are known, limited data regarding their effects on bacterial contaminated pulp are available. This study aimed to evaluate the reaction of contaminated pulps to various capping agents to assist clinicians in making informed decisions. Human dental pulp (HDP) cell cultures were developed from extracted human molars. The cells were exposed to a bacterial cocktail comprising Porphyromonas gingivalis, Prevotella intermedia, and Streptococcus gordonii before being cocultured with capping agents such as mineral trioxide aggregate (MTA) Portland cement (PC), and Dycal. HDP cell proliferation was assayed by MTS colorimetric cell proliferation assay, and its differentiation was evaluated by real-time PCR for detecting alkaline phosphatase, dentin sialophosphoprotein, and osteocalcin expressions. MTA and PC had no apparent effect, whereas Dycal inhibited HDP cell proliferation. PC stimulated HDP cell differentiation, particularly when they were exposed to bacteria. MTA and Dycal inhibited differentiation, regardless of bacterial infection. In conclusion, PC was the most favorable agent, followed by MTA, and Dycal was the least favorable agent for supporting the functions of bacterial compromised pulp cells.

Theoretical foundations of human decision-making in agent-based land use models – A review

NARCIS (Netherlands)

Groeneveld, Geert J.; Müller, B.; Buchmann, C.M.; Dressler, Gunnar; Guo, C.; Hase, N.; Hoffmann, F.; John, F.; Klassert, C.; Lauf, T.; Liebelt, V.; Nolzen, H.; Pannicke, N.; Schulze, J.; Weise, H.; Schwarz, N.

2017-01-01

Recent reviews stated that the complex and context-dependent nature of human decision-making resulted in ad-hoc representations of human decision in agent-based land use change models (LUCC ABMs) and that these representations are often not explicitly grounded in theory. However, a systematic survey

Applying tattoo dye as a third-harmonic generation contrast agent for in vivo optical virtual biopsy of human skin

Science.gov (United States)

Tsai, Ming-Rung; Lin, Chen-Yu; Liao, Yi-Hua; Sun, Chi-Kuang

2013-02-01

Third-harmonic generation (THG) microscopy has been reported to provide intrinsic contrast in elastic fibers, cytoplasmic membrane, nucleus, actin filaments, lipid bodies, hemoglobin, and melanin in human skin. For advanced molecular imaging, exogenous contrast agents are developed for a higher structural or molecular specificity. We demonstrate the potential of the commonly adopted tattoo dye as a THG contrast agent for in vivo optical biopsy of human skin. Spectroscopy and microscopy experiments were performed on cultured cells with tattoo dyes, in tattooed mouse skin, and in tattooed human skin to demonstrate the THG enhancement effect. Compared with other absorbing dyes or nanoparticles used as exogenous THG contrast agents, tattoo dyes are widely adopted in human skin so that future clinical biocompatibility evaluation is relatively achievable. Combined with the demonstrated THG enhancement effect, tattoo dyes show their promise for future clinical imaging applications.

Agent Orange Exposure and 2,3,7,8-Tetrachlorodibenzo-p-Dioxin (TCDD) in Human Milk.

Science.gov (United States)

Scialli, Anthony R; Watkins, Deborah K; Ginevan, Michael E

2015-06-01

Agent Orange was sprayed in parts of southern Vietnam during the U.S.-Vietnam war and was a mixture of two chlorophenoxy herbicides. The mixture was contaminated with 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). TCDD and other dioxins and furans are measurable in the milk of Vietnamese women. We explored whether the TCDD in milk from these women was from Agent Orange and whether lactational exposure can be a mode of transgenerational effects of TCDD from Agent Orange. A review of the world's literature on milk concentrations of polychlorinated compounds showed the presence of TCDD and other dioxins and furans in all countries that have been assessed. The congener profile of these chemicals, that is, the proportion of different congeners in the sample, can be used to assess the source of milk contamination. Measurements in most countries, including contemporary measurements in Vietnam, are consistent with non-Agent Orange exposure sources, including industrial activities and incineration of waste. Models and supporting human data suggest that TCDD from breastfeeding does not persist in a child past adolescence and that the adult body burden of TCDD is independent of whether the individual was breast- or bottle-fed as a child. These findings suggest that exposure to Agent Orange in Vietnam did not result in persistent transgenerational exposure through human milk. © 2015 Wiley Periodicals, Inc.

Serologic evidence of infection with granulocytic ehrlichiae in black bears in Pennsylvania.

Science.gov (United States)

Schultz, Sharon M; Nicholson, William L; Comer, James A; Childs, James E; Humphreys, Jan G

2002-01-01

Serum samples from 381 black bears (Ursus americanus) killed in Pennsylvania (USA) on 24 November 1997 were analyzed for antibodies reactive to the agent of human granulocytic ehrlichiosis (HGE; Ehrlichia sp.) by indirect immunofluorescence assay. Antibody reactivity to HGE antigen was detected in 21% (81/381) of the samples collected. Reactive samples were reported from 56% (14/25) of the counties where bear samples were collected. Endpoint antibody titer ranged from 1:8 to 1:16, 192, with a geometric mean titer of 1:582. There was no significant difference in antibody prevalence between male and female bears (P bears were significantly more likely to have reactive antibodies than juvenile bears (P bear blood clots (n = 181) through nested polymerase chain reaction assays were unsuccessful. Further studies are needed for identification of the pathogen-responsible for induction of HGE-reactive. This is the first description of antibodies reactive to the HGE agent in black bears and suggests these mammals are infected with the agent of HGE or an antigenically related ehrlichial species.

RSDL decontamination of human skin contaminated with the nerve agent VX.

Science.gov (United States)

Thors, L; Lindberg, S; Johansson, S; Koch, B; Koch, M; Hägglund, L; Bucht, A

2017-03-05

Dermal exposure to low volatile organophosphorus compounds (OPC) may lead to penetration through the skin and uptake in the blood circulation. Skin decontamination of toxic OPCs, such as pesticides and chemical warfare nerve agents, might therefore be crucial for mitigating the systemic toxicity following dermal exposure. Reactive skin decontamination lotion (RSDL) has been shown to reduce toxic effects in animals dermally exposed to the nerve agent VX. In the present study, an in vitro flow-through diffusion cell was utilized to evaluate the efficacy of RSDL for decontamination of VX exposed to human epidermis. In particular, the impact of timing in the initiation of decontamination and agent dilution in water was studied. The impact of the lipophilic properties of VX in the RSDL decontamination was additionally addressed by comparing chemical degradation in RSDL and decontamination efficacy between the VX and the hydrophilic OPC triethyl phosphonoacetate (TEPA). The epidermal membrane was exposed to 20, 75 or 90% OPC diluted in deionized water and the decontamination was initiated 5, 10, 30, 60 or 120min post-exposure. Early decontamination of VX with RSDL, initiated 5-10min after skin exposure, was very effective. Delayed decontamination initiated 30-60min post-exposure was less effective but still the amount of penetrated agent was significantly reduced, while further delayed start of decontamination to 120min resulted in very low efficacy. Comparing RSDL decontamination of VX with that of TEPA showed that the decontamination efficacy at high agent concentrations was higher for VX. The degradation mechanism of VX and TEPA during decontamination was dissected by 31 P NMR spectroscopy of the OPCs following reactions with RSDL and its three nucleophile components. The degradation rate was clearly associated with the high pH of the specific solution investigated; i.e. increased pH resulted in a more rapid degradation. In addition, the solubility of the OPC in RSDL

Episodic memory for human-like agents and human-like agents for episodic memory

Czech Academy of Sciences Publication Activity Database

Brom, C.; Lukavský, Jiří; Kadlec, R.

2010-01-01

Roč. 2, č. 2 (2010), s. 227-244 ISSN 1793-8473 Institutional research plan: CEZ:AV0Z70250504 Keywords : episodic memory * virtual agent * modelling Subject RIV: AN - Psychology http://www.worldscinet.com/ijmc/02/0202/S1793843010000461.html

ModelforAnalyzing Human Communication Network Based onAgent-Based Simulation

Science.gov (United States)

Matsuyama, Shinako; Terano, Takao

This paper discusses dynamic properties of human communications networks, which appears as a result of informationexchanges among people. We propose agent-based simulation (ABS) to examine implicit mechanisms behind the dynamics. The ABS enables us to reveal the characteristics and the differences of the networks regarding the specific communicationgroups. We perform experiments on the ABS with activity data from questionnaires survey and with virtual data which isdifferent from the activity data. We compare the difference between them and show the effectiveness of the ABS through theexperiments.

Inhibitory Effects of Trapping Agents of Sulfur Drug Reactive Intermediates against Major Human Cytochrome P450 Isoforms

Directory of Open Access Journals (Sweden)

Jasleen K. Sodhi

2017-07-01

Full Text Available In some cases, the formation of reactive species from the metabolism of xenobiotics has been linked to toxicity and therefore it is imperative to detect potential bioactivation for candidate drugs during drug discovery. Reactive species can covalently bind to trapping agents in in vitro incubations of compound with human liver microsomes (HLM fortified with β-nicotinamide adenine dinucleotide phosphate (NADPH, resulting in a stable conjugate of trapping agent and reactive species, thereby facilitating analytical detection and providing evidence of short-lived reactive metabolites. Since reactive metabolites are typically generated by cytochrome P450 (CYP oxidation, it is important to ensure high concentrations of trapping agents are not inhibiting the activities of CYP isoforms. Here we assessed the inhibitory properties of fourteen trapping agents against the major human CYP isoforms (CYP1A2, 2C9, 2C19, 2D6 and 3A. Based on our findings, eleven trapping agents displayed inhibition, three of which had IC50 values less than 1 mM (2-mercaptoethanol, N-methylmaleimide and N-ethylmaleimide (NEM. Three trapping agents (dimedone, N-acetyl-lysine and arsenite did not inhibit CYP isoforms at concentrations tested. To illustrate effects of CYP inhibition by trapping agents on reactive intermediate trapping, an example drug (ticlopidine and trapping agent (NEM were chosen for further studies. For the same amount of ticlopidine (1 μM, increasing concentrations of the trapping agent NEM (0.007–40 mM resulted in a bell-shaped response curve of NEM-trapped ticlopidine S-oxide (TSO-NEM, due to CYP inhibition by NEM. Thus, trapping studies should be designed to include several concentrations of trapping agent to ensure optimal trapping of reactive metabolites.

21 CFR 181.28 - Release agents.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Release agents. 181.28 Section 181.28 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN... Release agents. Substances classified as release agents, when migrating from food-packaging material shall...

Generative Agents for Player Decision Modeling in Games

DEFF Research Database (Denmark)

Holmgård, Christoffer; Liapis, Antonios; Togelius, Julian

2014-01-01

This paper presents a method for modeling player decision making through the use of agents as AI-driven personas. The paper argues that artificial agents, as generative player models, have properties that allow them to be used as psyhometrically valid, abstract simulations of a human player......’s internal decision making processes. Such agents can then be used to interpret human decision making, as personas and playtesting tools in the game design process, as baselines for adapting agents to mimic classes of human players, or as believable, human-like opponents. This argument is explored...... in a crowdsourced decision making experiment, in which the decisions of human players are recorded in a small-scale dungeon themed puzzle game. Human decisions are compared to the decisions of a number of a priori defined “archetypical” agent-personas, and the humans are characterized by their likeness...

Down-regulation of DNA mismatch repair proteins in human and murine tumor spheroids: implications for multicellular resistance to alkylating agents.

Science.gov (United States)

Francia, Giulio; Green, Shane K; Bocci, Guido; Man, Shan; Emmenegger, Urban; Ebos, John M L; Weinerman, Adina; Shaked, Yuval; Kerbel, Robert S

2005-10-01

Similar to other anticancer agents, intrinsic or acquired resistance to DNA-damaging chemotherapeutics is a major obstacle for cancer therapy. Current strategies aimed at overcoming this problem are mostly based on the premise that tumor cells acquire heritable genetic mutations that contribute to drug resistance. Here, we present evidence for an epigenetic, tumor cell adhesion-mediated, and reversible form of drug resistance that is associated with a reduction of DNA mismatch repair proteins PMS2 and/or MLH1 as well as other members of this DNA repair process. Growth of human breast cancer, human melanoma, and murine EMT-6 breast cancer cell lines as multicellular spheroids in vitro, which is associated with increased resistance to many chemotherapeutic drugs, including alkylating agents, is shown to lead to a reproducible down-regulation of PMS2, MLH1, or, in some cases, both as well as MHS6, MSH3, and MSH2. The observed down-regulation is in part reversible by treatment of tumor spheroids with the DNA-demethylating agent, 5-azacytidine. Thus, treatment of EMT-6 mouse mammary carcinoma spheroids with 5-azacytidine resulted in reduced and/or disrupted cell-cell adhesion, which in turn sensitized tumor spheroids to cisplatin-mediated killing in vitro. Our results suggest that antiadhesive agents might sensitize tumor spheroids to alkylating agents in part by reversing or preventing reduced DNA mismatch repair activity and that the chemosensitization properties of 5-azacytidine may conceivably reflect its role as a potential antiadhesive agent as well as reversal agent for MLH1 gene silencing in human tumors.

Molecular Epidemiology of Agents of Human Chromoblastomycosis in Brazil with the Description of Two Novel Species.

Directory of Open Access Journals (Sweden)

Renata R Gomes

2016-11-01

Full Text Available The human mutilating disease chromoblastomycosis is caused by melanized members of the order Chaetothyriales. To assess population diversity among 123 clinical strains of agents of the disease in Brazil we applied sequencing of the rDNA internal transcribed spacer region, and partial cell division cycle and β-tubulin genes. Strains studied were limited to three clusters divided over the single family Herpotrichiellaceae known to comprise agents of the disease. A Fonsecaea cluster contained the most important agents, among which F. pedrosoi was prevalent with 80% of the total set of strains, followed by 13% for F. monophora, 3% for F. nubica, and a single isolate of F. pugnacius. Additional agents, among which two novel species, were located among members of the genus Rhinocladiella and Cyphellophora, with frequencies of 3% and 1%, respectively.

Human-Agent Decision-making: Combining Theory and Practice

Directory of Open Access Journals (Sweden)

Sarit Kraus

2016-06-01

Full Text Available Extensive work has been conducted both in game theory and logic to model strategic interaction. An important question is whether we can use these theories to design agents for interacting with people? On the one hand, they provide a formal design specification for agent strategies. On the other hand, people do not necessarily adhere to playing in accordance with these strategies, and their behavior is affected by a multitude of social and psychological factors. In this paper we will consider the question of whether strategies implied by theories of strategic behavior can be used by automated agents that interact proficiently with people. We will focus on automated agents that we built that need to interact with people in two negotiation settings: bargaining and deliberation. For bargaining we will study game-theory based equilibrium agents and for argumentation we will discuss logic-based argumentation theory. We will also consider security games and persuasion games and will discuss the benefits of using equilibrium based agents.

A Multi-Agent Environment for Negotiation

Science.gov (United States)

Hindriks, Koen V.; Jonker, Catholijn M.; Tykhonov, Dmytro

In this chapter we introduce the System for Analysis of Multi-Issue Negotiation (SAMIN). SAMIN offers a negotiation environment that supports and facilitates the setup of various negotiation setups. The environment has been designed to analyse negotiation processes between human negotiators, between human and software agents, and between software agents. It offers a range of different agents, different domains, and other options useful to define a negotiation setup. The environment has been used to test and evaluate a range of negotiation strategies in various domains playing against other negotiating agents as well as humans. We discuss some of the results obtained by means of these experiments.

Gold Nanoparticles: An Efficient Antimicrobial Agent against Enteric Bacterial Human Pathogen

Directory of Open Access Journals (Sweden)

Shahzadi Shamaila

2016-04-01

Full Text Available Enteric bacterial human pathogens, i.e., Escherichia coli, Staphylococcus aureus, Bacillus subtilis and Klebsiella pneumoniae, are the major cause of diarrheal infections in children and adults. Their structure badly affects the human immune system. It is important to explore new antibacterial agents instead of antibiotics for treatment. This project is an attempt to explain how gold nanoparticles affect these bacteria. We investigated the important role of the mean particle size, and the inhibition of a bacterium is dose-dependent. Ultra Violet (UV-visible spectroscopy revealed the size of chemically synthesized gold nanoparticle as 6–40 nm. Atomic force microscopy (AFM analysis confirmed the size and X-ray diffractometry (XRD analysis determined the polycrystalline nature of gold nanoparticles. The present findings explained how gold nanoparticles lyse Gram-negative and Gram-positive bacteria.

International workshop on multimodal analyses enabling artificial agents in human-machine interaction (workshop summary)

NARCIS (Netherlands)

Böck, Ronald; Bonin, Francesca; Campbell, Nick; Poppe, R.W.

2016-01-01

In this paper a brief overview of the third workshop on Multimodal Analyses enabling Artificial Agents in Human-Machine Interaction. The paper is focussing on the main aspects intended to be discussed in the workshop reflecting the main scope of the papers presented during the meeting. The MA3HMI

Sensitization of human carcinoma cells to alkylating agents by small interfering RNA suppression of 3-alkyladenine-DNA glycosylase.

Science.gov (United States)

Paik, Johanna; Duncan, Tod; Lindahl, Tomas; Sedgwick, Barbara

2005-11-15

One of the major cytotoxic lesions generated by alkylating agents is DNA 3-alkyladenine, which can be excised by 3-alkyladenine DNA glycosylase (AAG). Inhibition of AAG may therefore result in increased cellular sensitivity to chemotherapeutic alkylating agents. To investigate this possibility, we have examined the role of AAG in protecting human tumor cells against such agents. Plasmids that express small interfering RNAs targeted to two different regions of AAG mRNA were transfected into HeLa cervical carcinoma cells and A2780-SCA ovarian carcinoma cells. Stable derivatives of both cell types with low AAG protein levels were sensitized to alkylating agents. Two HeLa cell lines with AAG protein levels reduced by at least 80% to 90% displayed a 5- to 10-fold increase in sensitivity to methyl methanesulfonate, N-methyl-N-nitrosourea, and the chemotherapeutic drugs temozolomide and 1,3-bis(2-chloroethyl)-1-nitrosourea. These cells showed no increase in sensitivity to UV light or ionizing radiation. After treatment with methyl methanesulfonate, AAG knockdown HeLa cells were delayed in S phase but accumulated in G2-M. Our data support the hypothesis that ablation of AAG activity in human tumor cells may provide a useful strategy to enhance the efficacy of current chemotherapeutic regimens that include alkylating agents.

TACtic- A Multi Behavioral Agent for Trading Agent Competition

Science.gov (United States)

Khosravi, Hassan; Shiri, Mohammad E.; Khosravi, Hamid; Iranmanesh, Ehsan; Davoodi, Alireza

Software agents are increasingly being used to represent humans in online auctions. Such agents have the advantages of being able to systematically monitor a wide variety of auctions and then make rapid decisions about what bids to place in what auctions. They can do this continuously and repetitively without losing concentration. To provide a means of evaluating and comparing (benchmarking) research methods in this area the trading agent competition (TAC) was established. This paper describes the design, of TACtic. Our agent uses multi behavioral techniques at the heart of its decision making to make bidding decisions in the face of uncertainty, to make predictions about the likely outcomes of auctions, and to alter the agent's bidding strategy in response to the prevailing market conditions.

Taskable Reactive Agent Communities

National Research Council Canada - National Science Library

Myers, Karen

2002-01-01

The focus of Taskable Reactive Agent Communities (TRAC) project was to develop mixed-initiative technology to enable humans to supervise and manage teams of agents as they perform tasks in dynamic environments...

Ehrlichiosis

Science.gov (United States)

... Ehrlichia bacteria can be carried by the: American dog tick Deer tick ( Ixodes scapularis ), which can also ... your vital signs, including: Blood pressure Heart rate Temperature Other tests include: Complete blood count ( CBC ) Granulocyte ...

Disease: H01142 [KEGG MEDICUS

Lifescience Database Archive (English)

Full Text Available H01142 Ehrlichia ewingii infection Human ehrlichiosis is a recently recognized tic...k-borne infection. Ehrlichia ewingii has been identified as a cause of human disease in addition to formerly... known pathogenic Ehrlichia species. Infectious disease ... Ehrlichia ewingii ... 16S rRNA [KO:K01977] ... Other dis... Manian FA, Liddell AM, Schmulewitz N, Storch GA ... TITLE ... Ehrlichia ewingii, a

Modeling culture in intelligent virtual agents

OpenAIRE

Mascarenhas, S.; Degens, N.; Paiva, A.; Prada, R.; Hofstede, G.J.; Beulens, A.J.M.; Aylett, R.

2016-01-01

This work addresses the challenge of creating virtual agents that are able to portray culturally appropriate behavior when interacting with other agents or humans. Because culture influences how people perceive their social reality it is important to have agent models that explicitly consider social elements, such as existing relational factors. We addressed this necessity by integrating culture into a novel model for simulating human social behavior. With this model, we operationalized a par...

Detection of Ehrlichia chaffeensis in adult and nymphal stage lone star ticks (Amblyomma americanum) from Long Island, New York

Science.gov (United States)

Mixson, T.R.; Ginsberg, H.S.; Campbell, S.R.; Sumner, J.W.; Paddock, C.D.

2004-01-01

The lone star tick, Amblyomma americanum (L.), has increased in abundance in several regions of the northeastern United States, including areas of Long Island, NY. Adult and nymphal stage A. americanum collected from several sites on Long Island were evaluated for infection with Ehrlichia chaffeensis, the causative agent of human monocytic ehrlichiosis (HME), by using a nested polymerase chain reaction assay. Fifty-nine (12.5%) of ,17.3 adults and eight of 11.3 pools of five nymphs each (estimated minimum prevalence of infection 1.4%) contained DNA of E. chaffeensis. These data, coupled with the documented expansion of lone star tick populations in the northeastern United States, confirm that E. chaffeensis is endemic to many areas of Long Island and that HME should be considered among the differential diagnoses of the many distinct tick-borne diseases that occur in this region.

Modeling agent's preferences by its designer's social value orientation

Science.gov (United States)

Zuckerman, Inon; Cheng, Kan-Leung; Nau, Dana S.

2018-03-01

Human social preferences have been shown to play an important role in many areas of decision-making. There is evidence from the social science literature that human preferences in interpersonal interactions depend partly on a measurable personality trait called, Social Value Orientation (SVO). Automated agents are often written by humans to serve as their delegates when interacting with other agents. Thus, one might expect an agent's behaviour to be influenced by the SVO of its human designer. With that in mind, we present the following: first, we explore, discuss and provide a solution to the question of how SVO tests that were designed for humans can be used to evaluate agents' social preferences. Second, we show that in our example domain there is a medium-high positive correlation between the social preferences of agents and their human designers. Third, we exemplify how the SVO information of the designer can be used to improve the performance of some other agents playing against those agents, and lastly, we develop and exemplify the behavioural signature SVO model which allows us to better predict performances when interactions are repeated and behaviour is adapted.

Fairness in multi-agent systems

NARCIS (Netherlands)

Jong, de S.; Tuyls, K.P.; Verbeeck, K.

2008-01-01

Multi-agent systems are complex systems in which multiple autonomous entities, called agents, cooperate in order to achieve a common or personal goal. These entities may be computer software, robots, and also humans. In fact, many multi-agent systems are intended to operate in cooperation with or as

Protection against radiation-induced oxidative stress in cultured human epithelial cells by treatment with antioxidant agents

International Nuclear Information System (INIS)

Wan, X. Steven; Ware, Jeffrey H.; Zhou, Zhaozong; Donahue, Jeremiah J.; Guan, Jun; Kennedy, Ann R.

2006-01-01

Purpose: To evaluate the protective effects of antioxidant agents against space radiation-induced oxidative stress in cultured human epithelial cells. Methods and Materials: The effects of selected concentrations of N-acetylcysteine, ascorbic acid, sodium ascorbate, co-enzyme Q10, α-lipoic acid, L-selenomethionine, and vitamin E succinate on radiation-induced oxidative stress were evaluated in MCF10 human breast epithelial cells exposed to radiation with X-rays, γ-rays, protons, or high mass, high atomic number, and high energy particles using a dichlorofluorescein assay. Results: The results demonstrated that these antioxidants are effective in protecting against radiation-induced oxidative stress and complete or nearly complete protection was achieved by treating the cells with a combination of these agents before and during the radiation exposure. Conclusion: The combination of antioxidants evaluated in this study is likely be a promising countermeasure for protection against space radiation-induced adverse biologic effects

Plant-derived human butyrylcholinesterase, but not an organophosphorous-compound hydrolyzing variant thereof, protects rodents against nerve agents

OpenAIRE

Geyer, Brian C.; Kannan, Latha; Garnaud, Pierre-Emmanuel; Broomfield, Clarence A.; Cadieux, C. Linn; Cherni, Irene; Hodgins, Sean M.; Kasten, Shane A.; Kelley, Karli; Kilbourne, Jacquelyn; Oliver, Zeke P.; Otto, Tamara C.; Puffenberger, Ian; Reeves, Tony E.; Robbins, Neil

2010-01-01

The concept of using cholinesterase bioscavengers for prophylaxis against organophosphorous nerve agents and pesticides has progressed from the bench to clinical trial. However, the supply of the native human proteins is either limited (e.g., plasma-derived butyrylcholinesterase and erythrocytic acetylcholinesterase) or nonexisting (synaptic acetylcholinesterase). Here we identify a unique form of recombinant human butyrylcholinesterase that mimics the native enzyme assembly into tetramers; t...

Marketed nonsteroidal anti-inflammatory agents, antihypertensives, and human immunodeficiency virus protease inhibitors: as-yet-unused weapons of the oncologists’ arsenal

Directory of Open Access Journals (Sweden)

Papanagnou P

2015-05-01

Full Text Available Panagiota Papanagnou,1 Panagiotis Baltopoulos,2 Maria Tsironi1 1Department of Nursing, Faculty of Human Movement and Quality of Life Sciences, University of Peloponnese, Sparta, 2Department of Sports Medicine and Biology of Physical Activity, Faculty of Physical Education and Sport Science, National and Kapodistrian University of Athens, Athens, Greece Abstract: Experimental data indicate that several pharmacological agents that have long been used for the management of various diseases unrelated to cancer exhibit profound in vitro and in vivo anticancer activity. This is of major clinical importance, since it would possibly aid in reassessing the therapeutic use of currently used agents for which clinicians already have experience. Further, this would obviate the time-consuming process required for the development and the approval of novel antineoplastic drugs. Herein, both pre-clinical and clinical data concerning the antineoplastic function of distinct commercially available pharmacological agents that are not currently used in the field of oncology, ie, nonsteroidal anti-inflammatory drugs, antihypertensive agents, and anti-human immunodeficiency virus agents inhibiting viral protease, are reviewed. The aim is to provide integrated information regarding not only the molecular basis of the antitumor function of these agents but also the applicability of the reevaluation of their therapeutic range in the clinical setting. Keywords: repositioning, tumorigenesis, pleiotropy, exploitation

Agent-based modeling of endotoxin-induced acute inflammatory response in human blood leukocytes.

Science.gov (United States)

Dong, Xu; Foteinou, Panagiota T; Calvano, Steven E; Lowry, Stephen F; Androulakis, Ioannis P

2010-02-18

Inflammation is a highly complex biological response evoked by many stimuli. A persistent challenge in modeling this dynamic process has been the (nonlinear) nature of the response that precludes the single-variable assumption. Systems-based approaches offer a promising possibility for understanding inflammation in its homeostatic context. In order to study the underlying complexity of the acute inflammatory response, an agent-based framework is developed that models the emerging host response as the outcome of orchestrated interactions associated with intricate signaling cascades and intercellular immune system interactions. An agent-based modeling (ABM) framework is proposed to study the nonlinear dynamics of acute human inflammation. The model is implemented using NetLogo software. Interacting agents involve either inflammation-specific molecules or cells essential for the propagation of the inflammatory reaction across the system. Spatial orientation of molecule interactions involved in signaling cascades coupled with the cellular heterogeneity are further taken into account. The proposed in silico model is evaluated through its ability to successfully reproduce a self-limited inflammatory response as well as a series of scenarios indicative of the nonlinear dynamics of the response. Such scenarios involve either a persistent (non)infectious response or innate immune tolerance and potentiation effects followed by perturbations in intracellular signaling molecules and cascades. The ABM framework developed in this study provides insight on the stochastic interactions of the mediators involved in the propagation of endotoxin signaling at the cellular response level. The simulation results are in accordance with our prior research effort associated with the development of deterministic human inflammation models that include transcriptional dynamics, signaling, and physiological components. The hypothetical scenarios explored in this study would potentially improve

Radiolabelled anti-human fibrin antibody: a new thrombus-detecting agent

International Nuclear Information System (INIS)

Bosnjakovic, V.; Jankovic, B.D.; Horvat, J.; Cvoric, J.

1977-01-01

Rabbit anti-human fibrin globulin (A.F.G.) was labelled with iodine ( 131 I) and used as a thrombus-detecting agent. 131 I-A.F.G. labelled thrombi were displayed by means of a gamma scintillation camera. Normal subjects and patients with thrombo-phlebitis of legs, acute fibrin depositions other than thrombi, and chronic varicosities were examined. The 131 I-A.F.G. technique detected both formed thrombi and those that were forming and could discriminate between acute thrombosis and chronic varicosities. Thrombo-phlebitis and extravascular fibrin depositions were best demonstrated between 24 and 72 hours after 131 I-A.F.G. injection. Radiolabelled A.F.G. in normal veins and chronic varicosities was best displayed within 6 hours of injection. (author)

Comparative genomics of the major agents of human and animal Sporotrichosis: Sporothrix schenckii and Sporothrix brasiliensis

NARCIS (Netherlands)

Teixeira, M.M.; de Almeida, L.G.P.; Kubitschek-Barreira, P.; Alves, F.L.; Kioshima, E.S.; Abadio, A.K.R.; Fernandes, L.; Derengowski, L.S.; Ferreira, K.S.; Souza, R.C.; Ruiz, J.C.; de Andrade, N.C.; Paes, H.C.; Nicola, A.M.; Albuquerque, P.; Gerber, A.L.; Martins, V.P.; Peconick, L.D.F.; Neto, A.V.; Chaucanez, C.B.; Silva, P.A.; cunha, O.L.; de Oliveira, F.F.M.; dos Santos, T.C.; Barros, A.L.N.; Soares, M.A.; de Oliveira, L.M.; Marini, M.M.; Villalobos-Duno, H.; Cunha, M.M.L.; de Hoog, S.; da Silveira, J.F.; Henrissat, B.; Niño-Vega, G.A.; Cisalpino, P.S.; Mora-Montes, H.M.; Almeida, S.R.; Stajich, J.E.; Lopes-Bezerra, L.M.; Vasconcelos, A.T.R.; Felipe, M.S.S.

2014-01-01

Background: The fungal genus Sporothrix includes at least four human pathogenic species. One of these species, S. brasiliensis, is the causal agent of a major ongoing zoonotic outbreak of sporotrichosis in Brazil. Elsewhere, sapronoses are caused by S. schenckii and S. globosa. The major aims on

Culture-specific communication management for virtual agents

DEFF Research Database (Denmark)

Endrass, Birgit; Rehm, Matthias; André, Elisabeth

2009-01-01

Human interaction depends on several individual factors such as personality, social relations, age or gender. But also the society we live in influences our behaviour. Thus culture affects the way communication is led. As virtual agents interact in a more and more human-like manner, culture......, the use of pauses in speech as well as the occurrence of overlapping speech was analyzed and integrated into a demonstrator using virtual agents. In a preliminary study, we investigated whether subjects perceive a difference between agent dialogs that are in line with culture-specific findings and agent...

A real-time architecture for time-aware agents.

Science.gov (United States)

Prouskas, Konstantinos-Vassileios; Pitt, Jeremy V

2004-06-01

This paper describes the specification and implementation of a new three-layer time-aware agent architecture. This architecture is designed for applications and environments where societies of humans and agents play equally active roles, but interact and operate in completely different time frames. The architecture consists of three layers: the April real-time run-time (ART) layer, the time aware layer (TAL), and the application agents layer (AAL). The ART layer forms the underlying real-time agent platform. An original online, real-time, dynamic priority-based scheduling algorithm is described for scheduling the computation time of agent processes, and it is shown that the algorithm's O(n) complexity and scalable performance are sufficient for application in real-time domains. The TAL layer forms an abstraction layer through which human and agent interactions are temporally unified, that is, handled in a common way irrespective of their temporal representation and scale. A novel O(n2) interaction scheduling algorithm is described for predicting and guaranteeing interactions' initiation and completion times. The time-aware predicting component of a workflow management system is also presented as an instance of the AAL layer. The described time-aware architecture addresses two key challenges in enabling agents to be effectively configured and applied in environments where humans and agents play equally active roles. It provides flexibility and adaptability in its real-time mechanisms while placing them under direct agent control, and it temporally unifies human and agent interactions.

Out of the net: An agent-based model to study human movements influence on local-scale malaria transmission.

Directory of Open Access Journals (Sweden)

Francesco Pizzitutti

Full Text Available Though malaria control initiatives have markedly reduced malaria prevalence in recent decades, global eradication is far from actuality. Recent studies show that environmental and social heterogeneities in low-transmission settings have an increased weight in shaping malaria micro-epidemiology. New integrated and more localized control strategies should be developed and tested. Here we present a set of agent-based models designed to study the influence of local scale human movements on local scale malaria transmission in a typical Amazon environment, where malaria is transmission is low and strongly connected with seasonal riverine flooding. The agent-based simulations show that the overall malaria incidence is essentially not influenced by local scale human movements. In contrast, the locations of malaria high risk spatial hotspots heavily depend on human movements because simulated malaria hotspots are mainly centered on farms, were laborers work during the day. The agent-based models are then used to test the effectiveness of two different malaria control strategies both designed to reduce local scale malaria incidence by targeting hotspots. The first control scenario consists in treat against mosquito bites people that, during the simulation, enter at least once inside hotspots revealed considering the actual sites where human individuals were infected. The second scenario involves the treatment of people entering in hotspots calculated assuming that the infection sites of every infected individual is located in the household where the individual lives. Simulations show that both considered scenarios perform better in controlling malaria than a randomized treatment, although targeting household hotspots shows slightly better performance.

Out of the net: An agent-based model to study human movements influence on local-scale malaria transmission.

Science.gov (United States)

Pizzitutti, Francesco; Pan, William; Feingold, Beth; Zaitchik, Ben; Álvarez, Carlos A; Mena, Carlos F

2018-01-01

Though malaria control initiatives have markedly reduced malaria prevalence in recent decades, global eradication is far from actuality. Recent studies show that environmental and social heterogeneities in low-transmission settings have an increased weight in shaping malaria micro-epidemiology. New integrated and more localized control strategies should be developed and tested. Here we present a set of agent-based models designed to study the influence of local scale human movements on local scale malaria transmission in a typical Amazon environment, where malaria is transmission is low and strongly connected with seasonal riverine flooding. The agent-based simulations show that the overall malaria incidence is essentially not influenced by local scale human movements. In contrast, the locations of malaria high risk spatial hotspots heavily depend on human movements because simulated malaria hotspots are mainly centered on farms, were laborers work during the day. The agent-based models are then used to test the effectiveness of two different malaria control strategies both designed to reduce local scale malaria incidence by targeting hotspots. The first control scenario consists in treat against mosquito bites people that, during the simulation, enter at least once inside hotspots revealed considering the actual sites where human individuals were infected. The second scenario involves the treatment of people entering in hotspots calculated assuming that the infection sites of every infected individual is located in the household where the individual lives. Simulations show that both considered scenarios perform better in controlling malaria than a randomized treatment, although targeting household hotspots shows slightly better performance.

Effects of bleaching agents on human enamel light reflectance.

Science.gov (United States)

Markovic, Ljubisa; Fotouhi, Kasra; Lorenz, Heribert; Jordan, Rainer A; Gaengler, Peter; Zimmer, Stefan

2010-01-01

Tooth whitening has been associated with splitting-up chromogenic molecules by hydrogen peroxides. Though micromorphological alterations are well documented, little is known about optical changes as a function of shifting in wavelengths. Therefore, the aim of the current study was to measure reflectance changes after bleaching in vitro by using a spectrometer. Forty-eight enamel slabs (diameter = 5 mm) were prepared from the sound enamel of extracted human teeth that were: 1) fully impacted, 2) from juveniles ages 10 to 16 years, 3) from adults 35 to 45 years of age and 4) from seniors older than age 65. In all specimens, the baseline total reflectance measurement was performed with a computer-assisted spectrometer (Ocean Optics, Dunedin, FL, USA) within wavelengths (wl) from 430 nm to 800 nm. Four enamel samples of each age group were exposed to either 10% or 15% carbamide peroxide (Illuminé Home, Dentsply, Konstanz, Germany) or 35% hydrogen peroxide (Pola Office, SDI Limited, Victoria, Australia). After surface treatment, all slabs underwent total reflectance measurement again. Statistical analysis was calculated at wl 450, 500 and 750 nm using the Student's paired t-test and one-way variance analysis. Total reflectance significantly increased after bleaching at all enamel maturation stages, irrespective of the bleaching agent concentration, for wl 450 nm (blue) and 500 nm (green) with penamel from adults and seniors (pwhitening of the dental enamel works at different maturation stages, even in impacted teeth. This effect is irrespective of the bleaching protocol used and the bleaching agent concentration.

Oxygen-saving effect of a new cardiotonic agent, MCI-154, in diseased human hearts.

Science.gov (United States)

Mori, M; Takeuchi, M; Takaoka, H; Hata, K; Hayashi, Y; Yamakawa, H; Yokoyama, M

1997-03-01

The aim of this study was to examine the left ventricular mechanoenergetic effects of a novel Ca2+ sensitizing agent, MCI-154, on diseased human hearts compared with dobutamine. Unlike conventional cardiotonic agents, a Ca2+ sensitizer that could produce a positive inotropic action by altering the responsiveness of myofilament to Ca2+ could generate force with smaller amounts of Ca2+; thus, it may potentially save energy expenditure. The left ventricular pressure-volume relation and myocardial oxygen consumption per beat (Vo2) were measured by a conductance (volume) catheter and a Webster catheter. Left ventricular contractility (Emax), systolic pressure-volume area (PVA [index of left ventricular total mechanical energy]) and Vo2 were assessed before and after infusion of MCI-154 or dobut-amine. The PVA-independent Vo2 (Vo2 mainly for excitation-contraction coupling) was assessed as the Vo2 at zero PVA. Both agents increased Emax comparably (dobutamine: from 3.55 +/- 1.10 [mean +/- SD] to 5.04 +/- 1.16 mm Hg/ml per m2, p delta PVA-independent Vo2/delta Emax) was less with MCI-154 than with dobutamine (0.14 +/- 0.18 vs. 1.10 +/- 0.80 J/mm Hg per ml per m2, p action mediated by MCI-154 could provide an energetic advantage over the conventional cardiotonic action with currently used inotropic agents.

BrahmVE platform for design and test of Large Scale Multi-agent Human-centric Mission Concepts, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — This Phase I proposal seeks support to extend the BrahmsVE architecture to support a multi-agent human-centric simulation of a hypothetical future ISS which is...

Modeling culture in intelligent virtual agents

NARCIS (Netherlands)

Mascarenhas, S.; Degens, N.; Paiva, A.; Prada, R.; Hofstede, G.J.; Beulens, A.J.M.; Aylett, R.

2016-01-01

This work addresses the challenge of creating virtual agents that are able to portray culturally appropriate behavior when interacting with other agents or humans. Because culture influences how people perceive their social reality it is important to have agent models that explicitly consider social

Research on DNA methylation of human osteosarcoma cell MGMT and its relationship with cell resistance to alkylating agents.

Science.gov (United States)

Guo, Jun; Cui, Qiu; Jiang, WeiHao; Liu, Cheng; Li, DingFeng; Zeng, Yanjun

2013-08-01

The objective of this study was to explore the O(6)-methylguanine-DNA methyltransferase (MGMT) gene methylation status and its protein expression, as well as the effects of demethylating agent 5-Aza-2'-deoxycytidine (5-Aza-CdR) on MGMT gene expression and its resistance to alkylating agents, and to elucidate MGMT expression mechanism and significance in osteosarcoma. The human osteosarcoma cell lines Saos-2 and MG-63 were collected and treated with 5-Aza-CdR for 6 days. The cells not treated with 5-Aza-CdR were set as a negative control. The genomic DNA was extracted from the Saos-2 and MG-63 cells using methylation-specific PCR to detect the promoter CpG island methylation status of the MGMT gene. Cell sensitivity to alkylating agents before and after drug administration was detected by the MTT method. The variation in MGMT gene mRNA and protein was detected by reverse transcription PCR (RT-PCR) and Western blotting. The MGMT promoter gene of normal Saos-2 cells was methylated, with reduced MGMT mRNA and protein expression; the MGMT mRNA and protein expression of Saos-2 cells treated with 5-Aza-CdR was obviously enhanced, and its sensitivity to alkylating agents was reversed. Meanwhile, with promoter CpG island unmethylation of the MGMT gene, MGMT protein was expressed in the normal MG-63 cells and the MG-63 cells treated with 5-Aza-CdR, and both showed resistance to alkylating agents. The methylation status of the MGMT gene promoter in human osteosarcoma cells reflected the cells' ability to induce MGMT protein expression and can be used as a molecular marker to project the sensitivity of cancer tissues to alkylating agent drugs.

Chemical warfare agent simulants for human volunteer trials of emergency decontamination: A systematic review

OpenAIRE

James, Thomas; Wyke, Stacey; Marczylo, Tim; Collins, Samuel; Gaulton, Tom; Foxall, Kerry; Amlôt, Richard; Duarte‐Davidson, Raquel

2017-01-01

Abstract Incidents involving the release of chemical agents can pose significant risks to public health. In such an event, emergency decontamination of affected casualties may need to be undertaken to reduce injury and possible loss of life. To ensure these methods are effective, human volunteer trials (HVTs) of decontamination protocols, using simulant contaminants, have been conducted. Simulants must be used to mimic the physicochemical properties of more harmful chemicals, while remaining ...

HURON (HUman and Robotic Optimization Network) Multi-Agent Temporal Activity Planner/Scheduler

Science.gov (United States)

Hua, Hook; Mrozinski, Joseph J.; Elfes, Alberto; Adumitroaie, Virgil; Shelton, Kacie E.; Smith, Jeffrey H.; Lincoln, William P.; Weisbin, Charles R.

2012-01-01

HURON solves the problem of how to optimize a plan and schedule for assigning multiple agents to a temporal sequence of actions (e.g., science tasks). Developed as a generic planning and scheduling tool, HURON has been used to optimize space mission surface operations. The tool has also been used to analyze lunar architectures for a variety of surface operational scenarios in order to maximize return on investment and productivity. These scenarios include numerous science activities performed by a diverse set of agents: humans, teleoperated rovers, and autonomous rovers. Once given a set of agents, activities, resources, resource constraints, temporal constraints, and de pendencies, HURON computes an optimal schedule that meets a specified goal (e.g., maximum productivity or minimum time), subject to the constraints. HURON performs planning and scheduling optimization as a graph search in state-space with forward progression. Each node in the graph contains a state instance. Starting with the initial node, a graph is automatically constructed with new successive nodes of each new state to explore. The optimization uses a set of pre-conditions and post-conditions to create the children states. The Python language was adopted to not only enable more agile development, but to also allow the domain experts to easily define their optimization models. A graphical user interface was also developed to facilitate real-time search information feedback and interaction by the operator in the search optimization process. The HURON package has many potential uses in the fields of Operations Research and Management Science where this technology applies to many commercial domains requiring optimization to reduce costs. For example, optimizing a fleet of transportation truck routes, aircraft flight scheduling, and other route-planning scenarios involving multiple agent task optimization would all benefit by using HURON.

Anonymity and Software Agents: An Interdiscplinary Challenge

NARCIS (Netherlands)

Brazier, F.M.; Oskamp, A.; Prins, J.M.; Schellekens, M.H.M.; Wijngaards, N.J.E.

2004-01-01

Software agents that play a role in E-commerce and E-government applications involving the Internet often contain information about the identity of their human user such as credit cards and bank accounts. This paper discusses whether this is necessary: whether human users and software agents are

Anonymity and Software Agents: An Interdisciplinary Challenge

NARCIS (Netherlands)

Oskamp, A.; Brazier, F.M.; Prins, J.E.J.; Schellekens, M.H.M.; Wijngaards, N.J.E.

2004-01-01

Software agents that play a role in E-commerce and E-government applications involving the Internet often contain information about the identity of their human user such as credit cards and bank accounts. This paper discusses whether this is necessary: whether human users and software agents are

Conversational Agents, Humorous Act Construction, and Social Intelligence

OpenAIRE

Nijholt, Antinus; Dautenhahn, K.

2005-01-01

Humans use humour to ease communication problems in human-human interaction and in a similar way humour can be used to solve communication problems that arise with human-computer interaction. We discuss the role of embodied conversational agents in human-computer interaction and we have observations on the generation of humorous acts and on the appropriateness of displaying them by embodied conversational agents in order to smoothen, when necessary, their interactions with a human partner. Th...

Goal-based communication using BDI agents as virtual humans in training: An ontology driven dialogue system

NARCIS (Netherlands)

Oijen, J. van; Doesburg, W. van; Dignum, F.

2011-01-01

Simulations for training can greatly benefit from BDI agents as virtual humans playing the role of key players. Learning to communicate effectively is a key aspect of training to command a team that is managing a crisis. In this paper, we present a goal-based dialogue system which has been applied

Methods for Model-Based Reasoning within Agent-Based Ambient Intelligence Applications

NARCIS (Netherlands)

Bosse, T.; Both, F.; Gerritsen, C.; Hoogendoorn, M.; Treur, J.

2012-01-01

Within agent-based Ambient Intelligence applications agents react to humans based on information obtained by sensoring and their knowledge about human functioning. Appropriate types of reactions depend on the extent to which an agent understands the human and is able to interpret the available

Replica of human dentin treated with different desensitizing agents: a methodological SEM study in vitro

Directory of Open Access Journals (Sweden)

Pereira Jose Carlos

2002-01-01

Full Text Available This is a preliminary study to determine a methodological sequence in vitro which may allow the reproduction of dentin for SEM analysis, after the use of different desensitizing agents. Dentin discs obtained from extracted human third molars were etched with 6% citric acid, an artificial smear layer was created and the surface dentin discs were divided into four quadrants. Quadrants 2, 3 and 4 of each disc were conditioned with 6% citric acid. The desensitizing agents (Oxa-Gel®, Gluma Desensitizer and an experimental agent were applied to quadrants 3 and 4. To evaluate the acid resistance of the treatment, quadrant 4 was etched again with 6% citric acid. An impression was then taken with Aquasil ULV. After a setting period of 6 min, each disc was removed from the impression and stored in a moist-free environment for 24 h at 37ºC. After that time, a low-viscosity epoxy resin (Araltec GY 1109 BR was poured into the impression and cured for 24 h. All specimens were metal-coated for SEM analysis. Comparison of the photomicrographs of dentin discs with their respective impressions and resin replicas showed that this technique can reproduce the characteristics of the dentin surface treated with desensitizing agents.

Multi-Agent Modeling in Managing Six Sigma Projects

Directory of Open Access Journals (Sweden)

K. Y. Chau

2009-10-01

Full Text Available In this paper, a multi-agent model is proposed for considering the human resources factor in decision making in relation to the six sigma project. The proposed multi-agent system is expected to increase the acccuracy of project prioritization and to stabilize the human resources service level. A simulation of the proposed multiagent model is conducted. The results show that a multi-agent model which takes into consideration human resources when making decisions about project selection and project team formation is important in enabling efficient and effective project management. The multi-agent modeling approach provides an alternative approach for improving communication and the autonomy of six sigma projects in business organizations.

Evaluation in dogs and humans of three potential technetium-99m myocardial perfusion agents

International Nuclear Information System (INIS)

Gerundini, P.; Savi, A.; Gilardi, M.C.

1986-01-01

The biodistribution of the three cationic /sup 99m/Tc complexes [/sup 99m/Tc(TMP)6]+, [/sup 99m/Tc(POM-POM)3]+, and [/sup 99m/Tc(TBIN)6]+--where TMP represents trimethylphosphite, POM-POM represents 1,2-bis(dimethyoxyphosphino)ethane, and TBIN represents t-butylisonitrile--have been evaluated in humans and dogs. Each agent was studied in three normal volunteers at rest, while [/sup 99m/Tc(POM-POM)3]+ and [/sup 99m/Tc(TBIN)6]+ were each studied in one normal volunteer at exercise. Even though all three agents yield good myocardial images in dogs, none appear suitable for clinical use as myocardial perfusion imaging radiopharmaceuticals. In humans, [/sup 99m/Tc(TMP)6]+ and [/sup 99m/Tc(POM-POM)3]+ clear very slowly from the blood and provide myocardial images only several hours after injection. [/sup 99m/Tc(TBIN)6]+ clears rapidly from the blood, but accumulation in the lung obscures the myocardial image for the first hour after injection; at later times, activity in the liver and spleen masks the apical wall. These results correlate with the blood-binding properties of the three complexes. [/sup 99m/Tc(TMP)6]+ and [/sup 99m/Tc(POM-POM)3]+ bind tightly to the plasma of human blood, but not to the plasma of dog blood; [/sup 99m/Tc(TBIN)6]+ does not bind tightly to the plasma of either dog or human blood. Among the Tc(I) complexes studied to date in humans, [/sup 99m/Tc(TBIN)6]+ appears to be unique in biodistribution pattern, blood-binding properties, and the fact that exercise improves the ultimate myocardial image. All the Tc(I) complexes appear to undergo myocardial accumulation by a mechanism different from that utilized by Tc(III) complexes. Animal studies alone are not adequate to evaluate the potential utility of /sup 99m/Tc cationic complexes for myocardial perfusion studies

Using Cognitive Agents to Train Negotiation Skills

Directory of Open Access Journals (Sweden)

Christopher A. Stevens

2018-02-01

Full Text Available Training negotiation is difficult because it is a complex, dynamic activity that involves multiple parties. It is often not clear how to create situations in which students can practice negotiation or how to measure students' progress. Some have begun to address these issues by creating artificial software agents with which students can train. These agents have the advantage that they can be “reset,” and played against multiple times. This allows students to learn from their mistakes and try different strategies. However, these agents are often based on normative theories of how negotiators should conduct themselves, not necessarily how people actually behave in negotiations. Here, we take a step toward addressing this gap by developing an agent grounded in a cognitive architecture, ACT-R. This agent contains a model of theory-of-mind, the ability of humans to reason about the mental states of others. It uses this model to try to infer the strategy of the opponent and respond accordingly. In a series of experiments, we show that this agent replicates some aspects of human performance, is plausible to human negotiators, and can lead to learning gains in a small-scale negotiation task.

Using Cognitive Agents to Train Negotiation Skills.

Science.gov (United States)

Stevens, Christopher A; Daamen, Jeroen; Gaudrain, Emma; Renkema, Tom; Top, Jakob Dirk; Cnossen, Fokie; Taatgen, Niels A

2018-01-01

Training negotiation is difficult because it is a complex, dynamic activity that involves multiple parties. It is often not clear how to create situations in which students can practice negotiation or how to measure students' progress. Some have begun to address these issues by creating artificial software agents with which students can train. These agents have the advantage that they can be "reset," and played against multiple times. This allows students to learn from their mistakes and try different strategies. However, these agents are often based on normative theories of how negotiators should conduct themselves, not necessarily how people actually behave in negotiations. Here, we take a step toward addressing this gap by developing an agent grounded in a cognitive architecture, ACT-R. This agent contains a model of theory-of-mind, the ability of humans to reason about the mental states of others. It uses this model to try to infer the strategy of the opponent and respond accordingly. In a series of experiments, we show that this agent replicates some aspects of human performance, is plausible to human negotiators, and can lead to learning gains in a small-scale negotiation task.

CHI: A General Agent Communication Framework

Energy Technology Data Exchange (ETDEWEB)

Goldsmith, S.Y.; Phillips, L.R.; Spires, S.V.

1998-12-17

We have completed and exercised a communication framework called CHI (CLOS to HTML Interface) by which agents can communicate with humans. CHI follows HTTP (HyperText Transfer Protocol) and produces HTML (HyperText Markup Language) for use by WWW (World-Wide Web) browsers. CHI enables the rapid and dynamic construction of interface mechanisms. The essence of CHI is automatic registration of dynamically generated interface elements to named objects in the agent's internal environment. The agent can access information in these objects at will. State is preserved, so an agent can pursue branching interaction sequences, activate failure recovery behaviors, and otherwise act opportunistically to maintain a conversation. The CHI mechanism remains transparent in multi-agent, multi-user environments because of automatically generated unique identifiers built into the CHI mechanism. In this paper we discuss design, language, implementation, and extension issues, and, by way of illustration, examine the use of the general CHI/HCHI mechanism in a specific international electronic commerce system. We conclude that the CHI mechanism is an effective, efficient, and extensible means of the agent/human communication.

Humor and Embodied Conversational Agents

NARCIS (Netherlands)

Nijholt, Antinus

This report surveys the role of humor in human-to-human interaction and the possible role of humor in human-computer interaction. The aim is to see whether it is useful for embodied conversational agents to integrate humor capabilities in their internal model of intelligence, emotions and

Pedagogical Agents as Learning Companions: The Impact of Agent Emotion and Gender

Science.gov (United States)

Kim, Yanghee; Baylor, A. L.; Shen, E.

2007-01-01

The potential of emotional interaction between human and computer has recently interested researchers in human-computer interaction. The instructional impact of this interaction in learning environments has not been established, however. This study examined the impact of emotion and gender of a pedagogical agent as a learning companion (PAL) on…

Gold nanoparticles synthesized by Brassica oleracea (Broccoli) acting as antimicrobial agents against human pathogenic bacteria and fungi

Science.gov (United States)

Piruthiviraj, Prakash; Margret, Anita; Krishnamurthy, Poornima Priyadharsani

2016-04-01

Production of antimicrobial agents through the synthesis of gold nanoparticles using green technology has been extensively made consistent by various researchers; yet, this study uses the flower bud's aqueous extracts of Brassica oleracea (Broccoli) as a reducing agent for chloroauric acid (1 mM). After 30 min of incubation, synthesis of gold nanoparticles (AuNps) was observed by a change in extract color from pale yellow to purple color. Synthesis of AuNps was confirmed in UV-visible spectroscopy at the range of approximately 560 nm. The SEM analysis showed the average nanoparticles size of 12-22 nm. The antimicrobial activity of AuNps was analyzed by subjecting it to human pathogenic bacteria (Gram-positive Staphylococcus aureus and Gram-negative Klebsiella pneumonia) and fungi (Aspergillus flavus, Aspergillus niger and Candida albicans) using disc diffusion method. The broccoli-synthesized AuNps showed the efficient antibacterial and antifungal activity of above-mentioned microbes. It was confirmed that AuNps have the best antimicrobial agent compared to the standard antibiotics (Gentamicin and Fluconazole). When the concentrations of AuNps were increased (10, 25, and 50 µg/ml), the sensitivity zone also increased for all the tested microbes. The synthesized AuNps are capable of rendering high antimicrobial efficacy and, hence, have a great potential in the preparation of drugs used against major bacterial and fungal diseases in humans.

How Internet of Things Influences Human Behavior Building Social Web of Services via Agent-Based Approach

Directory of Open Access Journals (Sweden)

Komarov Mikhail

2016-09-01

Full Text Available The paper discovers potential human interactions with growing amount of internet of things (IoT via proposed concept of Social Web of Services (classical social web with smart things - daily life objects connected to the internet. To investigate the impact of IoT on user behaviour patterns we modelled human-thing interactions using agent-based simulation (ABM. We have proved that under certain conditions SmartThings, connected to the IoT, are able to change patterns of Human behaviour. Results of this work predict our way of living in the era of caused by viral effects of IoT application (HCI and M2M connections, and could be used to foster business process management in the IoT era.

A comparative study of different bleaching agents on the morphology of human enamel: an in vitro SEM study.

Science.gov (United States)

Uthappa, Roshan; Suprith, M L; Bhandary, Shreetha; Dash, Sumit

2012-11-01

The purpose of the study was to compare two different commercial bleaching agents, Opalescence with Colgate Platinum, and 30% phosphoric acid used as aggressive agent on the morphology of human enamel. Ten freshly extracted, noncarious, human maxillary central incisors extracted for periodontal reasons were used in this study. The labial surface of the disinfected teeth were polished using a polishing paste with the help of rubber cup and a slow speed handpiece. Each tooth was sectioned at cement-enamel junction and the crown was separated into four specimens, all taken from labial surface. Group 1 was treated with Colgate Platinum for 7 hours, group 2 with Opalescence for 7 hours, group 3 was treated with 30% phosphoric acid for 30 seconds and group 4 was untreated and used as control. After the treatment period, the specimens were washed with normal saline and stored in sterile bottle and sealed. Photomicrographs obtained from the scanning electron microscopy (SEM) after surface treatments were examined for no alteration, slight alteration, moderate alteration and severe alterations. The specimens treated with commercial bleaching agents revealed no enamel surface morphologic alterations compared to control group. The specimen treated with phosphoric acid showed severe alterations. Ten percent carbamide peroxide evaluated in this study does not etch tooth enamel or alter enamel surface morphology as do conventional etching techniques. Carbamine peroxide is a safe and effective tooth whitening agent even when used for extended period of time. The enamel surface remains smooth which reduces caries due to plaque collection.

Proposed Methodology for Application of Human-like gradual Multi-Agent Q-Learning (HuMAQ) for Multi-robot Exploration

International Nuclear Information System (INIS)

Ray, Dip Narayan; Majumder, Somajyoti

2014-01-01

Several attempts have been made by the researchers around the world to develop a number of autonomous exploration techniques for robots. But it has been always an important issue for developing the algorithm for unstructured and unknown environments. Human-like gradual Multi-agent Q-leaming (HuMAQ) is a technique developed for autonomous robotic exploration in unknown (and even unimaginable) environments. It has been successfully implemented in multi-agent single robotic system. HuMAQ uses the concept of Subsumption architecture, a well-known Behaviour-based architecture for prioritizing the agents of the multi-agent system and executes only the most common action out of all the different actions recommended by different agents. Instead of using new state-action table (Q-table) each time, HuMAQ uses the immediate past table for efficient and faster exploration. The proof of learning has also been established both theoretically and practically. HuMAQ has the potential to be used in different and difficult situations as well as applications. The same architecture has been modified to use for multi-robot exploration in an environment. Apart from all other existing agents used in the single robotic system, agents for inter-robot communication and coordination/ co-operation with the other similar robots have been introduced in the present research. Current work uses a series of indigenously developed identical autonomous robotic systems, communicating with each other through ZigBee protocol

FY1995 distributed control of man-machine cooperative multi agent systems; 1995 nendo ningen kyochogata multi agent kikai system no jiritsu seigyo

Energy Technology Data Exchange (ETDEWEB)

NONE

1997-03-01

In the near future, distributed autonomous systems will be practical in many situations, e.g., interactive production systems, hazardous environments, nursing homes, and individual houses. The agents which consist of the distributed system must not give damages to human being and should be working economically. In this project man-machine cooperative multi agent systems are studied in many kind of respects, and basic design technology, basic control technique are developed by establishing fundamental theories and by constructing experimental systems. In this project theoretical and experimental studies are conducted in the following sub-projects: (1) Distributed cooperative control in multi agent type actuation systems (2) Control of non-holonomic systems (3) Man-machine Cooperative systems (4) Robot systems learning human skills (5) Robust force control of constrained systems In each sub-project cooperative nature between machine agent systems and human being, interference between artificial multi agents and environment and new function emergence in coordination of the multi agents and the environment, robust force control against for the environments, control methods for non-holonomic systems, robot systems which can mimic and learn human skills were studied. In each sub-project, some problems were hi-lighted and solutions for the problems have been given based on construction of experimental systems. (NEDO)

Quantifying human behavior uncertainties in a coupled agent-based model for water resources management

Science.gov (United States)

Hyun, J. Y.; Yang, Y. C. E.; Tidwell, V. C.; Macknick, J.

2017-12-01

Modeling human behaviors and decisions in water resources management is a challenging issue due to its complexity and uncertain characteristics that affected by both internal (such as stakeholder's beliefs on any external information) and external factors (such as future policies and weather/climate forecast). Stakeholders' decision regarding how much water they need is usually not entirely rational in the real-world cases, so it is not quite suitable to model their decisions with a centralized (top-down) approach that assume everyone in a watershed follow the same order or pursue the same objective. Agent-based modeling (ABM) uses a decentralized approach (bottom-up) that allow each stakeholder to make his/her own decision based on his/her own objective and the belief of information acquired. In this study, we develop an ABM which incorporates the psychological human decision process by the theory of risk perception. The theory of risk perception quantifies human behaviors and decisions uncertainties using two sequential methodologies: the Bayesian Inference and the Cost-Loss Problem. The developed ABM is coupled with a regulation-based water system model: Riverware (RW) to evaluate different human decision uncertainties in water resources management. The San Juan River Basin in New Mexico (Figure 1) is chosen as a case study area, while we define 19 major irrigation districts as water use agents and their primary decision is to decide the irrigated area on an annual basis. This decision will be affected by three external factors: 1) upstream precipitation forecast (potential amount of water availability), 2) violation of the downstream minimum flow (required to support ecosystems), and 3) enforcement of a shortage sharing plan (a policy that is currently undertaken in the region for drought years). Three beliefs (as internal factors) that correspond to these three external factors will also be considered in the modeling framework. The objective of this study is

DNA excision repair in cell extracts from human cell lines exhibiting hypersensitivity to DNA-damaging agents

International Nuclear Information System (INIS)

Hansson, J.; Keyse, S.M.; Lindahl, T.; Wood, R.D.

1991-01-01

Whole cell extracts from human lymphoid cell lines can perform in vitro DNA repair synthesis in plasmids damaged by agents including UV or cis-diamminedichloroplatinum(II) (cis-DDP). Extracts from xeroderma pigmentosum (XP) cells are defective in repair synthesis. We have now studied in vitro DNA repair synthesis using extracts from lymphoblastoid cell lines representing four human hereditary syndromes with increased sensitivity to DNA-damaging agents. Extracts of cell lines from individuals with the sunlight-sensitive disorders dysplastic nevus syndrome or Cockayne's syndrome (complementation groups A and B) showed normal DNA repair synthesis in plasmids with UV photoproducts. This is consistent with in vivo measurements of the overall DNA repair capacity in such cell lines. A number of extracts were prepared from two cell lines representing the variant form of XP (XP-V). Half of the extracts prepared showed normal levels of in vitro DNA repair synthesis in plasmids containing UV lesions, but the remainder of the extracts from the same cell lines showed deficient repair synthesis, suggesting the possibility of an unusually labile excision repair protein in XP-V. Fanconi's anemia (FA) cells show cellular hypersensitivity to cross-linking agents including cis-DDP. Extracts from cell lines belonging to two different complementation groups of FA showed normal DNA repair synthesis in plasmids containing cis-DDP or UV adducts. Thus, there does not appear to be an overall excision repair defect in FA, but the data do not exclude a defect in the repair of interstrand DNA cross-links

Agent based simulation on the process of human flesh search-From perspective of knowledge and emotion

Science.gov (United States)

Zhu, Hou; Hu, Bin

2017-03-01

Human flesh search as a new net crowed behavior, on the one hand can help us to find some special information, on the other hand may lead to privacy leaking and offending human right. In order to study the mechanism of human flesh search, this paper proposes a simulation model based on agent-based model and complex networks. The computational experiments show some useful results. Discovered information quantity and involved personal ratio are highly correlated, and most of net citizens will take part in the human flesh search or will not take part in the human flesh search. Knowledge quantity does not influence involved personal ratio, but influences whether HFS can find out the target human. When the knowledge concentrates on hub nodes, the discovered information quantity is either perfect or almost zero. Emotion of net citizens influences both discovered information quantity and involved personal ratio. Concretely, when net citizens are calm to face the search topic, it will be hardly to find out the target; But when net citizens are agitated, the target will be found out easily.

Alkylating chemotherapeutic agents cyclophosphamide and melphalan cause functional injury to human bone marrow-derived mesenchymal stem cells.

Science.gov (United States)

Kemp, Kevin; Morse, Ruth; Sanders, Kelly; Hows, Jill; Donaldson, Craig

2011-07-01

The adverse effects of melphalan and cyclophosphamide on hematopoietic stem cells are well-known; however, the effects on the mesenchymal stem cells (MSCs) residing in the bone marrow are less well characterised. Examining the effects of chemotherapeutic agents on patient MSCs in vivo is difficult due to variability in patients and differences in the drug combinations used, both of which could have implications on MSC function. As drugs are not commonly used as single agents during high-dose chemotherapy (HDC) regimens, there is a lack of data comparing the short- or long-term effects these drugs have on patients post treatment. To help address these problems, the effects of the alkylating chemotherapeutic agents cyclophosphamide and melphalan on human bone marrow MSCs were evaluated in vitro. Within this study, the exposure of MSCs to the chemotherapeutic agents cyclophosphamide or melphalan had strong negative effects on MSC expansion and CD44 expression. In addition, changes were seen in the ability of MSCs to support hematopoietic cell migration and repopulation. These observations therefore highlight potential disadvantages in the use of autologous MSCs in chemotherapeutically pre-treated patients for future therapeutic strategies. Furthermore, this study suggests that if the damage caused by chemotherapeutic agents to marrow MSCs is substantial, it would be logical to use cultured allogeneic MSCs therapeutically to assist or repair the marrow microenvironment after HDC.

Development of 68Ga-labeled mannosylated human serum albumin (MSA) as a lymph node imaging agent for positron emission tomography

International Nuclear Information System (INIS)

Choi, Jae Yeon; Jeong, Jae Min; Yoo, Byong Chul; Kim, Kyunggon; Kim, Youngsoo; Yang, Bo Yeun; Lee, Yun-Sang; Lee, Dong Soo; Chung, June-Key; Lee, Myung Chul

2011-01-01

Introduction: Although many sentinel lymph node (SLN) imaging agents labeled with 99m Tc have been developed, no positron-emitting agent has been specifically designed for SLN imaging. Furthermore, the development of the beta probe and the requirement for better image resolution have increased the need for a positron-emitting SLN imaging agent. Here, we describe the development of a novel positron-emitting SLN imaging agent labeled with 68 Ga. Methods: A mannosylated human serum albumin (MSA) was synthesized by conjugating α-D-mannopyranosylphenyl isothiocyanate to human serum albumin in sodium carbonate buffer (pH 9.5), and then 2-(p-isothiocyanatobenzyl)-1,4,7-triazacyclononane-1,4,7-triacetic acid was conjugated to synthesize NOTA-MSA. Numbers of mannose and NOTA units conjugated in NOTA-MSA were determined by matrix-assisted laser desorption ionization time-of-flight mass spectrometry. NOTA-MSA was labeled with 68 Ga at room temperature. The stability of 68 Ga-NOTA-MSA was checked in labeling medium at room temperature and in human serum at 37 o C. Biodistribution in normal ICR mice was investigated after tail vein injection, and micro-positron emission tomography (PET) images were obtained after injecting 68 Ga-NOTA-MSA into a tail vein or a footpad. Results: The numbers of conjugated α-D-mannopyranosylphenyl isothiocyanate and 2-(p-isothiocyanatobenzyl)-1,4,7-triazacyclononane-1,4,7-triacetic acid units in NOTA-MSA were 10.6 and 6.6, respectively. The labeling efficiency of 68 Ga-NOTA-MSA was greater than 99% at room temperature, and its stability was greater than 99% at 4 h. Biodistribution and micro-PET studies of 68 Ga-NOTA-MSA showed high liver and spleen uptakes after intravenous injection. 68 Ga-NOTA-MSA injected into a footpad rapidly migrated to the lymph node. Conclusions: 68 Ga-NOTA-MSA was successfully developed as a novel SLN imaging agent for PET. NOTA-MSA is easily labeled at high efficiency, and subcutaneously administered 68 Ga-NOTA-MSA was

Do you get it? User-evaluated explainable BDI agents

NARCIS (Netherlands)

Broekens, J.; Harbers, M.; Hindriks, K.; Bosch, K. van den; Jonker, C.; Meyer, J.J.C.

2010-01-01

In this paper we focus on explaining to humans the behavior of autonomous agents, i.e., explainable agents. Explainable agents are useful for many reasons including scenario-based training (e.g. disaster training), tutor and pedagogical systems, agent development and debugging, gaming, and

An embodiment effect in computer-based learning with animated pedagogical agents.

Science.gov (United States)

Mayer, Richard E; DaPra, C Scott

2012-09-01

How do social cues such as gesturing, facial expression, eye gaze, and human-like movement affect multimedia learning with onscreen agents? To help address this question, students were asked to twice view a 4-min narrated presentation on how solar cells work in which the screen showed an animated pedagogical agent standing to the left of 11 successive slides. Across three experiments, learners performed better on a transfer test when a human-voiced agent displayed human-like gestures, facial expression, eye gaze, and body movement than when the agent did not, yielding an embodiment effect. In Experiment 2 the embodiment effect was found when the agent spoke in a human voice but not in a machine voice. In Experiment 3, the embodiment effect was found both when students were told the onscreen agent was consistent with their choice of agent characteristics and when inconsistent. Students who viewed a highly embodied agent also rated the social attributes of the agent more positively than did students who viewed a nongesturing agent. The results are explained by social agency theory, in which social cues in a multimedia message prime a feeling of social partnership in the learner, which leads to deeper cognitive processing during learning, and results in a more meaningful learning outcome as reflected in transfer test performance.

A multi-agent system for coordinating international shipping

Energy Technology Data Exchange (ETDEWEB)

Goldsmith, S.Y.; Phillips, L.R.; Spires, S.V.

1998-05-01

Moving commercial cargo across the US-Mexico border is currently a complex, paper-based, error-prone process that incurs expensive inspections and delays at several ports of entry in the Southwestern US. Improved information handling will dramatically reduce border dwell time, variation in delivery time, and inventories, and will give better control of the shipment process. The Border Trade Facilitation System (BTFS) is an agent-based collaborative work environment that assists geographically distributed commercial and government users with transshipment of goods across the US-Mexico border. Software agents mediate the creation, validation and secure sharing of shipment information and regulatory documentation over the Internet, using the World Wide Web to interface with human actors. Agents are organized into Agencies. Each agency represents a commercial or government agency. Agents perform four specific functions on behalf of their user organizations: (1) agents with domain knowledge elicit commercial and regulatory information from human specialists through forms presented via web browsers; (2) agents mediate information from forms with diverse otologies, copying invariant data from one form to another thereby eliminating the need for duplicate data entry; (3) cohorts of distributed agents coordinate the work flow among the various information providers and they monitor overall progress of the documentation and the location of the shipment to ensure that all regulatory requirements are met prior to arrival at the border; (4) agents provide status information to human actors and attempt to influence them when problems are predicted.

Design of a multi-agent hydroeconomic model to simulate a complex human-water system: Early insights from the Jordan Water Project

Science.gov (United States)

Yoon, J.; Klassert, C. J. A.; Lachaut, T.; Selby, P. D.; Knox, S.; Gorelick, S.; Rajsekhar, D.; Tilmant, A.; Avisse, N.; Harou, J. J.; Gawel, E.; Klauer, B.; Mustafa, D.; Talozi, S.; Sigel, K.

2015-12-01

Our work focuses on development of a multi-agent, hydroeconomic model for purposes of water policy evaluation in Jordan. The model adopts a modular approach, integrating biophysical modules that simulate natural and engineered phenomena with human modules that represent behavior at multiple levels of decision making. The hydrologic modules are developed using spatially-distributed groundwater and surface water models, which are translated into compact simulators for efficient integration into the multi-agent model. For the groundwater model, we adopt a response matrix method approach in which a 3-dimensional MODFLOW model of a complex regional groundwater system is converted into a linear simulator of groundwater response by pre-processing drawdown results from several hundred numerical simulation runs. Surface water models for each major surface water basin in the country are developed in SWAT and similarly translated into simple rainfall-runoff functions for integration with the multi-agent model. The approach balances physically-based, spatially-explicit representation of hydrologic systems with the efficiency required for integration into a complex multi-agent model that is computationally amenable to robust scenario analysis. For the multi-agent model, we explicitly represent human agency at multiple levels of decision making, with agents representing riparian, management, supplier, and water user groups. The agents' decision making models incorporate both rule-based heuristics as well as economic optimization. The model is programmed in Python using Pynsim, a generalizable, open-source object-oriented code framework for modeling network-based water resource systems. The Jordan model is one of the first applications of Pynsim to a real-world water management case study. Preliminary results from a tanker market scenario run through year 2050 are presented in which several salient features of the water system are investigated: competition between urban and

Fronto-parietal coding of goal-directed actions performed by artificial agents.

Science.gov (United States)

Kupferberg, Aleksandra; Iacoboni, Marco; Flanagin, Virginia; Huber, Markus; Kasparbauer, Anna; Baumgartner, Thomas; Hasler, Gregor; Schmidt, Florian; Borst, Christoph; Glasauer, Stefan

2018-03-01

With advances in technology, artificial agents such as humanoid robots will soon become a part of our daily lives. For safe and intuitive collaboration, it is important to understand the goals behind their motor actions. In humans, this process is mediated by changes in activity in fronto-parietal brain areas. The extent to which these areas are activated when observing artificial agents indicates the naturalness and easiness of interaction. Previous studies indicated that fronto-parietal activity does not depend on whether the agent is human or artificial. However, it is unknown whether this activity is modulated by observing grasping (self-related action) and pointing actions (other-related action) performed by an artificial agent depending on the action goal. Therefore, we designed an experiment in which subjects observed human and artificial agents perform pointing and grasping actions aimed at two different object categories suggesting different goals. We found a signal increase in the bilateral inferior parietal lobule and the premotor cortex when tool versus food items were pointed to or grasped by both agents, probably reflecting the association of hand actions with the functional use of tools. Our results show that goal attribution engages the fronto-parietal network not only for observing a human but also a robotic agent for both self-related and social actions. The debriefing after the experiment has shown that actions of human-like artificial agents can be perceived as being goal-directed. Therefore, humans will be able to interact with service robots intuitively in various domains such as education, healthcare, public service, and entertainment. © 2017 Wiley Periodicals, Inc.

Aspects of agents for safeguards

International Nuclear Information System (INIS)

Kotte, U.

1999-01-01

With the development of the Internet and the WWW, information treatment has gained a new dimension. (Intelligent) software agents are one of the means expected to relieve human staff of the burden of information overload, and in the future to contribute to safeguards data acquisition, data evaluation and decision-making. An overview is given for the categories of Internet, intranet and desktop agents. Aspects of the potential application of agents are described in three fields: information access and delivery, collaboration and workflow management, adaptive interfaces and learning assistants. Routine application of agents is not yet in sight, but the scientific and technical progress seems to be encouraging. (author)

The role of genetic background in susceptibility to chemical warfare nerve agents across rodent and non-human primate models.

Science.gov (United States)

Matson, Liana M; McCarren, Hilary S; Cadieux, C Linn; Cerasoli, Douglas M; McDonough, John H

2018-01-15

Genetics likely play a role in various responses to nerve agent exposure, as genetic background plays an important role in behavioral, neurological, and physiological responses to environmental stimuli. Mouse strains or selected lines can be used to identify susceptibility based on background genetic features to nerve agent exposure. Additional genetic techniques can then be used to identify mechanisms underlying resistance and sensitivity, with the ultimate goal of developing more effective and targeted therapies. Here, we discuss the available literature on strain and selected line differences in cholinesterase activity levels and response to nerve agent-induced toxicity and seizures. We also discuss the available cholinesterase and toxicity literature across different non-human primate species. The available data suggest that robust genetic differences exist in cholinesterase activity, nerve agent-induced toxicity, and chemical-induced seizures. Available cholinesterase data suggest that acetylcholinesterase activity differs across strains, but are limited by the paucity of carboxylesterase data in strains and selected lines. Toxicity and seizures, two outcomes of nerve agent exposure, have not been fully evaluated for genetic differences, and thus further studies are required to understand baseline strain and selected line differences. Published by Elsevier B.V.

Spectra from 2.5-15 μm of tissue phantom materials, optical clearing agents and ex vivo human skin: implications for depth profiling of human skin

International Nuclear Information System (INIS)

Viator, John A; Choi, Bernard; Peavy, George M; Kimel, Sol; Nelson, J Stuart

2003-01-01

Infrared measurements have been used to profile or image biological tissue, including human skin. Usually, analysis of such measurements has assumed that infrared absorption is due to water and collagen. Such an assumption may be reasonable for soft tissue, but introduction of exogenous agents into skin or the measurement of tissue phantoms has raised the question of their infrared absorption spectrum. We used Fourier transform infrared spectroscopy in attenuated total reflection mode to measure the infrared absorption spectra, in the range of 2-15 μm, of water, polyacrylamide, Intralipid, collagen gels, four hyperosmotic clearing agents (glycerol, 1,3-butylene glycol, trimethylolpropane, Topicare TM ), and ex vivo human stratum corneum and dermis. The absorption spectra of the phantom materials were similar to that of water, although additional structure was noted in the range of 6-10 μm. The absorption spectra of the clearing agents were more complex, with molecular absorption bands dominating between 6 and 12 μm. Dermis was similar to water, with collagen structure evident in the 6-10 μm range. Stratum corneum had a significantly lower absorption than dermis due to a lower content of water. These results suggest that the assumption of water-dominated absorption in the 2.5-6 μm range is valid. At longer wavelengths, clearing agent absorption spectra differ significantly from the water spectrum. This spectral information can be used in pulsed photothermal radiometry or utilized in the interpretation of reconstructions in which a constant μ ir is used. In such cases, overestimating μ ir will underestimate chromophore depth and vice versa, although the effect is dependent on actual chromophore depth. (note)

Investigating the influence of social exclusion on persuasion by a virtual agent

NARCIS (Netherlands)

Ruijten, P.A.M.; Ham, J.R.C.; Midden, C.J.H.; Spagnolli, A.; Chittaro, L.; Gamberini, L.

2014-01-01

Persuasive agents may function as a tool to induce changes in human behavior. Research has shown that human-likeness of such agents influences their effectiveness. Besides characteristics of the agent, other characteristics may also have strong influences on persuasive agents’ effectiveness. One

Epidemiology and quantitation of environmental risk in humans from radiation and other agents

International Nuclear Information System (INIS)

Castellani, Amleto

1985-01-01

The identification and quantitation of environmental risk in humans is one of the main problems to be solved in order to improve the protection of individuals and of human populations against physical and chemical pollutants. Epidemiology plays a central role in the evaluation of health risk directly in human populations. In this volume are collected 33 lectures presented at the AS! course on ''Epidemiology and quantitation of environmental risk in humans from radiation and other agents: potential and limitations'', sponsored by NATO and Italian Association of Radiobiology and organized by ENEA. The course has been devoted to a number of aspects of environmental risk analysis and evaluation based on epidemiological investigation. Basic epidemiological concepts and methods have been reviewed. Fundamentals of dosimetry and microdosimetry were presented in relation to the contribution of epidemiology in defining the dose effect relationships for radiation carcinogenesis and its relation with age, sex and ethnicity. The mechanisms of carcinogenesis as a multi-stage process were illustrated. One of the main topics was 'cancer epidemiology' and its correlation with: - occupational and non-occupational exposure to radiation - diagnostic and therapeutic irradiation - cancer proneness - hereditary and familiar diseases - abnormal response to carcinogens - environmental pollution in air and water - exposure to radon in mines and in building material - atomic bomb explosion - chemotherapy - dioxin and related compounds

CATS-based Air Traffic Controller Agents

Science.gov (United States)

Callantine, Todd J.

2002-01-01

This report describes intelligent agents that function as air traffic controllers. Each agent controls traffic in a single sector in real time; agents controlling traffic in adjoining sectors can coordinate to manage an arrival flow across a given meter fix. The purpose of this research is threefold. First, it seeks to study the design of agents for controlling complex systems. In particular, it investigates agent planning and reactive control functionality in a dynamic environment in which a variety perceptual and decision making skills play a central role. It examines how heuristic rules can be applied to model planning and decision making skills, rather than attempting to apply optimization methods. Thus, the research attempts to develop intelligent agents that provide an approximation of human air traffic controller behavior that, while not based on an explicit cognitive model, does produce task performance consistent with the way human air traffic controllers operate. Second, this research sought to extend previous research on using the Crew Activity Tracking System (CATS) as the basis for intelligent agents. The agents use a high-level model of air traffic controller activities to structure the control task. To execute an activity in the CATS model, according to the current task context, the agents reference a 'skill library' and 'control rules' that in turn execute the pattern recognition, planning, and decision-making required to perform the activity. Applying the skills enables the agents to modify their representation of the current control situation (i.e., the 'flick' or 'picture'). The updated representation supports the next activity in a cycle of action that, taken as a whole, simulates air traffic controller behavior. A third, practical motivation for this research is to use intelligent agents to support evaluation of new air traffic control (ATC) methods to support new Air Traffic Management (ATM) concepts. Current approaches that use large, human

The enhanced inhibitory effect of different antitumor agents in self-microemulsifying drug delivery systems on human cervical cancer HeLa cells.

Science.gov (United States)

Ujhelyi, Zoltán; Kalantari, Azin; Vecsernyés, Miklós; Róka, Eszter; Fenyvesi, Ferenc; Póka, Róbert; Kozma, Bence; Bácskay, Ildikó

2015-07-21

The aim of this study was to develop topical self-microemulsifying drug delivery systems (SMEDDS) containing antitumor agents (bleomycin, cisplatin and ifosfamide) and to investigate their inhibitory potential in SMEDDS on human cervical cancer HeLa cells. The physicochemical properties of cytostatic drug loaded SMEDDS were characterized. The cytotoxicity of main components of SMEDDS was also investigated. Their IC50 values were determined. HeLa cells were treated by different concentrations of cisplatin, bleomycin and ifosfamide alone and in various SMEDDS. The inhibitory effect on cell growth was analyzed by MTT cell viability assay. Inflammation is a driving force that accelerates cancer development. The inhibitory effect of these antitumor agents has also been tested on HeLa cells in the presence of inflammatory mediators (IL-1-β, TNF-α) as an in vitro model of inflamed human cervix. Significant differences in the cytotoxicity of cytostatic drugs alone and in SMEDDS have been found in a concentration-dependent manner. The self-micro emulsifying system may potentiate the effectiveness of bleomycin, cisplatin and ifosfamide topically. The effect of SMEDDS containing antitumor agents was decreased significantly in the presence of inflammatory mediators. According to our experiments, the optimal SMEDDS formulation is 1:1:2:6:2 ratios of Isopropyl myristate, Capryol 90, Kolliphor RH 40, Cremophor RH40, Transcutol HP and Labrasol. It can be concluded that SMEDDS may increase the inhibitory effect of bleomycin, ifosfamide and cisplatin on human cervical cancer HeLa cells. Inflammation on HeLa cells hinders the effectiveness of SMEDDS containing antitumor agents. Our results might ensure useful data for development of optimal antitumor formulations.

Nitrites and nitrates in the human diet: Carcinogens or beneficial hypotensive agents?

Science.gov (United States)

Butler, Anthony

2015-06-05

The presence of nitrite in the human diet was thought to constitute a hazard as secondary nitrosamines are known to cause gastric cancers. Recent publications on the physiology of serum nitrite have been consulted. Nitrite is added to some foodstuffs as an antibotulinum agent. The epidemiological evidence that nitrite causes gastric ulcers is weak. On the other hand, evidence that the presence of nitrite in serum lowers blood pressure is strong. This allows us to explain why a Tang dynasty treatment for angina, given in a Dunhuang medical manuscript, can be successful. The presence of nitrite in food is free of danger and a diet high in nitrate is beneficial to the health. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Different impressions of other agents obtained through social interaction uniquely modulate dorsal and ventral pathway activities in the social human brain.

Science.gov (United States)

Takahashi, Hideyuki; Terada, Kazunori; Morita, Tomoyo; Suzuki, Shinsuke; Haji, Tomoki; Kozima, Hideki; Yoshikawa, Masahiro; Matsumoto, Yoshio; Omori, Takashi; Asada, Minoru; Naito, Eiichi

2014-09-01

Internal (neuronal) representations in the brain are modified by our experiences, and this phenomenon is not unique to sensory and motor systems. Here, we show that different impressions obtained through social interaction with a variety of agents uniquely modulate activity of dorsal and ventral pathways of the brain network that mediates human social behavior. We scanned brain activity with functional magnetic resonance imaging (fMRI) in 16 healthy volunteers when they performed a simple matching-pennies game with a human, human-like android, mechanical robot, interactive robot, and a computer. Before playing this game in the scanner, participants experienced social interactions with each opponent separately and scored their initial impressions using two questionnaires. We found that the participants perceived opponents in two mental dimensions: one represented "mind-holderness" in which participants attributed anthropomorphic impressions to some of the opponents that had mental functions, while the other dimension represented "mind-readerness" in which participants characterized opponents as intelligent. Interestingly, this "mind-readerness" dimension correlated to participants frequently changing their game tactic to prevent opponents from envisioning their strategy, and this was corroborated by increased entropy during the game. We also found that the two factors separately modulated activity in distinct social brain regions. Specifically, mind-holderness modulated activity in the dorsal aspect of the temporoparietal junction (TPJ) and medial prefrontal and posterior paracingulate cortices, while mind-readerness modulated activity in the ventral aspect of TPJ and the temporal pole. These results clearly demonstrate that activity in social brain networks is modulated through pre-scanning experiences of social interaction with a variety of agents. Furthermore, our findings elucidated the existence of two distinct functional networks in the social human brain

The Herb Medicine Formula “Chong Lou Fu Fang” Increases the Cytotoxicity of Chemotherapeutic Agents and Down-Regulates the Expression of Chemotherapeutic Agent Resistance-Related Genes in Human Gastric Cancer Cells In Vitro

Directory of Open Access Journals (Sweden)

Yongping Liu

2011-01-01

Full Text Available The herb medicine formula “Chong Lou Fu Fang” (CLFF has efficacy in inhibiting the proliferation of human gastric cancer in vitro and in vivo. To explore the potentially useful combination of CLFF with chemotherapeutic agents commonly used in gastric cancer therapy, we assess the interaction between CLFF and these chemotherapeutic agents in both SGC-7901 cell lines and BGC-823 cell lines using a median effect analysis and apoptosis analysis, and we also investigate the influence of CLFF on chemotherapeutic agent-associated gene expression. The synergistic analysis indicated that CLFF had a synergistic effect on the cytotoxicity of 5-fluorouracil (5-FU in a relative broad dose inhibition range (20–95% fraction affected in SGC-7901cell lines and 5–65% fraction affected in BGC-823 cell lines, while the synergistic interaction between CLFF and oxaliplatin or docetaxel only existed in a low dose inhibition range (≤50% fraction affected in both cell lines. Combination of CLFF and chemotherapeutic agents could also induce apoptosis in a synergistic manner. After 24 h, CLFF alone or CLFF combination with chemotherapeutic agents could significantly suppress the levels of expression of chemotherapeutic agent resistance related genes in gastric cancer cells. Our findings indicate that there are useful synergistic interactions between CLFF and chemotherapeutic agents in gastric cancer cells, and the possible mechanisms might be partially due to the down-regulation of chemotherapeutic agent resistance related genes and the synergistic apoptotic effect.

Complement-induced histamine release from human basophils. III. Effect of pharmacologic agents.

Science.gov (United States)

Hook, W A; Siraganian, R P

1977-02-01

Human serum activated with zymosan generates a factor (C5a) that releases histamine from autologous basophils. Previously we have presented evidence that this mechanism for C5a-induced release differs from IgE-mediated reactions. The effect of several pharmacologic agents known to alter IgE-mediated release was studied to determine whether they have a similar action on serum-induced release. Deuterium oxide (D2O), which enhances allergic release, inhibited in a concentration-dependent fashion the serum-induced reaction at incubation temperatures of 25 and 32 degrees C. The colchicine-induced inhibition was not reversed by D2O. Cytochalasin B, which gives a variable enhancement of IgE-mediated release, had a marked enhancing effect on the serum-induced reaction in all subjects tested. The following agents known to inhibit the IgE-mediated reaction also inhibited serum-induced release at 25 degrees C: colchicine, dibutyryl cyclic AMP, aminophylline, isoproterenol, cholera toxin, chlorphenesin, diethylcarbamazine, and 2-deoxy-D-glucose. These results suggest that the serum-induced release is modulated by intracellular cyclic AMP, requires energy, and is enhanced by the disruption of microfilaments. The lack of an effect by D2O would suggest that microtubular stabilization is not required. The data can be interpreted to indicate that IgE- and C5a-mediated reactions diverge at a late stage in the histamine release pathway.

Cavitation thresholds of contrast agents in an in vitro human clot model exposed to 120-kHz ultrasound.

Science.gov (United States)

Gruber, Matthew J; Bader, Kenneth B; Holland, Christy K

2014-02-01

Ultrasound contrast agents (UCAs) can be employed to nucleate cavitation to achieve desired bioeffects, such as thrombolysis, in therapeutic ultrasound applications. Effective methods of enhancing thrombolysis with ultrasound have been examined at low frequencies (cavitation thresholds for two UCAs exposed to 120-kHz ultrasound. A commercial ultrasound contrast agent (Definity(®)) and echogenic liposomes were investigated to determine the acoustic pressure threshold for ultraharmonic (UH) and broadband (BB) generation using an in vitro flow model perfused with human plasma. Cavitation emissions were detected using two passive receivers over a narrow frequency bandwidth (540-900 kHz) and a broad frequency bandwidth (0.54-1.74 MHz). UH and BB cavitation thresholds occurred at the same acoustic pressure (0.3 ± 0.1 MPa, peak to peak) and were found to depend on the sensitivity of the cavitation detector but not on the nucleating contrast agent or ultrasound duty cycle.

Moral actor, selfish agent.

Science.gov (United States)

Frimer, Jeremy A; Schaefer, Nicola K; Oakes, Harrison

2014-05-01

People are motivated to behave selfishly while appearing moral. This tension gives rise to 2 divergently motivated selves. The actor-the watched self-tends to be moral; the agent-the self as executor-tends to be selfish. Three studies present direct evidence of the actor's and agent's distinct motives. To recruit the self-as-actor, we asked people to rate the importance of various goals. To recruit the self-as-agent, we asked people to describe their goals verbally. In Study 1, actors claimed their goals were equally about helping the self and others (viz., moral); agents claimed their goals were primarily about helping the self (viz., selfish). This disparity was evident in both individualist and collectivist cultures, attesting to the universality of the selfish agent. Study 2 compared actors' and agents' motives to those of people role-playing highly prosocial or selfish exemplars. In content (Study 2a) and in the impressions they made on an outside observer (Study 2b), actors' motives were similar to those of the prosocial role-players, whereas agents' motives were similar to those of the selfish role-players. Study 3 accounted for the difference between the actor and agent: Participants claimed that their agent's motives were the more realistic and that their actor's motives were the more idealistic. The selfish agent/moral actor duality may account for why implicit and explicit measures of the same construct diverge, and why feeling watched brings out the better angels of human nature.

CEST and PARACEST MR contrast agents

International Nuclear Information System (INIS)

Hancu, Ileana; Dixon, W. Thomas; Woods, Mark; Sherry, A. Dean; Vinogradov, Elena; Lenkinski, Robert E.

2010-01-01

In this review we describe the status of development for a new class of magnetic resonance (MR) contrast agents, based on chemical exchange saturation transfer (CEST). The mathematics and physics relevant to the description of the CEST effect in MR are presented in an appendix published in the online version only. We discuss the issues arising when translating in vitro results obtained with CEST agents to using these MR agents in in vivo model studies and in humans. Examples are given on how these agents are imaged in vivo. We summarize the status of development of these CEST agents, and speculate about the next steps that may be taken towards the demonstration of CEST MR imaging in clinical applications

Modulation of phenotype and function of human CD4+CD25+ T regulatory lymphocytes mediated by cAMP elevating agents

Directory of Open Access Journals (Sweden)

Antonella Riccomi

2016-09-01

Full Text Available We have shown that Cholera Toxin (CT and other cyclic AMP (cAMP elevating agents induce up-regulation of the inhibitory molecule CTLA-4 in human resting CD4+ T lymphocytes, which following the treatment acquired suppressive functions. In this study, we evaluated the effect of cAMP elevating agents on human CD4+CD25+ T cells, which include the T regulatory (Treg cells that play a pivotal role in the maintenance of immunological tolerance. We found that cAMP elevating agents induce up-regulation of CTLA-4 in CD4+CD25- and further enhance its expression in CD4+CD25+ T cells. We observed an increase of two isoforms of mRNA coding for the membrane and the soluble CTLA-4 molecules, suggesting that the regulation of CTLA-4 expression by cAMP is at the transcriptional level. In addition, we found that the increase of cAMP in CD4+CD25+ T cells converts the CD4+CD25+Foxp3- T cells in CD4+CD25+Foxp3+ T cells, whereas the increase of cAMP in CD4+CD25- T cells did not up-regulate Foxp3 in the absence of activation stimuli. To investigate the function of these cells, we performed an in vitro suppression assay by culturing CD4+CD25+ T cells untreated or pre-treated with CT with anti-CD3 mAbs-stimulated autologous PBMC. We found that CT enhances the inhibitory function of CD4+CD25+ T cells, CD4+ and CD8+ T cell proliferation and IFNγ production are strongly inhibited by CD4+CD25+ T cells pre-treated with cAMP elevating agents. Furthermore, we found that CD4+CD25+ T lymphocytes pre-treated with cAMP elevating agents induce the up-regulation of CD80 and CD86 co-stimulatory molecules on immature dendritic cells (DCs in the absence of antigenic stimulation, however without leading to full DC maturation. These data show that the increase of intracellular cAMP modulates the phenotype and function of human CD4+CD25+ T cells.

In Vitro Efficacy and Mechanistic Role of Indocyanine Green as a Photodynamic Therapy Agent for Human Melanoma

Energy Technology Data Exchange (ETDEWEB)

Mamoon, A.; Gamal-Eldeen, A; Ruppel, M; Smith, R; Tsang, T; Miller, L

2009-01-01

Photodynamic therapy (PDT) is a promising treatment for superficial cancer. However, poor therapeutic results have been reported for melanoma, due to the high melanin content. Indocyanine green (ICG) has near infrared absorption (700-800nm) and melanins do not absorb strongly in this area. This study explores the efficiency of ICG as a PDT agent for human melanoma, and its mechanistic role in the cell death pathway.

Research Recommendations for Selected IARC-Classified Agents

DEFF Research Database (Denmark)

Ward, Elizabeth M; Schulte, Paul A; Straif, Kurt

2010-01-01

OBJECTIVES: There are some common occupational agents and exposure circumstances where evidence of carcinogenicity is substantial but not yet conclusive for humans. The objectives are to identify research gaps and needs for twenty agents prioritized for review based on evidence of widespread huma...

DNA repair in human cells exposed to combinations of carcinogenic agents

International Nuclear Information System (INIS)

Setlow, R.B.; Ahmed, F.E.

1980-01-01

Normal human and XP 2 fibroblasts were treated with uv plus uv-mimetic chemicals. The uv dose used was sufficient to saturate the uv excision repair system. Excision repair after combined treatments was estimated by unscheduled DNA synthesis, BrdUrd photolysis, and the loss of sites sensitive to a uv specific endonuclease. Since the repair of damage from uv and its mimetics is coordinately controlled we expected that there would be similar rate-limiting steps in the repair of uv and chemical damage and that after a combined treatment the total amount of repair would be the same as from uv or the chemicals separately. The expectation was not fulfilled. In normal cells repair after a combined treatment was additive whereas in XP cells repair after a combined treatment was usually less than after either agent separately. The chemicals tested were AAAF, DMBA-epoxide, 4NQO, and ICR-170

Action observation and robotic agents: learning and anthropomorphism.

Science.gov (United States)

Press, Clare

2011-05-01

The 'action observation network' (AON), which is thought to translate observed actions into motor codes required for their execution, is biologically tuned: it responds more to observation of human, than non-human, movement. This biological specificity has been taken to support the hypothesis that the AON underlies various social functions, such as theory of mind and action understanding, and that, when it is active during observation of non-human agents like humanoid robots, it is a sign of ascription of human mental states to these agents. This review will outline evidence for biological tuning in the AON, examining the features which generate it, and concluding that there is evidence for tuning to both the form and kinematic profile of observed movements, and little evidence for tuning to belief about stimulus identity. It will propose that a likely reason for biological tuning is that human actions, relative to non-biological movements, have been observed more frequently while executing corresponding actions. If the associative hypothesis of the AON is correct, and the network indeed supports social functioning, sensorimotor experience with non-human agents may help us to predict, and therefore interpret, their movements. Copyright © 2011 Elsevier Ltd. All rights reserved.

Raising agents: sources of human social intelligence

NARCIS (Netherlands)

Hofstede, G.J.

2014-01-01

This paper urges that if we wish to give social intelligence to our agents, it pays to look at how we acquired our social intelligence ourselves. Our drives and motives are innate and deeply social. Next, as children we are social-ized to acquire norms and values. This motivational and group-based

The institutional stance in agent-based simulations

NARCIS (Netherlands)

Sileno, G.; Boer, A.; van Engers, T.; Filipe, J.; Fred, A.L.N.

2013-01-01

This paper presents a multi-agent framework intended to animate scenarios of compliance and non-compliance in a normative system. With the purpose of describing social human behaviour, we choose to reduce social complexity by creating models of the involved agents starting from stories, and

Intelligent virtual agents as language trainers facilitate multilingualism.

Science.gov (United States)

Macedonia, Manuela; Groher, Iris; Roithmayr, Friedrich

2014-01-01

intelligent virtual agents (IVAs) with human appearance and the capability to teach foreign language vocabulary. We report results from studies that we have conducted with Billie, an IVA employed as a vocabulary trainer, as well as research findings on the acceptance of the agent as a trainer by adults and children. The results show that Billie can train humans as well as a human teacher can and that both adults and children accept the IVA as a trainer. The advantages of IVAs are multiple. First, their teaching methods can be based on neuropsychological research findings concerning memory and learning practice. Second, virtual teachers can provide individualized training. Third, they coach users during training, are always supportive, and motivate learners to train. Fourth, agents will reside in the user's mobile devices and thus be at the user's disposal everywhere and anytime. Agents in apps will make foreign language training accessible to anybody at low cost. This will enable people around the world, including physically, financially, and geographically disadvantaged persons, to learn a foreign language and help to facilitate multilingualism.

Conversational Agents, Humorous Act Construction, and Social Intelligence

NARCIS (Netherlands)

Nijholt, Antinus; Dautenhahn, K.

2005-01-01

Humans use humour to ease communication problems in human-human interaction and in a similar way humour can be used to solve communication problems that arise with human-computer interaction. We discuss the role of embodied conversational agents in human-computer interaction and we have observations

An experimental study of the diagnosing value to nude mice model of transplanted human gastric cancer with folate-receptor MR contrast agent

International Nuclear Information System (INIS)

Ding Jianhui; Zeng Mengsu; Zhou Kangrong; Shen Jizhang; Chen Caizhong; Zhong Gaoren; Xue Qiong; Gu Haiyan

2005-01-01

Objective: To evaluate the tumor targeting characteristic by observing signal varying of human gastric cancer transplanted nude mice (SGC-7901 ) using Folate-Receptor MR contrast agent. Methods: As a Folate-Receptor MR contrast agent, Gd-DTPA-Folate was obtained by conjugation of DTPA-Folate and GdCl 3 under specific conditions. Nude mice of subcutaneously transplanted human gastric cancer (SGC-7901) were used as animal models, 12 mice were divided into experimental group (n=6) and control group (n=6) randomly. Both were injected with Gd-DTPA-Folate and Gd-DTPA (contained same gadolinium) via abdominal cavity respectively. Tumor signal varying was observed by T 1 WI after injection of contrast agent immediately, 1, 2, 3, 4, 6, 12 and 24 h, and tumor signal changing of experimental group was compared with that of control group. CNR (contrast noise ratio) was regarded as evaluating mark. Results: Tumor signal intensity of experimental group was increased evidently between 1-2 hours after injecting Gd-DTPA-Folate. Comparison with pre-injection, there was a significant difference (evaluating mark is CNR: q 1 =5.80, q 2 =4.64; P 1 =0.64, q 2 =1.19, P>0.05). Conclusion: Gd-DTPA-Folate shows definite characteristic of tumor targeting effect to nude mice of subcutaneously transplanted human gastric cancer (SGC-7901). (authors)

Empirical agent-based modelling challenges and solutions

CERN Document Server

Barreteau, Olivier

2014-01-01

This instructional book showcases techniques to parameterise human agents in empirical agent-based models (ABM). In doing so, it provides a timely overview of key ABM methodologies and the most innovative approaches through a variety of empirical applications.  It features cutting-edge research from leading academics and practitioners, and will provide a guide for characterising and parameterising human agents in empirical ABM.  In order to facilitate learning, this text shares the valuable experiences of other modellers in particular modelling situations. Very little has been published in the area of empirical ABM, and this contributed volume will appeal to graduate-level students and researchers studying simulation modeling in economics, sociology, ecology, and trans-disciplinary studies, such as topics related to sustainability. In a similar vein to the instruction found in a cookbook, this text provides the empirical modeller with a set of 'recipes'  ready to be implemented. Agent-based modeling (AB...

The Human Ureaplasma Species as Causative Agents of Chorioamnionitis.

Science.gov (United States)

Sweeney, Emma L; Dando, Samantha J; Kallapur, Suhas G; Knox, Christine L

2017-01-01

The human Ureaplasma species are the most frequently isolated microorganisms from the amniotic fluid and placentae of women who deliver preterm and are also associated with spontaneous abortions or miscarriages, neonatal respiratory diseases, and chorioamnionitis. Despite the fact that these microorganisms have been habitually found within placentae of pregnancies with chorioamnionitis, the role of Ureaplasma species as a causative agent has not been satisfactorily explained. There is also controversy surrounding their role in disease, particularly as not all women infected with Ureaplasma spp. develop chorioamnionitis. In this review, we provide evidence that Ureaplasma spp. are associated with diseases of pregnancy and discuss recent findings which demonstrate that Ureaplasma spp. are associated with chorioamnionitis, regardless of gestational age at the time of delivery. Here, we also discuss the proposed major virulence factors of Ureaplasma spp., with a focus on the multiple-banded antigen (MBA), which may facilitate modulation/alteration of the host immune response and potentially explain why only subpopulations of infected women experience adverse pregnancy outcomes. The information presented within this review confirms that Ureaplasma spp. are not simply "innocent bystanders" in disease and highlights that these microorganisms are an often underestimated pathogen of pregnancy. Copyright © 2016 American Society for Microbiology.

Teamwork in Multi-Agent Systems A Formal Approach

CERN Document Server

Dunin-Keplicz, Barbara Maria

2010-01-01

What makes teamwork tick?. Cooperation matters, in daily life and in complex applications. After all, many tasks need more than a single agent to be effectively performed. Therefore, teamwork rules!. Teams are social groups of agents dedicated to the fulfilment of particular persistent tasks. In modern multiagent environments, heterogeneous teams often consist of autonomous software agents, various types of robots and human beings. Teamwork in Multi-agent Systems: A Formal Approach explains teamwork rules in terms of agents' attitudes and their complex interplay. It provides the first comprehe

DNA repair in mammalian cells exposed to combinations of carcinogenic agents

International Nuclear Information System (INIS)

Setlow, R.B.; Ahmed, F.E.

1979-01-01

Cells defective in one or more aspects of repair are killed and often mutagenized more readily than normal cells by DNA damaging agents, and humans whose cells are deficient in repair are at an increased carcinogenic risk compared to normal individuals. The excision repair of uv induced pyrimidine dimers is a well studied system, but the details of the steps in this repair system are far from being understood in human cells. We know that there are a number of chemicals that mimic uv in that normal human cells repair DNA damage from both these agents and from uv by a long patch excision repair system, and that xeroderma pigmentosum cells defective in repair of uv are also defective in the repair of damage from these chemicals. The chemicals we have investigated are AAAF, 4-NQO, DMBA-epoxide, and ICR-170. We describe experiments, using several techniques, in which DNA excision repair is measured after treatment of various human cell strains with combinations of uv and these agents. If two agents have a common rate limiting step then, at doses high enough to saturate the repair system, one would expect the observed repair after a treatment with a combination of agents to be equal to that from one agent alone. Such is not the case for normal human or excision-deficient XP cells. In the former repair is additive and in the latter repair is usually appreciably less than that observed with either agent alone. Models that attempt to explain these surprising results involve complexes of enzymes and cofactors

The dynamic influence of human resources on evidence-based intervention sustainability and population outcomes: an agent-based modeling approach.

Science.gov (United States)

McKay, Virginia R; Hoffer, Lee D; Combs, Todd B; Margaret Dolcini, M

2018-06-05

Sustaining evidence-based interventions (EBIs) is an ongoing challenge for dissemination and implementation science in public health and social services. Characterizing the relationship among human resource capacity within an agency and subsequent population outcomes is an important step to improving our understanding of how EBIs are sustained. Although human resource capacity and population outcomes are theoretically related, examining them over time within real-world experiments is difficult. Simulation approaches, especially agent-based models, offer advantages that complement existing methods. We used an agent-based model to examine the relationships among human resources, EBI delivery, and population outcomes by simulating provision of an EBI through a hypothetical agency and its staff. We used data from existing studies examining a widely implemented HIV prevention intervention to inform simulation design, calibration, and validity. Once we developed a baseline model, we used the model as a simulated laboratory by systematically varying three human resource variables: the number of staff positions, the staff turnover rate, and timing in training. We tracked the subsequent influence on EBI delivery and the level of population risk over time to describe the overall and dynamic relationships among these variables. Higher overall levels of human resource capacity at an agency (more positions) led to more extensive EBI delivery over time and lowered population risk earlier in time. In simulations representing the typical human resource investments, substantial influences on population risk were visible after approximately 2 years and peaked around 4 years. Human resources, especially staff positions, have an important impact on EBI sustainability and ultimately population health. A minimum level of human resources based on the context (e.g., size of the initial population and characteristics of the EBI) is likely needed for an EBI to have a meaningful impact on

Federalism, Education-Related Public Good and Growth when Agents are Heterogeneou

OpenAIRE

Floriana Cerniglia; Riccarda Longaretti

2008-01-01

In this paper we use an endogeneous-growth model with human capital and heterogeneous agents to analyse the relationship between fiscal federalism and economic growth. Results show that federalism, which allows education-related public good levels to be tailored on the human capital of heterogeneous agents, increases human capital accumulation. This in turn leads to higher rates of growth. The benefits of federalism are stronger the larger the intra-jurisdiction variance of agents’ human capi...

Development of {sup 68}Ga-labeled mannosylated human serum albumin (MSA) as a lymph node imaging agent for positron emission tomography

Energy Technology Data Exchange (ETDEWEB)

Choi, Jae Yeon [Department of Nuclear Medicine, Institute of Radiation Medicine, Seoul National University College of Medicine, Seoul (Korea, Republic of); Cancer Research Institute, Seoul National University College of Medicine, Seoul (Korea, Republic of); Department of Radiation Applied Life Sciences, Seoul National University College of Medicine, Seoul (Korea, Republic of); Jeong, Jae Min, E-mail: jmjng@snu.ac.k [Department of Nuclear Medicine, Institute of Radiation Medicine, Seoul National University College of Medicine, Seoul (Korea, Republic of); Cancer Research Institute, Seoul National University College of Medicine, Seoul (Korea, Republic of); Department of Radiation Applied Life Sciences, Seoul National University College of Medicine, Seoul (Korea, Republic of); Yoo, Byong Chul [Research Institute, National Cancer Center, Goyang, Gyeonggi (Korea, Republic of); Kim, Kyunggon; Kim, Youngsoo [Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul (Korea, Republic of); Yang, Bo Yeun; Lee, Yun-Sang; Lee, Dong Soo [Department of Nuclear Medicine, Institute of Radiation Medicine, Seoul National University College of Medicine, Seoul (Korea, Republic of); Department of Radiation Applied Life Sciences, Seoul National University College of Medicine, Seoul (Korea, Republic of); Chung, June-Key [Department of Nuclear Medicine, Institute of Radiation Medicine, Seoul National University College of Medicine, Seoul (Korea, Republic of); Cancer Research Institute, Seoul National University College of Medicine, Seoul (Korea, Republic of); Department of Radiation Applied Life Sciences, Seoul National University College of Medicine, Seoul (Korea, Republic of); Lee, Myung Chul [Department of Nuclear Medicine, Institute of Radiation Medicine, Seoul National University College of Medicine, Seoul (Korea, Republic of)

2011-04-15

Introduction: Although many sentinel lymph node (SLN) imaging agents labeled with {sup 99m}Tc have been developed, no positron-emitting agent has been specifically designed for SLN imaging. Furthermore, the development of the beta probe and the requirement for better image resolution have increased the need for a positron-emitting SLN imaging agent. Here, we describe the development of a novel positron-emitting SLN imaging agent labeled with {sup 68}Ga. Methods: A mannosylated human serum albumin (MSA) was synthesized by conjugating {alpha}-D-mannopyranosylphenyl isothiocyanate to human serum albumin in sodium carbonate buffer (pH 9.5), and then 2-(p-isothiocyanatobenzyl)-1,4,7-triazacyclononane-1,4,7-triacetic acid was conjugated to synthesize NOTA-MSA. Numbers of mannose and NOTA units conjugated in NOTA-MSA were determined by matrix-assisted laser desorption ionization time-of-flight mass spectrometry. NOTA-MSA was labeled with {sup 68}Ga at room temperature. The stability of {sup 68}Ga-NOTA-MSA was checked in labeling medium at room temperature and in human serum at 37{sup o}C. Biodistribution in normal ICR mice was investigated after tail vein injection, and micro-positron emission tomography (PET) images were obtained after injecting {sup 68}Ga-NOTA-MSA into a tail vein or a footpad. Results: The numbers of conjugated {alpha}-D-mannopyranosylphenyl isothiocyanate and 2-(p-isothiocyanatobenzyl)-1,4,7-triazacyclononane-1,4,7-triacetic acid units in NOTA-MSA were 10.6 and 6.6, respectively. The labeling efficiency of {sup 68}Ga-NOTA-MSA was greater than 99% at room temperature, and its stability was greater than 99% at 4 h. Biodistribution and micro-PET studies of {sup 68}Ga-NOTA-MSA showed high liver and spleen uptakes after intravenous injection. {sup 68}Ga-NOTA-MSA injected into a footpad rapidly migrated to the lymph node. Conclusions: {sup 68}Ga-NOTA-MSA was successfully developed as a novel SLN imaging agent for PET. NOTA-MSA is easily labeled at high

An in vitro and in vivo evaluation of the efficacy of recombinant human liver prolidase as a catalytic bioscavenger of chemical warfare nerve agents.

Science.gov (United States)

Rezk, Peter E; Zdenka, Pierre; Sabnekar, Praveena; Kajih, Takwen; Mata, David G; Wrobel, Chester; Cerasoli, Douglas M; Chilukuri, Nageswararao

2015-01-01

In this study, we determined the ability of recombinant human liver prolidase to hydrolyze nerve agents in vitro and its ability to afford protection in vivo in mice. Using adenovirus containing the human liver prolidase gene, the enzyme was over expressed by 200- to 300-fold in mouse liver and purified to homogeneity by affinity and gel filtration chromatography. The purified enzyme hydrolyzed sarin, cyclosarin and soman with varying rates of hydrolysis. The most efficient hydrolysis was with sarin, followed by soman and by cyclosarin {apparent kcat/Km [(1.9 ± 0.3), (1.7 ± 0.2), and (0.45 ± 0.04)] × 10(5 )M(-1 )min(-1), respectively}; VX and tabun were not hydrolyzed by the recombinant enzyme. The enzyme hydrolyzed P (+) isomers faster than the P (-) isomers. The ability of recombinant human liver prolidase to afford 24 hour survival against a cumulative dose of 2 × LD50 of each nerve agent was investigated in mice. Compared to mice injected with a control virus, mice injected with the prolidase expressing virus contained (29 ± 7)-fold higher levels of the enzyme in their blood on day 5. Challenging these mice with two consecutive 1 × LD50 doses of sarin, cyclosarin, and soman resulted in the death of all animals within 5 to 8 min from nerve agent toxicity. In contrast, mice injected with the adenovirus expressing mouse butyrylcholinesterase, an enzyme which is known to afford protection in vivo, survived multiple 1 × LD50 challenges of these nerve agents and displayed no signs of toxicity. These results suggest that, while prolidase can hydrolyze certain G-type nerve agents in vitro, the enzyme does not offer 24 hour protection against a cumulative dose of 2 × LD50 of G-agents in mice in vivo.

Parasites and other infectious agents in marine finfish and shellfish species posing a hazard to human health (ToR b)

DEFF Research Database (Denmark)

Alfjorden, A.; Podolska, M.; Karaseva, T.

2015-01-01

Several parasites and other infectious agents frequently reported by the WGPDMO in the annual update of disease trends (ICES WGPDMO reports 1999–2015) have the potential to be harmful to human health if ingested in unprocessed or inadequate-ly/partly processed seafood. These include, but are not ...

Barnase as a new therapeutic agent triggering apoptosis in human cancer cells.

Directory of Open Access Journals (Sweden)

Evelina Edelweiss

Full Text Available BACKGROUND: RNases are currently studied as non-mutagenic alternatives to the harmful DNA-damaging anticancer drugs commonly used in clinical practice. Many mammalian RNases are not potent toxins due to the strong inhibition by ribonuclease inhibitor (RI presented in the cytoplasm of mammalian cells. METHODOLOGY/PRINCIPAL FINDINGS: In search of new effective anticancer RNases we studied the effects of barnase, a ribonuclease from Bacillus amyloliquefaciens, on human cancer cells. We found that barnase is resistant to RI. In MTT cell viability assay, barnase was cytotoxic to human carcinoma cell lines with half-inhibitory concentrations (IC(50 ranging from 0.2 to 13 microM and to leukemia cell lines with IC(50 values ranging from 2.4 to 82 microM. Also, we characterized the cytotoxic effects of barnase-based immunoRNase scFv 4D5-dibarnase, which consists of two barnase molecules serially fused to the single-chain variable fragment (scFv of humanized antibody 4D5 that recognizes the extracellular domain of cancer marker HER2. The scFv 4D5-dibarnase specifically bound to HER2-positive cells and was internalized via receptor-mediated endocytosis. The intracellular localization of internalized scFv 4D5-dibarnase was determined by electronic microscopy. The cytotoxic effect of scFv 4D5-dibarnase on HER2-positive human ovarian carcinoma SKOV-3 cells (IC(50 = 1.8 nM was three orders of magnitude greater than that of barnase alone. Both barnase and scFv 4D5-dibarnase induced apoptosis in SKOV-3 cells accompanied by internucleosomal chromatin fragmentation, membrane blebbing, the appearance of phosphatidylserine on the outer leaflet of the plasma membrane, and the activation of caspase-3. CONCLUSIONS/SIGNIFICANCE: These results demonstrate that barnase is a potent toxic agent for targeting to cancer cells.

Embodied agents in virtual environments: The Aveiro project

NARCIS (Netherlands)

Leiviska, K.; Heylen, Dirk K.J.; Nijholt, Antinus; Poel, Mannes

2001-01-01

We present current and envisaged work on the AVEIRO project of our research group concerning virtual environments inhabited by autonomous embodied agents. These environments are being built for researching issues in human-computer interactions and intelligent agent applications. We describe the

An Exception Handling Service for Software Agent Ensembles

National Research Council Canada - National Science Library

Klein, Mark

2004-01-01

... (I) the creation of better contingent contracts between agents (both human and software- based) as well as (2) exception-handling agents that monitor MAS for problem symptoms, diagnose the underlying problems, and intervene as appropriate to avoid or resolve these problems.

Reliability of plant root comet assay in comparison with human leukocyte comet assay for assessment environmental genotoxic agents.

Science.gov (United States)

Reis, Gabriela Barreto Dos; Andrade-Vieira, Larissa Fonseca; Moraes, Isabella de Campos; César, Pedro Henrique Souza; Marcussi, Silvana; Davide, Lisete Chamma

2017-08-01

Comet assay is an efficient test to detect genotoxic compounds based on observation of DNA damage. The aim of this work was to compare the results obtained from the comet assay in two different type of cells extracted from the root tips from Lactuca sativa L. and human blood. For this, Spent Pot Liner (SPL), and its components (aluminum and fluoride) were applied as toxic agents. SPL is a solid waste generated in industry from the aluminum mining and processing with known toxicity. Three concentrations of all tested solutions were applied and the damages observed were compared to negative and positive controls. It was observed an increase in the frequency of DNA damage for human leukocytes and plant cells, in all treatments. On human leukocytes, SPL induced the highest percentage of damage, with an average of 87.68%. For root tips cells of L. sativa the highest percentage of damage was detected for aluminum (93.89%). Considering the arbitrary units (AU), the average of nuclei with high levels of DNA fragmentation was significant for both cells type evaluated. The tested cells demonstrated equal effectiveness for detection of the genotoxicity induced by the SPL and its chemical components, aluminum and fluoride. Further, using a unique method, the comet assay, we proved that cells from root tips of Lactuca sativa represent a reliable model to detect DNA damage induced by genotoxic pollutants is in agreement of those observed in human leukocytes as model. So far, plant cells may be suggested as important system to assess the toxicological risk of environmental agents. Copyright © 2017 Elsevier Inc. All rights reserved.

Emotional Storytelling using Virtual and Robotic Agents

OpenAIRE

Costa, Sandra; Brunete, Alberto; Bae, Byung-Chull; Mavridis, Nikolaos

2016-01-01

In order to create effective storytelling agents three fundamental questions must be answered: first, is a physically embodied agent preferable to a virtual agent or a voice-only narration? Second, does a human voice have an advantage over a synthesised voice? Third, how should the emotional trajectory of the different characters in a story be related to a storyteller's facial expressions during storytelling time, and how does this correlate with the apparent emotions on the faces of the list...

New approaches to assessing the effects of mutagenic agents on the integrity of the human genome

International Nuclear Information System (INIS)

Elespuru, R.K.; Sankaranarayanan, K.

2007-01-01

Heritable genetic alterations, although individually rare, have a substantial collective health impact. Approximately 20% of these are new mutations of unknown cause. Assessment of the effect of exposures to DNA damaging agents, i.e. mutagenic chemicals and radiations, on the integrity of the human genome and on the occurrence of genetic disease remains a daunting challenge. Recent insights may explain why previous examination of human exposures to ionizing radiation, as in Hiroshima and Nagasaki, failed to reveal heritable genetic effects. New opportunities to assess the heritable genetic damaging effects of environmental mutagens are afforded by: (1) integration of knowledge on the molecular nature of genetic disorders and the molecular effects of mutagens; (2) the development of more practical assays for germline mutagenesis; (3) the likely use of population-based genetic screening in personalized medicine

Intelligent Virtual Agents as Language Trainers Facilitate Multilingualism

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Manuela eMacedonia

2014-04-01

Full Text Available In this paper we introduce a new generation of language trainers: intelligent virtual agents (IVAs with human appearance and the capability to teach foreign language vocabulary. We report results from studies that we have conducted with Billie, an IVA employed as a vocabulary trainer, as well as research findings on the acceptance of the agent as a trainer by adults and children. The results show that Billie can train humans as well as a human teacher can and that both adults and children accept the IVA as a trainer. The advantages of IVAs are multiple. First, their teaching methods can be based on neuropsychological research findings concerning memory and learning practice. Second, virtual teachers can provide individualized training. Third, they coach users during training, are always supportive, and motivate learners to train. Fourth, agents will reside in the user’s mobile devices and thus be at the user’s disposal everywhere and anytime. Agents in apps will make foreign language training accessible to anybody at low cost. This will enable people around the world, including physically, financially and geographically disadvantaged persons, to learn a foreign language and help to facilitate multilingualism.

Novel targeted agents for gastric cancer

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Liu Lian

2012-06-01

Full Text Available Abstract Contemporary advancements have had little impact on the treatment of gastric cancer (GC, the world’s second highest cause of cancer death. Agents targeting human epidermal growth factor receptor mediated pathways have been a common topic of contemporary cancer research, including monoclonal antibodies (mAbs and receptor tyrosine kinase inhibitors (TKIs. Trastuzumab is the first target agent evidencing improvements in overall survival in HER2-positive (human epidermal growth factor receptor 2 gastric cancer patients. Agents targeting vascular epithelial growth factor (VEGF, mammalian target of rapamycin (mTOR, and other biological pathways are also undergoing clinical trials, with some marginally positive results. Effective targeted therapy requires patient selection based on predictive molecular biomarkers. Most phase III clinical trials are carried out without patient selection; therefore, it is hard to achieve personalized treatment and to monitor patient outcome individually. The trend for future clinical trials requires patient selection methods based on current understanding of GC biology with the application of biomarkers.

AN INTELLIGENT CONVERSATION AGENT FOR HEALTH CARE DOMAIN

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K. Karpagam

2014-04-01

Full Text Available Human Computer Interaction is one of the pervasive application areas of computer science to develop with multimodal interaction for information sharings. The conversation agent acts as the major core area for developing interfaces between a system and user with applied AI for proper responses. In this paper, the interactive system plays a vital role in improving knowledge in the domain of health through the intelligent interface between machine and human with text and speech. The primary aim is to enrich the knowledge and help the user in the domain of health using conversation agent to offer immediate response with human companion feel.

Theoretical foundations for the responsibility of autonomous agents

NARCIS (Netherlands)

Hage, Jaap

This article argues that it is possible to hold autonomous agents themselves, and not only their makers, users or owners, responsible for the acts of these agents. In this connection autonomous systems are computer programs that interact with the outside world without human interference. They

Emotion in reinforcement learning agents and robots: A survey

OpenAIRE

Moerland, T.M.; Broekens, D.J.; Jonker, C.M.

2018-01-01

This article provides the first survey of computational models of emotion in reinforcement learning (RL) agents. The survey focuses on agent/robot emotions, and mostly ignores human user emotions. Emotions are recognized as functional in decision-making by influencing motivation and action selection. Therefore, computational emotion models are usually grounded in the agent's decision making architecture, of which RL is an important subclass. Studying emotions in RL-based agents is useful for ...

A Framework For Agent-Based Educational Guidance And ...

African Journals Online (AJOL)

This work applies principles of artificial intelligence and agent development of educational guidance and counselling. An agent – based expert system is developed. The system supports the storage and intelligent interactive processing of the knowledge acquired by study and experience of the human expert in the domain ...

Avaliação clínica e molecular de cães com erliquiose Clinical and molecular evaluation of dogs with ehrlichiosis

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Valéria Régia Franco Sousa

2010-06-01

Full Text Available A erliquiose monocítica canina é uma doença cosmopolita causada por Ehrlichia canis e transmitida pelo carrapato Rhipicephalus sanguineus, sendo frequentemente diagnosticada em cães em todo o Brasil. Este trabalho teve por objetivo investigar citológica e molecularmente a infecção por Ehrlichia em 195 cães atendidos no Hospital Veterinário da Universidade Federal de Mato Grosso, analisando os achados clínicos e laboratoriais. Nos 48 cães atendidos com citologia positiva para Ehrlichia sp., foi possível verificar a diversidade de sinais, com predominância estatisticamente significativa de palidez de mucosas (P≤0,05, assim como variados achados hematológicos, ocorrendo tanto anemia, leucopenia e trombocitopenia, quanto normalidade ou aumento dessas células. Ocorreu aumento das proteínas plasmáticas, com hiperglobulinemia, sem, no entanto, haver diferença significativa (P≥0,05, apesar de esse achado ser frequente nessa afecção. Por meio do PCR nested, confirmou-se a infecção por E. canis em cães da cidade de Cuiabá.The canine monocytic ehrlichiosis is a cosmopolitan disease, caused by Ehrlichia canis, transmitted by ticks Rhipicephalus sanguineus that has been frequently diagnosed in dogs throughout the country. This study aimed to investigate the cytological and molecular Ehrlichia infection in 195 dogs examined at the University Veterinary Hospital of Mato Grosso, by analyzing the clinical and laboratory findings. In 48 dogs with positive cytology for Ehrlichia sp it was possible to detect the diversity of signs, with predominance statistically significant of pallor of mucous membranes (P≤0.05 as well as several hematological findings, occurring anemia, leukopenia and thrombocytopenia, or increased as normal cells. There was increased of plasma proteins, with hyperglobulinemia, however without any significant difference (P≥0.05, although this finding is common in that infection. Through the nested PCR technique it

Solution NMR Structures of Oxidized and Reduced Ehrlichia chaffeensis thioredoxin: NMR-Invisible Structure Owing to Backbone Dynamics

Energy Technology Data Exchange (ETDEWEB)

Buchko, Garry W.; Hewitt, Stephen N.; Van Voorhis, Wesley C.; Myler, Peter J.

2018-01-02

Thioredoxins (Trxs) are small ubiquitous proteins that participate in a diverse variety of redox reactions via the reversible oxidation of two cysteine thiol groups in a structurally conserved active site, CGPC. Here, we describe the NMR solution structures of a Trx from Ehrlichia chaffeensis (Ec-Trx, ECH_0218), the etiological agent responsible for human monocytic ehrlichiosis, in both the oxidized and reduced states. The overall topology of the calculated structures is similar in both redox states and similar to other Trx structures, a five-strand, mixed -sheet (1:3:2:4:5) surrounded by four -helices. Unlike other Trxs studied by NMR in both redox states, the 1H-15N HSQC spectra of reduced Ec-Trx was missing eight amide cross peaks relative to the spectra of oxidized Ec-Trx. These missing amides correspond to residues C32-E39 in the active site containing helix (2) and S72-I75 in a loop near the active site and suggest a substantial change in the backbone dynamics associated with the formation of an intramolecular C32-C35 disulfide bond.

Emotion in reinforcement learning agents and robots : A survey

NARCIS (Netherlands)

Moerland, T.M.; Broekens, D.J.; Jonker, C.M.

2018-01-01

This article provides the first survey of computational models of emotion in reinforcement learning (RL) agents. The survey focuses on agent/robot emotions, and mostly ignores human user emotions. Emotions are recognized as functional in decision-making by influencing motivation and action

Effects of cytochalasin congeners, microtubule-directed agents, and doxorubicin alone or in combination against human ovarian carcinoma cell lines in vitro

International Nuclear Information System (INIS)

Trendowski, Matthew; Christen, Timothy D.; Acquafondata, Christopher; Fondy, Thomas P.

2015-01-01

Although the actin cytoskeleton is vital for carcinogenesis and subsequent pathology, no microfilament-directed agent has been approved for cancer chemotherapy. One of the most studied classes of microfilament-directed agents has been the cytochalasins, mycotoxins known to disrupt the formation of actin polymers. In the present study, we sought to determine the effects of cytochalasin congeners toward human drug sensitive and multidrug resistant cell lines. SKOV3 human ovarian carcinoma and several multidrug resistant derivatives were tested for sensitivity against a panel of nine cytochalasin congeners, as well as three clinically approved chemotherapeutic agents (doxorubicin, paclitaxel, and vinblastine). In addition, verapamil, a calcium ion channel blocker known to reverse P-glycoprotein (P-gp) mediated drug resistance, was used in combination with multiple cytochalasin congeners to determine whether drug sensitivity could be increased. While multidrug resistant SKVLB1 had increased drug tolerance (was more resistant) to most cytochalasin congeners in comparison to drug sensitive SKOV3, the level of resistance was 10 to 1000-fold less for the cytochalasins than for any of the clinically approved agents. While cytochalasins did not appear to alter the expression of ATP binding cassette (ABC) transporters, several cytochalasins appeared to inhibit the activity of ABC transporter-mediated efflux of rhodamine 123 (Rh123), suggesting that these congeners do have affinity for drug efflux pumps. Cytochalasins also appeared to significantly decrease the F/G-actin ratio in both drug sensitive and drug resistant cells, indicative of marked microfilament inhibition. The cytotoxicity of most cytochalasin congeners could be increased with the addition of verapamil, and the drug sensitivity of resistant SKVLB1 to the clinically approved antineoplastic agents could be increased with the addition of cytochalasins. As assessed by isobolographic analysis and Chou

Construction of a Learning Agent Handling Its Rewards According to Environmental Situations

Science.gov (United States)

Moriyama, Koichi; Numao, Masayuki

The authors aim at constructing an agent which learns appropriate actions in a Multi-Agent environment with and without social dilemmas. For this aim, the agent must have nonrationality that makes it give up its own profit when it should do that. Since there are many studies on rational learning that brings more and more profit, it is desirable to utilize them for constructing the agent. Therefore, we use a reward-handling manner that makes internal evaluation from the agent's rewards, and then the agent learns actions by a rational learning method with the internal evaluation. If the agent has only a fixed manner, however, it does not act well in the environment with and without dilemmas. Thus, the authors equip the agent with several reward-handling manners and criteria for selecting an effective one for the environmental situation. In the case of humans, what generates the internal evaluation is usually called emotion. Hence, this study also aims at throwing light on emotional activities of humans from a constructive view. In this paper, we divide a Multi-Agent environment into three situations and construct an agent having the reward-handling manners and the criteria. We observe that the agent acts well in all the three Multi-Agent situations composed of homogeneous agents.

A phenanthrene derived PARP inhibitor is an extra-centrosomes de-clustering agent exclusively eradicating human cancer cells

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Izraeli Shai

2011-09-01

Full Text Available Abstract Background Cells of most human cancers have supernumerary centrosomes. To enable an accurate chromosome segregation and cell division, these cells developed a yet unresolved molecular mechanism, clustering their extra centrosomes at two poles, thereby mimicking mitosis in normal cells. Failure of this bipolar centrosome clustering causes multipolar spindle structures and aberrant chromosomes segregation that prevent normal cell division and lead to 'mitotic catastrophe cell death'. Methods We used cell biology and biochemical methods, including flow cytometry, immunocytochemistry and live confocal imaging. Results We identified a phenanthrene derived PARP inhibitor, known for its activity in neuroprotection under stress conditions, which exclusively eradicated multi-centrosomal human cancer cells (mammary, colon, lung, pancreas, ovarian while acting as extra-centrosomes de-clustering agent in mitosis. Normal human proliferating cells (endothelial, epithelial and mesenchymal cells were not impaired. Despite acting as PARP inhibitor, the cytotoxic activity of this molecule in cancer cells was not attributed to PARP inhibition alone. Conclusion We identified a water soluble phenanthridine that exclusively targets the unique dependence of most human cancer cells on their supernumerary centrosomes bi-polar clustering for their survival. This paves the way for a new selective cancer-targeting therapy, efficient in a wide range of human cancers.

Nontherapeutic Use of Antimicrobial Agents in Animal Agriculture: Implications for Pediatrics.

Science.gov (United States)

Paulson, Jerome A; Zaoutis, Theoklis E

2015-12-01

Antimicrobial resistance is one of the most serious threats to public health globally and threatens our ability to treat infectious diseases. Antimicrobial-resistant infections are associated with increased morbidity, mortality, and health care costs. Infants and children are affected by transmission of susceptible and resistant food zoonotic pathogens through the food supply, direct contact with animals, and environmental pathways. The overuse and misuse of antimicrobial agents in veterinary and human medicine is, in large part, responsible for the emergence of antibiotic resistance. Approximately 80% of the overall tonnage of antimicrobial agents sold in the United States in 2012 was for animal use, and approximately 60% of those agents are considered important for human medicine. Most of the use involves the addition of low doses of antimicrobial agents to the feed of healthy animals over prolonged periods to promote growth and increase feed efficiency or at a range of doses to prevent disease. These nontherapeutic uses contribute to resistance and create new health dangers for humans. This report describes how antimicrobial agents are used in animal agriculture, reviews the mechanisms of how such use contributes to development of resistance, and discusses US and global initiatives to curb the use of antimicrobial agents in agriculture. Copyright © 2015 by the American Academy of Pediatrics.

Agent-Based Models in Social Physics

Science.gov (United States)

Quang, Le Anh; Jung, Nam; Cho, Eun Sung; Choi, Jae Han; Lee, Jae Woo

2018-06-01

We review the agent-based models (ABM) on social physics including econophysics. The ABM consists of agent, system space, and external environment. The agent is autonomous and decides his/her behavior by interacting with the neighbors or the external environment with the rules of behavior. Agents are irrational because they have only limited information when they make decisions. They adapt using learning from past memories. Agents have various attributes and are heterogeneous. ABM is a non-equilibrium complex system that exhibits various emergence phenomena. The social complexity ABM describes human behavioral characteristics. In ABMs of econophysics, we introduce the Sugarscape model and the artificial market models. We review minority games and majority games in ABMs of game theory. Social flow ABM introduces crowding, evacuation, traffic congestion, and pedestrian dynamics. We also review ABM for opinion dynamics and voter model. We discuss features and advantages and disadvantages of Netlogo, Repast, Swarm, and Mason, which are representative platforms for implementing ABM.

Sensitization of human cells by inhibitors of DNA synthesis following the action of DNA-damaging agents

Energy Technology Data Exchange (ETDEWEB)

Filatov, M.V.; Noskin, L.A. (Leningrad Inst. of Nuclear Physics, Gatchina (USSR))

1983-08-01

Inhibitors of DNA synthesis 1-..beta..-arabinofuranosylcytosine (Ac) and hydroxyurea (Hu) taken together drastically sensitized human cells to the killing effect of DNA-damaging agents. For UV-irradiation this sensitization depended on the cells' ability for excision repair. By using viscoelastometric methods of measurement of double-strand breaks (DSB) in the genome, it was established that the first DSB were generated after incubation of the damaged cells in the mixture of inhibitors at about the same dose when sensitization appeared. A scheme is proposed to describe molecular events associated with the phenomenon studied. 35 refs.

Social scaling of extrapersonal space: target objects are judged as closer when the reference frame is a human agent with available movement potentialities.

Science.gov (United States)

Fini, C; Brass, M; Committeri, G

2015-01-01

Space perception depends on our motion potentialities and our intended actions are affected by space perception. Research on peripersonal space (the space in reaching distance) shows that we perceive an object as being closer when we (Witt, Proffitt, & Epstein, 2005; Witt & Proffitt, 2008) or another actor (Costantini, Ambrosini, Sinigaglia, & Gallese, 2011; Bloesch, Davoli, Roth, Brockmole, & Abrams, 2012) can interact with it. Similarly, an object only triggers specific movements when it is placed in our peripersonal space (Costantini, Ambrosini, Tieri, Sinigaglia, & Committeri, 2010) or in the other's peripersonal space (Costantini, Committeri, & Sinigaglia, 2011; Cardellicchio, Sinigaglia, & Costantini, 2013). Moreover, also the extrapersonal space (the space outside reaching distance) seems to be perceived in relation to our movement capabilities: the more effort it takes to cover a distance, the greater we perceive the distance to be (Proffitt, Stefanucci, Banton, & Epstein, 2003; Sugovic & Witt, 2013). However, not much is known about the influence of the other's movement potentialities on our extrapersonal space perception. Three experiments were carried out investigating the categorization of distance in extrapersonal space using human or non-human allocentric reference frames (RF). Subjects were asked to judge the distance ("Near" or "Far") of a target object (a beach umbrella) placed at progressively increasing or decreasing distances until a change from near to far or vice versa was reported. In the first experiment we found a significant "Near space extension" when the allocentric RF was a human virtual agent instead of a static, inanimate object. In the second experiment we tested whether the "Near space extension" depended on the anatomical structure of the RF or its movement potentialities by adding a wooden dummy. The "Near space extension" was only observed for the human agent but not for the dummy. Finally, to rule out the possibility that the

Behavioral biometrics for verification and recognition of malicious software agents

Science.gov (United States)

Yampolskiy, Roman V.; Govindaraju, Venu

2008-04-01

Homeland security requires technologies capable of positive and reliable identification of humans for law enforcement, government, and commercial applications. As artificially intelligent agents improve in their abilities and become a part of our everyday life, the possibility of using such programs for undermining homeland security increases. Virtual assistants, shopping bots, and game playing programs are used daily by millions of people. We propose applying statistical behavior modeling techniques developed by us for recognition of humans to the identification and verification of intelligent and potentially malicious software agents. Our experimental results demonstrate feasibility of such methods for both artificial agent verification and even for recognition purposes.

Evolutionary Agent-Based Simulation of the Introduction of New Technologies in Air Traffic Management

Science.gov (United States)

Yliniemi, Logan; Agogino, Adrian K.; Tumer, Kagan

2014-01-01

Accurate simulation of the effects of integrating new technologies into a complex system is critical to the modernization of our antiquated air traffic system, where there exist many layers of interacting procedures, controls, and automation all designed to cooperate with human operators. Additions of even simple new technologies may result in unexpected emergent behavior due to complex human/ machine interactions. One approach is to create high-fidelity human models coming from the field of human factors that can simulate a rich set of behaviors. However, such models are difficult to produce, especially to show unexpected emergent behavior coming from many human operators interacting simultaneously within a complex system. Instead of engineering complex human models, we directly model the emergent behavior by evolving goal directed agents, representing human users. Using evolution we can predict how the agent representing the human user reacts given his/her goals. In this paradigm, each autonomous agent in a system pursues individual goals, and the behavior of the system emerges from the interactions, foreseen or unforeseen, between the agents/actors. We show that this method reflects the integration of new technologies in a historical case, and apply the same methodology for a possible future technology.

Chemical warfare agent simulants for human volunteer trials of emergency decontamination: A systematic review.

Science.gov (United States)

James, Thomas; Wyke, Stacey; Marczylo, Tim; Collins, Samuel; Gaulton, Tom; Foxall, Kerry; Amlôt, Richard; Duarte-Davidson, Raquel

2018-01-01

Incidents involving the release of chemical agents can pose significant risks to public health. In such an event, emergency decontamination of affected casualties may need to be undertaken to reduce injury and possible loss of life. To ensure these methods are effective, human volunteer trials (HVTs) of decontamination protocols, using simulant contaminants, have been conducted. Simulants must be used to mimic the physicochemical properties of more harmful chemicals, while remaining non-toxic at the dose applied. This review focuses on studies that employed chemical warfare agent simulants in decontamination contexts, to identify those simulants most suitable for use in HVTs of emergency decontamination. Twenty-two simulants were identified, of which 17 were determined unsuitable for use in HVTs. The remaining simulants (n = 5) were further scrutinized for potential suitability according to toxicity, physicochemical properties and similarities to their equivalent toxic counterparts. Three suitable simulants, for use in HVTs were identified; methyl salicylate (simulant for sulphur mustard), diethyl malonate (simulant for soman) and malathion (simulant for VX or toxic industrial chemicals). All have been safely used in previous HVTs, and have a range of physicochemical properties that would allow useful inference to more toxic chemicals when employed in future studies of emergency decontamination systems. © 2017 Crown Copyright. Journal of Applied Toxicology published by John Wiley & Sons, Ltd.

How gestures affect students: A comparative experiment using class presentations conducted by an anthropomorphic agent

Science.gov (United States)

Shirakawa, Tomohiro; Sato, Hiroshi; Imao, Tomoya

2017-07-01

Recently, a variety of user interfaces have been developed based on human-robot and human-agent interaction, and anthropomorphic agents are used as one type of interface. However, the use of anthropomorphic agents is applied mainly to the medical and cognitive sciences, and there are few studies of their application to other fields. Therefore, we used an anthropomorphic agent of MMD in a virtual lecture to analyze the effect of gestures on students and search for ways to apply anthropomorphic agents to the field of educational technology.

Effects of treatment with antimicrobial agents on the human colonic microflora

OpenAIRE

Rafii, Fatemeh

2008-01-01

Fatemeh Rafii, John B Sutherland, Carl E CernigliaDivision of Microbiology, National Center for Toxicological Research, FDA, Jefferson, AR, USAAbstract: Antimicrobial agents are the most valuable means available for treating bacterial infections. However, the administration of therapeutic doses of antimicrobial agents to patients is a leading cause of disturbance of the normal gastrointestinal microflora. This disturbance results in diminishing the natural defense mechanisms provided by the c...

An Agent-Based Modeling Framework for Simulating Human Exposure to Environmental Stresses in Urban Areas

Directory of Open Access Journals (Sweden)

Liang Emlyn Yang

2018-04-01

Full Text Available Several approaches have been used to assess potential human exposure to environmental stresses and achieve optimal results under various conditions, such as for example, for different scales, groups of people, or points in time. A thorough literature review in this paper identifies the research gap regarding modeling approaches for assessing human exposure to environment stressors, and it indicates that microsimulation tools are becoming increasingly important in human exposure assessments of urban environments, in which each person is simulated individually and continuously. The paper further describes an agent-based model (ABM framework that can dynamically simulate human exposure levels, along with their daily activities, in urban areas that are characterized by environmental stresses such as air pollution and heat stress. Within the framework, decision-making processes can be included for each individual based on rule-based behavior in order to achieve goals under changing environmental conditions. The ideas described in this paper are implemented in a free and open source NetLogo platform. A basic modeling scenario of the ABM framework in Hamburg, Germany, demonstrates its utility in various urban environments and individual activity patterns, as well as its portability to other models, programs, and frameworks. The prototype model can potentially be extended to support environmental incidence management through exploring the daily routines of different groups of citizens, and comparing the effectiveness of different strategies. Further research is needed to fully develop an operational version of the model.

Sporothrix chilensis sp. nov. (Ascomycota: Ophiostomatales), a soil-borne agent of human sporotrichosis with mild-pathogenic potential to mammals.

Science.gov (United States)

Rodrigues, Anderson Messias; Cruz Choappa, Rodrigo; Fernandes, Geisa Ferreira; de Hoog, G Sybren; de Camargo, Zoilo Pires

2016-02-01

A combination of phylogeny, evolution, morphologies and ecologies has enabled major advances in understanding the taxonomy of Sporothrix species, including members exhibiting distinct lifestyles such as saprobes, human/animal pathogens, and insect symbionts. Phylogenetic analyses of ITS1/2 + 5.8s sequences split Sporothrix genus in two well-defined groups with dissimilar ecologies. Species embedded in the Sporothrix schenckii complex are frequently agents of human and animal sporotrichosis, and some of these are responsible for large sapronoses and zoonoses around the warmer temperate regions of the world. At the other extreme, basal saprophytic species evolved in association with decaying wood and soil, and are rarely found to cause human disease. We propose to create a new taxa, Sporothrix chilensis sp. nov., to accommodate strains collected from a clinical case of onychomycosis as well as from environmental origins in Chile. Multigene analyses based on ITS1/2 + 5.8s region, beta-tubulin, calmodulin and translation elongation factor 1α revealed that S. chilensis is a member of the Sporothrix pallida complex, and the nearest taxon is Sporothrix mexicana, a rare soil-borne species, non-pathogenic to humans. The ITS region serves as a primary barcode marker, while each one of the protein-coding loci easily recognized species boundaries providing sufficient information for species identification. A disseminated model of murine sporotrichosis revealed a mild-pathogenic potential, with lung invasion. Although S. chilensis is not a primary pathogen, accidental infection may have an impact in the immunosuppressed population. With the introduction of distinct species with similar routes of transmission but different virulence, identification of Sporothrix agents at the species level is mandatory. Copyright © 2015 The British Mycological Society. Published by Elsevier Ltd. All rights reserved.

An Emotional Agent Model Based on Granular Computing

Directory of Open Access Journals (Sweden)

Jun Hu

2012-01-01

Full Text Available Affective computing has a very important significance for fulfilling intelligent information processing and harmonious communication between human being and computers. A new model for emotional agent is proposed in this paper to make agent have the ability of handling emotions, based on the granular computing theory and the traditional BDI agent model. Firstly, a new emotion knowledge base based on granular computing for emotion expression is presented in the model. Secondly, a new emotional reasoning algorithm based on granular computing is proposed. Thirdly, a new emotional agent model based on granular computing is presented. Finally, based on the model, an emotional agent for patient assistant in hospital is realized, experiment results show that it is efficient to handle simple emotions.

Environmental and chemotherapeutic agents induce breakage at genes involved in leukemia-causing gene rearrangements in human hematopoietic stem/progenitor cells

Energy Technology Data Exchange (ETDEWEB)

Thys, Ryan G., E-mail: rthys@wakehealth.edu [Department of Cancer Biology, Wake Forest School of Medicine, Medical Center Boulevard, Winston-Salem, NC 27157-1016 (United States); Lehman, Christine E., E-mail: clehman@wakehealth.edu [Department of Cancer Biology, Wake Forest School of Medicine, Medical Center Boulevard, Winston-Salem, NC 27157-1016 (United States); Pierce, Levi C.T., E-mail: Levipierce@gmail.com [Human Longevity, Inc., San Diego, California 92121 (United States); Wang, Yuh-Hwa, E-mail: yw4b@virginia.edu [Department of Biochemistry and Molecular Genetics, University of Virginia, 1340 Jefferson Park Avenue, Charlottesville, VA 22908-0733 (United States)

2015-09-15

Highlights: • Environmental/chemotherapeutic agents cause DNA breakage in MLL and CBFB in HSPCs. • Diethylnitrosamine-induced DNA breakage at MLL and CBFB shown for the first time. • Chemical-induced DNA breakage occurs at topoisomerase II cleavage sites. • Chemical-induced DNA breaks display a pattern similar to those in leukemia patients. • Long-term exposures suggested to generate DNA breakage at leukemia-related genes. - Abstract: Hematopoietic stem and progenitor cells (HSPCs) give rise to all of the cells that make up the hematopoietic system in the human body, making their stability and resilience especially important. Damage to these cells can severely impact cell development and has the potential to cause diseases, such as leukemia. Leukemia-causing chromosomal rearrangements have largely been studied in the context of radiation exposure and are formed by a multi-step process, including an initial DNA breakage and fusion of the free DNA ends. However, the mechanism for DNA breakage in patients without previous radiation exposure is unclear. Here, we investigate the role of non-cytotoxic levels of environmental factors, benzene, and diethylnitrosamine (DEN), and chemotherapeutic agents, etoposide, and doxorubicin, in generating DNA breakage at the patient breakpoint hotspots of the MLL and CBFB genes in human HSPCs. These conditions represent exposure to chemicals encountered daily or residual doses from chemotherapeutic drugs. Exposure of HSPCs to non-cytotoxic levels of environmental chemicals or chemotherapeutic agents causes DNA breakage at preferential sites in the human genome, including the leukemia-related genes MLL and CBFB. Though benzene, etoposide, and doxorubicin have previously been linked to leukemia formation, this is the first study to demonstrate a role for DEN in the generation of DNA breakage at leukemia-specific sites. These chemical-induced DNA breakpoints coincide with sites of predicted topoisomerase II cleavage. The

Environmental and chemotherapeutic agents induce breakage at genes involved in leukemia-causing gene rearrangements in human hematopoietic stem/progenitor cells

International Nuclear Information System (INIS)

Thys, Ryan G.; Lehman, Christine E.; Pierce, Levi C.T.; Wang, Yuh-Hwa

2015-01-01

Highlights: • Environmental/chemotherapeutic agents cause DNA breakage in MLL and CBFB in HSPCs. • Diethylnitrosamine-induced DNA breakage at MLL and CBFB shown for the first time. • Chemical-induced DNA breakage occurs at topoisomerase II cleavage sites. • Chemical-induced DNA breaks display a pattern similar to those in leukemia patients. • Long-term exposures suggested to generate DNA breakage at leukemia-related genes. - Abstract: Hematopoietic stem and progenitor cells (HSPCs) give rise to all of the cells that make up the hematopoietic system in the human body, making their stability and resilience especially important. Damage to these cells can severely impact cell development and has the potential to cause diseases, such as leukemia. Leukemia-causing chromosomal rearrangements have largely been studied in the context of radiation exposure and are formed by a multi-step process, including an initial DNA breakage and fusion of the free DNA ends. However, the mechanism for DNA breakage in patients without previous radiation exposure is unclear. Here, we investigate the role of non-cytotoxic levels of environmental factors, benzene, and diethylnitrosamine (DEN), and chemotherapeutic agents, etoposide, and doxorubicin, in generating DNA breakage at the patient breakpoint hotspots of the MLL and CBFB genes in human HSPCs. These conditions represent exposure to chemicals encountered daily or residual doses from chemotherapeutic drugs. Exposure of HSPCs to non-cytotoxic levels of environmental chemicals or chemotherapeutic agents causes DNA breakage at preferential sites in the human genome, including the leukemia-related genes MLL and CBFB. Though benzene, etoposide, and doxorubicin have previously been linked to leukemia formation, this is the first study to demonstrate a role for DEN in the generation of DNA breakage at leukemia-specific sites. These chemical-induced DNA breakpoints coincide with sites of predicted topoisomerase II cleavage. The

Richard Bradley: a unified, living agent theory of the cause of infectious diseases of plants, animals, and humans in the first decades of the 18th century.

Science.gov (United States)

Santer, Melvin

2009-01-01

During the years 1714 to 1721, Richard Bradley, who was later to become the first Professor of Botany at Cambridge University, proposed a unified, unique, living agent theory of the cause of infectious diseases of plants and animals and the plague of humans. Bradley's agents included microscopic organisms, revealed by the studies of Robert Hooke and Antony van Leeuwenhoek. His theory derived from his experimental studies of plants and their diseases and from microscopic observation of animalcules in different naturally occurring and artificial environments. He concluded that there was a microscopic world of "insects" that lived and reproduced under the appropriate conditions, and that infectious diseases of plants were caused by such "insects." Since there are structural and functional similarities between plants and animals, Bradley concluded that microscopic organisms caused human and animal infectious diseases as well. However, his living agent cause of infectious diseases was not accepted by the contemporary scientific society.

Cooperation in human-computer communication

OpenAIRE

Kronenberg, Susanne

2000-01-01

The goal of this thesis is to simulate cooperation in human-computer communication to model the communicative interaction process of agents in natural dialogs in order to provide advanced human-computer interaction in that coherence is maintained between contributions of both agents, i.e. the human user and the computer. This thesis contributes to certain aspects of understanding and generation and their interaction in the German language. In spontaneous dialogs agents cooperate by the pro...

Military chemical warfare agent human subjects testing: part 2--long-term health effects among participants of U.S. military chemical warfare agent testing.

Science.gov (United States)

Brown, Mark

2009-10-01

Military chemical warfare agent testing from World War I to 1975 produced thousands of veterans with concerns about how their participation affected their health. A companion article describes the history of these experiments, and how the lack of clinical data hampers evaluation of long-term health consequences. Conversely, much information is available about specific agents tested and their long-term health effects in other populations, which may be invaluable for helping clinicians respond effectively to the health care and other needs of affected veterans. The following review describes tested agents and their known long-term health consequences. Although hundreds of chemicals were tested, they fall into only about a half-dozen pharmaceutical classes, including common pharmaceuticals; anticholinesterase agents including military nerve agents and pesticides; anticholinergic glycolic acid esters such as atropine; acetylcholine reactivators such as 2-PAM; psychoactive compounds including cannabinoids, phencyclidine, and LSD; and irritants including tear gas and riot control agents.

Esters of Bendamustine Are by Far More Potent Cytotoxic Agents than the Parent Compound against Human Sarcoma and Carcinoma Cells.

Directory of Open Access Journals (Sweden)

Stefan Huber

Full Text Available The alkylating agent bendamustine is approved for the treatment of hematopoietic malignancies such as non-Hodgkin lymphoma, chronic lymphocytic leukemia and multiple myeloma. As preliminary data on recently disclosed bendamustine esters suggested increased cytotoxicity, we investigated representative derivatives in more detail. Especially basic esters, which are positively charged under physiological conditions, were in the crystal violet and the MTT assay up to approximately 100 times more effective than bendamustine, paralleled by a higher fraction of early apoptotic cancer cells and increased expression of p53. Analytical studies performed with bendamustine and representative esters revealed pronounced cellular accumulation of the derivatives compared to the parent compound. In particular, the pyrrolidinoethyl ester showed a high enrichment in tumor cells and inhibition of OCT1- and OCT3-mediated transport processes, suggesting organic cation transporters to be involved. However, this hypothesis was not supported by the differential expression of OCT1 (SLC22A1 and OCT3 (SLC22A3, comparing a panel of human cancer cells. Bendamustine esters proved to be considerably more potent cytotoxic agents than the parent compound against a broad panel of human cancer cell types, including hematologic and solid malignancies (e.g. malignant melanoma, colorectal carcinoma and lung cancer, which are resistant to bendamustine. Interestingly, spontaneously immortalized human keratinocytes, as a model of "normal" cells, were by far less sensitive than tumor cells against the most potent bendamustine esters.

Nootropic agents stimulate neurogenesis. Brain Cells, Inc.: WO2007104035.

Science.gov (United States)

Taupin, Philippe

2009-05-01

The application is in the field of adult neurogenesis, neural stem cells and cellular therapy. It aims to characterize the activity of nootropic agents on adult neurogenesis in vitro. Nootropic agents are substances improving cognitive and mental abilities. AMPA (alpha-amino-3-hydroxyl-5-methyl-4-isoxazole-propionate) and nootropic agents were assessed for the potential to differentiate human neural progenitor and stem cells into neuronal cells in vitro. They were also tested for their behavioural activity on the novel object recognition task. AMPA, piracetam, FK-960 and SGS-111 induce and stimulate neuronal differentiation of human-derived neural progenitor and stem cells. SGS-111 increases the number of visits to the novel object. The neurogenic activity of piracetam and SGS-111 is mediated through AMPA receptor. The neurogenic activity of SGS-111 may contribute and play a role in its nootropic activity. These results suggest that nootropic agents may elicit some of their effects through their neurogenic activity. The application claims the use of nootropic agents for their neurogenic activity and for the treatment of neurological diseases, disorders and injuries, by stimulating or increasing the generation of neuronal cells in the adult brain.

Online Bahavior Aquisition of an Agent based on Coaching as Learning Assistance

Science.gov (United States)

Hirokawa, Masakazu; Suzuki, Kenji

This paper describes a novel methodology, namely ``Coaching'', which allows humans to give a subjective evaluation to an agent in an iterative manner. This is an interactive learning method to improve the reinforcement learning by modifying a reward function dynamically according to given evaluations by a trainer and the learning situation of the agent. We demonstrate that the agent can learn different reward functions by given instructions such as ``good or bad'' by human's observation, and can also obtain a set of behavior based on the learnt reward functions through several experiments.

Human and Virtual Agents Interacting in the Virtuality Continuum

NARCIS (Netherlands)

Nijholt, Antinus

2004-01-01

In this paper we take a multi-party interaction point of view on our research on multimodal interactions between agents in various virtual environments: an educational environment, a meeting environment, and a storytelling environment. These environments are quite different. All these environments

The influence of a bystander agent's beliefs on children's and adults' decision-making process.

Science.gov (United States)

Buttelmann, Frances; Buttelmann, David

2017-01-01

The ability to attribute and represent others' mental states (e.g., beliefs; so-called "theory of mind") is essential for participation in human social interaction. Despite a considerable body of research using tasks in which protagonists in the participants' attentional focus held false or true beliefs, the question of automatic belief attribution to bystander agents has received little attention. In the current study, we presented adults and 6-year-olds (N=92) with an implicit computer-based avoidance false-belief task in which participants were asked to place an object into one of three boxes. While doing so, we manipulated the beliefs of an irrelevant human-like or non-human-like bystander agent who was visible on the screen. Importantly, the bystander agent's beliefs were irrelevant for solving the task. Still, children's decision making was significantly influenced by the bystander agent's beliefs even if this was a non-human-like self-propelled object. Such an influence did not become obvious in adults' deliberate decisions but occurred only in their reaction times, which suggests that they also processed the bystander agent's beliefs but were able to suppress the influence of such beliefs on their behavior regulation. The results of a control study (N=53) ruled out low-level explanations and confirmed that self-propelledness of agents is a necessary factor for belief attribution to occur. Thus, not only do humans spontaneously ascribe beliefs to self-propelled bystander agents, but those beliefs even influence meaningful decisions in children. Copyright © 2016 Elsevier Inc. All rights reserved.

Interface technology based on human cognition and understanding for the operation and maintenance of advanced human cooperative plants

International Nuclear Information System (INIS)

Numano, Masayoshi; Niwa, Yasuyuki; Itoh, Hiroko; Miyazaki, Keiko; Fukuto, Junji; Okazaki, Tadatsugi; Matsukura, Hiroshi; Tanaka, Kunihiko; Matsuoka, Takeshi; Liu, Qiao; Mitomo, Nobuo

2006-01-01

'Development of Intelligent Systems Technology for Advanced Human Cooperative Plants' was implemented as 'Nuclear Energy Fundamentals Crossover Research' by 3 institutes (The Institute of Physical and Chemical Research; RIKEN, National Institute of Advanced Industrial Science and Technology; AIST and National Maritime Research Institute; NMRI). Aiming at appropriate interaction between human and agents in Digital Maintenance Field which spreads widely in time and space, NMRI developed technologies on contraction of plant information, generalization and intuition of the information through visual presentation. Intuitive presentation gave on-site information for identifying the source of abnormalities to human operators. And a human-machine cooperation infrastructure for plant maintenance was proposed and developed, where an overview display was used to show position and state information of all the agents in the plant and each agent view was used to show the corresponding agent's information in detail. A part of this technology was implemented in a demonstration program. Two agents were developed to support human operators' plant maintenance activities in this program. This demonstration showed the effectiveness of human-agent cooperation for early plant abnormality detection. (author)

The role of the oximes HI-6 and HS-6 inside human acetylcholinesterase inhibited with nerve agents: a computational study.

Science.gov (United States)

Cuya, Teobaldo; Gonçalves, Arlan da Silva; da Silva, Jorge Alberto Valle; Ramalho, Teodorico C; Kuca, Kamil; C C França, Tanos

2017-10-27

The oximes 4-carbamoyl-1-[({2-[(E)-(hydroxyimino) methyl] pyridinium-1-yl} methoxy) methyl] pyridinium (known as HI-6) and 3-carbamoyl-1-[({2-[(E)-(hydroxyimino) methyl] pyridinium-1-yl} methoxy) methyl] pyridinium (known as HS-6) are isomers differing from each other only by the position of the carbamoyl group on the pyridine ring. However, this slight difference was verified to be responsible for big differences in the percentual of reactivation of acetylcholinesterase (AChE) inhibited by the nerve agents tabun, sarin, cyclosarin, and VX. In order to try to find out the reason for this, a computational study involving molecular docking, molecular dynamics, and binding energies calculations, was performed on the binding modes of HI-6 and HS-6 on human AChE (HssAChE) inhibited by those nerve agents.

A Watershed-Scale Agent-Based Model Incorporating Agent Learning and Interaction of Farmers' Decisions Subject to Carbon and Miscanthus Prices

Science.gov (United States)

Ng, T.; Eheart, J.; Cai, X.; Braden, J. B.

2010-12-01

Agricultural watersheds are coupled human-natural systems where the land use decisions of human agents (farmers) affect surface water quality, and in turn, are affected by the weather and yields. The reliable modeling of such systems requires an approach that considers both the human and natural aspects. Agent-based modeling (ABM), representing the human aspect, coupled with hydrologic modeling, representing the natural aspect, is one such approach. ABM is a relatively new modeling paradigm that formulates the system from the perspectives of the individual agents, i.e., each agent is modeled as a discrete autonomous entity with distinct goals and actions. The primary objective of this study is to demonstrate the applicability of this approach to agricultural watershed management. This is done using a semi-hypothetical case study of farmers in the Salt Creek watershed in East-Central Illinois under the influence markets for carbon and second-generation bioenergy crop (specifically, miscanthus). An agent-based model of the system is developed and linked to a hydrologic model of the watershed. The former is based on fundamental economic and mathematical programming principles, while the latter is based on the Soil and Water Assessment Tool (SWAT). Carbon and second-generation bioenergy crop markets are of interest here due to climate change and energy independence concerns. The agent-based model is applied to fifty hypothetical heterogeneous farmers. The farmers' decisions depend on their perceptions of future conditions. Those perceptions are updated, according to a pre-defined algorithm, as the farmers make new observations of prices, costs, yields and the weather with time. The perceptions are also updated as the farmers interact with each other as they share new information on initially unfamiliar activities (e.g., carbon trading, miscanthus cultivation). The updating algorithm is set differently for different farmers such that each is unique in his processing of

Fuzzy Constraint-Based Agent Negotiation

Institute of Scientific and Technical Information of China (English)

Menq-Wen Lin; K. Robert Lai; Ting-Jung Yu

2005-01-01

Conflicts between two or more parties arise for various reasons and perspectives. Thus, resolution of conflicts frequently relies on some form of negotiation. This paper presents a general problem-solving framework for modeling multi-issue multilateral negotiation using fuzzy constraints. Agent negotiation is formulated as a distributed fuzzy constraint satisfaction problem (DFCSP). Fuzzy constrains are thus used to naturally represent each agent's desires involving imprecision and human conceptualization, particularly when lexical imprecision and subjective matters are concerned. On the other hand, based on fuzzy constraint-based problem-solving, our approach enables an agent not only to systematically relax fuzzy constraints to generate a proposal, but also to employ fuzzy similarity to select the alternative that is subject to its acceptability by the opponents. This task of problem-solving is to reach an agreement that benefits all agents with a high satisfaction degree of fuzzy constraints, and move towards the deal more quickly since their search focuses only on the feasible solution space. An application to multilateral negotiation of a travel planning is provided to demonstrate the usefulness and effectiveness of our framework.

The distribution of alternative agents for targeted radiotherapy within human neuroblastoma spheroids

International Nuclear Information System (INIS)

Mairs, R.J.; Gaze, M.N.; Murray, T.; Reid, R.; McSharry, C.; Babich, J.W.

1991-01-01

This study aims to select the radiopharmaceutical vehicle for targeted radiotherapy of neuroblastoma which is most likely to penetrate readily the centre of micrometastases in vivo. The human neuroblastoma cell line NB1-G, grown as multicellular spheroids provided an in vitro model for micrometastases. The radiopharmaceuticals studied were the catecholamine analogue metaiodobenzyl guanidine (mIBG), a specific neuroectodermal monoclonal antibody (UJ13A) and β nerve growth factor (βNGF). Following incubation of each drug with neuroblastoma spheroids, autoradiographs of frozen sections were prepared to demonstrate their relative distributions. mIBG and βNGF were found to penetrate the centre of spheroids readily although the concentration of mIBG greatly exceeded that of βNGF. In contrast, UJ13A was only bound peripherally. We conclude that mIBG is the best available vehicle for targeted radiotherapy of neuroblastoma cells with active uptake mechanisms for catecholimines. It is suggested that radionuclides with a shorter range of emissions than 131 I may be conjugated to benzyl guanidine to constitute more effective targeting agents with potentially less toxicity to adjacent normal tissues. (author)

Human Respiratory Syncytial Virus and Human Metapneumovirus

OpenAIRE

Luciana Helena Antoniassi da Silva; Fernando Rosado Spilki; Adriana Gut Lopes Riccetto; Emilio Elias Baracat; Clarice Weis Arns

2009-01-01

The human respiratory syncytial virus (hRSV) and the human metapneumovírus (hMPV) are main etiological agents of acute respiratory infections (ARI). The ARI is an important cause of childhood morbidity and mortality worldwide.  hRSV and hMPV are members of the Paramyxoviridae. They are enveloped, non-segmented viruses, with negative-sense single stranded genomes. Respiratory syncytial virus (hRSV) is the best characterized agent viral of this group, associated with respiratory diseases in...

An experimental comparison of path planning techniques applied to micro-sized magnetic agents

NARCIS (Netherlands)

Scheggi, Stefano; Misra, Sarthak; Haliyo, S.; Sill, A.; Regnier, S.; Fatikow, S.

2016-01-01

Micro-sized agents can be used in applications suchas microassembly, micromanipulation, and minimally invasive surgeries. Magnetic agents such as paramagnetic microparticles can be controlled to deliver pharmaceutical agents to difficult-toaccess regions within the human body. In order to

Synthesis and Preclinical Characterization of a Cationic Iodinated Imaging Contrast Agent (CA4+) and Its Use for Quantitative Computed Tomography of Ex Vivo Human Hip Cartilage.

Science.gov (United States)

Stewart, Rachel C; Patwa, Amit N; Lusic, Hrvoje; Freedman, Jonathan D; Wathier, Michel; Snyder, Brian D; Guermazi, Ali; Grinstaff, Mark W

2017-07-13

Contrast agents that go beyond qualitative visualization and enable quantitative assessments of functional tissue performance represent the next generation of clinically useful imaging tools. An optimized and efficient large-scale synthesis of a cationic iodinated contrast agent (CA4+) is described for imaging articular cartilage. Contrast-enhanced CT (CECT) using CA4+ reveals significantly greater agent uptake of CA4+ in articular cartilage compared to that of similar anionic or nonionic agents, and CA4+ uptake follows Donnan equilibrium theory. The CA4+ CECT attenuation obtained from imaging ex vivo human hip cartilage correlates with the glycosaminoglycan content, equilibrium modulus, and coefficient of friction, which are key indicators of cartilage functional performance and osteoarthritis stage. Finally, preliminary toxicity studies in a rat model show no adverse events, and a pharmacokinetics study documents a peak plasma concentration 30 min after dosing, with the agent no longer present in vivo at 96 h via excretion in the urine.

42 CFR 60.36 - Consequence of using an agent.

Science.gov (United States)

2010-10-01

... 42 Public Health 1 2010-10-01 2010-10-01 false Consequence of using an agent. 60.36 Section 60.36 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES GRANTS HEALTH EDUCATION ASSISTANCE LOAN PROGRAM The Lender and Holder § 60.36 Consequence of using an agent. The delegation of...

Specific binding of prostaglandin E2 to membrane preparations from human skin: receptor modulation by UVB-irradiation and chemical agents

International Nuclear Information System (INIS)

Lord, J.T.; Ziboh, V.A.

1979-01-01

Human skin membranes bind prostaglandin E2 (PGE2) with high affinity and specificity. This binding is inhibited by trypsin or heat treatment suggesting that PGE2 receptors have protein components. Exposure of the membranes to ultraviolet irradiation (UVB) resulted in the loss of the membrane binding capacity for PGE2. This UVB-inhibitory effect could be prevented by a known protein sulfhydryl-oxidizing agent and a known lipid anti-oxidant

An Agent Model of Temporal Dynamics in Relapse and Recurrence in Depression

NARCIS (Netherlands)

Aziz, A.A.; Klein, M.C.A.; Treur, J.

2009-01-01

This paper presents a dynamic agent model of recurrences of a depression for an individual. Based on several personal characteristics and a representation of events (i.e. life events or daily hassles) the agent model can simulate whether a human agent that recovered from a depression will fall into

How turn-taking strategies influence users’ impressions of an agent

NARCIS (Netherlands)

ter Maat, Mark; Truong, Khiet Phuong; Heylen, Dirk K.J.; Allbeck, Jan; Badler, Norman; Bickmore, Timothy; Pelachaud, Catherine; Safonova, Alla

Different turn-taking strategies of an agent influence the impression that people have of it. We recorded conversations of a human with an interviewing agent, controlled by a wizard and using a particular turn-taking strategy. A questionnaire with 27 semantic differential scales concerning

Multi-Agent Model of Trust in a Human Game

NARCIS (Netherlands)

Bosse, T.; Jonker, C.M.; Meij, L. van der; Robu, V.; Treur, J.; Calisti, M.; Klusch, M.; Unland, R.

2005-01-01

This paper presents a System for Analysis of Multi-Issue Negotiation (SAMIN). The agents in this system conduct one-to-one negotiations, in which the values across multiple issues are negotiated on simultaneously. It is demonstrated how the system supports both automated negotiation (i.e., conducted

Humans as major geological and geomorphological agents in the Anthropocene: the significance of artificial ground in Great Britain.

Science.gov (United States)

Price, Simon J; Ford, Jonathan R; Cooper, Anthony H; Neal, Catherine

2011-03-13

Since the first prehistoric people started to dig for stone to make implements, rather than pick up loose material, humans have modified the landscape through excavation of rock and soil, generation of waste and creation of artificial ground. In Great Britain over the past 200 years, people have excavated, moved and built up the equivalent of at least six times the volume of Ben Nevis. It is estimated that the worldwide deliberate annual shift of sediment by human activity is 57,000 Mt (million tonnes) and exceeds that of transport by rivers to the oceans (22,000 Mt) almost by a factor of three. Humans sculpt and transform the landscape through the physical modification of the shape and properties of the ground. As such, humans are geological and geomorphological agents and the dominant factor in landscape evolution through settlement and widespread industrialization and urbanization. The most significant impact of this has been since the onset of the Industrial Revolution in the eighteenth century, coincident with increased release of greenhouse gases to the atmosphere. The anthropogenic sedimentological record, therefore, provides a marker on which to characterize the Anthropocene.

Evolvable Work-Practice Interfaces Between Humans and Agents, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — NASA science researchers and payload specialists will be supported in their tasks by increasingly complex computational components. Whether these are agents...

Functionalized Magnetic Resonance Contrast Agent Selectively Binds to Glycoprotein IIb/IIIa on Activated Human Platelets under Flow Conditions and Is Detectable at Clinically Relevant Field Strengths

Directory of Open Access Journals (Sweden)

Constantin von zur Mühlen

2008-03-01

Full Text Available Recent progress in molecular magnetic resonance imaging (MRI provides the opportunity to image cells and cellular receptors using microparticles of iron oxide (MPIOs. However, imaging targets on vessel walls remains challenging owing to the quantity of contrast agents delivered to areas of interest under shear stress conditions. We evaluated ex vivo binding characteristics of a functional MRI contrast agent to ligand-induced binding sites (LIBSs on activated glycoprotein IIb/IIIa receptors of human platelets, which were lining rupture-prone atherosclerotic plaques and could therefore facilitate detection of platelet-mediated pathology in atherothrombotic disease. MPIOs were conjugated to anti-LIBS single-chain antibodies (LIBS-MPIO or control antibodies (control MPIO. Ex vivo binding to human platelet-rich clots in a dose-dependent manner was confirmed on a 3 T clinical MRI scanner and by histology (p < .05 for LIBS-MPIO vs control MPIO. By using a flow chamber setup, significant binding of LIBS-MPIO to a platelet matrix was observed under venous and arterial flow conditions, but not for control MPIO (p < .001. A newly generated MRI contrast agent detects activated human platelets at clinically relevant magnetic field strengths and binds to platelets under venous and arterial flow conditions, conveying high payloads of contrast to specific molecular targets. This may provide the opportunity to identify vulnerable, rupture-prone atherosclerotic plaques via noninvasive MRI.

Gadolinium-porphyrins: new potential magnetic resonance imaging contrast agents for melanoma detection

Directory of Open Access Journals (Sweden)

Daryoush Shahbazi-Gahrouei

2006-11-01

Full Text Available BACKGROUND: Two new porphyrin-based magnetic resonance imaging (MRI contrast agents, Gd-hematoporphyrin (Gd-H and Gd-tetra-carboranylmethoxyphenyl-porphyrin (Gd-TCP were synthesized and tested in nude mice with human melanoma (MM-138 xenografts as new melanoma contrast agents. METHODS: Subcutaneous xenografts of human melanoma cells (MM-138 were studied in 30 (five groups of six nude mice. The effect of different contrast agents (Gd-TCP, Gd-H, GdCl3 and Gd-DTPA on proton relaxation times was measured in tumors and other organs. T1 values, signal enhancement and the Gd concentration for different contrast agent solutions were also investigated. RESULTS: The porphyrin agents showed higher relaxivity compared to the clincal agent, Gd-DTPA. A significant 16% and 21% modification in T1 relaxation time of the water in human melanoma tumors grafted in the nude mice was revealed 24 hours after injection of Gd-TCP and Gd-H, respectively. The percentage of injected Gd localized to the tumor measured by inductively coupled plasma atomic emission spectrometry (ICP-AES was approximately 21% for Gd-TCP and 28% for Gd-H which were higher than that of Gd-DTPA (10%. CONCLUSIONS: The high concentration of Gd in the tumor is indicative of a selective retention of the compounds and indicates that Gd-TCP and Gd-H are promising MR imaging contrast agents for melanoma detection. Gd-porphyrins have considerable promise for further diagnostic applications in magnetic resonance imaging. KEY WORDS: MRI, porphyrin-based contrast agent, hematoporphyrin, melanoma.

Activity of antiretroviral drugs in human infections by opportunistic agents

Directory of Open Access Journals (Sweden)

Izabel Galhardo Demarchi

2012-03-01

Full Text Available Highly active antiretroviral therapy (HAART is used in patients infected with HIV. This treatment has been shown to significantly decrease opportunist infections such as those caused by viruses, fungi and particularly, protozoa. The use of HAART in HIV-positive persons is associated with immune reconstitution as well as decreased prevalence of oral candidiasis and candidal carriage. Antiretroviral therapy benefits patients who are co-infected by the human immunodeficiency virus (HIV, human herpes virus 8 (HHV-8, Epstein-Barr virus, hepatitis B virus (HBV, parvovirus B19 and cytomegalovirus (CMV. HAART has also led to a significant reduction in the incidence, and the modification of characteristics, of bacteremia by etiological agents such as Staphylococcus aureus, coagulase negative staphylococcus, non-typhoid species of Salmonella, Streptococcus pneumoniae, Pseudomonas aeruginosa, and Mycobacterium tuberculosis. HAART can modify the natural history of cryptosporidiosis and microsporidiosis, and restore mucosal immunity, leading to the eradication of Cryptosporidium parvum. A similar restoration of immune response occurs in infections by Toxoplasma gondii. The decline in the incidence of visceral leishmaniasis/HIV co-infection can be observed after the introduction of protease inhibitor therapy. Current findings are highly relevant for clinical medicine and may serve to reduce the number of prescribed drugs thereby improving the quality of life of patients with opportunistic diseases.A terapia HAART (terapia antirretroviral altamente ativa é usada em pacientes infectados pelo vírus da imunodeficiência humana (HIV e demonstrou diminuição significativa de infecções oportunistas, tais como as causadas por vírus, fungos, protozoários e bactérias. O uso da HAART está associado com a reconstituição imunológica e diminuição na prevalência de candidíase oral. A terapia antirretroviral beneficia pacientes co-infectados pelo HIV, v

Younger and Older Users’ Recognition of Virtual Agent Facial Expressions

Science.gov (United States)

Beer, Jenay M.; Smarr, Cory-Ann; Fisk, Arthur D.; Rogers, Wendy A.

2015-01-01

As technology advances, robots and virtual agents will be introduced into the home and healthcare settings to assist individuals, both young and old, with everyday living tasks. Understanding how users recognize an agent’s social cues is therefore imperative, especially in social interactions. Facial expression, in particular, is one of the most common non-verbal cues used to display and communicate emotion in on-screen agents (Cassell, Sullivan, Prevost, & Churchill, 2000). Age is important to consider because age-related differences in emotion recognition of human facial expression have been supported (Ruffman et al., 2008), with older adults showing a deficit for recognition of negative facial expressions. Previous work has shown that younger adults can effectively recognize facial emotions displayed by agents (Bartneck & Reichenbach, 2005; Courgeon et al. 2009; 2011; Breazeal, 2003); however, little research has compared in-depth younger and older adults’ ability to label a virtual agent’s facial emotions, an import consideration because social agents will be required to interact with users of varying ages. If such age-related differences exist for recognition of virtual agent facial expressions, we aim to understand if those age-related differences are influenced by the intensity of the emotion, dynamic formation of emotion (i.e., a neutral expression developing into an expression of emotion through motion), or the type of virtual character differing by human-likeness. Study 1 investigated the relationship between age-related differences, the implication of dynamic formation of emotion, and the role of emotion intensity in emotion recognition of the facial expressions of a virtual agent (iCat). Study 2 examined age-related differences in recognition expressed by three types of virtual characters differing by human-likeness (non-humanoid iCat, synthetic human, and human). Study 2 also investigated the role of configural and featural processing as a

Assessing Consequential Scenarios in a Complex Operational Environment Using Agent Based Simulation

Science.gov (United States)

2017-03-16

capabilities and maturities of 4 subelements: cognition, judgment, emotion , and critical thinking. Each model represents these subelements differently...CADSIM) 102 5.2 Evaluating Agent-Based Technologies: Maturity Level and the Human Domain 103 5.2.1 Evaluation of Maturity Level 103 5.2.2 Human...describes the maturity of agent-based models, ranging from realistic caricatures to quantitatively characterized phenomena at the microlevel. This

In vitro efficiency and mechanistic role of indocyanine green as photodynamic therapy agent for human melanoma

Energy Technology Data Exchange (ETDEWEB)

Mamoon, A.M.; Miller, L.; Gamal-Eldeen, A. M.; Ruppel, M. E.; Smith, R. J.; Tsang, T.; Miller, L. M.

2009-05-02

Photodynamic therapy (PDT) is a promising treatment for superficial cancer. However, poor therapeutic results have been reported for melanoma, due to the high melanin content. Indocyanine green (ICG) has near infrared absorption (700-800 nm) and melanins do not absorb strongly in this area. This study explores the efficiency of ICG as a PDT agent for human melanoma, and its mechanistic role in the cell death pathway. Human skin melanoma cells (Sk-Mel-28) were incubated with ICG and exposed to a low power Ti:Sapphire laser. Synchrotron-assisted Fourier transform infrared microspectroscopy and hierarchical cluster analysis were used to assess the cell damage and changes in lipid, protein, and nucleic acids. The cell death pathway was determined by analysis of cell viability and apoptosis and necrosis markers. In the cell death pathway, {sup 1}O{sub 2} generation evoked rapid multiple consequences that trigger apoptosis after laser exposure for only 15min including the release of cytochrome c, the activation of total caspases, caspase-3, and caspase-9, the inhibition of NF-{Kappa}B P65, and the enhancement of DNA fragmentation, and histone acetylation. ICG/PDT can efficiently and rapidly induce apoptosis in human melanoma cells and it can be considered as a new therapeutic approach for topical treatment of melanoma.

Towards the Verification of Human-Robot Teams

Science.gov (United States)

Fisher, Michael; Pearce, Edward; Wooldridge, Mike; Sierhuis, Maarten; Visser, Willem; Bordini, Rafael H.

2005-01-01

Human-Agent collaboration is increasingly important. Not only do high-profile activities such as NASA missions to Mars intend to employ such teams, but our everyday activities involving interaction with computational devices falls into this category. In many of these scenarios, we are expected to trust that the agents will do what we expect and that the agents and humans will work together as expected. But how can we be sure? In this paper, we bring together previous work on the verification of multi-agent systems with work on the modelling of human-agent teamwork. Specifically, we target human-robot teamwork. This paper provides an outline of the way we are using formal verification techniques in order to analyse such collaborative activities. A particular application is the analysis of human-robot teams intended for use in future space exploration.

Overexpressed human metallothionein IIA gene protects Chinese hamster ovary cells from killing by alkylating agents

International Nuclear Information System (INIS)

Kaina, B.; Lohrer, H.; Karin, M.; Herrlich, P.

1990-01-01

Experiments were designed to detect survival advantages that cells gain by overexpressing metallothionein (MT). Chinese hamster ovary K1-2 cells and an x-ray-sensitive derivative were transfected with a bovine papillomavirus (BPV)-linked construct carrying the human metallothionein IIA (hMT-IIA) gene. Transfectants survived 40-fold higher levels of cadmium chloride, harbored at least 30 copies of hMT-IIA, and contained 25- to 166-fold more MT than the parent cells. Even under conditions of reduced glutathione synthesis, the transfectants were not more resistant to the lethal effects of ionizing radiation and bleomycin than the parent cells. Thus free radicals generated by these agents cannot be scavenged efficiently by MT in vivo. The hMT-IIA transfectants, however, but not control transfectants harboring a BPV-MT promoter-neo construct, tolerated significantly higher doses of the alkylating agents N-methyl-N-nitrosourea and N-methyl-N'-nitro-N-nitrosoguanidine. Resistance and MT overexpression occurred irrespective of selection and cultivation in cadmium and zinc. There was no increase in resistance to methyl methanesulfonate and N-hydroxyethyl-N-chloroethylnitrosourea. MT did not affect the degree of overall DNA methylation after N-methyl-N-nitrosourea treatment nor the level of O6-methylguanine-DNA methyltransferase. The results suggest that MT participates as a cofactor or regulatory element in repair or tolerance of toxic alkylation lesions

Overexpressed human metallothionein IIA gene protects Chinese hamster ovary cells from killing by alkylating agents

Energy Technology Data Exchange (ETDEWEB)

Kaina, B.; Lohrer, H.; Karin, M.; Herrlich, P. (Kernforschungszentrum Karlsruhe, Karlsruhe (Germany, F.R.))

1990-04-01

Experiments were designed to detect survival advantages that cells gain by overexpressing metallothionein (MT). Chinese hamster ovary K1-2 cells and an x-ray-sensitive derivative were transfected with a bovine papillomavirus (BPV)-linked construct carrying the human metallothionein IIA (hMT-IIA) gene. Transfectants survived 40-fold higher levels of cadmium chloride, harbored at least 30 copies of hMT-IIA, and contained 25- to 166-fold more MT than the parent cells. Even under conditions of reduced glutathione synthesis, the transfectants were not more resistant to the lethal effects of ionizing radiation and bleomycin than the parent cells. Thus free radicals generated by these agents cannot be scavenged efficiently by MT in vivo. The hMT-IIA transfectants, however, but not control transfectants harboring a BPV-MT promoter-neo construct, tolerated significantly higher doses of the alkylating agents N-methyl-N-nitrosourea and N-methyl-N'-nitro-N-nitrosoguanidine. Resistance and MT overexpression occurred irrespective of selection and cultivation in cadmium and zinc. There was no increase in resistance to methyl methanesulfonate and N-hydroxyethyl-N-chloroethylnitrosourea. MT did not affect the degree of overall DNA methylation after N-methyl-N-nitrosourea treatment nor the level of O6-methylguanine-DNA methyltransferase. The results suggest that MT participates as a cofactor or regulatory element in repair or tolerance of toxic alkylation lesions.

Overexpressed human metallothionein IIA gene protects Chinese hamster ovary cells from killing by alkylating agents.

Science.gov (United States)

Kaina, B; Lohrer, H; Karin, M; Herrlich, P

1990-01-01

Experiments were designed to detect survival advantages that cells gain by overexpressing metallothionein (MT). Chinese hamster ovary K1-2 cells and an x-ray-sensitive derivative were transfected with a bovine papillomavirus (BPV)-linked construct carrying the human metallothionein IIA (hMT-IIA) gene. Transfectants survived 40-fold higher levels of cadmium chloride, harbored at least 30 copies of hMT-IIA, and contained 25- to 166-fold more MT than the parent cells. Even under conditions of reduced glutathione synthesis, the transfectants were not more resistant to the lethal effects of ionizing radiation and bleomycin than the parent cells. Thus free radicals generated by these agents cannot be scavenged efficiently by MT in vivo. The hMT-IIA transfectants, however, but not control transfectants harboring a BPV-MT promoter-neo construct, tolerated significantly higher doses of the alkylating agents N-methyl-N-nitrosourea and N-methyl-N'-nitro-N-nitrosoguanidine. Resistance and MT overexpression occurred irrespective of selection and cultivation in cadmium and zinc. There was no increase in resistance to methyl methanesulfonate and N-hydroxyethyl-N-chloroethylnitrosourea. MT did not affect the degree of overall DNA methylation after N-methyl-N-nitrosourea treatment nor the level of O6-methylguanine-DNA methyltransferase. The results suggest that MT participates as a cofactor or regulatory element in repair or tolerance of toxic alkylation lesions. Images PMID:2320583

Magnetic resonance imaging contrast agents: Overview and perspectives

International Nuclear Information System (INIS)

Yan Guoping; Robinson, Leslie; Hogg, Peter

2007-01-01

Magnetic resonance imaging (MRI) is a non-invasive clinical imaging modality, which has become widely used in the diagnosis and/or staging of human diseases around the world. Some MRI examinations include the use of contrast agents. The categorizations of currently available contrast agents have been described according to their effect on the image, magnetic behavior and biodistribution in the body, respectively. In this field, superparamagnetic iron oxide particles and soluble paramagnetic metal chelates are two main classes of contrast agents for MRI. This review outlines the research and development of MRI contrast agents. In future, the ideal MRI contrast agent will be focused on the neutral tissue- or organ-targeting materials with high relaxivity and specificity, low toxicity and side effects, suitable long intravascular duration and excretion time, high contrast enhancement with low dose in vivo, and with minimal cost

Mind-Reading and Behavior-Reading against Agents with and without Anthropomorphic Features in a Competitive Situation.

Science.gov (United States)

Terada, Kazunori; Yamada, Seiji

2017-01-01

Humans use two distinct cognitive strategies separately to understand and predict other humans' behavior. One is mind-reading, in which an internal state such as an intention or an emotional state is assumed to be a source of a variety of behaviors. The other is behavior-reading, in which an actor's behavior is modeled based on stimulus-response associations without assuming internal states behind the behavior. We hypothesize that anthropomorphic features are key for an observer switching between these two cognitive strategies in a competitive situation. We provide support for this hypothesis through two studies using four agents with different appearances. We show that only a human agent was thought to possess both the ability to generate a variety of behaviors and internal mental states, such as minds and emotions (Study 1). We also show that humans used mixed (opposing) strategies against a human agent and exploitative strategies against the agents with mechanical appearances when they played a repeated zero-sum game (Study 2). Our findings show that humans understand that human behavior is varied; that humans have internal states, such as minds and emotions; that the behavior of machines is governed by a limited number of fixed rules; and that machines do not possess internal mental states. Our findings also suggest that the function of mind-reading is to trigger a strategy for use against agents with variable behavior and that humans exploit others who lack behavioral variability based on behavior-reading in a competitive situation.

Effect of Erythropoiesis-Stimulating Agent Policy Decisions

Data.gov (United States)

U.S. Department of Health & Human Services — Erythropoiesis-stimulating agents (ESAs) are used as a treatment for anemia in myelodysplastic syndromes (MDS) patients. In early 2007, the U.S. Food and Drug...

The self-aware diabetic patient software agent model.

Science.gov (United States)

Wang, Zhanle; Paranjape, Raman

2013-11-01

This work presents a self-aware diabetic patient software agent for representing a human diabetic patient. To develop a 24h, stochastic and self-aware patient agent, we extend the original seminal work of Ackerman et al. [1] in creating a mathematical model of human blood glucose levels in three aspects. (1) We incorporate the stochastic and unpredictable effects of daily living. (2) The Ackerman model is extended into the period of night-time. (3) Patients' awareness of their own conditions is incorporated. Simulation results are quantitatively assessed to demonstrate the effectiveness of lifestyle management, such as adjusting the amount of food consumed, meal schedule, intensity of exercise and level of medication. In this work we show through the simulation that the average blood glucose can be reduced by as much as 51% due to careful lifestyle management. Self monitoring blood glucose is also quantitatively evaluated. The simulation results show that the average blood glucose is further dropped by 25% with the assistance of blood glucose samples. In addition, the blood glucose is perfectly controlled in the target range during the simulation period as a result of joint efforts of lifestyle management and self monitoring blood glucose. This study focuses on demonstrating how human patients' behavior, specifically lifestyle and self monitoring of blood glucose, affects blood glucose controls on a daily basis. This work does not focus on the insulin-glucose interaction of an individual human patient. Our conclusion is that this self-aware patient agent model is capable of adequately representing diabetic patients and of evaluating their dynamic behaviors. It can also be incorporated into a multi-agent system by introducing other healthcare components so that more interesting insights such as the healthcare quality, cost and performance can be observed. © 2013 Published by Elsevier Ltd.

Embodied Conversational Agents in Clinical Psychology : A Scoping Review

NARCIS (Netherlands)

Provoost, Simon; Lau, Ho Ming; Ruwaard, Jeroen; Riper, Heleen

2017-01-01

BACKGROUND: Embodied conversational agents (ECAs) are computer-generated characters that simulate key properties of human face-to-face conversation, such as verbal and nonverbal behavior. In Internet-based eHealth interventions, ECAs may be used for the delivery of automated human support factors.

Helminth parasites of cats from the Vientiane Province, Laos, as indicators of the occurrence of causative agents of human parasitoses

Directory of Open Access Journals (Sweden)

Scholz T.

2003-12-01

Full Text Available A total of 55 domestic cats (Felis calus f. domestico and one wild (Bengal cat (Prionailurus bengalensis from the Vientiane Province, central Laos, were examined for helminth parasites with emphasis given to potential human parasites. The following species were found (parasites infective to man marked with an asterisk: Opisthorchis viverrini*, Haplorchis pumilio*,H. laichui*,H. yokogawai*, Stellantchasmus falcatus* (Digenea; Spirometra sp.*, Dipylidium caninum*, Taenia taeniaeformis (Cestoda; Capillariidae gen. sp., Toxocara canis*, T. cati*, Ancylostoma ceylanicum*, A. tubaeforme, Gnathostoma spinigerum*, Physaloptera preputials (Nematoda; and Oncicola sp. (Acanthocephala. This study demonstrated that examination of cats may provide useful data on the occurrence of helminths which are potential causative agents of human diseases.

A Principal-Agent Analysis of the Family: Implications for the Welfare State

OpenAIRE

Munro, Lauchlan

1999-01-01

The principal-agent literature has focussed on situations where both principal and agent are assumed to be capable of defining and defending their own interests. The principal-agent literature has thus ignored an important set of cases where the principal is incapable of acting on her own behalf, and so is assigned an agent by law or custom. Such cases account for around 40% of humanity and for a similarly substantial proportion of all principal-agent interactions. This paper applies principa...

Anti-Inflammatory Agent Indomethacin Reduces Invasion and Alters Metabolism in a Human Breast Cancer Cell Line

Directory of Open Access Journals (Sweden)

Ellen Ackerstaff

2007-03-01

Full Text Available Hostile physiological environments such as hypoxia and acidic extracellular pH, which exist in solid tumors, may promote invasion and metastasis through inflammatory responses and formation of eicosanoids. Here, we have investigated the effects of the antiinflammatory agent indomethacin on the invasion and metabolism of the human breast cancer cell line MDAMB-435 in Dulbecco's Modified Eagles (DME-based or Roswell Park Memorial Institute (RPMI-based cell medium, using a magnetic resonance-compatible invasion assay. Indomethacin treatment significantly reduced the invasion of MDA-MB-435 cells independent of the culture and perfusion conditions examined. Significant changes were detected in levels of intracellular choline phospholipid metabolites and in triglyceride (TG concentrations of these cells, depending on indomethacin treatment and basal cell medium used. Additionally, genetic profiling of breast cancer cells, grown and treated with low-dose indomethacin in cell culture using an RPMI-based medium, revealed the upregulation of several genes implicating cyclooxygenaseindependent targets of indomethacin. These data confirm the ability of an anti-inflammatory agent to reduce breast cancer invasion and demonstrate, depending on cell culture and perfusion conditions, that the indomethacin-induced decrease in invasion is associated with changes in choline phospholipid metabolism, TG metabolism, and gene expression.

Using the Agent-Based Modeling in Economic Field

Directory of Open Access Journals (Sweden)

Nora Mihail

2006-10-01

For ABM, a complex system is a system of individual agents who have the freedom to act in ways that are not always totally predictable, and whose actions are interconnected such that one agent’s actions changes the context (environment for other agents. These are many examples of such complex systems: the stock market, the human body immune system, a business organization, an institution, a work-team, a family etc.

Hypoxia-mimetic agents inhibit proliferation and alter the morphology of human umbilical cord-derived mesenchymal stem cells

Directory of Open Access Journals (Sweden)

Zeng Hui-Lan

2011-08-01

Full Text Available Abstract Background The therapeutic efficacy of human mesenchymal stem cells (hMSCs for the treatment of hypoxic-ischemic diseases is closely related to level of hypoxia in the damaged tissues. To elucidate the potential therapeutic applications and limitations of hMSCs derived from human umbilical cords, the effects of hypoxia on the morphology and proliferation of hMSCs were analyzed. Results After treatment with DFO and CoCl2, hMSCs were elongated, and adjacent cells were no longer in close contact. In addition, vacuole-like structures were observed within the cytoplasm; the rough endoplasmic reticulum expanded, and expanded ridges were observed in mitochondria. In addition, DFO and CoCl2 treatments for 48 h significantly inhibited hMSCs proliferation in a concentration-dependent manner (P Conclusions The hypoxia-mimetic agents, DFO and CoCl2, alter umbilical cord-derived hMSCs morphology and inhibit their proliferation through influencing the cell cycle.

Research on operation and maintenance support system adaptive to human recognition and understanding in human-centered plant

International Nuclear Information System (INIS)

Numano, Masayoshi; Matsuoka, Takeshi; Mitomo, N.

2004-01-01

As a human-centered plant, advanced nuclear power plant needs appropriate role sharing between human and mobile intelligent agents. Human-machine cooperation for plant operation and maintenance activities is also required with an advanced interface. Plant's maintenance is programmed using mobile robots working under the radiation environments instead of human beings. Operation and maintenance support system adaptive to human recognition and understanding should be developed to establish adequate human and machine interface so as to induce human capabilities to the full and enable human to take responsibility for plan's operation. Plant's operation and maintenance can be cooperative activities between human and intelligent automonous agents having surveillance and control functions. Infrastructure of multi-agent simulation system for the support system has been investigated and developed based on work plans derived from the scheduler. (T. Tanaka)

From automata to animate beings: the scope and limits of attributing socialness to artificial agents.

Science.gov (United States)

Hortensius, Ruud; Cross, Emily S

2018-05-11

Understanding the mechanisms and consequences of attributing socialness to artificial agents has important implications for how we can use technology to lead more productive and fulfilling lives. Here, we integrate recent findings on the factors that shape behavioral and brain mechanisms that support social interactions between humans and artificial agents. We review how visual features of an agent, as well as knowledge factors within the human observer, shape attributions across dimensions of socialness. We explore how anthropomorphism and dehumanization further influence how we perceive and interact with artificial agents. Based on these findings, we argue that the cognitive reconstruction within the human observer is likely to be far more crucial in shaping our interactions with artificial agents than previously thought, while the artificial agent's visual features are possibly of lesser importance. We combine these findings to provide an integrative theoretical account based on the "like me" hypothesis, and discuss the key role played by the Theory-of-Mind network, especially the temporal parietal junction, in the shift from mechanistic to social attributions. We conclude by highlighting outstanding questions on the impact of long-term interactions with artificial agents on the behavioral and brain mechanisms of attributing socialness to these agents. © 2018 New York Academy of Sciences.

Evaluating the effect of human activity patterns on air pollution exposure using an integrated field-based and agent-based modelling framework

Science.gov (United States)

Schmitz, Oliver; Beelen, Rob M. J.; de Bakker, Merijn P.; Karssenberg, Derek

2015-04-01

Constructing spatio-temporal numerical models to support risk assessment, such as assessing the exposure of humans to air pollution, often requires the integration of field-based and agent-based modelling approaches. Continuous environmental variables such as air pollution are best represented using the field-based approach which considers phenomena as continuous fields having attribute values at all locations. When calculating human exposure to such pollutants it is, however, preferable to consider the population as a set of individuals each with a particular activity pattern. This would allow to account for the spatio-temporal variation in a pollutant along the space-time paths travelled by individuals, determined, for example, by home and work locations, road network, and travel times. Modelling this activity pattern requires an agent-based or individual based modelling approach. In general, field- and agent-based models are constructed with the help of separate software tools, while both approaches should play together in an interacting way and preferably should be combined into one modelling framework, which would allow for efficient and effective implementation of models by domain specialists. To overcome this lack in integrated modelling frameworks, we aim at the development of concepts and software for an integrated field-based and agent-based modelling framework. Concepts merging field- and agent-based modelling were implemented by extending PCRaster (http://www.pcraster.eu), a field-based modelling library implemented in C++, with components for 1) representation of discrete, mobile, agents, 2) spatial networks and algorithms by integrating the NetworkX library (http://networkx.github.io), allowing therefore to calculate e.g. shortest routes or total transport costs between locations, and 3) functions for field-network interactions, allowing to assign field-based attribute values to networks (i.e. as edge weights), such as aggregated or averaged

An agent-based hydroeconomic model to evaluate water policies in Jordan

Science.gov (United States)

Yoon, J.; Gorelick, S.

2014-12-01

Modern water systems can be characterized by a complex network of institutional and private actors that represent competing sectors and interests. Identifying solutions to enhance water security in such systems calls for analysis that can adequately account for this level of complexity and interaction. Our work focuses on the development of a hierarchical, multi-agent, hydroeconomic model that attempts to realistically represent complex interactions between hydrologic and multi-faceted human systems. The model is applied to Jordan, one of the most water-poor countries in the world. In recent years, the water crisis in Jordan has escalated due to an ongoing drought and influx of refugees from regional conflicts. We adopt a modular approach in which biophysical modules simulate natural and engineering phenomena, and human modules represent behavior at multiple scales of decision making. The human modules employ agent-based modeling, in which agents act as autonomous decision makers at the transboundary, state, organizational, and user levels. A systematic nomenclature and conceptual framework is used to characterize model agents and modules. Concepts from the Unified Modeling Language (UML) are adopted to promote clear conceptualization of model classes and process sequencing, establishing a foundation for full deployment of the integrated model in a scalable object-oriented programming environment. Although the framework is applied to the Jordanian water context, it is generalizable to other regional human-natural freshwater supply systems.

21 CFR 316.22 - Permanent-resident agent for foreign sponsor.

Science.gov (United States)

2010-04-01

... SERVICES (CONTINUED) DRUGS FOR HUMAN USE ORPHAN DRUGS Designation of an Orphan Drug § 316.22 Permanent-resident agent for foreign sponsor. Every foreign sponsor that seeks orphan-drug designation shall name a permanent resident of the United States as the sponsor's agent upon whom service of all processes, notices...

Biodegradable human serum albumin nanoparticles as contrast agents for the detection of hepatocellular carcinoma by magnetic resonance imaging.

Science.gov (United States)

Watcharin, Waralee; Schmithals, Christian; Pleli, Thomas; Köberle, Verena; Korkusuz, Hüdayi; Huebner, Frank; Zeuzem, Stefan; Korf, Hans W; Vogl, Thomas J; Rittmeyer, Claudia; Terfort, Andreas; Piiper, Albrecht; Gelperina, Svetlana; Kreuter, Jörg

2014-05-01

Tumor visualization by magnetic resonance imaging (MRI) and nanoparticle-based contrast agents may improve the imaging of solid tumors such as hepatocellular carcinoma (HCC). In particular, human serum albumin (HSA) nanoparticles appear to be a suitable carrier due to their safety and feasibility of functionalization. In the present study HSA nanoparticles were conjugated with gadolinium diethylenetriaminepentaacetic acid (Gd-DTPA) using carbodiimide chemistry. The nanoparticles had a uniform spherical shape and a diameter of 235±19nm. For better optical visualization in vitro and in vivo, the HSA-Gd nanoparticles were additionally labeled with rhodamine 123. As shown by confocal microscopy and flow cytometry analysis, the fluorescent nanoparticles were readily taken up by Huh-7 hepatocellular carcinoma cells. After 24h incubation in blood serum, less than 5% of the Gd(III) was released from the particles, which suggests that this nanoparticulate system may be stable in vivo and, therefore, may serve as potentially safe T1 MRI contrast agent for MRI of hepatocellular carcinoma. Copyright © 2013 Elsevier B.V. All rights reserved.

Social Robots as Persuasive Agents

DEFF Research Database (Denmark)

Vlachos, Evgenios; Schärfe, Henrik

2014-01-01

Robots are more and more used in a social context, and in this paper we try to formulate a research agenda concerning ethical issues around social HRI in order to be prepared for future scenarios where robots may be a naturally integrated part of human society. We outline different paradigms to d...... to describe the role of social robots in communication processes with humans, and connect HRI with the topic of persuasive technology in health care, to critically reflect the potential benefits of using social robots as persuasive agents....

Measurement and Evaluation of Animated Pedagogical Agents and Their Use in Training

National Research Council Canada - National Science Library

Hosie, Thomas

2004-01-01

... on-screen agents that speak in a human voice rather than a machine-synthesized voice; (b) an image effect, an agent's image fosters learning when it is programmed to explain complex visual information aurally; (c...

Semiotics, Multi-Agent Systems and Organizations

NARCIS (Netherlands)

Gazendam, H.W.M.; Jorna, René J.

1998-01-01

Multi-agent systems are promising as models of organization because they are based on the idea that most work in human organizations is done based on intelligence, communication, cooperation, and massive parallel processing. They offer an alternative for system theories of organization, which are

FeGA: A feedback-generating agent

NARCIS (Netherlands)

Heuvelink, A.; Mioch, T.

2008-01-01

In current simulation-based training of knowledgeintensive tasks, human instructors are needed to evaluate a student's task performance. This paper reports a study into the development of a multi-agent-based training system that evaluates student behavior at the result-level (quality of performance)

Human factor reliability program

International Nuclear Information System (INIS)

Knoblochova, L.

2017-01-01

The human factor's reliability program was at Slovenske elektrarne, a.s. (SE) nuclear power plants. introduced as one of the components Initiatives of Excellent Performance in 2011. The initiative's goal was to increase the reliability of both people and facilities, in response to 3 major areas of improvement - Need for improvement of the results, Troubleshooting support, Supporting the achievement of the company's goals. The human agent's reliability program is in practice included: - Tools to prevent human error; - Managerial observation and coaching; - Human factor analysis; -Quick information about the event with a human agent; -Human reliability timeline and performance indicators; - Basic, periodic and extraordinary training in human factor reliability(authors)

Effects of a Pedagogical Agent's Emotional Expressiveness on Learner Perceptions

Science.gov (United States)

Romero, Enilda J.; Watson, Ginger S.

2012-01-01

The use of animated pedagogical agents or avatars in instruction has lagged behind their use in entertainment. This is due in part to the cost and complexity of development and implementation of agents in educational settings, but also results from a lack of research to understand how emotions from animated agents influence instructional effectiveness. The phenomenological study presented here assesses the perceptions of eight learners interacting with low and high intensity emotionally expressive pedagogical agents in a computer-mediated environment. Research methods include maximum variation and snowball sampling with random assignment to treatment. The resulting themes incorporate perceptions of importance, agent humanness, enjoyment, implementation barriers, and suggested improvements. Design recommendations and implications for future research are presented.

Mind-Reading and Behavior-Reading against Agents with and without Anthropomorphic Features in a Competitive Situation

Directory of Open Access Journals (Sweden)

Kazunori Terada

2017-07-01

Full Text Available Humans use two distinct cognitive strategies separately to understand and predict other humans' behavior. One is mind-reading, in which an internal state such as an intention or an emotional state is assumed to be a source of a variety of behaviors. The other is behavior-reading, in which an actor's behavior is modeled based on stimulus-response associations without assuming internal states behind the behavior. We hypothesize that anthropomorphic features are key for an observer switching between these two cognitive strategies in a competitive situation. We provide support for this hypothesis through two studies using four agents with different appearances. We show that only a human agent was thought to possess both the ability to generate a variety of behaviors and internal mental states, such as minds and emotions (Study 1. We also show that humans used mixed (opposing strategies against a human agent and exploitative strategies against the agents with mechanical appearances when they played a repeated zero-sum game (Study 2. Our findings show that humans understand that human behavior is varied; that humans have internal states, such as minds and emotions; that the behavior of machines is governed by a limited number of fixed rules; and that machines do not possess internal mental states. Our findings also suggest that the function of mind-reading is to trigger a strategy for use against agents with variable behavior and that humans exploit others who lack behavioral variability based on behavior-reading in a competitive situation.

Complex responses to alkylating agents

International Nuclear Information System (INIS)

Samson, L.D.

2003-01-01

Using Affymetrix oligonucleotide GeneChip analysis, we previously found that, upon exposure to the simple alkylating agent methylmethane sulfonate, the transcript levels for about one third of the Saccharomyces cerevisiae genome (∼2,000 transcripts) are induced or repressed during the first hour or two after exposure. In order to determine whether the responsiveness of these genes has any relevance to the protection of cells against alkylating agents we have undertaken several follow-up studies. First, we explored the specificity of this global transcriptional response to MMS by measuring the global response of S. cerevisiae to a broad range of agents that are known to induce DNA damage. We found that each agent produced a very different mRNA transcript profile, even though the exposure doses produced similar levels of toxicity. We also found that the selection of genes that respond to MMS is highly dependent upon what cell cycle phase the cells are in at the time of exposure. Computational clustering analysis of the dataset derived from a large number of exposures identified several promoter motifs that are likely to control some of the regulons that comprise this large set of genes that are responsive to DNA damaging agents. However, it should be noted that these agents damage cellular components other than DNA, and that the responsiveness of each gene need not be in response to DNA damage per se. We have also begun to study the response of other organisms to alkylating agents, and these include E. coli, cultured mouse and human cells, and mice. Finally, we have developed a high throughput phenotypic screening method to interrogate the role of all non-essential S. cerevisiae genes (about 4,800) in protecting S. cerevisiae against the deleterious effects of alkylating agents; we have termed this analysis 'genomic phenotyping'. This study has uncovered a plethora of new pathways that play a role in the recovery of eukaryotic cells after exposure to toxic

Identifying Requirements for Effective Human-Automation Teamwork

Energy Technology Data Exchange (ETDEWEB)

Jeffrey C. Joe; John O' Hara; Heather D. Medema; Johanna H. Oxstrand

2014-06-01

Previous studies have shown that poorly designed human-automation collaboration, such as poorly designed communication protocols, often leads to problems for the human operators, such as: lack of vigilance, complacency, and loss of skills. These problems often lead to suboptimal system performance. To address this situation, a considerable amount of research has been conducted to improve human-automation collaboration and to make automation function better as a “team player.” Much of this research is based on an understanding of what it means to be a good team player from the perspective of a human team. However, the research is often based on a simplified view of human teams and teamwork. In this study, we sought to better understand the capabilities and limitations of automation from the standpoint of human teams. We first examined human teams to identify the principles for effective teamwork. We next reviewed the research on integrating automation agents and human agents into mixed agent teams to identify the limitations of automation agents to conform to teamwork principles. This research resulted in insights that can lead to more effective human-automation collaboration by enabling a more realistic set of requirements to be developed based on the strengths and limitations of all agents.

Issues in multimodal nonverbal communication and emotion in embodied (conversational) agents

NARCIS (Netherlands)

Nijholt, Antinus; Callaos, N.; Breda, A.; Fernandez, A.

2002-01-01

Virtual worlds are getting inhabited by virtual humans. Sometimes they act as (autonomous) embodied conversational agents; sometimes they represent human visitors and reflect (real-time) actions performed by the human visitors or users of the environment. It is not always necessary to represent a

Penetratin and derivatives acting as antifungal agents

NARCIS (Netherlands)

Masman, Marcelo F.; Rodriguez, Ana M.; Raimondi, Marcela; Zacchino, Susana A.; Luiten, Paul G. M.; Somlai, Csaba; Kortvelyesi, Tamas; Penke, Botond; Enriz, Ricardo D.

The synthesis, in vitro evaluation, and conformational study of RQIKTWFQNRRMKWKK-NH(2) (penetratin) and related derivatives acting as antifungal agents are reported. Penetratin and some of its derivatives displayed antifungal activity against the human opportunistic pathogenic standardized ATCC

Behavioral effects of nerve agents: laboratory animal models

International Nuclear Information System (INIS)

Myers, T. M.

2009-01-01

Diverse and often subtle behavioral consequences have been reported for humans exposed to nerve agents. Laboratory studies of nerve agent exposure offer rigorous control over important variables, but species other than man must be used. Nonhuman primate models offer the best means of identifying the toxic nervous system effects of nerve agent insult and the countermeasures best capable of preventing or attenuating these effects. Comprehensive behavioral models must evaluate preservation and recovery of function as well as new learning ability. The throughput and sensitivity of the tests chosen are important considerations. A few nonhuman primate studies will be discussed to elaborate recent successes, current limitations, and future directions.(author)

Human exposure to airborne fungi from genera used as biocontrol agents in plant production.

Science.gov (United States)

Madsen, Anne Mette; Hansen, Vinni Mona; Meyling, Nicolai Vitt; Eilenberg, Jørgen

2007-01-01

The fungi Trichoderma harzianum, T. polysporum, T. viride, Paeciliomyces fumosoroseus, P. lilacinus, Verticillium/lecanicillium lecanii, Ulocladium oudemansii, U. atrum and Beauveria bassiana are used or considered to be used for biocontrol of pests and plant diseases. Human exposure to these fungi in environments where they may naturally occur or are used as biocontrol agents has not been directly investigated to date. This review aims to provide an overview of the current knowledge of human exposure to fungi from the relevant genera. The subject of fungal taxonomy due to the rapid development of this issue is also discussed. B. bassiana, V. lecanii, T. harzianum, T. polysporum, P. lilacinus and U. oudemansii were infrequently present in the air and thus people in general seem to be seldom exposed to these fungi. However, when V. lecanii was present, high concentrations were measured. Fungi from the genera Trichoderma, Paecilomyces and Ulocladium were rarely identified to the species level and sometimes high concentrations were reported. T. viride and U. atrum were detected frequently in different environments and sometimes with a high frequency of presence in samples. Thus, people seem to be frequently exposed to these fungi. Sequence data have led to recent revisions of fungal taxonomy, and in future studies it is important to specify the taxonomy used for identification, thus making comparisons possible.

Issues Related to Experience & Automated Agent Technology in Synthetic Task Performance

National Research Council Canada - National Science Library

Coovert, Michael D; Riddle, Dawn L; Gordon, Thomas; Miles, Donald; Hoffman, Kimberly; King, Thomas; Elliott, Linda; Dalrymple, Mathieu; Schiflett, Samual; Chaiken, Scott

2001-01-01

.... Elliott, Stoyen and Chaiken (2000) note the limits of human cognitive processing relative to this demand and suggest agent technology has the potential to offer effective information and decision support the human operator...

Frequency of resistance to methicillin and other antimicrobial agents among Staphylococcus aureus strains isolated from pigs and their human handlers in Trinidad

Directory of Open Access Journals (Sweden)

Annika Gordon

2014-04-01

Full Text Available Background: Methicillin-resistant Staphylococcus aureus (MRSA has emerged recently worldwide in production animals, particularly pigs and veal calves, which act as reservoirs for MRSA strains for human infection. The study determined the prevalence of MRSA and other resistant strains of S. aureus isolated from the anterior nares of pigs and human handlers on pig farms in Trinidad. Methods: Isolation of S. aureus was done by concurrently inoculating Baird-Parker agar (BPA and Chromagar MRSA (CHROM with swab samples and isolates were identified using standard methods. Suspect MRSA isolates from Chromagar and BPA were subjected to confirmatory test using Oxoid PBP2 latex agglutination test. The disc diffusion method was used to determine resistance to antimicrobial agents. Results: The frequency of isolation of MRSA was 2.1% (15 of 723 for pigs but 0.0% (0 of 72 for humans. Generally, for isolates of S. aureus from humans there was a high frequency of resistance compared with those from pigs, which had moderate resistance to the following antimicrobials: penicillin G (54.5%, 51.5%, ampicillin (59.1%, 49.5%, and streptomycin (59.1%, 37.1%, respectively. There was moderate resistance to tetracycline (36.4%, 41.2% and gentamycin (27.2%, 23.7% for human and pig S. aureus isolates, respectively, and low resistance to sulfamethoxazole-trimethoprim (4.5%, 6.2% and norfloxacin (9.1%, 12.4%, respectively. The frequency of resistance to oxacillin by the disc method was 36.4 and 34.0% from S. aureus isolates from humans and pigs, respectively. Out of a total of 78 isolates of S. aureus from both human and pig sources that were resistant to oxacillin by the disc diffusion method, only 15 (19.2% were confirmed as MRSA by the PBP'2 latex test kit. Conclusions: The detection of MRSA strains in pigs, albeit at a low frequency, coupled with a high frequency of resistance to commonly used antimicrobial agents in pig and humans could have zoonotic and therapeutic

Agent Based Modelling for Social Simulation

NARCIS (Netherlands)

Smit, S.K.; Ubink, E.M.; Vecht, B. van der; Langley, D.J.

2013-01-01

This document is the result of an exploratory project looking into the status of, and opportunities for Agent Based Modelling (ABM) at TNO. The project focussed on ABM applications containing social interactions and human factors, which we termed ABM for social simulation (ABM4SS). During the course

Occupational exposure to biological agents intentionally used in Polish enterprises

Directory of Open Access Journals (Sweden)

Anna Kozajda

2015-02-01

Full Text Available Background: The paper presents the intentional use of biological agents for industrial, diagnostic and research purposes in Polish enterprises. Material and Methods: The National Register of Biological Agents (Krajowy Rejestr Czynników Biologicznych – KRCB is an online database that collects the data on the intentional use of biological agents at work in Poland. Results: As of December 2013 there were 533 notifications in KRCB, mainly for diagnostic (73%, research (20% and industrial purposes (7%. Mostly there were hospital diagnostic laboratories (37%, and other laboratories (35%, as well as higher education and research institutions (11%. In total, 4015 workers (91.7% of women, 8.3% of men were exposed to biological agents. Agents classified in risk group 2 were used in 518 enterprises, and in risk group 3 in 107 enterprises. Of those agents the following bacteria were the most frequently used: Escherichia coli except for non-pathogenic strains (455 enterprises and 3314 exposed workers; Staphylococcus aureus (445 and 3270; and Pseudomonas aeruginosa (406 and 2969, respectively. In 66 enterprises there were used biological agents recognized by the International Agency for Research on Cancer (IARC as carcinogens. They are viruses: Epstein-Barr (7 enterprises, 181 exposed workers; hepatitis B (16 and 257; hepatitis C virus (15 and 243; human immunodeficiency virus (8 and 107; human papillomaviruses (2 and 4; parasites: Clonorchis viverrini (1 and 2; Clonorchos sinensis (1 and 2; Schistosoma haematobium (1 and 2 and bacteria Helicobacter pylori (15 and 230, respectively. Conclusions: The National Register of Biological Agents at Work permits to evaluate the situation of occupational exposure to biological agents used intentionally in enterprises in Poland. Med Pr 2015;66(1:39–47

The effect of multiple modalities on the perception of a listening agent

NARCIS (Netherlands)

Poppe, Ronald Walter; ter Maat, Mark; Heylen, Dirk K.J.

Listening agents are IVAs that display attentive listening behavior to a human speaker. The research into listening agents has mainly focused on (1) automatically timing listener responses; and (2) investigating the perceptual quality of listening behavior. Both issues have predominantly been

Mycobacterium avium subspecies paratuberculosis: A possible causative agent in human morbidity and risk to public health safety

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Mary Garvey

2018-05-01

Full Text Available Mycobacterium avium subspecies paratuberculosis is a bacterial parasite and the causative agent of paratuberculosis, a disease predominately found in cattle and sheep. Infection with this microorganism results in substantial farming economic losses and animal morbidity. The link between infection with this pathogen and human disease has been theorised for many years with Crohn’s disease being one of many suspected resultant conditions. Mycobacterium avium may be spread from animal to human hosts by water and foodborne transmission routes, where the foodborne route of exposure represents a significant risk for susceptible populations, namely children and the immune-compromised. Following colonisation of the host, the parasitic organism evades the host immune system by use of molecular mimicry, displaying peptide sequences similar to that of the host cells causing a disruption of self-verses non self-recognition. Theoretically, this failure to recognise the invading organism as distinct from host cells may result in numerous autoimmune conditions. Here, the author presents current information assessing the link between numerous diseases states in humans such inflammatory bowel disease, Type 1 diabetes, rheumatoid arthritis, Hashimoto\\'s thyroiditis, multiple sclerosis and autism following infection with Mycobacterium avium paratuberculosis. The possibility of zoonotic transmission of the organism and its significant risk to public health safety as a consequence is also discussed.

Simultaneous Quantification of Antidiabetic Agents in Human Plasma by a UPLC-QToF-MS Method.

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Mariana Millan Fachi

Full Text Available An ultra-performance liquid chromatography quadrupole time-of-flight mass spectrometry method for the simultaneous quantification of chlorpropamide, glibenclamide, gliclazide, glimepiride, metformin, nateglinide, pioglitazone, rosiglitazone, and vildagliptin in human plasma was developed and validated, using isoniazid and sulfaquinoxaline as internal standards. Following plasma protein precipitation using acetonitrile with 1% formic acid, chromatographic separation was performed on a cyano column using gradient elution with water and acetonitrile, both containing 0.1% formic acid. Detection was performed in a quadrupole time-of-flight analyzer, using electrospray ionization operated in the positive mode. Data from validation studies demonstrated that the new method is highly sensitive, selective, precise (RSD 0.99, free of matrix and has no residual effects. The developed method was successfully applied to volunteers' plasma samples. Hence, this method was demonstrated to be appropriate for clinical monitoring of antidiabetic agents.

Mitochondrial targeting of human O6-methylguanine DNA methyltransferase protects against cell killing by chemotherapeutic alkylating agents.

Science.gov (United States)

Cai, Shanbao; Xu, Yi; Cooper, Ryan J; Ferkowicz, Michael J; Hartwell, Jennifer R; Pollok, Karen E; Kelley, Mark R

2005-04-15

DNA repair capacity of eukaryotic cells has been studied extensively in recent years. Mammalian cells have been engineered to overexpress recombinant nuclear DNA repair proteins from ectopic genes to assess the impact of increased DNA repair capacity on genome stability. This approach has been used in this study to specifically target O(6)-methylguanine DNA methyltransferase (MGMT) to the mitochondria and examine its impact on cell survival after exposure to DNA alkylating agents. Survival of human hematopoietic cell lines and primary hematopoietic CD34(+) committed progenitor cells was monitored because the baseline repair capacity for alkylation-induced DNA damage is typically low due to insufficient expression of MGMT. Increased DNA repair capacity was observed when K562 cells were transfected with nuclear-targeted MGMT (nucl-MGMT) or mitochondrial-targeted MGMT (mito-MGMT). Furthermore, overexpression of mito-MGMT provided greater resistance to cell killing by 1,3-bis (2-chloroethyl)-1-nitrosourea (BCNU) than overexpression of nucl-MGMT. Simultaneous overexpression of mito-MGMT and nucl-MGMT did not enhance the resistance provided by mito-MGMT alone. Overexpression of either mito-MGMT or nucl-MGMT also conferred a similar level of resistance to methyl methanesulfonate (MMS) and temozolomide (TMZ) but simultaneous overexpression in both cellular compartments was neither additive nor synergistic. When human CD34(+) cells were infected with oncoretroviral vectors that targeted O(6)-benzylguanine (6BG)-resistant MGMT (MGMT(P140K)) to the nucleus or the mitochondria, committed progenitors derived from infected cells were resistant to 6BG/BCNU or 6BG/TMZ. These studies indicate that mitochondrial or nuclear targeting of MGMT protects hematopoietic cells against cell killing by BCNU, TMZ, and MMS, which is consistent with the possibility that mitochondrial DNA damage and nuclear DNA damage contribute equally to alkylating agent-induced cell killing during chemotherapy.

Unibot, a Universal Agent Architecture for Robots

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Saša Mladenović

2017-01-01

Full Text Available Today there are numerous robots in different applications domains despite the fact that they still have limitations in perception, actuation and decision process. Consequently, robots usually have limited autonomy, they are domain specific or have difficulty to adapt on new environments. Learning is the property that makes an agent intelligent and the crucial property that a robot should have to proliferate into the human society. Embedding the learning ability into the robot may simplify the development of the robot control mechanism. The motivation for this research is to develop the agent architecture of the universal robot – Unibot. In our approach the agent is the robot i.e. Unibot that acts in the physical world and is capable of learning. The Unibot conducts several simultaneous simulations of a problem of interest like path-finding. The novelty in our approach is the Multi-Agent Decision Support System which is developed and integrated into the Unibot agent architecture in order to execute simultaneous simulations. Furthermore, the Unibot calculates and evaluates between multiple solutions, decides which action should be performed and performs the action. The prototype of the Unibot agent architecture is described and evaluated in the experiment supported by the Lego Mindstorms robot and the NetLogo.

FY1995 community support by mobile agents; 1995 nendo mobile agent ni yoru community keisei shien

Energy Technology Data Exchange (ETDEWEB)

NONE

1997-03-01

The purpose is to develop fundamental technologies for navigation systems and mobile computing systems in museums, theme parks and cities. Concretely, we implement software agents into the mobile computing environment which consists of PHS, mobile computers and mobile robots, and realize various functions to access regional information. We have studied on Communityware which supports human activities and communities by using mobile agents implemented into mobile computers and town robots. The mobile agents, which intelligently process information obtained in physical and virtual worlds, access regional information which is omnipresent in the environment. With respect to the approach using mobile computers, we have provided one hundred mobile computers in the international conference on multiagent systems 1996 and carried out the first experimentation of mobile computing in the world. The mobile computer has two functions: Community Viewer which displays interactions between members of communities and Social Matchmaker which supports to hold meetings by searching for people who have common interests. With respect to the approach using town robots, we have developed a robot system which can robustly behave in a complex outdoor environment by using vision agents embedded in the environment. The system aims at support of people in streets. (NEDO)

Stability of subsystem solutions in agent-based models

Science.gov (United States)

Perc, Matjaž

2018-01-01

The fact that relatively simple entities, such as particles or neurons, or even ants or bees or humans, give rise to fascinatingly complex behaviour when interacting in large numbers is the hallmark of complex systems science. Agent-based models are frequently employed for modelling and obtaining a predictive understanding of complex systems. Since the sheer number of equations that describe the behaviour of an entire agent-based model often makes it impossible to solve such models exactly, Monte Carlo simulation methods must be used for the analysis. However, unlike pairwise interactions among particles that typically govern solid-state physics systems, interactions among agents that describe systems in biology, sociology or the humanities often involve group interactions, and they also involve a larger number of possible states even for the most simplified description of reality. This begets the question: when can we be certain that an observed simulation outcome of an agent-based model is actually stable and valid in the large system-size limit? The latter is key for the correct determination of phase transitions between different stable solutions, and for the understanding of the underlying microscopic processes that led to these phase transitions. We show that a satisfactory answer can only be obtained by means of a complete stability analysis of subsystem solutions. A subsystem solution can be formed by any subset of all possible agent states. The winner between two subsystem solutions can be determined by the average moving direction of the invasion front that separates them, yet it is crucial that the competing subsystem solutions are characterised by a proper composition and spatiotemporal structure before the competition starts. We use the spatial public goods game with diverse tolerance as an example, but the approach has relevance for a wide variety of agent-based models.

Effects of inhibitors of DNA repair on the frequencies of chromosomal aberrations induced by x-rays or alkylating agents in cultured human lymphocytes

International Nuclear Information System (INIS)

Kihlman, B.A.; Andersson, H.C.

1986-01-01

In the first part of this presentation the authors give examples of the synergistic enhancements that are obtained with various inhibitor combinations in G/sub 2/. The second part of the presentation deals with the effects of two agents, also well known for their capacity to potentiate the frequency of chromosomal aberrations induced by physical and chemical agents, but with a different mechanism of action. These agents are caffeine and 3-aminobenzamide (3AB). Caffeine has for decades been used as an inhibitor of DNA repair although its mechanism of action has not been fully understood. 3AB has more recently come into focus as an efficient inhibitor of the synthesis of poly-(ADP-ribose), a substance believed to be of importance in connection with the repair of certain types of DNA damage. The results presented do not quite fit in with the general idea about the mode of action of these agents. All experiments were carried out with whole-blood cultures of human lymphocytes. When inhibitors were used as post-treatments, chromosomal aberrations were induced by X-rays or by the alkylating agents thiotepa (TT) and N-methyl-N'-nitro-N-nitrosoguanidine (MNNG). X-rays were generated by a Siemens Stabilipan 200 apparatus, at a dose rate of 0.5 Gy/min. The tube (TR 200f) was operated at 180 kV, 10 mA and the radiation filtered through 4 mm Al

A robust and rapid xenograft model to assess efficacy of chemotherapeutic agents for human acute myeloid leukemia

International Nuclear Information System (INIS)

Saland, E; Boutzen, H; Castellano, R; Pouyet, L; Griessinger, E; Larrue, C; Toni, F de; Scotland, S; David, M; Danet-Desnoyers, G; Vergez, F; Barreira, Y; Collette, Y; Récher, C; Sarry, J-E

2015-01-01

Relevant preclinical mouse models are crucial to screen new therapeutic agents for acute myeloid leukemia (AML). Current in vivo models based on the use of patient samples are not easy to establish and manipulate in the laboratory. Our objective was to develop robust xenograft models of human AML using well-characterized cell lines as a more accessible and faster alternative to those incorporating the use of patient-derived AML cells. Five widely used AML cell lines representing various AML subtypes were transplanted and expanded into highly immunodeficient non-obese diabetic/LtSz-severe combined immunodeficiency IL2Rγ c null mice (for example, cell line-derived xenografts). We show here that bone marrow sublethal conditioning with busulfan or irradiation has equal efficiency for the xenotransplantation of AML cell lines. Although higher number of injected AML cells did not change tumor engraftment in bone marrow and spleen, it significantly reduced the overall survival in mice for all tested AML cell lines. On the basis of AML cell characteristics, these models also exhibited a broad range of overall mouse survival, engraftment, tissue infiltration and aggressiveness. Thus, we have established a robust, rapid and straightforward in vivo model based on engraftment behavior of AML cell lines, all vital prerequisites for testing new therapeutic agents in preclinical studies

Effect of capping agents on the cytotoxicity of silver nanoparticles in human normal and cancer skin cell lines

Energy Technology Data Exchange (ETDEWEB)

Netchareonsirisuk, Ponsawan [Chulalongkorn University, Program in Biotechnology, Faculty of Science (Thailand); Puthong, Songchan [Chulalongkorn University, Antibody Production Research Unit, Institute of Biotechnology and Genetic Engineering (Thailand); Dubas, Stephan [Chulalongkorn University, Petroleum and Petrochemical College (Thailand); Palaga, Tanapat [Chulalongkorn University, Department of Microbiology, Faculty of Science (Thailand); Komolpis, Kittinan, E-mail: kittinan.k@chula.ac.th [Chulalongkorn University, Antibody Production Research Unit, Institute of Biotechnology and Genetic Engineering (Thailand)

2016-11-15

Silver nanoparticles (AgNPs) are among the most widely used nanomaterials in medical and consumer products. However, safety in the uses of AgNPs is still controversial. The toxicity of AgNPs toward various cell types has been reported to depend on the surface properties of the nanoparticles. In this study, the effect of AgNPs with the average size of 5–15 nm on the viability of the CCD-986SK human normal skin fibroblast cell line and A375 human malignant melanoma cell line was evaluated. Comparative toxicity studies, based on MTT assay, were performed by using either sodium alginate or poly (4-styrenesulfonic acid-co-maleic acid) sodium salt (PSSMA) as capping agent in the nanoparticle preparation. The cytotoxicity tests revealed that AgNO{sub 3} alone was highly toxic to both cell types while both alginate and PSSMA alone were not toxic. AgNPs capped with alginate were selectively toxic to the cancer cell line but not to the normal cell line while AgNPs capped with PSSMA were toxic to both cancer and normal cell lines. Judging from the 50 % inhibition concentration (IC{sub 50}), it was found that the cancer cell line was more sensitive to AgNPs than the normal cell line. Study on the mode of cell death by annexin V and propidium iodide staining revealed that AgNPs induced more apoptotic cell death (84–90 %) than necrosis (8–12 %) in the skin cancer cell line. These results suggest that the toxicity of AgNPs depended on the type of capping agent and the type of cell line.

Cognitive Model of Trust Dynamics Predicts Human Behavior within and between Two Games of Strategic Interaction with Computerized Confederate Agents.

Science.gov (United States)

Collins, Michael G; Juvina, Ion; Gluck, Kevin A

2016-01-01

When playing games of strategic interaction, such as iterated Prisoner's Dilemma and iterated Chicken Game, people exhibit specific within-game learning (e.g., learning a game's optimal outcome) as well as transfer of learning between games (e.g., a game's optimal outcome occurring at a higher proportion when played after another game). The reciprocal trust players develop during the first game is thought to mediate transfer of learning effects. Recently, a computational cognitive model using a novel trust mechanism has been shown to account for human behavior in both games, including the transfer between games. We present the results of a study in which we evaluate the model's a priori predictions of human learning and transfer in 16 different conditions. The model's predictive validity is compared against five model variants that lacked a trust mechanism. The results suggest that a trust mechanism is necessary to explain human behavior across multiple conditions, even when a human plays against a non-human agent. The addition of a trust mechanism to the other learning mechanisms within the cognitive architecture, such as sequence learning, instance-based learning, and utility learning, leads to better prediction of the empirical data. It is argued that computational cognitive modeling is a useful tool for studying trust development, calibration, and repair.

Robots As Intentional Agents: Using Neuroscientific Methods to Make Robots Appear More Social.

Science.gov (United States)

Wiese, Eva; Metta, Giorgio; Wykowska, Agnieszka

2017-01-01

Robots are increasingly envisaged as our future cohabitants. However, while considerable progress has been made in recent years in terms of their technological realization, the ability of robots to interact with humans in an intuitive and social way is still quite limited. An important challenge for social robotics is to determine how to design robots that can perceive the user's needs, feelings, and intentions, and adapt to users over a broad range of cognitive abilities. It is conceivable that if robots were able to adequately demonstrate these skills, humans would eventually accept them as social companions. We argue that the best way to achieve this is using a systematic experimental approach based on behavioral and physiological neuroscience methods such as motion/eye-tracking, electroencephalography, or functional near-infrared spectroscopy embedded in interactive human-robot paradigms. This approach requires understanding how humans interact with each other, how they perform tasks together and how they develop feelings of social connection over time, and using these insights to formulate design principles that make social robots attuned to the workings of the human brain. In this review, we put forward the argument that the likelihood of artificial agents being perceived as social companions can be increased by designing them in a way that they are perceived as intentional agents that activate areas in the human brain involved in social-cognitive processing. We first review literature related to social-cognitive processes and mechanisms involved in human-human interactions, and highlight the importance of perceiving others as intentional agents to activate these social brain areas. We then discuss how attribution of intentionality can positively affect human-robot interaction by (a) fostering feelings of social connection, empathy and prosociality, and by (b) enhancing performance on joint human-robot tasks. Lastly, we describe circumstances under which

Absence of specificity in inhibition of DNA repair replication by DNA-binding agents, cocarcinogens, and steroids in human cells

International Nuclear Information System (INIS)

Cleaver, J.E.; Painter, R.B.

1975-01-01

Although many chemicals, including cocarcinogens, DNA-binding agents, and steroids, inhibit repair replication of ultraviolet-induced damage to DNA in human lymphocytes and proliferating cells in culture, none of these chemicals is specific. Our results show that all the chemicals we tested inhibit normal DNA synthesis as much as or more than they inhibit repair replication. There is thus no evidence in our results to support the hypothesis that cocarcinogens are specific inhibitors of DNA repair or that any of the chemicals studied might be useful adjuncts to tumor therapy merely because of specific inhibition of radiation repair mechanisms

Characterization of the response of a human breast carcinoma cell line (T-47D) to radiation and chemotherapeutic agents

International Nuclear Information System (INIS)

Prager, A.; Ben-Hur, E.; Riklis, E.

1981-01-01

The response of a human breast carcinoma cell line (T-47D) to various antitumour agents, gamma irradiation, UV light and heat was studied, using the colony-forming ability technique. Combinations of radiation with drugs and heat were also tested. The resulting survival curves corresponded to one of five patterns: simple exponential, biphasic exponential, threshold exponential, exponential plateau and ineffectual. Whereas the cells were particularly sensitive to gamma irradiation, the response to UV light was normal. The patient from whom this cell line originated did not respond to METHOTREXATEsup(R) therapy. The in vitro results correlated with this observation. (author)

Constitutionality of enforcement of claims by private enforcement agents

Directory of Open Access Journals (Sweden)

Bodiroga Nikola

2014-01-01

Full Text Available The main focus of this paper is legal status of private enforcement agents in Serbia. The 2011 Serbian Law on Enforcement and Security has introduced private enforcement agents as legal professionals in charge mainly for carrying out of the enforcement. Special enforcement procedure for collection of utilities and similar claims has become exclusive competence of private enforcement agents. Since enforcement procedure has always been regarded as a set of coercive measures against enforcement debtor, it became questionable whether this coercion could be exercised by private enforcement agents. It has been argued by legal scholars that enforcement of civil judgments and other enforcement deeds belongs only to the state authority. The author tackles this issue from the standpoint of decisions of constitutional courts and jurisprudence of European Court of Human Rights.

The next generation of interoperability agents in healthcare.

Science.gov (United States)

Cardoso, Luciana; Marins, Fernando; Portela, Filipe; Santos, Manuel; Abelha, António; Machado, José

2014-05-16

Interoperability in health information systems is increasingly a requirement rather than an option. Standards and technologies, such as multi-agent systems, have proven to be powerful tools in interoperability issues. In the last few years, the authors have worked on developing the Agency for Integration, Diffusion and Archive of Medical Information (AIDA), which is an intelligent, agent-based platform to ensure interoperability in healthcare units. It is increasingly important to ensure the high availability and reliability of systems. The functions provided by the systems that treat interoperability cannot fail. This paper shows the importance of monitoring and controlling intelligent agents as a tool to anticipate problems in health information systems. The interaction between humans and agents through an interface that allows the user to create new agents easily and to monitor their activities in real time is also an important feature, as health systems evolve by adopting more features and solving new problems. A module was installed in Centro Hospitalar do Porto, increasing the functionality and the overall usability of AIDA.

The Next Generation of Interoperability Agents in Healthcare

Directory of Open Access Journals (Sweden)

Luciana Cardoso

2014-05-01

Full Text Available Interoperability in health information systems is increasingly a requirement rather than an option. Standards and technologies, such as multi-agent systems, have proven to be powerful tools in interoperability issues. In the last few years, the authors have worked on developing the Agency for Integration, Diffusion and Archive of Medical Information (AIDA, which is an intelligent, agent-based platform to ensure interoperability in healthcare units. It is increasingly important to ensure the high availability and reliability of systems. The functions provided by the systems that treat interoperability cannot fail. This paper shows the importance of monitoring and controlling intelligent agents as a tool to anticipate problems in health information systems. The interaction between humans and agents through an interface that allows the user to create new agents easily and to monitor their activities in real time is also an important feature, as health systems evolve by adopting more features and solving new problems. A module was installed in Centro Hospitalar do Porto, increasing the functionality and the overall usability of AIDA.

Organic Colouring Agents in the Pharmaceutical Industry

Directory of Open Access Journals (Sweden)

Šuleková M.

2017-09-01

Full Text Available Food dyes are largely used in the process of manufacturing pharmaceutical products. The aim of such a procedure is not only to increase the attractiveness of products, but also to help patients distinguish between pharmaceuticals. Various dyes, especially organic colouring agents, may in some cases have a negative impact on the human body. They are incorporated into pharmaceutical products including tablets, hard gelatine capsules or soft gelatine capsules, lozenges, syrups, etc. This article provides an overview of the most widely used colouring agents in pharmaceuticals, their characteristics and the EU legislation which regulates their use.

Evaluating mice lacking serum carboxylesterase as a behavioral model for nerve agent intoxication.

Science.gov (United States)

Dunn, Emily N; Ferrara-Bowens, Teresa M; Chachich, Mark E; Honnold, Cary L; Rothwell, Cristin C; Hoard-Fruchey, Heidi M; Lesyna, Catherine A; Johnson, Erik A; Cerasoli, Douglas M; McDonough, John H; Cadieux, C Linn

2018-06-07

Mice and other rodents are typically utilized for chemical warfare nerve agent research. Rodents have large amounts of carboxylesterase in their blood, while humans do not. Carboxylesterase nonspecifically binds to and detoxifies nerve agent. The presence of this natural bioscavenger makes mice and other rodents poor models for studies identifying therapeutics to treat humans exposed to nerve agents. To obviate this problem, a serum carboxylesterase knockout (Es1 KO) mouse was created. In this study, Es1 KO and wild type (WT) mice were assessed for differences in gene expression, nerve agent (soman; GD) median lethal dose (MLD) values, and behavior prior to and following nerve agent exposure. No expression differences were detected between Es1 KO and WT mice in more than 34 000 mouse genes tested. There was a significant difference between Es1 KO and WT mice in MLD values, as the MLD for GD-exposed WT mice was significantly higher than the MLD for GD-exposed Es1 KO mice. Behavioral assessments of Es1 KO and WT mice included an open field test, a zero maze, a Barnes maze, and a sucrose preference test (SPT). While sex differences were observed in various measures of these tests, overall, Es1 KO mice behaved similarly to WT mice. The two genotypes also showed virtually identical neuropathological changes following GD exposure. Es1 KO mice appear to have an enhanced susceptibility to GD toxicity while retaining all other behavioral and physiological responses to this nerve agent, making the Es1 KO mouse a more human-like model for nerve agent research.

From Annotated Multimodal Corpora to Simulated Human-Like Behaviors

DEFF Research Database (Denmark)

Rehm, Matthias; André, Elisabeth

2008-01-01

Multimodal corpora prove useful at different stages of the development process of embodied conversational agents. Insights into human-human communicative behaviors can be drawn from such corpora. Rules for planning and generating such behavior in agents can be derived from this information....... And even the evaluation of human-agent interactions can rely on corpus data from human-human communication. In this paper, we exemplify how corpora can be exploited at the different development steps, starting with the question of how corpora are annotated and on what level of granularity. The corpus data...

A Multi-Agent Control Architecture for a Robotic Wheelchair

Directory of Open Access Journals (Sweden)

C. Galindo

2006-01-01

Full Text Available Assistant robots like robotic wheelchairs can perform an effective and valuable work in our daily lives. However, they eventually may need external help from humans in the robot environment (particularly, the driver in the case of a wheelchair to accomplish safely and efficiently some tricky tasks for the current technology, i.e. opening a locked door, traversing a crowded area, etc. This article proposes a control architecture for assistant robots designed under a multi-agent perspective that facilitates the participation of humans into the robotic system and improves the overall performance of the robot as well as its dependability. Within our design, agents have their own intentions and beliefs, have different abilities (that include algorithmic behaviours and human skills and also learn autonomously the most convenient method to carry out their actions through reinforcement learning. The proposed architecture is illustrated with a real assistant robot: a robotic wheelchair that provides mobility to impaired or elderly people.

Improving Agent Bidding in Power Stock Markets through a Data Mining Enhanced Agent Platform

Science.gov (United States)

Chrysopoulos, Anthony C.; Symeonidis, Andreas L.; Mitkas, Pericles A.

Like in any other auctioning environment, entities participating in Power Stock Markets have to compete against other in order to maximize own revenue. Towards the satisfaction of their goal, these entities (agents - human or software ones) may adopt different types of strategies - from na?ve to extremely complex ones - in order to identify the most profitable goods compilation, the appropriate price to buy or sell etc, always under time pressure and auction environment constraints. Decisions become even more difficult to make in case one takes the vast volumes of historical data available into account: goods’ prices, market fluctuations, bidding habits and buying opportunities. Within the context of this paper we present Cassandra, a multi-agent platform that exploits data mining, in order to extract efficient models for predicting Power Settlement prices and Power Load values in typical Day-ahead Power markets. The functionality of Cassandra is discussed, while focus is given on the bidding mechanism of Cassandra’s agents, and the way data mining analysis is performed in order to generate the optimal forecasting models. Cassandra has been tested in a real-world scenario, with data derived from the Greek Energy Stock market.

Sphericall: A Human/Artificial Intelligence interaction experience

Directory of Open Access Journals (Sweden)

Frack Gechter

2014-12-01

Full Text Available Multi-agent systems are now wide spread in scientific works and in industrial applications. Few applications deal with the Human/Multi-agent system interaction. Multi-agent systems are characterized by individual entities, called agents, in interaction with each other and with their environment. Multi-agent systems are generally classified into complex systems categories since the global emerging phenomenon cannot be predicted even if every component is well known. The systems developed in this paper are named reactive because they behave using simple interaction models. In the reactive approach, the issue of Human/system interaction is hard to cope with and is scarcely exposed in literature. This paper presents Sphericall, an application aimed at studying Human/Complex System interactions and based on two physics inspired multi-agent systems interacting together. The Sphericall device is composed of a tactile screen and a spherical world where agents evolve. This paper presents both the technical background of Sphericall project and a feedback taken from the demonstration performed during OFFF Festival in La Villette (Paris.

Fostering relatedness between children and virtual agents through reciprocal self-disclosure

NARCIS (Netherlands)

Burger, F.; Broekens, J.; Neerincx, M.A.

2017-01-01

A key challenge in developing companion agents for children is keeping them interested after novelty effects wear off. Self Determination Theory posits that motivation is sustained if the human feels related to another human. According to Social Penetration Theory, relatedness can be established

Canine vector-borne co-infections: Ehrlichia canis and Hepatozoon canis in the same host monocytes.

Science.gov (United States)

Baneth, Gad; Harrus, Shimon; Gal, Arnon; Aroch, Itamar

2015-02-28

The protozoon Hepatozoon canis and the rickettsia Ehrlichia canis are tick-borne pathogens, transmitted by Rhipicephalus sanguineus, which cause canine hepatozoonosis and canine monocytic ehrlichiosis, respectively. Co-infection of the same host monocytes with H. canis and E. canis confirmed by molecular characterization of the infecting agents and quantitative assessment of co-infected cells is described for the first time in three naturally-infected dogs. Blood smear evaluation indicated that at least 50% of the leukocytes infected with H. canis gamonts contained E. canis morulae. Co-infection of the same host cell demonstrated in this report suggests that infection with one pathogen may permit or enhance invasion or prolonged cellular survival of the other. Copyright © 2014 Elsevier B.V. All rights reserved.

From multicultural agents to culture‐aware robots

DEFF Research Database (Denmark)

Rehm, Matthias

2013-01-01

In previous research we showed how a cross‐cultural multimodal corpus of human face to face interactions can serve as empirical foundation for implementing multicultural agents (e.g. Rehm et al. 2009). To this end, the corpus has been annotated in relation to a number of communicative phenomena...... of the system have to create the behavior themselves, allowing us to collect a cross‐cultural database of behavioral parameters for the robotic system under development. This reduces any subjective or cultural bias that was previously introduced. Instead, the cross‐cultural database of behavioral parameters......, there have always been some discomforts about it due to the following reasons: - Subjectivity of the annotation - Cultural bias of the annotation and the implementation/design of the agents - Applicability of results to agents (they might represent a culture of their own) Meanwhile, we have moved to physical...

Large-scale agent-based social simulation : A study on epidemic prediction and control

NARCIS (Netherlands)

Zhang, M.

2016-01-01

Large-scale agent-based social simulation is gradually proving to be a versatile methodological approach for studying human societies, which could make contributions from policy making in social science, to distributed artificial intelligence and agent technology in computer science, and to theory

Non-malignant disease mortality in meat workers: a model for studying the role of zoonotic transmissible agents in non-malignant chronic diseases in humans.

Science.gov (United States)

Johnson, E S; Zhou, Y; Sall, M; Faramawi, M El; Shah, N; Christopher, A; Lewis, N

2007-12-01

Current research efforts have mainly concentrated on evaluating the role of substances present in animal food in the aetiology of chronic diseases in humans, with relatively little attention given to evaluating the role of transmissible agents that are also present. Meat workers are exposed to a variety of transmissible agents present in food animals and their products. This study investigates mortality from non-malignant diseases in workers with these exposures. A cohort mortality study was conducted between 1949 and 1989, of 8520 meat workers in a union in Baltimore, Maryland, who worked in manufacturing plants where animals were killed or processed, and who had high exposures to transmissible agents. Mortality in meat workers was compared with that in a control group of 6081 workers in the same union, and also with the US general population. Risk was estimated by proportional mortality and standardised mortality ratios (SMRs) and relative SMR. A clear excess of mortality from septicaemia, subarachnoid haemorrhage, chronic nephritis, acute and subacute endocarditis, functional diseases of the heart, and decreased risk of mortality from pre-cerebral, cerebral artery stenosis were observed in meat workers when compared to the control group or to the US general population. The authors hypothesise that zoonotic transmissible agents present in food animals and their products may be responsible for the occurrence of some cases of circulatory, neurological and other diseases in meat workers, and possibly in the general population exposed to these agents.

Socio-Ecohydrologic Agents And Services: Integrating Human And Natural Components To Address Coupled System Resilience

Science.gov (United States)

Pavao-zuckerman, M.; Pope, A.; Chan, D.; Curl, K.; Gimblett, H. R.; Hough, M.; House-Peters, L.; Lee, R.; Scott, C. A.

2012-12-01

Riparian corridors in arid regions are highly valued for their relative scarcity, and because healthy riparian systems support high levels of biodiversity, can meet human demand for water and water-related resources and functions. Our team is taking a transdiciplinary social-ecological systems approach to assessing riparian corridor resilience in two watersheds (the San Pedro River in USA and Mexico, and the Rio San Miguel in Mexico) through a project funded by the NSF CNH program ("Strengthening Resilience of Arid Region Riparian Corridors"). Multiple perspectives are integrated in the project, including hydrology, ecology, institutional dynamics, and decision making (at the level of both policy and individual choice), as well as the perspectives of various stakeholder groups and individuals in the watersheds. Here we discuss initial findings that center around linking changes in ecohydrology and livelihoods related to decisions in response to climatic, ecological, and social change. The research team is implementing two approaches to integrate the disparate disciplines participating in the research (and the varied perspectives among the stakeholders in this binational riparian context): (1) ecosystem service assessment, and (2) agent based model simulation. We are developing an ecosystem service perspective that provides a bridge between ecological dynamics in the landscape and varied stakeholder perspectives on the implications of ecohydrology for well-being (economic, cultural, ecological). Services are linked on one hand to the spatial patterns of traits of individuals within species (allowing a more predictive application of ecosystem services as they vary with community change in time), and to stakeholder perspectives (facilitating integration of ecosystem services into our understanding of decision making processes) in a case study in the San Pedro River National Conservation Area. The agent- based model (ABM) approach incorporates the influence of human

Wonder world of phages: potential biocontrol agents safeguarding biosphere and health of animals and humans- current scenario and perspectives.

Science.gov (United States)

Tiwari, Ruchi; Chakraborty, Sandip; Dhama, Kuldeep; Wani, Mohd Yaqoob; Kumar, Amit; Kapoor, Sanjay

2014-02-01

Darwin's theory of natural selection and concept of survival of fittest of Wallace is a universal truth which derives the force of life among all live entities on this biosphere. Issues regarding food safety along with increased drug resistance and emerging zoonotic infections have proved that multidisciplinary efforts are in demand for human and animal welfare. This has led to development of various novel therapies the list of which remains incomplete without mentioning about phages. Homologous and non-homologous recombination along with point mutation and addition of new genes play role in their evolution. The rapid emergence of the antibiotic resistant strains of bacteria have created keen interest in finding necessary alternatives to check microbial infections and there comes the importance of phages. Phages kill the bacteria either by lysis or by releasing holins. Bacteriophages; the viruses that live on bacteria are nowadays considered as the best biocontrol agents. They are used as replacers of antibiotics; food industry promoter; guard of aquatic life as well as of plants; pre-slaughter treatment agents; Generally Recognized As Safe (GRAS) food additives; Typing agent of bacteria; active tool of super bug therapy; in post harvest crops and food and during post infection and also to combat intracellular pathogens viz. Mycobacteria and Mycoplasma. Cyanophages/phycophages are particularly useful in controlling blooms produced by various genera of algae and cyanobacteria. By performing centrifugation studies and based on electron microscopy certain virus like particles containing ds RNA have been confirmed as mycophages. They are well proven as threat to pathogenic fungi (both fungal hyphae and yeast). Those that infect yeasts are called zymophages. Virophages have exquisite specificity for their viral host, hence can extensively be used for genetic studies and can also act as evolutionary link. After the discovery of very first virophage till now, a total of 3

Suppression of NRF2–ARE activity sensitizes chemotherapeutic agent-induced cytotoxicity in human acute monocytic leukemia cells

International Nuclear Information System (INIS)

Peng, Hui; Wang, Huihui; Xue, Peng; Hou, Yongyong; Dong, Jian; Zhou, Tong; Qu, Weidong; Peng, Shuangqing; Li, Jin; Carmichael, Paul L.; Nelson, Bud; Clewell, Rebecca; Zhang, Qiang; Andersen, Melvin E.; Pi, Jingbo

2016-01-01

Nuclear factor erythroid 2-related factor 2 (NRF2), a master regulator of the antioxidant response element (ARE)-dependent transcription, plays a pivotal role in chemical detoxification in normal and tumor cells. Consistent with previous findings that NRF2–ARE contributes to chemotherapeutic resistance of cancer cells, we found that stable knockdown of NRF2 by lentiviral shRNA in human acute monocytic leukemia (AML) THP-1 cells enhanced the cytotoxicity of several chemotherapeutic agents, including arsenic trioxide (As 2 O 3 ), etoposide and doxorubicin. Using an ARE-luciferase reporter expressed in several human and mouse cells, we identified a set of compounds, including isonicotinic acid amides, isoniazid and ethionamide, that inhibited NRF2–ARE activity. Treatment of THP-1 cells with ethionamide, for instance, significantly reduced mRNA expression of multiple ARE-driven genes under either basal or As 2 O 3 -challenged conditions. As determined by cell viability and cell cycle, suppression of NRF2–ARE by ethionamide also significantly enhanced susceptibility of THP-1 and U937 cells to As 2 O 3 -induced cytotoxicity. In THP-1 cells, the sensitizing effect of ethionamide on As 2 O 3 -induced cytotoxicity was highly dependent on NRF2. To our knowledge, the present study is the first to demonstrate that ethionamide suppresses NRF2–ARE signaling and disrupts the transcriptional network of the antioxidant response in AML cells, leading to sensitization to chemotherapeutic agents. - Highlights: • Identification of novel inhibitors of ARE-dependent transcription • Suppression of NRF2–ARE sensitizes THP-1 cells to chemotherapy. • Ethionamide suppresses ARE-dependent transcriptional activity. • Ethionamide and isoniazid increase the cytotoxicity of As 2 O 3 in AML cells. • Sensitization of THP-1 cells to As 2 O 3 toxicity by ethionamide is NRF2-dependent.

Behavior acquisition in artificial agents

OpenAIRE

Thurau, Christian

2006-01-01

Computational skill acquisition in robots and simulated agents has been a topic of increasing popularity throughout the last years. Despite impressive progress, autonomous behavior at a level of animals and humans are not yet replicated by machines. Especially when a complex environment demands versatile, goal-oriented behavior, current artificial systems show shortcomings. Consider for instance modern 3D computer games. Despite their key role for more emersive game experience, surprisingly l...

An Integrated Agent Model Addressing Situation Awareness and Functional State in Decision Making

NARCIS (Netherlands)

Hoogendoorn, M.; van Lambalgen, R.M.; Treur, J.

2011-01-01

In this paper, an integrated agent model is introduced addressing mutually interacting Situation Awareness and Functional State dynamics in decision making. This shows how a human's functional state, more specific a human's exhaustion and power, can influence a human's situation awareness, and in

Prediction of a Therapeutic Dose for Buagafuran, a Potent Anxiolytic Agent by Physiologically Based Pharmacokinetic/Pharmacodynamic Modeling Starting from Pharmacokinetics in Rats and Human

Directory of Open Access Journals (Sweden)

Fen Yang

2017-10-01

Full Text Available Physiologically based pharmacokinetic (PBPK/pharmacodynamic (PD models can contribute to animal-to-human extrapolation and therapeutic dose predictions. Buagafuran is a novel anxiolytic agent and phase I clinical trials of buagafuran have been completed. In this paper, a potentially effective dose for buagafuran of 30 mg t.i.d. in human was estimated based on the human brain concentration predicted by a PBPK/PD modeling. The software GastroPlusTM was used to build the PBPK/PD model for buagafuran in rat which related the brain tissue concentrations of buagafuran and the times of animals entering the open arms in the pharmacological model of elevated plus-maze. Buagafuran concentrations in human plasma were fitted and brain tissue concentrations were predicted by using a human PBPK model in which the predicted plasma profiles were in good agreement with observations. The results provided supportive data for the rational use of buagafuran in clinic.

Identification of Novel 5,6-Dimethoxyindan-1-one Derivatives as Antiviral Agents.

Science.gov (United States)

Patil, Siddappa A; Patil, Vikrant; Patil, Renukadevi; Beaman, Kenneth; Patil, Shivaputra A

2017-01-01

Discovery of novel antiviral agents is essential because viral infection continues to threaten human life globally. Various heterocyclic small molecules have been developed as antiviral agents. The 5,6-dimethoxyindan-1-on nucleus is of considerable interest as this ring is the key constituent in a range of bioactive compounds, both naturally occurring and synthetic, and often of considerable complexity. The main purpose of this research was to discover and develop small molecule heterocycles as broad-spectrum of antiviral agents. A focused small set of 5,6-dimethoxyindan-1-one analogs (6-8) along with a thiopene derivative (9) was screened for selected viruses (Vaccinia virus - VACA, Human papillomavirus - HPV, Zika virus - ZIKV, Dengue virus - DENV, Measles virus - MV, Poliovirus 3 - PV, Rift Valley fever virus - RVFV, Tacaribe virus - TCRV, Venezuelan equine encephalitis virus - VEEV, Herpes simplex virus 1 -HSV-1 and Human cytomegalovirus - HCMV) using the National Institute of Allergy and Infectious Diseases (NIAID)'s Division of Microbiology and Infectious Diseases (DMID) antiviral screening program. These molecules demonstrated moderate to excellent antiviral activity towards variety of viruses. The 5,6-dimethoxyindan-1-one analog (7) demonstrated high efficacy towards vaccinia virus (EC50: 30.00 µM) in secondary plaque reduction assay. The thiophene analog (9) has shown very good viral inhibition towards several viruses such as Human papillomavirus, Measles virus, Rift Valley fever virus, Tacaribe virus and Herpes simplex virus 1. Our research identified a novel 5,6-dimethoxyindan-1-one analog (compound 7), as a potent antiviral agent for vaccinia virus, and heterocyclic chalcone analog (compound 9) as a broad spectrum antiviral agent. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Agent Programming Languages and Logics in Agent-Based Simulation

DEFF Research Database (Denmark)

Larsen, John

2018-01-01

and social behavior, and work on verification. Agent-based simulation is an approach for simulation that also uses the notion of agents. Although agent programming languages and logics are much less used in agent-based simulation, there are successful examples with agents designed according to the BDI...

Subcellular SIMS imaging of gadolinium isotopes in human glioblastoma cells treated with a gadolinium containing MRI agent

Science.gov (United States)

Smith, Duane R.; Lorey, Daniel R.; Chandra, Subhash

2004-06-01

Neutron capture therapy is an experimental binary radiotherapeutic modality for the treatment of brain tumors such as glioblastoma multiforme. Recently, neutron capture therapy with gadolinium-157 has gained attention, and techniques for studying the subcellular distribution of gadolinium-157 are needed. In this preliminary study, we have been able to image the subcellular distribution of gadolinium-157, as well as the other six naturally abundant isotopes of gadolinium, with SIMS ion microscopy. T98G human glioblastoma cells were treated for 24 h with 25 mg/ml of the metal ion complex diethylenetriaminepentaacetic acid Gd(III) dihydrogen salt hydrate (Gd-DTPA). Gd-DTPA is a contrast enhancing agent used for MRI of brain tumors, blood-brain barrier impairment, diseases of the central nervous system, etc. A highly heterogeneous subcellular distribution was observed for gadolinium-157. The nuclei in each cell were distinctly lower in gadolinium-157 than in the cytoplasm. Even within the cytoplasm the gadolinium-157 was heterogeneously distributed. The other six naturally abundant isotopes of gadolinium were imaged from the same cells and exhibited a subcellular distribution consistent with that observed for gadolinium-157. These observations indicate that SIMS ion microscopy may be a viable approach for subcellular studies of gadolinium containing neutron capture therapy drugs and may even play a major role in the development and validation of new gadolinium contrast enhancing agents for diagnostic MRI applications.

Engineered collagen hydrogels for the sustained release of biomolecules and imaging agents: promoting the growth of human gingival cells.

Science.gov (United States)

Choi, Jonghoon; Park, Hoyoung; Kim, Taeho; Jeong, Yoon; Oh, Myoung Hwan; Hyeon, Taeghwan; Gilad, Assaf A; Lee, Kwan Hyi

2014-01-01

We present here the in vitro release profiles of either fluorescently labeled biomolecules or computed tomography contrast nanoagents from engineered collagen hydrogels under physiological conditions. The collagen constructs were designed as potential biocompatible inserts into wounded human gingiva. The collagen hydrogels were fabricated under a variety of conditions in order to optimize the release profile of biomolecules and nanoparticles for the desired duration and amount. The collagen constructs containing biomolecules/nanoconstructs were incubated under physiological conditions (ie, 37°C and 5% CO2) for 24 hours, and the release profile was tuned from 20% to 70% of initially loaded materials by varying the gelation conditions of the collagen constructs. The amounts of released biomolecules and nanoparticles were quantified respectively by measuring the intensity of fluorescence and X-ray scattering. The collagen hydrogel we fabricated may serve as an efficient platform for the controlled release of biomolecules and imaging agents in human gingiva to facilitate the regeneration of oral tissues.

Scopolamine provocation-based pharmacological MRI model for testing procognitive agents.

Science.gov (United States)

Hegedűs, Nikolett; Laszy, Judit; Gyertyán, István; Kocsis, Pál; Gajári, Dávid; Dávid, Szabolcs; Deli, Levente; Pozsgay, Zsófia; Tihanyi, Károly

2015-04-01

There is a huge unmet need to understand and treat pathological cognitive impairment. The development of disease modifying cognitive enhancers is hindered by the lack of correct pathomechanism and suitable animal models. Most animal models to study cognition and pathology do not fulfil either the predictive validity, face validity or construct validity criteria, and also outcome measures greatly differ from those of human trials. Fortunately, some pharmacological agents such as scopolamine evoke similar effects on cognition and cerebral circulation in rodents and humans and functional MRI enables us to compare cognitive agents directly in different species. In this paper we report the validation of a scopolamine based rodent pharmacological MRI provocation model. The effects of deemed procognitive agents (donepezil, vinpocetine, piracetam, alpha 7 selective cholinergic compounds EVP-6124, PNU-120596) were compared on the blood-oxygen-level dependent responses and also linked to rodent cognitive models. These drugs revealed significant effect on scopolamine induced blood-oxygen-level dependent change except for piracetam. In the water labyrinth test only PNU-120596 did not show a significant effect. This provocational model is suitable for testing procognitive compounds. These functional MR imaging experiments can be paralleled with human studies, which may help reduce the number of false cognitive clinical trials. © The Author(s) 2015.

Biological agents with potential for misuse: a historical perspective and defensive measures

International Nuclear Information System (INIS)

Bhalla, Deepak K.; Warheit, David B.

2004-01-01

Biological and chemical agents capable of producing serious illness or mortality have been used in biowarfare from ancient times. Use of these agents has progressed from crude forms in early and middle ages, when snakes and infected cadavers were used as weapons in battles, to sophisticated preparations for use during and after the second World War. Cults and terrorist organizations have attempted the use of biological agents with an aim to immobilize populations or cause serious harm. The reasons for interest in these agents by individuals and organizations include relative ease of acquisition, potential for causing mass casualty or panic, modest financing requirement, availability of technology, and relative ease of delivery. The Centers for Disease Control and Prevention has classified Critical Biological Agents into three major categories. This classification was based on several criteria, which include severity of impact on human health, potential for delivery in a weapon, capacity to cause panic and special needs for development, and stockpiling of medication. Agents that could cause the greatest harm following deliberate use were placed in category A. Category B included agents capable of producing serious harm and significant mortality but of lower magnitude than category A agents. Category C included emerging pathogens that could be developed for mass dispersion in future and their potential as a major health threat. A brief description of the category A bioagents is included and the pathophysiology of two particularly prominent agents, namely anthrax and smallpox, is discussed in detail. The potential danger from biological agents and their ever increasing threat to human populations have created a need for developing technologies for their early detection, for developing treatment strategies, and for refinement of procedures to ensure survival of affected individuals so as to attain the ultimate goal of eliminating the threat from intentional use of

Biological agents with potential for misuse: a historical perspective and defensive measures.

Science.gov (United States)

Bhalla, Deepak K; Warheit, David B

2004-08-15

Biological and chemical agents capable of producing serious illness or mortality have been used in biowarfare from ancient times. Use of these agents has progressed from crude forms in early and middle ages, when snakes and infected cadavers were used as weapons in battles, to sophisticated preparations for use during and after the second World War. Cults and terrorist organizations have attempted the use of biological agents with an aim to immobilize populations or cause serious harm. The reasons for interest in these agents by individuals and organizations include relative ease of acquisition, potential for causing mass casualty or panic, modest financing requirement, availability of technology, and relative ease of delivery. The Centers for Disease Control and Prevention has classified Critical Biological Agents into three major categories. This classification was based on several criteria, which include severity of impact on human health, potential for delivery in a weapon, capacity to cause panic and special needs for development, and stockpiling of medication. Agents that could cause the greatest harm following deliberate use were placed in category A. Category B included agents capable of producing serious harm and significant mortality but of lower magnitude than category A agents. Category C included emerging pathogens that could be developed for mass dispersion in future and their potential as a major health threat. A brief description of the category A bioagents is included and the pathophysiology of two particularly prominent agents, namely anthrax and smallpox, is discussed in detail. The potential danger from biological agents and their ever increasing threat to human populations have created a need for developing technologies for their early detection, for developing treatment strategies, and for refinement of procedures to ensure survival of affected individuals so as to attain the ultimate goal of eliminating the threat from intentional use of

MULTI AGENT-BASED ENVIRONMENTAL LANDSCAPE (MABEL) - AN ARTIFICIAL INTELLIGENCE SIMULATION MODEL: SOME EARLY ASSESSMENTS

OpenAIRE

Alexandridis, Konstantinos T.; Pijanowski, Bryan C.

2002-01-01

The Multi Agent-Based Environmental Landscape model (MABEL) introduces a Distributed Artificial Intelligence (DAI) systemic methodology, to simulate land use and transformation changes over time and space. Computational agents represent abstract relations among geographic, environmental, human and socio-economic variables, with respect to land transformation pattern changes. A multi-agent environment is developed providing task-nonspecific problem-solving abilities, flexibility on achieving g...

Antioxidant and antigenotoxic role of recombinant human erythropoeitin against alkylating agents: cisplatin and mitomycin C in cultured Vero cells.

Science.gov (United States)

Rjiba-Touati, Karima; Ayed-Boussema, Imen; Soualeh, Nidhal; Achour, Abdellatif; Bacha, Hassen; Abid, Salwa

2013-08-01

Cisplatin (CDDP) and mitomycin C (MMC), two alkylating agents used against various solid tumours, are a common source of acute kidney injury. Thus, strategies for minimizing CDDP and MMC toxicity are of a clinical interest. In this study, we aimed to investigate the protective role of recombinant human erythropoietin (rhEPO) against oxidative stress and genotoxicity induced by CDDP and MMC in cultured Vero cells. Three types of treatments were performed: (i) cells were treated with rhEPO 24 h before exposure to CDDP/MMC (pre-treatment), (ii) cells were treated with rhEPO and CDDP/MMC simultaneously (co-treatment), (iii) cells were treated with rhEPO 24 h after exposure to CDDP/MMC (post-treatment). Our results showed that rhEPO decreased the reactive oxygen species levels, the malondialdehyde levels and ameliorated glutathione (reduced and oxidized glutathione) modulation induced by CDDP and MMC in cultured Vero cells. Furthermore, rhEPO administration prevented alkylating agents-induced DNA damage accessed by comet test. Altogether, our results suggested a protective role of rhEPO, against CDDP- and MMC-induced oxidative stress and genotoxicity, especially in pre-treatment condition.

The pharmacology and toxicology of three new biologic agents used in pulmonary medicine.

Science.gov (United States)

Albertson, T E; Walby, W F; Allen, R P; Tharratt, R S

1995-01-01

Biological agents have played an important role in the evolution of modern medical therapeutics. Recent advances in biologicals have in part been stimulated by the biotechnology revolution seen over the last several years. Toxicologists need to be aware of the proposed mechanisms and approved and experimental uses of these new biologic agents. Further, controversies about their use, efficacy, cost issues and potential toxicities should be known. Often these drugs are designed for small patient populations thus limiting the availability of human toxicological data bases. This paper reviews the pharmacology and toxicology of three new biologics (recombinant human DNase I, alpha 1-protease inhibitor, and nitric oxide). These agents appear to have important roles in treating specific diseases or disease states seen in pulmonary medicine.

Agents unleashed a public domain look at agent technology

CERN Document Server

Wayner, Peter

1995-01-01

Agents Unleashed: A Public Domain Look at Agent Technology covers details of building a secure agent realm. The book discusses the technology for creating seamlessly integrated networks that allow programs to move from machine to machine without leaving a trail of havoc; as well as the technical details of how an agent will move through the network, prove its identity, and execute its code without endangering the host. The text also describes the organization of the host's work processing an agent; error messages, bad agent expulsion, and errors in XLISP-agents; and the simulators of errors, f

A new malaria agent in African hominids.

Directory of Open Access Journals (Sweden)

Benjamin Ollomo

2009-05-01

Full Text Available Plasmodium falciparum is the major human malaria agent responsible for 200 to 300 million infections and one to three million deaths annually, mainly among African infants. The origin and evolution of this pathogen within the human lineage is still unresolved. A single species, P. reichenowi, which infects chimpanzees, is known to be a close sister lineage of P. falciparum. Here we report the discovery of a new Plasmodium species infecting Hominids. This new species has been isolated in two chimpanzees (Pan troglodytes kept as pets by villagers in Gabon (Africa. Analysis of its complete mitochondrial genome (5529 nucleotides including Cyt b, Cox I and Cox III genes reveals an older divergence of this lineage from the clade that includes P. falciparum and P. reichenowi (approximately 21+/-9 Myrs ago using Bayesian methods and considering that the divergence between P. falciparum and P. reichenowi occurred 4 to 7 million years ago as generally considered in the literature. This time frame would be congruent with the radiation of hominoids, suggesting that this Plasmodium lineage might have been present in early hominoids and that they may both have experienced a simultaneous diversification. Investigation of the nuclear genome of this new species will further the understanding of the genetic adaptations of P. falciparum to humans. The risk of transfer and emergence of this new species in humans must be now seriously considered given that it was found in two chimpanzees living in contact with humans and its close relatedness to the most virulent agent of malaria.

I Reach Faster When I See You Look: Gaze Effects in Human-Human and Human-Robot Face-to-Face Cooperation.

Science.gov (United States)

Boucher, Jean-David; Pattacini, Ugo; Lelong, Amelie; Bailly, Gerrard; Elisei, Frederic; Fagel, Sascha; Dominey, Peter Ford; Ventre-Dominey, Jocelyne

2012-01-01

Human-human interaction in natural environments relies on a variety of perceptual cues. Humanoid robots are becoming increasingly refined in their sensorimotor capabilities, and thus should now be able to manipulate and exploit these social cues in cooperation with their human partners. Previous studies have demonstrated that people follow human and robot gaze, and that it can help them to cope with spatially ambiguous language. Our goal is to extend these findings into the domain of action, to determine how human and robot gaze can influence the speed and accuracy of human action. We report on results from a human-human cooperation experiment demonstrating that an agent's vision of her/his partner's gaze can significantly improve that agent's performance in a cooperative task. We then implement a heuristic capability to generate such gaze cues by a humanoid robot that engages in the same cooperative interaction. The subsequent human-robot experiments demonstrate that a human agent can indeed exploit the predictive gaze of their robot partner in a cooperative task. This allows us to render the humanoid robot more human-like in its ability to communicate with humans. The long term objectives of the work are thus to identify social cooperation cues, and to validate their pertinence through implementation in a cooperative robot. The current research provides the robot with the capability to produce appropriate speech and gaze cues in the context of human-robot cooperation tasks. Gaze is manipulated in three conditions: Full gaze (coordinated eye and head), eyes hidden with sunglasses, and head fixed. We demonstrate the pertinence of these cues in terms of statistical measures of action times for humans in the context of a cooperative task, as gaze significantly facilitates cooperation as measured by human response times.

Agent-Based Crowd Simulation Considering Emotion Contagion for Emergency Evacuation Problem

Science.gov (United States)

Faroqi, H.; Mesgari, M.-S.

2015-12-01

During emergencies, emotions greatly affect human behaviour. For more realistic multi-agent systems in simulations of emergency evacuations, it is important to incorporate emotions and their effects on the agents. In few words, emotional contagion is a process in which a person or group influences the emotions or behavior of another person or group through the conscious or unconscious induction of emotion states and behavioral attitudes. In this study, we simulate an emergency situation in an open square area with three exits considering Adults and Children agents with different behavior. Also, Security agents are considered in order to guide Adults and Children for finding the exits and be calm. Six levels of emotion levels are considered for each agent in different scenarios and situations. The agent-based simulated model initialize with the random scattering of agent populations and then when an alarm occurs, each agent react to the situation based on its and neighbors current circumstances. The main goal of each agent is firstly to find the exit, and then help other agents to find their ways. Numbers of exited agents along with their emotion levels and damaged agents are compared in different scenarios with different initialization in order to evaluate the achieved results of the simulated model. NetLogo 5.2 is used as the multi-agent simulation framework with R language as the developing language.

AGENT-BASED CROWD SIMULATION CONSIDERING EMOTION CONTAGION FOR EMERGENCY EVACUATION PROBLEM

Directory of Open Access Journals (Sweden)

H. Faroqi

2015-12-01

Full Text Available During emergencies, emotions greatly affect human behaviour. For more realistic multi-agent systems in simulations of emergency evacuations, it is important to incorporate emotions and their effects on the agents. In few words, emotional contagion is a process in which a person or group influences the emotions or behavior of another person or group through the conscious or unconscious induction of emotion states and behavioral attitudes. In this study, we simulate an emergency situation in an open square area with three exits considering Adults and Children agents with different behavior. Also, Security agents are considered in order to guide Adults and Children for finding the exits and be calm. Six levels of emotion levels are considered for each agent in different scenarios and situations. The agent-based simulated model initialize with the random scattering of agent populations and then when an alarm occurs, each agent react to the situation based on its and neighbors current circumstances. The main goal of each agent is firstly to find the exit, and then help other agents to find their ways. Numbers of exited agents along with their emotion levels and damaged agents are compared in different scenarios with different initialization in order to evaluate the achieved results of the simulated model. NetLogo 5.2 is used as the multi-agent simulation framework with R language as the developing language.

Mechanisms of chemoresistance to alkylating agents in malignant glioma.

Science.gov (United States)

Sarkaria, Jann N; Kitange, Gaspar J; James, C David; Plummer, Ruth; Calvert, Hilary; Weller, Michael; Wick, Wolfgang

2008-05-15

Intrinsic or acquired chemoresistance to alkylating agents is a major cause of treatment failure in patients with malignant brain tumors. Alkylating agents, the mainstay of treatment for brain tumors, damage the DNA and induce apoptosis, but the cytotoxic activity of these agents is dependent on DNA repair pathways. For example, O6-methylguanine DNA adducts can cause double-strand breaks, but this is dependent on a functional mismatch repair pathway. Thus, tumor cell lines deficient in mismatch repair are resistant to alkylating agents. Perhaps the most important mechanism of resistance to alkylating agents is the DNA repair enzyme O6-methylguanine methyltransferase, which can eliminate the cytotoxic O6-methylguanine DNA adduct before it causes harm. Another mechanism of resistance to alkylating agents is the base excision repair (BER) pathway. Consequently, efforts are ongoing to develop effective inhibitors of BER. Poly(ADP-ribose)polymerase plays a pivotal role in BER and is an important therapeutic target. Developing effective strategies to overcome chemoresistance requires the identification of reliable preclinical models that recapitulate human disease and which can be used to facilitate drug development. This article describes the diverse mechanisms of chemoresistance operating in malignant glioma and efforts to develop reliable preclinical models and novel pharmacologic approaches to overcome resistance to alkylating agents.

Agent-Centered Decision Making in Normal and Abnormal Cognition

Directory of Open Access Journals (Sweden)

Goldberg, Elkhonon

2012-08-01

Full Text Available Much of human cognition is “agent-centered,” subjective, and in that sense relative, directed at deciding, “What is best for me”. This is very different from “veridical” cognition, directed at finding an objectively correct solution inherent in the task and independent of the agent. The frontal lobes in particular are central to agent-centered decision making. Yet very little is available in the arsenal of cognitive paradigms used in the cognitive neuroscience research and in clinical neuropsychology test design to examine “agent-centered” decision making. Current paradigms and tests used to measure decision making clinically and experimentally are veridical in nature and as such miss the essence of “agent-centered” cognition. The dearth of “agent-centered” cognitive paradigms severely limits our ability to understand fully the function and dysfunction of the frontal lobes. The Cognitive Bias Task (CBT is an agent-centered paradigm designed to fill this gap. CBT has been used as a cognitive activation task in fMRI, SPECT, and EEG, as well as in studies of normal development, addiction, dementia, focal lesions, and schizophrenia. This resulted in a range of findings that eluded more traditional “veridical” paradigms and are reviewed here.

Geometry of behavioral spaces: A computational approach to analysis and understanding of agent based models and agent behaviors

Science.gov (United States)

Cenek, Martin; Dahl, Spencer K.

2016-11-01

Systems with non-linear dynamics frequently exhibit emergent system behavior, which is important to find and specify rigorously to understand the nature of the modeled phenomena. Through this analysis, it is possible to characterize phenomena such as how systems assemble or dissipate and what behaviors lead to specific final system configurations. Agent Based Modeling (ABM) is one of the modeling techniques used to study the interaction dynamics between a system's agents and its environment. Although the methodology of ABM construction is well understood and practiced, there are no computational, statistically rigorous, comprehensive tools to evaluate an ABM's execution. Often, a human has to observe an ABM's execution in order to analyze how the ABM functions, identify the emergent processes in the agent's behavior, or study a parameter's effect on the system-wide behavior. This paper introduces a new statistically based framework to automatically analyze agents' behavior, identify common system-wide patterns, and record the probability of agents changing their behavior from one pattern of behavior to another. We use network based techniques to analyze the landscape of common behaviors in an ABM's execution. Finally, we test the proposed framework with a series of experiments featuring increasingly emergent behavior. The proposed framework will allow computational comparison of ABM executions, exploration of a model's parameter configuration space, and identification of the behavioral building blocks in a model's dynamics.

Mobile Agent Data Integrity Using Multi-Agent Architecture

National Research Council Canada - National Science Library

McDonald, Jeffrey

2004-01-01

.... Security issues for mobile agents continue to produce research interest, particularly in developing mechanisms that guarantee protection of agent data and agent computations in the presence of malicious hosts...

Agent Based Modeling of Human Gut Microbiome Interactions and Perturbations.

Directory of Open Access Journals (Sweden)

Tatiana Shashkova

Full Text Available Intestinal microbiota plays an important role in the human health. It is involved in the digestion and protects the host against external pathogens. Examination of the intestinal microbiome interactions is required for understanding of the community influence on host health. Studies of the microbiome can provide insight on methods of improving health, including specific clinical procedures for individual microbial community composition modification and microbiota correction by colonizing with new bacterial species or dietary changes.In this work we report an agent-based model of interactions between two bacterial species and between species and the gut. The model is based on reactions describing bacterial fermentation of polysaccharides to acetate and propionate and fermentation of acetate to butyrate. Antibiotic treatment was chosen as disturbance factor and used to investigate stability of the system. System recovery after antibiotic treatment was analyzed as dependence on quantity of feedback interactions inside the community, therapy duration and amount of antibiotics. Bacterial species are known to mutate and acquire resistance to the antibiotics. The ability to mutate was considered to be a stochastic process, under this suggestion ratio of sensitive to resistant bacteria was calculated during antibiotic therapy and recovery.The model confirms a hypothesis of feedbacks mechanisms necessity for providing functionality and stability of the system after disturbance. High fraction of bacterial community was shown to mutate during antibiotic treatment, though sensitive strains could become dominating after recovery. The recovery of sensitive strains is explained by fitness cost of the resistance. The model demonstrates not only quantitative dynamics of bacterial species, but also gives an ability to observe the emergent spatial structure and its alteration, depending on various feedback mechanisms. Visual version of the model shows that spatial

How the human brain goes virtual: distinct cortical regions of the person-processing network are involved in self-identification with virtual agents.

Science.gov (United States)

Ganesh, Shanti; van Schie, Hein T; de Lange, Floris P; Thompson, Evan; Wigboldus, Daniël H J

2012-07-01

Millions of people worldwide engage in online role-playing with their avatar, a virtual agent that represents the self. Previous behavioral studies have indicated that many gamers identify more strongly with their avatar than with their biological self. Through their avatar, gamers develop social networks and learn new social-cognitive skills. The cognitive neurosciences have yet to identify the neural processes that underlie self-identification with these virtual agents. We applied functional neuroimaging to 22 long-term online gamers and 21 nongaming controls, while they rated personality traits of self, avatar, and familiar others. Strikingly, neuroimaging data revealed greater avatar-referential cortical activity in the left inferior parietal lobe, a region associated with self-identification from a third-person perspective. The magnitude of this brain activity correlated positively with the propensity to incorporate external body enhancements into one's bodily identity. Avatar-referencing furthermore recruited greater activity in the rostral anterior cingulate gyrus, suggesting relatively greater emotional self-involvement with one's avatar. Post-scanning behavioral data revealed superior recognition memory for avatar relative to others. Interestingly, memory for avatar positively covaried with play duration. These findings significantly advance our knowledge about the brain's plasticity to self-identify with virtual agents and the human cognitive-affective potential to live and learn in virtual worlds.

Between Complexity and Parsimony: Can Agent-Based Modelling Resolve the Trade-off

DEFF Research Database (Denmark)

Nielsen, Helle Ørsted; Malawska, Anna Katarzyna

2013-01-01

to BR- based policy studies would be to couple research on bounded ra-tionality with agent-based modeling. Agent-based models (ABMs) are computational models for simulating the behavior and interactions of any number of decision makers in a dynamic system. Agent-based models are better suited than...... are general equilibrium models for capturing behavior patterns of complex systems. ABMs may have the potential to represent complex systems without oversimplifying them. At the same time, research in bounded rationality and behavioral economics has already yielded many insights that could inform the modeling......While Herbert Simon espoused development of general models of behavior, he also strongly advo-cated that these models be based on realistic assumptions about humans and therefore reflect the complexity of human cognition and social systems (Simon 1997). Hence, the model of bounded rationality...

Novel Treatment of Staphylococcus aureus Device-Related Infections Using Fibrinolytic Agents.

Science.gov (United States)

Hogan, S; O'Gara, J P; O'Neill, E

2018-02-01

Staphylococcal infections involving biofilms represent a significant challenge in the treatment of patients with device-related infections. Staphylococcus aureus biofilms have been shown to be SaeRS regulated and dependent on the coagulase-catalyzed conversion of fibrinogen into fibrin on surfaces coated with human plasma. Here we investigated the treatment of staphylococcal biofilm device-related infections by digesting the fibrin biofilm matrix with and without existing antimicrobials. The fibrinolytic agents plasmin, streptokinase, and nattokinase, and TrypLE, a recombinant trypsin-like protease, were used to digest and treat S. aureus biofilms grown in vitro using in vivo -like static biofilm assays with and without antimicrobials. Cytotoxicity, the potential to induce a cytokine response in whole human blood, and the risk of induction of tolerance to fibrinolytic agents were investigated. A rat model of intravascular catheter infection was established to investigate the efficacy of selected fibrinolytic agents in vivo Under biomimetic conditions, the fibrinolytic agents effectively dispersed established S. aureus biofilms and, in combination with common antistaphylococcal antimicrobials, effectively killed bacterial cells being released from the biofilm. These fibrinolytic agents were not cytotoxic and did not affect the host immune response. The rat model of infection successfully demonstrated the activity of the selected fibrinolytic agents alone and in combination with antimicrobials on established biofilms in vivo TrypLE and nattokinase most successfully removed adherent cells from plasma-coated surfaces and significantly improved the efficacy of existing antimicrobials against S. aureus biofilms in vitro and in vivo These biofilm dispersal agents represent a viable future treatment option for S. aureus device-related infections. Copyright © 2018 American Society for Microbiology.

Jacob: An Educational Agent in a Virtual Environment

NARCIS (Netherlands)

van den Bosch, A.; Evers, M.J.; Nijholt, Antinus; Weigand, H.

2000-01-01

The Jacob Project involves the construction of a virtual environment where an animated human-like agent called Jacob gives instruction to the user. The project focuses on three issues: the software engineering aspects of building a virtual reality system, the integration of natural language

Potent antitumor bifunctional DNA alkylating agents, synthesis and biological activities of 3a-aza-cyclopenta[a]indenes.

Science.gov (United States)

Kakadiya, Rajesh; Dong, Huajin; Lee, Pei-Chih; Kapuriya, Naval; Zhang, Xiuguo; Chou, Ting-Chao; Lee, Te-Chang; Kapuriya, Kalpana; Shah, Anamik; Su, Tsann-Long

2009-08-01

A series of bifunctional DNA interstrand cross-linking agents, bis(hydroxymethyl)- and bis(carbamates)-8H-3a-azacyclopenta[a]indene-1-yl derivatives were synthesized for antitumor evaluation. The preliminary antitumor studies revealed that these agents exhibited potent cytotoxicity in vitro and antitumor therapeutic efficacy against human tumor xenografts in vivo. Furthermore, these derivatives have little or no cross-resistance to either Taxol or Vinblastine. Remarkably, complete tumor remission in nude mice bearing human breast carcinoma MX-1 xenograft by 13a,b and 14g,h and significant suppression against prostate adenocarcinoma PC3 xenograft by 13b were achieved at the maximum tolerable dose with relatively low toxicity. In addition, these agents induce DNA interstrand cross-linking and substantial G2/M phase arrest in human non-small lung carcinoma H1299 cells. The current studies suggested that these agents are promising candidates for preclinical studies.

Identification of novel human damage response proteins targeted through yeast orthology.

Directory of Open Access Journals (Sweden)

J Peter Svensson

Full Text Available Studies in Saccharomyces cerevisiae show that many proteins influence cellular survival upon exposure to DNA damaging agents. We hypothesized that human orthologs of these S. cerevisiae proteins would also be required for cellular survival after treatment with DNA damaging agents. For this purpose, human homologs of S. cerevisiae proteins were identified and mapped onto the human protein-protein interaction network. The resulting human network was highly modular and a series of selection rules were implemented to identify 45 candidates for human toxicity-modulating proteins. The corresponding transcripts were targeted by RNA interference in human cells. The cell lines with depleted target expression were challenged with three DNA damaging agents: the alkylating agents MMS and 4-NQO, and the oxidizing agent t-BuOOH. A comparison of the survival revealed that the majority (74% of proteins conferred either sensitivity or resistance. The identified human toxicity-modulating proteins represent a variety of biological functions: autophagy, chromatin modifications, RNA and protein metabolism, and telomere maintenance. Further studies revealed that MMS-induced autophagy increase the survival of cells treated with DNA damaging agents. In summary, we show that damage recovery proteins in humans can be identified through homology to S. cerevisiae and that many of the same pathways are represented among the toxicity modulators.

Deploying Affect-Inspired Mechanisms to Enhance Agent Decision-Making and Communication

OpenAIRE

Antos, Dimitrios

2012-01-01

Computer agents are required to make appropriate decisions quickly and efficiently. As the environments in which they act become increasingly complex, efficient decision-making becomes significantly more challenging. This thesis examines the positive ways in which human emotions influence people’s ability to make good decisions in complex, uncertain contexts, and develops computational analogues of these beneficial functions, demonstrating their usefulness in agent decision-making and communi...

Holograms as Teaching Agents

Science.gov (United States)

Walker, Robin A.

2013-02-01

Hungarian physicist Dennis Gabor won the Pulitzer Prize for his 1947 introduction of basic holographic principles, but it was not until the invention of the laser in 1960 that research scientists, physicians, technologists and the general public began to seriously consider the interdisciplinary potentiality of holography. Questions around whether and when Three-Dimensional (3-D) images and systems would impact American entertainment and the arts would be answered before educators, instructional designers and students would discover how much Three-Dimensional Hologram Technology (3DHT) would affect teaching practices and learning environments. In the following International Symposium on Display Holograms (ISDH) poster presentation, the author features a traditional board game as well as a reflection hologram to illustrate conventional and evolving Three-Dimensional representations and technology for education. Using elements from the American children's toy Operation® (Hasbro, 2005) as well as a reflection hologram of a human brain (Ko, 1998), this poster design highlights the pedagogical effects of 3-D images, games and systems on learning science. As teaching agents, holograms can be considered substitutes for real objects, (human beings, organs, and animated characters) as well as agents (pedagogical, avatars, reflective) in various learning environments using many systems (direct, emergent, augmented reality) and electronic tools (cellphones, computers, tablets, television). In order to understand the particular importance of utilizing holography in school, clinical and public settings, the author identifies advantages and benefits of using 3-D images and technology as instructional tools.

Recent advances in evaluation of oxime efficacy in nerve agent poisoning by in vitro analysis

International Nuclear Information System (INIS)

Worek, F.; Eyer, P.; Aurbek, N.; Szinicz, L.; Thiermann, H.

2007-01-01

The availability of highly toxic organophosphorus (OP) warfare agents (nerve agents) underlines the necessity for an effective medical treatment. Acute OP toxicity is primarily caused by inhibition of acetylcholinesterase (AChE). Reactivators (oximes) of inhibited AChE are a mainstay of treatment, however, the commercially available compounds, obidoxime and pralidoxime, are considered to be rather ineffective against various nerve agents, e.g. soman and cyclosarin. This led to the synthesis and investigation of numerous oximes in the past decades. Reactivation of OP-inhibited AChE is considered to be the most important reaction of oximes. Clinical data from studies with pesticide-poisoned patients support the assumption that the various reactions between AChE, OP and oxime, i.e. inhibition, reactivation and aging, can be investigated in vitro with human AChE. In contrast to animal experiments such in vitro studies with human tissue enable the evaluation of oxime efficacy without being affected by species differences. In the past few years numerous in vitro studies were performed by different groups with a large number of oximes and methods were developed for extrapolating in vitro data to different scenarios of human nerve agent poisoning. The present status in the evaluation of new oximes as antidotes against nerve agent poisoning will be discussed

Human Respiratory Syncytial Virus and Human Metapneumovirus

Directory of Open Access Journals (Sweden)

Luciana Helena Antoniassi da Silva

2009-08-01

Full Text Available The human respiratory syncytial virus (hRSV and the human metapneumovírus (hMPV are main etiological agents of acute respiratory infections (ARI. The ARI is an important cause of childhood morbidity and mortality worldwide.  hRSV and hMPV are members of the Paramyxoviridae. They are enveloped, non-segmented viruses, with negative-sense single stranded genomes. Respiratory syncytial virus (hRSV is the best characterized agent viral of this group, associated with respiratory diseases in lower respiratory tract. Recently, a new human pathogen belonging to the subfamily Pneumovirinae was identified, the human metapneumovirus (hMPV, which is structurally similar to the hRSV, in genomic organization, viral structure, antigenicity and clinical symptoms.  The subfamily Pneumovirinae contains two genera: genus Pneumovirus contains hRSV, the bovine (bRSV, as well as the ovine and caprine respiratory syncytial virus and pneumonia virus of mice, the second genus Metapneumovirus, consists of avian metapneumovirus (aMPV and human metapneumovirus (hMPV. In this work, we present a brief narrative review of the literature on important aspects of the biology, epidemiology and clinical manifestations of infections by two respiratory viruses.

Medical Surveillance Monthly Report (MSMR). Volume 16, Number 4, April 2009

Science.gov (United States)

2009-04-01

years, sexually-transmitted infections (due to chlamydia, gonorrhea , syphilis, and nongonococcal urethritis) accounted for most (n=17,535; 87.4%) of...3 3 2 5 1 Ehrlichiosis 0 2 2 3 2 Encephalitis 3 1 0 1 0 Filariasis 1 0 0 0 0 Giardiasis 37 35 16 23 43 Gonorrhea 1,977 1,821 1,818 1,872 2,126 H. infl...0 0 E. coli O157:H7 1 2 2 2 0 Ehrlichiosis 0 2 1 2 1 Encephalitis 0 0 0 0 0 Filariasis 1 0 0 0 0 Giardiasis 21 17 11 13 17 Gonorrhea 1,398 1,501

Dramatic Expression in Opera, and Its Implications for Conversational Agents

National Research Council Canada - National Science Library

Johnson, W. L

2003-01-01

It is commonly agreed among embodied conversational agent (ECA) researchers that ECA behavior should be based upon principles of human face-to-face communication (Cassell et al., 2000; Traum & Rickel, 2002...

Pathogenic agents in freshwater resources

Science.gov (United States)

Geldreich, Edwin E.

1996-02-01

Numerous pathogenic agents have been found in freshwaters used as sources for water supplies, recreational bathing and irrigation. These agents include bacterial pathogens, enteric viruses, several protozoans and parasitic worms more common to tropical waters. Although infected humans are a major source of pathogens, farm animals (cattle, sheep, pigs), animal pets (dogs, cats) and wildlife serve as significant reservoirs and should not be ignored. The range of infected individuals within a given warm-blooded animal group (humans included) may range from 1 to 25%. Survival times for pathogens in the water environment may range from a few days to as much as a year (Ascaris, Taenia eggs), with infective dose levels varying from one viable cell for several primary pathogenic agents to many thousands of cells for a given opportunistic pathogen.As pathogen detection in water is complex and not readily incorporated into routine monitoring, a surrogate is necessary. In general, indicators of faecal contamination provide a positive correlation with intestinal pathogen occurrences only when appropriate sample volumes are examined by sensitive methodology.Pathways by which pathogens reach susceptible water users include ingestion of contaminated water, body contact with polluted recreational waters and consumption of salad crops irrigated by polluted freshwaters. Major contributors to the spread of various water-borne pathogens are sewage, polluted surface waters and stormwater runoff. All of these contributions are intensified during periods of major floods. Several water-borne case histories are cited as examples of breakdowns in public health protection related to water supply, recreational waters and the consumption of contaminated salad crops. In the long term, water resource management must focus on pollution prevention from point sources of waste discharges and the spread of pathogens in watershed stormwater runoff.

[Alkylating agents].

Science.gov (United States)

Pourquier, Philippe

2011-11-01

With the approval of mechlorethamine by the FDA in 1949 for the treatment of hematologic malignancies, alkylating agents are the oldest class of anticancer agents. Even though their clinical use is far beyond the use of new targeted therapies, they still occupy a major place in specific indications and sometimes represent the unique option for the treatment of refractory diseases. Here, we are reviewing the major classes of alkylating agents and their mechanism of action, with a particular emphasis for the new generations of alkylating agents. As for most of the chemotherapeutic agents used in the clinic, these compounds are derived from natural sources. With a complex but original mechanism of action, they represent new interesting alternatives for the clinicians, especially for tumors that are resistant to conventional DNA damaging agents. We also briefly describe the different strategies that have been or are currently developed to potentiate the use of classical alkylating agents, especially the inhibition of pathways that are involved in the repair of DNA lesions induced by these agents. In this line, the development of PARP inhibitors is a striking example of the recent regain of interest towards the "old" alkylating agents.

“Toward socially responsible agents: integrating attachment and learning in emotional decision-making,”

OpenAIRE

M. Ben Moussa and N. Magnenat-Thalmann

2013-01-01

Our goal is to create socially responsible agents either robots or virtual humans. In this paper we present an integration of emotions attachment and learning in emotional decision making to achieve this goal. Based on emerging psychological theories we aim at building human like emotional decision making where emotions play a central role in selecting the next action to be performed by the agent. Here we present our own approach for emotion appraisal where we use emotional attachment as an i...

AFFECTIVE GUIDANCE OF INTELLIGENT AGENTS: How Emotion Controls Cognition1

Science.gov (United States)

Clore, Gerald L.; Palmer, Janet E.

2008-01-01

Emotions and moods color cognition. In this article, we outline how emotions affect judgments and cognitive performance of human agents. We argue that affective influences are due, not to the affective reactions themselves, but to the information they carry about value, a potentially useful finding for creators of artificial agents. The kind of influence that occurs depends on the focus of the agent at the time. When making evaluative judgments, for example, agents may experience positive affect as a positive attitude toward a person or object. But when an agent focuses on a cognitive task, positive affect may act like performance feedback, with positive affect giving a green light to cognitive, relational processes. By contrast, negative affect tends to inhibit relational processing, resulting in a more perceptual, stimulus-specific processing. One result is that many textbook phenomena from cognitive psychology occur readily in happy moods, but are inhibited in sad moods. PMID:19255620

An agent-based model of cellular dynamics and circadian variability in human endotoxemia.

Directory of Open Access Journals (Sweden)

Tung T Nguyen

Full Text Available As cellular variability and circadian rhythmicity play critical roles in immune and inflammatory responses, we present in this study an agent-based model of human endotoxemia to examine the interplay between circadian controls, cellular variability and stochastic dynamics of inflammatory cytokines. The model is qualitatively validated by its ability to reproduce circadian dynamics of inflammatory mediators and critical inflammatory responses after endotoxin administration in vivo. Novel computational concepts are proposed to characterize the cellular variability and synchronization of inflammatory cytokines in a population of heterogeneous leukocytes. Our results suggest that there is a decrease in cell-to-cell variability of inflammatory cytokines while their synchronization is increased after endotoxin challenge. Model parameters that are responsible for IκB production stimulated by NFκB activation and for the production of anti-inflammatory cytokines have large impacts on system behaviors. Additionally, examining time-dependent systemic responses revealed that the system is least vulnerable to endotoxin in the early morning and most vulnerable around midnight. Although much remains to be explored, proposed computational concepts and the model we have pioneered will provide important insights for future investigations and extensions, especially for single-cell studies to discover how cellular variability contributes to clinical implications.

EtpE Binding to DNase X Induces Ehrlichial Entry via CD147 and hnRNP-K Recruitment, Followed by Mobilization of N-WASP and Actin.

Science.gov (United States)

Mohan Kumar, Dipu; Lin, Mingqun; Xiong, Qingming; Webber, Mathew James; Kural, Comert; Rikihisa, Yasuko

2015-11-03

Obligate intracellular bacteria, such as Ehrlichia chaffeensis, perish unless they can enter eukaryotic cells. E. chaffeensis is the etiological agent of human monocytic ehrlichiosis, an emerging infectious disease. To infect cells, Ehrlichia uses the C terminus of the outer membrane invasin entry-triggering protein (EtpE) of Ehrlichia (EtpE-C), which directly binds the mammalian cell surface glycosylphosphatidyl inositol-anchored protein, DNase X. How this binding drives Ehrlichia entry is unknown. Here, using affinity pulldown of host cell lysates with recombinant EtpE-C (rEtpE-C), we identified two new human proteins that interact with EtpE-C: CD147 and heterogeneous nuclear ribonucleoprotein K (hnRNP-K). The interaction of CD147 with rEtpE-C was validated by far-Western blotting and coimmunoprecipitation of native EtpE with endogenous CD147. CD147 was ubiquitous on the cell surface and also present around foci of rEtpE-C-coated-bead entry. Functional neutralization of surface-exposed CD147 with a specific antibody inhibited Ehrlichia internalization and infection but not binding. Downregulation of CD147 by short hairpin RNA (shRNA) impaired E. chaffeensis infection. Functional ablation of cytoplasmic hnRNP-K by a nanoscale intracellular antibody markedly attenuated bacterial entry and infection but not binding. EtpE-C also interacted with neuronal Wiskott-Aldrich syndrome protein (N-WASP), which is activated by hnRNP-K. Wiskostatin, which inhibits N-WASP activation, and cytochalasin D, which inhibits actin polymerization, inhibited Ehrlichia entry. Upon incubation with host cell lysate, EtpE-C but not an EtpE N-terminal fragment stimulated in vitro actin polymerization in an N-WASP- and DNase X-dependent manner. Time-lapse video images revealed N-WASP recruitment at EtpE-C-coated bead entry foci. Thus, EtpE-C binding to DNase X drives Ehrlichia entry by engaging CD147 and hnRNP-K and activating N-WASP-dependent actin polymerization. Ehrlichia chaffeensis, an

Probiotics as Antiviral Agents in Shrimp Aquaculture

Directory of Open Access Journals (Sweden)

Bestha Lakshmi

2013-01-01

Full Text Available Shrimp farming is an aquaculture business for the cultivation of marine shrimps or prawns for human consumption and is now considered as a major economic and food production sector as it is an increasingly important source of protein available for human consumption. Intensification of shrimp farming had led to the development of a number of diseases, which resulted in the excessive use of antimicrobial agents, which is finally responsible for many adverse effects. Currently, probiotics are chosen as the best alternatives to these antimicrobial agents and they act as natural immune enhancers, which provoke the disease resistance in shrimp farm. Viral diseases stand as the major constraint causing an enormous loss in the production in shrimp farms. Probiotics besides being beneficial bacteria also possess antiviral activity. Exploitation of these probiotics in treatment and prevention of viral diseases in shrimp aquaculture is a novel and efficient method. This review discusses the benefits of probiotics and their criteria for selection in shrimp aquaculture and their role in immune power enhancement towards viral diseases.

Jacob - an animated instruction agent for virtual reality

NARCIS (Netherlands)

Evers, M.J.; Nijholt, Antinus; Tan, T.; Shi, Y.; Gao, W.

2000-01-01

This paper gives an overview of the Jacob project. This project in-volves the construction of a 3D virtual environment where an animated human-like agent called Jacob gives instruction to the user. The project investigates virtual reality techniques and focuses on three issues: the software

A Social Cognitive Neuroscience Stance on Human-Robot Interactions

Directory of Open Access Journals (Sweden)

Chaminade Thierry

2011-12-01

Full Text Available Robotic devices, thanks to the controlled variations in their appearance and behaviors, provide useful tools to test hypotheses pertaining to social interactions. These agents were used to investigate one theoretical framework, resonance, which is defined, at the behavioral and neural levels, as an overlap between first- and third- person representations of mental states such as motor intentions or emotions. Behaviorally, we found a reduced, but significant, resonance towards a humanoid robot displaying biological motion, compared to a human. Using neuroimaging, we've reported that while perceptual processes in the human occipital and temporal lobe are more strongly engaged when perceiving a humanoid robot than a human action, activity in areas involved in motor resonance depends on attentional modulation for artificial agent more strongly than for human agents. Altogether, these studies using artificial agents offer valuable insights into the interaction of bottom-up and top-down processes in the perception of artificial agents.

Characterization of nanoparticle-based contrast agents for molecular magnetic resonance imaging

International Nuclear Information System (INIS)

Shan, Liang; Chopra, Arvind; Leung, Kam; Eckelman, William C.; Menkens, Anne E.

2012-01-01

The development of molecular imaging agents is currently undergoing a dramatic expansion. As of October 2011, ∼4,800 newly developed agents have been synthesized and characterized in vitro and in animal models of human disease. Despite this rapid progress, the transfer of these agents to clinical practice is rather slow. To address this issue, the National Institutes of Health launched the Molecular Imaging and Contrast Agents Database (MICAD) in 2005 to provide freely accessible online information regarding molecular imaging probes and contrast agents for the imaging community. While compiling information regarding imaging agents published in peer-reviewed journals, the MICAD editors have observed that some important information regarding the characterization of a contrast agent is not consistently reported. This makes it difficult for investigators to evaluate and meta-analyze data generated from different studies of imaging agents, especially for the agents based on nanoparticles. This article is intended to serve as a guideline for new investigators for the characterization of preclinical studies performed with nanoparticle-based MRI contrast agents. The common characterization parameters are summarized into seven categories: contrast agent designation, physicochemical properties, magnetic properties, in vitro studies, animal studies, MRI studies, and toxicity. Although no single set of parameters is suitable to define the properties of the various types of contrast agents, it is essential to ensure that these agents meet certain quality control parameters at the preclinical stage, so that they can be used without delay for clinical studies.

Chemical analysis of wine conservation agents and their impact on health

Directory of Open Access Journals (Sweden)

Esipov A. S.

2017-12-01

Full Text Available the article provides the analysis of used conservation agents in the wine industry and the research about their impact on human's health. Sulfur dioxide and potassium sorbate are often used in the food industry and winery. This research shows which dose is potentially a threat to human's health. According to the norms of the Customs Union – the permissible dose of sulfites in wine is 300 mg/l. In this amount for healthy people, the E220 additive does not pose a threat. According to the research, the safest wines, with the minimum amount of conservation agents are "organic" wines, the content of sulfur dioxide in them is from 10 mg/l to 120 mg/l.

A strategy learning model for autonomous agents based on classification

Directory of Open Access Journals (Sweden)

Śnieżyński Bartłomiej

2015-09-01

Full Text Available In this paper we propose a strategy learning model for autonomous agents based on classification. In the literature, the most commonly used learning method in agent-based systems is reinforcement learning. In our opinion, classification can be considered a good alternative. This type of supervised learning can be used to generate a classifier that allows the agent to choose an appropriate action for execution. Experimental results show that this model can be successfully applied for strategy generation even if rewards are delayed. We compare the efficiency of the proposed model and reinforcement learning using the farmer-pest domain and configurations of various complexity. In complex environments, supervised learning can improve the performance of agents much faster that reinforcement learning. If an appropriate knowledge representation is used, the learned knowledge may be analyzed by humans, which allows tracking the learning process

Synergy of irofulven in combination with other DNA damaging agents: synergistic interaction with altretamine, alkylating, and platinum-derived agents in the MV522 lung tumor model.

Science.gov (United States)

Kelner, Michael J; McMorris, Trevor C; Rojas, Rafael J; Estes, Leita A; Suthipinijtham, Pharnuk

2008-12-01

Irofulven (MGI 114, NSC 683863) is a semisynthetic derivative of illudin S, a natural product present in the Omphalotus illudins (Jack O'Lantern) mushroom. This novel agent produces DNA damage, that in contrast to other agents, is predominately ignored by the global genome repair pathway of the nucleotide excision repair (NER)(2) system. The aim of this study was to determine the antitumor activity of irofulven when administered in combination with 44 different DNA damaging agents, whose damage is in general detected and repaired by the genome repair pathway. The human lung carcinoma MV522 cell line and its corresponding xenograft model were used to evaluate the activity of irofulven in combination with different DNA damaging agents. Two main classes of DNA damaging agents, platinum-derived agents, and select bifunctional alkylating agents, demonstrated in vivo synergistic or super-additive interaction with irofulven. DNA helicase inhibiting agents also demonstrated synergy in vitro, but an enhanced interaction with irofulven could not be demonstrated in vivo. There was no detectable synergistic activity between irofulven and agents capable of inducing DNA cleavage or intercalating into DNA. These results indicate that the antitumor activity of irofulven is enhanced when combined with platinum-derived agents, altretamine, and select alkylating agents such as melphalan or chlorambucil. A common factor between these agents appears to be the production of intrastrand DNA crosslinks. The synergistic interaction between irofulven and other agents may stem from the nucleotide excision repair system being selectively overwhelmed at two distinct points in the pathway, resulting in prolonged stalling of transcription forks, and subsequent initiation of apoptosis.

Human-Computer Interaction The Agency Perspective

CERN Document Server

Oliveira, José

2012-01-01

Agent-centric theories, approaches and technologies are contributing to enrich interactions between users and computers. This book aims at highlighting the influence of the agency perspective in Human-Computer Interaction through a careful selection of research contributions. Split into five sections; Users as Agents, Agents and Accessibility, Agents and Interactions, Agent-centric Paradigms and Approaches, and Collective Agents, the book covers a wealth of novel, original and fully updated material, offering:   ü  To provide a coherent, in depth, and timely material on the agency perspective in HCI ü  To offer an authoritative treatment of the subject matter presented by carefully selected authors ü  To offer a balanced and broad coverage of the subject area, including, human, organizational, social, as well as technological concerns. ü  To offer a hands-on-experience by covering representative case studies and offering essential design guidelines   The book will appeal to a broad audience of resea...

Bridging the gap between sample collection and laboratory analysis: using dried blood spots to identify human exposure to chemical agents

Science.gov (United States)

Hamelin, Elizabeth I.; Blake, Thomas A.; Perez, Jonas W.; Crow, Brian S.; Shaner, Rebecca L.; Coleman, Rebecca M.; Johnson, Rudolph C.

2016-05-01

Public health response to large scale chemical emergencies presents logistical challenges for sample collection, transport, and analysis. Diagnostic methods used to identify and determine exposure to chemical warfare agents, toxins, and poisons traditionally involve blood collection by phlebotomists, cold transport of biomedical samples, and costly sample preparation techniques. Use of dried blood spots, which consist of dried blood on an FDA-approved substrate, can increase analyte stability, decrease infection hazard for those handling samples, greatly reduce the cost of shipping/storing samples by removing the need for refrigeration and cold chain transportation, and be self-prepared by potentially exposed individuals using a simple finger prick and blood spot compatible paper. Our laboratory has developed clinical assays to detect human exposures to nerve agents through the analysis of specific protein adducts and metabolites, for which a simple extraction from a dried blood spot is sufficient for removing matrix interferents and attaining sensitivities on par with traditional sampling methods. The use of dried blood spots can bridge the gap between the laboratory and the field allowing for large scale sample collection with minimal impact on hospital resources while maintaining sensitivity, specificity, traceability, and quality requirements for both clinical and forensic applications.

Chemical warfare agents.

Science.gov (United States)

Kuca, Kamil; Pohanka, Miroslav

2010-01-01

Chemical warfare agents are compounds of different chemical structures. Simple molecules such as chlorine as well as complex structures such as ricin belong to this group. Nerve agents, vesicants, incapacitating agents, blood agents, lung-damaging agents, riot-control agents and several toxins are among chemical warfare agents. Although the use of these compounds is strictly prohibited, the possible misuse by terrorist groups is a reality nowadays. Owing to this fact, knowledge of the basic properties of these substances is of a high importance. This chapter briefly introduces the separate groups of chemical warfare agents together with their members and the potential therapy that should be applied in case someone is intoxicated by these agents.

Agent Model Development for Assessing Climate-Induced Geopolitical Instability.

Energy Technology Data Exchange (ETDEWEB)

Boslough, Mark B.; Backus, George A.

2005-12-01

We present the initial stages of development of new agent-based computational methods to generate and test hypotheses about linkages between environmental change and international instability. This report summarizes the first year's effort of an originally proposed three-year Laboratory Directed Research and Development (LDRD) project. The preliminary work focused on a set of simple agent-based models and benefited from lessons learned in previous related projects and case studies of human response to climate change and environmental scarcity. Our approach was to define a qualitative model using extremely simple cellular agent models akin to Lovelock's Daisyworld and Schelling's segregation model. Such models do not require significant computing resources, and users can modify behavior rules to gain insights. One of the difficulties in agent-based modeling is finding the right balance between model simplicity and real-world representation. Our approach was to keep agent behaviors as simple as possible during the development stage (described herein) and to ground them with a realistic geospatial Earth system model in subsequent years. This work is directed toward incorporating projected climate data--including various C02 scenarios from the Intergovernmental Panel on Climate Change (IPCC) Third Assessment Report--and ultimately toward coupling a useful agent-based model to a general circulation model.3

Logics for Intelligent Agents and Multi-Agent Systems

NARCIS (Netherlands)

Meyer, John-Jules Charles

2014-01-01

This chapter presents the history of the application of logic in a quite popular paradigm in contemporary computer science and artificial intelligence, viz. the area of intelligent agents and multi-agent systems. In particular we discuss the logics that have been used to specify single agents, the

The Role of Implicit Motives in Strategic Decision-Making: Computational Models of Motivated Learning and the Evolution of Motivated Agents

Directory of Open Access Journals (Sweden)

Kathryn Merrick

2015-11-01

Full Text Available Individual behavioral differences in humans have been linked to measurable differences in their mental activities, including differences in their implicit motives. In humans, individual differences in the strength of motives such as power, achievement and affiliation have been shown to have a significant impact on behavior in social dilemma games and during other kinds of strategic interactions. This paper presents agent-based computational models of power-, achievement- and affiliation-motivated individuals engaged in game-play. The first model captures learning by motivated agents during strategic interactions. The second model captures the evolution of a society of motivated agents. It is demonstrated that misperception, when it is a result of motivation, causes agents with different motives to play a given game differently. When motivated agents who misperceive a game are present in a population, higher explicit payoff can result for the population as a whole. The implications of these results are discussed, both for modeling human behavior and for designing artificial agents with certain salient behavioral characteristics.

An Agent-Based Dynamic Model of Politics, Fertility and Economic Development

Directory of Open Access Journals (Sweden)

Zining Yang

2016-08-01

Full Text Available In the political economy of development, government policy choices at a single point in time can dramatically affect a country's development path by impacting fertility, economic and political decisions across generations. Combining system dynamics and agent-based modeling approaches in a complex adaptive system, a simulation framework of the Politics of Fertility and Economic Development (POFED is formalized to understand the relationship between politics, economic, and demography change at both macro and micro levels. First, a new political capacity measurement is used; and the system dynamics model is validated with the latest data. Second, the endogenous attributes are fused with non-cooperative game theory in an agent-based framework to simulate the interactive political economic dynamics of individual intra-societal transactions. Finally, macro and micro levels are connected with policy levers of political capacity and political instability by merging system dynamics and agent-based components. This paper also explores the agent-based model's behavioral dynamics via simulation methods to identify paths towards economic development and political stability. This model demonstrates micro level human agency can act, react and interact, thus driving macro level dynamics, while macro structures provide political, social and economic environments that constrain or incentivize micro level human behavior.

Emerging Vector-Borne Diseases - Incidence through Vectors.

Science.gov (United States)

Savić, Sara; Vidić, Branka; Grgić, Zivoslav; Potkonjak, Aleksandar; Spasojevic, Ljubica

2014-01-01

Vector-borne diseases use to be a major public health concern only in tropical and subtropical areas, but today they are an emerging threat for the continental and developed countries also. Nowadays, in intercontinental countries, there is a struggle with emerging diseases, which have found their way to appear through vectors. Vector-borne zoonotic diseases occur when vectors, animal hosts, climate conditions, pathogens, and susceptible human population exist at the same time, at the same place. Global climate change is predicted to lead to an increase in vector-borne infectious diseases and disease outbreaks. It could affect the range and population of pathogens, host and vectors, transmission season, etc. Reliable surveillance for diseases that are most likely to emerge is required. Canine vector-borne diseases represent a complex group of diseases including anaplasmosis, babesiosis, bartonellosis, borreliosis, dirofilariosis, ehrlichiosis, and leishmaniosis. Some of these diseases cause serious clinical symptoms in dogs and some of them have a zoonotic potential with an effect to public health. It is expected from veterinarians in coordination with medical doctors to play a fundamental role at primarily prevention and then treatment of vector-borne diseases in dogs. The One Health concept has to be integrated into the struggle against emerging diseases. During a 4-year period, from 2009 to 2013, a total number of 551 dog samples were analyzed for vector-borne diseases (borreliosis, babesiosis, ehrlichiosis, anaplasmosis, dirofilariosis, and leishmaniasis) in routine laboratory work. The analysis was done by serological tests - ELISA for borreliosis, dirofilariosis, and leishmaniasis, modified Knott test for dirofilariosis, and blood smear for babesiosis, ehrlichiosis, and anaplasmosis. This number of samples represented 75% of total number of samples that were sent for analysis for different diseases in dogs. Annually, on average more then half of the samples

The Hybrid Ethical Reasoning Agent IMMANUEL

DEFF Research Database (Denmark)

Bentzen, Martin Mose; Linder, Felix

We introduce a novel software library that supportsthe implementation of hybrid ethical reasoning agents (HERA).The objective is to make moral principles available to robotprogramming. At its current stage, HERA can assess the moralpermissibility of actions using the principle of double effect......, andit can make utilitarian judgments.We present the prototype robotIMMANUEL based on HERA. The robot will be used to conductresearch on joint moral reasoning in human-robot interaction....

Biological Agents

Science.gov (United States)

... E-Tools Safety and Health Topics / Biological Agents Biological Agents This page requires that javascript be enabled ... 202) 693-2300 if additional assistance is required. Biological Agents Menu Overview In Focus: Ebola Frederick A. ...

The need for and development of behaviourally realistic agents

NARCIS (Netherlands)

Jager, W; Janssen, M; Sichman, JS; Bousquet, F; Davidsson, P

2003-01-01

In this paper we argue that simulating complex systems involving human behaviour requires agent rules based on a theoretically rooted structure that captures basic behavioural processes. Essential components of such a structure involve needs, decision-making processes and learning. Such a structure

Identifying candidate agents for lung adenocarcinoma by walking the human interactome

Directory of Open Access Journals (Sweden)

Sun Y

2016-09-01

Full Text Available Yajiao Sun,1 Ranran Zhang,2 Zhe Jiang,1 Rongyao Xia,1 Jingwen Zhang,1 Jing Liu,1 Fuhui Chen1 1Department of Respiratory, The Second Affiliated Hospital of Harbin Medical University, 2Department of Respiratory, Harbin First Hospital, Harbin, People’s Republic of China Abstract: Despite recent advances in therapeutic strategies for lung cancer, mortality is still increasing. Therefore, there is an urgent need to identify effective novel drugs. In the present study, we implement drug repositioning for lung adenocarcinoma (LUAD by a bioinformatics method followed by experimental validation. We first identified differentially expressed genes between LUAD tissues and nontumor tissues from RNA sequencing data obtained from The Cancer Genome Atlas database. Then, candidate small molecular drugs were ranked according to the effect of their targets on differentially expressed genes of LUAD by a random walk with restart algorithm in protein–protein interaction networks. Our method identified some potentially novel agents for LUAD besides those that had been previously reported (eg, hesperidin. Finally, we experimentally verified that atracurium, one of the potential agents, could induce A549 cells death in non-small-cell lung cancer-derived A549 cells by an MTT assay, acridine orange and ethidium bromide staining, and electron microscopy. Furthermore, Western blot assays demonstrated that atracurium upregulated the proapoptotic Bad and Bax proteins, downregulated the antiapoptotic p-Bad and Bcl-2 proteins, and enhanced caspase-3 activity. It could also reduce the expression of p53 and p21Cip1/Waf1 in A549 cells. In brief, the candidate agents identified by our approach may provide greater insights into improving the therapeutic status of LUAD. Keywords: lung adenocarcinoma, drug repositioning, bioinformatics, protein–protein interaction network, atracurium

A General Agent Model of Emotion and Trust using the BDI Structure

NARCIS (Netherlands)

Höhle, Daniel

2010-01-01

To endow virtual agents with more human-like behaviour, the current project proposes a new model for decision making based on emotions and trust. The project focuses first on the conceptual design of the model, then on the implementation of this model. To try to reproduce human decision making,

Suppression of NRF2–ARE activity sensitizes chemotherapeutic agent-induced cytotoxicity in human acute monocytic leukemia cells

Energy Technology Data Exchange (ETDEWEB)

Peng, Hui [The Hamner Institutes for Health Sciences, 6 Davis Drive, Research Triangle Park, NC (United States); Institute of Disease Control and Prevention, Academy of Military Medical Sciences, Beijing (China); Wang, Huihui [School of Public Health, China Medical University, 77 Puhe Road, Shenyang North New Area, Shenyang (China); Xue, Peng [The Hamner Institutes for Health Sciences, 6 Davis Drive, Research Triangle Park, NC (United States); Key Laboratory of the Public Health Safety, Ministry of Education, School of Public Health, Fudan University, Shanghai (China); Hou, Yongyong [School of Public Health, China Medical University, 77 Puhe Road, Shenyang North New Area, Shenyang (China); Dong, Jian [The Hamner Institutes for Health Sciences, 6 Davis Drive, Research Triangle Park, NC (United States); Institute of Biology and Medicine, Wuhan University of Science and Technology, Wuhan (China); Zhou, Tong [The Hamner Institutes for Health Sciences, 6 Davis Drive, Research Triangle Park, NC (United States); Qu, Weidong [Key Laboratory of the Public Health Safety, Ministry of Education, School of Public Health, Fudan University, Shanghai (China); Peng, Shuangqing [Institute of Disease Control and Prevention, Academy of Military Medical Sciences, Beijing (China); Li, Jin; Carmichael, Paul L. [Unilever, Safety & Environmental Assurance Centre, Colworth Science Park, Sharnbrook, Bedfordshire MK44 1LQ (United Kingdom); Nelson, Bud; Clewell, Rebecca; Zhang, Qiang; Andersen, Melvin E. [The Hamner Institutes for Health Sciences, 6 Davis Drive, Research Triangle Park, NC (United States); Pi, Jingbo, E-mail: jpi@mail.cmu.edu.cn [School of Public Health, China Medical University, 77 Puhe Road, Shenyang North New Area, Shenyang (China); The Hamner Institutes for Health Sciences, 6 Davis Drive, Research Triangle Park, NC (United States)

2016-02-01

Nuclear factor erythroid 2-related factor 2 (NRF2), a master regulator of the antioxidant response element (ARE)-dependent transcription, plays a pivotal role in chemical detoxification in normal and tumor cells. Consistent with previous findings that NRF2–ARE contributes to chemotherapeutic resistance of cancer cells, we found that stable knockdown of NRF2 by lentiviral shRNA in human acute monocytic leukemia (AML) THP-1 cells enhanced the cytotoxicity of several chemotherapeutic agents, including arsenic trioxide (As{sub 2}O{sub 3}), etoposide and doxorubicin. Using an ARE-luciferase reporter expressed in several human and mouse cells, we identified a set of compounds, including isonicotinic acid amides, isoniazid and ethionamide, that inhibited NRF2–ARE activity. Treatment of THP-1 cells with ethionamide, for instance, significantly reduced mRNA expression of multiple ARE-driven genes under either basal or As{sub 2}O{sub 3}-challenged conditions. As determined by cell viability and cell cycle, suppression of NRF2–ARE by ethionamide also significantly enhanced susceptibility of THP-1 and U937 cells to As{sub 2}O{sub 3}-induced cytotoxicity. In THP-1 cells, the sensitizing effect of ethionamide on As{sub 2}O{sub 3}-induced cytotoxicity was highly dependent on NRF2. To our knowledge, the present study is the first to demonstrate that ethionamide suppresses NRF2–ARE signaling and disrupts the transcriptional network of the antioxidant response in AML cells, leading to sensitization to chemotherapeutic agents. - Highlights: • Identification of novel inhibitors of ARE-dependent transcription • Suppression of NRF2–ARE sensitizes THP-1 cells to chemotherapy. • Ethionamide suppresses ARE-dependent transcriptional activity. • Ethionamide and isoniazid increase the cytotoxicity of As{sub 2}O{sub 3} in AML cells. • Sensitization of THP-1 cells to As{sub 2}O{sub 3} toxicity by ethionamide is NRF2-dependent.

Biologic Agents for Periodontal Regeneration and Implant Site Development

Directory of Open Access Journals (Sweden)

Fernando Suárez-López del Amo

2015-01-01

Full Text Available The advancement of molecular mediators or biologic agents has increased tremendously during the last decade in periodontology and dental implantology. Implant site development and reconstruction of the lost periodontium represent main fields in which these molecular mediators have been employed and investigated. Different growth factors trigger different reactions in the tissues of the periodontium at various cellular levels. Proliferation, migration, and differentiation constitute the main target areas of these molecular mediators. It was the purpose of this comprehensive review to describe the origin and rationale, evidence, and the most current understanding of the following biologic agents: Recombinant Human Platelet-Derived Growth Factor-BB (rhPDGF-BB, Enamel Matrix Derivate (EMD, Platelet-Rich Plasma (PRP and Platelet-Rich Fibrin (PRF, Recombinant Human Fibroblast Growth Factor-2 (rhFGF-2, Bone Morphogenic Proteins (BMPs, BMP-2 and BMP-7, Teriparatide PTH, and Growth Differential Factor-5 (GDF-5.

Self-interested agents create, maintain, and modify group-functional culture.

Science.gov (United States)

Singh, Manvir; Glowacki, Luke; Wrangham, Richard W

2016-01-01

We agree that institutions and rules are crucial for explaining human sociality, but we question the claim of there not being "alternatives to CGS [that] can easily account for the institutionalized cooperation that characterizes human societies" (target article, sect. 7). Hypothesizing that self-interested individuals coercively and collaboratively create rules, we propose that agent-based hypotheses offer viable alternatives to cultural group selection (CGS).

Synthesis of radiolabeled racemic and enanthiomeric antiarrhythmic agents

International Nuclear Information System (INIS)

Hsi, R.S.P.; Stolle, W.T.; Stelzer, L.S.; Hester, J.B.; Perricone, S.C.

1992-01-01

Ventricular fibrillation is a leading cause of fatality in patients suffering from cardiovascular disorders. Among approaches to treating cardiac dysrhythmia with medicinal agents is the use of compounds categorized as open-quotes Class IIIclose quotes antiarrhythmic agents to prolong cardiac action potential and increase the refractoriness of cardiac tissues without affecting the sodium current. Investigations into structural requirements necessary for such biological activities led to the synthesis of a series of aniline-propanolamine derivatives. This report describes the preparation of carbon-14 and tritium labeled forms of racemic and enantiomeric forms of these derivatives for conducting drug disposition studies in test animals and human subjects

Agentes estressores no trabalho e sugestões para amenizá-los: opiniões de enfermeiros de pós-graduação Stressors agents in workplace and sugestions to soften its: opinions of the post graduation's nurses

Directory of Open Access Journals (Sweden)

Luciana Monteiro Mendes Martins

2000-03-01

Full Text Available A sobrecarga de trabalho, relacionamento e comunicação, características da Instituição e poluição ambiental foram os agentes estressores organizacionais mais citados neste estudo composto por 30 enfermeiras, sendo que a melhoria no planejamento do trabalho, o aspecto de humanização, adequação dos recursos humanos, melhora na comunicação e educação continuada, dentre outras, foram as sugestões identificadas para melhorar estes agentes estressores. Como agentes estressores extra organizacionais, os mais citados foram problemas econômicos e familiares e distância do trabalho / transporte.The work overload, relationship and comunication problems, institution's characteristics and ambiental pollution were the stressing organization agents with the greatest pontuation in this study composed by 30 nurses. The work planning, work humanization, suitable human resourses, improving comunication and continued education were the suggestions given by nurses to minimize these stressing organizational agents. Analysing the stressing extra organizational agents, economic and familiar problems, work distance and transportation to work , were the most pointed.

Synthetic cannabimimetic agents metabolized by carboxylesterases

DEFF Research Database (Denmark)

Thomsen, Ragnar; Nielsen, Line M; Holm, Niels B

2015-01-01

Synthetic cannabimimetic agents are a large group of diverse compounds which act as agonists at cannabinoid receptors. Since 2004, synthetic cannabinoids have been used recreationally, although several of the compounds have been shown to cause severe toxicity in humans. In this study......, the metabolism of two indazole carboxamide derivatives, AB-PINACA and AB-FUBINACA, was investigated by using human liver microsomes (HLM). For both compounds, a major metabolic pathway was the enzymatic hydrolysis of the primary amide, resulting in the major metabolites AB-PINACA-COOH and AB-FUBINACA-COOH. Other...... major metabolic pathways were mono-hydroxylation of the N-pentyl chain in AB-PINACA and mono-hydroxylation of the 1-amino-3-methyl-1-oxobutane moiety in AB-FUBINACA. To identify the enzyme(s) responsible for the amide hydrolysis, incubations with recombinant carboxylesterases and human serum, as well...

Hybrid layer difference between sixth and seventh generation bonding agent

Directory of Open Access Journals (Sweden)

Grace Syavira Suryabrata

2006-03-01

Full Text Available Since etching is completed at the same stage as priming and bonding, when applying the sixth and seventh generation bonding, the exposed smear layers are constantly surrounded by primer and bonding and cannot collapse. The smear layer and the depth of penetration of resin bonding in dentinal tubules are completely integrated into hybrid layer. The purpose of this laboratory research was to study the penetration depth of two self etching adhesive. Fourteen samples of human extracted teeth were divided into two groups. Each groups consisted of seven samples, each of them was treated with sixth generation bonding agent and the other was treated with seventh generation bonding agent. The results disclosed that the penetration into dentinal tubules of seventh generation bonding agent was deeper than sixth generation bonding agent. Conclusion: bond strength will improve due to the increasing of penetration depth of resin bonding in dentinal tubules.

Theories about architecture and performance of multi-agent systems

NARCIS (Netherlands)

Gazendam, Henk W.M.; Jorna, René J.

1998-01-01

Multi-agent systems are promising as models of organization because they are based on the idea that most work in human organizations is done based on intelligence, communication, cooperation, and massive parallel processing. They offer an alternative for system theories of organization, which are

Should autonomous agents be liable for what they do?

NARCIS (Netherlands)

Hage, Jaap; Keirse, A.; Loos, M.

2017-01-01

This article argues that it may be useful to sometimes hold autonomous agents, and not only their users, responsible for their acts. In this connection autonomous systems can be computer programs that interact with the outside world without human interference, including ‘intelligent’ weapons and

Cognitive Agents in Virtual Worlds : a Middleware Design Approach

NARCIS (Netherlands)

van Oijen, Joost

2014-01-01

In the past decade, significant advances have been made in the technologies for creating virtual worlds. These advances are accompanied with the need for intelligent, human-like characters to populate these virtual worlds. Such characters are also known as intelligent virtual agents (IVAs). IVAs are

Robots As Intentional Agents: Using Neuroscientific Methods to Make Robots Appear More Social

Science.gov (United States)

Wiese, Eva; Metta, Giorgio; Wykowska, Agnieszka

2017-01-01

Robots are increasingly envisaged as our future cohabitants. However, while considerable progress has been made in recent years in terms of their technological realization, the ability of robots to interact with humans in an intuitive and social way is still quite limited. An important challenge for social robotics is to determine how to design robots that can perceive the user’s needs, feelings, and intentions, and adapt to users over a broad range of cognitive abilities. It is conceivable that if robots were able to adequately demonstrate these skills, humans would eventually accept them as social companions. We argue that the best way to achieve this is using a systematic experimental approach based on behavioral and physiological neuroscience methods such as motion/eye-tracking, electroencephalography, or functional near-infrared spectroscopy embedded in interactive human–robot paradigms. This approach requires understanding how humans interact with each other, how they perform tasks together and how they develop feelings of social connection over time, and using these insights to formulate design principles that make social robots attuned to the workings of the human brain. In this review, we put forward the argument that the likelihood of artificial agents being perceived as social companions can be increased by designing them in a way that they are perceived as intentional agents that activate areas in the human brain involved in social-cognitive processing. We first review literature related to social-cognitive processes and mechanisms involved in human–human interactions, and highlight the importance of perceiving others as intentional agents to activate these social brain areas. We then discuss how attribution of intentionality can positively affect human–robot interaction by (a) fostering feelings of social connection, empathy and prosociality, and by (b) enhancing performance on joint human–robot tasks. Lastly, we describe circumstances under

Robots As Intentional Agents: Using Neuroscientific Methods to Make Robots Appear More Social

Directory of Open Access Journals (Sweden)

Eva Wiese

2017-10-01

Full Text Available Robots are increasingly envisaged as our future cohabitants. However, while considerable progress has been made in recent years in terms of their technological realization, the ability of robots to interact with humans in an intuitive and social way is still quite limited. An important challenge for social robotics is to determine how to design robots that can perceive the user’s needs, feelings, and intentions, and adapt to users over a broad range of cognitive abilities. It is conceivable that if robots were able to adequately demonstrate these skills, humans would eventually accept them as social companions. We argue that the best way to achieve this is using a systematic experimental approach based on behavioral and physiological neuroscience methods such as motion/eye-tracking, electroencephalography, or functional near-infrared spectroscopy embedded in interactive human–robot paradigms. This approach requires understanding how humans interact with each other, how they perform tasks together and how they develop feelings of social connection over time, and using these insights to formulate design principles that make social robots attuned to the workings of the human brain. In this review, we put forward the argument that the likelihood of artificial agents being perceived as social companions can be increased by designing them in a way that they are perceived as intentional agents that activate areas in the human brain involved in social-cognitive processing. We first review literature related to social-cognitive processes and mechanisms involved in human–human interactions, and highlight the importance of perceiving others as intentional agents to activate these social brain areas. We then discuss how attribution of intentionality can positively affect human–robot interaction by (a fostering feelings of social connection, empathy and prosociality, and by (b enhancing performance on joint human–robot tasks. Lastly, we describe

Behavior believability in virtual worlds: agents acting when they need to.

Science.gov (United States)

Avradinis, Nikos; Panayiotopoulos, Themis; Anastassakis, George

2013-12-01

Believability has been a perennial goal for the intelligent virtual agent community. One important aspect of believability largely consists in demonstrating autonomous behavior, consistent with the agent's personality and motivational state, as well as the world conditions. Autonomy, on behalf of the agent, implies the existence of an internal structure and mechanism that allows the agent to have its own needs and interests, based on which the agent will dynamically select and generate goals that will in turn lead to self-determined behavior. Intrinsic motivation allows the agent to function and demonstrate behavior, even when no external stimulus is present, due to the constant change of its internal emotional and physiological state. The concept of motivation has already been investigated by research works on intelligent agents, trying to achieve autonomy. The current work presents an architecture and model to represent and manage internal driving factors in intelligent virtual agents, using the concept of motivations. Based on Maslow and Alderfer's bio-psychological needs theories, we present a motivational approach to represent human needs and produce emergent behavior through motivation synthesis. Particular attention is given to basic, physiological level needs, which are the basis of behavior and can produce tendency to action even when there is no other interaction with the environment.

Biochemical changes in pancytopenic and non pancytopenic dogs with ehrlichiosis/ Alterações bioquímicas em cães citopênicos e não citopênicos com ehrlichiose

Directory of Open Access Journals (Sweden)

Cecília Braga Laposy

2008-08-01

Full Text Available In order to study the biochemical changes in naturally infected dogs with Ehrlichia canis, blood samples from 57 animals were collected. Thirty-five healthy dogs were used as control group. Dosage of serum protein, albumin, globulin, albumin:globulin ratio (A:G, urea, creatinine, alanine aminotransferase (ALT e alkaline phosphatase (AP were carried out. The comparison of mean in infected and control group as well as the distribution of frequencies were investigated in order to associate the disease to the findings. Hypoproteinemia, hypoalbuminemia, decreased A:G ratio, hyperglobulinemia, and uremia were associated to ehrlichiosis (p Com o objetivo de estudar os parâmetros bioquímicos associados às funções renal e hepática em cães naturalmente infectados por Ehrlichia canis e associá-los à ehrlichiose, foram colhidas 57 amostras de sangue, com realização de dosagem de proteína plasmática total, albumina, globulina, relação albumina/ globulina (A/G, uréia, creatinina, alanino aminotransferase (ALT e fosfatase alcalina (FA. Outros 35 cães em higidez foram utilizados como controle. Foram comparadas as médias dos animais infectados e controle, bem como a distribuição de freqüências, para associação dos resultados com a doença. Hipoproteinemia, hipoalbuminemia, redução da A/G, hiperglobulinemia e aumento de uréia estiveram associados à doença (p < 0,05. Foram comparados também os achados entre animais não pancitopênicos (NPan e em pancitopenia (Pan, verificando-se que no primeiro grupo, houve aumento de ALT, e nos animais pancitopênicos, a creatinina foi o principal indicador de ehrlichiose. No caso do perfil protéico, não houve diferença que pudesse servir como marcador da fase da enfermidade nos animais infectados.

Framework for Securing Mobile Software Agents

OpenAIRE

Mwakalinga, G Jeffy; Yngström, Louise

2006-01-01

Information systems are growing in size and complexity making it infeasible for human administrators to manage them. The aim of this work is to study ways of securing and using mobile software agents to deter attackers, protect information systems, detect intrusions, automatically respond to the intrusions and attacks, and to produce recovery services to systems after attacks. Current systems provide intrusion detection, prevention, protection, response, and recovery services but most of thes...

Topographic assessment of human enamel surface treated with different topical sodium fluoride agents: Scanning electron microscope consideration

Directory of Open Access Journals (Sweden)

Gurlal Singh Brar

2017-01-01

Full Text Available Introduction: Continuous balanced demineralization and remineralization are natural dynamic processes in enamel. If the balance is interrupted and demineralization process dominates, it may eventually lead to the development of carious lesions in enamel and dentine. Fluoride helps control decay by enhancing remineralization and altering the structure of the tooth, making the surface less soluble. Methodology: One hundred and twenty sound human permanent incisors randomly and equally distributed into six groups as follows: Group I - Control, II - Sodium fluoride solution, III - Sodium fluoride gel, IV - Sodium fluoride varnish, V - Clinpro Tooth Crème (3M ESPE, and VI-GC Tooth Mousse Plus or MI Paste Plus. The samples were kept in artificial saliva for 12 months, and the topical fluoride agents were applied to the respective sample groups as per the manufacturer instructions. Scanning electron microscope (SEM evaluation of all the samples after 6 and 12 months was made. Results: Morphological changes on the enamel surface after application of fluoride in SEM revealed the presence of globular precipitate in all treated samples. Amorphous, globular, and crystalline structures were seen on the enamel surface of the treated samples. Clear differences were observed between the treated and untreated samples. Conclusion: Globular structures consisting of amorphous CaF2precipitates, which acted as a fluoride reservoir, were observed on the enamel surface after action of different sodium fluoride agents. CPP-ACPF (Tooth Mousse and Tricalcium phosphate with fluoride (Clinpro tooth crème are excellent delivery vehicles available in a slow release amorphous form to localize fluoride at the tooth surface.

Molecular identification and polymorphism determination of cutaneous and visceral leishmaniasis agents isolated from human and animal hosts in Iran.

Science.gov (United States)

Hajjaran, Homa; Mohebali, Mehdi; Mamishi, Setareh; Vasigheh, Farzaneh; Oshaghi, Mohammad Ali; Naddaf, Saied Reza; Teimouri, Aref; Edrissian, Gholam Hossein; Zarei, Zabiholah

2013-01-01

Amplification of internal transcript spacer 1 of ribosomal RNA (ITS1-RNA) gene followed by RFLP analysis and sequencing was used to identify the causing agents of cutaneous and visceral leishmaniasis (CL and VL) in humans and animal reservoir hosts from various geographical areas in Iran. We also used random amplified polymorphic DNA (RAPD-PCR) to obtain polymorphisms among isolates of Leishmania spp. Totally, 362 suspected human and animal cases including 173 CL, 49 VL, 60 rodents, and 80 domestic dogs were examined for Leishmania infection. From 112 culture-positive samples prepared from CL cases, 75 (67%) were infected with L. major and 37 (33%) with L. tropica. Of the 60 rodents examined, 25 (41.6%) harbored the Leishmania infection; 21 were infected with L. major and 4 with L. turanica. From 49 suspected VL, 29 were positive by direct agglutination test (DAT), whereas microscopy detected parasite in bone marrow of 25 and culture in 28 of the patients. Two VL patients were infected with L. tropica and 26 with L. infantum. Of the 80 domestic dogs, 56 showed anti-Leishmania antibodies with DAT. Of these, 55 were positive by both microscopy and culture. Molecular identity, obtained only for 47 samples, revealed L. infantum in 43 and L. tropica in 4 dogs. The polymorphisms among L. tropica and L. major isolates were 3.6% and 7.3%; the rate among human and canine VL isolates was 2.8% and 9.8%, respectively. Our results showed that at least four different Leishmania species with various polymorphisms circulate among humans and animal hosts in Iran.

Non-verbal Persuasion and Communication in an Affective Agent

DEFF Research Database (Denmark)

André, Elisabeth; Bevacqua, Elisabetta; Heylen, Dirk

2011-01-01

the critical role of non-verbal behaviour during face-to-face communication. In this chapter we restrict the discussion to body language. We also consider embodied virtual agents. As is the case with humans, there are a number of fundamental factors to be considered when constructing persuasive agents......This chapter deals with the communication of persuasion. Only a small percentage of communication involves words: as the old saying goes, “it’s not what you say, it’s how you say it”. While this likely underestimates the importance of good verbal persuasion techniques, it is accurate in underlining...

Development of (F-18)-Labeled Amyloid Imaging Agents for PET

International Nuclear Information System (INIS)

Mathis, C.A.

2007-01-01

The applicant proposes to design and synthesize a series of fluorine-18-labeled radiopharmaceuticals to be used as amyloid imaging agents for positron emission tomography (PET). The investigators will conduct comprehensive iterative in vitro and in vivo studies based upon well defined acceptance criteria in order to identify lead agents suitable for human studies. The long term goals are to apply the selected radiotracers as potential diagnostic agents of Alzheimer's disease (AD), as surrogate markers of amyloid in the brain to determine the efficacy of anti-amyloid therapeutic drugs, and as tools to help address basic scientific questions regarding the progression of the neuropathology of AD, such as testing the 'amyloid cascade hypothesis' which holds that amyloid accumulation is the primary cause of AD.

An Integrated Human System Interaction (HSI) Framework for Human-Agent Team Collaboration, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — The NASA commitment to a human presence in space exploration results in the interaction of humans with challenging environments in space, on lunar, and on planetary...

The effect of calcium phosphate-containing desensitizing agent on ...

African Journals Online (AJOL)

Objective: The aim of this study was to investigate the effect of calcium phosphate containing desensitizing pretreatments on the microtensile bond strength (MTBS) and microleakage of the multimode adhesive agent to dentin. Materials and Methods: In this study, twelve noncarious, freshly extracted human third molar teeth ...

FRIEND: a brain-monitoring agent for adaptive and assistive systems.

Science.gov (United States)

Morris, Alexis; Ulieru, Mihaela

2012-01-01

This paper presents an architectural design for adaptive-systems agents (FRIEND) that use brain state information to make more effective decisions on behalf of a user; measuring brain context versus situational demands. These systems could be useful for alerting users to cognitive workload levels or fatigue, and could attempt to compensate for higher cognitive activity by filtering noise information. In some cases such systems could also share control of devices, such as pulling over in an automated vehicle. These aim to assist people in everyday systems to perform tasks better and be more aware of internal states. Achieving a functioning system of this sort is a challenge, involving a unification of brain- computer-interfaces, human-computer-interaction, soft-computin deliberative multi-agent systems disciplines. Until recently, these were not able to be combined into a usable platform due largely to technological limitations (e.g., size, cost, and processing speed), insufficient research on extracting behavioral states from EEG signals, and lack of low-cost wireless sensing headsets. We aim to surpass these limitations and develop control architectures for making sense of brain state in applications by realizing an agent architecture for adaptive (human-aware) technology. In this paper we present an early, high-level design towards implementing a multi-purpose brain-monitoring agent system to improve user quality of life through the assistive applications of psycho-physiological monitoring, noise-filtering, and shared system control.

Contrast agents for cardiac angiography: effects of a nonionic agent vs. a standard ionic agent

International Nuclear Information System (INIS)

Bettmann, M.A.; Bourdillon, P.D.; Barry, W.H.; Brush, K.A.; Levin, D.C.

1984-01-01

The effects on cardiac hemodynamics and of a standard contrast agent, sodium methylglucamine diatrizoate [Renografin 76] were compared with the effects of a new nonionic agent (iohexol) in a double-blind study in 51 patietns undergoing coronary angiography and left ventriculography. No significant alteration in measured blood parameters occurred with either contrast agent. Hemodynamic changes occurred with both, but were significantly greater with the standard renografin than with the low-osmolality, nonionic iohexol. After left ventriculography, heart rate increased and peripheral arterial pressure fell with both agents, but less with iohexol. It is concluded that iohexol causes less alteration in cardiac function than does the agent currently most widely used. Nonionic contrast material is likely to improve the safety of coronary angiography, particularly in those patients at greatest risk

From actors to agents in socio-ecological systems models.

Science.gov (United States)

Rounsevell, M D A; Robinson, D T; Murray-Rust, D

2012-01-19

The ecosystem service concept has emphasized the role of people within socio-ecological systems (SESs). In this paper, we review and discuss alternative ways of representing people, their behaviour and decision-making processes in SES models using an agent-based modelling (ABM) approach. We also explore how ABM can be empirically grounded using information from social survey. The capacity for ABM to be generalized beyond case studies represents a crucial next step in modelling SESs, although this comes with considerable intellectual challenges. We propose the notion of human functional types, as an analogy of plant functional types, to support the expansion (scaling) of ABM to larger areas. The expansion of scope also implies the need to represent institutional agents in SES models in order to account for alternative governance structures and policy feedbacks. Further development in the coupling of human-environment systems would contribute considerably to better application and use of the ecosystem service concept.

Human migraine models

DEFF Research Database (Denmark)

Iversen, Helle Klingenberg

2001-01-01

, which is a human experience. A set-up for investigations of experimental headache and migraine in humans, has been evaluated and headache mechanisms explored by using nitroglycerin and other headache-inducing agents. Nitric oxide (NO) or other parts of the NO activated cascade seems to be responsible...

Diagnostic agents containing albumin and methods for making same

International Nuclear Information System (INIS)

Saklad, E.L.; Layne, W.W.

1981-01-01

This patent specification outlines a method for providing a diagnostic agent for use in radiological testing, comprising the production of an admixture of a source of radionuclide ion (sup(99m)Tc), a reducing agent (source of stannous ions at a pH below 7) and a stabilized, defatted human albumin being sufficiently purified for an aqueous solution not to become cloudy for at least an hour at a pH of 4 or below. Other aspects of the patent provide for a method of producing a radiodiagnostic kit of the above components, packaged in a sealed sterile non-pyrogenic container, and also a method of concentrating sup(99m)Tc in vivo in a target mammalian tissue, by intravenous administration of a mixture of sup(99m)Tc, a reducing agent, and delipidized serum albumin. (U.K.)

Modelling Engagement in Multi-Party Conversations : Data-Driven Approaches to Understanding Human-Human Communication Patterns for Use in Human-Robot Interactions

OpenAIRE

Oertel, Catharine

2016-01-01

The aim of this thesis is to study human-human interaction in order to provide virtual agents and robots with the capability to engage into multi-party-conversations in a human-like-manner. The focus lies with the modelling of conversational dynamics and the appropriate realization of multi-modal feedback behaviour. For such an undertaking, it is important to understand how human-human communication unfolds in varying contexts and constellations over time. To this end, multi-modal human-human...

Information Security for Compliance with Select Agent Regulations

Science.gov (United States)

Lewis, Nick; Campbell, Mark J.

2015-01-01

The past decade has seen a significant rise in research on high-consequence human and animal pathogens, many now known as “select agents.” While physical security around these agents is tightly regulated, information security standards are still lagging. The understanding of the threats unique to the academic and research environment is still evolving, in part due to poor communication between the various stakeholders. Perhaps as a result, information security guidelines published by select agent regulators lack the critical details and directives needed to achieve even the lowest security level of the Federal Information Security Management Act (FISMA). While only government agencies are currently required to abide by the provisions of FISMA (unless specified as preconditions for obtaining government grants or contracts—still a relatively rare or narrowly scoped occurrence), the same strategies were recently recommended by executive order for others. We propose that information security guidelines for select agent research be updated to promulgate and detail FISMA standards and processes and that the latter be ultimately incorporated into select agent regulations. We also suggest that information security in academic and research institutions would greatly benefit from active efforts to improve communication among the biosecurity, security, and information technology communities, and from a secure venue for exchange of timely information on emerging threats and solutions in the research environment. PMID:26042864

Information security for compliance with select agent regulations.

Science.gov (United States)

Lewis, Nick; Campbell, Mark J; Baskin, Carole R

2015-01-01

The past decade has seen a significant rise in research on high-consequence human and animal pathogens, many now known as "select agents." While physical security around these agents is tightly regulated, information security standards are still lagging. The understanding of the threats unique to the academic and research environment is still evolving, in part due to poor communication between the various stakeholders. Perhaps as a result, information security guidelines published by select agent regulators lack the critical details and directives needed to achieve even the lowest security level of the Federal Information Security Management Act (FISMA). While only government agencies are currently required to abide by the provisions of FISMA (unless specified as preconditions for obtaining government grants or contracts--still a relatively rare or narrowly scoped occurrence), the same strategies were recently recommended by executive order for others. We propose that information security guidelines for select agent research be updated to promulgate and detail FISMA standards and processes and that the latter be ultimately incorporated into select agent regulations. We also suggest that information security in academic and research institutions would greatly benefit from active efforts to improve communication among the biosecurity, security, and information technology communities, and from a secure venue for exchange of timely information on emerging threats and solutions in the research environment.

Impact of Human like Cues on Human Trust in Machines: Brain Imaging and Modeling Studies for Human-Machine Interactions

Science.gov (United States)

2018-01-05

opponent had some human-likeness. In particular, the research shows that activity in the left parietal region correlating with a human players future ...human-likeness. In particular, our research shows that activity in the left parietal region correlating with a human player’s future behavior can be...this work. - Emotional Conversational Agent: The 4th Korean Flagship AI Project, from December 2016 to December 2020, about US$14,000,000 (Principal

Pulp tissue response to Portland cement associated with different radio pacifying agents on pulpotomy of human primary molars.

Science.gov (United States)

Marques, N; Lourenço Neto, N; Fernandes, A P; Rodini, C; Hungaro Duarte, M; Rios, D; Machado, M A; Oliveira, T

2015-12-01

The objective of this research was to evaluate the response of Portland cement associated with different radio pacifying agents on pulp treatment of human primary teeth by clinical and radiographic exams and microscopic analysis. Thirty mandibular primary molars were randomly divided into the following groups: Group I - Portland cement; Group II - Portland cement with iodoform (Portland cement + CHI3 ); Group III - Portland cement with zirconium oxide (Portland cement + ZrO2 ); and treated by pulpotomy technique (removal of a portion of the pulp aiming to maintain the vitally of the remaining radicular pulp tissue using a therapeutic dressing). Clinical and radiographic evaluations were recorded at 6, 12 and 24 months follow-up. The teeth at the regular exfoliation period were extracted and processed for histological analysis. Data were tested using statistical analysis with a significance level of 5%. The microscopic findings were descriptively analysed. All treated teeth were clinically and radiographically successful at follow-up appointments. The microscopic analysis revealed positive response to pulp repair with hard tissue barrier formation and pulp calcification in the remaining roots of all available teeth. The findings of this study suggest that primary teeth pulp tissue exhibited satisfactory biological response to Portland cement associated with radio pacifying agents. However, further studies with long-term follow-up are needed to determine the safe clinical indication of this alternative material for pulp therapy of primary teeth. © 2015 The Authors Journal of Microscopy © 2015 Royal Microscopical Society.

A few bad apples: a model of disease influenced agent behaviour in a heterogeneous contact environment.

Directory of Open Access Journals (Sweden)

Jessica Enright

Full Text Available For diseases that infect humans or livestock, transmission dynamics are at least partially dependent on human activity and therefore human behaviour. However, the impact of human behaviour on disease transmission is relatively understudied, especially in the context of heterogeneous contact structures such as described by a social network. Here, we use a strategic game, coupled with a simple disease model, to investigate how strategic agent choices impact the spread of disease over a contact network. Using beliefs that are based on disease status and that build up over time, agents choose actions that stochastically determine disease spread on the network. An agent's disease status is therefore a function of both his own and his neighbours actions. The effect of disease on agents is modelled by a heterogeneous payoff structure. We find that the combination of network shape and distribution of payoffs has a non-trivial impact on disease prevalence, even if the mean payoff remains the same. An important scenario occurs when a small percentage (called noncooperators have little incentive to avoid disease. For diseases that are easily acquired when taking a risk, then even when good behavior can lead to disease eradication, a small increase in the percentage of noncooperators (less than 5% can yield a large (up to 25% increase in prevalence.

The clinical use of contrast agents in magnetic resonance imaging

International Nuclear Information System (INIS)

Bydder, G.M.

1987-01-01

Interest in the use of external agents to increase tissue contrasts has come from many sources dating back to the earliest work in NMR, to animal studies and to the widespread use of contrast agents in conventional radiological practice. The first clinical magnetic resonance images were published in 1980 and in the following year a brief account of the use of the paramagnetic agents in human volunteers was established. It was apparent relatively early in the development of magnetic resonance imaging (MRI) that a high level of soft tissue contrast was available de novo and the need for externally administered agents might therefore be small. This observation was tempered by the fact that separation of tumour from oedema was frequently better with contrast enhanced CT X-ray than with unenhanced MRI and that of a contrast agent might therefore be needed for MRI. At the end of 1983 the first parenteral agent gadoliminum diethylene triamine pentaacetic acid (Gd-DTPA) was used in volunteers and clinical studies began in 1984. At the present time only molecular O/sub 2/, oral iron compounds and Gd-DTPA are in clinical use although there are a number of other agents which have been used in animals and some of these may become available for clinical use in the foreseeable future

Resistance to organophosphorus agent toxicity in transgenic mice expressing the G117H mutant of human butyrylcholinesterase

International Nuclear Information System (INIS)

Wang Yuxia; Ticu Boeck, Andreea; Duysen, Ellen G.; Van Keuren, Margaret; Saunders, Thomas L.; Lockridge, Oksana

2004-01-01

Organophosphorus toxicants (OP) include chemical nerve agents and pesticides. The goal of this work was to find out whether an animal could be made resistant to OP toxicity by genetic engineering. The human butyrylcholinesterase (BChE) mutant G117H was chosen for study because it has the unusual ability to hydrolyze OP as well as acetylcholine, and it is resistant to inhibition by OP. Human G117H BChE, under the control of the ROSA26 promoter, was expressed in all tissues of transgenic mice. A stable transgenic mouse line expressed 0.5 μg/ml of human G117H BChE in plasma as well as 2 μg/ml of wild-type mouse BChE. Intestine, kidneys, stomach, lungs, heart, spleen, liver, brain, and muscle expressed 0.6-0.15 μg/g of G117H BChE. Transgenic mice were normal in behavior and fertility. The LD50 dose of echothiophate for wild-type mice was 0.1 mg/kg sc. This dose caused severe cholinergic signs of toxicity and lethality in wild-type mice, but caused no deaths and only mild toxicity in transgenic animals. The mechanism of protection was investigated by measuring acetylcholinesterase (AChE) and BChE activity. It was found that AChE and endogenous BChE were inhibited to the same extent in echothiophate-treated wild type and transgenic mice. This led to the hypothesis that protection against echothiophate toxicity was not explained by hydrolysis of echothiophate. In conclusion, the transgenic G117H BChE mouse demonstrates the factors required to achieve protection from OP toxicity in a vertebrate animal

Development of Class IIa Bacteriocins as Therapeutic Agents

Directory of Open Access Journals (Sweden)

Christopher T. Lohans

2012-01-01

Full Text Available Class IIa bacteriocins have been primarily explored as natural food preservatives, but there is much interest in exploring the application of these peptides as therapeutic antimicrobial agents. Bacteriocins of this class possess antimicrobial activity against several important human pathogens. Therefore, the therapeutic development of these bacteriocins will be reviewed. Biological and chemical modifications to both stabilize and increase the potency of bacteriocins are discussed, as well as the optimization of their production and purification. The suitability of bacteriocins as pharmaceuticals is explored through determinations of cytotoxicity, effects on the natural microbiota, and in vivo efficacy in mouse models. Recent results suggest that class IIa bacteriocins show promise as a class of therapeutic agents.

Social Importance Dynamics: A Model for Culturally-Adaptive Agents

NARCIS (Netherlands)

Mascarenhas, S.; Prada, R.; Paiva, A.; Hofstede, G.J.

2013-01-01

The unwritten rules of human cultures greatly affect social behaviour and as such should be considered in the development of socially intelligent agents. So far, there has been a large focus on modeling cultural aspects related to non-verbal behaviour such as gaze or body posture. However, culture

Simulation based on intelligent agents of the process of negotiation of the electric power market in Colombia

International Nuclear Information System (INIS)

Pastrana David, Maria Marcela; Guzman Luna, Jaime A; Ovalle Carranza, Demetrio Arturo

2005-01-01

The aim of this paper is describing the phases of analyzing, designing, building and validation of a multi-agent system to simulate the negotiation process of Colombian electric energy market. This project intent to exhibit advantages of multi-agent systems to model simulation processes. Analysis and design phases use MAS-common KADS rnethodology, which is one of the well known for agent-based system modeling. For this purpose, it is modeled the part of negotiation process among market human agents, which is representing by energy buying and selling among energy generators, commercial agents, and consumers

A Composite Agent Architecture for Multi-Agent Simulations

OpenAIRE

VanPutte, Michael; Osborn, Brian; Hiles, John

2002-01-01

CGF Computer Generated Forces and Behavioral Representation The MOVES Institute’s Computer-Generated Autonomy Group has focused on a research goal of modeling complex and adaptive behavior while at the same time making the behavior easier to create and control. This research has led to several techniques for agent construction, that includes a social and organization relationship management engine, a composite agent architecture, an agent goal apparatus, a structure for capturi...

Computer Agent's Role in Modeling an Online Math Help User

OpenAIRE

Dragana Martinovic

2007-01-01

This paper investigates perspectives of deployments of open learner model on mathematics online help sites. It proposes enhancing a regular human-to-human interaction with an involvement of a computer agent suitable for tracking users, checking their input and making useful suggestions. Such a design would provide the most support for the interlocutors while keeping the nature of existing environment intact. Special considerations are given to peer-to-peer and expert-to-student mathematics on...

Allelopathic potential of some biocontrol agents for the control of ...

African Journals Online (AJOL)

The adverse effect of synthetic pesticides on human health and the natural ecosystem necessitate the need to explore natural mechanisms of disease control in plants. This study evaluated the allelopathic potential of five biocontrol agents: Trichoderma longibrachiatum, Trichoderma asperellum, Bacillus subtilis, Bacillus ...

Fuzzy Cognitive and Social Negotiation Agent Strategy for Computational Collective Intelligence

Science.gov (United States)

Chohra, Amine; Madani, Kurosh; Kanzari, Dalel

Finding the adequate (win-win solutions for both parties) negotiation strategy with incomplete information for autonomous agents, even in one-to-one negotiation, is a complex problem. Elsewhere, negotiation behaviors, in which the characters such as conciliatory or aggressive define a 'psychological' aspect of the negotiator personality, play an important role. The aim of this paper is to develop a fuzzy cognitive and social negotiation strategy for autonomous agents with incomplete information, where the characters conciliatory, neutral, or aggressive, are suggested to be integrated in negotiation behaviors (inspired from research works aiming to analyze human behavior and those on social negotiation psychology). For this purpose, first, one-to-one bargaining process, in which a buyer agent and a seller agent negotiate over single issue (price), is developed for a time-dependent strategy (based on time-dependent behaviors of Faratin et al.) and for a fuzzy cognitive and social strategy. Second, experimental environments and measures, allowing a set of experiments, carried out for different negotiation deadlines of buyer and seller agents, are detailed. Third, experimental results for both time-dependent and fuzzy cognitive and social strategies are presented, analyzed, and compared for different deadlines of agents. The suggested fuzzy cognitive and social strategy allows agents to improve the negotiation process, with regard to the time-dependent one, in terms of agent utilities, round number to reach an agreement, and percentage of agreements.

Autonomy in robots and other agents.

Science.gov (United States)

Smithers, T

1997-06-01

The word "autonomous" has become widely used in artificial intelligence, robotics, and, more recently, artificial life and is typically used to qualify types of systems, agents, or robots: we see terms like "autonomous systems," "autonomous agents," and "autonomous robots." Its use in these fields is, however, both weak, with no distinctions being made that are not better and more precisely made with other existing terms, and varied, with no single underlying concept being involved. This ill-disciplined usage contrasts strongly with the use of the same term in other fields such as biology, philosophy, ethics, law, and human rights, for example. In all these quite different areas the concept of autonomy is essentially the same, though the language used and the aspects and issues of concern, of course, differ. In all these cases the underlying notion is one of self-law making and the closely related concept of self-identity. In this paper I argue that the loose and varied use of the term autonomous in artificial intelligence, robotics, and artificial life has effectively robbed these fields of an important concept. A concept essentially the same as we find it in biology, philosophy, ethics, and law, and one that is needed to distinguish a particular kind of agent or robot from those developed and built so far. I suggest that robots and other agents will have to be autonomous, i.e., self-law making, not just self-regulating, if they are to be able effectively to deal with the kinds of environments in which we live and work: environments which have significant large scale spatial and temporal invariant structure, but which also have large amounts of local spatial and temporal dynamic variation and unpredictability, and which lead to the frequent occurrence of previously unexperienced situations for the agents that interact with them.

AgPi: Agents on Raspberry Pi

Directory of Open Access Journals (Sweden)

Tushar Semwal

2016-10-01

Full Text Available The Raspberry Pi and its variants have brought with them an aura of change in the world of embedded systems. With their impressive computation and communication capabilities and low footprint, these devices have thrown open the possibility of realizing a network of things in a very cost-effective manner. While such networks offer good solutions to prominent issues, they are indeed a long way from being smart or intelligent. Most of the currently available implementations of such a network of devices involve a centralized cloud-based server that contributes to making the necessary intelligent decisions, leaving these devices fairly underutilized. Though this paradigm provides for an easy and rapid solution, they have limited scalability, are less robust and at times prove to be expensive. In this paper, we introduce the concept of Agents on Raspberry Pi (AgPi as a cyber solution to enhance the smartness and flexibility of such embedded networks of physical devices in a decentralized manner. The use of a Multi-Agent System (MAS running on Raspberry Pis aids agents, both static and mobile, to govern the various activities within the network. Agents can act autonomously or on behalf of a human user and can collaborate, learn, adapt and act, thus contributing to embedded intelligence. This paper describes how Tartarus, a multi-agent platform, embedded on Raspberry Pis that constitute a network, can bring the best out of the system. To reveal the versatility of the concept of AgPi, an application for a Location-Aware and Tracking Service (LATS is presented. The results obtained from a comparison of data transfer cost between the conventional cloud-based approach with AgPi have also been included.

A Specific Inhibitor of TGF-β Receptor Kinase, SB-431542, as a Potent Antitumor Agent for Human Cancers

Directory of Open Access Journals (Sweden)

Sunil K. Halder

2005-05-01

Full Text Available Small molecule inhibitors of signaling pathways have proven to be extremely useful for the development of therapeutic strategies for human cancers. Blocking the tumor-promoting effects of transforming growth factor-β (TGF-β in advanced stage carcinogenesis provides a potentially interesting drug target for therapeutic intervention. Although very few TGF-β receptor kinase inhibitors (TRKI are now emerging in preclinical studies, nothing is known about how these inhibitors might regulate the tumor-suppressive or tumor-promoting effects of TGF-β, or when these inhibitors might be useful for treatment during cancer progression. We have investigated the potential of TRKI in new therapeutic approaches in preclinical models. Here, we demonstrate that the TRKI, SB-431542, inhibits TGF-β-induced transcription, gene expression, apoptosis, and growth suppression. We have observed that SB-431542 attenuates the tumor-promoting effects of TGF-β, including TGF-β-induced EMT, cell motility, migration and invasion, and vascular endothelial growth factor secretion in human cancer cell lines. Interestingly, SB-431542 induces anchorage independent growth of cells that are growth-inhibited by TGF-β, whereas it reduces colony formation by cells that are growth-promoted by TGF-β. However, SB-431542 has no effect on a cell line that failed to respond to TGF-β. This represents a novel potential application of these inhibitors as therapeutic agents for human cancers with the goal of blocking tumor invasion, angiogenesis, and metastasis, when tumors are refractory to TGF-β-induced tumor-suppressor functions but responsive to tumor-promoting effects of TGF-β.

Infants distinguish antisocial actions directed towards fair and unfair agents.

Directory of Open Access Journals (Sweden)

Marek Meristo

Full Text Available Three experiments provide evidence of an incipient sense of fairness in preverbal infants. Ten-month-old infants were shown cartoon videos with two agents, the 'donors', who distributed resources to two identical recipients. One donor always distributed the goods equally, while the other performed unequal distributions by giving everything to one recipient. In the test phase, a third agent hit or took resources away from either the fair or the unfair donor. We found that infants looked longer when the antisocial actions were directed towards the unfair rather than the fair donor. These findings support the view that infants are able to evaluate agents based on their distributive actions and suggest that the foundations of human socio-moral competence are acquired independently of parental feedback and linguistic experience.

Inhibitory effects of antimicrobial agents against Fusarium species.

Science.gov (United States)

Kawakami, Hideaki; Inuzuka, Hiroko; Hori, Nobuhide; Takahashi, Nobumichi; Ishida, Kyoko; Mochizuki, Kiyofumi; Ohkusu, Kiyofumi; Muraosa, Yasunori; Watanabe, Akira; Kamei, Katsuhiko

2015-08-01

We investigated the inhibitory effects of antibacterial, biocidal, and antifungal agents against Fusarium spp. Seven Fusarium spp: four F. falciforme (Fusarium solani species complex), one Fusarium spp, one Fusarium spp. (Fusarium incarnatum-equiseti species complex), and one F. napiforme (Gibberella fujikuroi species complex), isolated from eyes with fungal keratitis were used in this study. Their susceptibility to antibacterial agents: flomoxef, imipenem, gatifloxacin, levofloxacin, moxifloxacin, gentamicin, tobramycin, and Tobracin® (contained 3,000 μg/ml of tobramycin and 25 μg/ml of benzalkonium chloride (BAK), a biocidal agent: BAK, and antifungal agents: amphotericin B, pimaricin (natamycin), fluconazole, itraconazole, miconazole, voriconazole, and micafungin, was determined by broth microdilution tests. The half-maximal inhibitory concentration (IC50), 100% inhibitory concentration (IC100), and minimum inhibitory concentration (MIC) against the Fusarium isolates were determined. BAK had the highest activity against the Fusarium spp. except for the antifungal agents. Three fluoroquinolones and two aminoglycosides had inhibitory effects against the Fusarium spp. at relatively high concentrations. Tobracin® had a higher inhibitory effect against Fusarium spp. than tobramycin alone. Amphotericin B had the highest inhibitory effect against the Fusarium spp, although it had different degrees of activity against each isolate. Our findings showed that fluoroquinolones, aminoglycosides, and BAK had some degree of inhibitory effect against the seven Fusarium isolates, although these agents had considerably lower effect than amphotericin B. However, the inhibitory effects of amphotericin B against the Fusarium spp. varied for the different isolates. Further studies for more effective medications against Fusarium, such as different combinations of antibacterial, biocidal, and antifungal agents are needed. © The Author 2015. Published by Oxford University Press on

Semi-Cooperative Learning in Smart Grid Agents

Science.gov (United States)

2013-12-01

this PhD program , but watching you grow has only made me realize how much more awesome human learning is. You have been a source of profound joy and...which should alleviate concern for scala - bility along this dimension. • Learning the negotiation model: Figure 6.23 shows single-episode results that...for Semi-cooperative Multi-agent Coordination. In IEEE Symposium on Adaptive Dynamic Programming and Reinforcement Learning . [Prendergast, 1999

Marine Algae as a Potential Source for Anti-Obesity Agents

Directory of Open Access Journals (Sweden)

Chu Wan-Loy

2016-12-01

Full Text Available Obesity is a major epidemic that poses a worldwide threat to human health, as it is also associated with metabolic syndrome, type 2 diabetes and cardiovascular disease. Therapeutic intervention through weight loss drugs, accompanied by diet and exercise, is one of the options for the treatment and management of obesity. However, the only approved anti-obesity drug currently available in the market is orlistat, a synthetic inhibitor of pancreatic lipase. Other anti-obesity drugs are still being evaluated at different stages of clinical trials, while some have been withdrawn due to their severe adverse effects. Thus, there is a need to look for new anti-obesity agents, especially from biological sources. Marine algae, especially seaweeds are a promising source of anti-obesity agents. Four major bioactive compounds from seaweeds which have the potential as anti-obesity agents are fucoxanthin, alginates, fucoidans and phlorotannins. The anti-obesity effects of such compounds are due to several mechanisms, which include the inhibition of lipid absorption and metabolism (e.g., fucoxanthin and fucoidans, effect on satiety feeling (e.g., alginates, and inhibition of adipocyte differentiation (e.g., fucoxanthin. Further studies, especially testing bioactive compounds in long-term human trials are required before any new anti-obesity drugs based on algal products can be developed.

Molecular Identification and Polymorphism Determination of Cutaneous and Visceral Leishmaniasis Agents Isolated from Human and Animal Hosts in Iran

Directory of Open Access Journals (Sweden)

Homa Hajjaran

2013-01-01

Full Text Available Amplification of internal transcript spacer 1 of ribosomal RNA (ITS1-RNA gene followed by RFLP analysis and sequencing was used to identify the causing agents of cutaneous and visceral leishmaniasis (CL and VL in humans and animal reservoir hosts from various geographical areas in Iran. We also used random amplified polymorphic DNA (RAPD-PCR to obtain polymorphisms among isolates of Leishmania spp. Totally, 362 suspected human and animal cases including 173 CL, 49 VL, 60 rodents, and 80 domestic dogs were examined for Leishmania infection. From 112 culture-positive samples prepared from CL cases, 75 (67% were infected with L. major and 37 (33% with L. tropica. Of the 60 rodents examined, 25 (41.6% harbored the Leishmania infection; 21 were infected with L. major and 4 with L. turanica. From 49 suspected VL, 29 were positive by direct agglutination test (DAT, whereas microscopy detected parasite in bone marrow of 25 and culture in 28 of the patients. Two VL patients were infected with L. tropica and 26 with L. infantum. Of the 80 domestic dogs, 56 showed anti-Leishmania antibodies with DAT. Of these, 55 were positive by both microscopy and culture. Molecular identity, obtained only for 47 samples, revealed L. infantum in 43 and L. tropica in 4 dogs. The polymorphisms among L. tropica and L. major isolates were 3.6% and 7.3%; the rate among human and canine VL isolates was 2.8% and 9.8%, respectively. Our results showed that at least four different Leishmania species with various polymorphisms circulate among humans and animal hosts in Iran.

Exploration of alternative test methods to evaluate phototoxicity of ophthalmic agents by using Statens Seruminstitut Rabbit Cornea cell lines and 3D human reconstituted cornea models.

Directory of Open Access Journals (Sweden)

Soyoung Kim

Full Text Available Many chemicals have been reported to induce phototoxicity. The absorbance of light energy within the sunlight range is a common characteristic of phototoxicity. The 3T3 NRU phototoxicity test (PT in 3T3 mouse skin fibroblasts has been used to identify the phototoxic potential induced by excited chemicals after exposure to ultra violet (UV. However, as phototoxicity may occur in ocular cells, it is necessary to develop a more suitable test for cornea-derived cells. In this study, we attempted to establish a new in vitro PT method in rabbit corneal cell lines (SIRC. We evaluated five ophthalmic agents, ciprofloxacin, levofloxacin, lomefloxacin, norfloxacin, and tetracycline, for their cytotoxic potential and in vitro phototoxicity. The results obtained using 3D human corneal models revealed that the UV-induced eye tissue toxicity by the test substances showed good correlation with those obtained using the in vitro phototoxicity test. However, the results from the 3D PT for ciprofloxacin, norfloxacin, and tetracycline in the 3D human cornea model were only partially comparable. Therefore, we suggest the SIRC cell line as a new phototoxicity test model; however, a sequential testing strategy, such as 3D PT, was also proposed to obtain relevant information for topical eye agents.

Polydisulfide Manganese(II) Complexes as Non-Gadolinium Biodegradable Macromolecular MRI Contrast Agents

Science.gov (United States)

Ye, Zhen; Jeong, Eun-Kee; Wu, Xueming; Tan, Mingqian; Yin, Shouyu; Lu, Zheng-Rong

2011-01-01

Purpose To develop safe and effective manganese(II) based biodegradable macromolecular MRI contrast agents. Materials and Methods In this study, we synthesized and characterized two polydisulfide manganese(II) complexes, Mn-DTPA cystamine copolymers and Mn-EDTA cystamine copolymers, as new biodegradable macromolecular MRI contrast agents. The contrast enhancement of the two manganese based contrast agents were evaluated in mice bearing MDA-MB-231 human breast carcinoma xenografts, in comparison with MnCl2. Results The T1 and T2 relaxivities were 4.74 and 10.38 mM−1s−1 per manganese at 3T for Mn-DTPA cystamine copolymers (Mn=30.50 kDa) and 6.41 and 9.72 mM−1s−1 for Mn-EDTA cystamine copolymers (Mn= 61.80 kDa). Both polydisulfide Mn(II) complexes showed significant liver, myocardium and tumor enhancement. Conclusion The manganese based polydisulfide contrast agents have a potential to be developed as alternative non-gadolinium contrast agents for MR cancer and myocardium imaging. PMID:22031457

Multi-Agent Pathfinding with n Agents on Graphs with n Vertices

DEFF Research Database (Denmark)

Förster, Klaus-Tycho; Groner, Linus; Hoefler, Torsten

2017-01-01

We investigate the multi-agent pathfinding (MAPF) problem with $n$ agents on graphs with $n$ vertices: Each agent has a unique start and goal vertex, with the objective of moving all agents in parallel movements to their goal s.t.~each vertex and each edge may only be used by one agent at a time....... We give a combinatorial classification of all graphs where this problem is solvable in general, including cases where the solvability depends on the initial agent placement. Furthermore, we present an algorithm solving the MAPF problem in our setting, requiring O(n²) rounds, or O(n³) moves...... of individual agents. Complementing these results, we show that there are graphs where Omega(n²) rounds and Omega(n³) moves are required for any algorithm....

Agent-specific learning signals for self-other distinction during mentalising.

Directory of Open Access Journals (Sweden)

Sam Ereira

2018-04-01

Full Text Available Humans have a remarkable ability to simulate the minds of others. How the brain distinguishes between mental states attributed to self and mental states attributed to someone else is unknown. Here, we investigated how fundamental neural learning signals are selectively attributed to different agents. Specifically, we asked whether learning signals are encoded in agent-specific neural patterns or whether a self-other distinction depends on encoding agent identity separately from this learning signal. To examine this, we tasked subjects to learn continuously 2 models of the same environment, such that one was selectively attributed to self and the other was selectively attributed to another agent. Combining computational modelling with magnetoencephalography (MEG enabled us to track neural representations of prediction errors (PEs and beliefs attributed to self, and of simulated PEs and beliefs attributed to another agent. We found that the representational pattern of a PE reliably predicts the identity of the agent to whom the signal is attributed, consistent with a neural self-other distinction implemented via agent-specific learning signals. Strikingly, subjects exhibiting a weaker neural self-other distinction also had a reduced behavioural capacity for self-other distinction and displayed more marked subclinical psychopathological traits. The neural self-other distinction was also modulated by social context, evidenced in a significantly reduced decoding of agent identity in a nonsocial control task. Thus, we show that self-other distinction is realised through an encoding of agent identity intrinsic to fundamental learning signals. The observation that the fidelity of this encoding predicts psychopathological traits is of interest as a potential neurocomputational psychiatric biomarker.

Agent Based Modelling for Social Simulation

OpenAIRE

Smit, S.K.; Ubink, E.M.; Vecht, B. van der; Langley, D.J.

2013-01-01

This document is the result of an exploratory project looking into the status of, and opportunities for Agent Based Modelling (ABM) at TNO. The project focussed on ABM applications containing social interactions and human factors, which we termed ABM for social simulation (ABM4SS). During the course of this project two workshops were organized. At these workshops, a wide range of experts, both ABM experts and domain experts, worked on several potential applications of ABM. The results and ins...

Macromolecular Antiviral Agents against Zika, Ebola, SARS, and Other Pathogenic Viruses

DEFF Research Database (Denmark)

Schandock, Franziska; Riber, Camilla Frich; Röcker, Annika

2017-01-01

. This work performs selection of synthetic polymers as novel broadly active agents and demonstrates activity of these polymers against Zika, Ebola, Lassa, Lyssa, Rabies, Marburg, Ebola, influenza, herpes simplex, and human immunodeficiency viruses. Results presented herein offer structure...

Intelligent Virtual Agents : 9th International Conference, IVA 2009 Amsterdam, The Netherlands, September 14-16, 2009 Proceedings

NARCIS (Netherlands)

Ruttkay, Z.M.; Kipp, M.; Nijholt, Antinus; Vilhjalmsson, H.H.

2009-01-01

Welcome to the Proceedings of the 9th International Conference on Intelligent Virtual Agents, held 14-16 September, 2009 in Amsterdam, The Netherlands. Intelligent Virtual Agents (IVAs) are interactive characters that exhibit humanlike qualities and communicate with humans or with each other using

9th KES Conference on Agent and Multi-Agent Systems : Technologies and Applications

CERN Document Server

Howlett, Robert; Jain, Lakhmi

2015-01-01

Agents and multi-agent systems are related to a modern software paradigm which has long been recognized as a promising technology for constructing autonomous, complex and intelligent systems. The topics covered in this volume include agent-oriented software engineering, agent co-operation, co-ordination, negotiation, organization and communication, distributed problem solving, specification of agent communication languages, agent privacy, safety and security, formalization of ontologies and conversational agents. The volume highlights new trends and challenges in agent and multi-agent research and includes 38 papers classified in the following specific topics: learning paradigms, agent-based modeling and simulation, business model innovation and disruptive technologies, anthropic-oriented computing, serious games and business intelligence, design and implementation of intelligent agents and multi-agent systems, digital economy, and advances in networked virtual enterprises. Published p...

Decentralized control of multi-agent aerial transportation system

KAUST Repository

Toumi, Noureddine

2017-04-01

Autonomous aerial transportation has multiple potential applications including emergency cases and rescue missions where ground intervention may be difficult. In this context, the following work will address the control of multi-agent Vertical Take-off and Landing aircraft (VTOL) transportation system. We develop a decentralized method. The advantage of such a solution is that it can provide better maneuverability and lifting capabilities compared to existing systems. First, we consider a cooperative group of VTOLs transporting one payload. The main idea is that each agent perceive the interaction with other agents as a disturbance while assuming a negotiated motion model and imposing certain magnitude bounds on each agent. The theoretical model will be then validated using a numerical simulation illustrating the interesting features of the presented control method. Results show that under specified disturbances, the algorithm is able to guarantee the tracking with a minimal error. We describe a toolbox that has been developed for this purpose. Then, a system of multiple VTOLs lifting payloads will be studied. The algorithm assures that the VTOLs are coordinated with minimal communication. Additionally, a novel gripper design for ferrous objects is presented that enables the transportation of ferrous objects without a cable. Finally, we discuss potential connections to human in the loop transportation systems.

The risk of some veterinary antimicrobial agents on public health associated with antimicrobial resistance and their molecular basis

OpenAIRE

Haihong Hao; Zahid Iqbal; Yulian Wang; Guyue Cheng; Zong-Hui Yuan

2016-01-01

The risk of antimicrobial agents used in food-producing animals on public health associated with antimicrobial resistance continues to be a current topic of discussion as related to animal and human public health. In the present review, resistance monitoring data and risk assessment result of some important antimicrobial agents were cited to elucidate the possible association of antimicrobial use in food animals and antimicrobial resistance in human. From the selected examples, it was obvious...

Estimated general population control limits for unitary agents in drinking water, milk, soil, and unprocessed food items

Energy Technology Data Exchange (ETDEWEB)

Watson, A.P.; Adams, J.D.; Cerar, R.J.; Hess, T.L.; Kistner, S.L.; Leffingwell, S.S.; MacIntosh, R.G.; Ward, J.R.

1992-01-01

In the event of an unplanned release of chemical agent during any stage of the Chemical Stockpile Disposal Program (CSDP), the potential exists for contamination of drinking water, forage crops, grains, garden produce, and livestock. Persistent agents such as VX or sulfur mustard pose the greatest human health concern for reentry. This White Paper has been prepared to provide technical bases for these decisions by developing working estimates of agent control limits in selected environmental media considered principal sources of potential human exposure. To date, control limits for public exposure to unitary agents have been established for atmospheric concentrations only. The current analysis builds on previous work to calculate working estimates of control limits for ingestion and dermal exposure to potentially contaminated drinking water, milk, soil, and unprocessed food items such as garden produce. Information characterizing agent desorption from, and detection on or in, contaminated porous media are presently too developed to permit reasonable estimation of dermal exposure from this source. Thus, dermal contact with potentially contaminated porous surfaces is not considered in this document.

10th International Conference on Practical Applications of Agents and Multi-Agent Systems

CERN Document Server

Pérez, Javier; Golinska, Paulina; Giroux, Sylvain; Corchuelo, Rafael; Trends in Practical Applications of Agents and Multiagent Systems

2012-01-01

PAAMS, the International Conference on Practical Applications of Agents and Multi-Agent Systems is an evolution of the International Workshop on Practical Applications of Agents and Multi-Agent Systems. PAAMS is an international yearly tribune to present, to discuss, and to disseminate the latest developments and the most important outcomes related to real-world applications. It provides a unique opportunity to bring multi-disciplinary experts, academics and practitioners together to exchange their experience in the development of Agents and Multi-Agent Systems.   This volume presents the papers that have been accepted for the 2012 in the workshops: Workshop on Agents for Ambient Assisted Living, Workshop on Agent-Based Solutions for Manufacturing and Supply Chain and Workshop on Agents and Multi-agent systems for Enterprise Integration.

Trend of research and development on clearance system for CBRNE agents

International Nuclear Information System (INIS)

Ishihara, Masayuki; Fujita, Masanori; Ishida, Natsuko; Hattori, Hidemi; Tachibana, Shoich; Nakamura, Shingo; Kanatani, Yasuhiro

2013-01-01

In a field of disaster for a wide variety of Chemical, Biological, Radiological, Nuclear, Explosive (CBRNE) agents which are harmful and deadly poisonous, it is crucial to effectively clear those agents for prevention of expanded damages and retrieval from damage. The clearance technologies in the CBRNE disaster field require to be safe for human body and to be friendly for the environments. In addition, they need scientific data-based evidences for their effectiveness and safety. The aim of this article is to view the trend of research on clearances of N, B and c agents in terms of rapidity, simplicity and economic rationality, and to deliberate on effective clearance system using adequate equipments and materials for detoxification, decomposition and removal of each contamination. (author)

Riot Control Agents

Science.gov (United States)

... Submit What's this? Submit Button Facts About Riot Control Agents Interim document Recommend on Facebook Tweet Share Compartir What riot control agents are Riot control agents (sometimes referred to ...

Preparation and mechanism analysis of an environment-friendly maize seed coating agent.

Science.gov (United States)

Zeng, Defang; Fan, Zhao; Tian, Xu; Wang, Wenjin; Zhou, Mingchun; Li, Haochuan

2018-06-01

Traditional seed coating agents often contain toxic ingredients, which contaminate the environment and threaten human health. This paper expounds a method of preparing a novel environment-friendly seed coating agent for maize and researches its mechanism of action. The natural polysaccharide polymer, which is the main active ingredient of this environment-friendly seed coating agent, has the characteristics of innocuity and harmlessness, and it can replace the toxic ingredients used in traditional seed coating agents. This environment-friendly seed coating agent for maize was mainly made up of the natural polysaccharide polymer and other additives. The field trials results showed that the control efficacy of Helminthosporium maydis came to 93.72%, the anti-feeding rate of cutworms came to 81.29%, and the maize yield was increased by 17.75%. Besides, the LD 50 value (half the lethal dose in rats) of this seed coating agent was 10 times higher than that of the traditional seed coating agents. This seed coating agent could improve the activity of plant protective enzymes (peroxidase, catalase and superoxidase dismutase) and increase the chlorophyll content. This seed coating agent has four characteristics of disease prevention, desinsectization, increasing yield and safety. Results of mechanism analyses showed that this seed coating agent could enhance disease control effectiveness by improving plant protective enzymes activity and increase maize yield by improving chlorophyll content. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Constructing Secure Mobile Agent Systems Using the Agent Operating System

NARCIS (Netherlands)

van t Noordende, G.J.; Overeinder, B.J.; Timmer, R.J.; Brazier, F.M.; Tanenbaum, A.S.

2009-01-01

Designing a secure and reliable mobile agent system is a difficult task. The agent operating system (AOS) is a building block that simplifies this task. AOS provides common primitives required by most mobile agent middleware systems, such as primitives for secure communication, secure and

Nondestructive Intervention to Multi-Agent Systems through an Intelligent Agent

Science.gov (United States)

Han, Jing; Wang, Lin

2013-01-01

For a given multi-agent system where the local interaction rule of the existing agents can not be re-designed, one way to intervene the collective behavior of the system is to add one or a few special agents into the group which are still treated as normal agents by the existing ones. We study how to lead a Vicsek-like flocking model to reach synchronization by adding special agents. A popular method is to add some simple leaders (fixed-headings agents). However, we add one intelligent agent, called ‘shill’, which uses online feedback information of the group to decide the shill's moving direction at each step. A novel strategy for the shill to coordinate the group is proposed. It is strictly proved that a shill with this strategy and a limited speed can synchronize every agent in the group. The computer simulations show the effectiveness of this strategy in different scenarios, including different group sizes, shill speed, and with or without noise. Compared to the method of adding some fixed-heading leaders, our method can guarantee synchronization for any initial configuration in the deterministic scenario and improve the synchronization level significantly in low density groups, or model with noise. This suggests the advantage and power of feedback information in intervention of collective behavior. PMID:23658695

Nondestructive intervention to multi-agent systems through an intelligent agent.

Directory of Open Access Journals (Sweden)

Jing Han

Full Text Available For a given multi-agent system where the local interaction rule of the existing agents can not be re-designed, one way to intervene the collective behavior of the system is to add one or a few special agents into the group which are still treated as normal agents by the existing ones. We study how to lead a Vicsek-like flocking model to reach synchronization by adding special agents. A popular method is to add some simple leaders (fixed-headings agents. However, we add one intelligent agent, called 'shill', which uses online feedback information of the group to decide the shill's moving direction at each step. A novel strategy for the shill to coordinate the group is proposed. It is strictly proved that a shill with this strategy and a limited speed can synchronize every agent in the group. The computer simulations show the effectiveness of this strategy in different scenarios, including different group sizes, shill speed, and with or without noise. Compared to the method of adding some fixed-heading leaders, our method can guarantee synchronization for any initial configuration in the deterministic scenario and improve the synchronization level significantly in low density groups, or model with noise. This suggests the advantage and power of feedback information in intervention of collective behavior.

Review of actinide decorporation with chelating agents

Energy Technology Data Exchange (ETDEWEB)

Ansoborlo, E. [CEA Valrho, Dir. de l' Energie Nucleaire (DEN/DRCP/CETAMA), 30 - Marcoule (France); Amekraz, B.; Moulin, Ch. [CEA Saclay, Dept. de Physico-Chimie (DEN/DPC/SECR), 91 - Gif sur Yvette (France); Moulin, V. [CEA Saclay, Dir. du Developpement et de l' Innovation Nucleares (DEN/DDIN/MR), 91 - Gif Sur Yvette (France); Taran, F. [CEA Saclay (DSV/DBJC/SMMCB), 91 - Gif-sur-Yvette (France); Bailly, Th.; Burgada, R. [Centre National de la Recherche Scientifique (CNRS/LCSB/UMR 7033), 93 - Bobigny (France); Henge-Napoli, M.H. [CEA Valrho, Site de Marcoule (INSTN), 30 (France); Jeanson, A.; Den Auwer, Ch.; Bonin, L.; Moisy, Ph. [CEA Valrho, Dir. de l' Energie Nucleaire (DEN/DRCP/SCPS), 30 - Marcoule (France)

2007-10-15

In case of accidental release of radionuclides in a nuclear facility or in the environment, internal contamination (inhalation, ingestion or wound) with actinides represents a severe health risk to human beings. It is therefore important to provide effective chelation therapy or decorporation to reduce acute radiation damage, chemical toxicity, and late radiation effects. Speciation governs bioavailability and toxicity of elements and it is a prerequisite tool for the design and success of new ligands or chelating agents. The purpose of this review is to present the state-of-the-art of actinide decorporation within biological media, to recall briefly actinide metabolism, to list the basic constraints of actinide-ligand for development, to describe main tools developed and used for decorporation studies, to review mainly the chelating agents tested for actinides, and finally to conclude on the future trends in this field. (authors)

Organizations as Socially Constructed Agents in the Agent Oriented Paradigm

NARCIS (Netherlands)

G. Boella (Guido); L.W.N. van der Torre (Leon)

2005-01-01

htmlabstractIn this paper we propose a new role for the agent metaphor in the definition of the organizational structure of multiagent systems. The agent metaphor is extended to consider as agents also social entities like organizations, groups and normative systems, so that mental attitudes can

Influence of promoter/enhancer region haplotypes on MGMT transcriptional regulation: a potential biomarker for human sensitivity to alkylating agents.