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Sample records for biological control agent

  1. Ecological Complexity and the Success of Fungal Biological Control Agents

    Directory of Open Access Journals (Sweden)

    Guy R. Knudsen

    2014-01-01

    Full Text Available Fungal biological control agents against plant pathogens, especially those in soil, operate within physically, biologically, and spatially complex systems by means of a variety of trophic and nontrophic interspecific interactions. However, the biocontrol agents themselves are also subject to the same types of interactions, which may reduce or in some cases enhance their efficacy against target plant pathogens. Characterization of these ecologically complex systems is challenging, but a number of tools are available to help unravel this complexity. Several of these tools are described here, including the use of molecular biology to generate biocontrol agents with useful marker genes and then to quantify these agents in natural systems, epifluorescence and confocal laser scanning microscopy to observe their presence and activity in situ, and spatial statistics and computer simulation modeling to evaluate and predict these activities in heterogeneous soil habitats.

  2. 76 FR 3076 - Availability of an Environmental Assessment for a Biological Control Agent for Air Potato

    Science.gov (United States)

    2011-01-19

    ..., Lilioceris cheni, into the continental United States for use as a biological control agent to reduce the..., Lilioceris cheni, into the continental United States for use as a biological control agent to reduce the.... cheni, into the continental United States for use as a biological control agent to reduce the...

  3. 75 FR 69396 - Availability of an Environmental Assessment for a Biological Control Agent for Arundo donax

    Science.gov (United States)

    2010-11-12

    ... Assessment for a Biological Control Agent for Arundo donax AGENCY: Animal and Plant Health Inspection Service... a biological control agent to reduce the severity of Arundo donax infestations. We are making the... United States for use as a biological control agent to reduce the severity of Arundo donax...

  4. 75 FR 28232 - Availability of an Environmental Assessment for a Biological Control Agent for Hemlock Woolly...

    Science.gov (United States)

    2010-05-20

    ... a biological control agent to reduce the severity of hemlock woolly adelgid infestations. We are... continental United States for use as a biological control agent to reduce the severity of hemlock woolly... releasing an insect, L. osakensis, into the continental United States for use as a biological control...

  5. 75 FR 64984 - Availability of an Environmental Assessment for a Biological Control Agent for Hawkweeds

    Science.gov (United States)

    2010-10-21

    ... Assessment for a Biological Control Agent for Hawkweeds AGENCY: Animal and Plant Health Inspection Service... States as a biological control agent to reduce the severity of infestations of hawkweeds. We are making... subterminalis, into the continental United States for the biological control of hawkweeds (Hieracium...

  6. An abundant biological control agent does not provide a significant predator subsidy

    Science.gov (United States)

    Classical weed biological control agents, regardless of their effectiveness, may provide subsidies to predators and parasites. The chemically defended weevil Oxyops vitiosa Pascoe is a successful agent that was introduced to control the invasive tree Melaleuca quinquenervia. Two consecutive small ...

  7. Parasitoids as biological control agents of thrips pests

    NARCIS (Netherlands)

    Loomans, A.J.M.

    2003-01-01

    Keywords: Thysanoptera, Frankliniella occidentalis, Hymenoptera, Ceranisus menes, Ceranisus americensis, biological controlThe thesis presented here is the result of a joint European Research project "Biological Control of Thrips Pests". Specific aims of the project were to collect, evaluate, mass p

  8. Insect pathogens as biological control agents: Back to the future.

    Science.gov (United States)

    Lacey, L A; Grzywacz, D; Shapiro-Ilan, D I; Frutos, R; Brownbridge, M; Goettel, M S

    2015-11-01

    The development and use of entomopathogens as classical, conservation and augmentative biological control agents have included a number of successes and some setbacks in the past 1years. In this forum paper we present current information on development, use and future directions of insect-specific viruses, bacteria, fungi and nematodes as components of integrated pest management strategies for control of arthropod pests of crops, forests, urban habitats, and insects of medical and veterinary importance. Insect pathogenic viruses are a fruitful source of microbial control agents (MCAs), particularly for the control of lepidopteran pests. Most research is focused on the baculoviruses, important pathogens of some globally important pests for which control has become difficult due to either pesticide resistance or pressure to reduce pesticide residues. Baculoviruses are accepted as safe, readily mass produced, highly pathogenic and easily formulated and applied control agents. New baculovirus products are appearing in many countries and gaining an increased market share. However, the absence of a practical in vitro mass production system, generally higher production costs, limited post application persistence, slow rate of kill and high host specificity currently contribute to restricted use in pest control. Overcoming these limitations are key research areas for which progress could open up use of insect viruses to much larger markets. A small number of entomopathogenic bacteria have been commercially developed for control of insect pests. These include several Bacillus thuringiensis sub-species, Lysinibacillus (Bacillus) sphaericus, Paenibacillus spp. and Serratia entomophila. B. thuringiensis sub-species kurstaki is the most widely used for control of pest insects of crops and forests, and B. thuringiensis sub-species israelensis and L. sphaericus are the primary pathogens used for control of medically important pests including dipteran vectors. These pathogens

  9. Anti-tick biological control agents: assessment and future perspectives

    Science.gov (United States)

    Samish, M.; Ginsberg, H.S.; Glazer, I.; Bowman, Alan. S.; Nuttall, Patricia A.

    2008-01-01

    Widespread and increasing resistance to most available acaracides threatens both global livestock industries and public health. This necessitates better understanding of ticks and the diseases they transmit in the development of new control strategies. Ticks: Biology, Disease and Control is written by an international collection of experts and covers in-depth information on aspects of the biology of the ticks themselves, various veterinary and medical tick-borne pathogens, and aspects of traditional and potential new control methods. A valuable resource for graduate students, academic researchers and professionals, the book covers the whole gamut of ticks and tick-borne diseases from microsatellites to satellite imagery and from exploiting tick saliva for therapeutic drugs to developing drugs to control tick populations. It encompasses the variety of interconnected fields impinging on the economically important and biologically fascinating phenomenon of ticks, the diseases they transmit and methods of their control.

  10. Control of Lymantria dispar L. by biological agents

    Institute of Scientific and Technical Information of China (English)

    ZHANGGuo-cai; WANGYue-jie; YANGXiao-guang

    2005-01-01

    The experiment on control of Lymantria dispar L by using different kinds of biological measures, including nuclear polyhedrosis virus (NPV) of Lymantria dispar L., BtMP-342, sex-attractant as well as botanical insecticide, was carried out in the forest regions of Inner Mongolia in 2003. Two concentrations (2.632×106 PIB·ml-1 and 2.632×107 PIB·ml-1) of Lymantria dispar L. NPV were sprayed on the 2rd-instar-larvae of L. dispar and 70% and 77.8% control effect were obtained respectively. BtMP0-342 was applied to the 3rd- and 4th-instar larvae and the control effect was around 80%. The sex-attractant provided by Canada Pacific Forestry Research Center also showed a good result in trapping L. dispar adults. The self-produced botanical insecticide, which was extracted from a kind of poisonous plant distributed in Daxing'an Mountains, China, exhibited a good control result in controlling the larvae of L. dispar, and 82% mortality was observed when spraying primary liquid of the botanical insecticide on the 3rd-5th-instar-larvae in lab.

  11. 75 FR 28233 - Availability of an Environmental Assessment for a Biological Control Agent for Asian Citrus Psyllid

    Science.gov (United States)

    2010-05-20

    ... for use as a biological control agent to reduce the severity of Asian citrus psyllid infestations. We... continental United States for use as a biological control agent to reduce the severity of Asian citrus psyllid... include chemical control and the release of an alternative biological control agent, an encyrtid...

  12. Biological warfare agents.

    Science.gov (United States)

    Pohanka, Miroslav; Kuca, Kamil

    2010-01-01

    Biological warfare agents are a group of pathogens and toxins of biological origin that can be potentially misused for military or criminal purposes. The present review attempts to summarize necessary knowledge about biological warfare agents. The historical aspects, examples of applications of these agents such as anthrax letters, biological weapons impact, a summary of biological warfare agents and epidemiology of infections are described. The last section tries to estimate future trends in research on biological warfare agents.

  13. Current levels of suppression of waterhyacinth in Florida by classical biological control agents

    Science.gov (United States)

    Waterhyacinth, Eichhornia crassipes, has been a global target for classical biological control efforts for decades. In Florida, herbicides are the primary tactic employed, usually without regard for the activities of the three biological control agents introduced intentionally during the 1970's, na...

  14. Indirect ecological effects in invaded landscapes: Spillover and spillback from biological control agents to native analogues

    Science.gov (United States)

    Biological control remains an effective option for managing large-scale weed problems in natural areas. The predation or parasitism of biological control agents by other species present in the introduced range (biotic resistance) is well studied and is often cited as the cause for a lack of establis...

  15. Deciphering endophyte behaviour: the link between endophyte biology and efficacious biological control agents.

    Science.gov (United States)

    Card, Stuart; Johnson, Linda; Teasdale, Suliana; Caradus, John

    2016-08-01

    Endophytes associate with the majority of plant species found in natural and managed ecosystems. They are regarded as extremely important plant partners that provide improved stress tolerance to the host compared with plants that lack this symbiosis. Fossil records of endophytes date back more than 400 million years, implicating these microorganisms in host plant adaptation to habitat transitions. However, it is only recently that endophytes, and their bioactive products, have received meaningful attention from the scientific community. The benefits some endophytes can confer on their hosts include plant growth promotion and survival through the inhibition of pathogenic microorganisms and invertebrate pests, the removal of soil contaminants, improved tolerance of low fertility soils, and increased tolerance of extreme temperatures and low water availability. Endophytes are extremely diverse and can exhibit many different biological behaviours. Not all endophyte technologies have been successfully commercialised. Of interest in the development of the next generation of plant protection products is how much of this is due to the biology of the particular endophytic microorganism. In this review, we highlight selected case studies of endophytes and discuss their lifestyles and behavioural traits, and discuss how these factors contribute towards their effectiveness as biological control agents.

  16. Biological agents for whitefly control in Sardinian greenhouse tomatoes.

    Science.gov (United States)

    Nannini, M; Foddi, F; Manca, L; Pisci, R; Sanna, F

    2009-01-01

    To evaluate the effectiveness of alternative options for biocontrol of whiteflies in greenhouse tomatoes, an experiment was carried out during the cropping season 2005-2006 in one of Sardinia's major horticultural districts (S. Margherita di Pula, Cagliari, Italy). Twelve long-cycle and 17 short-cycle tomato crops (8 autumn and 9 spring crops) were surveyed. All of them were treated for insect pest control at the beginning of the growing season, but in 19 out of 29 cases whitefly natural enemies were also released (BCA greenhouses), at least four weeks after the last treatment. The following release programmes were tested: on autumn crops, 1 Macrolophus caliginosus and 12 Eretmocerus mundus/m2; on long-cycle crops, 1 M. caliginosus (released in autumn or spring) and 24 Encarsia formosa/m2 or 48 E. formosa/m2; on spring crops, 1 M. caliginosus and 24 E. formosa/m2 or 48 E. formosa/m2. The cost of each option was fixed at approximately 0.25 Euros/m2. The remaining greenhouses were maintained as controls (no BCA greenhouses). While whitefly and mirid populations were monitored monthly, whitefly species composition and mortality of immature stages were estimated at least twice during the growing season. On short-cycle autumn crops, the release of M. caliginosus and E. mundus produced negligible results in terms of Bemisia tabaci control. On long-cycle and spring crops, even though in June mortality rates in BCA greenhouses were found to be 2- to 3-fold higher than in no-BCA greenhouses, Trialeurodes vaporariorum population growth was not significantly affected by natural enemies. Among the beneficials tested, E. formosa proved to be the most effective; E. mundus and M. caliginosus did not establish well, probably owing to the persistence of insecticide residues, scarce prey availability and intense plant de-leafing. The presence of indigenous natural enemies of whiteflies was observed in most sites, but in general they contributed little to biological control. The

  17. Cyprinid herpesvirus 3 and its evolutionary future as a biological control agent for carp in Australia

    OpenAIRE

    Kenneth A. McColl; Sunarto, Agus; Holmes, Edward C.

    2016-01-01

    Biological invasions are a major threat to global biodiversity. Australia has experienced many invasive species, with the common carp (Cyprinus carpio L.) a prominent example. Cyprinid herpesvirus 3 (CyHV-3) has been proposed as a biological control (biocontrol) agent for invasive carp in Australia. Safety and efficacy are critical factors in assessing the suitability of biocontrol agents, and extensive host-specificity testing suggests that CyHV-3 is safe. Efficacy depends on the relationshi...

  18. Evaluation of biological control agents for mosquitoes control in artificial breeding places

    Institute of Scientific and Technical Information of China (English)

    Salim Abadi Yaser; Vatandoost Hassan; Rassi Yavar; Abai Mohammad Reza; Sanei Dehkordi Ali Reza; Paksa Azim

    2010-01-01

    Objective:To evaluate the entomological impact of chlorpyrifos-methyl,Bacillus thuringiensis, andGambusia affinis on mosquitoes control in artificial breeding places.Methods:A Latin square design with 4 replicates was performed in order to evaluate the efficacy of chlorpyrifos-methyl,Bacillus thuringiensis, andGambusia affinis on larva. The larvicide was applied at the dosage of 100 mg a.h/ha,Bacillus thuringiensis at the recommended dosage and 10 fishes per m2 were applied at 1í1 m2 artificial breeding sites. The larval densities for both anopheline and culicine were counted according to larvae /10 dippers prior and 24 h after application.Results:All three control agents are effective for mosquito density reduction, and the difference between the three agents and the control is significant (P<0.05). There is also significant difference among chlorpyrifos-methyl,Bacillus thuringiensis andGambusia affinis.Bacillus thuringiensisexhibited more reduction on mosquito larval density than fish and larvicide (P<0.05).Conclusions:Bacillus thuringiensis in comparison with two other agents is the appropriate method for larviciding in the breeding places. Although long term assessing for biological activities as well as monitoring and mapping of resistance is required.

  19. Enhancement of biological control agents for use against forest insect pests and diseases through biotechnology

    Science.gov (United States)

    Slavicek, James M.

    1991-01-01

    Research and development efforts in our research group are focused on the generation of more efficacious biological control agents through the techniques of biotechnology for use against forest insect pests and diseases. Effective biological controls for the gypsy moth and for tree fungal wilt pathogens are under development. The successful use of Gypchek, a formulation of the Lymantria dispar nuclear polyhedrosis virus (LdNPV), in gypsy moth control programs has generated considerable interest in that agent. As a consequence of its specificity, LdPNV has negligible adverse ecological impacts compared to most gypsy moth control agents. However, LdNPV is not competitive with other control agents in terms of cost and efficacy. We are investigating several parameters of LdNPV replication and polyhedra production in order to enhance viral potency and efficacy thus mitigating the current disadvantages of LdNPV for gypsy moth control, and have identified LdNPV variants that will facilitate these efforts. Tree endophytic bacteria that synthesize antifungal compounds were identified and an antibiotic compound from one of these bacteria was characterized. The feasibility of developing tree endophytes as biological control agents for tree vascular fungal pathogens is being investigated.

  20. Acquired natural enemies of the weed biological control agent Oxyops vitiosa (Coleoptera: Curculionidae)

    Science.gov (United States)

    The Australian curculionid Oxyops vitiosa Pascoe was introduced into Florida during 1997 as a biological control agent of the invasive tree Melaleuca quinquenervia (Cav.) S.T. Blake. Populations of the weevil increased rapidly and became widely distributed throughout much of the invasive tree’s adve...

  1. Host range of the inadvertent biological control agent Caloptilia triadicae: an invasive herbivore of Chinese tallowtree

    Science.gov (United States)

    An inadvertent biological control agent of the invasive weed Chinese tallowtree (Triadica sebifera) first appeared in North America in 2004. Identified as a Caloptilia triadicae, this leaf miner was found damaging T. sebifera saplings. In Gainesville, FL we exposed naturalized populations of C. tria...

  2. Investigating Biological Control Agents for Controlling Invasive Populations of the Mealybug Pseudococcus comstocki in France

    Science.gov (United States)

    Malausa, Thibaut; Delaunay, Mathilde; Fleisch, Alexandre; Groussier-Bout, Géraldine; Warot, Sylvie; Crochard, Didier; Guerrieri, Emilio; Delvare, Gérard; Pellizzari, Giuseppina; Kaydan, M. Bora; Al-Khateeb, Nadia; Germain, Jean-François; Brancaccio, Lisa; Le Goff, Isabelle; Bessac, Melissa; Ris, Nicolas; Kreiter, Philippe

    2016-01-01

    Pseudococcus comstocki (Hemiptera: Pseudococcidae) is a mealybug species native to Eastern Asia and present as an invasive pest in northern Italy and southern France since the start of the century. It infests apple and pear trees, grapevines and some ornamental trees. Biocontrol programmes against this pest proved successful in central Asia and North America in the second half of the 20th century. In this study, we investigated possible biocontrol agents against P. comstocki, with the aim of developing a biocontrol programme in France. We carried out systematic DNA-barcoding at each step in the search for a specialist parasitoid. First we characterised the French target populations of P. comstocki. We then identified the parasitoids attacking P. comstocki in France. Finally, we searched for foreign mealybug populations identified a priori as P. comstocki and surveyed their hymenopteran parasitoids. Three mealybug species (P. comstocki, P. viburni and P. cryptus) were identified during the survey, together with at least 16 different parasitoid taxa. We selected candidate biological control agent populations for use against P. comstocki in France, from the species Allotropa burrelli (Hymenoptera: Platygastridae) and Acerophagus malinus (Hymenoptera: Encyrtidae). The coupling of molecular and morphological characterisation for both pests and natural enemies facilitated the programme development and the rejection of unsuitable or generalist parasitoids. PMID:27362639

  3. Investigating Biological Control Agents for Controlling Invasive Populations of the Mealybug Pseudococcus comstocki in France.

    Directory of Open Access Journals (Sweden)

    Thibaut Malausa

    Full Text Available Pseudococcus comstocki (Hemiptera: Pseudococcidae is a mealybug species native to Eastern Asia and present as an invasive pest in northern Italy and southern France since the start of the century. It infests apple and pear trees, grapevines and some ornamental trees. Biocontrol programmes against this pest proved successful in central Asia and North America in the second half of the 20th century. In this study, we investigated possible biocontrol agents against P. comstocki, with the aim of developing a biocontrol programme in France. We carried out systematic DNA-barcoding at each step in the search for a specialist parasitoid. First we characterised the French target populations of P. comstocki. We then identified the parasitoids attacking P. comstocki in France. Finally, we searched for foreign mealybug populations identified a priori as P. comstocki and surveyed their hymenopteran parasitoids. Three mealybug species (P. comstocki, P. viburni and P. cryptus were identified during the survey, together with at least 16 different parasitoid taxa. We selected candidate biological control agent populations for use against P. comstocki in France, from the species Allotropa burrelli (Hymenoptera: Platygastridae and Acerophagus malinus (Hymenoptera: Encyrtidae. The coupling of molecular and morphological characterisation for both pests and natural enemies facilitated the programme development and the rejection of unsuitable or generalist parasitoids.

  4. Cardiocladius oliffi (Diptera: Chironomidae as a potential biological control agent against Simulium squamosum (Diptera: Simuliidae

    Directory of Open Access Journals (Sweden)

    Wilson Michael D

    2009-04-01

    Full Text Available Abstract Background The control of onchocerciasis in the African region is currently based mainly on the mass drug administration of ivermectin. Whilst this has been found to limit morbidity, it does not stop transmission. In the absence of a macrofilaricide, there is a need for an integrated approach for disease management, which includes vector control. Vector control using chemical insecticides is expensive to apply, and therefore the use of other measures such as biological control agents is needed. Immature stages of Simulium squamosum, reared in the laboratory from egg masses collected from the field at Boti Falls and Huhunya (River Pawnpawn in Ghana, were observed to be attacked and fed upon by larvae of the chironomid Cardiocladius oliffi Freeman, 1956 (Diptera: Chironomidae. Methods Cardiocladius oliffi was successfully reared in the rearing system developed for S. damnosum s.l. and evaluated for its importance as a biological control agent in the laboratory. Results Even at a ratio of one C. oliffi to five S. squamosum, they caused a significant decrease in the number of adult S. squamosum emerging from the systems (treatments. Predation was confirmed by the amplification of Simulium DNA from C. oliffi observed to have fed on S. squamosum pupae. The study also established that the chironomid flies could successfully complete their development on a fish food diet only. Conclusion Cardiocladius oliffi has been demonstrated as potential biological control agent against S. squamosum.

  5. PROTECTING ECOSYSTEMS BY WAY OF BIOLOGICAL CONTROL: CURSORY REFLECTIONS ON THE MAIN REGULATORY INSTRUMENTS FOR BIOLOGICAL CONTROL AGENTS, PRESENT AND FUTURE

    Directory of Open Access Journals (Sweden)

    R Alberts

    2013-06-01

    Full Text Available Although there are numerous threats to ecosystems and the resultant ecosystem services, alien and invasive plants (AIP have been identified as being one of the major causes of ecosystem destruction. In addressing the threat of alien and invasive plants through the use of various mechanisms, the regulatory framework imposed by legislation is key in ensuring that that controlling AIPs does in fact not do more harm than good. One such control mechanism, which has the potential to do wonders or wreak havoc if not adroitly implemented, is that of using biological control agents. This contribution provides a brief overview on the three main regulatory instruments used to control biological control agents in South Africa, namely the Conservation of Agricultural Resources Act 43 of 1983, the Agricultural Pests Act 36 of 1983 and the National Environmental Management: Biodiversity Act 10 of 2004. It also considers possible future developments on the regulation of biological control agents.

  6. Interaction of Ulocladium atrum, a Potential Biological Control Agent, with Botrytis cinerea and Grapevine Plantlets

    Directory of Open Access Journals (Sweden)

    Sébastien Ronseaux

    2013-09-01

    Full Text Available The effectiveness of biological control agent, Ulocladium atrum (isolates U13 and U16 in protecting Vitis vinifera L. cv. Chardonnay against gray mold disease caused by Botrytis cinerea, and simulation of the foliar defense responses was investigated. A degraded mycelium structure during cultural assay on potato dextrose agar revealed that U. atrum isolates U13 and U16 were both antagonistic to B. cinerea, mainly when isolates were inoculated two days before Botrytis. Under in vitro conditions, foliar application of U. atrum protected grapevine leaves against gray mold disease. An increase in chitinase activity was induced by the presence of U. atrum isolates indicating that the biological control agents triggered plant defense mechanisms. Moreover, U13 has the potential to colonize the grapevine plantlets and to improve their growth. The ability of U. atrum isolates to exhibit an antagonistic effect against B. cinerea in addition to their aptitude to induce plant resistance and to promote grapevine growth may explain a part of their biological activity. Hence, this study suggests that U. atrum provides a suitable biocontrol agent against gray mold in grapevines.

  7. Biological warfare agents

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    Duraipandian Thavaselvam

    2010-01-01

    Full Text Available The recent bioterrorist attacks using anthrax spores have emphasized the need to detect and decontaminate critical facilities in the shortest possible time. There has been a remarkable progress in the detection, protection and decontamination of biological warfare agents as many instrumentation platforms and detection methodologies are developed and commissioned. Even then the threat of biological warfare agents and their use in bioterrorist attacks still remain a leading cause of global concern. Furthermore in the past decade there have been threats due to the emerging new diseases and also the re-emergence of old diseases and development of antimicrobial resistance and spread to new geographical regions. The preparedness against these agents need complete knowledge about the disease, better research and training facilities, diagnostic facilities and improved public health system. This review on the biological warfare agents will provide information on the biological warfare agents, their mode of transmission and spread and also the detection systems available to detect them. In addition the current information on the availability of commercially available and developing technologies against biological warfare agents has also been discussed. The risk that arise due to the use of these agents in warfare or bioterrorism related scenario can be mitigated with the availability of improved detection technologies.

  8. Prospects for the use of biological control agents against Anoplophora in Europe.

    Science.gov (United States)

    Brabbs, Thomas; Collins, Debbie; Hérard, Franck; Maspero, Matteo; Eyre, Dominic

    2015-01-01

    This review summarises the literature on the biological control of Anoplophora spp. (Coleoptera: Cerambycidae) and discusses its potential for use in Europe. Entomopathogenic fungi: Beauveria brongniartii Petch (Hypocreales: Cordycipitaceae) has already been developed into a commercial product in Japan, and fungal infection results in high mortality rates. Parasitic nematodes: Steinernema feltiae Filipjev (Rhabditida: Steinernematidae) and Steinernema carpocapsae Weiser have potential for use as biopesticides as an alternative to chemical treatments. Parasitoids: a parasitoid of Anoplophora chinensis Forster, Aprostocetus anoplophorae Delvare (Hymenoptera: Eulophidae), was discovered in Italy in 2002 and has been shown to be capable of parasitising up to 72% of A. chinensis eggs; some native European parasitoid species (e.g. Spathius erythrocephalus) also have potential to be used as biological control agents. Predators: two woodpecker (Piciformis: Picidae) species that are native to Europe, Dendrocopos major Beicki and Picus canus Gmelin, have been shown to be effective at controlling Anoplophora glabripennis Motschulsky in Chinese forests. The removal and destruction of infested and potentially infested trees is the main eradication strategy for Anoplophora spp. in Europe, but biological control agents could be used in the future to complement other management strategies, especially in locations where eradication is no longer possible.

  9. Metarhizium anisopliae as a biological control agent against Hyalomma anatolicum (Acari: Ixodidae).

    Science.gov (United States)

    Suleiman, Elham A; Shigidi, M T; Hassan, S M

    2013-12-15

    In the Sudan, ticks and Tick-borne Diseases (TBDs) with subsequent costs of control and treatment are causing substantial economic loss. Control of ticks is mainly by chemical insecticides. The rising environmental hazards and problem of resistance has motivated research on biological agents as alternative methods of control. The present study aims at controlling livestock ticks using fungi for their unique mode of action besides their ability to adhere to the cuticle, to germinate and penetrate enzymatically. The study was conducted to evaluate the fungus Metarhizium anisopliae for tick control as an alternative mean to chemical acaricides. Pathogenicity of the fungus was tested on different developmental stages of the tick Hyalomma anatolicum. The fungus induced high mortality to flat immature stages. It, also, affected reproductive potential of the females. Egg laid, hatching percent, fertility and moulting percent of immature stages were significantly (p anisopliae to control ticks is discussed.

  10. Phenotypic charactheristics of fluorescent pseudomonss, biological control agent of lincat disease of temanggung tobacco

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    NINING NURUL AZIZAH

    2007-04-01

    Full Text Available Fluorescent pseudomonass isolated from local plants-rishosphere in temanggung controlled lincat disease of tobacco. This report describe phenotypic charactheristics of the bacteria in order to be used as a base for the development of the bacteria as a biological control agent of lincat disease. Phenotypic charactheristics of six isolates of fluorescent Pseudomonass which controlled lincat disease in the field were determined in the laboratory of Plant Bacteriology, Faculty of Agriculture, Gadjah Mada University. Plant pathogenicity tests were conducted by hypersensitive reaction into tobacco leaf and inoculation to tobacco plants. Antagonism test between fluorescent Pseudomonass and other candidate of biological control agents were also conducted. The results indicated that the bacteria were rod shape, Gram negative, positive reaction in catalase and oxidase tests. Nitrate reduce to nitrite, arginine was hydrolysed, fluorescent pigment were produced on King’s B medium, levan formation positive and all bacteria denitrifiy. The bacteria used urea, tween 80 and amylum were not hydrolised, poly--hydroxybutyrate was not accumulated in the cells. Negative reactions were observed for lysine decarboxylation, indol production, VP/MR reaction, and gelatn liquefation. Some compounds could be used as solely carbon sources. All isolates grew on the medium containing 2% NaCl. The best pH for growth was 6-7 and all isolates grew at 20-41C. Negative result were obtained for hypersensitive reaction and pathogenicity tests.

  11. Biological Warfare Agents

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    Dev Vrat Kamboj

    2006-10-01

    Full Text Available There is a long historic record of use of biological warfare (BW agents by warring countriesagainst their enemies. However, the frequency of their use has increased since the beginningof the twentieth century. World war I witnessed the use of anthrax agent against human beingsand animals by Germans, followed by large-scale field trials by Japanese against war prisonersand Chinese population during world war II. Ironically, research and development in biologicalwarfare agents increased tremendously after the Geneva Protocol, signed in 1925, because ofits drawbacks which were overcome by Biological and Toxin Weapons Convention (BTWC in1972. Biological warfare programme took back seat after the 1972 convention but biologicalagents regained their importance after the bioterrorist attacks of anthrax powder in 2001. In thelight of these attacks, many of which turned out to be hoax, general awareness is required aboutbiological warfare agents that can be used against them. This review has been written highlightingimportant biological warfare agents, diseases caused by them, possible therapies and otherprotection measures.

  12. Cyprinid herpesvirus 3 and its evolutionary future as a biological control agent for carp in Australia.

    Science.gov (United States)

    McColl, Kenneth A; Sunarto, Agus; Holmes, Edward C

    2016-12-08

    Biological invasions are a major threat to global biodiversity. Australia has experienced many invasive species, with the common carp (Cyprinus carpio L.) a prominent example. Cyprinid herpesvirus 3 (CyHV-3) has been proposed as a biological control (biocontrol) agent for invasive carp in Australia. Safety and efficacy are critical factors in assessing the suitability of biocontrol agents, and extensive host-specificity testing suggests that CyHV-3 is safe. Efficacy depends on the relationship between virus transmissibility and virulence. Based on observations from natural outbreaks, as well as the biology of virus-host interactions, we hypothesize that (i) close contact between carp provides the most efficient transmission of virus, (ii) transmission occurs at regular aggregations of carp that favour recrudescence of latent virus, and (iii) the initially high virulence of CyHV-3 will decline following its release in Australia. We also suggest that the evolution of carp resistance to CyHV-3 will likely necessitate the future release of progressively more virulent strains of CyHV-3, and/or an additional broad-scale measure(s) to complement the effect of the virus. If the release of CyHV-3 does go ahead, longitudinal studies are required to track the evolution of a virus-host relationship from its inception, and particularly the complex interplay between transmission, virulence and host resistance.

  13. The influence of flower morphology and nectar quality on the longevity of a parasitoid biological control agent

    NARCIS (Netherlands)

    Vattala, H.D.; Wratten, S.D.; Phillips, C.B.; Wäckers, F.L.

    2006-01-01

    Conservation biological control aims to enhance the efficacy of arthropod biological control agents, such as parasitoids, partly by providing them with access to floral nectar. However, the suitability of a flower species for providing nectar to a parasitoid is dependent on the morphologies of the p

  14. Efficacy of Chaetomium Species as Biological Control Agents against Phytophthora nicotianae Root Rot in Citrus.

    Science.gov (United States)

    Hung, Phung Manh; Wattanachai, Pongnak; Kasem, Soytong; Poeaim, Supattra

    2015-09-01

    Thailand is one of the largest citrus producers in Southeast Asia. Pathogenic infection by Phytophthora, however, has become one of major impediments to production. This study identified a pathogenic oomycete isolated from rotted roots of pomelo (Citrus maxima) in Thailand as Phytophthora nicotianae by the internal transcribed spacer ribosomal DNA sequence analysis. Then, we examined the in vitro and in vivo effects of Chaetomium globosum, Chaetomium lucknowense, Chaetomium cupreum and their crude extracts as biological control agents in controlling this P. nicotianae strain. Represent as antagonists in biculture test, the tested Chaetomium species inhibited mycelial growth by 50~56% and parasitized the hyphae, resulting in degradation of P. nicotianae mycelia after 30 days. The crude extracts of these Chaetomium species exhibited antifungal activities against mycelial growth of P. nicotianae, with effective doses of 2.6~101.4 µg/mL. Under greenhouse conditions, application of spores and methanol extracts of these Chaetomium species to pomelo seedlings inoculated with P. nicotianae reduced root rot by 66~71% and increased plant weight by 72~85% compared to that in the control. The method of application of antagonistic spores to control the disease was simple and economical, and it may thus be applicable for large-scale, highly effective biological control of this pathogen.

  15. Biology, host specificity tests, and risk assessment of the sawfly Heteroperreyia hubrichi, a potential biological control agent of Schinus terebinthifolius in Hawaii

    Science.gov (United States)

    Abstract. Heteroperreyia hubrichi Malaise (Hymenoptera: Pergidae), a foliage feeding sawfly of Schinus terebinthifolius Raddi (Sapindales: Anacardiaceae), was studied to assess its suitability as a classical biological control agent of this invasive weed in Hawaii. Nochoice host-specificity tests we...

  16. THE ROLE OF HALTICA SP. (COLEOPTERA: HALTICIDAE AS BIOLOGICAL CONTROL AGENT OF POLYGONUM CHINENSE

    Directory of Open Access Journals (Sweden)

    SUN JAY A

    1991-01-01

    Full Text Available The role of Haltica sp. (Coleoptera: Halticidae with emphasis on host specificity and damage potential in controlling Polygonum chinense was evaluated under laboratory condition. Starvation test of the weevil on 33 weeds and 14 crop plant species indicated that only 6 weed species were attacked: Polygonum chinense, P. nepalense, P. barbatum, P. longisetum, Ludwigia octovalvis and L. parennis with P. chinense as the most preferred host plant. Preliminary damage potential test indicated that a population of 0, 1,2 and 3 pairs of adult weevil reduced the percentage of fresh weight increment of P. chinense by 0; 46.2; 74.7 and 75.5% respectively. Field observations indicated that the larvae as well as adult weevils are potential biological control agents of P. chinense. Further studies are, however, on the host-range of this weevil.

  17. The role of bacillus-based biological control agents in integrated pest management systems: plant diseases.

    Science.gov (United States)

    Jacobsen, B J; Zidack, N K; Larson, B J

    2004-11-01

    ABSTRACT Bacillus-based biological control agents (BCAs) have great potential in integrated pest management (IPM) systems; however, relatively little work has been published on integration with other IPM management tools. Unfortunately, most research has focused on BCAs as alternatives to synthetic chemical fungicides or bactericides and not as part of an integrated management system. IPM has had many definitions and this review will use the national coalition for IPM definition: "A sustainable approach to managing pests by combining biological, cultural, physical and chemical tools in a way that minimizes economic, health and environmental risks." This review will examine the integrated use of Bacillus-based BCAs with disease management tools, including resistant cultivars, fungicides or bactericides, or other BCAs. This integration is important because the consistency and degree of disease control by Bacillus-based BCAs is rarely equal to the control afforded by the best fungicides or bactericides. In theory, integration of several tools brings stability to disease management programs. Integration of BCAs with other disease management tools often provides broader crop adaptation and both more efficacious and consistent levels of disease control. This review will also discuss the use of Bacillus-based BCAs in fungicide resistance management. Work with Bacillus thuringiensis and insect pest management is the exception to the relative paucity of reports but will not be the focus of this review.

  18. An intensive search for promising fungal biological control agents of ticks, particularly Rhipicephalus microplus.

    Science.gov (United States)

    Fernandes, Everton K K; Angelo, Isabele C; Rangel, Drauzio E N; Bahiense, Thiago C; Moraes, Aurea M L; Roberts, Donald W; Bittencourt, Vânia R E P

    2011-12-15

    Entomopathogenic fungi have been investigated worldwide as promising biological control agents of the cattle tick Rhipicephalus microplus. The current study evaluates the virulence of several fungal isolates to R. microplus larva in the laboratory as part of an effort to identify isolates with promise for effective biocontrol of R. microplus in the field. Sixty fungal isolates, encompassing 5 Beauveria spp. and 1 Engyodontium albus (=Beauveria alba), were included in this study. In addition to bioassays, the isolates were characterized morphologically and investigated as to their potential for conidial mass production. These findings were correlated with previous reports on the same fungal isolates of their natural UV-B tolerance (Fernandes et al., 2007), thermotolerance and cold activity (Fernandes et al., 2008), and genotypes (Fernandes et al., 2009). R. microplus larvae obtained from artificially infested calves were less susceptible to Beauveria bassiana infection than ticks acquired from naturally infested cattle from a different location. Isolates CG 464, CG 500 and CG 206 were among the most virulent Beauveria isolates tested in this study. All fungal isolates presented morphological features consistent with their species descriptions. Of the 53 B. bassiana isolates, five (CG 481, CG 484, CG 206, CG 235 and CG 487) had characteristics that qualified them as promising candidates for biological control agents of R. microplus, viz., mean LC(50) between 10(7) and 10(8)conidiaml(-1); produced 5000 conidia or more on 60mm(2) surface area of PDAY medium; and, in comparison to untreated (control) conidia, had the best conidial tolerances to UV-B (7.04 kJ m(-2)) and heat (45°C, 2h) of 50% or higher, and conidial cold (5°C, 15d) activity (mycelial growth) higher than 60%. The current study of 60 Beauveria spp. isolates, therefore, singles out a few (five) with high potential for controlling ticks under field conditions.

  19. Gluconic acid: an antifungal agent produced by Pseudomonas species in biological control of take-all.

    Science.gov (United States)

    Kaur, Rajvinder; Macleod, John; Foley, William; Nayudu, Murali

    2006-03-01

    Pseudomonas strain AN5 (Ps. str. AN5), a non-fluorescent Australian bacterial isolate, is an effective biological control (biocontrol) agent of the take-all disease of wheat caused by the fungus Gaeumannomyces graminis var. tritici (Ggt). Ps. str. AN5 controls Ggt by producing an antifungal compound which was purified by thin layer and column chromatography, and identified by NMR and mass spectroscopic analysis to be d-gluconic acid. Commercially bought pure gluconic acid strongly inhibited Ggt. Two different transposon mutants of Ps. str. AN5 which had lost take-all biocontrol did not produce d-gluconic acid. Gluconic acid production was restored, along with take-all biocontrol, when one of these transposon mutants was complemented with the corresponding open reading frame from wild-type genomic DNA. Gluconic acid was detected in the rhizosphere of wheat roots treated with the wild-type Ps. str. AN5, but not in untreated wheat or wheat treated with a transposon mutant strain which had lost biocontrol. The antifungal compounds phenazine-1-carboxylic acid and 2,4-diacetylphloroglucinol, produced by other Pseudomonads and previously shown to be effective in suppressing the take-all disease, were not detected in Ps. str. AN5 extracts. These results suggest that d-gluconic acid is the most significant antifungal agent produced by Ps. str. AN5 in biocontrol of take-all on wheat roots.

  20. Isolation, Characterization, and Identification of Biological Control Agent for Potato Soft Rot in Bangladesh

    Directory of Open Access Journals (Sweden)

    M. M. Rahman

    2012-01-01

    Full Text Available A total of 91 isolates of probable antagonistic bacteria of potato soft rot bacterium Erwinia carotovora subsp. carotovora (Ecc were extracted from rhizospheres and endophytes of various crop plants, different soil varieties, and atmospheres in the potato farming areas of Bangladesh. Antibacterial activity of the isolated probable antagonistic bacteria was tested in vitro against the previously identified most common and most virulent soft rot causing bacterial strain Ecc P-138. Only two isolates E-45 and E-65 significantly inhibited the in vitro growth of Ecc P-138. Physiological, biochemical, and carbon source utilization tests identified isolate E-65 as a member of the genus Bacillus and the isolate E-45 as Lactobacillus sp. The stronger antagonistic activity against Ecc P-138 was found in E-65 in vitro screening and storage potatoes. E-65 reduced the soft rot infection to 22-week storage potatoes of different varieties by 32.5–62.5% in model experiment, demonstrating its strong potential to be used as an effective biological control agent for the major pectolytic bacteria Ecc. The highest (62.5% antagonistic effect of E-65 was observed in the Granola and the lowest (32.7% of that was found in the Cardinal varieties of the Bangladeshi potatoes. The findings suggest that isolate E-65 could be exploited as a biocontrol agent for potato tubers.

  1. Fungal biological control agents for integrated management of Culicoides spp. (Diptera: Ceratopogonidae of livestock

    Directory of Open Access Journals (Sweden)

    B. W. Narladkar

    2015-02-01

    Full Text Available Aim: Entomopathogenic fungi Metarhizium anisopliae and Beauveria bassiana had wide host range against insects and hence these are being exploited as fungal bio-pesticide on a large scale. Both fungi are proved pesticides against many crop pests and farmers are well acquainted with their use on the field. Thus, research was aimed to explore the potency of these fungal spores against larval and adult Culicoides midges, a pest of livestock. Materials and Methods: In-vitro testing of both fungal biological control agents was undertaken in Petri dishes against field collected Culicoides larvae, while in plastic beakers against field collected blood-engorged female Culicoides midges. In-vivo testing was undertaken by spraying requisite concentration of fungal spores on the drainage channel against larvae and resting sites of adult Culicoides midges in the cattle shed. Lethal concentration 50 (LC50 values and regression equations were drawn by following probit analysis using SPSS statistical computerized program. Results: The results of this study revealed LC50 values of 2692 mg and 3837 mg (108 cfu/g for B. bassiana and M. anisopliae, respectively, against Culicoides spp. larvae. Death of Culicoides larvae due to B. bassiana showed greenish coloration in the middle of the body with head and tail showed intense blackish changes, while infection of M. anisopliae resulted in death of Culicoides larvae with greenish and blackish coloration of body along with total destruction, followed by desquamation of intestinal channel. The death of adult Culicoides midges were caused by both the fungi and after death growth of fungus were very well observed on the dead cadavers proving the efficacy of the fungus. Conclusion: Preliminary trials with both funguses (M. anisopliae, B. bassiana showed encouraging results against larvae and adults of Culicoides spp. Hence, it was ascertained that, these two fungal molecules can form a part of biological control and

  2. Risk assessment and stakeholder perceptions in novel biological control agent release: YST as a case study

    Science.gov (United States)

    The objectives of risk assessment are to learn about whether a candidate agent would be safe to use in the environment where release is planned, and to present such information in a clear, understandable format to regulators, stakeholders, and the public. Plant pathogens evaluated for biological co...

  3. Identification and Characterization of Lysobacter enzymogenes as a Biological Control Agent Against Some Fungal Pathogens

    Institute of Scientific and Technical Information of China (English)

    QIAN Guo-liang; HU Bai-shi; JIANG Ying-hua; LIU Feng-quan

    2009-01-01

    Strain OH11, a Gram-negative, nonspore forming, rod-shaped bacterium with powerful antagonistic activity, was isolated from rhizosphere of green pepper in Jiangsu Academy of Agricultural Sciences of China and characterized to determine its taxonomic position. 16S rRNA gene sequence analysis revealed that strain OH11 belongs to the Gammaproteobacteria and had the highest degree of sequence similarity to Lysobacter enzymogenes strain C3 (AY074793) (99%), Lysobacter enzyrnogenes strain N4-7 (U89965) (99%), Lysobacter antibioticus strain (AB019582) (97%), and Lysobacter gummosus strain (AB16136) (97%). Chemotaxonomic data revealed that strain OH11 possesses a quinine system with Q-8 as the predominant compound and C15:0 iso,C17:1 iso w9c as the predominant iso-branched fatty acids,all of which corroborated the assignment of strain OH11 to the genus Lysobacter. Results of DNA-DNA hybridization and physiological and biochemical tests clearly showed that strain OH11 was classified as Lysobacter enzymogenes. Strain OH11 could produce protease, chitinase, and β-1,3-glucanase. It showed strong in vitro antifungal activity against Rhizoctonia solani, Sclerotinia scletotiorum, and several other phytopathogenic fungi. This is the first report of identification and characterization of Lysobacter enzymogenes as a biological control agent of plant diseases in China.

  4. Studies on potential biological control agents of immature mosquitoes in sewage wastewater in southern California.

    Science.gov (United States)

    Mian, L S; Mulla, M S; Wilson, B A

    1986-09-01

    Three biological control agents, a copepod, Mesocyclops leuckarti pilosa, and two fish, Cyprinodon macularius and Poecilia reticulata, were evaluated for their survival in secondary sewage effluent (SSE) and predation potential on mosquito larvae. Results showed that the survival of M. l. pilosa was not significantly affected in SSE or SSE diluted (50%) with water. In predation tests, the copepod consumed from 50 to 90% of the 1st-instar larvae of Culex quinquefasciatus in 24 to 72 hr and P. reticulata fed on almost all stages (egg to pupa) of the test mosquitoes. Survivorship of P. reticulata and C. macularius in SSE was not significantly affected by SSE under both greenhouse and sewage aquaculture conditions. Poecilia reticulata was distributed towards the influent end and C. macularius towards the effluent end of the aquaculture ponds, indicating the former species can tolerate higher levels of pollution which exists at the influent end of the pond. However, low water temperature and dissolved oxygen may be detrimental to these fish species in sewage aquacultural systems.

  5. Commercial biological control agents targeted against plant-parasitic root-knot nematodes

    OpenAIRE

    Marie-Stéphane Tranier; Johan Pognant-Gros; Reynaldo De la Cruz Quiroz; Cristóbal Noé Aguilar González; Thierry Mateille; Sevastianos Roussos

    2014-01-01

    International audience; Root-knot nematodes are microscopic round worms, which cause severe agricultural losses. Their attacks affect the productivity by reducing the amount and the caliber of the fruits. Chemical control is widely used, but biological control appears to be a better solution, mainly using microorganisms to reduce the quantity of pests infecting crops. Biological control is developing gradually, and with time, more products are being marketed worldwide. They can be formulated ...

  6. Whole-Genome Sequence of Pseudomonas graminis Strain UASWS1507, a Potential Biological Control Agent and Biofertilizer Isolated in Switzerland

    Science.gov (United States)

    Crovadore, Julien; Calmin, Gautier; Chablais, Romain; Cochard, Bastien; Schulz, Torsten

    2016-01-01

    We report here the whole-genome shotgun sequence of the strain UASWS1507 of the species Pseudomonas graminis, isolated in Switzerland from an apple tree. This is the first genome registered for this species, which is considered as a potential and valuable resource of biological control agents and biofertilizers for agriculture.

  7. Phenology and temperature-dependent development of Ceutorhynchus assimilis, a potential biological control agent for Lepidium draba

    Science.gov (United States)

    Heart-podded hoary cress (Lepidium draba) is an alien weed that has invaded rangeland in the northwestern USA. A host race (i;e; host-specific biotype) of the weevil, Ceutorhynchus assimilis, is being evaluated as a prospective biological control agent. This biotype is only known from southern Eur...

  8. Potential biological control agents for management of cogongrass [Imperata cylindrica 15 (Cyperales: Poaceae)] in the southeastern USA

    Science.gov (United States)

    Cogongrass, Imperata cylindrica (L.) Palisot de Beauvois (Cyperales: Poaceae), is a noxious invasive weed in the southeastern USA. Surveys for potential biological control agents of cogongrass were conducted in Asia and East Africa from 2013 to 2016. Several insect herbivores were found that may hav...

  9. Biology and host range of Heterapoderopsis bicallosicollis; a potential biological control agent for Chinese tallow Triadica sebifera

    Science.gov (United States)

    Chinese tallow, Triadica sebifera, is an invasive weed that infests natural and agricultural areas of the southeastern USA. A candidate for biological control of Chinese tallow has been studied under quarantine conditions. The biology and host range of a primitive leaf feeding beetle, Heterapoderops...

  10. Suppressive composts from organic wastes as agents of biological control of fusariosis in Tatartan Republic (Russia)

    Science.gov (United States)

    Gumerova, Raushaniya; Galitskaya, Polina; Beru, Franchesca; Selivanovskaya, Svetlana

    2015-04-01

    pepton agar, the composts and their water extracts were checked towards their ability to inhibit growth of F. oxysporum. It was shown that three composts - CD, FPM and RD - possessed suppressiveness towards the model phytopathogen. From these three wastes, 28 bacterial and fungal strains were isolated and, in their turn, checked towards their ability to inhibit F. oxysporum. It was demonstrated that five of the isolated strains are highly suppressive to model test-object (the growth area of F. oxysporum did not exceed 30%), six of the stains were moderate suppressive (the growth area of F. oxysporum ranged from 35% to 60%), and other strains did not cause negative effects for the model phytopathogen. Further, we will check the composts and the isolated strains using the model system "soil - tomato plant - phytopathogen". As a result, effective composts and strains will be recommended as agents for biological control of fungal diseases in the region. Besides, the structure of bacterial and fungal community of the composts with suppressive properties will be assessed using 454-pyrosequencing.

  11. Prospects for the use of biological control agents against Anoplophora in Europe

    Science.gov (United States)

    This review summarises the literature on the biological control of Anoplophora spp. (Coleoptera: Cerambycidae) and discusses its potential for use in Europe. Entomopathogenic fungi: Beauveria brongniartii Petch (Hypocreales: Cordycipitaceae) has already been developed into a commercial product in Ja...

  12. Early-season flood enhances native biological control agents in Wisconsin cranberry

    Science.gov (United States)

    Biological control is predicated on the concept that crop plants are protected when predators suppress herbivore populations. However, many factors, including concurrent crop protection strategies, may modify the effectiveness of a predator in a given agroecosystem. In Wisconsin commercial cranberry...

  13. Utilization of an introduced weed biological control agent by a native parasitoid

    Science.gov (United States)

    A native parasitoid, Kalopolynema ema (Schauff and Grissell) (Hymenoptera, Mymaridae), that usually parasitizes the eggs of Megamelus davisi VanDuzee (Hemiptera, Delphacidae), has begun utilizing a new host, Megamelus scutellaris (Berg) (Hemiptera, Delphacidae), the introduced biological control age...

  14. Are Entomopathogenic Nematodes Effective Biological Control Agents Against the Carob Moth, Ectomyelois ceratoniae?

    Science.gov (United States)

    Memari, Zahra; Karimi, Javad; Kamali, Shokoofeh; Goldansaz, Seyed Hossein; Hosseini, Mojtaba

    2016-12-01

    The carob moth (Ectomyelois ceratoniae) is the key pest of pomegranate, which causes a significant percentage of losses in pomegranate orchards and warehouses of Iran annually. The pest larvae are characterized by displaying a cryptic behavior within the fruit, which avoids most routine control techniques, especially chemical method. The low efficiency of traditional measurements and also the rich species diversity of natural enemies within the infested fruits highlight the necessity of exploring effective control methods, especially environmental friendly approaches. Entomopathogenic nematodes (EPNs) are a group of biological control agents that actively search for the host, including those in a cryptic habitat like the carob moth larvae within infested fruits. Here, we assumed that treatment of the infested and dropped fruits with EPNs may provide new insight into the management of the carob moth. Three species of EPNs, Steinernema feltiae, S. carpocapsae, and Heterorhabditis bacteriophora were selected and used in a series of in vitro and in vivo experiments. In preliminary assays, the EPNs species were used with different concentrations of infective juveniles (IJs) (0, 1, 5, 10, 25, and 50 IJ/larvae) in 2-cm diam. plates. The mortality rates of the laboratory tests were 79.75% and 76.5% for S. feltiae and S. carpocapsae, corresponded to LC50 value of 2.02 IJ/larva for S. feltiae and 2.05 IJ/larva for S. carpocapsae. On the contrary, H. bacteriophora demonstrated low virulence on the pest larvae in petri tests with a LC50 = 426.92 IJ/larva. Hence, both Steinernema species were selected for subsequent experiments. The penetration rate for S. feltiae and S. carpocapsae into the hemocoel of the pest was 43% and 31%, respectively, and the corresponding reproduction rate was 15,452 IJ/larva for S. feltiae and 18,456 IJ/larva for S. carpocapsae. The gathered data from those in vitro tests were used for a field assay. Different concentrations (5, 10, 50, 100, and 160

  15. Predicting spillover risk to non-target plants pre-release: Bikasha collaris a potential biological control agent of Chinese tallowtree (Triadica sebifera)

    Science.gov (United States)

    Quarantine host range tests accurately predict direct risk of biological control agents to non-target species. However, a well-known indirect effect of biological control of weeds releases is spillover damage to non-target species. Spillover damage may occur when the population of agents achieves ou...

  16. Diapause in Abrostola asclepiadis (Lepidoptera: Noctuidae) may make for an ineffective weed biological control agent

    Science.gov (United States)

    Pale and black swallow-wort (Vincetoxicum rossicum and V. nigrum; Apocynaceae, subfamily Asclepiadoideae) are perennial vines from Europe that are invasive in various terrestrial habitats in the northeastern USA and southeastern Canada. A classical weed biological control program has been in develop...

  17. Evaluation of Amitus fuscipennis as biological control agent of Trialeurodes vaporariorum on bean in Colombia

    NARCIS (Netherlands)

    Manzano Martinez, M.R.

    2000-01-01

    The research described in this thesis concerns the study of a natural enemy of whiteflies, Amitus fuscipennis MacGown & Nebeker under Colombian field and laboratory conditions. The general aim of the project was to study whether biological control of Trialeurodes vaporariorum (Westwood) with A. fusc

  18. Release of the Biological Control Agent Puccinia jaceae var. solstitialis for Management of Yellow Starthistle at Fort Hunter Liggett, CA

    Science.gov (United States)

    2010-07-01

    the effectiveness of the rust fungus, Puccinia jaceae var. solstitialis, as a biological control agent for management of yellow starthistle...multiple generations of urediniospores that become airborne and can infect other leaves and plants thus increasing the incidence, intensity, and spatial...spread of the disease (Fisher et al. 2008). During plant senescence, many rust fungi produce survival spores (teliospores) that over- winter. The

  19. Commercial Biological Control Agents Targeted Against Plant-Parasitic Root-knot Nematodes

    Directory of Open Access Journals (Sweden)

    Marie-Stéphane Tranier

    2014-12-01

    Full Text Available Root-knot nematodes are microscopic round worms, which cause severe agricultural losses. Their attacks affect the productivity by reducing the amount and the caliber of the fruits. Chemical control is widely used, but biological control appears to be a better solution, mainly using microorganisms to reduce the quantity of pests infecting crops. Biological control is developing gradually, and with time, more products are being marketed worldwide. They can be formulated with bacteria, viruses or with filamentous fungi, which can destroy and feed on phytoparasitic nematodes. To be used by the farmers, biopesticides must be legalized by the states, which has led to the establishment of a legal framework for their use, devised by various governmental organizations.

  20. 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 FACT SHEET What riot control agents are Riot control agents (sometimes referred to ...

  1. Efficacy of Bacillus subtilis V26 as a biological control agent against Rhizoctonia solani on potato.

    Science.gov (United States)

    Ben Khedher, Saoussen; Kilani-Feki, Olfa; Dammak, Mouna; Jabnoun-Khiareddine, Hayfa; Daami-Remadi, Mejda; Tounsi, Slim

    2015-12-01

    The aim of this study is to evaluate the efficacy of the strain Bacillus subtilis V26, a local isolate from the Tunisian soil, to control potato black scurf caused by Rhizoctonia solani. The in vitro antifungal activity of V26 significantly inhibited R. solani growth compared to the untreated control. Microscopic observations revealed that V26 caused considerable morphological deformations of the fungal hyphae such as vacuolation, protoplast leakage and mycelia crack. The most effective control was achieved when strain V26 was applied 24h prior to inoculation (protective activity) in potato slices. The antagonistic bacterium V26 induced significant suppression of root canker and black scurf tuber colonization compared to untreated controls with a decrease in incidence disease of 63% and 81%, respectively, and promoted plant growth under greenhouse conditions on potato plants. Therefore, B. subtilis V26 has a great potential to be commercialized as a biocontrol agent against R. solani on potato crops.

  2. Climate warming increases biological control agent impact on a non-target species

    Science.gov (United States)

    Lu, Xinmin; Siemann, Evan; He, Minyan; Wei, Hui; Shao, Xu; Ding, Jianqing

    2015-01-01

    Climate change may shift interactions of invasive plants, herbivorous insects and native plants, potentially affecting biological control efficacy and non-target effects on native species. Here, we show how climate warming affects impacts of a multivoltine introduced biocontrol beetle on the non-target native plant Alternanthera sessilis in China. In field surveys across a latitudinal gradient covering their full distributions, we found beetle damage on A. sessilis increased with rising temperature and plant life history changed from perennial to annual. Experiments showed that elevated temperature changed plant life history and increased insect overwintering, damage and impacts on seedling recruitment. These results suggest that warming can shift phenologies, increase non-target effect magnitude and increase non-target effect occurrence by beetle range expansion to additional areas where A. sessilis occurs. This study highlights the importance of understanding how climate change affects species interactions for future biological control of invasive species and conservation of native species. PMID:25376303

  3. Climate warming increases biological control agent impact on a non-target species.

    Science.gov (United States)

    Lu, Xinmin; Siemann, Evan; He, Minyan; Wei, Hui; Shao, Xu; Ding, Jianqing

    2015-01-01

    Climate change may shift interactions of invasive plants, herbivorous insects and native plants, potentially affecting biological control efficacy and non-target effects on native species. Here, we show how climate warming affects impacts of a multivoltine introduced biocontrol beetle on the non-target native plant Alternanthera sessilis in China. In field surveys across a latitudinal gradient covering their full distributions, we found beetle damage on A. sessilis increased with rising temperature and plant life history changed from perennial to annual. Experiments showed that elevated temperature changed plant life history and increased insect overwintering, damage and impacts on seedling recruitment. These results suggest that warming can shift phenologies, increase non-target effect magnitude and increase non-target effect occurrence by beetle range expansion to additional areas where A. sessilis occurs. This study highlights the importance of understanding how climate change affects species interactions for future biological control of invasive species and conservation of native species.

  4. The Use and Exchange of Biological Control Agents for Food and Agriculture

    Institute of Scientific and Technical Information of China (English)

    J.C.van; Lenteren; M.J.W.Cock; J.Brodeur; B.Barratt; F.Bigler; K.Bolckmans; F.Haas; P.G.Mason; J.R.P.Parra

    2010-01-01

    The report sets out to summarize the past and current situation regarding the practice of biologicalcontrol inrelationtothe use and exchange of genetic resources relevant for BCAs.It considers the twomain categories of biological control:classical and augmentative.Allowing access to BCAs for use inanother country imposes no risk of liability to the source country.Local scientific knowledge abouthabitats,fauna andflora,can be helpful

  5. Factors affecting the flight capacity of Tetrastichus planipennisi (Hymenoptera: Eulophidae), a classical biological control agent of Agrilus planipennis (Coleoptera: Buprestidae).

    Science.gov (United States)

    Fahrner, Samuel J; Lelito, Jonathan P; Blaedow, Karen; Heimpel, George E; Aukema, Brian H

    2014-12-01

    The dispersal characteristics of a biological control agent can have direct implications on the ability of that agent to control populations of a target host. Tetrastichus planipennisi Yang (Hymenoptera: Eulophidae) is a parasitic wasp native to eastern Asia that has been introduced into the United States as part of a classical biological control program against the emerald ash borer Agrilus planipennis Fairmaire (Coleoptera: Buprestidae). We used computer-monitored flight mills to investigate the role of age, feeding status, mating status, and size on the flight capacity of female T. planipennisi over a 24-h period. We also compared flight capacity between sexes. Flight distance of female T. planipennisi representative of populations released in the biological control program averaged 1.26 km in 24 h with a maximum flight of just over 7 km. Median flight distance, however, was 422 m. The flight capacity of females fed a honey-water solution was 41× that of females provided only water, who flew very little. Larger females were capable of flying farther distances, but age did not affect the flight capacity of females up to 70 d posteclosion. Females dispersed 6× farther than did their smaller, male counterparts. The implications of our findings to host-parasitoid interactions and release protocols for distributing T. planipennisi are discussed.

  6. Custo da produção de Orius insidiosus como agente de controle biológico Production cost of Orius insidiosus as biological control agent

    Directory of Open Access Journals (Sweden)

    Simone Martins Mendes

    2005-05-01

    Full Text Available O objetivo deste trabalho foi estimar o custo de produção por indivíduo do predador Orius insidiosus (Say, levando-se em consideração um modelo de criação em laboratório. Nos cálculos, considerou-se uma produção de 33.000 percevejos mês-1, dos quais 14,5% foram para manutenção da criação e o restante, ou seja, 28.272 indivíduos, para comercialização. Os preços dos materiais e equipamentos utilizados na criação foram cotados em dólares americanos na proporção de R$ 2,84 por US$ 1,00. O custo estimado de cada percevejo predador foi da ordem de US$ 0,069, levando-se em consideração custos fixos e variáveis. Este custo é um parâmetro decisivo na criação massal de Orius insidiosus e em sua utilização como agente de controle em programas de controle biológico de tripes.The objective of this work was to estimate the individual production cost of the predator Orius insidiosus (Say in laboratory. A rearing model of O. insidiosus in laboratory was used to reach production of 33,000 individuals month-1, using 14.5% to maintain the predator rearing in the laboratory and 28,272 individuals for commercialization. The prices of different materials and equipments used on predator rearing were fixed at US$ 1.00 = R$ 2.84. The estimated cost for production of each adult predator was US$ 0.069, taking all the fixed and variable costs. This parameter is crucial to support O. insidiosus mass rearing, and to use this predator as biocontrol agent in biological control program of thrips.

  7. Effects of pollutant accumulation by the invasive weed saltcedar (Tamarix ramosissima) on the biological control agent Diorhabda elongata (Coleoptera: Chrysomelidae)

    Energy Technology Data Exchange (ETDEWEB)

    Sorensen, Mary A. [Department of Entomology, University of California, Riverside, CA 92521 (United States)], E-mail: mary.sorensen@ucr.edu; Parker, David R. [Department of Environmental Science, University of California, Riverside, CA 92521 (United States); Trumble, John T. [Department of Entomology, University of California, Riverside, CA 92521 (United States)

    2009-02-15

    Hydroponic greenhouse studies were used to investigate the effect of four anthropogenic pollutants (perchlorate (ClO{sub 4}{sup -}), selenium (Se), manganese (Mn), and hexavalent chromium (Cr (VI))) on the biological control agent Diorhabda elongata Brulle. Contaminant concentrations were quantified for experimental Tamarix ramosissima Ledab. plants and D. elongata beetles. Growth of larvae was significantly reduced by Se contamination, but was not affected by the presence of perchlorate, Mn, or Cr (VI). All of the contaminants were transferred from plants to D. elongata beetles. Only Cr (VI) was accumulated at greater levels in beetles than in their food. Because T. ramosissima grows in disturbed areas, acquires salts readily, and utilizes groundwater, this plant is likely to accumulate anthropogenic pollutants in contaminated areas. This study is one of the first to investigate the potential of an anthropogenic pollutant to influence a weed biological control system. - The presence of Se, but not perchlorate, Mn, or Cr (VI), in foliage of the invasive weed saltcedar was shown to reduce growth of the biological control agent Diorhabda elongata.

  8. A foam formulation for the delivery of microbial biological control agents

    Science.gov (United States)

    Common surfactants and foaming agents are toxic to most microorganisms. To identify suitable foaming agents for use with microbes, several classes of surfactants/foaming agents were screened for compatibility with blastospores of Paecilomyces fumosoroseus. The surfactants were assayed to determine...

  9. Infection of two non-target grasshoppers by the biological control agent Metarhizium anisopliae var. acridum in the Sahel

    DEFF Research Database (Denmark)

    Fisker, E. N.; Eilenberg, J.; Langewald, J.;

    2006-01-01

    Fungal isolates from grasshoppers of the family Acrididae are suspected to be less virulent to grasshoppers of the family Pyrgomorphidae. The biological control agent Metarhizium anisopliae var. acridum was isolated from an acridid and is thus hypothesized to be less virulent to pyrgomorphids....... The susceptibility of two non-target pyrgomorphids, Pyrgomorpha cognata and Poekilocerus bufonius hieroglyphicus, to M. anisopliae was tested in the field. Results show that P. cognata under field conditions is as susceptible to infection by M. anisopliae as acridids, whereas P. b. hieroglyphicus is less susceptible...

  10. First report of an egg parasitoid reared from Neomusotima conspurcatalis (Lepidoptera: Crambidae) a biological control agent of Lygodium microphyllum (Schizaeales: Lygodiaceae)

    Science.gov (United States)

    Neomusotima conspurcatalis (Lepidoptera: Crambidae) was first released in Florida as a biological control agent of Lygodium microphyllum (Polypodiales: Lygodiaceae), Old World climbing fern, in 2008. The first egg parasitoid, a Trichogramma sp. (Hymenoptera: Trichogrammatidae), was reared from N. co...

  11. Biotech drugs : biological therapeutic agents

    OpenAIRE

    Grech, Godfrey; Fenech, Anthony

    2009-01-01

    The recent years has seen significant growth in a new therapeutic approach to the management of disease. Biological therapeutic agents, constitute a broad category of drugs, usually generated by recombinant techniques from living organisms. These therapies revolutionise the traditional approaches to drug design and development, and regulatory agencies have been swift in developing the necessary structures to ensure their optimal use.

  12. Biologic Agents in Inflammatory Eye Disease

    Directory of Open Access Journals (Sweden)

    Chiara Posarelli

    2011-01-01

    Full Text Available Non-infectious uveitis is a potentially sight threatening disease. Along the years, several therapeutic strategies have been proposed as a means to its treatment, including local and systemic steroids, immunosuppressives and more recently, biologic agents. The introduction of biologics can be defined as a new era: biologic therapies provide new options for patients with refractory and sight threatening inflammatory disorders. The availability of such novel treatment modalities has markedly improved the therapy of uveitis and considerably increased the possibility of long-term remissions. This article provides a review of current literature on biologic agents, such as tumor necrosis factor blockers, anti-interleukins and other related biologics, such as interferon alpha, for the treatment of uveitis. Several reports describe the efficacy of biologics in controlling a large number of refractory uveitides, suggesting a central role in managing ocular inflammatory diseases. However, there is still lack of randomized controlled trials to validate most of their applications. Biologics are promising drugs for the treatment of uveitis, showing a favorable safety and efficacy profile. On the other hand, lack of evidence from randomized controlled studies limits our understanding as to when commence treatment, which agent to choose, and how long to continue therapy. In addition, high cost and the potential for serious and unpredictable complications have very often limited their use in uveitis refractory to traditional immunosuppressive therapy.

  13. Biologic agents in inflammatory eye disease.

    Science.gov (United States)

    Posarelli, Chiara; Arapi, Ilir; Figus, Michele; Neri, Piergiorgio

    2011-10-01

    Non-infectious uveitis is a potentially sight threatening disease. Along the years, several therapeutic strategies have been proposed as a means to its treatment, including local and systemic steroids, immunosuppressives and more recently, biologic agents. The introduction of biologics can be defined as a new era: biologic therapies provide new options for patients with refractory and sight threatening inflammatory disorders. The availability of such novel treatment modalities has markedly improved the therapy of uveitis and considerably increased the possibility of long-term remissions. This article provides a review of current literature on biologic agents, such as tumor necrosis factor blockers, anti-interleukins and other related biologics, such as interferon alpha, for the treatment of uveitis. Several reports describe the efficacy of biologics in controlling a large number of refractory uveitides, suggesting a central role in managing ocular inflammatory diseases. However, there is still lack of randomized controlled trials to validate most of their applications. Biologics are promising drugs for the treatment of uveitis, showing a favorable safety and efficacy profile. On the other hand, lack of evidence from randomized controlled studies limits our understanding as to when commence treatment, which agent to choose, and how long to continue therapy. In addition, high cost and the potential for serious and unpredictable complications have very often limited their use in uveitis refractory to traditional immunosuppressive therapy.

  14. Isolation and characterization of soil Streptomyces species as potential biological control agents against fungal plant pathogens.

    Science.gov (United States)

    Evangelista-Martínez, Zahaed

    2014-05-01

    The use of antagonist microorganisms against fungal plant pathogens is an attractive and ecologically alternative to the use of chemical pesticides. Streptomyces are beneficial soil bacteria and potential candidates for biocontrol agents. This study reports the isolation, characterization and antagonist activity of soil streptomycetes from the Los Petenes Biosphere Reserve, a Natural protected area in Campeche, Mexico. The results showed morphological, physiological and biochemical characterization of six actinomycetes and their inhibitory activity against Curvularia sp., Aspergillus niger, Helminthosporium sp. and Fusarium sp. One isolate, identified as Streptomyces sp. CACIS-1.16CA showed the potential to inhibit additional pathogens as Alternaria sp., Phytophthora capsici, Colletotrichum sp. and Rhizoctonia sp. with percentages ranging from 47 to 90 %. This study identified a streptomycete strain with a broad antagonist activity that could be used for biocontrol of plant pathogenic fungi.

  15. Reducing losses inflicted by insect pests on cashew, using weaver ants as a biological control agent

    DEFF Research Database (Denmark)

    Anato, Florence; Wargui, Rosine; Sinzogan, Antonio

    2015-01-01

    BACKGROUND: Cashew (Anacardium occidentale Linnaeus) is the largest agricultural export product in Benin. However, yields and quality are lost due to inefficient pest control. Weaver ants (Oecophylla spp.) may control pests in this crop as they eat and deter pests. In Benin, cashew pest damages, ...

  16. Marine isolates of Trichoderma spp. as potential halotolerant agents of biological control for arid-zone agriculture.

    Science.gov (United States)

    Gal-Hemed, Inbal; Atanasova, Lea; Komon-Zelazowska, Monika; Druzhinina, Irina S; Viterbo, Ada; Yarden, Oded

    2011-08-01

    The scarcity of fresh water in the Mediterranean region necessitates the search for halotolerant agents of biological control of plant diseases that can be applied in arid-zone agriculture irrigated with saline water. Among 29 Trichoderma strains previously isolated from Mediterranean Psammocinia sp. sponges, the greatest number of isolates belong to the Trichoderma longibrachiatum-Hypocrea orientalis species pair (9), H. atroviridis/T. atroviride (9), and T. harzianum species complex (7), all of which are known for high mycoparasitic potential. In addition, one isolate of T. asperelloides and two putative new species, Trichoderma sp. O.Y. 14707 and O.Y. 2407, from Longibrachiatum and Strictipilosa clades, respectively, have been identified. In vitro salinity assays showed that the ability to tolerate increasing osmotic pressure (halotolerance) is a strain- or clade-specific property rather than a feature of a species. Only a few isolates were found to be sensitive to increased salinity, while others either were halotolerant or even demonstrated improved growth in increasingly saline conditions. In vitro antibiosis assays revealed strong antagonistic activity toward phytopathogens due to the production of both soluble and volatile metabolites. Two marine-derived Trichoderma isolates, identified as T. atroviride and T. asperelloides, respectively, effectively reduced Rhizoctonia solani damping-off disease on beans and also induced defense responses in cucumber seedlings against Pseudomonas syringae pv. lachrimans. This is the first inclusive evaluation of marine fungi as potential biocontrol agents.

  17. Colitis associated with biological agents

    Institute of Scientific and Technical Information of China (English)

    Hugh James Freeman

    2012-01-01

    In the past,there has been considerable focus on a host of drugs and chemicals that may produce colonic toxicity.Now,a variety of new biological monoclonal antibody agents,usually administered by infusion,have appeared in the clinical realm over the last decade or so to treat different chronic inflammatory or malignant disorders.For some of these agents,adverse effects have been documented,including apparently new forms of immune-mediated inflammatory bowel disease.In some,only limited symptoms have been recorded,but in others,severe colitis with serious complications,such as bowel perforation has been recorded.In others,adverse effects may have a direct vascular or ischemic basis,while other intestinal effects may be related to a superimposed infection.Some new onset cases of ulcerative colitis or Crohn's disease may also be attributed to the same agents used to treat these diseases,or be responsible for disease exacerbation.Dramatic and well documented side effects have been observed with ipilimumab,a humanized monoclonal antibody developed to reduce and overcome cytotoxic T-lymphocyte antigen 4,a key negative feedback regulator of the T-cell anti-tumor response.This agent has frequently been used in the treatment of different malignancies,notably,malignant melanoma.Side effects with this agent occur in up to 40% and these are believed to be largely immune-mediated.One of these is a form of enterocolitis that may be severe,and occasionally,fatal.Other agents include rituximab (an antiCD20 monoclonal antibody),bevacizumab (a monoclonal antibody against the vascular endothelial growth factor) and anti-tumor necrosis factor agents,including infliximab,adalimumab and etanercept.

  18. Agent-Based Models and Optimal Control in Biology: A Discrete Approach

    Science.gov (United States)

    2012-01-01

    different parts of the human body to cure diseases such as hypertension, cancer, or heart disease. And we need to control microbes for the efficient...dynamics to remain the same, and how we can verify that this is indeed the case. Since we are using the model with a specific control objective in mind ...similar to the approach pioneered by Descartes and his introduction of a coordinate system. In the plane, for instance, a Cartesian coordinate system

  19. Livestock as a potential biological control agent for an invasive wetland plant

    Directory of Open Access Journals (Sweden)

    Brian R. Silliman

    2014-09-01

    Full Text Available Invasive species threaten biodiversity and incur costs exceeding billions of US$. Eradication efforts, however, are nearly always unsuccessful. Throughout much of North America, land managers have used expensive, and ultimately ineffective, techniques to combat invasive Phragmites australis in marshes. Here, we reveal that Phragmites may potentially be controlled by employing an affordable measure from its native European range: livestock grazing. Experimental field tests demonstrate that rotational goat grazing (where goats have no choice but to graze Phragmites can reduce Phragmites cover from 100 to 20% and that cows and horses also readily consume this plant. These results, combined with the fact that Europeans have suppressed Phragmites through seasonal livestock grazing for 6,000 years, suggest Phragmites management can shift to include more economical and effective top-down control strategies. More generally, these findings support an emerging paradigm shift in conservation from high-cost eradication to economically sustainable control of dominant invasive species.

  20. Evaluation of mortality factors using life table analysis of Gratiana boliviana, a biological control agent of tropical soda apple in Florida

    Science.gov (United States)

    Tropical soda apple (TSA), Solanum viarum Dunal (Solanaceae), has invaded many pastures and natural areas in Florida. The biological control agent Gratiana boliviana Spaeth (Coleoptera: Chrysomelidae) is providing adequate control of TSA stands in South and Central Florida. However, poor or no es...

  1. Antibiotics production by bacterial agents and its role in biological control

    NARCIS (Netherlands)

    Wang, G.; Raaijmakers, J.M.

    2004-01-01

    Using bacteria to control plant diseases is one of the main strategies in plant protection, and its mechanism is commonly thought to be the production of antibiotics by bacteria. The produced antibiotics not only have structural diversity, but also have broad-spectrum activity against many pathogens

  2. Diversity and biological control of Sclerotium rolfsii, causal agent of stem rot of groundnut

    NARCIS (Netherlands)

    Lê, N.C.

    2011-01-01

    Groundnut (Arachis hypogaea L.) is an economically important legume crop in Vietnam and many other countries worldwide. Stem rot disease, caused by the soil-borne fungus Sclerotium rolfsii Sacc., is a major yield limiting factor in groundnut cultivation. Current control methods

  3. Biology and reproductive parameters of the brown lygodium moth, Neomusotima conspurcatalis--a new biological control agent of Old World climbing fern in Florida.

    Science.gov (United States)

    Boughton, Anthony J; Pemberton, Robert W

    2012-04-01

    Neomusotima conspurcatalis Warren was first released in Florida as a weed biological control agent against Old World climbing fern in 2008, and readily established large field populations. A related biocontrol agent, Austromusotima camptozonale, had previously failed to establish despite several years of releases. Life history studies were conducted to determine whether aspects of the reproductive biology of N. conspurcatalis might account for these different outcomes. At 26.5°C, development from egg to adult averaged 22.2 ± 0.1 d, with 75% of larvae emerging as adults. The sex ratio averaged 1:0.8 (♂:♀), with both sexes emerging at the same time. Female moths typically mated once, on the first night after emergence, and began oviposition the next night. Females laid half their eggs on the first night and lived an average of 10.7 ± 0.8 d. Individual females maintained in cages with a male-biased sex ratio (3♂:1♀) produced significantly more larvae over their lifetime (140 ± 6.6 larvae) than individual females maintained at a ratio of 1♂:1♀ (111 ± 9.1 larvae). Sexual selection, either through 'male-male competition' or 'female choice' was likely responsible for this result, because there were no significant differences in mating frequency, duration of ovipositional period or female longevity to otherwise explain the difference. Two-fold greater lifetime reproductive output (average 127 ± 6.3 larvae) and deposition of half this output on the first night of oviposition, likely contributed to rapid field establishment of N. conspurcatalis compared with A. camptozonale.

  4. Influence of Temperature, Humidity, and Plant Terpenoid Profiles on Life History Characteristics of Boreioglycaspis melaleucae (Hemiptera: Psyllidae), a Biological Control Agent of the Invasive Tree Melaleuca quinquenervia

    Science.gov (United States)

    Although the introduced weed biological control agent Boreioglycaspis melaleucae Moore is widely established among stands of its host Melaleuca quinquenervia (Cav.) Blake (Myrtaceae) in south Florida, it’s population densities decline markedly during summer months. We investigated the hypothesis tha...

  5. A new species of Gadirtha Walker (Nolidae: Collomeninae): a proposed biological control agent of Chinese tallow (Triadica sebifera (L.) Small) (Euphorbiaceae) in the United States

    Science.gov (United States)

    Gadirtha fusca, new species, is described from Hong Kong. Adult, male and female genitalia, larva, and pupa are described, illustrated, and compared with Gadirtha impingens Walker. Species is a possible biological control agent for Chinese tallow (Triadica sebifera (L.) Small, Euphorbiaceae) in the ...

  6. Pre-release assessment of Gadirtha inexacta a proposed biological control agent of Chinese tallow (Triadica sebifera) in the United States

    Science.gov (United States)

    Native to China, Chinese tallow, Triadica sebifera (Euphorbiaceae) is an aggressive woody invader in the southeastern United States. The noctuid, Gadirtha inexacta, is a multivoltine herbivore attacking this plant in China. To evaluate its potential as a biological control agent in the United States...

  7. Description of a new species of Anagyrus Howard (Hymenoptera: Chalcidoidea: Encyrtidae), a promising biological control agent of the invasive Madeira mealybug, Phenacoccus madeirensis Green (Hemiptera: Sternorrhyncha: Pseudococcidae).

    Science.gov (United States)

    Rameshkumar, A; Noyes, J S; Poorani, J; Chong, J H

    2013-01-01

    Anagyrus amnestos sp. n. (Hymenoptera: Encyrtidae), a promising parasitoid of the invasive Madeira mealybug, Phenacoccus madeirensis Green (Hemiptera: Pseudococcidae), is described based on material collected from India. This parasitoid was identified as Anagyrus sp. nov. nr. sinope Noyes & Menezes in recent literature, and was initially collected in Georgia, USA. It was found to be a specific parasitoid of the Madeira mealybug and its biological attributes and potential as a biological control agent of this pest were studied. In what appears to be a case of fortuitous introduction, we detected this parasitoid in large numbers on Madeira mealybugs from the southern Indian state of Karnataka, where the mealybug is a recently introduced invasive pest. In view of its economic importance as a potential biological control agent of the Madeira mealybug, it is formally described and illustrated here. Comparative accounts of the new species vis-a-vis its close relatives in India and the Americas are provided.

  8. Biological agents in polyarticular juvenile idiopathic arthritis

    DEFF Research Database (Denmark)

    Amarilyo, Gil; Tarp, Simon; Foeldvari, Ivan

    2016-01-01

    BACKGROUND AND OBJECTIVE: Although various biological agents are in use for polyarticular juvenile idiopathic arthritis (pJIA), head-to-head trials comparing the efficacy and safety among them are lacking. We aimed to compare the efficacy and safety of biological agents in pJIA using all currentl...

  9. Differential performance of tropical soda apple and its biological control agent Gratiana boliviana (Coleoptera: Chrysomelidae) in open and shaded habitats

    Science.gov (United States)

    The leaf feeding beetle Gratiana boliviana Spaeth has been released since 2003 in the southeastern United States for biological control of tropical soda apple, Solanum viarum Dunal. In Florida, G. boliviana can be found on tropical soda apple growing in open pastures as well as in shady wooded areas...

  10. Release and distribution of Lilioceris cheni (Coleoptera: Chrysomelidae), a biological control agent of air potato (Dioscorea bulbilfera: Dioscoreaceae), in Florida

    Science.gov (United States)

    From 2012 to 2015, 429,668 Lilioceris cheni Gressit and Kimoto (Coleoptera: Chrysomelidae) were released in Florida for biological control of air potato [Dioscorea bulbilfera L. (Dioscoreaceae)]. The spatial distribution of releases was highly aggregated, with several areas of high density releases ...

  11. A new species of Gadirtha Walker (Nolidae, Eligminae: a proposed biological control agent of Chinese tallow (Triadica sebifera (L. Small (Euphorbiaceae in the United States

    Directory of Open Access Journals (Sweden)

    Michael Pogue

    2014-02-01

    Full Text Available Gadirtha fusca sp. n., is described from Guangxi Province, China. Gadirtha fusca differs in forewing color and pattern, male and female genitalia, and in larval pattern from all other species of Gadirtha. Gadirtha fusca has been evaluated as a potential biological control agent for Chinese tallow (Triadica sebifera (L. Small, Euphorbiaceae in the southeastern United States. Adult, male and female genitalia, larva, and pupa are described, illustrated, and compared with Gadirtha impingens Walker.

  12. A new species of Gadirtha Walker (Nolidae, Eligminae): a proposed biological control agent of Chinese tallow (Triadica sebifera (L.) Small) (Euphorbiaceae) in the United States.

    Science.gov (United States)

    Pogue, Michael G

    2014-01-01

    Gadirtha fusca sp. n., is described from Guangxi Province, China. Gadirtha fusca differs in forewing color and pattern, male and female genitalia, and in larval pattern from all other species of Gadirtha. Gadirtha fusca has been evaluated as a potential biological control agent for Chinese tallow (Triadica sebifera (L.) Small, Euphorbiaceae) in the southeastern United States. Adult, male and female genitalia, larva, and pupa are described, illustrated, and compared with Gadirtha impingens Walker.

  13. Biology and host range of Tecmessa elegans (Lepidoptera:Notodontidae) a leaf-feeding moth evaluated as a potential biological control agent for Schinus terebinthifolius (Sapindales: Anacardiaceae) in the USA

    Science.gov (United States)

    During surveys for natural enemies that could potentially be used as classical biological control agents of Schinus terebinthifolius Raddi (Brazilian pepper) which is invasive in the USA, the caterpillar, Tecmessa elegans Schaus (Lepidoptera: Notodontidae), was recorded feeding on the leaves of the ...

  14. Biological control agent of larger black flour beetles (Coleoptera: Tenebrionidae): a nuisance pest developing in cotton gin trash piles.

    Science.gov (United States)

    Nansen, Christian; Stokes, Bryan; James, Jacob; Porter, Patrick; Shields, Eilson J; Wheeler, Terry; Meikle, William G

    2013-04-01

    The larger black flour beetles, Cynaeus angustus (LeConte) (Coleoptera: Tenebrionidae), feeds on saprophytic fungi found in gin trash piles and occasionally becomes a nuisance pest in adjacent homes and businesses. The potential of Steinernema carpocapsae 'NY 001,' as a potential control agent of larger black flour beetle under experimental conditions was examined with particular reference to the importance of soil moisture content. Without prospects of insecticides being labeled for control of larger black flour beetle in gin trash, the data presented here support further research into applications of entomopathogenic nematodes underneath gin trash piles as a way to minimize risk of larger black flour beetle populations causing nuisance to nearby homes and businesses.

  15. Vaccines against biologic agents: uses and developments.

    Science.gov (United States)

    Ales, Noel C; Katial, Rohit K

    2004-03-01

    Although the Geneva protocol that prohibits the use of chemical and biologic weapons was ratified in 1925, many countries failed to accept this protocol: others stipulated retaliation, and some, like the United States, did not ratify the protocol for decades. This delay allowed the continued development of chemical and biologic agents. Members of the health care community are responsible for determining the best way to protect society from the potentially devastating effects of these biologic agents. Ideally,these diseases would be prevented from ever developing into systemic illnesses. In the past, vaccination has been a successful means of eradicating disease. Vaccines remain a hopeful therapy for the future, but time is short,and there are many obstacles.Information regarding bioterrorism agents and their treatments comes mainly from dated data or from in vitro or animal studies that may not apply to human treatment and disease. Additionally, the current threat of bioterrorism does not allow enough time for accurate, well-designed,controlled studies in humans before the release of investigational vaccines. Furthermore, some human studies would not be safe or ethical. Finally,many members of society suffer from illnesses that would put them at high risk to receive prophylactic vaccination. It is therefore naive to believe that vaccines would be the ultimate protection from these agents. In addition to vaccine development, there must be concurrent investigations into disease management and treatment. Even in instances in which vaccination is known to be an effective means of disease protection. biologic agents may be presented in a manner that renders vaccines ineffective. Virulent strains of organisms may be used, more than one organism may be used in tandem to increase virulence, and strains may be selected for antibiotic and vaccine resistance. Genetically engineered strains may use virulence factors other than those targeted in vaccines, and high

  16. Biological control of ticks

    Science.gov (United States)

    Samish, M.; Ginsberg, H.; Glazer, I.; Bowman, A.S.; Nuttall, P.

    2004-01-01

    Ticks have numerous natural enemies, but only a few species have been evaluated as tick biocontrol agents (BCAs). Some laboratory results suggest that several bacteria are pathogenic to ticks, but their mode of action and their potential value as biocontrol agents remain to be determined. The most promising entomopathogenic fungi appear to be Metarhizium anisopliae and Beauveria bassiana, strains of which are already commercially available for the control of some pests. Development of effective formulations is critical for tick management. Entomopathogenic nematodes that are pathogenic to ticks can potentially control ticks, but improved formulations and selection of novel nematode strains are needed. Parasitoid wasps of the genus Ixodiphagus do not typically control ticks under natural conditions, but inundative releases show potential value. Most predators of ticks are generalists, with a limited potential for tick management (one possible exception is oxpeckers in Africa). Biological control is likely to play a substantial role in future IPM programmes for ticks because of the diversity of taxa that show high potential as tick BCAs. Considerable research is required to select appropriate strains, develop them as BCAs, establish their effectiveness, and devise production strategies to bring them to practical use.

  17. Biologic Agents in Inflammatory Eye Disease

    OpenAIRE

    Chiara Posarelli; Ilir Arapi; Michele Figus; Piergiorgio Neri

    2011-01-01

    Non-infectious uveitis is a potentially sight threatening disease. Along the years, several therapeutic strategies have been proposed as a means to its treatment, including local and systemic steroids, immunosuppressives and more recently, biologic agents. The introduction of biologics can be defined as a new era: biologic therapies provide new options for patients with refractory and sight threatening inflammatory disorders. The availability of such novel treatment modalities has markedly im...

  18. The phylogenetic relationships of introduced Aphelinus (Hymenoptera: Aphelinidae), biological control agents of the Russian wheat aphid (Homoptera: Aphididae)

    Institute of Scientific and Technical Information of China (English)

    Yu Cheng Zhu; Quentin Q.Fang

    2009-01-01

    Several species of Aphelinus have been introduced to the US from the Old World for biological control of the Russian wheat aphid, Diuraphis noxia (Modvilko). Reproductive incompatibility has been observed among populations collected from different geographic areas. We examined whether or not the reproductive incompatibility between strains of A. asychis was caused by distant phylogenetic relationships. Ribosomal DNA sequences of internal transcribed spacers 2 (ITS2) were analyzed in several species of Aphelinus collected from multiple sites of Europe and Asia. The phylogenetic analysis showed that strains within the species A. albipodus and A. asychis are not monophyletic, and two clearly divergent clades were revealed among sequenced samples. Our results suggest that the reproductive incompatibility between three exotic strains ofA. asychis was more likely caused by divergence of phylogeny than by symbiotic bacteria.

  19. Delphastus catalinae and Coleomegilla maculata lengi (Coleoptera: Coccinellidae) as biological control agents of the greenhouse whitefly, trialeurodes vaporariorum (Homoptera: Aleyrodidae).

    Science.gov (United States)

    Lucas, Eric; Labrecque, Claude; Coderre, Daniel

    2004-11-01

    Predation efficacy and compatibility of the predatory lady beetles Coleomegilla maculata lengi Timberlake and Delphastus catalinae (Horn) against the greenhouse whitefly, Trialeurodes vaporariorum (Westwood) were studied in laboratory on glabrous fuchsia (Fuchsia hybrida Voss cv Lena Corolla) and pubescent poinsettia plants (Euphorbia pulcherrima Willd ex Klotzch cv Dark Red Annette Hegg). On glabrous plants (fuchsia), fourth-instar and adults of C maculata were the most efficient, both against whitefly eggs and pupae. On pubescent plants (poinsettia), the larger stages of C maculata were negatively affected and less efficient than adults of D catalinae. The presence of plant structure did not affect the voracity of either predator species. Finally, the simultaneous use of both predator species generated inter-specific competition. These results provide recommendations for biological control of whitefly in horticultural greenhouses.

  20. Cytotoxicity against insect cells of entomopathogenic fungi of the genera Hypocrella (anamorph Aschersonia): possible agents for biological control.

    Science.gov (United States)

    Watts, Patricia; Kittakoop, Prasat; Veeranondha, Sukitaya; Wanasith, Supakit; Thongwichian, Rossukon; Saisaha, Pattama; Intamas, Suthichai; Hywel-Jones, Nigel L

    2003-05-01

    Extracts from entomopathogenic fungi of the genus Hypocrella (7 species) and its anamorph Aschersonia (11 species) were screened for cytotoxicity to Sf9 and C6/36 insect cells and L929, BHK(21)C13 and HepG2 mammalian cells. Cytotoxic extracts to insect cells (ID50's or = 10 microg ml(-1)) conformed to the criteria of the project and were considered 'lead' extracts for further investigation. 'Leads' were found in two of the Hypocrella species: H. discoidea, and H. tamurai and in three of the Aschersonia species: A. samoensis, A. badia, and A. tamurai. Bioassay-guided fractionation of the cell extract of the fungus A. samoensis BCC 1393 led to the identification of two known anthraquinone dimers, (+)rugulosin (1) and skyrin (2) which showed selective toxicity towards insect cells. (+)Rugulosin (1) and skyrin (2) exhibited strong cytotoxic activity against the insect cell line Sf9 with respective ID50 values of 1.2 and 9.6 microg ml(-1), but showed weak activity toward mammalian cells. This first report of (+)rugulosin (1) and skyrin (2) in A. samoensis is confirmed and demonstrated in another four strains of A. samoensis isolated in Thailand. The preferential cytotoxicity against Sf9 insect cells gives evidence that these insect-pathogenic fungi of the Hypocrella/Aschersonia group might be useful as an agent for pest control.

  1. An evaluation of the wilt-causing bacterium Ralstonia solanacearum as a potential biological control agent for the alien Kahili ginger (Hedychium gardnerianum) in Hawaiian forests

    Science.gov (United States)

    1999-01-01

    Kahili ginger (Hedychium gardnerianum) is an invasive weed in tropical forests in Hawaii and elsewhere. Bacterial wilt caused by the ginger strain of Ralstonia(=Pseudomonas) solanacearum systemically infects edible ginger (Zingiber officinale) and ornamental gingers (Hedychium spp.), causing wilt in infected plants. The suitability of R. solanacearum as a biological control agent for kahili ginger was investigated by inoculating seedlings and rooted cuttings of native forest plants, ornamental ginger, and solanaceous species to confirm host specificity. Inoculation via stem injection or root wounding with a bacterial–water suspension was followed by observation for 8 weeks. Inoculations on H. gardnerianum were then carried out in ohia-lehua (Metrosideros polymorpha) wet forests of Hawaii Volcanoes National Park to determine the bacterium's efficacy in the field. No native forest or solanaceous species developed wilt or other symptoms during the study. The bacterium caused limited infection near the inoculation site on H. coronarium, Z. zerumbet, Heliconia latispatha, and Musa sapientum. However, infection did not become systemic in any of these species, and normal growth resumed following appearance of initial symptoms. All inoculated H. gardnerianum plants developed irreversible chlorosis and severe wilting 3–4 weeks following inoculation. Systemic infection also caused death and decay of rhizomes. Most plants were completely dead 16–20 weeks following inoculation. The destructiveness of the ginger strain of R. solanacearum to edible ginger has raised questions regarding its use for biological control. However, because locations of kahili ginger infestations are often remote, the risk of contaminating edible ginger plantings is unlikely. The ability of this bacterium to cause severe disease in H. gardnerianum in the field, together with its lack of virulence in other ginger species, contributes to its potential as a biological control agent.

  2. Evaluation of cellulose substrates treated with Metarhizium anisopliae (Metschnikoff Sorokin as a biological control agent against the termite Microcerotermes diversus Silvestri (Isoptera: Termitidae

    Directory of Open Access Journals (Sweden)

    Behzad Habibpour

    2011-08-01

    Full Text Available This article is the first report on the promising effect of an entomopathogenic fungus, Metarhizium anisopliae (Metschnikoff Sorokin to control populations of Microcerotermes diversus Silvestri. Biological control is an alternative to the long-term usage of chemical pesticides. M. anisopliae, the causal agent of green muscardine disease of insects, is an important fungus in biological control of insect pests. Bait systems can eliminate entire colonies of subterranean termites. Baiting reduces adverse environmental impacts caused by organochlorine and organophosphate pesticides in the control of termites and creates sustainable protection of buildings against their invasion. Treated-sawdust bait was applied by two methods: a combination of treated sawdust and untreated filter paper, and b combination of treated sawdust and untreated sawdust. When combinations of treated sawdust and untreated sawdust were used, LC50 and LC90 were 8.4×106 and 3.9×107 (spore/ml, respectively. With the use of improved bait formula and more virulent strains, we hope to achieve better control of termite colonies and enable pathogens to become a useful element in the Integrated Pest Management system.

  3. Psoriatic arthritis: treatment strategies using biologic agents

    Directory of Open Access Journals (Sweden)

    C. Palazzi

    2012-06-01

    Full Text Available The traditional management of psoriatic arthritis (PsA includes NSAIDs, corticosteroids and DMARDs. Advancement in the knowledge of the immunopathogenesis of PsA has been associated with the development of biologic agents which have revolutionized the management of the disease. Among biologics drugs, there are the 4 currently availablee anti-TNFα blocking agents (etanercept, infliximab, adalimumab and golimumab which are more effective than traditional DMARDs on symptoms/signs of inflammation, quality of life, function, and in inhibiting the progression of the structural joint damage. Despite of the high cost, TNF inhibitors are costeffective on both the musculoskeletal and skin manifestations of psoriatic disease.

  4. Dispersal of Dactylopius opuntiae Cockerell (Homoptera: Dactylopiidae, a biological control agent of Opuntia stricta (Haworth. Haworth. (Cactaceae in the Kruger National Park

    Directory of Open Access Journals (Sweden)

    L.C. Foxcroft

    2000-07-01

    Full Text Available Chemical control efforts, the introduction of Cactoblastis cactorum and attempted releases of Dactylopius opuntiae Cockerell into the expanding infestation of Opuntia stricta in the Skukuza region of the Kruger National Park (KNP have had limited suc- cess in preventing the spread and densification of 0. stricta. To boost the biological control component, a new strain of D. opuntiae was introduced into KNP during 1997. The new strain established readily and has destroyed large clumps of plants in the vicin- ity of the release site. A large-scale redistribution programme with D. opuntiae is now needed to exploit this biological control agent to the full. In order to match the frequency of manual releases with the natural rates of spread of the insects, surveys were conducted under field conditions to determine the dispersal abilities ofD. opuntiae, with regard to rate and direction of movement. Dispersal of D. opuntiae was found to be slow and restricted and that the insects need to be redistributed by placing them onto plants at approximately 10 m intervals to ensure that they become quickly and evenly distributed on the weed. This information will be crucial in the revision of the integrated management plan for 0. stricta in the KNP, in integrating the cochineal and other control mechanisms.

  5. Biology and host range of Tecmessa elegans (Lepidoptera: Notodontidae), a leaf-feeding moth evaluated as a potential biological control agent for Schinus terebinthifolius (Sapindales: Anacardiaceae) in the United States.

    Science.gov (United States)

    Oleiro, Marina; Mc Kay, Fernando; Wheeler, Gregory S

    2011-06-01

    During surveys for natural enemies that could be used as classical biological control agents of Schinus terebinthifolius Raddi (Brazilian pepper), the caterpillar, Tecmessa elegans Schaus (Lepidoptera: Notodontidae), was recorded feeding on the leaves of the shrub in South America. The biology and larval and adult host range of this species were examined to determine the insect's suitability for biological control of this invasive weed in North America and Hawaii. Biological observations indicate that the larvae have five instars. When disturbed, the late instar larvae emit formic acid from a prothoracic gland that may protect larvae from generalist predators. Larval host range tests conducted both in South and North America indicated that this species feeds and completes development primarily on members of the Anacardiaceae within the tribe Rhoeae. Oviposition tests indicated that when given a choice in large cages the adults will select the target weed over Pistacia spp. However, considering the many valued plant species in its host range, especially several North American natives, this species will not be considered further for biological control of S. terebinthifolius in North America.

  6. Cyprinid herpesvirus 3 as a potential biological control agent for carp (Cyprinus carpio) in Australia: susceptibility of non-target species.

    Science.gov (United States)

    McColl, K A; Sunarto, A; Slater, J; Bell, K; Asmus, M; Fulton, W; Hall, K; Brown, P; Gilligan, D; Hoad, J; Williams, L M; Crane, M St J

    2016-12-27

    Carp (Cyprinus carpio L.) is a pest species in Australian waterways, and cyprinid herpesvirus 3 (CyHV-3) is being considered as a potential biological control (biocontrol) agent. An important consideration for any such agent is its target specificity. In this study, the susceptibility to CyHV-3 of a range of non-target species (NTS) was tested. The NTS were as follows: 13 native Australian, and one introduced, fish species; a lamprey species; a crustacean; two native amphibian species (tadpole and mature stages); two native reptilian species; chickens; and laboratory mice. Animals were exposed to 100-1000 times the approximate minimum amount of CyHV-3 required to cause disease in carp by intraperitoneal and/or bath challenge, and then examined clinically each day over the course of 28 days post-challenge. There were no clinical signs, mortalities or histological evidence consistent with a viral infection in a wide taxonomic range of NTS. Furthermore, there was no molecular evidence of infection with CyHV-3, and, in particular, all RT-PCRs for viral mRNA were negative. As a consequence, the results encourage further investigation of CyHV-3 as a potential biocontrol agent that is specific for carp.

  7. [Decontamination of chemical and biological warfare agents].

    Science.gov (United States)

    Seto, Yasuo

    2009-01-01

    Chemical and biological warfare agents (CBWA's) are diverse in nature; volatile acute low-molecular-weight toxic compounds, chemical warfare agents (CWA's, gaseous choking and blood agents, volatile nerve gases and blister agents, nonvolatile vomit agents and lacrymators), biological toxins (nonvolatile low-molecular-weight toxins, proteinous toxins) and microbes (bacteria, viruses, rickettsiae). In the consequence management against chemical and biological terrorism, speedy decontamination of victims, facilities and equipment is required for the minimization of the damage. In the present situation, washing victims and contaminated materials with large volumes of water is the basic way, and additionally hypochlorite salt solution is used for decomposition of CWA's. However, it still remains unsolved how to dispose large volumes of waste water, and the decontamination reagents have serious limitation of high toxicity, despoiling nature against the environments, long finishing time and non-durability in effective decontamination. Namely, the existing decontamination system is not effective, nonspecifically affecting the surrounding non-target materials. Therefore, it is the urgent matter to build up the usable decontamination system surpassing the present technologies. The symposiast presents the on-going joint project of research and development of the novel decontamination system against CBWA's, in the purpose of realizing nontoxic, fast, specific, effective and economical terrorism on-site decontamination. The projects consists of (1) establishment of the decontamination evaluation methods and verification of the existing technologies and adaptation of bacterial organophosphorus hydrolase, (2) development of adsorptive elimination technologies using molecular recognition tools, and (4) development of deactivation technologies using photocatalysis.

  8. The effect of the combination of two biological control agents, Mirabilis jalapa and Bacillus thuringiensis, to Spodoptera litura's immune response and their mortality

    Science.gov (United States)

    Maulina, Dina; Anggraeni, Tjandra

    2014-03-01

    Biological control provides a safer alternative to reduce the population of agricultural pest. Mirabilis jalapa is one of many promising biopesticides which contains chemical substances that have a feeding deterrent property against insects. This biopesticide may not kill insect directly but will weaken their overall physiological condition. In this study, we investigated the immune response of common pestSpodoptera litura after exposure of M. jalapa extract. We also used Bacillus thuringiensis (Bt) delta endotoxin (LC50) on 3 hours after exposure of M. jalapa extract to see the synergism properties of both biopesticide agents. Microscopic observation revealed that at least 5 types of haemocyte were found in S. litura. In control group, plasmatocyte were found at 59.98%, prohaemocyte 20.73%, granullar cell 12.74%, oenocytoid 3.33% and spherule cell 3.20%. These proportion was differ significantly in the treatment group. Exposure to 0.1% and 0.2%(w/v) of M. jalapa extract increased the total number of haemocytes as much as 38.08% and 64.15% respectively. In contrast, exposure to 0.4% and 0.8%(w/v) reduced the number of haemocytes to 37.02% and 51.04% respectively. In term of phagocytic activity, the proportion of phagocytosing cells were 47.62% in control group, and in 0.1% and 0.2% (w/v) M. jalapa treatment group the proportion decreased to 28% and 26.88% respectively. In the concentration of 0.4% and 0.8%, phagocytic activity did not occur. Addition of biological agents Bt (LC50 concentration) to see mortality 3 hours after M. jalapa application did not show significant differences. S. litura mortality rate were found only 50%; this suggests that the combination of M. jalapa and Bt biopesticides in 3-hour intervals within 24 hours showed no increase in mortality.

  9. Diversity of endophytic fungal community of cacao (Theobroma cacao L. and biological control of Crinipellis perniciosa, causal agent of Witches' Broom Disease

    Directory of Open Access Journals (Sweden)

    2005-02-01

    Full Text Available The basidiomycete fungus Crinipellis perniciosa (Stahel Singer is the causal agent of Witches' Broom Disease of Cacao (Theobroma cacao L. which is the main factor limiting cacao production in the Americas. Pod losses of up to 90% are experienced in affected areas as evidenced by the 50% drop in production in Bahia province, Brazil following the arrival of the C. perniciosa in the area in 1989. The disease has proven particularly difficult to control and many farmers in affected areas have given up cacao cultivation. In order to evaluate the potential of endophytes as a biological control agent of this phytopathogen, the endophytic fungal community of resistant and susceptible cacao plants as well as affected branches was studied between 2001 and 2002. The fungal community was identified by morphological traits and rDNA sequencing as belonging to the genera Acremonium, Blastomyces, Botryosphaeria, Cladosporium, Colletotrichum, Cordyceps, Diaporthe, Fusarium, Geotrichum, Gibberella, Gliocladium, Lasiodiplodia, Monilochoetes, Nectria, Pestalotiopsis, Phomopsis, Pleurotus, Pseudofusarium, Rhizopycnis, Syncephalastrum, Trichoderma, Verticillium and Xylaria. These fungi were evaluated both in vitro and in vivo by their ability to inhibit C. perniciosa. Among these, some were identified as potential antagonists, but only one fungus (Gliocladium catenulatum reduced the incidence of Witches' Broom Disease in cacao seedlings to 70%.

  10. Potential Use of Entomopathogenic Virus Native to Sumatra Island as Biological Control Agent of Setora nitens L. (Lepidoptera:Limacodidae, the Main Pest of Oilpalm

    Directory of Open Access Journals (Sweden)

    Suparman Suparman

    2013-01-01

    Full Text Available Slug caterpillars Setora nitens, have been appearing to be more serious insect pest of oil palm as it might cause frond damages up to 90%. Many effort had been made to control the caterpillars using insecticides but the insects are still existing and causing significant damages to the palm. Microbial insecticide, especially the one developed from indigenous entomopathogenic virus, is a promising method of controlling the insect since its toxicity to non target animals and humans is extremely low. A conventional way of controlling S. nitens using crude sap of infected larvae has been applied in several oil palm plantations in Sumatra Island, but various improvements are required to make the method more effective, efficient, widely acceptable and scientifically justified. A research on the potential use of entomopathogenic virus native to Sumatra Island as biological control agent of slug caterpillar was conducted to comprehend the pathogenicity and virulence of the entomopathogenic virus and to reveal the morphological identify of its particle. The results showed that the use of virus infecting caterpillars to control the insect was quite successful in term of increasing the number of infected caterpillars and reducing the rate of population development in the field. The use of homogenized infected caterpillars to orally infect healty S. nitens caterpillars resulted in the symptoms characteristics to viral infections appeared in all treated caterpillars with various extent of symptom developments. Some caterpillars could spine cocons but failed to release adult moth. Purification of the virus particles from infected caterpillars resulted in the apperarance of white band in the sucrose gradient indicated the presence of viral RNA. Electron microscopic observation showed that the white band in the sucrose gradient contained sphericle shape of virus particles justifying that the agent infecting S. nitens caterpillars is a virus which still need

  11. Patient Adherence to Biologic Agents in Psoriasis

    DEFF Research Database (Denmark)

    Hsu, Der Yi; Gniadecki, Robert

    2016-01-01

    BACKGROUND: Low adherence to therapies in psoriasis decreases treatment outcomes and increases the total health care costs. In spite of the wide use of biologic agents, patients' adherence to these drugs has not been extensively investigated. OBJECTIVE: The aim of this study is to measure adherence...... adverse effects, and positive attitudes to the treatment. CONCLUSION: Adherence to biologic therapies is very high in patients with psoriasis, which is consistent with a positive attitude to the treatment....... to the biologic drugs in a population of patients treated for psoriasis vulgaris using the medication possession ratio (MPR) index and to survey patients' attitudes to the treatment. METHODS: This is a single-center study on 247 patients with psoriasis vulgaris treated with adalimumab (n = 113), etanercept (n...

  12. Coccophagus scutellaris (Hymenoptera: Aphelinidae): A Highly Effective Biological Control Agent of Soft Scale Insects (Hemiptera: Coccidae) in Egypt

    OpenAIRE

    Shaaban Abd-Rabou

    2011-01-01

    About 953000 individuals of the cosmopolitan parasitoid, Coccophagus scutellaris (Dalman) (Hymenoptera: Aphelinidae), were released and evaluated during 2009-2010 for the control of the following soft scale insects (Hemiptera: Coccidae) infesting the following economic crops in Egypt: Ceroplastes rusci on citrus in Beni Seuf, Ceroplastes floridensis Comstock on citrus in Gharbiya, Coccus hesperidum L. on guava in Giza, Pulvinaria floccifera (Westwood) on mango in Sharqiya, Pulvinaria psidii...

  13. Biological agents targeting beyond TNF-alpha

    Science.gov (United States)

    Sharma, Rashmi; Sharma, Chaman Lal; Mahajan, Annil

    2008-01-01

    Biological agents represent an important addition to the therapies for immuno-inflammatory conditions and have a great impact on the disease course and quality of life of these patients. However, recent reports of serious infections like tuberculosis, demyelinating and neurodegenerative diseases, pancytopenia, cardiovascular diseases, etc. after anti-TNF therapy raised questions on their safety. Hence, focus is shifted towards drugs targeting cytokine checkpoints in the inflammatory cascades beyond TNF-α. Existing therapeutic targets include the biological agents acting as antagonists of various inflammatory cytokines (Anakinra, Tocilizumab, Atlizumab) and modulators of CD80 or CD86-CD28 co-stimulatory signal (Abatacept), CD2 receptors on T-cells (Alefacept), CD11a, subunit of leukocyte function-associated antigen 1 (Efalizumab), vitronectin receptor and CD20 antigen on pre-B, immature and mature B cells (Rituximab). With the introduction of these novel molecules the future for immunomodulatory intervention in rheumatology, asthma, crohn's disease, septic shock etc. looks very promising. These novel therapeutic agents could truly give a new hope to the clinician to modify the disease and achieve tangible improvements in the lives of the patients. PMID:19742267

  14. Biological agents targeting beyond TNF-alpha

    Directory of Open Access Journals (Sweden)

    Sharma Rashmi

    2008-01-01

    Full Text Available Biological agents represent an important addition to the therapies for immuno-inflammatory conditions and have a great impact on the disease course and quality of life of these patients. However, recent reports of serious infections like tuberculosis, demyelinating and neurodegenerative diseases, pancytopenia, cardiovascular diseases, etc. after anti-TNF therapy raised questions on their safety. Hence, focus is shifted towards drugs targeting cytokine checkpoints in the inflammatory cascades beyond TNF-a. Existing therapeutic targets include the biological agents acting as antagonists of various inflammatory cytokines (Anakinra, Tocilizumab, Atlizumab and modulators of CD80 or CD86-CD28 co-stimulatory signal (Abatacept, CD2 receptors on T-cells (Alefacept, CD11a, subunit of leukocyte function-associated antigen 1 (Efalizumab, vitronectin receptor and CD20 antigen on pre-B, immature and mature B cells (Rituximab. With the introduction of these novel molecules the future for immunomodulatory intervention in rheumatology, asthma, crohn′s disease, septic shock etc. looks very promising. These novel therapeutic agents could truly give a new hope to the clinician to modify the disease and achieve tangible improvements in the lives of the patients.

  15. Effect of biologic agents on radiographic progression of rheumatoid arthritis

    Directory of Open Access Journals (Sweden)

    Gabriel J Tobón

    2010-08-01

    Full Text Available Gabriel J Tobón1, Alain Saraux1,2, Valérie Devauchelle-Pensec1,21Immunology Laboratory, Morvan Hospital, Université de Bretagne Occidentale, Brest, France; 2Rheumatology Unit, Hôpital de la Cavale Blanche, CHU Brest, FranceAbstract: The treatment of rheumatoid arthritis (RA has benefited over the last few years from the introduction of biologic agents whose development was based on new insights into the immunological factors involved in the pathogenesis of RA and the development of joint damage. These biological agents have been proven effective in RA patients with inadequate responses to synthetic disease-modifying antirheumatic drugs (DMARDs. Preventing joint damage is now the primary goal of RA treatment, and guidelines exist for the follow-up of joint abnormalities. Most biologic agents produced high clinical and radiological response rates in patients with established or recent-onset RA. Thus, for the first time, obtaining a remission is a reasonable treatment goal in RA patients. Factors that are crucial to joint damage control are: early initiation of DMARDs, use of intensive treatments including biological agents, and close monitoring of clinical disease activity and radiographic progression. However, some patients remain unresponsive to all available treatments and continue to experience joint damage progression. A major objective now is to identify patients at high risk for severe joint damage, in order to tailor the treatment regimen to their specific needs.Keywords: rheumatoid arthritis, radiographic progression, biologics

  16. Fungi colonizing the soil and roots of tomato (Lycopersicum esculentum Mill. plants treated with biological control agents

    Directory of Open Access Journals (Sweden)

    Bożena Cwalina-Ambroziak

    2012-12-01

    Full Text Available Tomato plants, cv. Rumba Ożarowska, grown in the greenhouse of the University of Warmia and Mazury, were protected in the form of alternate spraying (twice and watering (twice with 5% aqueous extracts of the following plant species: Aloe vulgaris Lam., Achillea millefolium L., Mentha piperita L., Polygonum aviculare L., Equisetum arvense L., Juglans regia L. and Urtica dioica L. Plants not treated with the extracts served as control. After fruit harvest, samples of roots and soil were collected. The roots were disinfected and next placed on PDA medium. Soil-colonizing fungi were cultured on Martin medium. Fungi were identified microscopically after incubation. Pathogenic fungal species, Colletotrichum coccodes, Fusarium equiseti, F. oxysporum and F. poae, accounted for over 60% of all isolates obtained from the roots of tomato plants. The soil fungal community was dominated by yeast-like fungi (75.4%, whereas pathogenic fungi were present in low numbers. The applied 5% aqueous plant extracts effectively reduced the abundance of fungi, including pathogenic species, colonizing tomato plants and soil. The extract from P. aviculare showed the highest efficacy, while the extract from J. regia was least effective. Fungi showing antagonistic activity against pathogens (Paecilomyces roseum and species of the genus Trichoderma were isolated in greatest abundance from the soil and the roots of tomato plants treated with A. millefolium, M. piperita and U. dioica extracts.

  17. Potential of Entomopathogenic Fungi as Biological Control Agents of Diamondback Moth (Lepidoptera: Plutellidae) and Compatibility With Chemical Insecticides.

    Science.gov (United States)

    Duarte, R T; Gonçalves, K C; Espinosa, D J L; Moreira, L F; De Bortoli, S A; Humber, R A; Polanczyk, R A

    2016-04-01

    The objectives were to evaluate the efficiency of entomopathogenic fungi against Plutella xylostella (L.) and the compatibility of the most virulent isolates with some of the insecticides registered for use on cabbage crops. Pathogenicity tests used isolates of Beauveria bassiana, Metarhizium rileyi, Isaria fumosorosea, Isaria sinclairii, and Lecanicillium muscarium standardized at a concentration of 10(7) conidia/ml. Cabbage leaf discs were immersed in these suspensions, and after evaporation of the excess water, were placed 10 second-instar larvae of P. xylostella, totaling 10 leaf discs per treatment. Mortality was assessed 7 d after treatment, and the isolates that caused mortality>80% were used to estimate LC50 and LT50. The compatibilities of the most virulent isolates and the insecticides were tested from the mixture of these into the culture medium, and after solidifying, the medium was inoculated with an aliquot of the isolated suspension. The following parameters were evaluated: growth of the colony, number and viability of conidia after 7 d. The isolated IBCB01, IBCB18, IBCB66, and IBCB87 of B. bassiana, LCMAP101 of M. rileyi, and ARSEF7973 of I. sinclairii caused mortality between 80 and 100%, with LC50 and LT50 between 2.504 to 6.775×10(4) conidia/ml and 52.22 to 112.13 h, respectively. The active ingredients thiamethoxam and azadirachtin were compatible with the entomopathogenic fungi. The results suggest that the use of these isolates is an important alternative in the pesticidal management of P. xylostella, with the possible exception of the associated use of chemical controls using the active ingredients thiamethoxam or azadirachtin.

  18. Insecticides and Biological Control

    Science.gov (United States)

    Furness, G. O.

    1972-01-01

    Use of insecticides has been questioned due to their harmful effects on edible items. Biological control of insects along with other effective practices for checking spread of parasites on crops are discussed. (PS)

  19. Macrochelid Mite, Macrocheles muscaedomesticae (Acarina: Macrochelidae as a Biological Control Agent Against House Fly, Musca domestica (Diptera: Muscidae in Egypt

    Directory of Open Access Journals (Sweden)

    Safaa

    2014-01-01

    Full Text Available Numerous species of macrochelids (Acarina: Mesostigmata have shown capability to attack housefly larvae and eggs but it is presumed that only a few of them play a significant role in the control of flies in nature. Macrocheles muscaedomesticae (Scopoli is one of several mites that feeds on eggs, newly hatched and small larvae of house fly Musca domestica L. This study provide avidence that macrochelid mite is attacking not only housefly larvae and eggs but also on housefly adults. Macrocheles muscaedomesticae mite was reared in the laboratory on house fly frozen eggs and first instar of larvae at constant conditions of 28°C±1 and 90% relative humidity using sterilized artificial diet. The mean incubation period of eggs, total immatures, female longevity were 0.7, 4.0 and 25.2 days, respectively when fed on frozen eggs meanwhile means were 0.8, 7.0 and 22.6 days when fed on first instar larvae of M. domestica. The total consumption of female was 131.1 eggs/female or 82.7 larvae. Results of the present study showed that the mean mortality percentages of eggs due to predation of three levels of predator 2, 5 and 10 individuals were 57.2, 74.9 and 96.5 after 5, 4, 2 days, respectively. Also, the larval stage of M. domestica was introduced with three levels of 10, 20 and 25 individuals for each level of predatory mite 2, 5 and 10 adults, respectively. Results revealed that the best results were recorded at the level of 5 mites, where the mean mortality percentage of larvae was 100% after one day when introduced with 10 housefly’s larvae but it was 96% after two days when introduced with 20 housefly’s larvae and 76.2% after three days when introduced with 25 houseflies larvae at level of 5. In addition, the present study provide evidence that mites can consume the housefly adult stage. Our findings indicated that the best results were recorded at the level of 10 mites where the mean mortality percentages of adults were 83.55%, the fly died after

  20. Looming Threat of Chemical and Biological Warfare Agents

    Directory of Open Access Journals (Sweden)

    A.K. Goel

    2016-09-01

    Full Text Available In the recent past, a dramatic shift has been observed in the strategies of warfare from conventional to non-conventional. Now-a-days, traditional power is of less importance than it used to be earlier. Weapons of mass destruction, which comprise of nuclear weapons, and chemical and biological warfare agents, are posing a great peril to the world due to their devastating potential. Though, there are several bilateral as well as multilateral treaties to control the use and proliferation of these weapons, yet the risk of use of such agents by non-state actors cannot be overlooked. Chances of use of chemical and biological agents are more likely than the nuclear weapons. A comparison of nuclear, chemical and biological weapons in terms of technology, cost, signature, effectiveness on protected and un-protected troops shows that chemical and biological weapon programmes require much lower level of technology and cost than the nuclear weapon programme. Further, there is no or least distinctive and readily observable signature in biological weapon programme in comparison to nuclear and chemical weapon facilities. There can be two possibilities of use of these agents in terrorist attacks. First, there is a risk of transfer of material or know-how of these weapons to terrorists for using against the adversaries and second, the risk of these agents being pilfered due to poor security, thereby sabotaging the national security. The International Committee of Red Cross in February 1918 reckoned these agents as ‘barbarous inventions’ that can ‘only be called criminal’.

  1. The biological control of disease vectors.

    Science.gov (United States)

    Okamoto, Kenichi W; Amarasekare, Priyanga

    2012-09-21

    Vector-borne diseases are common in nature and can have a large impact on humans, livestock and crops. Biological control of vectors using natural enemies or competitors can reduce vector density and hence disease transmission. However, the indirect interactions inherent in host-vector disease systems make it difficult to use traditional pest control theory to guide biological control of disease vectors. This necessitates a conceptual framework that explicitly considers a range of indirect interactions between the host-vector disease system and the vector's biological control agent. Here we conduct a comparative analysis of the efficacy of different types of biological control agents in controlling vector-borne diseases. We report three key findings. First, highly efficient predators and parasitoids of the vector prove to be effective biological control agents, but highly virulent pathogens of the vector also require a high transmission rate to be effective. Second, biocontrol agents can successfully reduce long-term host disease incidence even though they may fail to reduce long-term vector densities. Third, inundating a host-vector disease system with a natural enemy of the vector has little or no effect on reducing disease incidence, but inundating the system with a competitor of the vector has a large effect on reducing disease incidence. The comparative framework yields predictions that are useful in developing biological control strategies for vector-borne diseases. We discuss how these predictions can inform ongoing biological control efforts for host-vector disease systems.

  2. Similar effects of disease-modifying antirheumatic drugs, glucocorticoids, and biologic agents on radiographic progression in rheumatoid arthritis: meta-analysis of 70 randomized placebo-controlled or drug-controlled studies, including 112 comparisons

    DEFF Research Database (Denmark)

    Graudal, Niels; Jürgens, Gesche

    2010-01-01

    To define the differences in effects on joint destruction in rheumatoid arthritis (RA) patients between therapy with single and combination disease-modifying antirheumatic drugs (DMARDs), glucocorticoids, and biologic agents.......To define the differences in effects on joint destruction in rheumatoid arthritis (RA) patients between therapy with single and combination disease-modifying antirheumatic drugs (DMARDs), glucocorticoids, and biologic agents....

  3. Treatment of relapsing polychondritis in the era of biological agents.

    LENUS (Irish Health Repository)

    McCarthy, Eoghan M

    2012-02-01

    Relapsing polychondritis (RP) is a rare disorder, often requiring high doses of immunosuppressive therapy to control its potentially life-threatening consequences. The advent of biological agents has added to the armamentarium available to treat RP, but the lack of controlled trials, along with the small numbers of patients and disease heterogeneity means that new therapies are prescribed without the benefits of rigorous clinical research. Thus, information on individual cases is of value in expanding our knowledge of the use of biologic agents in rare conditions. We report on the use of rituximab in a patient who subsequently developed catastrophic aortic incompetence, and we review the literature in relation to the use of this drug in RP.

  4. Possible application of a nematophagous fungus as a biological control agent of parasitic nematodes on commercial sheep farms in South Africa

    Directory of Open Access Journals (Sweden)

    M. Faedo

    2002-07-01

    Full Text Available Biological control of parasitic nematodes of livestock is currently under development and represents another tool that may be integrated into helminth parasite control strategies. This paper presents a brief introduction to commercial sheep farming in South Africa and currently available nematode parasite control methods. These include the FAMACHA(r clinical assay, strategies of pasture management, dilution of resistant worm species by introduction of susceptible worms, breed resistant sheep and nutritional supplementation. The purpose of this paper is to outline the principles of biological control using nematophagous fungi and how it may be applied on sheep farms in South Africa.

  5. Possible application of a nematophagous fungus as a biological control agent of parasitic nematodes on commercial sheep farms in South Africa.

    Science.gov (United States)

    Faedo, M; Krecek, R C

    2002-03-01

    Biological control of parasitic nematodes of livestock is currently under development and represents another tool that may be integrated into helminth parasite control strategies. This paper presents a brief introduction to commercial sheep farming in South Africa and currently available nematode parasite control methods. These include the FAMACHA clinical assay, strategies of pasture management, dilution of resistant worm species by introduction of susceptible worms, breed resistant sheep and nutritional supplementation. The purpose of this paper is to outline the principles of biological control using nematophagous fungi and how it may be applied on sheep farms in South Africa.

  6. Commercializing Biological Control

    Science.gov (United States)

    LeLeu, K. L.; Young, M. A.

    1973-01-01

    Describes the only commercial establishment involved in biological control in Australia. The wasp Aphitis melinus, which parasitizes the insect Red Scale, is bred in large numbers and released in the citrus groves where Red Scale is causing damage to the fruit. (JR)

  7. Fundamental host range of Pseudophilothrips ichini s.l. (Thysanoptera: Phlaeothripidae): a candidate biological control agent of Schinus terebinthifolius (Sapindales: Anacardiaceae) in the United States.

    Science.gov (United States)

    Cuda, J P; Medal, J C; Gillmore, J L; Habeck, D H; Pedrosa-Macedo, J H

    2009-12-01

    Schinus terebinthifolius Raddi (Sapindales: Anacardiaceae) is a non-native perennial woody plant that is one of the most invasive weeds in Florida, Hawaii, and more recently California and Texas. This plant was introduced into Florida from South America as a landscape ornamental in the late 19th century, eventually escaped cultivation, and now dominates entire ecosystems in south-central Florida. Recent DNA studies have confirmed two separate introductions of S. terebinthifolius in Florida, and there is evidence of hybridization. A thrips, Pseudophilothrips ichini s.l. (Hood) (Thysanoptera: Phlaeothripidae), is commonly found attacking shoots and flowers of S. terebinthifolius in Brazil. Immatures and occasionally adults form large aggregations on young terminal growth (stems and leaves) of the plant. Feeding damage by P. ichini s.l. frequently kills new shoots, which reduces vigor and restricts growth of S. terebinthifolius. Greenhouse and laboratory host range tests with 46 plant species in 18 families and 10 orders were conducted in Paraná, Brazil, and Florida. Results of no-choice, paired-choice, and multiple-choice tests indicated that P. ichini s.l. is capable of reproducing only on S. terebinthifolius and possibly Schinus molle L., an ornamental introduced into California from Peru that has escaped cultivation and is considered invasive. Our results showed that P. ichini s.l. posed minimal risk to mature S. molle plants or the Florida native Metopium toxiferum L. Krug and Urb. In May 2007, the federal interagency Technical Advisory Group for Biological Control Agents of Weeds (TAG) concluded P. ichini s.l. was sufficiently host specific to recommend its release from quarantine.

  8. Hyphae-colonizing Burkholderia sp.--a new source of biological control agents against sheath blight disease (Rhizoctonia solani AG1-IA) in rice.

    Science.gov (United States)

    Cuong, Nguyen Duc; Nicolaisen, Mette Haubjerg; Sørensen, Jan; Olsson, Stefan

    2011-08-01

    Sheath blight infection of rice by Rhizoctonia solani Kühn AG1-IA often results in serious yield losses in intensive rice cultivation. Biological control agents (BCAs) have previously been isolated but poor efficiency is often observed when applied under field conditions. This study compares a traditional dual-culture plate assay and a new water-surface microcosm assay for isolation of antagonistic soil bacteria. In the water-surface microcosm assay, floating pathogen mycelium is used as a source for isolation of hyphae-colonizing soil bacteria (HCSB), which are subsequently screened for antagonism. Ten antagonistic soil bacteria (ASB) isolated from a variety of Vietnamese rice soils using dual-culture plates were found to be affiliated with Bacillus based on 16S rRNA gene sequencing. However, all the ASB isolates grew poorly and showed no antagonism in the water-surface microcosm assay. In contrast, 11 (out of 13) HCSB isolates affiliated with Burkholderia sp. all grew well by colonizing the hyphae in the microcosms. Two of the Burkholderia sp. isolates, assigned to B. vietnamiensis based on recA gene sequencing, strongly inhibited fungal growth in both the dual-culture and water-surface microcosm assays; HCSB isolates affiliated to other species or species groups showed limited or no inhibition of R. solani in the microcosms. Our results suggest that HCSB obtained from floating pathogen hyphae can be a new source for isolation of efficient BCAs against R. solani, as the isolation assay mimics the natural habitat for fungal-bacterial interaction in the fields.

  9. Clinical laboratories, the select agent program, and biological surety (biosurety).

    Science.gov (United States)

    Pastel, Ross H; Demmin, Gretchen; Severson, Grant; Torres-Cruz, Rafael; Trevino, Jorge; Kelly, John; Arrison, Jay; Christman, Joy

    2006-06-01

    The threat of bioterrorism has led to increased concerns over the availability of biological select agents and toxins (BSAT). Congress has implemented several public laws that have led to the development of federal regulations by the Centers for Disease Control and Prevention (CDC) and the US Department of Agriculture. The CDC regulation 42 CFR 73 has a direct impact on all clinical laboratories that may at some time identify BSAT in a clinical specimen. The Department of Defense has imposed a more stringent layer of regulation called biological surety (biosurety) on top of the requirements of 42 CFR 73 for military laboratories that possess BSAT. However,42 CFR 73 falls into the framework of biosurety. Both sets of regulations have four pillars (safety, physical security, agent account-ability, and personnel reliability) that are built on a foundation of training and covered by a roof of management (operations and plans).

  10. Molecular comparison of cattle fever ticks from native and introduced ranges with insights into optimal search areas for classical biological control agents

    Science.gov (United States)

    Classical biological control using specialist parasitoids, predators and/or nematodes from the native ranges of cattle fever ticks could complement existing control strategies for this livestock pest in the transboundary region between Mexico and Texas. DNA fingerprinting tools were used to compare ...

  11. Effect of nitrogen fertilization on growth of Arundo donax and on rearing of a biological control agent, the shoot gall-forming wasp Tetramesa romana

    Science.gov (United States)

    Nitrogen augmentation often leads to increased feeding and/or reproduction by herbivorous insects, but little is known about the effects on insects that gall grasses. The shoot tip-galling wasp Tetramesa romana has been released for biological control of the giant grass arundo (Arundo donax) in the...

  12. Assessing non-target effects and host feeding of the exotic parasitoid Apanteles taragamae, a potential biological control agent of the cowpea pod borer Maruca vitrata

    NARCIS (Netherlands)

    Dannon, A.E.; Tamo, M.; Huis, van A.; Dicke, M.

    2012-01-01

    Apanteles taragamae Viereck is a larval parasitoid introduced in Benin for classical biological control of the cowpea pod borer Maruca vitrata Fabricius. In the laboratory, we evaluated the effects of A. taragamae on non-target herbivore species, and on another parasitoid of M. vitrata, i.e. the egg

  13. Releases, distribution and abundance of Gratiana boliviana (Coleoptera:Chrysomelidae), a biological control agent of tropical soda apple (Solanum viarum, Solanaceae), in Florida

    Science.gov (United States)

    A biological control program against tropical soda apple (TSA) (Solanum viarum Dunal (Solanaceae)) released 176,643 Gratiana boliviana Spaeth (Coleoptera: Chrysomelidae) in Florida from 2003 to 2008. The spatial distribution of releases was clustered with more beetles released in south/central Flor...

  14. Open-field host specificity test of Gratiana boliviana (Coleoptera:Chrysomelidae), a biological control agent of Tropical Soda Apple (Solanaceae) in the United States

    Science.gov (United States)

    An open-field experiment was conducted to asses the suitability of the South American leaf feeding beetle Gratiana boliviana Spaeth for biological control of Solanum viarum Dunal in the USA. An open-field test with eggplant, Solanum melongena L., was conducted on the campus of the University of Buen...

  15. The interactions of Tropical soda apple mosaic tobamovirus and Gratiana boliviana (Coleoptera: Chrysomelidae), an introduced biological control agent of tropical soda apple (Solanum viarum)

    Science.gov (United States)

    Tropical soda apple (Solanum viarum Dunal (Solanaceae) (TSA) is a South American invasive plant of rangelands, pastures and natural areas in Florida. A chrysomelid beetle from South America, Gratiana boliviana Spaeth, has been released at >300 locations in Florida for biological control of TSA since...

  16. Establishment, population increase, spread, and ecological host range of Lophodiplosis trifida (Diptera: Cecidomyiidae), a biological control agent of the invasive tree Melaleuca quinquenervia (Myrtales:Myrtaceae).

    Science.gov (United States)

    The Australian tree Melaleuca quinquenervia (Cav.) Blake is an invasive weed in wetland systems of Florida, USA. A biological control program targeting M. quinquenervia has culminated in the release of the gall forming midge Lophodiplosis trifida Gagné (Cecidomyiidae). Populations of the introduced ...

  17. Ecological Compatibility of GM Crops and Biological Control

    Science.gov (United States)

    Insect-resistant and herbicide-tolerant genetically modified (GM) crops pervade many modern cropping systems, and present challenges and opportunities for developing biologically-based pest management programs. Interactions between biological control agents (insect predators, parasitoids, and pathog...

  18. Effect of Two Biological Formulations Based on Bacillus subtilis and Pseudomonas fluorescens on Control of Didymella applanata, the Causal Agent of Red Raspberry Cane Spur Blight

    Directory of Open Access Journals (Sweden)

    Margarita Shternshis

    2016-01-01

    Full Text Available In vitro and in vivo studies were conducted to estimate the efficacy of the two microbial formulations based on Bacillus subtilis Cohn. and Pseudomonas fluorescens Mig. on the fungus Didymella applanata (Niessl. Sacc., the causal agent of red raspberry (Rubus idaeus L. spur blight. In vitro, both bacteria reduced the growth of D. applanata. In inoculation experiments with raspberry canes in two cultivars with different susceptibility to D. applanata, these antagonistic bacteria suppressed fungal development by reducing the lesions area and the number of D. applanata fruiting bodies. Field trials of two biological formulations under natural conditions showed a significant suppression of the disease. B. subtilis and P. fluorescens included in the formulations revealed antagonistic activity towards D. applanata that depended on the red raspberry cultivar and weather conditions. In all cases, B. subtilis showed better results than P. fluorescens in biocontrol of the raspberry spur blight. This study demonstrated for the first time the ability of the biocontrol agents B. subtilis and P. fluorescens to suppress red raspberry cane spur blight, a serious worldwide disease.

  19. Abundance, Genetic Diversity and Persistence of Metarhizium Spp. Fungi from Soil of Strawberry Crops and Their Potential as Biological Control Agents against the Two-Spotted Spider Mite Tetranychus urticae

    DEFF Research Database (Denmark)

    Castro, Thiago Rodriguesde

    The growing demand for strawberries has imposed challenges, especially regarding the control of pests. Many farmers report problems with reduced chemical control efficiency, probably due to selection of resistant populations of insects and mites. An alternative is the use of biological control...... using pathogenic fungi as a tool in integrated pest management. Metarhizium spp. (Hypocreales: Clavicipitaceae) are generalist entomopathogenic fungi with worldwide distribution and can cause diseases in a large number of hosts. Many studies on the development of Metarhizium as a biological control...... agent were performed, but this bulk of knowledge is in remarkable contrast to the lack of research on the fundamental ecology of Metarhizium in agroecosystems. This thesis aimed to evaluate the establishment, persistence and dispersal of these entomopathogenic fungi in strawberry crop soil...

  20. Studies on the Asian sawflies of Formosempria Takeuchi (Hymenoptera, Tenthredinidae, with notes on the suitability of F. varipes Takeuchi as a biological control agent for skunk vine, Paederia foetida L. (Rubiaceae in Florida

    Directory of Open Access Journals (Sweden)

    David Smith

    2014-09-01

    Full Text Available Formosempria Takeuchi, 1929, is distributed in southeastern Asia from Taiwan and China to Vietnam, Myanmar, and possibly northern India. Three species are included: F. crassicornis Wei & Nie, 2002, F. shanensis Malaise, 1961, and F. varipes Takeuchi, 1929 (= F. annamensis Malaise, 1961, syn. n.; = F. metallica Wei, 2003, syn. n.. Formosempria varipes was reared from larvae feeding on Paederia foetida L. (Rubiaceae in Hong Kong and was a potential biological agent for the invasive P. foetida in Florida. Larval feeding tests indicate more than one species of Paederia are suitable hosts for F. varipes and further study for use as a biological control agent in Florida is unwarranted. Descriptions and illustration of the species are given, and life history notes on F. varipes are presented.

  1. Agent-oriented modeling of the dynamics of complex biological processes I: single agent models

    NARCIS (Netherlands)

    Jonker, C.M.; Treur, J.

    2008-01-01

    In the pair of papers of which this is Part I, the agent-oriented modeling perspective to cope with biological complexity is discussed. Three levels of dynamics are distinguished and related to each other: dynamics of externally observable agent behavior, dynamics of internal agent processes, and dy

  2. Ecology and biological control of Verticillium dahliae

    NARCIS (Netherlands)

    Soesanto, L.

    2000-01-01

    The dynamics of Verticillium dahliae , the causal agent of wilt disease in many crops including potato, cotton, and olive, were investigated. Its biological control with Talaromyces flavus with or without additional Pseudomonas fluorescens was attempted. Arabidopsis thaliana was selected as a bioass

  3. Biologic agents for anterior cruciate ligament healing: A systematic review

    Science.gov (United States)

    Di Matteo, Berardo; Loibl, Markus; Andriolo, Luca; Filardo, Giuseppe; Zellner, Johannes; Koch, Matthias; Angele, Peter

    2016-01-01

    AIM To systematically review the currently available literature concerning the application of biologic agents such as platelet-rich plasma (PRP) and stem cells to promote anterior cruciate ligament (ACL) healing. METHODS A systematic review of the literature was performed on the use of biologic agents (i.e., PRP or stem cells) to favor ACL healing during reconstruction or repair. The following inclusion criteria for relevant articles were used: Clinical reports of any level of evidence, written in English language, on the use of PRP or stem cells during ACL reconstruction/repair. Exclusion criteria were articles written in other languages, reviews, or studies analyzing other applications of PRP/stem cells in knee surgery not related to promoting ACL healing. RESULTS The database search identified 394 records that were screened. A total of 23 studies were included in the final analysis: In one paper stem cells were applied for ACL healing, in one paper there was a concomitant application of PRP and stem cells, whereas in the remaining 21 papers PRP was used. Based on the ACL injury pattern, two papers investigated biologic agents in ACL partial tears whereas 21 papers in ACL reconstruction. Looking at the quality of the available literature, 17 out of 21 studies dealing with ACL reconstruction were randomized controlled trials. Both studies on ACL repair were case series. CONCLUSION There is a paucity of clinical trials investigating the role of stem cells in promoting ACL healing both in case of partial and complete tears. The role of PRP is still controversial and the only advantage emerging from the literature is related to a better graft maturation over time, without documenting beneficial effects in terms of clinical outcome, bone-graft integration and prevention of bony tunnel enlargement. PMID:27672573

  4. Bioprotective agents in safety control

    Directory of Open Access Journals (Sweden)

    Dimitrijević-Branković Suzana I.

    2003-01-01

    Full Text Available Food poisoning is the one of the main health hazards even today. More than 200 known diseases are transmitted through food. The causes of foodborne illness include viruses, bacteria, parasites, toxins, metals, and prions and the symptoms of foodborne illness range from mild gastroenteritis to life-threatening neurological, hepatic and renal syndromes.The prevention of food poisonings represents very serious task for food manufacturers. Beside food control according to the concept "from the farm to the table" there is increased need for the development of new technology for longer shelf lifes of food. Food fermented by lactic acid bacteria (LAB and traditionally considered to be safe. There are many substances produced by LAB that affect the shelf life of fermented food, by active suppression of poisoning microorganisms growth. Because of that, the LAB is recently considered as bioprotective agents that have important role in food safety.

  5. Advanced UV Source for Biological Agent Destruction

    Science.gov (United States)

    2006-01-01

    G., “ Photocatalysis Under Periodic Illumination, Ph.D. Thesis, California Institute of Technology, September 24, 2001.) 6 Wavelength (nm) 175...phosphate MDCP Methyl salicylate Figure 2.4-1. UV absorption cross sections for various chemical agents and simulants. Titanium dioxide ( TiO2 ) is one

  6. Capabilities for identification and confirmation of bacterial biological agents

    Directory of Open Access Journals (Sweden)

    Diana M. Popescu

    2016-12-01

    Full Text Available Military Medical Service is able for detection, identification and confirmation of biological agents; it is part of medical protection against CBRN weapons. We are specialized capabilities for in vitro tests, under construction, the maximum containment laboratory designed for work with Risk Group Microorganisms. An efficient primary containment system must be in place, consisting of one or a combination of the following: Class III safety cabinet laboratory, passage of two doors, suit laboratory, controlled access, controlled air system. Negative pressure in the facility, supply and exhaust air must be HEPA-filtered, decontamination of effluents, sterilization of waste and materials, airlock entry ports for specimens, materials and animals must be provided etc. Complementary is an Animal facility for in vivo tests. This is suitable for work with animals that are deliberately inoculated with microorganisms in Risk Group.

  7. The effect of the application of the biological control agent EM1 on gas exchange parameters and productivity of Pisum sativum L. infected with Fusarium oxysporum Schlecht.

    Directory of Open Access Journals (Sweden)

    Adam Okorski

    2012-12-01

    Full Text Available A pot experiment on different methods of EM 1 application was conducted in the period 2002-2004. The study was carried out under controlled growth conditions. The experimental factor was the method of EM1 application. Before application, the biological preparation EM1 was propagated as recommended by the manufacturer (Greenland. The health status of the aboveground parts of 'Ramrod' pea plants was estimated at the flowering stage. The assessment of pea leaf gas exchange parameters (An, E, Gs, and Ci was made using a LI-Cor 6400 Portable Photosynthesis System. Soil application of EM1 combined with chemical control contributed to inhibiting Fusarium wilt of pea. Foliar application of EM1 combined with chemical control increased all gas exchange rates of pea leaves. Fusarium wilt of pea insignificantly decreased all gas exchange rates of pea leaves and the number of seeds per pod. The best method of EM1 application was soil treatment combined with chemical control, which increased all yield-related morphometric parameters of pea.

  8. Comparison and analysis of biological agent category lists based on biosafety and biodefense.

    Directory of Open Access Journals (Sweden)

    Deqiao Tian

    Full Text Available Biological agents pose a serious threat to human health, economic development, social stability and even national security. The classification of biological agents is a basic requirement for both biosafety and biodefense. We compared and analyzed the Biological Agent Laboratory Biosafety Category list and the defining criteria according to the World Health Organization (WHO, the National Institutes of Health (NIH, the European Union (EU and China. We also compared and analyzed the Biological Agent Biodefense Category list and the defining criteria according to the Centers for Disease Control and Prevention (CDC of the United States, the EU and Russia. The results show some inconsistencies among or between the two types of category lists and criteria. We suggest that the classification of biological agents based on laboratory biosafety should reduce the number of inconsistencies and contradictions. Developing countries should also produce lists of biological agents to direct their development of biodefense capabilities.To develop a suitable biological agent list should also strengthen international collaboration and cooperation.

  9. Hypersensitivity to biological agents-updated diagnosis, management, and treatment.

    Science.gov (United States)

    Galvão, Violeta Régnier; Castells, Mariana C

    2015-01-01

    Biological agents are used in the treatment of neoplastic, autoimmune, and inflammatory diseases and their clinical applications are becoming broader. Following their increased utilization, hypersensitivity reactions linked to these drugs have become more frequent, sometimes preventing the use of first-line therapies. The clinical presentation of hypersensitivity reactions to biological agents ranges from mild cutaneous manifestations to life-threatening reactions. In this scenario, rapid desensitization is a groundbreaking procedure that enables selected patients to receive the full treatment dose in a safe way, in spite of their immediate hypersensitivity reaction to the drug, and protects them against anaphylaxis. The aim of this review is to update and discuss some of the main biological agents used in clinical practice (rituximab, trastuzumab, cetuximab, ofatumumab, tocilizumab, brentuximab, omalizumab, and tumor necrosis factor alpha inhibitor agents) and their associated hypersensitivity reactions, including clinical presentations, diagnosis, and treatment in the acute setting. In addition, novel management options with rapid desensitization are presented.

  10. An Exercise in Biological Control.

    Science.gov (United States)

    Lennox, John; Duke, Michael

    1997-01-01

    Discusses the history of the use of pesticides and biological control. Introduces the concept of biological control as illustrated in the use of the entomopathogenic bacterium Bacillus thuringiensis and highlights laboratory demonstrations of Koch's postulates. Includes an exercise that offers the student and teacher several integrated learning…

  11. Morphology of the female reproductive system and physiological age-grading of Megamelus scutellaris (Hemiptera: Delphacidae), a biological control agent of water hyacinth

    Science.gov (United States)

    The morphology of the female reproductive system in Megamelus scutellaris Berg (Hemiptera:Delphacidae), a biocontrol agent of Eichhornia crassipes (Mart.) Solms, was examined using standard light microscopy techniques. Ovaries extracted from individuals dissected in phosphate buffered saline were ex...

  12. Massive Multi-Agent Systems Control

    Science.gov (United States)

    Campagne, Jean-Charles; Gardon, Alain; Collomb, Etienne; Nishida, Toyoaki

    2004-01-01

    In order to build massive multi-agent systems, considered as complex and dynamic systems, one needs a method to analyze and control the system. We suggest an approach using morphology to represent and control the state of large organizations composed of a great number of light software agents. Morphology is understood as representing the state of the multi-agent system as shapes in an abstract geometrical space, this notion is close to the notion of phase space in physics.

  13. Carbon Nanotubes: Detection of Chemical and Biological Warfare Agents

    Directory of Open Access Journals (Sweden)

    Om Kumar

    2008-09-01

    Full Text Available Discovery of carbon nanotubes has great impact on the development of newer methodologies and devicesuseful for the analysis of various types of chemicals. The functionalisation of CNTs with biomolecules relatedto chemical and biological warfare agents makes these useful for the detection of these agents. The detectionsensitivity can be increased manyfold. Various types of chemical and biological sensors were developed usingvarious type of carbon nanotubes as well as nano particles of different metals.Defence Science Journal, 2008, 58(5, pp.617-625, DOI:http://dx.doi.org/10.14429/dsj.58.1684

  14. Agent-Based Cooperative Control

    Science.gov (United States)

    2005-12-01

    IEEE Transactions on Automatic Control , vol. 45, issue 12, Dec, 2000, pp. 2253-2270. [15] A. M. Bloch, Dong Eui Chang, N. E. Leonard, J. E...Marsden, “Controlled Lagrangians and the stabilization of mechanical systems. II. Potential shaping,” IEEE Transactions on Automatic Control , vol. 46...a new approach to constructive nonlinear control,” IEEE Transactions on Automatic Control , Volume 49, Issue 7, July

  15. The Biological Control of the Malaria Vector

    Directory of Open Access Journals (Sweden)

    Layla Kamareddine

    2012-09-01

    Full Text Available The call for malaria control, over the last century, marked a new epoch in the history of this disease. Many control strategies targeting either the Plasmodium parasite or the Anopheles vector were shown to be effective. Yet, the emergence of drug resistant parasites and insecticide resistant mosquito strains, along with numerous health, environmental, and ecological side effects of many chemical agents, highlighted the need to develop alternative tools that either complement or substitute conventional malaria control approaches. The use of biological means is considered a fundamental part of the recently launched malaria eradication program and has so far shown promising results, although this approach is still in its infancy. This review presents an overview of the most promising biological control tools for malaria eradication, namely fungi, bacteria, larvivorous fish, parasites, viruses and nematodes.

  16. Potential of Biological Agents in Decontamination of Agricultural Soil

    Science.gov (United States)

    Javaid, Muhammad Kashif; Ashiq, Mehrban; Tahir, Muhammad

    2016-01-01

    Pesticides are widely used for the control of weeds, diseases, and pests of cultivated plants all over the world, mainly since the period after the Second World War. The use of pesticides is very extensive to control harm of pests all over the globe. Persistent nature of most of the synthetic pesticides causes serious environmental concerns. Decontamination of these hazardous chemicals is very essential. This review paper elaborates the potential of various biological agents in decontamination of agricultural soils. The agricultural crop fields are contaminated by the periodic applications of pesticides. Biodegradation is an ecofriendly, cost-effective, highly efficient approach compared to the physical and chemical methods which are expensive as well as unfriendly towards environment. Biodegradation is sensitive to the concentration levels of hydrogen peroxide and nitrogen along with microbial community, temperature, and pH changes. Experimental work for optimum conditions at lab scale can provide very fruitful results about specific bacterial, fungal strains. This study revealed an upper hand of bioremediation over physicochemical approaches. Further studies should be carried out to understand mechanisms of biotransformation. PMID:27293964

  17. Potential of Biological Agents in Decontamination of Agricultural Soil

    Directory of Open Access Journals (Sweden)

    Muhammad Kashif Javaid

    2016-01-01

    Full Text Available Pesticides are widely used for the control of weeds, diseases, and pests of cultivated plants all over the world, mainly since the period after the Second World War. The use of pesticides is very extensive to control harm of pests all over the globe. Persistent nature of most of the synthetic pesticides causes serious environmental concerns. Decontamination of these hazardous chemicals is very essential. This review paper elaborates the potential of various biological agents in decontamination of agricultural soils. The agricultural crop fields are contaminated by the periodic applications of pesticides. Biodegradation is an ecofriendly, cost-effective, highly efficient approach compared to the physical and chemical methods which are expensive as well as unfriendly towards environment. Biodegradation is sensitive to the concentration levels of hydrogen peroxide and nitrogen along with microbial community, temperature, and pH changes. Experimental work for optimum conditions at lab scale can provide very fruitful results about specific bacterial, fungal strains. This study revealed an upper hand of bioremediation over physicochemical approaches. Further studies should be carried out to understand mechanisms of biotransformation.

  18. The host range and impact of Bikasha collaris (Coleoptera: Chrysomelidae), a promising candidate agent for biological control of Chinese tallow, Triadica sebifera (Euphorbiaceae) in the United States

    Science.gov (United States)

    Native to China, the Chinese tallow, Triadica sebifera (Euphorbiaceae) is an aggressive woody invader in the southeastern United States. The flea beetle, Bikasha collaris (Coleoptera: Chrysomelidae), is a common herbivore attacking this plant in China. To evaluate its potential as a biological contr...

  19. Biological Warfare Agents, Toxins, Vectors and Pests as Biological Terrorism Agents

    Science.gov (United States)

    2003-07-01

    synthesis of >100 amino acid polypeptides, advanced genetic manipulation). Toxins as terrorism agents: 1. Botulinum toxin 2. Ricin 3...marginatum 5. Hyalomma Anatolicum Anatolicum 6. Dermacentor spp. 7. Rhipicephalus spp. 8. Amblyomma spp. 9. Mansonia spp. 10. Culex spp. 11

  20. Methodology and biological monitoring of exposure to chemical warfare agents

    Energy Technology Data Exchange (ETDEWEB)

    Shih, M.L.; Smith, J.R.; McMonagle, J.D. [Army Medical Research Inst. of Chemical Defense, Aberdeen Proving Ground, MD (United States)

    1995-06-01

    In the past few years, our institute has developed several GC/MS methods for the detection of the breakdown products of toxic organophosphonates (soman, sarin, GF) and vesicant sulfur mustard in biological samples. Recently we developed a modified GC/MS method for VX and are continually working on the methodology for lewisite and tabun. The purpose is to have an analytical tool to verify the exposure of chemical warfare agents in humans. Analytical procedures for quantitating the hydrolyzed phosphonic acids from nerve agents in environmental samples have been reported by many analysts. For more complex matrices such as biological samples, there is not yet a method reported. To make these polar acids amenable to gas chromatographic analysis a prior derivatization is needed. We found the pentafluorobenzyl ester derivatives of the phosphonates are suitable for verification and pharmacokinetic studies in biological samples. This method may also serve as an alternative method for confirmation purposes in environmental samples.

  1. Respiratory Protection Against Chemical and Biological Warfare Agents

    Directory of Open Access Journals (Sweden)

    G.K. Prasad

    2008-09-01

    Full Text Available Chemical and biological warfare (CBW agents pose unavoidable threat, both to soldiers and civilians.Exposure to such deadly agents amidst the CBW agents contaminated environment can be avoided bytaking proper protective measures. Respiratory protection is indispensable when the soldiers or civiliansare surrounded by such deadly environment as contamination-free air is needed for respiration purposes.In this context, an attempt has been made to review the literature for the past five decades on developmentof various protective devices for respiratory protection against aerosols, gases, and vapours of CBWagents. This review covers structural, textural, and adsorption properties of materials used in gas filtersand mechanical filters for the removal of CBW agents.Defence Science Journal, 2008, 58(5, pp.686-697, DOI:http://dx.doi.org/10.14429/dsj.58.1692

  2. Biological pest control in Mexico.

    Science.gov (United States)

    Williams, Trevor; Arredondo-Bernal, Hugo C; Rodríguez-del-Bosque, Luis A

    2013-01-01

    Mexico is a megadiverse country that forms part of the Mesoamerican biological corridor that connects North and South America. Mexico's biogeographical situation places it at risk from invasive exotic insect pests that enter from the United States, Central America, or the Caribbean. In this review we analyze the factors that contributed to some highly successful past programs involving classical biological control and/or the sterile insect technique (SIT). The present situation is then examined with reference to biological control, including SIT programs, targeted at seven major pests, with varying degrees of success. Finally, we analyze the current threats facing Mexico's agriculture industry from invasive pests that have recently entered the country or are about to do so. We conclude that despite a number of shortcomings, Mexico is better set to develop biological control-based pest control programs, particularly on an area-wide basis, than many other Latin American countries are. Classical and augmentative biological control and SIT-based programs are likely to provide effective and sustainable options for control of native and exotic pests, particularly when integrated into technology packages that meet farmers' needs across the great diversity of production systems in Mexico.

  3. Herbivory, Predation, and Biological Control.

    Science.gov (United States)

    Murphy, Terence M.; And Others

    1992-01-01

    Authors describe a set of controlled ecosystems that can be used to demonstrate the effects of herbivory on the health and growth of a plant population and of predation on the growth of a primary consumer population. The system also shows the effectiveness of biological pest control measures in a dramatic way. The construction of the ecosystems is…

  4. LIDAR for Detection of Chemical and Biological Warfare Agents

    Directory of Open Access Journals (Sweden)

    S Veerabuthiran

    2011-04-01

    Full Text Available Remote detection of chemical and biological warfare agents and toxic gases in the atmosphere is of current interest to both the military and civilian agencies. Out of all currently available techniques, no single technique provides efficient detection against such threats at significant standoff distances. Light detection and ranging (LIDAR technologies, based on the transmission of laser pulses and analysis of the return signals, have demonstrated impressive capabilities in remote detection of such toxic chemicals. LIDAR is a highly sensitive tool to detect the extremely low concentrations of various toxic agents present in the form of thin clouds at distances of few kilometer. The detection of these toxic clouds is based on the approach of first detecting and measuring the range of the clouds using the scattering phenomena and subsequently identifying the composition of toxic clouds using absorption and fluorescence phenomena. Laser Science and Technology Centre (LASTEC, Delhi has been working on the design and development of LIDAR systems for detection of chemical and biological warfare (CBW agents. In this paper, theoretical analysis of differential absorption LIDAR (DIAL for detection of chemical agents and fluorescence LIDAR for detection of biological agents has been discussed. For some typical parametric conditions, the received power levels from different ranges to detect specific concentrations of chemical or biological clouds have been computed and discussed. The technical details of the indigenously developed backscattering LIDAR, which detects and measures the distance of cloud layers up to 5 km is also presented.Defence Science Journal, 2011, 61(3, pp.241-250, DOI:http://dx.doi.org/10.14429/dsj.61.556

  5. Bioforensics: Characterization of biological weapons agents by NanoSIMS

    Energy Technology Data Exchange (ETDEWEB)

    Weber, P K; Ghosal, S; Leighton, T J; Wheeler, K E; Hutcheon, I D

    2007-02-26

    The anthrax attacks of Fall 2001 highlight the need to develop forensic methods based on multiple identifiers to determine the origin of biological weapons agents. Genetic typing methods (i.e., DNA and RNA-based) provide one attribution technology, but genetic information alone is not usually sufficient to determine the provenance of the material. Non-genetic identifiers, including elemental and isotopic signatures, provide complementary information that can be used to identify the means, geographic location and date of production. Under LDRD funding, we have successfully developed the techniques necessary to perform bioforensic characterization with the NanoSIMS at the individual spore level. We have developed methods for elemental and isotopic characterization at the single spore scale. We have developed methods for analyzing spore sections to map elemental abundance within spores. We have developed rapid focused ion beam (FIB) sectioning techniques for spores to preserve elemental and structural integrity. And we have developed a high-resolution depth profiling method to characterize the elemental distribution in individual spores without sectioning. We used these newly developed methods to study the controls on elemental abundances in spores, characterize the elemental distribution of in spores, and to study elemental uptake by spores. Our work under this LDRD project attracted FBI and DHS funding for applied purposes.

  6. FIPA agent based network distributed control system

    Energy Technology Data Exchange (ETDEWEB)

    D. Abbott; V. Gyurjyan; G. Heyes; E. Jastrzembski; C. Timmer; E. Wolin

    2003-03-01

    A control system with the capabilities to combine heterogeneous control systems or processes into a uniform homogeneous environment is discussed. This dynamically extensible system is an example of the software system at the agent level of abstraction. This level of abstraction considers agents as atomic entities that communicate to implement the functionality of the control system. Agents' engineering aspects are addressed by adopting the domain independent software standard, formulated by FIPA. Jade core Java classes are used as a FIPA specification implementation. A special, lightweight, XML RDFS based, control oriented, ontology markup language is developed to standardize the description of the arbitrary control system data processor. Control processes, described in this language, are integrated into the global system at runtime, without actual programming. Fault tolerance and recovery issues are also addressed.

  7. Biological Control of Fusarium oxysporum f. sp. melonis, the Causal Agent of Root Rot Disease of Greenhouse Cucurbits in Kerman Province of Iran

    Directory of Open Access Journals (Sweden)

    Sara Shafii Bafti

    2005-01-01

    Full Text Available Antagonistic activity of 178 soil actinomycete isolates was assayed against Fusarium oxysporum f. sp. melonis Schlecht, Emend (Snyde and Hansen cause of root rot and fusarium wilt of greenhouse cucurbits in Kerman Province, southeast of Iran. From tested isolates, Streptomyces olivaceus (strain 115 showed anti-fusarium activity revealed through screening and bioassays by agar disk and well-diffusion methods. The active strain was grown in submerged cultures for determination of growth curve and preparation of crude extract for further biological characterizations. Antifungal activity was fungistatic type on the pathogen mycelia. It is prominent that amending greenhouse soil mix with the S. olivaceus (strain 115 will reduce crop losses by the pathogen.

  8. Biologic Agents for Periodontal Regeneration and Implant Site Development

    Science.gov (United States)

    Suárez-López del Amo, Fernando; Monje, Alberto; Padial-Molina, Miguel; Tang, ZhiHui; Wang, Hom-Lay

    2015-01-01

    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). PMID:26509173

  9. 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.

  10. Temperature-dependent development and potential distribution of Episimus utilis (Lepidoptera: Tortricidae), a candidate biological control agent of Brazilian peppertree (Sapindales: Anacardiaceae) in Florida.

    Science.gov (United States)

    Manrique, Veronica; Cuda, James P; Overholt, William A; Diaz, Rodrigo

    2008-08-01

    The invasive Brazilian peppertree (Schinus terebinthifolius Raddi), native to South America, is widely established throughout central and south Florida. The defoliating leaflet-roller Episimus utilis Zimmerman was selected as potential biocontrol agent of this invasive species. The objectives of this study were to determine development rate and survival of E. utilis at seven constant temperatures (10, 15, 20, 25, 30, 33, and 35 degrees C) and generate prediction maps of the number of generations per year this species may exhibit in the United States. The rate of development of E. utilis as a function of temperature was modeled using linear regression to estimate a lower developmental threshold of 9.6 degrees C and the degree-day requirement of 588. The Logan nonlinear regression model was used to estimate an upper developmental threshold of 33 degrees C. Cold tolerance of E. utilis was examined using all insect stages, and each stage was exposed to three constant temperatures (10, 5, 0 degrees C) for 0.5, 1, 2, 4, and 8 d (or until all insects died). The pupal stage was the most cold tolerant with 100% mortality after 12 d at 0 degrees C. The pupal lethal times at 5 (Ltime50 = 10 d, Ltime90 = 28 d) and 0 degrees C (Ltime50 = 5 d, Ltime90 = 9 d) were used to generate isothermal lines to predict favorable regions for E. utilis establishment. A GIS map was generated to predict the number of generations of E. utilis (range, 0.5-9.8) across all Brazilian peppertree range in the United States. The potential for establishment of E. utilis and its probable distribution in the continental United States was examined.

  11. On the risk of extinction of a wild plant species through spillover of a biological control agent: Analysis of an ecosystem compartment model.

    NARCIS (Netherlands)

    Chalak, M.; Hemerik, L.; Werf, van der W.; Ruijs, A.; Ierland, van E.C.

    2010-01-01

    Invasive plant species can be controlled by introducing natural enemies (insect herbivores) from their native range. However, such introduction entails the risk that the introduced herbivores attack indigenous plant species in the area of introduction. Here, we study the effect of spillover of a her

  12. Potential of a strain of the entomopathogenic fungus Beauveria bassiana (Hypocreales: Cordycipitaceae) as a biological control agent against western flower thrips, Frankliniella occidentalis (Thysanoptera: Thripidae)

    Science.gov (United States)

    Five Beauveria bassiana strains were evaluated for control of western flower thrips. Strain RSB was the most virulent, causing 69-96% mortality at concentrations of 1×104 – 1×107 conidia mL-1, 10 days after inoculation of first instars. In greenhouse trials, RSB applied to broccoli foliage signifi...

  13. Vanadium compounds biological actions and potential as pharmacological agents.

    Science.gov (United States)

    Tsiani, E; Fantus, I G

    1997-03-01

    Vanadium is an element found in low concentrations in mammals, for which a function remains to be discovered. Over the past century, vanadium compounds have been suggested anecdotally as therapeutic agents for a variety of diseases. The discovery that vanadate inhibits various enzymes, in particular protein tyrosine phosphatases, and mimics many of the biological actions of insulin suggested a potential role in the therapy of diabetes mellitus. Successful use and an enhancement of insulin sensitivity in rodents and human diabetic subjects, as well as the finding that these agents are capable of stimulating metabolic effects while bypassing the insulin receptor and the early steps in insulin action, target these agents preferentially toward type II diabetes mellitus. Long-term safety remains a major concern, as tissue accumulation and relative nonspecificity of enzyme inhibition may result in adverse effects. Continued research into mechanism of action, consequences of chronic administration, and improvement of specificity is warranted. Regardless of their ultimate success or failure as therapeutic agents, vanadium compounds continue to be useful probes of enzyme structure and function in various biological processes. (Trends Endocrinol Metab 1997;8:51-58). (c) 1997, Elsevier Science Inc.

  14. 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

  15. Control theory meets synthetic biology.

    Science.gov (United States)

    Del Vecchio, Domitilla; Dy, Aaron J; Qian, Yili

    2016-07-01

    The past several years have witnessed an increased presence of control theoretic concepts in synthetic biology. This review presents an organized summary of how these control design concepts have been applied to tackle a variety of problems faced when building synthetic biomolecular circuits in living cells. In particular, we describe success stories that demonstrate how simple or more elaborate control design methods can be used to make the behaviour of synthetic genetic circuits within a single cell or across a cell population more reliable, predictable and robust to perturbations. The description especially highlights technical challenges that uniquely arise from the need to implement control designs within a new hardware setting, along with implemented or proposed solutions. Some engineering solutions employing complex feedback control schemes are also described, which, however, still require a deeper theoretical analysis of stability, performance and robustness properties. Overall, this paper should help synthetic biologists become familiar with feedback control concepts as they can be used in their application area. At the same time, it should provide some domain knowledge to control theorists who wish to enter the rising and exciting field of synthetic biology.

  16. Relação entre a lagarta-do-cartucho e seus agentes de controle biológico natural na produção de milho Relationship between fall armyworm and their natural biological control agents in the maize crop

    Directory of Open Access Journals (Sweden)

    Maria de Lourdes Corrêa Figueiredo

    2006-12-01

    Full Text Available Este trabalho teve como objetivo quantificar as perdas na cultura do milho BRS 3123 decorrentes do ataque da lagarta-do-cartucho (Spodoptera frugiperda, na ausência e presença de seus inimigos naturais. Aos 15 dias depois da emergência da planta, foi realizada uma infestação artificial da praga (uma postura por metro quadrado. As lagartas alimentaram-se da planta, sem a interferência de seus inimigos naturais, pela utilização de uma gaiola de proteção (inicial, de dois dias depois da infestação, até uma proteção máxima de 16 dias. O dano da praga, determinado por uma escala de notas de 0 (plantas sem dano a 5 (plantas mortas, foi em média de 4,01, 1,39, 1,09 e 0,93 para o período de proteção da praga de 16, 6, 4 e 2 dias, respectivamente. Na ausência de agentes de controle biológico, o ataque da praga ocasionou perdas na produção de matéria seca de 47,27% e perdas no rendimento de grãos de 54,49%. Os resultados evidenciaram a importância dos inimigos naturais na supressão de lagartas de S. frugiperda na cultura de milho.This work had the objective of quantifying the losses in the maize hybrid BRS 3123 due to the attack of fall armyworm (Spodoptera frugiperda, in the absence or presence of its natural enemies. Fifteen days after the plant emergency, an artificial infestation (one egg mass per square meter was accomplished. The larvae fed on the plant, without the interference of its natural enemies, by using an appropriated protection cage (initial protection for two days after infestation, until a maximum protection period of 16 days. The damage caused by the pest, determined through a visual scale from 0 (plants without damage to 5 (dead plants, was on average, 4.01, 1.39, 1.09 and 0.93 for the pest protection period of 16, 6, 4 and 2 days, respectively. In the absence of the biological control agents, the attack of the pest caused losses of 47.27% in the dry matter production and losses of 54.49% in grain yield. The

  17. Intestinal nematodes: biology and control.

    Science.gov (United States)

    Epe, Christian

    2009-11-01

    A variety of nematodes occur in dogs and cats. Several nematode species inhabit the small and large intestines. Important species that live in the small intestine are roundworms of the genus Toxocara (T canis, T cati) and Toxascaris (ie, T leonina), and hookworms of the genus Ancylostoma (A caninum, A braziliense, A tubaeforme) or Uncinaria (U stenocephala). Parasites of the large intestine are nematodes of the genus Trichuris (ie, whipworms, T vulpis). After a comprehensive description of their life cycle and biology, which are indispensable for understanding and justifying their control, current recommendations for nematode control are presented and discussed thereafter.

  18. Application of Controlled Freezing Point Technique Combined with Biological Antistaling Agent in Preservation of Aquatic Products%冰温结合生物保鲜剂技术在水产品保鲜中的应用

    Institute of Scientific and Technical Information of China (English)

    杨胜平; 谢晶

    2009-01-01

    The effect of controlled freezing point technique on the quality of aquatic products and the antibacterial function of several common biological antistaling agents were analyzed. The application of food fresh keeping by means of combining these two technologies was also proposed. The review will provide important theoretical basis for the research and enhancement of the application of these two technologies in food industry.%阐述了冰温保鲜技术对水产品品质的影响,以及几种常见生物保鲜剂的抑菌作用.并介绍了冰温贮藏结合生物保鲜剂技术在食品保鲜中的应用,为进一步研究冰温及生物保鲜剂技术和扩大它们在食品工业中的应用提供重要的理论基础.

  19. Genetically engineered biological agents in therapy for systemic lupus erythematosus

    Directory of Open Access Journals (Sweden)

    Elena Aleksandrovna Aseeva

    2013-01-01

    Full Text Available Systemic lupus erythematosus (SLE is a prototype for chronic autoimmune disease. Its prevalence is 20 to 70 cases per 100,000 women and varies by race and ethnicity. Despite considerable progress in traditional therapy, many problems associated with the management of these patients need to be immediately solved: thus, 50-80% are found to have activity signs and/or frequent exacerbations and about 30% of the patients have to stop work; Class IV lupus nephritis increases the risk of terminalrenal failure. In the past 20 years great progress has been made in studying the pathogenesis of SLE: biological targets to affect drugs have been sought and fundamentally new therapeutic goals defined. Belimumab is the first genetically biological agent specially designed to treat SLE, which is rightly regarded as one of the most important achievements of rheumatology in the past 50 years.

  20. Update on the use of systemic biologic agents in the treatment of noninfectious uveitis

    Directory of Open Access Journals (Sweden)

    Pasadhika S

    2014-02-01

    Full Text Available Sirichai Pasadhika,1 James T Rosenbaum2 1Department of Ophthalmology, Southern Arizona Veterans Administration Health Care System, Tucson, AZ, USA; 2Legacy Devers Eye Institute, Portland, OR, USA Abstract: Uveitis is one of the leading causes of blindness worldwide. Noninfectious uveitis may be associated with other systemic conditions, such as human leukocyte antigen B27-related spondyloarthropathies, inflammatory bowel disease, juvenile idiopathic arthritis, Behçet's disease, and sarcoidosis. Conventional therapy with corticosteroids and immunosuppressive agents (such as methotrexate, azathioprine, mycophenolate mofetil, and cyclosporine may not be sufficient to control ocular inflammation or prevent non-ophthalmic complications in refractory patients. Off-label use of biologic response modifiers has been studied as primary and secondary therapeutic agents. They are very useful when conventional immunosuppressive therapy has failed or has been poorly tolerated, or to treat concomitant ophthalmic and systemic inflammation that might benefit from these medications. Biologic therapy, primarily infliximab, and adalimumab, have been shown to be rapidly effective for the treatment of various subtypes of refractory uveitis and retinal vasculitis, especially Behçet's disease-related eye conditions and the uveitis associated with juvenile idiopathic arthritis. Other agents such as golimumab, abatacept, canakinumab, gevokizumab, tocilizumab, and alemtuzumab may have great future promise for the treatment of uveitis. It has been shown that with proper monitoring, biologic therapy can significantly improve quality of life in patients with uveitis, particularly those with concurrent systemic symptoms. However, given high cost as well as the limited long-term safety data, we do not routinely recommend biologics as first-line therapy for noninfectious uveitis in most patients. These agents should be used with caution by experienced clinicians. The present

  1. Micro-radiography of biological samples with medical contrast agents

    Energy Technology Data Exchange (ETDEWEB)

    Dammer, J., E-mail: jiri.dammer@lf1.cuni.cz [Charles University in Prague, First Faculty of Medicine, Salmovská 1, 120 00 Prague 2 (Czech Republic); Hospital Na Bulovce, Department of Radiological Physics, Budinova 2, 180 81 Prague 8 (Czech Republic); Institute of Experimental and Applied Physics, Czech Technical University in Prague, Horska 3a/22, 128 00 Prague 2 (Czech Republic); Weyda, F. [Faculty of Science, University of South Bohemia, Branisovska 31, 370 05 Ceske Budejovice (Czech Republic); Benes, J. [Charles University in Prague, First Faculty of Medicine, Salmovská 1, 120 00 Prague 2 (Czech Republic); Sopko, V. [Hospital Na Bulovce, Department of Radiological Physics, Budinova 2, 180 81 Prague 8 (Czech Republic); Institute of Experimental and Applied Physics, Czech Technical University in Prague, Horska 3a/22, 128 00 Prague 2 (Czech Republic); Gelbic, I. [Biology Centre, AS CR, Institute of Entomology, Department of Biochemistry and Physiology, Branisovska 31, CZ-37005 Ceske Budejovice (Czech Republic)

    2013-12-01

    Micro-radiography is an imaging technique that uses X-rays to study the internal structures of objects. This fast and easy imaging tool is based on differential X-ray attenuation by various tissues and structures within biological samples. The experimental setup described is based on the semiconductor pixel X-ray detector Medipix2 and X-ray micro-focus tube. Our micro-radiographic system has been recently used not only for the examination of internal structures of various arthropods and other biological objects but also for tracing some processes in selected model species (we used living larvae of mosquito Culex quinquefasciatus). Low concentrations of iodine, lanthanum or gold particles were used as a tracer (contrast agent). Such contrast agents increase the absorption of X-rays and allow a better visibility of internal structures of model organisms (especially the various cavities, pores, etc.). In addition, the movement of tracers in selected timing experiments demonstrates some physiological functions of digestive and excretory system.

  2. Biological soil crusts: a fundamental organizing agent in global drylands

    Science.gov (United States)

    Belnap, J.; Zhang, Y.

    2013-12-01

    Ecosystem function is profoundly affected by plant community composition, which is ultimately determined by factors that govern seed retention. Dryland ecosystems constitute ~35% of terrestrial surfaces, with most soils in these regions covered by biological soil crusts (biocrusts), a community whose autotrophs are dominated by cyanobacteria, lichens, and mosses. Studies at 550 sites revealed that plant community composition was controlled by the interaction among biocrust type, disturbance regime, and external morphology of seeds. In bare soils (due to disturbance), all seed types were present in the seedbank and plant community. As biocrusts became better developed (i.e., the cover of lichens and mosses increased), they more strongly filtered out seeds with appendages. Thus, soils under late successional biocrusts contained seedbanks dominated by smooth seeds and vascular plants growing in late successional biocrusts were dominated by those with smooth seeds. Therefore, the tension between the removal of biocrusts by soil surface disturbance and their recovery creates a shifting mosaic of plant patch types in both space and time. Because changes in vascular plant communities reverberate throughout both below ground and above ground food webs and thus affect multiple trophic levels, we propose that biocrusts are a fundamental organizing agent in drylands worldwide. Future increased demand for resources will intensify land use both temporally and spatially, resulting in an increased rate of biocrust loss across larger areas. As a result, we can expect shifts in the composition and distribution of plant communities, accompanied by concomitant changes in many aspects of dryland ecosystems. Conceptual model of shifting dryland plant mosaics through space and time. Within the large circles, soil surface type changes with time in the same space, going from bare uncrusted soil (B) to cyanobacterial biocrust (C) to lichen/moss (L/M) biocrust. Disturbance (D) drives the

  3. The use of contrast agent for imaging biological samples

    Energy Technology Data Exchange (ETDEWEB)

    Dammer, J; Sopko, V; Jakubek, J [Institute of Experimental and Applied Physics, Czech Technical University in Prague, Horska 3a/22, CZ 12800 Prague 2 (Czech Republic); Weyda, F, E-mail: jiri.dammer@utef.cvut.cz [Biological center of the Academy of Sciences of the Czech Republic, Institute of Entomology, Branisovska 31, CZ-37005 Ceske Budejovice (Czech Republic)

    2011-01-15

    The technique of X-ray transmission imaging has been available for over a century and is still among the fastest and easiest approaches to the studies of internal structure of biological samples. Recent advances in semiconductor technology have led to the development of new types of X-ray detectors with direct conversion of interacting X-ray photon to an electric signal. Semiconductor pixel detectors seem to be specially promising; compared to the film technique, they provide single-quantum and real-time digital information about the objects being studied. We describe the recently developed radiographic apparatus, equipped with Medipix2 semiconductor pixel detector. The detector is used as an imager that counts individual photons of ionizing radiation, emitted by an X-ray tube (micro- or nano-focus FeinFocus). Thanks to the wide dynamic range of the Medipix2 detector and its high spatial resolution better than 1{mu}m, the setup is particularly suitable for radiographic imaging of small biological samples, including in-vivo observations with contrast agent (Optiray). Along with the description of the apparatus we provide examples of the use iodine contrast agent as a tracer in various insects as model organisms. The motivation of our work is to develop our imaging techniques as non-destructive and non-invasive. Microradiographic imaging helps detect organisms living in a not visible environment, visualize the internal biological processes and also to resolve the details of their body (morphology). Tiny live insects are an ideal object for our studies.

  4. Health protection: Toxic agent and radiation control.

    Science.gov (United States)

    1983-01-01

    It is estimated that of the four million chemical compounds which have been synthesized or isolated from natural materials, more than 55,000 are produced commercially. Approximately 1,000 new compounds are introduced annually; pesticide formulations alone contain about 1,500 active chemical ingredients. Diagnostic x-rays are used extensively in medicine and dentistry. Over 2,000 chemicals are suspected carcinogens in laboratory animals--epidemiologic evidence suggests that 26 of these chemicals and/or industrial processes are carcinogenic in humans. More than 20 agents are known to be associated with birth defects in humans; 47 atmospheric contaminants have been identified in animal studies as recognized carcinogens and 128 as mutagens; and, of the 765 contaminants identified in drinking water, 12 were recognized carcinogens, 31 suspected carcinogens, and 59 mutagens. Radiation has known carcinogenic and genetic effects at significant levels of exposure. Problems with toxic agents and radiation sources occur not only in industry, but also in medical and dental care (x-rays and drugs), agriculture (pesticides and herbicides), Government activities (biological and chemical agents), consumer products (incorrect use of consumer products which contain toxic substances), and natural sources (fungal products).

  5. Combination therapy with leflunomide and genetic engineering biological agents

    Directory of Open Access Journals (Sweden)

    Nataliya Vladimirovna Chichasova

    2011-06-01

    Full Text Available The paper gives data on the use of a combination of genetic engineering biological agents (GEBAs and leflunomide in patients with rheumatoid arthritis (RA. In accordance with the international guidelines, the majority of GEBAs should be given in a combination with methotrexate (MTX, which increases the efficacy of a number of GEBAs (tumor necrosis factor-α inhibitors, rituximab and affects tolerability (remikeid, humira. However, MTX cannot be always used in real practice. The data given in the paper on the efficiency and safety of the coadministration of leflunomide and a GEBA in patients with active RA, which are based on the results of randomized studies and national registers, including the Russian one, point to the compatibility of the results of treatment with this and GEBA-MTX combinations.

  6. Engineered plant biomass particles coated with biological agents

    Science.gov (United States)

    Dooley, James H.; Lanning, David N.

    2014-06-24

    Plant biomass particles coated with a biological agent such as a bacterium or seed, characterized by a length dimension (L) aligned substantially parallel to a grain direction and defining a substantially uniform distance along the grain, a width dimension (W) normal to L and aligned cross grain, and a height dimension (H) normal to W and L. In particular, the L.times.H dimensions define a pair of substantially parallel side surfaces characterized by substantially intact longitudinally arrayed fibers, the W.times.H dimensions define a pair of substantially parallel end surfaces characterized by crosscut fibers and end checking between fibers, and the L.times.W dimensions define a pair of substantially parallel top and bottom surfaces.

  7. "Protected biological control"- Biological pest management in the greenhouse industry

    NARCIS (Netherlands)

    Pilkington, L.J.; Messelink, G.J.; Lenteren, van J.C.; Mottee, Le K.

    2010-01-01

    This paper briefly describes the foundations and characteristics of biological control in protected cropping and what drivers are behind adoption of this management system within this industry. Examining a brief history of biological control in greenhouses and what makes it a successful management s

  8. Biological Activities of Phosphocitrate: A Potential Meniscal Protective Agent

    Directory of Open Access Journals (Sweden)

    Yubo Sun

    2013-01-01

    Full Text Available Phosphocitrate (PC inhibited meniscal calcification and the development of calcium crystal-associated osteoarthritis (OA in Hartley guinea pigs. However, the mechanisms remain elusive. This study sought to examine the biological activities of PC in the absence of calcium crystals and test the hypothesis that PC is potentially a meniscal protective agent. We found that PC downregulated the expression of many genes classified in cell proliferation, ossification, prostaglandin metabolic process, and wound healing, including bloom syndrome RecQ helicase-like, cell division cycle 7 homolog, cell division cycle 25 homolog C, ankylosis progressive homolog, prostaglandin-endoperoxide synthases-1/cyclooxygenase-1, and plasminogen activator urokinase receptor. In contrast, PC stimulated the expression of many genes classified in fibroblast growth factor receptor signaling pathway, collagen fibril organization, and extracellular structure organization, including fibroblast growth factor 7, collagen type I, alpha 1, and collagen type XI, alpha 1. Consistent with its effect on the expression of genes classified in cell proliferation, collagen fibril organization, and ossification, PC inhibited the proliferation of OA meniscal cells and meniscal cell-mediated calcification while stimulating the production of collagens. These findings indicate that PC is potentially a meniscal-protective agent and a disease-modifying drug for arthritis associated with severe meniscal degeneration.

  9. Chemiluminescence assay for the detection of biological warfare agents

    Energy Technology Data Exchange (ETDEWEB)

    Langry, K; Horn, J

    1999-11-05

    A chemiluminescent homogeneous immunoassay and a hand-size multiassay reader are described that could be used for detecting biological materials. The special feature of the assay is that it employs two different antibodies that each bind to a unique epitope on the same antigen. Each group of epitope-specific antibodies has linked to it an enzyme of a proximal-enzyme pair. One enzyme of the pair utilizes a substrate in high concentration to produce a second substrate required by the second enzyme. This new substrate enables the second enzyme to function. The reaction of the second enzyme is configured to produce light. This chemiluminescence is detected with a charge-coupled device (CCD) camera. The proximal pair enzymes must be in close proximity to one another to allow the second enzyme to react with the product of the first enzyme. This only occurs when the enzyme-linked antibodies are attached to the antigen, whether antigen is a single protein with multiple epitopes or the surface of a cell with a variety of different antigens. As a result of their juxtaposition, the enzymes produce light only in the presence of the biological material. A brief description is given as to how this assay could be utilized in a personal bio-agent detector system.

  10. Successful biological control of tropical soda apple in Florida

    Science.gov (United States)

    Tropical soda apple, Solanum viarum, is a small shrub native to tropical regions of Brazil, Paraguay, and Argentina. This weed was first found in Florida in 1988. In May 2003, a leaf feeding beetle, Gratiana boliviana, from South America was released in Florida as a biological control agent of tro...

  11. Identification and evaluation of Trichogramma parasitoids for biological pest control

    NARCIS (Netherlands)

    Silva, I.M.M.S.

    1999-01-01

    Egg parasitoids of the genus Trichogramma are used as biological control agents against lepidopterous pests. From the 180 species described world-wide, only 5 have large scale application. The development of better methods to select other Trichogramma species/strains is necessary for a more effectiv

  12. Biological control and sustainable food production

    NARCIS (Netherlands)

    Bale, J.S.; Lenteren, van J.C.; Bigler, F.

    2008-01-01

    The use of biological control for the management of pest insects pre-dates the modern pesticide era. The first major successes in biological control occurred with exotic pests controlled by natural enemy species collected from the country or area of origin of the pest (classical control). Augmentati

  13. Persistence with biologic agents for the treatment of rheumatoid arthritis in Japan

    Science.gov (United States)

    Mahlich, Jörg; Sruamsiri, Rosarin

    2016-01-01

    Background To assess persistence rates of biologic agents for the treatment of rheumatoid arthritis in Japan. Methods Based on Japanese claims data of 16,214 patients between 2012 and 2014, 6-, 12-, and 18-month persistence rates of different biologic agents were calculated. Determinants of persistence were assessed by means of a multivariate Cox proportional hazard model controlling for age, sex, and comorbidities. A sensitivity analysis was performed with different definitions of persistence and parametric survival analysis. Results Overall persistence rates in Japan are high and reach 86% after 1 year in the entire sample. The persistence rate for the biologic-naïve subpopulation is above 95%. Persistence is higher for older patients (hazard ratio 0.60 [95% confidence interval 0.40–0.91] for >75 years compared to ≤60 years) and lower for patients with a high comorbidity score (hazard ratio 1.33; 95% confidence interval 1.03–1.70 for Charlson Comorbidity Index score 3–5 compared to ≤2). We found a high variation of persistence between different drugs. Conclusion Japanese rheumatoid arthritis patients have a high persistence rate of biologic treatments. However, multiple factors affect the persistence rate of Japanese patients, including age, comorbidities, and patient type. Naïve patients tend to have a higher persistence rate than continuing biologic patients. PMID:27540283

  14. Agents-based distributed processes control systems

    Directory of Open Access Journals (Sweden)

    Adrian Gligor

    2011-12-01

    Full Text Available Large industrial distributed systems have revealed a remarkable development in recent years. We may note an increase of their structural and functional complexity, at the same time with those on requirements side. These are some reasons why there are involvednumerous researches, energy and resources to solve problems related to these types of systems. The paper addresses the issue of industrial distributed systems with special attention being given to the distributed industrial processes control systems. A solution for a distributed process control system based on mobile intelligent agents is presented.The main objective of the proposed system is to provide an optimal solution in terms of costs, maintenance, reliability and flexibility. The paper focuses on requirements, architecture, functionality and advantages brought by the proposed solution.

  15. Chemical Biology Strategies for Biofilm Control.

    Science.gov (United States)

    Yang, Liang; Givskov, Michael

    2015-08-01

    Microbes live as densely populated multicellular surface-attached biofilm communities embedded in self-generated, extracellular polymeric substances (EPSs). EPSs serve as a scaffold for cross-linking biofilm cells and support development of biofilm architecture and functions. Biofilms can have a clear negative impact on humans, where biofilms are a common denominator in many chronic diseases in which they prime development of destructive inflammatory conditions and the failure of our immune system to efficiently cope with them. Our current assortment of antimicrobial agents cannot efficiently eradicate biofilms. For industrial applications, the removal of biofilms within production machinery in the paper and hygienic food packaging industry, cooling water circuits, and drinking water manufacturing systems can be critical for the safety and efficacy of those processes. Biofilm formation is a dynamic process that involves microbial cell migration, cell-to-cell signaling and interactions, EPS synthesis, and cell-EPS interactions. Recent progress of fundamental biofilm research has shed light on novel chemical biology strategies for biofilm control. In this article, chemical biology strategies targeting the bacterial intercellular and intracellular signaling pathways will be discussed.

  16. Cement industry control system based on multi agent

    Institute of Scientific and Technical Information of China (English)

    王海东; 邱冠周; 黄圣生

    2004-01-01

    Cement production is characterized by its great capacity, long-time delay, multi variables, difficult measurement and muhi disturbances. According to the distributed intelligent control strategy based on the multi agent, the multi agent control system of cement production is built, which includes integrated optimal control and diagnosis control. The distributed and multiple level structure of multi agent system for the cement control is studied. The optimal agent is in the distributed state, which aims at the partial process of the cement production, and forms the optimal layer. The diagnosis agent located on the diagnosis layer is the diagnosis unit which aims at the whole process of the cement production, and the central management unit of the system. The system cooperation is realized by the communication among optimal agents and diagnosis agent. The architecture of the optimal agent and the diagnosis agent are designed. The detailed functions of the optimal agent and the diagnosis agent are analyzed.At last the realization methods of the agents are given, and the application of the multi agent control system is presented. The multi agent system has been successfully applied to the off-line control of one cement plant with capacity of 5 000 t/d. The results show that the average yield of the clinker increases 9.3% and the coal consumption decreases 7.5 kg/t.

  17. Biology and Water Pollution Control.

    Science.gov (United States)

    Warren, Charles E.

    Within this text, the reader is attuned to the role biology can and should play in combating the alarming increase in water pollution. Both the urgency of the problem and the biological techniques that are being developed to cope with the water pollution crisis are scrutinized; what is and is not known about the problem is explained; past,…

  18. Control effect of five biological agents on vegetable root-knot nematodes in greenhouse%5种生物制剂对设施蔬菜根结线虫防治技术研究

    Institute of Scientific and Technical Information of China (English)

    席先梅; 白全江; 张庆萍; 李玉民; 贺小勇; 孔庆全; 魏海明; 赵存虎

    2015-01-01

    蔬菜根结线虫已成为内蒙古赤峰市设施蔬菜园区的主要病害,对黄瓜和番茄造成严重的产量损失,为了筛选高效、安全的生物杀菌剂,2011-2012年在赤峰市松山区设施蔬菜园区进行了5种不同生物杀菌剂对设施黄瓜和番茄根结线虫防治的田间试验,在黄瓜和番茄定植时用100亿 cfu/g 厚孢轮枝菌粉剂0.2 kg/667 m2撒施,2%阿维菌素+多聚糖乳油3000倍稀释液灌根处理,0.2亿 cfu/g 淡紫拟青霉颗粒剂5 kg/667 m2撒施,10亿 cfu/mL 蜡质芽胞杆菌水剂6 L/667 m2灌根,1.8%阿维菌素乳油500倍稀释液灌根,设4次重复,并设空白对照。定植20 d 后再用同样的浓度和方法处理一次,结果表明:5种生物杀菌剂对黄瓜和番茄根结线虫的防治效果为20%~60%,10亿cfu/mL 蜡质芽胞杆菌水剂效果最好,达到56.3%,同时可以提高黄瓜和番茄的商品性,适于在设施蔬菜上推广使用。%Root-knot nematode has become the major threat for greenhouse vegetable production in Chifeng City of Inner Mongolia,and caused serious yield losses on cucumber and tomato.The field experiment was conducted to determine the effect of five biological agents against cucumber and tomato root-knot nematodes in greenhouse during 2011-2012.10 billions/g Verticillium chlamydosporium DP (0.2 kg/667 m2 )and 0.02 billions/g Paecilo-myces lilacinus GR (5 kg/667 m2 )were manually applied,and 2% abamectin+polysaccharide EC (3 000×),1 billion cfu/mL Bacillus cereus AS (6 L/667 m2 )and 1.8% abamectin EC (500×)were applied by drenching at the stage that the cucumber seedlings were transplanted into greenhouse.All the bioagents were reapplied once 20 days after the transplantation.Each treatment had 4 replicates,and the cucumber and tomato seedlings treated with water were used as the control.The results showed that all these bioagents could increase the cucumber and tomato production and

  19. The influence of the workplace-related biological agents on the immune systems of emergency medical personnel.

    Science.gov (United States)

    Brewczyńska, Aleksandra; Depczyńska, Daria; Borecka, Anna; Winnicka, Izabela; Kubiak, Leszek; Skopińska-Różewska, Ewa; Niemcewicz, Marcin; Kocik, Janusz

    2015-01-01

    Emergency medical services workers' (EMSWs) acute exposures to many biological agents are frequent and well recognised in their workplaces, as well as occupational diseases resulting from some of these exposures. At the same time, there is only scant information on the adverse effects of chronic exposure to biological hazard factors on the immune systems of EMSWs. In the Polish legislation system, the Ordinance of the Minister of Health about harmful biological agents in the workplace and ways of protecting workers from exposure to those agents is an implement of Directive 2000/54/EC, which deals thoroughly with those issues in European Union Countries. Emergency medical services workers play an essential role as primary providers of pre-hospital emergency medical care, and they are part of the integral components of disaster response. Traumatic experiences can affect emergency medical staff immune systems negatively, by functioning as a chronic stressor. Conscious use of biological agents in workplaces such as microbial laboratories can be easily controlled and monitored. However, risk assessment is more difficult for workers when they are exposed unintentionally to biological agents. Exposure to bio-aerosols is considered especially harmful. This review summarises available information about biological risk factors for emergency medical services workers, and some information about the influence of these factors on their immune systems.

  20. Control Prosody using Multi-Agent System

    Directory of Open Access Journals (Sweden)

    Kenji MATSUI

    2014-03-01

    Full Text Available Persons who have undergone a laryngectomy have a few options to partially restore speech but no completely satisfactory device. Even though the use of an electrolarynx (EL is the easiest way for a patient to produce speech, it does not produce a natural tone and appearance is far from normal. Because of that and the fact that none of them are hands-free, the feasibility of using a motion sensor to replace a conventional EL user interface has been explored. A mobile device motion sensor with multi-agent platform has been used to investigate on/off and pitch frequency control capability. A very small battery operated ARM-based control unit has also been developed to evaluate the motion sensor based user-interface. This control unit is placed on the wrist and the vibration device against the throat using support bandage. Two different conversion methods were used for the forearm tilt angle to pitch frequency conversion: linear mapping method and F0 template-based method A perceptual evaluation has been performed with two well-trained normal speakers and ten subjects. The results of the evaluation study showed that both methods are able to produce better speech quality in terms of the naturalness.

  1. Biological control and nutrition: food for thought

    Science.gov (United States)

    Chemical pesticides are used frequently to combat arthropod pests that plague crops; however, these compounds come with potential risks to the environment and human health. Research efforts have focused on using natural agents as an alternative to these chemical insecticides. These biological contro...

  2. Agent-Based Decentralized Control Method for Islanded Microgrids

    DEFF Research Database (Denmark)

    Li, Qiang; Chen, Feixiong; Chen, Minyou;

    2016-01-01

    In this paper, an agent-based decentralized control model for islanded microgrids is proposed, which consists of a two-layer control structure. The bottom layer is the electrical distribution microgrid, while the top layer is the communication network composed of agents. An agent is regarded as a...

  3. Persistence with biologic agents for the treatment of rheumatoid arthritis in Japan

    Directory of Open Access Journals (Sweden)

    Mahlich J

    2016-08-01

    Full Text Available Jörg Mahlich,1,2 Rosarin Sruamsiri1,3 1Health Economics, Janssen Pharmaceutical KK, Tokyo, Japan; 2Düsseldorf Institute for Competition Economics (DICE, University of Düsseldorf, Düsseldorf, Germany; 3Center of Pharmaceutical Outcomes Research, Department of Pharmacy Practice, Faculty of Pharmaceutical Sciences, Naresuan University, Phitsanulok, Thailand Background: To assess persistence rates of biologic agents for the treatment of rheumatoid arthritis in Japan.Methods: Based on Japanese claims data of 16,214 patients between 2012 and 2014, 6-, 12-, and 18-month persistence rates of different biologic agents were calculated. Determinants of persistence were assessed by means of a multivariate Cox proportional hazard model controlling for age, sex, and comorbidities. A sensitivity analysis was performed with different definitions of persistence and parametric survival analysis.Results: Overall persistence rates in Japan are high and reach 86% after 1 year in the entire sample. The persistence rate for the biologic-naïve subpopulation is above 95%. Persistence is higher for older patients (hazard ratio 0.60 [95% confidence interval 0.40–0.91] for >75 years compared to ≤60 years and lower for patients with a high comorbidity score (hazard ratio 1.33; 95% confidence interval 1.03–1.70 for Charlson Comorbidity Index score 3–5 compared to ≤2. We found a high variation of persistence between different drugs.Conclusion: Japanese rheumatoid arthritis patients have a high persistence rate of biologic treatments. However, multiple factors affect the persistence rate of Japanese patients, including age, comorbidities, and patient type. Naïve patients tend to have a higher persistence rate than continuing biologic patients. Keywords: Japan, rheumatoid arthritis, database analysis, persistence, biologics

  4. [Activities of the National Information Center for Biological Agents present at workplace and preliminary analysis of data collected by the National Register of Biological Agents].

    Science.gov (United States)

    Kozajda, Anna; Szadkowska-Stańczyk, Irena

    2009-01-01

    The National Information Centre for Biological Agents Present at Workplaces and the National Register of Biological Agents were established in the Nofer Institute of Occupational Medicine in 2005. The former carries out consultation and education activities concerned with occupational exposure and risk assessment, planning and implementation of preventive programs and accurate registration of reliable information about the use of biological agents. The latter aims at collecting and analyzing the aforesaid information obtained from employers for research, diagnostic or industrial purposes. The data base is a source of information for occupational environment supervising inspections and occupational health service. useful among others in planning various forms of prevention. As of December 10, 2008 there were 281 notifications from companies using biological agents (for the following purposes: research--34, diagnostic--225 and industrial--22). The majority of notifications were obtained from different diagnostic laboratories and universities/ research institutes. In total, 2197 workers, including 2011 (91.5%) women and 186 (8.5%) men were exposed to biological agents, were registered.

  5. Biology-Inspired Autonomous Control

    Science.gov (United States)

    2011-08-31

    of, and perhaps will not be tolerated in, manmade critical systems. Although this paper does not directly address questions of ethics associated...political, ethical , and moral issues associated with the use of autonomous systems in warfare will be debated long after the technology hurdles to...accessible discussion on the interplay of biochemistry, genetics and embryology in animal evolution; Wagner, 2005 describes biological concepts of

  6. Biological Control of Mosquitoes with Mermithids

    OpenAIRE

    Platzer, E. G.

    1981-01-01

    Mermithid nematodes parasitizing mosquitoes have substantial potential for vector control. Studies on the physiological ecology of Romanomermis culicivorax have defined some of the general requirements of mermithid nematodes and produced general guidelines for the experimental release of mermithids in biological control. Experimental field studies have established the biological control potential of R. culicivorax, but further development and ulilization of this parasite will require a substa...

  7. Use of biologic agents in combination with other therapies for the treatment of psoriasis.

    Science.gov (United States)

    Cather, Jennifer C; Crowley, Jeffrey J

    2014-12-01

    Psoriasis is a chronic inflammatory skin disorder, which is associated with a significant negative impact on a patient's quality of life. Traditional therapies for psoriasis are often not able to meet desired treatment goals, and high-dose and/or long-term use is associated with toxicities that can result in end-organ damage. An improved understanding of the involvement of cytokines in the etiology of psoriasis has led to the development of biologic agents targeting tumor necrosis factor (TNF)-α and interleukins (ILs)-12/23. While biologic agents have improved treatment outcomes, they are not effective in all individuals with psoriasis. The combination of biologic agents with traditional therapies may provide improved therapeutic options for patients who inadequately respond to a single drug or when efficacy may be increased with supplementation of another treatment. In addition, combination therapy may reduce safety concerns and cumulative toxicity, as lower doses of individual agents may be efficacious when used together. This article reviews the current evidence available on the efficacy and safety of combining biologic agents with systemic therapies (methotrexate, cyclosporine, or retinoids) or with phototherapy, and the combination of biologic agents themselves. Guidance is provided to help physicians identify situations and the characteristics of patients who would benefit from combination therapy with a biologic agent. Finally, the potential clinical impact of biologic therapies in development (e.g., those targeting IL-17A, IL-17RA, or IL-23 alone) is analyzed.

  8. The significance of ecology in the development of Verticillium chlamydosporium as a biological agent against root-knot nematodes (Meloidogyne spp.).

    OpenAIRE

    Leij, van der, T.

    1992-01-01

    A thorough understanding of the interactions which occur between nematode parasites and nematode pests and the influence of biotic and abiotic factors on these interactions, is essential in the development of biological control agents for nematodes. The aim of this study was to develop a particular isolate of the nematophagous fungus Verticillium chlamydosporium as a biological control agent for root-knot nematodes. The work has gained insight into some of the key factors which govern the eff...

  9. Conserving and enhancing biological control of nematodes.

    Science.gov (United States)

    Timper, Patricia

    2014-06-01

    Conservation biological control is the modification of the environment or existing practices to protect and enhance antagonistic organisms to reduce damage from pests. This approach to biological control has received insufficient attention compared with inundative applications of microbial antagonists to control nematodes. This review provides examples of how production practices can enhance or diminish biological control of plant-parasitic nematodes and other soilborne pests. Antagonists of nematodes can be enhanced by providing supplementary food sources such as occurs when organic amendments are applied to soil. However, some organic amendments (e.g., manures and plants containing allelopathic compounds) can also be detrimental to nematode antagonists. Plant species and genotype can strongly influence the outcome of biological control. For instance, the susceptibility of the plant to the nematode can determine the effectiveness of control; good hosts will require greater levels of suppression than poor hosts. Plant genotype can also influence the degree of rhizosphere colonization and antibiotic production by antagonists, as well the expression of induced resistance by plants. Production practices such as crop rotation, fallow periods, tillage, and pesticide applications can directly disrupt populations of antagonistic organisms. These practices can also indirectly affect antagonists by reducing their primary nematode host. One of the challenges of conservation biological control is that practices intended to protect or enhance suppression of nematodes may not be effective in all field sites because they are dependent on indigenous antagonists. Ultimately, indicators will need to be identified, such as the presence of particular antagonists, which can guide decisions on where it is practical to use conservation biological control. Antagonists can also be applied to field sites in conjunction with conservation practices to improve the consistency, efficacy, and

  10. Comparative evaluation of two populations of Pseudophilothrips ichini as candidates for biological control of Brazilian peppertree

    Science.gov (United States)

    Brazilian peppertree, Schinus terebinthifolius Raddi (Sapindales: Anacardiaceae) is one of the worst invasive species in Florida. The thrips Pseudophilothrips ichini Hood (Thysanoptera: Phlaeothripidae) is being considered as a potential biological control agent of Brazilian peppertree. Two populati...

  11. Agent Control for Reconfigurable Open Kinematic Chain Manipulators

    Directory of Open Access Journals (Sweden)

    Janez Sluga

    2013-10-01

    Full Text Available This paper presents a method for the autonomous control of differently structured open kinematic chains based on multi-agent system technology. The appropriate level of distributing local autonomy (agents to a manipulative structure is defined, which makes it possible to dynamically change the number, type and structure of manipulative components without modifying their behavioural logic. To achieve fast reconfigurable and scalable manipulative systems, a new multi-agent method is developed for controlling the manipulator kinematics. The new method enables independent manipulator structure from the control system because of its structural and system modularity. The proposed method consists of kinematic equations for use in an agent environment, agent motion-planning algorithms, evaluation functions, agent control logic and kinematic algorithms. The results of simulations and real- world experiments demonstrate the usefulness of the approach for different non-redundant and redundant manipulation structures.

  12. A Biologically Inspired Cooperative Multi-Robot Control Architecture

    Science.gov (United States)

    Howsman, Tom; Craft, Mike; ONeil, Daniel; Howell, Joe T. (Technical Monitor)

    2002-01-01

    A prototype cooperative multi-robot control architecture suitable for the eventual construction of large space structures has been developed. In nature, there are numerous examples of complex architectures constructed by relatively simple insects, such as termites and wasps, which cooperatively assemble their nests. The prototype control architecture emulates this biological model. Actions of each of the autonomous robotic construction agents are only indirectly coordinated, thus mimicking the distributed construction processes of various social insects. The robotic construction agents perform their primary duties stigmergically i.e., without direct inter-agent communication and without a preprogrammed global blueprint of the final design. Communication and coordination between individual agents occurs indirectly through the sensed modifications that each agent makes to the structure. The global stigmergic building algorithm prototyped during the initial research assumes that the robotic builders only perceive the current state of the structure under construction. Simulation studies have established that an idealized form of the proposed architecture was indeed capable of producing representative large space structures with autonomous robots. This paper will explore the construction simulations in order to illustrate the multi-robot control architecture.

  13. The potential of TaqMan Array Cards for detection of multiple biological agents by real-time PCR.

    Directory of Open Access Journals (Sweden)

    Phillip A Rachwal

    Full Text Available The TaqMan Array Card architecture, normally used for gene expression studies, was evaluated for its potential to detect multiple bacterial agents by real-time PCR. Ten PCR assays targeting five biological agents (Bacillus anthracis, Burkholderia mallei, Burkholderia pseudomallei, Francisella tularensis, and Yersinia pestis were incorporated onto Array Cards. A comparison of PCR performance of each PCR in Array Card and singleplex format was conducted using DNA extracted from pure bacterial cultures. When 100 fg of agent DNA was added to Array Card channels the following levels of agent detection (where at least one agent PCR replicate returned a positive result were observed: Y. pestis 100%, B. mallei & F. tularensis 93%; B. anthracis 71%; B. pseudomallei 43%. For B. mallei & pseudomallei detection the BPM2 PCR, which detects both species, outperformed PCR assays specific to each organism indicating identification of the respective species would not be reproducible at the 100 fg level. Near 100% levels of detection were observed when 100 fg of DNA was added to each PCR in singleplex format with singleplex PCRs also returning sporadic positives at the 10 fg per PCR level. Before evaluating the use of Array Cards for the testing of environmental and clinical sample types, with potential levels of background DNA and PCR inhibitors, users would therefore have to accept a 10-fold reduction in sensitivity of PCR assays on the Array Card format, in order to benefit for the capacity to test multiple samples for multiple agents. A two PCR per agent strategy would allow the testing of 7 samples for the presence of 11 biological agents or 3 samples for 23 biological agents per card (with negative control channels.

  14. Fluctuation-Enhanced Sensing for Biological Agent Detection and Identification

    CERN Document Server

    Kish, Laszlo B; King, Maria D; Kwan, Chiman; Jensen, James O; Schmera, Gabor; Smulko, Janusz; Gingl, Zoltan; Granqvist, Claes G

    2009-01-01

    We survey and show our earlier results about three different ways of fluctuation-enhanced sensing of bio agent, the phage-based method for bacterium detection published earlier; sensing and evaluating the bacterial odors; and spectral and amplitude distribution analysis of noise in light scattering to identify spores based on their diffusion coefficient.

  15. Biological in situ characterization of polymeric microbubble contrast agents

    NARCIS (Netherlands)

    Wan, Sha; Egri, Gabriella; Oddo, Letizia; Cerroni, Barbara; Dähne, Lars; Paradossi, Gaio; Salvati, Anna; Lynch, Iseult; Dawson, Kenneth A; Monopoli, Marco P

    2016-01-01

    Polymeric microbubbles (MBs) are gas filled particles composed of a thin stabilized polymer shell that have been recently developed as valid contrast agents for the combined use of ultrasonography (US), magnetic resonance imaging (MRI) and single photon emission computer tomography (SPECT) imaging.

  16. Automated multi-objective calibration of biological agent-based simulations.

    Science.gov (United States)

    Read, Mark N; Alden, Kieran; Rose, Louis M; Timmis, Jon

    2016-09-01

    Computational agent-based simulation (ABS) is increasingly used to complement laboratory techniques in advancing our understanding of biological systems. Calibration, the identification of parameter values that align simulation with biological behaviours, becomes challenging as increasingly complex biological domains are simulated. Complex domains cannot be characterized by single metrics alone, rendering simulation calibration a fundamentally multi-metric optimization problem that typical calibration techniques cannot handle. Yet calibration is an essential activity in simulation-based science; the baseline calibration forms a control for subsequent experimentation and hence is fundamental in the interpretation of results. Here, we develop and showcase a method, built around multi-objective optimization, for calibrating ABSs against complex target behaviours requiring several metrics (termed objectives) to characterize. Multi-objective calibration (MOC) delivers those sets of parameter values representing optimal trade-offs in simulation performance against each metric, in the form of a Pareto front. We use MOC to calibrate a well-understood immunological simulation against both established a priori and previously unestablished target behaviours. Furthermore, we show that simulation-borne conclusions are broadly, but not entirely, robust to adopting baseline parameter values from different extremes of the Pareto front, highlighting the importance of MOC's identification of numerous calibration solutions. We devise a method for detecting overfitting in a multi-objective context, not previously possible, used to save computational effort by terminating MOC when no improved solutions will be found. MOC can significantly impact biological simulation, adding rigour to and speeding up an otherwise time-consuming calibration process and highlighting inappropriate biological capture by simulations that cannot be well calibrated. As such, it produces more accurate

  17. Agent Based Control of Electric Power Systems with Distributed Generation

    DEFF Research Database (Denmark)

    Saleem, Arshad

    . The methodology consists of suggestions for redesign of control architecture, a prototype for a software platform which facilitates implementation of multiagent control and results from case studies of specic scenarios. The work also contributes to agent based control with an approach of model based agents....... This thesis focuses on making a systematic evaluation of using intelligent software agent technology for control of electric power systems with high penetration of distributed generation. The thesis is based upon a requirement driven approach. It starts with investigating new trends and challenges in Electric...... agents. It suggests a multiagent based exible control architecture (subgrid control) suitable for the implementation of the innovative control concepts. This subgrid control architecture is tested on a novel distributed software platform which has been developed to design, test and evaluate distributed...

  18. AFECS. Multi-Agent Framework for Experiment Control Systems

    Energy Technology Data Exchange (ETDEWEB)

    Vardan Gyurjyan; David Abbott; William Heyes; Edward Jastrzembski; Carl Timmer; Elliott Wolin

    2008-01-23

    AFECS is a pure Java based software framework for designing and implementing distributed control systems. AFECS creates a control system environment as a collection of software agents behaving as finite state machines. These agents can represent real entities, such as hardware devices, software tasks, or control subsystems. A special control oriented ontology language (COOL), based on RDFS (Resource Definition Framework Schema) is provided for control system description as well as for agent communication. AFECS agents can be distributed over a variety of platforms. Agents communicate with their associated physical components using range of communication protocols, including tcl-DP, cMsg (publish-subscribe communication system developed at Jefferson Lab), SNMP (simple network management protocol), EPICS channel access protocol and JDBC.

  19. AFECS. multi-agent framework for experiment control systems

    Energy Technology Data Exchange (ETDEWEB)

    Gyurjyan, V; Abbott, D; Heyes, G; Jastrzembski, E; Timmer, C; Wolin, E [Jefferson Lab, 12000 Jefferson Ave. MS-12B3, Newport News, VA 23606 (United States)], E-mail: gurjyan@jlab.org

    2008-07-01

    AFECS is a pure Java based software framework for designing and implementing distributed control systems. AFECS creates a control system environment as a collection of software agents behaving as finite state machines. These agents can represent real entities, such as hardware devices, software tasks, or control subsystems. A special control oriented ontology language (COOL), based on RDFS (Resource Definition Framework Schema) is provided for control system description as well as for agent communication. AFECS agents can be distributed over a variety of platforms. Agents communicate with their associated physical components using range of communication protocols, including tcl-DP, cMsg (publish-subscribe communication system developed at Jefferson Lab), SNMP (simple network management protocol), EPICS channel access protocol and JDBC.

  20. Combining biological agents and chemotherapy in the treatment of cholangiocarcinoma

    DEFF Research Database (Denmark)

    Jensen, Lars Henrik; Jakobsen, Anders

    2011-01-01

    is not always possible. Chemotherapy is effective and the combination of cisplatin and gemcitabine is considered a standard treatment of inoperable cholangiocarcinoma. Biological targeted treatment to date has minor effect when given as monotherapy, but some of the drugs hold promise as an adjunct...... to chemotherapy. It should, however, be noted that most of the trials are based on few patients, and thus far the literature does not allow for a conclusion as to the role of biological treatment on cholangiocarcinoma. This situation calls for well-designed randomized trials, and international cooperation as well...

  1. TRIAZOLE: A POTENTIAL BIOACTIVE AGENT (SYNTHESIS AND BIOLOGICAL ACTIVITY)

    OpenAIRE

    Pandeya Surendra Nath; Pathak Ashish; Mishra Rupesh

    2011-01-01

    Azoles belong to very important class of Antimicrobial drugs. Triazole is very important Azole which exists in two isomeric forms namely 1, 2, 3-Triazole and 1, 2, 4-Triazole. This Review Article covers the Different approaches to synthesize Triazoles having different substitution and their different biological activity. This Review article can be useful to synthesize new compounds having Triazole nucleolus.

  2. Rheumatoid Arthritis Patients after Initiation of a New Biologic Agent

    DEFF Research Database (Denmark)

    Courvoisier, D S; Alpizar-Rodriguez, D; Gottenberg, J E;

    2016-01-01

    BACKGROUND: Response to disease modifying antirheumatic drugs (DMARDs) in rheumatoid arthritis (RA) is often heterogeneous. We aimed to identify types of disease activity trajectories following the initiation of a new biologic DMARD (bDMARD). METHODS: Pooled analysis of nine national registries...

  3. Optimization of Graphene Sensors to Detect Biological Warfare Agents

    Science.gov (United States)

    2014-03-27

    when treated with antibiotics. Untreated, it has a mortality rate between 80% and 100%. The 1979 Sverdlovsk Incident in Russia resulted in...Insights Into How Terrorists Develop Biological and Chemical Weapons,” Washington D.C., 2011. [5] N. C. F. Biotechnology Information, “Bacillus

  4. Integrating the Agents of Bioterrorism into the General Biology Curriculum: II. Mode of Action of the Biological Agents.

    Science.gov (United States)

    Pommerville, Jeffrey C.

    2003-01-01

    Integrates bioterrorism into the science curriculum and explains actions against serious agents such as anthrax, plague, smallpox, botulinum toxin, and ricin toxin. Uses the learning cycle as the instructional tool which is student-centered and has three phases that include exploring, explaining, and extending. (Contains 24 references.) (YDS)

  5. Controlled ecological life support system - biological problems

    Science.gov (United States)

    Moore, B., III (Editor); Macelroy, R. D. (Editor)

    1982-01-01

    The general processes and controls associated with two distinct experimental paradigms are examined. Specific areas for research related to biotic production (food production) and biotic decomposition (waste management) are explored. The workshop discussions were directed toward Elemental cycles and the biological factors that affect the transformations of nutrients into food, of food material into waste, and of waste into nutrients were discussed. To focus on biological issues, the discussion assumed that (1) food production would be by biological means (thus excluding chemical synthesis), (2) energy would not be a limiting factor, and (3) engineering capacity for composition and leak rate would be adequate.

  6. Design of the Agent-based Intelligent Control System

    Directory of Open Access Journals (Sweden)

    Baltazár Frankovič

    2005-11-01

    Full Text Available This paper introduces the possibilities of multi-agent system application for themodeling and intelligent control in the case of coarse ceramics burning process. It consistsof technological description of this process, its decomposition into agents and macro-modelof the decision system. Then multi-agent system modeling tools, such as alternating-timetemporal logic and alternating transition systems and their epistemic extensions, arepresented.

  7. A short history of anti-rheumatic therapy - VII. Biological agents

    Directory of Open Access Journals (Sweden)

    B. Gatto

    2011-11-01

    Full Text Available The introduction of biological agents has been a major turning-point in the treatment of rheumatic diseases, particularly in rheumatoid arthritis. This review describes the principle milestones that have led, through the knowledge of the structure and functions of nucleic acids, to the development of production techniques of the three major families of biological agents: proteins, monoclonal antibodies and fusion proteins. A brief history has also been traced of the cytokines most involved in the pathogenesis of inflammatory rheumatic diseases (IL-1 and TNF and the steps which have led to the use of the main biological drugs in rheumatology: anakinra, infliximab, adalimumab, etanercept and rituximab.

  8. Bioprospecting endophytic bacteria for biological control of coffee leaf rust Bioprospecção de bactérias endofíticas como agentes de biocontrole da ferrugem do cafeeiro

    Directory of Open Access Journals (Sweden)

    Humberto Franco Shiomi

    2006-02-01

    Full Text Available Suppression of plant diseases due to the action of endophytic microorganisms has been demonstrated in several pathosystems. Experiments under controlled conditions involving endophytic bacteria isolated from leaves and branches of Coffea arabica L and Coffea robusta L were conducted with the objective of evaluating the inhibition of germination of Hemileia vastatrix Berk. & Br., race II, urediniospores and the control of coffee leaf rust development in tests with leaf discs, detached leaves, and on potted seedling of cv. Mundo Novo. The endophytic bacterial isolates tested proved to be effective in inhibiting urediniospore germination and/or rust development, with values above 50%, although the results obtained in urediniospore germination tests were inferior to the treatment with fungicide propiconazole. Endophytic isolates TG4-Ia, TF2-IIc, TF9-Ia, TG11-IIa, and TF7-IIa, demonstrated better coffee leaf rust control in leaf discs, detached leaves, and coffee plant tests. The endophytic isolates TG4-Ia and TF9-Ia were identified as Bacillus lentimorbus Dutky and Bacillus cereus Frank. & Frank., respectively. Some endophytic bacterial isolates were effective in controlling the coffee leaf rust, although some increased the severity of the disease. Even though a relatively small number of endophytic bacteria were tested, promising results were obtained regarding the efficiency of coffee leaf rust biocontrol. These selected agents appears to be an alternative for future replacement of chemical fungicide.Supressão de doenças de plantas por microrganismos endofíticos tem sido demonstrada em diversos patossistemas. Neste trabalho foram selecionados isolados de bactérias endofíticas de folhas e ramos de cafeeiro com potencial para o controle biológico da ferrugem do cafeeiro, pois é conhecido que esses microrganismos podem possuir essa característica. Bactérias endofíticas isoladas previamente de folhas e ramos de Coffea arabica L e Coffea

  9. Synthesis and Biological Evaluation of Hydrazone Derivatives as Antifungal Agents

    Directory of Open Access Journals (Sweden)

    Bruna B. Casanova

    2015-05-01

    Full Text Available Emerging yeasts are among the most prevalent causes of systemic infections with high mortality rates and there is an urgent need to develop specific, effective and non-toxic antifungal agents to respond to this issue. In this study 35 aldehydes, hydrazones and hydrazines were obtained and their antifungal activity was evaluated against Candida species (C. parapsilosis, C. tropicalis, C. krusei, C. albicans, C. glabrata and C. lusitaneae and Trichosporon asahii, in an in vitro screening. The minimum inhibitory concentrations (MICs of the active compounds in the screening was determined against 10 clinical isolates of C. parapsilosis and 10 of T. asahii. The compounds 4-pyridin-2-ylbenzaldehyde] (13a and tert-butyl-(2Z-2-(3,4,5-trihydroxybenzylidinehydrazine carboxylate (7b showed the most promising MIC values in the range of 16–32 μg/mL and 8–16 μg/mL, respectively. The compounds’ action on the stability of the cell membrane and cell wall was evaluated, which suggested the action of the compounds on the fungal cell membrane. Cell viability of leukocytes and an alkaline comet assay were performed to evaluate the cytotoxicity. Compound 13a was not cytotoxic at the active concentrations. These results support the discovery of promising candidates for the development of new antifungal agents.

  10. Diabetes Insipidus as a Complication of Wegener's Granulomatosis and Its Treatment with Biologic Agents

    Directory of Open Access Journals (Sweden)

    Joanna Rosalind Cunnington

    2009-01-01

    Full Text Available Wegener's granulomatosis of the pituitary gland resulting in diabetes insipidus is a rare complication of the disease. Standard treatment for Wegener's granulomatosis involves a combination of prednisolone and cylophosphamide, however biologic agents are now being used in refractory cases. We report three cases of patients with diabetes insipidus as a complication of Wegener's granulomatosis who were treated with biologic agents. All three cases showed clinical response to treatment with biologic agents including rituximab and alemtuzumab and two cases demonstrated improvement in pituitary gland abnormalities by MRI. Clinicians should be aware that diabetes insipidus can present as a complication of Wegener's granulomatosis and that biologic therapies may be effective in refractory cases.

  11. Access Control for Agent-based Computing: A Distributed Approach.

    Science.gov (United States)

    Antonopoulos, Nick; Koukoumpetsos, Kyriakos; Shafarenko, Alex

    2001-01-01

    Discusses the mobile software agent paradigm that provides a foundation for the development of high performance distributed applications and presents a simple, distributed access control architecture based on the concept of distributed, active authorization entities (lock cells), any combination of which can be referenced by an agent to provide…

  12. The biology and chemistry of antifungal agents: a review.

    Science.gov (United States)

    Kathiravan, Muthu K; Salake, Amol B; Chothe, Aparna S; Dudhe, Prashik B; Watode, Rahul P; Mukta, Maheshwar S; Gadhwe, Sandeep

    2012-10-01

    In recent years their has been an increased use of antifungal agents and has resulted in the development of resistance to drugs. Currently, use of standard antifungal therapies can be limited because of toxicity, low efficacy rates. Different types of mechanisms contribute to the development of resistance to antifungals. This has given raise to search for a new heterocycle with distinct action or multitargeted combination therapy. This review addresses the areas such as the underlying mechanisms, eight different targets such as ergosterol synthesis, chitin synthesis, ergosterol disruptors, glucan synthesis, squalene epoxidase, nucleic acid synthesis, protein synthesis, microtubules synthesis. The clinically employed drugs along with the current research work going on worldwide on different heterocycles are discussed. In recent advances various heterocycles including imidazole, benzimidazole etc., twenty three scaffolds and their lead identification are discussed.

  13. INTEGRATED MANAGEMENT OF CHROMOLAENA ODORATA EMPHASIZING THE CLASSICAL BIOLOGICAL CONTROL

    Directory of Open Access Journals (Sweden)

    SOEKISMAN TJITROSEMITO

    1998-01-01

    Full Text Available Chromolaena odorata, Siam weed, a very important weed of Java Island (Indonesia is native to Central and South America. In the laboratory it showed rapid growth (1.15 g/g/week in the first 8 weeks of its growth. The biomass was mainly as leaves (LAR : 317.50 cm'/g total weight. It slowed down in the following month as the biomass was utilized for stem and branch formation. This behavior supported the growth of C. odorata into a very dense stand. It flowered, fruited during the dry season, and senesced following maturation of seeds from inflorescence branches. These branches dried out, but soon the stem resumed aggressive growth following the wet season. Leaf biomass was affected by the size of the stem in its early phase of regrowth, but later on it was more affected by the number of branches. The introduction of Pareuchaetes pseudoinsulata to Indonesia, was successful only in North Sumatera. In Java it has not been reported to establish succesfully. The introduction of another biological control agent, Procecidochares conneca to Indonesia was shown to be sp ecific and upon release in West Java it established immediately. It spread exponentia lly in the first 6 months of its release. Field monitoring continues to eval uate the impact of the agents. Other biocontrol agents (Actmole anteas and Conotrachelus wilt be introduced to Indonesia in 1997 through ACIAR Project on the Biological Control of Chromolaena odorata in Indonesia and Papua New Guinea.

  14. H∞ CONTROL OF NETWORKED MULTI-AGENT SYSTEMS

    Institute of Scientific and Technical Information of China (English)

    Zhongkui LI; Zhisheng DUAN; Lin HUANG

    2009-01-01

    This paper concerns the disturbance rejection problem arising in the coordination control of a group of autonomous agents subject to external disturbances. The agent network is said to possess a desired level of disturbance rejection, if the H∞ norm of its transfer function matrix from the disturbance to the controlled output is satisfactorily small. Undirected graph is used to represent the information flow topology among agents. It is shown that the disturbance rejection problem of an agent network can be solved by analyzing the H∞ control problem of a set of independent systems whose dimensions are equal to that of a single node. An interesting result is that the disturbance rejection ability of the whole agent network coupled via feedback of merely relative measurements between agents will never be better than that of an isolated agent. To improve this, local feedback injections are applied to a small fraction of the agents in the network. Some criteria for possible performance improvement are derived in terms of linear matrix inequalities. Finally, extensions to the case when communication time delays exist are also discussed.

  15. Biopesticides: An option for the biological pest control

    Directory of Open Access Journals (Sweden)

    Eusebio Nava Pérez

    2012-09-01

    Full Text Available The indiscriminate use of synthetic pesticides and the problems that its cause to human health, agriculture and the environment is comment, this paper also present general aspects about of biopesticides, and their uses in the biological pest control. By the nature these can be safely used in a sustainable agriculture. An example is the use of botanical pesticides whose active ingredient are the terpenes, alkaloids and phenolics, these have insecticide effects for many agriculture pests; also its are less expensive, are biodegradable and safe for humans and the environment, however havelittle residuality. Microbial pesticides are being introduced successfully to pests control in important crops such as; coffee, sugar cane, beans and corn. These products contain bacteria, fungi, viruses or nematodes. However, few entomopathogenic agents have been developed as effective biocontrol agents, one of them is the bacterium Bacillus thuringiensis (Berlinier for control of armyworm Spodoptera frugiperda (J.E Smith covering about 74% of the market,fungus 10% , viruses 5% and 11% others. Other upstanding case is the use of the fungus Beauveria bassiana (Balsamoagainst bean weevil Acanthoscelides obtectus (Say. Biopesticides have shown that when are used properly in the biological pest control its favor the practice of a sustainable agriculture, with less dependence of chemical insecticides.

  16. Biological Control of Nematodes with Bacteria

    Science.gov (United States)

    Biological control of nematodes is receiving increased attention as environmental considerations with the use of nematicides have increased in importance and their high cost prohibits use on many crops. In addition, nematode resistant cultivars are not available for many crops and resistance that i...

  17. Probiotics as Control Agents in Aquaculture

    Institute of Scientific and Technical Information of China (English)

    Gómez R. Geovanny D; Balcázar José Luis; MA Shen

    2007-01-01

    Infectious diseases constitute a limiting factor in the development of the aquaculture production, and control has solely concentrated on the use of antibiotics. However, the massive use of antibiotics for the control of diseases has been questioned by acquisition of antibiotic resistance and the need of alternative is of prime importance. Probiotics, live microorganisms administered in adequate amounts that confer a healthy effect on the host, are emerging as significant microbial food supplements in the field of prophylaxis.

  18. Probiotics as control agents in aquaculture

    Science.gov (United States)

    Geovanny D, Gómez R.; Balcázar, José Luis; Ma, Shen

    2007-01-01

    Infectious diseases constitute a limiting factor in the development of the aquaculture production, and control has solely concentrated on the use of antibiotics. However, the massive use of antibiotics for the control of diseases has been questioned by acquisition of antibiotic resistance and the need of alternative is of prime importance. Probiotics, live microorganisms administered in adequate amounts that confer a healthy effect on the host, are emerging as significant microbial food supplements in the field of prophylaxis.

  19. Berthing control with multi-agent system; Multi agent system ni yoru chakusan seigyo

    Energy Technology Data Exchange (ETDEWEB)

    Ito, H. [Tokyo Univ. (Japan)

    1998-12-31

    The berthing of a ship is a kind of control operations of position, speed and direction of a ship in order to bring a ship alongside a quay. Berthing control is accompanied with a hard problem in which the 6 freedoms of position and speed in 3 directions such as fore and behind, right and left and a revolution must be controlled. In this study, a concept of the agent was introduced as a means of berthing. The agent is a computer program which can be worked in a person`s place. If an autonomous intelligence is carried on each element such as a tugboat or a propeller of ship, the element is able to act based on judgement decided by itself without an instruction from a control center. Thereby, the berthing control system as a multi-agent system having an adaptability and a cooperativeness will be realized. Then the multi-agent system to help berthing was constructed by applying the Muller`s three phase model as a cooperative autonomous agent and by sharing the role of each phase. 8 refs., 12 figs., 1 tab.

  20. Biological control of aflatoxin contamination of crops

    Institute of Scientific and Technical Information of China (English)

    Yan-ni YIN; Lei-yan YAN; Jin-hua JIANG; Zhong-hua MA

    2008-01-01

    Aflatoxins produced primarily by two closely related fungi, Aspergillus flavus and Aspergillus parasiticus, are mutagenic and carcinogenic in animals and humans. Of many approaches investigated to manage aflatoxin contamination, biological control method has shown great promise. Numerous organisms, including bacteria, yeasts and nontoxigenic fungal strains of A.flavus and A. parasiticus, have been tested for their ability in controlling aflatoxin contamination. Great successes in reducing aflatoxin contamination have been achieved by application of nontoxigenic strains of A. flavus and A. parasiticus in fields of cotton, peanut, maize and pistachio. The nontoxigenic strains applied to soil occupy the same niches as the natural occurring toxigenic strains. They, therefore, are capable of competing and displacing toxigenic strains. In this paper, we review recent development in biological control of aflatoxin contamination.

  1. Supervisory Control of Fuzzy Discrete Event Systems Based on Agent

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    FDES (fuzzy discrete event systems) can effectively represent a kind of complicated systems involving deterministic uncertainties and vagueness as well as human subjective observation and judgement from the view of discrete events, here the information system is divided into some independent intelligent entitative Agents. The concept of information processing state based on Agents was proposed. The processing state of Agent can be judged by some assistant observation parameters about the Agent and its environment around, and the transition among these states can be represented by FDES based on rules. In order to ensure the harmony of the Agents for information processing, its upstream and downstream buffers are considered in the modeling of the Agent system,and the supervisory controller based on FDES is constructed. The processing state of Agent can be adjusted by the supervisory controller to improve the stability of the system and the efficiency of resource utilization during the process according to the control policies. The result of its application was provided to illustrate the validity of the supervisory adjustment.

  2. Agentes Biológicos en el tratamiento de la Artritis Reumatoide Biological Agents in the Treatment of Rheumatoid Arthritis

    Directory of Open Access Journals (Sweden)

    José Francisco Díaz-Coto

    2011-02-01

    Full Text Available El mayor conocimiento inmuno-patológico de la artritis reumatoide permitió mediante una sofisticada tecnología molecular elaborar antagonistas contra blancos específicos en diversos pasos de la inmuno patogenia de la enfermedad. Existe una amplia evidencia sobre la eficacia, tolerabilidad y seguridad de estos agentes en diferentes escenarios clínicos de la artritis reumatoide. La introducción de estos agentes biológicos en el arsenal terapéutico de la artritis reumatoide ha marcado un hito en su evolución y pronóstico artritis reumatoide.A better understanding of the immuno-pathological rheumatoid arthritis enabled by sophisticated molecular technology to develop antagonists against specific targets in various steps of the immune pathogenesis of the disease. There is ample evidence on the efficacy, tolerability and safety of these agents in different clinical scenarios of rheumatoid arthritis. The introduction of biological agents in the armamentarium of rheumatoid arthritis has marked a milestone in its evolution and prognosis rheumatoid arthritis.

  3. Cardiometabolic risk in psoriasis: differential effects of biologic agents

    Directory of Open Access Journals (Sweden)

    Mariana J Kaplan

    2008-12-01

    Full Text Available Mariana J KaplanDepartment of Internal Medicine, University of Michigan Medical School, Ann Arbor, Michigan, USAAbstract: Psoriasis is associated to an increased risk of cardiovascular (CV complications. Overall, the pathogenic mechanisms involved in premature CV complications in psoriasis appear to be complex and multifactorial, with traditional and nontraditional risk factors possibly contributing to the increased risk. Based on what is known about the pathogenesis of psoriasis and extrapolating the current knowledge on CV complications in other inflammatory diseases, studies are needed to investigate if appropriate control of the inflammatory, immunologic and metabolic disturbances present in psoriasis can prevent the development of this potentially lethal complication. It is clear that there is a great need for heightened awareness of the increased risk for vascular damage in patients with psoriasis. It is also crucial to closely monitor patients with psoriasis for CV risk factors including obesity, hypertension, diabetes, and hyperlipidemia. Whether treatment regimens that effectively manage systemic inflammation will lead to prevention of CV complications in psoriasis needs to be investigated. Clearly, studies should focus on establishing the exact mechanisms that determine CV risk in psoriasis so that appropriate preventive strategies and treatment guidelines can be established.Keywords: psoriasis, atherosclerosis, inflammation, vascular

  4. Illusory versus genuine control in agent-based games

    Science.gov (United States)

    Satinover, J. B.; Sornette, D.

    2009-02-01

    In the Minority, Majority and Dollar Games (MG, MAJG, G) agents compete for rewards, acting in accord with the previously best-performing of their strategies. Different aspects/kinds of real-world markets are modelled by these games. In the MG, agents compete for scarce resources; in the MAJG agents imitate the group to exploit a trend; in the G agents attempt to predict and benefit both from trends and changes in the direction of a market. It has been previously shown that in the MG for a reasonable number of preliminary time steps preceding equilibrium (Time Horizon MG, THMG), agents’ attempt to optimize their gains by active strategy selection is “illusory”: the hypothetical gains of their strategies is greater on average than agents’ actual average gains. Furthermore, if a small proportion of agents deliberately choose and act in accord with their seemingly worst performing strategy, these outperform all other agents on average, and even attain mean positive gain, otherwise rare for agents in the MG. This latter phenomenon raises the question as to how well the optimization procedure works in the THMAJG and THG. We demonstrate that the illusion of control is absent in THMAJG and THG. This provides further clarification of the kinds of situations subject to genuine control, and those not, in set-ups a priori defined to emphasize the importance of optimization.

  5. [Incorporation of controlling dengue by community health agent].

    Science.gov (United States)

    Cazola, Luiza Helena de Oliveira; Tamaki, Edson Mamoru; Pontes, Elenir Rose Jardim Cury

    2014-01-01

    The purpose of this study was to identify self-perceived differences in the work processes of community health agents (CHA) in two counties of Mato Grosso do Sul, regarding dengue control and Family Health Strategy (FHS) activities. Structured interviews were applied to 57 CHA. The subjects had similar sociodemographic characteristics. Agents in Rio Verde de Mato Grosso county, who performed only FHS tasks, failed to complete essential data of the Form A. In São Gabriel do Oeste county, CHA currently perform tasks pertaining to dengue fever control, previously conducted by Endemic Disease Control Agents (now abolished), while in Rio Verde de Mato Grosso county, dengue control remained assigned to the latter group. In São Gabriel do Oeste county, CHA did not view the double workload of two programs as affecting their professional productivity. The pooling of tasks from the two programs proved to be feasible, with no detrimental effects on performance.

  6. Initial impacts and field validation of host range for Boreioglycaspis melaleucae Moore (Hemiptera: Psyllidae),a biological control agent of the invasive tree Melaleuca quinquenervia (Cav.) Blake (Myrtales: Myrtaceae: Leptosp

    Science.gov (United States)

    Invasion of south Florida wetlands by the Australian paperbark tree (“melaleuca”), Melaleuca quinquenervia (Cav.) S.T. Blake (melaleuca) has caused adverse economic and environmental impacts. The tree’s biological attributes along with favorable ambient biophysical conditions combine to complicate ...

  7. Biological control of pests and insects. (Latest citations from the NTIS bibliographic database). Published Search

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-04-01

    The bibliography contains citations concerning the use of biological agents to control insects and pests. Radiation, genetic breeding, bacteria, fungi, viruses, and pheromones are discussed as alternatives to pesticidal management. Methods for monitoring the effectiveness and environmental impact of these agents are reviewed. Population control of fruit flies, spruce sawflies, flies, mosquitoes, cockroaches, gypsy moths, and other agriculturally-important insects is also discussed. (Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

  8. Biological control of pests and insects. (Latest citations from the NTIS bibliographic database). Published Search

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-02-01

    The bibliography contains citations concerning the use of biological agents to control insects and pests. Radiation, genetic breeding, bacteria, fungi, viruses, and pheromones are discussed as alternatives to pesticidal management. Methods for monitoring the effectiveness and environmental impact of these agents are reviewed. Population control of fruit flies, spruce sawflies, flies, mosquitoes, cockroaches, gypsy moths, and other agriculturally-important insects is also discussed. (Contains a minimum of 190 citations and includes a subject term index and title list.)

  9. The architectural foundations for agent-based shop floor control

    DEFF Research Database (Denmark)

    Langer, Gilad; Bilberg, Arne

    1998-01-01

    simulation and cell controlenabling technologies. In order to continuethis research effortnew concepts and theories for shop floor control are investigated.This paper reviews the multi-agent concept aimed at investigatingits potential use in shop floor control systems. The paper willalso include a survey...

  10. Aschersonia aleyrodis as a microbial control agent of greenhouse whitefly.

    NARCIS (Netherlands)

    Fransen, J.J.

    1987-01-01

    Various aspects of the development of the entomopathogenic fungus Aschersoniaaleyrodis as a control agent of greenhouse whitefly, Trialeurodesvaporariorum , were investigated. For control of greenhouse whitefly in tomato crops the parasitoid Encarsiaformosa

  11. A theoretical framework for biological control of soil-borne plant pathogens: Identifying effective strategies.

    Science.gov (United States)

    Cunniffe, Nik J; Gilligan, Christopher A

    2011-06-07

    We develop and analyse a flexible compartmental model of the interaction between a plant host, a soil-borne pathogen and a microbial antagonist, for use in optimising biological control. By extracting invasion and persistence thresholds of host, pathogen and biological control agent, performing an equilibrium analysis, and numerical investigation of sensitivity to parameters and initial conditions, we determine criteria for successful biological control. We identify conditions for biological control (i) to prevent a pathogen entering a system, (ii) to eradicate a pathogen that is already present and, if that is not possible, (iii) to reduce the density of the pathogen. Control depends upon the epidemiology of the pathogen and how efficiently the antagonist can colonise particular habitats (i.e. healthy tissue, infected tissue and/or soil-borne inoculum). A sharp transition between totally effective control (i.e. eradication of the pathogen) and totally ineffective control can follow slight changes in biologically interpretable parameters or to the initial amounts of pathogen and biological control agent present. Effective biological control requires careful matching of antagonists to pathosystems. For preventative/eradicative control, antagonists must colonise susceptible hosts. However, for reduction in disease prevalence, the range of habitat is less important than the antagonist's bulking-up efficiency.

  12. Onchocerciasis control: biological research is still needed

    Directory of Open Access Journals (Sweden)

    Boussinesq M.

    2008-09-01

    Full Text Available Achievements obtained by the onchocerciasis control programmes should not lead to a relaxation in the biological research on Onchocerca volvulus. Issues such as the Loa loa-related postivermectin serious adverse events, the uncertainties as to whether onchocerciasis can be eliminated by ivermectin treatments, and the possible emergence of ivermectin-resistant O. volvulus populations should be addressed proactively. Doxycycline, moxidectin and emodepside appear to be promising as alternative drugs against onchocerciasis but support to researches in immunology and genomics should also be increased to develop new control tools, including both vaccines and macrofilaricidal drugs.

  13. A support vector machine approach to the automatic identification of fluorescence spectra emitted by biological agents

    Science.gov (United States)

    Gelfusa, M.; Murari, A.; Lungaroni, M.; Malizia, A.; Parracino, S.; Peluso, E.; Cenciarelli, O.; Carestia, M.; Pizzoferrato, R.; Vega, J.; Gaudio, P.

    2016-10-01

    Two of the major new concerns of modern societies are biosecurity and biosafety. Several biological agents (BAs) such as toxins, bacteria, viruses, fungi and parasites are able to cause damage to living systems either humans, animals or plants. Optical techniques, in particular LIght Detection And Ranging (LIDAR), based on the transmission of laser pulses and analysis of the return signals, can be successfully applied to monitoring the release of biological agents into the atmosphere. It is well known that most of biological agents tend to emit specific fluorescence spectra, which in principle allow their detection and identification, if excited by light of the appropriate wavelength. For these reasons, the detection of the UVLight Induced Fluorescence (UV-LIF) emitted by BAs is particularly promising. On the other hand, the stand-off detection of BAs poses a series of challenging issues; one of the most severe is the automatic discrimination between various agents which emit very similar fluorescence spectra. In this paper, a new data analysis method, based on a combination of advanced filtering techniques and Support Vector Machines, is described. The proposed approach covers all the aspects of the data analysis process, from filtering and denoising to automatic recognition of the agents. A systematic series of numerical tests has been performed to assess the potential and limits of the proposed methodology. The first investigations of experimental data have already given very encouraging results.

  14. From Here to Autonomicity: Self-Managing Agents and the Biological Metaphors that Inspire Them

    Science.gov (United States)

    Sterritt, Roy; Hinchey, Mike

    2005-01-01

    We seek inspiration for self-managing systems from (obviously, pre-existing) biological mechanisms. Autonomic Computing (AC), a self-managing systems initiative based on the biological metaphor of the autonomic nervous system, is increasingly gaining momentum as the way forward for integrating and designing reliable systems, while agent technologies have been identified as a key enabler for engineering autonomicity in systems. This paper looks at other biological metaphors such as reflex and healing, heart- beat monitors, pulse monitors and apoptosis for assisting in the realization of autonomicity.

  15. Efficacy and safety of biological agents for systemic juvenile idiopathic arthritis

    DEFF Research Database (Denmark)

    Tarp, Simon; Amarilyo, Gil; Foeldvari, Ivan;

    2016-01-01

    % improvement according to the modified American College of Rheumatology Paediatric 30 response criteria (JIA ACR30). The primary safety outcome was defined as serious adverse events (SAEs). Outcomes were analysed by pairwise and network meta-analyses. The quality of evidence between biologic agents...

  16. Use of combination of leflunomide with biological agents in treatment of rheumatoid arthritis.

    NARCIS (Netherlands)

    Kalden, J.R.; Antoni, C.; Alvaro-Gracia, J.M.; Combe, B.; Emery, P.; Kremer, J.M.J.; Strand, C.V.; Riel, P.L.C.M. van; Smolen, J.S.

    2005-01-01

    An Expert Panel Meeting was held in May 2004 to assess experience with combination therapy with leflunomide and biological agents in the treatment of rheumatoid arthritis (RA), to identify both optimal use of such combinations and precautions for use. Eleven published prospective or retrospective st

  17. LQR Control for Homogeneous Agents with Multi-graph Topology

    Institute of Scientific and Technical Information of China (English)

    ZHANG Dong-Mei; OU Lin-Lin; MENG Li; WANG Xin-Gang

    2013-01-01

    We consider a set of multi-agent systems (MASs)with general linear time-invariant (LTI) dynamics and a control problem where the performance index couples the behavior of the system.The interconnection topology between the agents is modeled as an undirected multi-graph with self-loop,where each system is a node and the control action at each node is a function of its state and the states of its neighbors.The linear quadratic regulator (LQR) control problem considered in this paper can be regarded as a structure optimization problem due to the block diagonal restriction on the feedback gain.It is shown that minimizing the LQR performance limit of the multiagent system under the distributed controller equals minimizing the sum performance of a single agent system.A sufficient condition is presented in terms of a set of linear matrix inequalities (LMIs) to achieve certain suboptimal performance specifications.In addition to make the control design more applicable,the notion of the LQR performance region is introduced and analyzed,which is shown to be convex with respect to the eigenvalues of the Laplacian matrix.The LQR control of the multi-agent system is then converted to the LQR control of a set of subsystems,which incorporates only two inequality constraints with the minimum and maximum eigenvalues as the coefficients.Numerical examples are presented to illustrate the proposed method.

  18. Compatible biological and chemical control systems for Rhizoctonia solani in potato

    NARCIS (Netherlands)

    Boogert, van den P.H.J.F.; Luttikholt, A.J.G.

    2004-01-01

    A series of chemical and biological control agents were tested for compatibility with the Rhizoctonia-specific biocontrol fungus Verticillium biguttatum aimed at designing novel control strategies for black scurf (Rhizoctonia solani) and other tuber diseases in potato. The efficacy of chemicals, alo

  19. Biological Agents

    Science.gov (United States)

    ... Workers can file a complaint with OSHA by calling 1-800-321-OSHA (6742), online via eComplaint ... to Ensure an Appropriate Response to Anthrax Contamination . Government Accountability Office (GAO) Report GAO-04-239, (September ...

  20. Rotating Biological Contractors (RBC's). Instructor's Guide. Biological Treatment Process Control.

    Science.gov (United States)

    Zickefoose, Charles S.

    This two-lesson unit on rotating biological contactors (RBC's) is designed to be used with students who have had some experience in wastewater treatment and a basic understanding of biological treatment. The first lesson provides information on the concepts and components of RBC treatment systems. The second lesson focuses on design operation and…

  1. Approach for Autonomous Control of Unmanned Aerial Vehicle Using Intelligent Agents for Knowledge Creation

    Science.gov (United States)

    Dufrene, Warren R., Jr.

    2004-01-01

    This paper describes the development of a planned approach for Autonomous operation of an Unmanned Aerial Vehicle (UAV). A Hybrid approach will seek to provide Knowledge Generation through the application of Artificial Intelligence (AI) and Intelligent Agents (IA) for UAV control. The applications of several different types of AI techniques for flight are explored during this research effort. The research concentration is directed to the application of different AI methods within the UAV arena. By evaluating AI and biological system approaches. which include Expert Systems, Neural Networks. Intelligent Agents, Fuzzy Logic, and Complex Adaptive Systems, a new insight may be gained into the benefits of AI and CAS techniques applied to achieving true autonomous operation of these systems. Although flight systems were explored, the benefits should apply to many Unmanned Vehicles such as: Rovers. Ocean Explorers, Robots, and autonomous operation systems. A portion of the flight system is broken down into control agents that represent the intelligent agent approach used in AI. After the completion of a successful approach, a framework for applying an intelligent agent is presented. The initial results from simulation of a security agent for communication are presented.

  2. A PRINCIPAL-AGENT MODEL FOR REGIONAL PEST CONTROL ADOPTION

    OpenAIRE

    Ahouissoussi, Nicolas B.C.

    1995-01-01

    Investigating the underlying producer characteristics associated with regional pest control adoption revealed an interesting proposition. Early adopting producers of firm-specific techniques with characteristics including higher education, more specialized operations, and larger sized business units are dissatisfied with a regional pest control technique. This study provides an explanation of the proposition based on a principal-agent model. Empirical support for the proposition is also prese...

  3. Laboratory Study on Biological Control of Ticks (Acari: Ixodidae) by Entomopathogenic Indigenous Fungi (Beauveria bassiana)

    OpenAIRE

    M Abdigoudarzi; Esmaeilnia, K; Shariat, N

    2009-01-01

    Background: Chemical control method using different acaricides as spray, dipping solution or pour-on is routinely used for controlling ticks. Biological control agents are favorable due to their safety for animals and environment. Entomopathogenic fungi such as Beauveria bassiana are well known for controlling ticks. In this study, two Iranian indigenous strains of B. bassiana (B. bassiana 5197 and B. bassiana Evin) were selected and grown on specific me­dia. The pathogenic effects of the...

  4. Portuguese guidelines for the use of biological agents in rheumatoid arthritis - March 2010 update.

    Science.gov (United States)

    Fonseca, João Eurico; Canhão, Helena; Reis, Paulo; Santos, Maria José; Branco, Jaime; Quintal, Alberto; Malcata, Armando; Araújo, Domingos; Ventura, Francisco; Figueiredo, Guilherme; da Silva, José Canas; Patto, José Vaz; de Queiroz, Mário Viana; Santos, Rui André; Neto, Adriano José; de Matos, Alves de; Rodrigues, Ana; Mourão, Ana Filipa; Ribeiro, Ana Sofia; Cravo, Ana Rita; Barcelos, Anabela; Cardoso, Anabela; Vilar, António; Braña, Arecili; Faustino, Augusto; Silva, Candida; Godinho, Fátima; Cunha, Inês; Costa, José António; Gomes, José António Melo; Pinto, José António Araújo; da Silva, J A Pereira; Miranda, Luís Cunha; Inês, Luís; Santos, Luís Maurício; Cruz, Margarida; Salvador, Maria João; Ferreira, Maria Júlia; Rial, Maria; Bernardes, Miguel; Bogas, Mónica; Araújo, Paula; Machado, Pedro; Pinto, Patrícia; de Melo, Rui Gomes; Cortes, Sara; Alcino, Sérgio; Capela, Susana

    2010-01-01

    The authors present the revised version of the Portuguese Society of Rheumatology (SPR) guidelines for the treatment of rheumatoid arthritis (RA) with biological therapies. In these guidelines the criteria for introduction and maintenance of biological agents are discussed as well as the contraindications and procedures in the case of non-responders. Biological treatment should be considered in RA patients with a disease activity score 28 (DAS 28) superior to 3.2 despite treatment with 20mg/week of methotrexate (MTX) for at least 3 months or, if such treatment is not possible, after 6 months of other conventional disease modifying drug or combination therapy. A DAS 28 score between 2.6 and 3.2 with a significant functional or radiological deterioration under treatment with conventional regimens could also constitute an indication for biological treatment. The treatment goal should be remission or, if that is not achievable, at least a low disease activity, characterized by a DAS28 lower than 3.2, without significative functional or radiological worsening. The response criteria, at the end of the first 3 months of treatment, are a decrease of 0.6 in the DAS28 score. After 6 months of treatment response criteria is defined as a decrease of more than 1.2 in the DAS28 score. Non-responders, in accordance to the Rheumatologist's clinical opinion, should try a switch to another biological agent (tumour necrosis factor antagonist, abatacept, rituximab or tocilizumab).

  5. Structural, spectroscopic and biological investigation of copper oxides nanoparticles with various capping agents

    Energy Technology Data Exchange (ETDEWEB)

    Nowak, A., E-mail: ana.maria.nowak@gmail.com [A. Chelkowski Institute of Physics, University of Silesia, Katowice (Poland); Szade, J.; Talik, E.; Ratuszna, A. [A. Chelkowski Institute of Physics, University of Silesia, Katowice (Poland); Ostafin, M. [Agricultural University of Cracow, Department of Microbiology, Krakow (Poland); Peszke, J. [A. Chelkowski Institute of Physics, University of Silesia, Katowice (Poland)

    2014-06-01

    Powder composed of copper oxides nanoparticles with various capping agents has been synthesized and characterized with the use of X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and X-ray diffraction (XRD). Polyvinyl alcohol (PVA), glycol propylene, glycerin and glycerin plus ammonia were used as capping agents. The scanning electron microscopy (SEM) studies showed that nanoparticles form agglomerates with the size from 80 to 120 nm while particles size determined from the XRD experiment was in the range from 7 to 21 nm. XPS and XRD experiments revealed that depending on capping and reducing agents used in the synthesis nanoparticles are composed of Cu{sub 2}O, CuO or a mixture of them. The biological activity test performed for a selected sample where the capping agent was glycerin plus ammonia has shown promising killing/inhibiting behavior, very effective especially for Gram negatives bacteria. - Highlights: • We obtained copper oxide nanoparticles in a powder form. • Several capping agents were tested. • Structural and chemical tests showed that the main component were Cu{sub 2}O and CuO. • The size of nanoparticles was in the range 7–21 nm. • Nanoparticles with glycerin and ammonia capping agent showed good antibacterial properties.

  6. Cooperative control of multi-agent systems a consensus region approach

    CERN Document Server

    Li, Zhongkui

    2014-01-01

    Distributed controller design is generally a challenging task, especially for multi-agent systems with complex dynamics, due to the interconnected effect of the agent dynamics, the interaction graph among agents, and the cooperative control laws. Cooperative Control of Multi-Agent Systems: A Consensus Region Approach offers a systematic framework for designing distributed controllers for multi-agent systems with general linear agent dynamics, linear agent dynamics with uncertainties, and Lipschitz nonlinear agent dynamics.Beginning with an introduction to cooperative control and graph theory,

  7. A revised timeline for biological agents: revisiting the early years of the germ theory of disease.

    Science.gov (United States)

    Rutecki, Gregory W

    2007-01-01

    An agreed upon timeline for the initial, scientifically-informed use of biological agents typically begins with the Japanese Army in Manchuria and China prior to the generalized outbreak of World War II (1932 until 1945). The process included human experimentation with multiple biological agents followed by their release in combat (e.g. the plague bacillus) targeting military personnel and civilians. Two postulates are used support these dates. First, allegations of earlier bacteriological weapon experimentation and/or use represented the accidental, small scale, and sporadic dispersion of infectious agents preceding the Germ Theory of Disease. Therefore, attempts prior to the Twentieth Century were uninformed scientifically and are not considered representative. Later, as the Germ Theory was maturing, the hypothetical timeline was derived, in part retrospectively, from reputable historical sources (the Trillat Report and The League of Nations) published immediately upon the conclusion of World War I. These documents explicitly testified to the total absence of bacteriological weapons in any form (experimentation or battlefield application) directed at human subjects-in stark contrast to the utilization of chemical agents-during the course of that war. Therefore the Japanese Army in Manchuria became time zero. Recently, evidence previously hidden from outside study has surfaced demonstrating that a small group of Turkish physicians injected typhus-contaminated serum into Armenian civilians during WWI. Although controversy persists regarding primary intent-immunization, experimentation on human subjects, or the introduction of a crude biological weapon-the discovery might suggest a revision to the accepted timeline. The primitive efforts with contaminated serum that occurred during the First World War may seem trivial, especially when compared to overall fatalities during that conflict, but they did include the informed and fatal application of microbial agents

  8. Tracking control for first-order multi-agent systems

    Institute of Scientific and Technical Information of China (English)

    Yang LIU; Yingmin JIA

    2008-01-01

    In this paper,the conventional tracking control problem is expanded to first-order multi-agent systerns,which can be solved by directly guiding any agent in the group.The following three kinds of desired motions are considered for all agents to track:1)stillness in space,2)variable motion with known acceleration,3) variable motion with partly unknown acceleration.Specifically,fixed networks with time delays and switching networks without delays are both considered in case 1).Switching networks with and without time delays are both studied in case 2),while for 3),switching networks without delays are mainly investigated.A numerical simulation example is included to illustrate the results.

  9. TARDY IDEAS ON THE USE OF BIOLOGICAL AGENTS IN RHEUMATIC DISEASES

    OpenAIRE

    Yu. V. Muravyev; L. A. Muravyeva

    2016-01-01

    The past two decades have been marked by the design of a great variety of innovative biological agents, the clinical introduction of which could substantially improve the results of treatment for rheumatic diseases. At the same time, there are a larger number of reports on their administration-associated adverse events, often paradoxical ones (these drugs indicated in many autoimmune processes may induce similar autoimmune processes).

  10. Plasmodium Genus Assay Transition to the Joint Biological Agent Identification and Diagnostic System (JBAIDS)

    Science.gov (United States)

    2012-07-12

    AFRIMS), Bangkok, Thailand Final Report AFMSA O&M FY09 Project (FWH20090036H): Plasmodium Genus Assay Transition to the Joint Biological Agent...evaluation data to support AFPMB approval of the RAPID- based Plasmodium genus assay for use in vector/vector-borne disease surveillance on the RAPID...Objective 1 Results: Plasmodium genus RAPID/JBAIDS assay development activities conducted during the FY09 study did not resolve cross-reactivity

  11. Dermoscopic hemorrhagic dots: an early predictor of response of psoriasis to biologic agents

    Science.gov (United States)

    Lallas, Aimilios; Argenziano, Giuseppe; Zalaudek, Iris; Apalla, Zoe; Ardigo, Marco; Chellini, Patricia; Cordeiro, Natalia; Guimaraes, Mariana; Kyrgidis, Athanassios; Lazaridou, Elizabeth; Longo, Caterina; Moscarella, Elvira; Papadimitriou, Ilias; Pellacani, Giovanni; Sotiriou, Elena; Vakirlis, Efstratios; Ioannides, Dimitrios

    2016-01-01

    Background Biologic agents are routinely used in the treatment of severe psoriasis. The evaluation of treatment response is mainly based on the physician’s global clinical assessment. Objective To investigate whether dermoscopy might enhance the assessment of response of psoriasis to treatment with biologic agents. Methods Patients with severe psoriasis scheduled to receive a biologic agent were enrolled in the study. A target lesion from each patient was clinically and dermoscopically documented at baseline and after one, two and six months. The clinical response was evaluated by the recruiting clinicians at all visits, while dermoscopic images were evaluated by two independent investigators, blinded to the clinical information. Chi Square test was used for cross-tabulation comparisons, while odds ratios, 95% confidence intervals and p values were calculated using univariate logistic regression. Results Overall, there was a significant correlation between clinical response and vessel distribution at all time points: a regular vessel distribution correlated with no response, a clustered distribution with partial response, and the dermoscopic absence of vessels with complete response. The presence of dermoscopic hemorrhagic dots was a potent predictor of favorable clinical response at the subsequent visit at all time points. Among lesions initially clinically responding and later recurring, 87.5% displayed dermoscopic dotted vessels despite the macroscopic remission. Conclusion Dermoscopy might be a useful additional tool for evaluating the response of psoriatic patients to biologic agents. Hemorrhagic dots represent an early predictor of clinical response, while the persistence or reappearance of dotted vessels might predict clinical persistence or recurrence, respectively. PMID:27867739

  12. Molecular modeling toward selective inhibitors of dihydrofolate reductase from the biological warfare agent Bacillus anthracis.

    Science.gov (United States)

    Giacoppo, Juliana O S; Mancini, Daiana T; Guimarães, Ana P; Gonçalves, Arlan S; da Cunha, Elaine F F; França, Tanos C C; Ramalho, Teodorico C

    2015-02-16

    In the present work, we applied docking and molecular dynamics techniques to study 11 compounds inside the enzymes dihydrofolate reductase (DHFR) from the biological warfare agent Bacillus anthracis (BaDHFR) and Homo sapiens sapiens (HssDHFR). Six of these compounds were selected for a study with the mutant BaF96IDHFR. Our results corroborated with experimental data and allowed the proposition of a new molecule with potential activity and better selectivity for BaDHFR.

  13. Control of group of mobile autonomous agents via local strategies

    Institute of Scientific and Technical Information of China (English)

    Lixin GAO; Daizhan CHENG; Yiguang HONG

    2008-01-01

    This paper considers the formation control problem of multi-agent systems in a distributed fashion.Two cases of the information propagating topologies among multiple agents,characterized by graphics model,are considered.One is fixed topology.The other is switching topology which represents the limited and less reliable information exchange.The local formation control strategies established in this paper are based on a simple modification of the existing consensus control strategies.Moreover,some existing convergence conditions ale shown to be a special case of our model even in the continuous-time consensus case.Therefore.the results of this paper extend the existing results about the consensus problem.

  14. The significance of ecology in the development of Verticillium chlamydosporium as a biological agent against root-knot nematodes (Meloidogyne spp.).

    NARCIS (Netherlands)

    Leij, de F.A.A.M.

    1992-01-01

    A thorough understanding of the interactions which occur between nematode parasites and nematode pests and the influence of biotic and abiotic factors on these interactions, is essential in the development of biological control agents for nematodes. The aim of this study was to develop a particular

  15. Chromatographic immunoassays: strategies and recent developments in the analysis of drugs and biological agents.

    Science.gov (United States)

    Matsuda, Ryan; Rodriguez, Elliott; Suresh, Doddavenkatanna; Hage, David S

    2015-01-01

    A chromatographic immunoassay is a technique in which an antibody or antibody-related agent is used as part of a chromatographic system for the isolation or measurement of a specific target. Various binding agents, detection methods, supports and assay formats have been developed for this group of methods, and applications have been reported that range from drugs, hormones and herbicides to peptides, proteins and bacteria. This review discusses the general principles and applications of chromatographic immunoassays, with an emphasis being given to methods and formats that have been developed for the analysis of drugs and biological agents. The relative advantages or limitations of each format are discussed. Recent developments and research in this field, as well as possible future directions, are also considered.

  16. Differential orientation effect in the neural response to interacting biological motion of two agents

    Directory of Open Access Journals (Sweden)

    Kakigi Ryusuke

    2009-04-01

    Full Text Available Abstract Background A recent behavioral study demonstrated that the meaningful interaction of two agents enhances the detection sensitivity of biological motion (BM, however, it remains unclear when and how the 'interaction' information of two agents is represented in our neural system. To clarify this point, we used magnetoencephalography and introduced a novel experimental technique to extract a neuromagnetic response relating to two-agent BM perception. We then investigated how this response was modulated by the interaction of two agents. In the present experiment, we presented two kinds of visual stimuli (interacting and non-interacting BM with two orientations (upright and inverted. Results We found a neuromagnetic response in the bilateral occipitotemporal region, on average 300 – 400 ms after the onset of a two-agent BM stimulus. This result showed that interhemispheric differences were apparent for the peak amplitudes. For the left hemisphere, the orientation effect was manifest when the two agents were made to interact, and the interaction effect was manifest when the stimulus was inverted. In the right hemisphere, the main effects of both orientation and interaction were significant, suggesting that the peak amplitude was attenuated when the visual stimulus was inverted or made to interact. Conclusion These results demonstrate that the 'interaction' information of two agents can affect the neural activities in the bilateral occipitotemporal region, on average 300 – 400 ms after the onset of a two-agent BM stimulus, however, the modulation was different between hemispheres: the left hemisphere is more concerned with dynamics, whereas the right hemisphere is more concerned with form information.

  17. Product Distribution Theory for Control of Multi-Agent Systems

    Science.gov (United States)

    Lee, Chia Fan; Wolpert, David H.

    2004-01-01

    Product Distribution (PD) theory is a new framework for controlling Multi-Agent Systems (MAS's). First we review one motivation of PD theory, as the information-theoretic extension of conventional full-rationality game theory to the case of bounded rational agents. In this extension the equilibrium of the game is the optimizer of a Lagrangian of the (probability distribution of) the joint stare of the agents. Accordingly we can consider a team game in which the shared utility is a performance measure of the behavior of the MAS. For such a scenario the game is at equilibrium - the Lagrangian is optimized - when the joint distribution of the agents optimizes the system's expected performance. One common way to find that equilibrium is to have each agent run a reinforcement learning algorithm. Here we investigate the alternative of exploiting PD theory to run gradient descent on the Lagrangian. We present computer experiments validating some of the predictions of PD theory for how best to do that gradient descent. We also demonstrate how PD theory can improve performance even when we are not allowed to rerun the MAS from different initial conditions, a requirement implicit in some previous work.

  18. Multi-agent cooperation for particle accelerator control

    CERN Document Server

    Skarek, Paul

    1996-01-01

    We present practical investigations in a real industrial controls environment for justifying theoretical DAI (Distributed Artificial Intelligence) results, and we discuss theoretical aspects of practical investigations for accelerator control and operation. A generalized hypothesis is introduced based on a unified view of control, monitoring, diagnosis, maintenance and repair tasks leading to a general method of cooperation for expert systems by exchanging hypotheses. This has been tested for task and result sharing cooperation scenarios. Generalized hypotheses also allow us to treat the repetitive diagnosis-recovery cycle as task sharing cooperation. Problems with such a loop or even recursive calls between the different agents are discussed.

  19. Programmable temperature control system for biological materials

    Science.gov (United States)

    Anselmo, V. J.; Harrison, R. G.; Rinfret, A. P.

    1982-01-01

    A system was constructed which allows programmable temperature-time control for a 5 cu cm sample volume of arbitrary biological material. The system also measures the parameters necessary for the determination of the sample volume specific heat and thermal conductivity as a function of temperature, and provides a detailed measurement of the temperature during phase change and a means of calculating the heat of the phase change. Steady-state and dynamic temperature control is obtained by supplying heat to the sample volume through resistive elements constructed as an integral part of the sample container. For cooling purposes, this container is totally immersed into a cold heat sink. Using a mixture of dry ice and alcohol at 79 C, the sample volume can be controlled from +40 to -60 C at rates from steady state to + or - 65 C/min. Steady-state temperature precision is better than 0.2 C, while the dynamic capability depends on the temperature rate of change as well as the mass of both the sample and the container.

  20. Rotating Biological Contactors (RBC's). Student Manual. Biological Treatment Process Control.

    Science.gov (United States)

    Zickefoose, Charles S.

    This student manual provides the textual material for a unit on rotating biological contactors (RBC's). Topic areas considered include: (1) flow patterns of water through RBC installations; (2) basic concepts (shaft and stage); (3) characteristics of biomass; (4) mechanical features (bearings, mechanical drive systems, and air drive systems); (5)…

  1. Resilient distributed control in the presence of misbehaving agents in networked control systems.

    Science.gov (United States)

    Zeng, Wente; Chow, Mo-Yuen

    2014-11-01

    In this paper, we study the problem of reaching a consensus among all the agents in the networked control systems (NCS) in the presence of misbehaving agents. A reputation-based resilient distributed control algorithm is first proposed for the leader-follower consensus network. The proposed algorithm embeds a resilience mechanism that includes four phases (detection, mitigation, identification, and update), into the control process in a distributed manner. At each phase, every agent only uses local and one-hop neighbors' information to identify and isolate the misbehaving agents, and even compensate their effect on the system. We then extend the proposed algorithm to the leaderless consensus network by introducing and adding two recovery schemes (rollback and excitation recovery) into the current framework to guarantee the accurate convergence of the well-behaving agents in NCS. The effectiveness of the proposed method is demonstrated through case studies in multirobot formation control and wireless sensor networks.

  2. Allee effects in tritrophic food chains: some insights in pest biological control.

    Science.gov (United States)

    Costa, Michel Iskin da S; Dos Anjos, Lucas

    2016-12-01

    Release of natural enemies to control pest populations is a common strategy in biological control. However, its effectiveness is supposed to be impaired, among other factors, by Allee effects in the biological control agent and by the fact that introduced pest natural enemies interact with some native species of the ecosystem. In this work, we devise a tritrophic food chain model where the assumptions previously raised are proved correct when a hyperpredator attacks the introduced pest natural enemy by a functional response type 2 or 3. Moreover, success of pest control is shown to be related to the release of large amounts (i.e., inundative releases) of natural enemies.

  3. System-Awareness for Agent-based Power System Control

    DEFF Research Database (Denmark)

    Heussen, Kai; Saleem, Arshad; Lind, Morten

    2010-01-01

    Operational intelligence in electric power systems is focused in a small number of control rooms that coordinate their actions. A clear division of responsibility and a command hierarchy organize system operation. With multi-agent based control systems, this control paradigm may be shifted...... to a more decentralized openaccess collaboration control paradigm. This shift cannot happen at once, but must fit also with current operation principles. In order to establish a scalable and transparent system control architecture, organizing principles have to be identified that allow for a smooth...... transition. This paper presents a concept for the representation and organization of control- and resource-allocation, enabling computational reasoning and system awareness. The principles are discussed with respect to a recently proposed Subgrid operation concept....

  4. Agent-based distributed hierarchical control of dc microgrid systems

    DEFF Research Database (Denmark)

    Meng, Lexuan; Vasquez, Juan Carlos; Guerrero, Josep M.

    2014-01-01

    In order to enable distributed control and management for microgrids, this paper explores the application of information consensus and local decisionmaking methods formulating an agent based distributed hierarchical control system. A droop controlled paralleled DC/DC converter system is taken...... as a case study. The objective is to enhance the system efficiency by finding the optimal sharing ratio of load current. Virtual resistances in local control systems are taken as decision variables. Consensus algorithms are applied for global information discovery and local control systems coordination....... Standard genetic algorithm is applied in each local control system in order to search for a global optimum. Hardware-in-Loop simulation results are shown to demonstrate the effectiveness of the method....

  5. A review of the use of biological agents for chronic inflammatory demyelinating polyradiculoneuropathy.

    Science.gov (United States)

    Stübgen, Joerg-Patrick

    2013-03-15

    Chronic inflammatory demyelinating polyneuropathy (CIDP) is a group of idiopathic, acquired, immune-mediated inflammatory demyelinating diseases of the peripheral nervous system. A majority of patients with CIDP respond to "first-line" treatment with IVIG, plasmapheresis and/or corticosteroids. There exists insufficient evidence to ascertain the benefit of treatment with "conventional" immunosuppressive drugs. The inconsistent efficacy, long-term financial burden and health risks of non-specific immune altering therapy have drawn recurrent attention to the possible usefulness of a variety of biological agents that target key aspects in the CIDP immunopathogenic pathways. This review aims to give an updated account of the scientific rationale and potential use of biological therapeutics in patients with CIDP. No specific treatment recommendations are given. The discovery, development and application of biological markers by modern molecular diagnostic techniques may help identify drug-naïve or treatment-resistant CIDP patients most likely to respond to targeted immunotherapy.

  6. Population pharmacokinetic-pharmacodynamic modeling of biological agents: when modeling meets reality.

    Science.gov (United States)

    Mould, Diane R; Frame, Bill

    2010-09-01

    The pharmacokinetics (PK) and pharmacodynamics (PD) of many biological agents (biologics) have inherent complexities requiring specialized approaches to develop reliable, unbiased models. Three cases are covered: preponderance of zero values, nonresponder subpopulations, and adaptive dosing. Engineered biologics exhibit high affinity for target receptors. Biologics can saturate receptors, abolishing free receptor levels for protracted periods. Consequently, the distribution of observations can be heavy at, and near, the boundary. A 2-part model (ie, a truncated δ log-normal distribution) may be appropriate. Mixture models identify subpopulations based on bimodal or multimodal distributions of η values. With biologics, PD may be compromised because of lack of receptors, or the PD may be affected because of other events resulting in erratic excursions. Nonresponders exhibit a random walk-around placebo trajectory, resulting in high residual variability. The distributions of etas are often badly skewed or polymodal. An indescribable mixture model separates subjects who are nonresponders, providing diagnostic pharmacologic information on the drug. Many biologics use PD-based adaptive dosing. During model development, data used for model development include adaptive dosing. For simulation, adaptive dosing must be implemented. Failure to account for dose adjustments results in biased or inflated prediction intervals because subjects in the simulated data undergo inappropriate dose adjustments.

  7. Biological control of tropical soda apple (Solanaceae) in Florida: Post-release evaluation

    Science.gov (United States)

    The leaf feeding beetle Gratiana boliviana Spaeth (Coleoptera: Chrysomelidae) was released as a biological control agent against tropical soda apple (TSA) (Solanum viarum Dunal (Solanaceae)) in Sumter County, FL in 2006. Evaluation of beetle feeding damage to TSA plants and changes in the beetle po...

  8. Preliminary study on three pathogens with potential biological control in Barnyard grass (Echinochloa crus galli)

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    @@ More than 10 species of pathogenic fungi were isolated from the naturally infected leaves of barnyard grass (Echinochloa crus-galli) in paddy. After preliminary bioassaying, it was found that the Alternaria alternata (Fr.) keissler(AA), Exserohilum monoceras (EM),and "99-10" were three potential agents for biological control of barnyard grass.

  9. Evolutionary interactions between the invasive tallow tree and herbivores: implications for biological control

    Science.gov (United States)

    Understanding interactions between insect agents and host plants is critical for forecasting their impact before the insects are introduced, and for improving our knowledge of the mechanisms driving success or failure in biological weed control. As invasive plants may undergo rapid adaptive evolutio...

  10. Status of biological control projects on terrestrial invasive alien weeds in California

    Science.gov (United States)

    In cooperation with foreign scientists, we are currently developing new classical biological control agents for five species of invasive alien terrestrial weeds. Cape-Ivy. A gall-forming fly, Parafreutreta regalis, and a stem-boring moth, Digitivalva delaireae, have been favorably reviewed by TAG...

  11. Advanced Algorithms for Rapidly Reconstructing Clandestine Releases of Biological Agents in Urban Areas

    Energy Technology Data Exchange (ETDEWEB)

    Shinn, J.H.; Hall, C.H.; Neher, L.A.; Wilder, F.J.; Gouveia, D.W.; Layton, D.W.; Daniels, J.I.

    2000-02-25

    As the United States plays a greater role in the 21st Century as global peacekeeper and international defender of human rights and democratic principles, there is an increasing likelihood that it will become the focus of acts of terrorism. Such acts of terrorism--sometimes described as ''asymmetric''--could involve the threat or use of weapons of mass destruction (WMD), particularly those considered unconventional, which include ones designed to release chemical or biological agents. In fact, biological agents are of great concern because, as noted by D.A. Henderson of the Center for Civilian Biodefense Studies at Johns Hopkins University in Baltimore, MD, ''... with shortages of hospital space, vaccines, antibiotics, there would be chaos.'' (Williams, 2000). Unfortunately, potential aggressor nations, terrorist groups, and even individuals, can, for a modest cost and effort, develop covert capabilities for manufacturing, transporting, and offensively using biological weapons of mass destruction. Furthermore, there is evidence to indicate that terrorist increasingly are targeting civilian populations--in order to inflict indiscriminate casualties--as well as other more traditional targets such as symbolic buildings or organizations (see Tucker, 1999), which suggest that introducing rapid treatment after a biological event may be more practical than concentrating on prevention (see Siegrist, 1999), especially because sensors are unlikely to be placed in all major urban areas to detect even an atmospheric biological release. For these reasons, and because symptoms for the majority of those effected may not occur or be directly identified for several days, early identification of a covert undetected biological event (CUBE) will contribute to timely medical intervention, which can save many lives.

  12. Halloysite clay nanotubes for controlled release of protective agents.

    Science.gov (United States)

    Lvov, Yuri M; Shchukin, Dmitry G; Möhwald, Helmuth; Price, Ronald R

    2008-05-01

    Halloysite aluminosilicate nanotubes with a 15 nm lumen, 50 nm external diameter, and length of 800 +/- 300 nm have been developed as an entrapment system for loading, storage, and controlled release of anticorrosion agents and biocides. Fundamental research to enable the control of release rates from hours to months is being undertaken. By variation of internal fluidic properties, the formation of nanoshells over the nanotubes and by creation of smart caps at the tube ends it is possible to develop further means of controlling the rate of release. Anticorrosive halloysite coatings are in development and a self-healing approach has been developed for repair mechanisms through response activation to external impacts. In this Perspective, applications of halloysite as nanometer-scale containers are discussed, including the use of halloysite tubes as drug releasing agents, as biomimetic reaction vessels, and as additives in biocide and protective coatings. Halloysite nanotubes are available in thousands of tons, and remain sophisticated and novel natural nanomaterials which can be used for the loading of agents for metal and plastic anticorrosion and biocide protection.

  13. Optimal control in microgrid using multi-agent reinforcement learning.

    Science.gov (United States)

    Li, Fu-Dong; Wu, Min; He, Yong; Chen, Xin

    2012-11-01

    This paper presents an improved reinforcement learning method to minimize electricity costs on the premise of satisfying the power balance and generation limit of units in a microgrid with grid-connected mode. Firstly, the microgrid control requirements are analyzed and the objective function of optimal control for microgrid is proposed. Then, a state variable "Average Electricity Price Trend" which is used to express the most possible transitions of the system is developed so as to reduce the complexity and randomicity of the microgrid, and a multi-agent architecture including agents, state variables, action variables and reward function is formulated. Furthermore, dynamic hierarchical reinforcement learning, based on change rate of key state variable, is established to carry out optimal policy exploration. The analysis shows that the proposed method is beneficial to handle the problem of "curse of dimensionality" and speed up learning in the unknown large-scale world. Finally, the simulation results under JADE (Java Agent Development Framework) demonstrate the validity of the presented method in optimal control for a microgrid with grid-connected mode.

  14. BIOLOGICAL CONTROL OF WEEDS BY MEANS OF PLANT PATHOGENS

    Directory of Open Access Journals (Sweden)

    Marija Ravlić

    2014-06-01

    Full Text Available Biological control is the use of live beneficial organisms and products of their metabolism in the pests control. Plant pathogens can be used for weed control in three different ways: as classical, conservation and augmentative (inoculative and inundated biological control. Inundated biological control involves the use of bioherbicides (mycoherbicides or artificial breeding of pathogens and application in specific stages of crops and weeds. Biological control of weeds can be used where chemical herbicides are not allowed, if resistant weed species are present or in the integrated pest management against weeds with reduced herbicides doses and other non-chemical measures, but it has certain limitations and disadvantages.

  15. Control Architecture for Robotic Agent Command and Sensing

    Science.gov (United States)

    Huntsberger, Terrance; Aghazarian, Hrand; Estlin, Tara; Gaines, Daniel

    2008-01-01

    Control Architecture for Robotic Agent Command and Sensing (CARACaS) is a recent product of a continuing effort to develop architectures for controlling either a single autonomous robotic vehicle or multiple cooperating but otherwise autonomous robotic vehicles. CARACaS is potentially applicable to diverse robotic systems that could include aircraft, spacecraft, ground vehicles, surface water vessels, and/or underwater vessels. CARACaS incudes an integral combination of three coupled agents: a dynamic planning engine, a behavior engine, and a perception engine. The perception and dynamic planning en - gines are also coupled with a memory in the form of a world model. CARACaS is intended to satisfy the need for two major capabilities essential for proper functioning of an autonomous robotic system: a capability for deterministic reaction to unanticipated occurrences and a capability for re-planning in the face of changing goals, conditions, or resources. The behavior engine incorporates the multi-agent control architecture, called CAMPOUT, described in An Architecture for Controlling Multiple Robots (NPO-30345), NASA Tech Briefs, Vol. 28, No. 11 (November 2004), page 65. CAMPOUT is used to develop behavior-composition and -coordination mechanisms. Real-time process algebra operators are used to compose a behavior network for any given mission scenario. These operators afford a capability for producing a formally correct kernel of behaviors that guarantee predictable performance. By use of a method based on multi-objective decision theory (MODT), recommendations from multiple behaviors are combined to form a set of control actions that represents their consensus. In this approach, all behaviors contribute simultaneously to the control of the robotic system in a cooperative rather than a competitive manner. This approach guarantees a solution that is good enough with respect to resolution of complex, possibly conflicting goals within the constraints of the mission to

  16. Adaptive, Distributed Control of Constrained Multi-Agent Systems

    Science.gov (United States)

    Bieniawski, Stefan; Wolpert, David H.

    2004-01-01

    Product Distribution (PO) theory was recently developed as a broad framework for analyzing and optimizing distributed systems. Here we demonstrate its use for adaptive distributed control of Multi-Agent Systems (MASS), i.e., for distributed stochastic optimization using MAS s. First we review one motivation of PD theory, as the information-theoretic extension of conventional full-rationality game theory to the case of bounded rational agents. In this extension the equilibrium of the game is the optimizer of a Lagrangian of the (Probability dist&&on on the joint state of the agents. When the game in question is a team game with constraints, that equilibrium optimizes the expected value of the team game utility, subject to those constraints. One common way to find that equilibrium is to have each agent run a Reinforcement Learning (E) algorithm. PD theory reveals this to be a particular type of search algorithm for minimizing the Lagrangian. Typically that algorithm i s quite inefficient. A more principled alternative is to use a variant of Newton's method to minimize the Lagrangian. Here we compare this alternative to RL-based search in three sets of computer experiments. These are the N Queen s problem and bin-packing problem from the optimization literature, and the Bar problem from the distributed RL literature. Our results confirm that the PD-theory-based approach outperforms the RL-based scheme in all three domains.

  17. Metadata Control Agent approach for Replication in Grid Environments

    Directory of Open Access Journals (Sweden)

    P. SunilGavaskar

    2013-10-01

    Full Text Available since grid environment is dynamic, network latency and user requests may change. In order to provide better communication, access time and fault tolerant in decentralized systems, the replication is a technique to reduce access time, storage space. The objective of the work is to propose an agent control approach for Heterogeneous environments using the Agents for storing objects as replicas in decentralized environments. Our idea minimizes the more replicas (i.e. causes overhead on response time and update cost, therefore maintaining suitable number of replicas is important. Fixed replicas provides file access structure to identify the esteem files and gives optimal replication location, which minimize replication issues like access time and update cost by assuming a given traffic pattern. In this context we present the Agents as replicas to maintain a suitable scalable architecture. The solution uses fewer replicas, which lead to fewer agents as a result of that frequent updating is possible. Our tests show that the proposed strategy outperforms previous solutions in terms of replication issues.

  18. Late effects from whole body irradiation and protection by chemical and biological agents. A review

    Energy Technology Data Exchange (ETDEWEB)

    Maisin, J.R. [Catholic Univ. of Louvain, Brussels (Belgium); Gerber, G.B.

    2000-07-01

    This review described studies attempting to reduce damage of exposure to ionizing radiation with an application of chemical or biological agents by illustrating authors' data to point out which possibilities such protectors might hold in future. Authors described their studies on mice exposed to a single or fractionated dose of X-rays at the Belgian Atomic Center at Mol. Mice were irradiated with 250 kV of X-rays at a dose rate of 1 Gy/min or underwent the fractionated irradiation of 1-week intervals with total dose of 2-25 Gy. Before irradiation, some animals were given glutathione, mercaptoethylamine, cystein, serotonine-creatine, 2{beta}-aminoethylisothiuronium, and other agents, alone or as a mixture. Results indicated that radioprotectors reduced many specific late diseases to different degrees together with protection against tumor induction which other investigators had shown. Future prospects were considered for ideal radioprotectors and searches for new radioprotectors and for combination of biological agents (e.g., cytokines with polysaccharides or prostaglandins) were described. (K.H.)

  19. Assessment of disinfectants in explosive destruction system for biological agent destruction : LDRD final report FY04.

    Energy Technology Data Exchange (ETDEWEB)

    Simmons, Blake Alexander; Didlake, John E. Jr.; Bradshaw, Robert W.; Crooker, Paul J.; Buffleben, George M.

    2005-01-01

    Treatment systems that can neutralize biological agents are needed to mitigate risks from novel and legacy biohazards. Tests with Bacillus thuringiensis and Bacillus steurothemophilus spores were performed in a 190-liter, 1-112 lb TNT equivalent rated Explosive Destruction System (EDS) system to evaluate its capability to treat and destroy biological agents. Five tests were conducted using three different agents to kill the spores. The EDS was operated in steam autoclave, gas fumigation and liquid decontamination modes. The first three tests used EDS as an autoclave, which uses pressurized steam to kill the spores. Autoclaving was performed at 130-140 deg C for up to 2-hours. Tests with chlorine dioxide at 750 ppm concentration for 1 hour and 10% (vol) aqueous chlorine bleach solution for 1 hour were also performed. All tests resulted in complete neutralization of the bacterial spores based on no bacterial growth in post-treatment incubations. Explosively opening a glass container to expose the bacterial spores for treatment with steam was demonstrated and could easily be done for chlorine dioxide gas or liquid bleach.

  20. Control of Dermatomycoses by Physical, Chemical and Biological Agents.

    Science.gov (United States)

    1978-10-31

    were purchased from Sigma Chemical Co. (St. Louis , Mo.). Lycopene was Isolated from tomato according to the method described by Weedor (22...Bacteriol . To E~e pub1Ished in December 1978. 4. Emyanitoff, R. G. and 1. ~1ashimoto . The effect of temperature ,Incubation atmosphere and medium

  1. Portuguese guidelines for the use of biological agents in rheumatoid arthritis - October 2011 update.

    Science.gov (United States)

    Fonseca, João Eurico; Bernardes, Miguel; Canhão, Helena; Santos, Maria José; Quintal, Alberto; Malcata, Armando; Neto, Adriano; Cordeiro, Ana; Rodrigues, Ana; Mourão, Ana Filipa; Ribeiro, Ana Sofia; Cravo, Ana Rita; Barcelos, Anabela; Cardoso, Anabela; Vilar, António; Braña, Arecili; Faustino, Augusto; Silva, Candida; Duarte, Cátia; Araújo, Domingos; Nour, Dolores; Sousa, Elsa; Simões, Eugénia; Godinho, Fátima; Brandão, Filipe; Ventura, Francisco; Sequeira, Graça; Figueiredo, Guilherme; Cunha, Inês; Matos, J Alves; Branco, Jaime; Ramos, João; Costa, José António; Gomes, José António; Pinto, José; Silva, José Canas; Silva, J A; Patto, José Vaz; Costa, Lúcia; Miranda, Luís Cunha; Inês, Luís; Santos, Luís Maurício; Cruz, Margarida; Salvador, Maria João; Ferreira, Maria Júlia; Rial, Maria; Queiroz, Mário Viana; Bogas, Mónica; Araújo, Paula; Reis, Paulo; Abreu, Pedro; Machado, Pedro; Pinto, Patrícia; André, Rui; Melo, Rui; Garcês, Sandra; Cortes, Sara; Alcino, Sérgio; Ramiro, Sofia; Capela, Susana

    2011-01-01

    The authors present the revised version of the Portuguese Society of Rheumatology (SPR) guidelines for the treatment of Rheumatoid Arthritis (RA) with biological therapies. In these guidelines the criteria for introduction and maintenance of biological agents are discussed as well as the contraindications and procedures in the case of nonresponders. Biological treatment (with a tumour necrosis factor antagonist, abatacept or tocilizumab) should be considered in RA patients with a disease activity score 28 (DAS 28) equal to or greater than 3.2 despite treatment with at least 20mg-weekly-dose of methotrexate (MTX) for at least 3 months or, if such treatment is not possible, after 3 months of other conventional disease modifying drug or combination therapy. A DAS 28 score between 2.6 and 3.2 with a significant functional or radiological deterioration under treatment with conventional regimens could also constitute an indication for biological treatment. The treatment goal should be remission or, if that is not achievable, at least a low disease activity, defined by a DAS28 lower than 3.2, without significative functional or radiological worsening. The response criteria, at the end of the first 3 months of treatment, are a decrease of at least 0.6 in the DAS28 score. After 6 months of treatment res­ponse criteria is defined as a decrease greater than 1.2 in the DAS28 score. Non-responders, in accordance to the Rheumatologist’s clinical opinion, should try a switch to another biological agent (tumour necrosis factor antagonist, abatacept, rituximab or tocilizumab).

  2. Complexity, Analysis and Control of Singular Biological Systems

    CERN Document Server

    Zhang, Qingling; Zhang, Xue

    2012-01-01

    Complexity, Analysis and Control of Singular Biological Systems follows the control of real-world biological systems at both ecological and phyisological levels concentrating on the application of now-extensively-investigated singular system theory. Much effort has recently been dedicated to the modelling and analysis of developing bioeconomic systems and the text establishes singular examples of these, showing how proper control can help to maintain sustainable economic development of biological resources. The book begins from the essentials of singular systems theory and bifurcations before tackling  the use of various forms of control in singular biological systems using examples including predator-prey relationships and viral vaccination and quarantine control. Researchers and graduate students studying the control of complex biological systems are shown how a variety of methods can be brought to bear and practitioners working with the economics of biological systems and their control will also find the ...

  3. Decontamination of biological agents from drinking water infrastructure: a literature review and summary.

    Science.gov (United States)

    Szabo, Jeff; Minamyer, Scott

    2014-11-01

    This report summarizes the current state of knowledge on the persistence of biological agents on drinking water infrastructure (such as pipes) along with information on decontamination should persistence occur. Decontamination options for drinking water infrastructure have been explored for some biological agents, but data gaps remain. Data on bacterial spore persistence on common water infrastructure materials such as iron and cement-mortar lined iron show that spores can be persistent for weeks after contamination. Decontamination data show that common disinfectants such as free chlorine have limited effectiveness. Decontamination results with germinant and alternate disinfectants such as chlorine dioxide are more promising. Persistence and decontamination data were collected on vegetative bacteria, such as coliforms, Legionella and Salmonella. Vegetative bacteria are less persistent than spores and more susceptible to disinfection, but the surfaces and water quality conditions in many studies were only marginally related to drinking water systems. However, results of real-world case studies on accidental contamination of water systems with E. coli and Salmonella contamination show that flushing and chlorination can help return a water system to service. Some viral persistence data were found, but decontamination data were lacking. Future research suggestions focus on expanding the available biological persistence data to other common infrastructure materials. Further exploration of non-traditional drinking water disinfectants is recommended for future studies.

  4. Biological control of Ixodes ricinus larvae and nymphs with Metarhizium anisopliae blastospores.

    Science.gov (United States)

    Wassermann, Marion; Selzer, Philipp; Steidle, Johannes L M; Mackenstedt, Ute

    2016-07-01

    The entomopathogenic fungus Metarhizium anisopliae is used as a biological pest control agent against various arthropod species, including ticks. However, the efficacy depends on tick species, tick stage and fungus strain. We studied the effect of M. anisopliae on engorged larvae and nymphs of Ixodes ricinus, the most abundant tick species in Europe, under laboratory and semi-field conditions. A significant reduction of engorged larvae and nymphs could be shown under laboratory as well as under semi-field conditions. Only 3.5% of the larvae treated in the lab and only 18.5% kept under semi-field conditions were able to develop into nymphs compared to the recovered nymphs of the control groups, which were regarded as 100%. Only 7.1% of nymphs were recovered as adult ticks after fungal treatment under semi-field conditions compared to the control (100%). The efficacy of blastospores of M. anisopliae against engorged larvae and nymphs of I. ricinus under semi-field conditions was demonstrated in this study, showing their high potential as a biological control agent of ticks. Further studies will have to investigate the effect of this agent against other stages of I. ricinus as well as other tick species before its value as a biological control agent against ticks can be fully assessed.

  5. Resilient Control System Execution Agent (ReCoSEA)

    Energy Technology Data Exchange (ETDEWEB)

    Craig G. Rieger; Kris Villez

    2012-08-01

    In an increasingly networked world, critical infrastructure systems suffer from two types of vulnerability. The first is the traditionally recognized problem of monitoring the systems for faults and failures, recognizing and analyzing data, and responding with real understanding to the problems of the system. Increasingly complex systems create the opportunity for single points of failure to cascade when inaccurate assessment of system health increases response time or leads to faulty analysis of the problems involved. A second problem involves vulnerability to cyber intrusion, in which bad actors can mask system deterioration or present false data about system status. A resilient system will protect stability, efficiency, and security. To ensure these three states, the system must react to changing conditions within the system with coordination: no one component of the system can be allowed to react to problems without real consideration of the effects of that action on other components within the system. Systems with multi-agent design typically have three layers of action, a management layer, a coordination layer, and an execution layer. A resilient multi-agent system will emphasize functions of the execution layer, which has the responsibility of initiating actions, monitoring, analyzing, and controlling its own processes, while feeding information back to the higher levels of management and coordination. The design concept of a resilient control system execution agent (ReCoSEA) grows out of these underpinnings, and through the use of computational intelligence techniques, this paper suggests an associated design methodology.

  6. A Novel Agent Based Approach for Controlling Network Storms

    CERN Document Server

    Nair, Dr T R Gopalakrishnan; M, Vaidehi

    2011-01-01

    One of the fundamental data transmission mechanisms in Ethernet LAN is broadcasting. Flooding is a direct broadcasting technique used in these networks. A significant drawback of this method is that it can lead to broadcast storms. This phenomenon is more common in multivendor switch environment. Broadcast storms usually results in dissension, collision and redundancy leading to degradation of the network performance. Most of the storms appear without much warning and it affects the efficiency of network even in situations when the network is expected to work most efficiently. There are several characteristic patterns by which storm can appear in a LAN, like rate monotonic repetition, transient appearances with different types of growth properties and decay profiles. In this paper we discuss the storm build up pattern in an industry and present various reasons for storm in LAN. We have identified a strategy for controlling network storms, using multiple static agents. These agents inhibit storm packet regener...

  7. Design, synthesis, and biological evaluation of anti-EV71 agents.

    Science.gov (United States)

    Li, Peng; Yang, Bailing; Hao, Fei; Wang, Ping; He, Haiying; Huang, Lei; Zhang, Xuan; Zhang, Shengbin; Peng, Xuanjia; Yin, Ke; Hu, Jiao; Chen, Xinsheng; Gu, Zhengxian; Wang, Li; Shen, Liang; Hu, Guoping; Li, Ning; Li, Jian; Chen, Shuhui; Xiao, Wei; Wang, Zhenzhong; Guo, Qingming; Chang, Xiujuan; Zhang, Lanjun; Cai, Qixu; Lin, Tianwei

    2016-07-15

    Enterovirus 71 (EV71) is a major causative agent of hand, foot and mouth disease (HFMD), which can spread its infections to the central nervous and other systems with severe consequences. In this article, design, chemical synthesis, and biological evaluation of various anti-EV71 agents which incorporate Michael acceptors are described. Further SAR study demonstrated that lactone type of Michael acceptor provided a new lead of anti-EV71 drug candidates with high anti-EV71 activity in cell-based assay and enhanced mouse plasma stability. One of the most potent compounds (2K, cell-based anti-EV71 EC50=0.028μM), showed acceptable stability profile towards mouse plasma, which resulted into promising pharmacokinetics in mouse via IP administration.

  8. Maternal feeding controls fetal biological clock.

    Directory of Open Access Journals (Sweden)

    Hidenobu Ohta

    Full Text Available BACKGROUND: It is widely accepted that circadian physiological rhythms of the fetus are affected by oscillators in the maternal brain that are coupled to the environmental light-dark (LD cycle. METHODOLOGY/PRINCIPAL FINDINGS: To study the link between fetal and maternal biological clocks, we investigated the effects of cycles of maternal food availability on the rhythms of Per1 gene expression in the fetal suprachiasmatic nucleus (SCN and liver using a transgenic rat model whose tissues express luciferase in vitro. Although the maternal SCN remained phase-locked to the LD cycle, maternal restricted feeding phase-advanced the fetal SCN and liver by 5 and 7 hours respectively within the 22-day pregnancy. CONCLUSIONS/SIGNIFICANCE: Our results demonstrate that maternal feeding entrains the fetal SCN and liver independently of both the maternal SCN and the LD cycle. This indicates that maternal-feeding signals can be more influential for the fetal SCN and particular organ oscillators than hormonal signals controlled by the maternal SCN, suggesting the importance of a regular maternal feeding schedule for appropriate fetal molecular clockwork during pregnancy.

  9. Optically controlled collisions of biological objects

    Science.gov (United States)

    Davies, Benjamin J.; Kishore, Rani; Mammen, Mathai; Helmerson, Kristian; Choi, Seok-Ki; Phillips, William D.; Whitesides, George M.

    1998-04-01

    We have developed a new assay in which two mesoscale particles are caused to collide using two independently controlled optical tweezers. This assay involves the measurement of the adhesion probability following a collision. Since the relative orientation, impact parameter (i.e., distance of closest approach), and collision velocity of the particles, as well as the components of the solution, are all under the user's control, this assay can mimic a wide range of biologically relevant collisions. We illustrate the utility of our assay by evaluating the adhesion probability of a single erythrocyte (red blood cell) to an influenza virus-coated microsphere, in the presence of sialic acid-bearing inhibitors of adhesion. This probability as a function of inhibitor concentration yields a measure of the effectiveness of the inhibitor for blocking viral adhesion. Most of the inhibition constants obtained using the tweezers agree well with those obtained from other techniques, although the inhibition constants for the best of the inhibitors were beyond the limited resolution of conventional assays. They were readily evaluated using our tweezers-based assay, however, and prove to be the most potent inhibitors of adhesion between influenza virus and erythrocytes ever measured. Further studies are underway to investigate the effect of collision velocity on the adhesion probability, with the eventual goal of understanding the various mechanisms of inhibition (direct competition for viral binding sites versus steric stabilization). Analysis of these data also provide evidence that the density of binding sites may be a crucial parameter in the application of this assay and polymeric inhibition in general.

  10. Determination of gadolinium-based MRI contrast agents in biological and environmental samples: A review

    Energy Technology Data Exchange (ETDEWEB)

    Telgmann, Lena [University of Münster, Institute of Inorganic and Analytical Chemistry, Münster (Germany); Sperling, Michael [University of Münster, Institute of Inorganic and Analytical Chemistry, Münster (Germany); European Virtual Institute for Speciation Analysis (EVISA), Münster (Germany); Karst, Uwe, E-mail: uk@uni-muenster.de [University of Münster, Institute of Inorganic and Analytical Chemistry, Münster (Germany)

    2013-02-18

    Highlights: ► All major methods for the analysis of Gd-based MRI contrast agents are discussed. ► Biological and environmental samples are covered. ► Pharmacokinetics and species transformation can be investigated. ► The figures of merit as limit of detection and analysis time are described. -- Abstract: The development of analytical methods and strategies to determine gadolinium and its complexes in biological and environmental matrices is evaluated in this review. Gadolinium (Gd) chelates are employed as contrast agents for magnetic resonance imaging (MRI) since the 1980s. In general they were considered as safe and well-tolerated, when in 2006, the disease nephrogenic systemic fibrosis (NSF) was connected to the administration of MRI contrast agents based on Gd. Pathogenesis and etiology of NSF are yet unclear and called for the development of several analytical methods to obtain elucidation in this field. Determination of Gd complex stability in vitro and in vivo, as well as the quantification of Gd in body fluids like blood and urine was carried out. Separation of the Gd chelates was achieved with high performance liquid chromatography (HPLC) and capillary electrophoresis (CE). For detection, various methods were employed, including UV–vis absorbance and fluorescence spectroscopy, electrospray ionization mass spectrometry (ESI-MS) and inductively coupled plasma mass spectrometry (ICP-MS). A second challenge for analysts was the discovery of high concentrations of anthropogenic Gd in surface waters draining populated areas. The source could soon be determined to be the increasing administration of Gd complexes during MRI examinations. Identification and quantification of the contrast agents was carried out in various surface and groundwater samples to determine the behavior and fate of the Gd chelates in the environment. The improvement of limits of detection (LOD) and limits of quantification (LOQ) was and still is the goal of past and ongoing

  11. Multi-agent Optimal Control of Ball Balancing on a Mobile

    Directory of Open Access Journals (Sweden)

    Adel Akbarimajd

    2015-12-01

    Full Text Available Multi-agent systems have origin in computer engineering however, they have found applications in different field. One of the newly emerged problems in multi-agent systems is multi-agent control. In multi-agent control it is desired that the control is done in distributed manner. That is the controller of each agent should be implemented based on local feedback. In this a mechanism is introuded as a test bed for multi-agent control systems. The introduced mechanism is balancing of a ball on link located on a planar mobile robot. Dynamic equations of the mechanism is derived and the control task is distributed among two agents. For each agent a two loop controller designed wherein external loop is a LQR controller and inner loop is a simple proportional controller. Regulation and fault tolerance performance of controller scheme is evaluated by simulations.

  12. Predator interference effects on biological control: The "paradox" of the generalist predator revisited

    Science.gov (United States)

    Parshad, Rana D.; Bhowmick, Suman; Quansah, Emmanuel; Basheer, Aladeen; Upadhyay, Ranjit Kumar

    2016-10-01

    An interesting conundrum in biological control questions the efficiency of generalist predators as biological control agents. Theory suggests, generalist predators are poor agents for biological control, primarily due to mutual interference. However field evidence shows they are actually quite effective in regulating pest densities. In this work we provide a plausible answer to this paradox. We analyze a three species model, where a generalist top predator is introduced into an ecosystem as a biological control, to check the population of a middle predator, that in turn is depredating on a prey species. We show that the inclusion of predator interference alone, can cause the solution of the top predator equation to blow-up in finite time, while there is global existence in the no interference case. This result shows that interference could actually cause a population explosion of the top predator, enabling it to control the target species, thus corroborating recent field evidence. Our results might also partially explain the population explosion of certain species, introduced originally for biological control purposes, such as the cane toad (Bufo marinus) in Australia, which now functions as a generalist top predator. We also show both Turing instability and spatio-temporal chaos in the model. Lastly we investigate time delay effects.

  13. Use of mixed cultures of biocontrol agents to control sheep nematodes.

    Science.gov (United States)

    Baloyi, M A; Laing, M D; Yobo, K S

    2012-03-23

    Biological control is a promising non-chemical approach for the control of gastrointestinal nematodes of sheep. Use of combinations of biocontrol agents have been reported to be an effective method to increase the efficacy of biological control effects. In this study, combinations of either two Bacillus thuringiensis (Bt) or Clonostachys rosea (C. rosea) isolates and Bt+C. rosea isolates were evaluated in vitro in microtitre plates for their biocontrol activity on sheep nematodes. The Baermann technique was used to extract the surviving L3 larval stages of intestinal nematodes and counted under a dissecting microscope to determine the larval counts. Results indicate that there was a significant reduction of nematode counts due to combination of biocontrol agents (Pnematodes counts by 72.8%, 64% and 29.8%. The results revealed a control level of 57% when C. rosea isolates P3+P8 were combined. Combination of Bt and C. rosea isolates B10+P8 caused the greatest mortality of 76.7%. Most combinations were antagonistic, with only a few combinations showing an additive effect. None were synergistic. The isolate combinations were more effective than when isolates were used alone.

  14. Autonomous Detection of Aerosolized Biological Agents by Multiplexed Immunoassay with PCR Confirmation

    Energy Technology Data Exchange (ETDEWEB)

    Hindson, B J; McBride, M T; Makarewicz, A J; Henderer, B D; Setlur, U S; Smith, S M; Gutierrez, D M; Metz, T R; Nasarabadi, S L; Venkateswaran, K S; Farrow, S W; Colston, Jr., B W; Dzenitis, J M

    2004-05-27

    The autonomous pathogen detection system (APDS) is an automated, podium-sized instrument that continuously monitors the air for biological threat agents (bacteria, viruses, and toxins). The system has been developed to warn of a biological attack in critical or high-traffic facilities and at special events. The APDS performs continuous aerosol collection, sample preparation, and detection using multiplexed immunoassay followed by confirmatory PCR using real-time TaqMan assays. We have integrated completely reusable flow-through devices that perform DNA extraction and PCR amplification. The fully integrated system was challenged with aerosolized Bacillus anthracis, Yersinia pestis, Bacillus globigii and botulinum toxoid. By coupling highly selective antibody and DNA based assays, the probability of an APDS reporting a false positive is extremely low.

  15. Will the Convention on Biological Diversity put an end to biological control?

    Directory of Open Access Journals (Sweden)

    Joop C. van Lenteren

    2011-03-01

    Full Text Available Will the Convention on Biological Diversity put an end to biological control? Under the Convention on Biological Diversity countries have sovereign rights over their genetic resources. Agreements governing the access to these resources and the sharing of the benefits arising from their use need to be established between involved parties. This also applies to species collected for potential use in biological control. Recent applications of access and benefit sharing principles have already made it difficult or impossible to collect and export natural enemies for biological control research in several countries. If such an approach is widely applied it would impede this very successful and environmentally safe pest management method based on the use of biological diversity. The International Organization for Biological Control of Noxious Animals and Plants has, therefore, created the "Commission on Biological Control and Access and Benefit Sharing". This commission is carrying out national and international activities to make clear how a benefit sharing regime might seriously frustrate the future of biological control. In addition, the IOBC Commission members published information on current regulations and perceptions concerning exploration for natural enemies and drafted some 30 case studies selected to illustrate a variety of points relevant to access and benefit sharing. In this article, we summarize our concern about the effects of access and benefit sharing systems on the future of biological control.

  16. Effect of capping agents: Structural, optical and biological properties of ZnO nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Javed, Rabia [Department of Biotechnology, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad 45320 (Pakistan); Usman, Muhammad, E-mail: uk_phy@yahoo.com [Department of Physics, Faculty of Natural Sciences, Quaid-i-Azam University, Islamabad 45320 (Pakistan); Department of Physics, School of Science and Engineering, Lahore University of Management Sciences, Lahore 54729 (Pakistan); Tabassum, Saira; Zia, Muhammad [Department of Biotechnology, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad 45320 (Pakistan)

    2016-11-15

    Highlights: • ZnO nanoparticles have been effectively capped with polyethylene glycol (PEG) and polyvinyl pyrrolidone (PVP) shown by the data of XRD, FTIR and UV–visible spectroscopy. • Reduction in size occurred from 34 nm to 26 nm due to capping agent and band gap energy increases with the decrease in the particle size. • Antibacterial activity against Gram-positive bacteria is greater than the Gram-negative bacteria. • All biological assays reveal highest activities in capped ZnO nanoparticles as compared to the uncapped ZnO nanoparticles. • Highest antibacterial activity has been exhibited by ZnO-PVP while highest antioxidant and antidiabetic activities have been conferred by ZnO- PEG. - Abstract: Different biological activities of capped and uncapped ZnO nanoparticles were investigated, and the effects of potential capping agents on these biological activities were studied. ZnO nanoparticles were synthesized and capped by polyethylene glycol (PEG) and polyvinyl pyrrolidone (PVP) using a simple chemical method of co-precipitation. Characterization by X-ray diffraction (XRD), Fourier transform Infrared spectroscopy (FTIR) and UV–vis spectroscopy confirmed the crystallinity, size, functional group, and band gap of synthesized nanoparticles. Reduction in size occurred from 34 nm to 26 nm due to surfactant. Results of all biological activities indicated significantly higher values in capped as compared to uncapped nanoparticles. Antibacterial activity against Staphylococcus aureus (ATCC 6538), Bacillus subtilis (ATCC 6633), Escherichia coli (ATCC15224), and Acetobacter was obtained. This activity was more prominent against Gram-positive bacteria, and ZnO-PVP nanoparticles elucidated highest antibacterial activity (zone of inhibition 17 mm) against Gram-positive, Bacillus subtilis species. Antioxidant activities including total flavonoid content, total phenolic content, total antioxidant capacity, total reducing power and %age inhibition of DPPH, and

  17. Iterative learning control for multi-agent systems coordination

    CERN Document Server

    Yang, Shiping; Li, Xuefang; Shen, Dong

    2016-01-01

    A timely guide using iterative learning control (ILC) as a solution for multi-agent systems (MAS) challenges, this book showcases recent advances and industrially relevant applications. Readers are first given a comprehensive overview of the intersection between ILC and MAS, then introduced to a range of topics that include both basic and advanced theoretical discussions, rigorous mathematics, engineering practice, and both linear and nonlinear systems. Through systematic discussion of network theory and intelligent control, the authors explore future research possibilities, develop new tools, and provide numerous applications such as power grids, communication and sensor networks, intelligent transportation systems, and formation control. Readers will gain a roadmap of the latest advances in the fields and can use their newfound knowledge to design their own algorithms.

  18. Morphological Control Agent in Ternary Blend Bulk Heterojunction Solar Cells

    Directory of Open Access Journals (Sweden)

    Hsueh-Chung Liao

    2014-11-01

    Full Text Available Bulk heterojunction (BHJ organic photovoltaic (OPV promise low cost solar energy and have caused an explosive increase in investigations during the last decade. Control over the 3D morphology of BHJ blend films in various length scales is one of the pillars accounting for the significant advance of OPV performance recently. In this contribution, we focus on the strategy of incorporating an additive into BHJ blend films as a morphological control agent, i.e., ternary blend system. This strategy has shown to be effective in tailoring the morphology of BHJ through different inter- and intra-molecular interactions. We systematically review the morphological observations and associated mechanisms with respect to various kinds of additives, i.e., polymers, small molecules and inorganic nanoparticles. We organize the effects of morphological control (compatibilization, stabilization, etc. and provide general guidelines for rational molecular design for additives toward high efficiency and high stability organic solar cells.

  19. A Novel Secondary Control for Microgrid Based on Synergetic Control of Multi-Agent System

    Directory of Open Access Journals (Sweden)

    Zhiwen Yu

    2016-03-01

    Full Text Available In power systems, the secondary control is a very useful way to restore the system frequency and voltage to the rated value. This paper tries to propose a secondary frequency and voltage control of islanded microgrids based on the distributed synergetic control of multi-agent systems. In the proposed control, since each distributed generation only requires its own information and that of the neighbors, the secondary control is fully distributed. The system is more reliable because the central controller and complex communication network are reduced in the distributed structure. Based on multi-agent systems, the dynamic model is established, and distributed synergetic control algorithms are given to design the secondary control of the islanded microgrid. Meanwhile, the system has globally asymptotic stability under the proposed control, which is proved by the direct Lyapunov method. Simulation results about a test microgrid are given to verify the effectiveness of the proposed control.

  20. Optimizing urban traffic control using a rational agent

    Institute of Scientific and Technical Information of China (English)

    Salvador IBARRA-MARTÍNEZ; José A. CASTÁN-ROCHA; Julio LARIA-MENCHACA

    2014-01-01

    This paper is devoted to developing and evaluating a set of technologies with the objective of designing a method-ology for the implementation of sophisticated traffic lights by means of rational agents. These devices would be capable of op-timizing the behavior of a junction with multiple traffic signals, reaching a higher level of autonomy without losing reliability, accuracy, or efficiency in the offered services. In particular, each rational agent in a traffic signal will be able to analyze the requirements and constraints of the road, in order to know its level of demand. With such information, the rational agent will adapt its light cycles with the view of accomplishing more fluid traffic patterns and minimizing the pollutant environmental emissions produced by vehicles while they are stopped at a red light, through using a case-based reasoning (CBR) adaptation. This paper also integrates a microscopic simulator developed to run a set of tests in order to compare the presented methodology with traditional traffic control methods. Two study cases are shown to demonstrate the efficiency of the introduced approach, increasing vehicular mobility and reducing harmful activity for the environment. For instance, in the first scenario, taking into account the studied traffic volumes, our approach increases mobility by 23%and reduces emissions by 35%. When the roads are managed by sophisticated traffic lights, a better level of service and considerable environmental benefits are achieved, demon-strating the utility of the presented approach.

  1. Biological control with Trichogramma pretiosum increases organic maize productivity by 19.4%

    OpenAIRE

    de Lourdes Corrêa Figueiredo, Maria; Cruz, Ivan; da Silva, Rafael Braga; Foster, John Edward

    2015-01-01

    International audience; AbstractSpodoptera frugiperda is a major pest causing maize yield loss in Brazil. There is therefore a need for control methods, notably for organic farming because classical pesticides are not allowed. A potential solution for organic maize is to apply the biological control agent Trichogramma pretiosum to reduce S. frugiperda populations. Here, we tested the application of one, two, or three releases of T. pretiosum. We measured plant damage ratings, egg masses paras...

  2. The Effects of Biological Agents on Melanocytic Nevi: A Preliminary Report

    Directory of Open Access Journals (Sweden)

    Nurşah Doğan

    2016-03-01

    Full Text Available Objective: The aim of our study was to evaluate the changes of the melanocytic nevi during the biological agent therapy. Methods: For this purpose, 40 index nevi of 25 adult patients who were treated with infliximab, adalimumab, etanercept or rituximab were included in this study. All of the patients underwent clinical and dermoscopic evaluation before the beginning of the treatment, 6 months and 1 year after the beginning of the treatment. Among dermoscopic examination methods, pattern analysis, ABCD score system and three-point checklist were performed. Results: In terms of the diameter of the index nevi, there was no statistically significant difference between the first examination and that of the sixth month, but differences was observed between the first examination and that of the twelfth month. There was also no statistically significant difference in total dermoscopy scores calculated by ABCD score system application on 31 nevi at the times of assessment. At the end of the study, we detected 24 new nevi formation in 7 patients, whom all of were over 35 years of age, however no eruptive nevi or melanoma formation were observed. Conclusion: An increase in the diameters of the present nevi and formation of new nevi may be seen with biological agent therapy in one-year-follow-up.

  3. New treatment strategy including biological agents in patients with systemic lupus erythematosus.

    Science.gov (United States)

    Leszczyński, Piotr; Pawlak-Buś, Katarzyna

    2013-01-01

    Systemic lupus erythematosus (SLE) is a heterogeneous disease, in which B lymphocyte activation and chronic inflammation play the key role. Both the disease itself and its treatment cause damage to multiple organs and systems. So far, despite intensive treatment, disease remission has been achieved in few patients, and the ratio of organ complications has increased significantly. This is caused by a long‑term glucocorticoid therapy with a relatively rare use of immunosuppressive drugs. With a new treatment strategy and modern immunotherapy, it is possible to reduce the mortality rate, limit multiple‑organ damage, thereby significantly improving the quality of life and prognosis of patients with SLE. The "treat‑to‑target" strategy enables targeted treatment resulting in a long‑term symptom remission. It is based on an intensive immunosuppressive treatment with simultaneous reduction of glucocorticoid doses, and limiting their use solely to exacerbations in disease activity. The current idea for treatment is also the conscious use of the beneficial potential of background SLE treatment including antimalarial agents and standard immunosuppressive therapy. With the first biological agent approved for SLE treatment, the new age of therapy has dawned. Biologics offer new prospects and possibilities to induce clinical and immunological remission of SLE.

  4. INFLUENCE OF BIOLOGICALLY ACTIVE AGENTS ON A STRUCTURAL STATE AND THE ENZYMATIC ACTIVITY OF BLACK ORDINARY CARBONATED SOIL

    Directory of Open Access Journals (Sweden)

    Lychman V. A.

    2014-04-01

    Full Text Available The results of a long-term research of the influence of various biologically active agents (a humic preparation Lignogumat and microbiological Baikal EM fertilizer on a structural state and the enzymatic activity of ordinary carbonated black soil are presented. It has been established that biologically active substances contribute to increased enzymatic activity, humus and improve the soil structure

  5. Basic analytical methods for identification of erythropoiesis-stimulating agents in doping control

    Science.gov (United States)

    Postnikov, P. V.; Krotov, G. I.; Efimova, Yu A.; Rodchenkov, G. M.

    2016-02-01

    The design of new erythropoiesis-stimulating agents for clinical use necessitates constant development of methods for detecting the abuse of these substances, which are prohibited under the World Anti-Doping Code and are included in the World Anti-Doping Agency (WADA) prohibited list. This review integrates and describes systematically the published data on the key methods currently used by WADA-accredited anti-doping laboratories around the world to detect the abuse of erythropoiesis-stimulating agents, including direct methods (various polyacrylamide gel electrophoresis techniques, enzyme-linked immunosorbent assay, membrane enzyme immunoassay and mass spectrometry) and indirect methods (athlete biological passport). Particular attention is given to promising approaches and investigations that can be used to control prohibited erythropoietins in the near future. The bibliography includes 122 references.

  6. Homeostasis control of building environment using sensor agent robot

    Science.gov (United States)

    Nagahama, Eri; Mita, Akira

    2012-04-01

    A human centered system for building is demanded to meet variety of needs due to the diversification and maturation of society. Smart buildings and smart houses have been studied to satisfy this demand. However, it is difficult for such systems to respond flexibly to unexpected events and needs that are caused by aging and complicate emotion changes. With this regards, we suggest "Biofied Buildings". The goal for this research is to realize buildings that are safer, more comfortable and more energy-efficient by embedding adaptive functions of life into buildings. In this paper, we propose a new control system for building environments, focused on physiological adaptation, particularly homeostasis, endocrine system and immune system. Residents are used as living sensors and controllers in the control loop. A sensor agent robot is used to acquire resident's discomfort feeling, and to output hormone-like signals to activate devices to control the environments. The proposed system could control many devices without establishing complicated scenarios. Results obtained from some simulations and the demonstration experiments using an LED lighting system showed that the proposed system were able to achieve robust and stable control of environments without complicated scenarios.

  7. Detection of aerosolized biological agents by immunoassay followed by autonomous PCR confirmation

    Energy Technology Data Exchange (ETDEWEB)

    Dzenitis, J M; Hindson, B J; McBride, M T; Makarewicz, A J; Henderer, B D; Sathyam, U S; Smith, S M; Gutierrez, D M; Metz, T R; Venkateswaran, K S; Colston, B W; Farrow, S W

    2003-12-15

    An Autonomous Pathogen Detection System (APDS) unit is an automated, podium-sized system that monitors the air for all three biological threat agents (bacteria, viruses, and toxins). The system has been developed under the auspices of the U. S. Department of Energy and Department of Homeland Security by the University of California, Lawrence Livermore National Laboratory (LLNL) to protect people in critical or high-traffic facilities and at special events. The system performs continuous aerosol collection, sample preparation, and multiplexed biological tests using advanced immunoassays as the primary screen. Over ten agents are assayed at once, and results are reported hourly. R&D work this year focused on incorporating polymerase chain-reaction (PCR) techniques for detecting DNA as confirmation of immunoassay positives. The primary objective of the Dugway testing was to demonstrate the APDS with immunoassay identification and PCR confirmation of bacteria. A secondary objective was to demonstrate immunoassay identification of a protein toxoid (denatured toxin) aerosol release. A total of 12 agent trials were conducted over 14 days of testing, for a total of four work weeks at Dugway. Both testing objectives were achieved with multiple releases and clear identifications. The APDS was shown to be effective for identifying aerosolized Bacillus anthracis, Yersinia pestis, Bacillus globigii, and botulinum toxoid. The two areas for improvement were operational as opposed to hardware-related. The first was slowing the PCR thermal cycling to achieve stronger signals, which was demonstrated during the later phases of testing. The second area is to improve the parameters for autonomous PCR triggering; this is one of the focuses of the upcoming year's work.

  8. Possibility of biological control of primocane fruiting raspberry disease caused by Fusarium sambucinum.

    Science.gov (United States)

    Shternshis, Margarita V; Belyaev, Anatoly A; Matchenko, Nina S; Shpatova, Tatyana V; Lelyak, Anastasya A

    2015-10-01

    Biological control agents are a promising alternative to chemical pesticides for plant disease suppression. The main advantage of the natural biocontrol agents, such as antagonistic bacteria compared with chemicals, includes environmental pollution prevention and a decrease of chemical residues in fruits. This study is aimed to evaluate the impact of three Bacillus strains on disease of primocane fruiting raspberry canes caused by Fusarium sambucinum under controlled infection load and uncontrolled environmental factors. Bacillus subtilis, Bacillus licheniformis, and Bacillus amyloliquefaciens were used for biocontrol of plant disease in 2013 and 2014 which differed by environmental conditions. The test suspensions were 10(5) CFU/ml for each bacterial strain. To estimate the effect of biological agents on Fusarium disease, canes were cut at the end of vegetation, and the area of outer and internal lesions was measured. In addition to antagonistic effect, the strains revealed the ability to induce plant resistance comparable with chitosan-based formulation. Under variable ways of cane treatment by bacterial strains, the more effective were B. subtilis and B. licheniformis demonstrating dual biocontrol effect. However, environmental factors were shown to impact the strain biocontrol ability; changes in air temperature and humidity led to the enhanced activity of B. amyloliquefaciens. For the first time, the possibility of replacing chemicals with environmentally benign biological agents for ecologically safe control of the raspberry primocane fruiting disease was shown.

  9. Step-coordination Algorithm of Traffic Control Based on Multi-agent System

    Institute of Scientific and Technical Information of China (English)

    Hai-Tao Zhang; Fang Yu; Wen Li

    2009-01-01

    Aiming at the deficiency of conventional traffic control method, this paper proposes a new method based on multi-agent technology for traffic control. Different from many existing methods, this paper distinguishes traffic control on the basis of the agent technology from conventional traffic control method. The composition and structure of a multi-agent system (MAS) is first discussed. Then, the step-coordination strategies of intersection-agent, segment-agent, and area-agent are put forward. The advantages of the algorithm are demonstrated by a simulation study.

  10. New Biologic Drug Tackles Hard-To-Control Asthma

    Science.gov (United States)

    ... html New Biologic Drug Tackles Hard-to-Control Asthma Benralizumab significantly cuts respiratory attacks, two trials show ... drug reduces flare-ups in patients with severe asthma that is not controlled by steroid inhalers alone, ...

  11. Dynamical Systems and Control Theory Inspired by Molecular Biology

    Science.gov (United States)

    2014-10-02

    in both bacterial and eukaryotic signaling pathways. A common theme in the systems biology literature is that certain systems whose output variables...AFRL-OSR-VA-TR-2014-0282 DYNAMICAL SYSTEMS AND CONTROL THEORY INSPIRED BY MOLECULAR BIOLOGY Eduardo Sontag RUTGERS THE STATE UNIVERSITY OF NEW JERSEY...Standard Form 298 (Re . 8-98) v Prescribed by ANSI Std. Z39.18 DYNAMICAL SYSTEMS AND CONTROL THEORY INSPIRED BY MOLECULAR BIOLOGY AFOSR FA9550-11-1-0247

  12. Biologic agents for rheumatoid arthritis treatment%类风湿关节炎的生物制剂治疗

    Institute of Scientific and Technical Information of China (English)

    陈龙; 袁国华

    2011-01-01

    Rheumatoid arthritis is a common disabling diease, seriously affecting the patients' quality of life. Traditional drugs treatment for rheumatoid arthritis include nonsteroid anti-inflammatory drugs, corticosteroids, and disease modifying antirheumatic drugs,however,these drugs are often not satisfied to control the condition of refractory rheumatoid arthritis,and resulting in severe joint damage. Recently , the emergence of multiple biological agents brought hope to the treatment of refractory rheumatoid arthritis patients These agents play an important role in the control of rheumatic conditions and the improvement of quality of life in PtA patients.%类风湿关节炎(rheumatoid arthritis,RA)是一种常见的致残性疾病,严重影响患者的生活质量.传统的RA药物治疗主要包括非甾体抗炎药、糖皮质激素以及慢作用药物,然而这些药物常常不能满意控制那些难治性RA患者的病情,最终导致关节进行性破坏.近年,由于多种生物制剂的出现,为治疗难治性RA带来了希望,这些生物制剂在控制风湿病情和改善生活质量方面发挥了重要作用.

  13. The acquisition of dangerous biological materials: Technical facts sheets to assist risk assessments of 46 potential BW agents

    Energy Technology Data Exchange (ETDEWEB)

    Aceto, Donato Gonzalo [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Astuto-Gribble, Lisa M. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Gaudioso, Jennifer M. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2007-11-01

    Numerous terrorist organizations have openly expressed interest in producing and deploying biological weapons. However, a limiting factor for many terrorists has been the acquisition of dangerous biological agents, as evidenced by the very few successful instances of biological weapons use compared to the number of documented hoaxes. Biological agents vary greatly in their ability to cause loss of life and economic damage. Some agents, if released properly, can kill many people and cause an extensive number of secondary infections; other agents will sicken only a small number of people for a short period of time. Consequently, several biological agents can potentially be used to perpetrate a bioterrorism attack but few are likely capable of causing a high consequence event. It is crucial, from a US national security perspective, to more deeply understand the likelihood that terrorist organizations can acquire the range of these agents. Few studies have attempted to comprehensively compile the technical information directly relevant to the acquisition of dangerous bacteria, viruses and toxins. In this report, technical fact sheets were assembled for 46 potentially dangerous biological agents. Much of the information was taken from various research sources which could ultimately and significantly expedite and improve bioterrorism threat assessments. By systematically examining a number of specific agent characteristics included in these fact sheets, it may be possible to detect, target, and implement measures to thwart future terrorist acquisition attempts. In addition, the information in these fact sheets may be used as a tool to help laboratories gain a rudimentary understanding of how attractive a method laboratory theft is relative to other potential acquisition modes.

  14. Effect of capping agents: Structural, optical and biological properties of ZnO nanoparticles

    Science.gov (United States)

    Javed, Rabia; Usman, Muhammad; Tabassum, Saira; Zia, Muhammad

    2016-11-01

    Different biological activities of capped and uncapped ZnO nanoparticles were investigated, and the effects of potential capping agents on these biological activities were studied. ZnO nanoparticles were synthesized and capped by polyethylene glycol (PEG) and polyvinyl pyrrolidone (PVP) using a simple chemical method of co-precipitation. Characterization by X-ray diffraction (XRD), Fourier transform Infrared spectroscopy (FTIR) and UV-vis spectroscopy confirmed the crystallinity, size, functional group, and band gap of synthesized nanoparticles. Reduction in size occurred from 34 nm to 26 nm due to surfactant. Results of all biological activities indicated significantly higher values in capped as compared to uncapped nanoparticles. Antibacterial activity against Staphylococcus aureus (ATCC 6538), Bacillus subtilis (ATCC 6633), Escherichia coli (ATCC15224), and Acetobacter was obtained. This activity was more prominent against Gram-positive bacteria, and ZnO-PVP nanoparticles elucidated highest antibacterial activity (zone of inhibition 17 mm) against Gram-positive, Bacillus subtilis species. Antioxidant activities including total flavonoid content, total phenolic content, total antioxidant capacity, total reducing power and %age inhibition of DPPH, and antidiabetic activity against α-amylase enzyme found to be exhibited highest by ZnO-PEG nanoparticles.

  15. Performance of Traditional and Molecular Methods for Detecting Biological Agents in Drinking Water

    Science.gov (United States)

    Francy, Donna S.; Bushon, Rebecca N.; Brady, Amie M.G.; Bertke, Erin E.; Kephart, Christopher M.; Likirdopulos, Christina A.; Mailot, Brian E.; Schaefer, Frank W.; Lindquist, H.D. Alan

    2009-01-01

    To reduce the impact from a possible bioterrorist attack on drinking-water supplies, analytical methods are needed to rapidly detect the presence of biological agents in water. To this end, 13 drinking-water samples were collected at 9 water-treatment plants in Ohio to assess the performance of a molecular method in comparison to traditional analytical methods that take longer to perform. Two 100-liter samples were collected at each site during each sampling event; one was seeded in the laboratory with six biological agents - Bacillus anthracis (B. anthracis), Burkholderia cepacia (as a surrogate for Bu. pseudomallei), Francisella tularensis (F. tularensis), Salmonella Typhi (S. Typhi), Vibrio cholerae (V. cholerae), and Cryptospordium parvum (C. parvum). The seeded and unseeded samples were processed by ultrafiltration and analyzed by use of quantiative polymerase chain reaction (qPCR), a molecular method, and culture methods for bacterial agents or the immunomagnetic separation/fluorescent antibody (IMS/FA) method for C. parvum as traditional methods. Six replicate seeded samples were also processed and analyzed. For traditional methods, recoveries were highly variable between samples and even between some replicate samples, ranging from below detection to greater than 100 percent. Recoveries were significantly related to water pH, specific conductance, and dissolved organic carbon (DOC) for all bacteria combined by culture methods, but none of the water-quality characteristics tested were related to recoveries of C. parvum by IMS/FA. Recoveries were not determined by qPCR because of problems in quantifying organisms by qPCR in the composite seed. Instead, qPCR results were reported as detected, not detected (no qPCR signal), or +/- detected (Cycle Threshold or 'Ct' values were greater than 40). Several sample results by qPCR were omitted from the dataset because of possible problems with qPCR reagents, primers, and probes. For the remaining 14 qPCR results

  16. Biological control of the terrestrial carbon sink

    Science.gov (United States)

    Schulze, E.-D.

    2006-03-01

    This lecture reviews the past (since 1964 when the International Biological Program began) and the future of our understanding of terrestrial carbon fluxes with focus on photosynthesis, respiration, primary-, ecosystem-, and biome-productivity. Photosynthetic capacity is related to the nitrogen concentration of leaves, but the capacity is only rarely reached under field conditions. Average rates of photosynthesis and stomatal conductance are closely correlated and operate near 50% of their maximal rate, with light being the limiting factor in humid regions and air humidity and soil water the limiting factor in arid climates. Leaf area is the main factor to extrapolate from leaves to canopies, with maximum surface conductance being dependent on leaf level stomatal conductance. Additionally, gas exchange depends also on rooting depth which determines the water and nutrient availability and on mycorrhizae which regulate the nutrient status. An important anthropogenic disturbance is the nitrogen uptake from air pollutants, which is not balanced by cation uptake from roots and this may lead to damage and breakdown of the plant cover. Photosynthesis is the main carbon input into ecosystems, but it alone does not represent the ecosystem carbon balance, which is determined by respiration of various kinds. Plant respiration and photosynthesis determine growth (net primary production) and microbial respiration balances the net ecosystem flux. In a spruce forest, 30% of the assimilatory carbon gain is used for respiration of needles, 20% is used for respiration in stems. Soil respiration is about 50% the carbon gain, half of which is root respiration, half is microbial respiration. In addition, disturbances lead to carbon losses, where fire, harvest and grazing bypass the chain of respiration. In total, the carbon balance at the biome level is only about 1% of the photosynthetic carbon input, or may indeed become negative. The recent observed increase in plant growth has

  17. Biological control of the terrestrial carbon sink

    Directory of Open Access Journals (Sweden)

    E.-D. Schulze

    2006-01-01

    Full Text Available This lecture reviews the past (since 1964 when the International Biological Program began and the future of our understanding of terrestrial carbon fluxes with focus on photosynthesis, respiration, primary-, ecosystem-, and biome-productivity. Photosynthetic capacity is related to the nitrogen concentration of leaves, but the capacity is only rarely reached under field conditions. Average rates of photosynthesis and stomatal conductance are closely correlated and operate near 50% of their maximal rate, with light being the limiting factor in humid regions and air humidity and soil water the limiting factor in arid climates. Leaf area is the main factor to extrapolate from leaves to canopies, with maximum surface conductance being dependent on leaf level stomatal conductance. Additionally, gas exchange depends also on rooting depth which determines the water and nutrient availability and on mycorrhizae which regulate the nutrient status. An important anthropogenic disturbance is the nitrogen uptake from air pollutants, which is not balanced by cation uptake from roots and this may lead to damage and breakdown of the plant cover. Photosynthesis is the main carbon input into ecosystems, but it alone does not represent the ecosystem carbon balance, which is determined by respiration of various kinds. Plant respiration and photosynthesis determine growth (net primary production and microbial respiration balances the net ecosystem flux. In a spruce forest, 30% of the assimilatory carbon gain is used for respiration of needles, 20% is used for respiration in stems. Soil respiration is about 50% the carbon gain, half of which is root respiration, half is microbial respiration. In addition, disturbances lead to carbon losses, where fire, harvest and grazing bypass the chain of respiration. In total, the carbon balance at the biome level is only about 1% of the photosynthetic carbon input, or may indeed become negative. The recent observed increase in

  18. Use of rhizobacteria and endophytes for biological control of weeds

    Directory of Open Access Journals (Sweden)

    Trognitz, Friederike

    2014-02-01

    Full Text Available Weeds cause severe yield losses in agriculture, with a maximum estimate of 34% of yield loss worldwide due to competition between the crops and the weeds for nutrition, light and humidity (OERKE, 2006. Invasive plants contribute partially to other problems. The pollen of common ragweed, Ambrosia artemisiifolia L., for example, is five times more allergenic than grass pollen; already ten pollen grains per m3 air can trigger allergy in sensitized patients, including rhinitis, conjunctivitis and asthma. This neophyte from America has extended the season of allergy in European patients to October. Common ragweed is currently most frequent in Hungary, France and Italy. In Austria, ragweed populations along roads have increased dramatically since 2000. The effective means to control this weed of the Asteraceae family are limited; a single plant can produce up to 6000 seeds which stay in the soil for 40 years. Control using selective herbicides is not possible within stands of the Asteraceae member sunflower. Efforts to use herbivore insects as biological control agents also failed due to the unavailability of insects specializing on this ragweed. The use of plant-associated rhizobacteria and endophytes as bio-herbicides offers a novel alternative to conventional methods. By analogy to experiences from other plant-microbe systems, the chances to find microbes of the desired characteristics are highest when isolating and testing specimens directly from ragweed plants. These organisms often have an extremely narrow host range that permits their use for the control of among several even closely related plant species growing together in a field.

  19. EFSA Panel on Biological Hazards (BIOHAZ); Scientific Opinion on the maintenance of the list of QPS biological agents intentionally added to food and feed (2011 update)

    DEFF Research Database (Denmark)

    Hald, Tine

    EFSA is requested to assess the safety of a broad range of biological agents (including microorganisms and viruses) in the context of notifications for market authorisation as sources of food and feed additives, enzymes and plant protection products. The qualified presumption of safety (QPS......) assessment was developed by EFSA for its own use to provide a generic risk assessment approach applicable across EFSA’s scientific Panels, for biological agents notified for intentional use in the whole food chain. The safety of unambiguously defined biological agents at the highest taxonomic unit...... recommendations. The anamorph yeast form Phaffia rhodozyma of Xanthophyllomyces dendrorhous was included on the QPS list and to the qualification for yeasts ‘absence of resistance to antimycotics used for medical treatment of yeast infections’, the sentence was added that ‘in the case of Saccharomyces cerevisiae...

  20. Biology and control of Varroa destructor.

    Science.gov (United States)

    Rosenkranz, Peter; Aumeier, Pia; Ziegelmann, Bettina

    2010-01-01

    The ectoparasitic honey bee mite Varroa destructor was originally confined to the Eastern honey bee Apis cerana. After a shift to the new host Apis mellifera during the first half of the last century, the parasite dispersed world wide and is currently considered the major threat for apiculture. The damage caused by Varroosis is thought to be a crucial driver for the periodical colony losses in Europe and the USA and regular Varroa treatments are essential in these countries. Therefore, Varroa research not only deals with a fascinating host-parasite relationship but also has a responsibility to find sustainable solutions for the beekeeping. This review provides a survey of the current knowledge in the main fields of Varroa research including the biology of the mite, damage to the host, host tolerance, tolerance breeding and Varroa treatment. We first present a general view on the functional morphology and on the biology of the Varroa mite with special emphasis on host-parasite interactions during reproduction of the female mite. The pathology section describes host damage at the individual and colony level including the problem of transmission of secondary infections by the mite. Knowledge of both the biology and the pathology of Varroa mites is essential for understanding possible tolerance mechanisms in the honey bee host. We comment on the few examples of natural tolerance in A. mellifera and evaluate recent approaches to the selection of Varroa tolerant honey bees. Finally, an extensive listing and critical evaluation of chemical and biological methods of Varroa treatments is given. This compilation of present-day knowledge on Varroa honey bee interactions emphasizes that we are still far from a solution for Varroa infestation and that, therefore, further research on mite biology, tolerance breeding, and Varroa treatment is urgently needed.

  1. Distributed Cooperative Control of Nonlinear and Non-identical Multi-agent Systems

    DEFF Research Database (Denmark)

    Bidram, Ali; Lewis, Frank; Davoudi, Ali

    2013-01-01

    to the synchronization problem for an identical linear multi-agent system. The controller for each agent is designed to be fully distributed, such that each agent only requires its own information and the information of its neighbors. The proposed control method is exploited to implement the secondary voltage control......This paper exploits input-output feedback linearization technique to implement distributed cooperative control of multi-agent systems with nonlinear and non-identical dynamics. Feedback linearization transforms the synchronization problem for a nonlinear and heterogeneous multi-agent system...... for electric power microgrids. The effectiveness of the proposed control is verified by simulating a microgrid test system....

  2. Love-Wave Sensors Combined with Microfluidics for Fast Detection of Biological Warfare Agents

    Science.gov (United States)

    Matatagui, Daniel; Fontecha, José Luis; Fernández, María Jesús; Gràcia, Isabel; Cané, Carles; Santos, José Pedro; Horrillo, María Carmen

    2014-01-01

    The following paper examines a time-efficient method for detecting biological warfare agents (BWAs). The method is based on a system of a Love-wave immunosensor combined with a microfluidic chip which detects BWA samples in a dynamic mode. In this way a continuous flow-through of the sample is created, promoting the reaction between antigen and antibody and allowing a fast detection of the BWAs. In order to prove this method, static and dynamic modes have been simulated and different concentrations of BWA simulants have been tested with two immunoreactions: phage M13 has been detected using the mouse monoclonal antibody anti-M13 (AM13), and the rabbit immunoglobulin (Rabbit IgG) has been detected using the polyclonal antibody goat anti-rabbit (GAR). Finally, different concentrations of each BWA simulants have been detected with a fast response time and a desirable level of discrimination among them has been achieved. PMID:25029282

  3. Love-Wave Sensors Combined with Microfluidics for Fast Detection of Biological Warfare Agents

    Directory of Open Access Journals (Sweden)

    Daniel Matatagui

    2014-07-01

    Full Text Available The following paper examines a time-efficient method for detecting biological warfare agents (BWAs. The method is based on a system of a Love-wave immunosensor combined with a microfluidic chip which detects BWA samples in a dynamic mode. In this way a continuous flow-through of the sample is created, promoting the reaction between antigen and antibody and allowing a fast detection of the BWAs. In order to prove this method, static and dynamic modes have been simulated and different concentrations of BWA simulants have been tested with two immunoreactions: phage M13 has been detected using the mouse monoclonal antibody anti-M13 (AM13, and the rabbit immunoglobulin (Rabbit IgG has been detected using the polyclonal antibody goat anti-rabbit (GAR. Finally, different concentrations of each BWA simulants have been detected with a fast response time and a desirable level of discrimination among them has been achieved.

  4. Love-wave sensors combined with microfluidics for fast detection of biological warfare agents.

    Science.gov (United States)

    Matatagui, Daniel; Fontecha, José Luis; Fernández, María Jesús; Gràcia, Isabel; Cané, Carles; Santos, José Pedro; Horrillo, María Carmen

    2014-07-15

    The following paper examines a time-efficient method for detecting biological warfare agents (BWAs). The method is based on a system of a Love-wave immunosensor combined with a microfluidic chip which detects BWA samples in a dynamic mode. In this way a continuous flow-through of the sample is created, promoting the reaction between antigen and antibody and allowing a fast detection of the BWAs. In order to prove this method, static and dynamic modes have been simulated and different concentrations of BWA simulants have been tested with two immunoreactions: phage M13 has been detected using the mouse monoclonal antibody anti-M13 (AM13), and the rabbit immunoglobulin (Rabbit IgG) has been detected using the polyclonal antibody goat anti-rabbit (GAR). Finally, different concentrations of each BWA simulants have been detected with a fast response time and a desirable level of discrimination among them has been achieved.

  5. Biological Control of Meloidogyne hapla Using an Antagonistic Bacterium

    Directory of Open Access Journals (Sweden)

    Jiyeong Park

    2014-09-01

    Full Text Available We examined the efficacy of a bacterium for biocontrol of the root-knot nematode (RKN Meloidogyne hapla in carrot (Daucus carota subsp. sativus and tomato (Solanum lycopersicum. Among 542 bacterial isolates from various soils and plants, the highest nematode mortality was observed for treatments with isolate C1-7, which was identified as Bacillus cereus based on cultural and morphological characteristics, the Biolog program, and 16S rRNA sequencing analyses. The population density and the nematicidal activity of B. cereus C1-7 remained high until the end of culture in brain heart infusion broth, suggesting that it may have sustainable biocontrol potential. In pot experiments, the biocontrol efficacy of B. cereus C1-7 was high, showing complete inhibition of root gall or egg mass formation by RKN in carrot and tomato plants, and subsequently reducing RKN damage and suppressing nematode population growth, respectively. Light microscopy of RKN-infected carrot root tissues treated with C1-7 showed reduced formation of gall cells and fully developed giant cells, while extensive gall cells and fully mature giant cells with prominent cell wall ingrowths formed in the untreated control plants infected with RKNs. These histopathological characteristics may be the result of residual or systemic biocontrol activity of the bacterium, which may coincide with the biocontrol efficacies of nematodes in pots. These results suggest that B. cereus C1-7 can be used as a biocontrol agent for M. hapla.

  6. Polymers as directing agents for motions of chemical and biological species

    Science.gov (United States)

    Tanyeri, Nihan Yonet

    This thesis involves descriptions of solid surface modifications with various polymeric materials which were used as a guiding agent for motion of chemical and biological species. Quasi-two dimensional poly(oligoethylene glycol) acrylate polymer brush based molecular conduits have been designed with the goal of regulating and controlling the diffusive transport of molecular, e.g. organic dyes, and ionic species, e.g. AuCl4-, and Cu2+ ions, along predefined 2-D pathways. The transport of these chemical species has been examined by both fluorescence and dark field microscopy. The polymer brushes were formed through microcontact printing of an initiator, followed by surface-initiated Atom Transfer Radical Polymerization (SI-ATRP). SI-ATRP enables both 2-D patterning with a resolution of about 1 micrometer, and control over the resultant polymer brush thickness (which was varied from 10-100 nm). A hydrophilic poly(oligoethylene glycol) acrylate brushe was selected because of its potential to dissolve a wide range of hydrophilic species. The transport of fluorescent species can be directly followed. A non-lithographic fabrication method was developed for mufluidic devices used in the diffusion studies. Singular channel mufluidic device was utilized to study the directed organic dye diffusion. The AuCl4-, and Cu 2+ ion transport was studied by designing molecular devices with two mufluidic channels. We have demonstrated that the various species of interest diffuse much more rapidly along the predefined pathway than along the bare (polymer brush free) regions of the substrate, demonstrating that diffusive conduits for molecular transport can indeed be formed. The protein resistance of poly(N-isopropylacrylamide) (PNIPAM) brushes grafted from silicon wafers was investigated as a function of the chain molecular weight, grafting density, and temperature. Above the lower critical solution temperature (LCST) of 32°C, the collapse of the water swollen chains, determined by

  7. Chemical biology drug sensitivity screen identifies sunitinib as synergistic agent with disulfiram in prostate cancer cells.

    Directory of Open Access Journals (Sweden)

    Kirsi Ketola

    Full Text Available BACKGROUND: Current treatment options for castration- and treatment-resistant prostate cancer are limited and novel approaches are desperately needed. Our recent results from a systematic chemical biology sensitivity screen covering most known drugs and drug-like molecules indicated that aldehyde dehydrogenase inhibitor disulfiram is one of the most potent cancer-specific inhibitors of prostate cancer cell growth, including TMPRSS2-ERG fusion positive cancers. However, the results revealed that disulfiram alone does not block tumor growth in vivo nor induce apoptosis in vitro, indicating that combinatorial approaches may be required to enhance the anti-neoplastic effects. METHODS AND FINDINGS: In this study, we utilized a chemical biology drug sensitivity screen to explore disulfiram mechanistic details and to identify compounds potentiating the effect of disulfiram in TMPRSS2-ERG fusion positive prostate cancer cells. In total, 3357 compounds including current chemotherapeutic agents as well as drug-like small molecular compounds were screened alone and in combination with disulfiram. Interestingly, the results indicated that androgenic and antioxidative compounds antagonized disulfiram effect whereas inhibitors of receptor tyrosine kinase, proteasome, topoisomerase II, glucosylceramide synthase or cell cycle were among compounds sensitizing prostate cancer cells to disulfiram. The combination of disulfiram and an antiangiogenic agent sunitinib was studied in more detail, since both are already in clinical use in humans. Disulfiram-sunitinib combination induced apoptosis and reduced androgen receptor protein expression more than either of the compounds alone. Moreover, combinatorial exposure reduced metastatic characteristics such as cell migration and 3D cell invasion as well as induced epithelial differentiation shown as elevated E-cadherin expression. CONCLUSIONS: Taken together, our results propose novel combinatorial approaches to inhibit

  8. Chemical Biology Drug Sensitivity Screen Identifies Sunitinib as Synergistic Agent with Disulfiram in Prostate Cancer Cells

    Science.gov (United States)

    Ketola, Kirsi; Kallioniemi, Olli; Iljin, Kristiina

    2012-01-01

    Background Current treatment options for castration- and treatment-resistant prostate cancer are limited and novel approaches are desperately needed. Our recent results from a systematic chemical biology sensitivity screen covering most known drugs and drug-like molecules indicated that aldehyde dehydrogenase inhibitor disulfiram is one of the most potent cancer-specific inhibitors of prostate cancer cell growth, including TMPRSS2-ERG fusion positive cancers. However, the results revealed that disulfiram alone does not block tumor growth in vivo nor induce apoptosis in vitro, indicating that combinatorial approaches may be required to enhance the anti-neoplastic effects. Methods and Findings In this study, we utilized a chemical biology drug sensitivity screen to explore disulfiram mechanistic details and to identify compounds potentiating the effect of disulfiram in TMPRSS2-ERG fusion positive prostate cancer cells. In total, 3357 compounds including current chemotherapeutic agents as well as drug-like small molecular compounds were screened alone and in combination with disulfiram. Interestingly, the results indicated that androgenic and antioxidative compounds antagonized disulfiram effect whereas inhibitors of receptor tyrosine kinase, proteasome, topoisomerase II, glucosylceramide synthase or cell cycle were among compounds sensitizing prostate cancer cells to disulfiram. The combination of disulfiram and an antiangiogenic agent sunitinib was studied in more detail, since both are already in clinical use in humans. Disulfiram-sunitinib combination induced apoptosis and reduced androgen receptor protein expression more than either of the compounds alone. Moreover, combinatorial exposure reduced metastatic characteristics such as cell migration and 3D cell invasion as well as induced epithelial differentiation shown as elevated E-cadherin expression. Conclusions Taken together, our results propose novel combinatorial approaches to inhibit prostate cancer cell

  9. A Systematic Screen of FDA-Approved Drugs for Inhibitors of Biological Threat Agents

    Science.gov (United States)

    Madrid, Peter B.; Chopra, Sidharth; Manger, Ian D.; Gilfillan, Lynne; Keepers, Tiffany R.; Shurtleff, Amy C.; Green, Carol E.; Iyer, Lalitha V.; Dilks, Holli Hutcheson; Davey, Robert A.; Kolokoltsov, Andrey A.; Carrion, Ricardo; Patterson, Jean L.; Bavari, Sina; Panchal, Rekha G.; Warren, Travis K.; Wells, Jay B.; Moos, Walter H.; Burke, RaeLyn L.; Tanga, Mary J.

    2013-01-01

    Background The rapid development of effective medical countermeasures against potential biological threat agents is vital. Repurposing existing drugs that may have unanticipated activities as potential countermeasures is one way to meet this important goal, since currently approved drugs already have well-established safety and pharmacokinetic profiles in patients, as well as manufacturing and distribution networks. Therefore, approved drugs could rapidly be made available for a new indication in an emergency. Methodology/Principal Findings A large systematic effort to determine whether existing drugs can be used against high containment bacterial and viral pathogens is described. We assembled and screened 1012 FDA-approved drugs for off-label broad-spectrum efficacy against Bacillus anthracis; Francisella tularensis; Coxiella burnetii; and Ebola, Marburg, and Lassa fever viruses using in vitro cell culture assays. We found a variety of hits against two or more of these biological threat pathogens, which were validated in secondary assays. As expected, antibiotic compounds were highly active against bacterial agents, but we did not identify any non-antibiotic compounds with broad-spectrum antibacterial activity. Lomefloxacin and erythromycin were found to be the most potent compounds in vivo protecting mice against Bacillus anthracis challenge. While multiple virus-specific inhibitors were identified, the most noteworthy antiviral compound identified was chloroquine, which disrupted entry and replication of two or more viruses in vitro and protected mice against Ebola virus challenge in vivo. Conclusions/Significance The feasibility of repurposing existing drugs to face novel threats is demonstrated and this represents the first effort to apply this approach to high containment bacteria and viruses. PMID:23577127

  10. A systematic screen of FDA-approved drugs for inhibitors of biological threat agents.

    Directory of Open Access Journals (Sweden)

    Peter B Madrid

    Full Text Available BACKGROUND: The rapid development of effective medical countermeasures against potential biological threat agents is vital. Repurposing existing drugs that may have unanticipated activities as potential countermeasures is one way to meet this important goal, since currently approved drugs already have well-established safety and pharmacokinetic profiles in patients, as well as manufacturing and distribution networks. Therefore, approved drugs could rapidly be made available for a new indication in an emergency. METHODOLOGY/PRINCIPAL FINDINGS: A large systematic effort to determine whether existing drugs can be used against high containment bacterial and viral pathogens is described. We assembled and screened 1012 FDA-approved drugs for off-label broad-spectrum efficacy against Bacillus anthracis; Francisella tularensis; Coxiella burnetii; and Ebola, Marburg, and Lassa fever viruses using in vitro cell culture assays. We found a variety of hits against two or more of these biological threat pathogens, which were validated in secondary assays. As expected, antibiotic compounds were highly active against bacterial agents, but we did not identify any non-antibiotic compounds with broad-spectrum antibacterial activity. Lomefloxacin and erythromycin were found to be the most potent compounds in vivo protecting mice against Bacillus anthracis challenge. While multiple virus-specific inhibitors were identified, the most noteworthy antiviral compound identified was chloroquine, which disrupted entry and replication of two or more viruses in vitro and protected mice against Ebola virus challenge in vivo. CONCLUSIONS/SIGNIFICANCE: The feasibility of repurposing existing drugs to face novel threats is demonstrated and this represents the first effort to apply this approach to high containment bacteria and viruses.

  11. Bioluminescent bioreporter assays for targeted detection of chemical and biological agents

    Science.gov (United States)

    Ripp, Steven; Jegier, Pat; Johnson, Courtney; Moser, Scott; Islam, Syed; Sayler, Gary

    2008-04-01

    Bioluminescent bioreporters carrying the bacterial lux gene cassette have been well established for the sensing and monitoring of select chemical agents. Their ability to generate target specific visible light signals with no requirement for extraneous additions of substrate or other hands-on manipulations affords a real-time, repetitive assaying technique that is remarkable in its simplicity and accuracy. Although the predominant application of lux-based bioluminescent bioreporters has been towards chemical compound detection, novel genetic engineering schemes are yielding a variety of new bioreporter systems that extend the lux sensing mechanism beyond mere analyte discrimination. For example, the unique specificity of bacteriophage (bacterial viruses) has been exploited in lux bioluminescent assays for specific identification of foodborne bacterial pathogens such as Escherichia coli O157:H7. With the concurrent ability to interface bioluminescent bioreporter assays onto integrated circuit microluminometers (BBICs; bioluminescent bioreporter integrated circuits), the potential exists for the development of sentinel microchips that can function as environmental monitors for multiplexed recognition of chemical and biological agents in air, food, and water. The size and portability of BBIC biosensors may ultimately provide a deployable, interactive network sensing technology adaptable towards chem/bio defense.

  12. Fusion of chemical, biological, and meteorological observations for agent source term estimation and hazard refinement

    Science.gov (United States)

    Bieringer, Paul E.; Rodriguez, Luna M.; Sykes, Ian; Hurst, Jonathan; Vandenberghe, Francois; Weil, Jeffrey; Bieberbach, George, Jr.; Parker, Steve; Cabell, Ryan

    2011-05-01

    Chemical and biological (CB) agent detection and effective use of these observations in hazard assessment models are key elements of our nation's CB defense program that seeks to ensure that Department of Defense (DoD) operations are minimally affected by a CB attack. Accurate hazard assessments rely heavily on the source term parameters necessary to characterize the release in the transport and dispersion (T&D) simulation. Unfortunately, these source parameters are often not known and based on rudimentary assumptions. In this presentation we describe an algorithm that utilizes variational data assimilation techniques to fuse CB and meteorological observations to characterize agent release source parameters and provide a refined hazard assessment. The underlying algorithm consists of a combination of modeling systems, including the Second order Closure Integrated PUFF model (SCIPUFF), its corresponding Source Term Estimation (STE) model, a hybrid Lagrangian-Eulerian Plume Model (LEPM), its formal adjoint, and the software infrastructure necessary to link them. SCIPUFF and its STE model are used to calculate a "first guess" source estimate. The LEPM and corresponding adjoint are then used to iteratively refine this release source estimate using variational data assimilation techniques. This algorithm has undergone preliminary testing using virtual "single realization" plume release data sets from the Virtual THreat Response Emulation and Analysis Testbed (VTHREAT) and data from the FUSION Field Trials 2007 (FFT07). The end-to-end prototype of this system that has been developed to illustrate its use within the United States (US) Joint Effects Model (JEM) will be demonstrated.

  13. Nanoparticle-labeled DNA capture elements for detection and identification of biological agents

    Science.gov (United States)

    Kiel, Johnathan L.; Holwitt, Eric A.; Parker, Jill E.; Vivekananda, Jeevalatha; Franz, Veronica

    2004-12-01

    Aptamers, synthetic DNA capture elements (DCEs), can be made chemically or in genetically engineered bacteria. DNA capture elements are artificial DNA sequences, from a random pool of sequences, selected for their specific binding to potential biological warfare or terrorism agents. These sequences were selected by an affinity method using filters to which the target agent was attached and the DNA isolated and amplified by polymerase chain reaction (PCR) in an iterative, increasingly stringent, process. The probes can then be conjugated to Quantum Dots and super paramagnetic nanoparticles. The former provide intense, bleach-resistant fluorescent detection of bioagent and the latter provide a means to collect the bioagents with a magnet. The fluorescence can be detected in a flow cytometer, in a fluorescence plate reader, or with a fluorescence microscope. To date, we have made DCEs to Bacillus anthracis spores, Shiga toxin, Venezuelan Equine Encephalitis (VEE) virus, and Francisella tularensis. DCEs can easily distinguish Bacillus anthracis from its nearest relatives, Bacillus cereus and Bacillus thuringiensis. Development of a high through-put process is currently being investigated.

  14. Application of superconducting technologies as chemical/biological agent electronic eyes

    Science.gov (United States)

    Savoy, Steven M.; Eames, Sara J.; Jurbergs, David C.; Zhao, Jianai; McDevitt, John T.; Sobel, Annette L.

    1997-01-01

    High temperature superconductors provide enhanced sensitivity capabilities as chemical/biological agent detectors. State-of-the-art advances in ruggedizing superconducting platforms make them much more robust for field applications. In addition, microminiaturization and advances in refrigeration have enabled the systems engineering of portable, durable, survivable, low power requirement devices. This presentation describes a prototype system employing YBCO (yttrium barium copper oxide) superconducting quantum interference devices (SQUIDS) with specific biolayer detection dye coatings. These devices may be deployed as specific stand-off detectors, or potentially reconfigured as point sensors. A library of pattern recognition algorithms provides the reference template for the system. The human-system interface will provide a 'yes/no' agent confirmation for the environment being queried, and associated confidence value. This prototype detection system has great potential for deployment in support of hostage rescue/rapid response teams, DMAT, and urban search and rescue. The preparation and characterization of a new generation of optical sensors fabricated from high-temperature superconductor (HTSC) thin films is reported herein. These new hybrid devices are fashioned using HTSC thin films which are coated with organic dye overlayers. These systems are shown to respond selectively to those wavelengths which are absorbed strongly by the molecular dye. Methods for fabricating the superconductor element and depositing the dye layer are discussed. Moreover, resistivity versus temperature measurements before and after dye deposition are utilized to characterize these hybrid structures. The unique optical response properties of these hybrid sensors are also detailed.

  15. Invasive Species Biology, Control, and Research. Part 2. Multiflora Rose (Rosa multiflora)

    Science.gov (United States)

    2008-11-01

    this agent should be considered in concert with other biological control methods. The dying canes are incapable of asexual reproduction via layering...two, Multiflora Rose seedlings grow inconspicuously, but quickly become well anchored. Multiflora Rose reproduces asexually by suckering and...mowing the remaining topgrowth eliminates any remaining live plant parts that could asexually reproduce. ERDC TR-08-11 8 Table 1. Herbicides that

  16. Recent Advances in Biological Control of Pest Insects by Using Viruses in China

    Institute of Scientific and Technical Information of China (English)

    Xiu-lian SUN; Hui-yin PENG

    2007-01-01

    Insect viruses are attractive as biological control agents and could be a feasible alternative to chemical insecticides in the management of insect infestations. This review describes recent advances in the development of wild-type and genetically modified viruses as insecticides. A new strategy of application of insect viruses in China is reviewed. Also, the assessment of biosafety of genetically modified Helicoverpa armigera Nucleopolyhedovirus (HearNPV) is emphasized as a case-study.

  17. BSim: an agent-based tool for modeling bacterial populations in systems and synthetic biology.

    Directory of Open Access Journals (Sweden)

    Thomas E Gorochowski

    Full Text Available Large-scale collective behaviors such as synchronization and coordination spontaneously arise in many bacterial populations. With systems biology attempting to understand these phenomena, and synthetic biology opening up the possibility of engineering them for our own benefit, there is growing interest in how bacterial populations are best modeled. Here we introduce BSim, a highly flexible agent-based computational tool for analyzing the relationships between single-cell dynamics and population level features. BSim includes reference implementations of many bacterial traits to enable the quick development of new models partially built from existing ones. Unlike existing modeling tools, BSim fully considers spatial aspects of a model allowing for the description of intricate micro-scale structures, enabling the modeling of bacterial behavior in more realistic three-dimensional, complex environments. The new opportunities that BSim opens are illustrated through several diverse examples covering: spatial multicellular computing, modeling complex environments, population dynamics of the lac operon, and the synchronization of genetic oscillators. BSim is open source software that is freely available from http://bsim-bccs.sf.net and distributed under the Open Source Initiative (OSI recognized MIT license. Developer documentation and a wide range of example simulations are also available from the website. BSim requires Java version 1.6 or higher.

  18. Comparing Effects of Biologic Agents in Treating Patients with Rheumatoid Arthritis: A Multiple Treatment Comparison Regression Analysis.

    Directory of Open Access Journals (Sweden)

    Ingunn Fride Tvete

    Full Text Available Rheumatoid arthritis patients have been treated with disease modifying anti-rheumatic drugs (DMARDs and the newer biologic drugs. We sought to compare and rank the biologics with respect to efficacy. We performed a literature search identifying 54 publications encompassing 9 biologics. We conducted a multiple treatment comparison regression analysis letting the number experiencing a 50% improvement on the ACR score be dependent upon dose level and disease duration for assessing the comparable relative effect between biologics and placebo or DMARD. The analysis embraced all treatment and comparator arms over all publications. Hence, all measured effects of any biologic agent contributed to the comparison of all biologic agents relative to each other either given alone or combined with DMARD. We found the drug effect to be dependent on dose level, but not on disease duration, and the impact of a high versus low dose level was the same for all drugs (higher doses indicated a higher frequency of ACR50 scores. The ranking of the drugs when given without DMARD was certolizumab (ranked highest, etanercept, tocilizumab/ abatacept and adalimumab. The ranking of the drugs when given with DMARD was certolizumab (ranked highest, tocilizumab, anakinra/rituximab, golimumab/ infliximab/ abatacept, adalimumab/ etanercept [corrected]. Still, all drugs were effective. All biologic agents were effective compared to placebo, with certolizumab the most effective and adalimumab (without DMARD treatment and adalimumab/ etanercept (combined with DMARD treatment the least effective. The drugs were in general more effective, except for etanercept, when given together with DMARDs.

  19. Synthesis and biological activity of trans-tiliroside derivatives as potent anti-diabetic agents.

    Science.gov (United States)

    Zhu, Yujin; Zhang, Yanjun; Liu, Yi; Chu, Hongwan; Duan, Hongquan

    2010-12-10

    A set of novel trans-tiliroside derivatives were synthesized. The structures of the derivatives were identified by their IR, 1H-NMR, and MS spectra analysis. Their anti-diabetic activities were evaluated on the insulin resistant (IR) HepG2 cell model. As a result, compounds 7a, 7c, 7h, and trans-tiliroside exhibited significant glucose consumption-enhancing effects in IR-HepG2 cells compared with the positive control (metformin). This research provides useful clues for further design and discovery of anti-diabetic agents.

  20. Synthesis and Biological Activity of trans-Tiliroside Derivatives as Potent Anti-Diabetic Agents

    Directory of Open Access Journals (Sweden)

    Yi Liu

    2010-12-01

    Full Text Available A set of novel trans-tiliroside derivatives were synthesized. The structures of the derivatives were identified by their IR, 1H-NMR, and MS spectra analysis. Their anti-diabetic activities were evaluated on the insulin resistant (IR HepG2 cell model. As a result, compounds 7a, 7c, 7h, and trans-tiliroside exhibited significant glucose consumption-enhancing effects in IR-HepG2 cells compared with the positive control (metformin. This research provides useful clues for further design and discovery of anti-diabetic agents.

  1. Microencapsulation of Self Healing Agents for Corrosion Control Coatings

    Science.gov (United States)

    Jolley, S. T.; Li, W.; Buhrow, J. W.; Calle, L. M.

    2011-01-01

    Corrosion, the environmentally induced degradation of materials, is a very costly problem that has a major impact on the global economy. Results from a 2-year breakthrough study released in 2002 by the U.S. Federal Highway Administration (FHWA) showed that the total annual estimated direct cost associated with metallic corrosion in nearly every U.S. industry sector was a staggering $276 billion, approximately 3.1% of the nation's Gross Domestic Product (GOP). Corrosion protective coatings are widely used to protect metallic structures from the detrimental effects of corrosion but their effectiveness can be seriously compromised by mechanical damage, such as a scratch, that exposes the metallic substrate. The incorporation of a self healing mechanism into a corrosion control coating would have the potential to significantly increase its effectiveness and useful lifetime. This paper describes work performed to incorporate a number of microcapsule-based self healing systems into corrosion control coatings. The work includes the preparation and evaluation of self-healing systems based on curable epoxy, acrylate, and siloxane resins, as well as, microencapsulated systems based on passive, solvent born, healing agent delivery. The synthesis and optimization of microcapsule-based self healing systems for thin coating (less than 100 micron) will be presented.

  2. Encyrtid parasitoids of soft scale insects: biology, behavior, and their use in biological control.

    Science.gov (United States)

    Kapranas, Apostolos; Tena, Alejandro

    2015-01-07

    Parasitoids of the hymenopterous family Encyrtidae are one of the most important groups of natural enemies of soft scale insects and have been used extensively in biological control. We summarize existing knowledge of the biology, ecology, and behavior of these parasitoids and how it relates to biological control. Soft scale stage/size and phenology are important determinants of host range and host utilization, which are key aspects in understanding how control by these parasitoids is exerted. Furthermore, the nutritional ecology of encyrtids and their physiological interactions with their hosts affect soft scale insect population dynamics. Lastly, the interactions among encyrtids, heteronomous parasitoids, and ants shape parasitoid species complexes and consequently have a direct impact on the biological control of soft scale insects.

  3. Identification of Bacillus strains for biological control of catfish pathogens.

    Directory of Open Access Journals (Sweden)

    Chao Ran

    Full Text Available Bacillus strains isolated from soil or channel catfish intestine were screened for their antagonism against Edwardsiella ictaluri and Aeromonas hydrophila, the causative agents of enteric septicemia of catfish (ESC and motile aeromonad septicaemia (MAS, respectively. Twenty one strains were selected and their antagonistic activity against other aquatic pathogens was also tested. Each of the top 21 strains expressed antagonistic activity against multiple aquatic bacterial pathogens including Edwardsiella tarda, Streptococcus iniae, Yersinia ruckeri, Flavobacterium columnare, and/or the oomycete Saprolegnia ferax. Survival of the 21 Bacillus strains in the intestine of catfish was determined as Bacillus CFU/g of intestinal tissue of catfish after feeding Bacillus spore-supplemented feed for seven days followed by normal feed for three days. Five Bacillus strains that showed good antimicrobial activity and intestinal survival were incorporated into feed in spore form at a dose of 8×10(7 CFU/g and fed to channel catfish for 14 days before they were challenged by E. ictaluri in replicate. Two Bacillus subtilis strains conferred significant benefit in reducing catfish mortality (P<0.05. A similar challenge experiment conducted in Vietnam with four of the five Bacillus strains also showed protective effects against E. ictaluri in striped catfish. Safety of the four strains exhibiting the strongest biological control in vivo was also investigated in terms of whether the strains contain plasmids or express resistance to clinically important antibiotics. The Bacillus strains identified from this study have good potential to mediate disease control as probiotic feed additives for catfish aquaculture.

  4. Diffuse large B-cell lymphoma associated with the use of biologic and other investigational agents: the importance of long-term post-marketing safety surveillance.

    Science.gov (United States)

    Goddard, Allison; Borovicka, Judy H; West, Dennis P; Evens, Andrew M; Laumann, Anne

    2011-01-01

    This case report describes a patient who developed diffuse large B-cell lymphoma (DLBCL) after receiving courses of two investigational biologic agents and cyclosporine followed by more than four years of subcutaneous efalizumab for the treatment of extensive chronic plaque psoriasis. Three years later, the patient remains free of lymphoma and his psoriasis is well controlled with thrice-weekly narrow-band ultraviolet phototherapy. This case emphasizes the importance of continued long-term post-marketing safety surveillance and the early reporting of all possible serious side effects, including cancers, related to the use of any newly available product. In particular, surveillance should focus on the immunomodulating biologic agents in order to identify possible dangerous sequelae.

  5. Distributed Model Predictive Control of the Multi-Agent Systems with Improving Control Performance

    Directory of Open Access Journals (Sweden)

    Wei Shanbi

    2012-01-01

    Full Text Available This paper addresses a distributed model predictive control (DMPC scheme for multiagent systems with improving control performance. In order to penalize the deviation of the computed state trajectory from the assumed state trajectory, the deviation punishment is involved in the local cost function of each agent. The closed-loop stability is guaranteed with a large weight for deviation punishment. However, this large weight leads to much loss of control performance. Hence, the time-varying compatibility constraints of each agent are designed to balance the closed-loop stability and the control performance, so that the closed-loop stability is achieved with a small weight for the deviation punishment. A numerical example is given to illustrate the effectiveness of the proposed scheme.

  6. Project Summary: Biology-Inspired Autonomous Control

    Science.gov (United States)

    2011-02-01

    relative high performance predictability currently associated with automated machines. Anyone who has walked a normally well behaved male dog in the...possibilities as well. Attitude control systems normally include proportional and integral control on sensed attitude, with damping and robustness provided...attacking predators. Some examples include red-wing black bird nest defense [1], meerkat predator mobbing [2], and predator identification in guppy schools

  7. Biological control of weeds release sites : Kulm Wetland Management District

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Table of release sites of insects for biological control of invasive plants at Kulm Wetland Management District (WMD). Insects were released on Kulm WMD to...

  8. Arms Control: US and International efforts to ban biological weapons

    Energy Technology Data Exchange (ETDEWEB)

    1992-12-01

    The Bacteriological (Biological) and Toxin Weapons Convention, the treaty that bans the development, production, and stockpiling and acquisition of biological weapons was opened for signature in 1972 and came into force in 1975 after being ratified by 22 governments, including the depository nations of the USA, the United Kingdom, and the former Soviet Union. In support of the Convention, the USA later established export controls on items used to make biological weapons. Further, in accordance with the 1990 President`s Enhanced Proliferation Control Initiative, actions were taken to redefine and expand US export controls, as well as to encourage multilateral controls through the Australia Group. Thus far, the Convention has not been effective in stopping the development of biological weapons. The principal findings as to the reasons of the failures of the Convention are found to be: the Convention lacks universality, compliance measures are effective, advantage of verification may outweigh disadvantages. Recommendations for mitigating these failures are outlined in this report.

  9. Biological control of tortricids and aphids in strawberries

    DEFF Research Database (Denmark)

    Sigsgaard, Lene; Enkegaard, Annie; Eilenberg, Jørgen;

    Cropping practice and biological control can contribute to reduced pesticide use in strawberries. Organic strawberries are less attacked by strawberry tortricid and buckwheat flower strips can augment its natural enemies. Against shallot aphid the two-spot ladybird is promising.......Cropping practice and biological control can contribute to reduced pesticide use in strawberries. Organic strawberries are less attacked by strawberry tortricid and buckwheat flower strips can augment its natural enemies. Against shallot aphid the two-spot ladybird is promising....

  10. Controllability and observability of Boolean networks arising from biology.

    Science.gov (United States)

    Li, Rui; Yang, Meng; Chu, Tianguang

    2015-02-01

    Boolean networks are currently receiving considerable attention as a computational scheme for system level analysis and modeling of biological systems. Studying control-related problems in Boolean networks may reveal new insights into the intrinsic control in complex biological systems and enable us to develop strategies for manipulating biological systems using exogenous inputs. This paper considers controllability and observability of Boolean biological networks. We propose a new approach, which draws from the rich theory of symbolic computation, to solve the problems. Consequently, simple necessary and sufficient conditions for reachability, controllability, and observability are obtained, and algorithmic tests for controllability and observability which are based on the Gröbner basis method are presented. As practical applications, we apply the proposed approach to several different biological systems, namely, the mammalian cell-cycle network, the T-cell activation network, the large granular lymphocyte survival signaling network, and the Drosophila segment polarity network, gaining novel insights into the control and/or monitoring of the specific biological systems.

  11. Spectroscopic characterization of biological agents using FTIR, normal Raman and surface-enhanced Raman spectroscopies

    Science.gov (United States)

    Luna-Pineda, Tatiana; Soto-Feliciano, Kristina; De La Cruz-Montoya, Edwin; Pacheco Londoño, Leonardo C.; Ríos-Velázquez, Carlos; Hernández-Rivera, Samuel P.

    2007-04-01

    FTIR, Raman spectroscopy and Surface Enhanced Raman Scattering (SERS) requires a minimum of sample allows fast identification of microorganisms. The use of this technique for characterizing the spectroscopic signatures of these agents and their stimulants has recently gained considerable attention due to the fact that these techniques can be easily adapted for standoff detection from considerable distances. The techniques also show high sensitivity and selectivity and offer near real time detection duty cycles. This research focuses in laying the grounds for the spectroscopic differentiation of Staphylococcus spp., Pseudomonas spp., Bacillus spp., Salmonella spp., Enterobacter aerogenes, Proteus mirabilis, Klebsiella pneumoniae, and E. coli, together with identification of their subspecies. In order to achieve the proponed objective, protocols to handle, cultivate and analyze the strains have been developed. Spectroscopic similarities and marked differences have been found for Spontaneous or Normal Raman spectra and for SERS using silver nanoparticles have been found. The use of principal component analysis (PCA), discriminate factor analysis (DFA) and a cluster analysis were used to evaluate the efficacy of identifying potential threat bacterial from their spectra collected on single bacteria. The DFA from the bacteria Raman spectra show a little discrimination between the diverse bacterial species however the results obtained from the SERS demonstrate to be high discrimination technique. The spectroscopic study will be extended to examine the spores produced by selected strains since these are more prone to be used as Biological Warfare Agents due to their increased mobility and possibility of airborne transport. Micro infrared spectroscopy as well as fiber coupled FTIR will also be used as possible sensors of target compounds.

  12. Use of portable microbial samplers for estimating inhalation exposure to viable biological agents.

    Science.gov (United States)

    Yao, Maosheng; Mainelis, Gediminas

    2007-01-01

    Portable microbial samplers are being increasingly used to determine the presence of microbial agents in the air; however, their performance characteristics when sampling airborne biological agents are largely unknown. In addition, it is unknown whether these samplers could be used to assess microbial inhalation exposure according to the particle sampling conventions. This research analyzed collection efficiencies of MAS-100, Microflow, SMA MicroPortable, Millipore Air Tester, SAS Super 180, BioCulture, and RCS High Flow portable microbial samplers when sampling six bacterial and fungal species ranging from 0.61 to 3.14 microm in aerodynamic diameter. The efficiencies with which airborne microorganisms were deposited on samplers' collection medium were compared to the particle inhalation and lung deposition convention curves. When sampling fungi, RCS High Flow and SAS Super 180 deposited 80%-90% of airborne spores on agar - highest among investigated samplers. Other samplers showed collection efficiencies of 10%-60%. When collecting bacteria, RCS High Flow and MAS-100 collected 20%-30%, whereas other samplers collected less than 10% of these bioparticles. Comparison of samplers' collection efficiencies with particle inhalation convention curves showed that RCS High Flow and SAS Super 180 could be used to assess inhalation exposure to particles larger than 2.5 microm, such as fungal spores. Performance of RCS High Flow sampler was also reflective of the particle lung deposition pattern when sampling both bacteria and fungi. MAS-100 and SAS Super 180 matched the total deposition curve fairly well when collecting bacterial and fungi species, respectively. For other tested samplers, we observed substantial discrepancies between their performances and particle deposition efficiencies in the lung. The results show that feasibility of applying portable microbial samplers for exposure assessment depends on a particular sampler model and microbial species.

  13. Optimal Control through Biologically-Inspired Pursuit

    Science.gov (United States)

    2004-01-01

    Transactions on Automatic Control 48, 988– 1001. Roumeliotis, S.I. and G.A. Bekey (2002). Distributed multi-robot localization. IEEE Transactions on Robotics and...1999). Distributed covering by ant- robots using evaporating traces. IEEE Transactions on Robotics and Automation 15(5), 918–933.

  14. Biological effect of penetration controlled irradiation with ion beams

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, Atsushi; Shimizu, Takashi; Kikuchi, Masahiro; Kobayashi, Yasuhiko; Watanabe, Hiroshi [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment; Yamashita, Takao

    1997-03-01

    To investigate the effect of local irradiation with ion beams on biological systems, technique for penetration controlled irradiation has been established. The range in a target was controlled by changing the distance from beam window in the atmosphere, and could be controlled linearly up to about 31 {mu}m in biological material. In addition, the effects of the penetration controlled irradiations with 1.5 MeV/u C and He ions were examined using tobacco pollen. The increased frequency of leaky pollen produced by ion beams suggests that the efficient pollen envelope damages would be induced at the range-end of ion beams. (author)

  15. Flexible Decision Control in an Autonomous Trading Agent

    NARCIS (Netherlands)

    J. Collins (John); W. Ketter (Wolfgang); M. Gini (Maria)

    2007-01-01

    textabstractAn autonomous trading agent is a complex piece of software that must operate in a competitive economic environment and support a research agenda. We describe the structure of decision processes in the MinneTAC trading agent, focusing on the use of evaluators – configurable, composable mo

  16. Autonomous Traffic Control System Using Agent Based Technology

    CERN Document Server

    M, Venkatesh; V, Srinivas

    2011-01-01

    The way of analyzing, designing and building of real-time projects has been changed due to the rapid growth of internet, mobile technologies and intelligent applications. Most of these applications are intelligent, tiny and distributed components called as agent. Agent works like it takes the input from numerous real-time sources and gives back the real-time response. In this paper how these agents can be implemented in vehicle traffic management especially in large cities and identifying various challenges when there is a rapid growth of population and vehicles. In this paper our proposal gives a solution for using autonomous or agent based technology. These autonomous or intelligent agents have the capability to observe, act and learn from their past experience. This system uses the knowledge flow of precedent signal or data to identify the incoming flow of forthcoming signal. Our architecture involves the video analysis and exploration using some Intelligence learning algorithm to estimate and identify the...

  17. Graph-Theoretic Characterizations of Structural Controllability for Multi-Agent System with Switching Topology

    CERN Document Server

    Liu, Xiaomeng; Chen, Ben M

    2012-01-01

    This paper considers the controllability problem for multi-agent systems. In particular, the structural controllability of multi-agent systems under switching topologies is investigated. The structural controllability of multi-agent systems is a generalization of the traditional controllability concept for dynamical systems, and purely based on the communication topologies among agents. The main contributions of the paper are graph-theoretic characterizations of the structural controllability for multi-agent systems. It turns out that the multi-agent system with switching topology is structurally controllable if and only if the union graph G of the underlying communication topologies is connected (single leader) or leader-follower connected (multi-leader). Finally, the paper concludes with several illustrative examples and discussions of the results and future work.

  18. Ambient Agents: Embedded Agents for Remote Control and Monitoring Using the PANGEA Platform

    Science.gov (United States)

    Villarrubia, Gabriel; De Paz, Juan F.; Bajo, Javier; Corchado, Juan M.

    2014-01-01

    Ambient intelligence has advanced significantly during the last few years. The incorporation of image processing and artificial intelligence techniques have opened the possibility for such aspects as pattern recognition, thus allowing for a better adaptation of these systems. This study presents a new model of an embedded agent especially designed to be implemented in sensing devices with resource constraints. This new model of an agent is integrated within the PANGEA (Platform for the Automatic Construction of Organiztions of Intelligent Agents) platform, an organizational-based platform, defining a new sensor role in the system and aimed at providing contextual information and interacting with the environment. A case study was developed over the PANGEA platform and designed using different agents and sensors responsible for providing user support at home in the event of incidents or emergencies. The system presented in the case study incorporates agents in Arduino hardware devices with recognition modules and illuminated bands; it also incorporates IP cameras programmed for automatic tracking, which can connect remotely in the event of emergencies. The user wears a bracelet, which contains a simple vibration sensor that can receive notifications about the emergency situation. PMID:25090416

  19. Ambient agents: embedded agents for remote control and monitoring using the PANGEA platform.

    Science.gov (United States)

    Villarrubia, Gabriel; De Paz, Juan F; Bajo, Javier; Corchado, Juan M

    2014-07-31

    Ambient intelligence has advanced significantly during the last few years. The incorporation of image processing and artificial intelligence techniques have opened the possibility for such aspects as pattern recognition, thus allowing for a better adaptation of these systems. This study presents a new model of an embedded agent especially designed to be implemented in sensing devices with resource constraints. This new model of an agent is integrated within the PANGEA (Platform for the Automatic Construction of Organiztions of Intelligent Agents) platform, an organizational-based platform, defining a new sensor role in the system and aimed at providing contextual information and interacting with the environment. A case study was developed over the PANGEA platform and designed using different agents and sensors responsible for providing user support at home in the event of incidents or emergencies. The system presented in the case study incorporates agents in Arduino hardware devices with recognition modules and illuminated bands; it also incorporates IP cameras programmed for automatic tracking, which can connect remotely in the event of emergencies. The user wears a bracelet, which contains a simple vibration sensor that can receive notifications about the emergency situation.

  20. Terapia com agentes biológicos na criança e no adolescente Treatment with biologic agents in child and adolescent

    Directory of Open Access Journals (Sweden)

    Ricardo Maisse Suehiro

    2010-06-01

    Full Text Available OBJETIVO: Revisar os mecanismos fisiopatológicos e novos alvos terapêuticos, os agentes biológicos disponíveis, principais indicações e a evidência científica atual para o uso de terapias biológicas na população pediátrica. FONTES DE DADOS: Pesquisa na base de dados Medline e SciELO, nas línguas inglesa e portuguesa, entre 2000 e 2009. As palavras-chave usadas foram "agentes biológicos", "crianças" e "adolescentes". SÍNTESE DOS DADOS: Os agentes biológicos são uma importante opção terapêutica para tratar as doenças autoimunes refratárias às terapias convencionais na infância e na adolescência. Com exceção da artrite idiopática juvenil, a maioria dos estudos em outras doenças autoimunes não é controlada. CONCLUSÕES: Os agentes biológicos têm demonstrado eficácia no tratamento de doenças autoimunes pediátricas como artrite idiopática juvenil, miopatias idiopáticas inflamatórias, lúpus eritematoso juvenil, vasculites, uveítes crônicas, doenças inflamatórias intestinais e púrpura trombocitopênica imune crônica, assim como no linfoma não-Hodgkin. Considerando-se o custo elevado e os potenciais eventos adversos, o uso desses agentes deve ser individualizado e acompanhado por especialista.OBJECTIVE: To review the physiopathology and new therapeutical targets, the available biologic agents, the main indications and the current scientific evidence for the use of biological therapies in the pediatric population. DATA SOURCES: A bibliographical search was obtained from Medline and SciELO databases in English and Portuguese from 2000 to 2009. The key-words included were "biologic agent", "children" and "adolescent". DATA SYNTHESIS: Biologic agents are important therapeutic options to treat refractory autoimmune diseases to conventional therapies in childhood and adolescence. Excluding juvenile idiopathic arthritis, the majority of studies in other autoimmune diseases are uncontrolled trials. CONCLUSIONS

  1. Comparison of traditional and molecular analytical methods for detecting biological agents in raw and drinking water following ultrafiltration

    Science.gov (United States)

    Francy, D.S.; Bushon, R.N.; Brady, A.M.G.; Bertke, E.E.; Kephart, C.M.; Likirdopulos, C.A.; Mailot, B.E.; Schaefer, F. W.; Lindquist, H.D. Alan

    2009-01-01

    Aims: To compare the performance of traditional methods to quantitative polymerase chain reaction (qPCR) for detecting five biological agents in large-volume drinking-water samples concentrated by ultrafiltration (UF). Methods and Results: Drinking-water samples (100 l) were seeded with Bacillus anthracis, Cryptospordium parvum, Francisella tularensis, Salmonella Typhi, and Vibrio cholerae and concentrated by UF. Recoveries by traditional methods were variable between samples and between some replicates; recoveries were not determined by qPCR. Francisella tularensis and V. cholerae were detected in all 14 samples after UF, B. anthracis was detected in 13, and C. parvum was detected in 9 out of 14 samples. Numbers found by qPCR after UF were significantly or nearly related to those found by traditional methods for all organisms except for C. parvum. A qPCR assay for S. Typhi was not available. Conclusions: qPCR can be used to rapidly detect biological agents after UF as well as traditional methods, but additional work is needed to improve qPCR assays for several biological agents, determine recoveries by qPCR, and expand the study to other areas. Significance and Impact of the Study: To our knowledge, this is the first study to compare the use of traditional and qPCR methods to detect biological agents in large-volume drinking-water samples. ?? 2009 The Society for Applied Microbiology.

  2. Multiplication of bio-control agents on locally available organic media

    OpenAIRE

    Devakumar, N.; Shubha, S.; Rao, G.G.E.

    2014-01-01

    Multiplication of micro organisms used as bio control agents can be done by using locally available organic materials viz., compost extract, Jeevamrutha, Press mud, digested biogas slurry only. Performance of bio control agents was better with the combination of digested biogas slurry+ Panchagavya; Press mud + Panchagavya and digested biogas slurry + Press mud. Bio-control agents can be multiplied locally with low cost by adding Jaggery solution.

  3. A Loosely Coupled Control Architecture Based on Agent and CORBA for Multiple Robots

    Institute of Scientific and Technical Information of China (English)

    Wu Shandong(吴山东); Chen Yimin; He Yongyi

    2003-01-01

    With the rapid development of information technology, adopting advanced distributed computing technology to construct robot control system is becoming an effective approach gradually. This paper proposes a distributed loosely coupled software architecture based on Agent and CORBA to control multiple robots. This model provides the robot user with agent control units at the semantic level and CORBA provides function interfaces to agent at the syntax level, which shows a good adaptability, flexibility and transparence.

  4. Agent based Particle Swarm Optimization for Load Frequency Control of Distribution Grid

    DEFF Research Database (Denmark)

    Cha, Seung-Tae; Saleem, Arshad; Wu, Qiuwei;

    2012-01-01

    This paper presents a Particle Swarm Optimization (PSO) based on multi-agent controller. Real-time digital simulator (RTDS) is used for modelling the power system, while a PSO based multi-agent LFC algorithm is developed in JAVA for communicating with resource agents and determines the scenario t...

  5. Identification of Biocontrol Agents to Control the Fungal Pathogen, Geomyces destructans, in Bats

    Science.gov (United States)

    Braunstein, S.; Cheng, T.

    2013-12-01

    The fungal pathogen Geomyces destructans (Gd) causes the disease White-nose Syndrome (WNS) in bats and is estimated to have killed millions of bats since its emergence in North America in 2006. Gd is predicted to cause the local extinction of at least three bat species if rates of decline continue unabated. Given the devastating impacts of Gd to bat populations, identifying a viable method for controlling the pathogen is pertinent for conservation of affected bat species. Our work focuses on identifying naturally-occurring skin bacteria on bats that are antagonistic to Gd that could potentially be used as a biocontrol. We cultured bacteria from skin swabs taken from wild bats (Myotis lucifugus, Eptesicus fuscus, Myotis sodalis, Perimyotis subflavus). We conducted challenge experiments to identify bacterial strains that inhibited Gd growth. Bacteria that exhibited antifungal properties were identified using 16S and gyrB markers. Our methods identified several bacteria in the Pseudomonas fluorescens complex as potential biocontrol agents. Future work will continue to test the viability of these bacteria as biocontrol agents via experimental treatments with live captive bats. The failure of previous non-biocontrol methods highlights the importance of developing these bacteria as a biologically-friendly method for controlling Gd. A bat infected with Geomyces destructans. Photo by West Virginia Division of Natural Resources Bacterial culture from the swab of a bat's wings

  6. Capillary zone electrophoresis analysis and detection of mid-spectrum biological warfare agents

    Energy Technology Data Exchange (ETDEWEB)

    Boulet, C.A.; Townsley, C.

    1995-04-01

    DRE Suffield has initiated a research program to develop methods and equipment for field detection and laboratory identification of mid-spectrum agents, molecules of biological origin such as proteins, peptides and toxins. In this study, a highly efficient and reproducible capillary zone electrophoresis method was developed to separate and identify a series of nine peptides of defence interest: bradykinin, bradykinin fragment 1-5, substance P,ARG8-vasopressin, luteinizing hormone releasing hormone, bombesin, leucine enkephalin, methionine enkephalin, and oxytocin. Using a 50 micrometer x 47 cm capillary column, 22.5 kV separation voltage and a 100 mM pH 2.5 phosphate buffer, all nine peptide could separated in under 10 minutes. Three strategies, which could be used in a fully automated field detection and identification system, were demonstrated for the identification of unknown peptides: comparison of migration times, comparison of electrophoretic mobilities, and co-injection of multiple reference standards. These experiments demonstrate that a separation based analytical method such as capillary electrophoresis could form the basis of a generic detection system for mid-spectrum protein and peptide toxins.

  7. Biological evaluation of Phellinus linteus-fermented broths as anti-inflammatory agents.

    Science.gov (United States)

    Lin, Chun-Jung; Lien, Hsiu-Man; Chang, Hsiao-Yun; Huang, Chao-Lu; Liu, Jau-Jin; Chang, Yun-Chieh; Chen, Chia-Chang; Lai, Chih-Ho

    2014-07-01

    Phellinus linteus and its constituent hispolon induce potent anti-inflammatory activity in macrophages. Efficient production of the effective constituent and the biological function of P. linteus in the regulation of innate sensing have rarely been investigated. The aim of this study was to efficiently manufacture P. linteus-fermented broth containing the effective constituent, hispolon, and evaluate its immunoregulatory functions in macrophages. Four distinct fermented broths (PL1-4) and the medium dialyzate (MD) were prepared to screen suitable culture conditions for the mycelial growth of P. linteus. The P. linteus-fermented broth exhibited a dose-responsive inhibition of lipopolysaccharide (LPS)-induced nitric oxide (NO) production by murine macrophages. In addition, the P. linteus-fermented broths suppressed macrophage LPS-mediated nuclear factor (NF)-κB activity and tumor necrosis factor (TNF)-α. Among the tested samples from P. linteus, PL4 contained vast amounts of hispolon and showed the greatest anti-inflammatory activity in both the RAW264.7 cells and murine primary peritoneal exudate macrophages (PEMs). This study demonstrates that the purification of the effective constituent from P. linteus-fermented broth may enable the production of a potent therapeutic agent for anti-inflammation in macrophages.

  8. Modified clay minerals efficiency against chemical and biological warfare agents for civil human protection.

    Science.gov (United States)

    Plachá, Daniela; Rosenbergová, Kateřina; Slabotínský, Jiří; Kutláková, Kateřina Mamulová; Studentová, Soňa; Martynková, Gražyna Simha

    2014-04-30

    Sorption efficiencies of modified montmorillonite and vermiculite of their mono ionic Na and organic HDTMA and HDP forms were studied against chemical and biological warfare agents such as yperite and selected bacterial strains. Yperite interactions with modified clay minerals were observed through its capture in low-density polyethylene foil-modified clay composites by measuring yperite gas permeation with using chemical indication and gas chromatography methods. The antibacterial activities of synthetized organoclays were tested against selected Gram-positive and Gram-negative bacterial species in minimum inhibitory concentration tests. The obtained results showed a positive influence of modified clay minerals on the significant yperite breakthrough-time increase. The most effective material was the polyethylene-Na form montmorillonite, while the polyethylene-Na form vermiculite showed the lowest efficiency. With increasing organic cations loading in the interlayer space the montmorillonite efficiency decreased, and in the case of vermiculite an opposite effect was observed. Generally the modified montmorillonites were more effective than modified vermiculites. The HDP cations seem to be more effective compare to the HDTMA. The antibacterial activity tests confirmed efficiency of all organically modified clay minerals against Gram-positive bacteria. The confirmation of antibacterial activity against Y. pestis, plague bacteria, is the most interesting result of this part of the study.

  9. Conservation biological control of pests in the molecular era: new opportunities to address old constraints

    Directory of Open Access Journals (Sweden)

    Gurr eGeoff

    2016-01-01

    Full Text Available ABSTRACTBiological control has long been considered a potential alternative to pesticidal strategies for pest management but its impact and level of use globally remain modest and inconsistent. A rapidly expanding range of molecular – particularly DNA-related – techniques is currently revolutionizing many life sciences. This review identifies a series of constraints on the development and uptake of conservation biological control and considers the contemporary and likely future influence of molecular methods on these constraints. Molecular approaches are now often used to complement morphological taxonomic methods for the identification and study of biological control agents including microbes. A succession of molecular techniques has been applied to ‘who eats whom’ questions in food-web ecology. Polymerase chain reaction (PCR approaches have largely superseded immunological approaches such as enzyme-linked immunosorbent assay (ELISA and now – in turn – are being overtaken by next generation sequencing (NGS- based approaches that offer unparalleled power at a rapidly diminishing cost. There is scope also to use molecular techniques to manipulate biological control agents, which will be accelerated with the advent of gene editing tools, the CRISPR/Cas9 system in particular. Gene editing tools also offer unparalleled power to both elucidate and manipulate the plant defence mechanisms including those that involve natural enemy attraction to attacked plants. Rapid advances in technology will allow the development of still more novel pest management options for which uptake is likely to be limited chiefly by regulatory hurdles.

  10. Multi-Variable Flocking Control for Multi-Agent Systems via a Received Signal Strength Indicator

    Institute of Scientific and Technical Information of China (English)

    Xin-Ping Guan; Shao-Min Xing; Xiao-Yuan Luo

    2011-01-01

    A novel flocking control approach is proposed for multi-agent systems by integrating the variables of velocities,motion directions,and positions of agents.A received signal strength indicator (RSSI) is applied as a variable to estimate the inter-distance between agents.A key parameter that contains the local information of agents is defined,and a multi-variable controller is proposed based on the parameter.For the position control of agents,the RSSI is introduced to substitute the distance as a control variable in the systems.The advantages of RSSI include that the relative distance between every two agents can be adjusted through the communication quality under different environments,and it can shun the shortage of the limit of sensors.Simulation studies demonstrate the effectiveness of the proposed control approach.

  11. Adaptive Control and Multi-agent Interface for Infotelecommunication Systems of New Generation

    OpenAIRE

    Timofeev, Adil

    2004-01-01

    Problems for intellectualisation for man-machine interface and methods of self-organization for network control in multi-agent infotelecommunication systems have been discussed. Architecture and principles for construction of network and neural agents for telecommunication systems of new generation have been suggested. Methods for adaptive and multi-agent routing for information flows by requests of external agents- users of global telecommunication systems and computer network...

  12. Proceedings First Workshop on Applications of Membrane computing, Concurrency and Agent-based modelling in POPulation biology

    CERN Document Server

    Milazzo, Paolo; 10.4204/EPTCS.33

    2010-01-01

    This volume contains the papers presented at the first International Workshop on Applications of Membrane Computing, Concurrency and Agent-based Modelling in Population Biology (AMCA-POP 2010) held in Jena, Germany on August 25th, 2010 as a satellite event of the 11th Conference on Membrane Computing (CMC11). The aim of the workshop is to investigate whether formal modelling and analysis techniques could be applied with profit to systems of interest for population biology and ecology. The considered modelling notations include membrane systems, Petri nets, agent-based notations, process calculi, automata-based notations, rewriting systems and cellular automata. Such notations enable the application of analysis techniques such as simulation, model checking, abstract interpretation and type systems to study systems of interest in disciplines such as population biology, ecosystem science, epidemiology, genetics, sustainability science, evolution and other disciplines in which population dynamics and interactions...

  13. Exogenous control of biological and ecological systems through evolutionary modelling

    Directory of Open Access Journals (Sweden)

    Alessandro Ferrarini

    2013-09-01

    Full Text Available The controllability of network-like systems is a topical issue in ecology and biology. It relies on the ability to lead a system's behaviour towards the desired state through the appropriate handling of input variables. Up to now, controllability of networks is based on the permanent control of a set of driver nodes that can guide the system's dynamics. This assumption seems motivated by real-world networks observation, where a decentralized control is often applied only to part of the nodes. While in a previous paper I showed that ecological and biological networks can be efficaciously controlled from the inside, here I further introduce a new framework for network controllability based on the employment of exogenous controllers and evolutionary modelling, and provide an exemplification of its application.

  14. Augmentative biological control of arthropods in Latin America

    NARCIS (Netherlands)

    Lenteren, van J.C.; Bueno, V.H.P.

    2003-01-01

    Augmentative forms of biological control, where natural enemies are periodically introduced, are applied over large areas in various cropping systems in Latin America. About 25% of the world area under augmentative control is situated in this region. Well-known examples are the use of species of the

  15. The cactus moth, Cactoblastis cactorum: Lessons in Biological Control

    Science.gov (United States)

    The cactus moth was one of the success stories in classical biological control. In the 1920s, the prickly pear cactus was a serious pest in Australia. The cactus moth was imported from its native habitat in South America and proved so successful in controlling cactus that it was mass reared and exp...

  16. Role of nitrification in the biodegradation of selected artificial sweetening agents in biological wastewater treatment process.

    Science.gov (United States)

    Tran, N H; Nguyen, V T; Urase, T; Ngo, H H

    2014-06-01

    The biodegradation of the six artificial sweetening agents including acesulfame (ACE), aspartame (ASP), cyclamate (CYC), neohesperidindihydrochalcone (NHDC), saccharin (SAC), and sucralose (SUC) by nitrifying activated sludge was first examined. Experimental results showed that ASP and NHDC were the most easily degradable compounds even in the control tests. CYC and SAC were efficiently biodegraded by the nitrifying activated sludge, whereas ACE and SUC were poorly removed. However, the biodegradation efficiencies of the ASs were increased with the increase in initial ammonium concentrations in the bioreactors. The association between nitrification and co-metabolic degradation was investigated and a linear relationship between nitrification rate and co-metabolic biodegradation rate was observed for the target artificial sweeteners (ASs). The contribution of heterotrophic microorganisms and autotrophic ammonia oxidizers in biodegradation of the ASs was elucidated, of which autotrophic ammonia oxidizers played an important role in the biodegradation of the ASs, particularly with regards to ACE and SUC.

  17. Mercury Control with Calcium-Based Sorbents and Oxidizing Agents

    Energy Technology Data Exchange (ETDEWEB)

    Thomas K. Gale

    2005-07-01

    This Final Report contains the test descriptions, results, analysis, correlations, theoretical descriptions, and model derivations produced from many different investigations performed on a project funded by the U.S. Department of Energy, to investigate calcium-based sorbents and injection of oxidizing agents for the removal of mercury. Among the technologies were (a) calcium-based sorbents in general, (b) oxidant-additive sorbents developed originally at the EPA, and (c) optimized calcium/carbon synergism for mercury-removal enhancement. In addition, (d) sodium-tetrasulfide injection was found to effectively capture both forms of mercury across baghouses and ESPs, and has since been demonstrated at a slipstream treating PRB coal. It has been shown that sodium-tetrasulfide had little impact on the foam index of PRB flyash, which may indicate that sodium-tetrasulfide injection could be used at power plants without affecting flyash sales. Another technology, (e) coal blending, was shown to be an effective means of increasing mercury removal, by optimizing the concentration of calcium and carbon in the flyash. In addition to the investigation and validation of multiple mercury-control technologies (a through e above), important fundamental mechanism governing mercury kinetics in flue gas were elucidated. For example, it was shown, for the range of chlorine and unburned-carbon (UBC) concentrations in coal-fired utilities, that chlorine has much less effect on mercury oxidation and removal than UBC in the flyash. Unburned carbon enhances mercury oxidation in the flue gas by reacting with HCl to form chlorinated-carbon sites, which then react with elemental mercury to form mercuric chloride, which subsequently desorbs back into the flue gas. Calcium was found to enhance mercury removal by stabilizing the oxidized mercury formed on carbon surfaces. Finally, a model was developed to describe these mercury adsorption, desorption, oxidation, and removal mechanisms, including

  18. Cell biology. Metabolic control of cell death.

    Science.gov (United States)

    Green, Douglas R; Galluzzi, Lorenzo; Kroemer, Guido

    2014-09-19

    Beyond their contribution to basic metabolism, the major cellular organelles, in particular mitochondria, can determine whether cells respond to stress in an adaptive or suicidal manner. Thus, mitochondria can continuously adapt their shape to changing bioenergetic demands as they are subjected to quality control by autophagy, or they can undergo a lethal permeabilization process that initiates apoptosis. Along similar lines, multiple proteins involved in metabolic circuitries, including oxidative phosphorylation and transport of metabolites across membranes, may participate in the regulated or catastrophic dismantling of organelles. Many factors that were initially characterized as cell death regulators are now known to physically or functionally interact with metabolic enzymes. Thus, several metabolic cues regulate the propensity of cells to activate self-destructive programs, in part by acting on nutrient sensors. This suggests the existence of "metabolic checkpoints" that dictate cell fate in response to metabolic fluctuations. Here, we discuss recent insights into the intersection between metabolism and cell death regulation that have major implications for the comprehension and manipulation of unwarranted cell loss.

  19. Design, synthesis and biological evaluation of novel benzimidazole-2-substituted phenyl or pyridine propyl ketene derivatives as antitumour agents.

    Science.gov (United States)

    Wu, Lin-tao; Jiang, Zhi; Shen, Jia-jia; Yi, Hong; Zhan, Yue-chen; Sha, Ming-quan; Wang, Zhen; Xue, Si-tu; Li, Zhuo-rong

    2016-05-23

    A series of novel benzimidazole-2-subsituted phenyl or pyridine propyl ketene derivatives were designed and synthesized. The biological activities of these derivatives were then evaluated as potential antitumour agents. These compounds were assayed for growth-inhibitory activity against HCT116, MCF-7 and HepG2 cell lines in vitro. The IC50 values of compounds A1 and A7 against the cancer cells were 0.06-3.64 μM and 0.04-9.80 μM, respectively. Their antiproliferative activities were significantly better than that of 5-Fluorouracil (IC50: 56.96-174.50 μM) and were close to that of Paclitaxel (IC50: 0.026-1.53 μM). The activity of these derivatives was over 100 times more effective than other reported structures of chalcone analogues (licochalcone A). A preliminary mechanistic study suggested that these compounds inhibit p53-MDM2 binding. Compounds A1, A7 and A9 effectively inhibited tumour growth in BALB/c mice with colon carcinoma HCT116 cells. The group administered 200 mg/kg of compound A7 showed a 74.6% tumour growth inhibition with no signs of toxicity at high doses that was similar to the inhibition achieved with the 12.5 mg/kg irinotecan positive control (70.2%). Therefore, this class of benzimidazole-2-subsituted phenyl or pyridine propyl ketene derivatives represents a promising lead structure for the development of possible p53-MDM2 inhibitors as new antitumour agents.

  20. Biological control of invasive plant species: a reassessment for the Anthropocene.

    Science.gov (United States)

    Seastedt, Timothy R

    2015-01-01

    The science of finding, testing and releasing herbivores and pathogens to control invasive plant species has achieved a level of maturity and success that argues for continued and expanded use of this program. The practice, however, remains unpopular with some conservationists, invasion biologists, and stakeholders. The ecological and economic benefits of controlling densities of problematic plant species using biological control agents can be quantified, but the risks and net benefits of biological control programs are often derived from social or cultural rather than scientific criteria. Management of invasive plants is a 'wicked problem', and local outcomes to wicked problems have both positive and negative consequences differentially affecting various groups of stakeholders. The program has inherent uncertainties; inserting species into communities that are experiencing directional or even transformational changes can produce multiple outcomes due to context-specific factors that are further confounded by environmental change drivers. Despite these uncertainties, biological control could play a larger role in mitigation and adaptation strategies used to maintain biological diversity as well as contribute to human well-being by protecting food and fiber resources.

  1. Implementation of integral feedback control in biological systems.

    Science.gov (United States)

    Somvanshi, Pramod R; Patel, Anilkumar K; Bhartiya, Sharad; Venkatesh, K V

    2015-01-01

    Integral control design ensures that a key variable in a system is tightly maintained within acceptable levels. This approach has been widely used in engineering systems to ensure offset free operation in the presence of perturbations. Several biological systems employ such an integral control design to regulate cellular processes. An integral control design motif requires a negative feedback and an integrating process in the network loop. This review describes several biological systems, ranging from bacteria to higher organisms in which the presence of integral control principle has been hypothesized. The review highlights that in addition to the negative feedback, occurrence of zero-order kinetics in the process is a key element to realize the integral control strategy. Although the integral control motif is common to these systems, the mechanisms involved in achieving it are highly specific and can be incorporated at the level of signaling, metabolism, or at the phenotypic levels.

  2. Cooperative control of multi-agent systems optimal and adaptive design approaches

    CERN Document Server

    Lewis, Frank L; Hengster-Movric, Kristian; Das, Abhijit

    2014-01-01

    Task complexity, communication constraints, flexibility and energy-saving concerns are all factors that may require a group of autonomous agents to work together in a cooperative manner. Applications involving such complications include mobile robots, wireless sensor networks, unmanned aerial vehicles (UAVs), spacecraft, and so on. In such networked multi-agent scenarios, the restrictions imposed by the communication graph topology can pose severe problems in the design of cooperative feedback control systems.  Cooperative control of multi-agent systems is a challenging topic for both control theorists and practitioners and has been the subject of significant recent research. Cooperative Control of Multi-Agent Systems extends optimal control and adaptive control design methods to multi-agent systems on communication graphs.  It develops Riccati design techniques for general linear dynamics for cooperative state feedback design, cooperative observer design, and cooperative dynamic output feedback design.  B...

  3. Citrus growers vary in their adoption of biological control

    OpenAIRE

    Grogan, Kelly A.; Goodhue, Rachael E.

    2012-01-01

    In a spring 2010 survey, we investigated the characteristics that influenced whether California growers controlled major citrus pests with beneficial insects. We also performed statistical analysis of growers' reliance on Aphytus melinus, a predatory wasp, to control California red scale. The survey results suggest that growers with greater citrus acreage and more education are more likely to use biological control. Marketing outlets, ethnicity and primary information sources also influenced ...

  4. Biologic agents for the treatment of juvenile rheumatoid arthritis: current status.

    Science.gov (United States)

    Carrasco, Ruy; Smith, Judith A; Lovell, Daniel

    2004-01-01

    Biologic therapies, primarily anticytokine therapies, are being increasingly used in patients with juvenile rheumatoid arthritis (JRA). Levels of a variety of proinflammatory cytokines have been shown to be elevated in the peripheral blood and synovial fluid and tissue in children with JRA. In a blinded, randomized, controlled trial in children with severe, long-standing, polyarticular-course JRA not responsive to standard therapies, etanercept showed a statistically significantly greater response rate than placebo. Approximately 75% of these children responded to etanercept. Etanercept has been efficacious in 50-60% of children with active systemic JRA in open clinical trials with acceptable tolerance. Adverse events seen in children treated with etanercept have been similar in type and frequency to those reported in adults. Infliximab has been studied in several open clinical trials in both polyarticular and systemic JRA and found to, overall, have demonstrated efficacy in approximately 60% of patients. Approximately 3-5% of patients have demonstrated infusion reactions or frank allergic reactions and 9% developed new autoantibodies. Anakinra has been studied in children with polyarticular JRA. Approximately 65% of patients developed injection-site reactions and 68% demonstrated a response to the medication. Anakinra may have increased efficacy in systemic JRA. Interleukin (IL)-6 is highly related to the systemic disease manifestations in systemic JRA and two patients treated with a monoclonal antibody to the IL-6 receptor have demonstrated significant improvement with prolonged clinical control with continued treatment. A particular pediatric concern is the effect of immunosuppressive biologics in children who are exposed to or develop varicella. These children should be treated, both in terms of prophylaxis and aggressive antivaricella treatment, as for other immunosuppressed children. Anticytokine biologics have demonstrated great promise in the treatment of

  5. An estimate of the cost of administering intravenous biological agents in Spanish day hospitals

    Science.gov (United States)

    Nolla, Joan Miquel; Martín, Esperanza; Llamas, Pilar; Manero, Javier; Rodríguez de la Serna, Arturo; Fernández-Miera, Manuel Francisco; Rodríguez, Mercedes; López, José Manuel; Ivanova, Alexandra; Aragón, Belén

    2017-01-01

    Objective To estimate the unit costs of administering intravenous (IV) biological agents in day hospitals (DHs) in the Spanish National Health System. Patients and methods Data were obtained from 188 patients with rheumatoid arthritis, collected from nine DHs, receiving one of the following IV therapies: infliximab (n=48), rituximab (n=38), abatacept (n=41), or tocilizumab (n=61). The fieldwork was carried out between March 2013 and March 2014. The following three groups of costs were considered: 1) structural costs, 2) material costs, and 3) staff costs. Staff costs were considered a fixed cost and were estimated according to the DH theoretical level of activity, which includes, as well as personal care of each patient, the DH general activities (complete imputation method, CIM). In addition, an alternative calculation was performed, in which the staff costs were considered a variable cost imputed according to the time spent on direct care (partial imputation method, PIM). All costs were expressed in euros for the reference year 2014. Results The average total cost was €146.12 per infusion (standard deviation [SD] ±87.11; CIM) and €29.70 per infusion (SD ±11.42; PIM). The structure-related costs per infusion varied between €2.23 and €62.35 per patient and DH; the cost of consumables oscillated between €3.48 and €20.34 per patient and DH. In terms of the care process, the average difference between the shortest and the longest time taken by different hospitals to administer an IV biological therapy was 113 minutes. Conclusion The average total cost of infusion was less than that normally used in models of economic evaluation coming from secondary sources. This cost is even less when the staff costs are imputed according to the PIM. A high degree of variability was observed between different DHs in the cost of the consumables, in the structure-related costs, and in those of the care process. PMID:28356746

  6. The role of biological agents in the management of large vessel vasculitis (LVV: a systematic review and meta-analysis.

    Directory of Open Access Journals (Sweden)

    Mohammed Osman

    Full Text Available BACKGROUND: Giant cell arteritis (GCA and Takayasu's arteritis (TAA are large vessel vasculitides (LVV for which corticosteroids (CS are the mainstay for treatment. In patients with LVV unable to tolerate CS, biological agents have been used with variable effectiveness. OBJECTIVE: To systematically review the effectiveness and safety of biological agents in patients with LVV. METHODS: We searched 5 electronic databases (inception to October 2012 and conference abstracts with no language restrictions. Two reviewers independently selected studies, extracted data and assessed methodological quality. Our protocol was registered in PROSPERO. RESULTS: We included 25 studies (3 RCTs and 22 case series with ≥2 cases. 95 GCA and 98 TAA patients received biological agents. The RCTs using anti-TNF agents (infliximab, etanercept and adalimumab did not suggest a benefit in GCA. GCA patients receiving tocilizumab, in case series, achieved remission (19 patients and reduction of corticosteroid dose (mean difference, -16.55 mg/day (95% CI: -26.24, -6.86. In case series, 75 patients with refractory TAA treated with infliximab discontinued CS 32% of the time. Remission was variably defined and the studies were clinically heterogeneous which precluded further analysis. CONCLUSION: This systematic review demonstrated a weak evidence base on which to assess the effectiveness of biological treatment in LVV. Evidence from RCTs suggests that anti-TNF agents are not effective for remission or reduction of CS use. Tocilizumab and infliximab may be effective in the management of LVV and refractory TAA, respectively, although the evidence comes from case series. Future analytical studies are needed to confirm these findings.

  7. Reducing Mortality from Terrorist Releases of Chemical and Biological Agents: I. Filtration for Ventilation Systems in Commercial Building

    Energy Technology Data Exchange (ETDEWEB)

    Thatcher, Tracy L.; Daisey, Joan M.

    1999-09-01

    There is growing concern about potential terrorist attacks involving releases of chemical and/or biological (CB) agents, such as sarin or anthrax, in and around buildings. For an external release, the CB agent can enter the building through the air intakes of a building's mechanical ventilation system and by infiltration through the building envelope. For an interior release in a single room, the mechanical ventilation system, which often recirculates some fraction of the air within a building, may distribute the released CB agent throughout the building. For both cases, installing building systems that remove chemical and biological agents may be the most effective way to protect building occupants. Filtration systems installed in the heating, ventilating and air-conditioning (HVAC) systems of buildings can significantly reduce exposures of building occupants in the event of a release, whether the release is outdoors or indoors. Reduced exposures can reduce the number of deaths from a terrorist attack. The purpose of this report is to provide information and examples of the design of filtration systems to help building engineers retrofit HVAC systems. The report also provides background information on the physical nature of CB agents and brief overviews of the basic principles of particle and vapor filtration.

  8. Biophysically realistic filament bending dynamics in agent-based biological simulation.

    Science.gov (United States)

    Alberts, Jonathan B

    2009-01-01

    An appealing tool for study of the complex biological behaviors that can emerge from networks of simple molecular interactions is an agent-based, computational simulation that explicitly tracks small-scale local interactions--following thousands to millions of states through time. For many critical cell processes (e.g. cytokinetic furrow specification, nuclear centration, cytokinesis), the flexible nature of cytoskeletal filaments is likely to be critical. Any computer model that hopes to explain the complex emergent behaviors in these processes therefore needs to encode filament flexibility in a realistic manner. Here I present a numerically convenient and biophysically realistic method for modeling cytoskeletal filament flexibility in silico. Each cytoskeletal filament is represented by a series of rigid segments linked end-to-end in series with a variable attachment point for the translational elastic element. This connection scheme allows an empirically tuning, for a wide range of segment sizes, viscosities, and time-steps, that endows any filament species with the experimentally observed (or theoretically expected) static force deflection, relaxation time-constant, and thermal writhing motions. I additionally employ a unique pair of elastic elements--one representing the axial and the other the bending rigidity- that formulate the restoring force in terms of single time-step constraint resolution. This method is highly local -adjacent rigid segments of a filament only interact with one another through constraint forces-and is thus well-suited to simulations in which arbitrary additional forces (e.g. those representing interactions of a filament with other bodies or cross-links / entanglements between filaments) may be present. Implementation in code is straightforward; Java source code is available at www.celldynamics.org.

  9. Biophysically realistic filament bending dynamics in agent-based biological simulation.

    Directory of Open Access Journals (Sweden)

    Jonathan B Alberts

    Full Text Available An appealing tool for study of the complex biological behaviors that can emerge from networks of simple molecular interactions is an agent-based, computational simulation that explicitly tracks small-scale local interactions--following thousands to millions of states through time. For many critical cell processes (e.g. cytokinetic furrow specification, nuclear centration, cytokinesis, the flexible nature of cytoskeletal filaments is likely to be critical. Any computer model that hopes to explain the complex emergent behaviors in these processes therefore needs to encode filament flexibility in a realistic manner. Here I present a numerically convenient and biophysically realistic method for modeling cytoskeletal filament flexibility in silico. Each cytoskeletal filament is represented by a series of rigid segments linked end-to-end in series with a variable attachment point for the translational elastic element. This connection scheme allows an empirically tuning, for a wide range of segment sizes, viscosities, and time-steps, that endows any filament species with the experimentally observed (or theoretically expected static force deflection, relaxation time-constant, and thermal writhing motions. I additionally employ a unique pair of elastic elements--one representing the axial and the other the bending rigidity- that formulate the restoring force in terms of single time-step constraint resolution. This method is highly local -adjacent rigid segments of a filament only interact with one another through constraint forces-and is thus well-suited to simulations in which arbitrary additional forces (e.g. those representing interactions of a filament with other bodies or cross-links / entanglements between filaments may be present. Implementation in code is straightforward; Java source code is available at www.celldynamics.org.

  10. Preliminary assessment of the interaction of introduced biological agents with biofilms in water distribution systems.

    Energy Technology Data Exchange (ETDEWEB)

    Sinclair, Michael B.; Caldwell, Sara; Jones, Howland D. T.; Altman, Susan Jeanne; Souza, Caroline Ann; McGrath, Lucas K.

    2005-12-01

    Basic research is needed to better understand the potential risk of dangerous biological agents that are unintentionally or intentionally introduced into a water distribution system. We report on our capabilities to conduct such studies and our preliminary investigations. In 2004, the Biofilms Laboratory was initiated for the purpose of conducting applied research related to biofilms with a focus on application, application testing and system-scale research. Capabilities within the laboratory are the ability to grow biofilms formed from known bacteria or biofilms from drinking water. Biofilms can be grown quickly in drip-flow reactors or under conditions more analogous to drinking-water distribution systems in annular reactors. Biofilms can be assessed through standard microbiological techniques (i .e, aerobic plate counts) or with various visualization techniques including epifluorescent and confocal laser scanning microscopy and confocal fluorescence hyperspectral imaging with multivariate analysis. We have demonstrated the ability to grow reproducible Pseudomonas fluorescens biofilms in the annular reactor with plate counts on the order of 10{sup 5} and 10{sup 6} CFU/cm{sup 2}. Stationary phase growth is typically reached 5 to 10 days after inoculation. We have also conducted a series of pathogen-introduction experiments, where we have observed that both polystyrene microspheres and Bacillus cereus (as a surrogate for B. anthracis) stay incorporated in the biofilms for the duration of our experiments, which lasted as long as 36 days. These results indicated that biofilms may act as a safe harbor for bio-pathogens in drinking water systems, making it difficult to decontaminate the systems.

  11. Surface plasmon resonance detection of biological warfare agent Staphylococcal enterotoxin B using high affinity monoclonal antibody

    Energy Technology Data Exchange (ETDEWEB)

    Gupta, Garima; Singh, Pawan K.; Boopathi, M., E-mail: mannanboopathi@yahoo.com; Kamboj, D.V.; Singh, Beer; Vijayaraghavan, R.

    2010-11-30

    A novel sensitive method was developed for the detection as well as quantification of Staphylococcal enterotoxin B (SEB) using surface plasmon resonance (SPR). It is well known that the amount of SEB needed to cause the intoxication to human beings is very less and this concentration (0.02 {mu}g/kg) is highly dangerous, hence, it is used as biological warfare agent. Thus, the need to develop a reliable and potential detection system against SEB is warranted. In the present work, SEB antibody was immobilized on carboxymethyldextran modified gold chip. The immobilization of SEB antibody and interaction of antigen with immobilized antibody were in-situ characterized by SPR and electrochemical impedance spectroscopy. A sample solution containing SEB antigen was injected in a working channel and the results revealed linearity in the concentration from 2.0 to 32.0 pM with a detection limit of 1.0 pM. By using kinetic evaluation software, K{sub D} (equilibrium constant) and Bmax (maximum binding capacity of analyte) values were calculated and found to be 13 pM and 424.23, respectively. Moreover, the thermodynamic parameter, change in Gibb's free energy was deduced and found to be -62.08 kJ/mol and this value shows the spontaneous interaction between SEB antigen and SEB antibody. In order to optimize the detection method, temperature and pH variation studies were also performed. Interference study was conducted to know the selectivity for the antigen-antibody interaction of SEB. The selectivity efficiency of SEB, SEC, SEA and SED were 100, 27.15, 20.01 and 12.05%, respectively towards SEB antibody.

  12. ADVANCED MOLECULAR DESIGN OF BIOPOLYMERS FOR TRANSMUCOSAL AND INTRACELLULAR DELIVERY OF CHEMOTHERAPEUTIC AGENTS AND BIOLOGICAL THERAPEUTICS

    Science.gov (United States)

    Liechty, William B.; Caldorera-Moore, Mary; Phillips, Margaret A.; Schoener, Cody; Peppas, Nicholas A.

    2011-01-01

    Hydrogels have been instrumental in the development of polymeric systems for controlled release of therapeutic agents. These materials are attractive for transmucosal and intracellular drug delivery because of their facile synthesis, inherent biocompatibility, tunable physicochemical properties, and capacity to respond to various physiological stimuli. In this contribution, we outline a multifaceted hydrogel-based approach for expanding the range of therapeutics in oral formulations from classical small-molecule drugs to include proteins, chemotherapeutics, and nucleic acids. Through judicious materials selection and careful design of copolymer composition and molecular architecture, we can engineer systems capable of responding to distinct physiological cues, with tunable physicochemical properties that are optimized to load, protect, and deliver valuable macromolecular payloads to their intended site of action. These hydrogel carriers, including complexation hydrogels, tethered hydrogels, interpenetrating networks, nanoscale hydrogels, and hydrogels with decorated structures are investigated for their ability respond to changes in pH, to load and release insulin and fluorescein, and remain non-toxic to Caco-2 cells. Our results suggest these novel hydrogel networks have great potential for controlled delivery of proteins, chemotherapeutics, and nucleic acids. PMID:21699934

  13. Low-level Control of Network Elements from an Agent Platform

    DEFF Research Database (Denmark)

    Hansen, Mads Stenhuus; Jensen, P.; Soldatos, J.;

    1999-01-01

    An important issue for the implementation of an agent system, which controls a telecommunications network, is to enable low-level access of the network devices by the agent platform, bypassing the control logic inherent in them. This issue has been coped with successfully in the IMPACT project...

  14. Comparison of long-term drug survival and safety of biologic agents in patients with psoriasis vulgaris

    DEFF Research Database (Denmark)

    Gniadecki, R; Bang, B; Bryld, L E

    2015-01-01

    a significantly longer drug survival than the anti-TNF-α agents. Switching from one biologic to another is associated with an impairment of drug survival. Preventing loss of efficacy is a major area of medical need in the biologic therapy of psoriasis and the strategies that improve drug survival should......BACKGROUND: Drug survival (time to drug discontinuation) has recently emerged as an important parameter reflecting the long-term therapeutic performance in a real-life setting. Biologic drug survival in psoriasis is mainly limited by a gradual loss of efficacy over time. Previous studies have been...... limited by small patient population size and short observation times and yielded discrepant survival times for different biologics. OBJECTIVES: To calculate the long-term drug survival for adalimumab, etanercept, infliximab and ustekinumab in a large cohort of real-life patients with psoriasis vulgaris...

  15. Reference model based consensus control of second-order multi-agent systems

    Institute of Scientific and Technical Information of China (English)

    Li Jian-Zhen

    2011-01-01

    This paper deals with the consensus problem of multi-agent systems with second-order dynamics. The objective is to design algorithms such that all agents will have same positions and velocities. First, a reference model based consensus algorithm is proposed. It is proved that the consensus can be achieved if the communication graph has a spanning tree. Different from most of the consensus algorithms proposed in the literature, the parameters of the control laws are different among agents. Therefore, each agent can design its control law independently. Secondly, it gives a consensus algorithm for the case that the velocities of the agents are not available. Thirdly, the effectiveness of the input delay and the communication delay is considered. It shows that consensus can be achieved if the input delay of every agent is smaller than a bound related to parameters in its control law. Finally, some numerical examples are given to illustrate the proposed results.

  16. Biological Control beneath the Feet: A Review of Crop Protection against Insect Root Herbivores

    Directory of Open Access Journals (Sweden)

    Alan Kergunteuil

    2016-11-01

    Full Text Available Sustainable agriculture is certainly one of the most important challenges at present, considering both human population demography and evidence showing that crop productivity based on chemical control is plateauing. While the environmental and health threats of conventional agriculture are increasing, ecological research is offering promising solutions for crop protection against herbivore pests. While most research has focused on aboveground systems, several major crop pests are uniquely feeding on roots. We here aim at documenting the current and potential use of several biological control agents, including micro-organisms (viruses, bacteria, fungi, and nematodes and invertebrates included among the macrofauna of soils (arthropods and annelids that are used against root herbivores. In addition, we discuss the synergistic action of different bio-control agents when co-inoculated in soil and how the induction and priming of plant chemical defense could be synergized with the use of the bio-control agents described above to optimize root pest control. Finally, we highlight the gaps in the research for optimizing a more sustainable management of root pests.

  17. An Agent-based Extensible Climate Control System for Sustainable Greenhouse Production

    DEFF Research Database (Denmark)

    Sørensen, Jan Corfixen; Jørgensen, Bo Nørregaard; Klein, Mark

    2011-01-01

    The slow adoption pace of new control strategies for sustainable greenhouse climate control by industrial growers is mainly due to the complexity of identifying and resolving potentially conflicting climate control requirements. In this paper, we present a multi-agent-based climate control system...... that allows new requirements to be added without any need to identify or resolve conflicts beforehand. This is achieved by representing the climate control requirements as separate agents. Identifying and solving conflicts now become a negotiation problem among agents sharing the same controlled environment....... Negotiation is done using a novel multi-issue negotiation protocol that uses a generic algorithm to find an optimized solution within the search space. The Multi-Agent control system has been empirically evaluated in an ornamental floriculture research facility in Denmark. The evaluation showed...

  18. Hierarchical Distributed Control Design for Multi-agent Systems Using Approximate Simulation

    Institute of Scientific and Technical Information of China (English)

    TANG Yu-Tao; HONG Yi-Guang

    2013-01-01

    In this paper,we consider a hierarchical control design for multi-agent systems based on approximate simulation.To reduce complexity,we first construct a simple abstract system to guide the agents,then we discuss the simulation relations between the abstract system and multiple agents.With the help of this abstract system,distributed hierarchical control is proposed to complete a coordination task.By virtue of a common Lyapunov function,we analyze the collective behaviors with switching multi-agent topology in light of simulation functions.

  19. Chemical composition and biological evaluation of Physalis peruviana root as hepato-renal protective agent.

    Science.gov (United States)

    El-Gengaihi, Souad E; Hassan, Emad E; Hamed, Manal A; Zahran, Hanan G; Mohammed, Mona A

    2013-03-01

    This study was designed to investigate the potential of Physalis peruviana root as a functional food with hepato-renal protective effects against fibrosis. The chemical composition of the plant root suggested the presence of alkaloids, withanolides and flavonoids. Five compounds were isolated and their structures elucidated by different spectral analysis techniques. One compound was isolated from the roots: cuscohygrine. The biological evaluation was conducted on different animal groups; control rats, control treated with ethanolic root extract, CCl(4) group, CCl(4) treated with root extract, and CCl(4) treated with silymarin as a standard herbal drug. The evaluation used the oxidative stress markers malondialdehyde (MDA), superoxide dismutase (SOD), and nitric oxide (NO). The liver function indices; aspartate and alanine aminotransferases (AST & ALT), alkaline phosphatase (ALP), gamma glutamyl transferase (GGT), bilirubin, and total hepatic protein were also estimated. Kidney disorder biomarkers; creatinine, urea, and serum protein were also evaluated. The results suggested safe administration, and improvement of all the investigated parameters. The liver and kidney histopathological analysis confirmed the results. In conclusion, P. peruviana succeeded in protecting the liver and kidney against fibrosis. Further studies are needed to discern their pharmacological applications and clinical uses.

  20. Perspectives on the potential of entomopathogenic fungi in biological control of ticks.

    Science.gov (United States)

    Fernandes, Éverton K K; Bittencourt, Vânia R E P; Roberts, Donald W

    2012-03-01

    Ticks are serious health threats for humans, and both domestic and wild animals. Ticks are controlled mostly by application of chemical products; but these acaricides have several negative side effects, including toxicity to animals, environmental contamination, and induction of chemical resistance in some tick populations. Entomopathogenic fungi infect arthropods in nature and can occur at enzootic or epizootic levels in their host populations. Laboratory studies clearly demonstrate that these fungi can cause high mortality in all developmental stages of several tick species, and also reduce oviposition of infected engorged females. Tick mortality following application of fungi in the field, however, often is less than that suggested by laboratory tests. This is due to many negative biotic and climatic factors. To increase efficacy of fungal agents for biological control of ticks under natural conditions, several points need consideration: (1) select effective isolates (viz., high virulence; and tolerance to high temperature, ultraviolet radiation and desiccation); (2) understand the main factors that affect virulence of fungal isolates to their target arthropods including the role of toxic metabolites of the fungal isolates; and (3) define with more precision the immune response of ticks to infection by entomopathogenic fungi. The current study reviews recent literature on biological control of ticks, and comments on the relevance of these results to advancing the development of fungal biocontrol agents, including improving formulation of fungal spores for use in tick control, and using entomopathogenic fungi in integrated pest (tick) management programs.

  1. Serum anticyclic citrullinated protein antibody titers are correlated with the response to biological agents in patients with rheumatoid arthritis

    Directory of Open Access Journals (Sweden)

    Takahashi R

    2014-05-01

    Full Text Available Ryo Takahashi, Sakiko Isojima, Masayu Umemura, Yoko Miura, Nao Oguro, Syo Ishii, Shinya Seki, Takahiro Tokunaga, Hiroyuki Tsukamoto, Hidekazu Furuya, Ryo Yanai, Tsuyoshi KasamaDivision of Rheumatology, Department of Medicine, Showa University School of Medicine,Tokyo, Japan Abstract: Anticyclic citrullinated protein antibody (ACPA is known as an important indicator for diagnosis of rheumatoid arthritis (RA. Our aim was to examine the relationship between the serum ACPA titer at baseline and responsiveness to biological agents (antagonists of either tumor necrosis factor or interleukin 6 in patients with RA. ACPA was measured using second-generation chemiluminescent enzyme immunoassay. Disease activity was assessed using disease activity scores 28. Fifty-seven RA patients with biological agents were enrolled, and the median ACPA titer at baseline was 110.0 U/mL. The median ACPA titer was 23.3 U/mL and 183.0 U/mL in the good and moderate response groups, respectively, which were significantly lower than in the no response group (404.0 U/mL. In addition, 69.2% and 26.9% of patients with low (<100 U/mL and moderate (100–499 U/mL basal ACPA titers showed a moderate to good response. Of the patients with higher (≥500 U/mL basal ACPA titers, only 14.0% and 42.5% showed a good or moderate response, respectively. The remission rate was 77.8% in the ACPA-negative, which was significantly higher than the rate of 25% in the ACPA-positive patients. The results suggest that the ACPA titers are correlated with the efficacy of the biological agents used in patients with RA.Keywords: biological agents, remission

  2. Methylene Diphosphonate Chemical and Biological control of MDP complex

    CERN Document Server

    Aungurarat, A

    2000-01-01

    Technetium-9 sup 9 sup m MDP easy prepared from MDP kits which different sources such as OAP (In house), SIGMA. The resulting Tc 9 sup 9 sup m -MDP preparations were controlled in chemical and biological tests to compare the different results in these cases: radiochemical purity, the quantity of starting material and biodistribution result.

  3. Conditional lethality strains for the biological control of Anastrepha species

    Science.gov (United States)

    Pro-apoptotic cell death genes are promising candidates for biologically-based autocidal control of pest insects as demonstrated by tetracycline (tet)-suppressible systems for conditional embryonic lethality in Drosophila melanogaster (Dm) and the medfly, Ceratitis capitata (Cc). However, for medfly...

  4. Integrating Biological Systems in the Process Dynamics and Control Curriculum

    Science.gov (United States)

    Parker, Robert S.; Doyle, Francis J.; Henson, Michael A.

    2006-01-01

    The evolution of the chemical engineering discipline motivates a re-evaluation of the process dynamics and control curriculum. A key requirement of future courses will be the introduction of theoretical concepts and application examples relevant to emerging areas, notably complex biological systems. We outline the critical concepts required to…

  5. Biologically formed calcium carbonate : a durable plugging agent for enhanced oil recovery

    Energy Technology Data Exchange (ETDEWEB)

    Nemati, M.; Voordouw, G. [Calgary Univ., AB (Canada)

    2002-06-01

    Waterflooding is a common enhanced oil recovery method in which water is injected into an oil reservoir. The flow is diverted into high permeability zones from which oil has already been recovered during primary production. The increased permeability variation decreases volumetric sweep efficiency of injected water. Cross flow complicates this problem by allowing flow between contrasting layers. This results in a ratio of produced water to oil that is much too high. The use of calcium carbonate (CaCO{sub 3}) and silica may be an effective method for selective plugging of reservoirs. The controlled biological formation of CaCO{sub 3} depends on the decomposition of urea to carbonate and ammonium ions by the catalytic action of urease enzyme. This study shows that biological formation of CaCO{sub 3} could be induced successfully using a bacterium with urease producing activity or urease enzyme. It is shown that the yield of enzymatically produced CaCO{sub 3} is substantially higher than when bacterially produced because the tolerable level of urea for bacteria is lower than the concentration of urea that participates in the enzymatic reaction. Plugging studies in unconsolidated porous media have shown that in situ formation of CaCO{sub 3} may decrease the permeability of porous media. The extent of plugging depends on the enzyme and reactant concentration. The extent of enzymatically produced CaCO{sub 3} increases with higher enzyme concentrations as well as with higher temperature. In situ formation of CaCO{sub 3} could result in a major decrease in permeability. 4 refs., 1 tab., 1 fig.

  6. Construction of biological control strain of Trichoderma viride and study of their ability to induce plant disease resistance

    Institute of Scientific and Technical Information of China (English)

    LIU Shi-wang; GUO Ze-jian

    2004-01-01

    @@ Plant diseases heavily affct plant growth and crop yield even in modern agriculture. Control its difficult because pathogens mutate frequently, and this leads in frequent breaking of disease resistance in commercial cultivars. The excessive application of chemical pesticides is not only producing pesticideresistant pathogens, but it is harming the environment threatening the health of human beings.Therefore, the use of biological control agents (BCA) may provide an environmental friendly alternative to chemicals for plant disease control. Hypersensitive response (HR) and systemic acquired resistance (SAR) are the typical expressions of plant defense reactions. Once SAR is established,, the plants exhibits a broad-spectrum of disease resistance against pathogen attack. Researchers have identified elicitor proteins, such as elicitins and harpins, which activate plant defense reactions. It would be useful to explore the possibility of using biological control agents to induce a status of SAR in crop plants.

  7. Evaluation of Beauveria bassiana (Hyphomycetes) isolates as potential agents for control of Dendroctonus valens

    Institute of Scientific and Technical Information of China (English)

    Long-Wa Zhang; Yu-Jun Liu; Jian Yao; Bin Wang; Bo Huang; Zeng-Zhi Li; Mei-Zhen Fan; Jiang-Hua Sun

    2011-01-01

    The red turpentine beetle (RTB), Dendroctonus valens LeConte, as a destructive invasive pest, has become one of the most economically important forest pest in China. Effective control measures are desperately needed. Entomopathogenic fungi, such as Beauveria bassiana, have shown great potential for the management of some bark beetle species. In this study, 12 isolates of B. bassiana from bark beetle were examined for biological characteristics and virulence, to assess their potential as biocontrol agents for RTB. There were significant differences (at P = 0.05) in colony growth rate, conidial yield, conidial germination, tolerance to UV light and extracellular proteases activity among the tested B. bassiana isolates. Isolates, including Bbl801, Bbl906, Bb789 and Bb773, exhibited the best characteristics, because they have faster hyphal growth rate, higher spore production and faster spore germination, higher UV tolerance and protease (Prl) production. The results of a pathogenicity test of B. bassiana on RTB larvae showed that most isolates of B. bassiana have demonstrated high efficacy and the highest virulent isolate was Bbl801, which killed 100% of the treated insects and had a median lethal time (LT50) of 4.60 days at a concentration of 1× 107 conidia/mL. Therefore, isolate Bb 1801 has a great potential for sustainable control of RTB in the forest. The correlation between biological characteristics and virulence of the fungal isolates is discussed and the possibility of combination of entomopathogenic fungi with semiochemicals, as one of the promising strategy for RTB control, is considered.

  8. Economic Benefit for Cuban Laurel Thrips Biological Control.

    Science.gov (United States)

    Shogren, C; Paine, T D

    2016-02-01

    The Cuban laurel thrips, Gynaikothrips ficorum Marchal (Thysanoptera: Phlaeothripidae), is a critical insect pest of Ficus microcarpa in California urban landscapes and production nurseries. Female thrips feed and oviposit on young Ficus leaves, causing the expanding leaves to fold or curl into a discolored leaf gall. There have been attempts to establish specialist predator natural enemies of the thrips, but no success has been reported. We resampled the same areas in 2013-2014 where we had released Montandoniola confusa (= morguesi) Streito and Matocq (Hemiptera: Anthocoridae) in southern California in 1995 but had been unable to recover individuals in 1997-1998. Thrips galls were significantly reduced in all three of the locations in the recent samples compared with the earlier samples. M. confusa was present in all locations and appears to be providing successful biological control. The value of the biological control, the difference between street trees in good foliage condition and trees with poor foliage, was $58,766,166. If thrips damage reduced the foliage to very poor condition, the value of biological control was $73,402,683. Total cost for the project was $61,830. The benefit accrued for every dollar spent on the biological control of the thrips ranged from $950, if the foliage was in poor condition, to $1,187, if the foliage was in very poor condition. The value of urban forest is often underappreciated. Economic analyses that clearly demonstrate the very substantial rates of return on investment in successful biological control in urban forests provide compelling arguments for supporting future efforts.

  9. Preferences of patients and health professionals for route and frequency of administration of biologic agents in the treatment of rheumatoid arthritis

    DEFF Research Database (Denmark)

    Huynh, Tuan Khai; Ostergaard, Ann; Egsmose, Charlotte;

    2014-01-01

    OBJECTIVES: To examine the preferences of rheumatoid arthritis (RA) patients and health professionals (HPs) for the route and frequency of administration of biologic drugs. METHODS: One hundred and seven RA patients treated with biological agents for intravenous or subcutaneous use, 35 biologic-n...

  10. Controllability and Observability of Leader-Based Multi-agent Systems

    OpenAIRE

    Lozano, Rogelio; Spong, Mark W.; Guerrero, Jose Alfredo; Chopra, Nikhil

    2008-01-01

    International audience; Abstract—In this work we analyze the controllability and observability properties of several interconnection configurations such as the chain topology and cyclic topology as well as combinations of these two topologies. A leader/follower control strategy is proposed to control the center of mass of the multiple agent system. It is shown that the trajectory tracking for a multi-agent system converges to the constant input reference given only to the leader. Also, it is ...

  11. On Feeling in Control: A Biological Theory for Individual Differences in Control Perception

    Science.gov (United States)

    Declerck, Carolyn H.; Boone, Christophe; De Brabander, Bert

    2006-01-01

    This review aims to create a cross-disciplinary framework for understanding the perception of control. Although, the personality trait locus of control, the most common measure of control perception, has traditionally been regarded as a product of social learning, it may have biological antecedents as well. It is suggested that control perception…

  12. Antimicrobial agents used in the control of periodontal biofilms: effective adjuncts to mechanical plaque control?

    Directory of Open Access Journals (Sweden)

    Ricardo Palmier Teles

    2009-06-01

    Full Text Available The control of biofilm accumulation on teeth has been the cornerstone of periodontal disease prevention for decades. However, the widespread prevalence of gingivitis suggests the inefficiency of self-performed mechanical plaque control in preventing gingival inflammation. This is particularly relevant in light of recent evidence suggesting that long standing gingivitis increases the risk of loss of attachment and that prevention of gingival inflammation might reduce the prevalence of mild to moderate periodontitis. Several antimicrobials have been tested as adjuncts to mechanical plaque control in order to improve the results obtained with oral home care. Recent studies, including meta-analyses, have indicated that home care products containing chemical antimicrobials can provide gingivitis reduction beyond what can be accomplished with brushing and flossing. Particularly, formulations containing chlorhexidine, mouthrinses containing essential oils and triclosan/copolymer dentifrices have well documented clinical antiplaque and antigingivitis effects. In vivo microbiological tests have demonstrated the ability of these antimicrobial agents to penetrate the biofilm mass and to kill bacteria growing within biofilms. In addition, chemical antimicrobials can reach difficult-to-clean areas such as interproximal surfaces and can also impact the growth of biofilms on soft tissue. These agents have a positive track record of safety and their use does not seem to increase the levels of resistant species. Further, no study has been able to establish a correlation between mouthrinses containing alcohol and oral cancer. In summary, the adjunct use of chemical plaque control should be recommended to subjects with well documented difficulties in achieving proper biofilm control using only mechanical means.

  13. Antimicrobial agents used in the control of periodontal biofilms: effective adjuncts to mechanical plaque control?

    Science.gov (United States)

    Teles, Ricardo Palmier; Teles, Flavia Rocha Fonseca

    2009-01-01

    The control of biofilm accumulation on teeth has been the cornerstone of periodontal disease prevention for decades. However, the widespread prevalence of gingivitis suggests the inefficiency of self-performed mechanical plaque control in preventing gingival inflammation. This is particularly relevant in light of recent evidence suggesting that long standing gingivitis increases the risk of loss of attachment and that prevention of gingival inflammation might reduce the prevalence of mild to moderate periodontitis. Several antimicrobials have been tested as adjuncts to mechanical plaque control in order to improve the results obtained with oral home care. Recent studies, including meta-analyses, have indicated that home care products containing chemical antimicrobials can provide gingivitis reduction beyond what can be accomplished with brushing and flossing. Particularly, formulations containing chlorhexidine, mouthrinses containing essential oils and triclosan/copolymer dentifrices have well documented clinical antiplaque and antigingivitis effects. In vivo microbiological tests have demonstrated the ability of these antimicrobial agents to penetrate the biofilm mass and to kill bacteria growing within biofilms. In addition, chemical antimicrobials can reach difficult-to-clean areas such as interproximal surfaces and can also impact the growth of biofilms on soft tissue. These agents have a positive track record of safety and their use does not seem to increase the levels of resistant species. Further, no study has been able to establish a correlation between mouthrinses containing alcohol and oral cancer. In summary, the adjunct use of chemical plaque control should be recommended to subjects with well documented difficulties in achieving proper biofilm control using only mechanical means.

  14. CystiSim – An Agent-Based Model for Taenia solium Transmission and Control

    Science.gov (United States)

    Gabriël, Sarah; Dorny, Pierre; Speybroeck, Niko; Magnussen, Pascal; Torgerson, Paul; Johansen, Maria Vang

    2016-01-01

    Taenia solium taeniosis/cysticercosis was declared eradicable by the International Task Force for Disease Eradication in 1993, but remains a neglected zoonosis. To assist in the attempt to regionally eliminate this parasite, we developed cystiSim, an agent-based model for T. solium transmission and control. The model was developed in R and available as an R package (http://cran.r-project.org/package=cystiSim). cystiSim was adapted to an observed setting using field data from Tanzania, but adaptable to other settings if necessary. The model description adheres to the Overview, Design concepts, and Details (ODD) protocol and consists of two entities—pigs and humans. Pigs acquire cysticercosis through the environment or by direct contact with a tapeworm carrier's faeces. Humans acquire taeniosis from slaughtered pigs proportional to their infection intensity. The model allows for evaluation of three interventions measures or combinations hereof: treatment of humans, treatment of pigs, and pig vaccination, and allows for customary coverage and efficacy settings. cystiSim is the first agent-based transmission model for T. solium and suggests that control using a strategy consisting of an intervention only targeting the porcine host is possible, but that coverage and efficacy must be high if elimination is the ultimate goal. Good coverage of the intervention is important, but can be compensated for by including an additional intervention targeting the human host. cystiSim shows that the scenarios combining interventions in both hosts, mass drug administration to humans, and vaccination and treatment of pigs, have a high probability of success if coverage of 75% can be maintained over at least a four year period. In comparison with an existing mathematical model for T. solium transmission, cystiSim also includes parasite maturation, host immunity, and environmental contamination. Adding these biological parameters to the model resulted in new insights in the potential

  15. CystiSim - An Agent-Based Model for Taenia solium Transmission and Control.

    Science.gov (United States)

    Braae, Uffe Christian; Devleesschauwer, Brecht; Gabriël, Sarah; Dorny, Pierre; Speybroeck, Niko; Magnussen, Pascal; Torgerson, Paul; Johansen, Maria Vang

    2016-12-01

    Taenia solium taeniosis/cysticercosis was declared eradicable by the International Task Force for Disease Eradication in 1993, but remains a neglected zoonosis. To assist in the attempt to regionally eliminate this parasite, we developed cystiSim, an agent-based model for T. solium transmission and control. The model was developed in R and available as an R package (http://cran.r-project.org/package=cystiSim). cystiSim was adapted to an observed setting using field data from Tanzania, but adaptable to other settings if necessary. The model description adheres to the Overview, Design concepts, and Details (ODD) protocol and consists of two entities-pigs and humans. Pigs acquire cysticercosis through the environment or by direct contact with a tapeworm carrier's faeces. Humans acquire taeniosis from slaughtered pigs proportional to their infection intensity. The model allows for evaluation of three interventions measures or combinations hereof: treatment of humans, treatment of pigs, and pig vaccination, and allows for customary coverage and efficacy settings. cystiSim is the first agent-based transmission model for T. solium and suggests that control using a strategy consisting of an intervention only targeting the porcine host is possible, but that coverage and efficacy must be high if elimination is the ultimate goal. Good coverage of the intervention is important, but can be compensated for by including an additional intervention targeting the human host. cystiSim shows that the scenarios combining interventions in both hosts, mass drug administration to humans, and vaccination and treatment of pigs, have a high probability of success if coverage of 75% can be maintained over at least a four year period. In comparison with an existing mathematical model for T. solium transmission, cystiSim also includes parasite maturation, host immunity, and environmental contamination. Adding these biological parameters to the model resulted in new insights in the potential

  16. Epigenetics and Why Biological Networks are More Controllable than Expected

    Science.gov (United States)

    Motter, Adilson

    2013-03-01

    A fundamental property of networks is that perturbations to one node can affect other nodes, potentially causing the entire system to change behavior or fail. In this talk, I will show that it is possible to exploit this same principle to control network behavior. This approach takes advantage of the nonlinear dynamics inherent to real networks, and allows bringing the system to a desired target state even when this state is not directly accessible or the linear counterpart is not controllable. Applications show that this framework permits both reprogramming a network to a desired task as well as rescuing networks from the brink of failure, which I will illustrate through various biological problems. I will also briefly review the progress our group has made over the past 5 years on related control of complex networks in non-biological domains.

  17. Controlling the Solidification of Organic Photovoltaic Blends with Nucleating Agents

    KAUST Repository

    Nekuda Malik, Jennifer A.

    2014-11-20

    Blending fullerenes with a donor polymer for the fabrication of organic solar cells often leads to at least partial vitrification of one, if not both, components. For prototypical poly(3-hexylthiophene):fullerene blend, we show that the addition of a commercial nucleating agent, di(3,4-dimethyl benzylidene)sorbitol, to such binary blends accelerates the crystallization of the donor, resulting in an increase in its degree of crystallinity in as-cast structures. This allows manipulation of the extent of intermixing/ phase separation of the donor and acceptor directly from solution, offering a tool to improve device characteristics such as power conversion efficiency.

  18. Sliding mode coordination control for multiagent systems with underactuated agent dynamics

    Science.gov (United States)

    Ghasemi, Masood; Nersesov, Sergey G.; Clayton, Garrett; Ashrafiuon, Hashem

    2014-12-01

    In this paper, we develop a new integrated coordinated control and obstacle avoidance approach for a general class of underactuated agents. We use graph-theoretic notions to characterise communication topology in the network of underactuated agents as determined by the information flow directions and captured by the graph Laplacian matrix. Obstacle avoidance is achieved by surrounding the stationary as well as moving obstacles by elliptical or other convex shapes that serve as stable periodic solutions to planar systems of ordinary differential equations and using transient trajectories of those systems to navigate the agents around the obstacles. Decentralised controllers for individual agents are designed using sliding mode control approach and are only based on data communicated from the neighbouring agents. We demonstrate the efficacy of our theoretical approach using an example of a system of wheeled mobile robots that reach and maintain a desired formation. Finally, we validate our results experimentally.

  19. A theoretical approach on controlling agricultural pest by biological controls.

    Science.gov (United States)

    Mondal, Prasanta Kumar; Jana, Soovoojeet; Kar, T K

    2014-03-01

    In this paper we propose and analyze a prey-predator type dynamical system for pest control where prey population is treated as the pest. We consider two classes for the pest namely susceptible pest and infected pest and the predator population is the natural enemy of the pest. We also consider average delay for both the predation rate i.e. predation to the susceptible pest and infected pest. Considering a subsystem of original system in the absence of infection, we analyze the existence of all possible non-negative equilibria and their stability criteria for both the subsystem as well as the original system. We present the conditions for transcritical bifurcation and Hopf bifurcation in the disease free system. The theoretical evaluations are demonstrated through numerical simulations.

  20. Multi-agent-based bio-network for systems biology: protein-protein interaction network as an example.

    Science.gov (United States)

    Ren, Li-Hong; Ding, Yong-Sheng; Shen, Yi-Zhen; Zhang, Xiang-Feng

    2008-10-01

    Recently, a collective effort from multiple research areas has been made to understand biological systems at the system level. This research requires the ability to simulate particular biological systems as cells, organs, organisms, and communities. In this paper, a novel bio-network simulation platform is proposed for system biology studies by combining agent approaches. We consider a biological system as a set of active computational components interacting with each other and with an external environment. Then, we propose a bio-network platform for simulating the behaviors of biological systems and modelling them in terms of bio-entities and society-entities. As a demonstration, we discuss how a protein-protein interaction (PPI) network can be seen as a society of autonomous interactive components. From interactions among small PPI networks, a large PPI network can emerge that has a remarkable ability to accomplish a complex function or task. We also simulate the evolution of the PPI networks by using the bio-operators of the bio-entities. Based on the proposed approach, various simulators with different functions can be embedded in the simulation platform, and further research can be done from design to development, including complexity validation of the biological system.

  1. Biologically Inspired Self-Stabilizing Control for Bipedal Robots

    Directory of Open Access Journals (Sweden)

    Woosung Yang

    2013-02-01

    Full Text Available Despite recent major advances in computational power and control algorithms, the stable and robust control of a bipedal robot is still a challenging issue due to the complexity and high nonlinearity of robot dynamics. To address the issue an efficient and powerful alternative based on a biologically inspired control framework employing neural oscillators is proposed and tested. In a numerical test the virtual force controller combined with the neural oscillator of a humanoid robot generated rhythmic control signals and stable bipedal locomotion when coupled with proper impedance components. The entrainment nature inherent to neural oscillators also achieved stable and robust walking even in the presence of unexpected disturbances, in that the centre of mass (COM was successfully kept in phase with the zero moment point (ZMP input trajectory. The efficiency of the proposed control scheme is discussed alongside simulation results.

  2. Threshold(trade mark) Immunoassays for Identification of Biological Agents: NATO SIBCA Exercise III

    Science.gov (United States)

    2002-12-01

    le sous-groupe VII de NATO tchanti11onnage et identification des agents biologiques et chimiques (SIBCA) a conduit le troisi~me exercice de...biotest Threshold~m, un biotest avec capteur potentiom~trique adressable de lumi~re (LAPS). Le biotest Threshold~m d’antig~ne de capture 6tait...identification des agents biologiques et chimiques (SIBCA) a organis6 plusieurs exercices internationaux de formation durant lesquels chaque nation participante

  3. Controlled biological and biomimetic systems for landmine detection.

    Science.gov (United States)

    Habib, Maki K

    2007-08-30

    Humanitarian demining requires to accurately detect, locate and deactivate every single landmine and other buried mine-like objects as safely and as quickly as possible, and in the most non-invasive manner. The quality of landmine detection affects directly the efficiency and safety of this process. Most of the available methods to detect explosives and landmines are limited by their sensitivity and/or operational complexities. All landmines leak with time small amounts of their explosives that can be found on surrounding ground and plant life. Hence, explosive signatures represent the robust primary indicator of landmines. Accordingly, developing innovative technologies and efficient techniques to identify in real-time explosives residue in mined areas represents an attractive and promising approach. Biological and biologically inspired detection technology has the potential to compete with or be used in conjunction with other artificial technology to complement performance strengths. Biological systems are sensitive to many different scents concurrently, a property that has proven difficult to replicate artificially. Understanding biological systems presents unique opportunities for developing new capabilities through direct use of trained bio-systems, integration of living and non-living components, or inspiring new design by mimicking biological capabilities. It is expected that controlled bio-systems, biotechnology and microbial techniques will contribute to the advancement of mine detection and other application domains. This paper provides directions, evaluation and analysis on the progress of controlled biological and biomimetic systems for landmine detection. It introduces and discusses different approaches developed, underlining their relative advantages and limitations, and highlighting trends, safety and ecology concern, and possible future directions.

  4. Entomopathogenic fungi as biological controllers: New insights into their virulence and pathogenicity

    Directory of Open Access Journals (Sweden)

    Shahid Ali Ahmad

    2012-01-01

    Full Text Available Entomopathogenic fungi vary considerably in their mode of action and virulence. Successful infection depends primarily on the adherence and penetration ability of a fungus to the host integuments. A variety of extracellular enzymes is produced during the degradation of insect integument. The attempts to control insects have changed over time from chemicals to natural control methods. This is why the development of natural methods of insect control or biopesticides, is preferred. By the use of fungal entomopathogens, insect pests can be controlled. There is no doubt that insects have been used for many years, but their effective use in the field remains elusive. However, their additional role in nature has also been discovered. Comparison of entomopathogens with conventional chemical pesticides depends on their efficiency and cost. In addition to efficiency, there are advantages in using microbial control agents, such as human safety and other non-target organisms; pesticide residues are minimized in food and biodiversity increased in managed ecosystems. In the present review the pathogenicity and virulence of entomopathogenic fungi and their role as biological control agents using biotechnology will be discussed.

  5. Design, synthesis and biological evaluation of di-substituted noscapine analogs as potent and microtubule-targeted anticancer agents.

    Science.gov (United States)

    Mishra, Ram C; Gundala, Sushma R; Karna, Prasanthi; Lopus, Manu; Gupta, Kamlesh K; Nagaraju, Mulpuri; Hamelberg, Donald; Tandon, Vibha; Panda, Dulal; Reid, Michelle D; Aneja, Ritu

    2015-01-01

    Noscapine is an opium-derived kinder-gentler microtubule-modulating drug, currently in Phase I/II clinical trials for cancer chemotherapy. Here, we report the synthesis of four more potent di-substituted brominated derivatives of noscapine, 9-Br-7-OH-NOS (2), 9-Br-7-OCONHEt-NOS (3), 9-Br-7-OCONHBn-NOS (4), and 9-Br-7-OAc-NOS (5) and their chemotherapeutic efficacy on PC-3 and MDA-MB-231 cells. The four derivatives were observed to have higher tubulin binding activity than noscapine and significantly affect tubulin polymerization. The equilibrium dissociation constant (KD) for the interaction between tubulin and 2, 3, 4, 5 was found to be, 55±6μM, 44±6μM, 26±3μM, and 21±1μM respectively, which is comparable to parent analog. The effects of these di-substituted noscapine analogs on cell cycle parameters indicate that the cells enter a quiescent phase without undergoing further cell division. The varying biological activity of these analogs and bulk of substituent at position-7 of the benzofuranone ring system of the parent molecule was rationalized utilizing predictive in silico molecular modeling. Furthermore, the immunoblot analysis of protein lysates from cells treated with 4 and 5, revealed the induction of apoptosis and down-regulation of survivin levels. This result was further supported by the enhanced activity of caspase-3/7 enzymes in treated samples compared to the controls. Hence, these compounds showed a great potential for studying microtubule-mediated processes and as chemotherapeutic agents for the management of human cancers.

  6. Possible reasons for the inefficacy of genetically engineered biological agents in rheumatoid arthritis and ways of its prevention

    Directory of Open Access Journals (Sweden)

    Natalia Vladimirovna Chichasova

    2012-01-01

    Full Text Available Genetically engineered biological agents (GEBAs have held a firm place in the treatment of rheumatoid arthritis (RA. Patients are selected for this treatment in accordance with international and Russian guidelines. The question as to whether GEBAs should be added to therapy with disease-modifying anti-inflammatory drugs (DMAIDs is raised after there is an inadequate response to therapy with two DMAIDs, one of which should be methotrexate. Tumor necrosis factor-α (TNF-α inhibitors as a first-line drug are indicated only in high RA activity. There are few predictors of the efficacy of GEBAs. It is noted that in accordance with the principles of the Treatment to Target program, RA is treated under control of monthly estimated scores in patients with high/moderate disease activity; if there is no remission (with low disease activity being an alternative aim after three months it is decided whether to correct therapy. In routine practice, when the effect of GEBAs, which is observed in many patients in the first week of treatment, appears, physicians often begin to discontinue symptomatic drugs and at times to decrease the dose or withdraw DMAIDs, which may result in the progression of symptoms of arthritis and which may be misinterpreted as the inadequate or none effect of GEBAs. There are objective reasons for the possible inefficacy of GEBAs. The valid predictor for a response to inhibitors of TNF-α is its baseline expression by synovial membrane cells. It is also important to take into account the nature of previous GEBA therapy. All GEBAs are noted to be highly effective when applying a weighed approach to selecting and managing patients; in so doing, rapid discontinuation of symptomatic therapy should be avoided.

  7. Robot Control Using UML and Multi-agent System

    Directory of Open Access Journals (Sweden)

    Ales Pavliska

    2003-02-01

    Full Text Available Increased industrialization and new markets have led to an accumulation of used technical consumer goods, which results in greater exploitation of raw materials, energy and landfill sites. In order to reduce the use of natural resources conserve precious energy and limit the increase in waste volume. The application of disassembly techniques is the first step towards this prevention of waste. These techniques form a reliable and clean approach: "noble" or high-graded recycling. This paper presents a multi agent system for disassembly process, which is implemented in a computer-aided application for supervising of the disassembling system: the Interactive Intelligent Interface for Disassembling System. Unified modeling language diagrams are used for an internal and external definition of the disassembling system.

  8. Coordinated Control of Multi-Agent Systems in Rapidly Varying Environments Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The main objective of this Phase II STTR project is to develop advanced control algorithms that enable multiple autonomous agents to perform complex tasks in rapidly...

  9. Fatigue distribution optimization for offshore wind farms using intelligent agent control

    DEFF Research Database (Denmark)

    Zhao, Rongyong; Shen, Wen Zhong; Knudsen, Torben

    2012-01-01

    A novel control approach is proposed to optimize the fatigue distribution of wind turbines in a large‐scale offshore wind farm on the basis of an intelligent agent theory. In this approach, each wind turbine is considered to be an intelligent agent. The turbine at the farm boundary communicates...... with its neighbouring downwind turbines and organizes them adaptively into a wind delivery group along the wind direction. The agent attributes and the event structure are designed on the basis of the intelligent agent theory by using the unified modelling language. The control strategy of the intelligent...... coefficient for every wind turbine. The optimization is constrained such that the average fatigue for every turbine is smaller than what would be achieved by conventional dispatch and such that the total power loss of the wind farm is restricted to a few percent of the total power. This intelligent agent...

  10. Biological control of wood decay against fungal infection.

    Science.gov (United States)

    Susi, Petri; Aktuganov, Gleb; Himanen, Juha; Korpela, Timo

    2011-07-01

    Wood (timber) is an important raw material for various purposes, and having biological composition it is susceptible to deterioration by various agents. The history of wood protection by impregnation with synthetic chemicals is almost two hundred years old. However, the ever-increasing public concern and the new environmental regulations on the use of chemicals have created the need for the development and the use of alternative methods for wood protection. Biological wood protection by antagonistic microbes alone or in combination with (bio)chemicals, is one of the most promising ways for the environmentally sound wood protection. The most effective biocontrol antagonists belong to genera Trichoderma, Gliocladium, Bacillus, Pseudomonas and Streptomyces. They compete for an ecological niche by consuming available nutrients as well as by secreting a spectrum of biochemicals effective against various fungal pathogens. The biochemicals include cell wall-degrading enzymes, siderophores, chelating iron and a wide variety of volatile and non-volatile antibiotics. In this review, the nature and the function of the antagonistic microbes in wood protection are discussed.

  11. Biological control of banana black Sigatoka disease with Trichoderma

    Directory of Open Access Journals (Sweden)

    Poholl Adan Sagratzki Cavero

    2015-06-01

    Full Text Available Black Sigatoka disease caused by Mycosphaerella fijiensis is the most severe banana disease worldwide. The pathogen is in an invasive phase in Brazil and is already present in most States of the country. The potential of 29 isolates of Trichoderma spp. was studied for the control of black Sigatoka disease under field conditions. Four isolates were able to significantly reduce disease severity and were further tested in a second field experiment. Isolate 2.047 showed the best results in both field experiments and was selected for fungicide sensitivity tests and mass production. This isolate was identified as Trichoderma atroviride by sequencing fragments of the ITS region of the rDNA and tef-1α of the RNA polymerase. Trichoderma atroviride was as effective as the fungicide Azoxystrobin, which is recommended for controlling black Sigatoka. This biocontrol agent has potential to control the disease and may be scaled-up for field applications on rice-based solid fermentation

  12. Biological Control of Olive Green Mold in Agaricus bisporus Cultivation.

    Science.gov (United States)

    Tautorus, T E; Townsley, P M

    1983-02-01

    Successful methods to control the damaging weed mold Chaetomium olivaceum (olive green mold) in mushroom beds are not presently known. An attempt was made to control C. olivaceum by biological means. A thermophilic Bacillus sp. which showed dramatic activity against C. olivaceum on Trypticase soy agar (BBL Microbiology Systems)-0.4% yeast extract agar plates was isolated from commercial mushroom compost (phase I). When inoculated into conventional and hydroponic mushroom beds, the bacillus not only provided a significant degree of protection from C. olivaceum, but also increased yields of Agaricus bisporus.

  13. Decentralized control of ecological and biological networks through Evolutionary Network Control

    Directory of Open Access Journals (Sweden)

    Alessandro Ferrarini

    2016-09-01

    Full Text Available Evolutionary Network Control (ENC has been recently introduced to allow the control of any kind of ecological and biological networks, with an arbitrary number of nodes and links, acting from inside and/or outside. To date, ENC has been applied using a centralized approach where an arbitrary number of network nodes and links could be tamed. This approach has shown to be effective in the control of ecological and biological networks. However a decentralized control, where only one node and the correspondent input/output links are controlled, could be more economic from a computational viewpoint, in particular when the network is very large (i.e. big data. In this view, ENC is upgraded here to realize the decentralized control of ecological and biological nets.

  14. Substituted 3-Benzylcoumarins as Allosteric MEK1 Inhibitors: Design, Synthesis and Biological Evaluation as Antiviral Agents

    Directory of Open Access Journals (Sweden)

    Ping Xu

    2013-05-01

    Full Text Available In order to find novel antiviral agents, a series of allosteric MEK1 inhibitors were designed and synthesized. Based on docking results, multiple optimizations were made on the coumarin scaffold. Some of the derivatives showed excellent MEK1 binding affinity in the appropriate enzymatic assays and displayed obvious inhibitory effects on the ERK pathway in a cellular assay. These compounds also significantly inhibited virus (EV71 replication in HEK293 and RD cells. Several compounds showed potential as agents for the treatment of viral infective diseases, with the most potent compound 18 showing an IC50 value of 54.57 nM in the MEK1 binding assay.

  15. [Practical guide for the use of biological agents in rheumatoid arthritis - December 2011 update].

    Science.gov (United States)

    Mourão, Ana Filipa; Fonseca, João Eurico; Canhão, Helena; Santos, Maria José; Bernardo, Alexandra; Cordeiro, Ana; Cravo, Ana Rita; Ribeiro, Ana; Teixeira, Ana; Barcelos, Anabela; Malcata, Armando; Faustino, Augusto; Duarte, Cátia; Ribeiro, Célia; Nour, Dolores; Araújo, Domingos; Sousa, Elsa; Mariz, Eva; Ramos, Filipa; Vinagre, Filipe; Ventura, Francisco Simões; Sequeira, Graça; Santos, Helena; Branco, Jaime Cunha; Gomes, J A; Silva, J A; Ramos, João; Santo, Jorge Espírito; Costa, José António; Silva, J A; Ribeiro, José Saraiva; Inês, Luís; Miranda, Luís; Sampaio, Luzia; Costa, Maria Lúcia; Rodrigues, Mário; Afonso, Maria Carmo; Cunha, Maria Inês; Saavedra, Maria João; Queiroz, Mário Viana; Couto, Maura; Bernardes, Miguel; Bogas, Mónica; Pinto, Patrícia; Valente, Paula; Coelho, Paulo; Abreu, Pedro; Cortes, Sara; Pimenta, Sofia; Ramiro, Sofia; Figueira, Ricardo; Nóvoa, Teresa

    2011-01-01

    The authors review the practical aspects of biological therapy use for rheumatoid arthritis patients, commenting safety issues before and after treatment initiation and the best treatment strategies to optimize efficacy.

  16. Integrating the Agents of Bioterrorism into the General Biology Curriculum: 1. A Primer on Bioterrorism.

    Science.gov (United States)

    Pommerville, Jeffrey

    2002-01-01

    Reviews the history of and describes what biology educators should know about the topic of bioterrorism. Suggests materials that can be used to communicate more effectively with students and the community and prepare a classroom discussion on bioterrorism. (KHR)

  17. Herbivore-induced plant volatiles to enhance biological control in agriculture.

    Science.gov (United States)

    Peñaflor, M F G V; Bento, J M S

    2013-08-01

    Plants under herbivore attack synthetize defensive organic compounds that directly or indirectly affect herbivore performance and mediate other interactions with the community. The so-called herbivore-induced plant volatiles (HIPVs) consist of odors released by attacked plants that serve as important cues for parasitoids and predators to locate their host/prey. The understanding that has been gained on the ecological role and mechanisms of HIPV emission opens up paths for developing novel strategies integrated with biological control programs with the aim of enhancing the efficacy of natural enemies in suppressing pest populations in crops. Tactics using synthetic HIPVs or chemically/genetically manipulating plant defenses have been suggested in order to recruit natural enemies to plantations or help guiding them to their host more quickly, working as a "synergistic" agent of biological control. This review discusses strategies using HIPVs to enhance biological control that have been proposed in the literature and were categorized here as: (a) exogenous application of elicitors on plants, (b) use of plant varieties that emit attractive HIPVs to natural enemies, (c) release of synthetic HIPVs, and (d) genetic manipulation targeting genes that optimize HIPV emission. We discuss the feasibility, benefits, and downsides of each strategy by considering not only field studies but also comprehensive laboratory assays that present an applied approach for HIPVs or show the potential of employing them in the field.

  18. Uso de agentes microbianos e químico para o controle de Meloidogyne incognita em soja = Use of microbial and chemical agents to control Meloidogyne incognita in soybean

    Directory of Open Access Journals (Sweden)

    Henrique Teixeira Nunes

    2010-07-01

    Full Text Available Nematoides de galhas constituem importante grupo de patógenos da cultura da soja e o manejo integrado é uma das principais medidas de controle que visam à redução de perdas econômicas. Neste trabalho foi avaliada a eficácia dos fungos Paecilomyces lilacinus (Thom. Samsom e Pochonia chlamydosporia (Goddard Zare & Gams (sinonímia Verticillium chlamydosporium, de um produto comercial à base de Bacillus sp. (Nemix e do nematicida químico Aldicarb no controle de Meloidogyne incognita em soja, variedade M-SOY 6101. O experimento foi realizado em casa-de-vegetação no delineamento experimental de blocos casualizados com nove tratamentos (três produtos biológicos usados no tratamento de sementes com ou sem a aplicação em pós-emergência, Aldicarb aplicado apenas em pós-emergência e duastestemunhas e quatro repetições. Aldicarb reduziu o número de ovos e de juvenis do nematoide. P. lilacinus foi o mais atuante dos agentes biológicos, favorecendo a manutenção da quantidade de matéria seca da raiz de soja e reduzindo o número de ovos. O produto Nemix e P. chlamydosporia somente tiveram ação efetiva na redução do número de ovos do nematoide. Com base nos resultados, foi possível concluir que o agente químico e os agentes biológicos avaliados neste trabalho tiveram moderada atividade no controle de M. incognita em soja.Root-knot nematodes are considered significant pathogens of soybean crops. The objective of this work was to evaluate the efficacy of two fungi (Paecilomyces lilacinus (Thom. Samsom and Pochonia chlamydosporia (Goddard Zare & Gams (syn. Verticillium chlamydosporium, a commercial product based on Bacillus sp. and Aldicarb on the control of Meloidogyne incognita on soybean, cultivar M-SOY 6101. The experimental design was set as randomized blocks with four replications. Nine treatments were evaluated: three biological agents used for seed treatment with and without post-emergence application, Aldicarb on post

  19. The Foundation for Application of Multi-Agent Technology In a Holonic Shop Floor Control Architecture

    DEFF Research Database (Denmark)

    Langer, Gilad; Bilberg, Arne

    1997-01-01

    control. The work is based on a theoretical study of new manufacturing systems theories, research of agent multi-agent technology, and two case studies. It is part of a larger research project which aims at developing a multi-cell control architecture based on the Holonic Manufacturing System theory.......The emerging theory regarding Holonic Manufacturing Systems (HMS) presents a advantageous theoretical foundation for the control system of the manufacturing system of the future. Previous research, at the Department, has demonstrated how company tailored shop floor control can be developed...... by applying simulation and cell control enabling technologies. In order to continue this research effort new concepts and theories for shop floor control are investigated. This article presents an overview of the multi-agent concept based on a literature study. This is followed by an investigation regarding...

  20. Guiding Classical Biological Control of an Invasive Mealybug Using Integrative Taxonomy.

    Directory of Open Access Journals (Sweden)

    Aleixandre Beltrà

    Full Text Available Delottococcus aberiae De Lotto (Hemiptera: Pseudococcidae is a mealybug of Southern African origin that has recently been introduced into Eastern Spain. It causes severe distortions on young citrus fruits and represents a growing threat to Mediterranean citrus production. So far, biological control has proven unsatisfactory due to the absence of efficient natural enemies in Spain. Hence, the management of this pest currently relies only on chemical control. The introduction of natural enemies of D. aberiae from the native area of the pest represents a sustainable and economically viable alternative to reduce the risks linked to pesticide applications. Since biological control of mealybugs has been traditionally challenged by taxonomic misidentification, an intensive survey of Delottococcus spp. and their associated parasitoids in South Africa was required as a first step towards a classical biological control programme. Combining morphological and molecular characterization (integrative taxonomy a total of nine mealybug species were identified in this study, including three species of Delottococcus. Different populations of D. aberiae were found on wild olive trees, in citrus orchards and on plants of Chrysanthemoides monilifera, showing intra-specific divergences according to their host plants. Interestingly, the invasive mealybug populations from Spanish orchards clustered together with the population on citrus from Limpopo Province (South Africa, sharing COI haplotypes. This result pointed to an optimum location to collect natural enemies against the invasive mealybug. A total of 14 parasitoid species were recovered from Delottococcus spp. and identified to genus and species level, by integrating morphological and molecular data. A parasitoid belonging to the genus Anagyrus, collected from D. aberiae in citrus orchards in Limpopo, is proposed here as a good biological control agent to be introduced into Spain.

  1. Guiding Classical Biological Control of an Invasive Mealybug Using Integrative Taxonomy

    Science.gov (United States)

    Beltrà, Aleixandre; Addison, Pia; Ávalos, Juan Antonio; Crochard, Didier; Garcia-Marí, Ferran; Guerrieri, Emilio; Giliomee, Jan H.; Malausa, Thibaut; Navarro-Campos, Cristina; Palero, Ferran; Soto, Antonia

    2015-01-01

    Delottococcus aberiae De Lotto (Hemiptera: Pseudococcidae) is a mealybug of Southern African origin that has recently been introduced into Eastern Spain. It causes severe distortions on young citrus fruits and represents a growing threat to Mediterranean citrus production. So far, biological control has proven unsatisfactory due to the absence of efficient natural enemies in Spain. Hence, the management of this pest currently relies only on chemical control. The introduction of natural enemies of D. aberiae from the native area of the pest represents a sustainable and economically viable alternative to reduce the risks linked to pesticide applications. Since biological control of mealybugs has been traditionally challenged by taxonomic misidentification, an intensive survey of Delottococcus spp. and their associated parasitoids in South Africa was required as a first step towards a classical biological control programme. Combining morphological and molecular characterization (integrative taxonomy) a total of nine mealybug species were identified in this study, including three species of Delottococcus. Different populations of D. aberiae were found on wild olive trees, in citrus orchards and on plants of Chrysanthemoides monilifera, showing intra-specific divergences according to their host plants. Interestingly, the invasive mealybug populations from Spanish orchards clustered together with the population on citrus from Limpopo Province (South Africa), sharing COI haplotypes. This result pointed to an optimum location to collect natural enemies against the invasive mealybug. A total of 14 parasitoid species were recovered from Delottococcus spp. and identified to genus and species level, by integrating morphological and molecular data. A parasitoid belonging to the genus Anagyrus, collected from D. aberiae in citrus orchards in Limpopo, is proposed here as a good biological control agent to be introduced into Spain. PMID:26047349

  2. Self-Organized Biological Dynamics and Nonlinear Control

    Science.gov (United States)

    Walleczek, Jan

    2006-04-01

    The frontiers and challenges of biodynamics research Jan Walleczek; Part I. Nonlinear Dynamics in Biology and Response to Stimuli: 1. External signals and internal oscillation dynamics - principal aspects and response of stimulated rhythmic processes Friedemann Kaiser; 2. Nonlinear dynamics in biochemical and biophysical systems: from enzyme kinetics to epilepsy Raima Larter, Robert Worth and Brent Speelman; 3. Fractal mechanisms in neural control: human heartbeat and gait dynamics in health and disease Chung-Kang Peng, Jeffrey M. Hausdorff and Ary L. Goldberger; 4. Self-organising dynamics in human coordination and perception Mingzhou Ding, Yanqing Chen, J. A. Scott Kelso and Betty Tuller; 5. Signal processing in biochemical reaction networks Adam P. Arkin; Part II. Nonlinear Sensitivity of Biological Systems to Electromagnetic Stimuli: 6. Electrical signal detection and noise in systems with long-range coherence Paul C. Gailey; 7. Oscillatory signals in migrating neutrophils: effects of time-varying chemical and electrical fields Howard R. Petty; 8. Enzyme kinetics and nonlinear biochemical amplification in response to static and oscillating magnetic fields Jan Walleczek and Clemens F. Eichwald; 9. Magnetic field sensitivity in the hippocampus Stefan Engström, Suzanne Bawin and W. Ross Adey; Part III. Stochastic Noise-Induced Dynamics and Transport in Biological Systems: 10. Stochastic resonance: looking forward Frank Moss; 11. Stochastic resonance and small-amplitude signal transduction in voltage-gated ion channels Sergey M. Bezrukov and Igor Vodyanoy; 12. Ratchets, rectifiers and demons: the constructive role of noise in free energy and signal transduction R. Dean Astumian; 13. Cellular transduction of periodic and stochastic energy signals by electroconformational coupling Tian Y. Tsong; Part IV. Nonlinear Control of Biological and Other Excitable Systems: 14. Controlling chaos in dynamical systems Kenneth Showalter; 15. Electromagnetic fields and biological

  3. Adaptive Fuzzy-Lyapunov Controller Using Biologically Inspired Swarm Intelligence

    Directory of Open Access Journals (Sweden)

    Alejandro Carrasco Elizalde

    2008-01-01

    Full Text Available The collective behaviour of swarms produces smarter actions than those achieved by a single individual. Colonies of ants, flocks of birds and fish schools are examples of swarms interacting with their environment to achieve a common goal. This cooperative biological intelligence is the inspiration for an adaptive fuzzy controller developed in this paper. Swarm intelligence is used to adjust the parameters of the membership functions used in the adaptive fuzzy controller. The rules of the controller are designed using a computing-with-words approach called Fuzzy-Lyapunov synthesis to improve the stability and robustness of an adaptive fuzzy controller. Computing-with-words provides a powerful tool to manipulate numbers and symbols, like words in a natural language.

  4. Synthesis and biological evaluation of andrographolide derivatives as potent anti-HIV agents

    Institute of Scientific and Technical Information of China (English)

    Bin Wang; Jing Li; Wen Long Huang; Hui Bin Zhang; Hai Qian; Yong Tang Zheng

    2011-01-01

    A series of Andro derivatives were described and evaluated for their anti-HIV activity in vitro. Compound 10 and 16b, of which TI were >10, had some anti-HTV-1 activity in vitro. Therein, compound 10 which was the best potent compound, could serve as a new lead for further development of anti-AIDS agents.

  5. Synthesis and biological evaluation of novel gigantol derivatives as potential agents in prevention of diabetic cataract

    Science.gov (United States)

    As a continuation of our efforts directed towards the development of natural anti-diabetic cataract agents, gigantol was isolated from Herba dendrobii and was found to inhibit both aldose reductase (AR) and inducible nitric oxide synthase (iNOS) activity, which play a significant role in the develop...

  6. Chicken cathelicidin-2-derived peptides with enhanced immunomodulatory and antibacterial activities against biological warfare agents

    NARCIS (Netherlands)

    Molhoek, E.M.; van Dijk, A.; Veldhuizen, E.J.A.; Dijk-Knijnenburg, H.; Mars-Groenendijk, R.H.; Boele, L.C.L.; Kaman, W.E.; Haagsman, H.P.; Bikker, F.J.

    2010-01-01

    Host defence peptides (HDPs) are considered to be excellent candidates for the development of novel therapeutic agents. Recently, it was demonstrated that the peptide C1-15, an N-terminal segment of chicken HDP cathelicidin-2, exhibits potent antibacterial activity while lacking cytotoxicity towards

  7. Radiobiological aspects of high altitude flight: relative biological effectiveness of fast neutrons in suppressing immune capacity to an infective agent. [Mice

    Energy Technology Data Exchange (ETDEWEB)

    Friedberg, W.; Neas, B.R.; Faulkner, D.N.; Hanneman, G.D.; Darden, E.B. Jr.

    1978-02-01

    The authors investigated the relative biological effectiveness (RBE) of fast neutrons compared with x rays in impeding development of immunity to an infective agent, the intestinal cestode Hymenolepis nana. Mice were irradiated with neutrons or x rays and 2 days later given an immunizing dose of H. nana eggs. After another 2 days, the mice received a challenge dose of the eggs. Challenge egg doses were also given to sham-irradiated unimmunized and immunized controls. All mice were killed 90 to 92 hours after challenge, and the H. nana larvae (cysticercoids) that developed in the intestinal tissue were counted. An increased cysticercoid count in the irradiated mice, as compared with the count in unirradiated immunized controls, reflects suppression of immune capacity by the radiation. The results indicate a neutron RBE of 4 at 50 and 101 rad.

  8. A new threat to bees? Entomopathogenic nematodes used in biological pest control cause rapid mortality in Bombus terrestris

    Directory of Open Access Journals (Sweden)

    Alexandrea Dutka

    2015-11-01

    Full Text Available There is currently a great deal of concern about population declines in pollinating insects. Many potential threats have been identified which may adversely affect the behaviour and health of both honey bees and bumble bees: these include pesticide exposure, and parasites and pathogens. Whether biological pest control agents adversely affect bees has been much less well studied: it is generally assumed that biological agents are safer for wildlife than chemical pesticides. The aim of this study was to test whether entomopathogenic nematodes sold as biological pest control products could potentially have adverse effects on the bumble bee Bombus terrestris. One product was a broad spectrum pest control agent containing both Heterorhabditis sp. and Steinernema sp., the other product was specifically for weevil control and contained only Steinernema kraussei. Both nematode products caused ≥80% mortality within the 96 h test period when bees were exposed to soil containing entomopathogenic nematodes at the recommended field concentration of 50 nematodes per cm2 soil. Of particular concern is the fact that nematodes from the broad spectrum product could proliferate in the carcasses of dead bees, and therefore potentially infect a whole bee colony or spread to the wider environment.

  9. A new threat to bees? Entomopathogenic nematodes used in biological pest control cause rapid mortality in Bombus terrestris.

    Science.gov (United States)

    Dutka, Alexandrea; McNulty, Alison; Williamson, Sally M

    2015-01-01

    There is currently a great deal of concern about population declines in pollinating insects. Many potential threats have been identified which may adversely affect the behaviour and health of both honey bees and bumble bees: these include pesticide exposure, and parasites and pathogens. Whether biological pest control agents adversely affect bees has been much less well studied: it is generally assumed that biological agents are safer for wildlife than chemical pesticides. The aim of this study was to test whether entomopathogenic nematodes sold as biological pest control products could potentially have adverse effects on the bumble bee Bombus terrestris. One product was a broad spectrum pest control agent containing both Heterorhabditis sp. and Steinernema sp., the other product was specifically for weevil control and contained only Steinernema kraussei. Both nematode products caused ≥80% mortality within the 96 h test period when bees were exposed to soil containing entomopathogenic nematodes at the recommended field concentration of 50 nematodes per cm(2) soil. Of particular concern is the fact that nematodes from the broad spectrum product could proliferate in the carcasses of dead bees, and therefore potentially infect a whole bee colony or spread to the wider environment.

  10. Multi-Agent Diagnosis and Control of an Air Revitalization System for Life Support in Space

    Science.gov (United States)

    Malin, Jane T.; Kowing, Jeffrey; Nieten, Joseph; Graham, Jeffrey s.; Schreckenghost, Debra; Bonasso, Pete; Fleming, Land D.; MacMahon, Matt; Thronesbery, Carroll

    2000-01-01

    An architecture of interoperating agents has been developed to provide control and fault management for advanced life support systems in space. In this adjustable autonomy architecture, software agents coordinate with human agents and provide support in novel fault management situations. This architecture combines the Livingstone model-based mode identification and reconfiguration (MIR) system with the 3T architecture for autonomous flexible command and control. The MIR software agent performs model-based state identification and diagnosis. MIR identifies novel recovery configurations and the set of commands required for the recovery. The AZT procedural executive and the human operator use the diagnoses and recovery recommendations, and provide command sequencing. User interface extensions have been developed to support human monitoring of both AZT and MIR data and activities. This architecture has been demonstrated performing control and fault management for an oxygen production system for air revitalization in space. The software operates in a dynamic simulation testbed.

  11. Biological control of Tetranychus urticae by Phytoseiulus macropilis and Macrolophus pygmaeus in tomato greenhouses.

    Science.gov (United States)

    Gigon, Vincent; Camps, Cédric; Le Corff, Josiane

    2016-01-01

    Biological control against phytophagous arthropods has been widely used under greenhouse conditions. Its success is dependent on a number of factors related to the abiotic conditions and to the interactions between pests and biological control agents. In particular, when multiple predator species are introduced to suppress one pest, competitive interactions might occur, including intraguild predation (IGP). In tomato crops, the spider mite Tetranychus urticae Koch is a very problematic phytophagous mite and its control is not yet satisfactory. In 2012 and 2013, the ability of a potential new predatory mite Phytoseiulus macropilis (Banks) was assessed, alone and in the presence of Macrolophus pygmaeus Rambur. Macrolophus pygmaeus is a polyphagous mirid supposed to predate on P. macropilis. Both years, under greenhouse conditions, the effectiveness of the two predators was compared between the following treatments: T. urticae, T. urticae + P. macropilis, T. urticae + M. pygmaeus, and T. urticae + P. macropilis + M. pygmaeus. The number of arthropods per tomato plant over time indicated that P. macropilis well-controlled the population of T. urticae, whereas M. pygmaeus had a very limited impact. Furthermore, there was no evidence of IGP between the two predators but in the presence of M. pygmaeus, P. macropilis tended to have a more clumped spatial distribution. Further studies should clarify the number and location of inoculation points to optimize the control of T. urticae by P. macropilis.

  12. Biocontrol of fouling pests: Effect of diversity, identity and density of control agents.

    Science.gov (United States)

    Atalah, Javier; Newcombe, Emma M; Zaiko, Anastasija

    2016-04-01

    Augmentative biocontrol, using native natural enemies, has been suggested as a promising tool to control marine biofouling pests on artificial structures. However, there are still important knowledge gaps to be addressed before biocontrol can be considered as a management tool. In a field experiment on floating marine structures we examined intra- and interspecific consumer interactions among biocontrol agents on different surface orientations. We tested the effect of identity, density and diversity of three invertebrates (the 11-arm seastar Coscinasterias muricata, the sea urchin Evechinus chloroticus and the gastropod Cook's turban Cookia sulcata) to reduce established biofouling and to prevent fouling growth on defouled surfaces. High densities of biocontrol agents were not more effective at fouling control (cover and biomass) than low densities. Nor did multi-species treatments function more effectively than mono-specific ones. However, biocontrol agent identity was important, with the 11-arm seastar and Cook's turban being the most effective at fouling reduction and prevention, respectively. Surface orientation had a strong effect on the effectiveness of control agents, with the best results obtained on vertical compared to diagonal and underside surfaces. This study confirmed the potential of biocontrol as a management tool for marine pest, indicating that identity is more important than richness and density of control agents. It also highlighted the limitations of this approach on diagonal and underside surfaces, where control agents have limited retention ability.

  13. PERFORMANCE EVALUATION FOR DAMPING CONTROLLERS OF POWER SYSTEMS BASED ON MULTI-AGENT MODELS

    Institute of Scientific and Technical Information of China (English)

    Ancheng XUE; Yiguang HONG

    2009-01-01

    This paper proposes a multi-layer multi-agent model for the performance evaluation of power systems, which is different from the existing multi-agent ones. To describe the impact of the structure of the networked power system, .the proposed model consists of three kinds of agents that form three layers: control agents such as the generators and associated controllers, information agents to exchange the information based on the wide area measurement system (WAMS) or transmit control signals to the power system stabilizers (PSSs), and network-node agents such as the generation nodes and load nodes connected with transmission lines. An optimal index is presented to evaluate the performance of damping controllers to the system's inter-area oscillation with respect to the information-layer topology.Then, the authors show that the inter-area information exchange is more powerful than the exchange within a given area to control the inter-area low frequency oscillation based on simulation analysis.

  14. The Use of Software Agents for Autonomous Control of a DC Space Power System

    Science.gov (United States)

    May, Ryan D.; Loparo, Kenneth A.

    2014-01-01

    In order to enable manned deep-space missions, the spacecraft must be controlled autonomously using on-board algorithms. A control architecture is proposed to enable this autonomous operation for an spacecraft electric power system and then implemented using a highly distributed network of software agents. These agents collaborate and compete with each other in order to implement each of the control functions. A subset of this control architecture is tested against a steadystate power system simulation and found to be able to solve a constrained optimization problem with competing objectives using only local information.

  15. An overview of coordinated control for multi-agent systems subject to input saturation

    Directory of Open Access Journals (Sweden)

    Xiaoling Wang

    2016-03-01

    Full Text Available Coordinated control of multi-agent systems has widespread application in engineering such as unmanned aerial vehicles and unmanned ground vehicles. Due to the fact that input saturation can lead a control system to deterioration and instability, a lot of efforts have been devoted to investigating this subject of great importance. The present article offers a survey of recent developments on coordinated control of multi-agents systems subject to input saturation. Some preliminaries about graph theory, stability theory and input saturation are first provided, followed by some important results in the area, which are categorized into semi-global and global coordinated controls. Future research topics are finally discussed.

  16. Combination therapy with biologic agents in rheumatic diseases: current and future prospects

    Science.gov (United States)

    Inui, Kentaro; Koike, Tatsuya

    2016-01-01

    Strategies in rheumatoid arthritis (RA) based on ‘treat to target’ aim to control disease activity, minimize structural damage, and promote longer life. Several disease-modifying antirheumatic drugs (DMARDs) have been shown to be effective including biological DMARDs (bDMARDs). Treatment guidelines and recommendations for RA have also been published. According to those guidelines, conventional synthetic DMARDs (csDMARDs), as monotherapy or combination therapy, should be used in DMARD-naïve patients, irrespective of the addition of glucocorticoids (GCs). Combination therapies with bDMARDs are also essential for conducting treatment strategies for RA, because in every recommendation or guideline for the management of RA, combination therapies of csDMARDs with bDMARDs are recommended for RA patients with moderate or high disease activity after failure of csDMARD treatment. bDMARDs are more efficacious if used concomitantly with methotrexate (MTX) than with MTX monotherapy or bDMARD monotherapy. Thus, retention has been reported to be longer when combined with MTX. The superior efficacy of combination therapy compared with MTX monotherapy or bDMARD monotherapy could be because: (1) it could help to minimize MTX toxicity by reducing the dose of MTX, thus retention rate of the same therapeutic regimen would become high; (2) anti-bDMARD antibodies are observed at lower concentrations when using MTX concomitantly, so less clearance of bDMARDs via less formation of bDMARD and an anti-bDMARD immune complex; (3) of the additive effects of MTX to bDMARD, especially the combination of tumor necrosis factor inhibitors (TNFis) with MTX. Hence, evidence suggests that combination therapy with bDMARDs is more efficacious than monotherapy using a csDMARD or bDMARD, and that MTX is the best drug for this purpose (if MTX is not contraindicated). Finding the most effective drug regimen at the lowest cost will be the aim of RA treatment in the future. PMID:27721905

  17. Feasibility Study of Using Short Wave Infrared Cavity Ringdown Spectroscopy (SWIR-CRDS) for Biological Agent Detection

    Energy Technology Data Exchange (ETDEWEB)

    Aker, Pam M.; Johnson, Timothy J.; Williams, Richard M.; Valentine, Nancy B.

    2007-10-01

    This project focused on determining the feasibility of using short wave infrared (SWIR) cavity ring down spectroscopy (CRDS) as a means for real-time detection of biological aerosols. The first part of the project involved identifying biological agent signatures that could be detected with SWIR CRDS. After an exhaustive search of the open literature it was determined that whole biological spores and/or cells would not be good candidates for direct SWIR CRDS probing because they have no unique SWIR signatures. It was postulated that while whole cells or spores are not good candidates for SWIR CRDS detection, their pyrolysis break-down products might be. A literature search was then conducted to find biological pyrolysis products with low molecular weights and high symmetry since these species most likely would have overtone and combination vibrational bands that can be detected in the SWIR. It was determined that pyrrole, pyridine and picolinamide were good candidates for evaluation. These molecules are formed when proteins and porphyrins, proteins and dipicolinic acid, and dipicolinic acid are pyrolyzed, respectively. The second part of the project involved measuring quantitative SWIR spectra of pyrrole, pyridine and picolinamide in PNNL’s FTIR Spectroscopy Laboratory. Spectral information about these molecules, in the vapor phase is sparse – there were only a few prior studies that measured line positions and no information on absorption cross sections. Absorption cross sections are needed in order to estimate the SWIR CRDS detection sensitivity, and line position determines what type of laser will be needed for the sensor. The results of the spectroscopy studies allowed us to estimate the SWIR CRDS detection sensitivity for pyrrole to be 3 x 1012 molec cm-3 or 0.1 ppmv, and for pyridine it was 1.5 x 1015 molec cm-3 or 0.6 ppmv. These detection sensitivity limits are close what we have measured for ammonia. Given these detection limits we then estimated the

  18. Torymus sinensis: a viable management option for the biological control of Dryocosmus kuriphilus in Europe?

    OpenAIRE

    2014-01-01

    The chestnut gall wasp Dryocosmus kuriphilus is a global pest of chestnut (Castanea spp). Established as a pest in the mid-twentieth century in Japan, Korea and North America, this species was first reported in Europe in 2002. Following the successful release of a biological control agent Torymus sinensis in Japan, this parasitoid species has been released in Italy since 2005. Here we discuss the potential of T. sinensis as a viable management option for the biological control of D. kuriphil...

  19. Voltage Control Method Using Distributed Generators Based on a Multi-Agent System

    Directory of Open Access Journals (Sweden)

    Hyun-Koo Kang

    2015-12-01

    Full Text Available This paper presents a voltage control method using multiple distributed generators (DGs based on a multi-agent system framework. The output controller of each DG is represented as a DG agent, and each voltage-monitoring device is represented as a monitoring agent. These agents cooperate to accomplish voltage regulation through a coordinating agent or moderator. The moderator uses the reactive power sensitivities and margins to determine the voltage control contributions of each DG. A fuzzy inference system (FIS is employed by the moderator to manage the decision-making process. An FIS scheme is developed and optimized to enhance the efficiency of the proposed voltage control process using particle swarm optimization. A simple distribution system with four voltage-controllable DGs is modeled, and an FIS moderator is implemented to control the system. Simulated data show that the proposed voltage control process is able to maintain the system within the operating voltage limits. Furthermore, the results were similar to those obtained using optimal power flow calculations, even though little information on the power system was required and no power flow calculations were implemented.

  20. Biological Stability of Drinking Water: Controlling Factors, Methods, and Challenges

    KAUST Repository

    Prest, Emmanuelle I.

    2016-02-01

    Biological stability of drinking water refers to the concept of providing consumers with drinking water of same microbial quality at the tap as produced at the water treatment facility. However, uncontrolled growth of bacteria can occur during distribution in water mains and premise plumbing, and can lead to hygienic (e.g., development of opportunistic pathogens), aesthetic (e.g., deterioration of taste, odor, color) or operational (e.g., fouling or biocorrosion of pipes) problems. Drinking water contains diverse microorganisms competing for limited available nutrients for growth. Bacterial growth and interactions are regulated by factors, such as (i) type and concentration of available organic and inorganic nutrients, (ii) type and concentration of residual disinfectant, (iii) presence of predators, such as protozoa and invertebrates, (iv) environmental conditions, such as water temperature, and (v) spatial location of microorganisms (bulk water, sediment, or biofilm). Water treatment and distribution conditions in water mains and premise plumbing affect each of these factors and shape bacterial community characteristics (abundance, composition, viability) in distribution systems. Improved understanding of bacterial interactions in distribution systems and of environmental conditions impact is needed for better control of bacterial communities during drinking water production and distribution. This article reviews (i) existing knowledge on biological stability controlling factors and (ii) how these factors are affected by drinking water production and distribution conditions. In addition, (iii) the concept of biological stability is discussed in light of experience with well-established and new analytical methods, enabling high throughput analysis and in-depth characterization of bacterial communities in drinking water. We discussed, how knowledge gained from novel techniques will improve design and monitoring of water treatment and distribution systems in order

  1. Biological stability of drinking water: controlling factors, methods and challenges

    Directory of Open Access Journals (Sweden)

    Emmanuelle ePrest

    2016-02-01

    Full Text Available Biological stability of drinking water refers to the concept of providing consumers with drinking water of same microbial quality at the tap as produced at the water treatment facility. However, uncontrolled growth of bacteria can occur during distribution in water mains and premise plumbing, and can lead to hygienic (e.g. development of opportunistic pathogens, aesthetic (e.g. deterioration of taste, odour, colour or operational (e.g. fouling or biocorrosion of pipes problems. Drinking water contains diverse microorganisms competing for limited available nutrients for growth. Bacterial growth and interactions are regulated by factors such as (i type and concentration of available organic and inorganic nutrients, (ii type and concentration of residual disinfectant, (iii presence of predators such as protozoa and invertebrates, (iv environmental conditions such as water temperature, and (v spatial location of microorganisms (bulk water, sediment or biofilm. Water treatment and distribution conditions in water mains and premise plumbing affect each of these factors and shape bacterial community characteristics (abundance, composition, viability in distribution systems. Improved understanding of bacterial interactions in distribution systems and of environmental conditions impact is needed for better control of bacterial communities during drinking water production and distribution. This article reviews (i existing knowledge on biological stability controlling factors and (ii how these factors are affected by drinking water production and distribution conditions. In addition, (iii the concept of biological stability is discussed in light of experience with well-established and new analytical methods, enabling high throughput analysis and in-depth characterization of bacterial communities in drinking water. We discuss how knowledge gained from novel techniques will improve design and monitoring of water treatment and distribution systems in order to

  2. Biological Stability of Drinking Water: Controlling Factors, Methods, and Challenges

    Science.gov (United States)

    Prest, Emmanuelle I.; Hammes, Frederik; van Loosdrecht, Mark C. M.; Vrouwenvelder, Johannes S.

    2016-01-01

    Biological stability of drinking water refers to the concept of providing consumers with drinking water of same microbial quality at the tap as produced at the water treatment facility. However, uncontrolled growth of bacteria can occur during distribution in water mains and premise plumbing, and can lead to hygienic (e.g., development of opportunistic pathogens), aesthetic (e.g., deterioration of taste, odor, color) or operational (e.g., fouling or biocorrosion of pipes) problems. Drinking water contains diverse microorganisms competing for limited available nutrients for growth. Bacterial growth and interactions are regulated by factors, such as (i) type and concentration of available organic and inorganic nutrients, (ii) type and concentration of residual disinfectant, (iii) presence of predators, such as protozoa and invertebrates, (iv) environmental conditions, such as water temperature, and (v) spatial location of microorganisms (bulk water, sediment, or biofilm). Water treatment and distribution conditions in water mains and premise plumbing affect each of these factors and shape bacterial community characteristics (abundance, composition, viability) in distribution systems. Improved understanding of bacterial interactions in distribution systems and of environmental conditions impact is needed for better control of bacterial communities during drinking water production and distribution. This article reviews (i) existing knowledge on biological stability controlling factors and (ii) how these factors are affected by drinking water production and distribution conditions. In addition, (iii) the concept of biological stability is discussed in light of experience with well-established and new analytical methods, enabling high throughput analysis and in-depth characterization of bacterial communities in drinking water. We discussed, how knowledge gained from novel techniques will improve design and monitoring of water treatment and distribution systems in order

  3. Biological Stability of Drinking Water: Controlling Factors, Methods, and Challenges.

    Science.gov (United States)

    Prest, Emmanuelle I; Hammes, Frederik; van Loosdrecht, Mark C M; Vrouwenvelder, Johannes S

    2016-01-01

    Biological stability of drinking water refers to the concept of providing consumers with drinking water of same microbial quality at the tap as produced at the water treatment facility. However, uncontrolled growth of bacteria can occur during distribution in water mains and premise plumbing, and can lead to hygienic (e.g., development of opportunistic pathogens), aesthetic (e.g., deterioration of taste, odor, color) or operational (e.g., fouling or biocorrosion of pipes) problems. Drinking water contains diverse microorganisms competing for limited available nutrients for growth. Bacterial growth and interactions are regulated by factors, such as (i) type and concentration of available organic and inorganic nutrients, (ii) type and concentration of residual disinfectant, (iii) presence of predators, such as protozoa and invertebrates, (iv) environmental conditions, such as water temperature, and (v) spatial location of microorganisms (bulk water, sediment, or biofilm). Water treatment and distribution conditions in water mains and premise plumbing affect each of these factors and shape bacterial community characteristics (abundance, composition, viability) in distribution systems. Improved understanding of bacterial interactions in distribution systems and of environmental conditions impact is needed for better control of bacterial communities during drinking water production and distribution. This article reviews (i) existing knowledge on biological stability controlling factors and (ii) how these factors are affected by drinking water production and distribution conditions. In addition, (iii) the concept of biological stability is discussed in light of experience with well-established and new analytical methods, enabling high throughput analysis and in-depth characterization of bacterial communities in drinking water. We discussed, how knowledge gained from novel techniques will improve design and monitoring of water treatment and distribution systems in order

  4. Comparative antibacterial activity of silver nanoparticles synthesised by biological and chemical routes with pluronic F68 as a stabilising agent.

    Science.gov (United States)

    Santos, Carolina Alves Dos; Seckler, Marcelo Martins; Ingle, Avinash P; Rai, Mahendra

    2016-08-01

    The authors report the comparative antibacterial activity of silver nanoparticles synthesised by biological (using Fusarium oxysporum) and chemical routes in the presence and absence of pluronic F68 as a stabilising agent. The production of silver nanoparticles was evidenced by UV-visible spectra, with absorbance at about 420 nm in the case of both biological and chemical synthesis. X-ray diffraction pattern confirmed the presence of face-centred cubic structure (FCC plane). The nanoparticles characterised by transmission and scanning electron microscopy showed spherical silver nanoparticles with size range of 5-40 and 10-70 nm in the case of biologically and chemically synthesised nanoparticles, respectively. Addition of pluronic F68 showed the stabilisation of silver nanoparticles. Antibacterial efficacy of silver nanoparticles demonstrated different inhibitory activity against Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus. Overall, biologically synthesised silver nanoparticles showed higher activity as compared with chemically synthesised nanoparticles. Silver nanoparticles synthesised in the presence of pluronic F68 by the chemical route exhibited synergism in antibacterial activity as compared with those synthesised without pluronic F68. On the contrary, biogenic silver nanoparticles without pluronic F68 showed higher antibacterial potential.

  5. Coaxial electrospinning for encapsulation and controlled release of fragile water-soluble bioactive agents.

    Science.gov (United States)

    Jiang, Hongliang; Wang, Liqun; Zhu, Kangjie

    2014-11-10

    Coaxial electrospinning is a robust technique for one-step encapsulation of fragile, water-soluble bioactive agents, including growth factors, DNA and even living organisms, into core-shell nanofibers. The coaxial electrospinning process eliminates the damaging effects due to direct contact of the agents with organic solvents or harsh conditions during emulsification. The shell layer serves as a barrier to prevent the premature release of the water-soluble core contents. By varying the structure and composition of the nanofibers, it is possible to precisely modulate the release of the encapsulated agents. Promising work has been done with coaxially electrospun non-woven mats integrated with bioactive agents for use in tissue engineering, in local delivery and in wound healing, etc. This paper reviews the origins of the coaxial electrospinning method, its updated status and potential future developments for controlled release of the class of fragile, water-soluble bioactive agents.

  6. Short cationic lipopeptides as effective antibacterial agents: Design, physicochemical properties and biological evaluation.

    Science.gov (United States)

    Azmi, Fazren; Elliott, Alysha G; Marasini, Nirmal; Ramu, Soumya; Ziora, Zyta; Kavanagh, Angela M; Blaskovich, Mark A T; Cooper, Matthew A; Skwarczynski, Mariusz; Toth, Istvan

    2016-05-15

    The spread of drug-resistant bacteria has imparted a sense of urgency in the search for new antibiotics. In an effort to develop a new generation of antibacterial agents, we have designed de novo charged lipopeptides inspired by natural antimicrobial peptides. These short lipopeptides are composed of cationic lysine and hydrophobic lipoamino acids that replicate the amphiphilic properties of natural antimicrobial peptides. The resultant lipopeptides were found to self-assemble into nanoparticles. Some were effective against a variety of Gram-positive bacteria, including strains resistant to methicillin, daptomycin and/or vancomycin. The lipopeptides were not toxic to human kidney and liver cell lines and were highly resistant to tryptic degradation. Transmission electron microscopy analysis of bacteria cells treated with lipopeptide showed membrane-damage and lysis with extrusion of cytosolic contents. With such properties in mind, these lipopeptides have the potential to be developed as new antibacterial agents against drug-resistant Gram-positive bacteria.

  7. DNA-damaging agents in cancer chemotherapy: serendipity and chemical biology.

    Science.gov (United States)

    Cheung-Ong, Kahlin; Giaever, Guri; Nislow, Corey

    2013-05-23

    DNA-damaging agents have a long history of use in cancer chemotherapy. The full extent of their cellular mechanisms, which is essential to balance efficacy and toxicity, is often unclear. In addition, the use of many anticancer drugs is limited by dose-limiting toxicities as well as the development of drug resistance. Novel anticancer compounds are continually being developed in the hopes of addressing these limitations; however, it is essential to be able to evaluate these compounds for their mechanisms of action. This review covers the current DNA-damaging agents used in the clinic, discusses their limitations, and describes the use of chemical genomics to uncover new information about the DNA damage response network and to evaluate novel DNA-damaging compounds.

  8. Synthesis and Biological Evaluation of Novel 1-Alkyltryptophan Analogs as Potential Antitumor Agents

    Directory of Open Access Journals (Sweden)

    Shih-Chen Wang

    2009-12-01

    Full Text Available To seek novel antitumor agents, we designed and synthesized new 1-tryptophan analogs based on tryptophan catabolism. 1-Alkyltryptophan analogues including 1-ethyltryptophan (1-ET, 1-propyltryptophan (1-PT, 1-isopropyltryptophan (1-isoPT and 1-butyltryptophan (1-BT were synthesized from tryptophan. We examined whether those compounds had the antiproliferative effects on SGC7901 and HeLa cells line by using MTT assay in vitro, respectively. Compared to tryptophan, all targeted compounds efficiently inhibited proliferation of two cancer cell lines at 2 mmol/L for 48 hours. Among these tryptophan analogs, 1-BT showed the most powerful cytotoxicity against SGC7901 and HeLa cells at 1 mmol/L and 2 mmol/L concentration. These data suggest that some specific tryptophan analogs could be developed as potential anti-neoplastic agents.

  9. Synthetic biology and regulatory networks: where metabolic systems biology meets control engineering.

    Science.gov (United States)

    He, Fei; Murabito, Ettore; Westerhoff, Hans V

    2016-04-01

    Metabolic pathways can be engineered to maximize the synthesis of various products of interest. With the advent of computational systems biology, this endeavour is usually carried out through in silico theoretical studies with the aim to guide and complement further in vitro and in vivo experimental efforts. Clearly, what counts is the result in vivo, not only in terms of maximal productivity but also robustness against environmental perturbations. Engineering an organism towards an increased production flux, however, often compromises that robustness. In this contribution, we review and investigate how various analytical approaches used in metabolic engineering and synthetic biology are related to concepts developed by systems and control engineering. While trade-offs between production optimality and cellular robustness have already been studied diagnostically and statically, the dynamics also matter. Integration of the dynamic design aspects of control engineering with the more diagnostic aspects of metabolic, hierarchical control and regulation analysis is leading to the new, conceptual and operational framework required for the design of robust and productive dynamic pathways.

  10. Enzyme, Antibody, and Photocatalytically Active Nanoscale Scavengers and Sensors for CW and Biological Agents

    Science.gov (United States)

    2008-06-10

    increased the useful life of enzymes in coatings with TiO2 . Selective capture of bacteria by modified coatings: • Antibodies immobilized in...CLASSIFICATION OF: Thin films consisting of photoactive TiO2 and enzyme-functionalized polymer were studied for their activity against chemical agent...simulants. The photochemistry of TiO2 was quantitatively studied for several molecules, including the activation of molecular oxygen which then oxidizes

  11. Study on Biological Control Of Rhizoctonia solani via Trichoderma

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Strain T02-25 was selected from approximately 30 rhizosphere isolates of Trichoderma species isolated from roots of crops. Its biological activity against Rhizoctonia solani was determined for the control efficacy to pepper seedling blight caused by R. solani in the field. The assay methods were treating R. solani sclerotia by Trichoderma conidial suspension (106cfu ml-1) and scattering Thichoderma rice bran over the pepper root medium. The results showed that T02-25 was active against R. solani in both ways, and its control efficacy was 82.7% and 78.0%, respectively. In addition to comparison of the efficacy of the two application methods, the relationship of different factors in the control efficacy of Trichoderma against R. solani was discussed.

  12. Can Chemical Mouthwash Agents Achieve Plaque/Gingivitis Control?

    Science.gov (United States)

    Van der Weijden, Fridus A; Van der Sluijs, Eveline; Ciancio, Sebastian G; Slot, Dagmar E

    2015-10-01

    Also note that structured abstracts are not allowed per journal style: What is the effect of a mouthwash containing various active chemical ingredients on plaque control and managing gingivitis in adults based on evidence gathered from existing systematic reviews? The summarized evidence suggests that mouthwashes containing chlorhexidine(CHX) and essential oils (EO) had a large effect supported by a strong body of evidence. Also there was strong evidence for a moderate effect of cetylpyridinium chloride(CPC). Evidence suggests that a CHX mouthwash is the first choice, the most reliable alternative is EO. No difference between CHX and EO with respect to gingivitis was observed.

  13. Pediatric Asthma: Guidelines-Based Care, Omalizumab, and Other Potential Biologic Agents

    OpenAIRE

    2014-01-01

    Over the past several decades, the evidence supporting rational pediatric asthma management has grown exponentially. As more is learned about the various phenotypes of asthma, the complexity of management will continue to grow. This review focuses on the evidence supporting the current guidelines-based pediatric asthma management and explores the future of asthma management with respect to phenotypic heterogeneity and biologics.

  14. Herpes zoster in psoriasis patients undergoing treatment with biological agents: prevalence, impact, and management challenges

    Directory of Open Access Journals (Sweden)

    el Hayderi L

    2016-10-01

    Full Text Available Lara el Hayderi, Fany Colson, Bita Dezfoulian, Arjen F Nikkels Department of Dermatology, CHU du Sart Tilman, University Hospital of Liège, Liège, Belgium Abstract: As TNF-α is a major factor in the immune defense against herpes zoster (HZ; an increased incidence and severity of HZ cases were suspected in patients undergoing treatment with TNF antagonists. Several studies and clinical experience provided evidence that the incidence of HZ increases by twofold to threefold in this patient category. The number of severe cases of HZ, with multisegmental, disseminated cutaneous, and/or systemic involvement, is also increased. Concerning psoriasis patients under biologicals, the clinician should be more alert for an eventual HZ event, in particular during the first year of biological treatment, and be aware of the possibility of more severe HZ cases. HZ may also undergo an age-shift toward younger patients. Rapid identification of risk factors for severe HZ, such as severe prodromal pains and/or the presence of satellite lesions, is recommended. The treatment recommendations of HZ in this patient group are identical to the recently published guidelines for the management of HZ. The live attenuated viral vaccine OKA/Merck strain anti-HZ vaccination is recommended before initiating biological treatment in psoriasis patients. The new adjuvanted anti-HZ vaccine will probably also benefit patients while on biological treatment. Keywords: herpes zoster, TNF antagonists, anti-IL17, anti-IL12/23, psoriasis, aciclovir

  15. Synthesis and biological evaluation of nitric oxide-releasing matrine derivatives as anticancer agents

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    A series of furoxan-based nitric oxide-releasing matrine derivatives(10a-f) were synthesized.The biological evaluation showed that compounds 10a,10b,10e and 10f had stronger cytotoxic activities than 5-fluorouracil against human hepatoma cells(HepG2) in vitro.

  16. Indoor biology pollution control based on system-based humidity priority control strategy

    Institute of Scientific and Technical Information of China (English)

    刘亚昱; 谢慧; 石博强

    2009-01-01

    Indoor biological contamination and HVAC system secondary contamination problems caused wide public concerns. Biological contamination control will be the next step to achieve better IAQ. The most efficient and safe way to control biological contamination was to limit relative humidity in HVAC system and conditioned environment in the range that is more unsuitable for microorganism to survive. In this paper,by referring to bio-clean project experiences,a system-based humidity priority control manner came into being by lowering outdoor air humidity ratio to eliminate all indoor latent load and using self recirculation units to bear indoor sensible load. Based on the whole-course residue humidity contaminant control concept,dynamic step models for coil and conditioned zone were developed to describe mass and energy conservation and transformation processes. Then,HVAC system and conditioned zone dynamic models were established on LabVIEW+Matlab platform to investigate optimized regulation types,input signatures and control logics. Decoupling between cooling and dehumidification processes can be achieved and a more simplified and stable control system can be acquired by the system-based humidity priority control strategy. Therefore,it was a promising way for controlling biological pollution in buildings in order to achieve better IAQ.

  17. Distributed adaptive fuzzy iterative learning control of coordination problems for higher order multi-agent systems

    Science.gov (United States)

    Li, Jinsha; Li, Junmin

    2016-07-01

    In this paper, the adaptive fuzzy iterative learning control scheme is proposed for coordination problems of Mth order (M ≥ 2) distributed multi-agent systems. Every follower agent has a higher order integrator with unknown nonlinear dynamics and input disturbance. The dynamics of the leader are a higher order nonlinear systems and only available to a portion of the follower agents. With distributed initial state learning, the unified distributed protocols combined time-domain and iteration-domain adaptive laws guarantee that the follower agents track the leader uniformly on [0, T]. Then, the proposed algorithm extends to achieve the formation control. A numerical example and a multiple robotic system are provided to demonstrate the performance of the proposed approach.

  18. Translational systems biology using an agent-based approach for dynamic knowledge representation: An evolutionary paradigm for biomedical research.

    Science.gov (United States)

    An, Gary C

    2010-01-01

    The greatest challenge facing the biomedical research community is the effective translation of basic mechanistic knowledge into clinically effective therapeutics. This challenge is most evident in attempts to understand and modulate "systems" processes/disorders, such as sepsis, cancer, and wound healing. Formulating an investigatory strategy for these issues requires the recognition that these are dynamic processes. Representation of the dynamic behavior of biological systems can aid in the investigation of complex pathophysiological processes by augmenting existing discovery procedures by integrating disparate information sources and knowledge. This approach is termed Translational Systems Biology. Focusing on the development of computational models capturing the behavior of mechanistic hypotheses provides a tool that bridges gaps in the understanding of a disease process by visualizing "thought experiments" to fill those gaps. Agent-based modeling is a computational method particularly well suited to the translation of mechanistic knowledge into a computational framework. Utilizing agent-based models as a means of dynamic hypothesis representation will be a vital means of describing, communicating, and integrating community-wide knowledge. The transparent representation of hypotheses in this dynamic fashion can form the basis of "knowledge ecologies," where selection between competing hypotheses will apply an evolutionary paradigm to the development of community knowledge.

  19. Success evaluation of the biological control of Fusarium wilts of cucumber, banana, and tomato since 2000 and future research strategies.

    Science.gov (United States)

    Raza, Waseem; Ling, Ning; Zhang, Ruifu; Huang, Qiwei; Xu, Yangchun; Shen, Qirong

    2017-03-01

    The Fusarium wilt caused by Fusarium oxysporum strains is the most devastating disease of cucumber, banana, and tomato. The biological control of this disease has become an attractive alternative to the chemical fungicides and other conventional control methods. In this review, the research trends and biological control efficiencies (BCE) of different microbial strains since 2000 are reviewed in detail, considering types of microbial genera, inoculum application methods, plant growth medium and conditions, inoculum application with amendments, and co-inoculation of different microbial strains and how those affect the BCE of Fusarium wilt. The data evaluation showed that the BCE of biocontrol agents was higher against the Fusarium wilt of cucumber compared to the Fusarium wilts of banana and tomato. Several biocontrol agents mainly Bacillus, Trichoderma, Pseudomonas, nonpathogenic Fusarium, and Penicillium strains were evaluated to control Fusarium wilt, but still this lethal disease could not be controlled completely. We have discussed different reasons of inconsistent results and recommendations for the betterment of BCE in the future. This review provides knowledge of the biotechnology of biological control of Fusarium wilt of cucumber, banana, and tomato in a nut shell that will provide researchers a beginning line to start and to organize and plan research for the future studies.

  20. Theory of agent-based market models with controlled levels of greed and anxiety

    Energy Technology Data Exchange (ETDEWEB)

    Papadopoulos, P; Coolen, A C C [Department of Mathematics, King' s College London, The Strand, London WC2R 2LS (United Kingdom)], E-mail: panagiotis.2.papadopoulos@kcl.ac.uk, E-mail: ton.coolen@kcl.ac.uk

    2010-01-15

    We use generating functional analysis to study minority-game-type market models with generalized strategy valuation updates that control the psychology of agents' actions. The agents' choice between trend-following and contrarian trading, and their vigor in each, depends on the overall state of the market. Even in 'fake history' models, the theory now involves an effective overall bid process (coupled to the effective agent process) which can exhibit profound remanence effects and new phase transitions. For some models the bid process can be solved directly, others require Maxwell-construction-type approximations.