WorldWideScience

Sample records for strong biological control

  1. Integrated Biological Control

    International Nuclear Information System (INIS)

    JOHNSON, A.R.

    2002-01-01

    Biological control is any activity taken to prevent, limit, clean up, or remediate potential environmental, health and safety, or workplace quality impacts from plants, animals, or microorganisms. At Hanford the principal emphasis of biological control is to prevent the transport of radioactive contamination by biological vectors (plants, animals, or microorganisms), and where necessary, control and clean up resulting contamination. Other aspects of biological control at Hanford include industrial weed control (e.g.; tumbleweeds), noxious weed control (invasive, non-native plant species), and pest control (undesirable animals such as rodents and stinging insects; and microorganisms such as molds that adversely affect the quality of the workplace environment). Biological control activities may be either preventive (apriori) or in response to existing contamination spread (aposteriori). Surveillance activities, including ground, vegetation, flying insect, and other surveys, and apriori control actions, such as herbicide spraying and placing biological barriers, are important in preventing radioactive contamination spread. If surveillance discovers that biological vectors have spread radioactive contamination, aposteriori control measures, such as fixing contamination, followed by cleanup and removal of the contamination to an approved disposal location are typical response functions. In some cases remediation following the contamination cleanup and removal is necessary. Biological control activities for industrial weeds, noxious weeds and pests have similar modes of prevention and response

  2. Exotic biological control agents

    NARCIS (Netherlands)

    Hajek, Ann E.; Hurley, Brett P.; Kenis, Marc; Garnas, Jeffrey R.; Bush, Samantha J.; Wingfield, Michael J.; Lenteren, van Joop C.; Cock, Matthew J.W.

    2016-01-01

    Biological control is a valuable and effective strategy for controlling arthropod pests and has been used extensively against invasive arthropods. As one approach for control of invasives, exotic natural enemies from the native range of a pest are introduced to areas where control is needed.

  3. 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)

  4. Strong field control of predissociation dynamics.

    Science.gov (United States)

    Corrales, María E; Balerdi, Garikoitz; Loriot, Vincent; de Nalda, Rebeca; Bañares, Luis

    2013-01-01

    Strong field control scenarios are investigated in the CH3I predissociation dynamics at the origin of the second absorption B-band, in which state-selective electronic predissociation occurs through the crossing with a valence dissociative state. Dynamic Stark control (DSC) and pump-dump strategies are shown capable of altering both the predissociation lifetime and the product branching ratio.

  5. Biological activity of soils strongly polluted with sulfur

    Energy Technology Data Exchange (ETDEWEB)

    Krol, M; Maliszewska, W; Siuta, J

    1972-01-01

    Studies were carried out on soils strongly polluted with sulfur and acidified (to pH 1.4). The soils were subjected to an intensive liming. In field and pot experiments, the authors determined: the total quantity of bacteria, actinomycetes, fungi, azotobacter, nitrifiers, proteolytic activity of microorganisms, activity of ammonifiers and the number of sulfur-oxidizing and sulfate-reducing bacteria. It was found that intensive liming of sulfur-affected soils restored their biological activity. 8 references, 5 figures, 1 table.

  6. 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.

  7. Biological control of toxic cyanobacteria

    CSIR Research Space (South Africa)

    Ndlela, L

    2016-04-01

    Full Text Available harmful algal blooms and their impacts in over 30 countries. Biological control is a method of introducing natural enemies to control an organism and has been more successful using microorganisms....

  8. Strong hydrological control on nutrient cycling of subtropical rainforests

    Science.gov (United States)

    Lin, T. C.; Chang, C. T.; Huang, J. C.; Wang, L.; Lin, N. H.

    2016-12-01

    Forest nutrient cycling is strongly controlled by both biological and hydrological factors. However, based on a close examination of earlier reports, we highlight the role of hydrological control on nutrient cycling at a global scale and is more important at humid tropical and subtropical forests. we analyzed the nutrient budget of precipitation input and stream water output from 1994 to 2013 in a subtropical forest in Taiwan and conducted a data synthesis using results from 32 forests across the globe. The results revealed that monthly input and output of ions were positively correlated with water quantity, indicating hydrological control on nutrient cycling. Hydrological control is also evident from the greater ions export via stream water during the warm and wet growing season. The synthesis also illustrates that strong hydrological control leads to lower nitrogen retention and greater net loss of base cations in humid regions, particularly in the humid tropical and subtropical forests. Our result is of great significance in an era of global climate change because climate change could directly affect ecosystem nutrient cycling particularly in the tropics through changes in patterns of precipitation regime.

  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. 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. © 2016 The Author(s).

  11. "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

  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).

  13. 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,…

  14. Biological Control in Brazil: an overview

    OpenAIRE

    Parra,José Roberto Postali

    2014-01-01

    The use of Biological Control methods is on the increase, mainly as a result of the mobilization of human resources in entomology studies since the establishment of graduate programs in this country in the 1960s. This review approaches the retrospective of Biological Control in Brazil in recent decades, with an emphasis on the "culture of applying agrochemicals" adopted by Brazilian growers, which constrains progress in this area. Successful cases of Biological Control have been reported on i...

  15. Review of Pasteuria penetrans: Biology, Ecology, and Biological Control Potential.

    Science.gov (United States)

    Chen, Z X; Dickson, D W

    1998-09-01

    Pasteuria penetrans is a mycelial, endospore-forming, bacterial parasite that has shown great potential as a biological control agent of root-knot nematodes. Considerable progress has been made during the last 10 years in understanding its biology and importance as an agent capable of effectively suppressing root-knot nematodes in field soil. The objective of this review is to summarize the current knowledge of the biology, ecology, and biological control potential of P. penetrans and other Pasteuria members. Pasteuria spp. are distributed worldwide and have been reported from 323 nematode species belonging to 116 genera of free-living, predatory, plant-parasitic, and entomopathogenic nematodes. Artificial cultivation of P. penetrans has met with limited success; large-scale production of endospores depends on in vivo cultivation. Temperature affects endospore attachment, germination, pathogenesis, and completion of the life cycle in the nematode pseudocoelom. The biological control potential of Pasteuria spp. have been demonstrated on 20 crops; host nematodes include Belonolaimus longicaudatus, Heterodera spp., Meloidogyne spp., and Xiphinema diversicaudatum. Pasteuria penetrans plays an important role in some suppressive soils. The efficacy of the bacterium as a biological control agent has been examined. Approximately 100,000 endospores/g of soil provided immediate control of the peanut root-knot nematode, whereas 1,000 and 5,000 endospores/g of soil each amplified in the host nematode and became suppressive after 3 years.

  16. [Screening strains for Trichoderma spp. for strong antagonism against ginseng root pathogens and study on their biological characters].

    Science.gov (United States)

    Zhao, A-Na; Ding, Wan-Long; Zhu, Dian-Long

    2006-10-01

    To screen the Trichodenna spp. for strong antagonist against ginseng root pathogens. The biological characters of ten Trichoderma strains were compared by culturing on different media. And their antagonistic activity against Phytophthora cactorum, Cylindrocarpon destructans and Rhizoctonia solani were measured on PDA. Tv04-2 and Th3080 showed a good growth on soil solution medium and PDA, and also showed high inhibitory efficacy to the three pathogens. The two Trichoderma strains showed different growth rate under light conditions and pH. Trichoderma strains were sensitive to most fungicides used in ginseng root disease controlling, however Tv04-2 was not sensitive to the fungicide Junchong Jueba.

  17. Biological Systems Thinking for Control Engineering Design

    Directory of Open Access Journals (Sweden)

    D. J. Murray-Smith

    2004-01-01

    Full Text Available Artificial neural networks and genetic algorithms are often quoted in discussions about the contribution of biological systems thinking to engineering design. This paper reviews work on the neuromuscular system, a field in which biological systems thinking could make specific contributions to the development and design of automatic control systems for mechatronics and robotics applications. The paper suggests some specific areas in which a better understanding of this biological control system could be expected to contribute to control engineering design methods in the future. Particular emphasis is given to the nonlinear nature of elements within the neuromuscular system and to processes of neural signal processing, sensing and system adaptivity. Aspects of the biological system that are of particular significance for engineering control systems include sensor fusion, sensor redundancy and parallelism, together with advanced forms of signal processing for adaptive and learning control

  18. Opportunities for biological weed control in Europe

    NARCIS (Netherlands)

    Scheepens, P.C.; Müller-Schärer, H.; Kempenaar, C.

    2001-01-01

    The development and application of biological weed control offer greatopportunities not only for farmers, nature conservationists and othervegetation managers but also for institutions and companies that wish tosell plant protection services and products, and for the general publicthat demands safe

  19. Use of nuclear techniques in biological control

    International Nuclear Information System (INIS)

    Greany, Patrick D.; Carpenter, James E.

    2000-01-01

    As pointed out by Benbrook (1996), pest management is at a crossroads, and there is a great need for new, biointensive pest management strategies. Among these approaches, biological control is a keystone. However, because of increasing concerns about the introduction of exotic natural enemies of insect pests and weeds (Howarth 1991, Delfosse 1997), the overall thrust of biological control has moved toward augmentative biological control, involving releases of established natural enemy species (Knipling 1992). This in turn has created a need to develop more cost-effective mass rearing technologies for beneficial insects. Nuclear techniques could play an especially important role in augmentative biological control, not only in facilitating mass rearing, but in several other ways, as indicated below. Recognising the potential value for use of nuclear techniques in biological control, the Insect and Pest Control Section of the Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture, International Atomic Energy Agency, sponsored a Consultants' Group Meeting on this subject in April 1997. The Group produced a document entitled Use of Nuclear Techniques in Biological Control: Managing Pests, Facilitating Trade and Protecting the Environment. The consultants included the authors of this paper as well as Ernest Delfosse (at that time, with the USDA-APHIS National Biological Control Institute), Garry Hill (Intl. Institute for Biological Control), Sinthya Penn (Beneficial Insectary), and Felipe Jeronimo (USDA-APHIS PPQ, Guatemala). The remarks presented in this paper reflect the thoughts presented by these consultants and other participants at the IAEA-sponsored meeting. Several potential uses for nuclear techniques were identified by the Consultants' Group, including: 1) improvements in rearing media (either artificial diets or natural hosts/prey), 2) provision of sterilised natural prey to be used as food during shipment, to ameliorate concerns relating to the

  20. Biological control component [Management of water hyacinth

    International Nuclear Information System (INIS)

    Harley, K.L.S.

    1981-01-01

    Both chemical and biological control have been used with limited success for the management of water hyacinth in Fiji. In some cases heavy application of chemicals have been successful in completely killing limited areas of water hyacinth, but have resulted in the destruction of biological agents introduced to control the water hyacinth and high contamination of natural water supplies. It is proposed that under the direction of Mr S R Singh, the Senior Research Scientist (Entomology) of the Koronivia Research Station, Suva, Fiji, a collaborative programme with Dr Harley of Australia on chemical and biological control of water hyacinth be initiated. This programme would be fundamentally short-term with the prime objective being an investigation of levels of insect population following varying levels of application of chemical sprays. By comparison with control areas, observations would be made of both chemical damage and insect damage within the limited time span of the period

  1. Nonlinear phononics and structural control of strongly correlated materials

    Energy Technology Data Exchange (ETDEWEB)

    Mankowsky, Roman

    2016-01-20

    Mid-infrared light pulses can be used to resonantly excite infrared-active vibrational modes for the phase control of strongly correlated materials on subpicosecond timescales. As the energy is transferred directly into atomic motions, dissipation into the electronic system is reduced, allowing for the emergence of unusual low energy collective properties. Light-induced superconductivity, insulator-metal transitions and melting of magnetic order demonstrate the potential of this method. An understanding of the mechanism, by which these transitions are driven, is however missing. The aim of this work is to uncover this process by investigating the nonlinear lattice dynamics induced by the excitation and to elucidate their contribution to the modulation of collective properties of strongly correlated materials. The first signature of nonlinear lattice dynamics was reported in the observation of coherent phonon oscillations, resonant with the excitation of an infrared-active phonon mode in a manganite. This nonlinear phononic coupling can be described within a model, which predicts not only oscillatory coherent phonons dynamics but also directional atomic displacements along the coupled modes on average, which could cause the previously observed transitions. We verified this directional response and quantified the anharmonic coupling constant by tracing the atomic motions in a time-resolved hard X-ray diffraction experiment with sub-picometer spatial and femtosecond temporal resolution. In a subsequent study, we investigated the role of nonlinear lattice dynamics in the emergence of superconductivity far above the equilibrium transition temperature, an intriguing effect found to follow lattice excitation of YBa{sub 2}Cu{sub 3}O{sub 6+x}. By combining density functional theory (DFT) calculations of the anharmonic coupling constants with time-resolved X-ray diffraction experiments, we identified a structural rearrangement, which appears and decays with the same temporal

  2. Biological effects of electromagnetic fields and recently updated safety guidelines for strong static magnetic fields

    International Nuclear Information System (INIS)

    Yamaguchi-Sekino, Sachiko; Sekino, Masaki; Ueno, Shoogo

    2011-01-01

    Humans are exposed daily to artificial and naturally occurring magnetic fields that originate from many different sources. We review recent studies that examine the biological effects of and medical applications involving electromagnetic fields, review the properties of static and pulsed electromagnetic fields that affect biological systems, describe the use of a pulsed electromagnetic field in combination with an anticancer agent as an example of a medical application that incorporates an electromagnetic field, and discuss the recently updated safety guidelines for static electromagnetic fields. The most notable modifications to the 2009 International Commission on Non-Ionizing Radiation Protection guidelines are the increased exposure limits, especially for those who work with or near electromagnetic fields (occupational exposure limits). The recommended increases in exposure were determined using recent scientific evidence obtained from animal and human studies. Several studies since the 1994 publication of the guidelines have examined the effects on humans after exposure to high static electromagnetic fields (up to 9.4 tesla), but additional research is needed to ascertain further the safety of strong electromagnetic fields. (author)

  3. A functional overview of conservation biological control

    DEFF Research Database (Denmark)

    Begg, Graham S; Cook, Samantha M; Dye, Richard

    2017-01-01

    Conservation biological control (CBC) is a sustainable approach to pest management that can contribute to a reduction in pesticide use as part of an Integrated Pest Management (IPM) strategy. CBC is based on the premise that countering habitat loss and environmental disturbance associated...... CBC prescriptions have proved elusive. To tackle this, we consolidate existing knowledge of CBC using a simple conceptual model that organises the functional elements of CBC into a common, unifying framework. We identify and integrate the key biological processes affecting natural enemies...... and their biological control function across local and regional scales, and consider the interactions, interdependencies and constraints that determine the outcome of CBC strategies. Conservation measures are often effective in supporting natural enemy populations but their success cannot be guaranteed; the greatest...

  4. Characterization and Control of Biological Microrobots

    NARCIS (Netherlands)

    Khalil, I.S.M.; Pichel, Marc Philippe; Pichel, M.P.; Zondervan, L.; Abelmann, Leon; Misra, Sarthak

    2012-01-01

    This work addresses the characterization and control of Magnetotactic Bacterium (MTB) which can be considered as a biological microrobot. Magnetic dipole moment of the MTB and response to a field-with-alternating-direction are characterized. First, the magnetic dipole moment is characterized using

  5. Characterization and control of biological microrobots

    NARCIS (Netherlands)

    Khalil, I.S.M.; Pichel, Marc Philippe; Zondervan, L.; Abelmann, Leon; Misra, Sarthak; Desai, Jaydev P.; Dudek, Gregory; Khatib, Oussama; Kumar, Vijay

    2013-01-01

    This work addresses the characterization and control of Magnetotactic Bacterium (MTB) which can be considered as a biological microrobot. Magnetic dipole moment of the MTB and response to a field-with-alternating-direction are characterized. First, the magnetic dipole moment is characterized using

  6. Incorporating biological control into IPM decision making

    Science.gov (United States)

    Of the many ways biological control can be incorporated into Integrated Pest Management (IPM) programs, natural enemy thresholds are arguably most easily adopted by stakeholders. Integration of natural enemy thresholds into IPM programs requires ecological and cost/benefit crop production data, thr...

  7. Selection of Trichogramma for inundative biological control

    NARCIS (Netherlands)

    Pak, G.A.

    1988-01-01

    This thesis presents a study of the potential for biological control of lepidopterous pests on cabbage crops in the Netherlands, by means of inundative releases of the egg parasite Trichogramma (Hymenoptera, Trichogrammatidae). The objective of this study is to investigate the

  8. Biological control of Meloidogyne incognita by Trichoderma ...

    African Journals Online (AJOL)

    Biological control against the root-knot nematode, Meloidogyne incognita was proven to occur in tomato, Solanum lycopersicom, soil-drenched with different isolates of Trichoderma harzianum and a commercial suspension of Serratia marcescens (Nemaless). The potential of such biocontrol agents to trigger plant defense ...

  9. Strong-Field Control of Laser Filamentation Mechanisms

    Science.gov (United States)

    Levis, Robert; Romanov, Dmitri; Filin, Aleskey; Compton, Ryan

    2008-05-01

    The propagation of short strong-file laser pulses in gas and solution phases often result in formation of filaments. This phenomenon involves many nonlinear processes including Kerr lensing, group velocity dispersion, multi-photon ionization, plasma defocusing, intensity clamping, and self-steepening. Of these, formation and dynamics of pencil-shape plasma areas plays a crucial role. The fundamental understanding of these laser-induced plasmas requires additional effort, because the process is highly nonlinear and complex. We studied the ultrafast laser-generated plasma dynamics both experimentally and theoretically. Ultrafast plasma dynamics was probed using Coherent Anti-Stokes Raman Scattering. The measurements were made in a room temperature gas maintained at 1 atm in a flowing cell. The time dependent scattering was measured by delaying the CARS probe with respect to the intense laser excitation pulse. A general trend is observed between the spacing of the ground state and the first allowed excited state with the rise time for the noble gas series and the molecular gases. This trend is consistent with our theoretical model, which considers the ultrafast dynamics of the strong field generated plasma as a three-step process; (i) strong-field ionization followed by the electron gaining considerable kinetic energy during the pulse; (ii) immediate post-pulse dynamics: fast thermalization, impact-ionization-driven electron multiplication and cooling; (iii) ensuing relaxation: evolution to electron-ion equilibrium and eventual recombination.

  10. Strong stabilization servo controller with optimization of performance criteria.

    Science.gov (United States)

    Sarjaš, Andrej; Svečko, Rajko; Chowdhury, Amor

    2011-07-01

    Synthesis of a simple robust controller with a pole placement technique and a H(∞) metrics is the method used for control of a servo mechanism with BLDC and BDC electric motors. The method includes solving a polynomial equation on the basis of the chosen characteristic polynomial using the Manabe standard polynomial form and parametric solutions. Parametric solutions are introduced directly into the structure of the servo controller. On the basis of the chosen parametric solutions the robustness of a closed-loop system is assessed through uncertainty models and assessment of the norm ‖•‖(∞). The design procedure and the optimization are performed with a genetic algorithm differential evolution - DE. The DE optimization method determines a suboptimal solution throughout the optimization on the basis of a spectrally square polynomial and Šiljak's absolute stability test. The stability of the designed controller during the optimization is being checked with Lipatov's stability condition. Both utilized approaches: Šiljak's test and Lipatov's condition, check the robustness and stability characteristics on the basis of the polynomial's coefficients, and are very convenient for automated design of closed-loop control and for application in optimization algorithms such as DE. Copyright © 2011 ISA. Published by Elsevier Ltd. All rights reserved.

  11. 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.

  12. Strong field coherent control of atomic population transfer

    International Nuclear Information System (INIS)

    Trallero-Herrero, Carlos; Clow, Stephen D; Bergeman, Thomas; Weinacht, Thomas

    2008-01-01

    We demonstrate a population inversion in a three-level system via three-photon absorption from a single shaped ultrafast laser pulse. The optimal pulse shape for the inversion is discovered using closed-loop learning control and interpreted via pulse shape parameter scans and numerical integration of the Schroedinger equation. The population inversion is measured using a combination of spontaneous and stimulated emissions. Our results illustrate the importance of dynamic Stark shifts in coherent multi-photon excitation

  13. Biological control and invading freshwater snails. A case study.

    Science.gov (United States)

    Pointier, J P; Augustin, D

    1999-12-01

    Introductions of four species of freshwater snails occurred between 1972 and 1996 onto Guadeloupe Island. Two of them, Melanoides tuberculata and Marisa cornuarietis, were subsequently used as biological control agents against Biomphalaria glabrata, the snail intermediate host of intestinal schistosomiasis. In 1996, a general survey was carried out in 134 sites which had already been investigated in 1972. The total number of mollusc species had increased from 19 to 21. Site numbers housing B. glabrata and two other species had strongly declined. This decline may be mainly attributed to a competitive displacement by M. tuberculata and M. cornuarietis as illustrated by several biological control programmes. There were no changes in the remainder of the malacological fauna.

  14. BIOLOGICAL CONTROL OF WEEDS BY MEANS OF PLANT PATHOGENS

    OpenAIRE

    Marija Ravlić; Renata Baličević

    2014-01-01

    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 chem...

  15. Biological control of the terrestrial carbon sink

    Science.gov (United States)

    Schulze, E.-D.

    2006-03-01

    different reasons depending on the region of the world: anthropogenic nitrogen deposition is the controlling factor in Europe, increasing global temperatures is the main factor in Siberia, and maybe rising CO2 the factor controlling the carbon fluxes in Amazonia. However, this has not lead to increases in net biome productivity, due to associated losses. Also important is the interaction between biodiversity and biogeochemical processes. It is shown that net primary productivity increases with plant species diversity (50% species loss equals 20% loss in productivity). However, in this extrapolation the action of soil biota is poorly understood although soils contribute the largest number of species and of taxonomic groups to an ecosystem. The global terrestrial carbon budget strongly depends on areas with pristine old growth forests which are carbon sinks. The management options are very limited, mostly short term, and usually associated with high uncertainty. Unmanaged grasslands appear to be a carbon sink of similar magnitude as forest, but generally these ecosystems lost their C with grazing and agricultural use. Extrapolation to the future of Earth climate shows that the biota will not be able to balance fossil fuel emissions, and that it will be essential to develop a carbon free energy system in order to maintain the living conditions on earth.

  16. Biological control of the terrestrial carbon sink

    Directory of Open Access Journals (Sweden)

    E.-D. Schulze

    2006-01-01

    plant growth has different reasons depending on the region of the world: anthropogenic nitrogen deposition is the controlling factor in Europe, increasing global temperatures is the main factor in Siberia, and maybe rising CO2 the factor controlling the carbon fluxes in Amazonia. However, this has not lead to increases in net biome productivity, due to associated losses. Also important is the interaction between biodiversity and biogeochemical processes. It is shown that net primary productivity increases with plant species diversity (50% species loss equals 20% loss in productivity. However, in this extrapolation the action of soil biota is poorly understood although soils contribute the largest number of species and of taxonomic groups to an ecosystem. The global terrestrial carbon budget strongly depends on areas with pristine old growth forests which are carbon sinks. The management options are very limited, mostly short term, and usually associated with high uncertainty. Unmanaged grasslands appear to be a carbon sink of similar magnitude as forest, but generally these ecosystems lost their C with grazing and agricultural use. Extrapolation to the future of Earth climate shows that the biota will not be able to balance fossil fuel emissions, and that it will be essential to develop a carbon free energy system in order to maintain the living conditions on earth.

  17. Biological control of Fusarium moniliforme in maize.

    Science.gov (United States)

    Bacon, C W; Yates, I E; Hinton, D M; Meredith, F

    2001-05-01

    Fusarium moniliforme Sheldon, a biological species of the mating populations within the (italic)Gibberella fujikuroi species complex, i.e., population A [= G. moniliformis (Sheld.) Wineland], is an example of a facultative fungal endophyte. During the biotrophic endophytic association with maize, as well as during saprophytic growth, F. moniliforme produces the fumonisins. The fungus is transmitted vertically and horizontally to the next generation of plants via clonal infection of seeds and plant debris. Horizontal infection is the manner by which this fungus is spread contagiously and through which infection occurs from the outside that can be reduced by application of certain fungicides. The endophytic phase is vertically transmitted. This type infection is important because it is not controlled by seed applications of fungicides, and it remains the reservoir from which infection and toxin biosynthesis takes place in each generation of plants. Thus, vertical transmission of this fungus is just as important as horizontal transmission. A biological control system using an endophytic bacterium, Bacillus subtilis, has been developed that shows great promise for reducing mycotoxin accumulation during the endophytic (vertical transmission) growth phase. Because this bacterium occupies the identical ecological niche within the plant, it is considered an ecological homologue to F. moniliforme, and the inhibitory mechanism, regardless of the mode of action, operates on the competitive exclusion principle. In addition to this bacterium, an isolate of a species of the fungus Trichoderma shows promise in the postharvest control of the growth and toxin accumulation from F. moniliforme on corn in storage.

  18. An Integrated Biological Control System At Hanford

    International Nuclear Information System (INIS)

    Johnson, A.R.; Caudill, J.G.; Giddings, R.F.; Rodriguez, J.M.; Roos, R.C.; Wilde, J.W.

    2010-01-01

    In 1999 an integrated biological control system was instituted at the U.S. Department of Energy's Hanford Site. Successes and changes to the program needed to be communicated to a large and diverse mix of organizations and individuals. Efforts at communication are directed toward the following: Hanford Contractors (Liquid or Tank Waste, Solid Waste, Environmental Restoration, Science and Technology, Site Infrastructure), General Hanford Employees, and Hanford Advisory Board (Native American Tribes, Environmental Groups, Local Citizens, Washington State and Oregon State regulatory agencies). Communication was done through direct interface meetings, individual communication, where appropriate, and broadly sharing program reports. The objectives of the communication efforts was to have the program well coordinated with Hanford contractors, and to have the program understood well enough that all stakeholders would have confidence in the work performed by the program to reduce or elimate spread of radioactive contamination by biotic vectors. Communication of successes and changes to an integrated biological control system instituted in 1999 at the Department of Energy's Hanford Site have required regular interfaces with not only a diverse group of Hanford contractors (i.e., those responsible for liquid or tank waste, solid wastes, environmental restoration, science and technology, and site infrastructure), and general Hanford employees, but also with a consortium of designated stake holders organized as the Hanford Advisory Board (i.e., Native American tribes, various environmental groups, local citizens, Washington state and Oregon regulatory agencies, etc.). Direct interface meetings, individual communication where appropriate, and transparency of the biological control program were the methods and outcome of this effort.

  19. AN INTEGRATED BIOLOGICAL CONTROL SYSTEM AT HANFORD

    Energy Technology Data Exchange (ETDEWEB)

    JOHNSON AR; CAUDILL JG; GIDDINGS RF; RODRIGUEZ JM; ROOS RC; WILDE JW

    2010-02-11

    In 1999 an integrated biological control system was instituted at the U.S. Department of Energy's Hanford Site. Successes and changes to the program needed to be communicated to a large and diverse mix of organizations and individuals. Efforts at communication are directed toward the following: Hanford Contractors (Liquid or Tank Waste, Solid Waste, Environmental Restoration, Science and Technology, Site Infrastructure), General Hanford Employees, and Hanford Advisory Board (Native American Tribes, Environmental Groups, Local Citizens, Washington State and Oregon State regulatory agencies). Communication was done through direct interface meetings, individual communication, where appropriate, and broadly sharing program reports. The objectives of the communication efforts was to have the program well coordinated with Hanford contractors, and to have the program understood well enough that all stakeholders would have confidence in the work performed by the program to reduce or elimated spread of radioactive contamination by biotic vectors. Communication of successes and changes to an integrated biological control system instituted in 1999 at the Department of Energy's Hanford Site have required regular interfaces with not only a diverse group of Hanford contractors (i.e., those responsible for liquid or tank waste, solid wastes, environmental restoration, science and technology, and site infrastructure), and general Hanford employees, but also with a consortium of designated stake holders organized as the Hanford Advisory Board (i.e., Native American tribes, various environmental groups, local citizens, Washington state and Oregon regulatory agencies, etc.). Direct interface meetings, individual communication where appropriate, and transparency of the biological control program were the methods and outcome of this effort.

  20. Biological control of corky root in tomato.

    Science.gov (United States)

    Fiume, G; Fiume, F

    2008-01-01

    Corky root caused by Pyrenochaeta lycopersici (Schneider et Gerlach) is one of the most important soil borne fungal pathogens which develops in the soils, causing diseases in different crops. The research was carried out to evaluate the effectiveness of the biological control of corky root on tomato. Biological control was performed by using Trichoderma viride Pers. 18/17 SS, Streptomyces spp. AtB42 and Bacillus subtilis M51 PI. According to present and future regulations on the use of chemical fungicides and considering that treatments must avoids environmental pollution, the main object of this research was to find alternative strategies by using biocontrol agents against P. lycopersici that affect tomato plants. In laboratory, the effectiveness of T. viride 18/17 SS, Streptomyces spp. AtB42 and B. subtilis M51 PI to control P. lycopersici were studied. In greenhouse, the research was carried out comparing the following treatments: 1) untreated control; 2) T. viride 18/17 SS; 3) Streptomyces spp. AtB42; 4) B. subtilis M51 PI. Roots of plants of tomato H3028 Hazera were treated with the antagonist suspensions just prior of transplant. Treatments were repeated about 2 months after, with the same suspensions sprayed on the soil to the plant collar. In dual culture, the inhibition of P. lycopersici ranged up to 81.2% (caused from T. viride 18/17 SS), 75.6% (from Streptomyces spp. AtB42) and 66.8% (from B. subtilis M51 PI). In greenhouse trials, with regard to corky root symptoms, all treated plots showed signifycative differences compared to untreated. T. viride gave the better results followed by Streptomyces spp. and then by B. subtilis. The fungus antagonist showed good root surface competence such as demonstrated its persistence on the roots surface of the tomato plants whose roots were treated with T. viride 18/17 SS up to 2 months before.

  1. Biological control agents elevate hantavirus by subsidizing deer mouse populations

    Science.gov (United States)

    Dean E. Pearson; Ragan M. Callaway

    2006-01-01

    Biological control of exotic invasive plants using exotic insects is practiced under the assumption that biological control agents are safe if they do not directly attack non-target species. We tested this assumption by evaluating the potential for two host-specific biological control agents (Urophora spp.), widely established in North America for spotted...

  2. Biological Maturity Status Strongly Intensifies the Relative Age Effect in Alpine Ski Racing.

    Directory of Open Access Journals (Sweden)

    Lisa Müller

    Full Text Available The relative age effect (RAE is a well-documented phenomenon in youth sports. This effect exists when the relative age quarter distribution of selected athletes shows a biased distribution with an over-representation of relatively older athletes. In alpine ski racing, it exists in all age categories (national youth levels up to World Cup. Studies so far could demonstrate that selected ski racers are relatively older, taller and heavier. It could be hypothesized that relatively younger athletes nearly only have a chance for selection if they are early maturing. However, surprisingly this influence of the biological maturity status on the RAE could not be proven, yet. Therefore, the aim of the present study was to investigate the influence of the biological maturity status on the RAE in dependence of the level of competition. The study investigated 372 elite youth ski racers: 234 provincial ski racers (P-SR; high level of competition and 137 national ski racers (N-SR; very high level of competition. Anthropometric characteristics were measured to calculate the age at peak height velocity (APHV as an indicator of the biological maturity status. A significant RAE was present among both P-SR and N-SR, with a larger effect size among the latter group. The N-SR significantly differed in APHV from the P-SR. The distribution of normal, early and late maturing athletes significantly differed from the expected normal distribution among the N-SR, not among the P-SR. Hardly any late maturing N-SR were present; 41.7% of the male and 34% of the female N-SR of the last relative age quarter were early maturing. These findings clearly demonstrate the significant influence of the biological maturity status on the selection process of youth alpine ski racing in dependence of the level of competition. Relatively younger athletes seem to have a chance of selection only if they are early maturing.

  3. 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.

  4. Modeling of Nonlinear Propagation in Multi-layer Biological Tissues for Strong Focused Ultrasound

    International Nuclear Information System (INIS)

    Ting-Bo, Fan; Zhen-Bo, Liu; Zhe, Zhang; Dong, Zhang; Xiu-Fen, Gong

    2009-01-01

    A theoretical model of the nonlinear propagation in multi-layered tissues for strong focused ultrasound is proposed. In this model, the spheroidal beam equation (SBE) is utilized to describe the nonlinear sound propagation in each layer tissue, and generalized oblique incidence theory is used to deal with the sound transmission between two layer tissues. Computer simulation is performed on a fat-muscle-liver tissue model under the irradiation of a 1 MHz focused transducer with a large aperture angle of 35°. The results demonstrate that the tissue layer would change the amplitude of sound pressure at the focal region and cause the increase of side petals. (fundamental areas of phenomenology (including applications))

  5. Biological Control of Bacterial Wilt in South East Asia

    OpenAIRE

    Arwiyanto, Triwidodo

    2014-01-01

    Bacterial wilt disease caused by Ralstonia solanacearum destroys many crops of different plant families in South East Asia despite many researches about the disease, and the availability of developed control method in other parts of the world. There is no chemical available for the bacterial wilt pathogen and biological control is then chosen as an alternative to save the crops. Most of the biological control studies were based on antagonism between biological control agent and the pathogen. ...

  6. 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 ...

  7. 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.

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

    NARCIS (Netherlands)

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

    2011-01-01

    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

  9. Effectiveness of a biological control agent Palexorista gilvoides in ...

    African Journals Online (AJOL)

    ACSS

    Effectiveness of a biological control agent Palexorista gilvoides in controlling Gonometa podorcarpi in conifer ... gilvoides as a potential biological control agent for G. podocarpi. Field and laboratory studies further established that P. .... version for windows (SPSS, 2002). Results. Gonometa podocarpi was present in.

  10. Status of biological control in vegetation management in forestry

    Science.gov (United States)

    George P. Markin; Donald E. Gardner

    1993-01-01

    Biological control traditionally depends upon importing the natural enemies of introduced weeds. Since vegetation management in forestry has primarily been aimed at protecting economic species of trees from competition from other native plants, biological control has been of little use in forestry. An alternative approach to controlling unwanted native plants,...

  11. Some strong limit theorems for nonhomogeneous Markov chains indexed by controlled trees

    Directory of Open Access Journals (Sweden)

    Weicai Peng

    2016-02-01

    Full Text Available Abstract In this paper, a kind of infinite, local finite tree T, named a controlled tree, is introduced. Some strong limit properties, such as the strong law of large numbers and the asymptotic equipartition property, for nonhomogeneous Markov chains indexed by T, are established. The outcomes are the generalizations of some well-known results.

  12. Synthetic biology expands chemical control of microorganisms.

    Science.gov (United States)

    Ford, Tyler J; Silver, Pamela A

    2015-10-01

    The tools of synthetic biology allow researchers to change the ways engineered organisms respond to chemical stimuli. Decades of basic biology research and new efforts in computational protein and RNA design have led to the development of small molecule sensors that can be used to alter organism function. These new functions leap beyond the natural propensities of the engineered organisms. They can range from simple fluorescence or growth reporting to pathogen killing, and can involve metabolic coordination among multiple cells or organisms. Herein, we discuss how synthetic biology alters microorganisms' responses to chemical stimuli resulting in the development of microbes as toxicity sensors, disease treatments, and chemical factories. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Understanding Federal regulations as guidelines for classical biological control programs

    Science.gov (United States)

    Michael E. Montgomery

    2011-01-01

    This chapter reviews the legislation and rules that provide the foundation for federal regulation of the introduction of natural enemies of insects as biological control agents. It also outlines the steps for complying with regulatory requirements, using biological control of Adelges tsugae Annand, the hemlock woolly adelgid (HWA), as an example. The...

  14. Efficiency of using green algae as biological controllers against toxic ...

    African Journals Online (AJOL)

    Efficiency of using green algae as biological controllers against toxic algal taxa in cultured ... of two green algal species as biological control of the growth of toxic blue-green algae. ... African Journal of Aquatic Science 2014, 39(4): 443–450 ...

  15. The Control of Chemical and Biological Weapons.

    Science.gov (United States)

    Alexander, Archibald S.; And Others

    This book is composed of four papers prepared to illuminate the problem areas which might arise if the policies of the 1925 Geneva Protocol and other measures to limit chemical and biological weapons are ratified by the United States Senate. The papers included are: Legal Aspects of the Geneva Protocol of 1925; The Use of Herbicides in War: A…

  16. Biological control of livestock pests: Pathogens

    Science.gov (United States)

    Interest in biological methods for livestock and poultry pest management is largely motivated by the development of resistance to most of the available synthetic pesticides by the major pests. There also has been a marked increase in organic systems, and those that promote animal welfare by reducing...

  17. Biological Control Strategies for Mosquito Vectors of Arboviruses.

    Science.gov (United States)

    Huang, Yan-Jang S; Higgs, Stephen; Vanlandingham, Dana L

    2017-02-10

    Historically, biological control utilizes predatory species and pathogenic microorganisms to reduce the population of mosquitoes as disease vectors. This is particularly important for the control of mosquito-borne arboviruses, which normally do not have specific antiviral therapies available. Although development of resistance is likely, the advantages of biological control are that the resources used are typically biodegradable and ecologically friendly. Over the past decade, the advancement of molecular biology has enabled optimization by the manipulation of genetic materials associated with biological control agents. Two significant advancements are the discovery of cytoplasmic incompatibility induced by Wolbachia bacteria, which has enhanced replacement programs, and the introduction of dominant lethal genes into local mosquito populations through the release of genetically modified mosquitoes. As various arboviruses continue to be significant public health threats, biological control strategies have evolved to be more diverse and become critical tools to reduce the disease burden of arboviruses.

  18. Biological Control Strategies for Mosquito Vectors of Arboviruses

    Directory of Open Access Journals (Sweden)

    Yan-Jang S. Huang

    2017-02-01

    Full Text Available Historically, biological control utilizes predatory species and pathogenic microorganisms to reduce the population of mosquitoes as disease vectors. This is particularly important for the control of mosquito-borne arboviruses, which normally do not have specific antiviral therapies available. Although development of resistance is likely, the advantages of biological control are that the resources used are typically biodegradable and ecologically friendly. Over the past decade, the advancement of molecular biology has enabled optimization by the manipulation of genetic materials associated with biological control agents. Two significant advancements are the discovery of cytoplasmic incompatibility induced by Wolbachia bacteria, which has enhanced replacement programs, and the introduction of dominant lethal genes into local mosquito populations through the release of genetically modified mosquitoes. As various arboviruses continue to be significant public health threats, biological control strategies have evolved to be more diverse and become critical tools to reduce the disease burden of arboviruses.

  19. 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. Copyright 2009 Elsevier Inc. All rights reserved.

  20. Biological control of biofilms on membranes by metazoans.

    Science.gov (United States)

    Klein, Theresa; Zihlmann, David; Derlon, Nicolas; Isaacson, Carl; Szivak, Ilona; Weissbrodt, David G; Pronk, Wouter

    2016-01-01

    Traditionally, chemical and physical methods have been used to control biofouling on membranes by inactivating and removing the biofouling layer. Alternatively, the permeability can be increased using biological methods while accepting the presence of the biofouling layer. We have investigated two different types of metazoans for this purpose, the oligochaete Aelosoma hemprichi and the nematode Plectus aquatilis. The addition of these grazing metazoans in biofilm-controlled membrane systems resulted in a flux increase of 50% in presence of the oligochaetes (Aelosoma hemprichi), and a flux increase of 119-164% in presence of the nematodes (Plectus aquatilis) in comparison to the control system operated without metazoans. The change in flux resulted from (1) a change in the biofilm structure, from a homogeneous, cake-like biofilm to a more heterogeneous, porous structure and (2) a significant reduction in the thickness of the basal layer. Pyrosequencing data showed that due to the addition of the predators, also the community composition of the biofilm in terms of protists and bacteria was strongly affected. The results have implications for a range of membrane processes, including ultrafiltration for potable water production, membrane bioreactors and reverse osmosis. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. Biologically inspired rate control of chaos.

    Science.gov (United States)

    Olde Scheper, Tjeerd V

    2017-10-01

    The overall intention of chaotic control is to eliminate chaos and to force the system to become stable in the classical sense. In this paper, I demonstrate a more subtle method that does not eliminate all traces of chaotic behaviour; yet it consistently, and reliably, can provide control as intended. The Rate Control of Chaos (RCC) method is derived from metabolic control processes and has several remarkable properties. RCC can control complex systems continuously, and unsupervised, it can also maintain control across bifurcations, and in the presence of significant systemic noise. Specifically, I show that RCC can control a typical set of chaotic models, including the 3 and 4 dimensional chaotic Lorenz systems, in all modes. Furthermore, it is capable of controlling spatiotemporal chaos without supervision and maintains control of the system across bifurcations. This property of RCC allows a dynamic system to operate in parameter spaces that are difficult to control otherwise. This may be particularly interesting for the control of forced systems or dynamic systems that are chaotically perturbed. These control properties of RCC are applicable to a range of dynamic systems, thereby appearing to have far-reaching effects beyond just controlling chaos. RCC may also point to the existence of a biochemical control function of an enzyme, to stabilise the dynamics of the reaction cascade.

  2. JC Polyomavirus Infection Is Strongly Controlled by Human Leucocyte Antigen Class II Variants

    DEFF Research Database (Denmark)

    Sundqvist, Emilie; Buck, Dorothea; Warnke, Clemens

    2014-01-01

    sequence-specific oligonucleotide (PCR-SSO) method. An initial GWAS screen displayed a strong HLA class II region signal. The HLA-DRB1*15 haplotype was strongly negatively associated to JCV sero-status in Scandinavian MS cases (OR = 0.42, p = 7×10(-15)) and controls (OR = 0.53, p = 2×10(-5)). In contrast...

  3. Operating wind turbines in strong wind conditions by using feedforward-feedback control

    International Nuclear Information System (INIS)

    Feng, Ju; Sheng, Wen Zhong

    2014-01-01

    Due to the increasing penetration of wind energy into power systems, it becomes critical to reduce the impact of wind energy on the stability and reliability of the overall power system. In precedent works, Shen and his co-workers developed a re-designed operation schema to run wind turbines in strong wind conditions based on optimization method and standard PI feedback control, which can prevent the typical shutdowns of wind turbines when reaching the cut-out wind speed. In this paper, a new control strategy combing the standard PI feedback control with feedforward controls using the optimization results is investigated for the operation of variable-speed pitch-regulated wind turbines in strong wind conditions. It is shown that the developed control strategy is capable of smoothening the power output of wind turbine and avoiding its sudden showdown at high wind speeds without worsening the loads on rotor and blades

  4. Biology of Leptoypha hospita (Hemiptera: Tingidae), a Potential Biological Control Agent of Chinese Privet

    Science.gov (United States)

    Yanzhuo Zhang; James L. Hanula; Scott Horn; Kristine Braman; Jianghua Sun

    2011-01-01

    The biology of Leptoypha hospita Drake et Poor (Hemiptera: Tingidae), a potential biological control agent from China for Chinese privet, Ligustrum sinense Lour., was studied in quarantine in the United States. Both nymphs and adults feed on Chinese privet mesophyll cells that lead to a bleached appearance of leaves and dieback of branch tips. L. hospita has five...

  5. Biological Control of Plant Disease Caused by Bacteria

    Directory of Open Access Journals (Sweden)

    Triwidodo Arwiyanto

    2014-07-01

    Full Text Available Bacterial diseases in plants are difficult to control. The emphasis is on preventing the spread of the bacteria rather than curing the diseased plant. Integrated management measures for bacterial plant pathogens should be applied for successfull control. Biological control is one of the control measures viz. through the use of microorganisms to suppress the growth and development of bacterial plant pathogen and ultimately reduce the possibility of disease onset. The study of biological control of bacterial plant pathogen was just began compared with of fungal plant pathogen. The ecological nature of diverse bacterial plant pathogens has led scientists to apply different approach in the investigation of its biological control. The complex process of entrance to its host plant for certain soil-borne bacterial plant pathogens need special techniques and combination of more than one biological control agent. Problem and progress in controlling bacterial plant pathogens biologically will be discussed in more detail in the paper and some commercial products of biological control agents (biopesticides will be introduced.     Penyakit tumbuhan karena bakteri sulit dikendalikan. Penekanan pengendalian adalah pada pencegahan penyebaran bakteri patogen dan bukan pada penyembuhan tanaman yang sudah sakit. Untuk suksesnya pengendalian bakteri patogen tumbuhan diperlukan cara pengelolaan yang terpadu. Pengendalian secara biologi merupakan salah satu cara pengendalian dengan menggunakan mikroorganisme untuk menekan pertumbuhan dan perkembangan bakteri patogen tumbuhan dengan tujuan akhir menurunkan kemungkinan timbulnya penyakit. Sifat ekologi bakteri patogen tumbuhan yang berbeda-beda mengharuskan pendekatan yang berbeda pula dalam pengendaliannya secara biologi. Masalah dan perkembangan dalam pengendalian bakteri patogen tumbuhan secara biologi didiskusikan secara detail dalam makalah ini.

  6. Biological Control of Bacterial Wilt in South East Asia

    Directory of Open Access Journals (Sweden)

    Triwidodo Arwiyanto

    2014-12-01

    Full Text Available Bacterial wilt disease caused by Ralstonia solanacearum destroys many crops of different plant families in South East Asia despite many researches about the disease, and the availability of developed control method in other parts of the world. There is no chemical available for the bacterial wilt pathogen and biological control is then chosen as an alternative to save the crops. Most of the biological control studies were based on antagonism between biological control agent and the pathogen. The biological control agents were intended to reduce the initial inoculum of the pathogen. The effort to minimize the initial inoculum of the pathogen by baiting with the use of hypersensitive host-plant was only reliable when conducted in the greenhouse experiments. Various microorganisms have been searched as possible biological control agents, for instance avirulent form of the pathogen, soil or rhizosphere bacteria (Bacillus spp. and fluorescent pseudomonads, actinomycetes (Streptomyces spp., yeast (Pichia uillermondii, Candida ethanolica, and a consortium of microorganisms known as effective microorganisms (EM. None of these biological control agents has been used in field application and they need further investigation in order to effectively control bacterial wilt. Opportunities and challenges in developing biological control to combat bacterial wilt are discussed in the paper. Penyakit layu bakteri yang disebabkan oleh Ralstonia solanacearum menghancurkan banyak tanaman dalam famili yang berbeda di Asia Tenggara meskipun telah banyak penelitian tentang metode pengendaliannya. Penyakit ini sulit dikendalikan karena banyaknya variabilitas patogen dan belum tersedianya sumber ketahanan yang mapan. Di samping itu, sampai saat ini belum ada bahan kimia yang tersedia untuk patogen layu bakteri ini sehingga pengendalian biologi kemudian dipilih sebagai cara alternatif untuk menyelamatkan tanaman. Sebagian besar penelitian pengendalian biologi didasarkan

  7. Explaining Biological Functionality: Is Control Theory Enough ...

    African Journals Online (AJOL)

    I argue that the etiological approach, as understood in terms of control theory, suffers from a problem of symmetry, by which function can equally well be placed in the environment as in the organism. Focusing on the autonomy view, I note that it can be understood to some degree in terms of control theory in its version called ...

  8. Microbiome studies in the biological control of plant pathogens

    Science.gov (United States)

    Biological control of plant pathogens, although it has been a successful alternative that has allowed to select microorganisms for the generation of bioproducts and to understand multiple biological mechanisms, cannot be considered as a strategy defined only from the selection of a range of cultiva...

  9. Strong tobacco control program requirements and secure funding are not enough: lessons from Florida.

    Science.gov (United States)

    Kennedy, Allison; Sullivan, Sarah; Hendlin, Yogi; Barnes, Richard; Glantz, Stanton

    2012-05-01

    Florida's Tobacco Pilot Program (TPP; 1998-2003), with its edgy Truth media campaign, achieved unprecedented youth smoking reductions and became a model for tobacco control programming. In 2006, 3 years after the TPP was defunded, public health groups restored funding for tobacco control programming by convincing Florida voters to amend their constitution. Despite the new program's strong legal structure, Governor Charlie Crist's Department of Health implemented a low-impact program. Although they secured the program's strong structure and funding, Florida's nongovernmental public health organizations did not mobilize to demand a high-impact program. Implementation of Florida's Amendment 4 demonstrates that a strong programmatic structure and secure funding are insufficient to ensure a successful public health program, without external pressure from nongovernmental groups.

  10. Optimal Control Strategy for Marine Ssp Podded Propulsion Motor Based on Strong Tracking-Epf

    Directory of Open Access Journals (Sweden)

    Yao Wenlong

    2015-09-01

    Full Text Available Aiming at the non-linearity of state equation and observation equation of SSP (Siemen Schottel Propulsor propulsion motor, an improved particle filter algorithm based on strong tracking extent Kalman filter (ST-EKF was presented, and it was imported into the marine SSP propulsion motor control system. The strong tracking filter was used to update particles in the new algorithm and produce importance densities. As a result, the problems of particle degeneracy and sample impoverishment were ameliorated, the propulsion motor states and the rotor resistance were estimated simultaneously using strong track filter (STF, and the tracking ability of marine SSP propulsion motor control system was improved. Simulation result shown that the improved EPF algorithm was not only improving the prediction accuracy of the motor states and the rotor resistance, but also it can satisfy the requirement of navigation in harbor. It had the better accuracy than EPF algorithm.

  11. 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.

  12. 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....

  13. Isolation of microorganisms for biological control the moniliophthora roreri

    OpenAIRE

    suarez contreras, liliana yanet; Rangel Riaño, Alba Luz

    2014-01-01

    Moniliophlhora roreri is the causal agent of cocoa Moniliasis, which produces losses of up to 60% of the crop, as it affects only its commercial product, the cob. Biological control appears as an alternative management, using endophytic microorganisms. The reason because of this research came up was that it was aimed to isolate microorganisms with antagonist potential for biological control towards the phytopathogen M. roreri in Norte de Santander. This is done through isolation and identifica...

  14. Biology and control of hemlock woolly adelgid

    Science.gov (United States)

    Nathan P. Havill; Ligia C. Vieira; Scott M. Salom

    2014-01-01

    This publication is a substantial revision of FHTET 2001-03, Hemlock Woolly Adelgid, which was published in 2001. This publication contains information on the native range of hemlock and range of hemlock woolly adelgid, the importance of hemlocks in eastern forest ecosystems, and on hosts, life cycle, control, and population trends of the hemlock woolly adelgid.

  15. 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.

  16. 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)

  17. Motivational incentives lead to a strong increase in lateral prefrontal activity after self-control exertion.

    Science.gov (United States)

    Luethi, Matthias S; Friese, Malte; Binder, Julia; Boesiger, Peter; Luechinger, Roger; Rasch, Björn

    2016-10-01

    Self-control is key to success in life. Initial acts of self-control temporarily impair subsequent self-control performance. Why such self-control failures occur is unclear, with prominent models postulating a loss of a limited resource vs a loss of motivation, respectively. Here, we used functional magnetic resonance imaging to identify the neural correlates of motivation-induced benefits on self-control. Participants initially exerted or did not exert self-control. In a subsequent Stroop task, participants performed worse after exerting self-control, but not if they were motivated to perform well by monetary incentives. On the neural level, having exerted self-control resulted in decreased activation in the left inferior frontal gyrus. Increasing motivation resulted in a particularly strong activation of this area specifically after exerting self-control. Thus, after self-control exertion participants showed more prefrontal neural activity without improving performance beyond baseline level. These findings suggest that impaired performance after self-control exertion may not exclusively be due to a loss of motivation. © The Author (2016). Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.

  18. Local and global control of ecological and biological networks

    OpenAIRE

    Alessandro Ferrarini

    2014-01-01

    Recently, I introduced a methodological framework so that ecological and biological networks can be controlled both from inside and outside by coupling network dynamics and evolutionary modelling. The endogenous control requires the network to be optimized at the beginning of its dynamics (by acting upon nodes, edges or both) so that it will then go inertially to the desired state. Instead, the exogenous control requires that exogenous controllers act upon the network at each time step. By th...

  19. Complete Coherent Control of a Quantum Dot Strongly Coupled to a Nanocavity

    Science.gov (United States)

    Dory, Constantin; Fischer, Kevin A.; Müller, Kai; Lagoudakis, Konstantinos G.; Sarmiento, Tomas; Rundquist, Armand; Zhang, Jingyuan L.; Kelaita, Yousif; Vučković, Jelena

    2016-04-01

    Strongly coupled quantum dot-cavity systems provide a non-linear configuration of hybridized light-matter states with promising quantum-optical applications. Here, we investigate the coherent interaction between strong laser pulses and quantum dot-cavity polaritons. Resonant excitation of polaritonic states and their interaction with phonons allow us to observe coherent Rabi oscillations and Ramsey fringes. Furthermore, we demonstrate complete coherent control of a quantum dot-photonic crystal cavity based quantum-bit. By controlling the excitation power and phase in a two-pulse excitation scheme we achieve access to the full Bloch sphere. Quantum-optical simulations are in good agreement with our experiments and provide insight into the decoherence mechanisms.

  20. Complete Coherent Control of a Quantum Dot Strongly Coupled to a Nanocavity.

    Science.gov (United States)

    Dory, Constantin; Fischer, Kevin A; Müller, Kai; Lagoudakis, Konstantinos G; Sarmiento, Tomas; Rundquist, Armand; Zhang, Jingyuan L; Kelaita, Yousif; Vučković, Jelena

    2016-04-26

    Strongly coupled quantum dot-cavity systems provide a non-linear configuration of hybridized light-matter states with promising quantum-optical applications. Here, we investigate the coherent interaction between strong laser pulses and quantum dot-cavity polaritons. Resonant excitation of polaritonic states and their interaction with phonons allow us to observe coherent Rabi oscillations and Ramsey fringes. Furthermore, we demonstrate complete coherent control of a quantum dot-photonic crystal cavity based quantum-bit. By controlling the excitation power and phase in a two-pulse excitation scheme we achieve access to the full Bloch sphere. Quantum-optical simulations are in good agreement with our experiments and provide insight into the decoherence mechanisms.

  1. Biological control by ( Coccinella algerica , Kovar 1977) against the ...

    African Journals Online (AJOL)

    Inputs from chemicals, particularly pesticides, to control crop pests have adverse effects on soil and the environment, among others. To reduce pest attacks, biological control with indigenous predators is the alternative and the cleanest, most environmentally friendly and ecologically balanced way. In order to achieve this ...

  2. 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

  3. Nematodes for the biological control of the woodwasp, Sirex noctilio

    Science.gov (United States)

    Robin A. Bedding

    2007-01-01

    The tylenchid nematode Beddingia (Deladenus) siricidicola (Bedding) is by far the most important control agent of Sirex noctilio F., a major pest of pine plantations. It sterilizes female sirex, is density dependent, can achieve nearly 100 percent parasitism and, as a result of its complicated biology can be readily manipulated for sirex control. Bedding and Iede (2005...

  4. Lactate dehydrogenase has no control on lactate production but has a strong negative control on formate production in Lactococcus lactis

    DEFF Research Database (Denmark)

    Andersen, H.W.; Pedersen, M.B.; Hammer, Karin

    2001-01-01

    enhanced in the strain deleted for lactate dehydrogenase. What is more surprising is that the enzyme had a strong negative control (C- LDH(F1)J=-1.3) on the flux to formate at the wild-type level of lactate dehydrogenase. Furthermore, we showed that L. lactis has limited excess of capacity of lactate...

  5. Strong-field spatiotemporal ultrafast coherent control in three-level atoms

    International Nuclear Information System (INIS)

    Bruner, Barry D.; Suchowski, Haim; Silberberg, Yaron; Vitanov, Nikolay V.

    2010-01-01

    Simple analytical approaches for implementing strong field coherent control schemes are often elusive due to the complexity of the interaction between the intense excitation field and the system of interest. Here, we demonstrate control over multiphoton excitation in a three-level resonant system using simple, analytically derived ultrafast pulse shapes. We utilize a two-dimensional spatiotemporal control technique, in which temporal focusing produces a spatially dependent quadratic spectral phase, while a second, arbitrary phase parameter is scanned using a pulse shaper. In the current work, we demonstrate weak-to-strong field excitation of 85 Rb, with a π phase step and the quadratic phase as the chosen control parameters. The intricate dependence of the multilevel dynamics on these parameters is exhibited by mapping the data onto a two-dimensional control landscape. Further insight is gained by simulating the complete landscape using a dressed-state, time-domain model, in which the influence of individual shaping parameters can be extracted using both exact and asymptotic time-domain representations of the dressed-state energies.

  6. Understanding strong-field coherent control: Measuring single-atom versus collective dynamics

    International Nuclear Information System (INIS)

    Trallero-Herrero, Carlos; Weinacht, Thomas; Spanner, Michael

    2006-01-01

    We compare the results of two strong field coherent control experiments: one which optimizes multi-photon population transfer in atomic sodium (from the 3s to the 4s state, measured by spontaneous emission from the 3p-3s transition) with one that optimizes stimulated emission on the 3p-3s transition in an ensemble of sodium atoms. Both experiments make use of intense, shaped ultrafast laser pulses discovered by a Genetic Algorithm inside a learning control loop. Optimization leads to improvements in the spontaneous and stimulated emission yields of about 4 and 10 4 , respectively, over an unshaped pulse. We interpret these results by modeling both the single atom dynamics as well as the stimulated emission buildup through numerical integration of Schroedinger's and Maxwell's equations. Our interpretation leads to the conclusion that modest yields for controlling single quantum systems can lead to dramatic effects whenever an ensemble of such systems acts collectively following controlled impulsive excitation

  7. Biological control of Mycosphaerella fragariae in strawberry culture

    Directory of Open Access Journals (Sweden)

    Anderson Luis Heling

    2015-12-01

    Full Text Available The Mycosphaerella spot is one of the main foliar diseases of strawberry, degrating great leaf regions and reducing the photosynthetic area. Its control is mainly by the use of chemical fungicides, but, due the increasing demand for food free of pesticide, alternative control methods have been researched, such as biological control. This work aimed to evaluate the effect on strawberry plants, treated with the biological control agents Bacillus cereus, Saccharomyces boulardii and Saccharomyces cerevisiae, in the severity of Mycosphaerella fragariae, productivity and in the activity of β-1.3 glucanases, peroxidases and chitinases enzymes. It was verified that S. cerevisiae and B. cereus treatments were similar to fungicide for disease control. However, even reducing the severity of the disease, there was no increase in productivity, and the different control agents do not cause changes in the evaluated defense mechanisms.

  8. Strong Functional Connectivity among Homotopic Brain Areas Is Vital for Motor Control in Unilateral Limb Movement

    Directory of Open Access Journals (Sweden)

    Pengxu Wei

    2017-07-01

    Full Text Available The mechanism underlying brain region organization for motor control in humans remains poorly understood. In this functional magnetic resonance imaging (fMRI study, right-handed volunteers were tasked to maintain unilateral foot movements on the right and left sides as consistently as possible. We aimed to identify the similarities and differences between brain motor networks of the two conditions. We recruited 18 right-handed healthy volunteers aged 25 ± 2.3 years and used a whole-body 3T system for magnetic resonance (MR scanning. Image analysis was performed using SPM8, Conn toolbox and Brain Connectivity Toolbox. We determined a craniocaudally distributed, mirror-symmetrical modular structure. The functional connectivity between homotopic brain areas was generally stronger than the intrahemispheric connections, and such strong connectivity led to the abovementioned modular structure. Our findings indicated that the interhemispheric functional interaction between homotopic brain areas is more intensive than the interaction along the conventional top–down and bottom–up pathways within the brain during unilateral limb movement. The detected strong interhemispheric horizontal functional interaction is an important aspect of motor control but often neglected or underestimated. The strong interhemispheric connectivity may explain the physiological phenomena and effects of promising therapeutic approaches. Further accurate and effective therapeutic methods may be developed on the basis of our findings.

  9. Strong Functional Connectivity among Homotopic Brain Areas Is Vital for Motor Control in Unilateral Limb Movement.

    Science.gov (United States)

    Wei, Pengxu; Zhang, Zuting; Lv, Zeping; Jing, Bin

    2017-01-01

    The mechanism underlying brain region organization for motor control in humans remains poorly understood. In this functional magnetic resonance imaging (fMRI) study, right-handed volunteers were tasked to maintain unilateral foot movements on the right and left sides as consistently as possible. We aimed to identify the similarities and differences between brain motor networks of the two conditions. We recruited 18 right-handed healthy volunteers aged 25 ± 2.3 years and used a whole-body 3T system for magnetic resonance (MR) scanning. Image analysis was performed using SPM8, Conn toolbox and Brain Connectivity Toolbox. We determined a craniocaudally distributed, mirror-symmetrical modular structure. The functional connectivity between homotopic brain areas was generally stronger than the intrahemispheric connections, and such strong connectivity led to the abovementioned modular structure. Our findings indicated that the interhemispheric functional interaction between homotopic brain areas is more intensive than the interaction along the conventional top-down and bottom-up pathways within the brain during unilateral limb movement. The detected strong interhemispheric horizontal functional interaction is an important aspect of motor control but often neglected or underestimated. The strong interhemispheric connectivity may explain the physiological phenomena and effects of promising therapeutic approaches. Further accurate and effective therapeutic methods may be developed on the basis of our findings.

  10. Variation in genes related to cochlear biology is strongly associated with adult-onset deafness in border collies.

    Directory of Open Access Journals (Sweden)

    Jennifer S Yokoyama

    2012-09-01

    Full Text Available Domestic dogs can suffer from hearing losses that can have profound impacts on working ability and quality of life. We have identified a type of adult-onset hearing loss in Border Collies that appears to have a genetic cause, with an earlier age of onset (3-5 years than typically expected for aging dogs (8-10 years. Studying this complex trait within pure breeds of dog may greatly increase our ability to identify genomic regions associated with risk of hearing impairment in dogs and in humans. We performed a genome-wide association study (GWAS to detect loci underlying adult-onset deafness in a sample of 20 affected and 28 control Border Collies. We identified a region on canine chromosome 6 that demonstrates extended support for association surrounding SNP Chr6.25819273 (p-value = 1.09 × 10(-13. To further localize disease-associated variants, targeted next-generation sequencing (NGS of one affected and two unaffected dogs was performed. Through additional validation based on targeted genotyping of additional cases (n = 23 total and controls (n = 101 total and an independent replication cohort of 16 cases and 265 controls, we identified variants in USP31 that were strongly associated with adult-onset deafness in Border Collies, suggesting the involvement of the NF-κB pathway. We found additional support for involvement of RBBP6, which is critical for cochlear development. These findings highlight the utility of GWAS-guided fine-mapping of genetic loci using targeted NGS to study hereditary disorders of the domestic dog that may be analogous to human disorders.

  11. Variation in Genes Related to Cochlear Biology Is Strongly Associated with Adult-Onset Deafness in Border Collies

    Science.gov (United States)

    Ruhe, Alison L.; Erdman, Carolyn A.; Robertson, Kathryn R.; Webb, Aubrey A.; Williams, D. Colette; Chang, Melanie L.; Hytönen, Marjo K.; Lohi, Hannes; Hamilton, Steven P.; Neff, Mark W.

    2012-01-01

    Domestic dogs can suffer from hearing losses that can have profound impacts on working ability and quality of life. We have identified a type of adult-onset hearing loss in Border Collies that appears to have a genetic cause, with an earlier age of onset (3–5 years) than typically expected for aging dogs (8–10 years). Studying this complex trait within pure breeds of dog may greatly increase our ability to identify genomic regions associated with risk of hearing impairment in dogs and in humans. We performed a genome-wide association study (GWAS) to detect loci underlying adult-onset deafness in a sample of 20 affected and 28 control Border Collies. We identified a region on canine chromosome 6 that demonstrates extended support for association surrounding SNP Chr6.25819273 (p-value = 1.09×10−13). To further localize disease-associated variants, targeted next-generation sequencing (NGS) of one affected and two unaffected dogs was performed. Through additional validation based on targeted genotyping of additional cases (n = 23 total) and controls (n = 101 total) and an independent replication cohort of 16 cases and 265 controls, we identified variants in USP31 that were strongly associated with adult-onset deafness in Border Collies, suggesting the involvement of the NF-κB pathway. We found additional support for involvement of RBBP6, which is critical for cochlear development. These findings highlight the utility of GWAS–guided fine-mapping of genetic loci using targeted NGS to study hereditary disorders of the domestic dog that may be analogous to human disorders. PMID:23028339

  12. Quantum correlations responsible for remote state creation: strong and weak control parameters

    Science.gov (United States)

    Doronin, S. I.; Zenchuk, A. I.

    2017-03-01

    We study the quantum correlations between the two remote qubits (sender and receiver) connected by the transmission line (homogeneous spin-1/2 chain) depending on the parameters of the sender's and receiver's initial states (control parameters). We consider two different measures of quantum correlations: the entanglement (a traditional measure) and the informational correlation (based on the parameter exchange between the sender and receiver). We find the domain in the control parameter space yielding (i) zero entanglement between the sender and receiver during the whole evolution period and (ii) non-vanishing informational correlation between the sender and receiver, thus showing that the informational correlation is responsible for the remote state creation. Among the control parameters, there are the strong parameters (which strongly effect the values of studied measures) and the weak ones (whose effect is negligible), therewith the eigenvalues of the initial state are given a privileged role. We also show that the problem of small entanglement (concurrence) in quantum information processing is similar (in certain sense) to the problem of small determinants in linear algebra. A particular model of 40-node spin-1/2 communication line is presented.

  13. Change in CNE boiler control level and stepback to overcome strong grid transients

    International Nuclear Information System (INIS)

    Lorenzetti, J.; Sablic, J.C.

    1991-01-01

    In Argentina the grid distribution is organized in such a way that the Embalse Power Plant is located in a place where power is produced. The most important places of power consumption are located near Buenos Aires city. Just one line connects Embalse with the consumption places. As a result of that condition the power is flowing through the interconnection line in such a way that every time a disturb cuts the line a strong power transient affects the Nuclear Power Plant. The changes in the boiler level control were done in order to avoid reactor trip, reactor stepback or turbine trip based on boiler level upsets. After several years of operation it was possible to verify that the new algorithm reduces the chances of plant outage increasing the confidence in the plant to overcome with success such transient. Every transient in the plant is analyzed in order to improve the control algorithm

  14. Transcription control engineering and applications in synthetic biology

    Directory of Open Access Journals (Sweden)

    Michael D. Engstrom

    2017-09-01

    Full Text Available In synthetic biology, researchers assemble biological components in new ways to produce systems with practical applications. One of these practical applications is control of the flow of genetic information (from nucleic acid to protein, a.k.a. gene regulation. Regulation is critical for optimizing protein (and therefore activity levels and the subsequent levels of metabolites and other cellular properties. The central dogma of molecular biology posits that information flow commences with transcription, and accordingly, regulatory tools targeting transcription have received the most attention in synthetic biology. In this mini-review, we highlight many past successes and summarize the lessons learned in developing tools for controlling transcription. In particular, we focus on engineering studies where promoters and transcription terminators (cis-factors were directly engineered and/or isolated from DNA libraries. We also review several well-characterized transcription regulators (trans-factors, giving examples of how cis- and trans-acting factors have been combined to create digital and analogue switches for regulating transcription in response to various signals. Last, we provide examples of how engineered transcription control systems have been used in metabolic engineering and more complicated genetic circuits. While most of our mini-review focuses on the well-characterized bacterium Escherichia coli, we also provide several examples of the use of transcription control engineering in non-model organisms. Similar approaches have been applied outside the bacterial kingdom indicating that the lessons learned from bacterial studies may be generalized for other organisms.

  15. Transcription control engineering and applications in synthetic biology.

    Science.gov (United States)

    Engstrom, Michael D; Pfleger, Brian F

    2017-09-01

    In synthetic biology, researchers assemble biological components in new ways to produce systems with practical applications. One of these practical applications is control of the flow of genetic information (from nucleic acid to protein), a.k.a. gene regulation. Regulation is critical for optimizing protein (and therefore activity) levels and the subsequent levels of metabolites and other cellular properties. The central dogma of molecular biology posits that information flow commences with transcription, and accordingly, regulatory tools targeting transcription have received the most attention in synthetic biology. In this mini-review, we highlight many past successes and summarize the lessons learned in developing tools for controlling transcription. In particular, we focus on engineering studies where promoters and transcription terminators ( cis -factors) were directly engineered and/or isolated from DNA libraries. We also review several well-characterized transcription regulators ( trans- factors), giving examples of how cis- and trans -acting factors have been combined to create digital and analogue switches for regulating transcription in response to various signals. Last, we provide examples of how engineered transcription control systems have been used in metabolic engineering and more complicated genetic circuits. While most of our mini-review focuses on the well-characterized bacterium Escherichia coli , we also provide several examples of the use of transcription control engineering in non-model organisms. Similar approaches have been applied outside the bacterial kingdom indicating that the lessons learned from bacterial studies may be generalized for other organisms.

  16. Conservation biological control and enemy diversity on a landscape scale

    NARCIS (Netherlands)

    Tscharntke, T.; Bommarco, R.; Clough, Y.; Crist, T.O.; Kleijn, D.; Rand, T.A.; Tylianakis, J.M.; Nouhuys, S.; Vidal, S.

    2007-01-01

    Conservation biological control in agroecosystems requires a landscape management perspective, because most arthropod species experience their habitat at spatial scales beyond the plot level, and there is spillover of natural enemies across the crop–noncrop interface. The species pool in the

  17. Methylene Diphosphonate Chemical and Biological control of MDP complex

    International Nuclear Information System (INIS)

    Aungurarat, Angkanan; Ngamprayad, Tippanan

    2000-01-01

    Technetium-9 9m MDP easy prepared from MDP kits which different sources such as OAP (In house), SIGMA. The resulting Tc 9 9m -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

  18. Biological control agent for mosquito larvae: Review on the killifish ...

    African Journals Online (AJOL)

    This review attempts to give an account on the recent advances on the killifish Aphanius dispar dispar as a biological control agent for mosquito larvae. Thirty six (36) articles of literature (scientific papers, technical and workshop reports) on this subject covering the period between 1980 and 2009 were reviewed.

  19. Studies on bacterial flora and biological control agent of Cydia ...

    African Journals Online (AJOL)

    In the present study, in order to find a more effective and safe biological control agent against Cydia pomonella, we investigated the bacterial flora and tested them for insecticidal effects on this insect. According to morphological, physiological and biochemical tests, bacterial flora were identified as Proteus rettgeri (Cp1), ...

  20. Stakeholder perceptions: Biological control of Russian olive (Elaeagnus angustifolia)

    Science.gov (United States)

    Sharlene E. Sing; Kevin J. Delaney

    2016-01-01

    An online survey was distributed through email lists provided by various stakeholder groups on behalf of the International Consortium for Biological Control of Russian Olive in spring of 2012. A total of 392 respondents replied from 24 U.S. states and 1 Canadian province. Questions posed in the survey were designed to identify and categorize 1) stakeholders by...

  1. The perception of corn farmers about biological control of Caradrina ...

    African Journals Online (AJOL)

    The purpose of this study was to analyze the perception of corn farmers about biological control of Caradrina by Braconid in Dezful Township, Khouzestan Province, Iran. The method used in this study was correlative descriptive and causal relation. A random sample of Dezful township corn farmers of Khouzestan Province, ...

  2. Funding needed for assessments of weed biological control

    Science.gov (United States)

    John L. Maron; Dean E. Pearson; Stephen M. Hovick; Walter P. Carson

    2010-01-01

    Invasive non-native plants are a serious economic and ecological problem worldwide, and major efforts are therefore devoted to reducing weed abundance in agricultural and natural settings. Effective options for reducing invasive abundance and spread are few, although one common approach is biological control - the introduction of specialist herbivores or pathogens from...

  3. Fault Structural Control on Earthquake Strong Ground Motions: The 2008 Wenchuan Earthquake as an Example

    Science.gov (United States)

    Zhang, Yan; Zhang, Dongli; Li, Xiaojun; Huang, Bei; Zheng, Wenjun; Wang, Yuejun

    2018-02-01

    Continental thrust faulting earthquakes pose severe threats to megacities across the world. Recent events show the possible control of fault structures on strong ground motions. The seismogenic structure of the 2008 Wenchuan earthquake is associated with high-angle listric reverse fault zones. Its peak ground accelerations (PGAs) show a prominent feature of fault zone amplification: the values within the 30- to 40-km-wide fault zone block are significantly larger than those on both the hanging wall and the footwall. The PGA values attenuate asymmetrically: they decay much more rapidly in the footwall than in the hanging wall. The hanging wall effects can be seen on both the vertical and horizontal components of the PGAs, with the former significantly more prominent than the latter. All these characteristics can be adequately interpreted by upward extrusion of the high-angle listric reverse fault zone block. Through comparison with a low-angle planar thrust fault associated with the 1999 Chi-Chi earthquake, we conclude that different fault structures might have controlled different patterns of strong ground motion, which should be taken into account in seismic design and construction.

  4. Control and dynamics of attosecond electron wave packets in strong laser fields

    International Nuclear Information System (INIS)

    Johnsson, P.; Remetter, T.; Varju, K.; L'Huillier; Lopez-Martens, R.; Valentin, C.; Balcou, P.; Kazamias, S.; Mauritsson, J.; Gaarde, M.B.; Schafer, K.J.; Mairess, Y.; Wabnitz, H.; Boutu, W.; Salieres, P.

    2005-01-01

    Full text: Trains of attosecond pulses, emerging from the phase-locking of high-order harmonics generated in a strong laser field are now being routinely produced and characterized in a few laser laboratories. Attosecond pulse trains (APTs) are flexible attosecond sources, since the amplitude and relative phase of the spectral components (the harmonics) can be tailored, allowing us to vary both the duration and the carrier frequency of the pulses. Attosecond pulses interacting with a gas of atoms generate electron wave packets (EWPs), which are temporally localized with approximately the same duration as the attosecond pulses. In contrast to the tunneling electron wave packets giving rise to processes such as high-order harmonic generation and above-threshold-ionization (ATI), the properties of these EWPs are inherited from the attosecond pulses through the single-photon ionization step. Thus the energy and temporal characteristics of the EWPs can be varied independently of the process under investigation, by controlling the properties of the attosecond pulses. This talk will describe two recent experiments done in Lund. First we report on the generation, compression and delivery on target of ultrashort extreme-ultraviolet light pulses using external amplitude and phase control. The APT is synthesized from the 13 th to 35 th harmonics of a 35 fs Ti:sapphire laser. The harmonics are generated by focusing the laser beam into a window-less gas cell, filled with argon. To achieve the required on-target attosecond pulses, the harmonics are filtered spatially, using a fixed aperture, and spectrally using aluminum filters. The aluminum filters also serve the purpose of compressing the attosecond pulses, using the negative group-delay dispersion of aluminum to compensate for the intrinsic positive chirp of the attosecond pulses. This experiment demonstrates a practical method for the synthesis and control of attosecond waveforms, and in this case the production of pulses

  5. Biologically controlled minerals as potential indicators of life

    Science.gov (United States)

    Schwartz, D. E.; Mancinelli, R. L.; Kaneshiro, E.

    1991-01-01

    Minerals can be produced and deposited either by abiotic or biologic means. Regardless of their origin, mineral crystals reflect the environment conditions (e.g., temperature, pressure, chemical composition, and redox potential) present during crystal formation. Biologically-produced mineral crystals are grown or reworked under the control of their host organism and reflect an environment different from the abiotic environment. In addition, minerals of either biologic or abiotic origin have great longevities. For these reasons, biologically produced minerals have been proposed as biomarkers. Biomarkers are key morphological, chemical, and isotopic signatures of living systems that can be used to determine if life processes have occurred. Studies of biologically controlled minerals produced by the protist, Paramecium tetraurelia, were initiated since techniques have already been developed to culture them and isolate their crystalline material, and methods are already in place to analyze this material. Two direct crystalline phases were identified. One phase, whose chemical composition is high in Mg, was identified as struvite. The second phase, whose chemical composition is high in Ca, has not been previously found occurring naturally and may be considered a newly discovered material. Analyses are underway to determine the characteristics of these minerals in order to compare them with characteristics of these minerals in order to compare them with characteristics of minerals formed abiotically, but with the same chemical composition.

  6. 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. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  7. Evaluation of Orius species for biological control of Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae)

    NARCIS (Netherlands)

    Tommasini, M.G.

    2003-01-01

    Key words: Thysanoptera, Frankliniella occidentalis, Heteroptera, Orius leavigatu, Orius majusculu, Orius niger, Orius insidiosus, Biology, Diapause, Biological control.The overall aim of this research was to develop a biological control programme for F. occidentalis through the selection of

  8. 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.

  9. Regional amplification of projected changes in extreme temperatures strongly controlled by soil moisture-temperature feedbacks

    Science.gov (United States)

    Vogel, Martha Marie; Orth, René; Cheruy, Frederique; Hagemann, Stefan; Lorenz, Ruth; van den Hurk, Bart; Seneviratne, Sonia Isabelle

    2017-04-01

    Regional hot extremes are projected to increase more strongly than global mean temperature, with substantially larger changes than 2°C even if global warming is limited to this level. We investigate here the role of soil moisture-temperature feedbacks for this response based on multi-model experiments for the 21st century with either interactive or fixed (late 20th century mean seasonal cycle) soil moisture. We analyze changes in the hottest days in each year in both sets of experiments, relate them to the global mean temperature increase, and investigate physical processes leading to these changes. We find that soil moisture-temperature feedbacks significantly contribute to the amplified warming of hottest days compared to that of global mean temperature. This contribution reaches more than 70% in Central Europe and Central North America and between 42%-52% in Amazonia, Northern Australia and Southern Africa. Soil moisture trends (multi-decadal soil moisture variability) are more important for this response than short-term (e.g. seasonal, interannual) soil moisture variability. These results are relevant for reducing uncertainties in regional temperature projections. Vogel, M.M. et al.,2017. Regional amplification of projected changes in extreme temperatures strongly controlled by soil moisture-temperature feedbacks. Geophysical Research Letters, accepted.

  10. Quality controls for wind measurement of a 1290-MHz boundary layer profiler under strong wind conditions.

    Science.gov (United States)

    Liu, Zhao; Zheng, Chaorong; Wu, Yue

    2017-09-01

    Wind profilers have been widely adopted to observe the wind field information in the atmosphere for different purposes. But accuracy of its observation has limitations due to various noises or disturbances and hence need to be further improved. In this paper, the data measured under strong wind conditions, using a 1290-MHz boundary layer profiler (BLP), are quality controlled via a composite quality control (QC) procedure proposed by the authors. Then, through the comparison with the data measured by radiosonde flights (balloon observations), the critical thresholds in the composite QC procedure, including consensus average threshold T 1 and vertical shear threshold T 3 , are systematically discussed. And the performance of the BLP operated under precipitation is also evaluated. It is found that to ensure the high accuracy and high data collectable rate, the optimal range of subsets is determined to be 4 m/s. Although the number of data rejected by the combined algorithm of vertical shear examination and small median test is quite limited, it is proved that the algorithm is quite useful to recognize the outlier with a large discrepancy. And the optimal wind shear threshold T 3 can be recommended as 5 ms -1 /100m. During patchy precipitation, the quality of data measured by the four oblique beams (using the DBS measuring technique) can still be ensured. After the BLP data are quality controlled by the composite QC procedure, the output can show good agreement with the balloon observation.

  11. 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.

  12. Thresholds for HLB vector control in infected commercial citrus and compatibility with biological control

    OpenAIRE

    Monzo, C.; Hendricks, K.; Roberts, P.; Stansly, P. A.

    2014-01-01

    Control of the HLB vector, Diaphorina citri Kuwayama, is considered a basic component for management this disease, even in a high HLB incidence scenario. Such control is mostly chemically oriented. However, over use of insecticides would increase costs and be incompatible with biological control. Establishment of economic thresholds for psyllid control under different price scenarios could optimize returns on investment.

  13. JC polyomavirus infection is strongly controlled by human leucocyte antigen class II variants.

    Directory of Open Access Journals (Sweden)

    Emilie Sundqvist

    2014-04-01

    Full Text Available JC polyomavirus (JCV carriers with a compromised immune system, such as in HIV, or subjects on immune-modulating therapies, such as anti VLA-4 therapy may develop progressive multifocal leukoencephalopathy (PML which is a lytic infection of oligodendrocytes in the brain. Serum antibodies to JCV mark infection occur only in 50-60% of infected individuals, and high JCV-antibody titers seem to increase the risk of developing PML. We here investigated the role of human leukocyte antigen (HLA, instrumental in immune defense in JCV antibody response. Anti-JCV antibody status, as a surrogate for JCV infection, were compared to HLA class I and II alleles in 1621 Scandinavian persons with MS and 1064 population-based Swedish controls and associations were replicated in 718 German persons with MS. HLA-alleles were determined by SNP imputation, sequence specific (SSP kits and a reverse PCR sequence-specific oligonucleotide (PCR-SSO method. An initial GWAS screen displayed a strong HLA class II region signal. The HLA-DRB1*15 haplotype was strongly negatively associated to JCV sero-status in Scandinavian MS cases (OR = 0.42, p = 7×10(-15 and controls (OR = 0.53, p = 2×10(-5. In contrast, the DQB1*06:03 haplotype was positively associated with JCV sero-status, in Scandinavian MS cases (OR = 1.63, p = 0.006, and controls (OR = 2.69, p = 1×10(-5. The German dataset confirmed these findings (OR = 0.54, p = 1×10(-4 and OR = 1.58, p = 0.03 respectively for these haplotypes. HLA class II restricted immune responses, and hence CD4+ T cell immunity is pivotal for JCV infection control. Alleles within the HLA-DR1*15 haplotype are associated with a protective effect on JCV infection. Alleles within the DQB1*06:03 haplotype show an opposite association. These associations between JC virus antibody response and human leucocyte antigens supports the notion that CD4+ T cells are crucial in the immune defence to JCV and

  14. Quality control of X-ray irradiator by biological markers

    International Nuclear Information System (INIS)

    Miura, Miwa; Lukmanul Hakkim, F.; Yoshida, Masahiro; Matsuda, Naoki; Morita, Naoko

    2011-01-01

    The exposure of animals or cultured cells to radiation is the essential and common step in experimental researches to elucidate biological effects of radiation. When an X-ray generator is used as a radiation source, physical parameters including dose, dose rate, and the energy spectrum of X-ray play crucial roles in biological outcome. Therefore, those parameters are the important points to be checked in quality control and to be carefully considered in advance to the irradiation to obtain the accurate and reproductive results. Here we measured radiation dose emitted from the X-ray irradiator for research purposes by using clonogenic survival of cultured mammalian cells as a biological marker in parallel with physical dosimetry. The results drawn from both methods exhibited good consistency in the dose distribution on the irradiation stage. Furthermore, the close relationship was observed between cell survival and the photon energy spectrum by using different filter components. These results suggest that biological dosimetry is applicable to quality control of X-ray irradiator in adjunct to physical dosimetry and that it possibly helps better understanding of the optimal irradiating condition by X-ray users in life-science field. (author)

  15. Design control considerations for biologic-device combination products.

    Science.gov (United States)

    Anderson, Dave; Liu, Roger; Anand Subramony, J; Cammack, Jon

    2017-03-01

    Combination products are therapeutic and diagnostic medical products that combine drugs, devices, and/or biological products with one another. Historically, biologics development involved identifying efficacious doses administered to patients intravenously or perhaps by a syringe. Until fairly recently, there has been limited focus on developing an accompanying medical device, such as a prefilled syringe or auto-injector, to enable easy and more efficient delivery. For the last several years, and looking forward, where there may be little to distinguish biologics medicines with relatively similar efficacy profiles, the biotechnology market is beginning to differentiate products by patient-focused, biologic-device based combination products. As innovative as biologic-device combination products are, they can pose considerable development, regulatory, and commercialization challenges due to unique physicochemical properties and special clinical considerations (e.g., dosing volumes, frequency, co-medications, etc.) of the biologic medicine. A biologic-device combination product is a marriage between two partners with "cultural differences," so to speak. There are clear differences in the development, review, and commercialization processes of the biologic and the device. When these two cultures come together in a combination product, developers and reviewers must find ways to address the design controls and risk management processes of both the biologic and device, and knit them into a single entity with supporting product approval documentation. Moreover, digital medicine and connected health trends are pushing the boundaries of combination product development and regulations even further. Despite an admirable cooperation between industry and FDA in recent years, unique product configurations and design features have resulted in review challenges. These challenges have prompted agency reviewers to modernize consultation processes, while at the same time, promoting

  16. Controlled polymer synthesis--from biomimicry towards synthetic biology.

    Science.gov (United States)

    Pasparakis, George; Krasnogor, Natalio; Cronin, Leroy; Davis, Benjamin G; Alexander, Cameron

    2010-01-01

    The controlled assembly of synthetic polymer structures is now possible with an unprecedented range of functional groups and molecular architectures. In this critical review we consider how the ability to create artificial materials over lengthscales ranging from a few nm to several microns is generating systems that not only begin to mimic those in nature but also may lead to exciting applications in synthetic biology (139 references).

  17. Assessing Probabilistic Risk Assessment Approaches for Insect Biological Control Introductions

    OpenAIRE

    Kaufman, Leyla V.; Wright, Mark G.

    2017-01-01

    The introduction of biological control agents to new environments requires host specificity tests to estimate potential non-target impacts of a prospective agent. Currently, the approach is conservative, and is based on physiological host ranges determined under captive rearing conditions, without consideration for ecological factors that may influence realized host range. We use historical data and current field data from introduced parasitoids that attack an endemic Lepidoptera species in H...

  18. Hybridization of an invasive shrub affects tolerance and resistance to defoliation by a biological control agent

    Science.gov (United States)

    Williams, Wyatt I.; Friedman, Jonathan M.; Gaskin, John F.; Norton, Andrew P.

    2014-01-01

    Evolution has contributed to the successful invasion of exotic plant species in their introduced ranges, but how evolution affects particular control strategies is still under evaluation. For instance, classical biological control, a common strategy involving the utilization of highly specific natural enemies to control exotic pests, may be negatively affected by host hybridization because of shifts in plant traits, such as root allocation or chemical constituents. We investigated introgression between two parent species of the invasive shrub tamarisk (Tamarix spp.) in the western United States, and how differences in plant traits affect interactions with a biological control agent. Introgression varied strongly with latitude of origin and was highly correlated with plant performance. Increased levels of T. ramosissima introgression resulted in both higher investment in roots and tolerance to defoliation and less resistance to insect attack. Because tamarisk hybridization occurs predictably on the western U.S. landscape, managers may be able to exploit this information to maximize control efforts. Genetic differentiation in plant traits in this system underpins the importance of plant hybridization and may explain why some biological control releases are more successful than others.

  19. Biocrust spatial distribution at landscape scale is strongly controlled by terrain attributes: Topographic thresholds for colonization

    Science.gov (United States)

    Raúl Román Fernández, José; Rodríguez-Caballero, Emilio; Chamizo de la Piedra, Sonia; Roncero Ramos, Bea; Cantón Castilla, Yolanda

    2017-04-01

    Biological soil crusts (biocrusts) are spatially variable components of soil. Whereas biogeographic, climatic or soil properties drive biocrust distribution from regional to global scales, biocrust spatial distribution within the landscape is controlled by topographic forces that create specific microhabitats that promote or difficult biocrust growth. By knowing which are the variables that control biocrust distribution and their individual effect we can establish the abiotic thresholds that limit natural biocrust colonization on different environments, which may be very useful for designing soil restoration programmes. The objective of this study was to analyse the influence of topographic-related variables in the distribution of different types of biocrust within a semiarid catchment where cyanobacteria and lichen dominated biocrust represent the most important surface components, El Cautivo experimental area (SE Spain). To do this, natural coverage of i) bare soil, ii) vegetation, iii) cyanobacteria-dominated soil crust and iv) lichen-dominated soil crust were measured on 70 experimental plots distributed across 23 transect (three 4.5 x 4.5 m plots per transect). Following that, we used a 1m x 1m DEM (Digital Elevation Model) of the study site obtained from a LiDAR point cloud to calculate different topographic variables such as slope gradient, length slope (LS) factor (potential sediment transport index), potential incoming solar radiation, topographic wetness index (WI) and maximum flow accumulation. Canonical Correspondence Analysis was performed to infer the influence of each variable in the coverage of each class and thresholds of biocrust colonization were identified mathematically by means of linear regression analysis describing the relationship between each factor and biocrust cover. Our results show that the spatial distribution of cyanobacteria-dominated biocrust, which showed physiological and morphological adaptation to cope with drought and UVA

  20. Biologically-Inspired Control Architecture for Musical Performance Robots

    Directory of Open Access Journals (Sweden)

    Jorge Solis

    2014-10-01

    Full Text Available At Waseda University, since 1990, the authors have been developing anthropomorphic musical performance robots as a means for understanding human control, introducing novel ways of interaction between musical partners and robots, and proposing applications for humanoid robots. In this paper, the design of a biologically-inspired control architecture for both an anthropomorphic flutist robot and a saxophone playing robot are described. As for the flutist robot, the authors have focused on implementing an auditory feedback system to improve the calibration procedure for the robot in order to play all the notes correctly during a performance. In particular, the proposed auditory feedback system is composed of three main modules: an Expressive Music Generator, a Feed Forward Air Pressure Control System and a Pitch Evaluation System. As for the saxophone-playing robot, a pressure-pitch controller (based on the feedback error learning to improve the sound produced by the robot during a musical performance was proposed and implemented. In both cases studied, a set of experiments are described to verify the improvements achieved while considering biologically-inspired control approaches.

  1. 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

  2. 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.

  3. 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.

  4. 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. © 2016 The Author(s).

  5. 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

  6. 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

  7. 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

  8. Biological control of fruit flies (Diptera: Tephritidae) through parasitoid augmentative releases: Current status

    International Nuclear Information System (INIS)

    Montoya, Pablo; Liedo, Pablo

    2000-01-01

    Fruit flies are among the main pests affecting the world fruit industry (Aluja 1993). Bait sprays have traditionally been used successfully to control them; however, the side effects on the environment and health hazards commonly associated with pesticides, have resulted in strong public opposition to the use of bait sprays. This is particularly so when sprays are applied in urban areas or in coffee plantations where, although Medflies are present, they do not pose a danger to crops. Alternative methods that are effective and environmental friendly to suppress fruit fly populations are highly desirable. Biological control, the use of natural enemies to suppress pest populations, represents such an alternative. Some of the most successful cases of biological control are the control of Iceria purchasi Maskell (Homoptera: Margarodidae) by Rodolia cardinalis Mulsant (Coleoptera: Coccinellidae) in California (De Bach 1968, van den Bosch et al. 1982), and the control of Aleurocanthus woglumi Ashby (Homoptera: Aleyrodidae) mainly by Encarsia (=Prospaltella) opulenta Silv. (Hymenoptera: Aphelinidae) in Mexico (Jimenez 1961, 1971), both using the classical approach. However, this approach has been limited to certain conditions of environmental stability and biodiversity which are only found in a few ecosystems. Other factors, such as types of pests, the economic threshold and product quality requirements represent additional limitations. The best option in many cases could be augmentative biological control, which could overcome some of the deficiencies of the classical approach (Sivinski 1996). According to Knipling (1992) and Barclay (1987), augmentative biological control can be considered as a formal alternative for suppressing pest populations and even for use in eradication programmes, after integration with the sterile insect technique (SIT). In this approach, mass production of natural enemies is required and this production has to be cost effective

  9. Multiple levels of epigenetic control for bone biology and pathology.

    Science.gov (United States)

    Montecino, Martin; Stein, Gary; Stein, Janet; Zaidi, Kaleem; Aguilar, Rodrigo

    2015-12-01

    Multiple dimensions of epigenetic control contribute to regulation of gene expression that governs bone biology and pathology. Once confined to DNA methylation and a limited number of post-translational modifications of histone proteins, the definition of epigenetic mechanisms is expanding to include contributions of non-coding RNAs and mitotic bookmarking, a mechanism for retaining phenotype identity during cell proliferation. Together these different levels of epigenetic control of physiological processes and their perturbations that are associated with compromised gene expression during the onset and progression of disease, have contributed to an unprecedented understanding of the activities (operation) of the genomic landscape. Here, we address general concepts that explain the contribution of epigenetic control to the dynamic regulation of gene expression during eukaryotic transcription. This article is part of a Special Issue entitled Epigenetics and Bone. Copyright © 2015 Elsevier Inc. All rights reserved.

  10. A Biomechanical Comparison of Proportional Electromyography Control to Biological Torque Control Using a Powered Hip Exoskeleton

    Directory of Open Access Journals (Sweden)

    Aaron J. Young

    2017-06-01

    Full Text Available BackgroundDespite a large increase in robotic exoskeleton research, there are few studies that have examined human performance with different control strategies on the same exoskeleton device. Direct comparison studies are needed to determine how users respond to different types of control. The purpose of this study was to compare user performance using a robotic hip exoskeleton with two different controllers: a controller that targeted a biological hip torque profile and a proportional myoelectric controller.MethodsWe tested both control approaches on 10 able-bodied subjects using a pneumatically powered hip exoskeleton. The state machine controller targeted a biological hip torque profile. The myoelectric controller used electromyography (EMG of lower limb muscles to produce a proportional control signal for the hip exoskeleton. Each subject performed two 30-min exoskeleton walking trials (1.0 m/s using each controller and a 10-min trial with the exoskeleton unpowered. During each trial, we measured subjects’ metabolic cost of walking, lower limb EMG profiles, and joint kinematics and kinetics (torques and powers using a force treadmill and motion capture.ResultsCompared to unassisted walking in the exoskeleton, myoelectric control significantly reduced metabolic cost by 13% (p = 0.005 and biological hip torque control reduced metabolic cost by 7% (p = 0.261. Subjects reduced muscle activity relative to the unpowered condition for a greater number of lower limb muscles using myoelectric control compared to the biological hip torque control. More subjects subjectively preferred the myoelectric controller to the biological hip torque control.ConclusionMyoelectric control had more advantages (metabolic cost and muscle activity reduction compared to a controller that targeted a biological torque profile for walking with a robotic hip exoskeleton. However, these results were obtained with a single exoskeleton device with specific

  11. A Biomechanical Comparison of Proportional Electromyography Control to Biological Torque Control Using a Powered Hip Exoskeleton.

    Science.gov (United States)

    Young, Aaron J; Gannon, Hannah; Ferris, Daniel P

    2017-01-01

    Despite a large increase in robotic exoskeleton research, there are few studies that have examined human performance with different control strategies on the same exoskeleton device. Direct comparison studies are needed to determine how users respond to different types of control. The purpose of this study was to compare user performance using a robotic hip exoskeleton with two different controllers: a controller that targeted a biological hip torque profile and a proportional myoelectric controller. We tested both control approaches on 10 able-bodied subjects using a pneumatically powered hip exoskeleton. The state machine controller targeted a biological hip torque profile. The myoelectric controller used electromyography (EMG) of lower limb muscles to produce a proportional control signal for the hip exoskeleton. Each subject performed two 30-min exoskeleton walking trials (1.0 m/s) using each controller and a 10-min trial with the exoskeleton unpowered. During each trial, we measured subjects' metabolic cost of walking, lower limb EMG profiles, and joint kinematics and kinetics (torques and powers) using a force treadmill and motion capture. Compared to unassisted walking in the exoskeleton, myoelectric control significantly reduced metabolic cost by 13% ( p  = 0.005) and biological hip torque control reduced metabolic cost by 7% ( p  = 0.261). Subjects reduced muscle activity relative to the unpowered condition for a greater number of lower limb muscles using myoelectric control compared to the biological hip torque control. More subjects subjectively preferred the myoelectric controller to the biological hip torque control. Myoelectric control had more advantages (metabolic cost and muscle activity reduction) compared to a controller that targeted a biological torque profile for walking with a robotic hip exoskeleton. However, these results were obtained with a single exoskeleton device with specific control configurations while level walking at a

  12. Biological Efficacy of Herbicides for Weed Control in Noncropped Areas

    Directory of Open Access Journals (Sweden)

    Tsvetanka Dimitrova

    2009-01-01

    Full Text Available An increasing problem facing agricultural producers is the invasion of weeds, perennial in particular, so that implementation of industrial technologies is impossible without their highly efficient and rational control. For the purpose of studying efficient herbicides for weed control in noncropped areas (stubbles, a biological study of five total systemic herbicides was conducted in areas under natural weed infestation and pressure from othersurrounding weeds at the Institute of Forage Crops in Pleven in 2005-2007. The trials were carried out in field conditions using the block method with plot size of 20 m². Treatment was conducted at the predominant stage of budding of perennial dicotyledonous weeds and earing of monocotyledonous weeds. Herbicidal efficacy was recorded on the EWRS 9-score scale (0-100% killed weeds = score 9-1. It was found that treatment of noncropped areas (stubbles with the total systemic herbicides Touchdown System 4 (360 g/l glyphosate; Cosmic (360 g/l glyphosate; Roundup Plus (441 g/l glyphosate potassium salt; Leon 36 SL (360 g/l glyphosate and Glyphos Super 45 SL (450 g/l glyphosate was highly efficient, so that it was a successful element of a strategy for controlling weeds of different biological groups, and was especially effective against perennial weeds.

  13. Control of the cassava mealybug in Africa: lessons from a biological ...

    African Journals Online (AJOL)

    Control of the cassava mealybug in Africa: lessons from a biological control project. ... Such studies are needed in order to attribute the observed effects to various causes and to advance the science of biological control. ( 4) It is concluded that biological control is the basis ofiPM but cannot usually be manipulated by the ...

  14. 75 FR 64984 - Availability of an Environmental Assessment for a Biological Control Agent for Hawkweeds

    Science.gov (United States)

    2010-10-21

    ... hawkweed gall wasp, Aulacidea subterminalis, into the continental United States as a biological control... United States for the biological control of hawkweeds (Hieracium pilosella, H. aurantiacum, H... control, and the use of biological control organisms. The use of herbicides, while effective, is limited...

  15. Using biological control research in the classroom to promote scientific inquiry and literacy

    Science.gov (United States)

    Many scientists who research biological control also teach at universities or more informally through cooperative outreach. The purpose of this paper is to review biological control activities for the classroom in four refereed journals, The American Biology Teacher, Journal of Biological Education...

  16. Asymmetric positive feedback loops reliably control biological responses.

    Science.gov (United States)

    Ratushny, Alexander V; Saleem, Ramsey A; Sitko, Katherine; Ramsey, Stephen A; Aitchison, John D

    2012-04-24

    Positive feedback is a common mechanism enabling biological systems to respond to stimuli in a switch-like manner. Such systems are often characterized by the requisite formation of a heterodimer where only one of the pair is subject to feedback. This ASymmetric Self-UpREgulation (ASSURE) motif is central to many biological systems, including cholesterol homeostasis (LXRα/RXRα), adipocyte differentiation (PPARγ/RXRα), development and differentiation (RAR/RXR), myogenesis (MyoD/E12) and cellular antiviral defense (IRF3/IRF7). To understand why this motif is so prevalent, we examined its properties in an evolutionarily conserved transcriptional regulatory network in yeast (Oaf1p/Pip2p). We demonstrate that the asymmetry in positive feedback confers a competitive advantage and allows the system to robustly increase its responsiveness while precisely tuning the response to a consistent level in the presence of varying stimuli. This study reveals evolutionary advantages for the ASSURE motif, and mechanisms for control, that are relevant to pharmacologic intervention and synthetic biology applications.

  17. Biologically inspired autonomous structural materials with controlled toughening and healing

    Science.gov (United States)

    Garcia, Michael E.; Sodano, Henry A.

    2010-04-01

    The field of structural health monitoring (SHM) has made significant contributions in the field of prognosis and damage detection in the past decade. The advantageous use of this technology has not been integrated into operational structures to prevent damage from propagating or to heal injured regions under real time loading conditions. Rather, current systems relay this information to a central processor or human operator, who then determines a course of action such as altering the mission or scheduling repair maintenance. Biological systems exhibit advanced sensory and healing traits that can be applied to the design of material systems. For instance, bone is the major structural component in vertebrates; however, unlike modern structural materials, bone has many properties that make it effective for arresting the propagation of cracks and subsequent healing of the fractured area. The foremost goal for the development of future adaptive structures is to mimic biological systems, similar to bone, such that the material system can detect damage and deploy defensive traits to impede damage from propagating, thus preventing catastrophic failure while in operation. After sensing and stalling the propagation of damage, the structure must then be repaired autonomously using self healing mechanisms motivated by biological systems. Here a novel autonomous system is developed using shape memory polymers (SMPs), that employs an optical fiber network as both a damage detection sensor and a network to deliver stimulus to the damage site initiating adaptation and healing. In the presence of damage the fiber optic fractures allowing a high power laser diode to deposit a controlled level of thermal energy at the fractured sight locally reducing the modulus and blunting the crack tip, which significantly slows the crack growth rate. By applying a pre-induced strain field and utilizing the shape memory recovery effect, thermal energy can be deployed to close the crack and return

  18. High-throughput SHAPE analysis reveals structures in HIV-1 genomic RNA strongly conserved across distinct biological states.

    Directory of Open Access Journals (Sweden)

    Kevin A Wilkinson

    2008-04-01

    Full Text Available Replication and pathogenesis of the human immunodeficiency virus (HIV is tightly linked to the structure of its RNA genome, but genome structure in infectious virions is poorly understood. We invent high-throughput SHAPE (selective 2'-hydroxyl acylation analyzed by primer extension technology, which uses many of the same tools as DNA sequencing, to quantify RNA backbone flexibility at single-nucleotide resolution and from which robust structural information can be immediately derived. We analyze the structure of HIV-1 genomic RNA in four biologically instructive states, including the authentic viral genome inside native particles. Remarkably, given the large number of plausible local structures, the first 10% of the HIV-1 genome exists in a single, predominant conformation in all four states. We also discover that noncoding regions functioning in a regulatory role have significantly lower (p-value < 0.0001 SHAPE reactivities, and hence more structure, than do viral coding regions that function as the template for protein synthesis. By directly monitoring protein binding inside virions, we identify the RNA recognition motif for the viral nucleocapsid protein. Seven structurally homologous binding sites occur in a well-defined domain in the genome, consistent with a role in directing specific packaging of genomic RNA into nascent virions. In addition, we identify two distinct motifs that are targets for the duplex destabilizing activity of this same protein. The nucleocapsid protein destabilizes local HIV-1 RNA structure in ways likely to facilitate initial movement both of the retroviral reverse transcriptase from its tRNA primer and of the ribosome in coding regions. Each of the three nucleocapsid interaction motifs falls in a specific genome domain, indicating that local protein interactions can be organized by the long-range architecture of an RNA. High-throughput SHAPE reveals a comprehensive view of HIV-1 RNA genome structure, and further

  19. Complete Call-by-Value Calculi of Control Operators II: Strong Termination

    OpenAIRE

    Hasegawa, Ryu

    2017-01-01

    We provide characterization of the strong termination property of the CCV lambda-mu calculus introduced in the first part of the series of the paper. The calculus is complete with respect to the standard CPS semantics. The union-intersection type systems for the calculus is developed in the previous paper. We characterize the strong normalizability of terms of the calculus in terms of the CPS semantics and typeability.

  20. Biological forcing controls the chemistry of the coral exoskeleton

    Science.gov (United States)

    Meibom, A.; Mostefaoui, S.; Cuif, J.; Yurimoto, H.; Dauphin, Y.; Houlbreque, F.; Dunbar, R.; Constantz, B.

    2006-12-01

    A multitude of marine organisms produce calcium carbonate skeletons that are used extensively to reconstruct water temperature variability of the tropical and subtropical oceans - a key parameter in global climate-change models. Such paleo-climate reconstructions are based on the notion that skeletal oxygen isotopic composition and certain trace-element abundances (e.g., Sr/Ca and Mg/Ca ratios) vary in response to changes in the water temperature. However, it is a fundamental problem that poorly understood biological processes introduce large compositional deviations from thermodynamic equilibrium and hinder precise calibrations of many paleo-climate proxies. Indeed, the role of water temperature in controlling the composition of the skeleton is far from understood. We have studied trace-element abundances as well as oxygen and carbon isotopic compositions of individual skeletal components in the zooxanthellate and non-zooxanthellate corals at ultra-structural, i.e. micrometer to sub-micrometer length scales. From this body of work we draw the following, generalized conclusions: 1) Centers of calcification (COC) are not in equilibrium with seawater. Notably, the Sr/Ca ratio is higher than expected for aragonite equilibrium with seawater at the temperature at which the skeleton was formed. Furthermore, the COC are further away from equilibrium with seawater than fibrous skeleton in terms of stable isotope composition. 2) COC are dramatically different from the fibrous aragonite skeleton in terms of trace element composition. 3) Neither trace element nor stable isotope variations in the fibrous (bulk) part of the skeleton are directly related to changes in SST. In fact, changes in SST can have very little to do with the observed compositional variations. 4) Trace element variations in the fibrous (bulk) part of the skeleton are not related to the activity of zooxanthellae. These observations are directly relevant to the issue of biological versus non-biological

  1. Silver Nanoshell Plasmonically Controlled Emission of Semiconductor Quantum Dots in the Strong Coupling Regime.

    Science.gov (United States)

    Zhou, Ning; Yuan, Meng; Gao, Yuhan; Li, Dongsheng; Yang, Deren

    2016-04-26

    Strong coupling between semiconductor excitons and localized surface plasmons (LSPs) giving rise to hybridized plexciton states in which energy is coherently and reversibly exchanged between the components is vital, especially in the area of quantum information processing from fundamental and practical points of view. Here, in photoluminescence spectra, rather than from common extinction or reflection measurements, we report on the direct observation of Rabi splitting of approximately 160 meV as an indication of strong coupling between excited states of CdSe/ZnS quantum dots (QDs) and LSP modes of silver nanoshells under nonresonant nanosecond pulsed laser excitation at room temperature. The strong coupling manifests itself as an anticrossing-like behavior of the two newly formed polaritons when tuning the silver nanoshell plasmon energies across the exciton line of the QDs. Further analysis substantiates the essentiality of high pump energy and collective strong coupling of many QDs with the radiative dipole mode of the metallic nanoparticles for the realization of strong coupling. Our finding opens up interesting directions for the investigation of strong coupling between LSPs and excitons from the perspective of radiative recombination under easily accessible experimental conditions.

  2. Biological Characteristics and Control of Orobanche Crenata Forsk., a Review

    Directory of Open Access Journals (Sweden)

    Alessia Restuccia

    2009-03-01

    Full Text Available Orobanche crenata is a holoparasitic phanerogam which is particularly noxious to legumes, such as faba bean (Vicia faba L., pea (Pisum sativum L., chickpea (Cicer arietinum L., lentil (Lens culinaris Medik., etc., and commonly considered one of the major causes which has contributed to re-rizing the area designed to their cultivation. After a few brief references on the origin and diffusion of O. crenata, in this work summarises the results of research into biological aspects and control of this species. The information obtained especially concerns seed production, seed viability, seed longevity and dormancy, seed conditioning and germination, parasitism phases, the effects of parasite attacks on host plants and the means of control.

  3. Entomopatogenic fungi as an alternative for biological pest control

    Directory of Open Access Journals (Sweden)

    Pablo Andrés Motta Delgado

    2011-08-01

    Full Text Available The entomopatogenic fungi are a diverse group of microorganisms that provide multiple services to agroecological systems. Among those the capacity to regulate the pests to keep them in suitable levels stands out. The present paper shows a description of the entomopatogenic fungi of most extensively used for the biological control of pests, their mechanism of action on their host, and also investigations about the in vitro and in situ behavior of the mostly used fungi for the control of some insects. Also, the formulations that are used for the development of this biotechnology in the field are described. In the development of bioinsecticides the entomopatogenic fungi are a viable option to minimize environmental damage.

  4. Biological Characteristics and Control of Orobanche Crenata Forsk., a Review

    Directory of Open Access Journals (Sweden)

    Giuseppe Restuccia

    2011-02-01

    Full Text Available Orobanche crenata is a holoparasitic phanerogam which is particularly noxious to legumes, such as faba bean (Vicia faba L., pea (Pisum sativum L., chickpea (Cicer arietinum L., lentil (Lens culinaris Medik., etc., and commonly considered one of the major causes which has contributed to re-rizing the area designed to their cultivation. After a few brief references on the origin and diffusion of O. crenata, in this work summarises the results of research into biological aspects and control of this species. The information obtained especially concerns seed production, seed viability, seed longevity and dormancy, seed conditioning and germination, parasitism phases, the effects of parasite attacks on host plants and the means of control.

  5. Assessing Probabilistic Risk Assessment Approaches for Insect Biological Control Introductions.

    Science.gov (United States)

    Kaufman, Leyla V; Wright, Mark G

    2017-07-07

    The introduction of biological control agents to new environments requires host specificity tests to estimate potential non-target impacts of a prospective agent. Currently, the approach is conservative, and is based on physiological host ranges determined under captive rearing conditions, without consideration for ecological factors that may influence realized host range. We use historical data and current field data from introduced parasitoids that attack an endemic Lepidoptera species in Hawaii to validate a probabilistic risk assessment (PRA) procedure for non-target impacts. We use data on known host range and habitat use in the place of origin of the parasitoids to determine whether contemporary levels of non-target parasitism could have been predicted using PRA. Our results show that reasonable predictions of potential non-target impacts may be made if comprehensive data are available from places of origin of biological control agents, but scant data produce poor predictions. Using apparent mortality data rather than marginal attack rate estimates in PRA resulted in over-estimates of predicted non-target impact. Incorporating ecological data into PRA models improved the predictive power of the risk assessments.

  6. 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.

  7. Reevaluation of the value of autoparasitoids in biological control.

    Directory of Open Access Journals (Sweden)

    Lian-Sheng Zang

    Full Text Available Autoparasitoids with the capacity of consuming primary parasitoids that share the same hosts to produce males are analogous to intraguild predators. The use of autoparasitoids in biological control programs is a controversial matter because there is little evidence to support the view that autoparasitoids do not disrupt and at times may promote suppression of insect pests in combination with primary parasitoids. We found that Encarsia sophia, a facultative autoparasitoid, preferred to use heterospecific hosts as secondary hosts for producing males. The autoparasitoids mated with males originated from heterospecifics may parasitize more hosts than those mated with males from conspecifics. Provided with an adequate number of males, the autoparasitoids killed more hosts than En. formosa, a commonly used parasitoid for biological control of whiteflies. This study supports the view that autoparasitoids in combination with primary parasitoids do not disrupt pest management and may enhance such programs. The demonstrated preference of an autoparasitoid for heterospecifics and improved performance of males from heterospecifics observed in this study suggests these criteria should be considered in strategies that endeavor to mass-produce and utilize autoparasitoids in the future.

  8. Assessing Probabilistic Risk Assessment Approaches for Insect Biological Control Introductions

    Directory of Open Access Journals (Sweden)

    Leyla V. Kaufman

    2017-07-01

    Full Text Available The introduction of biological control agents to new environments requires host specificity tests to estimate potential non-target impacts of a prospective agent. Currently, the approach is conservative, and is based on physiological host ranges determined under captive rearing conditions, without consideration for ecological factors that may influence realized host range. We use historical data and current field data from introduced parasitoids that attack an endemic Lepidoptera species in Hawaii to validate a probabilistic risk assessment (PRA procedure for non-target impacts. We use data on known host range and habitat use in the place of origin of the parasitoids to determine whether contemporary levels of non-target parasitism could have been predicted using PRA. Our results show that reasonable predictions of potential non-target impacts may be made if comprehensive data are available from places of origin of biological control agents, but scant data produce poor predictions. Using apparent mortality data rather than marginal attack rate estimates in PRA resulted in over-estimates of predicted non-target impact. Incorporating ecological data into PRA models improved the predictive power of the risk assessments.

  9. Augmenting Plant Immune Responses and Biological Control by Microbial Determinants

    Directory of Open Access Journals (Sweden)

    Sang Moo Lee

    2015-09-01

    Full Text Available Plant have developed sophisticated defence mechanisms against microbial pathogens. The recent accumulated information allow us to understand the nature of plant immune responses followed by recognition of microbial factors/determinants through cutting-edge genomics and multi-omics techniques. However, the practical approaches to sustain plant health using enhancement of plant immunity is yet to be fully appreciated. Here, we overviewed the general concept and representative examples on the plant immunity. The fungal, bacterial, and viral determinants that was previously reported as the triggers of plant immune responses are introduced and described as the potential protocol of biological control. Specifically, the role of chitin, glucan, lipopolysaccharides/extracellular polysaccharides, microbe/pathogen-associated molecular pattern, antibiotics, mimic-phytohormones, N-acyl homoserine lactone, harpin, vitamins, and volatile organic compounds are considered. We hope that this review stimulates scientific community and farmers to broaden their knowledge on the microbial determinant-based biological control and to apply the technology on the integrated pest management program.

  10. The small hive beetle Aethina tumida: A review of its biology and control measures

    Directory of Open Access Journals (Sweden)

    Andrew G. S. CUTHBERTSON et al

    2013-10-01

    Full Text Available The small hive beetle Aethina tumida is an endemic parasitic pest and scavenger of colonies of social bees indigenous to sub-Saharan Africa. In this region this species rarely inflicts severe damage on strong colonies since the bees have develo­­ped strategies to combat them. However, A. tumida has since ‘escaped’ from its native home and has recently invaded areas such as North America and Australia where its economic impact on the apiculture industry has been significant. Small hive beetle, should it become established within Europe, represents a real and live threat to the UK bee keeping industry. Here we review the biology and current pest status of A. tumida and up to-date research in terms of both chemical and biological control used against this honey bee pest [Current Zoology 59 (5: 644–653, 2013].

  11. Social and economic factors for the adoption of biological control of ...

    African Journals Online (AJOL)

    The results also showed that the decision on the application of biological control is determined by the educational level, income, mechanization level, extension activities, biological control awareness, social participation, attitude toward biological control and access to information sources which have significant influence.

  12. 77 FR 46373 - Availability of an Environmental Assessment for a Biological Control Agent for Hemlock Woolly...

    Science.gov (United States)

    2012-08-03

    ...] Availability of an Environmental Assessment for a Biological Control Agent for Hemlock Woolly Adelgid AGENCY... States for use as a biological control agent to reduce the severity of hemlock woolly adelgid... beetle from the western United States, into the eastern United States for use as a biological control...

  13. 75 FR 28232 - Availability of an Environmental Assessment for a Biological Control Agent for Hemlock Woolly...

    Science.gov (United States)

    2010-05-20

    ...] Availability of an Environmental Assessment for a Biological Control Agent for Hemlock Woolly Adelgid AGENCY..., into the continental United States for use as a biological control agent to reduce the severity of... biological control agent to reduce the severity of hemlock woolly adelgid (HWA) infestations. HWA, an...

  14. 75 FR 69396 - Availability of an Environmental Assessment for a Biological Control Agent for Arundo donax

    Science.gov (United States)

    2010-11-12

    ... Biological Control Agent for Arundo donax AGENCY: Animal and Plant Health Inspection Service, USDA. ACTION... alternatives to, the release of Arundo scale into the continental United States for use as a biological control... a biological control agent to reduce the severity of Arundo donax infestations. A. donax is a highly...

  15. Optical Control of Mechanical Mode-Coupling within a MoS2 Resonator in the Strong-Coupling Regime.

    Science.gov (United States)

    Liu, Chang-Hua; Kim, In Soo; Lauhon, Lincoln J

    2015-10-14

    Two-dimensional (2-D) materials including graphene and transition metal dichalcogenides (TMDs) are an exciting platform for ultrasensitive force and displacement detection in which the strong light-matter coupling is exploited in the optical control of nanomechanical motion. Here we report the optical excitation and displacement detection of a ∼ 3 nm thick MoS2 resonator in the strong-coupling regime, which has not previously been achieved in 2-D materials. Mechanical mode frequencies can be tuned by more than 12% by optical heating, and they exhibit avoided crossings indicative of strong intermode coupling. When the membrane is optically excited at the frequency difference between vibrational modes, normal mode splitting is observed, and the intermode energy exchange rate exceeds the mode decay rate by a factor of 15. Finite element and analytical modeling quantifies the extent of mode softening necessary to control intermode energy exchange in the strong coupling regime.

  16. BIOMASS PRODUCTION AND FORMULATION OF Bacillus subtilis FOR BIOLOGICAL CONTROL

    Directory of Open Access Journals (Sweden)

    Amran Muis

    2016-10-01

    Full Text Available Bacillus subtilis is a widespread bacterium found in soil, water, and air. It controls the growth of certain harmful bacteria and fungi, presumably by competing for nutrients, growth sites on plants, and by directly colonizing and attaching to fungal pathogens. When applied to seeds, it colonizes the developing root system of the plants and continues to live on the root system and provides protection throughout the growing season. The study on biomass production and formulation of B. subtilis for biological control was conducted in the laboratory of Department of Plant Pathology, College of Agriculture, University of the Philippines Los Baños (UPLB-CA, College, Laguna from May to July 2005. The objective of the study was to determine the optimum pH and a good carbon source for biomass production of B. subtilis and to develop a seed treatment formulation of B. subtilis as biological control agent. Results showed that the optimum pH for growth of B. subtilis was pH 6 (1.85 x 109 cfu/ml. In laboratory tests for biomass production using cassava flour, corn flour, rice flour, and brown sugar as carbon sources, it grew best in brown sugar plus yeast extract medium (6.8 x 108 cfu ml-1 in sterile distilled water and 7.8 x 108 cfu ml-1 in coconut water. In test for bacterial biomass carriers, talc proved to be the best in terms of number of bacteria recovered from the seeds (3.98 x 105 cfu seed-1.

  17. Models for integrated pest control and their biological implications.

    Science.gov (United States)

    Tang, Sanyi; Cheke, Robert A

    2008-09-01

    Successful integrated pest management (IPM) control programmes depend on many factors which include host-parasitoid ratios, starting densities, timings of parasitoid releases, dosages and timings of insecticide applications and levels of host-feeding and parasitism. Mathematical models can help us to clarify and predict the effects of such factors on the stability of host-parasitoid systems, which we illustrate here by extending the classical continuous and discrete host-parasitoid models to include an IPM control programme. The results indicate that one of three control methods can maintain the host level below the economic threshold (ET) in relation to different ET levels, initial densities of host and parasitoid populations and host-parasitoid ratios. The effects of host intrinsic growth rate and parasitoid searching efficiency on host mean outbreak period can be calculated numerically from the models presented. The instantaneous pest killing rate of an insecticide application is also estimated from the models. The results imply that the modelling methods described can help in the design of appropriate control strategies and assist management decision-making. The results also indicate that a high initial density of parasitoids (such as in inundative releases) and high parasitoid inter-generational survival rates will lead to more frequent host outbreaks and, therefore, greater economic damage. The biological implications of this counter intuitive result are discussed.

  18. Controlling the alignment of neutral molecules by a strong laser field

    DEFF Research Database (Denmark)

    Sakai, H.; Hilligsøe, Karen Marie; Hald, K.

    1999-01-01

    by lowering the initial rotational energy of the molecules or by increasing the laser intensity. The alignment is measured by photodissociating the molecules with a femtosecond laser pulse and detecting the direction of the photofragments by imaging techniques. The strongest degree of alignment observed......A strong nonresonant nanosecond laser pulse is used to align neutral iodine molecules. The technique, applicable to both polar and nonpolar molecules, relies on the interaction between the strong laser field and the induced dipole moment of the molecules. The degree of alignment is enhanced...

  19. Biology and life history of Argopistes tsekooni (Coleoptera: Chrysomelidae) in China, a promising biological control agent of Chinese privet.

    Science.gov (United States)

    Y-Z Zhang; J. Sun; J.L. Hanula

    2009-01-01

    The biology and life history of Argopistes tsekooni Chen (Coleoptera: Chrysomelidae), a potential biological control agent of Chinese privet, Ligustrum sinense Lour., was studied under laboratory and outdoor conditions in Huangshan City of Anhui Province, China, in 2006. A. tsekooni larvae are leafminers that...

  20. Can Flowering Greencover Crops Promote Biological Control in German Vineyards?

    Directory of Open Access Journals (Sweden)

    Christoph Hoffmann

    2017-11-01

    Full Text Available Greencover crops are widely recommended to provide predators and parasitoids with floral resources for improved pest control. We studied parasitism and predation of European grapevine moth (Lobesia botrana eggs and pupae as well as predatory mite abundances in an experimental vineyard with either one or two sowings of greencover crops compared to spontaneous vegetation. The co-occurrence between greencover flowering time and parasitoid activity differed greatly between the two study years. Parasitism was much higher when flowering and parasitoid activity coincided. While egg predation was enhanced by greencover crops, there were no significant benefits of greencover crops on parasitism of L. botrana eggs or pupae. Predatory mites did not show an as strong increase on grapevines in greencover crop plots as egg predation. Overall, our study demonstrates only limited pest control benefits of greencover crops. Given the strong within- and between year variation in natural enemy activity, studies across multiple years will be necessary to adequately describe the role of greencover crops for pest management and to identify the main predators of L. botrana eggs.

  1. Using strong nonlinearity and high-frequency vibrations to control effective properties of discrete elastic waveguides

    DEFF Research Database (Denmark)

    Lazarov, Boyan Stefanov; Thomsen, Jon Juel; Snaeland, Sveinn Orri

    2008-01-01

    The aim of this article is to investigate how highfrequency (HF) excitation, combined with strong nonlinear elastic material behavior, influences the effective material or structural properties for low-frequency excitation and wave propagation. The HF effects are demonstrated on discrete linear s...

  2. Rearing and Release of Megamelus scutellaris Berg (Hemiptera: Delphacidae) for Biological Control of Water hyacinth in 2015

    Science.gov (United States)

    2017-06-01

    Hemiptera: Delphacidae) for Biological Control of Waterhyacinth in 2015 by Jan Freedman and Nathan Harms PURPOSE: Waterhyacinth biological control ... control agents. Three insects were released in the United States for biological control of waterhyacinth during the 1970s; two weevils, Neochetina...content) and competitive interactions with other biological control agents (e.g., Neochetina spp.), though their consideration in other biological

  3. Interferon Lambda Genetics and Biology in Regulation of Viral Control

    Directory of Open Access Journals (Sweden)

    Emily A. Hemann

    2017-12-01

    Full Text Available Type III interferons, also known as interferon lambdas (IFNλs, are the most recent addition to the IFN family following their discovery in 2003. Initially, IFNλ was demonstrated to induce expression of interferon-stimulated genes and exert antiviral properties in a similar manner to type I IFNs. However, while IFNλ has been described to have largely overlapping expression and function with type I IFNs, it has become increasingly clear that type III IFNs also have distinct functions from type I IFNs. In contrast to type I IFNs, whose receptor is ubiquitously expressed, type III IFNs signal and function largely at barrier epithelial surfaces, such as the respiratory and gastrointestinal tracts, as well as the blood–brain barrier. In further support of unique functions for type III IFNs, single nucleotide polymorphisms in IFNL genes in humans are strongly associated with outcomes to viral infection. These biological linkages have also been more directly supported by studies in mice highlighting roles of IFNλ in promoting antiviral immune responses. In this review, we discuss the current understanding of type III IFNs, and how their functions are similar to, and different from, type I IFN in various immune cell subtypes and viral infections.

  4. Quagga and zebra mussels: biology, impacts, and control

    Science.gov (United States)

    Nalepa, Thomas F.; Schloesser, Don W.; Nalepa, Thomas F.; Schloesser, Don W.

    2013-01-01

    Quagga and Zebra Mussels: Biology, Impacts, and Control, Second Edition provides a broad view of the zebra/quagga mussel issue, offering a historic perspective and up-to-date information on mussel research. Comprising 48 chapters, this second edition includes reviews of mussel morphology, physiology, and behavior. It details mussel distribution and spread in Europe and across North America, and examines policy and regulatory responses, management strategies, and mitigation efforts. In addition, this book provides extensive coverage of the impact of invasive mussel species on freshwater ecosystems, including effects on water clarity, phytoplankton, water quality, food web changes, and consequences to other aquatic fauna. It also reviews and offers new insights on how zebra and quagga mussels respond and adapt to varying environmental conditions. This new edition includes seven video clips that complement chapter text and, through visual documentation, provide a greater understanding of mussel behavior and distribution.

  5. Strong Broadband Terahertz Optical Activity through Control of the Blaschke Phase with Chiral Metasurfaces

    Science.gov (United States)

    Cole, Michael A.; Chen, Wen-chen; Liu, Mingkai; Kruk, Sergey S.; Padilla, Willie J.; Shadrivov, Ilya V.; Powell, David A.

    2017-07-01

    We demonstrate terahertz chiral metamaterials that achieve resonant transmission and strong optical activity. This response is realized in a metasurface coupled to its Babinet complement, with additional twist. Uniquely, the optical activity achieved in this type of metamaterial is weakly dispersive around the resonant transmission maxima, but it can be highly dispersive around the transmission minima. It has recently been shown that this unique optical activity response is closely related to zeros in the transmission spectra of circular polarizations through the Kramers-Kronig relations and strong resonant features in the optical activity spectrum corresponding to the Blaschke phase terms. Here we demonstrate how modifying the meta-atom geometry greatly affects the location and magnitude of these Blaschke phase terms. We study three different meta-atoms, which are variations on the simple cross structure. Their responses are measured using terahertz time-domain spectroscopy and analyzed via numerical simulations.

  6. Electrical control of spontaneous emission and strong coupling for a single quantum dot

    DEFF Research Database (Denmark)

    Laucht, A.; Hofbauer, F.; Hauke, N.

    2009-01-01

    We report the design, fabrication and optical investigation of electrically tunable single quantum dots—photonic crystal defect nanocavities operating in both the weak and strong coupling regimes of the light–matter interaction. Unlike previous studies where the dot–cavity spectral detuning...... switchable optical nonlinearity at the single photon level, paving the way towards on-chip dot-based nano-photonic devices that can be integrated with passive optical components....

  7. A note on the strong formulation of stochastic control problems with model uncertainty

    OpenAIRE

    Sirbu, Mihai

    2014-01-01

    We consider a  Markovian stochastic control problem with  model uncertainty. The controller (intelligent player) observes only the state, and, therefore, uses feedback (closed-loop) strategies.  The adverse player (nature) who does not have a direct interest in the payoff, chooses open-loop controls that parametrize Knightian uncertainty. This creates a two-step optimization  problem (like half of a game) over feedback strategies and open-loop controls. The main result is to sh...

  8. Economic value of biological control in integrated pest management of managed plant systems.

    Science.gov (United States)

    Naranjo, Steven E; Ellsworth, Peter C; Frisvold, George B

    2015-01-07

    Biological control is an underlying pillar of integrated pest management, yet little focus has been placed on assigning economic value to this key ecosystem service. Setting biological control on a firm economic foundation would help to broaden its utility and adoption for sustainable crop protection. Here we discuss approaches and methods available for valuation of biological control of arthropod pests by arthropod natural enemies and summarize economic evaluations in classical, augmentative, and conservation biological control. Emphasis is placed on valuation of conservation biological control, which has received little attention. We identify some of the challenges of and opportunities for applying economics to biological control to advance integrated pest management. Interaction among diverse scientists and stakeholders will be required to measure the direct and indirect costs and benefits of biological control that will allow farmers and others to internalize the benefits that incentivize and accelerate adoption for private and public good.

  9. 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

  10. An Insight in the Reproductive Biology of Therophilus javanus (Hymenoptera, Braconidae, and Agathidinae, a Potential Biological Control Agent against the Legume Pod Borer (Lepidoptera, Crambidae

    Directory of Open Access Journals (Sweden)

    Djibril Aboubakar Souna

    2017-01-01

    Full Text Available Therophilus javanus is a koinobiont, solitary larval endoparasitoid currently being considered as a biological control agent against the pod borer Maruca vitrata, a devastating cowpea pest causing 20–80% crop losses in West Africa. We investigated ovary morphology and anatomy, oogenesis, potential fecundity, and egg load in T. javanus, as well as the effect of factors such as age of the female and parasitoid/host size at oviposition on egg load. The number of ovarioles was found to be variable and significantly influenced by the age/size of the M. vitrata caterpillar when parasitized. Egg load also was strongly influenced by both the instar of M. vitrata caterpillar at the moment of parasitism and wasp age. The practical implications of these findings for improving mass rearing of the parasitoid toward successful biological control of M. vitrata are discussed.

  11. 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.

  12. Using strong nonlinearity and high-frequency vibrations to control effective mechanical stiffness

    DEFF Research Database (Denmark)

    Thomsen, Jon Juel

    2008-01-01

    the method of direct separation of motions with results of a modified multiple scales ap-proach, valid also for strong nonlinearity, the stiffening ef-fect is predicted for a generic 1-dof system, and results are tested against numerical simulation and ((it is planned)) laboratory experiments.......High-frequency excitation (HFE) can be used to change the effective stiffness of an elastic structure, and related quanti-ties such as resonance frequencies, wave speed, buckling loads, and equilibrium states. There are basically two ways to do this: By using parametrical HFE (with or without non...

  13. Thyrotropin-releasing hormone controls mitochondrial biology in human epidermis.

    Science.gov (United States)

    Knuever, Jana; Poeggeler, Burkhard; Gáspár, Erzsébet; Klinger, Matthias; Hellwig-Burgel, Thomas; Hardenbicker, Celine; Tóth, Balázs I; Bíró, Tamás; Paus, Ralf

    2012-03-01

    Mitochondrial capacity and metabolic potential are under the control of hormones, such as thyroid hormones. The most proximal regulator of the hypothalamic-pituitary-thyroid (HPT) axis, TRH, is the key hypothalamic integrator of energy metabolism via its impact on thyroid hormone secretion. Here, we asked whether TRH directly modulates mitochondrial functions in normal, TRH-receptor-positive human epidermis. Organ-cultured human skin was treated with TRH (5-100 ng/ml) for 12-48 h. TRH significantly increased epidermal immunoreactivity for the mitochondria-selective subunit I of respiratory chain complex IV (MTCO1). This resulted from an increased MTCO1 transcription and protein synthesis and a stimulation of mitochondrial biogenesis as demonstrated by transmission electron microscopy and TRH-enhanced mitochondrial DNA synthesis. TRH also significantly stimulated the transcription of several other mitochondrial key genes (TFAM, HSP60, and BMAL1), including the master regulator of mitochondrial biogenesis (PGC-1α). TRH significantly enhanced mitochondrial complex I and IV enzyme activity and enhanced the oxygen consumption of human skin samples, which shows that the stimulated mitochondria are fully vital because the main source for cellular oxygen consumption is mitochondrial endoxidation. These findings identify TRH as a potent, novel neuroendocrine stimulator of mitochondrial activity and biogenesis in human epidermal keratinocytes in situ. Thus, human epidermis offers an excellent model for dissecting neuroendocrine controls of human mitochondrial biology under physiologically relevant conditions and for exploring corresponding clinical applications.

  14. Using Biological-Control Research in the Classroom to Promote Scientific Inquiry & Literacy

    Science.gov (United States)

    Richardson, Matthew L.; Richardson, Scott L.; Hall, David G.

    2012-01-01

    Scientists researching biological control should engage in education because translating research programs into classroom activities is a pathway to increase scientific literacy among students. Classroom activities focused on biological control target all levels of biological organization and can be cross-disciplinary by drawing from subject areas…

  15. Strong supramolecular control over protein self-assembly using a polyamine decorated β-cyclodextrin as synthetic recognition element

    NARCIS (Netherlands)

    Uhlenheuer, D.A.; Milroy, L.G.; Neirynck, P.; Brunsveld, L.

    2011-01-01

    The supramolecular host molecule heptakis-[6-deoxy-6-(2-aminoethylsulfanyl)]-ß-cyclodextrin provides strong control over protein self-assembly in synthetic supramolecular protein constructs. Mono-functionalization of this modified ß-cyclodextrin with a cysteine residue allows for site-selective

  16. Biology, diversity and strategies for the monitoring and control of triatomines--Chagas disease vectors.

    Science.gov (United States)

    Costa, Jane; Lorenzo, Marcelo

    2009-07-01

    Despite the relevant achievements in the control of the main Chagas disease vectors Triatoma infestans and Rhodnius prolixus, several factors still promote the risk of infection. The disease is a real threat to the poor rural regions of several countries in Latin America. The current situation in Brazil requires renewed attention due to its high diversity of triatomine species and to the rapid and drastic environmental changes that are occurring. Using the biology, behaviour and diversity of triatomines as a basis for new strategies for monitoring and controlling the vectorial transmission are discussed here. The importance of ongoing long-term monitoring activities for house infestations by T. infestans, Triatoma brasiliensis, Panstrongylus megistus, Triatoma rubrovaria and R. prolixus is also stressed, as well as understanding the invasion by sylvatic species. Moreover, the insecticide resistance is analysed. Strong efforts to sustain and improve surveillance procedures are crucial, especially when the vectorial transmission is considered interrupted in many endemic areas.

  17. BIOLOGICAL CONTROL - AS A MEANS TO CONTROL INSECT PESTS IN AZERBAIJAN

    Directory of Open Access Journals (Sweden)

    Z. M. Mamedov

    2013-01-01

    Full Text Available Two hundreds and twenty species parasites and predators of pests of various agricultures are revealed in Azerbaijan. The complex of entomophages of certain pests of agricultures is studied: 48 species of parasites and predators of Chloridea obsoleta 21 species of entomophages of Pectinophora malvella Hb., over 160 species of entomophages of pests of ozehards and vegetables, 34 species of entomophages of pests of forests. The hundreds species of entomophages and some entomophogenous microbes and antagonists are revealed. Biology and ecology of over 60 species of entomophages and useful microorganisims which are prospective as biological control agents are studied.

  18. Control of discrete linear repetitive processes using strong practical stability and H_infinity disturbance attenuation

    Czech Academy of Sciences Publication Activity Database

    Dabkowski, Pavel; Galkowski, K.; Bachelier, O.; Rogers, E.

    2012-01-01

    Roč. 61, č. 12 (2012), s. 1138-1144 ISSN 0167-6911 R&D Projects: GA MŠk(CZ) 1M0567 Institutional research plan: CEZ:AV0Z10750506 Keywords : 2-D systems control * Disturbance attenuation Subject RIV: BC - Control Systems Theory Impact factor: 1.667, year: 2012 http://library.utia.cas.cz/separaty/2012/TR/dabkowski-0383031.pdf

  19. Regional amplification of projected changes in extreme temperatures strongly controlled by soil moisture-temperature feedbacks

    Science.gov (United States)

    Vogel, M. M.; Orth, R.; Cheruy, F.; Hagemann, S.; Lorenz, R.; Hurk, B. J. J. M.; Seneviratne, S. I.

    2017-02-01

    Regional hot extremes are projected to increase more strongly than global mean temperature, with substantially larger changes than 2°C even if global warming is limited to this level. We investigate the role of soil moisture-temperature feedbacks for this response based on multimodel experiments for the 21st century with either interactive or fixed (late 20th century mean seasonal cycle) soil moisture. We analyze changes in the hottest days in each year in both sets of experiments, relate them to the global mean temperature increase, and investigate processes leading to these changes. We find that soil moisture-temperature feedbacks significantly contribute to the amplified warming of the hottest days compared to that of global mean temperature. This contribution reaches more than 70% in Central Europe and Central North America. Soil moisture trends are more important for this response than short-term soil moisture variability. These results are relevant for reducing uncertainties in regional temperature projections.

  20. Controlled self-assembly of multiferroic core-shell nanoparticles exhibiting strong magneto-electric effects

    Energy Technology Data Exchange (ETDEWEB)

    Sreenivasulu, Gollapudi; Hamilton, Sean L.; Lehto, Piper R.; Srinivasan, Gopalan, E-mail: srinivas@oakland.edu [Physics Department, Oakland University, Rochester, Michigan 48309-4401 (United States); Popov, Maksym [Physics Department, Oakland University, Rochester, Michigan 48309-4401 (United States); Radiophysics Department, Taras Shevchenko National University of Kyiv, Kyiv 01601 (Ukraine); Chavez, Ferman A. [Chemistry Department, Oakland University, Rochester, Michigan 48309-4401 (United States)

    2014-02-03

    Ferromagnetic-ferroelectric composites show strain mediated coupling between the magnetic and electric sub-systems due to magnetostriction and piezoelectric effects associated with the ferroic phases. We have synthesized core-shell multiferroic nano-composites by functionalizing 10–100 nm barium titanate and nickel ferrite nanoparticles with complementary coupling groups and allowing them to self-assemble in the presence of a catalyst. The core-shell structure was confirmed by electron microscopy and magnetic force microscopy. Evidence for strong strain mediated magneto-electric coupling was obtained by static magnetic field induced variations in the permittivity over 16–18 GHz and polarization and by electric field induced by low-frequency ac magnetic fields.

  1. Transition from weak to strong measurements by nonlinear quantum feedback control

    International Nuclear Information System (INIS)

    Zhang Jing; Liu Yuxi; Wu Rebing; Li Chunwen; Tarn, Tzyh-Jong

    2010-01-01

    We find that feedback control may induce 'pseudo'-nonlinear dynamics in a damped harmonic oscillator, whose centroid trajectory in the phase space behaves like a classical nonlinear system. Thus, similar to nonlinear amplifiers (e.g., rf-driven Josephson junctions), feedback control on the harmonic oscillator can induce nonlinear bifurcation, which can be used to amplify small signals and further to measure quantum states of qubits. Using the cavity QED and the circuit QED systems as examples, we show how to apply our method to measuring the states of two-level atoms and superconducting charge qubits.

  2. How strongly does appetite counter weight loss? Quantification of the feedback control of human energy intake

    Science.gov (United States)

    Polidori, David; Sanghvi, Arjun; Seeley, Randy; Hall, Kevin D.

    2016-01-01

    Objective To quantify the feedback control of energy intake in response to long-term covert manipulation of energy balance in free-living humans. Methods We used a validated mathematical method to calculate energy intake changes during a 52 week placebo-controlled trial in 153 patients treated with canagliflozin, a sodium glucose co-transporter inhibitor that increases urinary glucose excretion thereby resulting in weight loss without patients being directly aware of the energy deficit. We analyzed the relationship between the body weight time course and the calculated energy intake changes using principles from engineering control theory. Results We discovered that weight loss leads to a proportional increase in appetite resulting in eating above baseline by ~100 kcal/day per kg of lost weight – an amount more than 3-fold larger than the corresponding energy expenditure adaptations. Conclusions While energy expenditure adaptations are often thought to be the main reason for slowing of weight loss and subsequent regain, feedback control of energy intake plays an even larger role and helps explain why long-term maintenance of a reduced body weight is so difficult. PMID:27804272

  3. Implications of Plasmodium vivax Biology for Control, Elimination, and Research

    Science.gov (United States)

    Olliaro, Piero L.; Barnwell, John W.; Barry, Alyssa; Mendis, Kamini; Mueller, Ivo; Reeder, John C.; Shanks, G. Dennis; Snounou, Georges; Wongsrichanalai, Chansuda

    2016-01-01

    This paper summarizes our current understanding of the biology of Plasmodium vivax, how it differs from Plasmodium falciparum, and how these differences explain the need for P. vivax-tailored interventions. The article further pinpoints knowledge gaps where investments in research are needed to help identify and develop such specific interventions. The principal obstacles to reduce and eventually eliminate P. vivax reside in 1) its higher vectorial capacity compared with P. falciparum due to its ability to develop at lower temperature and over a shorter sporogonic cycle in the vector, allowing transmission in temperate zones and making it less sensitive to vector control measures that are otherwise effective on P. falciparum; 2) the presence of dormant liver forms (hypnozoites), sustaining multiple relapsing episodes from a single infectious bite that cannot be diagnosed and are not susceptible to any available antimalarial except primaquine, with routine deployment restricted by toxicity; 3) low parasite densities, which are difficult to detect with current diagnostics leading to missed diagnoses and delayed treatments (and protracted transmission), coupled with 4) transmission stages (gametocytes) occurring early in acute infections, before infection is diagnosed. PMID:27799636

  4. Biological control of alien and invasive species in agriculture

    International Nuclear Information System (INIS)

    Calvitti, Maurizio; Moretti Riccardo; Lampazzi, Elena

    2015-01-01

    Agricultural production in Europe faces many challenges including limited availability of water, nitrogen input and fossil fuels. It is necessary, therefore, to identify methods of production and new technologies to increase the efficiency of the primary systems, guaranteeing amount of food, quality, safety and eco-sustainability . One of the most important aspects, though often undervalued in relation to the food chain, is the adversity of biological management of agricultural crops due to pests, pathogens or fitomizi with potential invasive already present in the territory or of recent origin alien. In this context, two main objectives should be implemented at the same time reduce production losses and protect the agro-ecosystem. To meet these expectations, as of January 1, 2015 all farms in the European Union countries are bound to the application of the Integrated Defense principles, as indicated by the Directive on the sustainable use of plant protection products (128/09 / EC) .In response to this and other new entomological emergencies plant health and medical-veterinary entomologist researchers of the Laboratory sustainable management of Agro-Ecosystems in ENEA, have directed their research towards the development of innovative systems for the sustainable control of invasive species of insects is in the agricultural sector that health. [it

  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. Synthesis, chemical and biological quality control of radioiodinated peptides

    International Nuclear Information System (INIS)

    Rafii, H.; Khalaj, A.; Beiki, D.; Motameidi, F.; Maloobi, M.; Karimian-dehghan, M.; Keshavarrzi, F.

    2002-01-01

    Iodinated compounds with I-131, 125 and 123 have been widely used for biochemical function studies. In conjunction with SPECT, [I-123] labelled proteins have various diagnostic and therapeutic applications in nuclear medicine. Preparation of some radioiodinated peptides with tyrosine and/or lysine groups on their main chain molecules can be carried out with both direct and indirect methods, but lack of these groups in molecule cause the molecule dose not lend itself for direct radioiodination. In this study, human IgG and Formyl-Methyl-Leucyl-Phenylalanine, FMLF, have been chosen as a model compounds for direct and indirect radioiodination respectively. Here, we will describe the labelling procedure of [I-125] IgG using chloramine-T as a suitable oxidant agent and [I-125 and I-131] FMLF by indirect method using ATE/SIB as a prosthetic group in multi-step reactions. The obtained results for chemical quality control of intermediate radioiodinated SIB by HPLC and two labelled IgG and FMLF will be also discussed. Biological results, biodistribution studies and SPECT scans on mice per-injected labelled FMLF show a low uptake of thyroid but a high at urine and bladder, perhaps because of low molecular weight of FMLF. In this case, it seems to be better to separate the reaction mixture of labelled FMLF by BPLC than Sephadex-G50 gel filtration. (Author)

  7. Implications of Plasmodium vivax Biology for Control, Elimination, and Research.

    Science.gov (United States)

    Olliaro, Piero L; Barnwell, John W; Barry, Alyssa; Mendis, Kamini; Mueller, Ivo; Reeder, John C; Shanks, G Dennis; Snounou, Georges; Wongsrichanalai, Chansuda

    2016-12-28

    This paper summarizes our current understanding of the biology of Plasmodium vivax, how it differs from Plasmodium falciparum, and how these differences explain the need for P. vivax-tailored interventions. The article further pinpoints knowledge gaps where investments in research are needed to help identify and develop such specific interventions. The principal obstacles to reduce and eventually eliminate P. vivax reside in 1) its higher vectorial capacity compared with P. falciparum due to its ability to develop at lower temperature and over a shorter sporogonic cycle in the vector, allowing transmission in temperate zones and making it less sensitive to vector control measures that are otherwise effective on P. falciparum; 2) the presence of dormant liver forms (hypnozoites), sustaining multiple relapsing episodes from a single infectious bite that cannot be diagnosed and are not susceptible to any available antimalarial except primaquine, with routine deployment restricted by toxicity; 3) low parasite densities, which are difficult to detect with current diagnostics leading to missed diagnoses and delayed treatments (and protracted transmission), coupled with 4) transmission stages (gametocytes) occurring early in acute infections, before infection is diagnosed. © The American Society of Tropical Medicine and Hygiene.

  8. Linearity of bulk-controlled inverter ring VCO in weak and strong inversion

    DEFF Research Database (Denmark)

    Wismar, Ulrik Sørensen; Wisland, D.; Andreani, Pietro

    2007-01-01

    In this paper linearity of frequency modulation in voltage controlled inverter ring oscillators for non feedback sigma delta converter applications is studied. The linearity is studied through theoretical models of the oscillator operating at supply voltages above and below the threshold voltage......, process variations and temperature variations have also been simulated to indicate the advantages of having the soft rail bias transistor in the VCO....

  9. Active Control of Power Exhaust in Strongly Heated ASDEX Upgrade Plasmas

    Science.gov (United States)

    Dux, Ralph; Kallenbach, Arne; Bernert, Matthias; Eich, Thomas; Fuchs, Christoph; Giannone, Louis; Herrmann, Albrecht; Schweinzer, Josef; Treutterer, Wolfgang

    2012-10-01

    Due to the absence of carbon as an intrinsic low-Z radiator, and tight limits for the acceptable power load on the divertor target, ITER will rely on impurity seeding for radiative power dissipation and for generation of partial detachment. The injection of more than one radiating species is required to optimise the power removal in the main plasma and in the divertor region, i.e. a low-Z species for radiation in the divertor and a medium-Z species for radiation in the outer core plasma. In ASDEX Upgrade, a set of robust sensors, which is suitable to feedback control the radiated power in the main chamber and the divertor as well as the electron temperature at the target, has been developed. Different feedback schemes were applied in H-mode discharges with a maximum heating power of up to 23,W, i.e. at ITER values of P/R (power per major radius) to control all combinations of power flux into the divertor region, power flux onto the target or electron temperature at the target through injection of nitrogen as the divertor radiator and argon as the main chamber radiator. Even at the highest heating powers the peak heat flux density at the target is kept at benign values. The control schemes and the plasma behaviour in these discharges will be discussed.

  10. Electrical Control of Structural and Physical Properties via Strong Spin-Orbit Interactions in Sr2IrO4

    Science.gov (United States)

    Cao, G.; Terzic, J.; Zhao, H. D.; Zheng, H.; De Long, L. E.; Riseborough, Peter S.

    2018-01-01

    Electrical control of structural and physical properties is a long-sought, but elusive goal of contemporary science and technology. We demonstrate that a combination of strong spin-orbit interactions (SOI) and a canted antiferromagnetic Mott state is sufficient to attain that goal. The antiferromagnetic insulator Sr2IrO4 provides a model system in which strong SOI lock canted Ir magnetic moments to IrO6 octahedra, causing them to rigidly rotate together. A novel coupling between an applied electrical current and the canting angle reduces the Néel temperature and drives a large, nonlinear lattice expansion that closely tracks the magnetization, increases the electron mobility, and precipitates a unique resistive switching effect. Our observations open new avenues for understanding fundamental physics driven by strong SOI in condensed matter, and provide a new paradigm for functional materials and devices.

  11. Synthetic biology and regulatory networks: where metabolic systems biology meets control engineering

    NARCIS (Netherlands)

    He, F.; Murabito, E.; Westerhoff, H.V.

    2016-01-01

    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 throughin silicotheoretical studies with the aim to guide and complement furtherin vitroandin vivoexperimental

  12. Pythium species and isolate diversity influence inhibition by the biological control agent Streptomyces lydicus

    Science.gov (United States)

    Disease control of soilborne pathogens by biological control agents has often been inconsistent under field conditions. One factor that may contribute to this inconsistency is the variability in response among pathogen populations and/or communities to the selected biological control agent. One hund...

  13. 76 FR 3076 - Availability of an Environmental Assessment for a Biological Control Agent for Air Potato

    Science.gov (United States)

    2011-01-19

    ...] Availability of an Environmental Assessment for a Biological Control Agent for Air Potato AGENCY: Animal and... environmental assessment (EA) relative to the control of air potato (Dioscorea bulbifera). The EA considers the... States for use as a biological control agent to reduce the severity of air potato infestations. We are...

  14. Augmentative biological control in the Mexican national fruit fly campaign

    Energy Technology Data Exchange (ETDEWEB)

    Montoya, P [Campana Nacional Moscas de la Fruta, DGSV-SAGARPA (Mexico); Cancino, J; Gutierrez, J M; Santiago, G [Campana Nacional Moscas de la Fruta, DGSV-SAGARPA (Mexico)

    2005-07-01

    Full text: Tephritid fruit flies are some of the most economically important species of insects worldwide. In Mexico, the native Anastrepha ludens, A. obliqua, A. serpentina and A. striata, are among the most important problems because of the great number of commercial fruits they attack. In an attempt to solve the Anastrepha fruit flies problems, the Mexican Government created the National Campaign against Fruit Flies in 1992. Using an area-wide approach and an integrated pest management framework, that included the use of environment-friendly strategies to suppress/eradicate fruit flies, the Mexican Campaign has integrated different technologies such as the application of specific toxic bait, the use of the Sterile Insect Technique (SIT), and the release of the endoparasitoid Diachasmimorpha longicaudata (Ashmead) (Hymenoptera: Braconidae), which attacks preferably third instar larvae of fruit flies. Since 1995, the Moscafrut mass-rearing facility has the capacity to produce an average of 50 millions of parasitised pupae per week, with 65-70% of parasitoid emergence using irradiated A. ludens larvae as host. The mass-rearing procedures of D. longicaudata have been fully described by Cancino. Parasitised pupae are sent via commercial flights to several states of the country (i.e. Michoacan, Sinaloa, Nayarit, Tamaulipas), according to a yearly national plan. This plan derives from industry requirements and/or availability of biological material. In the target zones, parasitoids are released in specific periods and specific areas where the environmental, biological and social conditions are considered as adequate. Packing and release procedures of parasitoids follow those that Montoya et al used. The releases are focused on Anastrepha spp. host trees located in marginal areas (i.e backyard orchards), with the objective to prevent the migration of fruit fly populations into commercial orchards. The impact of parasitoids on fruit fly populations is evaluated through

  15. Patterns and controls on nitrogen cycling of biological soil crusts

    Science.gov (United States)

    Barger, Nichole N.; Zaady, Eli; Weber, Bettina; Garcia-Pichel, Ferran; Belnap, Jayne

    2016-01-01

    Biocrusts play a significant role in the nitrogen [N ] cycle within arid and semi-arid ecosystems, as they contribute major N inputs via biological fixation and dust capture, harbor internal N transformation processes, and direct N losses via N dissolved, gaseous and erosional loss processes (Fig. 1). Because soil N availability in arid and semi-arid ecosystems is generally low and may limit net primary production (NPP), especially during periods when adequate water is available, understanding the mechanisms and controls of N input and loss pathways in biocrusts is critically important to our broader understanding of N cycling in dryland environments. In particular, N cycling by biocrusts likely regulates short-term soil N availability to support vascular plant growth, as well as long-term N accumulation and maintenance of soil fertility. In this chapter, we review the influence of biocrust nutrient input, internal cycling, and loss pathways across a range of biomes. We examine linkages between N fixation capabilities of biocrust organisms and spatio-temporal patterns of soil N availability that may influence the longer-term productivity of dryland ecosystems. Lastly, biocrust influence on N loss pathways such as N gas loss, leakage of N compounds from biocrusts, and transfer in wind and water erosion are important to understand the maintenance of dryland soil fertility over longer time scales. Although great strides have been made in understanding the influence of biocrusts on ecosystem N cycling, there are important knowledge gaps in our understanding of the influence of biocrusts on ecosystem N cycling that should be the focus of future studies. Because work on the interaction of N cycling and biocrusts was reviewed in Belnap and Lange (2003), this chapter will focus primarily on research findings that have emerged over the last 15 years (2000-2015).

  16. Air pollution control and decreasing new particle formation lead to strong climate warming

    Directory of Open Access Journals (Sweden)

    R. Makkonen

    2012-02-01

    Full Text Available The number concentration of cloud droplets determines several climatically relevant cloud properties. A major cause for the high uncertainty in the indirect aerosol forcing is the availability of cloud condensation nuclei (CCN, which in turn is highly sensitive to atmospheric new particle formation. Here we present the effect of new particle formation on anthropogenic aerosol forcing in present-day (year 2000 and future (year 2100 conditions. The present-day total aerosol forcing is increased from −1.0 W m−2 to −1.6 W m−2 when nucleation is introduced into the model. Nucleation doubles the change in aerosol forcing between years 2000 and 2100, from +0.6 W m−2 to +1.4 W m−2. Two climate feedbacks are studied, resulting in additional negative forcings of −0.1 W m−2 (+10% DMS emissions in year 2100 and −0.5 W m−2 (+50% BVOC emissions in year 2100. With the total aerosol forcing diminishing in response to air pollution control measures taking effect, warming from increased greenhouse gas concentrations can potentially increase at a very rapid rate.

  17. Air pollution control and decreasing new particle formation lead to strong climate warming

    Science.gov (United States)

    Makkonen, R.; Asmi, A.; Kerminen, V.-M.; Boy, M.; Arneth, A.; Hari, P.; Kulmala, M.

    2012-02-01

    The number concentration of cloud droplets determines several climatically relevant cloud properties. A major cause for the high uncertainty in the indirect aerosol forcing is the availability of cloud condensation nuclei (CCN), which in turn is highly sensitive to atmospheric new particle formation. Here we present the effect of new particle formation on anthropogenic aerosol forcing in present-day (year 2000) and future (year 2100) conditions. The present-day total aerosol forcing is increased from -1.0 W m-2 to -1.6 W m-2 when nucleation is introduced into the model. Nucleation doubles the change in aerosol forcing between years 2000 and 2100, from +0.6 W m-2 to +1.4 W m-2. Two climate feedbacks are studied, resulting in additional negative forcings of -0.1 W m-2 (+10% DMS emissions in year 2100) and -0.5 W m-2 (+50% BVOC emissions in year 2100). With the total aerosol forcing diminishing in response to air pollution control measures taking effect, warming from increased greenhouse gas concentrations can potentially increase at a very rapid rate.

  18. Controls on Turbulent Mixing in a Strongly Stratified and Sheared Tidal River Plume

    Energy Technology Data Exchange (ETDEWEB)

    Jurisa, Joseph T.; Nash, Jonathan D.; Moum, James N.; Kilcher, Levi F.

    2016-08-01

    Considerable effort has been made to parameterize turbulent kinetic energy (TKE) dissipation rate ..epsilon.. and mixing in buoyant plumes and stratified shear flows. Here, a parameterization based on Kunze et al. is examined, which estimates ..epsilon.. as the amount of energy contained in an unstable shear layer (Ri < Ric) that must be dissipated to increase the Richardson number Ri = N2/S2 to a critical value Ric within a turbulent decay time scale. Observations from the tidal Columbia River plume are used to quantitatively assess the relevant parameters controlling ..epsilon.. over a range of tidal and river discharge forcings. Observed ..epsilon.. is found to be characterized by Kunze et al.'s form within a factor of 2, while exhibiting slightly decreased skill near Ri = Ric. Observed dissipation rates are compared to estimates from a constant interfacial drag formulation that neglects the direct effects of stratification. This is found to be appropriate in energetic regimes when the bulk-averaged Richardson number Rib is less than Ric/4. However, when Rib > Ric/4, the effects of stratification must be included. Similarly, ..epsilon.. scaled by the bulk velocity and density differences over the plume displays a clear dependence on Rib, decreasing as Rib approaches Ric. The Kunze et al. ..epsilon.. parameterization is modified to form an expression for the nondimensional dissipation rate that is solely a function of Rib, displaying good agreement with the observations. It is suggested that this formulation is broadly applicable for unstable to marginally unstable stratified shear flows.

  19. Biological control of Aspergillus flavus growth and subsequent ...

    African Journals Online (AJOL)

    ONOS

    2010-07-05

    Jul 5, 2010 ... 1School of Biological Sciences, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia,. 2Department of Botany, Osmania University, Hyderabad, India. ... the biocontrol agents tested, culture filtrate of Rhodococcus ...

  20. Analysis of water control in an underground mine under strong karst media influence (Vazante mine, Brazil)

    Science.gov (United States)

    Ninanya, Hugo; Guiguer, Nilson; Vargas, Eurípedes A.; Nascimento, Gustavo; Araujo, Edmar; Cazarin, Caroline L.

    2018-05-01

    This work presents analysis of groundwater flow conditions and groundwater control measures for Vazante underground mine located in the state of Minas Gerais, Brazil. According to field observations, groundwater flow processes in this mine are highly influenced by the presence of karst features located in the near-surface terrain next to Santa Catarina River. The karstic features, such as caves, sinkholes, dolines and conduits, have direct contact with the aquifer and tend to increase water flow into the mine. These effects are more acute in areas under the influence of groundwater-level drawdown by pumping. Numerical analyses of this condition were carried out using the computer program FEFLOW. This program represents karstic features as one-dimensional discrete flow conduits inside a three-dimensional finite element structure representing the geologic medium following a combined discrete-continuum approach for representing the karst system. These features create preferential flow paths between the river and mine; their incorporation into the model is able to more realistically represent the hydrogeological environment of the mine surroundings. In order to mitigate the water-inflow problems, impermeabilization of the river through construction of a reinforced concrete channel was incorporated in the developed hydrogeological model. Different scenarios for channelization lengths for the most critical zones along the river were studied. Obtained results were able to compare effectiveness of different river channelization scenarios. It was also possible to determine whether the use of these impermeabilization measures would be able to reduce, in large part, the elevated costs of pumping inside the mine.

  1. WILD PIGS: BIOLOGY, DAMAGE, CONTROL TECHINQUES AND MANAGEMENT

    Energy Technology Data Exchange (ETDEWEB)

    Mayer, John; Brisbin, I. Lehr

    2009-12-31

    about anything; and, they can live just about anywhere. On top of that, wild pigs are both very difficult to control and, with the possible exception of island ecosystems, almost impossible to eradicate (Dickson et al. 2001, Sweeney et al. 2003). The solution to the wild pig problem has not been readily apparent. The ultimate answer as to how to control these animals has not been found to date. In many ways, wild pigs are America's most successful large invasive species. All of which means that wild pigs are a veritable nightmare for land and resource managers trying to keep the numbers of these animals and the damage that they do under control. Since the more that one knows about an invasive species, the easier it is to deal with and hopefully control. For wild pigs then, it is better to 'know thy enemy' than to not, especially if one expects to be able to successfully control them. In an effort to better 'know thy enemy,' a two-day symposium was held in Augusta, Georgia, on April 21-22, 2004. This symposium was organized and sponsored by U.S.D.A. Forest Service-Savannah River (USFS-SR), U. S. Department of Energy-Savannah River Operations Office (DOE-SR), the Westinghouse Savannah River Company (WSRC), the South Carolina Chapter of the Soil & Water Conservation Society, and the Savannah River Ecology Laboratory (SREL). The goal of this symposium was to assemble researchers and land managers to first address various aspects of the biology and damage of wild pigs, and then review the control techniques and management of this invasive species. The result would then be a collected synopsis of what is known about wild pigs in the United States. Although the focus of the symposium was primarily directed toward federal agencies, presenters also included professionals from academic institutions, and private-sector control contractors and land managers. Most of the organizations associated with implementing this symposium were affiliated with the

  2. Ultra-thin and strong formvar-based membranes with controlled porosity for micro- and nano-scale systems

    Science.gov (United States)

    Auchter, Eric; Marquez, Justin; Stevens, Garrison; Silva, Rebecca; Mcculloch, Quinn; Guengerich, Quintessa; Blair, Andrew; Litchfield, Sebastian; Li, Nan; Sheehan, Chris; Chamberlin, Rebecca; Yarbro, Stephen L.; Dervishi, Enkeleda

    2018-05-01

    We present a methodology for developing ultra-thin and strong formvar-based membranes with controlled morphologies. Formvar is a thin hydrophilic and oleophilic polymer inert to most chemicals and resistant to radiation. The formvar-based membranes are viable materials as support structures in micro- and macro-scale systems depending on thinness and porosity control. Tunable sub-micron thick porous membranes with 20%–65% porosity were synthesized by controlling the ratios of formvar, glycerol, and chloroform. This synthesis process does not require complex separation or handling methods and allows for the production of strong, thin, and porous formvar-based membranes. An expansive array of these membrane characterizations including chemical compatibility, mechanical responses, wettability, as well as the mathematical simulations as a function of porosity has been presented. The wide range of chemical compatibility allows for membrane applications in various environments, where other polymers would not be suitable. Our formvar-based membranes were found to have an elastic modulus of 7.8 GPa, a surface free energy of 50 mN m‑1 and an average thickness of 125 nm. Stochastic model simulations indicate that formvar with the porosity of ∼50% is the optimal membrane formulation, allowing the most material transfer across the membrane while also withstanding the highest simulated pressure loadings before tearing. Development of novel, resilient and versatile membranes with controlled porosity offers a wide range of exciting applications in the fields of nanoscience, microfluidics, and MEMS.

  3. The role of ionizing radiation in biological control of agricultural pests

    International Nuclear Information System (INIS)

    Mansour, M.

    2011-01-01

    Although the commercial biological control industry is growing, it still represents only a small portion of the international market of pest control sales (about 3%). This low ratio is due to several factors including high cost of production of biological control agents and technical and regulatory difficulties that complicate the shipping procedures and create trade barriers. This article summarizes the role of ionizing radiation in supporting the use of biological control agents in insect pest control and concentrates on its role in the production, transport, distribution, and release of parasites and predators and the advantages that ionizing radiation can offer, in comparison with traditional techniques. (author)

  4. Precise Control of Molecular Dynamics with a Femtosecond Frequency Comb - A Weak Field Route to Strong Field Coherent Control

    OpenAIRE

    Pe'er, Avi; Shapiro, Evgeny A.; Stowe, Matthew C.; Shapiro, Moshe; Ye, Jun

    2006-01-01

    We present a general and highly efficient scheme for performing narrow-band Raman transitions between molecular vibrational levels using a coherent train of weak pump-dump pairs of shaped ultrashort pulses. The use of weak pulses permits an analytic description within the framework of coherent control in the perturbative regime, while coherent accumulation of many pulse pairs enables near unity transfer efficiency with a high spectral selectivity, thus forming a powerful combination of pump-d...

  5. Radiochemical and biological control of metaiodobenzyl-guanidine (MIBG) labeled with 131I

    International Nuclear Information System (INIS)

    Barboza, M.R.F.F. de; Muramoto, E.; Colturato, M.T.; Silva Valente Goncalves, R. da; Pereira, N.P.S. de; Almeida, M.A.T.M. de; Silva, C.P.G. da.

    1988-07-01

    This study shows the standardization of the radiochemical control of MIBG - 131 I in eletrophoretic system and also the biological control in Wistar rat for a period of time, not longer than 60 minutes after tracer administration. (author) [pt

  6. Biological control of fusarium wilt of tomato by antagonist fungi and ...

    African Journals Online (AJOL)

    Yomi

    2012-01-16

    Jan 16, 2012 ... Key words: Biological control, fusarium wilt, tomato, antagonist fungi, cyanobacteria. INTRODUCTION ... severely affected by wilt disease caused by F. oxysporum f. sp. ..... Changing options for the control of deciduous fruit.

  7. The status of biological control and recommendations for improving uptake for the future

    NARCIS (Netherlands)

    Barratt, B.I.P.; Moran, V.C.; Bigler, F.; Lenteren, van J.C.

    2018-01-01

    Classical and augmentative biological control of insect pests and weeds has enjoyed a long history of successes. However, biocontrol practices have not been as universally accepted or optimally utilised as they could be. An International Organisation for Biological Control (IOBC) initiative brought

  8. 21 CFR 310.4 - Biologics; products subject to license control.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 5 2010-04-01 2010-04-01 false Biologics; products subject to license control... to license control. (a) If a drug has an approved license under section 351 of the Public Health.... (b) To obtain marketing approval for radioactive biological products for human use, as defined in...

  9. Managing conflict over biological control: the case of strawberry guava in Hawaii

    Science.gov (United States)

    Tracy Johnson

    2016-01-01

    Biological control researchers commonly avoid targets with potential for high conflict, but for certain highly damaging invaders with no viable management alternatives, it may be necessary to consider biological control even when it is likely to generate conflict. Discussed here is a case study, strawberry guava (Psidium cattleianum Sabine...

  10. Controlled fabrication of the strong emission YVO4:Eu3+ nanoparticles and nanowires by microwave assisted chemical synthesis

    International Nuclear Information System (INIS)

    Huong, Tran Thu; Vinh, Le Thi; Phuong, Ha Thi; Khuyen, Hoang Thi; Anh, Tran Kim; Tu, Vu Duc; Minh, Le Quoc

    2016-01-01

    In this report, we are presenting the controlled fabrication results of the strong emission YVO 4 : Eu 3+ nanoparticles and nanowires by microwave which is assisted chemical synthesis. The effects of incorporated synthesis conditions such as microwave irradiated powers, pH values and concentration of chemical composition on properties of nanomaterials are also investigated to obtain the controllable size and homogenous morphology. Morphological and optical properties of YVO 4 : Eu 3+ prepared products which have been characterized by X-ray diffraction (XRD), field emission micrcroscopy (FESEM) and photoluminescence spectroscopy. As based from result of synthesized samples, we found that the changing of pH values, microwave irradiated powers and chemical composition rise to change reform the size and shape of materials from nanoparticles (diameter about 20 nm) to wires shape (with about 500÷800 nm length and 10÷20 nm width). The photoluminescence (PL) spectroscopy measurements of YVO 4 : Eu 3+ nanostructure materials under UV excitation showed that: the strong luminescence in red region with narrow lines corresponding to the intra-4f transitions of 5 D 0 – 7 F j (j=1, 2, 3, and 4) of Eu 3+ ions with the highest luminescence intensity of 5 D 0 → 7 F 2 transition. - Highlights: • The strong emission YVO 4 :Eu 3+ nanostructure materials were successfully synthesized by microwave assisted chemical synthesis. • The size, morphology and luminescence of the YVO 4 :Eu 3+ nanostructure materials can be controlled by the solution pH, microwave irradiated powers and chemical composition. • These YVO 4 :Eu 3+ nanostructure materials above can potentially applied in various fields of application, especially in luminescent labeling and visualization in biomedical application.

  11. Biological stability of drinking water : Controlling factors, methods, and challenges

    NARCIS (Netherlands)

    Prest, E.I.E.D.; Hammes, F.; Van Loosdrecht, M.C.M.; Vrouwenvelder, J.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

  12. Application of Confined Blasting in Water-Filled Deep Holes to Control Strong Rock Pressure in Hard Rock Mines

    Directory of Open Access Journals (Sweden)

    Jingxuan Yang

    2017-11-01

    Full Text Available In extra-thick coal seams, mining operations can lead to large-scale disturbances, complex overburden structures, and frequent and strong strata behavior in the stope, which are serious threats to mine safety. This study analyzed the overburden structure and strata behavior and proposed the technique of confined blasting in water-filled deep holes as a measure to prevent strong rock pressure. It found that there are two primary reasons for the high effectiveness of the proposed technique in presplitting hard coal and rock. First, the fracture water enables much more efficient transfer of dynamic load due to its incompressibility. Second, the subsequent expansion of water can further split the rock by compression. A mechanical model was used to reveal how the process of confined blasting in water-filled deep holes presplit roof. Moreover, practical implementation of this technique was found to improve the structure of hard, thick roof and prevent strong rock pressure, demonstrating its effectiveness in roof control.

  13. ALCOHOL CONSUMPTION WITH FAMILY PATTERN RELATED TO STRONG PERSONALITIES: A CASE-CONTROL STUDY IN MARRIED ROMANIAN STUDENTS.

    Science.gov (United States)

    Petrescu, Cristina

    2016-01-01

    In the study conducted the aim was to investigate strong personalities (SP) related to alcohol consumption in married students from Romania. Consisted in 2 samples: a case-sample (23 alcohol consumer students with a family pattern of weekly consumption, 47.8% male and 52.2% female, aged 21-29 years) and a control-sample (42 no-alcohol consumer students without a family pattern of consumption, 26.2% male and 73.8% female, aged 21-29 years), selected from a sample of 176 married students. An observational inquiry (case-control) consisted in applying 2 questionnaires: Health Questionnaire (60 items, 7: Q43-Q49 -alcohol consumption) and Strong Personalities Questionnaire (88 items, alpha-Crohnbach index-0.823). Statistical analysis was performed by the aid of SPSS 20 Program. For alcohol consumer students with weekly pattern of consumption the main reason of alcohol consumption was curiosity (60.9%) and the most frequent consumed alcohol was beer (38.6%, 500-3000 ml/week). Personalities' profiles revealed V-hyperthymic, III-hyperperseverant and X-emotive strong personalities (SP) as being symptomatic (over 50% symptomatic level-SL) for both samples, with a difference (control-case) for X-emotive SP (71.7% students--57.1% students, respectively). I-demonstrative, VII-cyclothymic and IV-unruly SP presented a difference between case (symptomatic: 61.8%; 61.8% and 61.8% students, respectively) and control (symptomatic: 36.8%; 37.5% and 45% students, respectively) samples. A statistically significant difference case-control samples was demonstrated for I-Demonstrative (item S29: chi square chi2 = 10.65; Sig.0.002; gamma correlation gamma=0.73; Sig.0.002) and for X-emotive (item S25: chi2 = 8.76; gamma = -0.66; Sig.0.003) SP. In conclusion, a relation SP-alcohol consumption in married students is suggested.

  14. Biological control of fruit-tree red spider mite

    NARCIS (Netherlands)

    Rabbinge, R.

    1976-01-01

    During the last decade, integrated pest control systems have been developed for several crops. One of the main fields of research in integrated control has been the control of orchard pests. Experience with modified spraying programmes in apple orchards, the increasing resistance of spider

  15. The biological control as a strategy to support nontraditional agricultural exports in Peru: An empirical analysis

    Directory of Open Access Journals (Sweden)

    Franklin Duarte Cueva

    2012-12-01

    Full Text Available The study is oriented to explore the general characteristics of agriculture, the biological control as a pest control mechanism and agro export industry. In this context, we try to promote the use of biological control as a strategy to support nontraditional exports related to products such as asparagus and fresh avocados grown in the La Libertad Department (Peru, through an agronomic and management approach. Biological control is the basis of integrated pest management (IPM and contributes to the conservation of agricultural ecosystems allowing to export companies reduce costs, fulfill international phytosanitary measures and supports the preservation of the environment and health. Thus, the Peruvian agro export companies could build a sustainable competitive advantage and seek a positioning as socially responsible firms. We analyze variables such as crop statistics, comparative costs between biological control and chemical control, main destination markets for asparagus and fresh avocados, international standards, among others.

  16. Habitat affinity of resident natural enemies of the invasive Aphis glycines (Hemiptera: Aphididae), on soybean, with comments on biological control.

    Science.gov (United States)

    Brewer, Michael J; Noma, Takuji

    2010-06-01

    We integrated a natural enemy survey of the broader landscape into a more traditional survey for Aphis glycines Matsumura (Hemiptera: Aphididae), parasitoids and predatory flies on soybean using A. glycines-infested soybean, Glycine max (L.) Merr., placed in cropped and noncropped plant systems to complement visual field observations. Across three sites and 5 yr, 18 parasitoids and predatory flies in total (Hymenoptera: Aphelinidae [two species] and Bracondae [seven species], Diptera: Cecidomyiidae [one species], Syrphidae [seven species], Chamaemyiidae [one species]) were detected, with significant variability in recoveries detected across plant system treatments and strong contrasts in habitat affinity detected among species. Lysiphlebus testaceipes Cresson was the most frequently detected parasitoid, and no differences in abundance were detected in cropped (soybean, wheat [Triticum aestivum L.], corn [Zea mays L.], and alfalfa [Medicago sativa L.]) and noncropped (poplar [Populus euramericana (Dode) Guinier] and early successional vegetation) areas. In contrast, Binodoxys kelloggensis Pike, Starý & Brewer had strong habitat affinity for poplar and early successional vegetation. The low recoveries seasonally and across habitats of Aphelinus asychis Walker, Aphelinus sp., and Aphidius colemoni Viereck make their suitability to A. glycines on soybean highly suspect. The widespread occurrence of many of the flies reflects their broad habitat affinity and host aphid ranges. The consistent low field observations of parasitism and predation suggest that resident parasitoids and predatory flies are unlikely to contribute substantially to A. glycines suppression, at least during the conventional time period early in the pest invasion when classical biological control activities are considered. For selected species that were relatively well represented across plant systems (i.e., L. testaceipes and Aphidoletes aphidimyza Rondani), conservation biological control efforts

  17. Trade-offs in parasitism efficiency and brood size mediate parasitoid coexistence, with implications for biological control of the invasive emerald ash borer

    Science.gov (United States)

    Parasitoids often are selected for use as biological control agents because of their high host specificity, yet such host specificity can result in strong interspecific competition. However, few studies have examined if and how various extrinsic factors (such as parasitism efficiency) influence the ...

  18. Enhancing biological control of basal stem rot disease (Ganoderma boninense) in oil palm plantations.

    Science.gov (United States)

    Susanto, A; Sudharto, P S; Purba, R Y

    2005-01-01

    Basal Stem Rot (BSR) disease caused by Ganoderma boninense is the most destructive disease in oil palm, especially in Indonesia and Malaysia. The available control measures for BSR disease such as cultural practices and mechanical and chemical treatment have not proved satisfactory due to the fact that Ganoderma has various resting stages such as melanised mycelium, basidiospores and pseudosclerotia. Alternative control measures to overcome the Ganoderma problem are focused on the use of biological control agents and planting resistant material. Present studies conducted at Indonesian Oil Palm Research Institute (IOPRI) are focused on enhancing the use of biological control agents for Ganoderma. These activities include screening biological agents from the oil palm rhizosphere in order to evaluate their effectiveness as biological agents in glasshouse and field trials, testing their antagonistic activities in large scale experiments and eradicating potential disease inoculum with biological agents. Several promising biological agents have been isolated, mainly Trichoderma harzianum, T. viride, Gliocladium viride, Pseudomonas fluorescens, and Bacillus sp. A glasshouse and field trial for Ganoderma control indicated that treatment with T. harzianum and G. viride was superior to Bacillus sp. A large scale trial showed that the disease incidence was lower in a field treated with biological agents than in untreated fields. In a short term programme, research activities at IOPRI are currently focusing on selecting fungi that can completely degrade plant material in order to eradicate inoculum. Digging holes around the palm bole and adding empty fruit bunches have been investigated as ways to stimulate biological agents.

  19. Environmental risk assessment for Neodryinus typhlocybae, biological control agent against Metcalfa pruinosa, for Austria

    Directory of Open Access Journals (Sweden)

    Gudrun Strauss

    2013-03-01

    Full Text Available The potential environmental risks of Neodryinus typhlocybae, a parasitic wasp from North America, were evaluated with regard to its safe use as an exotic biocontrol agent for the planthopper Metcalfa pruinosa in Austria. Following an earlier host range study of N. typhlocybae conducted in the laboratory, the present study assessed the potential for establishment and spread as well as negative indirect effects on non-target organisms. The potential release sites in Austria were analysed for matching of the climatic requirements for establishment of N. typhlocybae. The two proposed release locations, Vienna and Graz, have a predominantly similar climate to the parasitoid’s region of origin, though the comparably cooler mean summer temperatures might result in a low emergence rate of the partial second generation. The natural spread potential of N. typhlocybae was reviewed and is considered to be sufficiently good for released individuals to reach nearby sites infested with M. pruinosa. However, a perceptible spreading of N. typhlocybae females only occurs a few years after release and seems to be strongly dependent on the host density. Gelis areator, a hyperparasitoid of N. typhlocybae known to occur in Austria, might have negative effects on the population of the beneficial organism. Advantages and disadvantages of chemical and biological control methods against M. pruinosa were evaluated. It is concluded that N. typhlocybae is very well suited as a biological control agent for M. pruinosa in Austria, as no adverse effects on non-target species are expected but its release offers advantages with regard to sustainable and environmentally friendly pest management.

  20. Complete Host Range Testing on Common Reed with Potential Biological Control Agents and Investigation into Biological Control for Flowering Rush

    Science.gov (United States)

    2016-07-01

    CR-16-5 v Preface This report was prepared by Drs. Patrick Häfliger and Hariet Hinz, Centre for Agriculture and Bioscience International (CABI...through Cornell University, the Washington Department of Agriculture , the Washington Department of Ecology, the Washington Department of Natural...capacity during biological invasion in an aquatic plant Butomus umbellatus (Butomaceae). American Journal of Botany 92:495–502. Dieckmann, L. 1983

  1. Biological Control of Solenopsis Fire Ants by Pseudacteon Parasitoids: Theory and Practice

    Directory of Open Access Journals (Sweden)

    Lloyd W. Morrison

    2012-01-01

    Full Text Available Pseudacteon parasitoids are potential biocontrol agents of invasive Solenopsis fire ants. Pseudacteon species that parasitize the invasive S. invicta Buren and S. richteri Forel have been introduced to, and naturally dispersed across, the southeastern USA, although there is no evidence yet that Solenopsis host ant populations have decreased. The ability of introduced Pseudacteon species to regulate Solenopsis populations will depend upon the relative importance of top-down effects in the recipient communities. In this paper, I examine the characteristics of the Pseudacteon/Solenopsis parasitoid/host system and evaluate the extent to which research findings are consistent with top-down control. Laboratory and field experiments evaluating Solenopsis population regulation have been equivocal, and overall the available evidence provides little support for strong top-down effects in this system. Competitive exclusion may occur among introduced Pseudacteon species, and future efforts at biological control are likely to be more efficacious if they focus on other types of natural enemies.

  2. Anaerobic Digestion. Student Manual. Biological Treatment Process Control.

    Science.gov (United States)

    Carnegie, John W., Ed.

    This student manual contains the textual material for a four-lesson unit on anaerobic digestion control. Areas addressed include: (1) anaerobic sludge digestion (considering the nature of raw sludge, purposes of anaerobic digestion, the results of digestion, types of equipment, and other topics); (2) digester process control (considering feeding…

  3. Obtaining strong ferromagnetism in diluted Gd-doped ZnO thin films through controlled Gd-defect complexes

    KAUST Repository

    Roqan, Iman S.

    2015-02-21

    We demonstrate the fabrication of reproducible long-range ferromagnetism (FM) in highly crystalline GdxZn1-xO thin films by controlling the defects. Films are grown on lattice-matched substrates by pulsed laser deposition at low oxygen pressures (≤25 mTorr) and low Gd concentrations (x ≤ 0.009). These films feature strong FM (10 μB per Gd atom) at room temperature. While films deposited at higher oxygen pressure do not exhibit FM, FM is recovered by post-annealing these films under vacuum. These findings reveal the contribution of oxygen deficiency defects to the long-range FM. We demonstrate the possible FM mechanisms, which are confirmed by density functional theory study, and show that Gd dopants are essential for establishing FM that is induced by intrinsic defects in these films.

  4. Obtaining strong ferromagnetism in diluted Gd-doped ZnO thin films through controlled Gd-defect complexes

    KAUST Repository

    Roqan, Iman S.; Venkatesh, S.; Zhang, Z.; Hussain, S.; Bantounas, Ioannis; Franklin, J. B.; Flemban, Tahani H.; Zou, B.; Lee, J.-S.; Schwingenschlö gl, Udo; Petrov, P. K.; Ryan, M. P.; Alford, N. M.

    2015-01-01

    We demonstrate the fabrication of reproducible long-range ferromagnetism (FM) in highly crystalline GdxZn1-xO thin films by controlling the defects. Films are grown on lattice-matched substrates by pulsed laser deposition at low oxygen pressures (≤25 mTorr) and low Gd concentrations (x ≤ 0.009). These films feature strong FM (10 μB per Gd atom) at room temperature. While films deposited at higher oxygen pressure do not exhibit FM, FM is recovered by post-annealing these films under vacuum. These findings reveal the contribution of oxygen deficiency defects to the long-range FM. We demonstrate the possible FM mechanisms, which are confirmed by density functional theory study, and show that Gd dopants are essential for establishing FM that is induced by intrinsic defects in these films.

  5. First controlled vertical flight of a biologically inspired microrobot

    Energy Technology Data Exchange (ETDEWEB)

    Perez-Arancibia, Nestor O; Ma, Kevin Y; Greenberg, Jack D; Wood, Robert J [School of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138 (United States); Galloway, Kevin C, E-mail: nperez@seas.harvard.edu, E-mail: kevinma@seas.harvard.edu, E-mail: kevin.galloway@wyss.harvard.edu, E-mail: jdgreenb@seas.harvard.edu, E-mail: rjwood@eecs.harvard.edu [Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA 02115 (United States)

    2011-09-15

    In this paper, we present experimental results on altitude control of a flying microrobot. The problem is approached in two stages. In the first stage, system identification of two relevant subsystems composing the microrobot is performed, using a static flapping experimental setup. In the second stage, the information gathered through the static flapping experiments is employed to design the controller used in vertical flight. The design of the proposed controller relies on the idea of treating an exciting signal as a subsystem of the microrobot. The methods and results presented here are a key step toward achieving total autonomy of bio-inspired flying microrobots.

  6. First controlled vertical flight of a biologically inspired microrobot

    International Nuclear Information System (INIS)

    Perez-Arancibia, Nestor O; Ma, Kevin Y; Greenberg, Jack D; Wood, Robert J; Galloway, Kevin C

    2011-01-01

    In this paper, we present experimental results on altitude control of a flying microrobot. The problem is approached in two stages. In the first stage, system identification of two relevant subsystems composing the microrobot is performed, using a static flapping experimental setup. In the second stage, the information gathered through the static flapping experiments is employed to design the controller used in vertical flight. The design of the proposed controller relies on the idea of treating an exciting signal as a subsystem of the microrobot. The methods and results presented here are a key step toward achieving total autonomy of bio-inspired flying microrobots.

  7. Biological control and management of the detoxication wastewater treatment technologies

    Directory of Open Access Journals (Sweden)

    Topalova Yana

    2007-01-01

    Full Text Available Detoxication technologies require the combination of theoretical and practical knowledge of xenobiotic biodegradation, wastewater treatment technologies, and management rules. The purpose of this complicated combination is to propose specialized strategies for detoxication, based on lab- and pilot-scale modeling. These strategies include preliminary created algorithms for preventing the risk of water pollution and sediments. The technologies and algorithms are essentially important outcome, applied in the textile, pharmaceutical, cosmetic, woodtreating, and oiltreating industries. In this paper four rehabilitation technologies for pretreatment of water contaminated by pentachlorophenol (PCP have been developed in the frame of the European and Bulgarian National projects. Emphasize is put on the biological systems and their potential of detoxication management. The light and transmission electron microscopy of the reconstructed activated sludges the microbial, kinetic and enzymological indicators are presented and approved as critical points in the biocontrol.

  8. SOME ASPECTS OF THE BIOLOGY AND CONTROL OF ...

    African Journals Online (AJOL)

    Key Words: Callosobruchus maculatus, developmental period, soya bean, Azadirachta indica, Citrus sinensis. ASPECTS DE LA BIOLOGIE ET DU CONTROLE DU CALLOSOBRUCHUS MACULATUS (F.) SUR LA CONSERVATION DES GRAINES DE SOJA DES VARIETES GLYCINE MAX (L.) MERR NOTE DE SYNTHESE

  9. Biological control of schistosome transmission in flowing water habitats.

    Science.gov (United States)

    Jobin, W R; Laracuente, A

    1979-09-01

    Marisa cornuarietis was evaluated in Puerto Rico for control of schistosome transmission in flowing water. A population of Biomphalaria glabrata and their schistosome infections disappeared after introduction of 20,000 M. cornuarietis to an endemic stream, while in nearby untreated streams the B. glabrata population remained stable and the schistosome prevalence increased. This method cost U.S. $0.10 per capita for over a year of protection, 5%-10% of the cost of chemical control.

  10. Differential physiological responses of dalmatian toadflax, Linaria dalmatica L. Miller, to injury from two insect biological control agents: Implications for decision-making in biological control

    Science.gov (United States)

    Robert K. D. Peterson; Sharlene E. Sing; David K. Weaver

    2005-01-01

    Successful biological control of invasive weeds with specialist herbivorous insects is predicated on the assumption that the injury stresses the weeds sufficiently to cause reductions in individual fitness. Because plant gas exchange directly impacts growth and fitness, characterizing how injury affects these primary processes may provide a key indicator of...

  11. Do biological-based strategies hold promise to biofouling control in MBRs?

    KAUST Repository

    Malaeb, Lilian; Le-Clech, Pierre; Vrouwenvelder, Johannes S.; Ayoub, George M.; Saikaly, Pascal

    2013-01-01

    . The reason for the slow advancement in successful control of biofouling is largely attributed to the complex interactions of involved biological compounds and the lack of representative-for-practice experimental approaches to evaluate potential effective

  12. Holarchical Systems and Emotional Holons : Biologically-Inspired System Designs for Control of Autonomous Aerial Vehicles

    Science.gov (United States)

    Ippolito, Corey; Plice, Laura; Pisanich, Greg

    2003-01-01

    The BEES (Bio-inspired Engineering for Exploration Systems) for Mars project at NASA Ames Research Center has the goal of developing bio-inspired flight control strategies to enable aerial explorers for Mars scientific investigations. This paper presents a summary of our ongoing research into biologically inspired system designs for control of unmanned autonomous aerial vehicle communities for Mars exploration. First, we present cooperative design considerations for robotic explorers based on the holarchical nature of biological systems and communities. Second, an outline of an architecture for cognitive decision making and control of individual robotic explorers is presented, modeled after the emotional nervous system of cognitive biological systems. Keywords: Holarchy, Biologically Inspired, Emotional UAV Flight Control

  13. Biological control of saltcedar (Tamarix spp.) by saltcedar leaf beetles (Diorhabda spp.): effects on small mammals

    Science.gov (United States)

    The spread of introduced saltcedar (Tamarix spp.) throughout many riparian systems across the western United States motivated the introduction of biological control agents that are specific to saltcedar, saltcedar leaf beetles (Diorhabda carinulata, D. elongata; Chrysomelidae). I monitored small mam...

  14. Costs and benefits of biological control of invasive alien plants: case studies from South Africa

    CSIR Research Space (South Africa)

    Van Wilgen, BW

    2004-01-01

    Full Text Available Invasive alien species can have significant negative environmental and economic impacts. Such species are often controlled biologically by means of introducing host-specific insects or pathogens that can reduce the species' invasive potential...

  15. Parasitoids attacking emerald ash borers in western Pennsylvania and their potential use in biological control

    Science.gov (United States)

    J.J. Duan; R.W. Fuester; J. Wildonger; P.B. Taylor; S. Barth; S-E. Spichiger

    2009-01-01

    Current biological control programs against the emerald ash borer (EAB, Agrilus planipennis Fairmaire) have primarily focused on the introduction and releases of exotic parasitoids from China, home of the pest origin....

  16. Biological control of toxic cyanobacteria by mixotrophic predators: an experimental test of intraguild predation theory

    NARCIS (Netherlands)

    Wilken, S.; Verspagen, J.M.H.; Naus-Wiezer, S.M.H.; Van Donk, E.; Huisman, Jef

    2014-01-01

    Intraguild predators both feed on and compete with their intraguild prey. In theory, intraguild predators can therefore be very effective as biological control agents of intraguild prey species, especially in productive environments. We investigated this hypothesis using the mixotrophic chrysophyte

  17. Distinguishing Biologically Controlled Calcareous Biomineralization in Fossil Organisms Using Electron Backscatter Diffraction (EBSD)

    Science.gov (United States)

    Päßler, Jan-Filip; Jarochowska, Emilia; Bestmann, Michel; Munnecke, Axel

    2018-02-01

    Although carbonate-precipitating cyanobacteria are ubiquitous in aquatic ecosystems today, the criteria used to identify them in the geological record are subjective and rarely testable. Differences in the mode of biomineralization between cyanobacteria and eukaryotes, i.e. biologically induced calcification (BIM) vs. biologically controlled calcification (BCM), result in different crystallographic structures which might be used as a criterion to test cyanobacterial affinities. Cyanobacteria are often used as a ‘wastebasket taxon’, to which various microfossils are assigned. The lack of a testable criterion for the identification of cyanobacteria may bias their fossil record severely. We employed electron backscatter diffraction (EBSD) to investigate the structure of calcareous skeletons in two microproblematica widespread in Palaeozoic marine ecosystems: Rothpletzella, hypothesized to be a cyanobacterium, and an incertae sedis microorganism Allonema. We used a calcareous trilobite shell as a BCM reference. The mineralized structure of Allonema has a simple single-layered structure of acicular crystals perpendicular to the surface of the organism. The c-axes of these crystals are parallel to the elongation and thereby normal to the surface of the organism. EBSD pole figures and misorientation axes distribution reveal a fibre texture around the c-axis with a small degree of variation (up to 30°), indicating a highly ordered structure. A comparable pattern was found in the trilobite shell. This structure allows excluding biologically induced mineralization as the mechanism of shell formation in Allonema. In Rothpletzella, the c-axes of the microcrystalline sheath show a broader clustering compared to Allonema, but still reveal crystals tending to be perpendicular to the surface of the organism. The misorientation axes of adjacent crystals show an approximately random distribution. Rothpletzella also shares morphological similarities with extant cyanobacteria. We

  18. 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

  19. The biological basis for the control of prenatal irradiation

    International Nuclear Information System (INIS)

    1988-01-01

    The embryo and fetus have been generally considered to be more sensitive than the adult to the detrimental effects of radiation exposure. In particular, recent re-evaluations of epidemiological data on human population exposed to radiation have suggested that there may be greater sensitivity than heretofore recognized to the induction of mental retardation and reduced intelligence by exposure during gestation. To assist national authorities in evaluating this problem and establishing appropriate protection measures for limiting the dose to the embryo and fetus and, thus, to pregnant or potentially pregnant women, the Nuclear Energy Agency has appointed a Group of Consultants to assemble and evaluate the biological data relevant to the protection of the human conceptus, and to make recommendations for achieving this in the operational practice. The Group has surveyed the human data dealing with the biologcal effects of radiation exposure at low doses, and has supplemented this with information derived from animal studies. The Group has also taken full account of the studies and recommendations issued in this area by other international organizations, primarily the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) and the International Commission on Radiological Protection (ICRP). This report is published under the responsibility of the Secretary General of the OECD, and does not commit Member governments of the Organization

  20. Biology and control of the raspberry crown borer (Lepidoptera: Sesiidae).

    Science.gov (United States)

    McKern, Jacquelyn A; Johnson, Donn T; Lewis, Barbara A

    2007-04-01

    This study explored the biology of raspberry crown borer, Pennisetia marginata (Harris) (Lepidoptera: Sesiidae), in Arkansas and the optimum timing for insecticide and nematode applications. The duration of P. marginata's life cycle was observed to be 1 yr in Arkansas. Insecticide trials revealed that bifenthrin, chlorpyrifos, imidacloprid, metaflumizone, and metofluthrin efficacy were comparable with that of azinphosmethyl, the only labeled insecticide for P. marginata in brambles until 2005. Applications on 23 October 2003 for plots treated with bifenthrin, chlorpyrifos, and azinphosmethyl resulted in >88% reduction in larvae per crown. Applications on 3 November 2004 of metaflumizone, metofluthrin, and bifenthrin resulted in >89% reduction in larvae per crown. Applications on 7 April 2005 for metofluthrin, imidacloprid, bifenthrin, metaflumizone, and benzoylphenyl urea resulted in >64% reduction in the number of larvae per crown. Applications on 6 May 2004 did not reduce larval numbers. The optimum timing for treatments was found to be between October and early April, before the larvae tunneled into the crowns of plants. Applying bifenthrin with as little as 468 liters water/ha (50 gal/acre) was found to be as effective against larvae as higher volumes of spray. Nematode applications were less successful than insecticides. Nematode applications of Steinernemafeltiae, Steinernema carpocapsae, and Heterorhabditis bacteriophora reduced larvae counts per plant by 46, 53, and 33%, respectively.

  1. Control of dynamical self-assembly of strongly Brownian nanoparticles through convective forces induced by ultrafast laser

    Science.gov (United States)

    Ilday, Serim; Akguc, Gursoy B.; Tokel, Onur; Makey, Ghaith; Yavuz, Ozgun; Yavuz, Koray; Pavlov, Ihor; Ilday, F. Omer; Gulseren, Oguz

    We report a new dynamical self-assembly mechanism, where judicious use of convective and strong Brownian forces enables effective patterning of colloidal nanoparticles that are almost two orders of magnitude smaller than the laser beam. Optical trapping or tweezing effects are not involved, but the laser is used to create steep thermal gradients through multi-photon absorption, and thereby guide the colloids through convective forces. Convective forces can be thought as a positive feedback mechanism that helps to form and reinforce pattern, while Brownian motion act as a competing negative feedback mechanism to limit the growth of the pattern, as well as to increase the possibilities of bifurcation into different patterns, analogous to the competition observed in reaction-diffusion systems. By steering stochastic processes through these forces, we are able to gain control over the emergent pattern such as to form-deform-reform of a pattern, to change its shape and transport it spatially within seconds. This enables us to dynamically initiate and control large patterns comprised of hundreds of colloids. Further, by not relying on any specific chemical, optical or magnetic interaction, this new method is, in principle, completely independent of the material type being assembled.

  2. Anaerobic Digestion. Instructor's Guide. Biological Treatment Process Control.

    Science.gov (United States)

    Carnegie, John W., Ed.

    This instructor's guide contains materials needed to teach a four-lesson unit on anaerobic digestion control. These materials include: (1) unit overview; (2) lesson plans; (3) lecture outlines; (4) student worksheets for each lesson (with answers); and (5) two copies of a final quiz (with and without answers). Lesson 1 is a review of the theory of…

  3. Ecological risks of biological control agents: impacts on IPM

    NARCIS (Netherlands)

    Hokkanen, H.M.T.; Lenteren, van J.C.; Menzler-Hokkanen, I.

    2007-01-01

    Since the early days of integrated pest management a sound ecological foundation has been considered essential for the development of effective systems. From time to time, there have been attempts to evaluate the ways in which ecological theory is exploited in pest control, and to review the lessons

  4. Comparison between chemical and biological control of Fusarium ...

    African Journals Online (AJOL)

    ... College of Education, Jeddah, Saudi Arabia. The results revealed that treatment with the fungicide carbomar or T. harzianum as well as with B. subtilis, in presence of F. solani increased the % of healthy seedlings as well as their length , fresh and dry weight than in presence of F. solani alone but still less than the control.

  5. Identifying Ant-Mirid Spatial Interactions to Improve Biological Control in Cacao-Based Agroforestry System.

    Science.gov (United States)

    Bagny Beilhe, Leïla; Piou, Cyril; Tadu, Zéphirin; Babin, Régis

    2018-06-06

    The use of ants for biological control of insect pests was the first reported case of conservation biological control. Direct and indirect community interactions between ants and pests lead to differential spatial pattern. We investigated spatial interactions between mirids, the major cocoa pest in West Africa and numerically dominant ant species, using bivariate point pattern analysis to identify potential biological control agents. We assume that potential biological control agents should display negative spatial interactions with mirids considering their niche overlap. The mirid/ant data were collected in complex cacao-based agroforestry systems sampled in three agroecological areas over a forest-savannah gradient in Cameroon. Three species, Crematogaster striatula Emery (Hymenoptera: Formicidae), Crematogaster clariventris Mayr (Hymenoptera: Formicidae), and Oecophylla longinoda Latreille (Hymenoptera: Formicidae) with high predator and aggressive behaviors were identified as dominant and showed negative spatial relationships with mirids. The weaver ant, O. longinoda was identified as the only potential biological control agent, considering its ubiquity in the plots, the similarity in niche requirements, and the spatial segregation with mirids resulting probably from exclusion mechanisms. Combining bivariate point pattern analysis to good knowledge of insect ecology was an effective method to identify a potentially good biological control agent.

  6. A biologically inspired neural network controller for ballistic arm movements

    Directory of Open Access Journals (Sweden)

    Schmid Maurizio

    2007-09-01

    Full Text Available Abstract Background In humans, the implementation of multijoint tasks of the arm implies a highly complex integration of sensory information, sensorimotor transformations and motor planning. Computational models can be profitably used to better understand the mechanisms sub-serving motor control, thus providing useful perspectives and investigating different control hypotheses. To this purpose, the use of Artificial Neural Networks has been proposed to represent and interpret the movement of upper limb. In this paper, a neural network approach to the modelling of the motor control of a human arm during planar ballistic movements is presented. Methods The developed system is composed of three main computational blocks: 1 a parallel distributed learning scheme that aims at simulating the internal inverse model in the trajectory formation process; 2 a pulse generator, which is responsible for the creation of muscular synergies; and 3 a limb model based on two joints (two degrees of freedom and six muscle-like actuators, that can accommodate for the biomechanical parameters of the arm. The learning paradigm of the neural controller is based on a pure exploration of the working space with no feedback signal. Kinematics provided by the system have been compared with those obtained in literature from experimental data of humans. Results The model reproduces kinematics of arm movements, with bell-shaped wrist velocity profiles and approximately straight trajectories, and gives rise to the generation of synergies for the execution of movements. The model allows achieving amplitude and direction errors of respectively 0.52 cm and 0.2 radians. Curvature values are similar to those encountered in experimental measures with humans. The neural controller also manages environmental modifications such as the insertion of different force fields acting on the end-effector. Conclusion The proposed system has been shown to properly simulate the development of

  7. Mechanization and Control Concepts for Biologically Inspired Micro Aerial Vehicles

    Science.gov (United States)

    Raney, David L.; Slominski, Eric C.

    2003-01-01

    It is possible that MAV designs of the future will exploit flapping flight in order to perform missions that require extreme agility, such as rapid flight beneath a forest canopy or within the confines of a building. Many of nature's most agile flyers generate flapping motions through resonant excitation of an aeroelastically tailored structure: muscle tissue is used to excite a vibratory mode of their flexible wing structure that creates propulsion and lift. A number of MAV concepts have been proposed that would operate in a similar fashion. This paper describes an ongoing research activity in which mechanization and control concepts with application to resonant flapping MAVs are being explored. Structural approaches, mechanical design, sensing and wingbeat control concepts inspired by hummingbirds, bats and insects are examined. Experimental results from a testbed capable of generating vibratory wingbeat patterns that approximately match those exhibited by hummingbirds in hover, cruise, and reverse flight are presented.

  8. Biological Control of Mosquito Vectors: Past, Present, and Future

    Directory of Open Access Journals (Sweden)

    Giovanni Benelli

    2016-10-01

    Full Text Available Mosquitoes represent the major arthropod vectors of human disease worldwide transmitting malaria, lymphatic filariasis, and arboviruses such as dengue virus and Zika virus. Unfortunately, no treatment (in the form of vaccines or drugs is available for most of these diseases andvectorcontrolisstillthemainformofprevention. Thelimitationsoftraditionalinsecticide-based strategies, particularly the development of insecticide resistance, have resulted in significant efforts to develop alternative eco-friendly methods. Biocontrol strategies aim to be sustainable and target a range of different mosquito species to reduce the current reliance on insecticide-based mosquito control. In thisreview, weoutline non-insecticide basedstrategiesthat havebeenimplemented orare currently being tested. We also highlight the use of mosquito behavioural knowledge that can be exploited for control strategies.

  9. Computational Biomathematics: Toward Optimal Control of Complex Biological Systems

    Science.gov (United States)

    2016-09-26

    SECURITY CLASSIFICATION OF: 1. REPORT DATE (DD-MM-YYYY) 4. TITLE AND SUBTITLE 13. SUPPLEMENTARY NOTES 12. DISTRIBUTION AVAILIBILITY STATEMENT 6. AUTHORS...neighbor or bi-linear interpolation). The following paper is in preparation: Scaling methods and heuristic algorithms for agent-based models. Matt...The actual method of control used is in the form of heuristic algorithms. In general, these algorithms search through a virtually infinite set of

  10. Biological control of banana black Sigatoka disease with Trichoderma

    OpenAIRE

    Poholl Adan Sagratzki Cavero; Rogério Eiji Hanada; Luadir Gasparotto; Rosalee Albuquerque Coelho Neto; Jorge Teodoro de Souza

    2015-01-01

    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 f...

  11. Biological control of Egyptian broomrape (Orobanche aegyptiaca using Fusarium spp.

    Directory of Open Access Journals (Sweden)

    I. Ghannam

    2007-08-01

    Full Text Available The broomrape (Orobanche spp. is an obligate holoparasitic weed that causes severe damage to many important vegetable crops. Many broomrape control strategies have been tested over the years. In this investigation, 125 Fusarium spp. isolates were recovered from diseased broomrape spikes collected from fields in agricultural areas near Hebron. The pathogenicity of isolates on broomrape was evaluated using an inoculum suspension containing mycelia and conidia. The most effective Fusarium isolates significantly increased the dead spikes of broomrape by 33.6–72.7% compared to the control; there was no obvious pathogenic effect on the tomato plants. Fusarium spp. isolates Fu 20, 25 and 119 were identified as F. solani, while Fu 30, 52, 59, 87 and 12-04 were F. oxysporum. In addition, the two previously known Fusarium strains, F. oxysporum strain EId (CNCM-I-1622 (Foxy and F. arthrosporioides strain E4a (CNCM-I-1621 (Farth were equally effective in controlling broomrape parasitizing tomato plants grown in pots, where the dead spikes of broomrape increased by 50.0 and 51.6%, respectively.

  12. 75 FR 28233 - Availability of an Environmental Assessment for a Biological Control Agent for Asian Citrus Psyllid

    Science.gov (United States)

    2010-05-20

    ...] Availability of an Environmental Assessment for a Biological Control Agent for Asian Citrus Psyllid AGENCY... radiata, into the continental United States for use as a biological control agent to reduce the severity... of an alternative biological control agent, an encyrtid wasp, (Diaphorencyrtus aligarhensis). However...

  13. 77 FR 46373 - Field Release of Aphelinus glycinis for the Biological Control of the Soybean Aphid in the...

    Science.gov (United States)

    2012-08-03

    ... Inspection Service [Docket No APHIS-2012-0061] Field Release of Aphelinus glycinis for the Biological Control... for the biological control of the soybean aphid, Aphis glycines, in the continental United States. We... glycinis for the Biological Control of the Soybean Aphid in the Continental United States'' (March 2012...

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

    Science.gov (United States)

    Rahman, M. M.; Ali, M. E.; Khan, A. A.; Akanda, A. M.; Uddin, Md. Kamal; Hashim, U.; Abd Hamid, S. B.

    2012-01-01

    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. PMID:22645446

  15. Straight lines of neutron scattering in biology: a review of basic controls in SANS and EINS.

    Science.gov (United States)

    Zaccai, Giuseppe

    2012-10-01

    Neutron and X-ray beams in scattering experiments have similar wavelengths and explore the same length scale (~1 Å or 0.1 nm). Data collection and analysis are also broadly similar for both radiation types. There are fundamental differences, however, between the interaction of X-rays and neutrons with matter, which makes them strongly complementary for structural studies in biology. The property of neutrons to distinguish natural abundance hydrogen from its deuterium isotope and the dispersion relation that leads to the energy of ~1 Å neutrons being of the order of thermal energy are well known. They form the basis, respectively, of contrast variation on the one hand and energy-resolved scattering experiments to study macromolecular dynamics-neutron-specific scattering methods on the other. Interestingly, analysis procedures for the structural and dynamics experiments display common aspects that can be expressed as straight-line relationships. These not only act as controls of good sample preparation, but also yield model-free parameters on an absolute scale that provide fundamental information on the structure and dynamics of the system under study.

  16. 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.

  17. New experimental approaches to the biology of flight control systems.

    Science.gov (United States)

    Taylor, Graham K; Bacic, Marko; Bomphrey, Richard J; Carruthers, Anna C; Gillies, James; Walker, Simon M; Thomas, Adrian L R

    2008-01-01

    Here we consider how new experimental approaches in biomechanics can be used to attain a systems-level understanding of the dynamics of animal flight control. Our aim in this paper is not to provide detailed results and analysis, but rather to tackle several conceptual and methodological issues that have stood in the way of experimentalists in achieving this goal, and to offer tools for overcoming these. We begin by discussing the interplay between analytical and empirical methods, emphasizing that the structure of the models we use to analyse flight control dictates the empirical measurements we must make in order to parameterize them. We then provide a conceptual overview of tethered-flight paradigms, comparing classical ;open-loop' and ;closed-loop' setups, and describe a flight simulator that we have recently developed for making flight dynamics measurements on tethered insects. Next, we provide a conceptual overview of free-flight paradigms, focusing on the need to use system identification techniques in order to analyse the data they provide, and describe two new techniques that we have developed for making flight dynamics measurements on freely flying birds. First, we describe a technique for obtaining inertial measurements of the orientation, angular velocity and acceleration of a steppe eagle Aquila nipalensis in wide-ranging free flight, together with synchronized measurements of wing and tail kinematics using onboard instrumentation and video cameras. Second, we describe a photogrammetric method to measure the 3D wing kinematics of the eagle during take-off and landing. In each case, we provide demonstration data to illustrate the kinds of information available from each method. We conclude by discussing the prospects for systems-level analyses of flight control using these techniques and others like them.

  18. Control of biological hazards in cold smoked salmon production

    DEFF Research Database (Denmark)

    Huss, Hans Henrik; Embarek, Peter Karim Ben; Jeppesen, V.F.

    1995-01-01

    An outline of the common processing technology for cold smoked salmon in Denmark is presented. The safety hazards related to pathogenic bacteria, parasites and biogenic amines are discussed with special emphasis on hazards related to Clostridium botulinum and Listeria monocytogenes. Critical...... control points are identified for all hazards except growth of L. monocytogenes. For this reason a limitation of shelf life to three weeks at +5 degrees C far cold smoked vacuum-packed salmon having greater than or equal to 3% water phase salt is recommended...

  19. Control of BTEX migration using a biologically enhanced permeable barrier

    International Nuclear Information System (INIS)

    Borden, R.C.; Goin, R.T.; Kao, C.M.

    1997-01-01

    A permeable barrier system, consisting of a line of closely spaced wells, was installed perpendicular to ground water flow to control the migration of a dissolved hydrocarbon plume. The wells were charged with concrete briquets that release oxygen and nitrate at a controlled rate, enhancing aerobic biodegradation in the downgradient aquifer. Laboratory batch reactor experiments were conducted to identify concrete mixtures that slowly released oxygen over an extended time period. A full-scale permeable barrier system using ORC was constructed at a gasoline-spill site. During the first 242 days of operation, total BTEX decreased from 17 to 3.4 mg/L and dissolved oxygen increased from 0.4 to 1.8 mg/L during transport through the barrier. Over time, BTEX treatment efficiencies declined, indicating the barrier system had become less effective in releasing oxygen and nutrients to the highly contaminated portion of the aquifer. Point dilution tests and sediment analyses performed at the conclusion of the project indicated that the aquifer in the vicinity of the remediation wells had been clogged by precipitation with iron minerals

  20. The role and control of sludge age in biological nutrient removal activated sludge systems.

    Science.gov (United States)

    Ekama, G A

    2010-01-01

    The sludge age is the most fundamental and important parameter in the design, operation and control of biological nutrient removal (BNR) activated sludge (AS) systems. Generally, the better the effluent and waste sludge quality required from the system, the longer the sludge age, the larger the biological reactor and the more wastewater characteristics need to be known. Controlling the reactor concentration does not control sludge age, only the mass of sludge in the system. When nitrification is a requirement, sludge age control becomes a requirement and the secondary settling tanks can no longer serve the dual purpose of clarifier and waste activated sludge thickeners. The easiest and most practical way to control sludge age is with hydraulic control by wasting a defined proportion of the reactor volume daily. In AS plants with reactor concentration control, nitrification fails first. With hydraulic control of sludge age, nitrification will not fail, rather the plant fails by shedding solids over the secondary settling tank effluent weirs.

  1. Systematics and biology of Cotesia typhae sp. n. (Hymenoptera, Braconidae, Microgastrinae, a potential biological control agent against the noctuid Mediterranean corn borer, Sesamia nonagrioides

    Directory of Open Access Journals (Sweden)

    Laure Kaiser

    2017-07-01

    Full Text Available Many parasitoid species are subjected to strong selective pressures from their host, and their adaptive response may result in the formation of genetically differentiated populations, called host races. When environmental factors and reproduction traits prevent gene flow, host races become distinct species. Such a process has recently been documented within the Cotesia flavipes species complex, all of which are larval parasitoids of moth species whose larvae are stem borers of Poales. A previous study on the African species C. sesamiae, incorporating molecular, ecological and biological data on various samples, showed that a particular population could be considered as a distinct species, because it was specialized at both host (Sesamia nonagrioides and plant (Typha domingensis levels, and reproductively isolated from other C. sesamiae. Due to its potential for the biological control of S. nonagrioides, a serious corn pest in Mediterranean countries and even in Iran, we describe here Cotesia typhae Fernandez-Triana sp. n. The new species is characterized on the basis of morphological, molecular, ecological and geographical data, which proved to be useful for future collection and rapid identification of the species within the species complex. Fecundity traits and parasitism success on African and European S. nonagrioides populations, estimated by laboratory studies, are also included.

  2. Convergent mechanism of roadway driven along with strong roof of special thick stratum and its controlled measures

    Energy Technology Data Exchange (ETDEWEB)

    Zhai, X.; Qian, M.; Jing, G.; Li, Y. [China University of Mining and Technology, Beijing (China). College of Resource and Safety Engineering

    2004-06-01

    The trapezoidal cross-section roadway, driven along with its medium and fine grain sandstone roof in special thick stratum, was situated in shale strata of the Wu{sub 2} coal seam of the Shihhotze Perno-carboniferous group. Rock-lining wall was employed in roadway, which its roof is in the free situation. Under the action of virgin stress, the surrounding rock of roadway was stable. While under the action of fixed abutment pressure arisen from protection pillar of roadway, which if two sides seams were extracted the free strong roof of roadway was stable. But its two sides rock-lining walls was fractured, partially broken into pieces, and its floor heave was obvious. The velocity of floor heave is 0.4 - 0.8 mm/d. The size of the broken zone of surrounding rock of roadway doubled. An effective load coefficient of surrounding rock was quoted to illustrate these phenomena. The main reasons of roadway convergence are that rock property of surrounding rock is inferior, protection pillars affects its stability, and the supporting pattern employed is improper. Effective measures to control roadway convergence should be bolting and grouting lining, which mainly consolidate surrounding rock of roadway. 4 refs., 1 fig.

  3. Fault diagnosis for the heat exchanger of the aircraft environmental control system based on the strong tracking filter.

    Science.gov (United States)

    Ma, Jian; Lu, Chen; Liu, Hongmei

    2015-01-01

    The aircraft environmental control system (ECS) is a critical aircraft system, which provides the appropriate environmental conditions to ensure the safe transport of air passengers and equipment. The functionality and reliability of ECS have received increasing attention in recent years. The heat exchanger is a particularly significant component of the ECS, because its failure decreases the system's efficiency, which can lead to catastrophic consequences. Fault diagnosis of the heat exchanger is necessary to prevent risks. However, two problems hinder the implementation of the heat exchanger fault diagnosis in practice. First, the actual measured parameter of the heat exchanger cannot effectively reflect the fault occurrence, whereas the heat exchanger faults are usually depicted by utilizing the corresponding fault-related state parameters that cannot be measured directly. Second, both the traditional Extended Kalman Filter (EKF) and the EKF-based Double Model Filter have certain disadvantages, such as sensitivity to modeling errors and difficulties in selection of initialization values. To solve the aforementioned problems, this paper presents a fault-related parameter adaptive estimation method based on strong tracking filter (STF) and Modified Bayes classification algorithm for fault detection and failure mode classification of the heat exchanger, respectively. Heat exchanger fault simulation is conducted to generate fault data, through which the proposed methods are validated. The results demonstrate that the proposed methods are capable of providing accurate, stable, and rapid fault diagnosis of the heat exchanger.

  4. Fault diagnosis for the heat exchanger of the aircraft environmental control system based on the strong tracking filter.

    Directory of Open Access Journals (Sweden)

    Jian Ma

    Full Text Available The aircraft environmental control system (ECS is a critical aircraft system, which provides the appropriate environmental conditions to ensure the safe transport of air passengers and equipment. The functionality and reliability of ECS have received increasing attention in recent years. The heat exchanger is a particularly significant component of the ECS, because its failure decreases the system's efficiency, which can lead to catastrophic consequences. Fault diagnosis of the heat exchanger is necessary to prevent risks. However, two problems hinder the implementation of the heat exchanger fault diagnosis in practice. First, the actual measured parameter of the heat exchanger cannot effectively reflect the fault occurrence, whereas the heat exchanger faults are usually depicted by utilizing the corresponding fault-related state parameters that cannot be measured directly. Second, both the traditional Extended Kalman Filter (EKF and the EKF-based Double Model Filter have certain disadvantages, such as sensitivity to modeling errors and difficulties in selection of initialization values. To solve the aforementioned problems, this paper presents a fault-related parameter adaptive estimation method based on strong tracking filter (STF and Modified Bayes classification algorithm for fault detection and failure mode classification of the heat exchanger, respectively. Heat exchanger fault simulation is conducted to generate fault data, through which the proposed methods are validated. The results demonstrate that the proposed methods are capable of providing accurate, stable, and rapid fault diagnosis of the heat exchanger.

  5. 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.

  6. <strong>Relative Biological Effect of Antiprotonsstrong>> strong>

    DEFF Research Database (Denmark)

    Bassler, Niels; Holzscheiter, Michael

    nuclear research facility CERN. A beam of 126 MeV antiprotons, corresponding to about 12 cm range in water, was spread out to a SOBP with a width of 1 cm. Dosimetry experiments were carried out with ionization chambers, alanine pellets and radiochromic film, and the results were used for benchmarking...

  7. Zika virus: History, emergence, biology, and prospects for control.

    Science.gov (United States)

    Weaver, Scott C; Costa, Federico; Garcia-Blanco, Mariano A; Ko, Albert I; Ribeiro, Guilherme S; Saade, George; Shi, Pei-Yong; Vasilakis, Nikos

    2016-06-01

    Zika virus (ZIKV), a previously obscure flavivirus closely related to dengue, West Nile, Japanese encephalitis and yellow fever viruses, has emerged explosively since 2007 to cause a series of epidemics in Micronesia, the South Pacific, and most recently the Americas. After its putative evolution in sub-Saharan Africa, ZIKV spread in the distant past to Asia and has probably emerged on multiple occasions into urban transmission cycles involving Aedes (Stegomyia) spp. mosquitoes and human amplification hosts, accompanied by a relatively mild dengue-like illness. The unprecedented numbers of people infected during recent outbreaks in the South Pacific and the Americas may have resulted in enough ZIKV infections to notice relatively rare congenital microcephaly and Guillain-Barré syndromes. Another hypothesis is that phenotypic changes in Asian lineage ZIKV strains led to these disease outcomes. Here, we review potential strategies to control the ongoing outbreak through vector-centric approaches as well as the prospects for the development of vaccines and therapeutics. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. Biological control of dodder (Cuscuta campestris L. by fungi pathogens

    Directory of Open Access Journals (Sweden)

    F. Fallahpour

    2016-04-01

    Full Text Available Parasite weeds are the most important yield reducing factors, and among them dodder (Cuscuta campestris L. is an obligate parasite of many plant families. In order to find a suitable biocontrol agent for dodder a study was conducted based on a randomized complete design with four replications at research greenhouse of Faculty of Agriculture, Ferdowsi University of Mashhad, Iran during 2007-2009. Diseased dodders sampled from sugarbeet farms of Chenaran, Iran. After culturing and isolating exiting fungi from infected tissues of dodder, Fusarium sp., Alternaria sp. and Colletotrichum sp. were recognized. Inoculation of isolates was carried out with concenteration of 1×108 spores per ml sterile water at different growth stages of dodder in labratoary and greenhouse. Among different fungi, isolate of 323 of F. oxysporum showed an effective control on germination of dodder seeds and the highest level of plant pathogencity was before the contact of dodder with host and infection in older plants decreased. Infection of this isolate with crops such as sugarbeet (Beta vulgaris L., alfalfa (Medigago sativa L., basil (Ocimum basilicum L., wheat (Triticum aestivum L. and barley (Hordeum vulgare L. showed no symptoms.

  9. Biology and control of swamp dodder (Cuscuta gronovii)

    International Nuclear Information System (INIS)

    Bewick, T.A.

    1987-01-01

    A simple model predicting swamp dodder (Cuscuta gronovii Willd.) emergence was developed. The model states that 0.1% of the cranberry seedlings will emerge after 150 to 170 GDD have accumulated after the winter ice has melted on the cranberry beds, using 0 C as the low temperature threshold. Experiments in cranberry showed that pronamide [3,5-dichloro-(N-1,1-dimethyl-2-propynyl)benzamide] was effective in controlling swamp dodder when applied preemergence. Rates below 2.4 kg ai/ha appeared to be safe for cranberry plants and fruit. Experiments with 14 C glyphosate showed that the herbicide moved out of carrot leaves to the physiological sinks in the plant. In carrots parasitized by swamp dodder the dodder acted as one of the strongest sinks for photosynthates from the host. In cranberry glyphosate moved out of the leaves, but most remained in the stem to which the treated leaves were attached. The only physiological sinks that accumulated significant amounts of label were the stem apices. The concentration of the herbicide in this sink decreased with time. Swamp dodder stems were able to absorb glyphosate directly from solution

  10. Assessing the status of biological control as a management tool for suppression of invasive alien plants in South Africa

    OpenAIRE

    Zachariades, Costas; Paterson, Iain D.; Strathie, Lorraine W.; Hill, Martin P.; van Wilgen, Brian W.

    2017-01-01

    Background: Biological control of invasive alien plants (IAPs) using introduced natural enemies contributes significantly to sustained, cost-effective management of natural resources in South Africa. The status of, and prospects for, biological control is therefore integral to National Status Reports (NSRs) on Biological Invasions, the first of which is due in 2017. Objectives: Our aim was to evaluate the status of, and prospects for, biological control of IAPs in South Africa. We discuss...

  11. Biologically inspired control of humanoid robot arms robust and adaptive approaches

    CERN Document Server

    Spiers, Adam; Herrmann, Guido

    2016-01-01

    This book investigates a biologically inspired method of robot arm control, developed with the objective of synthesising human-like motion dynamically, using nonlinear, robust and adaptive control techniques in practical robot systems. The control method caters to a rising interest in humanoid robots and the need for appropriate control schemes to match these systems. Unlike the classic kinematic schemes used in industrial manipulators, the dynamic approaches proposed here promote human-like motion with better exploitation of the robot’s physical structure. This also benefits human-robot interaction. The control schemes proposed in this book are inspired by a wealth of human-motion literature that indicates the drivers of motion to be dynamic, model-based and optimal. Such considerations lend themselves nicely to achievement via nonlinear control techniques without the necessity for extensive and complex biological models. The operational-space method of robot control forms the basis of many of the techniqu...

  12. Quantifying conservation biological control for management of Bemisia tabaci (Hemiptera: Aleyrodidae) in cotton

    Science.gov (United States)

    Conservation biological control can be an effective tactic for minimizing insect-induced damage to agricultural production. The most effective manner of applying CBC is through an Integrated Pest Management (IPM) strategy, combining many tactics including cultural controls, pest sampling, the use of...

  13. Hybridization between a native and introduced predator of Adelgidae: An unintended result of classical biological control

    Science.gov (United States)

    N.P. Havill; Gina Davis; David Mausel; Joanne Klein; Richard McDonald; Cera Jones; Melissa Fischer; Scott Salom; Adelgisa. Caccone

    2012-01-01

    Hybridization between introduced biological control agents and native species has the potential to impact native biodiversity and pest control efforts. This study reports progress towards predicting the outcome of hybridization between two beetle species, the introduced Laricobius nigrinus Fender and the native L. rubidus LeConte...

  14. 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,

  15. Candidate predators for biological control of the poultry red mite Dermanyssus gallinae

    NARCIS (Netherlands)

    Lesna, I.; Wolfs, P.; Faraji, F.; Roy, L.; Komdeur, J.; Sabelis, M.W.

    2009-01-01

    The poultry red mite, Dermanyssus gallinae, is currently a significant pest in the poultry industry in Europe. Biological control by the introduction of predatory mites is one of the various options for controlling poultry red mites. Here, we present the first results of an attempt to identify

  16. Candidate predators for biological control of the poultry red mite Dermanyssus gallinae

    NARCIS (Netherlands)

    Lesna, Izabela; Wolfs, Peter; Faraji, Farid; Roy, Lise; Komdeur, Jan; Sabelis, Maurice W.

    The poultry red mite, Dermanyssus gallinae, is currently a significant pest in the poultry industry in Europe. Biological control by the introduction of predatory mites is one of the various options for controlling poultry red mites. Here, we present the first results of an attempt to identify

  17. Control biológico del entrenamiento de resistencia. Biological control of endurance training.

    Directory of Open Access Journals (Sweden)

    González Gross, Marcela

    2006-01-01

    Full Text Available ResumenLa alta exigencia en los deportistas de elite hace cada vez más necesario controlar el proceso de adaptación al entrenamiento. El objetivo de esta revisión es analizar la información biológica de un análisis de sangre, al objeto de obtener información de la carga de entrenamiento en atletas de resistencia. La mayor parte de los parámetros sanguíneos han sido empleados, más que para determinar el proceso del entrenamiento, precisamente, para lo opuesto: el sobreentrenamiento. La concentración en plasma de sustratos metabólicos (glucosa y ácidos grasos no son parámetros que pueda utilizarse para controlar el entrenamiento, debido a las bajas especificidad y sensibilidad. No obstante, la concentración de determinados enzimas que intervienen en la utilización de los sustratos puede ser importante. Valores de creatín kinasa superiores a 200 U/l en una persona sana sugiere claramente que la carga de entrenamiento total de una determinada sesión ha sido elevada. La concentración en plasma de algún producto de degradación del catabolismo también puede señalar la adaptación del organismo al entrenamiento. La concentración de ácido láctico en plasma es la herramienta más común en la valoración de la carga de entrenamiento. La concentración de urea es un buen marcador biológico de la carga de entrenamiento. Valores superiores a 8 mmol/l en varones y de 6,5 mmol/l en mujeres, indican que el entrenamiento ha sido muy intenso. La determinación de otros productos (amonio o sustratos (glutamina se han utilizado para detectar el sobreentrenamiento.AbstractThe high exigency in the elite sportsmen does more necessary to control the process of training adaptation. The purpose of this review is to analyze the biological information of a blood analysis to obtain data of load training in endurance athletes. Most blood parameters has been used to evaluate the overtraining state instead of determining the training process. The

  18. The Main Biological Hazards in Animal Biosafety Level 2 Facilities and Strategies for Control.

    Science.gov (United States)

    Li, Xiao Yan; Xue, Kang Ning; Jiang, Jin Sheng; Lu, Xuan Cheng

    2016-04-01

    Concern about the biological hazards involved in microbiological research, especially research involving laboratory animals, has increased in recent years. Working in an animal biosafety level 2 facility (ABSL-2), commonly used for research on infectious diseases, poses various biological hazards. Here, the regulations and standards related to laboratory biosafety in China are introduced, the potential biological hazards present in ABSL-2 facilities are analyzed, and a series of strategies to control the hazards are presented. Copyright © 2016 The Editorial Board of Biomedical and Environmental Sciences. Published by China CDC. All rights reserved.

  19. labelling and quality control of some 99m Tc-radiopharmaceuticals of expected biological activity

    International Nuclear Information System (INIS)

    Abdallah, A.B.I.

    2009-01-01

    this thesis addresses the labelling and quality control of some 99m Tc-radiopharmaceuticals which could be used for infection imaging. this study focuses on the labelling of sarafloxation, gatifloxation and cefepine with technetium-99m and biological evaluation of these labeled complexes and biodistribution in both normal and inflamed mice. the thesis is organized into two chapters: chapter I :labelling of some antibiotics chapter II :biological evaluation.

  20. Biologically Inspired Modular Neural Control for a Leg-Wheel Hybrid Robot

    DEFF Research Database (Denmark)

    Manoonpong, Poramate; Wörgötter, Florentin; Laksanacharoen, Pudit

    2014-01-01

    In this article we present modular neural control for a leg-wheel hybrid robot consisting of three legs with omnidirectional wheels. This neural control has four main modules having their functional origin in biological neural systems. A minimal recurrent control (MRC) module is for sensory signal...... processing and state memorization. Its outputs drive two front wheels while the rear wheel is controlled through a velocity regulating network (VRN) module. In parallel, a neural oscillator network module serves as a central pattern generator (CPG) controls leg movements for sidestepping. Stepping directions...... or they can serve as useful modules for other module-based neural control applications....

  1. Modelling approach for biological control of insect pest by releasing infected pest

    International Nuclear Information System (INIS)

    Tan Yuanshun; Chen Lansun

    2009-01-01

    Models of biological control have a long history of theoretical development that have focused on the interactions between a predator and a prey. Here we have extended the classical epidemic model to include a continuous and impulsive pest control strategies by releasing the infected pests bred in laboratory. For the continuous model, the results imply that the susceptible pest goes to extinct if the threshold condition R 0 0 > 1, the positive equilibrium of continuous model is globally asymptotically stable. Similarly, the threshold condition which guarantees the global stability of the susceptible pest-eradication periodic solution is obtained for the model with impulsive control strategy. Consequently, based on the results obtained in this paper, the control strategies which maintain the pests below an acceptably low level are discussed by controlling the release rate and impulsive period. Finally, the biological implications of the results and the efficiency of two control strategies are also discussed

  2. <strong>Mini-project>

    DEFF Research Database (Denmark)

    Katajainen, Jyrki

    2008-01-01

    In this project the goal is to develop the safe * family of containers for the CPH STL. The containers to be developed should be safer and more reliable than any of the existing implementations. A special focus should be put on strong exception safety since none of the existing prototypes available...

  3. Hybridization of an invasive shrub affects tolerance and resistance to defoliation by a biological control agent

    OpenAIRE

    Williams, Wyatt I; Friedman, Jonathan M; Gaskin, John F; Norton, Andrew P

    2014-01-01

    Evolution has contributed to the successful invasion of exotic plant species in their introduced ranges, but how evolution affects particular control strategies is still under evaluation. For instance, classical biological control, a common strategy involving the utilization of highly specific natural enemies to control exotic pests, may be negatively affected by host hybridization because of shifts in plant traits, such as root allocation or chemical constituents. We investigated introgressi...

  4. Natural biological control of pest mites in Brazilian sun coffee agroecosystems.

    Science.gov (United States)

    Teodoro, Adenir V; Sarmento, Renato A; Rêgo, Adriano S; da Graça S Maciel, Anilde

    2010-06-01

    Coffee is one of the leading commodities in tropical America. Although plantations are usually established under a canopy of trees in most producing countries in the region, Brazilian coffee is mostly produced under full sun conditions. Such simple, single-crop agroecosystems with intensive agrochemical inputs often suffer with pests like mites. Predatory mites of the family Phytoseiidae are the main natural enemies associated with pest mites in the field. However, these beneficial arthropods struggle to survive in intensive agroecosystems such as coffee monocultures due to unfavorable microclimatic conditions, widespread pesticide use, and lack of alternative food (pollen, nectar). Conservation biological control uses a range of management strategies to sustain and enhance populations of indigenous natural enemies such as predatory mites. We discuss here conservation biological control as a strategy to improve biological control of pest mites by native predatory mites in Brazilian coffee monocultures as well as some related patents.

  5. Using consumption rate to assess potential predators for biological control of white perch

    Directory of Open Access Journals (Sweden)

    Gosch N.J.C.

    2011-08-01

    Full Text Available Control of undesirable fishes is important in aquatic systems, and using predation as a tool for biological control is an attractive option to fishery biologists. However, determining the appropriate predators for biological control is critical for success. The objective of this study was to evaluate the utility of consumption rate as an index to determine the most effective predators for biological control of an invasive fish. Consumption rate values were calculated for nine potential predators that prey on white perch Morone americana in Branched Oak and Pawnee reservoirs, Nebraska. The consumption rate index provided a unique and insightful means of determining the potential effectiveness of each predator species in controlling white perch. Cumulative frequency distributions facilitated interpretation by providing a graphical presentation of consumption rates by all individuals within each predator species. Largemouth bass Micropterus salmoides, walleye Sander vitreus and sauger S. canadensis were the most efficient white perch predators in both reservoirs; however, previous attempts to increase biomass of these predators have failed suggesting that successful biological control is unlikely using existing predator species in these Nebraska reservoirs.

  6. Effect of biological activated carbon pre-treatment to control organic fouling in the microfiltration of biologically treated secondary effluent.

    Science.gov (United States)

    Pramanik, Biplob Kumar; Roddick, Felicity A; Fan, Linhua

    2014-10-15

    Biological activated carbon (BAC) filtration was investigated as a pre-treatment for reducing the organic fouling of a microfiltration membrane (0.1 μm polyvinylidene fluoride) in the treatment of a biologically treated secondary effluent (BTSE) from a municipal wastewater treatment plant. BAC treatment of the BTSE resulted in a marked improvement in permeate flux, which was attributed to the effective removal of organic foulants and particulates. Although the BAC removed significantly less dissolved organic carbon than the granular activated carbon (GAC) treatment which was used as a control for comparison, it led to a markedly greater flux. This was attributed to the effective removal of the very high molecular weight substances such as biopolymers by the BAC through biodegradation and adsorption of those molecules on the biofilm. Size exclusion chromatography showed the BAC treatment led to approximately 30% reduction in these substances, whereas the GAC did not greatly remove these molecules. The BAC treatment led to a greater reduction of loosely-attached and firmly-attached membrane surface foulant, and this was confirmed by attenuated total reflection-fourier transform infrared spectroscopy analysis. This study demonstrated the potential of BAC pre-treatment for reducing organic fouling and thus improving flux for the microfiltration of BTSE. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. Strong interactions

    International Nuclear Information System (INIS)

    Froissart, Marcel

    1976-01-01

    Strong interactions are introduced by their more obvious aspect: nuclear forces. In hadron family, the nucleon octet, OMEGA - decuplet, and quark triply are successively considered. Pion wave having been put at the origin of nuclear forces, low energy phenomena are described, the force being explained as an exchange of structure corresponding to a Regge trajectory in a variable rotating state instead of the exchange of a well defined particle. At high energies the concepts of pomeron, parton and stratons are introduced, pionization and fragmentation are briefly differentiated [fr

  8. Evaluation of impedance on biological Tissues using automatic control measurement system

    Energy Technology Data Exchange (ETDEWEB)

    Kil, Sang Hyeong; Shin, Dong Hoon; Lee, Seong Mo [Pusan National University, Yangsan (Korea, Republic of); Lee, Moo Seok; Kim, Sang Sik [Pusan National University, Busan (Korea, Republic of); Kim, Gun FDo; Lee, Jong Kyu [Pukyung National University, Busan (Korea, Republic of)

    2015-08-15

    Each biological tissue has endemic electrical characteristics owing to various differences such as those in cellular arrangement or organization form. The endemic electrical characteristics change when any biological change occurs. This work is a preliminary study surveying the changes in the electrical characteristics of biological tissue caused by radiation exposure. For protection against radiation hazards, therefore the electrical characteristics of living tissue were evaluated after development of the automatic control measurement system using LabVIEW. No alteration of biological tissues was observed before and after measurement of the electrical characteristics, and the biological tissues exhibited similar patterns. Through repeated measurements using the impedance/gain-phase analyzer, the coefficient of variation was determined as within 10%. The reproducibility impedance phase difference in electrical characteristics of the biological tissue did not change, and the tissue had resistance. The absolute value of impedance decreased constantly in proportion to the frequency. It has become possible to understand the electrical characteristics of biological tissues through the measurements made possible by the use of the developed.

  9. Evaluation of impedance on biological Tissues using automatic control measurement system

    International Nuclear Information System (INIS)

    Kil, Sang Hyeong; Shin, Dong Hoon; Lee, Seong Mo; Lee, Moo Seok; Kim, Sang Sik; Kim, Gun FDo; Lee, Jong Kyu

    2015-01-01

    Each biological tissue has endemic electrical characteristics owing to various differences such as those in cellular arrangement or organization form. The endemic electrical characteristics change when any biological change occurs. This work is a preliminary study surveying the changes in the electrical characteristics of biological tissue caused by radiation exposure. For protection against radiation hazards, therefore the electrical characteristics of living tissue were evaluated after development of the automatic control measurement system using LabVIEW. No alteration of biological tissues was observed before and after measurement of the electrical characteristics, and the biological tissues exhibited similar patterns. Through repeated measurements using the impedance/gain-phase analyzer, the coefficient of variation was determined as within 10%. The reproducibility impedance phase difference in electrical characteristics of the biological tissue did not change, and the tissue had resistance. The absolute value of impedance decreased constantly in proportion to the frequency. It has become possible to understand the electrical characteristics of biological tissues through the measurements made possible by the use of the developed.

  10. Biological Control of the Invasive Dryocosmus kuriphilus (Hymenoptera: Cynipidae - an Overview and the First Trials in Croatia

    Directory of Open Access Journals (Sweden)

    Dinka Matošević

    2014-06-01

    Full Text Available Background and Purpose: Dryocosmus kuriphilus is a globally invasive insect pest, spreading very quickly in new habitats and making serious damage to sweet chestnut forests in Croatia and in several other European countries. Indigenous parasitoid species trophically associated with oak gallwasps have adapted to this new host but cannot effectively regulate its population density. Classical biological control using parasitoid Torymus sinensis has been proven to be the only effective method of controlling the populations of D. kuriphilus and has been successfully applied in Japan, South Korea, the USA and Italy. The aim of this review paper is to provide overview and up-to date knowledge about biological control of D. kurphilus and to describe first steps of introduction of T. sinensis to sweet chestnut forests in Croatia. Conclusions and Future Prospects: Results presented in this paper show adapted biology and behavioural traits of T. sinensis to its host D. kuriphilus. The history and results of introductions of T. sinensis to Japan, the USA, Italy, France and Hungary are shown. The first report of release of T. sinensis to sweet chestnut forests in Croatia is given with discussion on native parasitoids attacking D. kuriphilus. Possible negative effects of T. sinensis on native parasitoid fauna and risks that could influence the successful establishment of T. sinensis in Croatia are discussed. Previous experiences have shown that T. sinensis can successfully control the population density of D. kuriphilus, slowing down the spread and mitigating negative impact of this invasive chestnut pest and keeping the damage of D. kuriphilus at acceptable level. High specificity of T. sinensis suggests that it has limited potential of exploiting native hosts but further detailed monitoring of native parasitoid and possible interactions with introduced T. sinensis is strongly suggested.

  11. 25 years and still going strong: 2'-O-(pyren-1-yl)methylribonucleotides - versatile building blocks for applications in molecular biology, diagnostics and materials science.

    Science.gov (United States)

    Hrdlicka, Patrick J; Karmakar, Saswata

    2017-11-29

    Oligonucleotides (ONs) modified with 2'-O-(pyren-1-yl)methylribonucleotides have been explored for a range of applications in molecular biology, nucleic acid diagnostics, and materials science for more than 25 years. The first part of this review provides an overview of synthetic strategies toward 2'-O-(pyren-1-yl)methylribonucleotides and is followed by a summary of biophysical properties of nucleic acid duplexes modified with these building blocks. Insights from structural studies are then presented to rationalize the reported properties. In the second part, applications of ONs modified with 2'-O-(pyren-1-yl)methyl-RNA monomers are reviewed, which include detection of RNA targets, discrimination of single nucleotide polymorphisms, formation of self-assembled pyrene arrays on nucleic acid scaffolds, the study of charge transfer phenomena in nucleic acid duplexes, and sequence-unrestricted recognition of double-stranded DNA. The predictable binding mode of the pyrene moiety, coupled with the microenvironment-dependent properties and synthetic feasibility, render 2'-O-(pyren-1-yl)methyl-RNA monomers as a promising class of pyrene-functionalized nucleotide building blocks for new applications in molecular biology, nucleic acid diagnostics, and materials science.

  12. Biologically inspired control and modeling of (biorobotic systems and some applications of fractional calculus in mechanics

    Directory of Open Access Journals (Sweden)

    Lazarević Mihailo P.

    2013-01-01

    Full Text Available In this paper, the applications of biologically inspired modeling and control of (biomechanical (nonredundant mechanisms are presented, as well as newly obtained results of author in mechanics which are based on using fractional calculus. First, it is proposed to use biological analog-synergy due to existence of invariant features in the execution of functional motion. Second, the model of (biomechanical system may be obtained using another biological concept called distributed positioning (DP, which is based on the inertial properties and actuation of joints of considered mechanical system. In addition, it is proposed to use other biological principles such as: principle of minimum interaction, which takes a main role in hierarchical structure of control and self-adjusting principle (introduce local positive/negative feedback on control with great amplifying, which allows efficiently realization of control based on iterative natural learning. Also, new, recently obtained results of the author in the fields of stability, electroviscoelasticity, and control theory are presented which are based on using fractional calculus (FC. [Projekat Ministarstva nauke Republike Srbije, br. 35006

  13. The role of evolutionary biology in research and control of liver flukes in Southeast Asia.

    Science.gov (United States)

    Echaubard, Pierre; Sripa, Banchob; Mallory, Frank F; Wilcox, Bruce A

    2016-09-01

    Stimulated largely by the availability of new technology, biomedical research at the molecular-level and chemical-based control approaches arguably dominate the field of infectious diseases. Along with this, the proximate view of disease etiology predominates to the exclusion of the ultimate, evolutionary biology-based, causation perspective. Yet, historically and up to today, research in evolutionary biology has provided much of the foundation for understanding the mechanisms underlying disease transmission dynamics, virulence, and the design of effective integrated control strategies. Here we review the state of knowledge regarding the biology of Asian liver Fluke-host relationship, parasitology, phylodynamics, drug-based interventions and liver Fluke-related cancer etiology from an evolutionary biology perspective. We consider how evolutionary principles, mechanisms and research methods could help refine our understanding of clinical disease associated with infection by Liver Flukes as well as their transmission dynamics. We identify a series of questions for an evolutionary biology research agenda for the liver Fluke that should contribute to an increased understanding of liver Fluke-associated diseases. Finally, we describe an integrative evolutionary medicine approach to liver Fluke prevention and control highlighting the need to better contextualize interventions within a broader human health and sustainable development framework. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. The inception and evolution of a unique masters program in cancer biology, prevention and control.

    Science.gov (United States)

    Cousin, Carolyn; Blancato, Jan

    2010-09-01

    The University of the District of Columbia (UDC) and the Lombardi Comprehensive Cancer Center (LCCC), Georgetown University Medical Center established a Masters Degree Program in Cancer Biology, Prevention and Control at UDC that is jointly administered and taught by UDC and LCCC faculty. The goal of the Masters Degree Program is to educate students as master-level cancer professionals capable of conducting research and service in cancer biology, prevention, and control or to further advance the education of students to pursue doctoral studies. The Program's unique nature is reflected in its philosophy "the best cancer prevention and control researchers are those with a sound understanding of cancer biology". This program is a full-time, 2-year, 36-credit degree in which students take half of their coursework at UDC and half of their coursework at LCCC. During the second year, students are required to conduct research either at LCCC or UDC. Unlike most cancer biology programs, this unique Program emphasizes both cancer biology and cancer outreach training.

  15. Potential for widespread application of biological control of stored-product pests

    DEFF Research Database (Denmark)

    Hansen, Lise Stengaard

    2007-01-01

    Biological control of stored product pests has substantial potential in Europe". This is essentially the conclusion of the activities of a European working group funded by the COST system, an intergovernmental networking system. Working group 4 of COST action 842 (2000-2005) focussed on biologica...... for these situations will contribute to ensuring that stored food products are protected from insect and mite pests using techniques that are safe for consumers, workers and the environment.......Biological control of stored product pests has substantial potential in Europe". This is essentially the conclusion of the activities of a European working group funded by the COST system, an intergovernmental networking system. Working group 4 of COST action 842 (2000-2005) focussed on biological...

  16. Biological Control of Diseases of Vegetables Grown Hydroponically in Thailand: Challenge and Opportunity.

    Science.gov (United States)

    Kanjanamaneesathian, Mana

    2015-01-01

    In Thailand, yield loss due to plant diseases in vegetables grown hydroponically is very high as a result of the growers` lack of knowledge for controlling diseases and their un- willingness to invest in setting-up the proper hydroponic system from the beginning. Severe root rot disease caused by Pythium spp. is frequent and can be anticipated in the hot climate in Thailand. This review focuses on the diseases in temperate lettuces which have been produced hydroponically and have been attacked by plant pathogens, particularly Pythium spp. Biological control of vegetable diseases grown hydroponically has been investigated in Thailand. Research is being carried out to identify effective strains of the antagonists, formulating the applicable products and delivering them appropriately to control the disease. Products of Bacillus subtilis, Chaetomium globosom and Trichoderma harzianum have been recommended for use to control diseases in vegetables grown hydroponically. Control efficacy of these products is varied as the biological products have been used by the growers in the paradigm of using chemical fungicide for disease control in hydroponic production system, overlooking the intrinsic characteristics of the biological control products. The recent patent, which minimizes the effects of sunlight and heat on the nutrient solution without the use of an external energy for cooling the nutrient, should be applied in producing hydroponic vegetables to mitigate poor plant growth and root rot disease outbreak in Thailand.

  17. Fundamental host range of Leptoypha hospita (Hemiptera: Tingidae), a potential biological control agent of Chinese privet

    Science.gov (United States)

    Yanzhuo Zhang; James L. Hanula; Scott Horn; Cera Jones; S. Kristine Braman; Jianghua Sun

    2016-01-01

    Chinese privet, Ligustrum sinense Lour., is an invasive shrub within riparian areas of the southeastern United States. Biological control is considered the most suitable management option for Chinese privet. The potential host range of the lace bug, Leptoypha hospita Drake et...

  18. Biological control in agro-systems by means of the handling of entomophagous insects

    International Nuclear Information System (INIS)

    Nicholls, Clara Ines; Altieri, Miguel A

    1998-01-01

    From several decades ago the importance of natural enemies of the noxious organisms has been recognized. Unfortunately the introduction of the biological control has not had the desired dimension. The indiscriminate use of biocides products has altered the biodiversity of the agro-ecosystem. The parasitoids and predators have suffered the noxious effects of the plaguicides. These natural enemies of the plagues play a momentous paper in the regulation of noxious insects population. The predators of the insecta class register in diverse orders and the abundance of species is impressive. But the knowledge of their importance is only partial. In many countries the kindness of these organisms has not been specified and does not protect them. In the case of parasitoids something similar occurs. It is say that their biotic diversity is incalculable but very few species are exploited. In these two groups rest the classic biological control projects. The successes in projects of biological control are recognized and they are enlarging in several countries but more impulse is required. Due to demands of a sustainable agricultural production it should support the biological control of plagues. In this document general looks on the topic are expounded

  19. Leveraging culture collections for the discovery and development of microbial biological control agents

    Science.gov (United States)

    The incorporation of living microbial biological control agents into integrated pest management programs is highly desirable because it reduces the use of chemical insecticides harmful to livestock, humans and the environment. In addition, it provides an alternative means to combat resistance to che...

  20. The potential use of lures for thrips biological control in greenhouses: practice and theory

    NARCIS (Netherlands)

    Teulon, D.A.J.; Davidson, M.M.; Nielsen, M.C.; Perry, N.B.; Tol, van R.W.H.M.; Kogel, de W.J.

    2008-01-01

    Exploiting the response of thrips pest species to odours has long been a goal for improving thrips pest management including biological control. Applications of attractants could include improved monitoring, push-pull (in conjunction with a repellent odour), lure and kill, and lure and infect

  1. Conservation Biological Control of Pests in the Molecular Era: New Opportunities to Address Old Constraints

    Science.gov (United States)

    Gurr, Geoff M.; You, Minsheng

    2016-01-01

    Biological 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 plant defense 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. PMID:26793225

  2. Low doses of ionizing radiation: Biological effects and regulatory control. Contributed papers

    International Nuclear Information System (INIS)

    1997-11-01

    The International Atomic Energy Agency and the World Health Organization, in cooperation with the United Nations Scientific Committee on the Effects of Atomic Radiation, organized an international conference on Low Doses of Ionizing Radiation: Biological Effects and Regulatory Control, held in seville, Spain, from 17 to 21 November 1997. This technical document contains concise papers submitted to the conference

  3. Low doses of ionizing radiation: Biological effects and regulatory control. Contributed papers

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-11-01

    The International Atomic Energy Agency and the World Health Organization, in cooperation with the United Nations Scientific Committee on the Effects of Atomic Radiation, organized an international conference on Low Doses of Ionizing Radiation: Biological Effects and Regulatory Control, held in seville, Spain, from 17 to 21 November 1997. This technical document contains concise papers submitted to the conference. Refs, figs, tabs.

  4. Economic evaluation of the successful biological control of Azolla filiculoides in South Africa

    CSIR Research Space (South Africa)

    McConnachie, AJ

    2003-09-01

    Full Text Available that it was no longer considered a problem in South Africa. The results reflect the dynamics of biological control on site-specific survey information, and place higher benefit–cost ratios achieved in other national level studies in a better context. It also raises...

  5. The effect of initial density and parasitoid intergenerational survival rate on classical biological control

    International Nuclear Information System (INIS)

    Xiao Yanni; Tang Sanyi

    2008-01-01

    Models of biological control have a long history of theoretical development that have focused on the interaction of a parasitoid and its host. The host-parasitoid systems have identified several important and general factors affecting the long-term dynamics of interacting populations. However, much less is known about how the initial densities of host-parasitoid populations affect the biological control as well as the stability of host-parasitoid systems. To do this, the classical Nicholson-Bailey model with host self-regulation and parasitoid intergenerational survival rate is used to uncover the effect of initial densities on the successful biological control. The results indicate that the simplest Nicholson-Bailey model has various coexistence with a wide range of parameters, including boundary attractors where the parasitoid population is absent and interior attractors where host-parasitoid coexists. The final stable states of host-parasitoid populations depend on their initial densities as well as their ratios, and those results are confirmed by basins of attraction of initial densities. The results also indicate that the parasitoid intergenerational survival rate increases the stability of the host-parasitoid systems. Therefore, the present research can help us to further understand the dynamical behavior of host-parasitoid interactions, to improve the classical biological control and to make management decisions

  6. The Erythraeoidea (Trombidiformes: Prostigmata) as Biological Control Agents, with Special Reference to the Genus Balaustium

    NARCIS (Netherlands)

    Muñoz-Cárdenas, K.; Fuentes-Quintero, L.S.; Rueda-Ramirez, D.; Rodríguez, C.D.; Cantor, R.F.; Carrillo, D.; de Moraes, G.J.; Peña, J.E.

    2015-01-01

    Erythraeoidea is a widely distributed group with great potential for practical use in biological control programs, but whose study has been limited due to the complex life cycle that often includes alteration in feeding behaviour and habitat. Several associations of these mites to different species

  7. Potentials of biological control of plant diseases in the tropics | Ofor ...

    African Journals Online (AJOL)

    This paper highlights the various categories of biological control, which are employed in an Integrated Disease Management (IDM) scheme. These include conservation, classical biocontrol and augmentation. Also, the various types of biocontrol agents/agencies which are currently in use in various parts of the world like, ...

  8. Use of pupal parasitoids as biological control agents of filth flies on equine facilities

    Science.gov (United States)

    House flies, Musca domestica L., and stable flies, Stomoxys calcitrans (L.), (Diptera: Muscidae), are common pests on horse farms. The use of pupal parasitoids as biological control agents for filth flies is becoming more popular on equine facilities; however, there is a lack of information on the e...

  9. Prospects for biological soil-borne disease control: application of indigenous versus synthetic microbiomes

    Science.gov (United States)

    Biological disease control of soil-borne plant diseases has traditionally employed the biopesticide approach whereby single strains or strain mixtures are introduced into production systems through inundative/inoculative release. The approach has significant barriers that have long been recognized,...

  10. Nuclear polyhedrosis virus as a biological control agent for Malacosoma americanum (Lepidoptera: Lasiocampidae)

    Science.gov (United States)

    R.A. Progar; M.J. Rinella; D. Fekedulegn; L. Butler

    2010-01-01

    In addition to damaging trees, the eastern tent caterpillar is implicated in early fetal loss and late-term abortion in horses. In a field study, we evaluated the potential biological control of the caterpillar using eastern tent caterpillar nuclear polyhedrosis virus (ETNPV), a naturally occurring virus that is nearly species-specific. Egg masses were hatched and...

  11. Assessing risks and benefits of floral supplements in conservation biological control

    NARCIS (Netherlands)

    Winkler, K.; Wackers, F.L.; Termorshuizen, A.J.; Lenteren, van J.C.

    2010-01-01

    The use of flowering field margins is often proposed as a method to support biological control in agro-ecosystems. In addition to beneficial insects, many herbivores depend on floral food as well. The indiscriminate use of flowering species in field margins can therefore lead to higher pest numbers.

  12. Host range of Secusio extensa (Lepidoptera: Arctiidae), and potential for biological control of Senecio madagascariensis (Asteraceae)

    Science.gov (United States)

    M. M. Ramadan; K. T. Murai; T. Johnson

    2010-01-01

    Secusio extensa (Lepidoptera: Arctiidae) was evaluated as a potential biological control agent for Madagascar fireweed, Senecio madagascariensis (Asteraceae), which has invaded over 400 000 acres of rangeland in the Hawaiian Islands and is toxic to cattle and horses. The moth was introduced from southeastern Madagascar...

  13. 41 CFR 101-42.1102-5 - Drugs, biologicals, and reagents other than controlled substances.

    Science.gov (United States)

    2010-07-01

    ... 41 Public Contracts and Property Management 2 2010-07-01 2010-07-01 true Drugs, biologicals, and reagents other than controlled substances. 101-42.1102-5 Section 101-42.1102-5 Public Contracts and Property Management Federal Property Management Regulations System FEDERAL PROPERTY MANAGEMENT REGULATIONS...

  14. Using matrix population models to inform biological control management of the wheat stem sawfly, Cephus cinctus

    Science.gov (United States)

    Demographic models are a powerful means of identifying vulnerable life stages of pest species and assessing the potential effectiveness of various management approaches in reducing pest population growth and spread. In a biological control context, such models can be used to focus foreign explorati...

  15. Biological control of Alternaria radicina in seed production of carrots with Ulocladium atrum

    NARCIS (Netherlands)

    Köhl, J.; Langerak, C.J.; Meekes, E.T.M.; Molhoek, W.M.L.

    2004-01-01

    Black rot of carrots is caused by seed-borne Alternaria radicina. Biological control of seed infestation by treatments applied to plants in flower during seed production with the fungal antagonist Ulocladium atrum was investigated in laboratory and field experiments resulting in a reduction of seed

  16. External rostral characters for differentiation of sexes in the biological control agent Mecinus janthinus (Coleoptera: Curculionidae)

    Science.gov (United States)

    Marjolein Schat; Sharlene E. Sing; Robert K. D. Peterson

    2007-01-01

    The stem-boring weevil, Mecinus janthinus (Germar), is a promising, well established classical biological control agent for the exotic invasive weed Dalmatian toadflax (Linaria dalmatica (L.) Mill.) (Scrophulariaceae). In this paper we present readily apparent rostral characters that can be used for sex differentiation of live stem-boring weevils at low magnification....

  17. 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...

  18. Effects of biological control agents and exotic plant invasion on deer mouse populations

    Science.gov (United States)

    Yvette K. Ortega; Dean E. Pearson; Kevin S. McKelvey

    2004-01-01

    Exotic insects are commonly introduced as biological control agents to reduce densities of invasive exotic plants. Although current biocontrol programs for weeds take precautions to minimize ecological risks, little attention is paid to the potential nontarget effects of introduced food subsidies on native consumers. Previous research demonstrated that two gall flies (...

  19. Releases of natural enemies in Hawaii since 1980 for classical biological control of weeds

    Science.gov (United States)

    P. Conant; J. N. Garcia; M. T. Johnson; W. T. Nagamine; C. K. Hirayama; G. P. Markin; R. L. Hill

    2013-01-01

    A comprehensive review of biological control of weeds in Hawaii was last published in 1992, covering 74 natural enemy species released from 1902 through 1980. The present review summarizes releases of 21 natural enemies targeting seven invasive weeds from 1981 to 2010. These projects were carried out by Hawaii Department of Agriculture (HDOA), USDA Forest Service (USFS...

  20. Potential biological control agents for management of cogongrass (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...

  1. Ex-ante analysis of economic returns from biological control of coconut mite in Tanzania

    NARCIS (Netherlands)

    Oleke, J.M.; Manyong, V.; Mignouna, D.; Isinika, A.; Mutabazi, K.; Hanna, R.; Sabelis, M.

    2013-01-01

    The coconut mite, Aceria guerreronis Keifer, has been identified as one of the pests that pose a threat to the coconut industry in Benin. The study presents the simulation results of the economic benefits of the biological control of coconut mites in Benin using a standard economic surplus model. In

  2. Biological control of fusarium wilt of tomato by antagonist fungi and ...

    African Journals Online (AJOL)

    Biological control of Fusarium oxysporum f. sp. lycopersici (FOL) causing wilt disease of tomato was studied in vitro as well as under pot conditions. Dual culture technique showed that Aspergillus niger, Penicillium citrinum, Penicillium sp. and Trichoderma harzianum inhibited the radial colony growth of the test pathogen.

  3. Genome sequences of three strains of Aspergillus flavus for the biological control of Aflatoxin

    Science.gov (United States)

    The genomes of three strains of Aspergillus flavus with demonstrated utility for the biological control of aflatoxin were sequenced. These sequences were assembled with MIRA and annotated with Augustus using A. flavus strain 3357 (NCBI EQ963472) as a reference. Each strain had a genome of 36.3 to ...

  4. Effective landscape scale management of Cirsium arvense (Canada thistle) utilizing biological control

    Science.gov (United States)

    G. P. Markin; D. Larson

    2013-01-01

    The stem mining weevil, Ceutorhynchus litura Fabricius, the gall forming fly, Urophora cardui L., and the seedhead weevil, Larinus planus Fabricius, were established as biological control agents on an 1800 hectare multiple-habitat wildlife refuge in northwestern Oregon in the mid-1990s. At the time, Canada thistle was the most wide spread, aggressive, and difficult...

  5. Status of biological control of the shrub gorse (Ulex europaeus) on the Island of Hawaii

    Science.gov (United States)

    G. P. Markin; P. Conant

    2013-01-01

    On the island of Hawaii, gorse (Ulex europaeus L.) is limited to an isolated core infestation of approximately 2000 hectares with scattered plants and small patches in the surrounding 10,000 hectares. Between 1985 and 2000, seven biological control agents were introduced, five of which successfully established. By 2000, their combined impact had reduced the yearly...

  6. Integration of biological control and transgenic insect protection for mitigation of mycotoxins in corn

    Science.gov (United States)

    Biological control is known to be effective in reducing aflatoxin contamination of corn and some transgenic corn hybrids incur greatly reduced damage from corn earworm (Helicoverpa zea). We conducted seven field trials over two years to test the hypothesis that transgenic insect protection and biol...

  7. Evaluation of biological control of fusarium wilt in gerbera with Trichoderma asperellum

    OpenAIRE

    Daiani Brandler; Luan Junior Divensi; Rodrigo José Tonin; Thalita Pedrozo Pilla; Ines Rezendes; Paola Mendes Milanesi

    2017-01-01

    The increase in flower cultivation in recent years has been reflecting the higher incidence of soil pathogens that can cause serious problems. This study aimed to evaluate the biological control of Fusarium wilt in gerbera with Trichoderma asperellum. The evaluated treatments were: T1) Control, only sterile substrate; T2) Substrate + Fusarium oxysporum; T3) Substrate + Fusarium oxysporum + Trichoderma asperellum; and T4) Substrate + Trichoderma asperellum. For this, the pathogen was isolated ...

  8. Improving the cost-effectiveness, trade and safety of biological control for agricultural insect pests using nuclear techniques

    Science.gov (United States)

    If appropriately applied, biological control offers one of the most promising, environmentally sound, and sustainable control tactics for arthropod pests and weeds for application as part of an integrated pest management (IPM) approach. Public support for biological control as one of the preferred m...

  9. Do biological-based strategies hold promise to biofouling control in MBRs?

    KAUST Repository

    Malaeb, Lilian

    2013-10-01

    Biofouling in membrane bioreactors (MBRs) remains a primary challenge for their wider application, despite the growing acceptance of MBRs worldwide. Research studies on membrane fouling are extensive in the literature, with more than 200 publications on MBR fouling in the last 3 years; yet, improvements in practice on biofouling control and management have been remarkably slow. Commonly applied cleaning methods are only partially effective and membrane replacement often becomes frequent. The reason for the slow advancement in successful control of biofouling is largely attributed to the complex interactions of involved biological compounds and the lack of representative-for-practice experimental approaches to evaluate potential effective control strategies. Biofouling is driven by microorganisms and their associated extra-cellular polymeric substances (EPS) and microbial products. Microorganisms and their products convene together to form matrices that are commonly treated as a black box in conventional control approaches. Biological-based antifouling strategies seem to be a promising constituent of an effective integrated control approach since they target the essence of biofouling problems. However, biological-based strategies are in their developmental phase and several questions should be addressed to set a roadmap for translating existing and new information into sustainable and effective control techniques. This paper investigates membrane biofouling in MBRs from the microbiological perspective to evaluate the potential of biological-based strategies in offering viable control alternatives. Limitations of available control methods highlight the importance of an integrated anti-fouling approach including biological strategies. Successful development of these strategies requires detailed characterization of microorganisms and EPS through the proper selection of analytical tools and assembly of results. Existing microbiological/EPS studies reveal a number of

  10. 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.

  11. Strengthening cancer biology research, prevention, and control while reducing cancer disparities: student perceptions of a collaborative master's degree program in cancer biology, preventions, and control.

    Science.gov (United States)

    Jillson, I A; Cousin, C E; Blancato, J K

    2013-09-01

    This article provides the findings of a survey of previous and current students in the UDC/GU-LCCC master's degree program. This master's degree program, Cancer Biology, Prevention, and Control is administered and taught jointly by faculty of a Minority Serving Institution, the University of the District of Columbia, and the Lombardi Comprehensive Cancer Center to incorporate the strengths of a community-based school with a research intensive medical center. The program was initiated in 2008 through agreements with both University administrations and funding from the National Cancer Institute. The master's degree program is 36 credits with a focus on coursework in biostatistics, epidemiology, tumor biology, cancer prevention, medical ethics, and cancer outreach program design. For two semesters during the second year, students work full-time with a faculty person on a laboratory or outreach project that is a requirement for graduation. Students are supported and encouraged to transition to a doctoral degree after they obtain the master's and many of them are currently in doctorate programs. Since the inception of the program, 45 students have initiated the course of study, 28 have completed the program, and 13 are currently enrolled in the program. The survey was designed to track the students in their current activities, as well as determine which courses, program enhancements, and research experiences were the least and most useful, and to discern students' perceptions of knowledge acquired on various aspects of Cancer Biology Prevention, and Control Master's Program. Thirty of the 35 individuals to whom email requests were sent responded to the survey, for a response rate of 85.7%. The results of this study will inform the strengthening of the Cancer Biology program by the Education Advisory Committee. They can also be used in the development of comparable collaborative master's degree programs designed to address the significant disparities in prevalence of

  12. Studies on the use ofEchinostoma revolutum larvae as an agent for biological control of Fasciola gigantica

    Directory of Open Access Journals (Sweden)

    Sarwitri Endah Estuningsih

    1998-06-01

    Full Text Available The use of Echinostoma revolutum larvae as an agent for biological control of Fasciola gigantica has been studied in the laboratory of Parasitology, Balitvet. Infection of Lymnaea rubiginosa with Echinostoma revolutum increased the growth and mortality rates of the snails and completely suppressed their egg production . These effects were attributed to a destruction of gonads and other organs of the snails by echinostome rediae, production of which commenced during the second week after the infection. From laboratory studies with L. rubiginosa, there was an evidence of strong antagonism between larvae of E. revolutum and larvae of F. gigantica. Concurrent infection of L. rubiginosa with miracidia of F. gigantica and E. Revolutum resulted in that all snails were infected with E. revolutum only, when they were dissected 30 days later. In contrast, 94% of the snails which were exposed to miracidia of F. gigantica only, were infected with larvae of this species after 30 days . When L. rubiginosa were infected with F. gigantica 20 days previously were exposed to infection with E. revolutum and examined 30 days later, it was found that 77% of the snails had a single infection with E. revolutum, 16 % were infected with F. Gigantica only, and the remaining 7% had common infection. It was concluded that the dominant antagonism of E. revolutum over F. gigantica in L. rubiginosa and the reduction of fecundity and longevity ofsnails infected with E. revolutum could be useful for biological control of F. gigantica.

  13. Environmental and biological controls of urban tree transpiration in the Upper Midwest

    Science.gov (United States)

    Peters, E. B.; McFadden, J.; Montgomery, R.

    2009-12-01

    Urban trees provide a variety of ecosystem services to urban and suburban areas, including carbon uptake, climate amelioration, energy reduction, and stormwater management. Tree transpiration, in particular, modifies urban water budgets by providing an alternative pathway for water after rain events. The relative importance of environmental and biological controls on transpiration are poorly understood in urban areas, yet these controls are important for quantifying and scaling up the ecosystem services that urban trees provide at landscape and regional scales and predicting how urban ecosystems will respond to climate changes. The objectives of our study were to quantify the annual cycle of tree transpiration in an urban ecosystem and to determine how different urban tree species and plant functional types respond to environmental drivers. We continuously measured whole-tree transpiration using thermal dissipation sap flow at four urban forest stands that were broadly representative of the species composition and tree sizes found in a suburban residential neighborhood of Minneapolis-Saint Paul, Minnesota. A total of 40 trees, representing different species, plant functional types, successional stages, and xylem anatomy, were sampled throughout the 2007 and 2008 growing seasons (April-November). At each site we monitored soil moisture, air temperature, and relative humidity continuously, and we measured leaf area index weekly. Urban tree transpiration was strongly correlated with diurnal changes in vapor pressure deficit and photosynthetically active radiation and with seasonal changes in leaf area index. We found that plant functional type better explained species differences in transpiration per canopy area than either successional stage or xylem anatomy, largely due to differences in canopy structure between conifer and broad-leaf deciduous trees. We also observed inter-annual differences in transpiration rates due to a mid-season drought and longer growing

  14. The biological control of aquatic weeds in South Africa: Current status and future challenges

    Directory of Open Access Journals (Sweden)

    Martin P. Hill

    2017-03-01

    Full Text Available Background: Aquatic ecosystems in South Africa are prone to invasion by several invasive alien aquatic weeds, most notably, Eichhornia crassipes (Mart. Solms-Laub. (Pontederiaceae (water hyacinth; Pistia stratiotes L. (Araceae (water lettuce; Salvinia molesta D.S. Mitch. (Salviniaceae (salvinia; Myriophyllum aquaticum (Vell. Conc. Verd. (parrot’s feather; and Azolla filiculoides Lam. (Azollaceae (red water fern. Objective: We review the biological control programme on waterweeds in South Africa. Results: Our review shows significant reductions in the extent of invasions, and a return on biodiversity and socio-economic benefits through the use of this method. These studies provide justification for the control of widespread and emerging freshwater invasive alien aquatic weeds in South Africa. Conclusions: The long-term management of alien aquatic vegetation relies on the correct implementation of biological control for those species already in the country and the prevention of other species entering South Africa.

  15. 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.

  16. [Physicians' knowledge in Israel on the biology and control of head lice].

    Science.gov (United States)

    Mumcuoglu, Kosta Y; Mumcuoglu, Michael; Danilevich, Maria; Gilead, Leon

    2008-10-01

    Health providers such as physicians, nurses and pharmacists should be knowledgeable about the biology of head lice and the ways to control them effectively, in order to reduce the proportion of children infested with head lice. To evaluate the knowledge of physicians in Israel on the biology and epidemiology of lice, as well as their experience with infested individuals and their preferences for diagnosis, prophylaxis and control. An anonymous questionnaire with 37 questions was used. The first 20 questions addressed the general knowledge of physicians on lice biology and control, while the remaining 17 questions were related to their personal experience with lice and louse treatment. Out of 273 physicians interviewed 66.8% had good knowledge of lice, while the remaining 33.2% had some knowledge on lice. The difference between the groups of physicians with medium and good knowledge on lice was borderline significant (P=0.0722), with the dermatologists borderline significantly less knowledgeable than the rest (P=0.0765). Significant differences were found between those physicians with 4-6 or 11-20 years of professional experience and the remaining groups (twice Pbiology and control was higher than male physicians (39.4% and 29.4%, respectively), the differences were borderline significant (P=0.09). Pediatricians and dermatologists examined significantly more children than family physicians and general practitioners (P control of head louse infestations.

  17. Design, modeling and control of a pneumatically actuated manipulator inspired by biological continuum structures

    International Nuclear Information System (INIS)

    Kang, Rongjie; Zheng Tianjiang; Guglielmino, Emanuele; Caldwell, Darwin G; Branson, David T

    2013-01-01

    Biological tentacles, such as octopus arms, have entirely flexible structures and virtually infinite degrees of freedom (DOF) that allow for elongation, shortening and bending at any point along the arm length. The amazing dexterity of biological tentacles has driven the growing implementation of continuum manipulators in robotic systems. This paper presents a pneumatic manipulator inspired by biological continuum structures in some of their key features and functions, such as continuum morphology, intrinsic compliance and stereotyped motions with hyper redundant DOF. The kinematics and dynamics of the manipulator are formulated and identified, and a hierarchical controller taking inspiration from the structure of an octopus nervous system is used to relate desired stereotyped motions to individual actuator inputs. Simulations and experiments are carried out to validate the model and prototype where good agreement was found between the two. (paper)

  18. Optimal control of non-Markovian dynamics in a single-mode cavity strongly coupled to an inhomogeneously broadened spin ensemble

    Science.gov (United States)

    Krimer, Dmitry O.; Hartl, Benedikt; Mintert, Florian; Rotter, Stefan

    2017-10-01

    Ensembles of quantum-mechanical spins offer a promising platform for quantum memories, but proper functionality requires accurate control of unavoidable system imperfections. We present an efficient control scheme for a spin ensemble strongly coupled to a single-mode cavity based on a set of Volterra equations relying solely on weak classical control pulses. The viability of our approach is demonstrated in terms of explicit storage and readout sequences that will serve as a starting point towards the realization of more demanding full quantum-mechanical optimal control schemes.

  19. The quality control for biological-shield heavy concrete construction of nuclear power project

    International Nuclear Information System (INIS)

    Sun Hongjun; Ma Xinchao

    2012-01-01

    The paper introduces the function and characteristics of biological protective heavy-concrete, and its main application scope and role in Fangjiashan nuclear power project. From the aspects of raw material selection, mixing ratio test, heavy concrete production, the paper discusses the main control points of heavy concrete construction process, points out the basic characteristics of heavy concrete construction, and put forward measures to prevent density non-uniformity during heavy concrete construction and to control slump during transportation. Results prove that reasonable construction process control can assure the engineering quality. (authors)

  20. Energy-based control for a biologically inspired hexapod robot with rolling locomotion

    Directory of Open Access Journals (Sweden)

    Takuma Nemoto

    2015-04-01

    Full Text Available This paper presents an approach to control rolling locomotion on the level ground with a biologically inspired hexapod robot. For controlling rolling locomotion, a controller which can compensate energy loss with rolling locomotion of the hexapod robot is designed based on its dynamic model. The dynamic model describes the rolling locomotion which is limited to planar one by an assumption that the hexapod robot does not fall down while rolling and influences due to collision and contact with the ground, and it is applied for computing the mechanical energy of the hexapod robot and a plant for a numerical simulation. The numerical simulation of the rolling locomotion on the level ground verifies the effectiveness of the proposed controller. The simulation results show that the hexapod robot can perform the rolling locomotion with the proposed controller. In conclusion, it is shown that the proposed control approach is effective in achieving the rolling locomotion on the level ground.

  1. Biological control against the carob moth Ectomyelois ceratoniae in oases and in packing houses in Tunisia

    International Nuclear Information System (INIS)

    Dhouibi, M.H.; Cheikh, T.; Cherni, M.; Ben Moussa, I.; Hawlitsky, N.; Zaaraoui, H.; Krisaane, T.

    2000-01-01

    The carob moth, Ectomyelois ceratoniae Zeller is abundant in the Mediterranean countries. It attacks various dry fruit in cultures or in stored products, notably pomegranate, Punica granatum L.; date palm, Phoenis dactylifera L. plantations; citrus, Citrus spp., apricot, Prunus armeniaca L. and pistachios, Pistachio vera. We can find E. ceratoniae in the north as well as in the south of Tunisia, especially in central zones and Saharan areas where caterpillar infestations can reach 90% of pomegranate fruit and 20% of dates (Dhouibi 1991). To reduce this damage, several control methods have been experimented. Chemical control is the most effective means of control against pests. However, against this species, insecticides seem to be difficult and randomly used, due to the endophytic behaviour of the pyralid and the position of the fruit on the pomegranate tree. Moreover, this method has very ominous repercussions on biological cadence. Besides, it is necessary to look for other control means to allow the preservation of the ecosystem. In Tunisia, several efforts have been directed at biological control, by using local parasitoids and through usage of the bio-insecticides mainly Bacillus thuringiensis (Dhouibi 1992, 1994, Dhouibi and Jemmasi 1993). In order to substitute the chemical control and to strengthen the integrated control, other possibilities can be envisaged, for example, the genetic method or the autocidal control, that is, based on mass rearing and the substerile male releases into the natural population. For the purpose, it provokes the sterility to ulterior generations and evaluates the impact of irradiation on the different biological parameters of emerged adults from treated nymphs and their competitiveness. Dhouibi and Omran (1995) and Dhouibi and Tijani (1996) have studied the mass rearing of the carob moth pyralid on an artificial diet and the effect of different irradiation doses, especially a substerilising dose, on E. ceratoniae pupae

  2. Biological control against the carob moth Ectomyelois ceratoniae in oases and in packing houses in Tunisia

    Energy Technology Data Exchange (ETDEWEB)

    Dhouibi, M H; Cheikh, T; Cherni, M; Ben Moussa, I [Institut National Agronomique de Tunisie, Tunis Mahrajene (Tunisia); Hawlitsky, N [INRA Versaille (France); Zaaraoui, H; Krisaane, T [Groupement Interprofessionnel de Dattes de Toseur (Tunisia)

    2000-07-01

    The carob moth, Ectomyelois ceratoniae Zeller is abundant in the Mediterranean countries. It attacks various dry fruit in cultures or in stored products, notably pomegranate, Punica granatum L.; date palm, Phoenis dactylifera L. plantations; citrus, Citrus spp., apricot, Prunus armeniaca L. and pistachios, Pistachio vera. We can find E. ceratoniae in the north as well as in the south of Tunisia, especially in central zones and Saharan areas where caterpillar infestations can reach 90% of pomegranate fruit and 20% of dates (Dhouibi 1991). To reduce this damage, several control methods have been experimented. Chemical control is the most effective means of control against pests. However, against this species, insecticides seem to be difficult and randomly used, due to the endophytic behaviour of the pyralid and the position of the fruit on the pomegranate tree. Moreover, this method has very ominous repercussions on biological cadence. Besides, it is necessary to look for other control means to allow the preservation of the ecosystem. In Tunisia, several efforts have been directed at biological control, by using local parasitoids and through usage of the bio-insecticides mainly Bacillus thuringiensis (Dhouibi 1992, 1994, Dhouibi and Jemmasi 1993). In order to substitute the chemical control and to strengthen the integrated control, other possibilities can be envisaged, for example, the genetic method or the autocidal control, that is, based on mass rearing and the substerile male releases into the natural population. For the purpose, it provokes the sterility to ulterior generations and evaluates the impact of irradiation on the different biological parameters of emerged adults from treated nymphs and their competitiveness. Dhouibi and Omran (1995) and Dhouibi and Tijani (1996) have studied the mass rearing of the carob moth pyralid on an artificial diet and the effect of different irradiation doses, especially a substerilising dose, on E. ceratoniae pupae.

  3. Phylogenetics and genetic diversity of the Cotesia flavipes complex of parasitoid wasps (Hymenoptera: Braconidae), biological control agents of lepidopteran stemborers.

    Science.gov (United States)

    Muirhead, Kate A; Murphy, Nicholas P; Sallam, Nader; Donnellan, Stephen C; Austin, Andrew D

    2012-06-01

    The Cotesia flavipes complex of parasitoid wasps (Hymenoptera: Braconidae) are economically important for the biological control of lepidopteran stemboring pests associated with gramineous crops. Some members of the complex successfully parasitize numerous stemborer pest species, however certain geographic populations have demonstrated variation in the range of hosts that they parasitize. In addition, the morphology of the complex is highly conserved and considerable confusion surrounds the identity of species and host-associated biotypes. We generated nucleotide sequence data for two mtDNA genes (COI, 16S) and three anonymous nuclear loci (CfBN, CfCN, CfEN) for the C. flavipes complex. To analyze genetic variation and relationships among populations we used (1) concatenated mtDNA and nDNA data, (2) a nDNA multilocus network approach, and (3) two species tree inference methods, i.e. Bayesian estimation of species trees (BEST) and Bayesian inference of species trees from multilocus data with (*)BEAST. All phylogenetic analyses provide strong support for monophyly of the complex and the presence of at least four species, C. chilonis (from China and Japan), C. sesamiae (from Africa), C. flavipes (originating from the Indo-Asia region but introduced into Africa and the New World), and C. nonagriae (from Australia and Papua New Guinea). Haplotype diversity of geographic populations relates to historical biogeographic barriers and biological control introductions, and reflects previous reports of ecological variation in these species. Strong discordance was found between the mitochondrial and nuclear markers in the Papua New Guinea haplotypes, which may be an outcome of hybridization and introgression of C. flavipes and C. nonagriae. The position of Cotesia flavipes from Japan was not well supported in any analysis and was the sister taxon to C. nonagriae (mtDNA, (*)BEAST), C. flavipes (nDNA) or C. flavipes+C. nonagriae (BEST) and, may represent a cryptic species. The

  4. The extent to which ATP demand controls the glycolytic flux depends strongly on the organism and conditions for growth

    DEFF Research Database (Denmark)

    Købmann, Brian Jensen; Westerhoff, H.V.; Snoep, J.L.

    2002-01-01

    Using molecular genetics we have introduced uncoupled ATPase activity in two different bacterial species, Escherichia coli and Lactococcus lactis, and determined the elasticities of the growth rate and glycolytic flux towards the intracellular [ATP]/[ADP] ratio. During balanced growth in batch...... cultures of E. coli the ATP demand was found to have almost full control on the glycolytic flux (FCC=0.96) and the flux could be stimulated by 70%. In contrast to this, in L. lactis the control by ATP demand on the glycolytic flux was close to zero. However, when we used non-growing cells of L. lactis...... (which have a low glycolytic flux) the ATP demand had a high flux control and the flux could be stimulated more than two fold. We suggest that the extent to which ATP demand controls the glycolytic flux depends on how much excess capacity of glycolysis is present in the cells....

  5. Biological control agents for suppression of post-harvest diseases of potatoes: strategies on discovery and development

    Science.gov (United States)

    As used in plant pathology, the term "biological control" or its short form “biocontrol” commonly refers to the decrease in the inoculum or the disease-producing activity of a pathogen accomplished through one or more organisms, including the host plant but excluding man. Biological control of plant...

  6. 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

  7. Protein-polymer nano-machines. Towards synthetic control of biological processes

    Directory of Open Access Journals (Sweden)

    Alexander Cameron

    2004-09-01

    Full Text Available Abstract The exploitation of nature's machinery at length scales below the dimensions of a cell is an exciting challenge for biologists, chemists and physicists, while advances in our understanding of these biological motifs are now providing an opportunity to develop real single molecule devices for technological applications. Single molecule studies are already well advanced and biological molecular motors are being used to guide the design of nano-scale machines. However, controlling the specific functions of these devices in biological systems under changing conditions is difficult. In this review we describe the principles underlying the development of a molecular motor with numerous potential applications in nanotechnology and the use of specific synthetic polymers as prototypic molecular switches for control of the motor function. The molecular motor is a derivative of a TypeI Restriction-Modification (R-M enzyme and the synthetic polymer is drawn from the class of materials that exhibit a temperature-dependent phase transition. The potential exploitation of single molecules as functional devices has been heralded as the dawn of new era in biotechnology and medicine. It is not surprising, therefore, that the efforts of numerous multidisciplinary teams 12. have been focused in attempts to develop these systems. as machines capable of functioning at the low sub-micron and nanometre length-scales 3. However, one of the obstacles for the practical application of single molecule devices is the lack of functional control methods in biological media, under changing conditions. In this review we describe the conceptual basis for a molecular motor (a derivative of a TypeI Restriction-Modification enzyme with numerous potential applications in nanotechnology and the use of specific synthetic polymers as prototypic molecular switches for controlling the motor function 4.

  8. Agronomic aspects of strip intercropping lettuce with alyssum for biological control of aphids

    OpenAIRE

    Brennan, Eric B.

    2013-01-01

    Organic lettuce growers in California typically use insectary strips of alyssum (Lobularia maritima (L.) Desv.) to attract hoverflies (Syrphidae) that provide biological control of aphids. A two year study with transplanted organic romaine lettuce in Salinas, California investigated agronomic aspects of lettuce monoculture and lettuce-alyssum strip intercropping on beds in replacement intercropping treatments where alyssum transplants replaced 2 to 8% of the lettuce transplants, and in additi...

  9. 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

  10. Dynamic Analysis of a Phytoplankton-Fish Model with Biological and Artificial Control

    OpenAIRE

    Wang, Yapei; Zhao, Min; Pan, Xinhong; Dai, Chuanjun

    2014-01-01

    We investigate a nonlinear model of the interaction between phytoplankton and fish, which uses a pair of semicontinuous systems with biological and artificial control. First, the existence of an order-1 periodic solution to the system is analyzed using a Poincaré map and a geometric method. The stability conditions of the order-1 periodic solution are obtained by a theoretical mathematical analysis. Furthermore, based on previous analysis, we investigate the bifurcation in the order-1 periodi...

  11. Trichoderma-plant-pathogen interactions: advances in genetics of biological control.

    Science.gov (United States)

    Mukherjee, Mala; Mukherjee, Prasun K; Horwitz, Benjamin A; Zachow, Christin; Berg, Gabriele; Zeilinger, Susanne

    2012-12-01

    Trichoderma spp. are widely used in agriculture as biofungicides. Induction of plant defense and mycoparasitism (killing of one fungus by another) are considered to be the most important mechanisms of Trichoderma-mediated biological control. Understanding these mechanisms at the molecular level would help in developing strains with superior biocontrol properties. In this article, we review our current understanding of the genetics of interactions of Trichoderma with plants and plant pathogens.

  12. 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.

  13. Evaluation of biologic occupational risk control practices: quality indicators development and validation.

    Science.gov (United States)

    Takahashi, Renata Ferreira; Gryschek, Anna Luíza F P L; Izumi Nichiata, Lúcia Yasuko; Lacerda, Rúbia Aparecida; Ciosak, Suely Itsuko; Gir, Elucir; Padoveze, Maria Clara

    2010-05-01

    There is growing demand for the adoption of qualification systems for health care practices. This study is aimed at describing the development and validation of indicators for evaluation of biologic occupational risk control programs. The study involved 3 stages: (1) setting up a research team, (2) development of indicators, and (3) validation of the indicators by a team of specialists recruited to validate each attribute of the developed indicators. The content validation method was used for the validation, and a psychometric scale was developed for the specialists' assessment. A consensus technique was used, and every attribute that obtained a Content Validity Index of at least 0.75 was approved. Eight indicators were developed for the evaluation of the biologic occupational risk prevention program, with emphasis on accidents caused by sharp instruments and occupational tuberculosis prevention. The indicators included evaluation of the structure, process, and results at the prevention and biologic risk control levels. The majority of indicators achieved a favorable consensus regarding all validated attributes. The developed indicators were considered validated, and the method used for construction and validation proved to be effective. Copyright (c) 2010 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Mosby, Inc. All rights reserved.

  14. Towards Biological Control of Kudzu Through an Improved Understanding of Insect-Kudzu Interactions

    Energy Technology Data Exchange (ETDEWEB)

    Orr, D.; Barber, G.; DeBarr, G.; Thornton, M.

    2001-08-03

    The authors evaluated various approaches to the biological control of kudzu and exotic weed that infests the SRS. A large number of native pollinators were found to be attracted to kudzu. The viability of seed was found to be low, between 2% and 11%. This is the result of native Hemiptera. The results suggest that seed feeding insects should not be targeted for importation. Both kudzu and soybeans had the same level of abundance and diversity of herbivore insects and the same levels of defoliation. No vine or root damaging species were found. Efforts should be targeted to the latter insects to control kudzu.

  15. Quality control in the neutron activation analysis of biological markers for selenium in epidemiological investigations

    International Nuclear Information System (INIS)

    Morris, J.S.; Ngwenyama, R.A.; Guthrie, J.M.; Brockman, J.D.; Spate, V.L.; Robertson, J.D.

    2008-01-01

    Instrumental neutron activation analysis is routinely used at the MURR to quantify selenium in prospectively-collected biologic markers including blood serum and toenails. These specimens are typically collected from well-defined cohort populations participating in investigations assessing selenium intake and incidence of chronic disease endpoints. These epidemiological investigations, whether observational (case-control) or clinical (intervention), typically generate thousands of samples. The purpose of this paper is to assess, through evaluation of quality control results, if the achievable accuracy and precision in the measurement of selenium using NAA is adequate to determine a relative risk of 1.2 at high confidence in epidemiological studies. (author)

  16. Acousto-optic control of internal acoustic reflection in tellurium dioxide crystal in case of strong elastic energy walkoff [Invited].

    Science.gov (United States)

    Voloshinov, Vitaly; Polikarpova, Nataliya; Ivanova, Polina; Khorkin, Vladimir

    2018-04-01

    Peculiar cases of acoustic wave propagation and reflection may be observed in strongly anisotropic acousto-optical crystals. A tellurium dioxide crystal serves as a prime example of such media, since it possesses record indexes of acoustic anisotropy. We studied one of the unusual scenarios of acoustic incidence and reflection from a free crystal-vacuum boundary in paratellurite. The directions of the acoustic waves in the (001) plane of the crystal were determined, and their basic characteristics were calculated. The carried-out acousto-optic experiment at the wavelength of light 532 nm and the acoustic frequency 73 MHz confirmed the theoretical predictions. The effects examined in the paper include the acoustic wave propagation with the record walkoff angle 74°. We also observed the incidence of the wave on the boundary at the angle exceeding 90°. Finally, we registered the close-to-back reflection of acoustic energy following the incidence. One of the stunning aspects is the distribution of energy between the incident and the back-reflected wave. The unusual features of the acoustic wave reflections pointed out in the paper are valuable for their possible applications in acousto-optic devices.

  17. Is the efficacy of biological control against plant diseases likely to be more durable than that of chemical pesticides?

    Directory of Open Access Journals (Sweden)

    Marc eBardin

    2015-07-01

    Full Text Available The durability of a control method for plant protection is defined as the persistence of its efficacy in space and time. It depends on (i the selection pressure exerted by it on populations of plant pathogens and (ii on the capacity of these pathogens to adapt to the control method. Erosion of effectiveness of conventional plant protection methods has been widely studied in the past. For example, apparition of resistance to chemical pesticides in plant pathogens or pests has been extensively documented. The durability of biological control has often been assumed to be higher than that of chemical control. Results concerning pest management in agricultural systems have shown that this assumption may not always be justified. Resistance of various pests to one or several toxins of Bacillus thuringensis and apparition of resistance of the codling moth Cydia pomonella to the Cydia pomonella granulovirus have, for example, been described. In contrast with the situation for pests, the durability of biological control of plant diseases has hardly been studied and no scientific reports proving the loss of efficiency of biological control agents against plant pathogens in practice has been published so far. Knowledge concerning the possible erosion of effectiveness of biological control is essential to ensure a durable efficacy of biological control agents on target plant pathogens. This knowledge will result in identifying risk factors that can foster the selection of strains of plant pathogens resistant to biological control agents. It will also result in identifying types of biological control agents with lower risk of efficacy loss i.e. modes of action of biological control agents that does not favor the selection of resistant isolates in natural populations of plant pathogens. An analysis of the scientific literature was then conducted to assess the potential for plant pathogens to become resistant to biological control agents.

  18. Integration of Plant Defense Traits with Biological Control of Arthropod Pests: Challenges and Opportunities.

    Science.gov (United States)

    Peterson, Julie A; Ode, Paul J; Oliveira-Hofman, Camila; Harwood, James D

    2016-01-01

    Crop plants exhibit a wide diversity of defensive traits and strategies to protect themselves from damage by herbivorous pests and disease. These defensive traits may be naturally occurring or artificially selected through crop breeding, including introduction via genetic engineering. While these traits can have obvious and direct impacts on herbivorous pests, many have profound effects on higher trophic levels, including the natural enemies of herbivores. Multi-trophic effects of host plant resistance have the potential to influence, both positively and negatively, biological control. Plant defense traits can influence both the numerical and functional responses of natural enemies; these interactions can be semiochemically, plant toxin-, plant nutrient-, and/or physically mediated. Case studies involving predators, parasitoids, and pathogens of crop pests will be presented and discussed. These diverse groups of natural enemies may respond differently to crop plant traits based on their own unique biology and the ecological niches they fill. Genetically modified crop plants that have been engineered to express transgenic products affecting herbivorous pests are an additional consideration. For the most part, transgenic plant incorporated protectant (PIP) traits are compatible with biological control due to their selective toxicity to targeted pests and relatively low non-target impacts, although transgenic crops may have indirect effects on higher trophic levels and arthropod communities mediated by lower host or prey number and/or quality. Host plant resistance and biological control are two of the key pillars of integrated pest management; their potential interactions, whether they are synergistic, complementary, or disruptive, are key in understanding and achieving sustainable and effective pest management.

  19. Integration of plant defense traits with biological control of arthropod pests: challenges and opportunities

    Directory of Open Access Journals (Sweden)

    Julie A Peterson

    2016-11-01

    Full Text Available Crop plants exhibit a wide diversity of defensive traits and strategies to protect themselves from damage by herbivorous pests and disease. These defensive traits may be naturally occurring or artificially selected through crop breeding, including introduction via genetic engineering. While these traits can have obvious and direct impacts on herbivorous pests, many have profound effects on higher trophic levels, including the natural enemies of herbivores. Multi-trophic effects of host plant resistance have the potential to influence, both positively and negatively, biological control. Plant defense traits can influence both the numerical and functional responses of natural enemies; these interactions can be semiochemically-, plant toxin-, plant nutrient-, and/or physically-mediated. Case studies involving predators, parasitoids, and pathogens of crop pests will be presented and discussed. These diverse groups of natural enemies may respond differently to crop plant traits based on their own unique biology and the ecological niches they fill. Genetically modified crop plants that have been engineered to express transgenic products affecting herbivorous pests are an additional consideration. For the most part, transgenic plant incorporated protectant (PIP traits are compatible with biological control due to their selective toxicity to targeted pests and relatively low non-target impacts, although transgenic crops may have indirect effects on higher trophic levels and arthropod communities mediated by lower host or prey number and/or quality. Host plant resistance and biological control are two of the key pillars of integrated pest management; their potential interactions, whether they are synergistic, complementary, or disruptive, are key in understanding and achieving sustainable and effective pest management.

  20. The Florey lecture, 1983. Biological control, as exemplified by smallpox eradication and myxomatosis.

    Science.gov (United States)

    Fenner, F

    1983-06-22

    Biological control is an important method of dealing with plant and insect pests. The control of rabbits by myxomatosis and the eradication of smallpox by vaccination are unusual examples of biological control, in that they involve a vertebrate and a viral pest respectively. Myxomatosis is a benign disease in Sylvilagus rabbits in South America which is transmitted mechanically by mosquitoes. In the European rabbit, Oryctolagus, which is a pest in Australia and England, the virus from Sylvilagus produces a generalized disease that is almost always lethal. Myxomatosis was deliberately introduced into Australia in 1950 and into Europe in 1952. It was at first spectacularly successful in controlling the rabbit pest, but biological adjustments occurred in the virulence of the virus and the genetic resistances of rabbits. After 30 years of interaction, natural selection has resulted in a balance at a fairly high level of viral virulence. Smallpox has been a major scourge of mankind for over 1500 years. It spread from Asia to Europe in the Middle ages and from Europe to Africa and the Americas in the 15th and 16th centuries. Jenner's cowpox vaccine provided a method of control that reduced the severity of the disease during the 19th century but failed to eliminate the disease from many countries before the 1930s. Thereafter it was eradicated from Europe and North America, but remained endemic in South America, Africa and Asia. In 1967 it was still endemic in 33 countries and W.H.O. established a programme for global eradication within 10 years. The goal was achieved in 1977. Problems of the eradication programme and reasons for its success will be described.

  1. Biological control of white mold by Trichoderma harzianum in common bean under field conditions

    Directory of Open Access Journals (Sweden)

    Daniel Diego Costa Carvalho

    2015-12-01

    Full Text Available Abstract: The objective of this work was to evaluate Trichoderma harzianum isolates for biological control of white mold in common bean (Phaseolus vulgaris. Five isolates were evaluated for biocontrol of white mold in 'Perola' common bean under field conditions, in the 2009 and 2010 crop seasons. A commercial isolate (1306 and a control treatment were included. Foliar applications at 2x109 conidia mL-1 were performed at 42 and 52 days after sowing (DAS, in 2009, and at 52 DAS in 2010. The CEN287, CEN316, and 1306 isolates decreased the number of Sclerotinia sclerotiorum apothecia per square meter in comparison to the control, in both crop seasons. CEN287, CEN316, and 1306 decreased white mold severity during the experimental period, when compared to the control.

  2. Photo-Responsive Graphene and Carbon Nanotubes to Control and Tackle Biological Systems

    Science.gov (United States)

    Cardano, Francesca; Frasconi, Marco; Giordani, Silvia

    2018-01-01

    Photo-responsive multifunctional nanomaterials are receiving considerable attention for biological applications because of their unique properties. The functionalization of the surface of carbon nanotubes (CNTs) and graphene, among other carbon based nanomaterials, with molecular switches that exhibit reversible transformations between two or more isomers in response to different kind of external stimuli, such as electromagnetic radiation, temperature and pH, has allowed the control of the optical and electrical properties of the nanomaterial. Light-controlled molecular switches, such as azobenzene and spiropyran, have attracted a lot of attention for nanomaterial's functionalization because of the remote modulation of their physicochemical properties using light stimulus. The enhanced properties of the hybrid materials obtained from the coupling of carbon based nanomaterials with light-responsive switches has enabled the fabrication of smart devices for various biological applications, including drug delivery, bioimaging and nanobiosensors. In this review, we highlight the properties of photo-responsive carbon nanomaterials obtained by the conjugation of CNTs and graphene with azobenzenes and spiropyrans molecules to investigate biological systems, devising possible future directions in the field. PMID:29707534

  3. 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.

  4. Genetic Variation and Biological Control of Fusarium graminearum Isolated from Wheat in Assiut-Egypt

    Directory of Open Access Journals (Sweden)

    Amer F. Mahmoud

    2016-04-01

    Full Text Available Fusarium graminearum Schwabe causes Fusarium head blight (FHB, a devastating disease that leads to extensive yield and quality loss of wheat and other cereal crops. Twelve isolates of F. graminearum were collected from naturally infected spikes of wheat from Assiut Egypt. These isolates were compared using SRAP. The results indicated distinct genetic groups exist within F. graminearum, and demonstrated that these groups have different biological properties, especially with respect to their pathogenicity on wheat. There were biologically significant differences between the groups; with group (B isolates being more aggressive towards wheat than groups (A and (C. Furthermore, Trichoderma harzianum (Rifai and Bacillus subtilis (Ehrenberg which isolated from wheat kernels were screened for antagonistic activity against F. graminearum. They significantly reduced the growth of F. graminearum colonies in culture. In order to gain insight into biological control effect in situ, highly antagonistic isolates of T. harzianum and B. subtilis were selected, based on their in vitro effectiveness, for greenhouse test. It was revealed that T. harzianum and B. subtilis significantly reduced FHB severity. The obtained results indicated that T. harzianum and B. subtilis are very effective biocontrol agents that offer potential benefit in FHB and should be harnessed for further biocontrol applications. The accurate analysis of genetic variation and studies of population structures have significant implications for understanding the genetic traits and disease control programs in wheat. This is the first known report of the distribution and genetic variation of F. graminearum on wheat spikes in Assiut Egypt.

  5. Photo-Responsive Graphene and Carbon Nanotubes to Control and Tackle Biological Systems

    Science.gov (United States)

    Cardano, Francesca; Frasconi, Marco; Giordani, Silvia

    2018-04-01

    Photo-responsive multifunctional nanomaterials are receiving considerable attention for biological applications because of their unique properties. The functionalization of the surface of carbon nanotubes (CNTs) and graphene, among other carbon based nanomaterials, with molecular switches that exhibit reversible transformations between two or more isomers in response to different kind of external stimuli, such as electromagnetic radiation, temperature and pH, has allowed the control of the optical and electrical properties of the nanomaterial. Light-controlled molecular switches, such as azobenzene and spiropyran, have attracted a lot of attention for nanomaterial’s functionalization because of the remote modulation of their physicochemical properties using light stimulus. The enhanced properties of the hybrid materials obtained from the coupling of carbon based nanomaterials with light-responsive switches has enabled the fabrication of smart devices for various biological applications, including drug delivery, bioimaging and nanobiosensors. In this review, we highlight the properties of photo-responsive carbon nanomaterials obtained by the conjugation of CNTs and graphene with azobenzenes and spiropyrans molecules to investigate biological systems, devising possible future directions in the field.

  6. Spatio-temporal coherent control of atomic systems: weak to strong field transition and breaking of symmetry in 2D maps

    Energy Technology Data Exchange (ETDEWEB)

    Suchowski, H; Natan, A; Bruner, B D; Silberberg, Y [Physics of Complex Systems, Weizmann Institute of Science, Rehovot (Israel)], E-mail: haim.suchowski@weizmann.ac.il

    2008-04-14

    Coherent control of resonant and non-resonant two-photon absorption processes was examined using a spatio-temporal pulse-shaping technique. By utilizing a combination of temporal focusing and femtosecond pulse-shaping techniques, we spatially control multiphoton absorption processes in a completely deterministic manner. Distinctive symmetry properties emerge through two-dimensional mapping of spatio-temporal data. These symmetries break down in the transition to strong fields, revealing details of strong-field effects such as power broadenings and dynamic Stark shifts. We also present demonstrations of chirp-dependent population transfer in atomic rubidium, as well as the spatial separation of resonant and non-resonant excitation pathways in atomic caesium.

  7. Spatio-temporal coherent control of atomic systems: weak to strong field transition and breaking of symmetry in 2D maps

    International Nuclear Information System (INIS)

    Suchowski, H; Natan, A; Bruner, B D; Silberberg, Y

    2008-01-01

    Coherent control of resonant and non-resonant two-photon absorption processes was examined using a spatio-temporal pulse-shaping technique. By utilizing a combination of temporal focusing and femtosecond pulse-shaping techniques, we spatially control multiphoton absorption processes in a completely deterministic manner. Distinctive symmetry properties emerge through two-dimensional mapping of spatio-temporal data. These symmetries break down in the transition to strong fields, revealing details of strong-field effects such as power broadenings and dynamic Stark shifts. We also present demonstrations of chirp-dependent population transfer in atomic rubidium, as well as the spatial separation of resonant and non-resonant excitation pathways in atomic caesium

  8. Biological control of Botrytis gray mould on tomato cultivated in greenhouse.

    Science.gov (United States)

    Fiume, F; Fiume, G

    2006-01-01

    Research was carried out to evaluate the effectiveness of the biological control of the Botrytis gray mould, caused by Botrytis cinerea Pers., one of the most important fungal diseases of the tomato (Lycopersicon esculentum Mill.). Biological control was performed by using Trichoderma harzianum Rifai, an antagonist that is a naturally occurring fungus found on some plants and in the soil worldwide. Trichoderma spp. are fungi diffused in nearly all agricultural soils and in other environments such as decaying wood. The object of this research is to find control strategies to reduce chemical treatments that cause damage to the environment and increase the pathogen resistance, applying the biological control by using T. harzianum against B. cinerea. A commercial product containing a natural isolate of T. harzianum is trichodex (Makhteshim Chemical Works, LTD). The research was performed in laboratory and in greenhouse. In laboratory, radial growth reduction of B. cinerea, in presence of T. harzianum, was calculated in relation to the growth of the pathogen control, by using a specific formula that measures the percentage of the inhibition of the radial mycelial growth. In greenhouse, starting from the tomato fruit setting, the research was carried out comparing, by a randomized complete block experiment design, replicated four times, the following treatments:1) untreated control; 2) pyrimethanil (400 g/L of a.i.), at 200 cc/hL of c.i. (pyrimidine fungicides); 3) trichodex at 100g/hL (1 kg/ha); 4) trichodex at 200 g/hL (2 kg/ha); 5) trichodex at 400 g/hL (4 kg/ha). Before fruit setting, the plots were all treated against Botrytis gray mould with iprodione 50% (100 g/hL), procymidone 50% (100 g/hL) and switch (Novartis plant protection) at 80 g/hL. In dual culture, the inhibition of B. cinerea radial mycelial growth was 76%. No inhibition halo was observed between B. cinerea and T. harzianum colonies but, after 3 days, the pathogen colony radius resulted no more than 1

  9. 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.

  10. Mites and spiders act as biological control agent to sand flies

    Directory of Open Access Journals (Sweden)

    Diwakar Singh Dinesh

    2014-02-01

    Full Text Available Objective: To find out natural biological control agents of sand flies vector of kala azar in Bihar, India. Methods: Sand flies collected from the field using CDC light trap installing overnight to the collection site scrutitinized for Phlebotomus argentipes, the established vector of visceral leishmaniasis. Blood fed adult females were confined in the insectary for its development of life cycle. During developmental stages 2nd to 4th instars larvae were examined closely by using compound microscope for mite infestation. Adult spider residing along with sand flies collected in trap were kept in cage along with sand flies and their activities were watched closely and recorded by video and picture. Results: Mites were found predating 2nd to 4th instars larvae only under the laboratory conditions and lowering down the population of sand flies up to basal level within 15 d after infestation. One specific spider was found eating blood fed female sand flies kept inside the cage (n=50 attacking on lower part of thoracic region to kill the sand fly and ate desired soft part. Conclusions: Both predators, mites and spiders are acting as biological control agents to larvae and adults of sand flies respectively resulting variable density of vectors due to variable association with these predators and also cause lowering the transmission of the disease as hidden natural controlling agent of sand flies. The extensive study will be of immense help in controlling sand flies without use of environmental pollutant i.e. chemical insecticide.

  11. Controlled power delivery for super-resolution imaging of biological samples using digital micromirror device

    Science.gov (United States)

    Valiya Peedikakkal, Liyana; Cadby, Ashley

    2017-02-01

    Localization based super resolution images of a biological sample is generally achieved by using high power laser illumination with long exposure time which unfortunately increases photo-toxicity of a sample, making super resolution microscopy, in general, incompatible with live cell imaging. Furthermore, the limitation of photobleaching reduces the ability to acquire time lapse images of live biological cells using fluorescence microscopy. Digital Light Processing (DLP) technology can deliver light at grey scale levels by flickering digital micromirrors at around 290 Hz enabling highly controlled power delivery to samples. In this work, Digital Micromirror Device (DMD) is implemented in an inverse Schiefspiegler telescope setup to control the power and pattern of illumination for super resolution microscopy. We can achieve spatial and temporal patterning of illumination by controlling the DMD pixel by pixel. The DMD allows us to control the power and spatial extent of the laser illumination. We have used this to show that we can reduce the power delivered to the sample to allow for longer time imaging in one area while achieving sub-diffraction STORM imaging in another using higher power densities.

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

    Directory of Open Access Journals (Sweden)

    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.

  13. In vitro susceptibility of nematophagous fungi to antiparasitic drugs: interactions and implications for biological control

    Directory of Open Access Journals (Sweden)

    J. N. Vieira

    Full Text Available Abstract The fast anthelmintic resistance development has shown a limited efficiency in the control of animal’s endoparasitosis and has promoted research using alternative control methods. The use of chemicals in animal anthelmintic treatment, in association with nematophagous fungi used for biological control, is a strategy that has proven to be effective in reducing the nematode population density in farm animals. This study aims to verify the in vitro susceptibility of the nematophagous fungi Arthrobotrys oligospora, Duddingtonia flagrans and Paecilomyces lilacinus against the antiparasitic drugs albendazole, thiabendazole, ivermectin, levamisole and closantel by using the Minimum Inhibitory Concentration (MIC. MICs ranged between 4.0 and 0.031 µg/mL for albendazole, thiabendazole and ivermectin, between 0.937 and 0.117 µg/mL for levamisole, and between 0.625 and 0.034 µg/mL for closantel. The results showed that all antiparasitic drugs had an in vitro inhibitory effect on nematophagous fungi, which could compromise their action as agents of biological control. D. flagrans was the most susceptible species to all drugs.

  14. Controls of nitrite oxidation in ammonia-removing biological air filters

    DEFF Research Database (Denmark)

    Juhler, Susanne; Ottosen, Lars Ditlev Mørck; Nielsen, Lars Peter

    2008-01-01

    in accumulation of nitrate rather than nitrite and a significant decline in pH. As a consequence, ammonia is removed more efficiently, but heterotrophic oxidation of odorous compounds might be inhibited.  To identify the controlling mechanisms of nitrite oxidation, full-scale biological air filters were...... activity resulting in a lowered pH and thus a decreased FA concentration, promoting further growth of NOB. Yet, in some cases a situation with a nitrate-to-nitrite ratio of 1 and moderate pH remained stable even under varying air load and water supply, suggesting that additional mechanisms were involved......In biological air filters ammonia is removed due to the action of Ammonia Oxidizing Bacteria (AOB) resulting in nitrite accumulation exceeding 100 mM. Among filters treating exhaust air from pig facilities successful establishment of Nitrite Oxidizing Bacteria (NOB) sometimes occurs, resulting...

  15. Analysis of double stub tuner control stability in a phased array antenna with strong cross-coupling

    Energy Technology Data Exchange (ETDEWEB)

    Wallace, G.M., E-mail: wallaceg@mit.edu [MIT Plasma Science and Fusion Center, Cambridge, MA 02139 (United States); Hillairet, J. [CEA-IRFM, Saint-Paul-lez-Durance (France); Koert, P.; Lin, Y.; Shiraiwa, S.; Wukitch, S.J. [MIT Plasma Science and Fusion Center, Cambridge, MA 02139 (United States)

    2014-11-15

    Highlights: • A novel method for reducing reflection coefficients for LHCD launchers is proposed and evaluated. • Numerical models of antenna behavior with stub tuning are analyzed. • The system is found to be stable under most realistic operating conditions. - Abstract: Active stub tuning with a fast ferrite tuner (FFT) has greatly increased the effectiveness of fusion ion cyclotron range of frequency (ICRF) systems (50–100 MHz) by allowing for the antenna system to respond dynamically to changes in the plasma load impedance such as during the L–H transition or edge localized modes (ELMs). A high power waveguide double-stub tuner is under development for use with the Alcator C-Mod lower hybrid current drive (LHCD) system at 4.6 GHz. The amplitude and relative phase shift between adjacent columns of an LHCD antenna are critical for control of the launched n{sub ||} spectrum. Adding a double-stub tuning network will perturb the phase and amplitude of the forward wave particularly if the unmatched reflection coefficient is high. This effect can be compensated by adjusting the phase of the low power microwave drive for each klystron amplifier. Cross-coupling of the reflected power between columns of the launcher must also be considered. The problem is simulated by cascading a scattering matrix for the plasma provided by a linear coupling model with the measured launcher scattering matrix and that of the FFTs. The solution is advanced in an iterative manner similar to the time-dependent behavior of the real system. System performance is presented under a range of edge density conditions from under-dense to over-dense and a range of launched n{sub ||}. Simulations predict power reflection coefficients (Γ{sup 2}) of less than 1% with no contamination of the n{sub ||} spectrum. Instability of the FFT tuning network can be problematic for certain plasma conditions and relative phasings, but reducing the control gain of the FFT network stabilizes the system.

  16. The Diuretic Action of Weak and Strong Alcoholic Beverages in Elderly Men: A Randomized Diet-Controlled Crossover Trial.

    Science.gov (United States)

    Polhuis, Kristel C M M; Wijnen, Annemarthe H C; Sierksma, Aafje; Calame, Wim; Tieland, Michael

    2017-06-28

    With ageing, there is a greater risk of dehydration. This study investigated the diuretic effect of alcoholic beverages varying in alcohol concentration in elderly men. Three alcoholic beverages (beer (AB), wine (AW), and spirits (S)) and their non-alcoholic counterparts (non-alcoholic beer (NAB), non-alcoholic wine (NAW), and water (W)) were tested in a diet-controlled randomized crossover trial. For the alcoholic beverages, alcohol intake equaled a moderate amount of 30 g. An equal volume of beverage was given for the non-alcoholic counterpart. After consumption, the urine output was collected every hour for 4 h and the total 24 h urine output was measured. AW and S resulted in a higher cumulative urine output compared to NAW and W during the first 4 h (effect size: 0.25 mL p 0.40, p > 0.10). AB and NAB did not differ at any time point (effect size: -0.02 mL p > 0.70). For urine osmolality, and the sodium and potassium concentration, the findings were in line. In conclusion, only moderate amounts of stronger alcoholic beverages, such as wine and spirits, resulted in a short and small diuretic effect in elderly men.

  17. Biologically Based Methods for Control of Fumonisin-Producing Fusarium Species and Reduction of the Fumonisins.

    Science.gov (United States)

    Alberts, Johanna F; van Zyl, Willem H; Gelderblom, Wentzel C A

    2016-01-01

    Infection by the fumonisin-producing Fusarium spp. and subsequent fumonisin contamination of maize adversely affect international trade and economy with deleterious effects on human and animal health. In developed countries high standards of the major food suppliers and retailers are upheld and regulatory controls deter the importation and local marketing of fumonisin-contaminated food products. In developing countries regulatory measures are either lacking or poorly enforced, due to food insecurity, resulting in an increased mycotoxin exposure. The lack and poor accessibility of effective and environmentally safe control methods have led to an increased interest in practical and biological alternatives to reduce fumonisin intake. These include the application of natural resources, including plants, microbial cultures, genetic material thereof, or clay minerals pre- and post-harvest. Pre-harvest approaches include breeding for resistant maize cultivars, introduction of biocontrol microorganisms, application of phenolic plant extracts, and expression of antifungal proteins and fumonisin degrading enzymes in transgenic maize cultivars. Post-harvest approaches include the removal of fumonisins by natural clay adsorbents and enzymatic degradation of fumonisins through decarboxylation and deamination by recombinant carboxylesterase and aminotransferase enzymes. Although, the knowledge base on biological control methods has expanded, only a limited number of authorized decontamination products and methods are commercially available. As many studies detailed the use of natural compounds in vitro, concepts in reducing fumonisin contamination should be developed further for application in planta and in the field pre-harvest, post-harvest, and during storage and food-processing. In developed countries an integrated approach, involving good agricultural management practices, hazard analysis and critical control point (HACCP) production, and storage management, together with

  18. Biologically Based Methods for Control of Fumonisin-producing Fusarium species and Reduction of the Fumonisins

    Directory of Open Access Journals (Sweden)

    Johanna Francina Alberts

    2016-04-01

    Full Text Available Infection by the fumonisin-producing Fusarium spp. and subsequent fumonisin contamination of maize adversely affect international trade and economy with deleterious effects on human and animal health. In developed countries high standards of the major food suppliers and retailers are upheld and regulatory controls deter the importation and local marketing of fumonisin-contaminated food products. In developing countries regulatory measures are either lacking or poorly enforced, due to food insecurity, resulting in an increased mycotoxin exposure. The lack and poor accessibility of effective and environmentally safe control methods have led to an increased interest in practical and biological alternatives to reduce fumonisin intake. These include the application of natural resources, including plants, microbial cultures, genetic material thereof or clay minerals pre- and postharvest. Pre-harvest approaches include breeding for resistant maize cultivars, introduction of biocontrol microorganisms, application of phenolic plant extracts, and expression of antifungal proteins and fumonisin degrading enzymes in transgenic maize cultivars. Postharvest approaches include the removal of fumonisins by natural clay adsorbents and enzymatic degradation of fumonisins through decarboxylation and deamination by recombinant carboxylesterase and aminotransferase enzymes. Although the knowledge base on biological control methods has expanded, only a limited number of authorized decontamination products and methods are commercially available. As many studies detailed the use of natural compounds in vitro, concepts in reducing fumonisin contamination should be developed further for application in planta and in the field pre-harvest, postharvest, and during storage and food-processing. In developed countries an integrated approach, involving good agricultural management practices, hazard analysis and critical control point (HACCP production and storage management

  19. Biologically Based Methods for Control of Fumonisin-Producing Fusarium Species and Reduction of the Fumonisins

    Science.gov (United States)

    Alberts, Johanna F.; van Zyl, Willem H.; Gelderblom, Wentzel C. A.

    2016-01-01

    Infection by the fumonisin-producing Fusarium spp. and subsequent fumonisin contamination of maize adversely affect international trade and economy with deleterious effects on human and animal health. In developed countries high standards of the major food suppliers and retailers are upheld and regulatory controls deter the importation and local marketing of fumonisin-contaminated food products. In developing countries regulatory measures are either lacking or poorly enforced, due to food insecurity, resulting in an increased mycotoxin exposure. The lack and poor accessibility of effective and environmentally safe control methods have led to an increased interest in practical and biological alternatives to reduce fumonisin intake. These include the application of natural resources, including plants, microbial cultures, genetic material thereof, or clay minerals pre- and post-harvest. Pre-harvest approaches include breeding for resistant maize cultivars, introduction of biocontrol microorganisms, application of phenolic plant extracts, and expression of antifungal proteins and fumonisin degrading enzymes in transgenic maize cultivars. Post-harvest approaches include the removal of fumonisins by natural clay adsorbents and enzymatic degradation of fumonisins through decarboxylation and deamination by recombinant carboxylesterase and aminotransferase enzymes. Although, the knowledge base on biological control methods has expanded, only a limited number of authorized decontamination products and methods are commercially available. As many studies detailed the use of natural compounds in vitro, concepts in reducing fumonisin contamination should be developed further for application in planta and in the field pre-harvest, post-harvest, and during storage and food-processing. In developed countries an integrated approach, involving good agricultural management practices, hazard analysis and critical control point (HACCP) production, and storage management, together with

  20. Biological insect control using Metarhizium anisopliae: morphological, molecular, and ecological aspects

    Directory of Open Access Journals (Sweden)

    Patricia Vieira Tiago

    2014-04-01

    Full Text Available Microbial control of insects is based on the rational use of pathogens to maintain environmentally balanced pest population levels, and Metarhizium anisopliae has been the most studied and most utilized fungal species for that purpose. The natural genetic variability of entomopathogenic fungi is considered one of the principal advantages of microbial insect control. The inter- and intraspecific variability and the genetic diversity and population structures of Metarhizium and other entomopathogenic fungi have been examined using ITS-RFLP, ISSR, and ISSP molecular markers. The persistence of M. anisopliae in the soil and its possible effects on the structures of resident microbial communities must be considered when selecting isolates for biological insect control.

  1. Surface modification of poly(dimethylsiloxane) for controlling biological cells' adhesion using a scanning radical microjet

    International Nuclear Information System (INIS)

    Tan, Helen M.L.; Fukuda, H.; Akagi, T.; Ichiki, T.

    2007-01-01

    A scanning radical microjet (SRMJ) equipment using oxygen microplasma has been developed and successfully applied for controlling biological cells' attachment on biocompatible polymer material, poly(dimethylsiloxane) (PDMS). The radical microjet has advantages in localized and high-rate surface treatment. Moreover, maskless hydrophilic patterning using SRMJ has been demonstrated to be applicable to patterned cell cultivation which is useful in emerging biotechnological field such as tissue engineering and cell-based biosensors. Since control of PDMS surface properties is an indispensable prerequisite for cells' attachment, effects of oxygen flow rates and treatment time on localized hydrophilic patterning of PDMS surfaces were first investigated for controlling HeLa cells' (human epitheloid carcinoma cell line) attachment. Relationships between surface conditions of treated PDMS films and attached cell density are also discussed based on surface properties analyzed using atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS)

  2. Towards building hybrid biological/in silico neural networks for motor neuroprosthetic control

    Directory of Open Access Journals (Sweden)

    Mehmet eKocaturk

    2015-08-01

    Full Text Available In this article, we introduce the Bioinspired Neuroprosthetic Design Environment (BNDE as a practical platform for the development of novel brain machine interface (BMI controllers which are based on spiking model neurons. We built the BNDE around a hard real-time system so that it is capable of creating simulated synapses from extracellularly recorded neurons to model neurons. In order to evaluate the practicality of the BNDE for neuroprosthetic control experiments, a novel, adaptive BMI controller was developed and tested using real-time closed-loop simulations. The present controller consists of two in silico medium spiny neurons which receive simulated synaptic inputs from recorded motor cortical neurons. In the closed-loop simulations, the recordings from the cortical neurons were imitated using an external, hardware-based neural signal synthesizer. By implementing a reward-modulated spike timing-dependent plasticity rule, the controller achieved perfect target reach accuracy for a two target reaching task in one dimensional space. The BNDE combines the flexibility of software-based spiking neural network (SNN simulations with powerful online data visualization tools and is a low-cost, PC-based and all-in-one solution for developing neurally-inspired BMI controllers. We believe the BNDE is the first implementation which is capable of creating hybrid biological/in silico neural networks for motor neuroprosthetic control and utilizes multiple CPU cores for computationally intensive real-time SNN simulations.

  3. Precision control of recombinant gene transcription for CHO cell synthetic biology.

    Science.gov (United States)

    Brown, Adam J; James, David C

    2016-01-01

    The next generation of mammalian cell factories for biopharmaceutical production will be genetically engineered to possess both generic and product-specific manufacturing capabilities that may not exist naturally. Introduction of entirely new combinations of synthetic functions (e.g. novel metabolic or stress-response pathways), and retro-engineering of existing functional cell modules will drive disruptive change in cellular manufacturing performance. However, before we can apply the core concepts underpinning synthetic biology (design, build, test) to CHO cell engineering we must first develop practical and robust enabling technologies. Fundamentally, we will require the ability to precisely control the relative stoichiometry of numerous functional components we simultaneously introduce into the host cell factory. In this review we discuss how this can be achieved by design of engineered promoters that enable concerted control of recombinant gene transcription. We describe the specific mechanisms of transcriptional regulation that affect promoter function during bioproduction processes, and detail the highly-specific promoter design criteria that are required in the context of CHO cell engineering. The relative applicability of diverse promoter development strategies are discussed, including re-engineering of natural sequences, design of synthetic transcription factor-based systems, and construction of synthetic promoters. This review highlights the potential of promoter engineering to achieve precision transcriptional control for CHO cell synthetic biology. Copyright © 2015. Published by Elsevier Inc.

  4. Biology and thermal requirements to Trichogramma spp. selection for Ecdytolopha aurantiana control

    International Nuclear Information System (INIS)

    Molina, Rosa M.S.; Parra, Jose R.P.

    2005-01-01

    The purpose of this work was to evaluate the potential of Trichogramma atopovirilia Oatman and Platner, 1983 and T. pretiosum Riley, 1879 as agents of control of Ecdytolopha aurantiana (Lima, 1927) (Lepidoptera: Tortricidae), an important Citrus pest in Sao Paulo State (South-East Brazil). In order to provide subsidies to programs of biological control with these parasitoids, studies of biology in different temperatures, thermal requirements and parasitism capacity were carried out. The temperatures (18, 20, 22, 25, 28, 30, and 32 deg C) did not affect the sex ratio, however, female longevity of both species was higher at 22 and 25 deg C. The temperature of 25 deg C tended to be more suitable to both emergency rate and female longevity. The egg-adult period for both Trichogramma species was inversely proportional to temperature. The thermal requirements of the two species were very close, about 108 DD (degree days). Neither the natural rearing host, E. aurantiana, nor the alternative host Anagasta kuehniella (Zeller, 1879) (Lepidoptera, Pyralidae), affected the number of parasitized eggs per Trichogramma female. The parasitism rate and the number of emerged adults per egg on E. aurantiana eggs were higher than on A. kuehniella eggs. However, the emergency rate was higher when the parasitoids were reared on A. kuehniella eggs. Both Trichogramma species could be tested in the field for citrus fruit borer control. The thermal requirements and the parasitism capacity also could be good parameters for selection of Trichogramma species/strains. (author)

  5. Effectiveness of biological control of Phytophthora capsici in pepper by Trichoderma asperellum strain T34

    Directory of Open Access Journals (Sweden)

    Guillem SEGARRA

    2013-05-01

    Full Text Available Pepper (Capsicum annuum L., one of the most widely grown vegetables worldwide, is susceptible to root rot caused by Phytophthora capsici. Many biocides have recently been banned in Europe because of human health and environmental concerns. Integrated pest management is a European priority, where biological control together with other agronomic practices should replace pesticide management of plant diseases in the future. Application of different concentrations of the fungus Trichoderma asperellum strain T34 (the in T34 Biocontrol® on incidence of disease caused by P. capsici in pepper was studied. Different methods of application of the microbial control agent and inoculation of the pathogen were examined. T34 and etridiazole (Terrazole® were compared for their ability to suppress P. capsici. T34 reduced disease in most of the assayed situations (up to 71% disease reduction, while etridiazole was effective only when applied at the same time as the pathogen. The results obtained are discussed on the basis of the different modes of action of T34 and etridiazole. T34 is a useful biological alternative to chemicals for the control of P. capsici in pepper.

  6. Early pest development and loss of biological control are associated with urban warming.

    Science.gov (United States)

    Meineke, Emily K; Dunn, Robert R; Frank, Steven D

    2014-11-01

    Climate warming is predicted to cause many changes in ectotherm communities, one of which is phenological mismatch, wherein one species' development advances relative to an associated species or community. Phenological mismatches already lead to loss of pollination services, and we predict that they also cause loss of biological control. Here, we provide evidence that a pest develops earlier due to urban warming but that phenology of its parasitoid community does not similarly advance. This mismatch is associated with greater egg production that likely leads to more pests on trees. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  7. Economic Benefits of Advanced Control Strategies in Biological Nutrient Removal Systems

    DEFF Research Database (Denmark)

    Carstensen, J.; Nielsen, M.K.; Harremoës, Poul

    1994-01-01

    little regards to the variations in load and biomass activity. However, these dynamics can be evaluated on-line using grey box models to describe the most important features of the hydraulic and biological processes. Simulation studies of plants with an alternating process have shown that control...... strategies incorporating information from the grey box models are capable of reducing the total nitrogen discharge as well as energy costs. These results have a major impact on both existing and future plants. In fact, it is expected that future plants can be reduced with 10-20 per cent in size...

  8. [The role of Marisa cornuarietis as a biological control agent and its economic and epidemiological implications].

    Science.gov (United States)

    Ferrer López, J R; Moné, H; Perera de Puga, G; Yong Cong, M

    1991-01-01

    It was determined that M. cornuarietis, a mollusk which has been used as agent for the biological control of the schistosomiasis hosts, may be a plague for rice fields. Each mollusk can consume 0.3 g of this plant in 24 hours, accounting for the destruction of 0.015 m2 of a rice field. On the other hand, it was observed that B. glabrata shows preference for the consumption of M. cornuarietis faeces. This fact favors the vector's growth and reproduction rate and at the same time decreases its mortality.

  9. Pythium root rot of common bean: biology and control methods. A review

    Directory of Open Access Journals (Sweden)

    Baudoin, JP.

    2012-01-01

    Full Text Available Pythium root rot constitutes a highly damaging constraint on the common bean, Phaseolus vulgaris L., grown in several areas of Eastern and Central Africa. Here, this food legume is cultivated intensively under poor conditions of crop rotation due to the exiguity of the land in the region. Yield losses of up to 70% in traditional local bean cultivars have been reported in Kenya and Rwanda. In this study, a detailed analysis of the biology and diversity of the Pythium genus was carried out in order to understand the mechanisms leading to the development of the disease. Various control methods for reducing the damage provoked by this disease were analyzed.

  10. Best practices for the use and exchange of invertebrate biological control genetic resources relevant for food and agriculture

    NARCIS (Netherlands)

    Mason, P.G.; Cock, M.J.W.; Barratt, B.I.P.; Klapwijk, J.N.; Lenteren, van J.C.; Brodeur, J.; Hoelmer, K.A.; Heimpel, G.E.

    2018-01-01

    The Nagoya Protocol is a supplementary agreement to the Convention on Biological Diversity that provides a framework for the effective implementation of the fair and equitable sharing of benefits arising out of the utilization of genetic resources, including invertebrate biological control agents.

  11. Anopheline Reproductive Biology: Impacts on Vectorial Capacity and Potential Avenues for Malaria Control.

    Science.gov (United States)

    Mitchell, Sara N; Catteruccia, Flaminia

    2017-12-01

    Vectorial capacity is a mathematical approximation of the efficiency of vector-borne disease transmission, measured as the number of new infections disseminated per case per day by an insect vector. Multiple elements of mosquito biology govern their vectorial capacity, including survival, population densities, feeding preferences, and vector competence. Intriguingly, biological pathways essential to mosquito reproductive fitness directly or indirectly influence a number of these elements. Here, we explore this complex interaction, focusing on how the interplay between mating and blood feeding in female Anopheles not only shapes their reproductive success but also influences their ability to sustain Plasmodium parasite development. Central to malaria transmission, mosquito reproductive biology has recently become the focus of research strategies aimed at malaria control, and we discuss promising new methods based on the manipulation of key reproductive steps. In light of widespread resistance to all public health-approved insecticides targeting mosquito reproduction may prove crucial to the success of malaria-eradication campaigns. Copyright © 2017 Cold Spring Harbor Laboratory Press; all rights reserved.

  12. Reliability of unstable periodic orbit based control strategies in biological systems

    International Nuclear Information System (INIS)

    Mishra, Nagender; Singh, Harinder P.; Hasse, Maria; Biswal, B.

    2015-01-01

    Presence of recurrent and statistically significant unstable periodic orbits (UPOs) in time series obtained from biological systems is now routinely used as evidence for low dimensional chaos. Extracting accurate dynamical information from the detected UPO trajectories is vital for successful control strategies that either aim to stabilize the system near the fixed point or steer the system away from the periodic orbits. A hybrid UPO detection method from return maps that combines topological recurrence criterion, matrix fit algorithm, and stringent criterion for fixed point location gives accurate and statistically significant UPOs even in the presence of significant noise. Geometry of the return map, frequency of UPOs visiting the same trajectory, length of the data set, strength of the noise, and degree of nonstationarity affect the efficacy of the proposed method. Results suggest that establishing determinism from unambiguous UPO detection is often possible in short data sets with significant noise, but derived dynamical properties are rarely accurate and adequate for controlling the dynamics around these UPOs. A repeat chaos control experiment on epileptic hippocampal slices through more stringent control strategy and adaptive UPO tracking is reinterpreted in this context through simulation of similar control experiments on an analogous but stochastic computer model of epileptic brain slices. Reproduction of equivalent results suggests that far more stringent criteria are needed for linking apparent success of control in such experiments with possible determinism in the underlying dynamics

  13. Reliability of unstable periodic orbit based control strategies in biological systems

    Energy Technology Data Exchange (ETDEWEB)

    Mishra, Nagender; Singh, Harinder P. [Department of Physics and Astrophysics, University of Delhi, Delhi 110007 (India); Hasse, Maria [Institut für Höchstleistungsrechnen, Universität Stuttgart, D-70569 Stuttgart (Germany); Biswal, B. [Cluster Innovation Center, University of Delhi, Delhi 110007 (India); Sri Venkateswara College, University of Delhi, Delhi 110021 (India)

    2015-04-15

    Presence of recurrent and statistically significant unstable periodic orbits (UPOs) in time series obtained from biological systems is now routinely used as evidence for low dimensional chaos. Extracting accurate dynamical information from the detected UPO trajectories is vital for successful control strategies that either aim to stabilize the system near the fixed point or steer the system away from the periodic orbits. A hybrid UPO detection method from return maps that combines topological recurrence criterion, matrix fit algorithm, and stringent criterion for fixed point location gives accurate and statistically significant UPOs even in the presence of significant noise. Geometry of the return map, frequency of UPOs visiting the same trajectory, length of the data set, strength of the noise, and degree of nonstationarity affect the efficacy of the proposed method. Results suggest that establishing determinism from unambiguous UPO detection is often possible in short data sets with significant noise, but derived dynamical properties are rarely accurate and adequate for controlling the dynamics around these UPOs. A repeat chaos control experiment on epileptic hippocampal slices through more stringent control strategy and adaptive UPO tracking is reinterpreted in this context through simulation of similar control experiments on an analogous but stochastic computer model of epileptic brain slices. Reproduction of equivalent results suggests that far more stringent criteria are needed for linking apparent success of control in such experiments with possible determinism in the underlying dynamics.

  14. Fuzzy logic for plant-wide control of biological wastewater treatment process including greenhouse gas emissions.

    Science.gov (United States)

    Santín, I; Barbu, M; Pedret, C; Vilanova, R

    2018-06-01

    The application of control strategies is increasingly used in wastewater treatment plants with the aim of improving effluent quality and reducing operating costs. Due to concerns about the progressive growth of greenhouse gas emissions (GHG), these are also currently being evaluated in wastewater treatment plants. The present article proposes a fuzzy controller for plant-wide control of the biological wastewater treatment process. Its design is based on 14 inputs and 6 outputs in order to reduce GHG emissions, nutrient concentration in the effluent and operational costs. The article explains and shows the effect of each one of the inputs and outputs of the fuzzy controller, as well as the relationship between them. Benchmark Simulation Model no 2 Gas is used for testing the proposed control strategy. The results of simulation results show that the fuzzy controller is able to reduce GHG emissions while improving, at the same time, the common criteria of effluent quality and operational costs. Copyright © 2018 ISA. Published by Elsevier Ltd. All rights reserved.

  15. 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.

  16. Decreased functional diversity and biological pest control in conventional compared to organic crop fields.

    Directory of Open Access Journals (Sweden)

    Jochen Krauss

    Full Text Available Organic farming is one of the most successful agri-environmental schemes, as humans benefit from high quality food, farmers from higher prices for their products and it often successfully protects biodiversity. However there is little knowledge if organic farming also increases ecosystem services like pest control. We assessed 30 triticale fields (15 organic vs. 15 conventional and recorded vascular plants, pollinators, aphids and their predators. Further, five conventional fields which were treated with insecticides were compared with 10 non-treated conventional fields. Organic fields had five times higher plant species richness and about twenty times higher pollinator species richness compared to conventional fields. Abundance of pollinators was even more than one-hundred times higher on organic fields. In contrast, the abundance of cereal aphids was five times lower in organic fields, while predator abundances were three times higher and predator-prey ratios twenty times higher in organic fields, indicating a significantly higher potential for biological pest control in organic fields. Insecticide treatment in conventional fields had only a short-term effect on aphid densities while later in the season aphid abundances were even higher and predator abundances lower in treated compared to untreated conventional fields. Our data indicate that insecticide treatment kept aphid predators at low abundances throughout the season, thereby significantly reducing top-down control of aphid populations. Plant and pollinator species richness as well as predator abundances and predator-prey ratios were higher at field edges compared to field centres, highlighting the importance of field edges for ecosystem services. In conclusion organic farming increases biodiversity, including important functional groups like plants, pollinators and predators which enhance natural pest control. Preventative insecticide application in conventional fields has only short

  17. Decreased functional diversity and biological pest control in conventional compared to organic crop fields.

    Science.gov (United States)

    Krauss, Jochen; Gallenberger, Iris; Steffan-Dewenter, Ingolf

    2011-01-01

    Organic farming is one of the most successful agri-environmental schemes, as humans benefit from high quality food, farmers from higher prices for their products and it often successfully protects biodiversity. However there is little knowledge if organic farming also increases ecosystem services like pest control. We assessed 30 triticale fields (15 organic vs. 15 conventional) and recorded vascular plants, pollinators, aphids and their predators. Further, five conventional fields which were treated with insecticides were compared with 10 non-treated conventional fields. Organic fields had five times higher plant species richness and about twenty times higher pollinator species richness compared to conventional fields. Abundance of pollinators was even more than one-hundred times higher on organic fields. In contrast, the abundance of cereal aphids was five times lower in organic fields, while predator abundances were three times higher and predator-prey ratios twenty times higher in organic fields, indicating a significantly higher potential for biological pest control in organic fields. Insecticide treatment in conventional fields had only a short-term effect on aphid densities while later in the season aphid abundances were even higher and predator abundances lower in treated compared to untreated conventional fields. Our data indicate that insecticide treatment kept aphid predators at low abundances throughout the season, thereby significantly reducing top-down control of aphid populations. Plant and pollinator species richness as well as predator abundances and predator-prey ratios were higher at field edges compared to field centres, highlighting the importance of field edges for ecosystem services. In conclusion organic farming increases biodiversity, including important functional groups like plants, pollinators and predators which enhance natural pest control. Preventative insecticide application in conventional fields has only short-term effects on aphid

  18. Dose prescription complexity versus tumor control probability in biologically conformal radiotherapy

    International Nuclear Information System (INIS)

    South, C. P.; Evans, P. M.; Partridge, M.

    2009-01-01

    The technical feasibility and potential benefits of voxel-based nonuniform dose prescriptions for biologically heterogeneous tumors have been widely demonstrated. In some cases, an ''ideal'' dose prescription has been generated by individualizing the dose to every voxel within the target, but often this voxel-based prescription has been discretized into a small number of compartments. The number of dose levels utilized and the methods used for prescribing doses and assigning tumor voxels to different dose compartments have varied significantly. The authors present an investigation into the relationship between the complexity of the dose prescription and the tumor control probability (TCP) for a number of these methods. The linear quadratic model of cell killing was used in conjunction with a number of modeled tumors heterogeneous in clonogen density, oxygenation, or proliferation. Models based on simple mathematical functions, published biological data, and biological image data were investigated. Target voxels were assigned to dose compartments using (i) simple rules based on the initial biological distribution, (ii) iterative methods designed to maximize the achievable TCP, or (iii) methods based on an ideal dose prescription. The relative performance of the simple rules was found to depend on the form of heterogeneity of the tumor, while the iterative and ideal dose methods performed comparably for all models investigated. In all cases the maximum achievable TCP was approached within the first few (typically two to five) compartments. Results suggest that irrespective of the pattern of heterogeneity, the optimal dose prescription can be well approximated using only a few dose levels but only if both the compartment boundaries and prescribed dose levels are well chosen.

  19. Healthy Foundations Study: a randomised controlled trial to evaluate biological embedding of early-life experiences.

    Science.gov (United States)

    Gonzalez, Andrea; Catherine, Nicole; Boyle, Michael; Jack, Susan M; Atkinson, Leslie; Kobor, Michael; Sheehan, Debbie; Tonmyr, Lil; Waddell, Charlotte; MacMillan, Harriet L

    2018-01-26

    Adverse early experiences are associated with long-lasting disruptions in physiology, development and health. These experiences may be 'biologically embedded' into molecular and genomic systems that determine later expressions of vulnerability. Most studies to date have not examined whether preventive interventions can potentially reverse biological embedding. The Nurse-Family Partnership (NFP) is an evidence-based intervention with demonstrated efficacy in improving prenatal health, parenting and child functioning. The Healthy Foundations Study is an innovative birth cohort which will evaluate the impact of the NFP on biological outcomes of mothers and their infants. Starting in 2013, up to 400 pregnant mothers and their newborns were recruited from the British Columbia Healthy Connections Project-a randomised controlled trial of the NFP, and will be followed to child aged 2 years. Women were recruited prior to 28 weeks' gestation and then individually randomised to receive existing services (comparison group) or NFP plus existing services (intervention group). Hair samples are collected from mothers at baseline and 2 months post partum to measure physiological stress. Saliva samples are collected from infants during all visits for analyses of stress and immune function. Buccal swabs are collected from infants at 2 and 24 months to assess DNA methylation. Biological samples will be related to child outcome measures at age 2 years. The study received ethical approval from seven research ethics boards. Findings from this study will be shared broadly with the research community through peer-reviewed publications, and conference presentations, as well as seminars with our policy partners and relevant healthcare providers. The outcomes of this study will provide all stakeholders with important information regarding how early adversity may lead to health and behavioural disparities and how these may be altered through early interventions. NCT01672060; Pre-results.

  20. Precise single-qubit control of the reflection phase of a photon mediated by a strongly-coupled ancilla–cavity system

    Science.gov (United States)

    Motzoi, F.; Mølmer, K.

    2018-05-01

    We propose to use the interaction between a single qubit atom and a surrounding ensemble of three level atoms to control the phase of light reflected by an optical cavity. Our scheme employs an ensemble dark resonance that is perturbed by the qubit atom to yield a single-atom single photon gate. We show here that off-resonant excitation towards Rydberg states with strong dipolar interactions offers experimentally-viable regimes of operations with low errors (in the 10‑3 range) as required for fault-tolerant optical-photon, gate-based quantum computation. We also propose and analyze an implementation within microwave circuit-QED, where a strongly-coupled ancilla superconducting qubit can be used in the place of the atomic ensemble to provide high-fidelity coupling to microwave photons.

  1. Understanding biological control of greenhouse whitefly with the parasitoid Encarsia formosa : from individual behaviour to population dynamics

    NARCIS (Netherlands)

    Roermund, van H.J.W.

    1995-01-01

    The greenhouse whitefly, Trialeurodes vaporariorum (Westwood) (Homoptera, Aleyrodidae), is a very common, highly polyphagous pest insect all over the world. Biological control of whiteflies with the parasitoid Encarsia formosa Gahan (Hymenoptera, Aphelinidae) was already applied in the 1920s in

  2. Biological Control of White Rot in Garlic Using Burkholderia pyrrocinia CAB08106-4

    Directory of Open Access Journals (Sweden)

    Kwang Seop Han

    2013-03-01

    Full Text Available White rot caused by Sclerotium cepivorum was reported to be severe soil-born disease on garlic. Disease progress of white rot of garlic (Allium sativum L. was investigated during the growing season of 2009 to 2011 at Taean and Seosan areas. The white rot disease on bulb began to occur from late April and peaked in late May. The antifungal bacteria, Burkholderia pyrrocinia CAB08106-4 was tested in field bioassay for suppression of white rot disease. As a result of the nucleotide sequence of the gene 16S rRNA, CAB008106-4 strain used in this study has been identified as B. pyrrocinia. B. pyrrocinia CAB080106-4 isolate suppressed the white rot with 69.6% control efficacy in field test. These results suggested that B. pyrrocinia CAB08106-4 isolate could be an effective biological control agent against white rot of garlic.

  3. Biological Control Of The Egyptian Brown Rot In Potato (Solanum Tuberosum L.)

    International Nuclear Information System (INIS)

    Salem, E.A.; Askora, A. M.

    2012-01-01

    Pseudomonas fluorescence, P. aeruginosa, Bacillus subtillus and streptomyces spp. Were used in control of Ralstonia solanacearum, the casual agent of brown rot in potato. In vitro, antagonistic activities showed that streptomyces spp. was the most antagonistic followed by P. fluorescence, Bacillus subtilus and P. aeruginosa respectively. Also, in vivo, biological control of R. solanacearum showed that Streptomyces spp. was found to reduce the percentage of brown rot infection to 5% followed by P. fluorescence, Bacillus subtilus and P. aeruginosa reducing the percentage of infection to 15 , 25 and 40%, respectively. Also, the disease severity when using Streptomyces spp. and P. fluorescence was reduced from 5 to 1 and reduced from 5 to 2 when using Bacillus subtilus and P. aeruginosa.

  4. Biological and Cultural Control of Olive Fruit Fly in California---Utilization of Parasitoids from USDA-APHIS-PPQ, Guatemala and Cultural Control Methods

    Science.gov (United States)

    The parasitoid Psytallia humilis = P. cf. concolor (Szépligeti) was reared on sterile Mediterranean fruit fly, Ceratitis capitata (Wiedemann), larvae at the USDA, APHIS, PPQ, Moscamed biological control laboratory in San Miguel Petapa, Guatemala and shipped to the USDA, ARS, Parlier, for biological ...

  5. COMPLEMENTARY SEX DETERMINATION IN HYMENOPTERAN PARASITOIDS AND ITS IMPLICATIONS FOR BIOLOGICAL CONTROL

    Institute of Scientific and Technical Information of China (English)

    WUZhishan; KeithR.Hopper; PaulJ.Ode; RogerW.Fuester; CHENJia-hua; GeorgeE.Heimpel

    2003-01-01

    In haplodiploid Hymenoptera, unfertilized eggs produce haploid males while fertilized eggs lead to diploid females under most circumstances. Diploid males can also be produced from fertilization under a system of sex determination known as complementary sex determination (CSD). Under single-locus CSD, sex is determined by multiple alleles at a single sex locus. Individuals heterozygous at the sex locus are female while hemizygous and homozygous individuals develop as haploid and diploid males, respectively. In multiple-locus CSD, two or more loci, each with two or more alleles, determine sex. Diploid individuals are female if one or more sex loci are het-erozygous, while a diploid is male only if homozygous at all sex loci. Diploid males are known to occur in 43 hym-enopteran species and single-locus CSD has been demonstrated in 22 of these species. Diploid males are either developmentally inviable or sterile, so their production constitutes a genetic load. Because diploid male production is more likely under inbreeding, CSD is a form of inbreeding depression. It is crucial to preserve the diversity of sex alleles and reduce the loss of genetic variation in biological control. In the parasitoid species with single-locus CSD, certain precautionary procedures can prevent negative effects of single-locus CSD on biological control.

  6. Biological Control to Protect Watermelon Blossoms and Seed from Infection by Acidovorax avenae subsp. citrulli.

    Science.gov (United States)

    Fessehaie, A; Walcott, R R

    2005-04-01

    ABSTRACT The efficacy of biological control seed treatments with Pseudomonas fluorescens (A506), Acidovorax avenae subsp. avenae (AAA 99-2), and an unidentified gram-positive bacterium recovered from watermelon seed (WS-1) was evaluated for the management of bacterial fruit blotch (BFB) of watermelon. In growth chamber and greenhouse experiments, seed treated with AAA 99-2 displayed superior disease suppression, reducing BFB transmission by 96.5%. AAA 99-2, P. fluorescens A506, and Kocide also suppressed the epiphytic growth of A. avenae subsp. citrulli when applied to attached watermelon blossoms 5 h prior to inoculation. Watermelon blossom protection reduced seed infestation by A. avenae subsp. citrulli. From blossoms treated with 0.1 M phosphate buffered saline (PBS), 63% of the resulting seed lots were infested with A. avenae subsp. citrulli. In contrast, for blossoms protected with WS-1, Kocide, P. fluorescens A506, and AAA 99-2, the proportion of infested seed lots were 48.3, 21.1, 24.1, and 13.8%, respectively. The effect of blossom treatments on seed lot infestation was statistically significant (P = 0.001) but WS-1 was not significantly different from PBS. These findings suggest that blossom protection with biological control agents could be a feasible option for managing BFB.

  7. Granular formulation of Fusarium oxysporum for biological control of faba bean and tomato Orobanche.

    Science.gov (United States)

    Nemat Alla, Mamdouh M; Shabana, Yasser M; Serag, Mamdouh M; Hassan, Nemat M; El-Hawary, Mohamed M

    2008-12-01

    Orobanche spp. represent a serious threat to a wide range of crops. They are difficult targets for herbicides, and biological control could provide a possible solution. This work therefore aimed to formulate mycoherbicides of Fusarium with adequate shelf life and virulence against Orobanche but safe to faba bean and tomato. Only two isolates of Fusarium oxysporum Schlecht. (Foxy I and Foxy II) obtained from diseased Orobanche shoots were found to be pathogenic to Orobanche crenata Forsk. and Orobanche ramosa L. Conidial suspension of both isolates significantly decreased germination, attachments and tubercles of Orobanche. Microconidia and chlamydospores of both isolates were formulated as mycoherbicides encapsulated in a wheat flour-kaolin matrix (four different formulations). All formulations greatly diminished Orobanche emerged shoots, total shoot number, shoot height, attachment of emerged shoots, the germinated seeds that succeeded in emerging above the soil surface and dry weight. Meanwhile, disease incidence and disease severity of emerged shoots were enhanced. The shelf life was adequate, particularly for coarse, freshly prepared, low-temperature-stored, microconidia-rich formulations. The induced growth reduction of Orobanche-infected host plants seemed to be nullified by formulations, particularly at the highest dose. These formulations seemed to destroy Orobanche but appeared harmless to host plants. Hence, they could be efficiently used as mycoherbicides for biological control of Orobanche in faba bean and tomato.

  8. Biological control strategies of mycotoxigenic fungi and associated mycotoxins in Mediterranean basin crops

    Directory of Open Access Journals (Sweden)

    Dimitrios I. TSITSIGIANNIS

    2012-05-01

    Full Text Available Fungi that belong to the genera Aspergillus, Fusarium, and Penicillium pose serious phytopathological and mycotoxicological risks at pre-harvest and post-harvest stages, as well as in processed food products because they can produce several mycotoxins. Mycotoxins pose a serious problem for animal and human health and have a significant economic impact worldwide. The Mediterranean basin is a large geographical region with a temperate climate supporting the cultivation of a wealth of field and greenhouse crops with a high risk of mycotoxin contamination. The most important mycotoxins that occur in the Mediterranean basin are aflatoxins (B1, B2, G1 and G2 in dried fruits and nuts, ochratoxin A in grapes and raisins as well as trichothecenes and fumonisins in cereals. A variety of chemical, biological and physical strategies have been developed to control the mycotoxigenic pathogens; to minimize mycotoxin production at pre- or post-harvest level; to contribute to decontamination and/or detoxification of mycotoxins from contaminated foods and feeds; or to inhibit mycotoxin absorption in the gastrointestinal tract. Biological control using microbial antagonists either alone or as part of an integrated control strategy to reduce pesticide inputs, has emerged as a promising approach for control of mycotoxins in crops, both pre- and post-harvest. Several organisms including atoxigenic Aspergilli, yeasts, bacteria and fungi have been tested for their ability to reduce both fungal infection and mycotoxin contamination. For instance, atoxigenic fungal strains are being used widely to prevent pre-harvest aflatoxin contamination of crops such as peanuts, pistachios, maize, and cottonseed in several parts of the world including the Mediterranean area. Recent advancements in the use of biocontrol strategies have led to registration of commercial products with increased practical applications for the benefit of growers in several countries.

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

    Directory of Open Access Journals (Sweden)

    M Abdigoudarzi

    2009-12-01

    Full Text Available 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 these strains were evaluated on adult stages of two Iranian Ixodidae members (H. anatolicum anatolicum Koch 1844, and H. marginatum Koch 1844 by dipping method.Methods: Two Iranian strains of Beauveria bassiana (Beauveria bassiana 5197 and Beauveria bassiana Evin were selected and were grown successfully on specific media. The pathogenic effects of these strains were evaluated on adult stages of Iranian Ixodidae members such as, Hyalomma anatolicum anatolicum and H. marginatum by dipping method (these ticks were grown up at laboratory conditions during 2002 up to 2003 and still it is continued .Results: There was no effect of strain 5197 on mortality or fecundity rates for ticks. There was acute phase sign of paralysis in test group after dipping ticks in suspension made from Evin strain of B. bassiana. In addition, the test groups were totally died after four months, but the control groups survived for six months.Conclusion: High concentration of fungal spores is needed for inducing fungal infection. Additional study using different strains and fungi on Iranian ticks is proposed. 

  10. 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.

  11. Biological Control beneath the Feet: A Review of Crop Protection against Insect Root Herbivores.

    Science.gov (United States)

    Kergunteuil, Alan; Bakhtiari, Moe; Formenti, Ludovico; Xiao, Zhenggao; Defossez, Emmanuel; Rasmann, Sergio

    2016-11-29

    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.

  12. Controlled fabrication of the strong emission YVO{sub 4}:Eu{sup 3+} nanoparticles and nanowires by microwave assisted chemical synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Huong, Tran Thu, E-mail: tthuongims@gmail.com [Institute of Materials Science, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet Road, Cau Giay District, Hanoi (Viet Nam); Vinh, Le Thi [Institute of Materials Science, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet Road, Cau Giay District, Hanoi (Viet Nam); Department of Chemistry, Hanoi University of Mining and Geology (Viet Nam); Phuong, Ha Thi [Institute of Materials Science, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet Road, Cau Giay District, Hanoi (Viet Nam); Department of Chemistry, Hanoi University of Medicine (Viet Nam); Khuyen, Hoang Thi [Institute of Materials Science, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet Road, Cau Giay District, Hanoi (Viet Nam); Anh, Tran Kim [Institute of Materials Science, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet Road, Cau Giay District, Hanoi (Viet Nam); Duy Tan University, 14/25 Quang Trung, Da Nang (Viet Nam); Tu, Vu Duc [Institute of Materials Science, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet Road, Cau Giay District, Hanoi (Viet Nam); Physics, National Chung Cheng University, 168 University Road, Min-Hsiung, Chia-Yi 62102, Taiwan (China); Minh, Le Quoc [Institute of Materials Science, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet Road, Cau Giay District, Hanoi (Viet Nam); Duy Tan University, 14/25 Quang Trung, Da Nang (Viet Nam)

    2016-05-15

    In this report, we are presenting the controlled fabrication results of the strong emission YVO{sub 4}: Eu{sup 3+} nanoparticles and nanowires by microwave which is assisted chemical synthesis. The effects of incorporated synthesis conditions such as microwave irradiated powers, pH values and concentration of chemical composition on properties of nanomaterials are also investigated to obtain the controllable size and homogenous morphology. Morphological and optical properties of YVO{sub 4}: Eu{sup 3+} prepared products which have been characterized by X-ray diffraction (XRD), field emission micrcroscopy (FESEM) and photoluminescence spectroscopy. As based from result of synthesized samples, we found that the changing of pH values, microwave irradiated powers and chemical composition rise to change reform the size and shape of materials from nanoparticles (diameter about 20 nm) to wires shape (with about 500÷800 nm length and 10÷20 nm width). The photoluminescence (PL) spectroscopy measurements of YVO{sub 4}: Eu{sup 3+} nanostructure materials under UV excitation showed that: the strong luminescence in red region with narrow lines corresponding to the intra-4f transitions of {sup 5}D{sub 0}–{sup 7}F{sub j} (j=1, 2, 3, and 4) of Eu{sup 3+} ions with the highest luminescence intensity of {sup 5}D{sub 0}→{sup 7}F{sub 2} transition. - Highlights: • The strong emission YVO{sub 4}:Eu{sup 3+} nanostructure materials were successfully synthesized by microwave assisted chemical synthesis. • The size, morphology and luminescence of the YVO{sub 4}:Eu{sup 3+} nanostructure materials can be controlled by the solution pH, microwave irradiated powers and chemical composition. • These YVO{sub 4}:Eu{sup 3+} nanostructure materials above can potentially applied in various fields of application, especially in luminescent labeling and visualization in biomedical application.

  13. Invasive Australian Acacia seed banks: Size and relationship with stem diameter in the presence of gall-forming biological control agents.

    Directory of Open Access Journals (Sweden)

    Matthys Strydom

    Full Text Available Australian Acacia are invasive in many parts of the world. Despite significant mechanical and biological efforts to control their invasion and spread, soil-stored seed banks prevent their effective and sustained removal. In response South Africa has had a strong focus on employing seed reducing biological control agents to deal with Australian Acacia invasion, a programme that is considered as being successful. To provide a predictive understanding for their management, seed banks of four invasive Australian acacia species (Acacia longifolia, A. mearnsii, A. pycnantha and A. saligna were studied in the Western Cape of South Africa. Across six to seven sites for each species, seed bank sizes were estimated from dense, monospecific stands by collecting 30 litter and soil samples. Average estimated seed bank size was large (1017 to 17261 seed m-2 as was annual input into the seed bank, suggesting that these seed banks are not residual but are replenished in size annually. A clear relationship between seed bank size and stem diameter was established indicating that mechanical clearing should be conducted shortly after fire-stimulated recruitment events or within old populations when seed banks are small. In dense, monospecific stands seed-feeding biological control agents are not effective in reducing seed bank size.

  14. Individual genetic variations related to satiety and appetite control increase risk of obesity in preschool-age children in the STRONG kids program.

    Science.gov (United States)

    Wang, Yingying; Wang, Anthony; Donovan, Sharon M; Teran-Garcia, Margarita

    2013-01-01

    The burden of the childhood obesity epidemic is well recognized; nevertheless, the genetic markers and gene-environment interactions associated with the development of common obesity are still unknown. In this study, candidate genes associated to satiety and appetite control pathways with obesity-related traits were tested in Caucasian preschoolers from the STRONG Kids project. Eight genetic variants in genes related to obesity (BDNF, LEPR, FTO, PCSK1, POMC, TUB, LEP, and MC4R) were genotyped in 128 children from the STRONG Kids project (mean age 39.7 months). Data were analyzed for individual associations and to test for genetic predisposition scores (GPSs) with body mass index (BMI) and anthropometric traits (Z-scores, e.g. height-for-age Z-score, HAZ). Covariates included age, sex, and breastfeeding (BF) duration. Obesity and overweight prevalence was 6.3 and 19.5%, respectively, according to age- and sex-specific BMI percentiles. Individual genetic associations of MC4R and LEPR markers with HAZ were strengthened when BF duration was included as a covariate. Our GPSs show that, as the number of risk alleles increased, the risk of higher BMI and HAZ also increased. Overall, the GPSs assembled were able to explain 2-3% of the variability in BMI and HAZ phenotypes. Genetic associations with common obesity-related phenotypes were found in the STRONG Kids project. GPSs assembled for specific candidate genes were associated with BMI and HAZ phenotypes. © 2013 S. Karger AG, Basel.

  15. Merging metagenomics and geochemistry reveals environmental controls on biological diversity and evolution.

    Science.gov (United States)

    Alsop, Eric B; Boyd, Eric S; Raymond, Jason

    2014-05-28

    The metabolic strategies employed by microbes inhabiting natural systems are, in large part, dictated by the physical and geochemical properties of the environment. This study sheds light onto the complex relationship between biology and environmental geochemistry using forty-three metagenomes collected from geochemically diverse and globally distributed natural systems. It is widely hypothesized that many uncommonly measured geochemical parameters affect community dynamics and this study leverages the development and application of multidimensional biogeochemical metrics to study correlations between geochemistry and microbial ecology. Analysis techniques such as a Markov cluster-based measure of the evolutionary distance between whole communities and a principal component analysis (PCA) of the geochemical gradients between environments allows for the determination of correlations between microbial community dynamics and environmental geochemistry and provides insight into which geochemical parameters most strongly influence microbial biodiversity. By progressively building from samples taken along well defined geochemical gradients to samples widely dispersed in geochemical space this study reveals strong links between the extent of taxonomic and functional diversification of resident communities and environmental geochemistry and reveals temperature and pH as the primary factors that have shaped the evolution of these communities. Moreover, the inclusion of extensive geochemical data into analyses reveals new links between geochemical parameters (e.g. oxygen and trace element availability) and the distribution and taxonomic diversification of communities at the functional level. Further, an overall geochemical gradient (from multivariate analyses) between natural systems provides one of the most complete predictions of microbial taxonomic and functional composition. Clustering based on the frequency in which orthologous proteins occur among metagenomes

  16. 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

  17. Biological control of Anopheles darlingi, Aedes aegypti and Culex quinquefasciatus larvae using shrimps

    Directory of Open Access Journals (Sweden)

    Willian Marinho Dourado Coelho

    2017-08-01

    Full Text Available Mosquitoes can act as vectors of important diseases such as malaria, dengue, Zika virus, yellow fever, Chikungunya and Mayaro fever, in addition to filariasis. The use of insecticides, larvicides, bed nets and repellents, besides the use of drugs as chemoprevention and the treatment of the sick are currently the pillars of the control of these vectors. We studied the biological control against of Anopheles darlingi, Aedes aegypti and Culex quinquefasciatus larvae using shrimps of the species M. pantanalense, M. amazonicum, M. brasiliense and M. jelskii. Larvae of mosquitoes were collected from the breeding environment and placed in a 500 and 1000 l tank containing 60 shrimps/m2. The predatory activity was evaluated for 30 days and, in all groups it was observed that 100% of the larvae were consumed in few minutes. In the environment, these same species of crustaceans were released in water bodies with the presence of larvae of these insects. In just 72 h there was a marked reduction of the larvae in the release sites of shrimps. Similarly, there was a reduction in the number of adult mosquitoes caught near the breeding sites, allowing to infer that, in places where the crustaceans were released, the predatory activity on the larvae of mosquitoes was sufficient to reduce the number of adult mosquitoes p ≤ 0,05. This is the first description of the predatory activity of M. pantanalense, M. amazonicum, M. brasiliense and M. jelskii on An. darlingi, A. aegypti and C. quinquefasciatus larvae, constituting an important tool of biological control of these parasites-vectors.

  18. Area-wide integration of lepidopteran F1 sterility and augmentative biological control

    International Nuclear Information System (INIS)

    Carpenter, James E.

    2000-01-01

    Area-wide pest management (APM) and integrated pest management (IPM) originated from two different efforts to combine two or more control techniques into programmes in which each method could synergise the effectiveness of others and thus create a level of pest control that was greater than that of a single technique (Perkins 1982). Since then, the concept of APM has evolved to include many aspects of IPM and often is now referred to as area-wide IPM. Still, the element of total population management is central to this approach of insect pest management. In support of APM, Knipling (1998) stated that of the insect pests that were of major concern to agriculture before the newer classes of insecticides were available, most are still pests today, the major exceptions being the screw-worm fly and the boll weevil in the southeastern US cotton growing region. Knipling also noted that both of these pest species were subjected to area-wide suppression programmes. In response to the USDA IPM Initiative (USDA 1993, 1994) which seeks to achieve the national goal of having 75% of the crop acres under IPM by the year 2000, the Agricultural Research Service developed an Area-wide IPM Programme. This programme combines environmentally-sound pest control techniques with the advantages of APM and develops partnerships with other federal, state, local and private sector entities. Technologies such as the integration of lepidopteran F 1 sterility and augmentative biological control may be considered for future programmes

  19. Maneuvering control and configuration adaptation of a biologically inspired morphing aircraft

    Science.gov (United States)

    Abdulrahim, Mujahid

    Natural flight as a source of inspiration for aircraft design was prominent with early aircraft but became marginalized as aircraft became larger and faster. With recent interest in small unmanned air vehicles, biological inspiration is a possible technology to enhance mission performance of aircraft that are dimensionally similar to gliding birds. Serial wing joints, loosely modeling the avian skeletal structure, are used in the current study to allow significant reconfiguration of the wing shape. The wings are reconfigured to optimize aerodynamic performance and maneuvering metrics related to specific mission tasks. Wing shapes for each mission are determined and related to the seagulls, falcons, albatrosses, and non-migratory African swallows on which the aircraft are based. Variable wing geometry changes the vehicle dynamics, affording versatility in flight behavior but also requiring appropriate compensation to maintain stability and controllability. Time-varying compensation is in the form of a baseline controller which adapts to both the variable vehicle dynamics and to the changing mission requirements. Wing shape is adapted in flight to minimize a cost function which represents energy, temporal, and spatial efficiency. An optimal control architecture unifies the control and adaptation tasks.

  20. Cognitive control dysfunction and abnormal frontal cortex activation in stimulant drug users and their biological siblings.

    Science.gov (United States)

    Smith, D G; Jones, P S; Bullmore, E T; Robbins, T W; Ersche, K D

    2013-05-14

    Cognitive and neural abnormalities are known to accompany chronic drug abuse, with impairments in cognition and changes in cortical structure seen in stimulant-dependent individuals. However, premorbid differences have also been observed in the brains and behavior of individuals at risk for substance abuse, before they develop dependence. Endophenotype research has emerged as a useful method for assessing preclinical traits that may be risk factors for pathology by studying patient populations and their undiagnosed first-degree relatives. This study used the color-word Stroop task to assess executive functioning in stimulant-dependent individuals, their unaffected biological siblings and unrelated healthy control volunteers using a functional magnetic resonance imaging paradigm. Both the stimulant-dependent and sibling participants demonstrated impairments in cognitive control and processing speed on the task, registering significantly longer response latencies. However, the two groups generated very different neural responses, with the sibling participants exhibiting a significant decrease in activation in the inferior frontal gyrus compared with both stimulant-dependent individuals and control participants. Both target groups also demonstrated a decrease in hemispheric laterality throughout the task, exhibiting a disproportionate increase in right hemispheric activation, which was associated with their behavioral inefficiencies. These findings not only suggest a possible risk factor for stimulant abuse of poor inhibitory control and cortical inefficiency but they also demonstrate possible adaptations in the brains of stimulant users.

  1. Biology, ecology and control of the Penthaleus species complex (Acari: Penthaleidae).

    Science.gov (United States)

    Umina, Paul A; Hoffmann, Ary A; Weeks, Andrew R

    2004-01-01

    Blue oat mites, Penthaleus spp. (Acari: Penthaleidae), are major agricultural pests in southern Australia and other parts of the world, attacking various pasture, vegetable and crop plants. Management of these mites has been complicated by the recent discovery of three cryptic pest species of Penthaleus, whereas prior research had assumed a single species. The taxonomy, population genetics, ecology, biology and control of the Penthaleus spp. complex are reviewed. Adult Penthaleus have a dark blue-black body approximately 1 mm in length, and eight red-orange legs. Within Australia, they are winter pests completing two or three generations a season, depending on conditions. The summer is passed as diapausing eggs, when long-distance dispersal is thought to occur. The Penthaleus spp. reproduce by thelytokous parthenogenesis, with populations comprising clones that differ ecologically. The three pest Penthaleus spp. differ markedly in their distributions, plant hosts, timing of diapause egg production and response to pesticides, highlighting the need to develop control strategies that consider each species separately. Chemicals are the main weapons used in current control programs, however research continues into alternative more sustainable management options. Host plant resistance, crop rotations, conservation of natural enemies, and improved timing of pesticide application would improve the management of these pests. The most cost-effective and environmentally acceptable means of control will result from the integration of these practices combined with the development of a simple field-based kit to distinguish the different mite species.

  2. Molecular biological approaches to the study of vectors in relation to malaria control

    Directory of Open Access Journals (Sweden)

    J. M. Crampton

    1992-01-01

    Full Text Available To a large extent, control of malaria vectors relies on the elimination of breeding sites and the application of chemical agents. There are increasing problems associated with the use of synthetic insecticides for vector control, including the evolution of resistance, the high cost of developing and registering new insecticides and an awareness of pollution from insecticide residues. These factors have stimulated interest in the application of molecular biology to the study of mosquito vectors of malaria; focussing primarily on two aspects. First, the improvement of existing control measures through the development of simplified DNA probe systems suitable for identification of vectors of malaria. The development of synthetic, non-radioactive DNA probes suitable for identification of species in the Anopheles gambiae complex is described with the aim of defining a simplified methodology wich is suitable for entomologist in the field. The second aspect to be considered is the development of completely novel strategies through the development of completely novel strategies through the genetic manipulation of insect vectors of malaria in order to alter their ability to transmit the disease. The major requirements for producing transgenic mosquitoes are outlined together with the progress wich has been made to date and discussed in relation to the prospects which this type of approach has for the future control of malaria.

  3. 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

    2011-01-01

    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. PMID:21666030

  4. Comparative taphonomy, taphofacies, and bonebeds of the Mio-Pliocene Purisima Formation, central California: strong physical control on marine vertebrate preservation in shallow marine settings.

    Directory of Open Access Journals (Sweden)

    Robert W Boessenecker

    Full Text Available Taphonomic study of marine vertebrate remains has traditionally focused on single skeletons, lagerstätten, or bonebed genesis with few attempts to document environmental gradients in preservation. As such, establishment of a concrete taphonomic model for shallow marine vertebrate assemblages is lacking. The Neogene Purisima Formation of Northern California, a richly fossiliferous unit recording nearshore to offshore depositional settings, offers a unique opportunity to examine preservational trends across these settings.Lithofacies analysis was conducted to place vertebrate fossils within a hydrodynamic and depositional environmental context. Taphonomic data including abrasion, fragmentation, phosphatization, articulation, polish, and biogenic bone modification were recorded for over 1000 vertebrate fossils of sharks, bony fish, birds, pinnipeds, odontocetes, mysticetes, sirenians, and land mammals. These data were used to compare both preservation of multiple taxa within a single lithofacies and preservation of individual taxa across lithofacies to document environmental gradients in preservation. Differential preservation between taxa indicates strong preservational bias within the Purisima Formation. Varying levels of abrasion, fragmentation, phosphatization, and articulation are strongly correlative with physical processes of sediment transport and sedimentation rate. Preservational characteristics were used to delineate four taphofacies corresponding to inner, middle, and outer shelf settings, and bonebeds. Application of sequence stratigraphic methods shows that bonebeds mark major stratigraphic discontinuities, while packages of rock between discontinuities consistently exhibit onshore-offshore changes in taphofacies.Changes in vertebrate preservation and bonebed character between lithofacies closely correspond to onshore-offshore changes in depositional setting, indicating that the dominant control of preservation is exerted by physical

  5. Comparative taphonomy, taphofacies, and bonebeds of the Mio-Pliocene Purisima Formation, central California: strong physical control on marine vertebrate preservation in shallow marine settings.

    Science.gov (United States)

    Boessenecker, Robert W; Perry, Frank A; Schmitt, James G

    2014-01-01

    Taphonomic study of marine vertebrate remains has traditionally focused on single skeletons, lagerstätten, or bonebed genesis with few attempts to document environmental gradients in preservation. As such, establishment of a concrete taphonomic model for shallow marine vertebrate assemblages is lacking. The Neogene Purisima Formation of Northern California, a richly fossiliferous unit recording nearshore to offshore depositional settings, offers a unique opportunity to examine preservational trends across these settings. Lithofacies analysis was conducted to place vertebrate fossils within a hydrodynamic and depositional environmental context. Taphonomic data including abrasion, fragmentation, phosphatization, articulation, polish, and biogenic bone modification were recorded for over 1000 vertebrate fossils of sharks, bony fish, birds, pinnipeds, odontocetes, mysticetes, sirenians, and land mammals. These data were used to compare both preservation of multiple taxa within a single lithofacies and preservation of individual taxa across lithofacies to document environmental gradients in preservation. Differential preservation between taxa indicates strong preservational bias within the Purisima Formation. Varying levels of abrasion, fragmentation, phosphatization, and articulation are strongly correlative with physical processes of sediment transport and sedimentation rate. Preservational characteristics were used to delineate four taphofacies corresponding to inner, middle, and outer shelf settings, and bonebeds. Application of sequence stratigraphic methods shows that bonebeds mark major stratigraphic discontinuities, while packages of rock between discontinuities consistently exhibit onshore-offshore changes in taphofacies. Changes in vertebrate preservation and bonebed character between lithofacies closely correspond to onshore-offshore changes in depositional setting, indicating that the dominant control of preservation is exerted by physical processes. The

  6. Risk assessment, eradication, and biological control: global efforts to limit Australian acacia invasions

    Science.gov (United States)

    Wilson, John R.U.; Gairifo, Carla; Gibson, Michelle R.; Arianoutsou, Margarita; Bakar, Baki B.; Baret, Stephane; Celesti-Grapow, Laura; DiTomaso, Joseph M.; Dufour-Dror, Jean-Marc; Kueffer, Christoph; Kull, Christian A.; Hoffman, John H.; Impson, Fiona A.C.; Loope, Lloyd L.; Marchante, Elizabete; Harchante, Helia; Moore, Joslin L.; Murphy, Daniel J.; Tassin, Jacques; Witt, Arne; Zenni, Rafael D.; Richardson, David M.

    2011-01-01

    Aim Many Australian Acacia species have been planted around the world, some are highly valued, some are invasive, and some are both highly valued and invasive. We review global efforts to minimize the risk and limit the impact of invasions in this widely used plant group. Location Global. Methods Using information from literature sources, knowledge and experience of the authors, and the responses from a questionnaire sent to experts around the world, we reviewed: (1) a generalized life cycle of Australian acacias and how to control each life stage, (2) different management approaches and (3) what is required to help limit or prevent invasions. Results Relatively few Australian acacias have been introduced in large numbers, but all species with a long and extensive history of planting have become invasive somewhere. Australian acacias, as a group, have a high risk of becoming invasive and causing significant impacts as determined by existing assessment schemes. Moreover, in most situations, long-lived seed banks mean it is very difficult to control established infestations. Control has focused almost exclusively on widespread invaders, and eradication has rarely been attempted. Classical biological control is being used in South Africa with increasing success. Main conclusions A greater emphasis on pro-active rather than reactive management is required given the difficulties managing established invasions of Australian acacias. Adverse effects of proposed new introductions can be minimized by conducting detailed risk assessments in advance, planning for on-going monitoring and management, and ensuring resources are in place for long-term mitigation. Benign alternatives (e.g. sterile hybrids) could be developed to replace existing utilized taxa. Eradication should be set as a management goal more often to reduce the invasion debt. Introducing classical biological control agents that have a successful track-record in South Africa to other regions and identifying new

  7. Management of vascular wilt of lentil through host plant resistance, biological control agents and chemicals

    International Nuclear Information System (INIS)

    Rafique, K.; Rauf, C.A.; Naz, F.

    2016-01-01

    The management of devastating lentil (Lens culinaris Medik.) wilt disease was investigated through evaluation of host plant resistance, biological control agents and seed treatment with different fungicides against a known most aggressive isolate i.e. FWL12 (KP297995) of Fusarium oxysporum f. sp. lentis. The In vitro screening of germplasm (23 advanced lines and cultivars) for host resistance by root dip method revealed five cultivars viz. Markaz-09, Masoor-86, Masoor-2006, Punjab Masoor-00518 and Punjab Masoor-09 resistant with 20 to 46.67% incidence, 4.44 to 12.95% severity index and 9.60 to 24.94% yield reduction compared with highly susceptible (100% incidence) local lentil line (NARC-08-1). The later line was treated with Trichoderma species as antagonists in pot experiment by drenching. The bio-control treatment revealed maximum positive effect of T. harzianum (26.7% incidence, 8.9% severity index and 16.27% yield reduction), followed by T. viride (66.7% incidence, 17.8% severity index and 31.13% yield reduction). On inoculated untreated control, the fungus produced the characteristic wilt symptoms and significantly caused increased severity index, incidence and decreased 100% yield. In vitro evaluation of four fungicides at five concentrations (10, 20, 30, 50 and 100 ppm) revealed maximum inhibition of the test fungus with benomyl (85.9%), followed by thiophanate methyl (81.2%). Determination of the efficacy of two best fungicides viz. benomyl and thiophanate methyl in reducing wilt infection through In vivo seed treatment of NARC-08-1 in previously inoculated potting mixture revealed 100% seed germination and suppressed wilt disease, the most effective being benomyl with 6.7% incidence, 1.5% wilt severity and 17.16% yield reduction compared to the control. The study concluded that the genetic diversity already present in lentil cultivars is an important source, which could be exploited for breeding wilt resistant lentil genotypes. Moreover, being seed and

  8. Selection of halophilic bacteria for biological control of tomato gray mould caused by Botrytis cinerea

    Directory of Open Access Journals (Sweden)

    Imane BERRADA

    2013-01-01

    Full Text Available In Morocco, tomato gray mould caused by Botrytis cinerea Pers: Fr. is a serious threat for postharvest storage of tomatoes. Fifteen halophilic bacteria were evaluated for their antagonistic activity against B. cinerea: 11 Gram positive strains assigned to the genera Bacillus (9, Jeotgalibacillus (1 and Planococcus (1 and four Gram negative strains assigned to the genera Salinivibrio (1, Vibrio (2 and Photobacterium (1. In in vitro screening, 12 antifungal isolates secreted diffusible compounds, hydrolytic enzymes or volatile compounds. In vivo screening of the isolates, Bacillus safensis CCMM B582 and Bacillus oceanisediminis CCMM B584 showed permanent antagonistic activity on tomato fruits, with 100% inhibition of B. cinerea after 7 days. These two strains may offer potential for biological control of tomato gray mould.

  9. 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

    Plant diseases are one of the seriously limiting factors of agriculture efficiency around the world. Diseases caused by fungi are the major threat to plants. Crop protection in modern agriculture heavily depends on chemical fungicides. Disadvantages of chemical pesticides soon became apparent as damage to the environment and a hazard to human health. In this regard use of biopesticides becomes an attractive alternative method of plant protection. For biological control of fungal plant diseases, separate bacterial or fungal strains as well as their communities can be used. Biopreparations must consist of microbes that are typical for local climate and soil conditions and therefore are able to survive in environments for a long time. Another option of plant pests' biological control is implementation of suppressive composts made of agricultural or other organic wastes. These composts can not only prevent the development of plant diseases, but also improve the soil fertility. The objective of this work was estimation of potential of composts and strains isolated from these composts as means for biological control of fusariosis that is one of the most widespread plant soil born disease. The composts were made up of the commonly produced agricultural wastes produced in Tatarstan Republic (Russia). Fusarium oxysporum f. sp. radicis-lycopersici was used as a model phytopathogen. Ten types of organic waste (Goat manure (GM), Chicken dung (CD), Chicken dung with straw addition (CS), Rabbit dung (RD), Cow manure (CM), Rerotting pork manure (RPM), Fresh pork manure (FPM), Pork manure with sawdust and straw (PMS), the remains of plants and leaves (PL), the vegetable waste (VW) were sampled in the big farms situated in Tatarstan Republic which is one of the main agricultural regions of Russia. The initial wastes were composted for 150 days. Further, the following characteristics of the composts were assessed: pH, electro conductivity, TOC, DOC, Ntot. On petri dishes with meat

  10. Control of the surface radioactive contamination in the field of biological research

    International Nuclear Information System (INIS)

    Calvo, S.; Encina, A. de la; Gaspar, J.; Macias, M. T.; Sanchez, A.; Usera, F.

    2012-01-01

    The manipulation of unsealed sources in biomedical research involves significant risk of radioactive contamination. the aim of this study has been to analyze the radioactive contamination occurring in the field of biomedical research, assessing its magnitude, identifying the equipment that can be contaminated with higher probability and monitoring the evolution of the contaminations production taking into account the radioisotopes and the activities uses, and the radiation protection control applied. The data used for this study correspond to a very lengthy period of time and it have been collected in the radioactive facility, of the Centro Nacional de Biotecnologia (CSIC), a very large biological research centre that can be used perfectly as a reference for this area. The results obtained show a gradual and significant decrease in the incidence of the radioactive contamination. This is due to the optimization of radiation protection standards applied and the implementation or a systematic operational radiation protection program. (Author) 13 refs.

  11. Mind-body therapies and control of inflammatory biology: A descriptive review.

    Science.gov (United States)

    Bower, Julienne E; Irwin, Michael R

    2016-01-01

    The use of mind-body therapies, including Tai Chi, Qigong, yoga, and meditation, has grown steadily in recent years. These approaches have been shown to be effective in reducing symptoms and improving quality of life, and research has begun to examine the impact of these therapies on biological processes, including inflammation. A review of 26 randomized controlled trials was conducted to describe the effects of mind-body therapies (MBTs) on circulating, cellular, and genomic markers of inflammation. This qualitative evaluation showed mixed effects of MBTs on circulating inflammatory markers, including CRP and IL-6, and on measures of stimulated cytokine production. More consistent findings were seen for genomic markers, with trials showing decreased expression of inflammation-related genes and reduced signaling through the proinflammatory transcription factor NF-κB. Potential mechanisms for these effects are discussed, including alterations in neuroendocrine, neural, and psychological and behavioral processes. Copyright © 2015 Elsevier Inc. All rights reserved.

  12. ECOLOGY OF PANTOEA AGGLOMERANS 2066-7 STRAIN: A BIOLOGICAL CONTROL OF BACTERIA ONION DISEASES

    Directory of Open Access Journals (Sweden)

    Soumia Sadik

    2016-06-01

    Full Text Available The growth response of the biocontrol agent Pantoea agglomerans 2066-7 to change in water activity (aw, temperature, and pH was determined in vitro in basic medium. The minimum temperature at which 2066-7 was able to grow was 7°C, and the growth of 2066-7 did not change at varying pH levels (4–10.34. The best growth was obtained at a water activity of 0.98 in all media modified with the four solutes (glucose, glycerol, NaCl and polyethylene glycol. The solute used to reduce water activity had a great influence on bacterial growth, especially at unfavorable conditions (low temperature. This study has defined the range of environmental conditions (aw, pH, and temperature over which the bacteria may be developed for biological control of plant diseases.

  13. A biologically inspired meta-control navigation system for the Psikharpax rat robot

    International Nuclear Information System (INIS)

    Caluwaerts, K; Staffa, M; N’Guyen, S; Grand, C; Dollé, L; Favre-Félix, A; Girard, B; Khamassi, M

    2012-01-01

    A biologically inspired navigation system for the mobile rat-like robot named Psikharpax is presented, allowing for self-localization and autonomous navigation in an initially unknown environment. The ability of parts of the model (e.g. the strategy selection mechanism) to reproduce rat behavioral data in various maze tasks has been validated before in simulations. But the capacity of the model to work on a real robot platform had not been tested. This paper presents our work on the implementation on the Psikharpax robot of two independent navigation strategies (a place-based planning strategy and a cue-guided taxon strategy) and a strategy selection meta-controller. We show how our robot can memorize which was the optimal strategy in each situation, by means of a reinforcement learning algorithm. Moreover, a context detector enables the controller to quickly adapt to changes in the environment—recognized as new contexts—and to restore previously acquired strategy preferences when a previously experienced context is recognized. This produces adaptivity closer to rat behavioral performance and constitutes a computational proposition of the role of the rat prefrontal cortex in strategy shifting. Moreover, such a brain-inspired meta-controller may provide an advancement for learning architectures in robotics. (paper)

  14. Biological control of rice brown spot with native isolates of three Trichoderma species

    Directory of Open Access Journals (Sweden)

    Elham Khalili

    2012-03-01

    Full Text Available Brown spot caused by Bipolaris oryzae is an important rice disease in Southern coast of Caspian Sea, the major rice growing region in Iran. A total of 45 Trichoderma isolates were obtained from rice paddy fields in Golestan and Mazandaran provinces which belonged to Trichoderma harzianum, T. virens and T. atroviride species. Initially, they were screened against B. oryzae by antagonism tests including dual culture, volatile and nonvolatile metabolites and hyperparasitism. Results showed that Trichoderma isolates can significantly inhibit mycelium growth of pathogen in vitro by producing volatile and nonvolatile metabolites Light microscopic observations showed no evidence of mycoparasitic behaviour of the tested isolates of Trichoderma spp. such as coiling around the B. oryzae. According to in vitro experiments, Trichoderma isolates were selected in order to evaluate their efficacy in controlling brown spot in glasshouse using seed treatment and foliar spray methods. Concerning the glasshouse tests, two strains of T. harzianum significantly controlled the disease and one strain of T. atroviride increased the seedling growth. It is the first time that the biological control of rice brown spot and increase of seedling growth with Trichoderma species have been studied in Iran.

  15. [Accidents with biological materials among nurses in a training hospital: case-control study].

    Science.gov (United States)

    Dalarosa, Micheline Gisele; Lautert, Liana

    2009-03-01

    This case-control study aimed at analyzing the association between occupational stress and disagreement between chronotype and the work shift of nurses who suffered accidents with biological materials in a hospital of Porto Alegre, Rio Grande do Sul, Brazil. A number of 99 workers who suffered accidents (cases) and 232 that had not suffered accidents (controls) were interviewed. Data were collected through the Job Stress Scale according to Karasek's model and the Horne-Ostberg scale The occurrence of accident was not statistically associated with high work requirement scores (p = 0.317), with a chronobiological profile discordant with work shift (p = 0.563), or with other labor variables associated to accidents--overtime, having two jobs (p = 1.000). In addition, there was no significant difference (chi2 Pearson; p = 1.00) among the scores of professionals with high work requirements who work in shifts discordant with their chronotype, both in the case group and in the control group as well.

  16. Assessment of Clarias gariepinus as a biological control agent against mosquito larvae.

    Science.gov (United States)

    Chala, Buze; Erko, Berhanu; Animut, Abebe; Degarege, Abraham; Petros, Beyene

    2016-05-31

    The emergence and spread of insecticide resistant mosquitoes renewed interest in investigating the use of larvivorous fish as a biological control agent. The potential of Clarias gariepinus fish in controlling Anopheles arabiensis and culicine larvae was assessed under laboratory and semi-field conditions. Small size (15-20 cm) C. gariepinus fish consumed greater number of mosquito larvae than the large size fish (25-40 cm) in the multivariate regression model (β = 13.36, 95 % CI = 4.57, 22.15). The Anopheles larvae consumed was greater in number than the culicines larvae consumed by the fish (β = 12.10, 95 % CI = 3.31, 20.89). The number of larvae consumed was greater during the night hours than during the light hours (β = 30.06, 95 % CI = 21.27, 38.85). Amount of supplementary fish food did not cause significant differences in the number of mosquito larvae consumed by the fish among different groups. C. gariepinus was observed to feed on mosquito larvae under laboratory and semi-field conditions. C. gariepinus fed on the larvae of An. arabiensis and culicines readily. Hence, it can be used as an alternative mosquito control agent in Ethiopia where the breeding habitats are small and localized.

  17. Simple anthropometric measures correlate with metabolic risk indicators as strongly as magnetic resonance imaging-measured adipose tissue depots in both HIV-infected and control subjects.

    Science.gov (United States)

    Scherzer, Rebecca; Shen, Wei; Bacchetti, Peter; Kotler, Donald; Lewis, Cora E; Shlipak, Michael G; Heymsfield, Steven B; Grunfeld, Carl

    2008-06-01

    Studies in persons without HIV infection have compared percentage body fat (%BF) and waist circumference as markers of risk for the complications of excess adiposity, but only limited study has been conducted in HIV-infected subjects. We compared anthropometric and magnetic resonance imaging (MRI)-based adiposity measures as correlates of metabolic complications of adiposity in HIV-infected and control subjects. The study was a cross-sectional analysis of 666 HIV-positive and 242 control subjects in the Fat Redistribution and Metabolic Change in HIV Infection (FRAM) study assessing body mass index (BMI), waist (WC) and hip (HC) circumferences, waist-to-hip ratio (WHR), %BF, and MRI-measured regional adipose tissue. Study outcomes were 3 metabolic risk variables [homeostatic model assessment (HOMA), triglycerides, and HDL cholesterol]. Analyses were stratified by sex and HIV status and adjusted for demographic, lifestyle, and HIV-related factors. In HIV-infected and control subjects, univariate associations with HOMA, triglycerides, and HDL were strongest for WC, MRI-measured visceral adipose tissue, and WHR; in all cases, differences in correlation between the strongest measures for each outcome were small (r HDL, WC appeared to be the best anthropometric correlate of metabolic complications, whereas, for triglycerides, the best was WHR. Relations of simple anthropometric measures with HOMA, triglycerides, and HDL cholesterol are approximately as strong as MRI-measured whole-body adipose tissue depots in both HIV-infected and control subjects.

  18. Cheyletus eruditus (taurrus): an effective candidate for the biological control of the snake mite (Ophionyssus natricis).

    Science.gov (United States)

    Schilliger, Lionel H; Morel, Damien; Bonwitt, Jesse H; Marquis, Olivier

    2013-09-01

    The most commonly encountered ectoparasite in captive snakes is the hematophagous snake mite (Ophionyssus natricis). Infected snakes often exhibit lethargy, dysecdysis, pruritus, crusting dermatitis (sometimes progressing to abscesses), and behavioral changes (increased bathing time, rubbing against objects). Anemia and septicemia are occasional complications. Eliminating snake mites from a collection is frustrating. Insecticidal and acaricidal compounds used in mammals can be used against O. natricis infestation in reptiles, but they all are potentially neurotoxic to reptiles. The use of a biological agent to control the snake mite was first developed by using the predatory mites Hypoaspis miles and Hypoaspis aculeifer. However, no data are available regarding the potential of these mites to control O. natricis. Furthermore, the survival and predatory behavior of H. aculeifer and H. miles decreases above 28 degrees C, which is the lower value of the optimal temperature zone range required for rearing snakes. The aim of this study is to identify the ability of the predatory mite Cheyletus eruditus to control O. natricis. In the first experiment, 125 O. natricis mites where placed in separate plastic tubes together with the same number of C. eruditus mites. After 48 hr, the survival rate of snake mites was 6% compared with 92% in the control group (n = 125, P snake) ball pythons, with an average of 13 O. natricis per individual, were placed in separate cages with 1,000 C. eruditus mites + vermiculite After 15 days, only an average of two mites per snake remained, compared with 48 per snake in the control group (t-test, P < 0,01).

  19. Biological control of mycotoxin-producing molds Controle biológico de fungos de armazenamento produtores de micotoxinas

    Directory of Open Access Journals (Sweden)

    Flávio Henrique Vasconcelos de Medeiros

    2012-10-01

    Full Text Available Mycotoxins are produced by the secondary metabolism of many fungi and can be found in almost 25% of the world's agricultural commodities. These compounds are toxic to humans, animals, and plants and therefore, efforts should be made to avoid mycotoxin contamination in food and feed. Besides, up to 25% of all harvested fruits and vegetables are lost due to storage molds and/or mycotoxin contamination and many methods have been applied to mitigate these issues, but most of them rely on the use of fungicides. Although chemicals are often the first defensive line against mycotoxigenic fungi, the indiscriminate use of fungicides are awakening the public perception due to their noxious effects on the environment and human/animal health. Thus, there is an increasing public pressure for a safer and eco-friendly alternative to control these organisms. In this background, biological control using microbial antagonists such as bacteria, fungi and yeasts have been shown to be a feasible substitute to reduce the use of chemical compounds. Despite of the positive findings using the biocontrol agents only a few products have been registered and are commercially available to control mycotoxin-producing fungi. This review brings about the up-to-date biological control strategies to prevent or reduce harvested commodity damages caused by storage fungi and the contamination of food and feed by mycotoxins.As micotoxinas são produzidas pelo metabolismo secundário de várias espécies de fungos e podem ser encontradas em quase 25% das commodities agrícolas. Esses compostos são tóxicos a humanos, animais e plantas e, portanto, esforços para evitar a contaminação de micotoxinas em alimentos e rações devem ser feitos. Além disso, até 25% das frutas e legumes em pós-colheita são perdidos em decorrência do ataque de fungos de armazenamento e/ou contaminações por micotoxinas. Vários métodos têm sido aplicados para mitigar os problemas de micotoxinas

  20. Three-way interaction between biological control insects, a congener and their shared parasitoid: Evidence of biotic resistance

    Science.gov (United States)

    Invasive plants are one of the strongest drivers of species extinctions. Weed biological control offers a sustainable and safe means of long-term population reduction of their target. Herbivores introduced for the control of invasive plants interact with the native community in addition to the top-d...

  1. Biological weed control with soil fungi? Antagonistic effects of arbuscular mycorrhizal fungi on the growth of weeds

    NARCIS (Netherlands)

    Veiga, R.

    2012-01-01

    Excessive weed growth represents one of the major threats to crop production especially when reliance on herbicides is reduced. Biological weed control is an alternative, environmentally-sound method that, combined with other weed control practices, can contribute to an effective weed management in

  2. Population-level compensation impedes biological control of an invasive forb and indirect release of a native grass

    Science.gov (United States)

    Yvette K. Ortega; Dean E. Pearson; Lauren P. Waller; Nancy J. Sturdevant; John L. Maron

    2012-01-01

    The intentional introduction of specialist insect herbivores for biological control of exotic weeds provides ideal but understudied systems for evaluating important ecological concepts related to top-down control, plant compensatory responses, indirect effects, and the influence of environmental context on these processes. Centaurea stoebe (spotted knapweed) is a...

  3. Parasitoid inventarisation of European corn borer (Ostrinia nubilalis Hübner, 1796 and options for its biological control in Slovenia

    Directory of Open Access Journals (Sweden)

    Jaka RAZINGER

    2016-04-01

    Full Text Available European corn borer (Ostrinia nubilalis (ECB is an important maize pest in central and northern Europe. Presently it is controlled by insecticides or biological agents such as Trichogramma brassicae in several European countries, excluding Slovenia, where the pest’s pressure is highly variable and no appropriate mechanization is available. Lessening the dependence on chemical pesticides is an integral part of the European Union’s agenda for agriculture. Mass release of Trichogramma spp. could be seen as a promising alternative for ECB control in countries with a highly fluctuating ECB pressure and no mechanization for insecticide applications. However, no records of naturally occurring hymenopteran parasitoids of ECB exist in Slovenia. To address this important under-researched topic and provide the expert basis for potential introduction of ECB egg parasitoids in Slovene maize production, a systematic inventarisation programme of ECB parasitoids was launched in 2010. Additionally, ECB flight was monitored in 2011 and 2012 at two locations in Slovenia: Jablje and Rakičan. In both locations two ECB generations  were observed. ECB was fist observed at the end of May in Rakičan. During the five years of the systematic survey we discovered two ECB parasitoid species. ECB egg masses were parasitized by Trichogramma brassicae, whereas ECB pupae were parasitized by Tycherus nigridens, with 6 or 7 % parasitation rate, respectively. T. nigridens represents a new taxon report for Slovenia. We conclude that there is a strong need for undertaking systematic surveys of natural enemies of agricultural pests.

  4. Using counterfactuals to evaluate the cost-effectiveness of controlling biological invasions.

    Science.gov (United States)

    McConnachie, Matthew M; van Wilgen, Brian W; Ferraro, Paul J; Forsyth, Aurelia T; Richardson, David M; Gaertner, Mirijam; Cowling, Richard M

    2016-03-01

    Prioritizing limited conservation funds for controlling biological invasions requires accurate estimates of the effectiveness of interventions to remove invasive species and their cost-effectiveness (cost per unit area or individual). Despite billions of dollars spent controlling biological invasions worldwide, it is unclear whether those efforts are effective, and cost-effective. The paucity of evidence results from the difficulty in measuring the effect of invasive species removal: a researcher must estimate the difference in outcomes (e.g. invasive species cover) between where the removal program intervened and what might have been observed if the program had not intervened. In the program evaluation literature, this is called a counterfactual analysis, which formally compares what actually happened and what would have happened in the absence of an intervention. When program implementation is not randomized, estimating counterfactual outcomes is especially difficult. We show how a thorough understanding of program implementation, combined with a matching empirical design can improve the way counterfactual outcomes are estimated in nonexperimental contexts. As a practical demonstration, we estimated the cost-effectiveness of South Africa's Working for Water program, arguably the world's most ambitious invasive species control program, in removing invasive alien trees from different land use types, across a large area in the Cape Floristic Region. We estimated that the proportion of the treatment area covered by invasive trees would have been 49% higher (5.5% instead of 2.7% of the grid cells occupied) had the program not intervened. Our estimates of cost per hectare to remove invasive species, however, are three to five times higher than the predictions made when the program was initiated. Had there been no control (counter-factual), invasive trees would have spread on untransformed land, but not on land parcels containing plantations or land transformed by

  5. Healthy Children, Strong Families 2: A randomized controlled trial of a healthy lifestyle intervention for American Indian families designed using community-based approaches.

    Science.gov (United States)

    Tomayko, Emily J; Prince, Ronald J; Cronin, Kate A; Parker, Tassy; Kim, Kyungmann; Grant, Vernon M; Sheche, Judith N; Adams, Alexandra K

    2017-04-01

    Background/Aims Few obesity prevention trials have focused on young children and their families in the home environment, particularly in underserved communities. Healthy Children, Strong Families 2 is a randomized controlled trial of a healthy lifestyle intervention for American Indian children and their families, a group at very high risk of obesity. The study design resulted from our long-standing engagement with American Indian communities, and few collaborations of this type resulting in the development and implementation of a randomized clinical trial have been described. Methods Healthy Children, Strong Families 2 is a lifestyle intervention targeting increased fruit and vegetable intake, decreased sugar intake, increased physical activity, decreased TV/screen time, and two less-studied risk factors: stress and sleep. Families with young children from five American Indian communities nationwide were randomly assigned to a healthy lifestyle intervention ( Wellness Journey) augmented with social support (Facebook and text messaging) or a child safety control group ( Safety Journey) for 1 year. After Year 1, families in the Safety Journey receive the Wellness Journey, and families in the Wellness Journey start the Safety Journey with continued wellness-focused social support based on communities' request that all families receive the intervention. Primary (adult body mass index and child body mass index z-score) and secondary (health behaviors) outcomes are assessed after Year 1 with additional analyses planned after Year 2. Results To date, 450 adult/child dyads have been enrolled (100% target enrollment). Statistical analyses await trial completion in 2017. Lessons learned Conducting a community-partnered randomized controlled trial requires significant formative work, relationship building, and ongoing flexibility. At the communities' request, the study involved minimal exclusion criteria, focused on wellness rather than obesity, and included an active

  6. Microbiological control of sterilization efficiency by irradiation. Biological indicators. [Medical supplies

    Energy Technology Data Exchange (ETDEWEB)

    Bates, C [Institut National des Radioelements, Brussels (Belgium)

    1977-01-01

    The microbiological efficiency of the radiosterilization process was tested by means of biological indicators such as Micrococcus radiodurans R1 and Bacillus pumilus E601 for gamma and electron radiation doses ranging from 0.5 to 6 Mrad. The response of the biological indicators was studied in terms of conservation time, initial concentration of biological material, and sources of used radiation. Both the biological dosimetry of the process and the sterility after treatment were studied on the basis of inactivation curves.

  7. Hyporheic Interfaces Serve as Ecological Control Points for Mountainous Landscape Biological Productivity

    Science.gov (United States)

    Newcomer, M. E.; Dwivedi, D.; Raberg, J.; Fox, P. M.; Nico, P. S.; Wainwright, H. M.; Conrad, M. E.; Bill, M.; Bouskill, N.; Williams, K. H.; Hubbard, S.; Steefel, C. I.

    2017-12-01

    lengthened vernal window motivates a better understanding of the role each ecological control point plays in processing landscape biological productivity and for understanding biogeochemical cycling in riverine systems.

  8. Psychological trauma symptoms and Type 2 diabetes prevalence, glucose control, and treatment modality among American Indians in the Strong Heart Family Study.

    Science.gov (United States)

    Jacob, Michelle M; Gonzales, Kelly L; Calhoun, Darren; Beals, Janette; Muller, Clemma Jacobsen; Goldberg, Jack; Nelson, Lonnie; Welty, Thomas K; Howard, Barbara V

    2013-01-01

    The aims of this paper are to examine the relationship between psychological trauma symptoms and Type 2 diabetes prevalence, glucose control, and treatment modality among 3776 American Indians in Phase V of the Strong Heart Family Study. This cross-sectional analysis measured psychological trauma symptoms using the National Anxiety Disorder Screening Day instrument, diabetes by American Diabetes Association criteria, and treatment modality by four categories: no medication, oral medication only, insulin only, or both oral medication and insulin. We used binary logistic regression to evaluate the association between psychological trauma symptoms and diabetes prevalence. We used ordinary least squares regression to evaluate the association between psychological trauma symptoms and glucose control. We used binary logistic regression to model the association of psychological trauma symptoms with treatment modality. Neither diabetes prevalence (22%-31%; p=0.19) nor control (8.0-8.6; p=0.25) varied significantly by psychological trauma symptoms categories. However, diabetes treatment modality was associated with psychological trauma symptoms categories, as people with greater burden used either no medication, or both oral and insulin medications (odds ratio=3.1, ppsychological trauma symptoms suggests future research investigate patient and provider treatment decision making. © 2013.

  9. Biological control of Indianmeal moth (Lepidoptera: Pyralidae) on finished stored products using egg and larval parasitoids.

    Science.gov (United States)

    Grieshop, Matthew J; Flinn, Paul W; Nechols, James R

    2006-08-01

    Biological control using hymenopteran parasitoids presents an attractive alternative to insecticides for reducing infestations and damage from the Indianmeal moth, Plodia interpunctella (Hübner) (Lepidoptera: Pyralidae), in retail and warehouse environments. We examined the potential for using combinations of the egg parasitoid Trichogramma deion Riley (Hymenoptera: Trichogrammatidae), and the larval parasitoid Habrobracon hebetor (Say) (Hymenoptera: Braconidae) for preventing infestations of P. interpunctella in coarse-ground cornmeal as well as the influence of packaging on parasitoid effectiveness. Treatments included one or both parasitoids and either cornmeal infested with P. interpunctella eggs or eggs deposited on the surface of plastic bags containing cornmeal. H. hebetor had a significant impact on the number of live P. interpunctella, suppressing populations by approximately 71% in both unbagged and bagged cornmeal. In contrast, T. deion did not suppress P. interpunctella in unbagged cornmeal. However, when released on bagged cornmeal, T. deion significantly increased the level of pest suppression (87%) over bagging alone (15%). When H. hebetor was added to bagged cornmeal, there was a significant reduction of live P. interpunctella compared with the control (70.6%), with a further reduction observed when T. deion was added (96.7%). These findings suggest that, in most situations, a combined release of both T. deion and H. hebetor would have the greatest impact; because even though packaging may protect most of the stored products, there are usually areas in the storage landscape where poor sanitation is present.

  10. Screening of chitinolytic actinomycetes for biological control of Sclerotium rolfsii stem rot disease of chilli

    Directory of Open Access Journals (Sweden)

    Pranee Pattanapipitpaisal

    2012-09-01

    Full Text Available Two hundred and eighty three strains were isolated from rhizoshere-associated soils, from Ubon Ratchathani andSrisaket province, using Enrichment Media for isolation of Chitinase-producing Actinomycetes agar (EMCA agar. All strainswere screened for chitinolytic activity and sixty eight strains gave significant clear zone on EMCA agar plates. The selectedchitinolytic strains were assayed for in vitro antagonism against Sclerotium rolfsii using cornmeal agar (CMA agar assayprocedure and the result showed that thirteen isolates have remarkable inhibiting the growth of the fungus and the top fiveantagonistic actinomycetes were PACCH 277, PACCH129, PACCH225, PACCH24 and PACCH246, respectively. The resultindicated that these actinomycetes produce chitinase which catalyze the degradation of chitin, resulting in inhibition of S.rolfsii growth. Their abilities to control the disease development were tested for in vivo biocontrol assay on chilli seedlings.Two out of thirteen candidate, PACCH24 and PACCH225, antagonists reduced the disease development at 90%. It wassuggested that the ability to inhibit the growth of pathogen in vitro was not related to the disease reduction in vivo. Thestrain PACCH24 was further identified as Streptomyces hygroscopicus according to morphological characteristic, cell walland cellular sugar analysis and 16S rDNA sequencing. The study implies a novel chitinolytic actinomycete which could bedeveloped to be a biological agent which would be included as a complement with organic fertilizers in order to control stemrot disease and promote growth of chilli.

  11. Evaluation of biological control of fusarium wilt in gerbera with Trichoderma asperellum

    Directory of Open Access Journals (Sweden)

    Daiani Brandler

    2017-09-01

    Full Text Available The increase in flower cultivation in recent years has been reflecting the higher incidence of soil pathogens that can cause serious problems. This study aimed to evaluate the biological control of Fusarium wilt in gerbera with Trichoderma asperellum. The evaluated treatments were: T1 Control, only sterile substrate; T2 Substrate + Fusarium oxysporum; T3 Substrate + Fusarium oxysporum + Trichoderma asperellum; and T4 Substrate + Trichoderma asperellum. For this, the pathogen was isolated from gerbera with disease symptoms and, subsequently, it was identified according to morphological characters. Furthermore, the degree of antagonism of T. asperellum against F. oxysporum was evaluated through the culture pairing test. For greenhouse evaluations, commercial autoclaved substrate was used and infested with corn grains infected by the pathogen. Morphological identification confirmed the pathogen species as Fusarium oxysporum. In the culture pairing test, it was found that T. asperellum did not present a high degree of antagonism. The plants cultivated on substrate infested by the pathogen had no visible symptoms of wilt, but the substrate infestation with the pathogen provided lower values of fresh and dry mass of shoots and roots. The treatment with T. asperellum obtained higher values of fresh and dry mass of both shoots and roots, and also more vigorous inflorescences in relation to the plants treated with the pathogen

  12. Biological insecticides for the control Spodoptera frugiperda Smith, its incidence on yield

    Directory of Open Access Journals (Sweden)

    Xavier Cayetano Muñoz Conforme

    2017-10-01

    Full Text Available The work was carried out in farmers' fields of located in the area of Portoviejo, province of Manabí; with the objective of evaluating two biological insecticides, Methakill and Baukill with doses of 5, 10 and 15 mL L-1 of water for the control of S. frugiperda, being evaluated the populations of the insect before and after the application of the same. A Full Random Block Design was used, with three replicates. The chemical treatment (Lambda Cyhalothrin + Tiametoxan 1.5 mL L-1 of water presented the lowest averages of damage (6.47 %, followed by the treatment that consisted of the spraying of Methakill in doses of 15 mL L-1 water with 10.57 % damage. The Control treatment had the highest percentages of involvement with 27.78 %. The highest yields were obtained in the treatments where Lambda Cyhalothrin + Tiametoxan 1.5 mL L-1 water and Methakill 15 mL L-1 water were applied, statistically equal to each other with 7989.24 and 6919.43 kg ha-1 respectively. The best Marginal Return Rate was obtained using the Methakill treatment 15 mL L-1 of water with 1043.45 %.

  13. Biological nitrogen fixation: rates, patterns and ecological controls in terrestrial ecosystems

    Science.gov (United States)

    Vitousek, Peter M.; Menge, Duncan N.L.; Reed, Sasha C.; Cleveland, Cory C.

    2013-01-01

    New techniques have identified a wide range of organisms with the capacity to carry out biological nitrogen fixation (BNF)—greatly expanding our appreciation of the diversity and ubiquity of N fixers—but our understanding of the rates and controls of BNF at ecosystem and global scales has not advanced at the same pace. Nevertheless, determining rates and controls of BNF is crucial to placing anthropogenic changes to the N cycle in context, and to understanding, predicting and managing many aspects of global environmental change. Here, we estimate terrestrial BNF for a pre-industrial world by combining information on N fluxes with 15N relative abundance data for terrestrial ecosystems. Our estimate is that pre-industrial N fixation was 58 (range of 40–100) Tg N fixed yr−1; adding conservative assumptions for geological N reduces our best estimate to 44 Tg N yr−1. This approach yields substantially lower estimates than most recent calculations; it suggests that the magnitude of human alternation of the N cycle is substantially larger than has been assumed.

  14. Screening of bacterial antagonists for biological control of Phytophthora blight of pepper.

    Science.gov (United States)

    Rajkumar, M; Lee, Wang Hyu; Lee, Kui Jae

    2005-01-01

    The aim of this study was to assess the potential of bacterial antagonists to control Phytophthora blight of pepper caused by P. capsici using different screening methods. Among a collection of fluorescent pseudomonas isolated from the rhizosphere of pepper, twelve isolates were initially selected based on dual culture assay on potato dextrose agar and corn meal agar. Further, these twelve isolates were screened for the reduction of disease severity caused by P. capsici using detached leaves and seedling assay. Most of the antagonists showed varying levels of antagonism against P. capsici in both detached leaves and seedlings assay. In addition, few isolates increased shoot and root length of pepper in seedling assays. Among them, isolate PS119 showing highest ability to reduce the disease severity in the in vitro seedling assay was found to be the most efficient antagonists against P. capsici in the in vivo biological control tests. These results indicate that the in vitro seedling assay can be used as a rapid and more accurate technique for the selection of promising biocontrol agents against P. capsici. ((c) 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim).

  15. A biologically inspired controller to solve the coverage problem in robotics.

    Science.gov (United States)

    Rañó, Iñaki; Santos, José A

    2017-06-05

    The coverage problem consists on computing a path or trajectory for a robot to pass over all the points in some free area and has applications ranging from floor cleaning to demining. Coverage is solved as a planning problem-providing theoretical validation of the solution-or through heuristic techniques which rely on experimental validation. Through a combination of theoretical results and simulations, this paper presents a novel solution to the coverage problem that exploits the chaotic behaviour of a simple biologically inspired motion controller, the Braitenberg vehicle 2b. Although chaos has been used for coverage, our approach has much less restrictive assumptions about the environment and can be implemented using on-board sensors. First, we prove theoretically that this vehicle-a well known model of animal tropotaxis-behaves as a charge in an electro-magnetic field. The motion equations can be reduced to a Hamiltonian system, and, therefore the vehicle follows quasi-periodic or chaotic trajectories, which pass arbitrarily close to any point in the work-space, i.e. it solves the coverage problem. Secondly, through a set of extensive simulations, we show that the trajectories cover regions of bounded workspaces, and full coverage is achieved when the perceptual range of the vehicle is short. We compare the performance of this new approach with different types of random motion controllers in the same bounded environments.

  16. Biological soil crust and disturbance controls on surface hydrology in a semi-arid ecosystem

    Science.gov (United States)

    Faist, Akasha M; Herrick, Jeffrey E.; Belnap, Jayne; Van Zee, Justin W; Barger, Nichole N

    2017-01-01

    Biological soil crust communities (biocrusts) play an important role in surface hydrologic processes in dryland ecosystems, and these processes may then be dramatically altered with soil surface disturbance. In this study, we examined biocrust hydrologic responses to disturbance at different developmental stages on sandy soils on the Colorado Plateau. Our results showed that all disturbance (trampling, scalping and trampling+scalping) of the early successional light cyanobacterial biocrusts generally reduced runoff. In contrast, trampling well-developed dark-cyano-lichen biocrusts increased runoff and sediment loss relative to intact controls. Scalping did not increase runoff, implying that soil aggregate structure was important to the infiltration process. Well-developed, intact dark biocrusts generally had lower runoff, low sediment loss, and highest aggregate stability whereas the less-developed light biocrusts were highest in runoff and sediment loss when compared to the controls. These results suggest the importance of maintaining the well-developed dark biocrusts, as they are beneficial for lowering runoff and reducing soil loss and redistribution on the landscape. These data also suggest that upslope patches of light biocrust may either support water transport to downslope vegetation patches or alternatively this runoff may place dark biocrust patches at risk of disruption and loss, given that light patches increase runoff and thus soil erosion potential.

  17. High blood pressure in Panama: prevalence, sociodemographic and biologic profile, treatment, and control (STROBE).

    Science.gov (United States)

    Mc Donald Posso, Anselmo J; Motta Borrel, Jorge A; Fontes, Flavia; Cruz Gonzalez, Clara E; Pachón Burgos, Alvaro A; Cumbrera Ortega, Alberto

    2014-11-01

    The objective of this study is to estimate the prevalence, treatment, and control of high blood pressure, hypertension (HBP) in Panama and assess its associations with sociodemographic and biologic factors.A cross-sectional, descriptive study was conducted in Panama by administering a survey on cardiovascular risk factors to 3590 adults and measuring their blood pressure 3 times. A single-stage, probabilistic, and randomized sampling strategy with a multivariate stratification was used. The average blood pressure, confidence intervals (CIs), odds ratio (OR), and a value of P ≤ 0.05 were used for the analysis.The estimated prevalence of HBP was 29.6% (95% CI, 28.0-31.1); it was more prevalent in men than in women, OR = 1.37 (95% CI, 1.17-1.61); it increased with age and was more frequent among Afro-Panamanians (33.8%). HBP was associated with a family history of HBP with being physically inactive and a body mass index ≥25.0 kg/m or a waist circumference >90 cm in men and >88 cm in women (P control (<140/90 mm Hg).HBP is the most common cardiovascular risk factor among Panamanians and consequently an important public health problem in Panama. The health care system needs to give a high priority to HBP prevention programs and integrated care programs aimed at treating HBP, taking into consideration the changes in behavior that have been brought about by alterations in nutrition and sedentary lifestyles.

  18. Interactive effects of chemical and biological controls on food-web composition in saline prairie lakes.

    Science.gov (United States)

    Cooper, Ryan N; Wissel, Björn

    2012-11-27

    Salinity is restricting habitatability for many biota in prairie lakes due to limited physiological abilities to cope with increasing osmotic stress. Yet, it remains unclear how salinity effects vary among major taxonomic groups and what role other environmental parameters play in shaping food-web composition. To answer these questions, we sampled fish, zooplankton and littoral macroinvertebrates in 20 prairie lakes (Saskatchewan, Canada) characterized by large gradients in water chemistry and lake morphometry. We showed that salinity thresholds differed among major taxonomic groups, as most fishes were absent above salinities of 2 g L-1, while littoral macroinvertebrates were ubiquitous. Zooplankton occurred over the whole salinity range, but changed taxonomic composition as salinity increased. Subsequently, the complexity of fish community (diversity) was associated with large changes in invertebrate communities. The directional changes in invertebrate communities to smaller taxa indicated that complex fish assemblages resulted in higher predation pressure. Most likely, as the complexity of fish community decreased, controls of invertebrate assemblages shifted from predation to competition and ultimately to productivity in hypersaline lakes. Surprisingly, invertebrate predators did not thrive in the absence of fishes in these systems. Furthermore, the here identified salinity threshold for fishes was too low to be a result of osmotic stress. Hence, winterkill was likely an important factor eliminating fishes in low salinity lakes that had high productivity and shallow water depth. Ultimately, while salinity was crucial, intricate combinations of chemical and biological mechanisms also played a major role in controlling the assemblages of major taxonomic groups in prairie lakes.

  19. Dengue: Vector Biology, Transmission and Control Options in Mexico (El Dengue: Binomia Del Vector, Transmision y Opciones Para su Control en Mexico)

    Science.gov (United States)

    1990-01-01

    on August 2, 1989. Filiberto Reyes Villanueva, M.S., studied biology at the School of Biological Sciences of the Autonomous Universi- ty of Nueva Le6n...experts (1987), are the entomopathogenic bacteria Bacillus thuringiensis, serotype H-14 and B. sphaericus. These microorgan- isms can operate only...the country, as is the case with A. aegypti. These bacteria offer a potential for the control of those vectors which have already developed a

  20. Structure and behavior as determinants: United States nuclear test ban and chemical and biological arms control policy

    International Nuclear Information System (INIS)

    Reich, J.C.

    1991-01-01

    US efforts to control chemical and biological warfare and nuclear testing are examined with the aim of explaining the paucity of US backed agreements in these areas. Two theoretical perspectives, the behavioral and structural approaches, are used to explore US arms control outcomes. In the behavioral approach, the effects of governmental organization and the bargaining dynamics of policy-making elites with different cognitive styles are posited as important influences on US nuclear test ban and chemical and biological arms control policy outcomes. The behavioral perspective accounts for the timing of all US failed and successful entries (with one exception) into nuclear test bans and chemical and biological warfare restraints. A shortcoming of the behavior approach, however, is that it tends to overemphasize the chances for successful US entry into nuclear test and chemical and biological warfare limitations. Analysis of the same events from the structural perspective helps to correct for expectations generated by behavioral variables for a higher success rate than ultimately resulted. In the structural approach, the focus is on the effect of the organization of international politics on US nuclear test ban and chemical and biological arms control policy outcomes

  1. Utilization of biological control agents for the management of postharvest pathogens of tomato

    International Nuclear Information System (INIS)

    Zafar, M.U.; Ansari, S.U.

    2016-01-01

    Twenty five isolates of Trichoderma, Bacillus and Pseudomonas spp. were obtained from rhizosphere of tomato growing fields using soil dilution technique on potato dextrose agar (PDA) and nutrient agar (NA) medium. Screening of these isolates were done against Geotrichum candidum, Trichothecium roseum and Rhizopus oryzae, causal agents of sour rot, pink mold rot and Rhizopus soft rot of tomato under the laboratory conditions. One promising isolate of each Trichoderma harzianum, Bacillus spp. and Pseudomonas fluorescens from the twenty five isolates were chosen and further evaluated as potential biological control agents (BCAs) against three important postharvest pathogens of tomato. Dual culture and spore concentration assay revealed that all three isolates inhibited radial growth of G. candidum, T. roseum and R. oryzae. Tomato fruits were inoculated with 25 micro L suspension of 10/sup 8/ cfu mL-1 for T. harzianum and 10/sup 8/cfu mL-1for each Bacillus sp. and P. fluorescens. Twenty four hours later the treated fruits were inoculated with 25 micro L of 105 conidia/mL of each of three postharvest pathogens. The results showed that P. fluorescens provided good control (78.1%) of G. candidum and (82.2%) R. oryzae, while, T. harzianum proved less effective to control all three pathogens. Bacillus spp. was only effective (88.4%) against T. roseum. Hence, our results depicted that Bacillus spp. and P. fluorescens proved to be a potential antagonist of T. roseum and R. oryzae however, all the tested BCAs were not consistent in their action against three postharvest pathogens of tomato. (author)

  2. Cost-Benefit Analysis for Biological Control Programs That Targeted Insect Pests of Eucalypts in Urban Landscapes of California.

    Science.gov (United States)

    Paine, T D; Millar, J G; Hanks, L M; Gould, J; Wang, Q; Daane, K; Dahlsten, D L; Mcpherson, E G

    2015-12-01

    As well as being planted for wind breaks, landscape trees, and fuel wood, eucalypts are also widely used as urban street trees in California. They now are besieged by exotic insect herbivores of four different feeding guilds. The objective of the current analysis was to determine the return on investment from biological control programs that have targeted these pests. Independent estimates of the total number of eucalypt street trees in California ranged from a high of 476,527 trees (based on tree inventories from 135 California cities) to a low of 190,666 trees (based on 49 tree inventories). Based on a survey of 3,512 trees, the estimated mean value of an individual eucalypt was US$5,978. Thus, the total value of eucalypt street trees in California ranged from more than US$1.0 billion to more than US$2.8 billion. Biological control programs that targeted pests of eucalypts in California have cost US$2,663,097 in extramural grants and University of California salaries. Consequently, the return derived from protecting the value of this resource through the biological control efforts, per dollar expended, ranged from US$1,070 for the high estimated number of trees to US$428 for the lower estimate. The analyses demonstrate both the tremendous value of urban street trees, and the benefits that stem from successful biological control programs aimed at preserving these trees. Economic analyses such as this, which demonstrate the substantial rates of return from successful biological control of invasive pests, may play a key role in developing both grass-roots and governmental support for future urban biological control efforts. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  3. Simple anthropometric measures correlate with metabolic risk indicators as strongly as magnetic resonance imaging–measured adipose tissue depots in both HIV-infected and control subjects2

    Science.gov (United States)

    Scherzer, Rebecca; Shen, Wei; Bacchetti, Peter; Kotler, Donald; Lewis, Cora E; Shlipak, Michael G; Heymsfield, Steven B

    2008-01-01

    Background Studies in persons without HIV infection have compared percentage body fat (%BF) and waist circumference as markers of risk for the complications of excess adiposity, but only limited study has been conducted in HIV-infected subjects. Objective We compared anthropometric and magnetic resonance imaging (MRI)–based adiposity measures as correlates of metabolic complications of adiposity in HIV-infected and control subjects. Design The study was a cross-sectional analysis of 666 HIV-positive and 242 control subjects in the Fat Redistribution and Metabolic Change in HIV Infection (FRAM) study assessing body mass index (BMI), waist (WC) and hip (HC) circumferences, waist-to-hip ratio (WHR), %BF, and MRI-measured regional adipose tissue. Study outcomes were 3 metabolic risk variables [homeostatic model assessment (HOMA), triglycerides, and HDL cholesterol]. Analyses were stratified by sex and HIV status and adjusted for demographic, lifestyle, and HIV-related factors. Results In HIV-infected and control subjects, univariate associations with HOMA, triglycerides, and HDL were strongest for WC, MRI-measured visceral adipose tissue, and WHR; in all cases, differences in correlation between the strongest measures for each outcome were small (r ≤ 0.07). Multivariate adjustment found no significant difference for optimally fitting models between the use of anthropometric and MRI measures, and the magnitudes of differences were small (adjusted R2 ≤ 0.06). For HOMA and HDL, WC appeared to be the best anthropometric correlate of metabolic complications, whereas, for triglycerides, the best was WHR. Conclusion Relations of simple anthropometric measures with HOMA, triglycerides, and HDL cholesterol are approximately as strong as MRI-measured whole-body adipose tissue depots in both HIV-infected and control subjects. PMID:18541572

  4. First Attempt at and Early Results on the Biological Control of Pistia stratiotes L. in South Africa

    Directory of Open Access Journals (Sweden)

    Catharina J. Cilliers

    1987-10-01

    Full Text Available Although Pistia stratiotes L. (water lettuce is not an important weed in the Republic of South Africa, the host-specific weevil Neohydronomus pulchellus Hustache was imported for the biological control of this weed. The weevil was released onto a dense infestation of P. stratiotes of several years standing on a pan in the Pafuri area in December 1985. By September 1986 the weevils had already destroyed most of the weed and in October 1986 the weed was under biological control at this site.

  5. Quality controls in integrative approaches to detect errors and inconsistencies in biological databases

    Directory of Open Access Journals (Sweden)

    Ghisalberti Giorgio

    2010-12-01

    Full Text Available Numerous biomolecular data are available, but they are scattered in many databases and only some of them are curated by experts. Most available data are computationally derived and include errors and inconsistencies. Effective use of available data in order to derive new knowledge hence requires data integration and quality improvement. Many approaches for data integration have been proposed. Data warehousing seams to be the most adequate when comprehensive analysis of integrated data is required. This makes it the most suitable also to implement comprehensive quality controls on integrated data. We previously developed GFINDer (http://www.bioinformatics.polimi.it/GFINDer/, a web system that supports scientists in effectively using available information. It allows comprehensive statistical analysis and mining of functional and phenotypic annotations of gene lists, such as those identified by high-throughput biomolecular experiments. GFINDer backend is composed of a multi-organism genomic and proteomic data warehouse (GPDW. Within the GPDW, several controlled terminologies and ontologies, which describe gene and gene product related biomolecular processes, functions and phenotypes, are imported and integrated, together with their associations with genes and proteins of several organisms. In order to ease maintaining updated the GPDW and to ensure the best possible quality of data integrated in subsequent updating of the data warehouse, we developed several automatic procedures. Within them, we implemented numerous data quality control techniques to test the integrated data for a variety of possible errors and inconsistencies. Among other features, the implemented controls check data structure and completeness, ontological data consistency, ID format and evolution, unexpected data quantification values, and consistency of data from single and multiple sources. We use the implemented controls to analyze the quality of data available from several

  6. [An example of research on biological control: Entomophthora fungi pathogenic for aphids].

    Science.gov (United States)

    Latgé, J P; Remaudière, G; Papierok, B

    1978-01-01

    The results obtained in 15 years of research on the Entomophthorales pathogen of aphids showed the importance of the action of these fungi in the regulation of natural aphid populations and their possible use in agriculture as a biological control agent. Recent ecological studies on natural populations of aphids established the seasonal variation of the different fungal species and the diverse degrees of specificity between the species or groups of species of aphid and the various species of Entomophthora. The study of populations dynamics of an aphid species on a cultivated plant permitted the determination of the way a certain number of biotic and abiotic factors, such as temperature, humidity, thresholds of the insect population and of the infecting fungus lead to an epizootic development. If the air propagation of the disease by conidia is understood for a long time, the role of the soil as a reservoir for the infecting fungus has been demonstrated recently. Under favourable climatic conditions, the use of industrially produced resistant resting spores would allow the regulation of aphid populations in nature.

  7. Biological control program is being developed for brown marmorated stink bug

    Directory of Open Access Journals (Sweden)

    Jesus Lara

    2016-01-01

    Full Text Available Brown marmorated stink bug (BMSB is an invasive, polyphagous pest that has been detected in 42 U.S. states. In 2010, it caused millions of dollars in crop damages to apple growers on the East Coast, where it arrived from Asia during the 1990s. In 2002, BMSB was reported in California; since then, it has been detected in 28 counties and is established in at least nine counties. Although this pest has not yet been found on commercial crops in the state, detections of BMSB in commercial orchards have been documented in Oregon and Washington. Proactive research in California has joined national efforts led by U.S. Department of Agriculture researchers to develop a classical biological control program for BMSB. A study is under way to determine potential non-target effects of a specialist egg parasitoid, Trissolcus japonicus (Hymenoptera: Platygastridae, imported from Beijing, China, part of the home range of BMSB. In addition, the role of BMSB natural enemies residing in California is being assessed. A review of the recent research outlines the possible opportunities for reducing the threat BMSB poses to California.

  8. Ants: Major Functional Elements in Fruit Agro-Ecosystems and Biological Control Agents

    Directory of Open Access Journals (Sweden)

    Lamine Diamé

    2017-12-01

    Full Text Available Ants are a very diverse taxonomic group. They display remarkable social organization that has enabled them to be ubiquitous throughout the world. They make up approximately 10% of the world’s animal biomass. Ants provide ecosystem services in agrosystems by playing a major role in plant pollination, soil bioturbation, bioindication, and the regulation of crop-damaging insects. Over recent decades, there have been numerous studies in ant ecology and the focus on tree cropping systems has given added importance to ant ecology knowledge. The only missing point in this knowledge is the reasons underlying difference between the positive and negative effects of ants in tree cropping systems. This review article provides an overview of knowledge of the roles played by ants in orchards as functional elements, and on the potential of Oecophylla weaver ants as biological control agents. It also shows the potential and relevance of using ants as an agro-ecological diagnosis tool in orchards. Lastly, it demonstrates the potential elements which may determine the divergent negative and positive of their effects on cropping systems.

  9. Aspergillus alliaceus, a new potential biological control of the root parasitic weed Orobanche.

    Science.gov (United States)

    Aybeke, Mehmet; Sen, Burhan; Okten, Suzan

    2014-07-01

    During extensive surveys in fields heavily infested by broomrape in the Trakya Region-Turkey, a different new fungus, Aspergillus alliaceus, was isolated from the infected broomrape. It is aimed to investigate whether or not it is really a pathogen for Orobanche. The fungi was exposed to a greenhouse environment in order to assess its pathogenicity and virulence against Orobanche cernua. In addition, infection tests on Orobanche seeds were also performed under laboratory conditions. The fungus was subjected using two different methods, exposure to a liquid culture with conidial solution and a sclerotial solid culture with fungal mycelia. Cytological studies were carried out at light, TEM and SEM levels. The results show that the sclerotial solid culture with fungal mycelia quickly caused necrosis and was more effective than the other type. It also greatly diminished attachments, tubercles, and caused the emergence of shoots and an increase in the total shoot number of Orobanche. In addition, both when the fungi was exposed to both soil and used to contaminate sunflower seeds, its pathogenicity was more effective. Consequently, it was determined that A. alliaceus was an effective potential biological control of broomrape throughout its life cycle from dormant seed to mature plant. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Modes of action for biological control of Botrytis cinerea by antagonistic bacteria

    Directory of Open Access Journals (Sweden)

    Rana HAIDAR

    2017-01-01

    Full Text Available The role of beneficial bacteria in biocontrol of plant diseases, particularly those caused by the necrotrophic fungus Botrytis cinerea, has been investigated by testing many bacteria under laboratory and field conditions. Bacteria may protect plants against B. cinerea by direct antagonistic interactions between biocontrol agents and this pathogen, as well as indirect effects through the induction of host resistance. This review focuses on various bacteria that act as biological control agents (BCAs of B. cinerea and their associated mechanisms. The modes of action (MoAs include: i synthesis of anti-fungal metabolites, such as antibiotics, cell wall-degrading enzymes and volatile organic compounds (VOCs; ii competition for nutrients and/or a niche; and iii induction of host resistance. The challenge for development of BCAs is to reduce the variability of efficiency and to prove persistence under a large range of conditions. We discuss the advantages and drawbacks of MoA for future applications of bacteria in the field and in post-harvest storage, as well as combination of different MoAs as a strategy to achieve a more regular efficacy.

  11. BIOLOGY AND CONTROL OF THE APPLE MEALYBUG PHENACOCCUS ACERIS (SIGNORET) IN BELGIUM.

    Science.gov (United States)

    Bangels, E; Peusens, G; Bylemans, D; Belien, T

    2014-01-01

    Although in general very rare, some outbreaks of the apple mealybug Phenococcus aceris (Signoret) (Hemiptera: Pseudococcidae) were reported in the Belgian fruit growing area recently. This insect is known to be geographically widespread, to have a broad host range and to infest apple trees. Damage at harvest is considerable when sooty molds, a consequence of the pest's honeydew production, cover the fruits. Indirect damage of an infection is caused in cherry cultivation through transmission of the Little cherry virus (LChV2). Efficacy trials were executed in infested apple orchards in the Belgian fruit growing area and the life cycle of the pest on apple was studied more into detail. Apple mealybugs are univoltine, overwinter as 2nd instar nymphs inside a white cocoon on the tree (under the bark, in crevices) and leave their overwintering site in early spring (mid March). On sunny days the nymphs become active, move around and attach to start feeding (mid April). After a final moult into the adult form, females lay eggs in a cocoon-like white structure (from flowering on). Following hatching (end May), massive numbers of young nymphs spread out on the underside of the leaves (mid June) where they feed through suction. In order to manage this pest the efficacy of several plant protection products was tested in two infested apple orchards. Results indicated that mortality was high after an application of compounds belonging to the neonicotinoid insecticides. Different application timings and control strategies are possible, with active nymphs being the most vulnerable life stage. The observed degree of parasitation in our trial orchards also indicates a biological control contribution of parasitic wasps that should be taken into account. A decent IPM-strategy based on our results solved the problem in both apple orchards.

  12. Biology, etiology, and control of virus diseases of banana and plantain.

    Science.gov (United States)

    Kumar, P Lava; Selvarajan, Ramasamy; Iskra-Caruana, Marie-Line; Chabannes, Matthieu; Hanna, Rachid

    2015-01-01

    Banana and plantain (Musa spp.), produced in 10.3 million ha in the tropics, are among the world's top 10 food crops. They are vegetatively propagated using suckers or tissue culture plants and grown almost as perennial plantations. These are prone to the accumulation of pests and pathogens, especially viruses which contribute to yield reduction and are also barriers to the international exchange of germplasm. The most economically important viruses of banana and plantain are Banana bunchy top virus (BBTV), a complex of banana streak viruses (BSVs) and Banana bract mosaic virus (BBrMV). BBTV is known to cause the most serious economic losses in the "Old World," contributing to a yield reduction of up to 100% and responsible for a dramatic reduction in cropping area. The BSVs exist as episomal and endogenous forms are known to be worldwide in distribution. In India and the Philippines, BBrMV is known to be economically important but recently the virus was discovered in Colombia and Costa Rica, thus signaling its spread into the "New World." Banana and plantain are also known to be susceptible to five other viruses of minor significance, such as Abaca mosaic virus, Abaca bunchy top virus, Banana mild mosaic virus, Banana virus X, and Cucumber mosaic virus. Studies over the past 100 years have contributed to important knowledge on disease biology, distribution, and spread. Research during the last 25 years have led to a better understanding of the virus-vector-host interactions, virus diversity, disease etiology, and epidemiology. In addition, new diagnostic tools were developed which were used for surveillance and the certification of planting material. Due to a lack of durable host resistance in the Musa spp., phytosanitary measures and the use of virus-free planting material are the major methods of virus control. The state of knowledge on BBTV, BBrMV, and BSVs, and other minor viruses, disease spread, and control are summarized in this review. © 2015 Elsevier Inc

  13. Invading freshwater snails and biological control in Martinique Island, French West Indies

    Directory of Open Access Journals (Sweden)

    Jean-Pierre Pointier

    2001-09-01

    Full Text Available Eight alien freshwater snail species were introduced into Martinique Island during the last 50 years. The introduced snails include four planorbids (Biomphalaria straminea, Helisoma duryi, Amerianna carinata and Gyraulus sp., three thiarids (Melanoides tuberculata, M. amabilis and Tarebia granifera and one ampullarid (Marisa cornuarietis. Four of these species rapidly colonized the whole Martinican hydrographic system whereas the other four remained restricted to some particular sites. The invasion processes were documented during the last 20 years and showed (i a rapid invasion of the island by several morphs of M. tuberculata at the beginning of the 80's; (ii the introduction of T. granifera in 1991 and M. amabilis in 1997; and (iii the rapid spread of these last two species throughout the island. In the years following its introduction, M. tuberculata was used in biological control experiments against the snail hosts of schistosomiasis, B. glabrata and B. straminea. Experiments were conducted with success in several groups of water-cress beds which constituted the latest transmission sites for schistosomiasis at the beginning of the 80's. A malacological survey carried out in 2000 all over the island showed the absence of B. glabrata but the presence of some residual populations of B. straminea. Long-term studies carried out in Martinique have shown that the thiarids are able to maintain relatively stable populations over a long period of time, thus preventing recolonization by the snail hosts. Within this context the invasion of the hydrographic system of Martinique by thiarid snails has resulted in an efficient and sustainable control of the intermediate hosts of schistosomiasis.

  14. Invading freshwater snails and biological control in Martinique Island, French West Indies.

    Science.gov (United States)

    Pointier, J P

    2001-01-01

    Eight alien freshwater snail species were introduced into Martinique Island during the last 50 years. The introduced snails include four planorbids (Biomphalaria straminea, Helisoma duryi, Amerianna carinata and Gyraulus sp.), three thiarids (Melanoides tuberculata, M. amabilis and Tarebia granifera) and one ampullarid (Marisa cornuarietis). Four of these species rapidly colonized the whole Martinican hydrographic system whereas the other four remained restricted to some particular sites. The invasion processes were documented during the last 20 years and showed (i) a rapid invasion of the island by several morphs of M. tuberculata at the beginning of the 80's; (ii) the introduction of T. granifera in 1991 and M. amabilis in 1997; and (iii) the rapid spread of these last two species throughout the island. In the years following its introduction, M. tuberculata was used in biological control experiments against the snail hosts of schistosomiasis, B. glabrata and B. straminea. Experiments were conducted with success in several groups of water-cress beds which constituted the latest transmission sites for schistosomiasis at the beginning of the 80's. A malacological survey carried out in 2000 all over the island showed the absence of B. glabrata but the presence of some residual populations of B. straminea. Long-term studies carried out in Martinique have shown that the thiarids are able to maintain relatively stable populations over a long period of time, thus preventing recolonization by the snail hosts. Within this context the invasion of the hydrographic system of Martinique by thiarid snails has resulted in an efficient and sustainable control of the intermediate hosts of schistosomiasis.

  15. Disease control by chemical and biological fungicides in cultivated mushrooms: button mushroom, oyster mushroom and shiitake

    Directory of Open Access Journals (Sweden)

    Ivana Potočnik

    2015-12-01

    Full Text Available The most commonly cultivated basidiomycetes worldwide and in Serbia are button mushroom (Agaricus bisporus, oyster mushroom (Pleurotus sp. and shiitake (Lentinus edodes. Production of their fruiting bodies is severely afflicted by fungal, bacterial, and viral pathogens that are able to cause diseases which affect yield and quality. Major A. bisporus fungal pathogens include Mycogone perniciosa, Lecanicillium fungicola, and Cladobotryum spp., the causal agents of dry bubble, wet bubble, and cobweb disease, respectively. Various Trichoderma species, the causal agents of green mould, also affect all three kinds of edible mushrooms. Over the past two decades, green mould caused by T. aggressivum has been the most serious disease of button mushroom. Oyster mushroom is susceptible to T. pleurotum and shiitake to T. harzianum. The bacterial brawn blotch disease, caused by Pseudomonas tolaasii, is distributed globally. Disease control on mushroom farms worldwide is commonly based on the use of fungicides. However, evolution of pathogen resistance to fungicides after frequent application, and host sensitivity to fungicides are serious problems. Only a few fungicides are officially recommended in mushroom production: chlorothalonil and thiabendazol in North America and prochloraz in the EU and some other countries. Even though decreased sensitivity levels of L. fungicola and Cladobotryum mycophilum to prochloraz have been detected, disease control is still mainly provided by that chemical fungicide. Considering such resistance evolution, harmful impact to the environment and human health, special attention should be focused on biofungicides, both microbiological products based on Bacillus species and various natural substances of biological origin, together with good programs of hygiene. Introduction of biofungicides has created new possibilities for crop protection with reduced application of chemicals.

  16. Biological soil disinfestation : a safe and effective approach for controlling soilborne pests and diseases

    NARCIS (Netherlands)

    Lamers, J.G.; Wanten, P.J.; Blok, W.J.

    2004-01-01

    Biological soil disinfestation (bsd) is an environmentally friendly method to disinfest the soil from soilborne fungi and nematodes. With biological soil disinfestation a green manure crop (40 tonnes per ha) or other green biomass is homogeneously incorporated into the soil layer that has to be

  17. Biological control reduces growth, and alters water relations of the saltcedar tree (Tamarix spp.) in western Nevada, USA

    Science.gov (United States)

    R.R. Pattison; C.M. D' Antonio; T.L. Dudley

    2011-01-01

    We monitored the impacts of a biological control agent, the saltcedar leaf beetle (Diorhabda carinulata), on the saltcedar tree (Tamarix spp.) at two sites (Humboldt and Walker rivers) in Nevada, USA. At the Humboldt site trees that had experienced three to four defoliation events had more negative water potentials and lower...

  18. Modelling biological control with wild-type and genetically modified baculoviruses in the Helicoverpa armigera-cotton system

    NARCIS (Netherlands)

    Sun, X.; Werf, van der W.; Bianchi, F.J.J.A.; Hu, Z.; Vlak, J.M.

    2006-01-01

    A comprehensive model was developed to simulate virus epizootics in a stage structured insect population and analyse scenarios for the biological control of cotton bollworm (CBW), Helicoverpa armigera, in cotton, using wild-type or genetically modified baculoviruses. In simulations on dosage and

  19. PCR-based identification of the pathogenic bacterium, Acaricomes phytoseiuli, in the biological control agent Phytoseiulus persimilis (Acari: Phytoseiidae)

    NARCIS (Netherlands)

    Gols, R.; Schütte, C.; Stouthamer, R.; Dicke, M.

    2007-01-01

    The predatory mite, Phytoseiulus persimilis is an important biological control agent of herbivorous spider mites. This species is also intensively used in the study of tritrophic effects of plant volatiles in interactions involving plants, herbivores, and their natural enemies. Recently, a novel

  20. Enhancing the effectiveness of biological control programs of invasive species through a more comprehensive pest management approach.

    Science.gov (United States)

    DiTomaso, Joseph M; Van Steenwyk, Robert A; Nowierski, Robert M; Vollmer, Jennifer L; Lane, Eric; Chilton, Earl; Burch, Patrick L; Cowan, Phil E; Zimmerman, Kenneth; Dionigi, Christopher P

    2017-01-01

    Invasive species are one of the greatest economic and ecological threats to agriculture and natural areas in the US and the world. Among the available management tools, biological control provides one of the most economical and long-term effective strategies for managing widespread and damaging invasive species populations of nearly all taxa. However, integrating biological control programs in a more complete integrated pest management approach that utilizes increased information and communication, post-release monitoring, adaptive management practices, long-term stewardship strategies, and new and innovative ecological and genetic technologies can greatly improve the effectiveness of biological control. In addition, expanding partnerships among relevant national, regional, and local agencies, as well as academic scientists and land managers, offers far greater opportunities for long-term success in the suppression of established invasive species. In this paper we direct our recommendations to federal agencies that oversee, fund, conduct research, and develop classical biological control programs for invasive species. By incorporating these recommendations into adaptive management strategies, private and public land managers will have far greater opportunities for long-term success in suppression of established invasive species. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  1. Intrinsic control of rhabdom size and rhodopsin content in the crab compound eye by a circadian biological clock.

    Science.gov (United States)

    Arikawa, K; Morikawa, Y; Suzuki, T; Eguchi, E

    1988-03-15

    Under conditions of constant darkness, rhabdom volume and the amount of visual pigment chromophore show circadian changes in the compound eye of the crab Hemigrapsus sanguineus. The present results indicate that an intrinsic circadian biological clock is involved in the control of the changes.

  2. Contamination delays the release of Laricobius osakensis for biological control of hemlock woolly adelgid: cryptic diversity in Japanese Laricobius spp

    Science.gov (United States)

    Melissa J. Fischer; Nathan P. Havill; Carrie S. Jubb; Sean W. Prosser; Brent D. Opell; Scott M. Salom; Loke T. Kok

    2014-01-01

    Laricobius osakensis (Coleoptera: Derodontidae) was imported from Japan to the United States in 2006 for study in quarantine facilities as a potential biological control of Hemlock Woolly Adelgid. Laricobius osakensis was released from quarantine in 2010, but it was soon discovered that the colony also contained a cryptic species...

  3. Biological and Cultural Control of Olive Fruit Fly in California---Utilization of Parasitoids from USDA-APHIS-PPQ, Guatemala

    Science.gov (United States)

    The parasitoid Psytallia cf. concolor (Szépligeti) was reared on sterile Mediterranean fruit fly larvae at the USDA-APHIS-PPQ, Petapa Quarantine Laboratory in Guatemala and shipped to the USDA-ARS, Parlier, for wide-spread release and biological control of olive fruit fly in California. As many as 3...

  4. Impacts of insect biological control on soil N transformations in Tamarix-invaded ecosystems in the Great Basin

    Science.gov (United States)

    Understanding the impacts of insect biological control of Tamarix spp. on soil nitrogen (N) transformations is important because changes to N supply could alter plant community succession. We investigated short-term and longer-term impacts of herbivory by the northern tamarisk beetle (Diorhabda cari...

  5. Biological control of whitefly on Gerbera: success or failure? : tritrophic interactions between Gerbera jamesonii, Trialeurodes vaporariorum and Encarsia formosa

    NARCIS (Netherlands)

    Sütterlin, S.

    2000-01-01

    In this thesis fundamental and applied research is described that was initiated to develop biological control of whitefly with the parasitoid Encarsia formosa in the ornamental Gerbera jamesonii Hook (Campanulales: Compositae).

    To

  6. 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. Th...

  7. Proceedings of the XIII International Symposium on Biological Control of Weeds; September 11-16, 2011; Waikoloa, Hawaii, USA

    Science.gov (United States)

    Yun Wu; Tracy Johnson; Sharlene Sing; S. Raghu; Greg Wheeler; Paul Pratt; Keith Warner; Ted Center; John Goolsby; Richard Reardon

    2013-01-01

    A total of 208 participants from 78 organizations in 19 countries gathered at the Waikoloa Beach Marriott on the Big Island of Hawaii on September 11-16, 2011 for the XIII International Symposium on Biological Control of Weeds. Following a reception on the first evening, Symposium co-chairs Tracy Johnson and Pat Conant formally welcomed the attendees on the morning of...

  8. Cost-benefit analysis for biological control programs that target insects pests of eucalypts in urban landscapes of California

    Science.gov (United States)

    T.D. Paine; J.G. Millar; L.M. Hanks; J. Gould; Q. Wang; K. Daane; D.L. Dahlsten; E.G. McPherson

    2015-01-01

    As well as being planted for wind breaks, landscape trees, and fuel wood, eucalypts are also widely used as urban street trees in California. They now are besieged by exotic insect herbivores of four different feeding guilds. The objective of the current analysis was to determine the return on investment from biological control programs that have targeted these pests....

  9. Biological control of Trialeurodes vaporariorum by Encarsia formosa on tomato in unheated greenhouses in the high altitude tropics

    NARCIS (Netherlands)

    Vis, de R.M.J.; Lenteren, van J.C.

    2008-01-01

    Biological control of Trialeurodes vaporariorum (Westwood) by Encarsia formosa Gahan was tested during three consecutive production cycles (16-28 weeks) on a beef tomato (Solanum lycopersicum L.) crop in a glasshouse and a plastic greenhouse on the Bogota Plateau in Colombia. During the course of

  10. 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; Lefort, François

    2016-10-06

    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. Copyright © 2016 Crovadore et al.

  11. Progress and challenges of protecting North American ash trees from the emerald ash borer using biological control

    Science.gov (United States)

    Jian Duan; Leah Bauer; Roy van Driesche; Juli. Gould

    2018-01-01

    After emerald ash borer (EAB), Agrilus planipennis Fairmaire, was discovered in the United States, a classical biological control program was initiated against this destructive pest of ash trees (Fraxinus spp.). This biocontrol program began in 2007 after federal regulatory agencies and the state of Michigan approved release of...

  12. Single versus multiple enemies and the impact on biological control of spider mites in cassava fields in West-Africa

    NARCIS (Netherlands)

    Onzo, A.; Sabelis, M.W.; Hanna, R.

    2014-01-01

    To determine whether to use single or multiple predator species for biological pest control requires manipulative field experiments. We performed such tests in Benin (West Africa) in cassava fields infested by the cassava green mite Mononychellus tanajoa, and the cotton red mite Oligonychus

  13. Biological Control of Lettuce Drop and Host Plant Colonization by Rhizospheric and Endophytic Streptomycetes

    Science.gov (United States)

    Chen, Xiaoyulong; Pizzatti, Cristina; Bonaldi, Maria; Saracchi, Marco; Erlacher, Armin; Kunova, Andrea; Berg, Gabriele; Cortesi, Paolo

    2016-01-01

    Lettuce drop, caused by the soil borne pathogen Sclerotinia sclerotiorum, is one of the most common and serious diseases of lettuce worldwide. Increased concerns about the side effects of chemical pesticides have resulted in greater interest in developing biocontrol strategies against S. sclerotiorum. However, relatively little is known about the mechanisms of Streptomyces spp. as biological control agents against S. sclerotiorum on lettuce. Two Streptomyces isolates, S. exfoliatus FT05W and S. cyaneus ZEA17I, inhibit mycelial growth of Sclerotinia sclerotiorum by more than 75% in vitro. We evaluated their biocontrol activity against S. sclerotiorum in vivo, and compared them to Streptomyces lydicus WYEC 108, isolated from Actinovate®. When Streptomyces spp. (106 CFU/mL) were applied to S. sclerotiorum inoculated substrate in a growth chamber 1 week prior lettuce sowing, they significantly reduced the risk of lettuce drop disease, compared to the inoculated control. Interestingly, under field conditions, S. exfoliatus FT05W and S. cyaneus ZEA17I protected lettuce from drop by 40 and 10% respectively, whereas S. lydicus WYEC 108 did not show any protection. We further labeled S. exfoliatus FT05W and S. cyaneus ZEA17I with the enhanced GFP (EGFP) marker to investigate their rhizosphere competence and ability to colonize lettuce roots using confocal laser scanning microscopy (CLSM). The abundant colonization of young lettuce seedlings by both strains demonstrated Streptomyces' capability to interact with the host from early stages of seed germination and root development. Moreover, the two strains were detected also on 2-week-old roots, indicating their potential of long-term interactions with lettuce. Additionally, scanning electron microscopy (SEM) observations showed EGFP-S. exfoliatus FT05W endophytic colonization of lettuce root cortex tissues. Finally, we determined its viability and persistence in the rhizosphere and endorhiza up to 3 weeks by quantifying its

  14. Biological control of lettuce drop and host plant colonization by rhizospheric and endophytic streptomycetes

    Directory of Open Access Journals (Sweden)

    Xiaoyulong eChen

    2016-05-01

    Full Text Available Lettuce drop, caused by the soil borne pathogen Sclerotinia sclerotiorum, is one of the most common and serious diseases of lettuce worldwide. Increased concerns about the side effects of chemical pesticides have resulted in greater interest in developing biocontrol strategies against S. sclerotiorum. However, relatively little is known about the mechanisms of Streptomyces spp. as biological control agents against S. sclerotiorum on lettuce. Two Streptomyces isolates, S. exfoliatus FT05W and S. cyaneus ZEA17I, inhibit mycelial growth of Sclerotinia sclerotiorum by more than 75% in vitro. We evaluated their biocontrol activity against S. sclerotiorum in vivo, and compared them to Streptomyces lydicus WYEC 108, isolated from Actinovate®. When Streptomyces spp. (106 CFU/mL were applied to S. sclerotiorum inoculated substrate in a growth chamber one week prior lettuce sowing, they significantly reduced the risk of lettuce drop disease, compared to the inoculated control. Interestingly, under field conditions, S. exfoliatus FT05W and S. cyaneus ZEA17I protected lettuce from drop by 40% and 10% respectively, whereas S. lydicus WYEC 108 did not show any protection. We further labeled S. exfoliatus FT05W and S. cyaneus ZEA17I with the enhanced GFP (EGFP marker to investigate their rhizosphere competence and ability to colonize lettuce roots using confocal laser scanning microscopy (CLSM. The abundant colonization of young lettuce seedlings by both strains demonstrated Streptomyces’ capability to interact with the host from early stages of seed germination and root development. Moreover, the two strains were detected also on two-week-old roots, indicating their potential of long-term interactions with lettuce. Additionally, scanning electron microscopy (SEM observations showed EGFP-S. exfoliatus FT05W endophytic colonization of lettuce root cortex tissues. Finally, we determined its viability and persistence in the rhizosphere and endorhiza up to

  15. Therapist adherence in the strong without anorexia nervosa (SWAN) study: A randomized controlled trial of three treatments for adults with anorexia nervosa.

    Science.gov (United States)

    Andony, Louise J; Tay, Elaine; Allen, Karina L; Wade, Tracey D; Hay, Phillipa; Touyz, Stephen; McIntosh, Virginia V W; Treasure, Janet; Schmidt, Ulrike H; Fairburn, Christopher G; Erceg-Hurn, David M; Fursland, Anthea; Crosby, Ross D; Byrne, Susan M

    2015-12-01

    To develop a psychotherapy rating scale to measure therapist adherence in the Strong Without Anorexia Nervosa (SWAN) study, a multi-center randomized controlled trial comparing three different psychological treatments for adults with anorexia nervosa. The three treatments under investigation were Enhanced Cognitive Behavioural Therapy (CBT-E), the Maudsley Anorexia Nervosa Treatment for Adults (MANTRA), and Specialist Supportive Clinical Management (SSCM). The SWAN Psychotherapy Rating Scale (SWAN-PRS) was developed, after consultation with the developers of the treatments, and refined. Using the SWAN-PRS, two independent raters initially rated 48 audiotapes of treatment sessions to yield inter-rater reliability data. One rater proceeded to rate a total of 98 audiotapes from 64 trial participants. The SWAN-PRS demonstrated sound psychometric properties, and was considered a reliable measure of therapist adherence. The three treatments were highly distinguishable by independent raters, with therapists demonstrating significantly more behaviors consistent with the actual allocated treatment compared to the other two treatment modalities. There were no significant site differences in therapist adherence observed. The findings provide support for the internal validity of the SWAN study. The SWAN-PRS was deemed suitable for use in other trials involving CBT-E, MANTRA, or SSCM. The Authors. International Journal of Eating Disorders Published by Wiley Periodicals, Inc.

  16. Is synthetic biology mechanical biology?

    Science.gov (United States)

    Holm, Sune

    2015-12-01

    A widespread and influential characterization of synthetic biology emphasizes that synthetic biology is the application of engineering principles to living systems. Furthermore, there is a strong tendency to express the engineering approach to organisms in terms of what seems to be an ontological claim: organisms are machines. In the paper I investigate the ontological and heuristic significance of the machine analogy in synthetic biology. I argue that the use of the machine analogy and the aim of producing rationally designed organisms does not necessarily imply a commitment to mechanical biology. The ideal of applying engineering principles to biology is best understood as expressing recognition of the machine-unlikeness of natural organisms and the limits of human cognition. The paper suggests an interpretation of the identification of organisms with machines in synthetic biology according to which it expresses a strategy for representing, understanding, and constructing living systems that are more machine-like than natural organisms.

  17. Biological Control of Fusarium Stalk Rot of Maize Using Bacillus spp

    Directory of Open Access Journals (Sweden)

    Joon-Hee Han

    2015-12-01

    Full Text Available Maize (Zea mays L. is an economically important crop in worldwide. While the consumption of the maize is steadily increasing, the yield is decreasing due to continuous mono-cultivation and infection of soil-borne fungal pathogens such as Fusarium species. Recently, stalk rot disease in maize, caused by F. subglutinans and F. temperatum has been reported in Korea. In this study, we isolated bacterial isolates in rhizosphere soil of maize and subsequently tested for antagonistic activities against F. subglutinans and F. temperatum. A total of 1,357 bacterial strains were isolated from rhizosphere. Among them three bacterial isolates (GC02, GC07, GC08 were selected, based on antagonistic effects against Fusarium species. The isolates GC02 and GC07 were most efficient in inhibiting the mycelium growth of the pathogens. The three isolates GC02, GC07 and GC08 were identified as Bacillus methylotrophicus, B. amyloliquefaciens and B. thuringiensis using 16S rRNA sequence analysis, respectively. GC02 and GC07 bacterial suspensions were able to suppress over 80% conidial germination of the pathogens. GC02, GC07 and GC08 were capable of producing large quantities of protease enzymes, whereas the isolates GC07 and GC08 produced cellulase enzymes. The isolates GC02 and GC07 were more efficient in phosphate solubilization and siderophore production than GC08. Analysis of disease suppression revealed that GC07 was most effective in suppressing the disease development of stalk rot. It was also found that B. methylotrophicus GC02 and B. amyloliquefaciens GC07 have an ability to inhibit the growth of other plant pathogenic fungi. This study indicated B. methylotrophicus GC02 and B. amyloliquefaciens GC07 has potential for being used for the development of a biological control agent.

  18. Optimal Plant Carbon Allocation Implies a Biological Control on Nitrogen Availability

    Science.gov (United States)

    Prentice, I. C.; Stocker, B. D.

    2015-12-01

    The degree to which nitrogen availability limits the terrestrial C sink under rising CO2 is a key uncertainty in carbon cycle and climate change projections. Results from ecosystem manipulation studies and meta-analyses suggest that plant C allocation to roots adjusts dynamically under varying degrees of nitrogen availability and other soil fertility parameters. In addition, the ratio of biomass production to GPP appears to decline under nutrient scarcity. This reflects increasing plant C exudation into the soil (Cex) with decreasing nutrient availability. Cex is consumed by an array of soil organisms and may imply an improvement of nutrient availability to the plant. Thus, N availability is under biological control, but incurs a C cost. In spite of clear observational support, this concept is left unaccounted for in Earth system models. We develop a model for the coupled cycles of C and N in terrestrial ecosystems to explore optimal plant C allocation under rising CO2 and its implications for the ecosystem C balance. The model follows a balanced growth approach, accounting for the trade-offs between leaf versus root growth and Cex in balancing C fixation and N uptake. We assume that Cex is proportional to root mass, and that the ratio of N uptake (Nup) to Cex is proportional to inorganic N concentration in the soil solution. We further assume that Cex is consumed by N2-fixing processes if the ratio of Nup:Cex falls below the inverse of the C cost of N2-fixation. Our analysis thereby accounts for the feedbacks between ecosystem C and N cycling and stoichiometry. We address the question of how the plant C economy will adjust under rising atmospheric CO2 and what this implies for the ecosystem C balance and the degree of N limitation.

  19. Physical and biological controls over patterns of methane flux from wetland soils

    Science.gov (United States)

    Owens, S. M.; von Fischer, J. C.

    2006-12-01

    While methane (CH4) production and plant-facilitated gas transport both contribute to patterns of CH4 emissions from wetlands, the relative importance of each mechanism is uncertain. In flooded wetland soils, CH4 is produced by anaerobic methanogenic bacteria. In the absence of competing oxidizers (i.e. SO42-, NO3-, O2), CH4 production is limited by the availability of labile carbon, which is supplied from recent plant primary production (e.g. as root exudates) and converted by anaerobic fermenting bacteria into methanogenic substrate (e.g. acetate). Because diffusion of gases through saturated soils is extremely slow, the aerenchymous tissues of wetland plants provide the primary pathway for CH4 emissions in systems dominated by emergent vascular vegetation. Aerenchyma also function to shuttle atmospheric oxygen to belowground plant tissues for respiration. Consequentially, root radial oxygen loss results in an oxidized rhizosphere, which limits CH4 production and provides habitat for aerobic methanotrophic bacteria, potentially reducing CH4 emissions. To test the contribution of recent photosynthates on CH4 emissions, a shading experiment was conducted in a Juncus-dominated wetland in the Colorado Front Range. Shade treatments significantly reduced net ecosystem production (NEE) and gross primary production (GPP) compared to control plots (p=0.0194 and p=0.0551, respectively). While CH4 emissions did not significantly differ between treatments, CH4 flux rates were strongly correlated with NEE (p=0.0063) and GPP (p=0.0020), in support of the hypothesis that labile carbon from recent photosynthesis controls patterns of CH4 emissions. The relative importance of plant gas transport and methane consumption rates on CH4 emissions is not known. Methane flux is more tightly correlated with NEE than GPP, which may be explained by increased CH4 consumption or decreased CH4 production as a result of rhizospheric oxidation. The ability to predict future emissions of this

  20. Understanding the electric field control of the electronic and optical properties of strongly-coupled multi-layered quantum dot molecules.

    Science.gov (United States)

    Usman, Muhammad

    2015-10-21

    Strongly-coupled quantum dot molecules (QDMs) are widely employed in the design of a variety of optoelectronic, photovoltaic, and quantum information devices. An efficient and optimized performance of these devices demands engineering of the electronic and optical properties of the underlying QDMs. The application of electric fields offers a way to realise such a control over the QDM characteristics for a desired device operation. We performed multi-million-atom atomistic tight-binding calculations to study the influence of electric fields on the electron and hole wave function confinements and symmetries, the ground-state transition energies, the band-gap wavelengths, and the optical transition modes. Electrical fields parallel (Ep) and anti-parallel (Ea) to the growth direction were investigated to provide a comprehensive guide for understanding the electric field effects. The strain-induced asymmetry of the hybridized electron states is found to be weak and can be balanced by applying a small Ea electric field, of the order of 1 kV cm(-1). The strong interdot couplings completely break down at large electric fields, leading to single QD states confined at the opposite edges of the QDM. This mimics a transformation from a type-I band structure to a type-II band structure for the QDMs, which is a critical requirement for the design of intermediate-band solar cells (IBSCs). The analysis of the field-dependent ground-state transition energies reveals that the QDM can be operated both as a high dipole moment device by applying large electric fields and as a high polarizability device under the application of small electric field magnitudes. The quantum confined Stark effect (QCSE) red shifts the band-gap wavelength to 1.3 μm at the 15 kV cm(-1) electric field; however the reduced electron-hole wave function overlaps lead to a decrease in the interband optical transition strengths by roughly three orders of magnitude. The study of the polarisation-resolved optical