WorldWideScience

Sample records for strongest biocidal action

  1. Towards a more realistic picture of in situ biocide actions: Combining physiological and microscopy techniques

    Energy Technology Data Exchange (ETDEWEB)

    Speranza, M., E-mail: speranzamariela@gmail.com [Museo Nacional de Ciencias Naturales, MNCN-CSIC, Serrano 115 bis, 28006 Madrid (Spain); Wierzchos, J.; De Los Rios, A.; Perez-Ortega, S. [Museo Nacional de Ciencias Naturales, MNCN-CSIC, Serrano 115 bis, 28006 Madrid (Spain); Souza-Egipsy, V. [Instituto de Ciencias Agrarias, ICA-CSIC, Serrano 115 bis, 28006 Madrid (Spain); Ascaso, C., E-mail: ascaso@mncn.csic.es [Museo Nacional de Ciencias Naturales, MNCN-CSIC, Serrano 115 bis, 28006 Madrid (Spain)

    2012-11-15

    In this study, we combined chlorophyll a fluorescence (ChlaF) measurements, using pulse-amplitude-modulate (PAM) equipment, with scanning electron microscopy in backscattered electron mode (SEM-BSE) and transmission electron microscopy (TEM) images to evaluate the actions of Koretrel at lower concentrations on Verrucaria nigrescens colonising a dolostone. ChlaF measurements are good indicators of the damaging effects of biocides. However, these indicators only provide an incomplete view of the mechanism of biocides used to control biodeterioration agents. The death of the V. nigrescens photobiont at two biocide concentrations was revealed by PAM, SEM-BSE and TEM. Once Koretrel was applied, the Fv/Fm ratios markedly fell in the first few hours after the 1.5% treatment, and ratios for the 3% dilution remained close to zero throughout the study. The algal zone shows the plasmolysed appearance of the photobiont cells, and important aspects related to the action of the biocide on free and lichenised fungi were also detected using SEM-BSE. Many of the mycobiont cells had only their cell walls preserved; although, some fungal hyphae in lichen thalli and some microorganisms in endolithic clusters maintained lipid storage in their cytoplasm. These results indicated that the combination of physiological and microscopy techniques improves the assessment of biocide action in situ and this will help to optimize protocols in order to reduce the emission of these compounds to the environment. -- Highlights: Black-Right-Pointing-Pointer We combined ChlaF measurements with EM images to analyses the biocides action on stone biodeterioration agents. Black-Right-Pointing-Pointer At lower biocide concentrations damage to photobiont and mycobiont cells integrity, ultrastructure and vitality were observed. Black-Right-Pointing-Pointer The limited action of biocides on fungi and algae were detected using SEM-BSE. Black-Right-Pointing-Pointer The combination of physiological and microscopy

  2. Biofilms of a Bacillus subtilis hospital isolate protect Staphylococcus aureus from biocide action.

    Directory of Open Access Journals (Sweden)

    Arnaud Bridier

    Full Text Available The development of a biofilm constitutes a survival strategy by providing bacteria a protective environment safe from stresses such as microbicide action and can thus lead to important health-care problems. In this study, biofilm resistance of a Bacillus subtilis strain (called hereafter ND(medical recently isolated from endoscope washer-disinfectors to peracetic acid was investigated and its ability to protect the pathogen Staphylococcus aureus in mixed biofilms was evaluated. Biocide action within Bacillus subtilis biofilms was visualised in real time using a non-invasive 4D confocal imaging method. The resistance of single species and mixed biofilms to peracetic acid was quantified using standard plate counting methods and their architecture was explored using confocal imaging and electronic microscopy. The results showed that the ND(medical strain demonstrates the ability to make very large amount of biofilm together with hyper-resistance to the concentration of PAA used in many formulations (3500 ppm. Evidences strongly suggest that the enhanced resistance of the ND(medical strain was related to the specific three-dimensional structure of the biofilm and the large amount of the extracellular matrix produced which can hinder the penetration of peracetic acid. When grown in mixed biofilm with Staphylococcus aureus, the ND(medical strain demonstrated the ability to protect the pathogen from PAA action, thus enabling its persistence in the environment. This work points out the ability of bacteria to adapt to an extremely hostile environment, and the necessity of considering multi-organism ecosystems instead of single species model to decipher the mechanisms of biofilm resistance to antimicrobials agents.

  3. Biocidal action of ozone-treated polystyrene surfaces on vegetative and sporulated bacteria

    International Nuclear Information System (INIS)

    Mahfoudh, Ahlem; Barbeau, Jean; Moisan, Michel; Leduc, Annie; Seguin, Jacynthe

    2010-01-01

    Surfaces of materials can be modified to ensure specific interaction features with microorganisms. The current work discloses biocidal properties of polystyrene (PS) Petri-dish surfaces that have been exposed to a dry gaseous-ozone flow. Such treated PS surfaces are able to inactivate various species of vegetative and sporulated bacteria on a relatively short contact time. Denaturation of proteins seems likely based on a significant loss of enzymatic activity of the lysozyme protein. Characterization of these surfaces by atomic-force microscopy (AFM), Fourier-transform infra-red (FTIR) spectroscopy and X-ray photoelectron spectroscopy (XPS) reveals specific structural and chemical modifications as compared to untreated PS. Persistence of the biocidal properties of these treated surfaces is observed. This ozone-induced process is technically simple to achieve and does not require active precursors as in grafting.

  4. Resistance of Bacteria to Biocides.

    Science.gov (United States)

    Maillard, Jean-Yves

    2018-04-01

    Biocides and formulated biocides are used worldwide for an increasing number of applications despite tightening regulations in Europe and in the United States. One concern is that such intense usage of biocides could lead to increased bacterial resistance to a product and cross-resistance to unrelated antimicrobials including chemotherapeutic antibiotics. Evidence to justify such a concern comes mostly from the use of health care-relevant bacterial isolates, although the number of studies of the resistance characteristics of veterinary isolates to biocides have increased the past few years. One problem remains the definition of "resistance" and how to measure resistance to a biocide. This has yet to be addressed globally, although the measurement of resistance is becoming more pressing, with regulators both in Europe and in the United States demanding that manufacturers provide evidence that their biocidal products will not impact on bacterial resistance. Alongside in vitro evidence of potential antimicrobial cross-resistance following biocide exposure, our understanding of the mechanisms of bacterial resistance and, more recently, our understanding of the effect of biocides to induce a mechanism(s) of resistance in bacteria has improved. This article aims to provide an understanding of the development of antimicrobial resistance in bacteria following a biocide exposure. The sections provide evidence of the occurrence of bacterial resistance and its mechanisms of action and debate how to measure bacterial resistance to biocides. Examples pertinent to the veterinary field are used where appropriate.

  5. Does limited virucidal activity of biocides include duck hepatitis B virucidal action?

    Directory of Open Access Journals (Sweden)

    Sauerbrei Andreas

    2012-10-01

    Full Text Available Abstract Background There is agreement that the infectivity assay with the duck hepatitis B virus (DHBV is a suitable surrogate test to validate disinfectants for hepatitis B virucidal activity. However, since this test is not widely used, information is necessary whether disinfectants with limited virucidal activity also inactivate DHBV. In general, disinfectants with limited virucidal activity are used for skin and sensitive surfaces while agents with full activity are more aggressive. The present study compares the activity of five different biocides against DHBV and the classical test virus for limited virucidal activity, the vaccinia virus strain Lister Elstree (VACV or the modified vaccinia Ankara strain (MVA. Methods Virucidal assay was performed as suspension test according to the German DVV/RKI guideline. Duck hepatitis B virus obtained from congenitally infected Peking ducks was propagated in primary duck embryonic hepatocytes and was detected by indirect immunofluorescent antigen staining. Results The DHBV was inactivated by the use of 40% ethanol within 1-min and 30% isopropanol within 2-min exposure. In comparison, 40% ethanol within 2-min and 40% isopropanol within 1-min exposure were effective against VACV/MVA. These alcohols only have limited virucidal activity, while the following agents have full activity. 0.01% peracetic acid inactivated DHBV within 2 min and a concentration of 0.005% had virucidal efficacy against VACV/MVA within 1 min. After 2-min exposure, 0.05% glutardialdehyde showed a comparable activity against DHBV and VACV/MVA. This is also the case for 0.7% formaldehyde after a contact time of 30 min. Conclusions Duck hepatitis B virus is at least as sensitive to limited virucidal activity as VACV/MVA. Peracetic acid is less effective against DHBV, while the alcohols are less effective against VACV/MVA. It can be expected that in absence of more direct tests the results may be extrapolated to HBV.

  6. Combined biocidal action of silver nanoparticles and ions against Chlorococcales (Scenedesmus quadricauda, Chlorella vulgaris) and filamentous algae (Klebsormidium sp.).

    Science.gov (United States)

    Zouzelka, Radek; Cihakova, Pavlina; Rihova Ambrozova, Jana; Rathousky, Jiri

    2016-05-01

    Despite the extensive research, the mechanism of the antimicrobial and biocidal performance of silver nanoparticles has not been unequivocally elucidated yet. Our study was aimed at the investigation of the ability of silver nanoparticles to suppress the growth of three types of algae colonizing the wetted surfaces or submerged objects and the mechanism of their action. Silver nanoparticles exhibited a substantial toxicity towards Chlorococcales Scenedesmus quadricauda, Chlorella vulgaris, and filamentous algae Klebsormidium sp., which correlated with their particle size. The particles had very good stability against agglomeration even in the presence of multivalent cations. The concentration of silver ions in equilibrium with nanoparticles markedly depended on the particle size, achieving about 6 % and as low as about 0.1 % or even less for the particles 5 nm in size and for larger ones (40-70 nm), respectively. Even very limited proportion of small particles together with larger ones could substantially increase concentration of Ag ions in solution. The highest toxicity was found for the 5-nm-sized particles, being the smallest ones in this study. Their toxicity was even higher than that of silver ions at the same silver concentration. When compared as a function of the Ag(+) concentration in equilibrium with 5-nm particles, the toxicity of ions was at least 17 times higher than that obtained by dissolving silver nitrite (if not taking into account the effect of nanoparticles themselves). The mechanism of the toxicity of silver nanoparticles was found complex with an important role played by the adsorption of silver nanoparticles and the ions released from the particles on the cell surface. This mechanism could be described as some sort of synergy between nanoparticles and ions. While our study clearly showed the presence of this synergy, its detailed explanation is experimentally highly demanding, requiring a close cooperation between materials scientists

  7. Priorities for action on the social determinants of health: Empirical evidence on the strongest associations with life expectancy in 54 low-income countries, 1990-2012.

    Science.gov (United States)

    Hauck, K; Martin, S; Smith, P C

    2016-10-01

    The WHO Commission on the Social Determinants of Health set out an impressive collection of policy proposals on the social determinants of health. However, a serious weakness for securing implementation is the difficulty for policymakers in identifying priorities for action. The objective of this study is to determine a small set of the most influential determinants using existing data and an empirical approach. 45 Indicators from the World Bank's World Development Indicators are selected to measure attainment for the determinants proposed by the Commission. Panel data models of life expectancy at birth for 54 low-income countries over the years 1990-2012 (1188 country-years) are estimated. Each determinant is subjected to a robustness test using Extreme Bound Analysis, to determine the stability of its estimated impact on life expectancy. For 20 robust and significant determinants the magnitude of association with life expectancy is determined. The largest average increases in life expectancy at 14.5 months per capita is associated with a one standard deviation reduction in HIV prevalence among children, followed by advances in gender equality at 9.4 months. Improvements in life expectancy between 6 and 9 months are associated with agricultural production, political stability, access to clean water and sanitation, good governance, and primary school enrolment. Improvements below 6 months are associated with increases in private health expenditure and overseas development assistance, and control of armed conflict and HIV prevalence among men. There is no evidence that national income, public spending on healthcare and education, secondary schooling, terms of international trade, employment, debt service and relief, out-of-pocket expenditures, agricultural ex- or imports, lifestock production, foreign investment, urbanization or environmental degradation are robustly associated with population health. Results provide support for the relevance of some proposed

  8. Ecotoxicological potential of the biocides terbutryn, octhilinone and methylisothiazolinone: Underestimated risk from biocidal pathways?

    Science.gov (United States)

    Kresmann, Simon; Arokia, Arokia Hansel Rajan; Koch, Christoph; Sures, Bernd

    2018-06-01

    The use of biocides by industry, agriculture and households increased throughout the last two decades. Many new applications with known substances enriched the variety of biocidal pollution sources for the aquatic environment. While agriculture was the major source for a long time, leaching from building facades and preservation of personal care and cleaning products was identified as new sources in the last few years. With the different usage forms of biocidal products the complexity of legislative regulation increased as well. The requirements for risk assessment differ from one law to another and the potential risk of substances under different regulations might be underestimated. Still EC 50 and predicted no-effect concentration (PNEC) values gained from testing with different species are the core of environmental risk assessment, but ecotoxicological data is limited or lacking for many biocides. In this study the biocides widely used in facade coatings and household products terbutryn, octhilinone and methylisothiazolinone were tested with the Daphnia magna acute immobilisation assay, the neutral red uptake assay and the ethoxyresorufin-O-deethylase (EROD) assay, performed with rainbow trout liver (RTL-W1) cells. Further, the MTT assay with the ovarian cell line CHO-9 from Chinese hamster was used as mammalian model. Octhilinone induced the strongest effects with EC 50 values of 156μg/l in the D. magna assay, while terbutryn showed the weakest effects with 8390μg/l and methylisothiazolinone 513μg/l respectively. All other assays showed higher EC 50 values and thus only weak effects. EROD assays did not show any effects. With additional literature and database records PNEC values were calculated: terbutryn reached 0.003μg/l, octhilinone 0.05μg/l and methylisothiazolinone 0.5μg/l. Potential ecotoxicological risks of these biocides are discussed, considering environmental concentrations. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. Articles Treated with Biocidal Products

    OpenAIRE

    Söyleriz, Yüksel

    2015-01-01

    In this study, articles treated with biocidal products have been assessed in the scope of Directive 98/8/EC Concerning the Placing of Biocidal Products on the Market and of Regulation (EU) No 528/2012 concerning the Making Available on the Market and Use of Biocidal Products.

  10. Biocide Runoff from Building Facades

    DEFF Research Database (Denmark)

    Bollmann, Ulla E.; Fernández-Calviño, David; Brandt, Kristian K.

    2017-01-01

    Biocides are common additives in building materials. In-can and film preservatives in polymer-resin render and paint, as well as wood preservatives are used to protect facade materials from microbial spoilage. Biocides leach from the facade material with driving rain, leading to highly polluted...

  11. Biocide patch tests

    DEFF Research Database (Denmark)

    Andersen, Klaus Ejner; Veien, Niels

    1985-01-01

    Routine patch testing with a series of 6 industrial biocides containing methylene-bis-thiocyanate (Cytox 3522), benzisothiazolin-3-one (BIT), chlorocresol (Preventol CMK), 2-n-octyl-4-isothiazolin-3-one (Kathon 893), polyhydroxymethylene monobenzylether (Preventol D2) or 1,3,5-tris (hydroxy......-ethyl) hexahydrotriazine (Grotan BK) was carried out in 6 Danish out-patient clinics to evaluate guinea pig allergy test results with the same compounds. A total of 1652 consecutive patients with dermatitis were tested. The usefulness of this patch test battery was limited. There were a few positive reactions to Cytox...... of male patients and atopics, but significant differences in the frequencies of occupational cases, hand eczemas, and leg ulcers/stasis dermatitis, indicating possible variations in referral patterns, use of patch tests, and/or environmental factors....

  12. New biocides for antifouling paints

    International Nuclear Information System (INIS)

    Mazziotti, Isabella; Massanisso, Paolo; Cremisini, Carlo; Chiavarini, Salvatore; Fantini, Michele; Morabito, Roberto

    2005-01-01

    The antifouling paints are used for protecting the hulls of the boasts from the undesirable accumulation of micro-organisms, plants, and animals on artificial surfaces (marine biological fouling). These paints constitute a potential risk for the marine environment, because of the presence in their formulation, among the other potentially toxic components, of organic compounds acting as biocide. The environmental problems associated with the use of the organotin compounds as biocides in the antifouling paints, have lead to the international ban of these compounds. In the article the new antifouling paints coming up the national and international market are shortly introduced and discussed, with particular attention respect to the new organic compounds used as biocides. In Italy quite a few marine monitoring campaigns have been carried out for organotin compounds, on the contrary there is a lack of data regarding the presence of other biocides [it

  13. Biocidal products: endorsement procedure for placing on the market

    Directory of Open Access Journals (Sweden)

    Mihaela Scripcariu,

    2010-06-01

    Full Text Available Biocidal products are active substances and preparations containing one or more active substances, putin a form that is supplied to the user, with aim to destroy, to prevent the action or to exercise control over adifferent effect any harmful organism by chemical or biological means.By definition, these products are susceptible to have harmful effects on humans, animals and theenvironment as the main objective of European legislative regulations in this area is to ensure the highestlevel protection by restricting the placing on the market and use only those biocidal products which have anacceptable risk of danger to humans or the environment.The favourable opinion for the placing on the market is made after the evaluation of technicaldocumentation of biocidal products, completed by preparing a report of assessment with the formulation of theproposal to issue notice for placing on the market by the National Commission of Biocidal Products.ICBMV is designated as an authority competent to assess technical documentations on efficacy,chemistry and toxicity data of biocidal products, product type 3: Veterinary hygiene products.

  14. Silver-enhanced block copolymer membranes with biocidal activity

    KAUST Repository

    Madhavan, Poornima

    2014-11-12

    Silver nanoparticles were deposited on the surface and pore walls of block copolymer membranes with highly ordered pore structure. Pyridine blocks constitute the pore surfaces, complexing silver ions and promoting a homogeneous distribution. Nanoparticles were then formed by reduction with sodium borohydride. The morphology varied with the preparation conditions (pH and silver ion concentration), as confirmed by field emission scanning and transmission electron microscopy. Silver has a strong biocide activity, which for membranes can bring the advantage of minimizing the growth of bacteria and formation of biofilm. The membranes with nanoparticles prepared under different pH values and ion concentrations were incubated with Pseudomonas aeruginosa and compared with the control. The strongest biocidal activity was achieved with membranes containing membranes prepared under pH 9. Under these conditions, the best distribution with small particle size was observed by microscopy.

  15. Silver-enhanced block copolymer membranes with biocidal activity

    KAUST Repository

    Madhavan, Poornima; Hong, Pei-Ying; Sougrat, Rachid; Nunes, Suzana Pereira

    2014-01-01

    Silver nanoparticles were deposited on the surface and pore walls of block copolymer membranes with highly ordered pore structure. Pyridine blocks constitute the pore surfaces, complexing silver ions and promoting a homogeneous distribution. Nanoparticles were then formed by reduction with sodium borohydride. The morphology varied with the preparation conditions (pH and silver ion concentration), as confirmed by field emission scanning and transmission electron microscopy. Silver has a strong biocide activity, which for membranes can bring the advantage of minimizing the growth of bacteria and formation of biofilm. The membranes with nanoparticles prepared under different pH values and ion concentrations were incubated with Pseudomonas aeruginosa and compared with the control. The strongest biocidal activity was achieved with membranes containing membranes prepared under pH 9. Under these conditions, the best distribution with small particle size was observed by microscopy.

  16. The strongest magnetic fields in the universe

    CERN Document Server

    Balogh, A; Falanga, M; Lyutikov, M; Mereghetti, S; Piran, T; Treumann, RA

    2016-01-01

    This volume extends the ISSI series on magnetic fields in the Universe into the domain of what are by far the strongest fields in the Universe, and stronger than any field that could be produced on Earth. The chapters describe the magnetic fields in non-degenerate strongly magnetized stars, degenerate stars (such as white dwarfs and neutron stars), exotic members called magnetars, and in their environments, as well as magnetic fields in the environments of black holes. These strong fields have a profound effect on the behavior of matter, visible in particular in highly variable processes like radiation in all known wavelengths, including Gamma-Ray bursts. The generation and structure of such strong magnetic fields and effects on the environment are also described.

  17. The biocides market for nano actives

    DEFF Research Database (Denmark)

    Hansen, Steffen Foss; Brinch, Anna

    2014-01-01

    Information is emerging on which nanomaterials might be used in biocides, but new test methods are needed.......Information is emerging on which nanomaterials might be used in biocides, but new test methods are needed....

  18. The Strongest Magnetic Field in Sunspots

    Science.gov (United States)

    Okamoto, J.; Sakurai, T.

    2017-12-01

    Sunspots are concentrations of magnetic fields on the solar surface. Generally, the strongest magnetic field in each sunspot is located in the dark umbra in most cases. A typical field strength in sunspots is around 3,000 G. On the other hand, some exceptions also have been found in complex sunspots with bright regions such as light bridges that separate opposite polarity umbrae, for instance with a strength of 4,300 G. However, the formation mechanism of such strong fields outside umbrae is still puzzling. Here we report an extremely strong magnetic field in a sunspot, which was located in a bright region sandwiched by two opposite-polarity umbrae. The strength is 6,250 G, which is the largest ever observed since the discovery of magnetic field on the Sun in 1908 by Hale. We obtained 31 scanned maps of the active region observed by Hinode/SOT/SP with a cadence of 3 hours over 5 days (February 1-6, 2014). Considering the spatial and temporal evolution of the vector magnetic field and the Doppler velocity in the bright region, we suggested that this strong field region was generated as a result of compression of one umbra pushed by the outward flow from the other umbra (Evershed flow), like the subduction of the Earth's crust in plate tectonics.

  19. Biocide Usage in Plastic Products

    OpenAIRE

    Kavak, Nergizhan; Çakır, Ayşegül; Koltuk, Fatmagül; Uzun, Utku

    2015-01-01

    People’s demand of improving their life quality caused to the term of hygiene become popular and increased the tendency to use more reliable and healthy products. This tendency makes the continuous developments in the properties of the materials used in manufactured goods compulsory. It is possible to create anti-bacterial plastic products by adding biocidal additives to plastic materials which have a wide-range of application in the areas such as health (medicine), food and many other indust...

  20. Biocidal Products and Borderline Products

    OpenAIRE

    Yılmaz, Abdullah

    2015-01-01

    Biocidal product is defined as preparations sold in ready form to use that contains one or more active substances and has control effect, movement restriction or destruction against harmful organisms which has harmful effect on products that people use or produce or animals or environment. These substances which are composed mostly chemicals and ease our lifes are used in increasingly every areas of our life on the other hand they carry variety of risks and threaten our lives. In terms of env...

  1. Toxicity Tests Applied to the Biocidal Products

    OpenAIRE

    Karabay Yavaşoğlu, N.Ülkü

    2015-01-01

    Biocides are defined as chemical substances used to suppress, destroy, deter, render harmless, or exert a controlling effect on any harmful organism to human or animal health, or that cause damage to natural or manufactured materials. Biocidal products (BPs) containing biocides are disinfectants, products related to human and veterinary hygiene, products used for pests such as insects, rodents etc., repellents and industrial chemicals like anti-fouling paints for ship and material preservativ...

  2. Risks of Using Antifouling Biocides in Aquaculture

    Directory of Open Access Journals (Sweden)

    José Meseguer

    2012-02-01

    Full Text Available Biocides are chemical substances that can deter or kill the microorganisms responsible for biofouling. The rapid expansion of the aquaculture industry is having a significant impact on the marine ecosystems. As the industry expands, it requires the use of more drugs, disinfectants and antifoulant compounds (biocides to eliminate the microorganisms in the aquaculture facilities. The use of biocides in the aquatic environment, however, has proved to be harmful as it has toxic effects on the marine environment. Organic booster biocides were recently introduced as alternatives to the organotin compounds found in antifouling products after restrictions were imposed on the use of tributyltin (TBT. The replacement products are generally based on copper metal oxides and organic biocides. The biocides that are most commonly used in antifouling paints include chlorothalonil, dichlofluanid, DCOIT (4,5-dichloro-2-n-octyl-4-isothiazolin-3-one, Sea-nine 211®, Diuron, Irgarol 1051, TCMS pyridine (2,3,3,6-tetrachloro-4-methylsulfonyl pyridine, zinc pyrithione and Zineb. There are two types of risks associated with the use of biocides in aquaculture: (i predators and humans may ingest the fish and shellfish that have accumulated in these contaminants and (ii the development of antibiotic resistance in bacteria. This paper provides an overview of the effects of antifouling (AF biocides on aquatic organisms. It also provides some insights into the effects and risks of these compounds on non-target organisms.

  3. Risks of Using Antifouling Biocides in Aquaculture

    Science.gov (United States)

    Guardiola, Francisco Antonio; Cuesta, Alberto; Meseguer, José; Esteban, Maria Angeles

    2012-01-01

    Biocides are chemical substances that can deter or kill the microorganisms responsible for biofouling. The rapid expansion of the aquaculture industry is having a significant impact on the marine ecosystems. As the industry expands, it requires the use of more drugs, disinfectants and antifoulant compounds (biocides) to eliminate the microorganisms in the aquaculture facilities. The use of biocides in the aquatic environment, however, has proved to be harmful as it has toxic effects on the marine environment. Organic booster biocides were recently introduced as alternatives to the organotin compounds found in antifouling products after restrictions were imposed on the use of tributyltin (TBT). The replacement products are generally based on copper metal oxides and organic biocides. The biocides that are most commonly used in antifouling paints include chlorothalonil, dichlofluanid, DCOIT (4,5-dichloro-2-n-octyl-4-isothiazolin-3-one, Sea-nine 211®), Diuron, Irgarol 1051, TCMS pyridine (2,3,3,6-tetrachloro-4-methylsulfonyl pyridine), zinc pyrithione and Zineb. There are two types of risks associated with the use of biocides in aquaculture: (i) predators and humans may ingest the fish and shellfish that have accumulated in these contaminants and (ii) the development of antibiotic resistance in bacteria. This paper provides an overview of the effects of antifouling (AF) biocides on aquatic organisms. It also provides some insights into the effects and risks of these compounds on non-target organisms. PMID:22408407

  4. Modelling biocide release based on coating properties

    NARCIS (Netherlands)

    Erich, S.J.F.; Baukh, V.

    2016-01-01

    Growth of micro-organisms on coated substrates is a common problem, since it reduces the performance of materials, in terms of durability as well as aesthetics. In order to prevent microbial growth biocides are frequently added to coatings. Unfortunately, early release of these biocides reduces the

  5. Consumers' perceptions of biocidal products in households.

    Science.gov (United States)

    Wieck, Stefanie; Olsson, Oliver; Kümmerer, Klaus

    2018-03-01

    Biocidal products are commonly used in households and can pose a risk to human health and the environment. The aim of this study was to evaluate consumers' use and understanding of biocidal products in order to identify starting points for minimising their exposure to these products and reducing possible emissions to the environment. In a case study, standardised questionnaires were used to interview consumers in 133 households in three neighbourhoods in Northern Germany, representing the urban-rural typologies in Europe: predominantly urban, intermediate and predominantly rural regions. The questions focussed on the comprehension of the term 'biocide', pest control habits, sources of information, risk perception of different product groups and possible emission reduction measures. Only 21% of the respondents understood the term 'biocide' correctly, whereas 29% thought of 'something that had to do with organic pest control', and 28% were not able to think of a possible meaning. The risk perception of biocidal products compared to plant protection products varied depending on the living conditions. In the urban neighbourhood, biocidal products were perceived as more dangerous than in the rural area. The main pests to be fought were ants, mould and fruit fly. The results of the study indicate that there is a considerable difference between the types of biocidal products that interviewees claimed to own and those that they actually did have in their households. Most notably, respondents did not realise that they owned surface disinfectants. This result indicates that consumers often seem not to be aware of using specific biocidal products. Also, this shows the limitations of collecting data on products owned with only one method, as the results from products inventories of the households deviate from the data collected in interviews. Our results show that the term 'biocide' is not fully understood by many people. To communicate possible risks of biocidal products

  6. Biocidal properties of anti-icing additives for aircraft fuels.

    Science.gov (United States)

    Neihof, R A; Bailey, C A

    1978-04-01

    The biocidal and biostatic activities of seven glycol monoalkyl ether compounds were evaluated as part of an effort to find an improved anti-icing additive for jet aircraft fuel. Typical fuel contaminants, Cladosporium resinae, Gliomastix sp., Candida sp., Pseudomonas aeruginosa, and a mixed culture containing sulfate-reducing bacteria were used as assay organisms. Studies were carried out over 3 to 4 months in two-phase systems containing jet fuel and aqueous media. Diethylene glycol monomethyl ether, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, and 2-methoxyethanol were generally biocidal in aqueous concentrations of 10 to 17% for all organisms except Gliomastix, which required 25% or more. 2-Ethoxyethanol, 2-propoxyethanol, and 2-butoxyethanol were biocidal at progressively lower concentrations down to 1 to 2% for 2-butoxyethanol. The enhanced antimicrobial activity of these three compounds was attributed to cytoplasmic membrane damage because of the correlation between surface tension measurements and lytic activity with P. aeruginosa cells. The mechanism of action of the less active compounds appeared to be due to osmotic (dehydrating) effects. When all requirements are taken into account, diethylene glycol monomethyl ether appears to be the most promising replacement for the currently used additive, 2-methoxyethanol.

  7. Silver Biocide Analysis & Control Device, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Rapid, accurate measurement and process control of silver ion biocide concentrations in future space missions is needed. The purpose of the Phase II program is to...

  8. Biofilm Surface Density Determines Biocide Effectiveness

    Directory of Open Access Journals (Sweden)

    Sara Bas

    2017-12-01

    Full Text Available High resistance of biofilms for chemical challenges is a serious industrial and medical problem. In this work a gradient of surface covered with biofilm has been produced and correlated to the effectiveness of different commercially available oxidative biocides. The results for thin Escherichia coli biofilms grown in rich media supplemented with glucose or lactose on glass or poly methyl methacrylate surfaces indicate that the effectiveness of hydrogen peroxide or chlorine dioxide and quaternary ammonium compounds is inversely proportional to the fraction of the surface covered with the biofilm. In areas where biofilm covered more than 90% of the available surface the biocide treatment was inefficient after 60 min of incubation. The combined effect of oxidant and surfactant increased the effectiveness of the biocide. On the other hand, the increased biofilm viscoelasticity reduced biocide effectiveness. The results emphasize differential biocide effectiveness depending on the fraction of the attached bacterial cells. The results suggest that biofilm biocide resistance is an acquired property that increases with biofilm maturation. The more dense sessile structures present lower log reductions compared to less dense ones.

  9. Thematic strategy on sustainable use of plant protection products. Prospects and requirements for transferring proposals for plant protection products to biocides

    Energy Technology Data Exchange (ETDEWEB)

    Gartiser, Stefan [Hydrotox GmbH, Freiburg im Breisgau (Germany); Lueskow, Heike [Institut fuer Oekologie und Politik GmbH (OEKOPOL), Hamburg (Germany); Gross, Rita [Oeko-Institut e.V. - Institut fuer Angewandte Oekologie e.V., Freiburg im Breisgau (Germany)

    2012-03-15

    The sustainable use of pesticides pursues, independent of the authorisation of single products, the aim to minimise existing environmental risks of pesticide use and therefore contribute to the reduction of its impact on the environmental protection goals. The Thematic Strategy (TS) and the Framework Directive 2009/128/EC (FWD) on sustainable use of pesticides have so far only been implemented for plant protection products (PPP). For biocides there exists no harmonised approach. Within the project the possibilities and requirements for transferring measures of the FWD to the biocide area have been analysed, with specific focus on wood preservatives, insecticides, and antifouling products. Several biocidal active substances are found in the outlets of sewage treatment plants and in surface water, but an inventory of the present environmental impact as well as reliable data on biocide consumption and use patterns, which could be used to identify key action areas, are generally missing. These data are urgently needed for the development of suitable indicators and the definition of the objectives. Sustainable use of biocides addresses the three issues; social, environmental and economic impact at which the ecological background assigns the borderline and beam barrier of the economic and social development. A systematic analysis of the instruments for improving sustainable use of pesticides described in TS and FWD indicated that many issues can be transferred to the biocide area. This concerns e.g. education and training, requirements for sales, the establishment of awareness programmes, control of the machinery for biocide application, the development of best practice standards based on integrated pest management principles, and the collection of statistics on biocide consumption. Some biocide specific characteristics need to be considered: E.g. unlike PPP, the intended use of some biocides is to be directly applied in water bodies or indoors. Furthermore for some

  10. NANOTECHNOLOGY: A NOVEL APPROACH TO PREVENT BIOCIDE LEACHING

    Science.gov (United States)

    This project will demonstrate the environmental benefits of introducing biocide into wood using hydrophobic nanoparticles as a delivery vehicle and controlled release device for organic and inorganic biocides. The primary benefits expected from use of nanoparticles as controll...

  11. Study on management policy of Biocides in Korea

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jeong Kyu; Cho, Young Hee [Korea Environment Institute, Seoul (Korea)

    1999-12-01

    In the advanced countries, there are active studies on biocide, implying non-agricultural pesticides, at present with increasing interests on this. Among the advanced countries, Canada, Australia and New Zealand are managing biocides the most systematically and have very clear regulations and roles of relevant departments. In addition to efforts of each country, the international organizations are emphasizing the need of biocides management. EU already announced Biocidal Products Directive(BPD) in 1998 and is urging to implement regulations within a guidebook in member countries from 2000. Furthermore, OECD is well aware of biocides management trend of each member country and is planning to set up a specific management guide based on this. In this study, it recommends a biocides management policy in Korea with regulations, relevant departments, and regulation contents of biocides implemented in the advanced countries and regulation trend of biocides in Korea. 47 refs., 27 tabs.

  12. Human exposure assessment: Approaches for chemicals (REACH) and biocides (BPD)

    NARCIS (Netherlands)

    Hemmen, J.J. van; Gerritsen-Ebben, R.

    2008-01-01

    The approaches that are indicated in the various guidance documents for the assessment of human exposure for chemicals and biocides are summarised. This reflects the TNsG (Technical notes for Guidance) version 2: human exposure assessment for biocidal products (1) under the BPD (Biocidal Products

  13. Effect of biocides on biofilms of some multidrug resistant clinical ...

    African Journals Online (AJOL)

    The ability of Escherichia coli and Klebsiella aerogenes to form biofilms was most affected. There was little inhibition of biofilm formation by the biocides on Staphylococcus aureus. This study has shown a relationship between biocide and multidrug resistance. Keywords: Biocides, Multi drug resistance, sodium hypochlorite, ...

  14. Enterococcus hirae biofilm formation on hospital material surfaces and effect of new biocides.

    Science.gov (United States)

    Di Lodovico, Silvia; Cataldi, Valentina; Di Campli, Emanuela; Ancarani, Elisabetta; Cellini, Luigina; Di Giulio, Mara

    2017-08-02

    Nowadays, the bacterial contamination in the hospital environment is of particular concern because the hospital-acquired infections (HAIs), also known as nosocomial infections, are responsible for significant morbidity and mortality. This work evaluated the capability of Enterococcus hirae to form biofilm on different surfaces and the action of two biocides on the produced biofilms. The biofilm formation of E. hirae ATCC 10541 was studied on polystyrene and stainless steel surfaces through the biomass quantification and the cell viability at 20 and 37 °C. The effect of LH IDROXI FAST and LH ENZYCLEAN SPRAY biocides on biomasses was expressed as percentage of biofilm reduction. E. hirae at 20 and 37 °C produced more biofilm on the stainless steel in respect to the polystyrene surface. The amount of viable cells was greater at 20 °C than with 37 °C on the two analyzed surfaces. Biocides revealed a good anti-biofilm activity with the most effect for LH ENZYCLEAN SPRAY on polystyrene and stainless steel at 37 °C with a maximum biofilm reduction of 85.72 and 86.37%, respectively. E. hirae is a moderate biofilm producer depending on surface material and temperature, and the analyzed biocides express a remarkable antibiofilm action. The capability of E. hirae to form biofilm can be associated with its increasing incidence in hospital-acquired infections, and the adoption of suitable disinfectants is strongly recommended.

  15. Salomon: '97 E and P looking strongest in 9 years

    International Nuclear Information System (INIS)

    Anon.

    1997-01-01

    Based on companies' disclosed spending plans, 1997 is shaping up to be the strongest year-ahead outlook in 9 years, according to Salomon Bros. Inc. Salomon Bros.' conclusion stems from its 15th annual survey of worldwide oil and gas exploration and production spending. The survey, released last month, included 125 US independents, 97 Canadian companies, 103 companies outside the US and Canada, and 15 majors. Significantly, when the 15% growth experienced in 1996 is combined with the 1997 outlook, it represents the strongest indicator of 2-year activity in the past 15 years, said Salomon Bros. Double-digit spending growth is projected in all regions for 1997, the analyst said. Salomon Bros. said a higher percentage of companies' E and P budgets are being allocated to offshore projects, driven in part by attractive prospects, 3D seismic technology, and increased operational efficiencies

  16. Kinetics of strength gain of biocidal cements

    Directory of Open Access Journals (Sweden)

    Rodin Aleksandr Ivanovich

    Full Text Available Biocorrosion becomes the determinative durability factor of buildings and constructions. Damages of construction materials caused by bacteria, filamentous fungi, actinomycetes constitute a serious danger to the constructions of a building or a structure and to the health of people. Biodeteriorations are typical both in old and new constructions. A great quantity of destruction factors of industrial and residential buildings under the influence of microorganisms was established in practice. Providing products and constructions based on concretes fungicidal and bactericidal properties is an important direction of modern construction material science. The most efficient way to solve this task is creation of biocidal cements. The article presents the results of experimental studies of kinetic dependences of strength gain by biocidal cements by physico-mechanical and physico-chemical analysis methods. The identical velocity character of initial hydration of the developed compositions of biocidal cements is set, as well as a more calm behavior of hardening processes at later terms. It has been established that the compositions of biocidal cements modified by sodium sulfate and sodium fluoride possess the greatest strength.

  17. The Strength of the Strongest Ties in Collaborative Problem Solving

    DEFF Research Database (Denmark)

    de Montjoye, Yves-Alexandre; Stopczynski, Arkadiusz; Shmueli, Erez

    2014-01-01

    Complex problem solving in science, engineering, and business has become a highly collaborative endeavor. Teams of scientists or engineers collaborate on projects using their social networks to gather new ideas and feedback. Here we bridge the literature on team performance and information networks...... by studying teams' problem solving abilities as a function of both their within-team networks and their members' extended networks. We show that, while an assigned team's performance is strongly correlated with its networks of expressive and instrumental ties, only the strongest ties in both networks have...... an effect on performance. Both networks of strong ties explain more of the variance than other factors, such as measured or self-evaluated technical competencies, or the personalities of the team members. In fact, the inclusion of the network of strong ties renders these factors non...

  18. Biocidal packaging for pharmaceuticals, foods, and other perishables.

    Science.gov (United States)

    Larson, Alyssa M; Klibanov, Alexander M

    2013-01-01

    Many consumer goods must be protected from bacterial and fungal colonization to ensure their integrity and safety. By making these items' packaging biocidal, the interior environment can be preserved from microbial spoilage without altering the products themselves. Herein we briefly review this concept, referred to as active packaging, and discuss existing methods for constructing active packaging systems. They are based on either packaging materials that release biocides or those that are themselves intrinsically biocidal (or biostatic), with numerous variations within each category.

  19. Antimicrobial properties and death-inducing mechanisms of saccharomycin, a biocide secreted by Saccharomyces cerevisiae

    DEFF Research Database (Denmark)

    Branco, Patrícia; Francisco, Diana; Monteiro, Margarida

    2017-01-01

    . cerevisiae strains also secrete natural biocide fractions during alcoholic fermentation, although at different levels, which correlates with the antagonistic effect exerted against non-Saccharomyces yeasts. We, therefore, term this biocide saccharomycin. The native AMPs were purified by gel......-filtration chromatography and its antimicrobial activity was compared to that exhibited by chemically synthesized analogues (AMP1 and AMP2/3). Results show that the antimicrobial activity of the native AMPs is significantly higher than that of the synthetic analogues (AMP1 and AMP2/3), but a conjugated action of the two...... species during alcoholic fermentations....

  20. Development of bacterial resistance to biocides and antimicrobial agents as a consequence of biocide usage

    DEFF Research Database (Denmark)

    Seier-Petersen, Maria Amalie

    to antimicrobial agents. So far, only few studies have investigated the susceptibility of livestock-associated isolates to biocides used in their environment. Pigs are increasingly recognised as a potential reservoir of community-acquired methicillin resistant Staphylococcus aureus (CA-MRSA), especially clones...... be of potential risk for human health, since these disinfectants are widely used at hospitals and in the food industry. Mobile genetic elements such as conjugative transposons are important vectors in the dissemination of antibiotic resistance determinants. Tn916 including the tetracycline resistance gene tet......Biocides are chemical compounds with antimicrobial properties and they are widely used for disinfection, antiseptic and preservation purposes. Biocides have been applied for centuries due to early empirical approaches, such as cleansing of wounds with wine, vinegar and honey and salting of fish...

  1. Synergistic sub-lethal effects of a biocide mixture on the springtail Folsomia fimetaria

    International Nuclear Information System (INIS)

    Schnug, Lisbeth; Leinaas, Hans Petter; Jensen, John

    2014-01-01

    The toxicity of three biocides, esfenvalerate, picoxystrobin and triclosan, on adult survival and recruitment of juveniles was studied in the springtail Folsomia fimetaria, both in single and mixture experiments. Recruitment of juveniles was more sensitive to biocide exposure than adult survival. The concepts of concentration addition and independent action returned almost identical toxicity predictions, though both models failed to predict the observed toxicity due to synergistic deviations at high exposure concentrations. A comparison with a similar study on earthworms showed that response-patterns were species-specific. Consequently, there is no single reference concept which is applicable for all species of one ecosystem, which in turn questions the usefulness of such mixture prediction concepts in ecological risk assessment. -- Highlights: • Toxicity of esfenvalerate, picoxystrobin and triclosan to Folsomia fimetaria was assessed. • Both, the single biocides and the mixture affected recruitment stronger than survival. • Concentration addition and independent action predictions were almost identical. • Inhibition of recruitment after mixture exposure was stronger than predicted. • Comparison with an earthworm study showed that responses are species-specific. -- The concepts of concentration addition and independent action failed to predict mixture toxicity due to dose-dependent synergistic effects

  2. Biocide Runoff from Building Facades: Degradation Kinetics in Soil.

    Science.gov (United States)

    Bollmann, Ulla E; Fernández-Calviño, David; Brandt, Kristian K; Storgaard, Morten S; Sanderson, Hans; Bester, Kai

    2017-04-04

    Biocides are common additives in building materials. In-can and film preservatives in polymer-resin render and paint, as well as wood preservatives are used to protect facade materials from microbial spoilage. Biocides leach from the facade material with driving rain, leading to highly polluted runoff water (up to several mg L -1 biocides) being infiltrated into the soil surrounding houses. In the present study the degradation rates in soil of 11 biocides used for the protection of building materials were determined in laboratory microcosms. The results show that some biocides are degraded rapidly in soil (e.g., isothiazolinones: T 1/2 soils; thus, rainfall events control how often new input to the soil occurs. Time intervals between rainfall events in Northern Europe are shorter than degradation half-lives even for many rapidly degraded biocides. Consequently, residues of some biocides are likely to be continuously present due to repeated input and most biocides can be considered as "pseudo-persistent"-contaminants in this context. This was verified by (sub)urban soil screening, where concentrations of up to 0.1 μg g -1 were detected for parent compounds as well as terbutryn degradation products in soils below biocide treated facades.

  3. The Strength of the Strongest Ties in Collaborative Problem Solving

    Science.gov (United States)

    de Montjoye, Yves-Alexandre; Stopczynski, Arkadiusz; Shmueli, Erez; Pentland, Alex; Lehmann, Sune

    2014-06-01

    Complex problem solving in science, engineering, and business has become a highly collaborative endeavor. Teams of scientists or engineers collaborate on projects using their social networks to gather new ideas and feedback. Here we bridge the literature on team performance and information networks by studying teams' problem solving abilities as a function of both their within-team networks and their members' extended networks. We show that, while an assigned team's performance is strongly correlated with its networks of expressive and instrumental ties, only the strongest ties in both networks have an effect on performance. Both networks of strong ties explain more of the variance than other factors, such as measured or self-evaluated technical competencies, or the personalities of the team members. In fact, the inclusion of the network of strong ties renders these factors non-significant in the statistical analysis. Our results have consequences for the organization of teams of scientists, engineers, and other knowledge workers tackling today's most complex problems.

  4. Effects of Antifouling Biocides on Molecular and Biochemical Defense System in the Gill of the Pacific Oyster Crassostrea gigas

    Science.gov (United States)

    Park, Mi Seon; Kim, Young Dae; Kim, Bo-Mi; Kim, Youn-Jung; Kim, Jang Kyun; Rhee, Jae-Sung

    2016-01-01

    Antifouling biocides such as organotin compounds and their alternatives are potent toxicants in marine ecosystems. In this study, we employed several molecular and biochemical response systems of the Pacific oyster Crassostrea gigas to understand a potential mode of action of antifouling biocides (i.e. tributyltin (TBT), diuron and irgarol) after exposure to different concentrations (0.01, 0.1, and 1 μg L-1) for 96 h. As a result, all the three antifouling biocides strongly induced the antioxidant defense system. TBT reduced both enzymatic activity and mRNA expression of Na+/K+-ATPase and acetylcholinesterase (AChE). Lower levels of both Na+/K+-ATPase activity and AChE mRNA expression were observed in the diuron-exposed oysters compared to the control, while the irgarol treatment reduced only the transcriptional expression of AChE gene. We also analyzed transcript profile of heat shock protein (Hsp) superfamily in same experimental conditions. All antifouling biocides tested in this study significantly modulated mRNA expression of Hsp superfamily with strong induction of Hsp70 family. Taken together, overall results indicate that representative organotin TBT and alternatives have potential hazardous effects on the gill of C. gigas within relatively short time period. Our results also suggest that analyzing a series of molecular and biochemical parameters can be a way of understanding and uncovering the mode of action of emerging antifouling biocides. In particular, it was revealed that Pacific oysters have different sensitivities depend on the antifouling biocides. PMID:28006823

  5. Effects of Antifouling Biocides on Molecular and Biochemical Defense System in the Gill of the Pacific Oyster Crassostrea gigas.

    Science.gov (United States)

    Park, Mi Seon; Kim, Young Dae; Kim, Bo-Mi; Kim, Youn-Jung; Kim, Jang Kyun; Rhee, Jae-Sung

    2016-01-01

    Antifouling biocides such as organotin compounds and their alternatives are potent toxicants in marine ecosystems. In this study, we employed several molecular and biochemical response systems of the Pacific oyster Crassostrea gigas to understand a potential mode of action of antifouling biocides (i.e. tributyltin (TBT), diuron and irgarol) after exposure to different concentrations (0.01, 0.1, and 1 μg L-1) for 96 h. As a result, all the three antifouling biocides strongly induced the antioxidant defense system. TBT reduced both enzymatic activity and mRNA expression of Na+/K+-ATPase and acetylcholinesterase (AChE). Lower levels of both Na+/K+-ATPase activity and AChE mRNA expression were observed in the diuron-exposed oysters compared to the control, while the irgarol treatment reduced only the transcriptional expression of AChE gene. We also analyzed transcript profile of heat shock protein (Hsp) superfamily in same experimental conditions. All antifouling biocides tested in this study significantly modulated mRNA expression of Hsp superfamily with strong induction of Hsp70 family. Taken together, overall results indicate that representative organotin TBT and alternatives have potential hazardous effects on the gill of C. gigas within relatively short time period. Our results also suggest that analyzing a series of molecular and biochemical parameters can be a way of understanding and uncovering the mode of action of emerging antifouling biocides. In particular, it was revealed that Pacific oysters have different sensitivities depend on the antifouling biocides.

  6. Effect of biocides and anionic homopolymeric inhibitors on the ...

    African Journals Online (AJOL)

    This paper describes the effect of biocides and of the anionic homopolymeric inhibitors on the precipitation behavior of calcium fluoride (CaF2).The efficiency of inhibitors in the presence and absence of biocides was calculated using the half-life (t1/2) approach, where 50% of the concentration has been precipitated.

  7. Operational efficiency of ballast water biocides at low water temperatures

    NARCIS (Netherlands)

    Kaag, N.H.B.M.; Sneekes, A.C.

    2015-01-01

    In the period 2013-2015 the effect of two biocides used for the treatment of ballast water has been evaluated at low ambient temperatures. Peraclean® Ocean and sodium hypochlorite were used as biocides. Most of the tests were conducted during winter and early spring at the laboratories of IMARES in

  8. Progress in human exposure assessment for biocidal products

    NARCIS (Netherlands)

    Hemmen, J.J. van

    2004-01-01

    An important shortcoming in our present knowledge required for risk assessment of biocidal products is the assessment of human exposure. This knowledge gap has been filled in a preliminary fashion with the TNsG on human exposure to biocidal products (available from the ECB website). Explicit User

  9. Common Problems Encountered in the Microbiological Analysis of Biocidal Products

    OpenAIRE

    Özdemir, Güven

    2015-01-01

    As many parameters that affect the success of a biocidal product, under laboratory conditions there are also factors affecting the reliability and accuracy of tests to determine the microbiological efficacy of these products. The assessment of the microbiological efficacy of the biocidal products and in order to ensure standardization between laboratories it is essential the use of internationally accepted methods.

  10. Biocidal treatment and preservation of liquid fuels

    Energy Technology Data Exchange (ETDEWEB)

    Siegert, W.

    1995-05-01

    Strict microbiological limit values are the result of damage caused by microorganisms in fuels. With MAR 71, a biocide based on methylenebisoxazolidine, a product is available which has been tested and approved by leading car manufacturers, the mineral oil industry, and NATO. Depending on the degree of microbiological contamination, different decontamination concepts are presented, and recommendations for the treatment of fuels which are contaminated when purchased are given. In order to avoid recontamination, planning principles or the new design of tanks are necessary. The possibility of convenient, economical and regular drainage is a key factor.

  11. Regulation of sporicides under the European Biocidal Products Directive.

    Science.gov (United States)

    Low, A

    2011-03-01

    Disinfectants (including sporicides) used in the healthcare setting fall within the scope of the European Biocidal Products Directive (98/8/EC). The active substances used in these products will be evaluated as part of an EU wide review programme, to determine whether they can be used in biocidal products without undue risks to humans, animals and the environment, and that these products will be effective. Following the review of an active substance, biocidal products containing the active substance will become subject to regulatory controls in all EU Member States. This paper discusses how the Directive operates, both through the review programme and the authorisation of biocidal products at the Member State level, together with the requirements to provide data on the efficacy of both the active substances and end-use biocidal products. Crown Copyright © 2010. Published by Elsevier Ltd. All rights reserved.

  12. Development and evaluation of a biocide release system for prolonged antifungal activity in finishing materials

    NARCIS (Netherlands)

    Eversdijk, J.; Erich, S.J.F.; Hermanns, S.P.M.; Adan, O.C.G.; Bolle, de M.; Meyer, de K.; Bylemans, D.; Bekker, M.; Cate, ten A.T.

    2012-01-01

    This paper focuses on the use of modified nano-clay particles as a controlled release system for biocides from building materials. Different (model) biocides were incorporated in a biocide/nano-clay composite and subsequently the release of the biocides was monitored under different environmental

  13. Biocide Selective TolC-Independent Efflux Pumps in Enterobacteriaceae.

    Science.gov (United States)

    Slipski, Carmine J; Zhanel, George G; Bay, Denice C

    2018-02-01

    Bacterial resistance to biocides used as antiseptics, dyes, and disinfectants is a growing concern in food preparation, agricultural, consumer manufacturing, and health care industries, particularly among Gram-negative Enterobacteriaceae, some of the most common community and healthcare-acquired bacterial pathogens. Biocide resistance is frequently associated with antimicrobial cross-resistance leading to reduced activity and efficacy of both antimicrobials and antiseptics. Multidrug resistant efflux pumps represent an important biocide resistance mechanism in Enterobacteriaceae. An assortment of structurally diverse efflux pumps frequently co-exist in these species and confer both unique and overlapping biocide and antimicrobial selectivity. TolC-dependent multicomponent systems that span both the plasma and outer membranes have been shown to confer clinically significant resistance to most antimicrobials including many biocides, however, a growing number of single component TolC-independent multidrug resistant efflux pumps are specifically associated with biocide resistance: small multidrug resistance (SMR), major facilitator superfamily (MFS), multidrug and toxin extruder (MATE), cation diffusion facilitator (CDF), and proteobacterial antimicrobial compound efflux (PACE) families. These efflux systems are a growing concern as they are rapidly spread between members of Enterobacteriaceae on conjugative plasmids and mobile genetic elements, emphasizing their importance to antimicrobial resistance. In this review, we will summarize the known biocide substrates of these efflux pumps, compare their structural relatedness, Enterobacteriaceae distribution, and significance. Knowledge gaps will be highlighted in an effort to unravel the role that these apparent "lone wolves" of the efflux-mediated resistome may offer.

  14. Biocide-mediated corrosion of coiled tubing.

    Science.gov (United States)

    Sharma, Mohita; An, Dongshan; Liu, Tao; Pinnock, Tijan; Cheng, Frank; Voordouw, Gerrit

    2017-01-01

    Coiled tubing corrosion was investigated for 16 field water samples (S5 to S20) from a Canadian shale gas field. Weight loss corrosion rates of carbon steel beads incubated with these field water samples averaged 0.2 mm/yr, but injection water sample S19 had 1.25±0.07 mm/yr. S19 had a most probable number of zero acid-producing bacteria and incubation of S19 with carbon steel beads or coupons did not lead to big changes in microbial community composition. In contrast other field water samples had most probable numbers of APB of 102/mL to 107/mL and incubation of these field water samples with carbon steel beads or coupons often gave large changes in microbial community composition. HPLC analysis indicated that all field water samples had elevated concentrations of bromide (average 1.6 mM), which may be derived from bronopol, which was used as a biocide. S19 had the highest bromide concentration (4.2 mM) and was the only water sample with a high concentration of active bronopol (13.8 mM, 2760 ppm). Corrosion rates increased linearly with bronopol concentration, as determined by weight loss of carbon steel beads, for experiments with S19, with filtered S19 and with bronopol dissolved in defined medium. This indicated that the high corrosion rate found for S19 was due to its high bronopol concentration. The corrosion rate of coiled tubing coupons also increased linearly with bronopol concentration as determined by electrochemical methods. Profilometry measurements also showed formation of multiple pits on the surface of coiled tubing coupon with an average pit depth of 60 μm after 1 week of incubation with 1 mM bronopol. At the recommended dosage of 100 ppm the corrosiveness of bronopol towards carbon steel beads was modest (0.011 mm/yr). Higher concentrations, resulting if biocide is added repeatedly as commonly done in shale gas operations, are more corrosive and should be avoided. Overdosing may be avoided by assaying the presence of residual biocide by HPLC

  15. Partitioning of biocides between water and inorganic phases of render

    DEFF Research Database (Denmark)

    Urbanczyk, Michal; Bollmann, Ulla E.; Bester, Kai

    The use of biocides as additives for building materials has gained importance in recent years. These biocides are, e.g., applied to renders and paints to prevent them from microbial spoilage. However, these biocides can leach out into the environment. In order to better understand this leaching...... compared. The partitioning constants for calcium carbonate varied between 0.1 (isoproturon) and 1.1 (iodocarb) and 84.6 (dichlorooctylisothiazolinone), respectively. The results for barite, kaolinite and mica were in a similar range and usually the compounds with high partitioning constants for one mineral...

  16. Evolution in the Lab: Biocide Resistance in E.coli.

    Science.gov (United States)

    Welden, Charles W.; Hossler, Rex A.

    2003-01-01

    Describes a laboratory experiment on resistance to teach about evolution and issues of misuse of antimicrobial compounds. Investigates Escherichia coli's response to treatment of triclosan, a biocide used in consumer products. (Contains 12 references.) (YDS)

  17. Modelling inorganic biocide emission from treated wood in water

    Energy Technology Data Exchange (ETDEWEB)

    Tiruta-Barna, Ligia, E-mail: Ligia.barna@insa-toulouse.fr [Universite de Toulouse, INSA, UPS, INP, LISBP, 135 Avenue de Rangueil, F-31077 Toulouse (France); INRA, UMR792, Laboratoire d' Ingenierie des Systemes Biologiques et des Procedes, F-31400 Toulouse (France); CNRS, UMR5504, F-31400 Toulouse (France); Schiopu, Nicoleta [Universite Paris-Est, CSTB- Scientific and Technical Centre for the Building Industry, ESE/Environment, 24, rue Joseph Fourier, 38400 Saint Martin d' Heres (France)

    2011-09-15

    Highlights: {center_dot} We developed a mechanistic model for biocide metals fixation/mobilisation in wood. {center_dot} This is the first chemical model explaining the biocide leaching from treated wood. {center_dot} The main fixation mechanism is the surface complexation with wood polymers. {center_dot} The biocide mobilization is due to metal-DOC complexation and pH effect. - Abstract: The objective of this work is to develop a chemical model for explaining the leaching behaviour of inorganic biocides from treated wood. The standard leaching test XP CEN/TS14429 was applied to a commercial construction material made of treated Pinus sylvestris (Copper Boron Azole preservative). The experimental results were used for developing a chemical model under PHREEQC (a geochemical software, with LLNL, MINTEQ data bases) by considering the released species detected in the eluates: main biocides Cu and B, other trace biocides (Cr and Zn), other elements like Ca, K, Cl, SO{sub 4}{sup -2}, dissolved organic matter (DOC). The model is based on chemical phenomena at liquid/solid interfaces (complexation, ion exchange and hydrolysis) and is satisfactory for the leaching behaviour representation. The simulation results confronted with the experiments confirmed the hypotheses of: (1) biocide fixation by surface complexation reactions with wood specific sites (carboxyl and phenol for Cu, Zn, Cr(III), aliphatic hydroxyl for B, ion exchange to a lesser extent) and (2) biocide mobilisation by extractives (DOC) coming from the wood. The maximum of Cu, Cr(III) and Zn fixation occurred at neutral pH (including the natural pH of wood), while B fixation was favoured at alkaline pH.

  18. Biocidal synthetic coatings based on high-molecular metaloorganic compounds. [Aspergillus flavus; Aspergillus niger; Aspergillus terreus; Penicillium funiculosum; penicillium cyclopium; Penicillium chrysogenum; Paecilomyces varioti; Chaetomium globosum; trichoderma viride

    Energy Technology Data Exchange (ETDEWEB)

    Mishchenko, V.F.; Zubov, V.A.; Eremenko, Yu.G.

    Long-term stays of man and animals in closed life-support systems lead to contamination of the space-craft by various microorganisms. Organotin compounds are considered promising biocidal agents for paints and varnishes with a broad spectrum of action against a variety of microorganisms. Several organotin polymers of the acrylate type were prepared and were found to be effective fungicides.

  19. Effects of biocides on chlorophyll contents of detached basil leaves

    Directory of Open Access Journals (Sweden)

    Titima Arunrangsi

    2013-06-01

    Full Text Available Herbicides and insecticides have been widely and intensively used in agricultural areas worldwide to enhance crop yield. However, many biocides cause serious environmental problems. In addition, the biocides may also have some effects on the treated agricultural crops. To study effects of biocides on chlorophyll content in detached basil leaves, 2,4-D dimethylamine salt (2,4 D-Amine, paraquat, carbosulfan, and azadirachtin, were chosen as representatives of biocide. After applying the chemicals to detached basil leaves overnight in darkness, chlorophyll contents were determined. Only treatment with 2,4 D-Amine resulted in reduction of chlorophyll contents significantly compared to treatment with deionized (DI water. In the case of paraquat and carbosulfan, chlorophyll contents were not significantly changed, while slightly higher chlorophyll contents, compared to DI water, after the treatment with azadirachtin, were observed. The results indicated that 2,4 D-Amine shows an ability to accelerate chlorophyll degradation, but azadirachtin helps to retard chlorophyll degradation, when each biocide is used at the concentration recommended by the manufacturer.

  20. Current uses of nanomaterials in biocidal products and treated articles in the EU

    OpenAIRE

    Mackevica, Aiga; Revilla Besora, Pau; Brinch, Anna; Hansen, Steffen Foss

    2016-01-01

    Nanomaterials (NMs) are currently being used for a wide variety of products, and a number of them are utilized as biocides due to their antimicrobial or antifungal properties. Little is known to what extent these biocides are available on the market as consumer products. In the EU, the Biocidal Product Regulation (BPR) lays out a list of requirements that manufacturers of biocidal products have to comply with before they can place their products on the market. It is not entirely clear which c...

  1. Inactivation of murine norovirus by chemical biocides on stainless steel

    Science.gov (United States)

    2009-01-01

    Background Human norovirus (NoV) causes more than 80% of nonbacterial gastroenteritis in Europe and the United States. NoV transmission via contaminated surfaces may be significant for the spread of viruses. Therefore, measures for prevention and control, such as surface disinfection, are necessary to interrupt the dissemination of human NoV. Murine norovirus (MNV) as a surrogate for human NoV was used to study the efficacy of active ingredients of chemical disinfectants for virus inactivation on inanimate surfaces. Methods The inactivating properties of different chemical biocides were tested in a quantitative carrier test with stainless steel discs without mechanical action. Vacuum-dried MNV was exposed to different concentrations of alcohols, peracetic acid (PAA) or glutaraldehyde (GDA) for 5 minutes exposure time. Detection of residual virus was determined by endpoint-titration on RAW 264.7 cells. Results PAA [1000 ppm], GDA [2500 ppm], ethanol [50% (v/v)] and 1-propanol [30% (v/v)] were able to inactivate MNV under clean conditions (0.03% BSA) on the carriers by ≥ 4 log10 within 5 minutes exposure time, whereas 2-propanol showed a reduced effectiveness even at 60% (v/v). Furthermore, there were no significant differences in virus reduction whatever interfering substances were used. When testing with ethanol, 1- and 2-propanol, results under clean conditions were nearly the same as in the presence of dirty conditions (0.3% BSA plus 0.3% erythrocytes). Conclusion Products based upon PAA, GDA, ethanol and 1-propanol should be used for NoV inactivation on inanimate surfaces. Our data provide valuable information for the development of strategies to control NoV transmission via surfaces. PMID:19583832

  2. Inactivation of murine norovirus by chemical biocides on stainless steel

    Directory of Open Access Journals (Sweden)

    Steinmann Jörg

    2009-07-01

    Full Text Available Abstract Background Human norovirus (NoV causes more than 80% of nonbacterial gastroenteritis in Europe and the United States. NoV transmission via contaminated surfaces may be significant for the spread of viruses. Therefore, measures for prevention and control, such as surface disinfection, are necessary to interrupt the dissemination of human NoV. Murine norovirus (MNV as a surrogate for human NoV was used to study the efficacy of active ingredients of chemical disinfectants for virus inactivation on inanimate surfaces. Methods The inactivating properties of different chemical biocides were tested in a quantitative carrier test with stainless steel discs without mechanical action. Vacuum-dried MNV was exposed to different concentrations of alcohols, peracetic acid (PAA or glutaraldehyde (GDA for 5 minutes exposure time. Detection of residual virus was determined by endpoint-titration on RAW 264.7 cells. Results PAA [1000 ppm], GDA [2500 ppm], ethanol [50% (v/v] and 1-propanol [30% (v/v] were able to inactivate MNV under clean conditions (0.03% BSA on the carriers by ≥ 4 log10 within 5 minutes exposure time, whereas 2-propanol showed a reduced effectiveness even at 60% (v/v. Furthermore, there were no significant differences in virus reduction whatever interfering substances were used. When testing with ethanol, 1- and 2-propanol, results under clean conditions were nearly the same as in the presence of dirty conditions (0.3% BSA plus 0.3% erythrocytes. Conclusion Products based upon PAA, GDA, ethanol and 1-propanol should be used for NoV inactivation on inanimate surfaces. Our data provide valuable information for the development of strategies to control NoV transmission via surfaces.

  3. Chapter 14: Evaluating the Leaching of Biocides from Preservative-Treated Wood Products

    Science.gov (United States)

    Stan T. Lebow

    2014-01-01

    Leaching of biocides is an important consideration in the long term durability and any potential for environmental impact of treated wood products. This chapter discusses factors affecting biocide leaching, as well as methods of evaluating rate and quantity of biocide released. The extent of leaching is a function of preservative formulation, treatment methods, wood...

  4. Assessment on urban soil pollution by biocides from building materials

    DEFF Research Database (Denmark)

    Bollmann, Ulla E.; Vollertsen, Jes; Bester, Kai

    2015-01-01

    . Based on a monitoring study of stormwater runoff from a residential catchment as well as direct façade runoff analysis, the present study was assessing the pollution of urban soil to biocides from building material. The stormwater runoff of a residential catchment in Silkeborg (Denmark) was monitored...... from a freshly painted or rendered house, it is obvious that a huge part is actually draining directly to the soil and not to the sewer system. Consequently, the soil in urban areas is exposed to stormwater highly polluted by biocides which might affect the microbial community there....

  5. Efficacy of biocides used in the modern food industry to control salmonella enterica, and links between biocide tolerance and resistance to clinically relevant antimicrobial compounds.

    Science.gov (United States)

    Condell, Orla; Iversen, Carol; Cooney, Shane; Power, Karen A; Walsh, Ciara; Burgess, Catherine; Fanning, Séamus

    2012-05-01

    Biocides play an essential role in limiting the spread of infectious disease. The food industry is dependent on these agents, and their increasing use is a matter for concern. Specifically, the emergence of bacteria demonstrating increased tolerance to biocides, coupled with the potential for the development of a phenotype of cross-resistance to clinically important antimicrobial compounds, needs to be assessed. In this study, we investigated the tolerance of a collection of susceptible and multidrug-resistant (MDR) Salmonella enterica strains to a panel of seven commercially available food-grade biocide formulations. We explored their abilities to adapt to these formulations and their active biocidal agents, i.e., triclosan, chlorhexidine, hydrogen peroxide, and benzalkonium chloride, after sequential rounds of in vitro selection. Finally, cross-tolerance of different categories of biocidal formulations, their active agents, and the potential for coselection of resistance to clinically important antibiotics were investigated. Six of seven food-grade biocide formulations were bactericidal at their recommended working concentrations. All showed a reduced activity against both surface-dried and biofilm cultures. A stable phenotype of tolerance to biocide formulations could not be selected. Upon exposure of Salmonella strains to an active biocidal compound, a high-level of tolerance was selected for a number of Salmonella serotypes. No cross-tolerance to the different biocidal agents or food-grade biocide formulations was observed. Most tolerant isolates displayed changes in their patterns of susceptibility to antimicrobial compounds. Food industry biocides are effective against planktonic Salmonella. When exposed to sublethal concentrations of individual active biocidal agents, tolerant isolates may emerge. This emergence was associated with changes in antimicrobial susceptibilities.

  6. Biocides in the Yangtze River of China: Spatiotemporal distribution, mass load and risk assessment

    International Nuclear Information System (INIS)

    Liu, Wang-Rong; Zhao, Jian-Liang; Liu, You-Sheng; Chen, Zhi-Feng; Yang, Yuan-Yuan; Zhang, Qian-Qian; Ying, Guang-Guo

    2015-01-01

    Nineteen biocides were investigated in the Yangtze River to understand their spatiotemporal distribution, mass loads and ecological risks. Fourteen biocides were detected, with the highest concentrations up to 166 ng/L for DEET in surface water, and 54.3 ng/g dry weight (dw) for triclocarban in sediment. The dominant biocides were DEET and methylparaben, with their detection frequencies of 100% in both phases. An estimate of 152 t/y of 14 biocides was carried by the Yangtze River to the East China Sea. The distribution of biocides in the aquatic environments was significantly correlated to Gross Domestic Product (GDP), total phosphorus (TP) and total nitrogen (TN), suggesting dominant input sources from domestic wastewater of the cities along the river. Risk assessment showed high ecological risks posed by carbendazim in both phases and by triclosan in sediment. Therefore, proper measures should be taken to reduce the input of biocides into the river systems. - Highlights: • Biocides were ubiquitous in the surface water and sediment of the Yangtze River. • The dominant biocides in the Yangtze River were DEET and methylparaben. • Annual flux of biocides was 152 tons from the Yangtze River to the East China Sea. • Domestic wastewater was the main source of the biocides. • Carbendazim and triclosan posed high ecological risks. - Biocides showed wide presence in the Yangtze River and some of them could pose high ecological risks to aquatic organisms

  7. Strongest Tropical cyclones: 1980-2009: A 30-year collage of Hurricane Satellite (HURSAT) data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Strongest Tropical Cyclones: 1980-2009 poster - a 30-year collage of Hurricane Satellite (HURSAT) data. This poster depicts a series of 5 degree grids where within...

  8. Technical Protocol. Transformation of biocides in liquid manures

    Energy Technology Data Exchange (ETDEWEB)

    Kreuzig, Robert; Schlag, Patrick; Teigeler, Jennifer; Hartmann, Constanze; Cvetkovi, Benjamin [Technische Univ. Braunschweig (Germany). Inst. fuer Oekologische Chemie und Abfallanalytik

    2010-07-15

    The Reference Manure Concept, already developed for laboratory tests on fate and behavior of veterinary medicinal products in liquid manures and manured soils, was successfully applied for biocides used for disinfection purposes and control of insects in animal houses. Since the representative and reproducible sampling of manures from high-volume tanks has been considered impossible, excrement samples of cattle and pigs individually kept at an experimental animal house were taken. These samples were thoroughly matrix characterized. Then, tap water was added to prepare reference manures of definite dry substance contents. Subsequently, the long-term transformation of the biocides imazalil and cyanamide applied as {sup 14}C-labeled radiotracers was investigated in these manure samples. On the basis of the transformation tests, test manures with 7-day aged biocide residues were prepared and applied in laboratory tests on transformation and sorption in manured soil. By means of this experimental approach, the impacts of aging processes during manure storage and of the manure matrix on the fate of biocides in soils can be assessed already under laboratory conditions. These laboratory tests have been directed as closely as possible to agricultural practice as well as to analytical practicability and quality assurance. Finally, the methodological aspects have been compiled in a Technical Protocol (Draft version). (orig.)

  9. Evaluation Of Biocides for Potential Treatment of Ballast Water

    Science.gov (United States)

    2004-10-01

    gather data on toxicology and ecotoxicology ; (3) provide information on the processes used in the production of the new substance, as well as the...Data Bank 2004 Target Organism Treatment Dosage Citation algae reduced by 92% filamentous algae or common macrophytes (Potamogeton foliosus...Sea Nine 211; RH-25287 Citations Laws and Regulations Shipboard Use DEPA, , . 2000. Ecotoxicological Assessment of Antifouling Biocides and

  10. Biocides from facade coatings in urban surface waters

    DEFF Research Database (Denmark)

    Bollmann, Ulla E; Styszko, Katarzyna; Ou, Yi

    2015-01-01

    catchment was performed in order to get knowledge about emission rates and processes. A first estimation of the leachability of a biocide is usually done using its octanol-water partition constant as well as water solubility. The present study introduces the possiblity of using the polyacrylate...

  11. Research and applications of N-halamine biocidal materials

    Directory of Open Access Journals (Sweden)

    KANG Zhenzhen

    2012-10-01

    Full Text Available N-halamines,a new class of biocides,overcome some of the disadvantages caused by the traditional biocides in practical applications.They are environmentally friendly germicides due to their fast and efficient sterilization,storage stability,and regeneration.Earlier studies on N-halamines mainly focused on the syntheses and applications of small molecular organic N-halamines such as fivemembered and six-membered heterocyclic N-halamine compounds.Compared to traditional inorganic halogen-containing disinfectants such as chlorine gas,sodium hypochlorite,chlorine dioxide,these heterocyclic N-halamines can maintain disinfection capacity in the water for longer time due to their better stability.Since the late 20th century,non-leaching biocial N-halamine materials have received much attention.Some novel N-halmine precursors with binding groups have been covalently bounded to various materials such as cellulose fiber,silica gel,polystyrene,polyethylene,and polyurethane to produce nonleaching biocidal materials.Specially,the successful development of macroporous cross-linked N-halamine polymer resin materials (Halopure and related technologies created a new era for the applications of N-halamine materials in the disinfection of drinking water.In this review paper,the antibacterial mechanism and synthetic methods of N-halamine biocidal materials and their application prospects in various fields of daily life were introduced.Their development prospects were also made.

  12. Biocides Steering Group on human exposure assessment: A preliminary report

    NARCIS (Netherlands)

    Hemmen, J.J. van

    1999-01-01

    In a project granted by DG XI of the European Commission, it is attempted to collate experimental and theoretical data on human (workers and consumers) exposure assessment to biocidal products, and to outline the methodology for sampling and measurement. On the basis of the available evidence,

  13. Biocide leaching during field experiments on treated articles.

    Science.gov (United States)

    Schoknecht, Ute; Mathies, Helena; Wegner, Robby

    2016-01-01

    Biocidal products can be sources of active substances in surface waters caused by weathering of treated articles. Marketing and use of biocidal products can be limited according to the European Biocidal Products Regulation if unacceptable risks to the environment are expected. Leaching of active substances from treated articles was observed in field experiments to obtain information on leaching processes and investigate the suitability of a proposed test method. Leaching under weathering conditions proceeds discontinuously and tends to decrease with duration of exposure. It does not only mainly depend on the availability of water but is also controlled by transport processes within the materials and stability of the observed substances. Runoff amount proved to be a suitable basis to compare results from different experiments. Concentrations of substances are higher in runoff collected from vertical surfaces compared to horizontal ones, whereas the leached amounts per surface area are higher from horizontal surfaces. Gaps in mass balances indicate that additional processes such as degradation and evaporation may be relevant to the fate of active substances in treated articles. Leached amounts of substances were considerably higher when the materials were exposed to intermittent water contact under laboratory conditions as compared to weathering of vertically exposed surfaces. Experiences from the field experiments were used to define parameters of a procedure that is now provided to fulfil the requirements of the Biocidal Products Regulation. The experiments confirmed that the amount of water which is in contact with exposed surfaces is the crucial parameter determining leaching of substances.

  14. Chemical Interactions of Hydraulic Fracturing Biocides with Natural Pyrite

    Science.gov (United States)

    Consolazio, Nizette A.

    In conjunction with horizontal drilling, hydraulic fracturing or fracking has enabled the recovery of natural gas from low permeable shale formations. In addition to water, these fracking fluids employ proppants and up to 38 different chemical additives to improve the efficiency of the process. One important class of additives used in hydraulic fracturing is biocides. When applied appropriately, they limit the growth of harmful microorganisms within the well, saving energy producers 4.5 billion dollars each year. However, biocides or their harmful daughter products may return to the surface in produced water, which must then be appropriately stored, treated and disposed of. Little is known about the effect of mineral-fluid interactions on the fate of the biocides employed in hydraulic fracturing. In this study, we employed laboratory experiments to determine changes in the persistence and products of these biocides under controlled environments. While many minerals are present in shale formations, pyrite, FeS2(s) is particularly interesting because of its prevalence and reactivity. The FeII groups on the face of pyrite may be oxidized to form FeIII phases. Both of these surfaces have been shown to be reactive with organic compounds. Chlorinated compounds undergo redox reactions at the pyrite-fluid interface, and sulfur-containing compounds undergo exceptionally strong sorption to both pristine and oxidized pyrite. This mineral may significantly influence the degradation of biocides in the Marcellus Shale. Thus, the overall goal of this study was to understand the effect of pyrite on biocide reactivity in hydraulic fracturing, focusing on the influence of pyrite on specific functional groups. The first specific objective was to demonstrate the effect of pyrite and pyrite reaction products on the degradation of the bromine-containing biocide, DBNPA. On the addition of pyrite to DBNPA, degradation rates of the doubly brominated compound were found to increase

  15. Biocide by-products in aquatic environments. Annual report, October 1, 1977--September 30, 1978

    International Nuclear Information System (INIS)

    Anderson, D.R.; Bean, R.M.; Gibson, C.I.

    1979-01-01

    The Biocide By-Products in Aquatic Environments Program is composed of analytical chemistry and biological phases with freshwater and marine biological subdivisions. The objectives of the analytical studies are: to identify those chloroorganic chemical compounds that result from the addition of chlorine to fresh or saltwater; to develop methods for detecting chlorinated organics in the effluents discharged to receiving water bodies from nuclear stations; and to verify laboratory findings through analysis for chlorination by-products in water and biota samples from cooling water bodies of nuclear power stations. The objectives of the biological studies are: to investigate the immediate toxicity of specific chlorination by-products (chloroform in freshwater and bromoform in marine waters); to evaluate the chronic toxicity of chlorination by-products; to follow their pathways of action; and to analyze for bioaccumulation or biomagnification of halogenated hydrocarbons on selected aquatic or marine biota

  16. Case study: Use of isothiazolinone and nitro-morpholine biocides to control microbial contamination in diesel and gasoline storage and distribution systems

    Energy Technology Data Exchange (ETDEWEB)

    Chesneau, H.L.; Passman, F.J.; Daniels, D.

    1995-05-01

    Responding to feed-back from its retail outlet network, a major, vertically integrated petroleum company undertook to diagnose and remediate diesel and gasoline performance problems. Analysis of samples from tanks at refinery, distribution terminal and retail outlet sites established that uncontrolled microbial contamination was rampant throughout the distribution system. The company then developed and instituted a two-phase action plan. During Phase I, all tanks received corrective (shock) biocide treatment preceding mechanical tank cleaning and fuel polishing. An ongoing Phase II program currently includes routine sampling and analysis combined with periodic preventive biocide treatment. This paper describes the initial problem diagnosis, corrective action plan and preventive program; recommending the Phase II program as a model for all companies involved with refining, distribution or retailing gasoline.

  17. Water driven leaching of biocides from paints and renders

    DEFF Research Database (Denmark)

    Bester, Kai; Vollertsen, Jes; Bollmann, Ulla E

    ) were so high, that rather professional urban gardening (flower and greenhouses) than handling of biocides from construction materials seem to be able to explain the findings. While the use in agriculture is restricted, the use in greenhouses is currently considered legal in Denmark. Leaching....../partitioning: Considering material properties, it was found out that, for all of the compounds the sorption (and leaching) is highly pH-dependent. It must be take into account that the pH in the porewater of the tested render materials is between 9 and 10 while the rainwater is around 5, thus making prediction difficult...... at this stage. For some of the compounds the sorption is dependent on the amount of polymer in the render, while it is only rarely of importance which polymer is used. Considering the interaction of weather with the leaching of biocides from real walls it turned out that a lot of parameters such as irradiation...

  18. Current uses of nanomaterials in biocidal products and treated articles in the EU

    DEFF Research Database (Denmark)

    Mackevica, Aiga; Revilla Besora, Pau; Brinch, Anna

    2016-01-01

    Product Regulation (BPR) lays out a list of requirements that manufacturers of biocidal products have to comply with before they can place their products on the market. It is not entirely clear which commercially available articles in the EU have been treated with or incorporate NMs to provide biocidal...... properties to the product. To obtain an insight into what biocidal products are on the EU market, we used The Nanodatabase (nanodb.dk) for analyzing which NMs are being used and what product categories they represent. In this paper, we address the issue of the current uses of NMs in biocidal products...... and discuss how they are currently regulated under the BPR. Even though the BPR already entails nanospecific provisions, correct labelling of biocidal products containing NMs is virtually non-existent. By using The Nanodatabase, it was possible to identify 88 biocidal products containing NMs available...

  19. Phenotypic changes contributing to Enterobacter gergoviae biocide resistance.

    Science.gov (United States)

    Périamé, M; Philippe, N; Condell, O; Fanning, S; Pagès, J-M; Davin-Regli, A

    2015-08-01

    Enterobacter gergoviae is a recurrent contaminant of cosmetic and hygiene products. To understand how this bacterium adapts to biocides, we studied Ent. gergoviae CIP 76.01 and its triclosan and Methylisothiazolinone-chloromethylisothiazolinone (MIT-CMIT) tolerant isogenic mutants. They were compared with others also isolated from contaminated cosmetics. Phenotypic differences were noted and these included changes in the bacterial envelope and flagella along with differences in motility, and biofilm growth rates. Triclosan and MIT-CMIT derivatives expressed flagella and other MIT-CMIT derivatives exhibited some external appendages. Those bacteria expressing a high-level minimal inhibitory concentration to MIT-CMIT, expressed a strong biofilm formation. No differential phenotypes were noted for carbon source utilisation. Enterobacter gergoviae demonstrated a diverse response to both of these preservatives contained in cosmetic preparations, depending on their concentrations. Interestingly, this adaptive response is associated with modifications of filament structure-related proteins contributing to increase the organism motility and the production of biofilm. Recurrent contaminations of cosmetics products by Ent. gergoviae, needed a better understanding concerning the bacterial adaptation to preservative agents, with particular concern to triclosan and MIT-CMIT. We demonstrated that bacteria response is associated to various mechanisms represented by expression of external appendages (pili or fimbriae) that control cell motility and biofilm formation and evolving as the concentration of biocides adaptation increased. Such mechanisms which are not chemical specific can also promote a cross-resistance to other biocidal agents. The characterization of Ent. gergoviae adaptability to biocides allows industry to adjust the ranges of concentrations and composition of preservatives in formula. © 2015 The Society for Applied Microbiology.

  20. Legionella control in power station cooling towers using oxidising biocides

    Energy Technology Data Exchange (ETDEWEB)

    Sailer, Christian; Rawlinson, Julia; Killeen, Paul [Ecolab PTY LTD, Ascot, WA (Australia)

    2009-02-15

    Power stations have used oxidising biocides such as chlorine or bromine for many years to control microbial growth in their cooling towers. In this paper Ecolab trademark looks at the direct effect halogen concentration has on Legionella populations in order to determine the most effective halogenation rate required to ensure that the site key performance indicator (KPI) of < 100 colony-forming units (cfu) per mL can be maintained. (orig.)

  1. Chemical composition of silica-based biocidal modifier

    Directory of Open Access Journals (Sweden)

    Grishina Anna Nikolaevna

    2016-11-01

    Full Text Available Increase of the amount of fungi spores and micotixines causes the increase in the number of different diseases. Because of this, ensuring the biological safety in buildings is becoming more and more important today. The preferred way to guarantee the biological safety of a building is to employ modern building materials that prevent the settlement of the fungi colonies on the inner surfaces of walls. Such building materials can be produced using novel biocidal modifiers that allow controlling the number of microorganisms on the surface and in the bulk of a composite construction. The precipitation product of zinc hydrosilicates and sodium sulfate is one of the mentioned modifiers. Till now, the exact chemical composition of such precipitation product is controversial; it is obvious, though, that the efficacy of the biocidal modifier is mostly determined by the type of the copper compounds. In the present work an integrated approach is used for the investigation of the chemical composition of the biocidal modifier. Such an approach consists in the examination of the modifier’s composition by means of different, yet complementary, research methods: X-ray diffraction, infrared spectroscopy and DTA. It is shown that the chemical composition of the modifier mainly depends on the amount of precipitant. X-ray diffraction reveals that the major part of the modifier is represented by amorphous phase. Along with the increase of the precipitant’s amount the crystalline phase Zn4SO4(OH6•xH2O formation takes place. Such a crystalline phase is not appropriate as a component of the biocidal modifier. Another two methods - DTA and IR spectroscopy - reveal that the amorphous phase consists essentially of zinc hydrosilicates.

  2. Usage Possibilities of Insecticide Effective Biocidals in Organic Agriculture

    OpenAIRE

    Şimşek, Muharrem; Yağcı, Mürşide; Yaşarer, Haluk

    2016-01-01

    In conventional agriculture it is aimed that mainly increase in the amount of products, synthetic chemicals and fertilizers are used extensively to provide it. Today, terms such as safe food, human and environment health have become more important. Therefore, it is necessary to increase the share of organic agriculture which have less negative impacts to human health and environment, and sustainable use of natural resources. Herein environmentally insecticide effective biocidals to pest contr...

  3. Biocide leaching from CBA treated wood — A mechanistic interpretation

    International Nuclear Information System (INIS)

    Lupsea, Maria; Mathies, Helena; Schoknecht, Ute; Tiruta-Barna, Ligia; Schiopu, Nicoleta

    2013-01-01

    Treated wood is frequently used for construction. However, there is a need to ensure that biocides used for the treatment are not a threat for people or environment. The paper focused on Pinus sylvestris treated with copper–boron–azole (CBA), containing tebuconazole as organic biocide and monoethanolamine (Mea). This study investigates chemical mechanisms of fixation and mobilisation involved in the leaching process of the used inorganic and organic biocides in CBA. A pH dependent leaching test was performed, followed by a set of complementary analysis methods in order to identify and quantify the species released from wood. The main findings of this study are: -Organic compounds are released from untreated and treated wood; the quantity of released total organic carbon, carboxylic and phenolic functions increasing with the pH. -Nitrogen containing compounds, i.e. mainly Mea and its reaction products with extractives, are released in important quantities from CBA treated wood, especially at low pH. -The release of copper is the result of competitive reactions: fixation via complexation reactions and complexation with extractives in the liquid phase. The specific pH dependency of Cu leaching is explained by the competition of ligands for protonation and complexation. -Tebuconazole is released to a lesser extent relative to its initial content. Its fixation on solid wood structure seems to be influenced by pH, suggesting interactions with -OH groups on wood. Boron release appears to be pH independent and very high. This confirms its weak fixation on wood and also no or weak interaction with the extractives. - Highlights: ► A pH dependent leaching mechanism for CBA treated wood is described. ► The fixation and mobilisation of inorganic and organic biocides was investigated. ► Extractives' quantity and nature depend on pH. ► Competition of ligands for protonation and complexation explains Cu behaviour. ► Tebuconazole seems to interact with -OH groups on

  4. Glass-(nAg, nCu) Biocide Coatings on Ceramic Oxide Substrates

    OpenAIRE

    Esteban-Tejeda, Leticia; Malpartida, Francisco; Díaz, Luis Antonio; Torrecillas, Ramón; Rojo, Fernando; Moya, José Serafín

    2012-01-01

    The present work was focused on obtaining biocide coatings constituted by a glassy soda-lime matrix containing silver or copper nanoparticles on ceramic (alumina and zirconia based) substrates. Both glassy coatings showed a high biocide activity against Gram-, Gram+ bacteria and yeast, reducing cell numbers more than three logarithms. Silver nanoparticles had a significantly higher biocide activity than copper nanoparticles, since the lixiviation levels required to reduce cell numbers more th...

  5. 'High throughput': new technique to evaluation of biocides for biofouling control in oil fields; 'High throughput': nova tecnologia para avaliacao da eficacia de biocidas no controle de biofilme na industria do petroleo

    Energy Technology Data Exchange (ETDEWEB)

    Yin, Bei [DOW, IL(United States); Yang, Jeff [DOW, Shangai (China); Bertheas, Ute [DOW, Horgen (Switzerland); Takahashi, Debora F. [DOW, Rio de Janeiro, RJ (Brazil)

    2008-07-01

    The wide metabolism diversifications and versatile surviving mechanisms lead to the broad existence of microorganisms in oil fields. Water flooding in secondary production can encourage microbial growth and biofilm build-up. Microbial contamination in oil field can cause many problems including microbiologically induced corrosion, oil and gas souring, deposition of iron sulfide, degradation of polymer additives, and plugging oil and gas pipelines and water purification systems. In general, biocides are needed both topside and down hole to control problematic microorganisms. In this study, a high throughput test method was developed that enables a more realistic determination of biocides efficacy against anaerobic microorganisms commonly found in oil field environments. Using this method, a thorough comparison of several commonly used biocides products in oil field for their efficacy against oil field anaerobic sulfate-reducing bacteria isolates was executed. This study showed that for each individual application, it is important to screen biocides and their combinations against microorganisms cultured from the field. Since biocides vary in their mode of action, this study also demonstrated the critical importance of utilizing the high throughput method for determining the best and most customized solution for each application. (author)

  6. Biocide usage in cooling towers in the electric power and petroleum refining industries

    Energy Technology Data Exchange (ETDEWEB)

    Veil, J.; Rice, J.K.; Raivel, M.E.S.

    1997-11-01

    Cooling towers users frequently apply biocides to the circulating cooling water to control growth of microorganisms, algae, and macroorganisms. Because of the toxic properties of biocides, there is a potential for the regulatory controls on their use and discharge to become increasingly more stringent. This report examines the types of biocides used in cooling towers by companies in the electric power and petroleum refining industries, and the experiences those companies have had in dealing with agencies that regulate cooling tower blowdown discharges. Results from a sample of 67 electric power plants indicate that the use of oxidizing biocides (particularly chlorine) is favored. Quaternary ammonia salts (quats), a type of nonoxidizing biocide, are also used in many power plant cooling towers. The experience of dealing with regulators to obtain approval to discharge biocides differs significantly between the two industries. In the electric power industry, discharges of any new biocide typically must be approved in writing by the regulatory agency. The approval process for refineries is less formal. In most cases, the refinery must notify the regulatory agency that it is planning to use a new biocide, but the refinery does not need to get written approval before using it. The conclusion of the report is that few of the surveyed facilities are having any difficulty in using and discharging the biocides they want to use.

  7. The use of machine learning methodologies to analyse antibiotic and biocide susceptibility in Staphylococcus aureus.

    Directory of Open Access Journals (Sweden)

    Joana Rosado Coelho

    Full Text Available BACKGROUND: The rise of antibiotic resistance in pathogenic bacteria is a significant problem for the treatment of infectious diseases. Resistance is usually selected by the antibiotic itself; however, biocides might also co-select for resistance to antibiotics. Although resistance to biocides is poorly defined, different in vitro studies have shown that mutants presenting low susceptibility to biocides also have reduced susceptibility to antibiotics. However, studies with natural bacterial isolates are more limited and there are no clear conclusions as to whether the use of biocides results in the development of multidrug resistant bacteria. METHODS: The main goal is to perform an unbiased blind-based evaluation of the relationship between antibiotic and biocide reduced susceptibility in natural isolates of Staphylococcus aureus. One of the largest data sets ever studied comprising 1632 human clinical isolates of S. aureus originated worldwide was analysed. The phenotypic characterization of 13 antibiotics and 4 biocides was performed for all the strains. Complex links between reduced susceptibility to biocides and antibiotics are difficult to elucidate using the standard statistical approaches in phenotypic data. Therefore, machine learning techniques were applied to explore the data. RESULTS: In this pioneer study, we demonstrated that reduced susceptibility to two common biocides, chlorhexidine and benzalkonium chloride, which belong to different structural families, is associated to multidrug resistance. We have consistently found that a minimum inhibitory concentration greater than 2 mg/L for both biocides is related to antibiotic non-susceptibility in S. aureus. CONCLUSIONS: Two important results emerged from our work, one methodological and one other with relevance in the field of antibiotic resistance. We could not conclude on whether the use of antibiotics selects for biocide resistance or vice versa. However, the observation of

  8. Effect of subinhibitory concentrations of four commonly used biocides on the conjugative transfer of Tn916 in Bacillus subtilis

    DEFF Research Database (Denmark)

    Seier-Petersen, Maria Amalie; Jasni, A.; Aarestrup, Frank Møller

    2014-01-01

    Objectives Large amounts of biocides are used to reduce and control bacterial growth in the healthcare sector, food production and agriculture. This work explores the effect of subinhibitory concentrations of four commonly used biocides (ethanol, hydrogen peroxide, chlorhexidine digluconate...

  9. Bioassays and selected chemical analysis of biocide-free antifouling coatings

    NARCIS (Netherlands)

    Watermann, B.T.; Daehne, B.; Sievers, S.; Dannenberg, R.; Overbeke, J.C.; Klijnstra, J.W.; Heemken, O.

    2005-01-01

    Over the years several types of biocide-free antifouling paints have entered the market. The prohibition of biocidal antifouling paints in special areas of some European countries such as Sweden, Denmark and Germany has favoured the introduction of these paints to the market. Several types of

  10. SOLUBILITY OF ORGANIC BIOCIDES IN SUPERCRITICAL CO2 AND CO2+ COSOLVENT MIXTURES

    Science.gov (United States)

    Solubilities of four organic biocides in supercritical carbon dioxide (Sc-CO2) were measured using a dynamic flowr apparatus over a pressure range of 10 to 30 MPa and temperature of 35-80 degrees C. The biocides studied were: Amical-48 (diiodomethyl p-tolyl sulfone), chlorothalo...

  11. Antimicrobial biocides in the healthcare environment: efficacy, usage, policies, and perceived problems.

    Science.gov (United States)

    Maillard, Jean-Yves

    2005-12-01

    Biocides are heavily used in the healthcare environment, mainly for the disinfection of surfaces, water, equipment, and antisepsis, but also for the sterilization of medical devices and preservation of pharmaceutical and medicinal products. The number of biocidal products for such usage continuously increases along with the number of applications, although some are prone to controversies. There are hundreds of products containing low concentrations of biocides, including various fabrics such as linen, curtains, mattresses, and mops that claim to help control infection, although evidence has not been evaluated in practice. Concurrently, the incidence of hospital-associated infections (HAIs) caused notably by bacterial pathogens such as methicillin-resistant Staphylococcus aureus (MRSA) remains high. The intensive use of biocides is the subject of current debate. Some professionals would like to see an increase in their use throughout hospitals, whereas others call for a restriction in their usage to where the risk of pathogen transmission to patients is high. In addition, the possible linkage between biocide and antibiotic resistance in bacteria and the role of biocides in the emergence of such resistance has provided more controversies in their extensive and indiscriminate usage. When used appropriately, biocidal products have a very important role to play in the control of HAIs. This paper discusses the benefits and problems associated with the use of biocides in the healthcare environment and provides a constructive view on their overall usefulness in the hospital setting.

  12. EU Regulation of Nanobiocides: Challenges in Implementing the Biocidal Product Regulation (BPR)

    DEFF Research Database (Denmark)

    Brinch, Anna; Hansen, Steffen Foss; Hartmann, Nanna B.

    2016-01-01

    The Biocidal Products Regulation (BPR) contains several provisions for nanomaterials (NMs) and is the first regulation in the European Union to require specific testing and risk assessment for the NM form of a biocidal substance as a part of the information requirements. Ecotoxicological data...

  13. Combined effects of pharmaceuticals, personal care products, biocides and organic contaminants on the growth of Skeletonema pseudocostatum.

    Science.gov (United States)

    Petersen, Karina; Heiaas, Harald Hasle; Tollefsen, Knut Erik

    2014-05-01

    Organisms in the environment are exposed to a number of pollutants from different compound groups. In addition to the classic pollutants like the polychlorinated biphenyls, polyaromatic hydrocarbons (PAHs), alkylphenols, biocides, etc. other compound groups of concern are constantly emerging. Pharmaceuticals and personal care products (PPCPs) can be expected to co-occur with other organic contaminants like biocides, PAHs and alkylphenols in areas affected by wastewater, industrial effluents and intensive recreational activity. In this study, representatives from these four different compound groups were tested individually and in mixtures in a growth inhibition assay with the marine algae Skeletonema pseudocostatum (formerly Skeletonema costatum) to determine whether the combined effects could be predicted by models for additive effects; the concentration addition (CA) and independent action (IA) prediction model. The eleven tested compounds reduced the growth of S. pseudocostatum in the microplate test in a concentration-dependent manner. The order of toxicity of these chemicals were irgarol>fluoxetine>diuron>benzo(a)pyrene>thioguanine>triclosan>propranolol>benzophenone 3>cetrimonium bromide>4-tert-octylphenol>endosulfan. Several binary mixtures and a mixture of eight compounds from the four different compound groups were tested. All tested mixtures were additive as model deviation ratios, the deviation between experimental and predicted effect concentrations, were within a factor of 2 from one or both prediction models (e.g. CA and IA). Interestingly, a concentration dependent shift from IA to CA, potentially due to activation of similar toxicity pathways at higher concentrations, was observed for the mixture of eight compounds. The combined effects of the multi-compound mixture were clearly additive and it should therefore be expected that PPCPs, biocides, PAHs and alkylphenols will collectively contribute to the risk in areas contaminated by such complex

  14. Biocide leaching from CBA treated wood — A mechanistic interpretation

    Energy Technology Data Exchange (ETDEWEB)

    Lupsea, Maria [University of Toulouse, INSA, UPS, INP, LISBP, 135 Avenue de Rangueil, F-31077 Toulouse (France); INRA, UMR 792, F-31400 Toulouse (France); CNRS, UMR 5504, F-31400 Toulouse (France); Paris-Est University, CSTB — Scientific and Technical Centre for the Building Industry, ESE/Environment, 24 rue Joseph Fourier, F-38400 Saint Martin d' Hères (France); Mathies, Helena; Schoknecht, Ute [BAM — Federal Institute for Materials Research and Testing, Division 4.1, Unter den Eichen 87, 12205 Berlin (Germany); Tiruta-Barna, Ligia, E-mail: ligia.barna@insa-toulouse.fr [University of Toulouse, INSA, UPS, INP, LISBP, 135 Avenue de Rangueil, F-31077 Toulouse (France); INRA, UMR 792, F-31400 Toulouse (France); CNRS, UMR 5504, F-31400 Toulouse (France); Schiopu, Nicoleta [Paris-Est University, CSTB — Scientific and Technical Centre for the Building Industry, ESE/Environment, 24 rue Joseph Fourier, F-38400 Saint Martin d' Hères (France)

    2013-02-01

    Treated wood is frequently used for construction. However, there is a need to ensure that biocides used for the treatment are not a threat for people or environment. The paper focused on Pinus sylvestris treated with copper–boron–azole (CBA), containing tebuconazole as organic biocide and monoethanolamine (Mea). This study investigates chemical mechanisms of fixation and mobilisation involved in the leaching process of the used inorganic and organic biocides in CBA. A pH dependent leaching test was performed, followed by a set of complementary analysis methods in order to identify and quantify the species released from wood. The main findings of this study are: -Organic compounds are released from untreated and treated wood; the quantity of released total organic carbon, carboxylic and phenolic functions increasing with the pH. -Nitrogen containing compounds, i.e. mainly Mea and its reaction products with extractives, are released in important quantities from CBA treated wood, especially at low pH. -The release of copper is the result of competitive reactions: fixation via complexation reactions and complexation with extractives in the liquid phase. The specific pH dependency of Cu leaching is explained by the competition of ligands for protonation and complexation. -Tebuconazole is released to a lesser extent relative to its initial content. Its fixation on solid wood structure seems to be influenced by pH, suggesting interactions with -OH groups on wood. Boron release appears to be pH independent and very high. This confirms its weak fixation on wood and also no or weak interaction with the extractives. - Highlights: ► A pH dependent leaching mechanism for CBA treated wood is described. ► The fixation and mobilisation of inorganic and organic biocides was investigated. ► Extractives' quantity and nature depend on pH. ► Competition of ligands for protonation and complexation explains Cu behaviour. ► Tebuconazole seems to interact with -OH groups

  15. Biocides Steering Group on human exposure assessment: a preliminary report.

    Science.gov (United States)

    van Hemmen, J J

    1999-06-30

    In a project granted by DG XI of the European Commission, it is attempted to collate experimental and theoretical data on human (workers and consumers) exposure assessment to biocidal products, and to outline the methodology for sampling and measurement. On the basis of the available evidence, approaches are presented for the exposure assessment to be used for estimation of risks in authorization procedures under the recently accepted Directive 98/8/EC. Gaps in knowledge are indicated, making it possible to study the issues involved in a comprehensive and cost-effective way. Some recommendations are given on how to best do this. The current project has been detailed in a final report.

  16. The strongest spectral lines of stable elements with other interfering elements in compiled and plotted version

    International Nuclear Information System (INIS)

    Bauer, M.; Weitkamp, C.

    1977-01-01

    The strongest spectra lines of the 85 stable chemical elements have been compiled and plotted along with lines from other elements that may interfere in applications like spectroscopic multielement analysis. For each line a wavelength range of +- 0.25 A.U. around the line of interest has been considered. The tables contain the wavelength, intensity and assignment to an ionization state of the emitting atom, the plots visualize the lines with a doppler broadening corresponding to 8,000 K. (orig.) [de

  17. High performance polypyrrole coating for corrosion protection and biocidal applications

    Science.gov (United States)

    Nautiyal, Amit; Qiao, Mingyu; Cook, Jonathan Edwin; Zhang, Xinyu; Huang, Tung-Shi

    2018-01-01

    Polypyrrole (PPy) coating was electrochemically synthesized on carbon steel using sulfonic acids as dopants: p-toluene sulfonic acid (p-TSA), sulfuric acid (SA), (±) camphor sulfonic acid (CSA), sodium dodecyl sulfate (SDS), and sodium dodecylbenzene sulfonate (SDBS). The effect of acidic dopants (p-TSA, SA, CSA) on passivation of carbon steel was investigated by linear potentiodynamic and compared with morphology and corrosion protection performance of the coating produced. The types of the dopants used were significantly affecting the protection efficiency of the coating against chloride ion attack on the metal surface. The corrosion performance depends on size and alignment of dopant in the polymer backbone. Both p-TSA and SDBS have extra benzene ring that stack together to form a lamellar sheet like barrier to chloride ions thus making them appropriate dopants for PPy coating in suppressing the corrosion at significant level. Further, adhesion performance was enhanced by adding long chain carboxylic acid (decanoic acid) directly in the monomer solution. In addition, PPy coating doped with SDBS displayed excellent biocidal abilities against Staphylococcus aureus. The polypyrrole coatings on carbon steels with dual function of anti-corrosion and excellent biocidal properties shows great potential application in the industry for anti-corrosion/antimicrobial purposes.

  18. Consumer exposure to biocides - identification of relevant sources and evaluation of possible health effects

    Directory of Open Access Journals (Sweden)

    Heger Wolfgang

    2010-02-01

    Full Text Available Abstract Background Products containing biocides are used for a variety of purposes in the home environment. To assess potential health risks, data on products containing biocides were gathered by means of a market survey, exposures were estimated using a worst case scenario approach (screening, the hazard of the active components were evaluated, and a preliminary risk assessment was conducted. Methods Information on biocide-containing products was collected by on-site research, by an internet inquiry as well as research into databases and lists of active substances. Twenty active substances were selected for detailed investigation. The products containing these substances were subsequently classified by range of application; typical concentrations were derived. Potential exposures were then estimated using a worst case scenario approach according to the European Commission's Technical Guidance Document on Risk Assessment. Relevant combinations of scenarios and active substances were identified. The toxicological data for these substances were compiled in substance dossiers. For estimating risks, the margins of exposure (MOEs were determined. Results Numerous consumer products were found to contain biocides. However, it appeared that only a limited number of biocidal active substances or groups of biocidal active substances were being used. The lowest MOEs for dermal exposure or exposure by inhalation were obtained for the following scenarios and biocides: indoor pest control using sprays, stickers or evaporators (chlorpyrifos, dichlorvos and spraying of disinfectants as well as cleaning of surfaces with concentrates (hydrogen peroxide, formaldehyde, glutardialdehyde. The risk from aggregate exposure to individual biocides via different exposure scenarios was higher than the highest single exposure on average by a factor of three. From the 20 biocides assessed 10 had skin-sensitizing properties. The biocides isothiazolinone (mixture of 5-chloro

  19. Pitfall of the Strongest Cells in Static Random Access Memory Physical Unclonable Functions

    Directory of Open Access Journals (Sweden)

    Mingyang Gong

    2018-06-01

    Full Text Available Static Random Access Memory (SRAM Physical Unclonable Functions (PUFs are some of the most popular PUFs that provide a highly-secured solution for secret key storage. Given that PUF responses are noisy, the key reconstruction must use error correcting code (ECC to reduce the noise. Repetition code is widely used in resource constrained systems as it is concise and lightweight, however, research has shown that repetition codes can lead to information leakage. In this paper we found that the strongest cell distribution in a SRAM array may leak information of the responses of SRAM PUF when the repetition code is directly applied. Experimentally, on an ASIC platform with the HHGRACE 0.13 μm process, we recovered 8.3% of the measured response using the strongest cells revealed by the helper data, and we finally obtained a clone response 79% similar to weak response using the public helper data. We therefore propose Error Resistant Fuzzy Extractor (ERFE, a 4-bit error tolerant fuzzy extractor, that extracts the value of the sum of the responses as a unique key and reduces the failure rate to 1.8 × 10−8 with 256 bit entropy.

  20. Effects of two diamine biocides on the microbial community from an oil field

    International Nuclear Information System (INIS)

    Telang, A.; Voordouw, G.; Ebert, S.; Foght, J. M.; Westlake, D. W. S.

    1998-01-01

    Oil production facilities are routinely treated with biocides to control or eliminate microbes responsible for souring odor, or microbially influenced corrosion. In this study the effects of diamine biocides A and B on the microbial population from an oil field were investigated using reverse sample genome probing (RSGP), a technique designed to track multiple oil field bacteria in a single assay. RSGP studies of sessile microbial populations scraped from corrosion coupons obtained from biocide-treated oil field installations indicate dominance of Desulfovibrio species Lac6 and Eth3. Laboratory studies suggest that batchwise application of high doses (400 ppm) of biocide A is capable of killing planktonic populations of Desulfovibrio spp. Lac6 and Eth3. Batchwise application of similar doses of biocide B did not have this effect. Overall results indicate that the application of 400 ppm biocide B and 40 ppm biocide A may actually promote survival of selected Desulfovibrio spp., which may then effectively colonize available metal surfaces. 15 refs., 3 figs

  1. Image Cytometric Analysis of Algal Spores for Evaluation of Antifouling Activities of Biocidal Agents.

    Science.gov (United States)

    Il Koo, Bon; Lee, Yun-Soo; Seo, Mintae; Seok Choi, Hyung; Leng Seah, Geok; Nam, Taegu; Nam, Yoon Sung

    2017-07-31

    Chemical biocides have been widely used as marine antifouling agents, but their environmental toxicity impose regulatory restriction on their use. Although various surrogate antifouling biocides have been introduced, their comparative effectiveness has not been well investigated partly due to the difficulty of quantitative evaluation of their antifouling activity. Here we report an image cytometric method to quantitatively analyze the antifouling activities of seven commercial biocides using Ulva prolifera as a target organism, which is known to be a dominant marine species causing soft fouling. The number of spores settled on a substrate is determined through image analysis using the intrinsic fluorescence of chlorophylls in the spores. Pre-determined sets of size and shape of spores allow for the precise determination of the number of settled spores. The effects of biocide concentration and combination of different biocides on the spore settlement are examined. No significant morphological changes of Ulva spores are observed, but the amount of adhesive pad materials is appreciably decreased in the presence of biocides. It is revealed that the growth rate of Ulva is not directly correlated with the antifouling activities against the settlement of Ulva spores. This work suggests that image cytometric analysis is a very convenient, fast-processable method to directly analyze the antifouling effects of biocides and coating materials.

  2. Characterization of biocide-tolerant bacteria isolated from cheese and dairy small-medium enterprises.

    Science.gov (United States)

    Fernández Márquez, Ma Luisa; Grande Burgos, Ma José; López Aguayo, Ma Carmen; Pérez Pulido, Rubén; Gálvez, Antonio; Lucas, Rosario

    2017-04-01

    A collection of 120 bacterial isolates from small medium enterprises involved in the production of cow milk and the manufacture of goat cheese were screened for sensitivity to biocides benzalkonium chloride (BC), cetrimide (CT), hexadecylpyridinium chloride (HDP), triclosan (TC), hexachlorophene (CF) and poly-(hexamethylen guanidinium) hydrochloride (PHMG). Nineteen isolates were selected according to biocide tolerance and identified by 16S rDNA sequencing as Lactococcus sp. (6) Enterococcus sp. (1), Lactobacillus sp. (4), Bacillus sp. (1) Escherichia sp. (5), Enterobacter sp. (1) and Helicobacter sp. (1). These were further characterised regarding antimicrobial resistance phenotype and genotype. Several isolates were multiply (3 or more) tolerant to biocides or resistant to antibiotics, but only two Escherichia sp. isolates and Enterobacter sp. were multiply resistant to biocides and antibiotics. Statistical analysis of biocide tolerance and antibiotic resistance revealed significant positive correlations between different biocides and between biocides and antibiotics. The biocide tolerance genes most frequently found were qacEΔ1 and qacA/B. The sulfonamide resistance gene sul1 was found in two Escherichia sp. isolates and in Enterobacter sp., all of which also carried qacEΔ1. Beta-lactam (bla CTX-M , bla PSE ) and tetracycline resistance genes [tet(A), tet(C) and tet(D)] were detected. Efflux pump genes acrB and mdfA were found in most Gram-negative isolates. Results from the study suggest that exposure to biocides can indirectly select for antibiotic resistance. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Effects of Material Choice on Biocide Loss in Orion Water Storage Tanks

    Science.gov (United States)

    Wallace, W. T.; Wallace, S. L.; Gazda, D. B.; Lewis, J. F.

    2016-01-01

    When preparing for long-duration spaceflight missions, maintaining a safe supply of potable water is of the utmost importance. One major aspect of that is ensuring that microbial growth is minimized. Historically, this challenge has been addressed through the use of biocides. When using biocides, the choice of materials for the storage containers is important, because surface reactions can reduce biocide concentrations below their effective range. In the water storage system baselined for the Orion vehicle, the primary wetted materials are stainless steel (316 L) and a titanium alloy (Ti6Al4V). Previous testing with these materials has shown that the biocide selected for use in the system (ionic silver) will plate out rapidly upon initial wetting of the system. One potential approach for maintaining an adequate biocide concentration is to spike the water supply with high levels of biocide in an attempt to passivate the surface. To evaluate this hypothesis, samples of the wetted materials were tested individually and together to determine the relative loss of biocide under representative surface area-to-volume ratios after 24 hours. Additionally, we have analyzed the efficacy of disinfecting a system containing these materials by measuring reductions in bacterial counts in the same test conditions. Preliminary results indicate that the use of titanium, either individually or in combination with stainless steel, can result in over 95% loss of biocide, while less than 5% is lost when using stainless steel. In bacterial testing, viable organisms were recovered from samples exposed to the titanium coupons after 24 hours. By comparison, no organisms were recovered from the test vessels containing only stainless steel. These results indicate that titanium, while possessing some favorable attributes, may pose additional challenges when used in water storage tanks with ionic silver biocide.

  4. Considerations on Directive 98/8 of the European Commission - the biocide directive.

    Science.gov (United States)

    Patryn, Rafał; Jarosz, Mirosław J; Włoszczak-Szubzda, Anna; Sak, Jarosław; Pawlikowski, Jakub

    2011-01-01

    Nowadays, versatile human activity requires the development of technologies in the chemical and biological industries that ultimately enable an increase in human activity, and help create the living conditions in the domain of human civilization. Increasing this activity very frequently requires the implementation of new technologies concerning the active elimination of numerous threats and obstacles which are found in the human and natural environment. The concept of so-called biocidal products has been introduced into the European legislation as long as ten years ago, defining them as various types of 'chemical substances or microorganisms which can deter, render harmless, or exert a controlling eff ect on any harmful organism, by chemical or biological means'. They can be added to other materials (typically liquids) to protect them against biological infestation and growth. Biocidal products - due to their specificity, toxicity and composition - create a serious risk for human and animal life and health, as well as for the natural environment, it is therefore fully justified to have legal regulations concerning such biocides. Because biocidal products are intended to kill living organisms, and as such, many biocidal products pose a significant risk to human health and welfare, and have significant adverse eff ects on the natural environment. Great care is required when handling biocides and appropriate protective clothing and equipment should be used. Currently, Directive 98/8/EC is a comprehensive set of legal regulations concerning biocidal products, their specificity, principles relating to their placing on the market, and guidelines for their control. It is worth emphasizing that Directive 98/8/EC implements the clampdown on poisoning cases with biocides, the duty of which was passed to the so-called Centres of Consultation and Toxicological Information. These centres provide round-the-clock (24-hour) medical consultation and assistance in cases of

  5. Biocidal properties of maltose reduced silver nanoparticles against American foulbrood diseases pathogens.

    Science.gov (United States)

    Çulha, Mustafa; Kalay, Şaban; Sevim, Elif; Pinarbaş, Müberra; Baş, Yıldız; Akpinar, Rahşan; Karaoğlu, Şengül Alpay

    2017-12-01

    Bee disease caused by spore-forming Paenibacillus larvae and Paenibacillus alvei is a serious problem for honey production. Thus, there is an ongoing effort to find an effective agent that shows broad biocidal activity with minimal environmental hazard. In this study, the biocidal effect of maltose reduced silver nanoparticles (AgNPs) is evaluated against American foulbrood and European foulbrood pathogens. The results demonstrate that the maltose reduced AgNPs are excellent short and long-term biocides against P. larvae isolates. The long-term effect suggests that the Ag + ions are released from the AgNPs with increasing time in a controlled manner.

  6. Glass-(nAg, nCu) biocide coatings on ceramic oxide substrates.

    Science.gov (United States)

    Esteban-Tejeda, Leticia; Malpartida, Francisco; Díaz, Luis Antonio; Torrecillas, Ramón; Rojo, Fernando; Moya, José Serafín

    2012-01-01

    The present work was focused on obtaining biocide coatings constituted by a glassy soda-lime matrix containing silver or copper nanoparticles on ceramic (alumina and zirconia based) substrates. Both glassy coatings showed a high biocide activity against Gram-, Gram+ bacteria and yeast, reducing cell numbers more than three logarithms. Silver nanoparticles had a significantly higher biocide activity than copper nanoparticles, since the lixiviation levels required to reduce cell numbers more than 3 logarithms was of almost 1-2 µg/cm(2) in the case of silver nanoparticles, and 10-15 µg/cm(2) for the copper nanoparticles.

  7. Glass-(nAg, nCu biocide coatings on ceramic oxide substrates.

    Directory of Open Access Journals (Sweden)

    Leticia Esteban-Tejeda

    Full Text Available The present work was focused on obtaining biocide coatings constituted by a glassy soda-lime matrix containing silver or copper nanoparticles on ceramic (alumina and zirconia based substrates. Both glassy coatings showed a high biocide activity against Gram-, Gram+ bacteria and yeast, reducing cell numbers more than three logarithms. Silver nanoparticles had a significantly higher biocide activity than copper nanoparticles, since the lixiviation levels required to reduce cell numbers more than 3 logarithms was of almost 1-2 µg/cm(2 in the case of silver nanoparticles, and 10-15 µg/cm(2 for the copper nanoparticles.

  8. Do nonphysical punishments reduce antisocial behavior more than spanking? a comparison using the strongest previous causal evidence against spanking

    Directory of Open Access Journals (Sweden)

    Cox Ronald B

    2010-02-01

    Full Text Available Abstract Background The strongest causal evidence that customary spanking increases antisocial behavior is based on prospective studies that control statistically for initial antisocial differences. None of those studies have investigated alternative disciplinary tactics that parents could use instead of spanking, however. Further, the small effects in those studies could be artifactual due to residual confounding, reflecting child effects on the frequency of all disciplinary tactics. This study re-analyzes the strongest causal evidence against customary spanking and uses these same methods to determine whether alternative disciplinary tactics are more effective in reducing antisocial behavior. Methods This study re-analyzed a study by Straus et al.1 on spanking and antisocial behavior using a sample of 785 children who were 6 to 9 years old in the 1988 cohort of the American National Longitudinal Survey of Youth. The comprehensiveness and reliability of the covariate measure of initial antisocial behavior were varied to test for residual confounding. All analyses were repeated for grounding, privilege removal, and sending children to their room, and for psychotherapy. To account for covarying use of disciplinary tactics, the analyses were redone first for the 73% who had reported using at least one discipline tactic and second by controlling for usage of other disciplinary tactics and psychotherapy. Results The apparently adverse effect of spanking on antisocial behavior was replicated using the original trichotomous covariate for initial antisocial behavior. A similar pattern of adverse effects was shown for grounding and psychotherapy and partially for the other two disciplinary tactics. All of these effects became non-significant after controlling for latent comprehensive measures of externalizing behavior problems. Conclusions These results are consistent with residual confounding, a statistical artifact that makes all corrective actions by

  9. Organic biocides hosted in layered double hydroxides: enhancing antimicrobial activity

    Directory of Open Access Journals (Sweden)

    Cruz Alejandra Santana

    2018-03-01

    Full Text Available Samples of layered double hydroxides containing carbonates as compensating anions were prepared by the urea method. These LDHs were used as hosts of anions coming from pipemidic and nalidixic acid. XRD results confirm that these anions were hosted in the interlayer space of LDHs. Further, from 27Al NMR MAS characterization of an interaction between the brucite-like layers and anions was suggested. Then the hybrids LDHs were used as biocide of Salmonella typhi and Escherichia coli. The release profile of pipemidic and nalidixic anions from hybrid LDHs occurs for periods as long as 3.5 hours. The free-organic acid LDHs were not able to kill S. Typhi, neither E. coli. In contrast, the hybrids LDHs eliminate almost completely bacteria within short times.

  10. biological and biochemical effects of biocides and gamma radiation on pathogen attacked some horticulture crops

    International Nuclear Information System (INIS)

    Helal, I.M.M.

    2006-01-01

    the present investigation was aimed to study the possibility of formulation of some essential oils having antimicrobial activity to be used as biocides. the results of this study showed that fennel, peppermint and caraway oils were the most inhibitory effective oils against some post harvest pathogens. the used oils. were formulated as biocides using different emulsifiers with the addition of different types of fixed oils . the prepared biocides were effective for controlling the growth of the studied microorganisms in vitro and in vivo on the host plant products. also , the interaction of biocides and different doses of gamma radiation were effective for extending the shelf life of potato tubers and orange fruits during storage at room temperature for periods of 150 and 75 days, respectively. biochemical changes in potato tubers and orange fruits as a result of treatments were studied

  11. THE BIOCIDE TRIBUTYLTIN ALTERS TESTOSTERONE ESTERIFICATION IN MUD SNAILS (ILYANASSA OBSOLETA)

    Science.gov (United States)

    The Biocide Tributyltin Alters Testosterone Esterification in Mud Snails (Ilyanassa obsoleta)Meredith P. Gooding and Gerald A. LeBlanc Department of Environmental and Molecular Toxicology, North Carolina State University, Raleigh, NC 27695-7633Tributyltin (TBT...

  12. Impact of feed spacer and membrane modification by hydrophilic, bactericidal and biocidal coating on biofouling control

    KAUST Repository

    Araú jo, Paula A.; Miller, Daniel J.; Correia, Patrí cia B.; van Loosdrecht, Mark C.M.; Kruithof, Joop C.; Freeman, Benny Dean; Paul, Donald; Vrouwenvelder, Johannes S.

    2012-01-01

    surface modification agents expected to resist protein and bacterial adhesion, while copper feed spacer coatings and biocides infused in feed spacers are expected to restrict biological growth. Our studies showed that polydopamine and polydopamine-. g

  13. Genomic and transcriptomic insights into how bacteria withstand high concentrations of benzalkonium chloride biocides.

    Science.gov (United States)

    Kim, Minjae; Hatt, Janet K; Weigand, Michael R; Krishnan, Raj; Pavlostathis, Spyros G; Konstantinidis, Konstantinos T

    2018-04-13

    Benzalkonium chlorides (BAC) are commonly used biocides in broad-spectrum disinfectant solutions. How microorganisms cope with BAC exposure remains poorly understood, despite its importance for disinfection and disinfectant-induced antibiotic resistance. To provide insights into these issues, we exposed two isolates of an opportunistic pathogen, Pseudomonas aeruginosa , to increasing concentrations of BAC. One isolate was pre-adapted to BAC as it originated from a bioreactor fed with sub-inhibitory concentrations of BAC for 3 years, while the other originated from a bioreactor that received no BAC. Replicated populations of both isolates were able to survive high concentrations of BAC, up to 1200 and 1600mg/L for the non- and pre-adapted ones, respectively, exceeding typical application doses. RNA-seq analysis revealed up-regulation of efflux pump genes and decreased expression of porins related to BAC transport as well as reduced growth rate. Increased expression of spermidine (a polycation) synthase genes and mutations in the pmrB (polymyxin resistance) gene, which cause a reduction in membrane negative charge, suggested that a major adaptation to exposure to the cationic surfactant BAC was to actively stabilize cell surface charge. Collectively, these results revealed that P. aeruginosa adapts to BAC exposure by a combination of mechanisms, and provided genetic markers to monitor BAC-resistant organisms that may have applications in the practice of disinfection. Importance Benzalkonium chlorides (BAC) are widely used as biocides in disinfectant solutions, food processing lines, domestic households, and healthcare facilities. Due to their wide use and mode of action, there has been rising concern that BAC may promote antibiotic resistance. Consistently, at least 40 outbreaks have been attributed to infection by disinfectant- and antibiotic-resistant pathogens such as Pseudomonas aeruginosa However, the underlying molecular mechanisms that bacteria deal with BAC

  14. Alcohol abuse as the strongest risk factor for violent offending in patients with paranoid schizophrenia.

    Science.gov (United States)

    Kudumija Slijepcevic, Marija; Jukic, Vlado; Novalic, Darko; Zarkovic-Palijan, Tija; Milosevic, Milan; Rosenzweig, Ivana

    2014-04-01

    To determine predictive risk factors for violent offending in patients with paranoid schizophrenia in Croatia. The cross-sectional study including male in-patients with paranoid schizophrenia with (N=104) and without (N=102) history of physical violence and violent offending was conducted simultaneously in several hospitals in Croatia during one-year period (2010-2011). Data on their sociodemographic characteristics, duration of untreated illness phase (DUP), alcohol abuse, suicidal behavior, personality features, and insight into illness were collected and compared between groups. Binary logistic regression model was used to determine the predictors of violent offending. Predictors of violent offending were older age, DUP before first contact with psychiatric services, and alcohol abuse. Regression model showed that the strongest positive predictive factor was harmful alcohol use, as determined by AUDIT test (odds ratio 37.01; 95% confidence interval 5.20-263.24). Psychopathy, emotional stability, and conscientiousness were significant positive predictive factors, while extroversion, pleasantness, and intellect were significant negative predictive factors for violent offending. This study found an association between alcohol abuse and the risk for violent offending in paranoid schizophrenia. We hope that this finding will help improve public and mental health prevention strategies in this vulnerable patient group.

  15. ON POTENTIAL REPRESENTATIONS OF THE DISTRIBUTION LAW OF RARE STRONGEST EARTHQUAKES

    Directory of Open Access Journals (Sweden)

    M. V. Rodkin

    2014-01-01

    Full Text Available Assessment of long-term seismic hazard is critically dependent on the behavior of tail of the distribution function of rare strongest earthquakes. Analyses of empirical data cannot however yield the credible solution of this problem because the instrumental catalogs of earthquake are available only for a rather short time intervals, and the uncertainty in estimations of magnitude of paleoearthquakes is high. From the available data, it was possible only to propose a number of alternative models characterizing the distribution of rare strongest earthquakes. There are the following models: the model based on theGuttenberg – Richter law suggested to be valid until a maximum possible seismic event (Мmах, models of 'bend down' of earthquake recurrence curve, and the characteristic earthquakes model. We discuss these models from the general physical concepts supported by the theory of extreme values (with reference to the generalized extreme value (GEV distribution and the generalized Pareto distribution (GPD and the multiplicative cascade model of seismic regime. In terms of the multiplicative cascade model, seismic regime is treated as a large number of episodes of avalanche-type relaxation of metastable states which take place in a set of metastable sub-systems.The model of magnitude-unlimited continuation of the Guttenberg – Richter law is invalid from the physical point of view because it corresponds to an infinite mean value of seismic energy and infinite capacity of the process generating seismicity. A model of an abrupt cut of this law by a maximum possible event, Мmах is not fully logical either.A model with the 'bend-down' of earthquake recurrence curve can ensure both continuity of the distribution law and finiteness of seismic energy value. Results of studies with the use of the theory of extreme values provide a convincing support to the model of 'bend-down' of earthquakes’ recurrence curve. Moreover they testify also that the

  16. Increased persistence of antifouling paint biocides when associated with paint particles

    International Nuclear Information System (INIS)

    Thomas, K.V.; McHugh, M.; Hilton, M.; Waldock, M.

    2003-01-01

    Release of biocides associated with paint particles into marinas may increase their persistence in the environment. - Current regulatory risk assessment procedures only assess the impact of antifouling paint biocides that are released through leaching from a painted surface. Hull cleaning activities can lead to particles of antifouling paint containing biocides to enter the environment. Comparative pseudo-first order anaerobic degradation rate constants and half-lives were determined for a selection of common antifouling paint booster biocides, their degradation products, and associated with paint particles. Anaerobic half-lives of <0.5 days were calculated for chlorothalonil, dichlofluanid, and SeaNine 211, between 1 and 3 days for DCPMU and DCPU, between 14 and 35 days for diuron and CPDU, and over 226 days for GS26575 and Irgarol 1051. Increased persistence was observed when the compounds were introduced to sediments associated with antifouling paint particles. When present as antifouling paint particles, an increased half-life of 9.9 days for SeaNine 211 and 1.4 days was calculated for dichlofluanid, no significant degradation was observed for diuron. It is suspected that this is due to much of the biocide being initially bound within the matrix of the paint particle that is slowly released through dissolution processes into the sediment pore water prior to degradation. The release of booster biocides associated with paint particles into marinas has the potential to lead to their accumulation unless activities such as hull cleaning are strictly regulated

  17. Increased persistence of antifouling paint biocides when associated with paint particles

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, K.V.; McHugh, M.; Hilton, M.; Waldock, M

    2003-05-01

    Release of biocides associated with paint particles into marinas may increase their persistence in the environment. - Current regulatory risk assessment procedures only assess the impact of antifouling paint biocides that are released through leaching from a painted surface. Hull cleaning activities can lead to particles of antifouling paint containing biocides to enter the environment. Comparative pseudo-first order anaerobic degradation rate constants and half-lives were determined for a selection of common antifouling paint booster biocides, their degradation products, and associated with paint particles. Anaerobic half-lives of <0.5 days were calculated for chlorothalonil, dichlofluanid, and SeaNine 211, between 1 and 3 days for DCPMU and DCPU, between 14 and 35 days for diuron and CPDU, and over 226 days for GS26575 and Irgarol 1051. Increased persistence was observed when the compounds were introduced to sediments associated with antifouling paint particles. When present as antifouling paint particles, an increased half-life of 9.9 days for SeaNine 211 and 1.4 days was calculated for dichlofluanid, no significant degradation was observed for diuron. It is suspected that this is due to much of the biocide being initially bound within the matrix of the paint particle that is slowly released through dissolution processes into the sediment pore water prior to degradation. The release of booster biocides associated with paint particles into marinas has the potential to lead to their accumulation unless activities such as hull cleaning are strictly regulated.

  18. Significant Differences Characterise the Correlation Coefficients between Biocide and Antibiotic Susceptibility Profiles in Staphylococcus aureus.

    Science.gov (United States)

    Oggioni, Marco R; Coelho, Joana Rosado; Furi, Leonardo; Knight, Daniel R; Viti, Carlo; Orefici, Graziella; Martinez, Jose-Luis; Freitas, Ana Teresa; Coque, Teresa M; Morrissey, Ian

    2015-01-01

    There is a growing concern by regulatory authorities for the selection of antibiotic resistance caused by the use of biocidal products. We aimed to complete the detailed information on large surveys by investigating the relationship between biocide and antibiotic susceptibility profiles of a large number of Staphylococcus aureus isolates using four biocides and antibiotics commonly used in clinical practice. The minimal inhibitory concentration (MIC) for most clinically-relevant antibiotics was determined according to the standardized methodology for over 1600 clinical S. aureus isolates and compared to susceptibility profiles of benzalkonium chloride, chlorhexidine, triclosan, and sodium hypochlorite. The relationship between antibiotic and biocide susceptibility profiles was evaluated using non-linear correlations. The main outcome evidenced was an absence of any strong or moderate statistically significant correlation when susceptibilities of either triclosan or sodium hypochlorite were compared for any of the tested antibiotics. On the other hand, correlation coefficients for MICs of benzalkonium chloride and chlorhexidine were calculated above 0.4 for susceptibility to quinolones, beta-lactams, and also macrolides. Our data do not support any selective pressure for association between biocides and antibiotics resistance and furthermore do not allow for a defined risk evaluation for some of the compounds. Importantly, our data clearly indicate that there does not involve any risk of selection for antibiotic resistance for the compounds triclosan and sodium hypochlorite. These data hence infer that biocide selection for antibiotic resistance has had so far a less significant impact than feared.

  19. Annona muricata leaves have strongest cytotoxic activity against breast cancer cells

    Directory of Open Access Journals (Sweden)

    Susi Endrini

    2014-12-01

    Full Text Available Background Plant-derived herbal compounds have a long history of clinical use, better patient tolerance and acceptance. They are freely available natural compounds that can be safely used to prevent various ailments. Plants have been the basis of traditional medicine throughout the world for thousands of years and are providing mankind with new remedies. The objective of this study was to determine the cytotoxicity of soursop (Anona muricata Linn leaves and pearl grass (Hedyotis corymbosa (L. Lam. on the hormone-dependent human breast carcinoma Michigan Cancer Foundation-7 (MCF-7 cell line. Methods This study used two types of solvents (water and ethanol in the extraction process and two incubation times (24 hours and 48 hours in the MTT assays to analyze the cytotoxic effects of both plants. Results Preliminary results showed that the ethanolic extract of soursop leaves (SE displayed cytotoxic effects against MCF-7 on 24- and 48-hour incubation times with IC50 values of 88.788 ìg/ml and 14.678 mg/ml, respectively. Ethanolic pearl grass extract (PE showed similar results, with IC50 values of 65.011 mg/ml on 24-hour incubation time and 52.329 mg/ml on 48-hour incubation time against MCF-7 cell line. However, the water extract of both plants displayed lower cytotoxic effect against MCF-7 cell line. Conclusion The ethanolic extract of both plants displayed cytotoxic effect against MCF-7. Soursop (Anona muricata Linn leaves have the strongest cytotoxic activity against MCF-7 breast cancer cell line.

  20. Annona muricata leaves have strongest cytotoxic activity against breast cancer cells

    Directory of Open Access Journals (Sweden)

    Susi Endrini

    2015-12-01

    Full Text Available BACKGROUND Plant-derived herbal compounds have a long history of clinical use, better patient tolerance and acceptance. They are freely available natural compounds that can be safely used to prevent various ailments. Plants have been the basis of traditional medicine throughout the world for thousands of years and are providing mankind with new remedies. The objective of this study was to determine the cytotoxicity of soursop (Anona muricata Linn leaves and pearl grass (Hedyotis corymbosa (L. Lam. on the hormone-dependent human breast carcinoma Michigan Cancer Foundation-7 (MCF-7 cell line. METHODS This study used two types of solvents (water and ethanol in the extraction process and two incubation times (24 hours and 48 hours in the MTT assays to analyze the cytotoxic effects of both plants. RESULTS Preliminary results showed that the ethanolic extract of soursop leaves (SE displayed cytotoxic effects against MCF-7 on 24- and 48-hour incubation times with IC50 values of 88.788 μg/ml and 14.678 μg/ml, respectively. Ethanolic pearl grass extract (PE showed similar results, with IC50 values of 65.011 μg/ ml on 24-hour incubation time and 52.329 μg/ml on 48-hour incubation time against MCF-7 cell line. However, the water extract of both plants displayed lower cytotoxic effect against MCF-7 cell line. CONCLUSION The ethanolic extract of both plants displayed cytotoxic effect against MCF-7. Soursop (Anona muricata Linn leaves have the strongest cytotoxic activity against MCF-7 breast cancer cell line.

  1. Formulation of Biocides Increases Antimicrobial Potency and Mitigates the Enrichment of Nonsusceptible Bacteria in Multispecies Biofilms

    Science.gov (United States)

    Forbes, Sarah; Cowley, Nicola; Mistry, Hitesh; Amézquita, Alejandro

    2017-01-01

    ABSTRACT The current investigation aimed to generate data to inform the development of risk assessments of biocide usage. Stabilized domestic drain biofilm microcosms were exposed daily over 6 months to increasing concentrations (0.01% to 1%) of the biocide benzalkonium chloride (BAC) in a simple aqueous solution (BAC-s) or in a complex formulation (BAC-f) representative of a domestic cleaning agent. Biofilms were analyzed by culture, differentiating by bacterial functional group and by BAC or antibiotic susceptibility. Bacterial isolates were identified by 16S rRNA sequencing, and changes in biofilm composition were assessed by high-throughput sequencing. Exposure to BAC-f resulted in significantly larger reductions in levels of viable bacteria than exposure to BAC-s, while bacterial diversity greatly decreased during exposure to both BAC-s and BAC-f, as evidenced by sequencing and viable counts. Increases in the abundance of bacteria exhibiting reduced antibiotic or BAC susceptibility following exposure to BAC at 0.1% were significantly greater for BAC-s than BAC-f. Bacteria with reduced BAC and antibiotic susceptibility were generally suppressed by higher BAC concentrations, and formulation significantly enhanced this effect. Significant decreases in the antimicrobial susceptibility of bacteria isolated from the systems before and after long-term BAC exposure were not detected. In summary, dose-dependent suppression of bacterial viability by BAC was enhanced by formulation. Biocide exposure decreased bacterial diversity and transiently enriched populations of organisms with lower antimicrobial susceptibility, and the effects were subsequently suppressed by exposure to 1% BAC-f, the concentration most closely reflecting deployment in formulated products. IMPORTANCE Assessment of the risks of biocide use has been based mainly on the exposure of axenic cultures of bacteria to biocides in simple aqueous solutions. The current investigation aimed to assess the

  2. Comparison of biocides for disinfection treatment of open recirculating cooling circuits

    International Nuclear Information System (INIS)

    Soreau, Sylvie; Prisset, Frederic; Carvajal, Nathalie

    2012-09-01

    Open recirculating cooling circuits of nuclear power plants are likely to face pathogenic proliferations like Legionella and amoebae (Naegleria fowleri). To reduce such risks, biocide treatments are usually implemented. However, the selection of a treatment is never easy due to the large size of the cooling circuits. Indeed, the range of treatment options is limited due to potential health or environmental impacts of chemicals in case of chemical treatments or because of the technical difficulties to implement treatment units appropriate to the size of the cooling circuits in case of physical treatments. In the aim of finding the best compromise between efficacy, nature and quantity of chemical releases and industrial feasibility, several biocide treatments were compared at lab and pilot scale using semi-industrial pilot plants simulating recirculating cooling circuit of a nuclear power plant. These pilots were fed with river water or pre-treated water (lime softening or clari-flocculation). They were equipped with materials and surfaces representative of those found on a full-scale plant. These pilots operated at summer temperatures favoring microbial growth. Three industrial biocides were compared: chlorine, monochloramine and chlorine dioxide. The results indicate that the transit in the cooling system strongly affects the consumption of biocides and therefore their efficacy, the quantity of biocide needed and chemical releases so that the ranking of treatments defined on the basis of laboratory tests can be strongly modified. The results show different areas of consumption along the process line depending on biocides and highlight the significant role of the cooling tower. The behavior of biocides in the different compartments of the circuit (cooling tower, condenser, basins) is described and the consequences on pathogenic micro-organisms removal in bio-films and on chemical releases are considered as function of the studied biocide. Moreover, the influence of

  3. Biocides in hydraulic fracturing: hazard and vulnerability with respect to potential groundwater pollution

    Science.gov (United States)

    Worrall, Fred; Wilson, Miles; Davies, Richard

    2016-04-01

    Biocides are one possible chemical additive to frack fluids and their role is to control bacterial growth. Bacterial growth might lead to biofilm build up; and acid sulfide species and hydrogen sulfide (H2S) production: biofilm build up may reduce formation permeability and hinder gas extraction. Kahrilas et al. (2014) published a review of common biocides used in fracking in the USA. The biocides assessed in the review were the sixteen most commonly used in the USA, based on the hydraulic fracturing chemical registry Frac Focus (Frac Focus, 2015). However, the review of Kahrilas et al. (2014) contained no data or observations and so the objective of this study was to consider whether biocides proposed for use in hydrofacturing could be a threat to English groundwater. The study considered all groundwater samples analysed for biocides in English groundwater between 2005 and 2014. The monitoring records were compared to: records of application (both amount and area); and chemical and molecular data for the biocides. The study did not use traditional adsorption and degradation data as these parameters are to prone to variability and are not pure molecular parameters. The study then used the approach of Worrall and Thomsen (2004) to consider the hazard represented by proposed frack biocides and the approach of Worrall and Kolpin (2003) to consider the vulnerability of the areas of potential shale gas exploitation. The study showed that of the 113 biocides tested for in English groundwaters in the decade 2005 - 2014 that 95 were detected above 0.1 g/l . Of these 95, 41 were compounds that were not recorded as being applied during the period of record and the detection of these 41 compounds did not decline over the 10 year period which implies very long residence times and that once compounds do pollute an aquifer then they will be a persistent problem. Furthermore, the solubility of the range of biocides used in frack fluids would imply a potentially higher hazard

  4. Inhalational and dermal exposures during spray application of biocides.

    Science.gov (United States)

    Berger-Preiss, Edith; Boehncke, Andrea; Könnecker, Gustav; Mangelsdorf, Inge; Holthenrich, Dagmar; Koch, Wolfgang

    2005-01-01

    Data on inhalational and potential dermal exposures during spray application of liquid biocidal products were generated. On the one hand, model experiments with different spraying devices using fluorescent tracers were carried out to investigate the influence of parameters relevant to the exposure (e.g. spraying equipment, nozzle size, direction of application). On the other hand, measurements were performed at selected workplaces (during disinfection operations in food and feed areas; pest control operations for private, public and veterinary hygiene; wood protection and antifouling applications) after application of biocidal products such as Empire 20, Responsar SC, Omexan-forte, Actellic, Perma-forte; Fendona SC, Pyrethrum mist; CBM 8, Aldekol Des 03, TAD CID, Basileum, Basilit. The measurements taken in the model rooms demonstrated dependence of the inhalation exposure on the type of spraying device used, in the following order: "spraying with low pressure" < "airless spraying" < "fogging" indicating that the particle diameter of the released spray droplets is the most important parameter. In addition inhalation exposure was lowest when the spraying direction was downward. Also for the potential dermal exposure, the spraying direction was of particular importance: overhead spraying caused the highest contamination of body surfaces. The data of inhalational and potential dermal exposures gained through workplace measurements showed considerable variation. During spraying procedures with low-pressure equipments, dose rates of active substances inhaled by the operators ranged from 7 to 230 microg active substance (a.s.)/h. An increase in inhaled dose rates (6-33 mg a.s./h) was observed after use of high application volumes/time unit during wood protection applications indoors. Spraying in the veterinary sector using medium-pressure sprayers led to inhaled dose rates between 2 and 24mga.s./h. The highest inhaled dose rates were measured during fogging (114 mg a

  5. Biocide and antibiotic susceptibility of Salmonella isolates obtained before and after cleaning at six Danish pig slaughterhouses

    DEFF Research Database (Denmark)

    Gantzhorn, Mette Rørbæk; Pedersen, Karl; Olsen, John Elmerdahl

    2014-01-01

    between susceptibilities to biocides and antibiotics, and to examine if cleaning and disinfection select isolates with changed susceptibility toward biocides or antibiotics.Salmonella sp. was isolated from the environment in Danish pig slaughterhouses before and after cleaning and disinfection....... The susceptibility toward three different biocides, triclosan and two commercial disinfection products: Desinfect Maxi, a quaternary ammonium compound, and Incimaxx DES, an acetic compound, was determined. We found no resistance toward the biocides tested, but we did find that isolates obtained after cleaning had...

  6. Loading and release mechanisms of a biocide in polystyrene-block-poly(acrylic acid) block copolymer micelles.

    Science.gov (United States)

    Vyhnalkova, Renata; Eisenberg, Adi; van de Ven, Theo G M

    2008-07-24

    The kinetics of loading of polystyrene197-block-poly(acrylic acid)47 (PS197-b-PAA47) micelles, suspended in water, with thiocyanomethylthiobenzothiazole biocide and its subsequent release were investigated. Loading of the micelles was found to be a two-step process. First, the surface of the PS core of the micelles is saturated with biocide, with a rate determined by the transfer of solid biocide to micelles during transient micelle-biocide contacts. Next, the biocide penetrates as a front into the micelles, lowering the Tg in the process (non-Fickian case II diffusion). The slow rate of release is governed by the height of the energy barrier that a biocide molecule must overcome to pass from PS into water, resulting in a uniform biocide concentration within the micelle, until Tg is increased to the point that diffusion inside the micelles becomes very slow. Maximum loading of biocide into micelles is approximately 30% (w/w) and is achieved in 1 h. From partition experiments, it can be concluded that the biocide has a similar preference for polystyrene as for ethylbenzene over water, implying that the maximum loading is governed by thermodynamics.

  7. The strongest magnetic barrier in the DIII-D tokamak and comparison with the ASDEX UG

    Science.gov (United States)

    Ali, Halima; Punjabi, Alkesh

    2013-05-01

    (2010)] based on continued fraction decomposition of the rotational transform labeling the barriers for selecting and identifying the strongest noble irrational barrier is used. The results are compared and contrasted with our previous results on the ASDEX UG. About six times stronger a barrier can be built in the DIII-D than in the ASDEX UG. High magnetic shear near the separatrix in the DIII-D is inferred as the possible cause of this. Implications of this for the DIII-D and the International Thermonuclear Experimental Reactor (ITER) are discussed.

  8. Education is the strongest socio-economic predictor of smoking in pregnancy.

    Science.gov (United States)

    Härkönen, Juho; Lindberg, Matti; Karlsson, Linnea; Karlsson, Hasse; Scheinin, Noora M

    2018-06-01

    To investigate socio-economic disparities in smoking in pregnancy (SIP) by the mother's education, occupational class and current economic conditions. Cross-sectional analysis with linked survey and register data. South-western Finland. A total of 2667 pregnant women [70% of the original sample (n = 3808)] from FinnBrain, a prospective pregnancy cohort study. The outcome was smoking during the first pregnancy trimester, measured from the Finnish Medical Birth Register. Education and occupational class were linked from population registers. Income support recipiency and subjective economic wellbeing were questionnaire-based measures of current economic conditions. These were adjusted for age, partnership status, residential area type, parental separation, parity, childhood socio-economic background, childhood adversities (the Trauma and Distressing Events During Childhood scale) and antenatal stress (Edinburgh Postnatal Depression Scale). Logistic regressions and attributable fractions (AF) were estimated. Mother's education was the strongest socio-economic predictor of SIP. Compared with university education, adjusted odds ratios (aORs) of SIP were: 2.2 [95% confidence interval (CI) = 1.2-3.9; P = 0.011] for tertiary vocational education, 4.4 (95% CI = 2.1-9.0; P < 0.001) for combined general and vocational secondary education, 2.9 (95% CI = 1.4-6.1; P = 0.006) for general secondary education, 9.5 (95% CI 5.0-18.2; P < 0.001) for vocational secondary education and 14.4 (95% CI = 6.3-33.0; P < 0.001) for compulsory schooling. The total AF of education was 0.5. Adjusted for the other variables, occupational class and subjective economic wellbeing did not predict SIP. Income support recipiency was associated positively with SIP (aOR = 1.8; 95% CI = 1.1-3.1; P = 0.022). Antenatal stress predicted SIP (aOR = 2.0; 95% CI = 1.4-2.8; P < 0.001), but did not attenuate its socio-economic disparities. In Finland, socio-economic disparities in

  9. Emission Scenario Document for Biocides Emission scenarios for all 23 product types of the Biocidal Products Directive (EU Directive 98/8/EC)

    NARCIS (Netherlands)

    Poel P van der; Bakker J; CSR

    2002-01-01

    Dit rapport geeft een overzicht van de beschikbare emissiescenario's voor niet-landbouwbestrijdingsmiddelen voor alle 23 productgroepen uit de biocide richtlijn (EU Richtlijn 98/8/EC). Het betreft scenario's die reeds in USES 3.0 zijn opgenomen, alsmede scenario's die

  10. Emission Scenario Document for Biocides Emission scenarios for all 23 product types of the Biocidal Products Directive (EU Directive 98/8/EC)

    NARCIS (Netherlands)

    Poel P van der; Bakker J; CSR

    2002-01-01

    This report presents an overview of all available emission scenarios for all 23 product types of biocides according to EU Directive 98/8/EC. The scenarios presented are already present in USES 3.0 or have been reported by RIVM or within the scope of the project "Gathering, review and development of

  11. Selection of an Alternate Biocide for the ISS Internal Thermal Control System Coolant, Phase 2

    Science.gov (United States)

    Wilson, Mark E.; Cole, Harold; Weir, Natalee; Oehler, Bill; Steele, John; Varsik, Jerry; Lukens, Clark

    2004-01-01

    The ISS (International Space Station) ITCS (Internal Thermal Control System) includes two internal coolant loops that utilize an aqueous based coolant for heat transfer. A silver salt biocide had previously been utilized as an additive in the coolant formulation to control the growth and proliferation of microorganisms within the coolant loops. Ground-based and in-flight testing demonstrated that the silver salt was rapidly depleted, and did not act as an effective long-term biocide. Efforts to select an optimal alternate biocide for the ITCS coolant application have been underway and are now in the final stages. An extensive evaluation of biocides was conducted to down-select to several candidates for test trials and was reported on previously. Criteria for that down-select included: the need for safe, non-intrusive implementation and operation in a functioning system; the ability to control existing planktonic and biofilm residing microorganisms; a negligible impact on system-wetted materials of construction; and a negligible reactivity with existing coolant additives. Candidate testing to provide data for the selection of an optimal alternate biocide is now in the final stages. That testing has included rapid biocide effectiveness screening using Biolog MT2 plates to determine minimum inhibitory concentration (amount that will inhibit visible growth of microorganisms), time kill studies to determine the exposure time required to completely eliminate organism growth, materials compatibility exposure evaluations, coolant compatibility studies, and bench-top simulated coolant testing. This paper reports the current status of the effort to select an alternate biocide for the ISS ITCS coolant. The results of various test results to select the optimal candidate are presented.

  12. Cytotoxic effects of air freshener biocides in lung epithelial cells.

    Science.gov (United States)

    Kwon, Jung-Taek; Lee, Mimi; Seo, Gun-Baek; Kim, Hyun-Mi; Shim, Ilseob; Lee, Doo-Hee; Kim, Taksoo; Seo, Jung Kwan; Kim, Pilje; Choi, Kyunghee

    2013-09-01

    This study evaluated the cytotoxicity of mixtures of citral (CTR) and either benzisothiazolinone (BIT, Mix-CTR-BIT) or triclosan (TCS, Mix-CTR-TCS) in human A549 lung epithelial cells. We investigated the effects of various mix ratios of these common air freshener ingredients on cell viability, cell proliferation, reactive oxygen species (ROS) generation, and DNA damage. Mix-CTR-BIT and Mix-CTR-TCS significantly decreased the viability of lung epithelial cells and inhibited cell growth in a dose-dependent manner. In addition, both mixtures increased ROS generation, compared to that observed in control cells. In particular, cell viability, growth, and morphology were affected upon increase in the proportion of BIT or TCS in the mixture. However, comet analysis showed that treatment of cells with Mix-CTR-BIT or Mix-CTR-TCS did not increase DNA damage. Taken together, these data suggested that increasing the content of biocides in air fresheners might induce cytotoxicity, and that screening these compounds using lung epithelial cells may contribute to hazard assessment.

  13. One-pot facile green synthesis of biocidal silver nanoparticles

    Science.gov (United States)

    Nudrat Hazarika, Shabiha; Gupta, Kuldeep; Shamin, Khan Naseem Ahmed Mohammed; Bhardwaj, Pushpender; Boruah, Ratan; Yadav, Kamlesh K.; Naglot, Ashok; Deb, P.; Mandal, M.; Doley, Robin; Veer, Vijay; Baruah, Indra; Namsa, Nima D.

    2016-07-01

    The plant root extract mediated green synthesis method produces monodispersed spherical shape silver nanoparticles (AgNPs) with a size range of 15-30 nm as analyzed by atomic force and transmission electron microscopy. The material showed potent antibacterial and antifungal properties. Synthesized AgNPs display a characteristic surface plasmon resonance peak at 420 nm in UV-Vis spectroscopy. X-ray diffractometer analysis revealed the crystalline and face-centered cubic geometry of in situ prepared AgNPs. Agar well diffusion and a colony forming unit assay demonstrated the potent biocidal activity of AgNPs against Staphylococcus aureus, Escherichia coli, Bacillus subtilis, Klebsiella pneumoniae, Pseudomonas diminuta and Mycobacterium smegmatis. Intriguingly, the phytosynthesized AgNPs exhibited activity against pathogenic fungi, namely Trichophyton rubrum, Aspergillus versicolor and Candida albicans. Scanning electron microscopy observations indicated morphological changes in the bacterial cells incubated with silver nanoparticles. The genomic DNA isolated from the bacteria was incubated with an increasing concentration of AgNPs and the replication fidelity of 16S rDNA was observed by performing 18 and 35 cycles PCR. The replication efficiency of small (600 bp) and large (1500 bp) DNA fragments in the presence of AgNPs were compromised in a dose-dependent manner. The results suggest that the Thalictrum foliolosum root extract mediated synthesis of AgNPs could be used as a promising antimicrobial agent against clinical pathogens.

  14. Nanosilver against fungi. Silver nanoparticles as an effective biocidal factor.

    Science.gov (United States)

    Pulit, Jolanta; Banach, Marcin; Szczygłowska, Renata; Bryk, Mirosław

    2013-01-01

    The work presents a method of obtaining an aqueous raspberry extract as well as its physicochemical and analytical characteristics. The paper also contains a description of the method of preparation of nanosilver suspensions based on this extract. The raspberry extract served as a source of phenolic compounds which acted as both reducing and stabilizing agents. Suspensions of silver nanoparticles were obtained with the use of chemical reduction method. The silver ions concentration, pH value and temperature of samples incubation were independent variables. The next step of the research was to measure the antifungal activity of the received silver nanoparticles as well as to perform a mycological efficacy resistance analysis of the tested preparations in relation to different concentrations of nanostructured silver. Tests were conducted in compliance with the Eucast guidelines. The results of microbiological study of (the samples') biocidal effect against Cladosporium cladosporoides and Aspergillus niger are described. It was found that using nanosilver suspension at the concentration of 50 ppm inhibited the growth of Cladosporium cladosporoides and Aspergillus niger by 90% and 70%, respectively.

  15. Searching for “Environmentally-Benign” Antifouling Biocides

    Directory of Open Access Journals (Sweden)

    Yan Ting Cui

    2014-05-01

    Full Text Available As the result of the ecological impacts from the use of tributyltins (TBT in shipping, environmental legislation for the registration of chemicals for use in the environment has grown to a monumental challenge requiring product dossiers to include information on the environmental fate and behavior of any chemicals. Specifically, persistence, bioaccumulation and toxicity, collectively known as PBT, are properties of concern in the assessment of chemicals. However, existing measurements of PBT properties are a cumbersome and expensive process, and thus not applied in the early stages of the product discovery and development. Inexpensive methods for preliminary PBT screening would minimize risks arising with the subsequent registration of products. In this article, we evaluated the PBT properties of compounds reported to possess anti-fouling properties using QSAR (quantitative structure-activity relationship prediction programs such as BIOWIN™ (a biodegradation probability program, KOWWIN™ (log octanol-water partition coefficient calculation program and ECOSAR™ (Ecological Structure Activity Relationship Programme. The analyses identified some small (Mr < 400 synthetic and natural products as potential candidates for environmentally benign biocides. We aim to demonstrate that while these methods of estimation have limitations, when applied with discretion, they are powerful tools useful in the early stages of research for compound selection for further development as anti-foulants.

  16. Fabrication of polypropylene/silver nanocomposites for biocidal applications

    Energy Technology Data Exchange (ETDEWEB)

    Oliani, Washington Luiz, E-mail: washoliani@usp.br [Nuclear and Energy Research Institute, IPEN-CNEN/SP, Av. Prof. Lineu Prestes, 2242 – Cidade Universitária – CEP, 05508-000 São Paulo (Brazil); Parra, Duclerc Fernandes; Komatsu, Luiz Gustavo Hiroki [Nuclear and Energy Research Institute, IPEN-CNEN/SP, Av. Prof. Lineu Prestes, 2242 – Cidade Universitária – CEP, 05508-000 São Paulo (Brazil); Lincopan, Nilton [Department of Microbiology, Institute of Biomedical Sciences, University of Sao Paulo, 05508-000, São Paulo (Brazil); Department of Clinical Analysis, School of Pharmacy, University of São Paulo, 05508-000, São Paulo (Brazil); Rangari, Vijaya Kumar [Department of Materials Science and Engineering, Tuskegee University, AL 36088 (United States); Lugao, Ademar Benevolo [Nuclear and Energy Research Institute, IPEN-CNEN/SP, Av. Prof. Lineu Prestes, 2242 – Cidade Universitária – CEP, 05508-000 São Paulo (Brazil)

    2017-06-01

    This paper presents a study on biocidal effect of polymer nanocomposite films of gamma irradiated polypropylene (PP) and silver nanoparticles. The modified polypropylene was obtained from isotactic polypropylene (iPP) in pellets form by irradiation with gamma rays in the presence of acetylene. A new morphology with long chain branching of PP and distinct rheology is obtained by this process. The blend of 50/50 wt% neat PP and PP modified by gamma radiation were further mixed using a twin screw extruder. The AgNPs were infused into this polymer blend at different concentrations of: 0.1%; 0.25%; 0.5%; 1.0%; 1.0% (PVP), 2.0% and 4.0% by wt%. These polymer nanocomposites were characterized by Raman spectroscopy, scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), thermogravimetric analysis (TG), differential scanning calorimetry (DSC), X-ray diffraction (XRD), transmission electron microscopy (TEM), cytotoxicity test and Kirby-Bauer disk diffusion techniques. The bactericidal effect of Pseudomonas aeruginosa (P. aeruginosa) and Staphylococcus aureus (S. aureus) were assessed in detail. - Highlights: • PP film was obtained from iPP in pellets form by γ rays with acetylene and AgNPs • Bactericidal effect of P aeruginosa and S aureus were assessed.

  17. Pulsar discoveries by volunteer distributed computing and the strongest continuous gravitational wave signal

    Science.gov (United States)

    Knispel, Benjamin

    2011-07-01

    Neutron stars are the endpoints of stellar evolution and one of the most compact forms of matter in the universe. They can be observed as radio pulsars and are promising sources for the emission of continuous gravitational waves. Discovering new radio pulsars in tight binary orbits offers the opportunity to conduct very high precision tests of General Relativity and to further our understanding of neutron star structure and matter at super-nuclear densities. The direct detection of gravitational waves would validate Einstein's theory of Relativity and open a new window to the universe by offering a novel astronomical tool. This thesis addresses both of these scientific fields: the first fully coherent search for radio pulsars in tight, circular orbits has been planned, set up and conducted in the course of this thesis. Two unusual radio pulsars, one of them in a binary system, have been discovered. The other half of this thesis is concerned with the simulation of the Galactic neutron star population to predict their emission of continuous gravitational waves. First realistic statistical upper limits on the strongest continuous gravitational-wave signal and detection predictions for realistic all-sky blind searches have been obtained. The data from a large-scale pulsar survey with the 305-m Arecibo radio telescope were searched for signals from radio pulsars in binary orbits. The massive amount of computational work was done on hundreds of thousands of computers volunteered by members of the general public through the distributed computing project Einstein@Home. The newly developed analysis pipeline searched for pulsar spin frequencies below 250 Hz and for orbital periods as short as 11 min. The structure of the search pipeline consisting of data preparation, data analysis, result post-processing, and set-up of the pipeline components is presented in detail. The first radio pulsar, discovered with this search, PSR J2007+2722, is an isolated radio pulsar, likely from

  18. In vitro activity of seven hospital biocides against Mycobacterium abscessus: Implications for patients with cystic fibrosis

    Directory of Open Access Journals (Sweden)

    Steven Caskey

    2018-01-01

    Full Text Available Background: Mycobacterium abscessus pulmonary infection has recently emerged as a significant pathogen in patients with cystic fibrosis (CF and is associated with significant morbidity and accelerated pulmonary decline. There is a paucity of data describing the activity of hospital biocides against this organism. Methods: M. abscessus isolates (n = 13 were recovered from CF and non-CF respiratory specimens. Seven commonly employed hospital biocides with generic ingredients as follows: acetone, propan-2-ol, diethylene glycol, 5-chloro-2-methyl-4-isothiazolin-3-one and 2-methyl-4-isothiazolin-3-one, chlorine dioxide, 4% chlorhexidine, alcohol, and disodium carbonate, compound with hydrogen peroxide, 10% sodium hypochlorite were assayed for their biocidal activity against M. abscessus. Fresh cultures of M. abscessus were exposed to biocide in liquid medium as per manufacturers' instruction and were immediately plated following the completion of the contact period. The mean concentration of M. abscessus plated was 9.82 × 106 colony-forming units (range: 1.63 × 105–1.12 × 108. In addition, the remaining bacteria/biocide solution was enriched nonselectively in Mueller Hinton broth (37°C/1 week and then plated. Results: All M. abscessus isolates survived in alkyl dimethyl benzyl ammonium chloride, 5-chloro-2-methyl-2H-isothiazol-3-one (EC No. 247-500-7 and 2-methyl-2H-isothiazol-3-one, 4% Chlorhexidine™, O-phenylphenol and Sodium Lauryl Sulfate™ and disodium carbonate, compound with hydrogen peroxide. One out of 13 M. abscessus cultures was killed by Chlorine Dioxide™ and one by Sodium Dichloroisocyanurate™, representing a 5-log kill. Two isolates were killed by Alcohol™ again representing a 5 log kill. Following enrichment, O-phenylphenol and Sodium Lauryl Sulfate™ showed the greatest biocidal activity with 11/13 isolates, whereas 2/13 cultures were killed by sodium dichloroisocyanurate™. All other biocide/culture combinations

  19. In vitro activity of seven hospital biocides against Mycobacterium abscessus: Implications for patients with cystic fibrosis.

    Science.gov (United States)

    Caskey, Steven; Moore, John E; Rendall, Jacqueline C

    2018-01-01

    Mycobacterium abscessus pulmonary infection has recently emerged as a significant pathogen in patients with cystic fibrosis (CF) and is associated with significant morbidity and accelerated pulmonary decline. There is a paucity of data describing the activity of hospital biocides against this organism. M. abscessus isolates (n = 13) were recovered from CF and non-CF respiratory specimens. Seven commonly employed hospital biocides with generic ingredients as follows: acetone, propan-2-ol, diethylene glycol, 5-chloro-2-methyl-4-isothiazolin-3-one and 2-methyl-4-isothiazolin-3-one, chlorine dioxide, 4% chlorhexidine, alcohol, and disodium carbonate, compound with hydrogen peroxide, 10% sodium hypochlorite were assayed for their biocidal activity against M. abscessus. Fresh cultures of M. abscessus were exposed to biocide in liquid medium as per manufacturers' instruction and were immediately plated following the completion of the contact period. The mean concentration of M. abscessus plated was 9.82 × 10 6 colony-forming units (range: 1.63 × 10 5 -1.12 × 10 8 ). In addition, the remaining bacteria/biocide solution was enriched nonselectively in Mueller Hinton broth (37°C/1 week) and then plated. All M. abscessus isolates survived in alkyl dimethyl benzyl ammonium chloride, 5-chloro-2-methyl-2H-isothiazol-3-one (EC No. 247-500-7) and 2-methyl-2H-isothiazol-3-one, 4% Chlorhexidine™, O-phenylphenol and Sodium Lauryl Sulfate™ and disodium carbonate, compound with hydrogen peroxide. One out of 13 M. abscessus cultures was killed by Chlorine Dioxide™ and one by Sodium Dichloroisocyanurate™, representing a 5-log kill. Two isolates were killed by Alcohol™ again representing a 5 log kill. Following enrichment, O-phenylphenol and Sodium Lauryl Sulfate™ showed the greatest biocidal activity with 11/13 isolates, whereas 2/13 cultures were killed by sodium dichloroisocyanurate™. All other biocide/culture combinations yielded growth. These data indicate that M

  20. Elaboration of a concept for the cumulative environmental exposure assessment of biocides

    Energy Technology Data Exchange (ETDEWEB)

    Gross, Rita; Bunke, Dirk; Moch, Katja [Oeko-Institut e.V. - Institut fuer Angewandte Oekologie e.V., Freiburg im Breisgau (Germany); Gartiser, Stefan [Hydrotox GmbH, Freiburg im Breisgau (Germany)

    2011-12-15

    Article 10(1) of the EU Biocidal Products Directive 98/8/EC (BPD) requires that for the inclusion of an active substance in Annex I, Annex IA or IB, cumulation effects from the use of biocidal products containing the same active substance shall be taken into account, where relevant. The study proves the feasibility of a technical realisation of Article 10(1) of the BPD and elaborates a first concept for the cumulative environmental exposure assessment of biocides. Existing requirements concerning cumulative assessments in other regulatory frameworks have been evaluated and their applicability for biocides has been examined. Technical terms and definitions used in this context were documented with the aim to harmonise terminology with other frameworks and to set up a precise definition within the BPD. Furthermore, application conditions of biocidal products have been analysed to find out for which cumulative exposure assessments may be relevant. Different parameters were identified which might serve as indicators for the relevance of cumulative exposure assessments. These indicators were then integrated in a flow chart by means of which the relevance of cumulative exposure assessments can be checked. Finally, proposals for the technical performance of cumulative exposure assessments within the Review Programme have been elaborated with the aim to bring the results of the project into the upcoming development and harmonization processes on EU level. (orig.)

  1. Evaluation of the Biocidal Efficacy of Different Forms of Silver Against Cupriavidus (formerly Wautersia) Species Bacteria

    Science.gov (United States)

    Gazda, Daniel B.; Schultz, John R.; Wong, Wing; Algate, Michelle T.; Bryant, Becky; Castro, Victoria A.

    2009-01-01

    Contingency Water Containers (CWCs) are used to store potable and technical water that is transferred to the International Space Station (ISS) from the Shuttle orbiter vehicles. When CWCs are filled, water from the orbiter galley is passed through an ion exchange/activated carbon cartridge that removes the residual iodine biocide used on Shuttle before silver biocide is added. Removal of iodine and addition of silver is necessary to inhibit microbial growth inside CWCs and maintain compatibility with the water systems in the Russian segment of ISS. As part of nominal water transfer activities, crewmembers collect samples from several CWCs for postflight analysis. Results from the analysis of water transfer samples collected during the docked phases of STS-118/13A.1 and STS-120/10A showed that several of the CWCs contained up to 10(exp 4) CFU/mL of bacteria despite the fact that the silver concentrations in the CWCs were within acceptable limits. The samples contained pure cultures of a single bacteria, a Cupriavidus (formerly Wautersia) species that has been shown to be resistant to metallic biocides. As part of the investigation into the cause and remediation of the bacterial contamination in these CWCs, ground studies were initiated to evaluate the resistance of the Cupriavidus species to the silver biocides used on ISS and to determine the minimum effective concentration for the different forms of silver present in the biocides. The initial findings from those experiments are discussed herein.

  2. Controlling the invasive diatom Didymosphenia geminata: an ecotoxicity assessment of four potential biocides.

    Science.gov (United States)

    Jellyman, P G; Clearwater, S J; Clayton, J S; Kilroy, C; Blair, N; Hickey, C W; Biggs, B J F

    2011-07-01

    In 2004, an invasive mat-forming freshwater diatom, Didymosphenia geminata (didymo), was found in New Zealand causing concern with regard to potential consequences for local freshwater ecosystems. A four-stage research program was initiated to identify methods to control D. geminata. This article reports the results of Stage 2, in which four potential control compounds [Gemex™ (a chelated copper formulation), EDTA, Hydrothol®191, and Organic Interceptor™ (a pine oil formulation)] selected in Stage 1 were evaluated for their biocidal efficacy on D. geminata and effects on non-target organisms using both artificial stream and laboratory trials. Artificial stream trials evaluated the mortality rates of D. geminata and fishes to three concentrations of the four biocides, whereas laboratory toxicity trials tested the response of green alga and cladocera to a range of biocide concentrations and exposure times. In artificial stream trials, Gemex and Organic Interceptor were the most effective biocides against D. geminata for a number of measured indices; however, exposure of fishes to Organic Interceptor resulted in high mortality rates. Laboratory toxicity testing indicated that Gemex might negatively affect sensitive stream invertebrates, based on the cladoceran sensitivity at the proposed river control dose. A decision support matrix evaluated the four biocides based on nine criteria stipulated by river stakeholders (effectiveness, non-target species impacts, stalk removal, degradation profile, risks to health and safety, ease of application, neutralization potential, cost, and local regulatory requirements) and Gemex was identified as the product warranting further refinement prior to an in-river trial.

  3. Emission of biocides from treated materials: test procedures for water and air.

    Science.gov (United States)

    Schoknecht, Ute; Wegner, Robby; Horn, Wolfgang; Jann, Oliver

    2003-01-01

    Methods for the determination of biocide emissions from treated materials into water and air were developed and tested in order to support a comparative ecological assessment of biocidal products. Leaching tests, experiments with simulated rain, extraction cleaning of carpets and emission chamber tests were performed with a series of treated materials. The experiments focused on the effect of changes in the procedure as well as characteristics of the specimens and demonstrate the suitability of the proposed methods for biocides of different product types. It was demonstrated that emissions of biocides into water can be compared on the basis of leaching tests in which the emission kinetics of the active ingredients are recorded. However, the water volume per surface area and the timetable for water changes have to be defined in such tests. Functions of flux rates related to time can be well described for inorganic compounds, whereas modelling of the data is more complicated for organic substances. Emission chamber tests using 20-litre and 23-litre glass exsiccators, originally developed to study volatile organic compounds, were successfully adapted for the investigation of the emission of biocides from treated materials which are usually semi volatile organic compounds. However test parameters and the method of analysis have to be adapted to the substances to be determined. Generally, it was found that the emission curves for the semi volatile organic compounds investigated differ from those of volatile organic compounds.

  4. Leaching of biocides used in façade coatings under laboratory test conditions.

    Science.gov (United States)

    Schoknecht, Ute; Gruycheva, Jana; Mathies, Helena; Bergmann, Hannelore; Burkhardt, Michael

    2009-12-15

    The European Biocidal Products Directive 98/8/EC requires a risk assessment concerning possible effects of active ingredients on the environment. Biocides can be leached from treated materials exposed to outdoor use. These emissions have to be estimated and evaluated during the authorization procedure. Different immersion and irrigation tests were performed to investigate leaching of biocides from façade coatings. Several marketed formulations of textured coatings and paints spiked with a mixture of commonly used active ingredients (OIT, DCOIT, IPBC, carbendazim, isoproturon, diuron, terbutryn, and Irgarol 1051) were investigated. The emission process can be described by time-dependent functions that depend on the test conditions. The results of all test procedures confirm that leachability is related to water solubility and n-octanol-water partition coefficient of the active ingredients and that leaching of biocides from façade coatings is mainly a diffusion controlled process. Other factors like the composition of the product, availability and transport of water, concentration of active ingredients in the coatings, as well as UV-exposure of the coatings influence biocide emissions.

  5. Analysis of metal and biocides resistance genes in drug resistance and susceptible Salmonella enterica from food animals

    Science.gov (United States)

    Background Generally drug resistant bacteria carry antibiotic resistance genes and heavy metal and biocide resistance genes on large conjugative plasmids. The presence of these metal and biocide resistance genes in susceptible bacteria are not assessed comprehensively. Hence, WGS data of susceptib...

  6. Human exposure assessment for biocides in the EU development of step by step guidance and worked examples

    NARCIS (Netherlands)

    Gerritsen-Ebben, R.M.G.; Hemmen, J.J. van

    2007-01-01

    Directive 98/8/EC(1) concerns EU harmonisation of placing biocidal products on the market. In the present short paper the preliminary results of an ongoing project are presented in which step by step guidance on human exposure assessment with worked examples is developed. For all 23 biocidal product

  7. Effects of single and repeated exposure to biocidal active substances on the barrier function of the skin in vitro

    NARCIS (Netherlands)

    Buist, H.E.; Sandt, J.J.M. van de; Burgsteden, J.A. van; Heer, C. de

    2005-01-01

    The dermal route of exposure is important in worker exposure to biocidal products. Many biocidal active substances which are used on a daily basis may decrease the barrier function of the skin to a larger extent than current risk assessment practice addresses, due to possible skin effects of

  8. Use of bromine as biocide in cooling waters (Preprint No. CA-19)

    Energy Technology Data Exchange (ETDEWEB)

    Sriraman, A K [Bhabha Atomic Research Centre, Bombay (India). Water Chemistry Div.

    1989-04-01

    In all fresh water circuits, the slime forming bacteria develop an insulating layer on the condenser surfaces. If these bacteria are not controlled, they induce bacterial promoted corrosion of the materials in contact with cooling water. Chlorination is effective against slime forming bacteria, fungi and algae. The algistatic nature of the chlorine is partly compensated by the use of other non-oxidisable biocides. Amongst the various alternative biocides such as bromine, methyl bis-isocyanate, sodium pentachlorophenate etc, bromine is the most simple biocide, which is being increasingly used in cooling water systems. In this context, the chemistry of bromination and its bactericidal properties is examined along with those of chlorination. (author). 7 refs., 3 tabs., 2 figs.

  9. Thermal degradation of biocidal organic N-halamines and N-halamine polymers

    Energy Technology Data Exchange (ETDEWEB)

    Chylińska, Marta; Kaczmarek, Halina, E-mail: halina@chem.umk.pl

    2014-05-01

    Highlights: • Novel biocidal N-halamines have been substituted to poly(p-methyl styrene). • Thermal stability of all obtained compounds has been studied by thermogravimetry. • Stabilization of selected polymer has been achieved using octyl tin mercaptide. • The mechanism of thermal degradation of N-halamine polymers has been proposed. - Abstract: Novel biocidal organic N-halamines (based on imidazoline dione rings) were used as a substituents for poly(p-methyl styrene). The biocidal polymers and substituents have been investigated using thermogravimetric analysis. The thermal resistance of investigated compounds was compared to those of non-halogenated precursors. The introduction of chlorine atoms to polymers decreases their thermal resistance comparing to precursors but efficient stabilization is possible by using octyl tin mercaptide. The complex mechanism of thermal decomposition of polymers has been discussed.

  10. Development of a concept for the environmental risk assessment of biocidal products for authorization purposes. (BIOEXPO) Part 1: Framework and data requirements for environmental compartments

    NARCIS (Netherlands)

    Dokkum, H.P. van; Scholten, M.C.T.; Bakker, D.J.; Jak, R.G.; Bowmer, C.T.

    1998-01-01

    The BIOEXPO project is focussed on test data, required for the authorization of biocidal products. The draft EC Biocidal Products Directive distinguishes between a common core data set (Annex II) and an additional data set, with specific data requirements for biocidal product types (Annex III). The

  11. Exploring the sensitivity of the zone of inhibition test for leachable biocides from paper and board food contact materials, and improvements thereof.

    Science.gov (United States)

    Castle, L; Kelly, J; Jickells, S M; Johns, S M; Mountfort, K A

    2012-01-01

    The zone of inhibition method to test the release of biocides from paper and board food contact materials was evaluated. The method tests the paper by placing a small specimen directly onto culture plates of Bacillus subtilis and Aspergillus niger. The principle is that any extractable biocide will diffuse from the paper into the surrounding nutrient medium and so inhibit growth of the microorganism in the vicinity. The test was found to have insufficient sensitivity for assuring food safety, where detection limits for migration at or below the mg l(-1) (parts per million) level are needed. Also, the test does not mimic the actual or foreseeable conditions of use since most paper/board materials are not intended for direct contact with an aqueous medium for up to 3 days at 30°C (B. subtilis) or 25°C (A. niger), which are the incubation conditions used. The sensitivity of the test was increased approximately 100-fold by preparing a concentrated extract of the paper to be tested and applying this extract to the assay via a blank paper carrier. This was done using methanol as a good solvent for most biocides, as a proof of principle. Other solvents or food simulants could be used to mimic the conditions of use intended for the particular paper/board samples under examination, e.g. contact with dry, fatty, aqueous or acidic foods, hot or cold. Twenty-four plain (unconverted) paper and board samples and 100 food packaging samples were evaluated using the modified procedure. The results revealed that the method has been developed to the stage where background cytotoxic action of normal paper constituents gives a weak response. Unlike the original method, therefore, the modified method with its improved sensitivity and the facility to link with the intended food contact conditions may be considered a suitable bioassay screening test to complement chemical analysis of paper/board for composition and migration.

  12. Evaluation of the release characteristics of covalently attached or electrostatically bound biocidal polymers utilizing SERS and UV-Vis absorption

    Directory of Open Access Journals (Sweden)

    G. N. Mathioudakis

    2016-09-01

    Full Text Available In this work, biocidal polymers with antimicrobial quaternized ammonium groups introduced in the polymer biocidal chains either through covalent attachment or electrostatic interaction have been separately incorporated in a poly (methyl methacrylate polymer matrix. The objective of present study was to highlight the release characteristics of biocidal polymers, primarily in saline but also in water ethanol solutions, utilizing UV-Vis absorption and Surface Enhanced Raman Scattering (SERS. It is shown that through the combination of UV-Vis and SERS techniques, upon the release process, it is possible the discrimination of the polymeric backbone and the electrostatically bound biocidal species. Moreover, it is found that electrostatically bound and covalently attached biocidal species show different SERS patterns. The long term aim is the development of antimicrobial polymeric materials containing both ionically bound and covalently attached quaternary ammonium thus achieving a dual functionality in a single component polymeric design.

  13. Effects of antifouling biocides to the germination and growth of the marine macroalga, Hormosira banksii (Turner) Desicaine

    Energy Technology Data Exchange (ETDEWEB)

    Myers, Jackie H. [School of Ecology and Environment, Deakin University, P.O. Box 423, Warrnambool, Victoria 3280 (Australia) and Department of Primary Industries Research Victoria, Queenscliff, P.O. Box 114 Queenscliff, Victoria 3225 (Australia) and School of Biological Sciences, Monash University, Clayton Campus, Clayton, Victoria 3800 (Australia)]. E-mail jhmyers@deakin.edu.au; Gunthorpe, Leanne [Department of Primary Industries Research Victoria, Queenscliff, P.O. Box 114 Queenscliff, Victoria 3225 (Australia)]. E-mail Leanne.Gunthorpe@dpi.vic.gov.au; Allinson, Graeme [School of Ecology and Environment, Deakin University, P.O. Box 423, Warrnambool, Victoria 3280 (Australia)]. E-mail graemea@deakin.edu.au; Duda, Susan [Department of Primary Industries Research Victoria, Queenscliff, P.O. Box 114 Queenscliff, Victoria 3225 (Australia)]. E-mail Susan.Duda@dpi.vic.gov.au

    2006-09-15

    The International Maritime Organisation's (IMO) ban on the use of tributyltin in antifouling paints has inevitability increased the use of old fashioned antifoulants and/or the development of new paints containing 'booster biocides'. These newer paints are intended to be environmentally less harmful, however the broader environmental effects of these 'booster biocides' are poorly known. Germination and growth inhibition tests using the marine macroalga, Hormosira banksii (Turner) Desicaine were conducted to evaluate the toxicity of four new antifouling biocides in relation to tributyltin-oxide (TBTO). Each of the biocides significantly inhibited germination and growth of Hormosira banksii spores. Toxicity was in increasing order: diuron < zineb < seanine 211 < zinc pyrithione < TBTO. However, the lack of knowledge on partitioning in the environment makes it difficult to make a full assessment on whether the four biocides tested offer an advantage over organotin paints in terms of environmental impact.

  14. Effects of antifouling biocides to the germination and growth of the marine macroalga, Hormosira banksii (Turner) Desicaine

    International Nuclear Information System (INIS)

    Myers, Jackie H. . E-mail jhmyers@deakin.edu.au; Gunthorpe, Leanne . E-mail Leanne.Gunthorpe@dpi.vic.gov.au; Allinson, Graeme . E-mail graemea@deakin.edu.au; Duda, Susan . E-mail Susan.Duda@dpi.vic.gov.au

    2006-01-01

    The International Maritime Organisation's (IMO) ban on the use of tributyltin in antifouling paints has inevitability increased the use of old fashioned antifoulants and/or the development of new paints containing 'booster biocides'. These newer paints are intended to be environmentally less harmful, however the broader environmental effects of these 'booster biocides' are poorly known. Germination and growth inhibition tests using the marine macroalga, Hormosira banksii (Turner) Desicaine were conducted to evaluate the toxicity of four new antifouling biocides in relation to tributyltin-oxide (TBTO). Each of the biocides significantly inhibited germination and growth of Hormosira banksii spores. Toxicity was in increasing order: diuron < zineb < seanine 211 < zinc pyrithione < TBTO. However, the lack of knowledge on partitioning in the environment makes it difficult to make a full assessment on whether the four biocides tested offer an advantage over organotin paints in terms of environmental impact

  15. Control of Microbial Sulfide Production with Biocides and Nitrate in Oil Reservoir Simulating Bioreactors.

    Directory of Open Access Journals (Sweden)

    Yuan eXue

    2015-12-01

    Full Text Available Oil reservoir souring by the microbial reduction of sulfate to sulfide is unwanted, because it enhances corrosion of metal infrastructure used for oil production and processing. Reservoir souring can be prevented or remediated by the injection of nitrate or biocides, although injection of biocides into reservoirs is not commonly done. Whether combined application of these agents may give synergistic reservoir souring control is unknown. In order to address this we have used up-flow sand-packed bioreactors injected with 2 mM sulfate and volatile fatty acids (VFA, 3 mM each of acetate, propionate and butyrate at a flow rate of 3 or 6 pore volumes per day. Pulsed injection of the biocides glutaraldehyde (Glut, benzalkonium chloride (BAC and cocodiamine was used to control souring. Souring control was determined as the recovery time (RT needed to re-establish an aqueous sulfide concentration of 0.8-1 mM (of the 1.7-2 mM before the pulse. Pulses were either for a long time (120 h at low concentration (long-low or for a short time (1 h at high concentration (short-high. The short-high strategy gave better souring control with Glut, whereas the long-low strategy was better with cocodiamine. Continuous injection of 2 mM nitrate alone was not effective, because 3 mM VFA can fully reduce both 2 mM nitrate to nitrite and N2 and, subsequently, 2 mM sulfate to sulfide. No synergy was observed for short-high pulsed biocides and continuously injected nitrate. However, use of continuous nitrate and long-low pulsed biocide gave synergistic souring control with BAC and Glut, as indicated by increased RTs in the presence, as compared to the absence of nitrate. Increased production of nitrite, which increases the effectiveness of souring control by biocides, is the most likely cause for this synergy.

  16. Time-Dependent Antimicrobial Activity of Filtering Nonwovens with Gemini Surfactant-Based Biocides

    Directory of Open Access Journals (Sweden)

    Katarzyna Majchrzycka

    2017-09-01

    Full Text Available Previous studies on nonwovens used for respiratory protective devices (RPDs were related to equipment intended for short-term use. There is only limited research on the development of biocidal nonwoven fabrics for reusable RPDs that could be used safely in an industrial work environment where there is a risk of microbial growth. Moreover, a new group of biocides with high antimicrobial activity—gemini surfactants, has never been explored for textile’s application in previous studies. The aim of this study was to develop high-efficiency melt-blown nonwovens containing gemini surfactants with time-dependent biocidal activity, and to validate their antimicrobial properties under conditions simulating their use at a plant biomass-processing unit. A set of porous biocidal structures (SPBS was prepared and applied to the melt-blown polypropylene (PP nonwovens. The biocidal properties of the structures were triggered by humidity and had different activation rates. Scanning electron microscopy was used to undertake structural studies of the modified PP/SPBS nonwovens. In addition, simulation of plant biomass dust deposition on the nonwovens was performed. The biocidal activity of PP/SPBS nonwovens was evaluated following incubation with Escherichia coli and Aspergillus niger from the American Type Culture Collection, and with Pseudomonas fluorescens and Penicillium chrysogenum isolated from the biomass. PP/SPBS nonwovens exhibited antimicrobial activity to varying levels. Higher antimicrobial activity was noted for bacteria (R = 87.85–97.46% and lower for moulds (R = 80.11–94.53%.

  17. Emerging biocide resistance among multidrug-resistant bacteria: Myth or reality? A pilot study

    Directory of Open Access Journals (Sweden)

    Priyanka Gupta

    2018-01-01

    Full Text Available Context: Possible linkage between biocide and antibiotic resistance in bacteria is a major area of concern. Aim: To evaluate the susceptibility of multidrug-resistant (MDR bacteria to four commonly used biocides. Settings and Design: A pilot study was conducted in a tertiary care hospital from April to November 2017. Materials and Methods: Fifty-four MDR bacterial isolates, namely Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Staphylococcus aureus, were obtained from various clinical samples of inpatients. These isolates were subjected to tube dilution method for determining minimum inhibitory concentration (MIC of four commonly used biocides in our hospital, namely 5% w/v povidone iodine, absolute ethanol (99.9%, sodium hypochlorite (4% available chlorine, and quaternary ammonium compounds (QACs (3.39%. Minimum bactericidal concentration (MBC of these biocides was determined as per standard guidelines. Similar tests were also performed on corresponding American Type Culture Collection (ATCC bacterial strains. Statistical Analysis: The Fisher exact test. Results: Twenty-two MDR bacterial isolates had higher MIC values for QACs than their corresponding ATCC strains. Statistically significant difference in proportion of test isolates exhibiting higher MIC values for QACs and absolute ethanol was observed (P-value = 0.02. Twenty-four MDR bacterial isolates exhibited higher MBC values for sodium hypochlorite than their corresponding ATCC strains. The difference in proportion of test isolates exhibiting higher MBC values for sodium hypochlorite and absolute ethanol, respectively, was statistically significant (P-value <0.0001. The difference in proportion of test isolates exhibiting higher MBC values for absolute ethanol versus QACs and povidone iodine, respectively, was statistically significant (P-values = 0.0003 and 0.0076. Statistically significant differences in susceptibility to biocides among test isolates were also

  18. Use of a predictive protocol to measure the antimicrobial resistance risks associated with biocidal product usage.

    Science.gov (United States)

    Wesgate, Rebecca; Grasha, Pierre; Maillard, Jean-Yves

    2016-04-01

    In this study we assessed the propensity of biocide exposure in the development of antimicrobial resistance in bacteria. Our protocol is based on reporting changes in established antimicrobial susceptibility profiles in biocides and antibiotics after during use exposure to a product. The during use exposure reflects worse conditions of product use during application. It differs from the term low concentration, which usually reflects a concentration below the minimal inhibitory concentration, but not necessarily a concentration that occurs in practice. Our results showed that exposure to triclosan (0.0004%) was associated with a high risk of developing resistance and cross-resistance in Staphylococcus aureus and Escherichia coli. This was not observed with exposure to chlorhexidine (0.00005%) or a hydrogen peroxide-based biocidal product (in during use conditions). Interestingly, exposure to a low concentration of hydrogen peroxide (0.001%) carried a risk of emerging resistance to antibiotics if the presence of the oxidizing agent was maintained. We observed a number of unstable clinical resistances to antibiotics after exposure to the cationic biocide and oxidizing agent, notably to tobramycin and ticarcillin-clavulanic acid. Using a decision tree based on the change in antimicrobial susceptibility test results, we were able to provide information on the effect of biocide exposure on the development of bacterial resistance to antimicrobials. Such information should address the call from the U.S. Food and Drug Administration and European Union Biocidal Products Regulation for manufacturers to provide information on antimicrobial resistance and cross-resistance in bacteria after the use of their product. Copyright © 2016 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

  19. Biofilms and Oxidizing Biocides; Evaluation of Disinfection and Removal Effects by Using Established Microbial Systems.

    Science.gov (United States)

    Tachikawa, Mariko

    2017-01-01

    The formation of bacterial biofilms and their disinfection and removal have been important subjects in the maintenance of water quality in areas such as public spas, swimming pools, food processing lines, industrial water systems, and in the hygienic control of medical devices, hospital procedures, etc. Presented here is an outline of biofilm formation, as well as studies on the disinfection and removal of biofilms by oxidizing biocides using established biofilms. These studies using established biofilms may increase the understanding of the variable response of biofilms to planktonic bacteria, and the unique aspects of oxidizing biocides in the disinfection and removal of biofilms.

  20. Possible underestimations of risks for the environment due to unregulated emissions of biocides from households to wastewater.

    Science.gov (United States)

    Wieck, Stefanie; Olsson, Oliver; Kümmerer, Klaus

    2016-09-01

    The aim of this study was to investigate the role of household products as possible sources of biocidal active substances in municipal wastewater and their regulation under the Biocidal Products Regulation (EU) 528/2012. In 131 households, we investigated the prevalence of products used to control pests, washing and cleaning agents and select personal care products with high release to wastewater. Inventories of these products were established with the help of barcode scanning. All uses of biocidal active substances were evaluated regarding their assessment under the Biocidal Products Regulation. 2963 products were scanned in total, with 48% being washing and cleaning agents, 43% personal care products and 9% products used to control pests. Biocidal active substances were found in each household. These were observed primarily in washing and cleaning agents and personal care products (90%), while only a small percentage of the observations of biocidal active substances was in biocidal products. 64% of the observations of biocidal active substances were in applications that do not fall under the Biocidal Products Regulation and are thus not subject to its environmental risk assessment. This study shows clearly that risks for the environment are underestimated because unregulated emissions to wastewater occur. It demonstrates that there are gaps in the current chemical legislation that lead to a release of substances into wastewater that were not subject to environmental risk assessment under the Biocidal Products Regulation. This is one example of the limitations of scientific risk assessment of chemicals - its complexity is immense. From our point of view, the results underline the importance of a sustainable use of the substances as this is the only way to decrease yet unidentified risks. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Polypropylene film with silver nanoparticles and nanoclay aiming to action biocidal

    International Nuclear Information System (INIS)

    Oliani, W.L.; Lima, L.F.C.P.; Lugao, A.B.; Parra, D.F.; Fermino, D.M.; Diaz, F.R.V.

    2014-01-01

    This paper presents an initial study of films made of polypropylene nanoclay and silver nanoparticles. The nanocomposite of polypropylene (iPP), commercial organoclay - montmorillonite (MMT), Cloisite 20A at concentrations of 1.0% and silver nanoparticles (AgNPs) at a concentration of 0.1% were prepared in a twin-screw-extruder, using polypropylene with maleic anhydride (PP-g-MA) as coupling agent. The properties of nanocomposites of PP/MMT/AgNPs are closely related to the dispersion of silver particles and the distribution of sheets of MMT in the polymer matrix, which define its efficiency in the case of the particles and their interaction clay/polymer matrix. However, this combination of MMT and AgNPs that are polar, with the polymer matrix nonpolar in the molten state, presents a challenge. The characterization of the film was performed by analysis of X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and reduction of colony forming unit (CFU %). The results indicate the formation of predominantly exfoliated microstructures and agglomeration of silver nanoparticles in the film. The effect of silver nanoparticles was evaluated against bacteria E.coli and S.aureus. (author)

  2. A passive apparatus for controlled-flux delivery of biocides: hydrogen peroxide as an example

    DEFF Research Database (Denmark)

    Olsen, Stefan Møller; Pedersen, L.T.; Dam-Johansen, Kim

    2010-01-01

    A new test method has been developed to estimate the required release rate of hydrogen peroxide (H2O2) to prevent marine biofouling. The technique exploits a well-defined concentration gradient of biocide across a cellulose acetate membrane. A controlled flux of H2O2, an environmentally friendly ...

  3. Controlled release for crop and wood protection: Recent progress toward sustainable and safe nanostructured biocidal systems.

    Science.gov (United States)

    Mattos, Bruno D; Tardy, Blaise L; Magalhães, Washington L E; Rojas, Orlando J

    2017-09-28

    We review biocide delivery systems (BDS), which are designed to deter or control harmful organisms that damage agricultural crops, forests and forest products. This is a timely topic, given the growing socio-economical concerns that have motivated major developments in sustainable BDS. Associated designs aim at improving or replacing traditional systems, which often consist of biocides with extreme behavior as far as their solubility in water. This includes those that compromise or pollute soil and water (highly soluble or volatile biocides) or those that present low bioavailability (poorly soluble biocides). Major breakthroughs are sought to mitigate or eliminate consequential environmental and health impacts in agriculture and silviculture. Here, we consider the most important BDS vehicles or carriers, their synthesis, the environmental impact of their constituents and interactions with the active components together with the factors that affect their rates of release such as environmental factors and interaction of BDS with the crops or forest products. We put in perspective the state-of-the-art nanostructured carriers for controlled release, which need to address many of the challenges that exist in the application of BDS. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. N-halamine biocidal coatings via a layer-by-layer assembly technique.

    Science.gov (United States)

    Cerkez, Idris; Kocer, Hasan B; Worley, S D; Broughton, R M; Huang, T S

    2011-04-05

    Two N-halamine copolymer precursors, poly(2,2,6,6-tetramethyl-4-piperidyl methacrylate-co-acrylic acid potassium salt) and poly(2,2,6,6-tetramethyl-4-piperidyl methacrylate-co-trimethyl-2-methacryloxyethylammonium chloride) have been synthesized and successfully coated onto cotton fabric via a layer-by-layer (LbL) assembly technique. A multilayer thin film was deposited onto the fiber surfaces by alternative exposure to polyelectrolyte solutions. The coating was rendered biocidal by a dilute household bleach treatment. The biocidal efficacies of tested swatches composed of treated fibers were evaluated against Staphylococcus aureus and Escherichia coli. It was determined that chlorinated samples inactivated both S. aureus and E. coli O157:H7 within 15 min of contact time, whereas the unchlorinated control samples did not exhibit significant biocidal activities. Stabilities of the coatings toward washing and ultraviolet light exposure have also been studied. It was found that the stability toward washing was superior, whereas the UVA light stability was moderate compared to previously studied N-halamine moieties. The layer-by-layer assembly technique can be used to attach N-halamine precursor polymers onto cellulose surfaces without using covalently bonding tethering groups which limit the structure designs. In addition, ionic precursors are very soluble in water, thus promising for biocidal coatings without the use of organic solvents.

  5. Effect of enterocin AS-48 in combination with biocides on planktonic and sessile Listeria monocytogenes.

    Science.gov (United States)

    Gómez, Natacha Caballero; Abriouel, Hikmate; Grande, M A José; Pulido, Rubén Pérez; Gálvez, Antonio

    2012-05-01

    Enterocin AS-48 was tested on a cocktail of Listeria monocytogenes strains in planktonic and sessile states, singly or in combination with biocides benzalkonium chloride, cetrimide, hexadecylpyridinium chloride, didecyldimethylammonium bromide, triclosan, poly-(hexamethylen guanidinium) hydrochloride, chlorhexidine, hexachlorophene, and the commercial sanitizers P3 oxonia and P3 topax 66. Combinations of sub-inhibitory bacteriocin concentrations and biocide concentrations 4 to 10-fold lower than their minimum inhibitory concentrations (MIC) completely inhibited growth of the planktonic listeriae. Inactivation of Listeria in biofilms formed on polystyrene microtiter plates required concentrations of enterocin AS-48 greater than 50 μg/ml, and biocide concentrations ten to 100-fold higher. In combination with enterocin AS-48 (25 or 50 μg/ml), microbial inactivation increased remarkably for all biocides except P3 oxonia and P3 topax 66 solutions. Polystyrene microtiter plates conditioned with enterocin solutions (0.5-25 μg/ml) decreased the adherence and biofilm formation of the L. monocytogenes cell cocktail, avoiding biofilm formation for at least 24 h at a bacteriocin concentration of 25 μg/ml. Copyright © 2011 Elsevier Ltd. All rights reserved.

  6. Monitoring of the booster biocide dichlofluanid in water and marine sediment of Greek marinas

    NARCIS (Netherlands)

    Hamwijk, C.; Schouten, A.; Foekema, E.M.; Ravensberg, J.C.; Collombon, M.T.; Schmidt, K.; Kugler, M.

    2005-01-01

    Dichlofluanid (N-dichlorofluoromethylthio-N′-dimethyl-N- phenylsulphamide) is used as booster biocide in antifouling paints. The occurrence of dichlofluanid and its metabolite DMSA (N′-dimethyl-N-phenyl- sulphamide) was monitored in seawater and marine sediment from three Greek marinas. Seawater and

  7. Decreased bio-inhibition of building materials due to transport of biocides

    NARCIS (Netherlands)

    Erich, S.J.F.; Mendoza, S.M.; Floor, W.; Hermanns, S.P.M.; Homan, W.J.; Adan, O.C.G.

    2011-01-01

    Bio-inhibition of buildings and structures is an important issue. In many cases building materials have biocides added to prevent growth of micro-organisms. Growth of microorganisms on building materials has several negative effects; (1) Aesthetic damage, e.g. fungi, algae grow on the material,

  8. Development of detection techniques for monitoring and optimizing biocide dosing in seawater flooding systems

    NARCIS (Netherlands)

    Al-Moniee, M.A.; Al-Abeedi, F.N.; Koopal, C.G.J.; Akmal, N.; Sanders, P.F.; Veen, S. van

    2013-01-01

    Anaerobic microorganisms which are frequently associated with corrosion fail Control of bacterial activity are posing major challenge in Saudi Arabia's massive seawater flooding systems. Biocides are used to control bacteria throughout the oil industry. A study to explore the feasibility to develop

  9. Optimization of the cumulative risk assessment of pesticides and biocides using computational techniques: Pilot project

    DEFF Research Database (Denmark)

    Jonsdottir, Svava Osk; Reffstrup, Trine Klein; Petersen, Annette

    This pilot project is intended as the first step in developing a computational strategy to assist in refining methods for higher tier cumulative and aggregate risk assessment of exposure to mixture of pesticides and biocides. For this purpose, physiologically based toxicokinetic (PBTK) models were...

  10. Alkyl ammonium cation stabilized biocidal polyiodides with adaptable high density and low pressure.

    Science.gov (United States)

    He, Chunlin; Parrish, Damon A; Shreeve, Jean'ne M

    2014-05-26

    The effective application of biocidal species requires building the active moiety into a molecular back bone that can be delivered and decomposed on demand under conditions of low pressure and prolonged high-temperature detonation. The goal is to destroy storage facilities and their contents while utilizing the biocidal products arising from the released energy to destroy any remaining harmful airborne agents. Decomposition of carefully selected iodine-rich compounds can produce large amounts of the very active biocides, hydroiodic acid (HI) and iodine (I2). Polyiodide anions, namely, I3(-), I5(-), which are excellent sources of such biocides, can be stabilized through interactions with large, symmetric cations, such as alkyl ammonium salts. We have designed and synthesized suitable compounds of adaptable high density up to 3.33 g cm(-3) that are low-pressure polyiodides with various alkyl ammonium cations, deliverable iodine contents of which range between 58.0-90.9%. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. BIOCIDAL PRODUCTS – IMPLICATIONS OF THEIR USAGE IN THE ANTIBIOTIC RESISTANCE INITIATION

    Directory of Open Access Journals (Sweden)

    Mariana Dumitrache

    2016-12-01

    Full Text Available Biocidal products are necessary in our lives in order to protect us against pathogenic microorganisms. But their use must be subject to a strict regulation because their harmful potential on human and animal health and environment is huge. Biocidal products must be authorized by a competent authority before placing them on the market and all active substances from their composition must be tested and certified to ensure they are in compliance with regulatory requirements in the field. Also biocides, with antimicrobials, may be involved in causing the phenomenon of antibiotic resistance. Their misuse can lead to the emergence of resistant organisms, through mechanisms similar to those that appear in incorrect treatment with antibiotics. We should, therefore, be aware of this aspect particularly important to prevent unwanted effects of cross resistance to antibiotics and biocides. The more so as, lately, there are pulled many alarm signals about the fact that, in a very short time, mankind is in danger of remaining without the main arsenal for fighting harmful microorganisms.

  12. Correlation between antibiotic and biocide resistance in mesophilic and psychrotrophic Pseudomonas spp. isolated from slaughterhouse surfaces throughout meat chain production.

    Science.gov (United States)

    Lavilla Lerma, Leyre; Benomar, Nabil; Casado Muñoz, María del Carmen; Gálvez, Antonio; Abriouel, Hikmate

    2015-10-01

    The aim of this study was to evaluate biocide susceptibility in mesophilic and psychrotrophic pseudomonads isolated from surfaces of a goat and lamb slaughterhouse, which was representative of the region. To determine biocide resistance in pseudomonads, we determined for the first time the epidemiological cut-off values (ECOFFs) of benzalkonium, cetrimide, chlorhexidine, hexachlorophene, P3 oxonia, polyhexamethylene guanidine hydrochloride (PHMG), topax 66 and triclosan being generally very similar in different Pseudomonas spp. with some exceptions. Thus, resistance of pseudomonads was mainly shown to triclosan, and in lesser extent to cetrimide and benzalkonium chloride depending on the species, however they were highly susceptible to industrial formulations of biocides. By means of statistical analysis, positive correlations between antibiotics, biocides and both antimicrobials in pseudomonads were detected suggesting a co- or cross resistance between different antimicrobials in goat and lamb slaughterhouse environment. Cross-resistance between biocides and antibiotics in pseudomonads were especially detected between PHMG or triclosan and different antibiotics depending on the biocide and the population type. Thus, the use of those biocides as disinfectant in slaughterhouse zones must be carefully evaluated because of the selection pressure effect of antimicrobials on the emergence of resistant bacteria which could be spread to the consumer. It is noteworthy that specific industrial formulations such as topax 66 and oxonia P3 showed few correlations with antibiotics (none or 1-2 antibiotics) which should be taken into consideration for disinfection practices in goat and lamb slaughterhouse. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Study of a Mathematical Model of Biocide Effect on a Biofilm Isolated from a Cooling System Using the Microtiter Plate

    Directory of Open Access Journals (Sweden)

    Shahryar Shakeri

    2005-06-01

    Full Text Available Bacterial colonization on metal surfaces and their metabolic activities lead to biocorrosion. In fact, any agent removing the biofilm or decreasing its thickness is capable of preventing biocorrosion. Biocides make up one such agent. These agents can control bacterial biofilms, remove these structures, or kill cells within them. The object of this research is to study the thermodynamic model of biocide penetration into the biofilm using the microtiter plate test. First, the biofilm bacteria were isolated to form a mix- bacterial biofilm. The biocide effect on the mix-biofilm was then determined using the microtiter plate test. Results from this test were compared with those from a thermodynamic model and it was revealed that the effects of oxidizing biocides such as sodium hypochlorite and hydrogen peroxide are in good agreement with the results from the model. The results indicated that increased biocide concentration leads to the removal of the biofilm or to the kill-off of the cells within it. However, in the case of non-oxidizing biocides such as sulfathiazol, glutaraldehyde, and alkyl dimethyl ammonium chloride, the efficiency results did not agree well with the results from the thermodynamic model such that increased biocide concentration did not remove the biofilm nor did it kill off the cells within it

  14. Leaching of biocides from building facades: Upscaling of a local two-region leaching model to the city scale

    Science.gov (United States)

    Coutu, S.; Rota, C.; Rossi, L.; Barry, D. A.

    2011-12-01

    Facades are protected by paints that contain biocides as protection against degradation. These biocides are leached by rainfall (albeit at low concentrations). At the city scale, however, the surface area of building facades is significant, and leached biocides are a potential environmental risk to receiving waters. A city-scale biocide-leaching model was developed based on two main steps. In the first step, laboratory experiments on a single facade were used to calibrate and validate a 1D, two-region phenomenological model of biocide leaching. The same data set was analyzed independently by another research group who found empirically that biocide leachate breakthrough curves were well represented by a sum of two exponentials. Interestingly, the two-region model was found analytically to reproduce this functional form as a special case. The second step in the method is site-specific, and involves upscaling the validated single facade model to a particular city. In this step, (i) GIS-based estimates of facade heights and areas are deduced using the city's cadastral data, (ii) facade flow is estimated using local meteorological data (rainfall, wind direction) and (iii) paint application rates are modeled as a stochastic process based on manufacturers' recommendations. The methodology was applied to Lausanne, Switzerland, a city of about 200,000 inhabitants. Approximately 30% of the annually applied mass of biocides was estimated to be released to the environment.

  15. The effects of biocides (antiseptics and disinfectants on the endospores of Rhinosporidium seeberi

    Directory of Open Access Journals (Sweden)

    Arseculeratne S

    2006-01-01

    Full Text Available No data exists on the activity of biocides (antiseptics and disinfectants on Rhinosporidium seeberi that causes rhinosporidiosis in humans and animals. On account of the inability to culture R. seeberi, in vitro , dyes were used to assess the morphological integrity and viability of biocide-treated endospores that are considered to be the infective stage of this pathogen. Evan′s Blue (EvB identifies the morphological integrity of the endospores while MTT (3-[4, 5-dimethylthiazol-2yl]-2, 5-diphenyl tetrazolium bromide identifies metabolic activity through its reduction by cellular dehydrogenases to microscopically visible deposits of insoluble formazan. MTT-negativity has earlier been shown to correlate with absence of growth of yeast and mycelial fungi in culture and could thus indicate the loss of viability of MTT-negative rhinosporidial endospores. Hydrogen peroxide, glutaraldehyde, chloroxylenol, chlorhexidine, cetrimide, thimerosal, 70% ethanol, iodine in 70% ethanol, 10% formalin, povidone-iodine, sodium azide and silver nitrate were tested on freshly-harvested endospores and all biocides caused metabolic inactivation with or without altered structural integrity as shown by absence of MTT-staining after 3, 24 or 36 hour after exposure, while EvB stained only the endospores treated with sodium azide, ethanol, thimerosal, chloroxylenol, glutaraldehyde and hydrogen peroxide. With clinically useful biocides - chlorhexidine, cetrimide-chlorhexidine, 70% ethanol, povidone-iodine and silver nitrate, a total period of exposure of endospores to the biocide, for seven minutes, produced metabolic inactivation of the endospores. Anti-rhinosporidial antiseptics that could be used in surgery on rhinosporidial patients include povidone-iodine in nasal packs for nasal and naso-pharyngeal surgery, chlorhexidine and cetrimide-chlorhexidine on the skin, while povidone-iodine and silver nitrate could have application in ocular rhinosporidiosis.

  16. Choice of optimal biocide combination to control flies (Diptera: Muscidae

    Directory of Open Access Journals (Sweden)

    Mihaela Kavran

    2015-05-01

    Full Text Available Introduction. Flies – by feeding on decaying matter, human waste and food – have been implicated in the spread of numerous animal and human diseases. Excessive fly populations are generally associated with livestock units and domestic waste due to decaying organic matter. A large number of flies cause extreme disturbance in the behavior of the host, resulting in skin irritation, lesions, wounds, and secondary infections are likely to appear. Objective. The aim of this study was to evaluate the effects of combined applications of larvicide (cyromazine and adulticides (acetamiprid in formulation with pheromone and thiamethoxam on the suppression of fly populations. Materials and methods. The study was conducted on a pig farm. The piglet farms are one of the most favorable places for fly breeding. Three units were used for biocide applications and a fourth unit as the control where biocides were not applied. The monitoring of pre- and post-treatment of adult fly populations was carried out by glued cardboards. The cards were hung on metal rods above piglet’s cage. This monitoring method served as a parameter for the estimation of biological effectiveness. Results. The highest degree of fly control (88.4% mortality 8 days after treatment was achieved when a combination of cyromazine and thiamethoxam was used. A biocide based on sex pheromone (Z-9-tricosene + acetamiprid was the most effective on flies 3 days after biocide application, with a mortality rate of 69.1 %. Thiamethoxam achieved the highest reduction of flies 6 days after treatment, with 78.19% obtained mortality. Conclusion. Biological efficacy of the applied biocides in combination ciromazine + thiamethoxam and thiamethoxam alone was justified.

  17. Development of a concept for the environmental risk assessment of biocidal products for authorization purposes (BIOEXPO). Executive summary

    OpenAIRE

    Dokkum, H.P. van; Scholten, M.C.Th.; Bakker, D.J.

    1998-01-01

    The Biocidal Products Directive (Draft 97/C69/03; latest version December 12' 1997, 95/0465 (COD); PE CONS 3633/97) will complete the European chemicals regulation, which consists of the directives on existing substances (Council regu-lation 793/93), new substances (Directive 92/32/EC) and agricultural pesticides (Directive 91/414/EC). Biocides include a wide range of product types, such as pest control products, disinfectants, preservatives, and antifouling products. In Annex V of the Biocid...

  18. Commercial biocides induce transfer of prophage Φ13 from human strains of Staphylococcus aureus to livestock CC398

    DEFF Research Database (Denmark)

    Tang, Yuanyue; Nielsen, Lene Nørby; Hvitved, Annemette

    2017-01-01

    if exposure to biocidal products induces phage transfer, and find that during co-culture, Φ13 from strain 8325, belonging to ΦSa3 group, is induced and transferred from a human strain to LA-MRSA CC398 when exposed to sub-lethal concentrations of commercial biocides containing hydrogen peroxide. Integration...... variation in CC398 strains that disrupts the phage attachment site, but not the expression of β-hemolysin. Our results show that hydrogen peroxide present in biocidal products stimulate transfer of ΦSa3 from human to LA-MRSA CC398 strains and that in these strains prophage stability depends...

  19. Where was ENSO strongest?

    Science.gov (United States)

    Cane, M. A.; Chen, D.; Kaplan, A.

    2008-12-01

    Mark A. Cane, Dake Chen, Alexey Kaplan The description of this session begins: "Historical SST records suggest that for the past three decades, ENSO has been anomalously strong" and goes on to ask why. In this talk we dispute this interpretation of the historical record from within the historical record. In particular, we suggest that the most "anomalously strong" period in the historical ENSO record is the late nineteenth century. This claim requires a discussion of how we measure "ENSO strength". We also speculate on possible reasons for the strength of ENSO in this earlier period. Finally, we consult the models, and in reiteration of the collective conclusion of all speakers at this session, find that the riddles the models provide are inelegant and disobliging, lacking the cryptic wisdom of the classical oracles.

  20. A systems integration approach to the optimum operation and scheduling of biocide usage and discharge for seawater cooling systems

    KAUST Repository

    Mahfouz, Abdullah Bin

    2012-01-01

    The objective of this work is to develop a systematic approach to the optimal design and integration of seawater cooling systems in industrial facilities along with the usage and discharge of biocides. Specifically, the paper will address the following tasks: 1 identification of the reaction pathways for the biocide from the mixing basin to the discharge points 2 kinetic modelling of the biocide and by-products throughout the process 3 a process integration framework to provide a holistic approach to optimising the design and operation of the seawater cooling systems, along with the dosage and discharge systems. A hierarchical procedure is developed to first identify design modifications for heat integration and energy efficiency. Then, a multi-period, multi-segment optimisation formulation is developed and solved to identify the optimal operation and scheduling of biocide usage and discharge. A case study is solved to illustrate the applicability of the devised approach.

  1. Comparison of Authorization/Registration/Notification Processes among Biocidal Products, Cosmetics, Plant Protection Products and Human Medicinal Products

    OpenAIRE

    Söyleriz, Yüksel

    2015-01-01

    In this study, comparison of the authorization/registration/notification processes of biocidal products, cosmetics, plant protection products and medicinal products are made and in this respect, the situation in EU is assessed.

  2. A systems integration approach to the optimum operation and scheduling of biocide usage and discharge for seawater cooling systems

    KAUST Repository

    Mahfouz, Abdullah Bin; Atilhan, Selma; Batchelor, Bill; Linke, Patrick; Wahab, Ahmed Abdel; Halwagi, Mahmoud M. El

    2012-01-01

    The objective of this work is to develop a systematic approach to the optimal design and integration of seawater cooling systems in industrial facilities along with the usage and discharge of biocides. Specifically, the paper will address

  3. Biocides in hydraulic fracturing: A comparison to agricultural and assessment of hazard and vulnerability with respect to groundwater pollution

    Science.gov (United States)

    Worrall, Fred; Wilson, Miles; Davies, Richard

    2017-04-01

    Biocides are one possible chemical additive to frack fluids and their role is to control bacterial growth. Since biocides are designed to be toxic to particular organisms, their accidental or deliberate release into the environment has become a growing topic of concern, especially with regards to fracking. The objective of this study was to consider whether biocides proposed for use in fracking, could be a threat to English groundwater based on past groundwater monitoring data. The study considered all groundwater samples analysed for biocides in English groundwater between 2005 and 2014. The monitoring records were compared to: records of application (both amount and area); and chemical and molecular data for the biocides. The study did not use traditional adsorption and degradation data as these parameters are prone to variability and are not pure molecular parameters. The study showed that of the 110 biocides tested for in English groundwaters in the decade 2005 - 2014. The total number of detections was 2234 out of 1475000 observations of 95 compounds, and 38 were compounds that were not applied during the period of record. The detection of these 38 compounds did not decline over the 10 year period implying very long residence times and that once compounds do pollute an aquifer, then they will be a persistent problem. The study was able to develop binomial regression models of the probability of detecting pesticide in groundwater based upon molecular and application variables; and solely upon molecular properties. The solubility of the range of biocides used in frack fluids would imply a potentially higher hazard than for most agricultural biocides, but molecular modelling implied that one compound could be safer than others.

  4. Not only biocidal products: Washing and cleaning agents and personal care products can act as further sources of biocidal active substances in wastewater.

    Science.gov (United States)

    Wieck, Stefanie; Olsson, Oliver; Kümmerer, Klaus

    2018-06-01

    The emission sources of biocidal active substances in households have been under discussion since these substances have been detected frequently in municipal wastewater and receiving surface water bodies. Therefore, the goal of this study was to investigate the products responsible for the emission of these substances to wastewater. We analysed the wastewater of two streets for a set of biocidal active substances. Time-proportional sampling was conducted for one week of each season during one year in each street. The 14 substances analysed with liquid chromatography coupled with tandem mass spectrometry were 1,2-benzisothiazol-3(2H)-one (BIT), C 12 -benzalkonium chloride, carbendazim, 5-chloro-2-methyl-2H-isothiazol-3-one (CMIT), dichlorooctylisothiazolinone (DCOIT), N,N-diethyl-meta-toluamide (DEET), diuron, icaridine, 2-octyl-2H-isothiazol-3-one (OIT), piperonyl butoxide (PBO), triclosan, tebuconazole, terbutryn and tetramethrin. Using data available from household product inventories of the two streets, we searched the lists of ingredients for the products possibly being responsible for the emissions. Except for four substances, all substances have been detected in at least 10% of the samples. Highest concentrations were measured for C 12 -benzalkonium chloride with an average concentration in the daily samples of 7.7 μg/L in one of the streets. Next to C 12 -benzalkonium chloride, BIT, DEET and icaridine were detected in all samples in average concentrations above 1 μg/L in at least one street. The results show that washing and cleaning agents were important sources for preservatives such as BIT and OIT, while triclosan was apparently mainly emitted through personal care products. The mosquito repelling substances DEET and icaridine were found throughout the year, with highest emissions in summer and autumn. In conclusion, the results demonstrate that the sources of biocidal active substances in municipal wastewater are complex and that measures for the

  5. Synthesis of biocidal polymers containing metal NPs using an electron beam

    International Nuclear Information System (INIS)

    Choi, Kwonyong; Kim, Seong-Eun; Kim, Hee-Yeon; Yoon, Jeyong; Lee, Jong-Chan

    2012-01-01

    Metal containing antibacterial polymers were prepared by the polymerization of methylmethacrylate and methacrylic acid with copper or zinc. When the thin film of the polymers coated on a glass was irradiated with an electron beam, nanoparticles were obtained. It was found that these polymers exhibited a potent antibacterial activity against the Gram-negative bacteria, Escherichia coli. The metal containing polymers showed a 99.999% (5.0 logs) reduction in E. coli at a contact time of 12 h. In addition, polymers had a good antifouling effect against marine organisms. - Graphical abstract: Biocidal activity of Cu nanoparticle/polymer composite film against Gram-negative bacteria. Highlights: ► Metal containing antibacterial polymers were prepared with copper. ► Using the electron beam, nanoparticles were obtained. ► It was found that these polymers exhibited potent biocidal activity against E. coli. ► The metal containing polymers showed a 99.999% reduction of E. coli.

  6. TetrakisHydroxymethylPhosphonium Sulfate (THPS), a new industrial biocide with low environmental toxicity

    International Nuclear Information System (INIS)

    Downward, B.L.; Talbot, R.E.; Haack, T.K.

    1997-01-01

    THPS is a new biocide active designed for use in a variety of environmentally sensitive applications such as industrial cooling systems and oilfield situations. EPA registration has recently been achieved thus permitting, for the first time, the use of THPS based biocides in the US. This paper reviews the chemistry of THPS and reports a variety of case histories where THPS has successfully been used for the control of bacteria, algae and fungi in industrial cooling systems in Western Europe. An extensive data package, including field applications and laboratory studies, is available for THPS providing many exciting opportunities for this product in the US. Case studies are presented for a cooling system in a fuel reprocessing plant, a process water system for a textile plant, and cooling systems for a chemical plant and a confectionary site

  7. Assessment of TBT and organic booster biocide contamination in seawater from coastal areas of South Korea.

    Science.gov (United States)

    Kim, Nam Sook; Shim, Won Joon; Yim, Un Hyuk; Hong, Sang Hee; Ha, Sung Yong; Han, Gi Myung; Shin, Kyung-Hoon

    2014-01-15

    Seawater samples from major enclosed bays, fishing ports, and harbors of Korea were analyzed to determine levels of tributyltin (TBT) and booster biocides, which are antifouling agents used as alternatives to TBT. TBT levels were in the range of not detected (nd) to 23.9 ng Sn/L. Diuron and Irgarol 1051, at concentration ranges of 35-1360 ng/L and nd to 14 ng/L, respectively, were the most common alternative biocides present in seawater, with the highest concentrations detected in fishing ports. Hot spots were identified where TBT levels exceeded environmental quality targets even 6 years after a total ban on its use in Korea. Diuron exceeded the UK environmental quality standard (EQS) value in 73% of the fishing port samples, 64% of the major bays, and 42% of the harbors. Irgarol 1051 levels were marginally below the Dutch and UK EQS values at all sites. Copyright © 2013 Elsevier Ltd. All rights reserved.

  8. Encapsulation of Antifouling Organic Biocides in Poly(lactic acid) Nanoparticles.

    Science.gov (United States)

    Kamtsikakis, Aristotelis; Kavetsou, Eleni; Chronaki, Konstantina; Kiosidou, Evangelia; Pavlatou, Evangelia; Karana, Alexandra; Papaspyrides, Constantine; Detsi, Anastasia; Karantonis, Antonis; Vouyiouka, Stamatina

    2017-09-26

    The scope of the current research was to assess the feasibility of encapsulating three commercial antifouling compounds, Irgarol 1051, Econea and Zinc pyrithione, in biodegradable poly(lactic acid) (PLA) nanoparticles. The emulsification-solvent evaporation technique was herein utilized to manufacture nanoparticles with a biocide:polymer ratio of 40%. The loaded nanoparticles were analyzed for their size and size distribution, zeta potential, encapsulation efficiency and thermal properties, while the relevant physicochemical characteristics were correlated to biocide-polymer system. In addition, the encapsulation process was scaled up and the prepared nanoparticles were dispersed in a water-based antifouling paint in order to examine the viability of incorporating nanoparticles in such coatings. Metallic specimens were coated with the nanoparticles-containing paint and examined regarding surface morphology.

  9. Emission of biocides from hospitals: comparing current survey results with European Union default values.

    Science.gov (United States)

    Tluczkiewicz, Inga; Bitsch, Annette; Hahn, Stefan; Hahn, Torsten

    2010-04-01

    Under the European Union (EU) Biocidal Products Directive 98/8/EC, comprehensive evaluations on substances of the Third Priority List were conducted until 31 July 2007. This list includes, among other categories, disinfectants for human hygiene (e.g., skin and surface disinfection). For environmental exposure assessment of biocides, the EU emission scenarios apply. Currently available default values for disinfectants are based on consumption data from not more than 8 hospitals and were originally assembled for other purposes. To revalidate these default values, a survey on annual consumption data was performed in 27 German hospitals. These data were analyzed to provide consumption data per bed and day and per nurse and day for particular categories of active ingredients and were compared with default values from the EU emission scenario documents. Although several deviations were detected, an overall acceptable correspondence between Emission Scenario Documents default values and the current survey data was found. (c) 2009 SETAC

  10. A Photodegradation Study of Three Common Paint and Plaster Biocides under monochromatic UV Light

    DEFF Research Database (Denmark)

    Minelgaite, Greta; Vollertsen, Jes; Nielsen, Asbjørn Haaning

    2014-01-01

    Photodegradation of the three common paint-and-plaster biocides (carbendazim, diuron and terbutryn) was investigated at controlled laboratory conditions. Samples prepared in two types of water (demineralized water and pond water) were subjected to 254 nm monochromatic UV light. Light intensity (W m......-2) in the experimental chamber was measured by a fiber optic spectrometer. The observed decline in biocide concentration was related with the light energy, accumulated during the time of degradation (kJ m-2), and 1st order photodegradation rate constants (m2 kJ-1) were determined. The obtained...... at selected laboratory conditions, as well as emphasize the importance of water type when investigating pollutant’s photo fate, as certain constituents might act as reaction enhancers or inhibitors....

  11. Impedimetric test for rapid determination of performic acid (PFA) biocidal activity toward Echerichia coli

    OpenAIRE

    Małgorzata Lasik; Renata Dobrucka; Piotr Konieczny

    2013-01-01

      Background. Performic acid has recently become available on a commercial scale for potential use in waste-water disinfection and can become an innovative biocide for various purposes in food processing. The aim of our study was: 1) to investigate the antimicrobial resistance of performic acid as high active and non toxic chemical disinfectant against Escherichi coli (hygiene indicator test  microorganism used in industrial micro- biology) and 2) to evaluate the electrical impedanc...

  12. Assesment of the legislation about biocidal products produced by nanotechnology in Turkey

    OpenAIRE

    Terzi, Özlem; Köksal, Elif Nur

    2018-01-01

    The aimofthis study is to determine whether the legislations in Turkey includebiocidal products produced by nanotechnology. The data were obtained fromscientific articles and Official Gazette website. Results: In our daily life,due to their antibacterial and antifungal characteristics, nanoparticles (NP)derived from some metal and metal oxides are used in food and textile productsas protector. In addition, antimicrobial features of biocidal products becomemore effective by means of nanotechno...

  13. Analysis of the competitive activities of Ukrainian champions with the strongest fighters of world (based on world championship in Greco-Roman wrestling in 2011

    Directory of Open Access Journals (Sweden)

    Radchenko Y.А.

    2012-06-01

    Full Text Available The comparative analysis of results of competition activity of the strongest fighters is presented Greco-Roman style on a world of 2011 cup. Found out some tendencies and conformities to the law in application technical tactical actions by fighters in a competition duel on the modern stage of development to Greco-Roman fight. It is set that in most cases sportsmen won due to ability to win with insignificant advantage for all of competitors. They most adjusted to the modern requirements of conduct of duel, conduct an active fight and own effective attacking receptions, reliably they are applied and rarely attack without an estimation. One of more effective receptions in an orchestra there is defence of fighter which is down. Found out failings in preparation of the Ukrainian sportsmen can underlie correction of the programs of preparation to the Olympic games. It is recommended to utillize the resulted information for the design of the special trainings tasks which are conditioned the individual features of separate sportsmen.

  14. Promising silicones modified with cationic biocides for the development of antimicrobial medical devices.

    Science.gov (United States)

    Ghamrawi, Sarah; Bouchara, Jean-Philippe; Tarasyuk, Oksana; Rogalsky, Sergiy; Lyoshina, Lyudmila; Bulko, Olga; Bardeau, Jean-François

    2017-06-01

    We have tested silicones containing 2% or 5% of the cationic biocides polyhexamethylene guanidine dodecylbenzenesulfonate (PHMG-DBS), 1-octyl-3-methylimidazolium tetrafluoroborate (OMIM-BF 4 ) or 1-dodecyl-3-methylimidazolium tetrafluoroborate (DMIM-BF 4 ) against the major relevant bacterial and yeast species in health care-associated infections (HCAI). Study conducted according to the international standard ISO 22196 revealed that silicones containing 2% or 5% DMIM-BF 4 or 5% PHMG-DBS presented the highest antimicrobial activity, leading to a logarithmic growth reduction of 3.03 to 6.46 and 3.65 to 4.85 depending on the bacterial or fungal species. Heat-pretreated silicones containing 2% DMIM-BF 4 kept a high activity, with at least a 3-log reduction in bacterial growth, except against P. aeruginosa where there was only a 1.1-log reduction. After 33days, the release ratio of cationic biocide from silicone films containing 5% of DMIM-BF 4 was found to be 5.6% in pure water and 1.9% in physiological saline solution, respectively. No leaching of PHMG-DBS polymeric biocide was detected under the same conditions. These results demonstrate unambiguously that silicones containing 2% DMIM-BF 4 or 5% PHMG-DBS present high antimicrobial activity, as well as high leaching resistance and therefore may be good candidates for the development of safer medical devices. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Optimal scheduling of biocide dosing for seawater-cooled power and desalination plants

    KAUST Repository

    Mahfouz, Abdullah Bin

    2011-02-13

    Thermal desalination systems are typically integrated with power plants to exploit the excess heat resulting from the power-generation units. Using seawater in cooling the power plant and the desalination system is a common practice in many parts of the world where there is a shortage of freshwater. Biofouling is one of the major problems associated with the usage of seawater in cooling systems. Because of the dynamic variation in the power and water demands as well as the changes in the characteristics of seawater and the process, there is a need to develop an optimal policy for scheduling biocide usage and cleaning maintenance of the heat exchangers. The objective of this article is to introduce a systematic procedure for the optimization of scheduling the dosing of biocide and dechlorination chemicals as well as cleaning maintenance for a power production/thermal desalination plant. A multi-period optimization formulation is developed and solved to determine: the optimal levels of dosing and dechlorination chemicals; the timing of maintenance to clean the heat-exchange surfaces; and the dynamic dependence of the biofilm growth on the applied doses, the seawater-biocide chemistry, the process conditions, and seawater characteristics for each time period. The technical, economic, and environmental considerations of the system are accounted for. A case study is solved to elucidate the applicability of the developed optimization approach. © 2011 Springer-Verlag.

  16. Development of a biocidal treatment regime to inhibit biological growths on cultural heritage: BIODAM

    Science.gov (United States)

    Young, M. E.; Alakomi, H.-L.; Fortune, I.; Gorbushina, A. A.; Krumbein, W. E.; Maxwell, I.; McCullagh, C.; Robertson, P.; Saarela, M.; Valero, J.; Vendrell, M.

    2008-12-01

    Existing chemical treatments to prevent biological damage to monuments often involve considerable amounts of potentially dangerous and even poisonous biocides. The scientific approach described in this paper aims at a drastic reduction in the concentration of biocide applications by a polyphasic approach of biocides combined with cell permeabilisers, polysaccharide and pigment inhibitors and a photodynamic treatment. A variety of potential agents were screened to determine the most effective combination. Promising compounds were tested under laboratory conditions with cultures of rock deteriorating bacteria, algae, cyanobacteria and fungi. A subsequent field trial involved two sandstone types with natural biofilms. These were treated with multiple combinations of chemicals and exposed to three different climatic conditions. Although treatments proved successful in the laboratory, field trials were inconclusive and further testing will be required to determine the most effective treatment regime. While the most effective combination of chemicals and their application methodology is still being optimised, results to date indicate that this is a promising and effective treatment for the control of a wide variety of potentially damaging organisms colonising stone substrates.

  17. Biocide activity of Annona coriacea seeds extract on Rhodnius neglectus (Hemiptera: Reduviidae

    Directory of Open Access Journals (Sweden)

    Ângela Pinheiro Carneiro

    2013-03-01

    Full Text Available The use of synthetic insecticides for insect control may lead to different kind of problems, such as vector resistance to insecticides. To avoid these problems, a new research area to study botanical products as possible disease vectors controls, has become a feasible alternative. The purpose of this research was to evaluate the biocide activity of the ethanol extract of seeds of Annona coriacea on Rhodnius neglectus (Chagas disease vector nymphs and adults. For this, different concentrations extracts were evaluated: 25, 50, 100 and 200mg/ mL, and water in DMSO (20% was used as control. The experimental design was completely randomized and we conducted the bioassay with nymphs and adults, with 10 nymphs and 10 adults (five males and five females per treatment. Extract action was evaluated in both bioassays, in order to identify possible effects of mortality and life cycle interruption of nymphs and adults during a 28-day-period. The results obtained showed that the extract of A. coriacea was able to disrupt the development of nymphs and adults of R. neglectus, with a mortality rate of more than 90%, 36% and 100%, at the highest concentrations, respectively. There was also molting inhibition in nymphs, lower reproductive capacity in females, feeding deterrence and morphological changes in nymphs and adults. We concluded that the extract of A. coriacea has insecticide action on nymphs and adults of R. neglectus.La enfermedad de Chagas se convirtió en un problema de salud debido a su importancia epidemiológica, es producida por el protista Trypanosoma cruzi, cuyos insectos vectores son del género Triatoma y Panstrongylus. El objetivo de este estudio fue evaluar la actividad biocida del extracto de Annona coriacea en las ninfas de Rhodnius neglectus y en sus adultos. Se evaluaron 14 concentraciones de 25, 50, 100 y 200mg/ml del extracto etanólico, así como el control, en este caso agua de DMSO (20%. Se utilizo un diseño completamente

  18. Molecular Characterization of Reduced Susceptibility to Biocides in Clinical Isolates of Acinetobacter baumannii

    Directory of Open Access Journals (Sweden)

    Fei Lin

    2017-09-01

    Full Text Available Active efflux is regarded as a common mechanism for antibiotic and biocide resistance. However, the role of many drug efflux pumps in biocide resistance in Acinetobacter baumannii remains unknown. Using biocide-resistant A. baumannii clinical isolates, we investigated the incidence of 11 known/putative antimicrobial resistance efflux pump genes (adeB, adeG, adeJ, adeT1, adeT2, amvA, abeD, abeM, qacE, qacEΔ1, and aceI and triclosan target gene fabI through PCR and DNA sequencing. Reverse transcriptase quantitative PCR was conducted to assess the correlation between the efflux pump gene expression and the reduced susceptibility to triclosan or chlorhexidine. The A. baumannii isolates displayed high levels of reduced susceptibility to triclosan, chlorhexidine, benzalkonium, hydrogen peroxide, and ethanol. Most tested isolates were resistant to multiple antibiotics. Efflux resistance genes were widely distributed and generally expressed in A. baumannii. Although no clear relation was established between efflux pump gene expression and antibiotic resistance or reduced biocide susceptibility, triclosan non-susceptible isolates displayed relatively increased expression of adeB and adeJ whereas chlorhexidine non-susceptible isolates had increased abeM and fabI gene expression. Increased expression of adeJ and abeM was also demonstrated in multiple antibiotic resistant isolates. Exposure of isolates to subinhibitory concentrations of triclosan or chlorhexidine induced gene expression of adeB, adeG, adeJ and fabI, and adeB, respectively. A point mutation in FabI, Gly95Ser, was observed in only one triclosan-resistant isolate. Multiple sequence types with the major clone complex, CC92, were identified in high level triclosan-resistant isolates. Overall, this study showed the high prevalence of antibiotic and biocide resistance as well as the complexity of intertwined resistance mechanisms in clinical isolates of A. baumannii, which highlights the

  19. Comparative analysis of copper and zinc based agrichemical biocide products: materials characteristics, phytotoxicity and in vitro antimicrobial efficacy

    Directory of Open Access Journals (Sweden)

    Harikishan Kannan

    2016-07-01

    Full Text Available In the past few decades, copper based biocides have been extensively used in food crop protection including citrus, small fruits and in all garden vegetable production facilities. Continuous and rampant use of copper based biocides over decades has led to accumulation of this metal in the soil and the surrounding ecosystem. Toxic levels of copper and its derivatives in both the soil and in the run off pose serious environmental and public health concerns. Alternatives to copper are in great need for the agriculture industry to produce food crops with minimal environmental risks. A combination of copper and zinc metal containing biocide such as Nordox 30/30 or an improved version of zinc-only containing biocide would be a good alternative to copper-only products if the efficacy can be maintained. As of yet there is no published literature on the comparative study of the materials characteristics and phyto-compatibility properties of copper and zinc-based commercial products that would allow us to evaluate the advantages and disadvantages of both versions of pesticides. In this report, we compared copper hydroxide and zinc oxide based commercially available biocides along with suitable control materials to assess their efficacy as biocides. We present a detailed material characterization of the biocides including morphological studies involving electron microscopy, molecular structure studies involving X-ray diffraction, phytotoxicity studies in model plant (tomato and antimicrobial studies involving surrogate plant pathogens (Xanthomonas alfalfae subsp. citrumelonis, Pseudomonas syringae pv. syringae and Clavibacter michiganensis subsp. michiganensis. Zinc based compounds were found to possess comparable to superior antimicrobial properties while exhibiting significantly lower phytotoxicity when compared to copper based products thus suggesting their potential as an alternative.

  20. Comparative toxicological effects of two antifouling biocides on the marine diatom Chaetoceros lorenzianus: Damage and post-exposure recovery.

    Science.gov (United States)

    Chavan, Pooja; Kumar, Rajesh; Kirubagaran, Ramalingam; Venugopalan, Vayalam P

    2017-10-01

    Antifouling biocides are commonly used in coastal electric power stations to prevent biofouling in their condenser cooling systems. However, the environmental impact of the chemical biocides is less understood than the thermal stress effects caused by the condenser effluents. In this study, Chaetoceros lorenzianus, a representative marine diatom, was used to analyse the toxicity of two antifouling biocides, chlorine and chlorine dioxide. The diatom cells were subjected to a range of concentrations of the biocides (from 0.05 to 2mg/L, as total residual oxidants, TRO) for contact time of 30min. They were analysed for viability, genotoxicity, chlorophyll a and cell density endpoints. The cells were affected at all concentrations of the biocides (0.05-2mg/L), showing dose-dependent decrease in viability and increase in DNA damage. The treated cells were later incubated in filtered seawater devoid of biocide to check for recovery. The cells were able to recover in terms of overall viability and DNA damage, when they had been initially treated with low concentrations of the biocides (0.5mg/L of Cl 2 or 0.2mg/L of ClO 2 ). Chlorophyll a analysis showed irreparable damage at all concentrations, while cell density showed increasing trend of reduction, if treated above 0.5mg/L of Cl 2 and 0.2mg/L of ClO 2 . The data indicated that in C. lorenzianus, cumulative toxic effects and recovery potential of ClO 2 up to 0.2mg/L were comparable with those of Cl 2 , up to 0.5mg/L concentration in terms of the studied endpoints. The results indicate that at the biocide levels currently being used at power stations, recovery of the organism is feasible upon return to ambient environment. Similar studies should be carried out on other planktonic and benthic organisms, which will be helpful in the formulation of future guidelines for discharge of upcoming antifouling biocides such as chlorine dioxide. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. Characterizations of proper actions

    Science.gov (United States)

    Biller, Harald

    2004-03-01

    Three kinds of proper actions of increasing strength are defined. We prove that the three definitions specialize to the definitions by Bourbaki, by Palais and by Baum, Connes and Higson in their respective settings. The third of these, which thus turns out to be the strongest, originally only concerns actions of second countable locally compact groups on metrizable spaces. In this situation, it is shown to coincide with the other two definitions if the total space locally has the Lindelöf property and the orbit space is regular.

  2. Effects of single and repeated exposure to biocidal active substances on the barrier function of the skin in vitro.

    Science.gov (United States)

    Buist, Harrie E; van de Sandt, Johannes J M; van Burgsteden, Johan A; de Heer, Cees

    2005-10-01

    The dermal route of exposure is important in worker exposure to biocidal products. Many biocidal active substances which are used on a daily basis may decrease the barrier function of the skin to a larger extent than current risk assessment practice addresses, due to possible skin effects of repeated exposure. The influence of repeated and single exposure to representative biocidal active substances on the skin barrier was investigated in vitro. The biocidal active substances selected were alkyldimethylbenzylammonium chloride (ADBAC), boric acid, deltamethrin, dimethyldidecylammonium chloride (DDAC), formaldehyde, permethrin, piperonyl butoxide, sodium bromide, and tebuconazole. Of these nine compounds, only the quaternary ammonium chlorides ADBAC and DDAC had a clear and consistent influence on skin permeability of the marker compounds tritiated water and [(14)C]propoxur. For these compounds, repeated exposure increased skin permeability more than single exposure. At high concentrations the difference between single and repeated exposure was quantitatively significant: repeated exposure to 300 mg/L ADBAC increased skin permeability two to threefold in comparison to single exposure. Therefore, single and repeated exposure to specific biocidal products may significantly increase skin permeability, especially when used undiluted.

  3. The 100 strongest radio point sources in the field of the Large Magellanic Cloud at 1.4 GHz

    Directory of Open Access Journals (Sweden)

    Payne J.L.

    2009-01-01

    Full Text Available We present the 100 strongest 1.4 GHz point sources from a new mosaic image in the direction of the Large Magellanic Cloud (LMC. The observations making up the mosaic were made using Australia Telescope Compact Array (ATCA over a ten year period and were combined with Parkes single dish data at 1.4 GHz to complete the image for short spacing. An initial list of co-identifications within 1000 at 0.843, 4.8 and 8.6 GHz consisted of 2682 sources. Elimination of extended objects and artifact noise allowed the creation of a refined list containing 1988 point sources. Most of these are presumed to be background objects seen through the LMC; a small portion may represent compact H ii regions, young SNRs and radio planetary nebulae. For the 1988 point sources we find a preliminary average spectral index (α of -0.53 and present a 1.4 GHz image showing source location in the direction of the LMC.

  4. The 100 Strongest Radio Point Sources in the Field of the Large Magellanic Cloud at 1.4 GHz

    Directory of Open Access Journals (Sweden)

    Payne, J. L.

    2009-06-01

    Full Text Available We present the 100 strongest 1.4~GHz point sources from a new mosaicimage in the direction of the Large Magellanic Cloud (LMC. The observationsmaking up the mosaic were made using Australia Telescope Compact Array (ATCAover a ten year period and were combined with Parkes single dish data at 1.4 GHz to complete the image for short spacing. An initial list of co-identifications within 10arcsec at 0.843, 4.8 and 8.6 GHz consisted of 2682 sources. Elimination of extended objects and artifact noise allowed the creation of a refined list containing 1988 point sources. Most of these are presumed to be background objects seen through the LMC; a small portion may represent compact HII regions, young SNRs and radio planetary nebulae. For the 1988 point sources we find a preliminary average spectral index ($alpha$ of -0.53 and present a 1.4 GHz image showing source locationin the direction of the LMC.

  5. Perception and the strongest sensory memory trace of multi-stable displays both form shortly after the stimulus onset.

    Science.gov (United States)

    Pastukhov, Alexander

    2016-02-01

    We investigated the relation between perception and sensory memory of multi-stable structure-from-motion displays. The latter is an implicit visual memory that reflects a recent history of perceptual dominance and influences only the initial perception of multi-stable displays. First, we established the earliest time point when the direction of an illusory rotation can be reversed after the display onset (29-114 ms). Because our display manipulation did not bias perception towards a specific direction of illusory rotation but only signaled the change in motion, this means that the perceptual dominance was established no later than 29-114 ms after the stimulus onset. Second, we used orientation-selectivity of sensory memory to establish which display orientation produced the strongest memory trace and when this orientation was presented during the preceding prime interval (80-140 ms). Surprisingly, both estimates point towards the time interval immediately after the display onset, indicating that both perception and sensory memory form at approximately the same time. This suggests a tighter integration between perception and sensory memory than previously thought, warrants a reconsideration of its role in visual perception, and indicates that sensory memory could be a unique behavioral correlate of the earlier perceptual inference that can be studied post hoc.

  6. GAMMA BAND PLASTICITY IN SENSORY CORTEX IS A SIGNATURE OF THE STRONGEST MEMORY RATHER THAN MEMORY OF THE TRAINING STIMULUS

    Science.gov (United States)

    Weinberger, Norman M.; Miasnikov, Alexandre A.; Bieszczad, Kasia M.; Chen, Jemmy C.

    2013-01-01

    Gamma oscillations (~30–120 Hz) are considered to be a reflection of coordinated neuronal activity, linked to processes underlying synaptic integration and plasticity. Increases in gamma power within the cerebral cortex have been found during many cognitive processes such as attention, learning, memory and problem solving in both humans and animals. However, the specificity of gamma to the detailed contents of memory remains largely unknown. We investigated the relationship between learning-induced increased gamma power in the primary auditory cortex (A1) and the strength of memory for acoustic frequency. Adult male rats (n = 16) received three days (200 trials each) of pairing a tone (3.66 kHz) with stimulation of the nucleus basalis, which implanted a memory for acoustic frequency as assessed by associatively-induced disruption of ongoing behavior, viz., respiration. Post-training frequency generalization gradients (FGGs) revealed peaks at non-CS frequencies in 11/16 cases, likely reflecting normal variation in pre-training acoustic experiences. A stronger relationship was found between increased gamma power and the frequency with the strongest memory (peak of the difference between individual post- and pre-training FGGs) vs. behavioral responses to the CS training frequency. No such relationship was found for the theta/alpha band (4–15 Hz). These findings indicate that the strength of specific increased neuronal synchronization within primary sensory cortical fields can determine the specific contents of memory. PMID:23669065

  7. Gamma band plasticity in sensory cortex is a signature of the strongest memory rather than memory of the training stimulus.

    Science.gov (United States)

    Weinberger, Norman M; Miasnikov, Alexandre A; Bieszczad, Kasia M; Chen, Jemmy C

    2013-09-01

    Gamma oscillations (∼30-120Hz) are considered to be a reflection of coordinated neuronal activity, linked to processes underlying synaptic integration and plasticity. Increases in gamma power within the cerebral cortex have been found during many cognitive processes such as attention, learning, memory and problem solving in both humans and animals. However, the specificity of gamma to the detailed contents of memory remains largely unknown. We investigated the relationship between learning-induced increased gamma power in the primary auditory cortex (A1) and the strength of memory for acoustic frequency. Adult male rats (n=16) received three days (200 trials each) of pairing a tone (3.66 kHz) with stimulation of the nucleus basalis, which implanted a memory for acoustic frequency as assessed by associatively-induced disruption of ongoing behavior, viz., respiration. Post-training frequency generalization gradients (FGGs) revealed peaks at non-CS frequencies in 11/16 cases, likely reflecting normal variation in pre-training acoustic experiences. A stronger relationship was found between increased gamma power and the frequency with the strongest memory (peak of the difference between individual post- and pre-training FGGs) vs. behavioral responses to the CS training frequency. No such relationship was found for the theta/alpha band (4-15 Hz). These findings indicate that the strength of specific increased neuronal synchronization within primary sensory cortical fields can determine the specific contents of memory. Copyright © 2013 Elsevier Inc. All rights reserved.

  8. The dynamics of competitive activity performance of the strongest athletes in the world during the Olympic year

    Directory of Open Access Journals (Sweden)

    Rabin Muhammad Fahmi

    2016-12-01

    Full Text Available The paper scrutinizes the annual dynamics of competitive activity performance of prize winners in track and field of the Games of the XXXI Olympiad in Rio de Janeiro. The studies performed allow to identify two basic strategies of participation of elite athletes in the competitions. The first implies a strong focus on achieving the best results in major competitions of the year. It is used by most of the strongest athletes in the world. The second focuses the athlete on the effective combination of competitive activity in major competitions of the year (the Olympics and World Championships and in the Diamond League. As shown by the experience of the best sports practice, only a limited number of athletes manage to implement the latter strategy. The methodological approaches to planning competitive activity during the year are identified. The first involves the rational allocation of the optimal number of competitions throughout the year, the second focuses on preparatory competitive activities of a fairly high intensity, and the third involves the use of a small number of competitions in the system of annual training.

  9. Muscle quality and relative adiposity are the strongest predictors of lower-extremity physical function in older women.

    Science.gov (United States)

    Straight, Chad R; Brady, Anne O; Evans, Ellen M

    2015-01-01

    The aim of this study was to examine the relative contributions of physical activity, adiposity, lean mass and muscle quality to lower-extremity physical function (LEPF) in older women. Cross-sectional analysis at a university research laboratory. Community-dwelling older women (n=96, 73.9 ± 5.6 years, BMI=26.5 ± 4.7 kg/m(2)) were assessed for body composition via dual-energy X-ray absorptiometry, leg extension power using the Nottingham power rig, muscle quality (W/kg) as the ratio of leg extension power (W) to lower-body mineral free lean mass (kg) and moderate-intensity physical activity via questionnaire. A composite measure of LEPF was calculated by summing Z-scores of the 6-min walk, 8-foot up-and-go and 30-s chair stand tests. Muscle quality and physical activity were associated with all measures of LEPF (all p0.05). Hierarchical linear regression analyses revealed that muscle quality (standardized β=0.47, pquality and relative adiposity are the strongest independent predictors of LEPF in older women. These findings suggest that maintaining muscle quality, especially relative to adiposity, may be a critical target for interventions to prevent declines in physical function in older women. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  10. Evidence for the strongest version of the 4d a-theorem via a-maximization along RG flows

    International Nuclear Information System (INIS)

    Barnes, Edwin; Intriligator, Ken; Wecht, Brian; Wright, Jason

    2004-01-01

    In earlier work, we (KI and BW) gave a two line 'almost proof' (for supersymmetric RG flows) of the weakest form of the conjectured 4d a-theorem, that aIRaUV, using our result that the exact superconformal R-symmetry of 4d SCFTs maximizes a=3TrR3-TrR. The proof was incomplete because of two identified loopholes: theories with accidental symmetries, and the fact that it is only a local maximum of a. Here we discuss and extend a proposal of Kutasov (which helps close the latter loophole) in which a-maximization is generalized away from the endpoints of the RG flow, with Lagrange multipliers that are conjectured to be identified with the running coupling constants. a-maximization then yields a monotonically decreasing 'a-function' along the RG flow to the IR. As we discuss, this proposal in fact suggests the strongest version of the a-theorem: that 4d RG flows are gradient flows of an a-function, with positive-definite metric. In the perturbative limit, the RG flow metric thus obtained is shown to agree precisely with that found by very different computations by Osborn and collaborators. As examples, we discuss a new class of 4d SCFTs, along with their dual descriptions and IR phases, obtained from SQCD by coupling some of the flavors to added singlets

  11. Biocide Susceptibility of Staphylococcus aureus CC398 and CC30 Isolates from Pigs and Identification of the Biocide Resistance Genes, qacG and qacC

    DEFF Research Database (Denmark)

    Seier-Petersen, Maria Amalie; Nielsen, Lene Nørby; Ingmer, Hanne

    2015-01-01

    Objectives: Methicillin-resistant Staphylococcus aureus (MRSA), in particular clonal complex (CC) 398, is increasingly found in livestock. Recently, MRSA CC30 was identified in Danish pigs. We determined the susceptibility of porcine S. aureus isolates of CC398 and CC30 to disinfectants used in pig......)-encoding virulence factors were investigated. Methods: Susceptibilities to biocides and antimicrobial agents of 79 porcine S. aureus isolates were determined by the microdilution method. Isolates comprised 21 methicillin-sensitive S. aureus (MSSA) and 40 MRSA isolates belonging to CC398 and 13 MSSA and 5 MRSA...... isolates belonging to CC30. The presence of quaternary ammonium compound (QAC) resistance efflux pumps was analyzed using an ethidium bromide accumulation assay. The presence of qac resistance genes in active efflux pump positive isolates was determined by whole-genome sequencing data. All isolates were...

  12. Influence of growth media on the sensitivity of Staphylococcus aureus and Pseudomonas aeruginosa to cationic biocides.

    Science.gov (United States)

    Brill, Florian; Goroncy-Bermes, Peter; Sand, Wolfgang

    2006-01-01

    In this study, the influence of culturing Staphylococcus aureus and Pseudomonas aeruginosa under different growth conditions on their inactivation by the cationic active compounds benzalkonium chloride, chlorhexidine digluconate and octenidine dihydrochloride was investigated. Cells were grown in non-agitated tryptone soya broth as well as on tryptone soya agar according to national and international standards for evaluating chemical disinfectants. In quantitative suspension tests, cells of both test organisms grown on agar were significantly more sensitive to all three biocides than cells grown in broth. The differences in antimicrobial activity were greater in the case of S. aureus than in the case of P. aeruginosa. With S. aureus cultures, differences in the reduction factor of up to 5 log steps were found, with P. aeruginosa up to 2.5 log steps. The results of our uptake tests performed with S. aureus and octenidine dihydrochloride indicated that the growth conditions and the associated different stress factors either had an influence on the composition of the cell surface of this test organism or induced the formation of an efflux system. Cells of S. aureus cultured in broth took up only one-fifth of the amount of biocide molecules compared to cells from agar cultures. These data correlated with the results of the suspension tests. A low uptake of biocides apparently led to a reduced killing rate. In contrast to S. aureus, no significant differences in the uptake of octenidine dihydrochloride by cells of P. aeruginosa could be observed. These cells took up the same amount of the antimicrobial substance, whether on agar or in broth. In view of these results, possible consequences should be considered prior to changing test regulations.

  13. Biocide and corrosion inhibition use in the oil and gas industry: Effectiveness and potential environmental impacts

    International Nuclear Information System (INIS)

    Brandon, D.M.; Fillo, J.P.; Morris, A.E.; Evans, J.M.

    1995-01-01

    Treatment chemicals are used in all facets of the natural gas industry (NGI) from well development through transmission and storage of natural gas. The multitude of chemicals used, combined with the dozens of chemical manufacturers and/or suppliers has lead to the availability of hundreds of possible chemical products. Because of the widespread use of chemical products and their numerous sources, the NGI needs access to consistent data regarding their effectiveness and potential environmental impacts. The objective of this work was to evaluate the effectiveness and potential environmental impacts of, chemical products used in the NGI. This assessment was initially focused on biocides and corrosion inhibitors and their use in the gas production, storage and transmission facilities, The overall approach was obtain the necessary data on chemical use and effectiveness directly from the oil and gas industry, supplemented with data/information obtained from the published literature. Five case histories of chemical use were documented and evaluated to assess the effectiveness of these chemicals. Potential environmental impacts were addressed by performing a screening environmental assessment on the use of glutaraldehyde, a widely used biocide. Prototype discharge scenarios were formulated and modeled to evaluate potential impacts to groundwater and surface water. The paper describes the basis for the study, provides an overview of chemical use with a focus on biocides and corrosion inhibitors, describes and assesses the specific uses of chemicals, and presents the results of the environmental assessment. It was found that various chemicals can be effective in treating microbiologically influenced corrosion and souring, but that the effectiveness of specific chemicals is dependent on the operational scenario and the site-specific conditions

  14. New promising antifouling agent based on polymeric biocide polyhexamethylene guanidine molybdate.

    Science.gov (United States)

    Protasov, Alexander; Bardeau, Jean-Francois; Morozovskaya, Irina; Boretska, Mariia; Cherniavska, Tetiana; Petrus, Lyudmyla; Tarasyuk, Oksana; Metelytsia, Larisa; Kopernyk, Iryna; Kalashnikova, Larisa; Dzhuzha, Oleg; Rogalsky, Sergiy

    2017-09-01

    A new polymeric biocide polyhexamethylene guanidine (PHMG) molybdate has been synthesized. The obtained cationic polymer has limited water solubility of 0.015 g/100 mL and is insoluble in paint solvents. The results of acute toxicity studies indicate moderate toxicity of PHMG molybdate, which has a median lethal dose at 48 h of 0.7 mg/L for Daphnia magna and at 96 h of 17 mg/L for Danio rerio (zebrafish) freshwater model organisms. Commercial ship paint was then modified by the addition of a low concentration of polymeric biocide 5% (w/w). The painted steel panels were kept in Dnipro River water for the evaluation of the dynamics of fouling biomass. After 129-d exposure, Bryozoa dominated in biofouling of tested substrates, forming 86% (649 g/m 2 ) of the total biomass on control panel surfaces. However, considerably lower Bryozoa fouling biomass (15 g/m 2 ) was detected for coatings containing PHMG molybdate. Dreissenidae mollusks were found to form 88% (2182 g/m 2 ) of the fouling biomass on the control substrates after 228 d of exposure, whereas coatings containing PHMG molybdate showed a much lower biomass value of 23.6 g/m 2 . The leaching rate of PHMG molybdate in water was found to be similar to rates for conventional booster biocides ranging from 5.7 μg/cm 2 /d at the initial stage to 2.2 μg/cm 2 /d at steady state. Environ Toxicol Chem 2017;36:2543-2551. © 2017 SETAC. © 2017 SETAC.

  15. Biofilm Inhibition by Novel Natural Product- and Biocide-Containing Coatings Using High-Throughput Screening

    Directory of Open Access Journals (Sweden)

    Maria Salta

    2018-05-01

    Full Text Available The use of natural products (NPs as possible alternative biocidal compounds for use in antifouling coatings has been the focus of research over the past decades. Despite the importance of this field, the efficacy of a given NP against biofilm (mainly bacteria and diatoms formation is tested with the NP being in solution, while almost no studies test the effect of an NP once incorporated into a coating system. The development of a novel bioassay to assess the activity of NP-containing and biocide-containing coatings against marine biofilm formation has been achieved using a high-throughput microplate reader and highly sensitive confocal laser scanning microscopy (CLSM, as well as nucleic acid staining. Juglone, an isolated NP that has previously shown efficacy against bacterial attachment, was incorporated into a simple coating matrix. Biofilm formation over 48 h was assessed and compared against coatings containing the NP and the commonly used booster biocide, cuprous oxide. Leaching of the NP from the coating was quantified at two time points, 24 h and 48 h, showing evidence of both juglone and cuprous oxide being released. Results from the microplate reader showed that the NP coatings exhibited antifouling efficacy, significantly inhibiting biofilm formation when compared to the control coatings, while NP coatings and the cuprous oxide coatings performed equally well. CLSM results and COMSTAT analysis on biofilm 3D morphology showed comparable results when the NP coatings were tested against the controls, with higher biofilm biovolume and maximum thickness being found on the controls. This new method proved to be repeatable and insightful and we believe it is applicable in antifouling and other numerous applications where interactions between biofilm formation and surfaces is of interest.

  16. Antibiotics and common antibacterial biocides stimulate horizontal transfer of resistance at low concentrations.

    Science.gov (United States)

    Jutkina, J; Marathe, N P; Flach, C-F; Larsson, D G J

    2018-03-01

    There is a rising concern that antibiotics, and possibly other antimicrobial agents, can promote horizontal transfer of antibiotic resistance genes. For most types of antimicrobials their ability to induce conjugation below minimal inhibitory concentrations (MICs) is still unknown. Our aim was therefore to explore the potential of commonly used antibiotics and antibacterial biocides to induce horizontal transfer of antibiotic resistance. Effects of a wide range of sub-MIC concentrations of the antibiotics cefotaxime, ciprofloxacin, gentamicin, erythromycin, sulfamethoxazole, trimethoprim and the antibacterial biocides chlorhexidine digluconate, hexadecyltrimethylammoniumchloride and triclosan were investigated using a previously optimized culture-based assay with a complex bacterial community as a donor of mobile resistance elements and a traceable Escherichia coli strain as a recipient. Chlorhexidine (24.4μg/L), triclosan (0.1mg/L), gentamicin (0.1mg/L) and sulfamethoxazole (1mg/L) significantly increased the frequencies of transfer of antibiotic resistance whereas similar effects were not observed for any other tested antimicrobial compounds. This corresponds to 200 times below the MIC of the recipient for chlorhexidine, 1/20 of the MIC for triclosan, 1/16 of the MIC for sulfamethoxazole and right below the MIC for gentamicin. To our best knowledge, this is the first study showing that triclosan and chlorhexidine could stimulate the horizontal transfer of antibiotic resistance. Together with recent research showing that tetracycline is a potent inducer of conjugation, our results indicate that several antimicrobials including both common antibiotics and antibacterial biocides at low concentrations could contribute to antibiotic resistance development by facilitating the spread of antibiotic resistance between bacteria. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Seasonal influenza vaccination is the strongest correlate of cross-reactive antibody responses in migratory bird handlers.

    Science.gov (United States)

    Oshansky, Christine M; Wong, Sook-San; Jeevan, Trushar; Smallwood, Heather S; Webby, Richard J; Shafir, Shira C; Thomas, Paul G

    2014-12-09

    Avian species are reservoirs of influenza A viruses and could harbor viruses with significant pandemic potential. We examined the antibody and cellular immune responses to influenza A viruses in field or laboratory workers with a spectrum of occupational exposure to avian species for evidence of zoonotic infections. We measured the seroprevalence and T cell responses among 95 individuals with various types and degrees of prior field or laboratory occupational exposure to wild North American avian species using whole blood samples collected in 2010. Plasma samples were tested using endpoint enzyme-linked immunosorbent assay (ELISA) and hemagglutination (HA) inhibition (HAI) assays to subtypes H3, H4, H5, H6, H7, H8, and H12 proteins. Detectable antibodies were found against influenza HA antigens in 77% of individuals, while 65% of individuals tested had measurable T cell responses (gamma interferon [IFN-γ] enzyme-linked immunosorbent spot assay [ELISPOT]) to multiple HA antigens of avian origin. To begin defining the observed antibody specificities, Spearman rank correlation analysis showed that ELISA responses, which measure both head- and stalk-binding antibodies, do not predict HAI reactivities, which measure primarily head-binding antibodies. This result suggests that ELISA titers can report cross-reactivity based on the levels of non-head-binding responses. However, the strongest positive correlate of HA-specific ELISA antibody titers was receipt of seasonal influenza virus vaccination. Occupational exposure was largely uncorrelated with serological measures, with the exception of individuals exposed to poultry, who had higher levels of H7-specific antibodies than non-poultry-exposed individuals. While the cohort had antibody and T cell reactivity to a broad range of influenza viruses, only occupational exposure to poultry was associated with a significant difference in antibody levels to a specific subtype (H7). There was no evidence that T cell assays

  18. Biocides in urban wastewater treatment plant influent at dry and wet weather: concentrations, mass flows and possible sources

    DEFF Research Database (Denmark)

    Bollmann, Ulla E.; Petersen, Camilla Tang; Eriksson, Eva

    2014-01-01

    in Denmark and Sweden during dry and wet weather. It was discovered, that biocides are detectable not only during wet weather but also during dry weather when leaching from façade coatings can be excluded as source. In most cases, the concentrations during dry weather were in the same range as during wet...... to 116 mg h(-1) carbendazim or 73 mg h(-1) mecoprop) supporting the hypothesis that the biocides were washed off by wind driven rain. Contrary, the biocide emissions during dry weather were rather related to household activities than with emissions from buildings, i.e., emissions were highest during...... morning and evening hours (up to 50 mg h(-1)). Emissions during night were significantly lower than during daytime. Only for propiconazole a different emission behaviour during dry weather was observed: the mass load peaked in the late afternoon (3 g h(-1)) and declined slowly afterwards. Most likely...

  19. "My Voice Is Definitely Strongest in Online Communities": Students Using Social Media for Queer and Disability Identity-Making

    Science.gov (United States)

    Miller, Ryan A.

    2017-01-01

    In this qualitative study I explored the social media activities of 25 lesbian, gay, bisexual, transgender, and queer students with disabilities at a research-intensive university. Using a framework of identity-making that accounts for students' reflections, narrations, and actions, I detail students' experiences exploring queer/ disability…

  20. Evaluation of the potential of ozone as a power plant biocide

    Energy Technology Data Exchange (ETDEWEB)

    Mattice, J.S.; Trabalka, J.R.; Adams, S.M.; Faust, R.A.; Jolley, R.L.

    1978-09-01

    A review of the literature on the chemistry and biological effects of ozone was conducted to evaluate the potential of ozone to function as a power plant biocide. Evaluation of this potential is dependent upon determining the ability of ozone to maintain the integrity of both the condenser cooling system and the associated ecosystem. The well-known bactericidal capacity of ozone and the limited biofouling control studies conducted thus far suggest that ozone can control both slime and macroinvertebrate fouling at power plants. However, full-scale demonstrations of the minimum levels of ozone required and of solution of the practical aspects of application have not been performed.

  1. Kinetics of dissolution of a biocide soda-lime glass powder containing silver nanoparticles

    International Nuclear Information System (INIS)

    Esteban-Tejeda, L.; Silva, A. C. da; Mello-Castanho, S. R.; Pacharroman, C.; Moya, J. S.

    2013-01-01

    In the present study we have studied the lixiviation kinetics of silver nanoparticles, as well as the solubility of a particulate system ( 2 lixiviation followed a Jander model (α 2 /4 ≈ Kt). It has been proven that nanostructured soda-lime glass/nAg composed by particles <30 μm with a 20 wt% of silver are a strong biocide versus Gram-positive, Gram-negative bacteria and yeasts. This soda-lime glass/nAg acts as a perfect dispenser of silver nanoparticles to the liquid media, avoiding the fast increasing of its concentration over the toxicity limit for human cells and for the environment.

  2. Distribution of anti fouling biocides in coastal seawater of Egadi Islands

    International Nuclear Information System (INIS)

    Massanisso, Paolo; Ubaldi, Carla; Chiavarini, Salvatore; Pezza, Massimo; Cannarsa, Sigfrido; Bordone, Andrea

    2015-01-01

    The pollution level due to anti fouling biocides in the Marine Protected Area of Egadi Islands (MPA) has been evaluated by both grab and passive sampling. Analyses of tributyltin (TBT), diuron, irgarol, chlorothalonil and dichlofluanid have been carried out on seawater and sediments. The results indicate a good condition of the coastline, but further studies with passive sampling for TBT are required to help the MPA administrators to control the status of the seawater with a methodology suitable to reach the Environmental Quality Standard values established by the Water Framework Directive [it

  3. Hemoglobin to Hematocrit Ratio: The Strongest Predictor of Femoral Head Osteonecrosis in Children With Sickle Cell Disease.

    Science.gov (United States)

    Worrall, Douglas; Smith-Whitley, Kim; Wells, Lawrence

    2016-03-01

    Femoral head osteonecrosis (ON) secondary to sickle cell disease (SCD) often progresses to femoral head collapse, requiring total hip arthroplasty. However, this treatment has a limited durability and patients with SCD have higher rates of complications, requiring multiple revision operations. Identifying risk factors linked to ON in SCD can facilitate earlier precollapse diagnosis and surgical treatment aimed at preservation of the native hip joint. Fifty-nine children treated at our institution between January 2001 and April 2012 with SCD and ON, as diagnosed by magnetic resonance imaging or radiographic imaging, were compared with age-matched and sickle cell phenotype-matched (SS, SC, Sβ, Sβ) controls with no evidence of ON. Two sided t-tests assuming unequal variances determined statistically risk factors and threshold values were assigned to calculate odds ratios. Systolic blood pressure (P=1.2×10, OR=3.68), diastolic blood pressure (P=0.0084, OR=1.41), weight in the SCD-SS population (P=0.04, OR=1.85), and hemoglobin (Hb) in the SCD-SS population (P=0.036, OR=2.56) were elevated in cases. Curiously, dividing the Hb by the hematocrit to serve as a clinical proxy for the mean corpuscular Hb concentration (MCHC) produced an excellent predictor of ON (P=2.06×10, OR=5.17), which was especially pronounced in the SCD-SS subpopulation (P=2.28×10, OR=8.65). Among children with SCD, the overall prevalence of ON was 9% (59/658) and the phenotype with the highest prevalence of ON was Sβ thalassemia with an ON prevalence of 11.1%. There was no observed correlation between ON and height, body mass index, cholesterol, mean corpuscular volume, hematocrit, or glucocorticoid use. These data support a novel clinical marker, the MCHC proxy, as the strongest predictor of ON in children with SCD. High-risk children should receive hip magnetic resonance imaging to diagnose early ON and facilitate interventions focused on hip preservation, forestalling, or possibly preventing

  4. Analysis and imaging of biocidal agrochemicals using ToF-SIMS.

    Science.gov (United States)

    Converso, Valerio; Fearn, Sarah; Ware, Ecaterina; McPhail, David S; Flemming, Anthony J; Bundy, Jacob G

    2017-09-06

    ToF-SIMS has been increasingly widely used in recent years to look at biological matrices, in particular for biomedical research, although there is still a lot of development needed to maximise the value of this technique in the life sciences. The main issue for biological matrices is the complexity of the mass spectra and therefore the difficulty to specifically and precisely detect analytes in the biological sample. Here we evaluated the use of ToF-SIMS in the agrochemical field, which remains a largely unexplored area for this technique. We profiled a large number of biocidal active ingredients (herbicides, fungicides, and insecticides); we then selected fludioxonil, a halogenated fungicide, as a model compound for more detailed study, including the effect of co-occurring biomolecules on detection limits. There was a wide range of sensitivity of the ToF-SIMS for the different active ingredient compounds, but fludioxonil was readily detected in real-world samples (wheat seeds coated with a commercial formulation). Fludioxonil did not penetrate the seed to any great depth, but was largely restricted to a layer coating the seed surface. ToF-SIMS has clear potential as a tool for not only detecting biocides in biological samples, but also mapping their distribution.

  5. Green biocides, a promising technology: current and future applications to industry and industrial processes.

    Science.gov (United States)

    Ashraf, Muhammad Aqeel; Ullah, Saleem; Ahmad, Irshad; Qureshi, Ahmad Kaleem; Balkhair, Khaled S; Abdur Rehman, Muhammad

    2014-02-01

    The study of biofilms has skyrocketed in recent years due to increased awareness of the pervasiveness and impact of biofilms. It costs the USA literally billions of dollars every year in energy losses, equipment damage, product contamination and medical infections. But biofilms also offer huge potential for cleaning up hazardous waste sites, filtering municipal and industrial water and wastewater, and forming biobarriers to protect soil and groundwater from contamination. The complexity of biofilm activity and behavior requires research contributions from many disciplines such as biochemistry, engineering, mathematics and microbiology. The aim of this review is to provide a comprehensive analysis of emerging novel antimicrobial techniques, including those using myriad organic and inorganic products as well as genetic engineering techniques, the use of coordination complex molecules, composite materials and antimicrobial peptides and the use of lasers as such or their modified use in combination treatments. This review also addresses advanced and recent modifications, including methodological changes, and biocide efficacy enhancing strategies. This review will provide future planners of biofilm control technologies with a broad understanding and perspective on the use of biocides in the field of green developments for a sustainable future. © 2013 Society of Chemical Industry.

  6. Benzalkonium runoff from roofs treated with biocide products - In situ pilot-scale study.

    Science.gov (United States)

    Gromaire, M C; Van de Voorde, A; Lorgeoux, C; Chebbo, G

    2015-09-15

    Roof maintenance practices often involve the application of biocide products to fight against moss, lichens and algae. The main component of these products is benzalkonium chloride, a mixture of alkyl benzyl dimethyl ammonium chlorides with mainly C12 and C14 alkyl chain lengths, which is toxic for the aquatic environment. This paper describes, on the basis of an in-situ pilot scale study, the evolution of roof runoff contamination over a one year period following the biocide treatment of roof frames. Results show a major contamination of roof runoff immediately after treatment (from 5 to 30 mg/L), followed by an exponential decrease. 175-375 mm of cumulated rainfall is needed before the runoff concentrations become less than EC50 values for fish (280 μg/l). The residual concentration in the runoff water remains above 4 μg/L even after 640 mm of rainfall. The level of benzalkonium ions leaching depends on the roofing material, with lower concentrations and total mass leached from ceramic tiles than from concrete tiles, and on the state of the tile (new or worn out). Mass balance calculations indicate that a large part of the mass of benzalkonium compounds applied to the tiles is lost, probably due to biodegradation processes. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. EU Regulation of Nanobiocides: Challenges in Implementing the Biocidal Product Regulation (BPR

    Directory of Open Access Journals (Sweden)

    Anna Brinch

    2016-02-01

    Full Text Available The Biocidal Products Regulation (BPR contains several provisions for nanomaterials (NMs and is the first regulation in the European Union to require specific testing and risk assessment for the NM form of a biocidal substance as a part of the information requirements. Ecotoxicological data are one of the pillars of the information requirements in the BPR, but there are currently no standard test guidelines for the ecotoxicity testing of NMs. The overall objective of this work was to investigate the implications of the introduction of nano-specific testing requirements in the BPR and to explore how these might be fulfilled in the case of copper oxide nanoparticles. While there is information and data available in the open literature that could be used to fulfill the BPR information requirements, most of the studies do not take the Organisation for Economic Co-operation and Development’s nanospecific test guidelines into consideration. This makes it difficult for companies as well as regulators to fulfill the BPR information requirements for nanomaterials. In order to enable a nanospecific risk assessment, best practices need to be developed regarding stock suspension preparation and characterization, exposure suspensions preparation, and for conducting ecotoxicological test.

  8. EU Regulation of Nanobiocides: Challenges in Implementing the Biocidal Product Regulation (BPR).

    Science.gov (United States)

    Brinch, Anna; Hansen, Steffen Foss; Hartmann, Nanna B; Baun, Anders

    2016-02-16

    The Biocidal Products Regulation (BPR) contains several provisions for nanomaterials (NMs) and is the first regulation in the European Union to require specific testing and risk assessment for the NM form of a biocidal substance as a part of the information requirements. Ecotoxicological data are one of the pillars of the information requirements in the BPR, but there are currently no standard test guidelines for the ecotoxicity testing of NMs. The overall objective of this work was to investigate the implications of the introduction of nano-specific testing requirements in the BPR and to explore how these might be fulfilled in the case of copper oxide nanoparticles. While there is information and data available in the open literature that could be used to fulfill the BPR information requirements, most of the studies do not take the Organisation for Economic Co-operation and Development's nanospecific test guidelines into consideration. This makes it difficult for companies as well as regulators to fulfill the BPR information requirements for nanomaterials. In order to enable a nanospecific risk assessment, best practices need to be developed regarding stock suspension preparation and characterization, exposure suspensions preparation, and for conducting ecotoxicological test.

  9. Surface-attached cells, biofilms and biocide susceptibility: implications for hospital cleaning and disinfection.

    Science.gov (United States)

    Otter, J A; Vickery, K; Walker, J T; deLancey Pulcini, E; Stoodley, P; Goldenberg, S D; Salkeld, J A G; Chewins, J; Yezli, S; Edgeworth, J D

    2015-01-01

    Microbes tend to attach to available surfaces and readily form biofilms, which is problematic in healthcare settings. Biofilms are traditionally associated with wet or damp surfaces such as indwelling medical devices and tubing on medical equipment. However, microbes can survive for extended periods in a desiccated state on dry hospital surfaces, and biofilms have recently been discovered on dry hospital surfaces. Microbes attached to surfaces and in biofilms are less susceptible to biocides, antibiotics and physical stress. Thus, surface attachment and/or biofilm formation may explain how vegetative bacteria can survive on surfaces for weeks to months (or more), interfere with attempts to recover microbes through environmental sampling, and provide a mixed bacterial population for the horizontal transfer of resistance genes. The capacity of existing detergent formulations and disinfectants to disrupt biofilms may have an important and previously unrecognized role in determining their effectiveness in the field, which should be reflected in testing standards. There is a need for further research to elucidate the nature and physiology of microbes on dry hospital surfaces, specifically the prevalence and composition of biofilms. This will inform new approaches to hospital cleaning and disinfection, including novel surfaces that reduce microbial attachment and improve microbial detachment, and methods to augment the activity of biocides against surface-attached microbes such as bacteriophages and antimicrobial peptides. Future strategies to address environmental contamination on hospital surfaces should consider the presence of microbes attached to surfaces, including biofilms. Copyright © 2014 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

  10. Eficacia de algunos biocidas contra estafilococos hospitalarios sensibles y resistentes a la meticilina en la provincia de Buenos Aires, Argentina Efficacy of biocides against hospital isolates of Staphylococcus sensitive and resistant to methicillin, in the province of Buenos Aires, Argentina

    Directory of Open Access Journals (Sweden)

    Mirta Beatriz Reynaldo

    2004-09-01

    ímicos contra los microorganismos que han sido expuestos a antibióticos.OBJECTIVE: To assess the response to the action of different antiseptics and disinfectants usually used in Argentinian hospitals of hospital staphylococci sensitive and resistant to methicillin. To test the effectiveness of the biocides by measuring their effective bactericidal concentrations, and to determine whether there is any correlation between biocide resistance and methicillin resistance in this bacterial population. METHODS: The action of seven biocides was tested against 25 strains of nosocomial Staphylococcus spp. sensitive and resistant to methicillin, and in Staphylococcus aureus ATCC 6538. Hospital strains were obtained from April, 2000 to May, 2002, from clinical samples (blood culture, urine culture, catheter tip or abscess from male and female inpatients and outpatients at two tertiary hospitals. After isolation, antibiotic sensitivity was tested with the agar diffusion method of Kirby and Bauer. The action of hospital biocides on the strains was studied with the Kelsey-Sykes test, which establishes the effective bactericide concentrations of these compounds. RESULTS: The results showed that the response of strains sensitive and resistant to methicillin varied in comparison to the collection strain. Chlorhexidine digluconate, povidone iodine, weak tincture of iodine and alkaline glutaraldehyde were effective against most strains, regardless of whether they were sensitive or resistant to methicillin. CONCLUSIONS: We found no indication of a relationship between resistance to methicillin and resistance to biocides. Our study shows that further research is needed to evaluate the efficacy of chemical agents against microorganisms that have been exposed to antibiotic therapies.

  11. Determination of biocides as well as some biocide metabolites from facade run-off waters by solid phase extraction and high performance liquid chromatographic separation and tandem mass spectrometry detection.

    Science.gov (United States)

    Bester, K; Lamani, X

    2010-08-06

    Biocides are used to protect buildings, boats, and other materials from microbial infestations. A huge variety of compounds are being used: isothiazolinones, e.g., to prevent bacterial growth in paints, triazines and phenylureas against algal growth on water exposed materials while carbamates are used against fungal investations. However these biocides can be leached from the respective materials. As these are very effective compounds it is important to know the concentrations of these biocides in the leachates as well as their leaching behaviour to assess their risk to the environment. In this study, a method for the determination of biocides from facade material run-off water by means of high performance liquid chromatography coupled to tandem mass spectrometry (HPLC-MS/MS) was developed. Due to the amphiphilic character and the expected varying pH-values in the samples, the extractions as well as the HPLC-method development proved to be demanding. The water samples (leachates) were buffered with a phosphate buffer to pH 7. As some of the biocides are very hydrophilic, different SPE cartridges were tested to identify the SPE material with the highest recovery rates for all compounds. For gaining a good separation, analyte trapping was performed on the HPLC column. Quantification was performed using a mass spectrometer in multi-reaction monitoring with two transitions per compound. The final recovery rates were conducted using a cartridge with a divenylbenzyl polymer sorbent. A combination of methanol and acetonitrile as eluents was used to reach recovery rates in the range of 70-100%. The limit of quantification for the compounds of interest ranged from 0.01 to 0.1 microg/L. Copyright 2010 Elsevier B.V. All rights reserved.

  12. Arbuscular mycorrhizal inoculation following biocide treatment improves Calocedrus decurrens survival and growth in nursery and outplanting sites

    Science.gov (United States)

    Michael Amaranthus; David Steinfeld

    2005-01-01

    Commercial production of tree seedlings often includes various biocidal soil treatments for disease control. Such treatments can be effective in eliminating or reducing disease organisms in the soil, but may also eliminate non-targeted beneficial soil organisms, such as mycorrhizal fungi, that improve seedling performance, both in the nursery as well as the outplanted...

  13. Development of a concept for the environmental risk assessment of biocidal products for authorization purposes (BIOEXPO). Executive summary

    NARCIS (Netherlands)

    Dokkum, H.P. van; Scholten, M.C.Th.; Bakker, D.J.

    1998-01-01

    The Biocidal Products Directive (Draft 97/C69/03; latest version December 12' 1997, 95/0465 (COD); PE CONS 3633/97) will complete the European chemicals regulation, which consists of the directives on existing substances (Council regu-lation 793/93), new substances (Directive 92/32/EC) and

  14. COMPOSITE MATERIALS BASED ON ZINC SULFIDE AND ZINC OXIDE: STRUCTURAL AND BIOCIDAL PROPERTIES

    Directory of Open Access Journals (Sweden)

    Sukhodub L.B

    2016-12-01

    Full Text Available Introduction. The widespread use of drugs with antimicrobial action has led to the formation of microorganism resistance against wide range of antibiotics. One of the approaches to dissolving this problem is the substances modification by inorganic bioactive ions in oder to initiate a controlled reaction in the bone tissues and provision of antimicrobial activity. It is known that ZnO-based materials have a pronounced biocompatibility, they are characterized by high limit strength, absolute mechanical hardness, as well as the ability to withstand the harsh operating conditions. The aim of this work is the study of structural and biocidal properties of composite material based on zinc oxide and zinc sulfide (ZnS-ZnO and its complex with an organic substance - sodium alginate (ZnS-ZnO-Alg for use in biomedical purpose. Materials and methods. For the synthesis of ZnS-ZnO composite 50 ml 0.2M solution zinc nitrate was added to the 50 ml 0.2M thiourea CS (NH ₂ ₂ solution and stirred in a shaker for 60 minutes. The formation of the compound took place when added to a mixture of 25 mas.% solution of ammonia with the subsequent heating at 80 oC for 30 minutes. Synthesis of the metalorganic complex of ZnS-ZnO-Alg was performed by above mentioned procedure, but to the thiourea solution was previously added 1 ml of 3 mas.% solution of sodium alginate under ultrasonic mixing.. For the next research composites were dried or lyophilized. Study of antibacterial activity of the ZnS-ZnO and ZnS-ZnO-Alg particles was carried out with the use of nutrient mediums: Muller Hinton, meat-pepton nutrient (MPN. As the reference cultures were used E. coli ATCC 25922, S. aureus ATCC 25923, S. aureus ATSS 29213, S. aureus ATSS-6538, C albicans ATCC 885-653. Determination of the minimum bactericidal concentration (MBC was carried out by a modified serial diluted method in liquid nutrient broth followed plating on solid Muller Hinton nutrient medium. In addition, the

  15. Relationship of Triamine-Biocide Tolerance of Salmonella enterica Serovar Senftenberg to Antimicrobial Susceptibility, Serum Resistance and Outer Membrane Proteins.

    Science.gov (United States)

    Futoma-Kołoch, Bożena; Dudek, Bartłomiej; Kapczyńska, Katarzyna; Krzyżewska, Eva; Wańczyk, Martyna; Korzekwa, Kamila; Rybka, Jacek; Klausa, Elżbieta; Bugla-Płoskońska, Gabriela

    2017-07-11

    A new emerging phenomenon is the association between the incorrect use of biocides in the process of disinfection in farms and the emergence of cross-resistance in Salmonella populations. Adaptation of the microorganisms to the sub-inhibitory concentrations of the disinfectants is not clear, but may result in an increase of sensitivity or resistance to antibiotics, depending on the biocide used and the challenged Salmonella serovar. Exposure of five Salmonella enterica subsp. enterica serovar Senftenberg ( S. Senftenberg) strains to triamine-containing disinfectant did not result in variants with resistance to antibiotics, but has changed their susceptibility to normal human serum (NHS). Three biocide variants developed reduced sensitivity to NHS in comparison to the sensitive parental strains, while two isolates lost their resistance to serum. For S. Senftenberg, which exhibited the highest triamine tolerance (6 × MIC) and intrinsic sensitivity to 22.5% and 45% NHS, a downregulation of flagellin and enolase has been demonstrated, which might suggest a lower adhesion and virulence of the bacteria. This is the first report demonstrating the influence of biocide tolerance on NHS resistance. In conclusion, there was a potential in S. Senftenberg to adjust to the conditions, where the biocide containing triamine was present. However, the adaptation did not result in the increase of antibiotic resistance, but manifested in changes within outer membrane proteins' patterns. The strategy of bacterial membrane proteins' analysis provides an opportunity to adjust the ways of infection treatments, especially when it is connected to the life-threating bacteremia caused by Salmonella species.

  16. Evaluation of biocidal efficacy of copper alloy coatings in comparison with solid metal surfaces: generation of organic copper phosphate nanoflowers.

    Science.gov (United States)

    Gutierrez, H; Portman, T; Pershin, V; Ringuette, M

    2013-03-01

    To analyse the biocidal efficacy of thermal sprayed copper surfaces. Copper alloy sheet metals containing >60% copper have been shown to exhibit potent biocidal activity. Surface biocidal activity was assessed by epifluorescence microscopy. After 2-h exposure at 20 °C in phosphate-buffered saline (PBS), contact killing of Gram-negative Escherichia coli and Gram-positive Staphylococcus epidermidis by brass sheet metal and phosphor bronze was 3-4-times higher than that by stainless steel. SEM observations revealed that the surface membranes of both bacterial strains were slightly more irregular when exposed to brass sheet metal than stainless steel. However, when exposed to phosphor bronze coating, E. coli were 3-4 times larger with irregular membrane morphology. In addition, the majority of the cells were associated with spherical carbon-copper-phosphate crystalline nanostructures characteristic of nanoflowers. The membranes of many of the S. epidermidis exhibited blebbing, and a small subset was also associated with nanoflowers. Our data indicate that increasing the surface roughness of copper alloys had a pronounced impact on the membrane integrity of Gram-positive and, to a lesser degree, Gram-negative bacteria. In the presence of PBS, carbon-copper-phosphate-containing nanoflowers were formed, likely nucleated by components derived from killed bacteria. The intimate association of the bacteria with the nanoflowers and phosphor bronze coating likely contributed to their nonreversible adhesion. Thermal spraying of copper alloys provides a strategy for the rapid coating of three-dimensional organic and inorganic surfaces with biocidal copper alloys. Our study demonstrates that the macroscale surface roughness generated by the thermal spray process enhances the biocidal activity of copper alloys compared with the nanoscale surface roughness of copper sheet metals. Moreover, the coating surface topography provides conditions for the rapid formation of organic copper

  17. Occurrence of imidacloprid, carbendazim, and other biocides in Italian house dust: Potential relevance for intakes in children and pets.

    Science.gov (United States)

    Salis, Severyn; Testa, Cecilia; Roncada, Paola; Armorini, Sara; Rubattu, Nicola; Ferrari, Angelo; Miniero, Roberto; Brambilla, Gianfranco

    2017-09-02

    The occurrence of pesticides intended for non-agricultural use was investigated in 206 dust samples drawn from vacuum-cleaner bags from residential flats in Italy. The multi-residue analysis targeted on 95 different active principles was performed with UPLC-MS/MS, with a Limit of Quantification (LOQ) of 0.008 μg/g dry weight. The results indicated the presence of imidacloprid (IMI) and carbendazim (CARB) in 30% and 26% of the samples, with a mean and P95 concentration between 1.6 and 39 and between 0.08 and 4.9 μg/g, respectively. Combined presence of two biocides was noted in 19.4% samples, of three biocides in 9.2% samples, of four biocides in 3.4% samples, and of five and six biocides in 0.5% and 1% samples, respectively. According to the estimated dust intake in infants/toddlers aged 6-24 months (16-100 mg d -1 ) and cats (200 mg d -1 ), it was possible to obtain risk characterization with respect to the Acceptable Daily Intake (ADI) for IMI of 0.060 mg/kg body weight (bw) proposed by the European Food Safety Authority (EFSA) and the chronic Population Adjusted Dose (cPAD) of 0.019 mg/kg bw d -1 by US-EPA. Under the worst-case scenario, the presence of IMI in dust indicates potential exceedance of the cPAD in kittens, to be considered as sentinel also accounting for combined exposure. This study highlights the relevance of consumer empowerment about the responsible use of pesticides as biocidal products in indoor environment.

  18. The Evaluation of the Products Examined within the Scope of the Market Surveillance and Inspection of Biocidal Product in the City of Çorum

    OpenAIRE

    Yapar, Zafer; Terzi, Özlem; Türkmen, Elif Nur

    2015-01-01

    Objective: In this study, it was aimed that the variety of the products examined within the scope of the market surveillance of biocidal products performed. Method: In this study planned to be of a descriptive nature, the data were obtained through a retrospective examination of the biocidal product inspection forms filled out in the City of Çorum within the scope of the Legislation of Biocidal Products dated 2013-14. Findings: In the course of the studies performed, it was determined that an...

  19. Heart and/or soul : reality and fiction in the association between the two strongest contributors to the global burden of disease - ischemic heart disease and depression

    NARCIS (Netherlands)

    de Jonge, Peter

    Depression and heart disease are the strongest contributors to the global burden of disease and are often intertwined: depression is a risk factor for heart disease and vice versa. Moreover, depression in patients with established heart disease is associated with cardiovascular disease progression.

  20. Encapsulation of Antifouling Organic Biocides in Poly(lactic acid) Nanoparticles

    Science.gov (United States)

    Kamtsikakis, Aristotelis; Kavetsou, Eleni; Chronaki, Konstantina; Kiosidou, Evangelia; Pavlatou, Evangelia; Karana, Alexandra; Papaspyrides, Constantine; Detsi, Anastasia; Karantonis, Antonis; Vouyiouka, Stamatina

    2017-01-01

    The scope of the current research was to assess the feasibility of encapsulating three commercial antifouling compounds, Irgarol 1051, Econea and Zinc pyrithione, in biodegradable poly(lactic acid) (PLA) nanoparticles. The emulsification–solvent evaporation technique was herein utilized to manufacture nanoparticles with a biocide:polymer ratio of 40%. The loaded nanoparticles were analyzed for their size and size distribution, zeta potential, encapsulation efficiency and thermal properties, while the relevant physicochemical characteristics were correlated to biocide–polymer system. In addition, the encapsulation process was scaled up and the prepared nanoparticles were dispersed in a water-based antifouling paint in order to examine the viability of incorporating nanoparticles in such coatings. Metallic specimens were coated with the nanoparticles-containing paint and examined regarding surface morphology. PMID:28952560

  1. Sodium lauryl sulfate - a biocide for controlling acidity development in bulk commercially formed solid elemental sulfur

    Energy Technology Data Exchange (ETDEWEB)

    Hyne, J. B. [Calgary Univ., AB (Canada). Dept. of Biological Sciences

    1996-04-01

    Acidification of bulk elemental sulfur caused by Thiobacillus species which consume elemental sulfur by converting it into oxidized sulfur forms, was studied. Contributory factors, such as length of time in transit or in storage, warm temperatures, the presence of air and moisture, particle size and form of sulfur, and the presence of sources of carbon, nitrogen and phosphorus nutrients, were reviewed. Laboratory experiments with adding sodium lauryl sulfate (SLS), a known biocide, to sulfur inoculated with Thiobacillus, proved to be an efficient method for controlling acidity development. At the concentration required for effectiveness SLS did not interfere with purity specifications, had negligible effect on moisture, and appeared to be compatible with current dust suppression application practices. 2 tabs., 3 figs.

  2. Energy and Biocides Storage Compounds: Synthesis and Characterization of Energetic Bridged Bis(triiodoazoles).

    Science.gov (United States)

    He, Chunlin; Zhao, Gang; Hooper, Joseph P; Shreeve, Jean'ne M

    2017-11-06

    Energetic bridged triiodopyrazoles and triiodoimidazoles were designed and synthsized by reacting potassium triiodopyrazolate or triiodoimidazolate with corresponding dichloro compounds. All compounds were fully characterized by 1 H and 13 C NMR spectroscopy, IR spectroscopy, and elemental analyses. The structure of compound 1 was further confirmed by single-crystal X-ray diffraction. All of the compounds exhibit good thermal stability with decomposition temperatures between 199 and 270 °C and high densities ranging from 2.804 to 3.358 g/cm 3 . The detonation performances and the detonation products were calculated by CHEETAH 7. Compound 3 (D v = 4765 m s -1 ; P = 17.9 GPa) and compound 7 (D v = 4841 m s -1 ; P = 18.5 GPa) show comparable detonation pressure to TNT, and high iodine content makes them promising as energy and biocides storage compounds.

  3. Acanthamoeba encystment: multifactorial effects of buffers, biocides, and demulcents present in contact lens care solutions

    Directory of Open Access Journals (Sweden)

    Kovacs CJ

    2015-10-01

    Full Text Available Christopher J Kovacs, Shawn C Lynch, Marjorie J Rah, Kimberly A Millard, Timothy W Morris Bausch & Lomb Incorporated, Rochester, NY, USA Purpose: To determine whether agents which are purportedly capable of inducing encystment of Acanthamoeba can recapitulate the signal when tested in differing formulations. Methods: In accordance with the International Standard ISO 19045, Acanthamoeba castellanii ATCC 50370 trophozoites were cultured in antibiotic-free axenic medium, treated with test solutions, and encystment rates plus viability were measured via bright field and fluorescent microscopy. Test solutions included phosphate-buffered saline (PBS, borate-buffered saline, biguanide- and hydrogen peroxide (H2O2-based biocides, propylene glycol (PG and povidone (POV ophthalmic demulcents, and one-step H2O2-based contact lens disinfection systems. Results: Only PBS solutions with 0.25 ppm polyaminopropyl biguanide (PAPB and increasing concentrations of PG and POV stimulated A. castellanii encystment in a dose-dependent manner, whereas PBS solutions containing 3% H2O2 and increasing concentrations of PG and POV did not stimulate encystment. Borate-buffered saline and PBS/citrate solutions containing PG also did not stimulate encystment. In addition, no encystment was observed after 24 hours, 7 days, or 14 days of exposures of trophozoites to one-step H2O2 contact lens disinfection products or related solutions. Conclusion: The lack of any encystment observed when trophozoites were treated with existing or new one-step H2O2 contact lens care products, as well as when trophozoites were exposed to various related test solutions, confirms that Acanthamoeba encystment is a complex process which depends upon simultaneous contributions of multiple factors including buffers, biocides, and demulcents. Keywords: propylene glycol, contact lens care system, hydrogen peroxide disinfecting solution

  4. Poly(lactic acid)/TiO{sub 2} nanocomposites as alternative biocidal and antifungal materials

    Energy Technology Data Exchange (ETDEWEB)

    Fonseca, Carmen; Ochoa, Almudena [POLCA, Departamento de Ingeniería Mecánica, Química y Diseño Industrial, Escuela Técnica Superior de Ingeniería y Diseño Industrial, Universidad Politécnica de Madrid, Ronda de Valencia 3, Madrid (Spain); Ulloa, Maria Teresa; Alvarez, Eduardo [Programa de Microbiología y Micología. ICBM-Facultad de Medicina Universidad de Chile, Dirección, Avenida Independencia 1027, Comuna Independencia, Santiago (Chile); Canales, Daniel [Grupo Polímeros, Facultad de Química y Biología, Universidad de Santiago de Chile, USACH, Casilla 40, Correo 33, Santiago (Chile); Zapata, Paula A., E-mail: paula.zapata@usach.cl [Grupo Polímeros, Facultad de Química y Biología, Universidad de Santiago de Chile, USACH, Casilla 40, Correo 33, Santiago (Chile)

    2015-12-01

    Poly(lactic acid) (PLA) composites with titanium oxide (TiO{sub 2}) ~ 10-nm nanoparticles were produced by the melting process and their main properties were evaluated. The nanoparticles are homogeneously dispersed in the matrix with a low degree of agglomeration, as seen by transmission electron microscopy (TEM). The crystallinity temperature increased ~ 12% when 5 wt.% of TiO{sub 2} was added, showing that the nanoparticles acted as nucleating agents this trend was confirmed by optical images. The elastic modulus increased ~ 54% compared to neat PLA at 5 wt.% of nanoparticles. Despite these improvements, PLA/TiO{sub 2} nanocomposites showed lower shear viscosity than neat PLA, possibly reflecting degradation of the polymer due to the particles. Regarding biocidal properties, after 2 h of contact the PLA/TiO{sub 2} composites with 8 wt.% TiO{sub 2} showed a reduction of Escherichia coli colonies of ~ 82% under no UVA irradiation compared to pure PLA. This biocidal characteristic can be increased under UVA irradiation, with nanocomposites containing 8 wt.% TiO{sub 2} killing 94% of the bacteria. The PLA/TiO{sub 2} nanocomposites with 8 wt.% were also 99.99% effective against Aspergillus fumigatus under the UVA irradiation. - Highlights: • PLA composites with titanium oxide (10 nm) were produced by the melting process. • The crystallinity temperature increased ~ 12% when 5 wt.% of TiO{sub 2} was added. • The elastic modulus increased ~ 54% compared to neat PLA. • The PLA/TiO{sub 2} composites showed a reduction of Escherichia coli colonies of 94%. • The PLA/TiO{sub 2} nanocomposites with 8 wt.% were also 99.99% effective against fungi.

  5. Toxic indole alkaloids avrainvillamide and stephacidin B produced by a biocide tolerant indoor mold Aspergillus westerdijkiae.

    Science.gov (United States)

    Mikkola, Raimo; Andersson, Maria A; Hautaniemi, Maria; Salkinoja-Salonen, Mirja S

    2015-06-01

    Toxic Aspergillus westerdijkiae were present in house dust and indoor air fall-out from a residence and a kindergarten where the occupants suffered from building related ill health. The A. westerdijkiae isolates produced indole alkaloids avrainvillamide (445 Da) and its dimer stephacidin B (890 Da). It grew and sporulated in presence of high concentrations of boron or polyguanidine (PHMB, PHMG) based antimicrobial biocides used to remediate mold infested buildings. The boar sperm cells were used as sensor cells to purify toxins from HPLC fractions of the fungal biomass. Submicromolar concentrations (EC50 0.3-0.4 μM) blocked boar spermatozoan motility and killed porcine kidney tubular epithelial cells (PK-15). Plate grown hyphal mass of the A. westerdijkiae isolates contained 300-750 ng of avrainvillamide and 30-300 ng of stephacidin B per mg (wet weight). The toxins induced rapid (30 min) loss of boar sperm motility, followed (24 h) by loss of mitochondrial membrane potential (ΔΨm). Apoptotic cell death was observed in PK-15 cell monolayers, prior to cessation of glucose uptake or loss of ΔΨm. Avrainvillamide and stephacidin B were 100-fold more potent towards the porcine cells than the mycotoxins stephacidin A, ochratoxin A, sterigmatocystin and citrinin. The high toxicity of stephacidin B indicates a role of nitrone group in the mechanism of toxicity. Avrainvillamide and stephacidin B represent a new class of toxins with possible a threat to human health in buildings. Furthermore, the use of biocides highly enhanced the growth of toxigenic A. westerdijkiae. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. From TBT to booster biocides: Levels and impacts of antifouling along coastal areas of Panama.

    Science.gov (United States)

    Batista-Andrade, Jahir Antonio; Caldas, Sergiane Souza; Batista, Rodrigo Moço; Castro, Italo Braga; Fillmann, Gilberto; Primel, Ednei Gilberto

    2018-03-01

    Antifouling biocides in surface sediments and gastropod tissues were assessed for the first time along coastal areas of Panama under the influence of maritime activities, including one of the world's busiest shipping zones: the Panama Canal. Imposex incidence was also evaluated in five muricid species distributed along six coastal areas of Panama. This TBT-related biological alteration was detected in three species, including the first report in Purpura panama. Levels of organotins (TBT, DBT, and MBT) in gastropod tissues and surficial sediments ranged from TBT inputs were observed in areas considered as moderate to highly contaminated mainly by inputs from fishing and leisure boats. Regarding booster biocides, TCMTB and dichlofluanid were not detected in any sample, while irgarol 1051, diuron and DCOIT levels ranged from TBT (149 ng Sn g -1 ) and irgarol 1051 (2.8 ng g -1 ), as well as relevant level of DCOIT (5.7 ng g -1 ), were detected in a marina used by recreational boats. Additionally, relatively high diuron values (14.1 ng g -1 ) were also detected in the Panama Canal associate to a commercial port. DCOIT concentrations were associated with the presence of antifouling paint particles in sediments obtained nearby shipyard or boat maintenance sites. The highest levels of TBT, irgarol 1051, and diuron exceeded international sediment quality guidelines indicating that toxic effects could be expected in coastal areas of Panama. Thus, the simultaneous impacts produced by new and old generations of antifouling paints highlight a serious environmental issue in Panamanian coastal areas. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. SeaNine 211 as antifouling biocide: A coastal pollutant of emerging concern.

    Science.gov (United States)

    Chen, Lianguo; Lam, James C W

    2017-11-01

    SeaNine 211, with 4,5-dichloro-2-n-octyl-4-isothiazolin-3-one (DCOIT) being the biocidal ingredient, is a widely-used antifouling agent to deter the undesirable biofouling phenomenon. It is commercially promoted as an environmentally acceptable antifoulant mainly due to its claimed rapid degradation in marine environment. However, increasing researches document varying degradative kinetics in different environments, proving that SeaNine 211 is actually not degraded equally fast around the world (half-life between antifouling coatings has also caused global contamination of marine environment in various compartments. For example, accumulation of SeaNine 211 is detected as high as 3700ng/L in Spanish seawater and 281ng/g dry weight in Korean sediment. Considering that SeaNine 211 is highly toxic against non-target marine organisms, environmental risk assessment finds that most marine organisms are endangered by SeaNine 211 in worst-case scenario. Its endocrine disrupting and reproductive impairing effects at environmentally worst-case concentrations further constitute a long-term threat to the maintenance of population stability. Therefore, in the light of the varying degradability, environmental pollution and high toxicity, especially the endocrine disruption, SeaNine 211 as an antifouling agent is likely to cause non-negligible damages to the marine ecosystem. There is an urgency to perform a systematic ecological risk assessment of SeaNine 211 to prevent the potential impacts on the health of marine environment. A regular monitoring also becomes necessary to place the usage of antifouling biocides under control. Copyright © 2017. Published by Elsevier B.V.

  8. Designing N-halamine based antibacterial surface on polymers: Fabrication, characterization, and biocidal functions

    Energy Technology Data Exchange (ETDEWEB)

    Chen Yong, E-mail: ychen168@126.com [Department of Applied Chemistry, College of Chemical and Environmental Engineering, Shandong University of Science and Technology, 579 Qianwangang Rd., Huangdao Zone, Qingdao 266510 (China); Han Qiuxia [Department of Biological Engineering, College of Chemical and Environmental Engineering, Shandong University of Science and Technology, Qingdao 266510 (China)

    2011-05-01

    We demonstrate a valuable method to generate reactive groups on inert polymer surfaces and bond antibacterial agents for biocidal ability. Polystyrene (PS) surfaces were functionalized by spin coating of sub-monolayer and monolayer films of poly(styrene-b-tert-butyl acrylate) (PS-PtBA) block copolymer from solutions in toluene. PS-PtBA self-assembled to a bilayer structure on PS that contains a surface layer of the PtBA blocks ordering at the air-polymer interface and a bottom layer of the PS blocks entangling with the PS substrate. The thickness of PtBA layer could be linearly controlled by the concentration of the spin coating solution and a 2.5 nm saturated monolayer coverage of PtBA was achieved at 0.35% (w/w). Carboxyl groups were generated by exposing the tert-butyl ester groups of PtBA on saturated surface to trifluoroacetic acid (TFA) to bond tert-butylamine via amide bonds that were further chlorinated to N-halamine with NaOCl solution. The density of N-halamine on the chlorinated surface was calculated to be 1.05 x 10{sup -5} mol/m{sup 2} by iodimetric/thiosulfate titration. Presented data showed the N-halamine surface provided powerful antibacterial activities against Staphylococcus aureus and Escherichia coli. Over 50% of the chlorine lost after UVA irradiation could be regained upon rechlorination. This design concept can be virtually applied to any inert polymer by choosing appropriate block copolymers and antibacterial agents to attain desirable biocidal activity.

  9. Occurrence and overlooked sources of the biocide carbendazim in wastewater and surface water.

    Science.gov (United States)

    Merel, Sylvain; Benzing, Saskia; Gleiser, Carolin; Di Napoli-Davis, Gina; Zwiener, Christian

    2018-08-01

    Carbendazim is a fungicide commonly used as active substance in plant protection products and biocidal products, for instance to protect facades of buildings against fungi. However, the subsequent occurrence of this fungicide and potential endocrine disruptor in the aqueous environment is a major concern. In this study, high resolution mass spectrometry shows that carbendazim can be detected with an increasing abundance from the source to the mouth of the River Rhine. Unexpectedly, the abundance of carbendazim correlates poorly with that of other fungicides used as active ingredients in plant protection products (r 2 of 0.32 for cyproconazole and r 2 of 0.57 for propiconazole) but it correlates linearly with that of pharmaceuticals (r 2 of 0.86 for carbamazepine and r 2 of 0.89 for lamotrigine). These results suggest that the occurrence of carbendazim in surface water comes mainly from the discharge of treated domestic wastewater. This hypothesis is further confirmed by the detection of carbendazim in wastewater effluents (n = 22). In fact, bench-scale leaching tests of textiles and papers revealed that these materials commonly found in households could be a source of carbendazim in domestic wastewater. Moreover, additional river samples collected nearby two paper industries indicate that the discharge of their treated process effluents is also a source of carbendazim in the environment. While characterizing paper and textile as overlooked sources of carbendazim, this study also shows the biocide as a possible ubiquitous wastewater contaminant that would require further systematic and worldwide monitoring due to its toxicological properties. Copyright © 2018 Elsevier Ltd. All rights reserved.

  10. Poly(lactic acid)/TiO2 nanocomposites as alternative biocidal and antifungal materials

    International Nuclear Information System (INIS)

    Fonseca, Carmen; Ochoa, Almudena; Ulloa, Maria Teresa; Alvarez, Eduardo; Canales, Daniel; Zapata, Paula A.

    2015-01-01

    Poly(lactic acid) (PLA) composites with titanium oxide (TiO 2 ) ~ 10-nm nanoparticles were produced by the melting process and their main properties were evaluated. The nanoparticles are homogeneously dispersed in the matrix with a low degree of agglomeration, as seen by transmission electron microscopy (TEM). The crystallinity temperature increased ~ 12% when 5 wt.% of TiO 2 was added, showing that the nanoparticles acted as nucleating agents this trend was confirmed by optical images. The elastic modulus increased ~ 54% compared to neat PLA at 5 wt.% of nanoparticles. Despite these improvements, PLA/TiO 2 nanocomposites showed lower shear viscosity than neat PLA, possibly reflecting degradation of the polymer due to the particles. Regarding biocidal properties, after 2 h of contact the PLA/TiO 2 composites with 8 wt.% TiO 2 showed a reduction of Escherichia coli colonies of ~ 82% under no UVA irradiation compared to pure PLA. This biocidal characteristic can be increased under UVA irradiation, with nanocomposites containing 8 wt.% TiO 2 killing 94% of the bacteria. The PLA/TiO 2 nanocomposites with 8 wt.% were also 99.99% effective against Aspergillus fumigatus under the UVA irradiation. - Highlights: • PLA composites with titanium oxide (10 nm) were produced by the melting process. • The crystallinity temperature increased ~ 12% when 5 wt.% of TiO 2 was added. • The elastic modulus increased ~ 54% compared to neat PLA. • The PLA/TiO 2 composites showed a reduction of Escherichia coli colonies of 94%. • The PLA/TiO 2 nanocomposites with 8 wt.% were also 99.99% effective against fungi

  11. Concentration patterns of agricultural pesticides and urban biocides in surface waters of a catchment of mixed land use

    Science.gov (United States)

    Stamm, C.; Wittmer, I.; Bader, H.-P.; Scheidegger, R.; Alder, A.; Lück, A.; Hanke, I.; Singer, H.

    2009-04-01

    Organic pesticides and biocides that are found in surface waters, can originate from agricultural and urban sources. For a long time, agricultural pesticides have received substantially more attention than biocidal compounds from urban use like material protection or in-can preservatives (cosmetics etc.). Recent studies however revealed that the amounts of urban biocides used may exceed those of agricultural pesticides. This study aims at comparing the input of several important pesticides and biocides into a small Swiss stream with a special focus on loss events triggered by rainfall. A set of 16 substances was selected to represent urban and agricultural sources. The selected substances are either only used as biocides (irgarol, isothiazolinones, IPBC), as pesticides (atrazine, sulcotrione, dichlofluanid, tolylfluanid) or have a mixed use (isoproturon, terbutryn, terbutylazine, mecoprop, diazinon, carbendazim) The study catchment has an area of 25 km2 and is inhabited by about 12'000 people. Four sampling sites were selected in the river system in order to reflect different urban and agricultural sources. Additionally, we sampled a combined sewer overflow, a rain sewer and the outflow of a wastewater treatment plant. At each site discharge was measured continuously from March to November 2007. During 16 rain events samples were taken by automatic devices at a high temporal resolution. The results, based on more than 500 analyzed samples, revealed distinct concentration patterns for different compounds and sources. Agricultural pesticides exhibited a strong seasonality as expected based on the application periods. During the first one or two rain events after application the concentrations reached up to several thousand ng/l during peak flow (atrazine, isoproturon). The temporal patterns of urban biocides were more diverse. Some compounds obviously stem from permanent sources independent of rainfall because they were found mostly in the outlet of the wastewater

  12. Combined treatments of enterocin AS-48 with biocides to improve the inactivation of methicillin-sensitive and methicillin-resistant Staphylococcus aureus planktonic and sessile cells.

    Science.gov (United States)

    Caballero Gómez, Natacha; Abriouel, Hikmate; Grande, M José; Pérez Pulido, Rubén; Gálvez, Antonio

    2013-05-15

    Control of staphylococci during cleaning and disinfection is important to the food industry. Broad-spectrum bacteriocins with proved anti-staphylococcal activity, such as enterocin AS-48, could open new possibilities for disinfection in combination with biocides. In the present study, enterocin AS-48 was tested singly or in combination with biocides against a cocktail of six Staphylococcus aureus strains (including three methicillin-resistant strains) in planktonic state as well as in biofilms formed on polystyrene microtiter plates. Cells were challenged with enterocin, biocides or enterocin/biocide combinations. Inactivation of planktonic cells increased significantly (penterocin AS-48 (25mg/l) was tested in combination with benzalkonium chloride (BC), cetrimide (CT) and hexadecylpyridinium chloride (HDP), and non-significantly in combination with didecyldimethylammonium bromide (AB), triclosan (TC), hexachlorophene (CF), polyhexamethylen guanidinium chloride (PHMG), chlorhexidine (CH) or P3-oxonia (OX). In the sessile state (24h biofilms), staphylococci required higher biocide concentrations in most cases, except for OX. Inactivation of sessile staphylococci increased remarkably when biocides were applied in combination with enterocin AS-48, especially when the bacteriocin was added at 50mg/l. During storage, the concentrations of sessile as well as planktonic cells in the treated samples decreased remarkably for BC, TC and PHMG, but OX failed to inhibit proliferation of the treated biofilms as well as growth of planktonic cells. The observed inhibitory effects during storage were potentiated when the biocides were combined with 50 mg/l enterocin AS-48. Results from this study suggest that selected combinations of enterocin AS-48 and biocides offer potential use against planktonic and sessile, methicillin-sensitive and methicillin-resistant S. aureus. Copyright © 2013 Elsevier B.V. All rights reserved.

  13. Biocidas. Eficacia. Criterios para su evaluación y autorización Biocides. Efficacy. Criteria for its assessment and authorization

    Directory of Open Access Journals (Sweden)

    Covadonga Caballo Diéguez

    2006-12-01

    .Article 13 of Royal Decree 865/2003, 4 July, establishes hygienic-sanitary criteria for prevention and control of Legionellosis, provides for the use of disinfectants duly authorized by Public Health General Directorate, in the course of hygienic-sanitary maintenance operations.In accordance with existing national laws among requirements necessary to effect said authorization are the due efficacy assay product, physic-chemical properties, data on toxicity and ecotoxicity and information on incompatibility with other chemicals used in installations, as well as materials constitutive of the latter.Public Health General Directorate, General Subdirectorate of Environmental Health and Labour Health, studies and assesses the information provided by the applicant if appropriate the product is included in the Public Health General Directorate Official Register.Up until 1st June 2006, 183 disinfectants products against Legionella are registered in the Public Health General Directorate. The said disinfectant products may be classified according to their action substances, and the way in which they act, into oxidants and non-oxidants all of them interacting the different with factors linked to Legionella proliferation. Nonetheless, efficacy of oxidant and non-oxidant biocides will depend on conditions such as: specific characteristics of the installation itself (dimensions, material, technology, usage and maintenance frequency, location, use of products that might interfere with the used biocide.Although efficacy assays conducted to register these biocides rest mostly on laboratory studies, their “in vivo” efficacy should not be questioned without considering the above listed factors.

  14. Evaluation of epidemiological cut-off values indicates that biocide resistant subpopulations are uncommon in natural isolates of clinically-relevant microorganisms.

    Directory of Open Access Journals (Sweden)

    Ian Morrissey

    Full Text Available To date there are no clear criteria to determine whether a microbe is susceptible to biocides or not. As a starting point for distinguishing between wild-type and resistant organisms, we set out to determine the minimal inhibitory concentration (MIC and minimal bactericidal concentration (MBC distributions for four common biocides; triclosan, benzalkonium chloride, chlorhexidine and sodium hypochlorite for 3319 clinical isolates, with a particular focus on Staphylococcus aureus (N = 1635 and Salmonella spp. (N = 901 but also including Escherichia coli (N = 368, Candida albicans (N = 200, Klebsiella pneumoniae (N = 60, Enterobacter spp. (N = 54, Enterococcus faecium (N = 53, and Enterococcus faecalis (N = 56. From these data epidemiological cut-off values (ECOFFs are proposed. As would be expected, MBCs were higher than MICs for all biocides. In most cases both values followed a normal distribution. Bimodal distributions, indicating the existence of biocide resistant subpopulations were observed for Enterobacter chlorhexidine susceptibility (both MICs and MBCs and the susceptibility to triclosan of Enterobacter (MBC, E. coli (MBC and MIC and S. aureus (MBC and MIC. There is a concern on the potential selection of antibiotic resistance by biocides. Our results indicate however that resistance to biocides and, hence any potential association with antibiotic resistance, is uncommon in natural populations of clinically relevant microorganisms.

  15. Combined biocidal action of silver nanoparticles and ions against Chlorococcales (Scenedesmus quadricauda, Chlorella vulgaris) and filamentous algae (Klebsormidium sp.).

    Czech Academy of Sciences Publication Activity Database

    Žouželka, Radek; Čiháková, P.; Říhová Ambrožová, J.; Rathouský, Jiří

    2016-01-01

    Roč. 23, č. 19 (2016), s. 8317-8326 ISSN 0944-1344 R&D Projects: GA MK(CZ) DF11P01OVV012 Keywords : silver nanoparticles * silver ions * concentration of silver ions in equilibrium with silver nanoparticles Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 2.741, year: 2016

  16. In-situ Growth of Biocidal AgCl Crystals in the Top Layer of Asymmetric Polytriazole Membranes

    KAUST Repository

    Villalobos, Luis Francisco; Chisca, Stefan; Cheng, Hong; Hong, Pei-Ying; Nunes, Suzana Pereira; Peinemann, Klaus-Viktor

    2016-01-01

    Scalable fabrication strategies to concentrate biocidal materials in only the surface of membranes are highly desirable. In this letter, tight-UF polytriazole membranes with a high concentration of biocide silver chloride (AgCl) crystals dispersed in only their top layer are presented. They were made following a simple dual-bath process that is compatible with current commercial membrane casting facilities. These membranes can achieve a 150-fold increase in their antimicrobial character compared to their silver-free counterpart. Moreover, fine-tuning of their properties is straightforward. A change in the silver concentration in one of the baths is enough to tune the permeance, molecular weight cut-off (MWCO) and silver loading of the final membrane.

  17. The corrosion behaviour of galvanized steel in cooling tower water containing a biocide and a corrosion inhibitor.

    Science.gov (United States)

    Minnoş, Bihter; Ilhan-Sungur, Esra; Çotuk, Ayşın; Güngör, Nihal Doğruöz; Cansever, Nurhan

    2013-01-01

    The corrosion behaviour of galvanized steel in cooling tower water containing a biocide and a corrosion inhibitor was investigated over a 10-month period in a hotel. Planktonic and sessile numbers of sulphate reducing bacteria (SRB) and heterotrophic bacteria were monitored. The corrosion rate was determined by the weight loss method. The corrosion products were analyzed by energy dispersive X-ray spectroscopy and X-ray diffraction. A mineralized, heterogeneous biofilm was observed on the coupons. Although a biocide and a corrosion inhibitor were regularly added to the cooling water, the results showed that microorganisms, such as SRB in the mixed species biofilm, caused corrosion of galvanized steel. It was observed that Zn layers on the test coupons were completely depleted after 3 months. The Fe concentrations in the biofilm showed significant correlations with the weight loss and carbohydrate concentration (respectively, p < 0.01 and p < 0.01).

  18. In-situ Growth of Biocidal AgCl Crystals in the Top Layer of Asymmetric Polytriazole Membranes

    KAUST Repository

    Villalobos, Luis Francisco

    2016-05-06

    Scalable fabrication strategies to concentrate biocidal materials in only the surface of membranes are highly desirable. In this letter, tight-UF polytriazole membranes with a high concentration of biocide silver chloride (AgCl) crystals dispersed in only their top layer are presented. They were made following a simple dual-bath process that is compatible with current commercial membrane casting facilities. These membranes can achieve a 150-fold increase in their antimicrobial character compared to their silver-free counterpart. Moreover, fine-tuning of their properties is straightforward. A change in the silver concentration in one of the baths is enough to tune the permeance, molecular weight cut-off (MWCO) and silver loading of the final membrane.

  19. Quorum Sensing and the Use of Quorum Quenchers as Natural Biocides to Inhibit Sulfate-Reducing Bacteria

    Directory of Open Access Journals (Sweden)

    Giantommaso Scarascia

    2016-12-01

    Full Text Available Sulfate-reducing bacteria (SRB are one of the main protagonist groups of biocorrosion in the seawater environment. Given their principal role in biocorrosion, it remains a crucial task to develop strategies to reduce the abundance of SRBs. Conventional approaches include the use of biocides and antibiotics, which can impose health, safety, and environmental concerns. This review examines an alternative approach to this problem. This is achieved by reviewing the role of quorum sensing (QS in SRB populations and its impact on the biofilm formation process. Genome databases of SRBs are mined to look for putative QS systems and homologous protein sequences representative of autoinducer receptors or synthases. Subsequently, this review puts forward the potential use of quorum quenchers as natural biocides against SRBs and outlines the potential strategies for the implementation of this approach.

  20. Quorum Sensing and the Use of Quorum Quenchers as Natural Biocides to Inhibit Sulfate-Reducing Bacteria

    KAUST Repository

    Scarascia, Giantommaso; Wang, Tiannyu; Hong, Pei-Ying

    2016-01-01

    Sulfate-reducing bacteria (SRB) are one of the main protagonist groups of biocorrosion in the seawater environment. Given their principal role in biocorrosion, it remains a crucial task to develop strategies to reduce the abundance of SRBs. Conventional approaches include the use of biocides and antibiotics, which can impose health, safety, and environmental concerns. This review examines an alternative approach to this problem. This is achieved by reviewing the role of quorum sensing (QS) in SRB populations and its impact on the biofilm formation process. Genome databases of SRBs are mined to look for putative QS systems and homologous protein sequences representative of autoinducer receptors or synthases. Subsequently, this review puts forward the potential use of quorum quenchers as natural biocides against SRBs and outlines the potential strategies for the implementation of this approach.

  1. Quorum Sensing and the Use of Quorum Quenchers as Natural Biocides to Inhibit Sulfate-Reducing Bacteria

    KAUST Repository

    Scarascia, Giantommaso

    2016-12-15

    Sulfate-reducing bacteria (SRB) are one of the main protagonist groups of biocorrosion in the seawater environment. Given their principal role in biocorrosion, it remains a crucial task to develop strategies to reduce the abundance of SRBs. Conventional approaches include the use of biocides and antibiotics, which can impose health, safety, and environmental concerns. This review examines an alternative approach to this problem. This is achieved by reviewing the role of quorum sensing (QS) in SRB populations and its impact on the biofilm formation process. Genome databases of SRBs are mined to look for putative QS systems and homologous protein sequences representative of autoinducer receptors or synthases. Subsequently, this review puts forward the potential use of quorum quenchers as natural biocides against SRBs and outlines the potential strategies for the implementation of this approach.

  2. Predictive Studies Suggest that the Risk for the Selection of Antibiotic Resistance by Biocides Is Likely Low in Stenotrophomonas maltophilia.

    Directory of Open Access Journals (Sweden)

    María Blanca Sánchez

    Full Text Available Biocides are used without restriction for several purposes. As a consequence, large amounts of biocides are released without any control in the environment, a situation that can challenge the microbial population dynamics, including selection of antibiotic resistant bacteria. Previous work has shown that triclosan selects Stenotrophomonas maltophilia antibiotic resistant mutants overexpressing the efflux pump SmeDEF and induces expression of this pump triggering transient low-level resistance. In the present work we analyze if two other common biocides, benzalkonium chloride and hexachlorophene, trigger antibiotic resistance in S. maltophilia. Bioinformatic and biochemical methods showed that benzalkonium chloride and hexachlorophene bind the repressor of smeDEF, SmeT. Only benzalkonium chloride triggers expression of smeD and its effect in transient antibiotic resistance is minor. None of the hexachlorophene-selected mutants was antibiotic resistant. Two benzalkonium chloride resistant mutants presented reduced susceptibility to antibiotics and were impaired in growth. Metabolic profiling showed they were more proficient than their parental strain in the use of some dipeptides. We can then conclude that although bioinformatic predictions and biochemical studies suggest that both hexachlorophene and benzalkonium chloride should induce smeDEF expression leading to transient S. maltophilia resistance to antibiotics, phenotypic assays showed this not to be true. The facts that hexachlorophene resistant mutants are not antibiotic resistant and that the benzalkonium chloride resistant mutants presenting altered susceptibility to antibiotics were impaired in growth suggests that the risk for the selection (and fixation of S. maltophilia antibiotic resistant mutants by these biocides is likely low, at least in the absence of constant selection pressure.

  3. Prevalence of bacteria resistant to antibiotics and/or biocides on meat processing plant surfaces throughout meat chain production.

    Science.gov (United States)

    Lavilla Lerma, Leyre; Benomar, Nabil; Gálvez, Antonio; Abriouel, Hikmate

    2013-02-01

    In order to investigate the prevalence of resistant bacteria to biocides and/or antibiotics throughout meat chain production from sacrifice till end of production line, samples from various surfaces of a goat and lamb slaughterhouse representative of the region were analyzed by the culture dependent approach. Resistant Psychrotrophs (n=255 strains), Pseudomonas sp. (n=166 strains), E. coli (n=23 strains), Staphylococcus sp. (n=17 strains) and LAB (n=82 represented mainly by Lactobacillus sp.) were isolated. Resistant psychrotrophs and pseudomonads (47 and 29%, respectively) to different antimicrobials were frequently detected in almost all areas of meat processing plant regardless the antimicrobial used, although there was a clear shift in the spectrum of other bacterial groups and for this aim such resistance was determined according to several parameters: antimicrobial tested, sampling zone and the bacterial group. Correlation of different parameters was done using a statistical tool "Principal component analysis" (PCA) which determined that quaternary ammonium compounds and hexadecylpyridinium were the most relevant biocides for resistance in Pseudomonas sp., while ciprofloxacin and hexachlorophene were more relevant for psychrotrophs, LAB, and in lesser extent Staphylococcus sp. and Escherichia coli. On the other hand, PCA of sampling zones determined that sacrifice room (SR) and cutting room (CR) considered as main source of antibiotic and/or biocide resistant bacteria showed an opposite behaviour concerning relevance of antimicrobials to determine resistance being hexadecylpyridinium, cetrimide and chlorhexidine the most relevant in CR, while hexachlorophene, oxonia 6P and PHMG the most relevant in SR. In conclusion, rotational use of the relevant biocides as disinfectants in CR and SR is recommended in an environment which is frequently disinfected. Copyright © 2012 Elsevier B.V. All rights reserved.

  4. Biocide plants as a sustainable tool for the control of pests and pathogens in vegetable cropping systems

    OpenAIRE

    Trifone D'Addabbo; Sebastiano Laquale; Stella Lovelli; Vincenzo Candido; Pinarosa Avato

    2014-01-01

    Synthetic pesticides have played a major role in crop protection related to the intensification of agricultural systems. In the recent years, environmental side effects and health concerns raised by an indiscriminate use have led the EU to the ban of many synthetic pesticides. As a result of this drastic revision, currently there is a strong need for new and alternative pest control methods. An interesting source of biorational pesticides may be represented by the biocidal compounds naturally...

  5. Comparing a microbial biocide and chlorine as zebra mussel control strategies in an Irish drinking water treatment plant

    OpenAIRE

    Sara Meehan; Frances E. Lucy; Bridget Gruber; Sarahann Rackl

    2013-01-01

    A need exists for an environmentally friendly mussel control method to replace chlorine and other traditional control methods currentlyutilised in drinking water plants and other infested facilities. Zequanox® is a newly commercialised microbial biocide for zebra and quaggamussels comprised of killed Pseudomonas fluorescens CL145A cells. The objective of this study was to compare the efficacy of adevelopmental formulation of Zequanox (referred to as MBI 401 FDP) and chlorine treatments on adu...

  6. Co-Selection of Resistance to Antibiotics, Biocides and Heavy Metals, and Its Relevance to Foodborne Pathogens

    OpenAIRE

    Wales, Andrew; Davies, RH

    2015-01-01

    Concerns have been raised in recent years regarding co-selection for antibiotic resistance among bacteria exposed to biocides used as disinfectants, antiseptics and preservatives, and to heavy metals (particularly copper and zinc) used as growth promoters and therapeutic agents for some livestock species. There is indeed experimental and observational evidence that exposure to these non-antibiotic antimicrobial agents can induce or select for bacterial adaptations that result in decreased sus...

  7. Bio-testing integral toxicity of corrosion inhibitors, biocides and oil hydrocarbons in oil-and gas-processing industry

    Energy Technology Data Exchange (ETDEWEB)

    Chugunov, V.A.; Kholodenko, V.P.; Irkhina, I.A.; Fomchenkov, V.M.; Novikov, I.A. [State Research Center for Applied Microbiology, Obolensk, Moscow (Russian Federation)

    2004-07-01

    In recent years bioassays have been widely used for assessing levels of contamination of the environment. This is due to the fact that test-organisms provide a general response to toxicants present in samples. Based on microorganisms as test objects, it is possible to develop cheap, sensitive and rapid assays to identify environmental xenobiotics and toxicants. The objective of the research was to develop different microbiological assays for assessing integral toxicity of water environments polluted with corrosion inhibitors, biocides and hydrocarbons in oil- and gas-processing industry. Bio-luminescent, electro-orientational, osmo-optic and microorganism reducing activity assays were used for express evaluation of integral toxicity. They are found to determine promptly integral toxicity of water environments containing various pollutants (oil, oil products, corrosion inhibitors, biocides). Results conclude that the assays may be used for analyzing integral toxicity of water polluted with hydrocarbons, as well as for monitoring of water changes as a result of biodegradation of pollutants by microorganisms and their associations. Using a kit of different assays, it is also possible to evaluate ecological safety of biocides, corrosion inhibitors, and their compositions. Bioassays used as a kit are more effective than each assay individually, allowing one to get complete characterization of a reaction of bacterial test organisms to different environments. (authors)

  8. Basic substances under EC 1107/2009 phytochemical regulation: experience with non-biocide and food products as biorationals

    Directory of Open Access Journals (Sweden)

    Marchand Patrice A.

    2016-07-01

    Full Text Available Basic Substances are a newly effective category of Plant Protection Product under EC Regulation No 1107/2009. The first approved application of Equisetum arvense L. opened Part C of Implementing Regulation (EU No 540/2011, which lists the basic substance approved. Although E. arvense was described as a fungicide extract, subsequent applications like chitosan were related to non-biocide molecules. Consequently, plant protection product data were collected from research on alternative or traditional crop protection methods. They are notably issued or derived from foodstuffs (plants, plant by-products, plant derived products, substances and derived substances from animal origin. Applications are currently submitted by our Institute, under evaluation at different stages of the approval process or already approved. Remarkably, this Basic Substance category under pesticide EU Regulation was surprisingly designed for these non-biocidal plant protection products. In fact, components described as the “active substance” of most of the actual applications are food products like sugars and lecithin. Basic Substance applications for these foodstuffs are therefore a straightforward way of easily gaining approval for them. Here we describe the approval context and detail the agricultural uses of theses food products as Biological Control Agents (BCAs or biorationals for crop protection. From all deposited or approved Basic Substance Application (BSA, a proof has been provided that non-biocide and food products via physical barrier or lure effects may be effective plant protection products with an acceptable low profile of concern for public and agricultural safety.

  9. Technical protocol for laboratory tests of transformation of veterinary medicinal products and biocides in liquid manures. Version 1.0

    Energy Technology Data Exchange (ETDEWEB)

    Kreuzig, Robert [Technische Univ. Braunschweig (Germany). Inst. fuer Oekologische Chemie und Abfallanalytik

    2010-07-15

    The technical protocol under consideration describes a laboratory test method to evaluate the transformation of chemicals in liquid bovine and pig manures under anaerobic conditions and primarily is designed for veterinary medicinal products and biocides. The environmentally relevant entry routes into liquid manures occur via urine and feces of cattle and pigs in stable housings after excretion of veterinary medicinal products as parent compounds or metabolites and after the application of biocides in animal housings. Further entry routes such as solid dung application and direct dung pat deposition by production animals on pasture are not considered by this technical protocol. Thus, this technical protocol focused on the sampling of excrements from cattles and pigs kept in stables and fed under standard nutrition conditions. This approach additionally ensures that excrement samples are operationally free of any contamination by veterinary medicinal products and biocides. After the matrix characterization, reference-manure samples are prepared from the excrement samples by adding tap water to adjust defined dry substance contents typical for bovine or pig manures. This technical protocol comprehends a tiered experimental design in two parts: (a) Sampling of excrements and preparation of reference bovine and pig manures; (b) Testing of anaerobic transformation of chemicals in reference manures.

  10. Insectes ravageurs et propriétés biocides de Jatropha curcas L. (Euphorbiaceae : synthèse bibliographique

    Directory of Open Access Journals (Sweden)

    Abdoul Habou, Z.

    2013-01-01

    Full Text Available Insect pests and biocidal properties of Jatropha curcas L. (Euphorbiaceae. A review. Jatropha curcas is a Euphorbiaceae shrub widely distributed in many tropical countries. Its seeds are rich in oil that can be used as biofuel in modified diesel engines. Several insect species, mainly belonging to Hemiptera, Coleoptera and Orthoptera, have been referenced as insect pests of J. curcas. These insects attack the plant and cause damage to fruits, inflorescences and leaves. The most frequently observed pests belong to the genus Pachycoris (Heteroptera: Scutelleridae, which are widely distributed in Mexico, Australia, United States of America, Brazil and Nicaragua. Pachycoris spp. cause significant damage to the fruits, leading to the malformation of seeds and a reduction in their oil content. Although Jatropha shrubs are subjected to insect infestations, the oil has been shown to demonstrate biocidal activity, including insecticidal effects against several insect pests, including Busseola fusca (Fuller (Lepidoptera: Noctuidae, Sesamia calamistis Hampson (Lepidoptera: Noctuidae, Aphis gossypii Glover (Homoptera: Aphididae and Callosobruchus chinensis L. (Coleoptera: Bruchidae. In the present paper, we summarize the work carried out on inventories of J. curcas insect pests as well as on the biocidal activity of its oil.

  11. The influence of water chemistry and biocide additions on the response of an on-line biofilm monitor

    International Nuclear Information System (INIS)

    Licina, G.J.; Nekoksa, G.

    1995-01-01

    Microbiologically influenced corrosion (MIC) is a significant cause of degradation of piping and heat transfer surfaces in cooling water systems. The interaction between the metabolic processes of microorganisms attached to metallic surfaces and corrosion processes can lead to localized corrosion and rapid penetration of piping and heat exchanger tubes. On-line Monitoring of biofilm formation on Metallic Surfaces is a key both for automatic control equipment and for system operators so that mitigation activities can be initiated well before the structural integrity of piping or components is jeopardized. In addition, tracking of biofilm activity on line provides feedback useful for evaluating the effectiveness of biocide additions and optimizing the concentrations and addition schedules of biocides and other control chemicals. A probe has been developed to provide a method for determining the onset of biofilm formation on metal surfaces and tracking biofilm activity on line in a power plant or industrial environment; in fresh water and seawater environments. Experience with the system in a variety of water chemistries, and system responses to biofilm growth and subsequent destruction by biocide additions are described

  12. Commercial Biocides Induce Transfer of Prophage Φ13 from Human Strains of Staphylococcus aureus to Livestock CC398

    Directory of Open Access Journals (Sweden)

    Yuanyue Tang

    2017-12-01

    Full Text Available Human strains of Staphylococcus aureus commonly carry the bacteriophage ΦSa3 that encodes immune evasion factors. Recently, this prophage has been found in livestock-associated, methicillin resistant S. aureus (MRSA CC398 strains where it may promote human colonization. Here, we have addressed if exposure to biocidal products induces phage transfer, and find that during co-culture, Φ13 from strain 8325, belonging to ΦSa3 group, is induced and transferred from a human strain to LA-MRSA CC398 when exposed to sub-lethal concentrations of commercial biocides containing hydrogen peroxide. Integration of ΦSa3 in LA-MRSA CC398 occurs at multiple positions and the integration site influences the stability of the prophage. We did not observe integration in hlb encoding β-hemolysin that contains the preferred ΦSa3 attachment site in human strains, and we demonstrate that this is due to allelic variation in CC398 strains that disrupts the phage attachment site, but not the expression of β-hemolysin. Our results show that hydrogen peroxide present in biocidal products stimulate transfer of ΦSa3 from human to LA-MRSA CC398 strains and that in these strains prophage stability depends on the integration site. Knowledge of ΦSa3 transfer and stability between human and livestock strains may lead to new intervention measures directed at reducing human infection by LA-MRSA strains.

  13. Commercial Biocides Induce Transfer of Prophage Φ13 from Human Strains of Staphylococcus aureus to Livestock CC398.

    Science.gov (United States)

    Tang, Yuanyue; Nielsen, Lene N; Hvitved, Annemette; Haaber, Jakob K; Wirtz, Christiane; Andersen, Paal S; Larsen, Jesper; Wolz, Christiane; Ingmer, Hanne

    2017-01-01

    Human strains of Staphylococcus aureus commonly carry the bacteriophage ΦSa3 that encodes immune evasion factors. Recently, this prophage has been found in livestock-associated, methicillin resistant S. aureus (MRSA) CC398 strains where it may promote human colonization. Here, we have addressed if exposure to biocidal products induces phage transfer, and find that during co-culture, Φ13 from strain 8325, belonging to ΦSa3 group, is induced and transferred from a human strain to LA-MRSA CC398 when exposed to sub-lethal concentrations of commercial biocides containing hydrogen peroxide. Integration of ΦSa3 in LA-MRSA CC398 occurs at multiple positions and the integration site influences the stability of the prophage. We did not observe integration in hlb encoding β-hemolysin that contains the preferred ΦSa3 attachment site in human strains, and we demonstrate that this is due to allelic variation in CC398 strains that disrupts the phage attachment site, but not the expression of β-hemolysin. Our results show that hydrogen peroxide present in biocidal products stimulate transfer of ΦSa3 from human to LA-MRSA CC398 strains and that in these strains prophage stability depends on the integration site. Knowledge of ΦSa3 transfer and stability between human and livestock strains may lead to new intervention measures directed at reducing human infection by LA-MRSA strains.

  14. Green and brown propolis: efficient natural biocides for the control of bacterial contamination of alcoholic fermentation of distilled beverage

    Directory of Open Access Journals (Sweden)

    Márcia Justino Rossini Mutton

    2014-12-01

    Full Text Available This study aimed to evaluate the efficiency of natural biocides, brown and green propolis, for the control of bacterial contamination in the production of sugarcane spirit. The treatments consisted of brown and green propolis extracts, ampicillin, and a control and were assessed at the beginning and end of harvest season in ten fermentation cycles. In the microbiological analyses, the lactic acid bacteria were quantified in the inoculum before and after the treatment with biocides, and the viability of yeast cells during fermentation was evaluated. The levels of acids, glycerol, total residual reducing sugars, and ethanol were analyzed for the wine resulting from each fermentation cycle. A reduction in the number of bacterial contaminants in the inoculum in the treatments with the natural biocides was observed, but it did not affect the viability of yeast cells. The control of the contaminants led to the production of higher levels of ethanol and reduced acidity in the wine produced. The results of the use of brown and green propolis to control the growth microorganisms in the fermentation of sugarcane spirit can be of great importance for using alternative strategies to synthetic antibacterials in fermentation processes including other distilled beverage or spirits.

  15. Remote population-based intervention for disruptive behavior at age four: study protocol for a randomized trial of Internet-assisted parent training (Strongest Families Finland-Canada)

    Science.gov (United States)

    2013-01-01

    Background Oppositional Defiant Disorder (ODD) is characterized by angry and noncompliant behaviour. It is the most common disruptive behaviour disorder (DBD), with prevalence estimates of 6-9% for preschoolers and is closely linked to several long-term difficulties, including disorders of conduct, mood, anxiety, impulse-control, and substance abuse. ODD in children is related to parental depression, family dysfunction, and impairments in parental work performance. Children displaying early DBDs exhibit more symptoms of greater severity, more frequent offences, and commit more serious crimes later in life. The goal of the Strongest Families™ Finland Canada (SFFC) Smart Website intervention research program is to develop and evaluate an affordable, accessible, effective secondary prevention parent training program for disruptive behaviour in preschoolers to prevent the negative sequelae of ODD. Strongest Families is an 11-session program with two booster sessions that focuses on teaching skills to: strengthen parent–child relationships; reinforce positive behaviour; reduce conflict; manage daily transitions; plan for potentially problematic situations; promote emotional regulation and pro-social behaviour and decrease antisocial behaviour. Methods/design This protocol paper describes an ongoing population-based randomized controlled trial (RCT) of high-risk 4 year-olds attending well-child clinics in Turku, Finland and environs to examine the effectiveness of the Strongest Families Smart Website intervention compared to an Education Control condition. Randomization consists of a 1:1 ratio for intervention versus the education group, stratified by the child’s sex. The participants randomized to the intervention group receive access to the Strongest Families Smart Website and weekly telephone coaching sessions. The participants randomized to the Education Control condition receive access to a static website with parenting tips. Children are followed using

  16. Remote population-based intervention for disruptive behavior at age four: study protocol for a randomized trial of Internet-assisted parent training (Strongest Families Finland-Canada).

    Science.gov (United States)

    McGrath, Patrick J; Sourander, Andre; Lingley-Pottie, Patricia; Ristkari, Terja; Cunningham, Charles; Huttunen, Jukka; Filbert, Katharine; Aromaa, Minna; Corkum, Penny; Hinkka-Yli-Salomäki, Susanna; Kinnunen, Malin; Lampi, Katja; Penttinen, Anne; Sinokki, Atte; Unruh, Anita; Vuorio, Jenni; Watters, Carolyn

    2013-10-21

    Oppositional Defiant Disorder (ODD) is characterized by angry and noncompliant behaviour. It is the most common disruptive behaviour disorder (DBD), with prevalence estimates of 6-9% for preschoolers and is closely linked to several long-term difficulties, including disorders of conduct, mood, anxiety, impulse-control, and substance abuse. ODD in children is related to parental depression, family dysfunction, and impairments in parental work performance. Children displaying early DBDs exhibit more symptoms of greater severity, more frequent offences, and commit more serious crimes later in life. The goal of the Strongest Families Finland Canada (SFFC) Smart Website intervention research program is to develop and evaluate an affordable, accessible, effective secondary prevention parent training program for disruptive behaviour in preschoolers to prevent the negative sequelae of ODD. Strongest Families is an 11-session program with two booster sessions that focuses on teaching skills to: strengthen parent-child relationships; reinforce positive behaviour; reduce conflict; manage daily transitions; plan for potentially problematic situations; promote emotional regulation and pro-social behaviour and decrease antisocial behaviour. This protocol paper describes an ongoing population-based randomized controlled trial (RCT) of high-risk 4 year-olds attending well-child clinics in Turku, Finland and environs to examine the effectiveness of the Strongest Families Smart Website intervention compared to an Education Control condition. Randomization consists of a 1:1 ratio for intervention versus the education group, stratified by the child's sex. The participants randomized to the intervention group receive access to the Strongest Families Smart Website and weekly telephone coaching sessions. The participants randomized to the Education Control condition receive access to a static website with parenting tips. Children are followed using parental and daycare teacher measures

  17. Antifouling biocides in German marinas: Exposure assessment and calculation of national consumption and emission.

    Science.gov (United States)

    Daehne, Dagmar; Fürle, Constanze; Thomsen, Anja; Watermann, Burkard; Feibicke, Michael

    2017-09-01

    The authorization of biocidal antifouling products for leisure boats is the subject of the European Union Biocides Regulation 528/2012. National specifics may be regarded by the member states in their assessment of environmental risks. The aim of this survey was to collect corresponding data and to create a database for the environmental risk assessment of antifouling active substances in German surface waters. Water concentrations of current antifouling active substances and selected breakdown products were measured in a single-sampling campaign covering 50 marinas at inland and coastal areas. Increased levels were found for Zn, Cu, and cybutryne. For the latter, the maximum allowable concentration according to Directive 2013/39/EU was exceeded at 5 marinas. For Cu, local environmental quality standards were exceeded at 10 marinas. Base data on the total boat inventory in Germany were lacking until now. For that reason, a nationwide survey of mooring berths was conducted by use of aerial photos. About 206 000 mooring berths obviously used by boats with a potential antifouling application were counted. The blind spot of very small marinas was estimated at 20 000 berths. Seventy-one percent of berths were located at freshwater sites, illustrating the importance of navigable inland waterways for leisure boat activities and underlining the need for a customized exposure assessment in these areas. Moreover, the national consumption of all antifouling products for leisure boats was calculated. The total amount of 794 tonnes/annum (t/a) consisted of 179 t/a of inorganic Cu compounds, 19 t/a of organic cobiocides, and 49.5 t/a of Zn. With regard to weight proportion, 141 t/a Cu and 40 t/a Zn were consumed. Assuming an emission ratio of 50% during service life, 70.5 t/a of Cu amounted to 15% of all external sources for Cu release to German surface waters. These figures highlight the need for mitigation measures. Integr Environ Assess Manag 2017;13:892-905. © 2017 The

  18. The wide spectrum high biocidal potency of Bioxy formulation when dissolved in water at different concentrations

    Science.gov (United States)

    Dagher, Fadi

    2017-01-01

    Traditional surface disinfectants that have long been applied in medicine, animal husbandry, manufacturing and institutions are inconvenient at best and dangerous at worst. Moreover, some of these substances have adverse environmental impacts: for example, quaternary ammonium compounds (“quats”) are reproductive toxicants in both fish and mammals. Halogens are corrosive both to metals and living tissues, are highly reactive, can be readily neutralized by metals, and react with organic matter to form toxic, persistent by-products such as dioxins and furans. Aldehydes may be carcinogenic to both human and animals upon repeated exposures, are corrosive, cross-link living tissues and many synthetic materials, and may lose efficacy when pathogens enzymatically adapt to them. Alcohols are flammable and volatile and can be enzymatically degraded by certain bacterial pathogens. Quats are highly irritating to mucous membranes and over time can induce pathogen resistance, especially if they are not alternated with functionally different disinfectants. In contrast, peracetic acid (PAA), a potent oxidizer, liberates hydrogen peroxide (itself a disinfectant), biodegrades to carbon dioxide, water and oxygen, and is at least as efficacious as contact biocides e.g., halogens and aldehydes. Nevertheless, the standard form of liquid PAA is highly corrosive, is neutralized by metals and organic matter, gives off noxious odours and must be stored in vented containers. For the reasons stated above, Bioxy formulations were developed, a series of powder forms of PAA, which are odourless, stable in storage and safe to transport and handle. They generate up to 10% PAA in situ when dissolved in water. A 0.2% aqueous solution of Bioxy (equivalent to 200 ppm PAA) effected a 6.76 log reduction in Methicillin-resistant Staphylococcus aureus (MRSA) within 2 minutes after application. A 5% aqueous solution of Bioxy achieved a 3.93 log reduction in the bovine tuberculosis bacillus

  19. Sustained antimicrobial activity and reduced toxicity of oxidative biocides through biodegradable microparticles.

    Science.gov (United States)

    Sofokleous, Panagiotis; Ali, Shanom; Wilson, Peter; Buanz, Asma; Gaisford, Simon; Mistry, Dharmit; Fellows, Adrian; Day, Richard M

    2017-12-01

    The spread of antibiotic-resistant pathogens requires new treatments. Small molecule precursor compounds that produce oxidative biocides with well-established antimicrobial properties could provide a range of new therapeutic products to combat resistant infections. The aim of this study was to investigate a novel biomaterials-based approach for the manufacture, targeted delivery and controlled release of a peroxygen donor (sodium percarbonate) combined with an acetyl donor (tetraacetylethylenediamine) to deliver local antimicrobial activity via a dynamic equilibrium mixture of hydrogen peroxide and peracetic acid. Entrapment of the pre-cursor compounds into hierarchically structured degradable microparticles was achieved using an innovative dry manufacturing process involving thermally induced phase separation (TIPS) that circumvented compound decomposition associated with conventional microparticle manufacture. The microparticles provided controlled release of hydrogen peroxide and peracetic acid that led to rapid and sustained killing of multiple drug-resistant organisms (methicillin-resistant Staphylococcus aureus and carbapenem-resistant Escherichia coli) without associated cytotoxicity in vitro nor intracutaneous reactivity in vivo. The results from this study demonstrate for the first time that microparticles loaded with acetyl and peroxygen donors retain their antimicrobial activity whilst eliciting no host toxicity. In doing so, it overcomes the detrimental effects that have prevented oxidative biocides from being used as alternatives to conventional antibiotics. The manuscript explores a novel approach to utilize the antimicrobial activity of oxidative species for sustained killing of multiple drug-resistant organisms without causing collateral tissue damage. The results demonstrate, for the first time, the ability to load pre-cursor compounds into porous polymeric structures that results in their release and conversion into oxidative species in a

  20. Mechanical performance of a biocompatible biocide soda-lime glass-ceramic.

    Science.gov (United States)

    López-Esteban, S; Bartolomé, J F; Dí Az, L A; Esteban-Tejeda, L; Prado, C; López-Piriz, R; Torrecillas, R; Moya, J S

    2014-06-01

    A biocompatible soda-lime glass-ceramic in the SiO2-Na2O-Al2O3-CaO-B2O3 system containing combeite and nepheline as crystalline phases, has been obtained at 750°C by two different routes: (i) pressureless sintering and (ii) Spark Plasma Sintering. The SPS glass-ceramic showed a bending strength, Weibull modulus, and toughness similar values to the cortical human bone. This material had a fatigue limit slightly superior to cortical bone and at least two times higher than commercial dental glass-ceramics and dentine. The in vitro studies indicate that soda-lime glass-ceramic is fully biocompatible. The in vivo studies in beagle jaws showed that implanted SPS rods presented no inflammatory changes in soft tissues surrounding implants in any of the 10 different cases after four months implantation. The radiological analysis indicates no signs of osseointegration lack around implants. Moreover, the biocide activity of SPS glass-ceramic versus Escherichia coli, was found to be >4log indicating that it prevents implant infections. Because of this, the SPS new glass-ceramic is particularly promising for dental applications (inlay, crowns, etc). Copyright © 2014 Elsevier Ltd. All rights reserved.

  1. Antifouling paint booster biocides (Irgarol 1051 and diuron) in marinas and ports of Bushehr, Persian Gulf.

    Science.gov (United States)

    Saleh, Abolfazl; Molaei, Saeideh; Sheijooni Fumani, Neda; Abedi, Ehsan

    2016-04-15

    In the present study, antifouling paint booster biocides, Irgarol 1051 and diuron were measured in ports and marinas of Bushehr, Iran. Results showed that in seawater samples taken from ports and marinas, Irgarol was found at the range of less than LOD to 63.4ngL(-1) and diuron was found to be at the range of less than LOD to 29.1ngL(-1) (in Jalali marina). 3,4-dichloroaniline (3,4-DCA), as a degradation product of diuron, was also analyzed and its maximum concentration was 390ngL(-1). Results for analysis of Irgarol 1051 in sediments showed a maximum concentration of 35.4ngg(-1) dry weight in Bandargah marina. A comparison between the results of this study and those of other published works showed that Irgarol and diuron pollutions in ports and marinas of Bushehr located in the Persian Gulf were less than the average of reports from other parts of the world. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Control of biofouling on reverse osmosis polyamide membranes modified with biocidal nanoparticles and antifouling polymer brushes

    KAUST Repository

    Rahaman, Md. Saifur

    2014-01-01

    Thin-film composite (TFC) polyamide reverse osmosis (RO) membranes are prone to biofouling due to their inherent physicochemical surface properties. In order to address the biofouling problem, we have developed novel surface coatings functionalized with biocidal silver nanoparticles (AgNPs) and antifouling polymer brushes via polyelectrolyte layer-by-layer (LBL) self-assembly. The novel surface coating was prepared with polyelectrolyte LBL films containing poly(acrylic acid) (PAA) and poly(ethylene imine) (PEI), with the latter being either pure PEI or silver nanoparticles coated with PEI (Ag-PEI). The coatings were further functionalized by grafting of polymer brushes, using either hydrophilic poly(sulfobetaine) or low surface energy poly(dimethylsiloxane) (PDMS). The presence of both LBL films and sulfobetaine polymer brushes at the interface significantly increased the hydrophilicity of the membrane surface, while PDMS brushes lowered the membrane surface energy. Overall, all surface modifications resulted in significant reduction of irreversible bacterial cell adhesion. In microbial adhesion tests with E. coli bacteria, a normalized cell adhesion in the range of only 4 to 16% on the modified membrane surfaces was observed. Modified surfaces containing silver nanoparticles also exhibited strong antimicrobial activity. Membranes coated with LBL films of PAA/Ag-PEI achieved over 95% inactivation of bacteria attached to the surface within 1 hour of contact time. Both the antifouling and antimicrobial results suggest the potential of using these novel surface coatings in controlling the fouling of RO membranes. © The Royal Society of Chemistry 2014.

  3. Impact of feed spacer and membrane modification by hydrophilic, bactericidal and biocidal coating on biofouling control

    KAUST Repository

    Araújo, Paula A.

    2012-06-01

    The influence of polydopamine- and polydopamine-. graft-poly(ethylene glycol)-coated feed spacers and membranes, copper-coated feed spacers, and commercially-available biostatic feed spacers on biofouling has been studied in membrane fouling simulators. Feed spacers and membranes applied in practical membrane filtration systems were used; biofouling development was monitored by feed channel pressure drop increase and biomass accumulation. Polydopamine and polydopamine-. g-PEG are hydrophilic surface modification agents expected to resist protein and bacterial adhesion, while copper feed spacer coatings and biocides infused in feed spacers are expected to restrict biological growth. Our studies showed that polydopamine and polydopamine-. g-PEG coatings on feed spacers and membranes, copper coatings on feed spacers, and a commercial biostatic feed spacer did not have a significant impact on feed channel pressure drop increase and biofilm accumulation as measured by ATP and TOC content. The studied spacer and membrane modifications were not effective for biofouling control; it is doubtful that feed spacer and membrane modification, in general, may be effective for biofouling control regardless of the type of applied coating. © 2012 Elsevier B.V.

  4. Decay model for biocide treatment of unballasted vessels: application for the Laurentian Great Lakes.

    Science.gov (United States)

    Sano, Larissa L; Bartell, Steven M; Landrum, Peter F

    2005-10-01

    A biocide decay model was developed to assess the potential efficacy and environmental impacts associated with using glutaraldehyde to treat unballasted overseas vessels trading on the Laurentian Great Lakes. The results of Monte Carlo simulations indicate that effective glutaraldehyde concentrations can be maintained for the duration of a vessel's oceanic transit (approximately 9-12 days): During this transit, glutaraldehyde concentrations were predicted to decrease by approximately 10% from initial treatment levels (e.g., 500 mgL(-1)). In terms of environmental impacts, mean glutaraldehyde concentrations released at Duluth-Superior Harbor, MN were predicted to be 100-fold lower than initial treatment concentrations, and ranged from 3.2 mgL(-1) (2 SD: 2.74) in April to 0.7 mgL(-1) (2 SD: 1.28) in August. Sensitivity analyses indicated that the re-ballasting dilution factor was the major variable governing final glutaraldehyde concentrations; however, lake surface temperatures became increasingly important during the warmer summer months.

  5. Determination of biocides and pesticides by on-line solid phase extraction coupled with mass spectrometry and their behaviour in wastewater and surface water

    International Nuclear Information System (INIS)

    Singer, Heinz; Jaus, Sylvia; Hanke, Irene; Lueck, Alfred; Hollender, Juliane; Alder, Alfredo C.

    2010-01-01

    This study focused on the input of hydrophilic biocides into the aquatic environment and on the efficiency of their removal in conventional wastewater treatment by a mass flux analysis. A fully automated method consisting of on-line solid phase extraction coupled to LC-ESI-MS/MS was developed and validated for the simultaneous trace determination of different biocidal compounds (1,2-benzisothiazoline-3-one (BIT), 3-Iodo-2-propynylbutyl-carbamate (IPBC), irgarol 1051 and 2-N-octyl-4-isothiazolinone (octhilinone, OIT), carbendazim, diazinon, diuron, isoproturon, mecoprop, terbutryn and terbutylazine) and pharmaceuticals (diclofenac and sulfamethoxazole) in wastewater and surface water. In the tertiary effluent, the highest average concentrations were determined for mecoprop (1010 ng/L) which was at comparable levels as the pharmaceuticals diclofenac (690 ng/L) and sulfamethoxazole (140 ng/L) but 1-2 orders of magnitude higher than the other biocidal compounds. Average eliminations for all compounds were usually below 50%. During rain events, increased residual amounts of biocidal contaminants are discharged to receiving surface waters. - Incomplete removal of biocides and pesticides during wastewater treatment.

  6. Determination of biocides and pesticides by on-line solid phase extraction coupled with mass spectrometry and their behaviour in wastewater and surface water

    Energy Technology Data Exchange (ETDEWEB)

    Singer, Heinz; Jaus, Sylvia; Hanke, Irene; Lueck, Alfred; Hollender, Juliane [Eawag, Swiss Federal Institute of Aquatic Science and Technology, Ueberlandstrasse 133, CH-8600 Duebendorf (Switzerland); Alder, Alfredo C., E-mail: alfredo.alder@eawag.c [Eawag, Swiss Federal Institute of Aquatic Science and Technology, Ueberlandstrasse 133, CH-8600 Duebendorf (Switzerland)

    2010-10-15

    This study focused on the input of hydrophilic biocides into the aquatic environment and on the efficiency of their removal in conventional wastewater treatment by a mass flux analysis. A fully automated method consisting of on-line solid phase extraction coupled to LC-ESI-MS/MS was developed and validated for the simultaneous trace determination of different biocidal compounds (1,2-benzisothiazoline-3-one (BIT), 3-Iodo-2-propynylbutyl-carbamate (IPBC), irgarol 1051 and 2-N-octyl-4-isothiazolinone (octhilinone, OIT), carbendazim, diazinon, diuron, isoproturon, mecoprop, terbutryn and terbutylazine) and pharmaceuticals (diclofenac and sulfamethoxazole) in wastewater and surface water. In the tertiary effluent, the highest average concentrations were determined for mecoprop (1010 ng/L) which was at comparable levels as the pharmaceuticals diclofenac (690 ng/L) and sulfamethoxazole (140 ng/L) but 1-2 orders of magnitude higher than the other biocidal compounds. Average eliminations for all compounds were usually below 50%. During rain events, increased residual amounts of biocidal contaminants are discharged to receiving surface waters. - Incomplete removal of biocides and pesticides during wastewater treatment.

  7. Reduction of healthcare-associated infections in a long-term care brain injury ward by replacing regular linens with biocidal copper oxide impregnated linens.

    Science.gov (United States)

    Lazary, A; Weinberg, I; Vatine, J-J; Jefidoff, A; Bardenstein, R; Borkow, G; Ohana, N

    2014-07-01

    Contaminated textiles in hospitals contribute to endogenous, indirect-contact, and aerosol transmission of nosocomial related pathogens. Copper oxide impregnated linens have wide-spectrum antimicrobial, antifungal, and antiviral properties. Our aim was to determine if replacing non-biocidal linens with biocidal copper oxide impregnated linens would reduce the rates of healthcare-associated infections (HAI) in a long-term care ward. We compared the rates of HAI in two analogous patient cohorts in a head injury care ward over two 6-month parallel periods before (period A) and after (period B) replacing all the regular non-biocidal linens and personnel uniforms with copper oxide impregnated biocidal products. During period B, in comparison to period A, there was a 24% reduction in the HAI per 1000 hospitalization-days (p38.5°C) per 1000 hospitalization-days (p<0.01), and a 32.8% reduction in total number of days of antibiotic administration per 1000 hospitalization-days (p<0.0001). Accordingly there was saving of approximately 27% in costs of antibiotics, HAI-related treatments, X-rays, disposables, labor, and laundry, expenses during period B. The use of biocidal copper oxide impregnated textiles in a long-term care ward may significantly reduce HAI, fever, antibiotic consumption, and related treatment costs. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  8. A New, Sensitive Marine Microalgal Recombinant Biosensor Using Luminescence Monitoring for Toxicity Testing of Antifouling Biocides

    Science.gov (United States)

    Sanchez-Ferandin, Sophie; Leroy, Fanny; Bouget, François-Yves

    2013-01-01

    In this study, we propose the use of the marine green alga Ostreococcus tauri, the smallest free-living eukaryotic cell known to date, as a new luminescent biosensor for toxicity testing in the environment. Diuron and Irgarol 1051, two antifouling biocides commonly encountered in coastal waters, were chosen to test this new biosensor along with two degradation products of diuron. The effects of various concentrations of the antifoulants on four genetic constructs of O. tauri (based on genes involved in photosynthesis, cell cycle, and circadian clock) were compared using 96-well culture microplates and a luminometer to automatically measure luminescence over 3 days. This was compared to growth inhibition of O. tauri wild type under the same conditions. Luminescence appeared to be more sensitive than growth inhibition as an indicator of toxicity. Cyclin-dependent kinase (CDKA), a protein involved in the cell cycle, fused to luciferase (CDKA-Luc) was found to be the most sensitive of the biosensors, allowing an accurate determination of the 50% effective concentration (EC50) after only 2 days (diuron, 5.65 ± 0.44 μg/liter; Irgarol 1015, 0.76 ± 0.10 μg/liter). The effects of the antifoulants on the CDKA-Luc biosensor were then compared to growth inhibition in natural marine phytoplankton. The effective concentrations of diuron and Irgarol 1051 were found to be similar, indicating that this biosensor would be suitable as a reliable ecotoxicological test. The advantage of this biosensor over cell growth inhibition testing is that the process can be easily automated and could provide a high-throughput laboratory approach to perform short-term toxicity tests. The ability to genetically transform and culture recombinant O. tauri gives it huge potential for screening many other toxic compounds. PMID:23144143

  9. Mechanisms of Persistence of the Ammonia-Oxidizing Bacteria Nitrosomonas to the Biocide Free Nitrous Acid.

    Science.gov (United States)

    Laloo, Andrew E; Wei, Justin; Wang, Dongbo; Narayanasamy, Shaman; Vanwonterghem, Inka; Waite, David; Steen, Jason; Kaysen, Anne; Heintz-Buschart, Anna; Wang, Qilin; Schulz, Benjamin; Nouwens, Amanda; Wilmes, Paul; Hugenholtz, Philip; Yuan, Zhiguo; Bond, Philip L

    2018-05-01

    Free nitrous acid (FNA) exerts a broad range of antimicrobial effects on bacteria, although susceptibility varies considerably among microorganisms. Among nitrifiers found in activated sludge of wastewater treatment processes (WWTPs), nitrite-oxidizing bacteria (NOB) are more susceptible to FNA compared to ammonia-oxidizing bacteria (AOB). This selective inhibition of NOB over AOB in WWTPs bypasses nitrate production and improves the efficiency and costs of the nitrogen removal process in both the activated sludge and anaerobic ammonium oxidation (Anammox) system. However, the molecular mechanisms governing this atypical tolerance of AOB to FNA have yet to be understood. Herein we investigate the varying effects of the antimicrobial FNA on activated sludge containing AOB and NOB using an integrated metagenomics and label-free quantitative sequential windowed acquisition of all theoretical fragment ion mass spectra (SWATH-MS) metaproteomic approach. The Nitrosomonas genus of AOB, on exposure to FNA, maintains internal homeostasis by upregulating a number of known oxidative stress enzymes, such as pteridine reductase and dihydrolipoyl dehydrogenase. Denitrifying enzymes were upregulated on exposure to FNA, suggesting the detoxification of nitrite to nitric oxide. Interestingly, proteins involved in stress response mechanisms, such as DNA and protein repair enzymes, phage prevention proteins, and iron transport proteins, were upregulated on exposure to FNA. In addition enzymes involved in energy generation were also upregulated on exposure to FNA. The total proteins specifically derived from the NOB genus Nitrobacter was low and, as such, did not allow for the elucidation of the response mechanism to FNA exposure. These findings give us an understanding of the adaptive mechanisms of tolerance within the AOB Nitrosomonas to the biocidal agent FNA.

  10. In-vitro archaeacidal activity of biocides against human-associated archaea.

    Directory of Open Access Journals (Sweden)

    Saber Khelaifia

    Full Text Available BACKGROUND: Several methanogenic archaea have been detected in the human intestinal microbiota. These intestinal archaea may contaminate medical devices such as colonoscopes. However, no biocide activity has been reported among these human-associated archaea. METHODOLOGY: The minimal archaeacidal concentration (MAC of peracetic acid, chlorhexidine, squalamine and twelve parent synthetic derivatives reported in this study was determined against five human-associated methanogenic archaea including Methanobrevibacter smithii, Methanobrevibacter oralis, Methanobrevibacter arboriphilicus, Methanosphaera stadtmanae, Methanomassiliicoccus luminyensis and two environmental methanogens Methanobacterium beijingense and Methanosaeta concilii by using a serial dilution technique in Hungates tubes. PRINCIPAL FINDINGS: MAC of squalamine derivative S1 was 0.05 mg/L against M. smithii strains, M. oralis, M. arboriphilicus, M. concilii and M. beijingense whereas MAC of squalamine and derivatives S2-S12 varied from 0.5 to 5 mg/L. For M. stadtmanae and M. luminyensis, MAC of derivative S1 was 0.1 mg/L and varied from 1 to ≥ 10 mg/L for squalamine and its parent derivatives S2-S12. Under the same experimental conditions, chlorhexidine and peracetic acid lead to a MAC of 0.2 and 1.5 mg/L, respectively against all tested archaea. CONCLUSIONS/SIGNIFICANCE: Squalamine derivative S1 exhibited a 10-200 higher archaeacidal activity than other tested squalamine derivatives, on the majority of human-associated archaea. As previously reported and due to their week corrosivity and their wide spectrum of antibacterial and antifungal properties, squalamine and more precisely derivative S1 appear as promising compounds to be further tested for the decontamination of medical devices contaminated by human-associated archaea.

  11. International Space Station (ISS) Internal Active Thermal Control System (IATCS) New Biocide Selection, Qualification and Implementation

    Science.gov (United States)

    Wilson, Mark E.; Cole, Harold E.; Rector, Tony; Steele, John; Varsik, Jerry

    2011-01-01

    The Internal Active Thermal Control System (IATCS) aboard the International Space Station (ISS) is primarily responsible for the removal of heat loads from payload and system racks. The IATCS is a water based system which works in conjunction with the EATCS (External ATCS), an ammonia based system, which are interfaced through a heat exchanger to facilitate heat transfer. On-orbit issues associated with the aqueous coolant chemistry began to occur with unexpected increases in CO2 levels in the cabin. This caused an increase in total inorganic carbon (TIC), a reduction in coolant pH, increased corrosion, and precipitation of nickel phosphate. These chemical changes were also accompanied by the growth of heterotrophic bacteria that increased risk to the system and could potentially impact crew health and safety. Studies were conducted to select a biocide to control microbial growth in the system based on requirements for disinfection at low chemical concentration (effectiveness), solubility and stability, material compatibility, low toxicity to humans, compatibility with vehicle environmental control and life support systems (ECLSS), ease of application, rapid on-orbit measurement, and removal capability. Based on these requirements, ortho-phthalaldehyde (OPA), an aromatic dialdehyde compound, was selected for qualification testing. This paper presents the OPA qualification test results, development of hardware and methodology to safely apply OPA to the system, development of a means to remove OPA, development of a rapid colorimetric test for measurement of OPA, and the OPA on-orbit performance for controlling the growth of microorganisms in the ISS IATCS since November 3, 2007.

  12. Pesticides and biocides in a karst catchment: Identification of contaminant sources and related flow components

    Science.gov (United States)

    Wagner, Thomas; Bollmann, Ulla E.; Bester, Kai; Birk, Steffen

    2013-04-01

    Karst aquifers are widely used as drinking water resources. However, their high vulnerability to chemical and bacterial contamination due to the heterogeneity in aquifer properties (highly conductive solution conduits embedded in the less conductive fissured rock) is difficult to assess and thus poses major challenges to the management of karst water resources. Contamination of karst springs by organic micro-pollutants has been observed in recent studies. Within this study the water from different springs draining one karst aquifer as well as the main sinking stream replenishing it were analysed before, during and after a storm water event in order to examine the occurrence of different pesticides and biocides. Contaminants from both urban as well as agricultural origin could be detected in the water with concentrations in the low ng/L range (tebuconazole, carbendazim, diuron, isoproturon, terbutryn, atrazine, dichlorobenzamide (BAM), which is a metabolite of dichlobenil). While some compounds could be followed from the sinking stream to the springs (e.g. dichlorobenzamide) some seem to have a source in the autogenic recharge from the karst plateau (Tebuconazole: wood preservative in buildings). These compounds appear to be related to fast flow components with residence times in the order of days, which are known from a number of tracer tests with fluorescent dyes. However, the occurrence of the pesticide atrazine (banned since 1995 in Austria) in the springs, while on the other hand no current input into the karst occurs, shows that some compounds have long residence times in the karst aquifer. These differences in residence times can hardly be attributed to differences in physico-chemical properties of the compounds and must thus be due to the presence of slow and fast flow components. This is in agreement with the duality of karst aquifers due to highly conductive networks of solution conduits embedded in less conductive fissured carbonate rocks.

  13. Bromination vis-a-vis chlorination as a biocide feasibility study

    International Nuclear Information System (INIS)

    Upadhyay, S.K.; Nagaigh, N.; Mittal, S.

    2000-01-01

    Water is used extensively as a cooling medium in various heat transfer equipment's of a power industry such as condenser, heat exchangers and cooling towers. At elevated temperature, the breeding of microbiological growth can form slimes, underneath of this, accelerated corrosion can take place resulting into sudden and catastrophic failure of equipment's. The microbiological growth unchecked in the various systems especially in low velocity areas can lead to large growth of micro organisms such as algae which can even reduce the flow of the fluid thus affecting the efficiency of plant equipment's. Therefore, chlorination is a mandatory requirement in industrial cooling water to reduce biofouling in heat transfer equipment's. The chlorination in drinking water produces germicidal effect and thus reduces the bacterial counts. At NAPS the water quality is good and mild doses of chlorine (5 ppm) two times a day, as envisaged in design is noticed to be satisfactory. The chlorination of recirculating condenser cooling water presently is being done with the established doses for a fixed time twice a day. Some of the problems noticed with the chlorination process are : Corrosion of constructional material of chlorination plant and equipment's and pipelines causing large input of efforts on maintenance for keeping high availability of the chlorination plant. In addition to this, the leakages in the equipment could be a potential safety hazard. The effectiveness of chlorine is observed to be less in alkaline pH (above 9.0) as encountered at NAPS. This results is large quantities of chlorine injection for extended periods. The cost of chlorine and bleaching powder keeps fluctuating in the market as noticed in past few years. Many a times this results in scarcity of chlorine/bleaching powder causing interruption in biofouling control programme. Hence it was felt prudent to work on the alternative biocides which could be cost effective, non-polluting and nature and user

  14. Genetic relatedness, antimicrobial and biocide susceptibility comparative analysis of methicillin-resistant and -susceptible Staphylococcus pseudintermedius from Portugal.

    Science.gov (United States)

    Couto, Natacha; Belas, Adriana; Couto, Isabel; Perreten, Vincent; Pomba, Constança

    2014-08-01

    Forty methicillin-resistant and -susceptible Staphylococcus pseudintermedius (MRSP and MSSP, respectively) from colonization and infection in dogs and cats were characterized for clonality, antimicrobial, and biocide susceptibility. MSSP were genetically more diverse than MRSP by multi-locus sequence typing and pulsed-field gel electrophoresis. Three different spa types (t06, t02, t05) and two SCCmec types (II-III and V) were detected in the MRSP isolates. All MRSP and two MSSP strains were multidrug-resistant. Several antibiotic resistance genes (mecA, blaZ, tet(M), tet(K), aac(6')-Ie-aph(2')-Ia, aph(3')-III, ant(6)-Ia, sat4, erm(B), lnu(A), dfr(G), and catp(C221)) were identified by microarray and double mutations in the gyrA and grlA genes and a single mutation in the rpoB gene were detected by sequence analysis. No differences were detected between MSSP and MRSP in the chlorhexidine acetate (CHA) minimum inhibitory concentrations (MICs). However, two MSSP had elevated MIC to triclosan (TCL) and one to benzalkonium chloride and ethidium bromide. One MSSP isolate harboured a qacA gene, while in another a qacB gene was detected. None of the isolates harboured the sh-fabI gene. Three of the biocide products studied had high bactericidal activity (Otodine(®), Clorexyderm Spot Gel(®), Dermocanis Piocure-M(®)), while Skingel(®) failed to achieve a five log reduction in the bacterial counting. S. pseudintermedius have become a serious therapeutic challenge in particular if methicillin- resistance and/or multidrug-resistance are involved. Biocides, like CHA and TCL, seem to be clinically effective and safe topical therapeutic options.

  15. Assessment of the risk posed by the antifouling booster biocides Irgarol 1051 and diuron to freshwater macrophytes.

    Science.gov (United States)

    Lambert, S J; Thomas, K V; Davy, A J

    2006-05-01

    Antifouling paints are used to reduce the attachment of living organisms to the submerged surfaces of ships, boats and aquatic structures, usually by the release of a biocide. Two 'booster' biocides in common use are the triazine herbicide Irgarol 1051 (N-2-methylthio-4-tert-butylamino-6-cyclopropylamino-s-triazine), and diuron (1-(3,4-dichlorophenyl)-3,3-dimethylurea), which are designed to inhibit algal photosynthesis. Previous research has been directed at the effects of these compounds in marine and estuarine environments. In 2001 we sampled the main rivers and shallow freshwater lakes (Broads) of East Anglia UK for Irgarol 1051, its metabolite GS26575 (2-methylamino-4-tert-butylamino-6-amino-s-triazine) and diuron in order to establish the baseline environmental concentrations of these compounds in freshwater systems of eastern UK and to investigate their possible effects on aquatic plants. Irgarol 1051, GS26575 and diuron were found in water samples collected from 21 locations. The highest concentrations were found in the Norfolk and Suffolk Broads in May. The rivers Great Ouse, Wissey, Bure and Yare also contained all three compounds, as did the Great Ouse Cut-off Channel. The toxicity of these biocides to three macrophyte species (Apium nodiflorum, Chara vulgaris, and Myriophyllum spicatum) was investigated. Deleterious effects on relative growth rate, the maximum quantum efficiency (Fv/Fm) of photosystem II and, for Apium, root mass production were found. C. vulgaris was generally most sensitive; growth, especially of roots, was strongly affected in A. nodiflorum; growth rate of M. spicatum was sensitive to diuron. No observed effect concentrations (NOEC) were interpolated using standard toxicological analysis. These were compared with measured environmental concentrations (MEC) to determine the ranges of risk quotients (MEC/NOEC). Both Irgarol 1051 and diuron represented significant risks to A. nodiflorum and C. vulgaris in this area.

  16. Toxicity of antifouling biocides to the intertidal harpacticoid copepod Tigriopus japonicus (Crustacea, Copepoda): Effects of temperature and salinity

    International Nuclear Information System (INIS)

    Kwok, K.W.H.; Leung, K.M.Y.

    2005-01-01

    Intertidal harpacticoid copepods are commonly used in eco-toxicity tests worldwide. They predominately live in mid-high shore rock pools and often experience a wide range of temperature and salinity fluctuation. Most eco-toxicity tests are conducted at fixed temperature and salinity and thus the influence of these environmental factors on chemical toxicity is largely unknown. This study investigated the combined effect of temperature and salinity on the acute toxicity of the copepod Tigriopus japonicus against two common biocides, copper (Cu) and tributyltin (TBT) using a 2 x 3 x 4 factorial design (i.e. two temperatures: 25 and 35 o C; three salinities: 15.0 per mille , 34.5 per mille and 45.0 per mille ; three levels of the biocide plus a control). Copper sulphate and tributyltin chloride were used as the test chemicals while distilled water and acetone were utilised as solvents for Cu and TBT respectively. 96h-LC50s of Cu and TBT were 1024 and 0.149 μg l -1 respectively (at 25 o C; 34.5 per mille ) and, based on these results, nominal biocide concentrations of LC0 (i.e. control), LC30, LC50 and LC70 were employed. Analysis of Covariance using 'concentration' as the covariate and both 'temperature' and 'salinity' as fixed factors, showed a significant interaction between temperature and salinity effects for Cu, mortality increasing with temperature but decreasing with elevated salinity. A similar result was revealed for TBT. Both temperature and salinity are, therefore, important factors affecting the results of acute eco-toxicity tests using these marine copepods. We recommend that such eco-toxicity tests should be conducted at a range of environmentally realistic temperature/salinity regimes, as this will enhance the sensitivity of the test and improve the safety margin in line with the precautionary principle

  17. Toxicity of antifouling biocides to the intertidal harpacticoid copepod Tigriopus japonicus (Crustacea, Copepoda): Effects of temperature and salinity

    Energy Technology Data Exchange (ETDEWEB)

    Kwok, K.W.H. [Swire Institute of Marine Science, Department of Ecology and Biodiversity, University of Hong Kong, Pokfulam, Hong Kong (China); Leung, K.M.Y. [Swire Institute of Marine Science, Department of Ecology and Biodiversity, University of Hong Kong, Pokfulam, Hong Kong (China)]. E-mail: kmyleung@hkucc.hku.hk

    2005-07-01

    Intertidal harpacticoid copepods are commonly used in eco-toxicity tests worldwide. They predominately live in mid-high shore rock pools and often experience a wide range of temperature and salinity fluctuation. Most eco-toxicity tests are conducted at fixed temperature and salinity and thus the influence of these environmental factors on chemical toxicity is largely unknown. This study investigated the combined effect of temperature and salinity on the acute toxicity of the copepod Tigriopus japonicus against two common biocides, copper (Cu) and tributyltin (TBT) using a 2 x 3 x 4 factorial design (i.e. two temperatures: 25 and 35 {sup o}C; three salinities: 15.0 per mille , 34.5 per mille and 45.0 per mille ; three levels of the biocide plus a control). Copper sulphate and tributyltin chloride were used as the test chemicals while distilled water and acetone were utilised as solvents for Cu and TBT respectively. 96h-LC50s of Cu and TBT were 1024 and 0.149 {mu}g l{sup -1} respectively (at 25 {sup o}C; 34.5 per mille ) and, based on these results, nominal biocide concentrations of LC0 (i.e. control), LC30, LC50 and LC70 were employed. Analysis of Covariance using 'concentration' as the covariate and both 'temperature' and 'salinity' as fixed factors, showed a significant interaction between temperature and salinity effects for Cu, mortality increasing with temperature but decreasing with elevated salinity. A similar result was revealed for TBT. Both temperature and salinity are, therefore, important factors affecting the results of acute eco-toxicity tests using these marine copepods. We recommend that such eco-toxicity tests should be conducted at a range of environmentally realistic temperature/salinity regimes, as this will enhance the sensitivity of the test and improve the safety margin in line with the precautionary principle.

  18. Enhanced Biocide Treatments with D-amino Acid Mixtures against a Biofilm Consortium from a Water Cooling Tower.

    Science.gov (United States)

    Jia, Ru; Li, Yingchao; Al-Mahamedh, Hussain H; Gu, Tingyue

    2017-01-01

    Different species of microbes form mixed-culture biofilms in cooling water systems. They cause microbiologically influenced corrosion (MIC) and biofouling, leading to increased operational and maintenance costs. In this work, two D-amino acid mixtures were found to enhance two non-oxidizing biocides [tetrakis hydroxymethyl phosphonium sulfate (THPS) and NALCO 7330 (isothiazoline derivatives)] and one oxidizing biocide [bleach (NaClO)] against a biofilm consortium from a water cooling tower in lab tests. Fifty ppm (w/w) of an equimass mixture of D-methionine, D-leucine, D-tyrosine, D-tryptophan, D-serine, D-threonine, D-phenylalanine, and D-valine (D8) enhanced 15 ppm THPS and 15 ppm NALCO 7330 with similar efficacies achieved by the 30 ppm THPS alone treatment and the 30 ppm NALCO 7330 alone treatment, respectively in the single-batch 3-h biofilm removal test. A sequential treatment method was used to enhance bleach because D-amino acids react with bleach. After a 4-h biofilm removal test, the sequential treatment of 5 ppm bleach followed by 50 ppm D8 achieved extra 1-log reduction in sessile cell counts of acid producing bacteria, sulfate reducing bacteria, and general heterotrophic bacteria compared with the 5 ppm bleach alone treatment. The 10 ppm bleach alone treatment showed a similar efficacy with the sequential treatment of 5 ppm bleach followed by 50 ppm D8. The efficacy of D8 was found better than that of D4 (an equimass mixture of D-methionine, D-leucine, D-tyrosine, and D-tryptophan) in the enhancement of the three individual biocides against the biofilm consortium.

  19. Enhanced Biocide Treatments with D-amino Acid Mixtures against a Biofilm Consortium from a Water Cooling Tower

    Directory of Open Access Journals (Sweden)

    Ru Jia

    2017-08-01

    Full Text Available Different species of microbes form mixed-culture biofilms in cooling water systems. They cause microbiologically influenced corrosion (MIC and biofouling, leading to increased operational and maintenance costs. In this work, two D-amino acid mixtures were found to enhance two non-oxidizing biocides [tetrakis hydroxymethyl phosphonium sulfate (THPS and NALCO 7330 (isothiazoline derivatives] and one oxidizing biocide [bleach (NaClO] against a biofilm consortium from a water cooling tower in lab tests. Fifty ppm (w/w of an equimass mixture of D-methionine, D-leucine, D-tyrosine, D-tryptophan, D-serine, D-threonine, D-phenylalanine, and D-valine (D8 enhanced 15 ppm THPS and 15 ppm NALCO 7330 with similar efficacies achieved by the 30 ppm THPS alone treatment and the 30 ppm NALCO 7330 alone treatment, respectively in the single-batch 3-h biofilm removal test. A sequential treatment method was used to enhance bleach because D-amino acids react with bleach. After a 4-h biofilm removal test, the sequential treatment of 5 ppm bleach followed by 50 ppm D8 achieved extra 1-log reduction in sessile cell counts of acid producing bacteria, sulfate reducing bacteria, and general heterotrophic bacteria compared with the 5 ppm bleach alone treatment. The 10 ppm bleach alone treatment showed a similar efficacy with the sequential treatment of 5 ppm bleach followed by 50 ppm D8. The efficacy of D8 was found better than that of D4 (an equimass mixture of D-methionine, D-leucine, D-tyrosine, and D-tryptophan in the enhancement of the three individual biocides against the biofilm consortium.

  20. Effects of marine microbial biofilms on the biocide release rate from antifouling paints – A model-based analysis

    DEFF Research Database (Denmark)

    Yebra, Diego Meseguer; Kiil, Søren; Erik Weinell, Claus

    2006-01-01

    The antifouling (AF) paint model of Kiil et al. [S. Kiil, C.E. Weinell, M.S. Pedersen, K. Dam-Johansen, Analysis of self-polishing antifouling paints using rotary experiments and mathematical modelling, Ind. Eng. Chem. Res. 40 (2001) 3906-3920] and the simplified biofilm. growth model of Gujer...... and Warmer [W. Gujer, O. Warmer, Modeling mixed population biofilms, in: W.G. Characklis, K.C. Marshall (Eds.), Biofilms, Wiley-Interscience, New York, 1990] are used to provide a reaction engineering-based insight to the effects of marine microbial slimes on biocide leaching and, to a minor extent...

  1. Regulatory requirements for biocides on the market in the European Union according to Directive 98/8/EC.

    Science.gov (United States)

    Rasmussen, K; Chemin, P; Haastrup, P

    1999-06-30

    In early 1998, the European Commission and Parliament adopted a new Directive concerning the placing on the market of biocidal products. The Directive is to be implemented in the member states by May 2000. The member states are currently concerned with the national implementation into legislation whereas the Commission is setting up the proposal for a review programme for the existing active substances and the products in which they are used. This paper describes the effort currently undertaken (up to the end of December 1998) to define the procedures to be used and characterise the substances covered. Copyright 1999 Elsevier Science B.V.

  2. Current Knowledge on Listeria monocytogenes Biofilms in Food-Related Environments: Incidence, Resistance to Biocides, Ecology and Biocontrol

    Directory of Open Access Journals (Sweden)

    Pedro Rodríguez-López

    2018-06-01

    Full Text Available Although many efforts have been made to control Listeria monocytogenes in the food industry, growing pervasiveness amongst the population over the last decades has made this bacterium considered to be one of the most hazardous foodborne pathogens. Its outstanding biocide tolerance capacity and ability to promiscuously associate with other bacterial species forming multispecies communities have permitted this microorganism to survive and persist within the industrial environment. This review is designed to give the reader an overall picture of the current state-of-the-art in L. monocytogenes sessile communities in terms of food safety and legislation, ecological aspects and biocontrol strategies.

  3. Environmentally friendly procedure based on VA-MSPD for the determination of booster biocides in fish tissue.

    Science.gov (United States)

    Vieira, Augusto A; Caldas, Sergiane S; Escarrone, Ana Laura Venquiaruti; Arias, Jean Lucas de Oliveira; Primel, Ednei Gilberto

    2018-03-01

    Booster biocides have been widely applied to ships and other submerged structures. These compounds can be released into the marine environment as the result of vessel hull leaching and may remain in different environmental compartments. This study aimed at introducing an environmentally friendly procedure for the extraction of irgarol and diuron from fish samples by vortex-assisted matrix solid phase dispersion (VA-MSPD) with detection by liquid chromatography tandem mass spectrometry. Different types of solid supports and solvents were evaluated. The best results were found when 0.5g mussel shell, 0.5g sodium sulfate and 5mL ethanol were used. Analytical recoveries ranged from 81 to 110%, with RSD below 10%, whereas the matrix effect was between -17 and 1% (for all samples under study). LOQ values of irgarol and diuron were 5 and 50ngg -1 , respectively. The method under investigation proved to be a promising alternative to controlling contamination of fish by booster biocides, with low consumption of biodegradable reagents. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Biocidal Potential and Chemical Composition of Industrial Essential Oils from Hyssopus officinalis, Lavandula × intermedia var. Super, and Santolina chamaecyparissus.

    Science.gov (United States)

    Ortiz de Elguea-Culebras, Gonzalo; Sánchez-Vioque, Raúl; Berruga, María Isabel; Herraiz-Peñalver, David; González-Coloma, Azucena; Andrés, María Fé; Santana-Méridas, Omar

    2018-01-01

    This work presents the biocidal (insecticidal, ixodicidal, nematicidal, and phytotoxic) effects and chemical compositions of three essential oils obtained from the industrial steam distillation (IEOs) of hyssop (Hyssopus officinalis L.), lavandin (Lavandula × intermedia or L. × hybrida var. Super), and cotton lavender (Santolina chamaecyparissus L.). Their chemical composition analyzed by gas chromatography coupled to mass spectrometry showed 1,8-cineole (53%) and β-pinene (16%) as the major components of H. officinalis, linalyl acetate (38%) and linalool (29%) of L. × intermedia; and 1,8-cineole (10%) and 8-methylene-3-oxatricyclo[5.2.0.0 2,4 ]nonane (8%) in S. chamaecyparissus. The biocidal tests showed that L. × intermedia IEO was the most active against the insect Spodoptera littoralis and toxic to the tick Hyalomma lusitanicum, IEO of H. officinalis was strongly active against S. littoralis, and finally, S. chamaecyparissus IEO was a strong antifeedant against the aphid Rhopalosiphum padi, toxic to H. lusitanicum and with moderate effects against Leptinotarsa decemlineata, S. littoralis, and Lolium perenne. © 2018 Wiley-VHCA AG, Zurich, Switzerland.

  5. Supplement to the methodology for risk evaluation: Emission Scenario Document for Product Type 2: Private and public health area disinfectants and other biocidal products (sanitary and medical sector)

    NARCIS (Netherlands)

    Poel P van der; CSR

    2001-01-01

    Dit rapport is een aangepaste versie van RIVM rapport 601450 002. Herziening vond plaats in het kader van het project "Verzameling, herziening en ontwikkeling van biocide emissie scenario's voor het milieu" (werkgroep EUBEES). Het rapport bevat een beschrijving van de behandelde

  6. Supplement to the methodology for risk evaluation: Emission Scenario Document for Product Type 2: Private and public health area disinfectants and other biocidal products (sanitary and medical sector)

    NARCIS (Netherlands)

    Poel P van der; CSR

    2001-01-01

    This report is produced in the framework of EUBEES (EU working group on Gathering, Review and Development of Environmental Emission Scenarios for Biocides). It contains descriptions of the specific applications mentioned in the title and the accompanying emission scenarios. Where appropriate

  7. Structure, tribocorrosion and biocide characterization of Ca, P and I containing TiO{sub 2} coatings developed by plasma electrolytic oxidation

    Energy Technology Data Exchange (ETDEWEB)

    Sáenz de Viteri, V., E-mail: virginia.saenzdeviteri@tekniker.es [IK4-Tekniker, Polo Tecnológico de Eibar, Calle Iñaki Goenaga, 5, Eibar 20600 (Spain); Bayón, R.; Igartua, A. [IK4-Tekniker, Polo Tecnológico de Eibar, Calle Iñaki Goenaga, 5, Eibar 20600 (Spain); Barandika, G. [Departamento de Química Inorgánica, Facultad de Ciencia y Tecnología, Universidad del País Vasco, UPV/EHU, Apartado 644, Bilbao E-48080 (Spain); Moreno, J. Esteban; Peremarch, C. Pérez-Jorge; Pérez, M. Martínez [Department of Clinical Microbiology, IIS-Fundación Jiménez Díaz, Av. Reyes Católicos 2, Madrid 28040 (Spain)

    2016-03-30

    Graphical abstract: - Highlights: • Ca, P and I doped TiO{sub 2} coatings were developed by means of plasma electrolytic oxidation (PEO) technique. • Microstructure and chemical composition of the developed coating were in depth analyzed. • The effect of wear-corrosion synergy was studied through tribocorrosion tests. • Antibacterial efficiency of iodine as biocide agent was analyzed by means of bacterial adhesion study. • A TiO{sub 2} coating with improved wear-corrosion resistance, suitable surface for cell adhesion and biocide properties was achieved. - Abstract: In hip joint implants, in particular in the stems, wear-corrosion effects can accelerate the degradation of the biomaterial. The lack of osseointegration and the risk of contracting implant-associated infections may be other reasons for a premature failure of the implant. In this work, TiO{sub 2} coatings have been developed by means of plasma electrolytic oxidation (PEO) technique in order to achieve wear-resistant hard coatings with osseointegration ability and biocide characteristics. During the PEO process, elements that favor cell growth, like Ca and P, were introduced into the coating. With the purpose of providing the coating with antibacterial properties iodine was added like biocide agent. The microstructure and chemical composition of the developed coatings were analyzed in order to see if the surface of the films was suitable for the cell attachment. The effect of wear-corrosion synergy was studied by means of tribocorrosion tests. Finally, the biocide capacity of iodine against Staphylococcus aureus and Staphylococcus epidermidis was analyzed through bacterial adhesion tests. High wear and corrosion resistance was shown in one of the developed coatings. The achieved surface microstructures seem to be appropriate to improve the osseointegration with proper pore size and porosity index. The antibacterial capacity of iodine was confirmed for S. epidermidis.

  8. Biocide plants as a sustainable tool for the control of pests and pathogens in vegetable cropping systems

    Directory of Open Access Journals (Sweden)

    Trifone D'Addabbo

    2014-11-01

    Full Text Available Synthetic pesticides have played a major role in crop protection related to the intensification of agricultural systems. In the recent years, environmental side effects and health concerns raised by an indiscriminate use have led the EU to the ban of many synthetic pesticides. As a result of this drastic revision, currently there is a strong need for new and alternative pest control methods. An interesting source of biorational pesticides may be represented by the biocidal compounds naturally occurring in plants as products of the secondary metabolism. Groups of plant secondary metabolites most promising for the development of pesticidal formulations are glucosinolates, saponins, and more generally terpenoid phytoconstituents, such as essential oil and their constituents. Glucosinolates are thioglucosidic secondary metabolites occurring mainly in the Brassicaceae and, at a less extent, in Capparidaceae families. The incorporation of glucosinolate- containing plant material into the soil results in degradation products highly toxic to soilborne pest, pathogens and weeds. This practice, known as biofumigation, may be considered as an ecological alternative to soil toxic fumigants. Plant-derived saponins are triterpene glycosides present in top and root tissues of plant species of the families Leguminosae, Alliaceae, Asteraceae, Polygalaceae and Agavaceae. Saponins and saponin-rich plant materials have been also reported for a biocidal activity on phytoparasites and soilborne plant pathogens. Essential oils are volatile, natural, heterogeneous mixtures of single substances, mainly terpenes and phenolics, formed as secondary metabolites by aromatic plants belonging to several botanical families. Among terpenes, limonoid triterpenes have been demonstrated to possess interesting insecticidal, nematicidal and antifungal properties. Occurrence of these compounds is mainly limited to Meliaceae and Rutaceae. Alkaloids, phenolics, cyanogenic glucosides

  9. Risk assessment of herbicides and booster biocides along estuarine continuums in the Bay of Vilaine area (Brittany, France).

    Science.gov (United States)

    Caquet, Th; Roucaute, M; Mazzella, N; Delmas, F; Madigou, C; Farcy, E; Burgeot, Th; Allenou, J-P; Gabellec, R

    2013-02-01

    A 2-year study was implemented to characterize the contamination of estuarine continuums in the Bay of Vilaine area (NW Atlantic Coast, Southern Brittany, France) by 30 pesticide and biocide active substances and metabolites. Among these, 11 triazines (ametryn, atrazine, desethylatrazine, desethylterbuthylazine, desisopropyl atrazine, Irgarol 1051, prometryn, propazine, simazine, terbuthylazine, and terbutryn), 10 phenylureas (chlortoluron, diuron, 1-(3,4-dichlorophenyl)-3-methylurea, fenuron, isoproturon, 1-(4-isopropylphenyl)-3-methylurea, 1-(4-isopropylphenyl)-urea, linuron, metoxuron, and monuron), and 4 chloroacetanilides (acetochlor, alachlor, metolachlor, and metazachlor) were detected at least once. The objectives were to assess the corresponding risk for aquatic primary producers and to provide exposure information for connected studies on the responses of biological parameters in invertebrate sentinel species. The risk associated with contaminants was assessed using risk quotients based on the comparison of measured concentrations with original species sensitivity distribution-derived hazardous concentration values. For EU Water Framework Directive priority substances, results of monitoring were also compared with regulatory Environmental Quality Standards. The highest residue concentrations and risks for primary producers were recorded for diuron and Irgarol 1051 in Arzal reservoir, close to a marina. Diuron was present during almost the all survey periods, whereas Irgarol 1051 exhibited a clear seasonal pattern, with highest concentrations recorded in June and July. These results suggest that the use of antifouling biocides is responsible for a major part of the contamination of the lower part of the Vilaine River course for Irgarol 1051. For diuron, agricultural sources may also be involved. The presence of isoproturon and chloroacetanilide herbicides on some dates indicated a significant contribution of the use of plant protection products in

  10. Environmental risk assessment of biocidal products: identification of relevant components and reliability of a component-based mixture assessment.

    Science.gov (United States)

    Coors, Anja; Vollmar, Pia; Heim, Jennifer; Sacher, Frank; Kehrer, Anja

    2018-01-01

    Biocidal products are mixtures of one or more active substances (a.s.) and a broad range of formulation additives. There is regulatory guidance currently under development that will specify how the combined effects of the a.s. and any relevant formulation additives shall be considered in the environmental risk assessment of biocidal products. The default option is a component-based approach (CBA) by which the toxicity of the product is predicted from the toxicity of 'relevant' components using concentration addition. Hence, unequivocal and practicable criteria are required for identifying the 'relevant' components to ensure protectiveness of the CBA, while avoiding unnecessary workload resulting from including by default components that do not significantly contribute to the product toxicity. The present study evaluated a set of different criteria for identifying 'relevant' components using confidential information on the composition of 21 wood preservative products. Theoretical approaches were complemented by experimentally testing the aquatic toxicity of seven selected products. For three of the seven tested products, the toxicity was underestimated for the most sensitive endpoint (green algae) by more than factor 2 if only the a.s. were considered in the CBA. This illustrated the necessity of including at least some additives along with the a.s. Considering additives that were deemed 'relevant' by the tentatively established criteria reduced the underestimation of toxicity for two of the three products. A lack of data for one specific additive was identified as the most likely reason for the remaining toxicity underestimation of the third product. In three other products, toxicity was overestimated by more than factor 2, while prediction and observation fitted well for the seventh product. Considering all additives in the prediction increased only the degree of overestimation. Supported by theoretical calculations and experimental verifications, the present

  11. Micropollutants in closed life-support systems: the case of triclosan, a biocide excreted via urine

    Science.gov (United States)

    Mastroleo, Felice; Pycke, Benny; Boon, Nico; de Wever, Heleen; Hendrickx, Larissa; Mastroleo, Felice; Wattiez, Ruddy; Mergeay, Max; Verstraete, Willy

    OBJECTIVES: The impact of triclosan on the growth and physiology of the bacterium Rhodospirillum rubrum was studied in the frame of the regenerative life-support system, Micro- Ecological Life Support System Alternative (MELiSSA). A wide range of compounds, such as steroid hormones, pharmaceuticals and personal care products, might enter the life support system via the excrements that are to be treated and recycled. Triclosan was chosen as the first compound to be tested because MELiSSA is a closed system, which is consequently particularly sensitive to compounds inhibiting the microbial metabolism. Because triclosan is increasingly used as an antimicrobial biocide in hygienic formulations (such as toothpaste, mouthwash, deodorants, etc.) and due to its chemical stability, it is considered an emerging pollutant in terrestrial ecosystems. METHODS: In a first phase, the triclosan concentration expected in the life-support system was estimated, the Minimal Inhibitory Concentration (MIC) was determined via plating, and the effect on growth kinetics was assessed by comparing growth parameters in the Gompertz model. In a second phase, the secondary effects of triclosan on cell physiology and gene expression were studied through flow-cytometry and microarray analyses, respectively. RESULTS: Based on the pharmacokinetic data from literature, the predicted concentration range is estimated to be 6-25µg/L triclosan in the Rhodospirillum rubrum compartment of the MELiSSA. The minimal inhibitory concentration of triclosan was determined to be 71 µg/L after 7 days of exposure on Sistrom medium. Upon exposure to 50-200µg/L triclosan, triclosan-resistant mutants of Rhodospirillum rubrum arose spontaneously at high frequency (3.1 ∗ 10 - 4). Analysis of the growth kinetics of the wild-type revealed that triclosan causes an important elongation of the lag-phase and a decrease in growth rate. At concentrations higher than 75mg/L(LD = 500mg/L), triclosan is bactericidal to wild

  12. The 9.2 ka event in Asian summer monsoon area: the strongest millennial scale collapse of the monsoon during the Holocene

    Science.gov (United States)

    Zhang, Wenchao; Yan, Hong; Dodson, John; Cheng, Peng; Liu, Chengcheng; Li, Jianyong; Lu, Fengyan; Zhou, Weijian; An, Zhisheng

    2018-04-01

    Numerous Holocene paleo-proxy records exhibit a series of centennial-millennial scale rapid climatic events. Unlike the widely acknowledged 8.2 ka climate anomaly, the likelihood of a significant climate excursion at around 9.2 cal ka BP, which has been notably recognized in some studies, remains to be fully clarified in terms of its magnitude and intensity, as well as its characteristics and spatial distributions in a range of paleoclimatic records. In this study, a peat sediment profile from the Dajiuhu Basin in central China was collected with several geochemical proxies and a pollen analysis carried out to help improve understanding of the climate changes around 9.2 cal ka BP. The results show that the peat development was interrupted abruptly at around 9.2 cal ka BP, when the chemical weathering strength decreased and the tree-pollen declined. This suggests that a strong drier regional climatic event occurred at around 9.2 cal ka BP in central China, which was, in turn, probably connected to the rapid 9.2 ka climate event co-developing worldwide. In addition, based on the synthesis of our peat records and the other Holocene hydrological records from Asian summer monsoon (ASM) region, we further found that the 9.2 ka event probably constituted the strongest abrupt collapse of the Asian monsoon system during the full Holocene interval. The correlations between ASM and the atmospheric 14C production rate, the North Atlantic drift ice records and Greenland temperature indicated that the weakened ASM event at around 9.2 cal ka BP could be interpreted by the co-influence of external and internal factors, related to the changes of the solar activity and the Atlantic Meridional Overturning Circulation (AMOC).

  13. Microbial degradation of a metal organic biocide in soils; Mikrobieller Abbau eines im Holzschutz verwendeten metallorganischen Biozids im Boden

    Energy Technology Data Exchange (ETDEWEB)

    Jakobs, Desiree

    2010-06-17

    The soil microbial community is able to degrade wood and variety of chemical wood-preservatives (WP) to generate energy by producing CO{sub 2} and as nutrition source to establish biomass. This work is focused on the characterisation of the microbial degradation of metal-organic WP including Copper-HDO (Cu-HDO) as biocide via {sup 13}C tracer experiments. Investigations with sterilized and non-sterilized soul incubated with Cu-HDO demonstrated that degradation of Cu-HDO was accelerated by the presence of the soil microbial community. Leaching of treated wood into the surrounding soil is characterized by low Cu-HDO concentrations (5 {mu}g - 20 {mu}g). Measurements of such biocide-concentrations by HPLC over time showed that Cu-HDO was degraded within a few days of soil incubation. Cu-HDO solely was degraded faster in soil compared to Cu-HDO as part of a WP. Presence of Cu-HDO significantly decreased the overall soil respiration compared to samples without Cu-HDO. Detailed information of the microbial metabolic pathways was achieved by comparison of {sup 12}C and {sup 13}C enriched Cu-HDO experiments and thereafter SIP-PLFA analysis. Monitoring of the {delta}{sup 13}C in PLFAs revealed that the carbon derived from the biocide was integrated nearly exclusively into the abundant PLFAs affiliated to gram negative bacteria. PLFAs indicative for fungi and other eukaryotic organism could be found only in low relative abundances and without {delta}{sup 13}C enrichment. This result suggests that eukaryotes were not involved in utilization of Copper-HADO based carbon. To characterise the impact of the co-biocide HDO on the microbial community the composition of the microbial community present at the surface of Copper-HDO, Copper-Amine treated specimens as well as of untreated specimens in soil contact was investigated. The bacterial community structure was characterized by the T-RFLP fingerprinting technique whereas the eukaryotic community structure was analyzed by the SSCP

  14. Negotiating action

    Science.gov (United States)

    2017-12-01

    After years of working towards a climate accord, the Paris Agreement of 2015 marked the shift from negotiating to reach consensus on climate action to implementation of such action. The challenge now is to ensure transparency in the processes and identify the details of what is required.

  15. Enforcement actions: Significant actions resolved

    International Nuclear Information System (INIS)

    1994-03-01

    This compilation summarizes significant enforcement actions that have been resolved during one quarterly period (October - December 1993) and includes copies of letters, Notices, and Orders sent by the Nuclear Regulatory Commission to licensees with respect to these enforcement actions. It is anticipated that the information in this publication will be widely disseminated to managers and employees engaged in activities licensed by the NRC, so that actions can be taken to improve safety by avoiding future violations similar to those described in this publication

  16. Enforcement actions: Significant actions resolved

    International Nuclear Information System (INIS)

    1992-11-01

    This compilation summarizes significant enforcement actions that have been resolved during one quarterly period (July - September 1992) and includes copies of letters, Notices, and Orders sent by the Nuclear Regulatory Commission to licensees with respect to these enforcement actions. It is anticipated that the information in this publication will be widely disseminated to managers and employees engaged in activities licensed by the NRC, so that actions can be taken to improve safety by avoiding future violations similar to those described in this publication

  17. Enforcement actions: Significant actions resolved

    International Nuclear Information System (INIS)

    1990-05-01

    This compilation summarizes significant enforcement actions that have been resolved during one quarterly period (January--March 1990) and includes copies of letters, Notices, and Orders sent by the Nuclear Regulatory Commission to licensees with respect to these enforcement actions. Also included are a number of enforcement actions that had been previously resolved but not published in this NUREG. It is anticipated that the information in this publication will be widely disseminated to managers and employees engaged in activities licensed by the NRC, so that actions can be taken to improve safety by avoiding future violations similar to those described in this publication

  18. Enforcement actions: Significant actions resolved

    International Nuclear Information System (INIS)

    1989-06-01

    This compilation summarizes significant enforcement actions that have been resolved during one quarterly period (January--March 1989) and includes copies of letters, Notices, and Orders sent by the Nuclear Regulatory Commission to licensees with respect to these enforcement actions. Also included are a number of enforcement actions that had been previously resolved but not published in this NUREG. It is anticipated that the information in this publication will be widely disseminated to managers and employees engaged in activities licensed by the NRC, so that actions can be taken to improve safety by avoiding future violations similar to those described in this publication

  19. Double positivity for HPV-DNA/p16ink4a is the biomarker with strongest diagnostic accuracy and prognostic value for human papillomavirus related oropharyngeal cancer patients.

    Science.gov (United States)

    Mena, Marisa; Taberna, Miren; Tous, Sara; Marquez, Sandra; Clavero, Omar; Quiros, Beatriz; Lloveras, Belen; Alejo, Maria; Leon, Xavier; Quer, Miquel; Bagué, Silvia; Mesia, Ricard; Nogués, Julio; Gomà, Montserrat; Aguila, Anton; Bonfill, Teresa; Blazquez, Carmen; Guix, Marta; Hijano, Rafael; Torres, Montserrat; Holzinger, Dana; Pawlita, Michael; Pavon, Miguel Angel; Bravo, Ignacio G; de Sanjosé, Silvia; Bosch, Francesc Xavier; Alemany, Laia

    2018-03-01

    The etiologic role of human papillomaviruses (HPV) in oropharyngeal cancer (OPC) is well established. Nevertheless, information on survival differences by anatomic sub-site or treatment remains scarce, and it is still unclear the HPV-relatedness definition with best diagnostic accuracy and prognostic value. We conducted a retrospective cohort study of all patients diagnosed with a primary OPC in four Catalonian hospitals from 1990 to 2013. Formalin-fixed, paraffin-embedded cancer tissues were subjected to histopathological evaluation, DNA quality control, HPV-DNA detection, and p16 INK4a /pRb/p53/Cyclin-D1 immunohistochemistry. HPV-DNA positive and a random sample of HPV-DNA negative cases were subjected to HPV-E6*I mRNA detection. Demographic, tobacco/alcohol use, clinical and follow-up data were collected. Multivariate models were used to evaluate factors associated with HPV positivity as defined by four different HPV-relatedness definitions. Proportional-hazards models were used to compare the risk of death and recurrence among HPV-related and non-related OPC. 788 patients yielded a valid HPV-DNA result. The percentage of positive cases was 10.9%, 10.2%, 8.5% and 7.4% for p16 INK4a , HPV-DNA, HPV-DNA/HPV-E6*I mRNA, and HPV-DNA/p16 INK4a , respectively. Being non-smoker or non-drinker was consistently associated across HPV-relatedness definitions with HPV positivity. A suggestion of survival differences between anatomic sub-sites and treatments was observed. Double positivity for HPV-DNA/p16 INK4a showed strongest diagnostic accuracy and prognostic value. Double positivity for HPV-DNA/p16 INK4a , a test that can be easily implemented in the clinical practice, has optimal diagnostic accuracy and prognostic value. Our results have strong clinical implications for patients' classification and handling and also suggest that not all the HPV-related OPC behave similarly. Copyright © 2018 Elsevier Ltd. All rights reserved.

  20. Evaluation of biocide efficacy on microbiological induced corrosion of pipes and equipment from the 'process water system' of Embalse nuclear power plant (CNE)

    International Nuclear Information System (INIS)

    Forte Giacobone, A F; Burkart, A L; Pizarro, R; Rodriguez S; Belloni, M; Croatto, F; Ferrari, F; Herrera, C; Mendizabal, M; Montes, J; Rodriguez Aliciardi, M; Saucedo, R; Ovando, L

    2012-01-01

    In order to improve water quality, and mitigate recurrent bio corrosion phenomena affecting the components of the Process Water System of the CNE, a combined water treatment adding a commercial biocide product, based on bromide, to the currently injected chlorine was proposed. The aim of this study was to evaluate the effect of the added biocide on the kinetics of biofilm formation and growth, which is the precursor process to microbiological corrosion, and on the corrosion rates of carbon steel of pipes, heat exchanger shells and other system devices. For this purpose, a test bench was designed and built, reproducing the flow conditions at certain parts of the system. This facility was installed in the filtration shed of the Water Plant of the CNE. The test bench consisted of two parallel chambers, I and II, each in turn divided into a section for determining biofilm growth and corrosion rates of carbon steel coupons and another one to measure the kinetics of biofilm growth on stainless steel coupons. Both chambers received lake water chlorinated for 15 minutes each day. The chamber II received also the biocide. The corrosion rate in carbon steel coupons was evaluated by weight loss and Linear Polarization Resistance (LPR) measurements. The kinetics of biofilm growth on carbon steel coupons was measured using disruptive methods followed by quantification of the protein and carbohydrate content as an estimation of total biomase. The following bacterial groups were quantified through the dilution-extinction method: total aerobic bacteria, acid-producing bacteria, total anaerobic bacteria, sulfate reducing bacteria and bacteria precipitating iron and manganese. On the stainless steel coupons, the percent of coverage was evaluated by epi fluorescence microscopy. The corrosion rate results obtained both by weight loss as by LPR, showed no significant differences between both chambers, with and without biocide. Regarding the kinetics of biofilm growth on carbon steel

  1. Enforcement actions: Significant actions resolved

    International Nuclear Information System (INIS)

    1993-09-01

    This compilation summarizes significant enforcement actions that have been resolved during one quarterly period (April--June 1993) and includes copies of letters, Notices, and Orders sent by the Nuclear Regulatory Commission to licensees with respect to these enforcement actions. It is anticipated that the information in this publication will be widely disseminated to managers and employees engaged in activities licensed by the NRC, so that actions can be taken to improve safety by avoiding future violations similar to those described in this publication

  2. Enforcement actions: Significant actions resolved

    International Nuclear Information System (INIS)

    1991-05-01

    This compilation summarizes significant enforcement actions that have been resolved during one quarterly period (January--March 1991) and includes copies of letters, Notices, and Orders sent by the Nuclear Regulatory Commission to licensees with respect to these enforcement actions. It is anticipated that the information in this publication will be widely disseminated to managers and employees engaged in activities licensed by the NRC, so that actions can be taken to improve safety by avoiding future violations similar to those described in this publication

  3. Enforcement actions: Significant actions resolved

    International Nuclear Information System (INIS)

    1991-02-01

    This compilation summarizes significant enforcement actions that have been resolved during one quarterly period (October--December 1990) and includes copies of letters, Notices, and Orders sent by the Nuclear Regulatory Commission to licensees with respect to these enforcement actions. It is anticipated that the information in this publication will be widely disseminated to managers and employees engaged in activities licensed by the NRC, so that actions can be taken to improve safety by avoiding future violations similar to those described in this publication

  4. Enforcement actions: Significant actions resolved

    International Nuclear Information System (INIS)

    1990-03-01

    This compilation summarizes significant enforcement actions that have been resolved during one quarterly period (October--December 1989) and includes copies of letters, Notices, and Orders sent by the Nuclear Regulatory Commission to licensees with respect to these enforcement actions. It is anticipated that the information in this publication will be widely disseminated to managers and employees engaged in activities licensed by the NRC, so that actions can be taken to improve safety by avoiding future violations similar to those described in this publication

  5. Enforcement actions: Significant actions resolved

    International Nuclear Information System (INIS)

    1990-11-01

    This compilation summarizes significant enforcement actions that have been resolved during one quarterly period (July--September 1990) and includes copies of letters, notices, and orders sent by the Nuclear Regulatory Commission to licensees with respect to these enforcement actions. It is anticipated that the information in this publication will be widely disseminated to managers and employees engaged in activities licensed by the NRC, so that actions can be taken to improve safety by avoiding future violations similar to those described in this publication

  6. Enforcement actions: Significant actions resolved

    International Nuclear Information System (INIS)

    1992-08-01

    This compilation summarizes significant enforcement actions that have been resolved during one quarterly period (April--June 1992) and includes copies of letters, Notices, and Orders sent by the Nuclear Regulatory Commission to licensees with respect to these enforcement actions. It is anticipated that the information in this publication will be widely disseminated to managers and employees engaged in activities licensed by the NRC, so that actions can be taken to improve safety by avoiding future violations similar to those described in this publication

  7. Enforcement actions: Significant actions resolved

    International Nuclear Information System (INIS)

    1990-09-01

    This compilation summarizes significant enforcement actions that have been resolved during one quarterly period (April--June 1990) and includes copies of letters, notices, and orders sent by the Nuclear Regulatory Commission to licensees with respect to these enforcement actions. It is anticipated that the information in this publication will be widely disseminated to managers and employees engaged in activities licensed by the NRC, so that actions can be taken to improve safety by avoiding future violations similar to those described in this publication

  8. Enforcement actions: Significant actions resolved

    International Nuclear Information System (INIS)

    1993-06-01

    This compilation summarizes significant enforcement actions that have been resolved during one quarterly period (January--March 1993) and includes copies of letters, Notices, and Orders sent by the Nuclear Regulatory Commission to licensees with respect to these enforcement actions. It is anticipated that the information in this publication will be widely disseminated to managers and employees engaged in activities licensed by the NRC, so that actions can be taken to improve safety by avoiding future violations similar to those described in this publication

  9. Enforcement actions: Significant actions resolved

    International Nuclear Information System (INIS)

    1992-05-01

    This compilation summarizes significant enforcement actions that have been resolved during one quarterly period (January--March 1992) and includes copies of letters, Notices, and Orders sent by the Nuclear Regulatory Commission to licensees with respect to these enforcement actions. It is anticipated that the information in this publication will be widely disseminated to managers and employees engaged in activities licensed by the NRC, so that actions can be taken to improve safety by avoiding future violations similar to those described in this publication

  10. Enforcement actions: Significant actions resolved

    International Nuclear Information System (INIS)

    1993-12-01

    This compilation summarizes significant enforcement actions that have been resolved during one quarterly period (July--September 1993) and includes copies of letters, Notices, and Orders sent by the Nuclear Regulatory Commission to licensees with respect to these enforcement actions. It is anticipated that the information in this publication will be widely disseminated to managers and employees engaged in activities licensed by the NRC, so that actions can be taken to improve safety by avoiding future violations similar to those described in this publication

  11. Enforcement actions: Significant actions resolved

    International Nuclear Information System (INIS)

    1993-03-01

    This compilation summarizes significant enforcement actions that have been resolved during one quarterly period (October--December 1992) and includes copies of letters, Notices, and Orders sent by the Nuclear Regulatory Commission to licensees with respect to these enforcement actions. It is anticipated that the information in this publication will be widely disseminated to managers and employees engaged in activities licensed by the NRC, so that actions can be taken to improve safety by avoiding future violations similar to those described in this publication

  12. Enforcement actions: Significant actions resolved

    International Nuclear Information System (INIS)

    1991-07-01

    This compilation summarizes significant enforcement actions that have been resolved during one quarterly period (April-June 1991) and includes copies of letters, Notices, and Orders sent by the Nuclear Regulatory Commission to licensees with respect to these enforcement actions. It is anticipated that the information in this publication will be widely disseminated to managers and employees engaged in activities licensed by the NRC, so that actions can be taken to improve safety by avoiding future violations similar to those described in this publication

  13. Enforcement actions: Significant actions resolved

    International Nuclear Information System (INIS)

    1991-11-01

    This compilation summarizes significant enforcement actions that have been resolved during one quarterly period (July--September 1991) and includes copies of letters, Notices, and Orders sent by the Nuclear Regulatory Commission to licensees with respect to these enforcement actions. It is anticipated that the information in this publication will be widely disseminated to managers and employees engaged in activities licensed by the NRC, so that actions can be taken to improve safety by avoiding future violations similar to those described in this publication

  14. Enforcement actions: Significant actions resolved

    International Nuclear Information System (INIS)

    1992-03-01

    This compilation summarizes significant enforcement actions that have been resolved during one quarterly period (October--December 1991) and includes copies of letters, Notices, and Orders sent by the Nuclear Regulatory Commission to licensees with respect to these enforcement actions. It is anticipated that the information in this publication will be widely disseminated to managers and employees engaged in activities licensed by the NRC, so that actions can be taken to improve safety by avoiding future violations similar to those described in this publication

  15. Enforcement actions: Significant actions resolved

    International Nuclear Information System (INIS)

    1989-12-01

    This compilation summarizes significant enforcement actions that have been resolved during one quarterly period (July--September 1989) and includes copies of letters, Notices, and Orders sent by the Nuclear Regulatory Commission to licensees with respect to these enforcement actions. It is anticipated that the information in this publication will be widely disseminated to managers and employees engaged in activities licensed by the NRC, so that actions can be taken to improve safety by avoiding future violations similar to those described in this publication

  16. Organotins and new antifouling biocides in water and sediments from three Korean Special Management Sea Areas following ten years of tributyltin regulation: Contamination profiles and risk assessment.

    Science.gov (United States)

    Lam, Nguyen Hoang; Jeong, Hui-Ho; Kang, Su-Dong; Kim, Dae-Jin; Ju, Mi-Jo; Horiguchi, Toshihiro; Cho, Hyeon-Seo

    2017-08-15

    A simultaneous monitoring study on organotins (butyltins and phenyltins) and most frequently used alternative antifouling biocides (Irgarol 1051, Diuron, Sea-Nine 211 and M1) in water and sediments (n=44) collected from three Special Management Sea Areas operated by Korean government. The lower concentration of butyltins (BTs) than that of new antifouling biocides (NEW) was found in water but the significant greater concentration of BTs than that of NEW was still found in sediments. The tributyltin (TBT) levels in water exceeded the chronic criterion to protect seawater aquatic life at several sites. Even ten years after the ban of the use of TBT-based antifouling paint, the concentrations of TBT, Diuron and Irgarol 1051 in sediments from shipyards exceeded global sediment quality guidelines and potentially poses adverse risks on marine organisms and extremely high concentration of TBT up to 2304ng/g was found for a sediment collected at a shipyard. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Antifouling booster biocide extraction from marine sediments: a fast and simple method based on vortex-assisted matrix solid-phase extraction.

    Science.gov (United States)

    Caldas, Sergiane Souza; Soares, Bruno Meira; Abreu, Fiamma; Castro, Ítalo Braga; Fillmann, Gilberto; Primel, Ednei Gilberto

    2018-03-01

    This paper reports the development of an analytical method employing vortex-assisted matrix solid-phase dispersion (MSPD) for the extraction of diuron, Irgarol 1051, TCMTB (2-thiocyanomethylthiobenzothiazole), DCOIT (4,5-dichloro-2-n-octyl-3-(2H)-isothiazolin-3-one), and dichlofluanid from sediment samples. Separation and determination were performed by liquid chromatography tandem-mass spectrometry. Important MSPD parameters, such as sample mass, mass of C18, and type and volume of extraction solvent, were investigated by response surface methodology. Quantitative recoveries were obtained with 2.0 g of sediment sample, 0.25 g of C18 as the solid support, and 10 mL of methanol as the extraction solvent. The MSPD method was suitable for the extraction and determination of antifouling biocides in sediment samples, with recoveries between 61 and 103% and a relative standard deviation lower than 19%. Limits of quantification between 0.5 and 5 ng g -1 were obtained. Vortex-assisted MPSD was shown to be fast and easy to use, with the advantages of low cost and reduced solvent consumption compared to the commonly employed techniques for the extraction of booster biocides from sediment samples. Finally, the developed method was applied to real samples. Results revealed that the developed extraction method is effective and simple, thus allowing the determination of biocides in sediment samples.

  18. Evaluation of bactericidal and anti-biofilm properties of a novel surface-active organosilane biocide against healthcare associated pathogens and Pseudomonas aeruginosa biolfilm.

    Directory of Open Access Journals (Sweden)

    Jason Murray

    Full Text Available Healthcare acquired infections (HAI pose a great threat in hospital settings and environmental contamination can be attributed to the spread of these. De-contamination and, significantly, prevention of re-contamination of the environment could help in preventing/reducing this threat. Goldshield (GS5 is a novel organosilane biocide marketed as a single application product with residual biocidal activity. We tested the hypothesis that GS5 could provide longer-term residual antimicrobial activity than existing disinfectants once applied to surfaces. Thus, the residual bactericidal properties of GS5, Actichlor and Distel against repeated challenge with Staphylococcus aureus ATCC43300 were tested, and showed that GS5 alone exhibited longer-term bactericidal activity for up to 6 days on 316I stainless steel surfaces. Having established efficacy against S. aureus, we tested GS5 against common healthcare acquired pathogens, and demonstrated that, on average, a 1 log10 bactericidal effect was exhibited by GS5 treated surfaces, although biocidal activity varied depending upon the surface type and the species of bacteria. The ability of GS5 to prevent Pseudomonas aeruginosa biofilm formation was measured in standard microtitre plate assays, where it had no significant effect on either biofilm formation or development. Taken together the data suggests that GS5 treatment of surfaces may be a useful means to reducing bacterial contamination in the context of infection control practices.

  19. Optical emission spectroscopy for quantification of ultraviolet radiations and biocide active species in microwave argon plasma jet at atmospheric pressure

    Energy Technology Data Exchange (ETDEWEB)

    Wattieaux, G., E-mail: gaetan.wattieaux@laplace.univ-tlse.fr; Yousfi, M.; Merbahi, N.

    2013-11-01

    This work deals with absorption and mainly emission spectrometry of a microwave induced surfatron plasma jet launched in ambient air and using an Argon flow carrier gas. The Ar flow rate varies between 1 and 3 L/min and the microwave power between 40 and 60 W. The analysis of the various spectra has led to the determination of the ozone and atomic oxygen concentrations, ultraviolet (UV) irradiance separating UVA, UVB and UVC, gas temperature, plasma electron density and excitation temperature. Most of these diagnostics are spatially resolved along the plasma jet axis. It is shown more particularly that rotational temperature obtained from OH(A-X) spectra ranges between 800 K to 1000 K while the apparent temperature of the plasma jet remains lower than about 325 K which is compatible with biocide treatment without significant thermal effect. The electron density reaches 1.2 × 10{sup 14} cm{sup −3}, the excitation temperature is about 4000 K, the UVC radiation represents only 5% of the UV radiations emitted by the device, the ozone concentration is found to reach 88 ± 27 ppm in the downstream part of the plasma jet at a distance of 30 mm away from the quartz tube outlet of the surfatron and the atomic oxygen concentration lies between 10 and 80 ppm up to a distance of 20 mm away from the quartz tube outlet. Ozone is identified as the main germicidal active species produced by the device since its concentration is in accordance with bacteria inactivation durations usually reported using such plasma devices. Human health hazard assessment is carried out all along this study since simple solutions are reminded to respect safety standards for exposures to ozone and microwave leakage. In this study, an air extraction unit is used and a Faraday cage is set around the quartz tube of the surfatron and the plasma jet. These solutions should be adopted by users of microwave induced plasma in open air conditions because according to the literature, this is not often the

  20. Optical emission spectroscopy for quantification of ultraviolet radiations and biocide active species in microwave argon plasma jet at atmospheric pressure

    International Nuclear Information System (INIS)

    Wattieaux, G.; Yousfi, M.; Merbahi, N.

    2013-01-01

    This work deals with absorption and mainly emission spectrometry of a microwave induced surfatron plasma jet launched in ambient air and using an Argon flow carrier gas. The Ar flow rate varies between 1 and 3 L/min and the microwave power between 40 and 60 W. The analysis of the various spectra has led to the determination of the ozone and atomic oxygen concentrations, ultraviolet (UV) irradiance separating UVA, UVB and UVC, gas temperature, plasma electron density and excitation temperature. Most of these diagnostics are spatially resolved along the plasma jet axis. It is shown more particularly that rotational temperature obtained from OH(A-X) spectra ranges between 800 K to 1000 K while the apparent temperature of the plasma jet remains lower than about 325 K which is compatible with biocide treatment without significant thermal effect. The electron density reaches 1.2 × 10 14 cm −3 , the excitation temperature is about 4000 K, the UVC radiation represents only 5% of the UV radiations emitted by the device, the ozone concentration is found to reach 88 ± 27 ppm in the downstream part of the plasma jet at a distance of 30 mm away from the quartz tube outlet of the surfatron and the atomic oxygen concentration lies between 10 and 80 ppm up to a distance of 20 mm away from the quartz tube outlet. Ozone is identified as the main germicidal active species produced by the device since its concentration is in accordance with bacteria inactivation durations usually reported using such plasma devices. Human health hazard assessment is carried out all along this study since simple solutions are reminded to respect safety standards for exposures to ozone and microwave leakage. In this study, an air extraction unit is used and a Faraday cage is set around the quartz tube of the surfatron and the plasma jet. These solutions should be adopted by users of microwave induced plasma in open air conditions because according to the literature, this is not often the case

  1. Action Refinement

    NARCIS (Netherlands)

    Gorrieri, R.; Rensink, Arend; Bergstra, J.A.; Ponse, A.; Smolka, S.A.

    2001-01-01

    In this chapter, we give a comprehensive overview of the research results in the field of action refinement during the past 12 years. The different approaches that have been followed are outlined in detail and contrasted to each other in a uniform framework. We use two running examples to discuss

  2. Studies on the biocidal and cell membrane disruption potentials of stem bark extracts of Afzelia africana (Smith

    Directory of Open Access Journals (Sweden)

    DAVID A AKINPELU

    2009-01-01

    Full Text Available We had recently reported antibacterial activity in the crude extract of the stem bark of Afzelia africana (Akinpelu et al., 2008. In this study, we assessed the biocidal and cell membrane disruption potentials of fractions obtained from the crude extract of the plant. The aqueous (AQ and butanol (BL fractions exhibited appreciable antibacterial activities against the test bacteria. The minimum inhibitory concentrations of the AQ and BL fractions ranged between 0.313 and 2.5 mg/ml, while their minimum bactericidal concentrations varied between 0.625 and 5.0 mg/ml. Also, the AQ fraction killed about 95.8% of E. coli cells within 105 min at a concentration of 5 mg/ml, while about 99.1% of Bacillus pumilus cells were killed by this fraction at the same concentration and exposure time. A similar trend was observed for the BL fraction. At a concentration of 5 mg/ml, the butanol fraction leaked 9.8 μg/ml of proteins from E. coli cells within 3 h, while the aqueous fraction leaked 6.5 μg/ml of proteins from the same organisms at the same concentration and exposure time. We propose that the stem bark of Afzelia africana is a potential source of bioactive compounds of importance to the pharmaceutical industry.

  3. Analysis of isothiazolinone biocides in paper for food packaging by ultra-high-performance liquid chromatography-tandem mass spectrometry.

    Science.gov (United States)

    Lin, Q-B; Wang, T-J; Song, H; Li, B

    2010-12-01

    A novel and simple method to detect isothiazolinone-type biocides (2-methyl-3-isothiazolinone (MI), 5-chloro-2-methyl-3-isothiazolinone (CMI), 1,2-benzisothiazolinone (BIT) and 2-octyl-3-isothiazolinone (OIT)) in paper used for food packaging by ultrasonic extraction coupled with UPLC-MS/MS was developed. Parameters affecting process efficiency such as extraction solvents, UPLC mobile phase, gradient elution procedure and MS/MS conditions were studied to optimise the operating conditions. Using the optimised gradient elution procedure, the retention time was less than 6 min. The limits of detection (LODs) were found to be between 0.001 and 0.010 mg kg⁻¹, which was validated using actual concentrations. After diluting the standard solution with a blank matrix, the linear calibration curve ranges were 0.002-1.000 mg kg⁻¹ for BIT and OIT, 0.005-1.000 mg kg⁻¹ for MI, and 0.020-1.000 mg kg⁻¹ for CMI, with correlation coefficients higher than 0.9985 (n = 6). A good level of precision with a mean recovery greater than 81.3% and a relative standard deviation (RSD) less than 6.2% were also obtained. A methodology has been proposed for the analysis of isothiazolinones in paper.

  4. Effect of diesel leakage in circulating cooling water system on preponderant bacteria diversity and bactericidal effect of biocides.

    Science.gov (United States)

    Zhong, Huiyun; Liu, Fang; Lu, Jinjin; Yang, Wei; Zhao, Chaocheng

    2015-01-01

    Petroleum products leakage results in adverse effect on the normal operation of a circulating cooling water system. However, relatively little research has been done to explore the effect of petroleum products leakage on circulating cooling water quality and biofilm preponderant bacteria diversity. Also, normal biocides application modes cannot fulfil the need for biofilm control. In this study, diesel oil was used as the experimental subject representing leaking petroleum products; the effect of diesel addition on biofilm preponderant bacteria diversity and the bactericidal effect of chlorine dioxide and tetradecyl dimethyl benzyl ammonium chloride (1427) was investigated. Bacterial community structures were examined by PCR-denaturing gradient gel electrophoresis and PCR cloning of 16S rDNA genes. Except for 100 mg/L diesel, increasing diesel concentration enhanced the biofilm detachment ratio compared with the control test. The microstructure of biofilm samples with 0, 300 and 900 mg/L diesel addition was observed. The species of preponderant bacteria in the biofilm sample with 300 mg/L diesel addition were more and the bacterial distribution was more uniform than those in the biofilm sample with 900 mg/L diesel addition. With ClO2 and 1427 addition, chemical oxygen demand increased, lipid phosphorus and bacterial count first decreased and then remained stable, and the bactericidal ratio first increased and then remained stable. Diesel addition variation has more obvious effect on ClO2 than 1427.

  5. Tire tread wear particles in ambient air--a previously unknown source of human exposure to the biocide 2-mercaptobenzothiazole.

    Science.gov (United States)

    Avagyan, Rozanna; Sadiktsis, Ioannis; Bergvall, Christoffer; Westerholm, Roger

    2014-10-01

    Urban particulate matter (PM), asphalt, and tire samples were investigated for their content of benzothiazole and benzothiazole derivates. The purpose of this study was to examine whether wear particles, i.e., tire tread wear or road surface wear, could contribute to atmospheric concentrations of benzothiazole derivatives. Airborne particulate matter (PM10) sampled at a busy street in Stockholm, Sweden, contained on average 17 pg/m(3) benzothiazole and 64 pg/m(3) 2-mercaptobenzothiazole, and the total suspended particulate-associated benzothiazole and 2-mercaptobenzothiazole concentrations were 199 and 591 pg/m(3), respectively. This indicates that tire tread wear may be a major source of these benzothiazoles to urban air PM in Stockholm. Furthermore, 2-mercaptobenzothiazole was determined in urban air particulates for the first time in this study, and its presence in inhalable PM10 implies that the human exposure to this biocide is underestimated. This calls for a revision of the risk assessments of 2-mercaptobenzothiazole exposure to humans which currently is limited to occupational exposure.

  6. Co-Selection of Resistance to Antibiotics, Biocides and Heavy Metals, and Its Relevance to Foodborne Pathogens

    Directory of Open Access Journals (Sweden)

    Andrew D. Wales

    2015-11-01

    Full Text Available Concerns have been raised in recent years regarding co-selection for antibiotic resistance among bacteria exposed to biocides used as disinfectants, antiseptics and preservatives, and to heavy metals (particularly copper and zinc used as growth promoters and therapeutic agents for some livestock species. There is indeed experimental and observational evidence that exposure to these non-antibiotic antimicrobial agents can induce or select for bacterial adaptations that result in decreased susceptibility to one or more antibiotics. This may occur via cellular mechanisms that are protective across multiple classes of antimicrobial agents or by selection of genetic determinants for resistance to non-antibiotic agents that are linked to genes for antibiotic resistance. There may also be relevant effects of these antimicrobial agents on bacterial community structure and via non-specific mechanisms such as mobilization of genetic elements or mutagenesis. Notably, some co-selective adaptations have adverse effects on fitness in the absence of a continued selective pressure. The present review examines the evidence for the significance of these phenomena, particularly in respect of bacterial zoonotic agents that commonly occur in livestock and that may be transmitted, directly or via the food chain, to human populations.

  7. Nickel(II) and palladium(II) triphenylphosphine complexes incorporating tridentate Schiff base ligands: Synthesis, characterization and biocidal activities

    Science.gov (United States)

    Shabbir, Muhammad; Akhter, Zareen; Ashraf, Ahmad Raza; Ismail, Hammad; Habib, Anum; Mirza, Bushra

    2017-12-01

    Nickel(II) and palladium(II) triphenylphosphine complexes incorporating tridentate Schiff bases have been prepared and characterized by elemental analysis as well as by spectroscopic techniques (FTIR & NMR). The synthesized compounds were assessed to check their potential biocidal activity by using different biological assays (brine shrimp cytotoxicity, antimicrobial, antioxidant, antitumor and drug-DNA interaction). Results of brine shrimp cytotoxicity assay showed that ligand molecules are more bioactive than metal complexes with LD50 as low as 12.4 μg/mL. The prominent antitumor activity was shown by nickel complexes while the palladium complexes exhibited moderate activity. The synthesized compounds have shown high propensity for DNA binding either through intercalation or groove binding which represents the mechanism of antitumor effect of these compounds. Additionally, ligand molecules and nickel metal complexes showed significant antioxidant activity with IC50 values as low as 3.1 μg/mL and 18.9 μg/mL respectively while palladium complexes exhibited moderate activity. Moreover, in antimicrobial assays H2L1, Ni(L1)PPh3 and H2L3 showed dual inhibition against bacterial and fungal strains while for the rest of the compounds varying degree of activity was recorded against different strains. Overall comparison of results suggests that the synthesized compounds can be promising candidate for drug formulation and development.

  8. Evaluation of eco toxicity, biocide effectiveness and corrosiveness of fluid for pipelines hydro testing; Avaliacao da ecotoxicidade, eficiencia biocida e da corrosividade de fluidos para teste hidroestatico de dutos

    Energy Technology Data Exchange (ETDEWEB)

    Andrade, Cynthia A.; Veiga, Leticia F.; Penna, Monica O.; Souza, Leonardo S. [PETROBRAS, Rio de Janeiro, RJ (Brazil); Nascimento, Juliana R.; Oliveira, Fabio F.; Amigo, Alexandre A.; Chaves, Claudia [Fundacao Gorceix, Ouro Preto, MG (Brazil)

    2005-07-01

    Before the installation of subsea pipelines for draining the oil and gas production, the line need to be submitted to hydrostatic tests. In these, the lines are flooded with sea water and chemicals and pressurized to check the leakage occurrence. By the end of the test, the fluid needs to be discharged in-situ. Based on the environmental restrictions, this study began, and the three most important aspects in relation to the environmental risks had been evaluated: the toxicity, the biocide efficiency and the fluids' corrosiveness. By the partial results, it was observed that the fluids which had presented the best results in all studied aspects were the ones that contained the biocide THPS, combined with U.V. and a quaternary salt. In relation to the corrosion, it could be established that the studied fluids do not present impacts in internal corrosion, since during the test, the pipes are totally flooded with the fluid, remaining stamped and all the internal air having been removed. An important aspect is: even with concentrations below of the recommended ones for biocides, in order to guarantee lower environmental risks, by making use of alternative techniques (U.V.) and efficient biocide products, it is also possible to reach success in terms of biocide's efficiency. A regular monitoring procedure of the fulfilling fluid's quality is essential. (author)

  9. Copper-polymer nanocomposites: An excellent and cost-effective biocide for use on antibacterial surfaces.

    Science.gov (United States)

    Tamayo, Laura; Azócar, Manuel; Kogan, Marcelo; Riveros, Ana; Páez, Maritza

    2016-12-01

    The development of polymer nanocomposites with antimicrobial properties has been a key factor for controlling or inhibiting the growth of microorganisms and preventing foodborne diseases and nosocomial infections. Commercially available antibacterial products based on silver-polymer are the most widely used despite the fact that copper is considerably less expensive. The incorporation of copper nanoparticles as antibacterial agents in polymeric matrices to generate copper-polymer nanocomposites have presented excellent results in inhibiting the growth of a broad spectrum of microorganisms. The potential applications in food packaging, medical devices, textiles and pharmaceuticals and water treatment have generated an increasing number of investigations on preparing copper based nanocomposites and alternative polymeric matrices, as potential hosts of nano-modifiers. This review presents a comprehensive compilation of previous published work on the subject, mainly related to the antimicrobial activity of copper polymer nanocomposites. Within all the phenomenology associated to antibacterial effects we highlight the possible mechanisms of action. We discuss the differences in the susceptibility of Gram negative and positive bacteria to the antibacterial activity of nanocomposites, and influencing factors. As well, the main applications of copper polymer-metal nanocomposites are described, considering their physical and chemical characteristics. Finally, some commercially available copper-polymer nanocomposites are described. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. Biocidal effects of Piper hispidinervum (Piperaceae) essential oil and synergism among its main components.

    Science.gov (United States)

    Andrés, M F; Rossa, G E; Cassel, E; Vargas, R M F; Santana, O; Díaz, C E; González-Coloma, A

    2017-11-01

    In this study we evaluated the effect of a pressure gradient (1-2 atm) in the extraction and composition of the essential oil (EO) of Piper hispidinervum by steam distillation. We also evaluated the insect antifeedant effects (Spodoptera littoralis, Leptinotarsa decemlineata, Myzus persicae and Rhopalosiphum padi) and nematicidal activity (Meloidogyne javanica) of the oils, their major components and their synergistic interactions. Safrole was the major component (78-81%) followed by terpinolene (5-9%). The EOs tested were effective insect antifeedants. Safrole, explained most of the insect antifeedant action of P. hispidinervum EOs. When safrole and terpinolene were tested in binary combinations, low ratios of safrole improved the antifeedant effects of terpinolene. P. hispidinervum EOs caused higher mortality of M. javanica juveniles than their major components. In binary combinations, low ratios of terpinolene increased the nematicidal effects of safrole. The EO treatment strongly suppressed nematode egg hatching and juvenile infectivity. P. hispidinervum EOs affected the germination of S. lycopersicum and L. sativa mostly at 24 h of treatment, being L. sativa the most sensitive. Safrole moderately affected germination and root growth of L. sativa, S. lycopersicum and L. perenne. Terpinolene only affected S. lycopersicum root growth. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Unimpeded permeation of water through biocidal graphene oxide sheets anchored on to 3D porous polyolefinic membranes

    Science.gov (United States)

    Mural, Prasanna Kumar S.; Jain, Shubham; Kumar, Sachin; Madras, Giridhar; Bose, Suryasarathi

    2016-04-01

    3D porous membranes were developed by etching one of the phases (here PEO, polyethylene oxide) from melt-mixed PE/PEO binary blends. Herein, we have systematically discussed the development of these membranes using X-ray micro-computed tomography. The 3D tomograms of the extruded strands and hot-pressed samples revealed a clear picture as to how the morphology develops and coarsens over a function of time during post-processing operations like compression molding. The coarsening of PE/PEO blends was traced using X-ray micro-computed tomography and scanning electron microscopy (SEM) of annealed blends at different times. It is now understood from X-ray micro-computed tomography that by the addition of a compatibilizer (here lightly maleated PE), a stable morphology can be visualized in 3D. In order to anchor biocidal graphene oxide sheets onto these 3D porous membranes, the PE membranes were chemically modified with acid/ethylene diamine treatment to anchor the GO sheets which were further confirmed by Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and surface Raman mapping. The transport properties through the membrane clearly reveal unimpeded permeation of water which suggests that anchoring GO on to the membranes does not clog the pores. Antibacterial studies through the direct contact of bacteria with GO anchored PE membranes resulted in 99% of bacterial inactivation. The possible bacterial inactivation through physical disruption of the bacterial cell wall and/or reactive oxygen species (ROS) is discussed herein. Thus this study opens new avenues in designing polyolefin based antibacterial 3D porous membranes for water purification.3D porous membranes were developed by etching one of the phases (here PEO, polyethylene oxide) from melt-mixed PE/PEO binary blends. Herein, we have systematically discussed the development of these membranes using X-ray micro-computed tomography. The 3D tomograms of the extruded strands and

  12. Polypropylene film with silver nanoparticles and nanoclay aiming to action biocidal; Filme de polipropileno com nanoargila e nanoparticulas de prata visando a acao biocida

    Energy Technology Data Exchange (ETDEWEB)

    Oliani, W.L.; Lima, L.F.C.P.; Lugao, A.B.; Parra, D.F., E-mail: washoliani@usp.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Fermino, D.M.; Diaz, F.R.V. [Universidade de Sao Paulo (USP), Sao Paulo, SP (Brazil). Departamento de Engenharia Metalurgica e de Materiais; Santos, P.M. dos [Universidade de Sao Paulo (USP), SP (Brazil)

    2014-07-01

    This paper presents an initial study of films made of polypropylene nanoclay and silver nanoparticles. The nanocomposite of polypropylene (iPP), commercial organoclay - montmorillonite (MMT), Cloisite 20A at concentrations of 1.0% and silver nanoparticles (AgNPs) at a concentration of 0.1% were prepared in a twin-screw-extruder, using polypropylene with maleic anhydride (PP-g-MA) as coupling agent. The properties of nanocomposites of PP/MMT/AgNPs are closely related to the dispersion of silver particles and the distribution of sheets of MMT in the polymer matrix, which define its efficiency in the case of the particles and their interaction clay/polymer matrix. However, this combination of MMT and AgNPs that are polar, with the polymer matrix nonpolar in the molten state, presents a challenge. The characterization of the film was performed by analysis of X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and reduction of colony forming unit (CFU %). The results indicate the formation of predominantly exfoliated microstructures and agglomeration of silver nanoparticles in the film. The effect of silver nanoparticles was evaluated against bacteria E.coli and S.aureus. (author)

  13. Occurrence and persistence of antifouling biocide Irgarol 1051 and its main metabolite in the coastal waters of Southern England

    International Nuclear Information System (INIS)

    Zhou, John L.

    2008-01-01

    The toxicity and persistence of antifouling booster biocides are of major concern. This study reports the occurrence of Irgarol 1051 and its degradation product M1, in coastal waters of Southern England, during 2004-2005. The highest concentrations of Irgarol 1051 were 89 ng/L in water and 45 ng/g dry weight in sediments, with an overall mean (n = 108) of 13 ng/L and 16 ng/g in water and sediments, respectively. As the degradation product of Irgarol 1051, M1 was less widespread, with the highest concentration of 30 ng/L in water and 14 ng/g in sediments, with an overall mean (n = 108) of 5 ng/L and 4 ng/g in water and sediments, respectively. Overall, the concentration of Irgarol 1051 and M1 decreased significantly during the sampling period and in comparison to earlier studies during 2000 to early 2004, indicating that control measures by restricting the use of Irgarol 1051 are effective in reducing its concentrations in coastal waters. The distribution of Irgarol 1051 between sediments and water was significantly related to sediment organic carbon content. In addition, significantly higher concentrations of Irgarol 1051 were detected in paint particles than in sediment. The rate of release of Irgarol 1051 from paint residues is very slow, with a half life of approximately 1 y. Two important findings are emerging, first the importance of organic rich sediments and paint residues as major sites of storage for Irgarol 1051, and secondly Irgarol 1051 may be classified as a persistent organic pollutant due to its long half life

  14. Comparing a microbial biocide and chlorine as zebra mussel control strategies in an Irish drinking water treatment plant

    Directory of Open Access Journals (Sweden)

    Sara Meehan

    2013-06-01

    Full Text Available A need exists for an environmentally friendly mussel control method to replace chlorine and other traditional control methods currentlyutilised in drinking water plants and other infested facilities. Zequanox® is a newly commercialised microbial biocide for zebra and quaggamussels comprised of killed Pseudomonas fluorescens CL145A cells. The objective of this study was to compare the efficacy of adevelopmental formulation of Zequanox (referred to as MBI 401 FDP and chlorine treatments on adult and juvenile zebra mussels byrunning a biobox trial in conjunction with chlorine treatments at an infested Irish drinking water treatment plant. Since 2009, the plantmanagement has used a residual chlorine concentration of 2 mg/L in autumn to control both adult zebra mussels and juvenile settlement intheir three concrete raw water chambers. Juvenile mussel settlement was monitored in three bioboxes as well as in three treatment chambersin the plant for three months prior to treatment. Adult mussels were seeded into the chambers and bioboxes four days before treatment. InOctober 2011, the bioboxes were treated with MBI 401 FDP at 200 mg active substance/L, while chlorine treatment took place in the waterchambers. The MBI 401 FDP treatment lasted only 8 hours while chlorine treatment lasted seven days. Juvenile numbers were reduced tozero in both the bioboxes and treated chambers within seven days. Adult mussel mortality reached 80% for both the chlorine and MBI 401FDP treatment; however, mortality was achieved faster in the chlorine treatment. These results provided important insights into zebra musselcontrol alternatives to chlorine and supported further development of the now commercial product, Zequanox.

  15. Action Learning: Avoiding Conflict or Enabling Action

    Science.gov (United States)

    Corley, Aileen; Thorne, Ann

    2006-01-01

    Action learning is based on the premise that action and learning are inextricably entwined and it is this potential, to enable action, which has contributed to the growth of action learning within education and management development programmes. However has this growth in action learning lead to an evolution or a dilution of Revan's classical…

  16. Analysis of the proposed EU regulation concerning biocide products and its opportunities for alternative approaches and a toxicology for the 21st century (t4 report).

    Science.gov (United States)

    Ferrario, Daniele; Rabbit, Richard R

    2012-01-01

    On June 12, 2009, the European Commission adopted a proposal for a Regulation concerning the placement on the market and use of biocidal products, which, when it enters into force on January 1, 2013, will repeal and replace Directive 98/8/EC. The main reason for the revision of the current Directive was to promote best practices for environmental and human health protection, along with implementation of current developments in safety testing in order to create safer biocides. Moreover, the proposed Regulation aims to take into consideration the newest legislation on chemicals. This article evaluates the proposed Regulation in comparison to Directive 98/8/EC. Although the new proposal requires the sharing of vertebrate animal test data, both for product authorization and for newly developed active substances, it misses - in contrast to REACH - the opportunity to recognize the accelerating development of alternative approaches to animal testing, most recently with new momentum provided by "Toxicity Testing for the 21st Century", and to support the evolution of toxicology towards a new approach to testing. The new methods promise not only to decrease animal pain and suffering, but also to provide faster results and better prediction for human risk assessment compared to traditional methods. Unfortunately, methods mandated for human risk assessment in the proposal are still mainly based on traditional animal study extrapolation. We put forward and discuss possible alternative strategies, such as in vitro testing, integrated testing strategies, toxicokinetics, "omics", systems biology, bioinformatics, and computational modeling, all of which could be more encouraged by the proposal. Current opportunities to improve our tools for biocide risk assessment are discussed, delineating advantages, limitations, and development needs. It is suggested to open the proposed Regulation to alternative approaches that are based on human biology more than on extrapolation from animals

  17. Potassium metabisulphite as a potential biocide against Dekkera bruxellensis in fuel ethanol fermentations.

    Science.gov (United States)

    Bassi, A P G; Paraluppi, A L; Reis, V R; Ceccato-Antonini, S R

    2015-03-01

    Dekkera bruxellensis is an important contaminant yeast of fuel ethanol fermentations in Brazil, whose system applies cell repitching between the fermentative cycles. This work evaluated the addition of potassium metabisulphite (PMB) on yeast growth and fermentative yields in pure and co-cultures of Saccharomyces cerevisiae and D. bruxellensis in two situations: addition to the acidic solution in which the cells are treated between the fermentative cycles or to the fermentation medium. In the range of 200-400 mg l(-1) , PMB was effective to control the growth of D. bruxellensis depending on the culture medium and strain. When added to the acidic solution (250 mg l(-1) ), a significant effect was observed in mixed cultures, because the inactivation of SO2 by S. cerevisiae most likely protected D. bruxellensis from being damaged by PMB. The physiological response of S. cerevisiae to the presence of PMB may explain the significant decrease in alcohol production. When added to the fermentation medium, PMB resulted in the control but not the death of D. bruxellensis, with less intensive effect on the fermentative efficiency. In co-culture with the addition of PMB, the fermentative efficiency was significantly lower than in the absence of PMB. This study is the first to evaluate the action of potassium metabisulphite to control the growth of Dekkera bruxellensis in the fermentation process for fuel alcohol production. As near as possible of industrial conditions, the study simulates the addition of that substance in different points in the fermentation process, verifying in which situation the effects over the starter yeast and alcohol yield are minimal and over D. bruxellensis are maximal. Co-culture fermentations were carried out in cell-recycled batch system. The feasibility of using this substance for this specific fermentation is discussed in light of the possible biological and chemical interactions. © 2014 The Society for Applied Microbiology.

  18. Inactivation of Bacillus anthracis Spores by a Combination of Biocides and Heating under High-Temperature Short-Time Pasteurization Conditions ▿

    Science.gov (United States)

    Xu, Sa; Labuza, Theodore P.; Diez-Gonzalez, Francisco

    2008-01-01

    The milk supply is considered a primary route for a bioterrorism attack with Bacillus anthracis spores because typical high-temperature short-time (HTST) pasteurization conditions cannot inactivate spores. In the event of intentional contamination, an effective method to inactivate the spores in milk under HTST processing conditions is needed. This study was undertaken to identify combinations and concentrations of biocides that can inactivate B. anthracis spores at temperatures in the HTST range in less than 1 min. Hydrogen peroxide (HP), sodium hypochlorite (SH), and peroxyacetic acid (PA) were evaluated for their efficacy in inactivating spores of strains 7702, ANR-1, and 9131 in milk at 72, 80, and 85°C using a sealed capillary tube technique. Strains ANR-1 and 9131 were more resistant to all of the biocide treatments than strain 7702. Addition of 1,260 ppm SH to milk reduced the number of viable spores of each strain by 6 log CFU/ml in less than 90 and 60 s at 72 and 80°C, respectively. After neutralization, 1,260 ppm SH reduced the time necessary to inactivate 6 log CFU/ml (TTI6-log) at 80°C to less than 20 s. Treatment of milk with 7,000 ppm HP resulted in a similar level of inactivation in 60 s. Combined treatment with 1,260 ppm SH and 1,800 ppm HP inactivated spores of all strains in less than 20 s at 80°C. Mixing 15 ppm PA with milk containing 1,260 ppm SH resulted in TTI6-log of 25 and 12 s at 72 and 80°C, respectively. TTI6-log of less than 20 s were also achieved at 80°C by using two combinations of biocides: 250 ppm SH, 700 ppm HP, and 150 ppm PA; and 420 ppm SH (pH 7), 1,100 ppm HP, and 15 ppm PA. These results indicated that different combinations of biocides could consistently result in 6-log reductions in the number of B. anthracis spores in less than 1 min at temperatures in the HTST range. This information could be useful for developing more effective thermal treatment strategies which could be used in HTST milk plants to process

  19. Inactivation of Bacillus anthracis spores by a combination of biocides and heating under high-temperature short-time pasteurization conditions.

    Science.gov (United States)

    Xu, Sa; Labuza, Theodore P; Diez-Gonzalez, Francisco

    2008-06-01

    The milk supply is considered a primary route for a bioterrorism attack with Bacillus anthracis spores because typical high-temperature short-time (HTST) pasteurization conditions cannot inactivate spores. In the event of intentional contamination, an effective method to inactivate the spores in milk under HTST processing conditions is needed. This study was undertaken to identify combinations and concentrations of biocides that can inactivate B. anthracis spores at temperatures in the HTST range in less than 1 min. Hydrogen peroxide (HP), sodium hypochlorite (SH), and peroxyacetic acid (PA) were evaluated for their efficacy in inactivating spores of strains 7702, ANR-1, and 9131 in milk at 72, 80, and 85 degrees C using a sealed capillary tube technique. Strains ANR-1 and 9131 were more resistant to all of the biocide treatments than strain 7702. Addition of 1,260 ppm SH to milk reduced the number of viable spores of each strain by 6 log CFU/ml in less than 90 and 60 s at 72 and 80 degrees C, respectively. After neutralization, 1,260 ppm SH reduced the time necessary to inactivate 6 log CFU/ml (TTI6-log) at 80 degrees C to less than 20 s. Treatment of milk with 7,000 ppm HP resulted in a similar level of inactivation in 60 s. Combined treatment with 1,260 ppm SH and 1,800 ppm HP inactivated spores of all strains in less than 20 s at 80 degrees C. Mixing 15 ppm PA with milk containing 1,260 ppm SH resulted in TTI6-log of 25 and 12 s at 72 and 80 degrees C, respectively. TTI6-log of less than 20 s were also achieved at 80 degrees C by using two combinations of biocides: 250 ppm SH, 700 ppm HP, and 150 ppm PA; and 420 ppm SH (pH 7), 1,100 ppm HP, and 15 ppm PA. These results indicated that different combinations of biocides could consistently result in 6-log reductions in the number of B. anthracis spores in less than 1 min at temperatures in the HTST range. This information could be useful for developing more effective thermal treatment strategies which could be

  20. Modelling inorganic and organic biocide leaching from CBA-amine (Copper–Boron–Azole) treated wood based on characterisation leaching tests

    Energy Technology Data Exchange (ETDEWEB)

    Lupsea, Maria [University of Toulouse, INSA, UPS, INP, LISBP, 135 Avenue de Rangueil, F–31077 Toulouse (France); INRA, UMR 792, F-31400 Toulouse (France); CNRS, UMR 5504, F-31400 Toulouse (France); Paris-Est University, CSTB — Scientific and Technical Centre for the Building Industry, DEE/Environment and Life Cycle Engineering Team, 24 Rue Joseph Fourier, F-38400 Saint Martin d' Hères (France); Tiruta-Barna, Ligia, E-mail: ligia.barna@insa-toulouse.fr [University of Toulouse, INSA, UPS, INP, LISBP, 135 Avenue de Rangueil, F–31077 Toulouse (France); INRA, UMR 792, F-31400 Toulouse (France); CNRS, UMR 5504, F-31400 Toulouse (France); Schiopu, Nicoleta [Paris-Est University, CSTB — Scientific and Technical Centre for the Building Industry, DEE/Environment and Life Cycle Engineering Team, 24 Rue Joseph Fourier, F-38400 Saint Martin d' Hères (France); Schoknecht, Ute [BAM — Federal Institute for Materials Research and Testing, Division 4.1, Unter den Eichen 87, 12205 Berlin (Germany)

    2013-09-01

    Numerical simulation of the leaching behaviour of treated wood is the most pertinent and less expensive method for the prediction of biocides' release in water. Few studies based on mechanistic leaching models have been carried out so far. In this work, a coupled chemistry-mass transport model is developed for simulating the leaching behaviour of inorganic (Cu, B) and organic (Tebuconazole) biocides from CBA-amine treated wood. The model is based on experimental investigations (lab-scale leaching tests coupled with chemical and structural analysis). It considers biocides' interactions with wood solid components and with extractives (literature confirmed reactions), as well as transport mechanisms (diffusion, convection) in different compartments. Simulation results helped at identifying the main fixation mechanisms, like (i) direct complexation of Cu by wood-phenolic and -carboxylic sites (and not via monoethanolamine; complex) on lignin and hemicellulose and strong dependence on extractives' nature, (ii) pH dependent binding of tebuconazole on polarized -OH moieties on wood. The role of monoethanolamine is to provide a pore-solution pH of about 7.5, when copper solubility is found to be weakest. The capability of the developed model to simulate the chemical and transport behaviour is the main result of this study. Moreover, it proved that characterization leaching tests (pH dependency and dynamic tests), combined with appropriate analytical methods are useful experimental tools. Due to its flexibility for representing and simulating various leaching conditions, chemical-transport model developed could be used to further simulate the leaching behaviour of CBA treated wood at larger scales. - Highlights: • Biocide and extractives leaching from ammonia-CBA treated wood were modelled. • The chemical-transport model identifies the main fixation/solubilisation mechanisms. • The model describes well the results of equilibrium and dynamic leaching

  1. A flow-through aqueous standard generation system for thin film microextraction investigations of UV filters and biocides partitioning to different environmental compartments

    International Nuclear Information System (INIS)

    Ahmadi, Fardin; Sparham, Chris; Pawliszyn, Janusz

    2017-01-01

    In this paper problems associated with preparation of aqueous standard of highly hydrophobic compounds such as partial precipitation, being lost on the surfaces, low solubility in water and limited sample volume for accurate determination of their distribution coefficients are addressed. The following work presents two approaches that utilize blade thin film microextraction (TFME) to investigate partitioning of UV filters and biocides to humic acid (dissolved organic carbon) and sediment. A steady-state concentration of target analytes in water was generated using a flow-through aqueous standard generation (ASG) system. Dialysis membranes, a polytetrafluoroethylene permeation tube, and a frit porous (0.5 μm) coated by epoxy glue were basic elements used for preparation of the ASG system. In the currently presented study, negligible depletion TFME using hydrophilic-lipophilic balance (HLB) and octadecyl silica-based (C18) sorbents was employed towards the attainment of free concentration values of target analytes in the studied matrices. Thin film geometry provided a large volume of extraction phase, which improved the sensitivity of the method towards highly matrix-bound analytes. Extractions were performed in the equilibrium regime so as to prevent matrix effects and with aims to reach maximum method sensitivity for all analytes under study. Partitioning of analytes on dissolved organic carbon (DOC) was investigated in ASG to facilitate large sample volume conditions. Binding percentages and DOC distribution coefficients (Log K DOC ) ranged from 20 to 98% and 3.71–6.72, respectively. Furthermore, sediment-water partition coefficients (K d ), organic-carbon normalized partition coefficients (Log K OC ), and DOC distribution coefficients (Log K DOC ) were investigated in slurry sediment, and ranged from 33 to 2860, 3.31–5.24 and 4.52–5.75 Lkg -1 , respectively. The obtained results demonstrated that investigations utilizing ASG and TFME can yield reliable

  2. Susceptibility of 169 USA300 methicillin-resistant Staphylococcus aureus isolates to two copper-based biocides, CuAL42 and CuWB50.

    Science.gov (United States)

    Luna, Vicki Ann; Hall, Tony J; King, Debbie S; Cannons, Andrew C

    2010-05-01

    To test the activity of two copper-based biocides, CuAL42 and CuWB50, and benzalkonium chloride against 169 isolates of methicillin-resistant Staphylococcus aureus (MRSA) pulsotype USA300, a virulent, multiply resistant, widespread clone in the USA. Tests including MIC, MBC and time-kill studies were performed multiple times. The MIC range, MIC(50) and MIC(90) (0.59-18.75, 4.69 and 4.69 ppm, respectively) and the MBC range, MBC(50) and MBC(90) (1.17-18.75, 4.69 and 9.38 ppm, respectively) for CuAL42 were identical with those obtained with CuWB50, except that the MBC range for CuWB50 was wider (0.59-37.5 ppm). In time-kill studies, a 6 log(10) reduction of cfu was achieved within 1 h (150 ppm) and 0.5 h (300 ppm) for CuAL42, and 1.5 h (150 ppm) and 0.75 h (300 ppm) for CuWB50. Both copper-based biocides can effectively kill USA300 MRSA and may facilitate the eradication of the organism from healthcare settings.

  3. The use of nanomaterials as an alternative to biocidal antifouling coatings and their environmental impact; Einsatz von Nanomaterialien als Alternative zu biozidhaltigen Antifouling-Anstrichen und deren Umweltauswirkungen

    Energy Technology Data Exchange (ETDEWEB)

    Watermann, B T; Daehne, D; Fuerle, C [LimnoMar - Labor fuer limnische/marine Forschung und vergleichende Pathologie, Hamburg (Germany)

    2010-07-15

    This study revealed that a variety of nanomaterials are already in use for antifouling paint systems. On the market for leisure boats 22 antifouling products and 3 under water coatings to reduce the friction could be identified (after an update in Mai 2010 only 14 products could be identified). These products are available on the German, the European and the global market. For all antifouling systems and underwater coatings on the market, the specification of the used nanomaterials was not specified e.g. in the Technical Data Sheets or Safety and Health Data Sheets. A clear labelling for the consumer would be helpful and necessary Actually, nanotechnology based antifouling systems on the leisure boat market and on the professional market cannot be regarded as alternatives to antifouling systems which are not using nanotechnology This is partly due to the lacking evidence of efficacy, the fact that some products contain biocides without declaring them, some of them are even not allowed to be used as biocides in antifouling paints (e.g. zinc oxide and silver) and due to the lack of specified nanomaterials which make a risk assessment or ecotoxicological evaluation impossible. It can be expected that the next generation of nanotechnology based antifouling systems will be much more sophisticated and effective, despite of the lack of scientific sound data on their environmental impact. (orig.)

  4. New priority substances of the European Water Framework Directive: biocides, pesticides and brominated flame retardants in the aquatic environment of Denmark.

    Science.gov (United States)

    Vorkamp, Katrin; Bossi, Rossana; Bester, Kai; Bollmann, Ulla E; Boutrup, Susanne

    2014-02-01

    The biocides cybutryn (Irgarol) and terbutryn, the herbicides aclonifen and bifenox, the insecticides cypermethrin and heptachlor/heptachlor epoxide and the brominated flame retardant hexabromocyclododecane (HBCD) are new priority substances of the Water Framework Directive of the European Union. In order to gain knowledge about their presence in the aquatic environment in an off-season situation with regard to pesticide and biocide applications, these substances were analysed in freshwater, seawater and fish samples from Denmark. Aclonifen, bifenox, cypermethrin and heptachlor were below the limits of detection (LODs) in all samples. However, the LODs for cypermethrin and heptachlor exceeded the annual average environmental quality standards (AA-EQSs). Cybutryn, terbutryn, heptachlor epoxide and HBCD were detected in the majority of samples, with detection frequencies of 100% for heptachlor epoxide and HBCD in water and 90% in fish. No concentration was above maximum allowable concentration (MAC)-EQS values, but AA-EQS values were exceeded for all four compounds by several samples, including 100% of the water samples with regard to heptachlor epoxide. Methodological issues remain for cypermethrin, and to a certain extent for heptachlor/heptachlor epoxide, for which water LODs were above AA-EQSs although a water volume of 12L was combined with very sensitive high resolution mass spectrometry. © 2013.

  5. In-Flight Water Quality Monitoring on the International Space Station (ISS): Measuring Biocide Concentrations with Colorimetric Solid Phase Extraction (CSPE)

    Science.gov (United States)

    Gazda, Daniel B.; Schultz, John R.; Siperko, Lorraine M.; Porter, Marc D.; Lipert, Robert J.; Flint, Stephanie M.; McCoy, J. Torin

    2011-01-01

    The colorimetric water quality monitoring kit (CWQMK) was delivered to the International Space Station (ISS) on STS-128/17A and was initially deployed in September 2009. The kit was flown as a station development test objective (SDTO) experiment to evaluate the acceptability of colorimetric solid phase extraction (CSPE) technology for routine water quality monitoring on the ISS. During the SDTO experiment, water samples from the U.S. water processor assembly (WPA), the U.S. potable water dispenser (PWD), and the Russian system for dispensing ground-supplied water (SVO-ZV) were collected and analyzed with the CWQMK. Samples from the U.S. segment of the ISS were analyzed for molecular iodine, which is the biocide added to water in the WPA. Samples from the SVOZV system were analyzed for ionic silver, the biocide used on the Russian segment of the ISS. In all, thirteen in-flight analysis sessions were completed as part of the SDTO experiment. This paper provides an overview of the experiment and reports the results obtained with the CWQMK. The forward plan for certifying the CWQMK as operational hardware and expanding the capabilities of the kit are also discussed.

  6. Quantitative comparison of the results obtained by the multiple-dose guinea pig maximization test and the non-radioactive murine local lymph-node assay for various biocides.

    Science.gov (United States)

    Yamano, Tetsuo; Shimizu, Mitsuru; Noda, Tsutomu

    2005-07-01

    We compared the results of the multiple-dose guinea pig maximization test (GPMT) and the non-radioactive murine local lymph-node assay (LLNA) for various biocides. Thirteen out of 17 positive biocides in the GPMT gave positive results in the LLNA. In the GPMT, the minimum first induction doses ranged over four orders (0.00005-0.5%), while elicitation-threshold doses, which were evaluated using an optimally sensitized group of animals in the multiple-dose studies, ranged over five orders (0.00006-2.8%). In the LLNA, minimum induction doses ranged over more than three orders (0.01-30%). With respect to 13 biocides that were positive in both the GPMT and the LLNA, results were quantitatively compared. When compared after conversion to corresponding area doses (microg/cm), the minimum doses required to elicit skin reaction in guinea pigs were always lower than that for induction in mice with all biocides. Correlation between minimum induction doses from the GPMT and the LLNA seemed poor (r=0.57), while that between minimum induction doses in the LLNA and elicitation-threshold doses in the GPMT was relatively good (r=0.73). The results suggest the possibility to estimate human elicitation-threshold doses, which are definitely lacking in the process of risk assessment for skin-sensitizers, from the data of the LLNA.

  7. Quantitative comparison of the results obtained by the multiple-dose guinea pig maximization test and the non-radioactive murine local lymph-node assay for various biocides

    International Nuclear Information System (INIS)

    Yamano, Tetsuo; Shimizu, Mitsuru; Noda, Tsutomu

    2005-01-01

    We compared the results of the multiple-dose guinea pig maximization test (GPMT) and the non-radioactive murine local lymph-node assay (LLNA) for various biocides. Thirteen out of 17 positive biocides in the GPMT gave positive results in the LLNA. In the GPMT, the minimum first induction doses ranged over four orders (0.00005-0.5%), while elicitation-threshold doses, which were evaluated using an optimally sensitized group of animals in the multiple-dose studies, ranged over five orders (0.00006-2.8%). In the LLNA, minimum induction doses ranged over more than three orders (0.01-30%). With respect to 13 biocides that were positive in both the GPMT and the LLNA, results were quantitatively compared. When compared after conversion to corresponding area doses (μg/cm), the minimum doses required to elicit skin reaction in guinea pigs were always lower than that for induction in mice with all biocides. Correlation between minimum induction doses from the GPMT and the LLNA seemed poor (r = 0.57), while that between minimum induction doses in the LLNA and elicitation-threshold doses in the GPMT was relatively good (r = 0.73). The results suggest the possibility to estimate human elicitation-threshold doses, which are definitely lacking in the process of risk assessment for skin-sensitizers, from the data of the LLNA

  8. Superb hydroxyl radical-mediated biocidal effect induced antibacterial activity of tuned ZnO/chitosan type II heterostructure under dark

    International Nuclear Information System (INIS)

    Podder, Soumik; Halder, Suman; Roychowdhury, Anirban; Das, Dipankar; Ghosh, Chandan Kr.

    2016-01-01

    Reactive oxygen species (ROS) is the most dominating factor for bacteria cell toxicity due to release of oxidative stress. Hydroxyl radical ("·OH) is a strong oxidizing ROS that has high impact on biocidal activity. This present paper highlights "·OH influenced antibacterial activity and biocidal propensity of tuned ZnO/chitosan (ZnO/CS) nanocomposite against Pseudomonas putida (P. putida) in the absence of light for the first time. For this purpose, the CS proportion was increased by 25 % (w/w) of ZnO during the preparation of ZnO/CS nanocomposite and a systematic study of different ROS like superoxide anion (O_2"·"−), hydrogen peroxide (H_2O_2) and "·OH production as well as their kinetics was carried out both under UV irradiation and in dark by UV–Vis spectroscopy using NBT dye, starch and iodine reaction and fluorescence spectroscopy using terephthalic acid. The decoration of ZnO nanoparticles (ZnO·NPs) with CS tuning was characterized by XRD and FTIR spectroscopy, revealing sustained crystallinity and surface coating of ZnO NP (size about ~24 nm) by CS molecule. The hybridization of ZnO nanoparticles with CS@50 wt% (w/w) resulted superior biocidal activity (81 %) within 3 h in dark mediated by optimum production of "·OH among all ROS. Here we have proposed the enhanced production of "·OH in ZnO/CS due to generation of holes by entrapment of electrons in acceptor level formed in nanocomposite for the first time, and the acceptor levels were probed by Positron annihilation lifetime spectroscopy. The increase in non-positronium (non-Ps) formation probability (I_2) in ZnO/CS nanocomposite confirmed the acceptor levels. This work also confirms surface defect-mediated ROS generation in dark, and zinc interstitials are proposed as active defect sites for generation of holes and "·OH for the first time and confirmed by steady-state room temperature photoluminescence spectroscopy. Finally, a plausible mechanism was hypothesized focusing on hole

  9. Investigations of the Effects of Biocide Dosing and Chemical Cleaning on the Organic Carbon Removal in an Integrated Ultrafiltration - Nanofiltration Desalination Pilot Plant

    KAUST Repository

    Khojah, Bayan A.

    2017-12-01

    Membrane desalination has become one of the most important desalination technologies used in the world. It provides high water quality for numerous applications and it demonstrates excellent desalination efficiency. One of the most troubling drawbacks of membrane desalination is membrane fouling. It decreases the performance of the membranes and increases the energy requirement. Two of the most important causes of fouling are microbes and organic matter. Hence, to maintain an optimized desalination performance, routine inspection of microbial and organic contents of water is crucial for desalination plants. In this study, water samples were obtained from different treatment points in an ultrafiltration (UF)/nanofiltration (NF) seawater desalination pilot plant. This was performed to better understand how the water quality changes along the desalination scheme. The effect of fouling control techniques, including Chemically Enhanced Backwash (CEB), Cleaning in Place (CIP), and the addition of a biocide (DBNPA) was studied. Different analytical tools were applied, including Bactiquant, Total Organic Carbon (TOC), Assimilable Organic Carbon (AOC), and Liquid Chromatography for Organic Carbon Detection (LC-OCD). Out results showed that UF did not decrease TOC but it was sufficient in removing up to 99.7% of bacteria. Nanofiltration, removed up to 95% of TOC. However, NF permeate had a high increase in AOC as compared to the raw seawater sample. The LC-OCD results suggested that this might be due to the increased low molecular weight neutrals which were the most common organic species in the NF permeate. The fouling control techniques showed various effects on the desalination efficiency. Daily CEB did not cause a reduction in TOC or bacteria but decreased AOC in the UF filtrate. The biocide addition resulted in an adequate membranes protection from fouling and it did not affect the investigated water parameters. When the dosing of biocide was stopped, the water quality

  10. Superb hydroxyl radical-mediated biocidal effect induced antibacterial activity of tuned ZnO/chitosan type II heterostructure under dark

    Science.gov (United States)

    Podder, Soumik; Halder, Suman; Roychowdhury, Anirban; Das, Dipankar; Ghosh, Chandan Kr.

    2016-10-01

    Reactive oxygen species (ROS) is the most dominating factor for bacteria cell toxicity due to release of oxidative stress. Hydroxyl radical (·OH) is a strong oxidizing ROS that has high impact on biocidal activity. This present paper highlights ·OH influenced antibacterial activity and biocidal propensity of tuned ZnO/chitosan (ZnO/CS) nanocomposite against Pseudomonas putida (P. putida) in the absence of light for the first time. For this purpose, the CS proportion was increased by 25 % (w/w) of ZnO during the preparation of ZnO/CS nanocomposite and a systematic study of different ROS like superoxide anion (O 2 ·- ), hydrogen peroxide (H2O2) and ·OH production as well as their kinetics was carried out both under UV irradiation and in dark by UV-Vis spectroscopy using NBT dye, starch and iodine reaction and fluorescence spectroscopy using terephthalic acid. The decoration of ZnO nanoparticles (ZnO·NPs) with CS tuning was characterized by XRD and FTIR spectroscopy, revealing sustained crystallinity and surface coating of ZnO NP (size about 24 nm) by CS molecule. The hybridization of ZnO nanoparticles with CS@50 wt% (w/w) resulted superior biocidal activity (81 %) within 3 h in dark mediated by optimum production of ·OH among all ROS. Here we have proposed the enhanced production of ·OH in ZnO/CS due to generation of holes by entrapment of electrons in acceptor level formed in nanocomposite for the first time, and the acceptor levels were probed by Positron annihilation lifetime spectroscopy. The increase in non-positronium (non-Ps) formation probability (I2) in ZnO/CS nanocomposite confirmed the acceptor levels. This work also confirms surface defect-mediated ROS generation in dark, and zinc interstitials are proposed as active defect sites for generation of holes and ·OH for the first time and confirmed by steady-state room temperature photoluminescence spectroscopy. Finally, a plausible mechanism was hypothesized focusing on hole generation in ZnO NP and

  11. Superb hydroxyl radical-mediated biocidal effect induced antibacterial activity of tuned ZnO/chitosan type II heterostructure under dark

    Energy Technology Data Exchange (ETDEWEB)

    Podder, Soumik [Jadavpur University, School of Materials Science and Nanotechnology (India); Halder, Suman [Jadavpur University, Department of Pharmaceutical Technology (India); Roychowdhury, Anirban; Das, Dipankar [Kolkata Centre, UGC-DAE Consortium for Scientific Research (India); Ghosh, Chandan Kr., E-mail: chandu-ju@yahoo.co.in [Jadavpur University, School of Materials Science and Nanotechnology (India)

    2016-10-15

    Reactive oxygen species (ROS) is the most dominating factor for bacteria cell toxicity due to release of oxidative stress. Hydroxyl radical ({sup ·}OH) is a strong oxidizing ROS that has high impact on biocidal activity. This present paper highlights {sup ·}OH influenced antibacterial activity and biocidal propensity of tuned ZnO/chitosan (ZnO/CS) nanocomposite against Pseudomonas putida (P. putida) in the absence of light for the first time. For this purpose, the CS proportion was increased by 25 % (w/w) of ZnO during the preparation of ZnO/CS nanocomposite and a systematic study of different ROS like superoxide anion (O{sub 2}{sup ·−}), hydrogen peroxide (H{sub 2}O{sub 2}) and {sup ·}OH production as well as their kinetics was carried out both under UV irradiation and in dark by UV–Vis spectroscopy using NBT dye, starch and iodine reaction and fluorescence spectroscopy using terephthalic acid. The decoration of ZnO nanoparticles (ZnO·NPs) with CS tuning was characterized by XRD and FTIR spectroscopy, revealing sustained crystallinity and surface coating of ZnO NP (size about ~24 nm) by CS molecule. The hybridization of ZnO nanoparticles with CS@50 wt% (w/w) resulted superior biocidal activity (81 %) within 3 h in dark mediated by optimum production of {sup ·}OH among all ROS. Here we have proposed the enhanced production of {sup ·}OH in ZnO/CS due to generation of holes by entrapment of electrons in acceptor level formed in nanocomposite for the first time, and the acceptor levels were probed by Positron annihilation lifetime spectroscopy. The increase in non-positronium (non-Ps) formation probability (I{sub 2}) in ZnO/CS nanocomposite confirmed the acceptor levels. This work also confirms surface defect-mediated ROS generation in dark, and zinc interstitials are proposed as active defect sites for generation of holes and {sup ·}OH for the first time and confirmed by steady-state room temperature photoluminescence spectroscopy. Finally, a

  12. DAPs: Deep Action Proposals for Action Understanding

    KAUST Repository

    Escorcia, Victor; Caba Heilbron, Fabian; Niebles, Juan Carlos; Ghanem, Bernard

    2016-01-01

    action proposals from long videos. We show how to take advantage of the vast capacity of deep learning models and memory cells to retrieve from untrimmed videos temporal segments, which are likely to contain actions. A comprehensive evaluation indicates

  13. Use of biocidal products (insect sprays and electro-vaporizer) in indoor areas--exposure scenarios and exposure modeling.

    Science.gov (United States)

    Berger-Preiss, Edith; Koch, Wolfgang; Gerling, Susanne; Kock, Heiko; Appel, Klaus E

    2009-09-01

    contamination of the clothing (total amounts on the whole body were 450 microg d-allethrin and 50 microg PBO for "Nexa Lotte" plug-in mosquito killer and 80 microg pyrethrins and 190 microg PBO for "Paral" plug-in mosquito killer). Human biomonitoring data revealed urine concentrations of the metabolite (E)-trans-chrysanthemum dicarboxylic acid ((E)-trans-CDCA) between 1.7 microg/l and 7.1 microg/l after 5 minutes of exposure to the different sprays. Also the use of electro-vaporizers led to (E)-trans-CDCA concentrations in the urine in the range of 1.0 microg/l to 6.2 microg/l (1-3 hours exposure period). The exposure data presented can be used for performing human risk assessment when these biocidal products were applied indoors. The airborne concentrations of the non-volatile active chemical compounds could be predicted from first principles using a deterministic exposure model (SprayExpo).

  14. Givental action and trivialisation of circle action

    NARCIS (Netherlands)

    Dotsenko, V.; Shadrin, S.; Vallette, B.

    2015-01-01

    In this paper, we show that the Givental group action on genus zero cohomological field theories, also known as formal Frobenius manifolds or hypercommutative algebras, naturally arises in the deformation theory of Batalin-Vilkovisky algebras. We prove that the Givental action is equal to an action

  15. Characterization and quantification of N-(3-aminopropyl)-N-dodecyl-1,3-propanediamine biocide by NMR, HPLC/MS and titration techniques.

    Science.gov (United States)

    Mondin, Andrea; Bogialli, Sara; Venzo, Alfonso; Favaro, Gabriella; Badocco, Denis; Pastore, Paolo

    2014-01-01

    The present paper reports the determination of the tri-amine N-(3-aminopropyl)-N-dodecyl-1,3-propanediamine (TA) present in a raw material called LONZABAC used to formulate various, widely used commercial biocides. The active principle, TA, is present in LONZABAC together with other molecules at lower concentration levels. Three independent analytical approaches, namely solution NMR spectroscopy, liquid chromatography coupled to high resolution mass spectrometry (LC/HRMS) and acid-base titration in mixed solvent, were used to overcome the problem of the non-availability of the active principle as high purity standard. NMR analysis of raw material, using a suitable internal standard, evidenced in all analyzed lots the presence of the active principle, the N-dodecyl-1,3-propanediamine (DA) and the n-dodecylamine (MA) and the absence of non-organic, NMR-inactive species. NMR peak integration led to a rough composition of the MA:DA:TA as 1:9:90. The LC/HRMS analysis allowed the accurate determination of DA and MA and confirmed in all samples the presence of the TA, which was estimated by difference: MA=1.4±0.3%, DA=11.1±0.7%, TA=87.5±1.3%. The obtained results were used to setup an easy, rapid and cheap acid-base titration method able to furnish a sufficiently accurate evaluation of the active principle both in the raw material and in diluted commercial products. For the raw material the results were: TA+MA=91.1±0.8% and DA-MA=8.9±0.8%, statistically coherent with LC/MS ones. The LC/MS approach demonstrated also its great potentialities to recognize trace of the biocide components both in environmental samples and in the formulated commercial products. Copyright © 2013 Elsevier Ltd. All rights reserved.

  16. Monitoring the performance of innovative and traditional biocides mixed with consolidants and water-repellents for the prevention of biological growth on stone.

    Science.gov (United States)

    Pinna, Daniela; Salvadori, Barbara; Galeotti, Monica

    2012-04-15

    In this study, some mixtures of consolidants or water-repellent products and biocides developed to prevent biological growth, were tested over time on three stone substrates with different bioreceptivity. The performance of both traditional (tetraethylorthosilicate, methylethoxy polysiloxane, Paraloid B72, tributyltin oxide, dibutyltin dilaurate) and innovative compounds (copper nanoparticles) was assessed using colour measurements, the water absorption by contact sponge method, and observation under stereo and optical microscopes. The application of the mixtures had also the purpose of controlling re-colonization on stone after a conservation treatment. The study site was the archaeological Area of Fiesole; the mixtures were applied in situ to sandstone, marble and plaster which had been cleaned beforehand. An innovative aspect of the study is that, by using non-invasive methods, it also permitted monitoring the mixtures' effectiveness in preventing biological growth. The monitoring results made it possible to assess the bioreceptivity of the treated stones (sandstone, marble, plaster) over a period of almost three years. The results showed that the mixtures of consolidants or water-repellent products with biocides were effective in preventing biological growth on both a substrate with low bioreceptivity like plaster and a substrate with high bioreceptivity such as marble. The innovative mixture of nano-Cu particles with a water-repellent yielded good results in terms of preventing biological colonization. Moreover, they apparently did not affect the substrates' colour. Mixtures of nano-Cu particles with a consolidant and a water-repellent hold great promise for preventing re-colonization of stone after conservation treatment. Copyright © 2012 Elsevier B.V. All rights reserved.

  17. Impulsive action and motivation.

    Science.gov (United States)

    Frijda, Nico H

    2010-07-01

    This paper explores the way in which emotions are causal determinants of action. It argues that emotional events, as appraised by the individual, elicit changes in motive states (called states of action readiness), which in turn may (or may not) cause action. Actions can be elicited automatically, without prior intention (called impulsive actions), or intentionally. Impulsive actions reflect the simplest and biologically most general form in which emotions can cause action, since they require no reflection, no foresight, and no planning. Impulsive actions are determined conjointly by the nature of action readiness, the affordances perceived in the eliciting event as appraised, and the individual's action repertoire. Those actions from one's repertoire are performed that both match the perceived affordances and the aim of the state of action readiness. Copyright © 2010 Elsevier B.V. All rights reserved.

  18. Significant NRC Enforcement Actions

    Data.gov (United States)

    Nuclear Regulatory Commission — This dataset provides a list of Nuclear Regulartory Commission (NRC) issued significant enforcement actions. These actions, referred to as "escalated", are issued by...

  19. Impulsive action and motivation

    NARCIS (Netherlands)

    Frijda, N.H.

    2010-01-01

    This paper explores the way in which emotions are causal determinants of action. It argues that emotional events, as appraised by the individual, elicit changes in motive states (called states of action readiness), which in turn may (or may not) cause action. Actions can be elicited automatically,

  20. Climate Action Team

    Science.gov (United States)

    Science Partnerships Contact Us Climate Action Team & Climate Action Initiative The Climate Action programs and the state's Climate Adaptation Strategy. The CAT members are state agency secretaries and the . See CAT reports Climate Action Team Pages CAT Home Members Working Groups Reports Back to Top

  1. Hybrid Action Systems

    DEFF Research Database (Denmark)

    Rönnkö, M.; Ravn, Anders Peter; Sere, K.

    2003-01-01

    In this paper we investigate the use of action systems with differential actions in the specifcation of hybrid systems. As the main contribution we generalize the definition of a differential action, allowing the use of arbitrary relations over model variables and their time......-derivatives in modelling continuous-time dynamics. The generalized differential action has an intuitively appealing predicate transformer semantics, which we show to be both conjunctive and monotonic. In addition, we show that differential actions blend smoothly with conventional actions in action systems, even under...... parallel composition. Moreover, as the strength of the action system formalism is the support for stepwise development by refinement, we investigate refinement involving a differential action. We show that, due to the predicate transformer semantics, standard action refinement techniques apply also...

  2. Hybrid Action Systems

    DEFF Research Database (Denmark)

    Ronkko, Mauno; Ravn, Anders P.

    1997-01-01

    a differential action, which allows differential equations as primitive actions. The extension allows us to model hybrid systems with both continuous and discrete behaviour. The main result of this paper is an extension of such a hybrid action system with parallel composition. The extension does not change...... the original meaning of the parallel composition, and therefore also the ordinary action systems can be composed in parallel with the hybrid action systems....

  3. Action of certain chemical compounds on radiation haemolysis of erythrocytes

    International Nuclear Information System (INIS)

    Kolesnikov, Yu.A.; Shulgina, M.A.; Yartsev, E.I.; Novoseltseva, S.D.; Bogatyrev, G.P.

    1975-01-01

    A radioprotective action of a number of protective chemicals on radiation haemolysis of erythrocytes has been studied. S-bearing radioprotectors, serotonin and arginine possess the highest radioprotective activity. The same radioprotectors delivered to the medium after irradiation do not influence the development of the post-irradiation haemolysis. Certain amino acids, namely proline, serine and taurine have a pronounced radio-protective action when given to the medium after irradiation, taurine producing the strongest effect on the development of radiation haemolysis. The mechanism of action of these substances is unrelated to the increased osmotic pressure of the medium and might be explained by normalization of the functional state of cytomembranes and processes of cell metabolism

  4. DAPs: Deep Action Proposals for Action Understanding

    KAUST Repository

    Escorcia, Victor

    2016-09-17

    Object proposals have contributed significantly to recent advances in object understanding in images. Inspired by the success of this approach, we introduce Deep Action Proposals (DAPs), an effective and efficient algorithm for generating temporal action proposals from long videos. We show how to take advantage of the vast capacity of deep learning models and memory cells to retrieve from untrimmed videos temporal segments, which are likely to contain actions. A comprehensive evaluation indicates that our approach outperforms previous work on a large scale action benchmark, runs at 134 FPS making it practical for large-scale scenarios, and exhibits an appealing ability to generalize, i.e. to retrieve good quality temporal proposals of actions unseen in training.

  5. [Development of a Computer-aided Diagnosis System to Distinguish between Benign and Malignant Mammary Tumors in Dynamic Magnetic Resonance Images: Automatic Detection of the Position with the Strongest Washout Effect in the Tumor].

    Science.gov (United States)

    Miyazaki, Yoshiaki; Tabata, Nobuyuki; Taroura, Tomomi; Shinozaki, Kenji; Kubo, Yuichiro; Tokunaga, Eriko; Taguchi, Kenichi

    We propose a computer-aided diagnostic (CAD) system that uses time-intensity curves to distinguish between benign and malignant mammary tumors. Many malignant tumors show a washout pattern in time-intensity curves. Therefore, we designed a program that automatically detects the position with the strongest washout effect using the technique, such as the subtraction technique, which extracts only the washout area in the tumor, and by scanning data in 2×2 pixel region of interest (ROI). Operation of this independently developed program was verified using a phantom system that simulated tumors. In three cases of malignant tumors, the washout pattern detection rate in images with manually set ROI was ≤6%, whereas the detection rate with our novel method was 100%. In one case of a benign tumor, when the same method was used, we checked that there was no washout effect and detected the persistent pattern. Thus, the distinction between benign and malignant tumors using our method was completely consistent with the pathological diagnoses made. Our novel method is therefore effective for differentiating between benign and malignant mammary tumors in dynamic magnetic resonance images.

  6. The Prose of Action

    DEFF Research Database (Denmark)

    Christiansen, Ulrik; Thrane, Sof

    2014-01-01

    risks changes over time in response to a lack of action on reported risks. In these processes Frontline Managers take on new responsibilities to make General Managers take action on reported risk. The reporting practice changes from the mere identification of risk to risk assessment and, finally......, to incorporating the possible response into the risk report. These findings add to extant literature by illustrating that actions do not automatically flow from the identification of risk. Rather, risk and action are dynamically interrelated in the sense that the prose in the risk report is a variable input...... to generate action and that a lack of action encourages managers to change their approach to reporting....

  7. From language comprehension to action understanding and back again.

    Science.gov (United States)

    Tremblay, Pascale; Small, Steven L

    2011-05-01

    A controversial question in cognitive neuroscience is whether comprehension of words and sentences engages brain mechanisms specific for decoding linguistic meaning or whether language comprehension occurs through more domain-general sensorimotor processes. Accumulating behavioral and neuroimaging evidence suggests a role for cortical motor and premotor areas in passive action-related language tasks, regions that are known to be involved in action execution and observation. To examine the involvement of these brain regions in language and nonlanguage tasks, we used functional magnetic resonance imaging (fMRI) on a group of 21 healthy adults. During the fMRI session, all participants 1) watched short object-related action movies, 2) looked at pictures of man-made objects, and 3) listened to and produced short sentences describing object-related actions and man-made objects. Our results are among the first to reveal, in the human brain, a functional specialization within the ventral premotor cortex (PMv) for observing actions and for observing objects, and a different organization for processing sentences describing actions and objects. These findings argue against the strongest version of the simulation theory for the processing of action-related language.

  8. REXPO: A catchment model designed to understand and simulate the loss dynamics of plant protection products and biocides from agricultural and urban areas

    Science.gov (United States)

    Wittmer, I. K.; Bader, H.-P.; Scheidegger, R.; Stamm, C.

    2016-02-01

    During rain events, biocides and plant protection products are transported from agricultural fields but also from urban sources to surface waters. Originally designed to be biologically active, these compounds may harm organisms in aquatic ecosystems. Although several models allow either urban or agricultural storm events to be predicted, only few combine these two sources, and none of them include biocide losses from building envelopes. This study therefore aims to develop a model designed to predict water and substance flows from urban and agricultural sources to surface waters. We developed a model based on physical principles for water percolation and substance flow including micro- (also called matrix-) and macropore-flows for the agricultural areas together with a model representing sources, sewer systems and a wastewater treatment plant for urban areas. In a second step, the combined model was applied to a catchment where an extensive field study had been conducted. The modelled and measured discharge and compound results corresponded reasonably well in terms of quantity and dynamics. The total cumulative discharge was only slightly lower than the total measured discharge (factor 0.94). The total modelled losses of the agriculturally used herbicide atrazine were slightly lower (∼25%) than the measured losses when the soil pore water distribution coefficient (describing the partition between soil particles and pore water) (Kd) was kept constant and slightly higher if it was increased with time. The modelled urban losses of diuron from facades were within a factor of three with respect to the measured values. The results highlighted the change in importance of the flow components during a rain event from urban sources during the most intensive rain period towards agricultural ones over a prolonged time period. Applications to two other catchments, one neighbouring and one on another continent showed that the model can be applied using site specific data for

  9. A flow-through aqueous standard generation system for thin film microextraction investigations of UV filters and biocides partitioning to different environmental compartments.

    Science.gov (United States)

    Ahmadi, Fardin; Sparham, Chris; Pawliszyn, Janusz

    2017-11-01

    In this paper problems associated with preparation of aqueous standard of highly hydrophobic compounds such as partial precipitation, being lost on the surfaces, low solubility in water and limited sample volume for accurate determination of their distribution coefficients are addressed. The following work presents two approaches that utilize blade thin film microextraction (TFME) to investigate partitioning of UV filters and biocides to humic acid (dissolved organic carbon) and sediment. A steady-state concentration of target analytes in water was generated using a flow-through aqueous standard generation (ASG) system. Dialysis membranes, a polytetrafluoroethylene permeation tube, and a frit porous (0.5 μm) coated by epoxy glue were basic elements used for preparation of the ASG system. In the currently presented study, negligible depletion TFME using hydrophilic-lipophilic balance (HLB) and octadecyl silica-based (C18) sorbents was employed towards the attainment of free concentration values of target analytes in the studied matrices. Thin film geometry provided a large volume of extraction phase, which improved the sensitivity of the method towards highly matrix-bound analytes. Extractions were performed in the equilibrium regime so as to prevent matrix effects and with aims to reach maximum method sensitivity for all analytes under study. Partitioning of analytes on dissolved organic carbon (DOC) was investigated in ASG to facilitate large sample volume conditions. Binding percentages and DOC distribution coefficients (Log K DOC ) ranged from 20 to 98% and 3.71-6.72, respectively. Furthermore, sediment-water partition coefficients (K d ), organic-carbon normalized partition coefficients (Log K OC ), and DOC distribution coefficients (Log K DOC ) were investigated in slurry sediment, and ranged from 33 to 2860, 3.31-5.24 and 4.52-5.75 Lkg -1 , respectively. The obtained results demonstrated that investigations utilizing ASG and TFME can yield reliable binding

  10. Action Rules Mining

    CERN Document Server

    Dardzinska, Agnieszka

    2013-01-01

    We are surrounded by data, numerical, categorical and otherwise, which must to be analyzed and processed to convert it into information that instructs, answers or aids understanding and decision making. Data analysts in many disciplines such as business, education or medicine, are frequently asked to analyze new data sets which are often composed of numerous tables possessing different properties. They try to find completely new correlations between attributes and show new possibilities for users.   Action rules mining discusses some of data mining and knowledge discovery principles and then describe representative concepts, methods and algorithms connected with action. The author introduces the formal definition of action rule, notion of a simple association action rule and a representative action rule, the cost of association action rule, and gives a strategy how to construct simple association action rules of a lowest cost. A new approach for generating action rules from datasets with numerical attributes...

  11. Recovery Action Mapping Tool

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Recovery Action Mapping Tool is a web map that allows users to visually interact with and query actions that were developed to recover species listed under the...

  12. Anti-citrullinated peptide antibodies are the strongest predictor of clinically relevant radiographic progression in rheumatoid arthritis patients achieving remission or low disease activity: A post hoc analysis of a nationwide cohort in Japan.

    Directory of Open Access Journals (Sweden)

    Tomohiro Koga

    Full Text Available To determine prognostic factors of clinically relevant radiographic progression (CRRP in patients with rheumatoid arthritis (RA achieving remission or low disease activity (LDA in clinical practice.Using data from a nationwide, multicenter, prospective study in Japan, we evaluated 198 biological disease-modifying antirheumatic drug (bDMARD-naïve RA patients who were in remission or had LDA at study entry after being treated with conventional synthetic DMARDs (csDMARDs. CRRP was defined as the yearly progression of modified total Sharp score (mTSS >3.0 U. We performed a multiple logistic regression analysis to explore the factors to predict CRRP at 1 year. We used receiver operating characteristic (ROC curve to estimate the performance of relevant variables for predicting CRRP.The mean Disease Activity Score in 28 joints-erythrocyte sedimentation rate (DAS28-ESR was 2.32 ± 0.58 at study entry. During the 1-year observation, remission or LDA persisted in 72% of the patients. CRRP was observed in 7.6% of the patients. The multiple logistic regression analysis revealed that the independent variables to predict the development of CRRP were: anti-citrullinated peptide antibodies (ACPA positivity at baseline (OR = 15.2, 95%CI 2.64-299, time-integrated DAS28-ESR during the 1 year post-baseline (7.85-unit increase, OR = 1.83, 95%CI 1.03-3.45, and the mTSS at baseline (13-unit increase, OR = 1.22, 95%CI 1.06-1.42.ACPA positivity was the strongest independent predictor of CRRP in patients with RA in remission or LDA. Physicians should recognize ACPA as a poor-prognosis factor regarding the radiographic outcome of RA, even among patients showing a clinically favorable response to DMARDs.

  13. Normative Action Research

    DEFF Research Database (Denmark)

    Baboroglu, Oguz; Ravn, Ib

    1992-01-01

    This paper presents an argument for an enrichment of action research methodology. To the current state of action research, we add a constructivist epistemological argument, as well as a crucial inspiration from some futures-oriented planning approaches. Within the domain of social....... They are generated jointly by the stakeholders of a system and the involved action researchers and are tested every time that the prescriptions for action contained in them are followed by a system's stakeholders....

  14. Emotions and action

    NARCIS (Netherlands)

    Frijda, N.H.; Manstead, A.S.R.; Frijda, N.H.; Fischer, A.H.

    2004-01-01

    This chapter discusses the relationships between emotion and action. Emotion, by its very nature, is change in action readiness to maintain or change one's relationship to an object or event. Motivation, or motivational change, is one of the key aspects of emotions. Even so, action follows only

  15. Action and Interactiv research

    DEFF Research Database (Denmark)

    Nielsen, Kurt Aagaard; Svensson, Lennart

    The text is written as a first version of editors introduction to a book about action research/interactive research in Nordic countries. You can read abouttrends and contradictions in the history of action research.The authors question the trends and demands a more explicit critical approach...... to actual action research/interactive research....

  16. A solid device based on doped hybrid composites for controlling the dosage of the biocide N-(3-aminopropyl)-N-dodecyl-1,3-propanediamine in industrial formulations.

    Science.gov (United States)

    Argente-García, A; Muñoz-Ortuño, M; Molins-Legua, C; Moliner-Martínez, Y; Campíns-Falcó, P

    2016-01-15

    A colorimetric composite device is proposed to determine the widely used biocide N-(3-aminopropyl)-N-dodecyl-1,3-propanediamine (ADP).This sensing device is based on a film of 1,2-Naphthoquinone-4-sulfonate (NQS) embedded into polydimethylsiloxane-tetraethylortosilicate-SiO2 nanoparticles composite (PDMS-TEOS-SiO2NPs). Semiquantitative analysis can be performed by visual inspection. Digitalized image or diffuse reflectance (DR) measurements can be carried out for quantitative analysis. Satisfactory detection limit (0.018%, w/v) and relative standard deviations <12% were achieved. The proposed device has been applied for the determination of ADP in detergent industrial formulations with recovery values between 80% and 112%. The method has been successfully validated, showing its high potential to control and monitor this compound because the device is easy to prepare and use, robust, portable, stable over time and cost effective. This device allows a green, simple and rapid approach for the analysis of samples without pretreatment and does not require highly trained personnel. These advantages give the proposed kit good prospects for implementation in several industries. Copyright © 2015 Elsevier B.V. All rights reserved.

  17. Biocide immobilized OMMT-carbon dot reduced Cu2O nanohybrid/hyperbranched epoxy nanocomposites: Mechanical, thermal, antimicrobial and optical properties.

    Science.gov (United States)

    De, Bibekananda; Gupta, Kuldeep; Mandal, Manabendra; Karak, Niranjan

    2015-11-01

    The present work demonstrated a transparent thermosetting nanocomposite with antimicrobial and photoluminescence attributes. The nanocomposites are fabricated by incorporation of different wt.% (1, 2 and 3) of a biocide immobilized OMMT-carbon dot reduced Cu2O nanohybrid (MITH-NH) in the hyperbranched epoxy matrix. MITH-NH is obtained by immobilization of 2-methyl-4-isothiazolin-3-one hydrochloride (MITH) at room temperature using sonication on OMMT-carbon dot reduced Cu2O nanohybid. The nanohybrid is prepared by reduction of cupric acetate using carbon dot as the reducing agent in the presence of OMMT at 70°C. The significant improvements in tensile strength (~2 fold), elongation at break (3 fold), toughness (4 fold) and initial thermal degradation temperature (30°C) of the pristine hyperbranched epoxy system are achieved by incorporation of 3wt.% of MITH-NH in it. The nanocomposites exhibit strong antimicrobial activity against Staphylococcus aureus, Bacillus subtilis, Klebsiella pneumoniae and Pseudomonas aeruginosa bacteria and Candida albicans, a fungus. The nanocomposite also shows significant activity against biofilm formation compared to the pristine thermoset. Further, the nanocomposite films emit different colors on exposure of different wavelengths of UV light. The properties of these nanocomposites are also compared with the same nanohybrid without OMMT. Copyright © 2015. Published by Elsevier B.V.

  18. Differential Equations as Actions

    DEFF Research Database (Denmark)

    Ronkko, Mauno; Ravn, Anders P.

    1997-01-01

    We extend a conventional action system with a primitive action consisting of a differential equation and an evolution invariant. The semantics is given by a predicate transformer. The weakest liberal precondition is chosen, because it is not always desirable that steps corresponding to differential...... actions shall terminate. It is shown that the proposed differential action has a semantics which corresponds to a discrete approximation when the discrete step size goes to zero. The extension gives action systems the power to model real-time clocks and continuous evolutions within hybrid systems....

  19. Creativity as action

    DEFF Research Database (Denmark)

    Glaveanu, Vlad Petre; Lubart, Todd; Bonnardel, Nathalie

    2013-01-01

    The present paper outlines an action theory of creativity and substantiates this approach by investigating creative expression in five different domains. We propose an action framework for the analysis of creative acts built on the assumption that creativity is a relational, inter......, science, scriptwriting, and music. Results point to complex models of action and inter-action specific for each domain and also to interesting patterns of similarity and differences between domains. These findings highlight the fact that creative action takes place not “inside” individual creators but “in...

  20. Action research: Scandinavian Experiences

    DEFF Research Database (Denmark)

    Rasmussen, Lauge Baungaard

    2004-01-01

    The article focus on paradigms, methods and ethics of action research in the Scandinavian countries. The special features of the action research paradigm is identified. A historical overview follows of some main action research projects in Norway, Sweden and Denmark. The tendency towards upsclae...... action research projects from organisational or small community projects yo large-scale, regional based network apporaches are also outlined and discussed. Finally, a synthesised approach of the classical, socio-technical action research approach and the large-scale network and holistic approaches...

  1. Egocentric Temporal Action Proposals.

    Science.gov (United States)

    Shao Huang; Weiqiang Wang; Shengfeng He; Lau, Rynson W H

    2018-02-01

    We present an approach to localize generic actions in egocentric videos, called temporal action proposals (TAPs), for accelerating the action recognition step. An egocentric TAP refers to a sequence of frames that may contain a generic action performed by the wearer of a head-mounted camera, e.g., taking a knife, spreading jam, pouring milk, or cutting carrots. Inspired by object proposals, this paper aims at generating a small number of TAPs, thereby replacing the popular sliding window strategy, for localizing all action events in the input video. To this end, we first propose to temporally segment the input video into action atoms, which are the smallest units that may contain an action. We then apply a hierarchical clustering algorithm with several egocentric cues to generate TAPs. Finally, we propose two actionness networks to score the likelihood of each TAP containing an action. The top ranked candidates are returned as output TAPs. Experimental results show that the proposed TAP detection framework performs significantly better than relevant approaches for egocentric action detection.

  2. PTTSA Action Plan Report

    International Nuclear Information System (INIS)

    1991-02-01

    The Pre-Tiger Team Self-Assessment (PTTSA) Report identified findings with respect to the way Sandia National Laboratories (SNL), Albuquerque, (including Tonopah Test Range (TTR) and Kauai Test Facility (KTF)) conducts its environment, safety, and health (ES ampersand H) activities. It presented Action Plan Requirements (APR) addressing these findings. The purpose of this PTTSA Action Plan Report is to assist in managing these action plan requirements by collecting, prioritizing, and estimating required resources. The specific objectives addressed by this report include: collection of requirements for the resolution of the findings presented in the PTTSA Report; consolidation of proposed Action Plan Requirements into logical Action Plan groupings for efficiency of resolution; categorization of Action Plans according to severity of the hazards represented by the findings; provision of a basis for long-range planning and issues management; documentation of the status of the proposed corrective actions; establishment of traceability of the corrective action to the original problem or issue; and integration of these plans into the existing ES ampersand H structure. The Action Plans in this report are an intermediate step between the identification of a problem or a finding in the PTTSA Report and the execution of the solution. They consist of requirements for solution, proposed actions, and an estimate of the time and (where applicable) resources required to develop the solution. This report is an input to the process of planning, resource commitment, development, testing, implementation, and maintenance of problem resolution. 2 figs

  3. Action Research for Democracy

    DEFF Research Database (Denmark)

    , to innovation policies combining Action Research with gender science. In the second part of the book epistemological and ontological dimensions of Action Research are discussed addressing questions of validity criteria related to Action Research, the transformation of knowledge institutions and the specific......Contemporary society encounters profound economical, socio-ecological and political crises challenging the democratic foundation of our societies. This book addresses the potentials and challenges for Action Research supporting democratic alternatives. It offers a broad spectrum of examples from...... Scandinavian Action Research showing different openings towards democratic development. The book’s first part contributes with a wide range of examples such as Action Research in relation to the Triple Helix/Mode II contexts, to design as a democratic process, to renewal of welfare work and public institutions...

  4. Staying mindful in action

    DEFF Research Database (Denmark)

    Svalgaard, Lotte

    2016-01-01

    Action Learning is a well-proven method to integrate ‘task’ and ‘process’, as learning about team and self (process) takes place while delivering on a task or business challenge of real importance (task). An Action Lab® is an intensive Action Learning programme lasting for 5 days, which aims...... at balancing and integrating individual challenges and business challenges, as well as the ‘Action’ and the ‘Learning’ of Action Learning. However, in spite of the aspiration to balance and integrate ‘task’ and ‘process’, a tendency and a challenge is experienced: When deeply involved in delivering...... this tendency by sharing a study looking into what hinders and promotes mindful awareness on the process, while dealing with a business challenge in an Action Lab®. Drawing on the findings, the account of practice will share some recommendations for the Action Learning facilitator to take up the challenge...

  5. Multimodal responsive action

    DEFF Research Database (Denmark)

    Oshima, Sae

    ; Raymond 2003; Schegloff and Lerner 2009), including those with multimodal actions (e.g. Olsher 2004; Fasulo & Monzoni 2009). Some responsive actions can also be completed with bodily behavior alone, such as: when an agreement display is achieved by using only nonvocal actions (Jarmon 1996), when...... the recipient’s gaze shift becomes a significant part of the speaker’s turn construction (Goodwin 1980), and when head nods show the recipient’s affiliation with the speaker’s stance (Stivers 2008). Still, much room remains for extending our current understanding of responding actions that necessarily involve...... a hairstylist and a client negotiate the quality of the service that has been provided. Here, the first action is usually the stylist’s question and/or explanation of the new cut that invites the client’s assessment/(dis)agreement, accompanied with embodied actions that project an imminent self...

  6. Historiografia wobec Action Francaise

    Directory of Open Access Journals (Sweden)

    Marek Kornat

    2009-06-01

    Full Text Available Action Franęaise in HistoriographyFrench radical right movement, Action Franęaise belongs to those political phe- nomenon in history which are differently interpreted by historiography. Principally we have eight interpretations. First ofthem is Action Franęaise own image and identity as royalist and anti-liberal "party of order”. One of the most important historical interpretation of this movement is French historian Rene Remond’s one. In his Les Droites aujourdhui Remond argued that Action Franęaise was model example of anti-liberal Right in France and in Europe of the first half of the XX century. The most popular interpretation of Action Franęaise are two: (1 Action Franęaise as an incarnation of conservative revolution (Carl Schmitt and (2 as the ideology of "integral nationalism” (Hans Konh, Carlton Hayes. Very original concept was developed by well known German historian Ernst Nolte, who considered Action Franęaise as pro- to-fascistmovement. British thinker Isaiah Berlin and Israeli historian Zeev Sternhell interpreted Action Franęaise as revolution of "anti-Enlightment” (les anti-Lumieres. Polish philosopher Stanisław Brzozowski argued that Action Franęaise was a con- seąuence of conflict between romanticism and positivism and was sure that Action Franęaise inherited much from positivistphilosophy. Non less controversial problem is forthehistorians the excommunication of Action Franęaise by Pope Pius XI in 1926. To our days there are many opposite attempts to reconstruct of this event and its origins. For many historians Pius XI tried to defend the doctrine of the Church which seemed to him intoxicated by the "nationalist and racialist heresy”. For some other writers the Vatican policy was under German influence and this caused papai action. In 1939 another Pope Pius XII decided to abolish the condemnation from 1926.

  7. Global action networks: agents for collective action

    NARCIS (Netherlands)

    Glasbergen, P.

    2010-01-01

    Global action networks (GANs) are civil society initiated multi-stakeholder arrangements that aim to fulfill a leadership role for systemic change in global governance for sustainable development. The paper develops a network approach to study some of these GANs as motivators of global collective

  8. The effective action

    International Nuclear Information System (INIS)

    DeWitt, B.

    1987-01-01

    The concept of the effective action in quantum field theory was introduced into physics by Julian Schwinger in 1954. The effective action summarizes, in a single functional, all the quantum properties of the fields under consideration. The functional derivative of the effective action yields the effective field equations, which replace the classical field equations as descriptors of the dynamical behavior of quantized fields. Solutions of these equations are 'in-out' matrix elements of the field operators and, when substituted back into the effective action itself, yield logarithms of the corresponding 'in-out' amplitudes. The classical field equations are gauge covariant, a fact that derives from the gauge invariance of the classical action. One has learned how to construct effective actions that are similarly gauge invariant (in each order of perturbation theory) and that yield effective field equations having the covariance properties of their classical analogs. Despite this advance, problems remain, stemming from the fact that there is not one but an infinite number of gauge invariant effective actions, one for every background-covariant choice of supplementary conditions and ghost fields. Vilkovisky (1984) has argued persuasively that by requiring additionally that the effective action be invariant under local invertible changes in the choice of basic field variables, one can construct a natural unique gauge invariant effective action. This lecture will examine Vilkovisky's ideas. 3 refs

  9. Stereoscopically Observing Manipulative Actions.

    Science.gov (United States)

    Ferri, S; Pauwels, K; Rizzolatti, G; Orban, G A

    2016-08-01

    The purpose of this study was to investigate the contribution of stereopsis to the processing of observed manipulative actions. To this end, we first combined the factors "stimulus type" (action, static control, and dynamic control), "stereopsis" (present, absent) and "viewpoint" (frontal, lateral) into a single design. Four sites in premotor, retro-insular (2) and parietal cortex operated specifically when actions were viewed stereoscopically and frontally. A second experiment clarified that the stereo-action-specific regions were driven by actions moving out of the frontoparallel plane, an effect amplified by frontal viewing in premotor cortex. Analysis of single voxels and their discriminatory power showed that the representation of action in the stereo-action-specific areas was more accurate when stereopsis was active. Further analyses showed that the 4 stereo-action-specific sites form a closed network converging onto the premotor node, which connects to parietal and occipitotemporal regions outside the network. Several of the specific sites are known to process vestibular signals, suggesting that the network combines observed actions in peripersonal space with gravitational signals. These findings have wider implications for the function of premotor cortex and the role of stereopsis in human behavior. © The Author 2016. Published by Oxford University Press.

  10. Action Type Deontic Logic

    DEFF Research Database (Denmark)

    Bentzen, Martin Mose

    2014-01-01

    A new deontic logic, Action Type Deontic Logic, is presented. To motivate this logic, a number of benchmark cases are shown, representing inferences a deontic logic should validate. Some of the benchmark cases are singled out for further comments and some formal approaches to deontic reasoning...... are evaluated with respect to the benchmark cases. After that follows an informal introduction to the ideas behind the formal semantics, focussing on the distinction between action types and action tokens. Then the syntax and semantics of Action Type Deontic Logic is presented and it is shown to meet...

  11. Immunization Action Coalition

    Science.gov (United States)

    ... IAC | Contact | A-Z Index | Donate | Shop | SUBSCRIBE Immunization Action Coalition Favorites ACIP Recommendations Package Inserts Additional Immunization Resources Photos Adult Vaccination Screening Checklists Ask the ...

  12. Biocidal and Sporicidal Efficacy of Pathoster® 0.35% and Pathoster® 0.50% Against Bacterial Agents in Potential Bioterrorism Use

    Science.gov (United States)

    Candeliere, Antonio; Donatiello, Adelia; Pagano, Stefania; Iatarola, Michela; Tolve, Francesco; Antonino, Leonardo; Fasanella, Antonio

    2016-01-01

    The use of products that can neutralize or significantly reduce the microbial load and that are not harmful to human health and the environment represents a milestone in the fight against the spread of infectious diseases. Peracetic acid, besides being an excellent sterilizing and sporicidal agent, is harmless to humans and the environment when it is used in a common dosage. However, the high costs and loss of efficacy of the product very quickly after its reconstitution limit its use. We evaluated the efficacy and stability of 2 commercial products, based on stabilized peracetic acid (Pathoster® 0.35% and Pathoster® 0.50%) used against spores of Bacillus anthracis and spores of Bacillus cereus and vegetative forms of Yersinia pestis, Burkholderia mallei, Burkholderia pseudomallei, Francisella tularensis, Brucella abortus, and Brucella melitensis. The efficacy tests were based on the direct contact of the products with a standard suspension of the bacteria. The stability of the products was defined as the period of time during which the biocidal and sporicidal properties remained unchanged. The limit of effectiveness was the period after which the product was unable to exert a complete sterilization after a contact of 5 minutes with at least 1 of the 8 bacteria used in this work. Both formulations showed good efficacy against the microorganisms used in the study, confirming the utility of peracetic acid as a sterilizing product. After the reconstitution, Pathoster® 0.35% was stable until 16±1 days, while Pathoster® 0.50% was stable until 24±1 days. The formulations used in this study showed good performance and a significant stability of peracetic acid. PMID:27482880

  13. Freedom in Action

    NARCIS (Netherlands)

    Miltenburg, N. van

    2015-01-01

    Free will is the capacity to select and execute one really possible action alternative. In recent years this simple libertarian picture of our capacity to freely act has drawn much criticism. Many neuroscientists claim that we do not have a capacity to select alternative courses of action since our

  14. Talk and Action

    DEFF Research Database (Denmark)

    Christensen, Lars Thøger; Morsing, Mette; Thyssen, Ole

    The aim of this paper is to analyze the relationship between organizational talk and action. Focusing in particular on the temporal dimension of this relationship, that is, the potential for talk to become action over time, we put forward ideal types of organizational strategies for possible talk...

  15. Talk and Action

    DEFF Research Database (Denmark)

    Christensen, Lars Thøger; Morsing, Mette; Thyssen, Ole

    of organizational talk and their associated activities, the paper discusses the different ways time shape the relationship between talk and action. Acknowledging that talk gives rise to different expectations over time, we put forward ideal types of organizational strategies for possible talk-action relationships...

  16. Human Actions Made Tangible

    DEFF Research Database (Denmark)

    Buur, Jacob; Caglio, Agnese; Jensen, Lars Christian

    2014-01-01

    , a method developed to engage people from different backgrounds in collaboratively analysing videos with the help of physical objects. We will present one of these tools, Action Scrabble, for analysing temporal organisation of human actions. We work with a case of skilled forklift truck driving...

  17. Action Learning in China

    Science.gov (United States)

    Marquardt, Michael J.

    2015-01-01

    Action learning was introduced into China less than 20 years ago, but has rapidly become a valuable tool for organizations seeking to solve problems, develop their leaders, and become learning organizations. This article provides an historical overview of action learning in China, its cultural underpinnings, and five case studies. It concludes…

  18. Renormalized action improvements

    International Nuclear Information System (INIS)

    Zachos, C.

    1984-01-01

    Finite lattice spacing artifacts are suppressed on the renormalized actions. The renormalized action trajectories of SU(N) lattice gauge theories are considered from the standpoint of the Migdal-Kadanoff approximation. The minor renormalized trajectories which involve representations invariant under the center are discussed and quantified. 17 references

  19. Bridging Strategies and Action

    DEFF Research Database (Denmark)

    Lehmann, Sanne

    2017-01-01

    concentrate on the way employees perceive changes. Another invention of Lewin proved to be relevant in this regard, notably action research. The application of a dialogical action research method resulted in rich empirical data, which proved the relevance of Lewin’s theoretical constructs and fed forward...

  20. Critical Utopian Action Research

    DEFF Research Database (Denmark)

    Nielsen, Birger Steen; Nielsen, Kurt Aagaard

    2016-01-01

    The specific concept of critical utopian action research is presented and discussed, as to its origin, use and potentials. The inspiration from Robert Jungk and his future creating workshops is elaborated.......The specific concept of critical utopian action research is presented and discussed, as to its origin, use and potentials. The inspiration from Robert Jungk and his future creating workshops is elaborated....

  1. Mathematics in Action

    DEFF Research Database (Denmark)

    December 2004-November 2007 Denmark, Hungary, Lithuania, the Netherlands, Norway, Slovenia and Spain have cooperated in the project Mathematics in Action (MiA). The MiA project is supported by the Grundtvig action in the Socrates program of the European Commission. The aim of the project...

  2. Introducere in Action Learning

    DEFF Research Database (Denmark)

    Clausen, Søren Witzel

    In these years action learning has become an increasing aspect of qualifying in service training of teachers in Western European countries. In this article the model of action learning which has been developed by teachers at VIA University College and introduced to the teachers at the SCAN...

  3. An Action Environment

    DEFF Research Database (Denmark)

    van den Brand, Mark; Iversen, Jørgen; Mosses, Peter David

    2004-01-01

    constructs underlying Core ML. The paper also describes the Action Environment, a new environment supporting use and validation of ASDF descriptions. The Action Environment has been implemented on top of the ASF+SDF Meta-Environment, exploiting recent advances in techniques for integration of different...... formalisms, and inheriting all the main features of the Meta-Environment....

  4. Photosensitized herbicidal action

    Energy Technology Data Exchange (ETDEWEB)

    Zweig, A; Nachtigall, G W [American Cyanamid Co., Stamford, Conn.

    1975-12-01

    The herbicidal action produced by the colorless hydrocarbon fluoranthene sprayed on the leaves of growing plants did not occur when uv radiation was removed from the light to which the plants are exposed. If the uv component of the light under which the plants were grown was augmented, the herbicidal effect of fluoranthene was increased. The mechanism of this photodynamic action is discussed.

  5. Preferential Affirmative Action.

    Science.gov (United States)

    Bell, Derrick A., Jr.

    1982-01-01

    Discusses the philosophical rationale for preferential affirmative action presented by Daniel C. Maguire in "A New American Justice." Maintains that self-interest bars present society's acceptance of Maguire's theories of justice, as demonstrated in negative reactions to the Harvard Law Review's affirmative action plan. (MJL)

  6. Actions and Decisions

    DEFF Research Database (Denmark)

    Monthoux, Pierre Guillet de

    2017-01-01

    as Aristotelian syllogistic reasoning. Her constant analytical care to defend a philosophy of action against metaphysical assumptions and taken-for-granted “psychologisms” shows that an action-perspective is as analytic as ever one of decision-making. What differs is that the latter seems constantly attracted......How management philosophy is conceived depends on if pragmatism is acknowledged or not! After having been under the main domination of management science both research and education has until recently widened its scope from a decision-making to an action-perspective. It seems to be a recent...... reconnection to pragmatism that makes the 2011 Carnegie report propose to rethink management in liberal arts terms, whilst the vastly influential 1959 Carnegie Pierson report distanced itself from American pragmatism thus focusing on decisions and forgetting actions. Actions may contain decisions and choices...

  7. Theater and action research

    DEFF Research Database (Denmark)

    Tofteng, Ditte Maria Børglum; Husted, Mia

    2011-01-01

    Action research on marginalization and exclusion often seeks to examine relations between recognition, respect, and inclusion, but addressing these topics is difficult. Theatre-based action research opens up a new way to communicate and make visible knowledge and experiences from below that have...... difficulties reaching the public agenda or influencing structures of power. In this article we follow the creation of a play and of scenes that address the life, sufferings, and wishes of unemployed people. The skills of actors, writers, and producers are worked into a critical utopian action research project...

  8. Action Investment Energy Games

    DEFF Research Database (Denmark)

    Larsen, Kim Guldstrand; Laursen, Simon; Srba, Jiri

    2012-01-01

    We introduce the formalism of action investment energy games where we study the trade-off between investments limited by given budgets and resource constrained (energy) behavior of the underlying system. More specifically, we consider energy games extended with costs of enabling actions and fixed...... budgets for each player. We ask the question whether for any Player 2 investment there exists a Player 1 investment such that Player 1 wins the resulting energy game. We study the action investment energy game for energy intervals with both upper and lower bounds, and with a lower bound only, and give...

  9. Determinants of bird conservation-action implementation and associated population trends of threatened species.

    Science.gov (United States)

    Luther, David A; Brooks, Thomas M; Butchart, Stuart H M; Hayward, Matt W; Kester, Marieke E; Lamoreux, John; Upgren, Amy

    2016-12-01

    Conservation actions, such as habitat protection, attempt to halt the loss of threatened species and help their populations recover. The efficiency and the effectiveness of actions have been examined individually. However, conservation actions generally occur simultaneously, so the full suite of implemented conservation actions should be assessed. We used the conservation actions underway for all threatened and near-threatened birds of the world (International Union for Conservation of Nature Red List of Threatened Species) to assess which biological (related to taxonomy and ecology) and anthropogenic (related to geoeconomics) factors were associated with the implementation of different classes of conservation actions. We also assessed which conservation actions were associated with population increases in the species targeted. Extinction-risk category was the strongest single predictor of the type of conservation actions implemented, followed by landmass type (continent, oceanic island, etc.) and generation length. Species targeted by invasive nonnative species control or eradication programs, ex situ conservation, international legislation, reintroduction, or education, and awareness-raising activities were more likely to have increasing populations. These results illustrate the importance of developing a predictive science of conservation actions and the relative benefits of each class of implemented conservation action for threatened and near-threatened birds worldwide. © 2016 Society for Conservation Biology.

  10. Commitment to action. Population Action International.

    Science.gov (United States)

    Squires, S

    1994-01-01

    The national chair of Population Action International (formerly the Population Crisis Committee), Robin Chandler Duke, is a crusader for women's reproductive rights. She was in Bangladesh in 1971 during its civil war. Soldiers would rape young Muslim women, and their families would reject them when they became pregnant. The head of the exiled government agreed to let physicians from IPPF perform abortions on these women, which allowed families to take them back. Opposition to the abortions arose, however. This experience in Bangladesh sparked Ms. Duke's interest in population control. Her years as the wife of a US diplomat granted her access to powerful people worldwide. Her predecessor, retired US Army General Bill Draper, called Ms. Duke from his death bed in 1974 to ask her to be national chair of PAI. She served as a delegate in various international meetings, e.g., the 1980 UNESCO meetings in Belgrade. Spain and Luxembourg honored her for her work of campaigning for women's reproductive rights. She believes that rapid population growth is the most significant problem in the world today. It exacerbates poverty, environmental destruction, and political instability. She believes that universal availability of high quality, voluntary family planning services, including safe abortion, is needed to save humanity from the vicious cycle. Since family planning, sex education, and abortion are the most personal and sensitive parts of people's lives, Population Action frames family planning in the context of basic health care. AIDS complicates the issue, because contraception is no longer limited to birth control. Even though the organization realizes that sexual abstinence is the best way to avoid AIDS, it tries to educate female teenagers not to let boys coerce them to have sex. If they do, have sex Population Action advocates condom use. Ms. Duke cites the family planning successes of Indonesia, Zimbabwe, and Thailand.

  11. 'Action 2016': AREVA's strategic action plan

    International Nuclear Information System (INIS)

    Marie, Patricia; Briand, Pauline; Floquet-Daubigeon, Fleur; Michaut, Maxime; De Scorbiac, Marie; Du Repaire, Philippine

    2011-01-01

    On December 13, 2011, Luc Oursel, CEO, and Pierre Aubouin, Chief Financial Officer presented the group's strategic plan for the period 2012-2016. The plan has been drawn up collectively and is based on a thorough-going analysis and a realistic assessment of perspectives for all group activities and associated resources. Development of nuclear and renewable energies: the fundamentals are unchanged. In this context, the German decision remains an isolated case and the great majority of nuclear programs around the world have been confirmed. More conservative in its projections than the International Energy Agency, the group expects growth of 2.2% annually, reaching 583 GW of installed nuclear capacity by 2030, against 378 GW today. However, the Fukushima accident will lead to delays in launching new programs. 'Action 2016' plan aims to consolidate AREVA's leadership in nuclear energy and become a leading player in renewable energy. The group's strategic action plan 'Action 2016' is based on the following strategic choices: - commercial priority given to value creation, - selectivity in investments, - strengthening of the financial structure. These demand an improvement in the group's performance by 2015. This plan makes nuclear safety a strategic priority for the industrial and commercial performance of the group. This ambitious performance plan for the period 2012-2016 will give the group the wherewithal to withstand a temporary slowdown in the market resulting from the Fukushima accident and to deliver safe and sustainable growth of the business. The plan sets out the strategic direction for the group's employees for the years ahead: taking advantage of the expected growth in nuclear and renewable energies, targeted investment programs, and return to self-financing as of 2014

  12. Stabilizing bottomless action theories

    International Nuclear Information System (INIS)

    Greensite, J.; Halpern, M.B.

    1983-12-01

    The authors show how to construct the Euclidean quantum theory corresponding to classical actions which are unbounded from below. The method preserves the classical limit, the large-N limit, and the perturbative expansion of the unstabilized theories. (Auth.)

  13. The Body in Action

    DEFF Research Database (Denmark)

    Grünbaum, Thor

    2008-01-01

    This article is about how to describe an agent's awareness of her bodily movements when she is aware of executing an action for a reason. Against current orthodoxy, I want to defend the claim that the agent's experience of moving has an epistemic place in the agent's awareness of her own intentio......This article is about how to describe an agent's awareness of her bodily movements when she is aware of executing an action for a reason. Against current orthodoxy, I want to defend the claim that the agent's experience of moving has an epistemic place in the agent's awareness of her own...... intentional action. In "The problem," I describe why this should be thought to be problematic. In "Motives for denying epistemic role," I state some of the main motives for denying that bodily awareness has any epistemic role to play in the content of the agent's awareness of her own action. In "Kinaesthetic...

  14. Sustainability and Entrepreneurial Action

    DEFF Research Database (Denmark)

    Korsgaard, Steffen T.; Anderson, Alistair

    Abstract Objectives - This paper explores how entrepreneurial action can lead to environmental sustainability. It builds on the assumption that the creation of sustainble practices is one of the most important challenges facing the global society, and that entrepreneurial action is a vital......: resource oriented sustainable entrepreneurial action.  Approach - The paper uses a case study approach to build deeper theoretical knowledge of environmentally sustainable entrepreneurship.  Results - The paper identifies and analyses a distinct form of sustainable entrepreneurship -  resource oriented...... entrepreneurship - which uses bricolage in various ways to create sustainable solutions. Implications and value - The concept of resource oriented sustainable entrepreneurship contributes to the theoretical understanding of how entrepreneurial action can support sustainability, Furthermore the case study has...

  15. Asthma action plan

    OpenAIRE

    Public Health Agency

    2014-01-01

    This action plans allow each child (or parent/carer) to record his or her asthma treatment to help manage their asthma when they are well, when their symptoms get worse and when they are suffering an asthma attack.

  16. Perception, Action, and Consciousness

    DEFF Research Database (Denmark)

    What is the relationship between perception and action, between an organism and its environment, in explaining consciousness? These are issues at the heart of philosophy of mind and the cognitive sciences. This book explores the relationship between perception and action from a variety of interdi......What is the relationship between perception and action, between an organism and its environment, in explaining consciousness? These are issues at the heart of philosophy of mind and the cognitive sciences. This book explores the relationship between perception and action from a variety...... of interdisciplinary perspectives, ranging from theoretical discussion of concepts to findings from recent scientific studies. It incorporates contributions from leading philosophers, psychologists, neuroscientists, and an artificial intelligence theorist. The contributions take a range of positions with respect...

  17. Groupoid Actions on Fractafolds

    Science.gov (United States)

    Ionescu, Marius; Kumjian, Alex

    2014-06-01

    We define a bundle over a totally disconnected set such that each fiber is homeomorphic to a fractal blowup. We prove that there is a natural action of a Renault-Deaconu groupoid on our fractafold bundle and that the resulting action groupoid is a Renault-Deaconu groupoid itself. We also show that when the bundle is locally compact the associated C^*-algebra is primitive and has a densely defined lower-semicontinuous trace.

  18. Action, Passion, Crises

    Directory of Open Access Journals (Sweden)

    Denis Goldberg

    2017-04-01

    Full Text Available The title of this speech is taken from a remark of the renowned Judge Oliver Wendell Holmes Jr: “When we were young our hearts were touched with fire...[and as]...life is action and passion, it is required of [one] that [one] should share the passion and action of [one’s] time, at the peril of being judged not to have lived [...

  19. Sex Steroid Actions in Male Bone

    Science.gov (United States)

    Laurent, Michaël R.; Claessens, Frank; Gielen, Evelien; Lagerquist, Marie K.; Vandenput, Liesbeth; Börjesson, Anna E.; Ohlsson, Claes

    2014-01-01

    Sex steroids are chief regulators of gender differences in the skeleton, and male gender is one of the strongest protective factors against osteoporotic fractures. This advantage in bone strength relies mainly on greater cortical bone expansion during pubertal peak bone mass acquisition and superior skeletal maintenance during aging. During both these phases, estrogens acting via estrogen receptor-α in osteoblast lineage cells are crucial for male cortical and trabecular bone, as evident from conditional genetic mouse models, epidemiological studies, rare genetic conditions, genome-wide meta-analyses, and recent interventional trials. Genetic mouse models have also demonstrated a direct role for androgens independent of aromatization on trabecular bone via the androgen receptor in osteoblasts and osteocytes, although the target cell for their key effects on periosteal bone formation remains elusive. Low serum estradiol predicts incident fractures, but the highest risk occurs in men with additionally low T and high SHBG. Still, the possible clinical utility of serum sex steroids for fracture prediction is unknown. It is likely that sex steroid actions on male bone metabolism rely also on extraskeletal mechanisms and cross talk with other signaling pathways. We propose that estrogens influence fracture risk in aging men via direct effects on bone, whereas androgens exert an additional antifracture effect mainly via extraskeletal parameters such as muscle mass and propensity to fall. Given the demographic trends of increased longevity and consequent rise of osteoporosis, an increased understanding of how sex steroids influence male bone health remains a high research priority. PMID:25202834

  20. An investigation into the relevance of action planning, theory of planned behaviour concepts, and automaticity for fruit intake action control.

    Science.gov (United States)

    de Bruijn, Gert-Jan; Wiedemann, Amelie; Rhodes, Ryan E

    2014-09-01

    In the action control framework, intention-behaviour discordance is studied around public health guidelines. Although this framework has been applied to physical activity behaviours, it has only seen very limited attention regarding fruit intake. The purpose of this study was therefore to investigate distributions and predictors of fruit intake intention-behaviour discordance. Prospective correlational design. Data were obtained from undergraduate students (n = 413) using validated questionnaires. Variables from the theory of planned behaviour, automaticity, and action planning were assessed at baseline, and fruit intake was assessed 2 weeks later. Data were analysed using discriminant function analyses and analyses of variance. The proportion of unsuccessful intenders ranged from 39.2% to 80.8%. There was a larger proportion of fruit intake intenders amongst those who reported strong automatic fruit intake. Action control was predicted by fruit intake automaticity and affective attitudes, but the strongest predictor was perceived behavioural control. No action planning items were related to fruit intake action control. There is considerable asymmetry in the intention-fruit intake relationship. An application of the action control framework may stimulate debate on the applicability of intention-based models at the public health level. What is already known on this subject? Intention is theorized to be a key construct in fruit intake. Studies in the physical activity domain indicate that nearly half of the people with positive intentions fail to subsequently act. What does this study add? The proportion of unsuccessful intenders ranged from 39.2% to 80.8%. Holding positive intentions is not sufficient to consume fruit at suggested public health guidelines. Perceived behavioural control is the most important predictor of fruit intake action control. © 2013 The British Psychological Society.

  1. Flood action plans

    International Nuclear Information System (INIS)

    Slopek, R.J.

    1995-01-01

    Safe operating procedures developed by TransAlta Utilities for dealing with flooding, resulting from upstream dam failures or extreme rainfalls, were presented. Several operating curves developed by Monenco AGRA were described, among them the No Overtopping Curve (NOC), the Safe Filling Curve (SFC), the No Spill Curve (NSC) and the Guaranteed Fill Curve (GFC). The concept of an operational comfort zone was developed and defined. A flood action plan for all operating staff was created as a guide in case of a flooding incident. Staging of a flood action plan workshop was described. Dam break scenarios pertinent to the Bow River were developed for subsequent incorporation into a Flood Action Plan Manual. Evaluation of the technical presentations made during workshops were found them to have been effective in providing operating staff with a better understanding of the procedures that they would perform in an emergency. 8 figs

  2. Facilitating Dissident Action

    DEFF Research Database (Denmark)

    Thydal, Signe; Svensson, Christian Franklin

    2018-01-01

    Firefund.net. crowdfunds and provides resources for direct action movements. The organisation positions itself within a political struggle to create a global solidarity network. Firefund.net’s challenges and possibilities are analysed in relation to juridical issues and issues of control and shar......Firefund.net. crowdfunds and provides resources for direct action movements. The organisation positions itself within a political struggle to create a global solidarity network. Firefund.net’s challenges and possibilities are analysed in relation to juridical issues and issues of control...... to support radical initiatives without breaking the law: some activists sympathise with movements in a juridical grey zone. Both issues are relevant to social movements and current direct action....

  3. Mitigation Action Plan

    Energy Technology Data Exchange (ETDEWEB)

    1994-02-01

    This Mitigation Action Plan (MAP) focuses on mitigation commitments stated in the Supplemental Environmental Impact Statement (SEIS) and the Record of Decision (ROD) for the Naval Petroleum Reserve No. 1 (NPR-1). Specific commitments and mitigation implementation actions are listed in Appendix A-Mitigation Actions, and form the central focus of this MAP. They will be updated as needed to allow for organizational, regulatory, or policy changes. It is the intent of DOE to comply with all applicable federal, state, and local environmental, safety, and health laws and regulations. Eighty-six specific commitments were identified in the SEIS and associated ROD which pertain to continued operation of NPR-1 with petroleum production at the Maximum Efficient Rate (MER). The mitigation measures proposed are expected to reduce impacts as much as feasible, however, as experience is gained in actual implementation of these measures, some changes may be warranted.

  4. Immigration Enforcement Actions - Annual Report

    Data.gov (United States)

    Department of Homeland Security — Each year, the Department of Homeland Security (DHS) undertakes immigration enforcement actions involving hundreds of thousands of foreign nationals. These actions...

  5. Appraisal of the biocide activity of products for the control of microorganisms associated with corrosive processes in the Bacia de Campos pipelines; Avaliacao da acao biocida de produtos para o controle de microrganismos associados a processos corrosivos em oledutos da Bacia de Campos

    Energy Technology Data Exchange (ETDEWEB)

    Penna, Monica de Oliveira [PETROBRAS, Rio de Janeiro, RJ (Brazil). Centro de Pesquisas. Setor de Biotecnologia e Ecossistemas]. E-mail: mpena@cenpes.petrobras.com.br; Andrade, Cynthia de Azevedo [PETROBRAS, Rio de Janeiro, RJ (Brazil). Centro de Pesquisas. Setor de Tecnologia de Materiais, Equipamentos e Corrosao]. E-mail: cynthiaandrade@cenpes.petrobras.com.br; Nascimento, Juliana Rangel do; Silva, Edilson Domingos da; Souza, Leonardo Suhett de [Fundacao GORCEIX, Ouro Preto, MG (Brazil)]. E-mail: julianarn@cenpes.petrobras.com.br; edilson@cenpes.petrobras.com.br; suhett@cenpes.petrobras.com.br

    2001-12-01

    The possible effect of corrosion inhibitors on bacteria has significant interest for the oil and gas industry since, in addition to presenting lower operational costs than biocides due to the low concentrations used, they allow a simultaneous activity on the inhibition of corrosion and adhesion of sulfate reducing-bacteria. In the case of pipes with low BSW oil fluid low, the benefit of using corrosion inhibitors in microorganism combat is even more significant in view of their dispersing characteristics during the oil phase. Herein presented are the laboratorial analysis results of the biocidal effects of six commercial products, four of which having corrosion inhibition function and two with biocidal quality. During this analysis, an oil sample collected from a Petrobras pipeline and a mixed culture of sulfate-reducing mesophilic bacteria (m-BRS) obtained from this sample were used. The study was divided in two phases: the first phase performed in semi-static conditions and, the second phase performed in dynamic conditions (loop). Compositions were analyzed according to their activities regarding the growth control of sulfate-reducing planktonic bacteria, according to their time reducing performance regarding microbial growth (activity) detection and regarding sessile bacteria (pre-adhered bacteria). Results showed that the two biocidal products had the best performance in the presence of oil and that the tetra kishidroximethyl phosphonium sulfate (THPS) at 75% was the most effective. Of the four corrosion inhibitors tested for efficiency regarding BRS growth in solution, three were slightly stimulating and the fourth was intensely stimulating. (author)

  6. Controversies on affirmative action

    Directory of Open Access Journals (Sweden)

    Milan Mesić

    2005-09-01

    Full Text Available Affirmative action was launched by American presidents J.F. Kennedy and L.B. Johnson, yet by ironic historical accident it attained its greatest expansion and most radical form during R. Nixon’s conservative administration. Affirmative action was originally a government programme aimed at improving the social position of Afro-Americans, mostly in the sphere of employment and education, as a kind of compensation for racial discrimination, and also other forms of social injustice suffered by minority and underprivileged groups. Its goal was to increase the proportion of Afro-Americans, and later members of other minorities, as well as women, in higher education institutions and in various types of employment. It was supported by many social researchers and activists. Law courts, namely their verdicts and explanations in the case of precedents, had an especially important role in the debate on affirmative action. Political conservatives attacked various affirmative action programmes (especially preferential enrolment quotas for minority students, basing their criticism on the American constitutional principles on equal rights for every citizen. Market conservatives, furthermore, claimed that the government’s policy of racial preference brought into question the very basis of the capital system (competition and at the same time was not in the interest of the Afro-American working class. Namely, the social strata that profited most was the relatively affluent segment of the Afro-American community, which only increased economic and social differences within the latter. Recently the debate on affirmative action in the US has not been limited only to two opposing sides (liberals and conservatives. More and more scientists and other participants have recognised the negative aspects and also the failures of affirmative action, while at the same time refuting conservative opinions and goals.

  7. Microfouling on biocidal and non-biocidal antifouling coatings

    Directory of Open Access Journals (Sweden)

    Thirumahal Muthukrishnan

    2015-01-01

    Full Text Available Although antifouling marine paints have been used to prevent biofouling, not much is known about their effectiveness in preventing attachment of microorganisms. The current study aims at estimating the abundance of bacteria within biofilms developed on various commercial antifouling coatings in Marina Bandar Rowdha and Marina Shangri La, Oman. Coatings tested included Pettit #1863 and #1792, West Marine #11046620, #5566252 and #10175206, Hempel Hard Racing #76484, Hempel Olympic #86950, Hempasil X3 and International YBA920. All coatings were applied on clean plastic slides. Slides without any coating were used as controls. Microbial biofilms were harvested after 2, 7 and 14 days of biofouling. Bacterial density was estimated using epifluorescence microscopy. There was a significant difference between the various treatments (coatings and control after 2, 7 and 14 days of biofouling. Although there were significant differences between both locations after 2 and 14 days of biofouling, no significant difference was observed after 7 days of biofouling at both locations. At Shangri La, the lowest bacterial density was found on International YBA920, Pettit #1792 and Hempasil X3 after 2 days, 7 days and 14 days respectively in comparison to the control treatments. However at Bandar Rowdha, International YBA920 showed the lowest bacterial density after 2 days while West Marine #10175206 showed the lowest bacterial density after both 7 days and 14 days of biofouling in comparison to the control treatment. The differential performance of tested antifouling coatings may be attributed to several factors including varying environmental conditions, difference in microfouling communities, time of exposure and physical and chemical properties of antifouling coating.

  8. Genre as Fictional Action

    DEFF Research Database (Denmark)

    Auken, Sune

    2014-01-01

    The arcticle is an interdisciplinary study between literary and rhetorical genre research. Its starting point is the well-deserved leading position held by Rhetorical Genre Studies (RGS). The article proposes a scholarly collaboration between Literary Studies and RGS and posits one possible start...... starting point for this collaboration by utilizing Carolyn Miller´s central concept of "Genre as Social Action" as a way to analyze literary characters´ social actions within narratives through an interpretation of their uses of genre....

  9. Improvisation in Action

    DEFF Research Database (Denmark)

    Bansler, Jørgen P.; Havn, Erling C.

    2003-01-01

    The paper discusses the role of extemporaneous action and bricolage in designing and implementing information systems in organizations. We report a longitudinal field study of design and implementation of a Web-based groupware application in a multinational corporation. We adopt a sensemaking...... perspective to analyze the dynamics of this process and show that improvisational action and bricolage (making do with the materials at hand) played a vital role in the development of the application. Finally, we suggest that this case study provides an occasion to reconsider how we conceptualize information...

  10. Technologies as incarnated action

    DEFF Research Database (Denmark)

    Schraube, Ernst

    Contemporary conceptualizations of technology go beyond the traditional interpretation of created things as simply neutral means to an end. They theorize technologies as objects, which embody regimes of power (the theory of technological politics), or scripts (actor-network theory), or values (cr...... represent incarnated or reified actions. I will conclude that an understanding of human activity today has to embrace an imagination of how the inherent action principles of the objects situate the activities and relationships of the subjects to themselves and to others....

  11. Action preferences and the anticipation of action outcomes

    NARCIS (Netherlands)

    Mann, D.L.; Schaefers, T.; Canal Bruland, R.

    2014-01-01

    Skilled performers of time-constrained motor actions acquire information about the action preferences of their opponents in an effort to better anticipate the outcome of that opponent's actions. However, there is reason to doubt that knowledge of an opponent's action preferences would unequivocally

  12. Our actions in my mind: Motor imagery of joint action

    DEFF Research Database (Denmark)

    Vesper, Cordula; Knoblich, Günther; Sebanz, Natalie

    2014-01-01

    How do people imagine performing actions together? The present study investigated motor imagery of joint actions that requires integrating one's own and another's part of an action. In two experiments, individual participants imagined jumping alone or jointly next to an imagined partner. The joint...... condition required coordinating one's own imagined actions with an imagined partner's actions to synchronize landing times. We investigated whether the timing of participants' own imagined jumps would reflect the difference in jump distance to their imagined partner's jumps. The results showed...... of joint jumping. These findings link research on motor imagery and joint action, demonstrating that individuals are able to integrate simulations of different parts of a joint action....

  13. Jump into Action

    Science.gov (United States)

    Ball, Stephen; Cohen, Ann; Meyer, Margaret

    2012-01-01

    Jump Into Action (JIA) is a school-based team-taught program to help fifth-grade students make healthy food choices and be more active. The JIA team (physical education teacher, classroom teacher, school nurse, and parent) work together to provide a supportive environment as students set goals to improve food choices and increase activity.…

  14. Economics Action Pack.

    Science.gov (United States)

    McDonald's Corp., Oak Brook, IL.

    One of five McDonald's Action Packs, this learning package introduces intermediate grade students to basic economic concepts. The fourteen activities include the topics of consumption (4 activities), production (5), the market system (3), a pretest, and a posttest. Specific titles under consumption include The Wonderful Treasure Tree (introduction…

  15. RPII Action Plan

    International Nuclear Information System (INIS)

    2011-03-01

    This document outlines RPII's committments under the Public Service Action Plan 2010 to 2014, otherwise known as the Croke Park Agreement. The document describes the proposed changes to the workplan, the benefits arising from the changes and the timeframe for implementing the committments

  16. Class Actions in Denmark

    DEFF Research Database (Denmark)

    Werlauff, Erik

    2009-01-01

    The article deals with the relatively new Danish Act on Class Action (Danish: gruppesøgsmål) which was suggested by The Permanent Council on Civil procedure (Retsplejerådet) of which the article's author is a member. The operability of the new provisions is illustrated through some wellknown Danish...

  17. Cognitive framing in action.

    Science.gov (United States)

    Huhn, John M; Potts, Cory Adam; Rosenbaum, David A

    2016-06-01

    Cognitive framing effects have been widely reported in higher-level decision-making and have been ascribed to rules of thumb for quick thinking. No such demonstrations have been reported for physical action, as far as we know, but they would be expected if cognition for physical action is fundamentally similar to cognition for higher-level decision-making. To test for such effects, we asked participants to reach for a horizontally-oriented pipe to move it from one height to another while turning the pipe 180° to bring one end (the "business end") to a target on the left or right. From a physical perspective, participants could have always rotated the pipe in the same angular direction no matter which end was the business end; a given participant could have always turned the pipe clockwise or counter-clockwise. Instead, our participants turned the business end counter-clockwise for left targets and clockwise for right targets. Thus, the way the identical physical task was framed altered the way it was performed. This finding is consistent with the hypothesis that cognition for physical action is fundamentally similar to cognition for higher-level decision-making. A tantalizing possibility is that higher-level decision heuristics have roots in the control of physical action, a hypothesis that accords with embodied views of cognition. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. Hope for Environmental Action

    Science.gov (United States)

    Fleischer, Barbara J.; DeMoor, Emily

    2015-01-01

    Environmental consciousness-raising programs tend to emphasize the magnitude of imminent ecological disasters, if humans continue on their current trajectory. While these environmental literacy programs also call for action to avoid cataclysmic ecological changes, psychological research on "learned helplessness" suggests that information…

  19. The action of France

    International Nuclear Information System (INIS)

    2003-01-01

    After a favorable period for the weapons mastership, the disarmament and the non-proliferation, the conditions of international safety and the strategical context revealed recently worrying developments. The France is decided to continue its action in favor of the disarmament and the non-proliferation in the continuity of its political engagements. (A.L.B.)

  20. Collective Action under Globalization

    DEFF Research Database (Denmark)

    Scheuer, Steen

    Collective action in the form of industrial conflict has declined dramatically since the high tide in the 1970s in Europe. This article argues that this decline is the result of significant changes in both economic and institutional factors, influencing the calculations of employees and of their ...

  1. Citizens' action group

    International Nuclear Information System (INIS)

    Andritzky, W.

    1978-01-01

    For the first empirical study of citizens' action groups 331 such groups were consulted. Important information was collected on the following aspects of these groups: their self-image, areas and forms of activities, objectives and their extent, how long the group has existed, successes and failures and their forms of organisation. (orig.) [de

  2. Staying Mindful in Action

    DEFF Research Database (Denmark)

    Svalgaard, Lotte

    2015-01-01

    participants in business driven action learning programmes, mutual exploration of conscious and unconscious drivers of group and individual behaviour during the programme (via working notes), and diary studies and exploratory sessions (including drawing as a method) after the programme. Socioanalytic method...

  3. Entrepreneurial learning requires action

    DEFF Research Database (Denmark)

    Brink, Tove; Madsen, Svend Ole

    2014-01-01

    that is enhanced by essential large-scale industry players and other SME managers are required to create action and value in learning. An open-mindedness to new learning approaches by SME managers and an open-mindedness to multi- and cross-disciplinary collaboration with SME managers by facilitators is required....

  4. Users in Persistant Action

    DEFF Research Database (Denmark)

    Christiansen, John K.; Gasparin, Marta; Varnes, Claus J.

    2012-01-01

    of the hybrid collective to include the press and distribution channels to want it back. All actors in collective actions can become lead users when supported by establishing alliances. This perspective is different from Von Hippel (1986) who is claiming that the trend needs to be defined before the lead users...

  5. Action and agency

    DEFF Research Database (Denmark)

    Galle, Per

    2000-01-01

    Following the Conceptual Engineering approach suggested in OAR 'The notion of product modelling', I develop a 'sufficient but minimal' philosophical understanding (in the Platonist tratidion) of agents and their actions. The motivation for this is the role of product modelling in mediating...

  6. Isotopes in action

    International Nuclear Information System (INIS)

    1987-01-01

    For most people the obvious application of nuclear technology is in power generation. But there are many other uses for radioactive materials or for products made with their help. They are found in our factories, hospitals, offices and homes. ''Isotopes in Action'' looks at the many applications of radioisotopes in our society. (author)

  7. mechanism of action

    African Journals Online (AJOL)

    known as azidothymidine) in 1987. Fourteen agents are available for general use in South Africa. Several newer compounds are in preclinical development or have ... Site of action penetration. AlJ. Thymidine. Zidovudine. Retrovir. Intracellularly;. Good activated Tcells. d4T. Thymidine. Stavudine. Zerit. Intracellularly;. Good.

  8. Intelligent robot action planning

    Energy Technology Data Exchange (ETDEWEB)

    Vamos, T; Siegler, A

    1982-01-01

    Action planning methods used in intelligent robot control are discussed. Planning is accomplished through environment understanding, environment representation, task understanding and planning, motion analysis and man-machine communication. These fields are analysed in detail. The frames of an intelligent motion planning system are presented. Graphic simulation of the robot's environment and motion is used to support the planning. 14 references.

  9. Being observed magnifies action

    NARCIS (Netherlands)

    Steinmetz, J.; Xu, Q.; Fishbach, A.; Zhang, Y.

    2016-01-01

    We test the hypothesis that people, when observed, perceive their actions as more substantial because they add the audience’s perspective to their own perspective. We find that participants who were observed while eating (Study 1) or learned they were observed after eating (Study 2) recalled eating

  10. Elements of social action

    Directory of Open Access Journals (Sweden)

    Marjanović Miloš

    2011-01-01

    Full Text Available Because of the significant analytical advantages, the author prefers social action as initial sociological concept in the relation to social phenomenon. Its basic elements are: actors, subjects and tools, needs and interests, values and norms, positions and roles. Actors set in motion and unify the rest of elements, guide to the magic triangle of sociology (movement, change, order, reaffirm actor paradigm to systemic paradigm. Subjects and tools materialize an action and its overestimate results in technological determinism or (by means of property as institutional appropriation of nature in the (unclassed historical type of society. Needs and interests are the basis of person's motivation and starting point for depth analysis of sociability. The expansion of legitimate interests circle develops techniques of normative regulation. Values and norms guide to institutional-organizational, positions to vertical and roles to horizontal structure. Values give the meaning to the action as well as to human existence, they are orientations of motivate system of personality but also basic aspect of society. As abstractions, values are latent background of norms and they tell to us what to do, and norms how to do something. Norms are specified instructions for suitable behavior Without normative order, not to be possible the satisfying of needs and the conciliation of interests. Riches, power and prestige are components of social position, and legal status is the determination of rights and obligations of the position. Roles are normative expectation of behavior. Toward kinds of sanctions roles are classified. Roles but also other elements of social action are starting point for sociological analysis of legal norms and institutes. On the other side, the observation of legal component of social actions enriches, strengths and precises sociological analysis of them.

  11. Photodegradation of three stormwater biocides

    DEFF Research Database (Denmark)

    Minelgaite, Greta; Nielsen, Asbjørn Haaning; Pedersen, Morten Lauge

    2017-01-01

    in demineralized water compared with pond water. The outdoors experiments showed limited degradation of the compounds for the duration of the test (8–17 days). The results emphasize the importance of water type, the wavelength and energy of the light when investigating pollutant’s photo fate. Also, this study...... to the accumulated light energy during the degradation time. Diuron and terbutryn were degradable under UV light following 1st order degradation kinetics, while no significant decrease of carbendazim was observed throughout the duration of experiments. Photodegradation of diuron and terbutryn was slightly faster...

  12. What's an Asthma Action Plan?

    Science.gov (United States)

    ... Educators Search English Español What's an Asthma Action Plan? KidsHealth / For Parents / What's an Asthma Action Plan? ... acción contra el asma? What's an Asthma Action Plan? An asthma action plan (or management plan) is ...

  13. How artefacts influence our actions

    NARCIS (Netherlands)

    Pols, A.J.K.

    2013-01-01

    Artefacts can influence our actions in several ways. They can be instruments, enabling and facilitating actions, where their presence affects the number and quality of the options for action available to us. They can also influence our actions in a morally more salient way, where their presence

  14. Learning Actions Models: Qualitative Approach

    DEFF Research Database (Denmark)

    Bolander, Thomas; Gierasimczuk, Nina

    2015-01-01

    In dynamic epistemic logic, actions are described using action models. In this paper we introduce a framework for studying learnability of action models from observations. We present first results concerning propositional action models. First we check two basic learnability criteria: finite ident...

  15. Partial Actions and Power Sets

    Directory of Open Access Journals (Sweden)

    Jesús Ávila

    2013-01-01

    Full Text Available We consider a partial action (X,α with enveloping action (T,β. In this work we extend α to a partial action on the ring (P(X,Δ,∩ and find its enveloping action (E,β. Finally, we introduce the concept of partial action of finite type to investigate the relationship between (E,β and (P(T,β.

  16. Body posture modulates action perception.

    Science.gov (United States)

    Zimmermann, Marius; Toni, Ivan; de Lange, Floris P

    2013-04-03

    Recent studies have highlighted cognitive and neural similarities between planning and perceiving actions. Given that action planning involves a simulation of potential action plans that depends on the actor's body posture, we reasoned that perceiving actions may also be influenced by one's body posture. Here, we test whether and how this influence occurs by measuring behavioral and cerebral (fMRI) responses in human participants predicting goals of observed actions, while manipulating postural congruency between their own body posture and postures of the observed agents. Behaviorally, predicting action goals is facilitated when the body posture of the observer matches the posture achieved by the observed agent at the end of his action (action's goal posture). Cerebrally, this perceptual postural congruency effect modulates activity in a portion of the left intraparietal sulcus that has previously been shown to be involved in updating neural representations of one's own limb posture during action planning. This intraparietal area showed stronger responses when the goal posture of the observed action did not match the current body posture of the observer. These results add two novel elements to the notion that perceiving actions relies on the same predictive mechanism as planning actions. First, the predictions implemented by this mechanism are based on the current physical configuration of the body. Second, during both action planning and action observation, these predictions pertain to the goal state of the action.

  17. Regulatory actions post - Fukushima

    International Nuclear Information System (INIS)

    Ciurea Ercau, C.

    2013-01-01

    The paper presents the results of the safety reviews performed in Romania after the Fukushima accident and the resulting actions for improving the safety. The actions taken by the National Commission for Nuclear Activities Control (CNCAN) to improve the regulatory framework include the development of new regulations and the enhancement of inspection practices, taking account of the lessons learned from the Fukushima accident. A regulation on the response to transients, accidents and emergency situations at nuclear power plants has been developed, which includes requirements on transient and accident scenarios that have to be covered by the Emergency Operating Procedures (EOPs), accident scenarios to be covered by the Severe Accident Management Guidelines (SAMGs), emergency situations to be covered by the on-site emergency response plan and emergency response procedures. (authors)

  18. INFORM'ACTION

    CERN Multimedia

    STAFF ASSOCIATION

    2010-01-01

    INFORM’ACTION Commission ! It’s all in the title ! At a time when one of the keywords is COMMUNICATE, the Staff Association has a duty to take it seriously. This is why, among other reasons, the youngest of the Staff Association internal commissions was created in 20005. As its name indicates, this commission is responsible for INFORMING, TRAINING (FORMER) and organizing ACTIONs. INFORMING : The members of this commission endeavour to work using all imaginable and known channels of information: articles, emails, alerts, posters, web site, organizing meetings, distributing flyers, banners, videos, etc. In 2009 a new web site (http://cern.ch/association) was put on line.   Since then this site has been continually updated to provide information regarding the latest news in the social domain (Pension Fund, CHIS, 5YR), and also special offers for our members, club news, and social and cultural activities. In 2009 and 2010, the Staff Association notice boards were ...

  19. Action against Kruemmel rejected

    International Nuclear Information System (INIS)

    Anon.

    1976-01-01

    In its verdict dated September 2nd, 1976 - 10 A 211/74 -, the administrative court of Schleswig-Holstein at Schleswig has rejected with costs the action of a plaintiff resident in Hessen concerning the contestation of the 2nd partial licence for the erection of a nuclear power station at Kruemmel near Hamburg. The verdict is not subject to appeal. Furthermore, the administrative court of Schleswig-Holstein at Schleswig, in its verdict dated September 2nd, 1976 - 10 A 214/74 - has rejected with costs the actions of eight plaintiffs living in Hamburg and surroundings, concerning the contestation of the 1st, 2nd and 3rd partial licence for the erection of a nuclear power station at Kruemmel near Hamburg. An appeal against this verdict has been lodged at the higher administrative court at Lueneburg. The main gounds for the two judgments are given in full text. (orig./HP) [de

  20. Institutional Logics in Action

    DEFF Research Database (Denmark)

    Lounsbury, Michael; Boxenbaum, Eva

    2013-01-01

    This double volume presents state-of-the-art research and thinking on the dynamics of actors and institutional logics. In the introduction, we briefly sketch the roots and branches of institutional logics scholarship before turning to the new buds of research on the topic of how actors engage...... institutional logics in the course of their organizational practice. We introduce an exciting line of new works on the meta-theoretical foundations of logics, institutional logic processes, and institutional complexity and organizational responses. Collectively, the papers in this volume advance the very...... prolific stream of research on institutional logics by deepening our insight into the active use of institutional logics in organizational action and interaction, including the institutional effects of such (inter)actions....

  1. From Knowledge to Action

    DEFF Research Database (Denmark)

    Hjelmar, Ulf; Møller, Anne Mette

    2016-01-01

    In recent years, focus has been on the utilisation of research-based knowledge and evidence in social work policy and practice in order to make it more effective. A part of this process has been the launch of knowledge portals to make use of knowledge from research. In this article, we investigate...... how knowledge portals about vulnerable children and youth present knowledge and evidence, and how they try to work as ?knowledge brokers? or intermediaries of evidence. We argue that knowledge portals are not merely channels for dissemination of knowledge. Knowledge portals could be considered as part...... of a greater process of bringing knowledge to action, encompassing the social and organisational contexts of research utilisation. The article concludes by stating that knowledge portals have the potential to be effective instruments in knowledge-to-action processes. The two main challenges, however...

  2. RE_ACTION

    DEFF Research Database (Denmark)

    This book investigates the ways in which new digital media may enhance the experience of the art-archive. Taken as a whole, the new media is a vital component of a 'transdisciplinary' and transformative field, a cultural landscape that is changing rapidly the conditions and domains of the archive...... of the project was presented at the exhibition TOTAL_ACTION - Art in the New Media Landscape at the Museum of Contemporary Art in Roskilde, Denmark, from October through November 2008....

  3. Students in Action Initiative

    OpenAIRE

    Ryan, Theresa; Mottiar, Ziene; Quinn, Bernadette; Gorman, Catherine; Griffin, Kevin; Craggs, Ruth; Quinn, Deirdre

    2015-01-01

    The Students in Action Project in the School of Hospitality Management and Tourism was established in 2012 as a way of engaging students and working with stakeholders in a destination. The overall aim of the project was to immerse students in an active collaborative learning environment within the destination to identify ways in which tourism could be enhanced. In the 2014/2015 academic year the project involved over 300 students from a variety of programmes and modules working with local sta...

  4. Hearing sounds, understanding actions: action representation in mirror neurons.

    Science.gov (United States)

    Kohler, Evelyne; Keysers, Christian; Umiltà, M Alessandra; Fogassi, Leonardo; Gallese, Vittorio; Rizzolatti, Giacomo

    2002-08-02

    Many object-related actions can be recognized by their sound. We found neurons in monkey premotor cortex that discharge when the animal performs a specific action and when it hears the related sound. Most of the neurons also discharge when the monkey observes the same action. These audiovisual mirror neurons code actions independently of whether these actions are performed, heard, or seen. This discovery in the monkey homolog of Broca's area might shed light on the origin of language: audiovisual mirror neurons code abstract contents-the meaning of actions-and have the auditory access typical of human language to these contents.

  5. Development and Certification of Station Development Test Objective (SDTO) Experiment # 15012-U, "Near RealTime Water Quality Monitoring Demonstration for ISS Biocides Using Colorimetric Solid Phase Extraction (CSPE)"

    Science.gov (United States)

    Gazda, Daniel B.; Nolan, Daniel J.; Rutz, Jeffrey A.; Shcultz, John R.; Siperko, Lorraine M.; Porter, Marc D,; Lipert, Robert J.; Limardo, Jose G.; McCoy, J. Torin

    2009-01-01

    Scientists and engineers from the Wyle Integrated Science and Engineering Group are working with researchers at the University of Utah and Iowa State University to develop and certify an experimental water quality monitoring kit based on Colorimetric Solid Phase Extraction (CSPE). The kit will be launched as a Station Development Test Objective (SDTO) experiment and evaluated on the International Space Station (ISS) to determine the acceptability of CSPE technology for routine inflight water quality monitoring. Iodine and silver, the biocides used in the US and Russian on-orbit water systems, will serve as test analytes for the technology evaluation. This manuscript provides an overview of the CSPE SDTO experiment and details the development and certification of the experimental water quality monitoring kit. Initial results from reagent and standard solution stability testing and environmental testing performed on the kit hardware are also reported.

  6. Empirical microeconomics action functionals

    Science.gov (United States)

    Baaquie, Belal E.; Du, Xin; Tanputraman, Winson

    2015-06-01

    A statistical generalization of microeconomics has been made in Baaquie (2013), where the market price of every traded commodity, at each instant of time, is considered to be an independent random variable. The dynamics of commodity market prices is modeled by an action functional-and the focus of this paper is to empirically determine the action functionals for different commodities. The correlation functions of the model are defined using a Feynman path integral. The model is calibrated using the unequal time correlation of the market commodity prices as well as their cubic and quartic moments using a perturbation expansion. The consistency of the perturbation expansion is verified by a numerical evaluation of the path integral. Nine commodities drawn from the energy, metal and grain sectors are studied and their market behavior is described by the model to an accuracy of over 90% using only six parameters. The paper empirically establishes the existence of the action functional for commodity prices that was postulated to exist in Baaquie (2013).

  7. Archetypes as action patterns.

    Science.gov (United States)

    Hogenson, George B

    2009-06-01

    The discovery of mirror neurons by researchers at the University of Parma promises to radically alter our understanding of fundamental cognitive and affective states. This paper explores the relationship of mirror neurons to Jung's theory of archetypes and proposes that archetypes may be viewed as elementary action patterns. The paper begins with a review of a proposed interpretation of the fainting spells of S. Freud in his relationship with Jung as an example of an action pattern that also defines an archetypal image. The challenge that mirror neurons present to traditional views in analytical psychology and psychoanalysis, however, is that they operate without recourse to a cognitive processing element. This is a position that is gaining increasing acceptance in other fields as well. The paper therefore reviews the most recent claims made by the Boston Process of Change Study Group as well as conclusions drawn from dynamic systems views of development and theoretical robotics to underline the conclusion that unconscious agency is not a requirement for coherent action. It concludes with the suggestion that this entire body of research may lead to the conclusion that the dynamic unconscious is an unnecessary hypothesis in psychoanalysis and analytical psychology.

  8. Knowledge into Action

    DEFF Research Database (Denmark)

    Larsen, Lars Thorup

    In the 1970s, most Western nations began to shift the emphasis of health care provision from treatment to prevention. While originally motivated by the rise of lifestyle diseases, the emergence of the new public health policy mainly involves a new way to understand and structure the relationship ...... in the production and circulation of health knowledge, which attempts to replace the usual 'ifs, buts and maybes' of medical science with an action-minded public health knowledge just telling people what to do.......In the 1970s, most Western nations began to shift the emphasis of health care provision from treatment to prevention. While originally motivated by the rise of lifestyle diseases, the emergence of the new public health policy mainly involves a new way to understand and structure the relationship...... between health knowledge and individual action. The book investigates what political rationality characterizes this new ambition in public health policies to put knowledge into action in the hands of individual citizens and how these policies adapt to the continuous experience that citizens often do...

  9. Bring learning into action

    Directory of Open Access Journals (Sweden)

    Annemieke van den Berg

    2018-05-01

    Full Text Available Context: This critical reflection is about the positive effects for educational and research settings of participation in a two-day programme entitled ‘Using participatory action research and appreciative inquiry to research healthcare practice’. Aims: To reflect on the journey of positive developments in research and education that started with participation in this programme. Using Caring Conversations (Dewar, 2011 as a reflective framework of questions, this article discusses the journey in order to encourage others to consider the approach of appreciative inquiry to bring to life the concept of co-creation in research and education. Conclusions and implications for practice: Participation in this programme has led to the implementation of a variety of actions in educational and research settings. Central to all these actions is an appreciative approach to co-creation as a counterpart to today’s prevailing problem-based viewpoint. A possible factor behind these developments was the power of vulnerability experienced during the programme, a shared process of transformational learning. Implications for practice: This critical reflection: Provides an invitation to shift from a problem-based focus to a positive revolution Provides an appreciative reflective story about the power of vulnerability as an inspiration for others to move out of their comfort zone and seek to discover their own exceptionality Supports a shift from a facilitator-led to a co-creation approach in doing research and teaching with older adults

  10. Finding minimal action sequences with a simple evaluation of actions

    Science.gov (United States)

    Shah, Ashvin; Gurney, Kevin N.

    2014-01-01

    Animals are able to discover the minimal number of actions that achieves an outcome (the minimal action sequence). In most accounts of this, actions are associated with a measure of behavior that is higher for actions that lead to the outcome with a shorter action sequence, and learning mechanisms find the actions associated with the highest measure. In this sense, previous accounts focus on more than the simple binary signal of “was the outcome achieved?”; they focus on “how well was the outcome achieved?” However, such mechanisms may not govern all types of behavioral development. In particular, in the process of action discovery (Redgrave and Gurney, 2006), actions are reinforced if they simply lead to a salient outcome because biological reinforcement signals occur too quickly to evaluate the consequences of an action beyond an indication of the outcome's occurrence. Thus, action discovery mechanisms focus on the simple evaluation of “was the outcome achieved?” and not “how well was the outcome achieved?” Notwithstanding this impoverishment of information, can the process of action discovery find the minimal action sequence? We address this question by implementing computational mechanisms, referred to in this paper as no-cost learning rules, in which each action that leads to the outcome is associated with the same measure of behavior. No-cost rules focus on “was the outcome achieved?” and are consistent with action discovery. No-cost rules discover the minimal action sequence in simulated tasks and execute it for a substantial amount of time. Extensive training, however, results in extraneous actions, suggesting that a separate process (which has been proposed in action discovery) must attenuate learning if no-cost rules participate in behavioral development. We describe how no-cost rules develop behavior, what happens when attenuation is disrupted, and relate the new mechanisms to wider computational and biological context. PMID:25506326

  11. What good are actions? Accelerating learning using learned action priors

    CSIR Research Space (South Africa)

    Rosman, Benjamin S

    2012-11-01

    Full Text Available The computational complexity of learning in sequential decision problems grows exponentially with the number of actions available to the agent at each state. We present a method for accelerating this process by learning action priors that express...

  12. Learning about goals : development of action perception and action control

    NARCIS (Netherlands)

    Verschoor, Stephan Alexander

    2014-01-01

    By using innovative paradigms, the present thesis provides convincing evidence that action-effect learning, and sensorimotor processes in general play a crucial role in the development of action- perception and production in infancy. This finding was further generalized to sequential action.

  13. Experiencing Action Evaluation's Cyclic Process: Partnering Conflict, Reflection, and Action

    Science.gov (United States)

    Burrows, Andrea C.; Harkness, Shelly Sheats

    2016-01-01

    In this article, the authors describe experiences in and offer suggestions from a course entitled "Educational Innovation for Excellence Through Action Research, Conflict Resolution, and Organizational Learning"--an action evaluation (AE). The class was taught using the principles of action research and AE. The authors explore the impact…

  14. Blandford's argument: The strongest continuous gravitational wave signal

    International Nuclear Information System (INIS)

    Knispel, Benjamin; Allen, Bruce

    2008-01-01

    For a uniform population of neutron stars whose spin-down is dominated by the emission of gravitational radiation, an old argument of Blandford states that the expected gravitational-wave amplitude of the nearest source is independent of the deformation and rotation frequency of the objects. Recent work has improved and extended this argument to set upper limits on the expected amplitude from neutron stars that also emit electromagnetic radiation. We restate these arguments in a more general framework, and simulate the evolution of such a population of stars in the gravitational potential of our galaxy. The simulations allow us to test the assumptions of Blandford's argument on a realistic model of our galaxy. We show that the two key assumptions of the argument (two dimensionality of the spatial distribution and a steady-state frequency distribution) are in general not fulfilled. The effective scaling dimension D of the spatial distribution of neutron stars is significantly larger than two, and for frequencies detectable by terrestrial instruments the frequency distribution is not in a steady state unless the ellipticity is unrealistically large. Thus, in the cases of most interest, the maximum expected gravitational-wave amplitude does have a strong dependence on the deformation and rotation frequency of the population. The results strengthen the previous upper limits on the expected gravitational-wave amplitude from neutron stars by a factor of 6 for realistic values of ellipticity.

  15. The Philippine tobacco industry: "the strongest tobacco lobby in Asia".

    Science.gov (United States)

    Alechnowicz, K; Chapman, S

    2004-12-01

    To highlight revelations from internal tobacco industry documents about the conduct of the industry in the Philippines since the 1960s. Areas explored include political corruption, health, employment of consultants, resisting pack labelling, and marketing and advertising. Systematic keyword Minnesota depository website searches of tobacco industry internal documents made available through the Master Settlement Agreement. The Philippines has long suffered a reputation for political corruption where collusion between state and business was based on the exchange of political donations for favourable economic policies. The tobacco industry was able to limit the effectiveness of proposed anti-tobacco legislation. A prominent scientist publicly repudiated links between active and passive smoking and disease. The placement of health warning labels was negotiated to benefit the industry, and the commercial environment allowed it to capitalise on their marketing freedoms to the fullest potential. Women, children, youth, and the poor have been targeted. The politically laissez faire Philippines presented tobacco companies with an environment ripe for exploitation. The Philippines has seen some of the world's most extreme and controversial forms of tobacco promotion flourish. Against international standards of progress, the Philippines is among the world's slowest nations to take tobacco control seriously.

  16. Create positive contraceptive images for strongest impact in single lesson.

    Science.gov (United States)

    1987-05-01

    Health educators attempting to deliver contraceptive information to adolescents in the classroom must seek ways to make a major impact in a very short period of time. A Planned Parenthood professional from New Jersey has developed a single-shot birth control lesson that, rather than presenting the pros and cons of various contraceptive methods, has teenagers identify themselves as at high, low, or no risk of pregnancy. Students estimate the number of classmates who are in each category and then assess whether they personally are at risk of an unintended pregnancy. In general, teens overestimate the number of classmates who are sexually active. This approach seems to make the ensuing discussion of contraceptive methods more meaningful. This discussion presents the condom and foam, the sponge, and visiting a family planning clinic. After this 40 minute presentation, fewer adolescents report being afraid of contraceptive side effects; they also have more knowledge about the efficacy and availability of different methods. A lesson in preparation is centered around a videotape entitled "Swept Away is Not Okay." It shows a teen couple going to a family planning clinic before they ever have intercourse. This strategy of encouraging adolescents to seek contraception before sexual involvement begins is considered more realistic than pressuring teens to abstain from sex. School officials and teachers have been receptive to this educational approach, viewing it as presenting important public health information.

  17. The Strength of the Strongest Ties in Collaborative Problem Solving

    DEFF Research Database (Denmark)

    de Montjoye, Yves-Alexandre; Stopczynski, Arkadiusz; Shmueli, Erez

    2014-01-01

    an effect on performance. Both networks of strong ties explain more of the variance than other factors, such as measured or self-evaluated technical competencies, or the personalities of the team members. In fact, the inclusion of the network of strong ties renders these factors non...

  18. Strongest gravitational waves from neutrino oscillations at supernova core bounce

    International Nuclear Information System (INIS)

    Mosquera Cuesta, H.J.; Fiuza, K.

    2004-01-01

    Resonant active-to-active (ν a →ν a ), as well as active-to-sterile (ν a →ν s ) neutrino (ν) oscillations can take place during the core bounce of a supernova collapse. Besides, over this phase, weak magnetism increases the antineutrino (anti ν) mean free path, and thus its luminosity. Because the oscillation feeds mass-energy into the target ν species, the large mass-squared difference between the species (ν a →ν s ) implies a huge amount of energy to be given off as gravitational waves (L GW ∝10 49 erg s -1 ), due to anisotropic but coherent ν flow over the oscillation length. This asymmetric ν-flux is driven by both the spin-magnetic and the universal spin-rotation coupling. The novel contribution of this paper stems from (1) the new computation of the anisotropy parameter α∝0.1-0.01, and (2) the use of the tight constraints from neutrino experiments as SNO and KamLAND, and the cosmic probe WMAP, to compute the gravitational-wave emission during neutrino oscillations in supernovae core collapse and bounce. We show that the mass of the sterile neutrino ν s that can be resonantly produced during the flavor conversions makes it a good candidate for dark matter as suggested by Fuller et al., Phys. Rev. D 68, 103002 (2003). The new spacetime strain thus estimated is still several orders of magnitude larger than those from ν diffusion (convection and cooling) or quadrupole moments of neutron star matter. This new feature turns these bursts into the more promising supernova gravitational-wave signals that may be detected by observatories as LIGO, VIRGO, etc., for distances far out to the VIRGO cluster of galaxies. (orig.)

  19. Planning an action.

    Science.gov (United States)

    Gentilucci, M; Negrotti, A; Gangitano, M

    1997-06-01

    The motor control of a sequence of two motor acts forming an action was studied in the present experiment. The two analysed motor acts were reaching-grasping an object (first target) and placing it on a second target of the same shape and size (experiment 1). The aim was to determine whether extrinsic properties of the second target (i.e. target distance) could selectively influence the kinematics of reaching and grasping. Distance, position and size of both targets were randomly varied across the experimental session. The kinematics of the initial phase of the first motor act, that is, velocity of reaching and hand shaping of grasping, were influenced by distance of the second target. No kinematic difference was found between movements executed with and without visual control of both hand and targets. These results could be due to computation of the general program of an action that takes into account extrinsic properties of the final target. Conversely, they could depend on a visual interference effect produced by the near second target on the control of the first motor act. In order to dissociate the effects due to second target distance from those due to visual interference, two control experiments were carried out. In the first control experiment (experiment 2) subjects executed movements directed towards spatial locations at different distances from the first target, as in experiment 1. However, the near second target was not presented and subjects were required to place the object on an arbitrary near position. Distance of the second (either real or arbitrary) target affected the reaching component of the first motor act, as in experiment 1, but not the grasp component. In the second control experiment (experiment 3), the pure visual interference effect was tested. Subjects were required to reach and grasp the object and to lift it in either presence or absence of a second near stimulus. No effect on the initial phase of the first motor act was observed. The

  20. VIOLENT FRAMES IN ACTION

    Energy Technology Data Exchange (ETDEWEB)

    Sanfilippo, Antonio P.; McGrath, Liam R.; Whitney, Paul D.

    2011-11-17

    We present a computational approach to radical rhetoric that leverages the co-expression of rhetoric and action features in discourse to identify violent intent. The approach combines text mining and machine learning techniques with insights from Frame Analysis and theories that explain the emergence of violence in terms of moral disengagement, the violation of sacred values and social isolation in order to build computational models that identify messages from terrorist sources and estimate their proximity to an attack. We discuss a specific application of this approach to a body of documents from and about radical and terrorist groups in the Middle East and present the results achieved.