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Sample records for monovalent cationic pesticide

  1. Activation and inhibition of histone deacetylase 8 by monovalent cations.

    Science.gov (United States)

    Gantt, Stephanie L; Joseph, Caleb G; Fierke, Carol A

    2010-02-26

    The metal-dependent histone deacetylases (HDACs) catalyze hydrolysis of acetyl groups from acetyllysine side chains and are targets of cancer therapeutics. Two bound monovalent cations (MVCs) of unknown function have been previously observed in crystal structures of HDAC8; site 1 is near the active site, whereas site 2 is located > 20 A from the catalytic metal ion. Here we demonstrate that one bound MVC activates catalytic activity (K(1/2) = 3.4 mM for K(+)), whereas the second, weaker-binding MVC (K(1/2) = 26 mM for K(+)) decreases catalytic activity by 11-fold. The weaker binding MVC also enhances the affinity of the HDAC inhibitor suberoylanilide hydroxamic acid by 5-fold. The site 1 MVC is coordinated by the side chain of Asp-176 that also forms a hydrogen bond with His-142, one of two histidines important for catalytic activity. The D176A and H142A mutants each increase the K(1/2) for potassium inhibition by > or = 40-fold, demonstrating that the inhibitory cation binds to site 1. Furthermore, the MVC inhibition is mediated by His-142, suggesting that this residue is protonated for maximal HDAC8 activity. Therefore, His-142 functions either as an electrostatic catalyst or a general acid. The activating MVC binds in the distal site and causes a time-dependent increase in activity, suggesting that the site 2 MVC stabilizes an active conformation of the enzyme. Sodium binds more weakly to both sites and activates HDAC8 to a lesser extent than potassium. Therefore, it is likely that potassium is the predominant MVC bound to HDAC8 in vivo.

  2. Independent adsorption of monovalent cations and cationic polymers at PE/PG lipid membranes

    Science.gov (United States)

    Khomich, Daria A.; Nesterenko, Alexey M.; Kostritskii, Andrei Yu; Kondinskaia, Diana A.; Ermakov, Yuri A.; Gurtovenko, Andrey A.

    2017-01-01

    Synthetic cationic polymers constitute a wide class of polymeric biocides. Commonly their antimicrobial effect is associated to their interaction with bacterial membranes. In the present study we analyze the interaction of various cationic polymers with model bacterial membranes comprised of a mixture of phosphatidylethanolamine (PE) and phosphatidylglycerol (PG). We describe a polymer-membrane interaction as a process of modification of the surface charge. It is well known that small monovalent inorganic cations (Na+, K+) cannot overcharge the surface of a bilayer containing anionic lipids. In contrast, polycations are able to overcharge anionic membranes and demonstrate a very large input to the electric field distribution at the membrane-water interface. We aimed here to study the electrostatic effects associated with the interaction of polycations of different types with a model lipid membrane whose composition closely resembles that of bacterial membranes (PE:PG = 1:4). Four different cationic polymers (polyvinylamine, polyallylamine, poly-L-lysine and polyethylenimine) were adsorbed at a model PE/PG bilayer in MD simulations. Adsorption of sodium cations was inspected separately for PE/PG bilayers of different composition and cation’s binding parameters were determined. From computational experiments and consequent theoretical analysis we concluded that sodium adsorption at anionic binding sites does not depend on the presence of polycations. Therefore, we hypothesize that antimicrobial activity of the studied cationic polymers should depend on the ionic composition of the medium.

  3. The Mrp system: a giant among monovalent cation/proton antiporters?

    Science.gov (United States)

    Swartz, Talia H; Ikewada, Sayuri; Ishikawa, Osamu; Ito, Masahiro; Krulwich, Terry Ann

    2005-10-01

    Mrp systems are a novel and broadly distributed type of monovalent cation/proton antiporter of bacteria and archaea. Monovalent cation/proton antiporters are membrane transport proteins that catalyze efflux of cytoplasmic sodium, potassium or lithium ions in exchange for external hydrogen ions (protons). Other known monovalent cation antiporters are single gene products, whereas Mrp systems have been proposed to function as hetero-oligomers. A mrp operon typically has six or seven genes encoding hydrophobic proteins all of which are required for optimal Mrp-dependent sodium-resistance. There is little sequence similarity of Mrp proteins to other antiporters but three of these proteins have significant sequence similarity to membrane embedded subunits of ion-translocating electron transport complexes. Mrp antiporters have essential roles in the physiology of alkaliphilic and neutralophilic Bacillus species, nitrogen-fixing Sinorhizobium meliloti and in the pathogen Staphylococcus aureus, although these bacteria contain multiple monovalent cation/proton antiporters. The wide distribution of Mrp systems leads to the anticipation of important roles in an even wider variety of pathogens, extremophiles and environmentally important organisms. Here, the distribution, established physiological roles and catalytic activities of Mrp systems are reviewed, hypotheses regarding their complexity are discussed and major open questions about their function are highlighted.

  4. Incorporation of Monovalent Cations in Sulfate Green Rust

    DEFF Research Database (Denmark)

    Christiansen, B. C.; Dideriksen, K.; Katz, A.;

    2014-01-01

    Green rust is a naturally occurring layered mixed-valent ferrous-ferric hydroxide, which can react with a range of redox-active compounds. Sulfate-bearing green rust is generally thought to have interlayers composed of sulfate and water. Here, we provide evidence that the interlayers also contain...... with water showed that Na+ and K+ were structurally fixed in the interlayer, whereas Rb+ and Cs+ could be removed, resulting in a decrease in the basal layer spacing. The incorporation of cations in the interlayer opens up new possibilities for the use of sulfate green rust for exchange reactions with both...

  5. Effects of monovalent cations on folding kinetics of G-quadruplexes.

    Science.gov (United States)

    You, Jing; Li, Hui; Lu, Xi-Ming; Li, Wei; Wang, Peng-Ye; Dou, Shuo-Xing; Xi, Xu-Guang

    2017-08-31

    G-quadruplexes are special structures existing at the ends of human telomeres, the folding kinetics of which are essential for their functions, such as in the maintenance of genome stability and the protection of chromosome ends. In the present study, we investigated the folding kinetics of G-quadruplex in different monovalent cation environments and determined the detailed kinetic parameters for Na(+)- and K(+)-induced G-quadruplex folding, and for its structural transition from the basket-type Na(+) form to the hybrid-type K(+) form. More interestingly, although Li(+) was often used in previous studies of G-quadruplex folding as a control ion supposed to have no effect, we have found that Li(+) can actually influence the folding kinetics of both Na(+)- and K(+)-induced G-quadruplexes significantly and in different ways, by changing the folding fraction of Na(+)-induced G-quadruplexes and greatly increasing the folding rates of K(+)-induced G-quadruplexes. The present study may shed new light on the roles of monovalent cations in G-quadruplex folding and should be useful for further studies of the underlying folding mechanism. © 2017 The Author(s).

  6. Circular Dichroism is Sensitive to Monovalent Cation Binding in Monensin Complexes.

    Science.gov (United States)

    Nedzhib, Ahmed; Kessler, Jiří; Bouř, Petr; Gyurcsik, Béla; Pantcheva, Ivayla

    2016-05-01

    Monensin is a natural antibiotic that exhibits high affinity to certain metal ions. In order to explore its potential in coordination chemistry, circular dichroism (CD) spectra of monensic acid A (MonH) and its derivatives containing monovalent cations (Li(+) , Na(+) , K(+) , Rb(+) , Ag(+) , and Et4 N(+) ) in methanolic solutions were measured and compared to computational models. Whereas the conventional CD spectroscopy allowed recording of the transitions down to 192 nm, synchrotron radiation circular dichroism (SRCD) revealed other bands in the 178-192 nm wavelength range. CD signs and intensities significantly varied in the studied compounds, in spite of their similar crystal structure. Computational modeling based on the Density Functional Theory (DFT) and continuum solvent model suggests that the solid state monensin structure is largely conserved in the solutions as well. Time-dependent Density Functional Theory (TDDFT) simulations did not allow band-to-band comparison with experimental spectra due to their limited precision, but indicated that the spectral changes were caused by a combination of minor conformational changes upon the monovalent cation binding and a direct involvement of the metal electrons in monensin electronic transitions. Both the experiment and simulations thus show that the CD spectra of monensin complexes are very sensitive to the captured ions and can be used for their discrimination. Chirality 28:420-428, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  7. Influence of competing inorganic cations on the ion exchange equilibrium of the monovalent organic cation metoprolol on natural sediment.

    Science.gov (United States)

    Niedbala, Anne; Schaffer, Mario; Licha, Tobias; Nödler, Karsten; Börnick, Hilmar; Ruppert, Hans; Worch, Eckhard

    2013-02-01

    The aim of this study was to systematically investigate the influence of the mono- and divalent inorganic ions Na(+) and Ca(2+) on the sorption behavior of the monovalent organic cation metoprolol on a natural sandy sediment at pH=7. Isotherms for the beta-blocker metoprolol were obtained by sediment-water batch tests over a wide concentration range (1-100000 μg L(-1)). Concentrations of the competing inorganic ions were varied within freshwater relevant ranges. Data fitted well with the Freundlich sorption model and resulted in very similar Freundlich exponents (n=0.9), indicating slightly non-linear behavior. Results show that the influence of Ca(2+) compared to Na(+) is more pronounced. A logarithmic correlation between the Freundlich coefficient K(Fr) and the concentration or activity of the competing inorganic ions was found allowing the prediction of metoprolol sorption on the investigated sediment at different electrolyte concentrations. Additionally, the organic carbon of the sediment was completely removed for investigating the influence of organic matter on the sorption of metoprolol. The comparison between the experiments with and without organic carbon removal revealed no significant contribution of the organic carbon fraction (0.1%) to the sorption of metoprolol on the in this study investigated sediment. Results of this study will contribute to the development of predictive models for the transport of organic cations in the subsurface.

  8. Single crystal structures of thallium (I) thorium fluorides and crystal chemistry of monovalent tetravalent cation pentafluorides

    Science.gov (United States)

    Oudahmane, Abdelghani; El-Ghozzi, Malika; Jouffret, Laurent; Avignant, Daniel

    2015-12-01

    Two thallium (I) thorium (IV) fluorides, TlTh3F13 and TlThF5 were obtained by solid state synthesis and their crystal structures determined from single crystal X-ray diffraction data recorded at room temperature with an APEX-II CCD diffractometer. TlTh3F13 is orthorhombic, space group Pmc21, with a=8.1801(2) Å, b=7.4479(2) Å, c=8.6375(2) Å, V=526.24(2) Å3, Z=2 and TlThF5 is monoclinic, space group P21/n, with a=8.1128(5) Å, b=7.2250(4) Å, c=8.8493(6) Å, β=116.683(3)°, V=463.46(5) Å3, Z=4. The structure of TlTh3F13 comprises layers of corner and edge-sharing ThF9 polyhedra further linked by chains of trans connected tricapped trigonal prisms ThF9 through corners and edges. The three dimensional thorium frameworks delimits channels parallel to [0 0 1] where the 11-coordinated Tl+ ions are arranged into double columns located in mirror planes of the structure. TlTh3F13 is isotypic with RbTh3F13, RbU3F13 and with one of the two polymorphs of CsTh3F13. The structure of TlThF5 may be regarded as a layer structure built up from the regular succession of 2∞[ M ‧F5 ] - corrugated layers further held by the Tl+ ions along the [1 0 1 ̅] direction. The layers are built up from edge and corner-sharing thorium polyhedra where each (ThF9)5- monocapped square antiprism is connected to five others by sharing three edges and two corners. TlThF5 is isostructural with β-NH4UF5 and with one of the polymorphs of CsThF5. A comparison of the different structural types of MM‧F5 pentafluorides is presented and a diagram of repartition of their structures is given. From the comparison of the Tl structures with their Rb or Cs homologs, where very similar monovalent cation environments are observed it should be concluded to a stereochemically inactivity of the 6s2 lone pair of Tl(I) in both TlTh3F13 and TlThF5, contrary to what is observed in richer Tl(I) content Tl3ThF7 fluorothorate.

  9. Monovalent Cation Doping of CH3NH3PbI3 for Efficient Perovskite Solar Cells.

    Science.gov (United States)

    Abdi-Jalebi, Mojtaba; Dar, M Ibrahim; Sadhanala, Aditya; Senanayak, Satyaprasad P; Grätzel, Michael; Friend, Richard H

    2017-03-19

    Here, we demonstrate the incorporation of monovalent cation additives into CH3NH3PbI3 perovskite in order to adjust the optical, excitonic, and electrical properties. The possibility of doping was investigated by adding monovalent cation halides with similar ionic radii to Pb(2+), including Cu(+), Na(+), and Ag(+). A shift in the Fermi level and a remarkable decrease of sub-bandgap optical absorption, along with a lower energetic disorder in the perovskite, was achieved. An order-of-magnitude enhancement in the bulk hole mobility and a significant reduction of transport activation energy within an additive-based perovskite device was attained. The confluence of the aforementioned improved properties in the presence of these cations led to an enhancement in the photovoltaic parameters of the perovskite solar cell. An increase of 70 mV in open circuit voltage for AgI and a 2 mA/cm(2) improvement in photocurrent density for NaI- and CuBr-based solar cells were achieved compared to the pristine device. Our work paves the way for further improvements in the optoelectronic quality of CH3NH3PbI3 perovskite and subsequent devices. It highlights a new avenue for investigations on the role of dopant impurities in crystallization and controls the electronic defect density in perovskite structures.

  10. Effect of primycin on monovalent cation transport of erythrocyte membrane and lipid bilayer.

    Science.gov (United States)

    Blaskó, K; Györgyi, S; Horváth, I

    1979-04-01

    The effects of primycin were investigated on the alkali-cation transport of human erythrocytes and on the electric conduction of bimolecular lipid membranes. In the concentration range of 3.10(-6) approximately 10(-5) M primycin increased the permeability of erythrocytes to alkali-cations according to the sequences Cs+ greater than Rb+ approximately K+ greater than Na+, while the conductance of the negatively charged phosphatidylserine bimolecular lipid membrane increased by 2 approximately 3 orders of magnitude. The resistance-lowering effect of primycin strongly depended on the cationic species applied and a selectivity order Na+ greater than K+ greater than Rb+ greater than Cs+ was found. A possible mechanism of the primycin-membrane interaction is suggested on the basis of experimental data.

  11. A Thermodynamic Model of Monovalent Cation Homeostasis in the Yeast Saccharomyces cerevisiae.

    Directory of Open Access Journals (Sweden)

    Susanne Gerber

    2016-01-01

    Full Text Available Cationic and heavy metal toxicity is involved in a substantial number of diseases in mammals and crop plants. Therefore, the understanding of tightly regulated transporter activities, as well as conceiving the interplay of regulatory mechanisms, is of substantial interest. A generalized thermodynamic description is developed for the complex interplay of the plasma membrane ion transporters, membrane potential and the consumption of energy for maintaining and restoring specific intracellular cation concentrations. This concept is applied to the homeostasis of cation concentrations in the yeast cells of S. cerevisiae. The thermodynamic approach allows to model passive ion fluxes driven by the electrochemical potential differences, but also primary or secondary active transport processes driven by the inter- play of different ions (symport, antiport or by ATP consumption (ATPases. The model-confronted with experimental data-reproduces the experimentally observed potassium and proton fluxes induced by the external stimuli KCl and glucose. The estimated phenomenological constants combine kinetic parameters and transport coefficients. These are in good agreement with the biological understanding of the transporters thus providing a better understanding of the control exerted by the coupled fluxes. The model predicts the flux of additional ion species, like e.g. chloride, as a potential candidate for counterbalancing positive charges. Furthermore, the effect of a second KCl stimulus is simulated, predicting a reduced cellular response for cells that were first exposed to a high KCl stimulus compared to cells pretreated with a mild KCl stimulus. By describing the generalized forces that are responsible for a given flow, the model provides information and suggestions for new experiments. Furthermore, it can be extended to other systems such as e.g. Candida albicans, or selected plant cells.

  12. A Thermodynamic Model of Monovalent Cation Homeostasis in the Yeast Saccharomyces cerevisiae.

    Science.gov (United States)

    Gerber, Susanne; Fröhlich, Martina; Lichtenberg-Fraté, Hella; Shabala, Sergey; Shabala, Lana; Klipp, Edda

    2016-01-01

    Cationic and heavy metal toxicity is involved in a substantial number of diseases in mammals and crop plants. Therefore, the understanding of tightly regulated transporter activities, as well as conceiving the interplay of regulatory mechanisms, is of substantial interest. A generalized thermodynamic description is developed for the complex interplay of the plasma membrane ion transporters, membrane potential and the consumption of energy for maintaining and restoring specific intracellular cation concentrations. This concept is applied to the homeostasis of cation concentrations in the yeast cells of S. cerevisiae. The thermodynamic approach allows to model passive ion fluxes driven by the electrochemical potential differences, but also primary or secondary active transport processes driven by the inter- play of different ions (symport, antiport) or by ATP consumption (ATPases). The model-confronted with experimental data-reproduces the experimentally observed potassium and proton fluxes induced by the external stimuli KCl and glucose. The estimated phenomenological constants combine kinetic parameters and transport coefficients. These are in good agreement with the biological understanding of the transporters thus providing a better understanding of the control exerted by the coupled fluxes. The model predicts the flux of additional ion species, like e.g. chloride, as a potential candidate for counterbalancing positive charges. Furthermore, the effect of a second KCl stimulus is simulated, predicting a reduced cellular response for cells that were first exposed to a high KCl stimulus compared to cells pretreated with a mild KCl stimulus. By describing the generalized forces that are responsible for a given flow, the model provides information and suggestions for new experiments. Furthermore, it can be extended to other systems such as e.g. Candida albicans, or selected plant cells.

  13. Ring-Puckering Potential Energy Functions for Trimethylene Sulfide and Its Monovalent Cation.

    Science.gov (United States)

    Chun, Hye Jin; Ocola, Esther J; Laane, Jaan

    2017-04-13

    The spectra and ring-puckering potential energy function for trimethylene sulfide cation (TMS(+)) from vacuum ultraviolet mass-analyzed threshold ionization spectra have recently been reported. To provide an in-depth comparison of the potential function with that of trimethylene sulfide (TMS) itself, we have used ab initio MP2/cc-pVTZ calculations and DFT B3LYP/cc-pVTZ calculations to predict the structures of both TMS and TMS(+) and then used these to calculate coordinate-dependent ring-puckering kinetic energy functions for both species. These kinetic energy functions allowed us to calculate refined potential energy functions of the puckering for both molecules based on the previously published spectra. TMS has an experimental barrier of 271 cm(-1) and energy minima at ring-puckering angles of ±29°. For TMS(+) the barrier is 60 cm(-1) and the energy minima correspond to ring-puckering angles of ±21°. The lower barrier for the cation reflects the smaller amount of angle strain in the ring angles for TMS(+).

  14. Simultaneous Analysis of Monovalent Anions and Cations with a Sub-Microliter Dead-Volume Flow-Through Potentiometric Detector for Ion Chromatography.

    Science.gov (United States)

    Dumanli, Rukiye; Attar, Azade; Erci, Vildan; Isildak, Ibrahim

    2016-04-01

    A microliter dead-volume flow-through cell as a potentiometric detector is described in this article for sensitive, selective and simultaneous detection of common monovalent anions and cations in single column ion chromatography for the first time. The detection cell consisted of less selective anion- and cation-selective composite membrane electrodes together with a solid-state composite matrix reference electrode. The simultaneous separation and sensitive detection of sodium (Na(+)), potassium (K(+)), ammonium (NH4 (+)), chloride (Cl(-)) and nitrate (NO3 (-)) in a single run was achieved by using 98% 1.5 mM MgSO4 and 2% acetonitrile eluent with a mixed-bed ion-exchange separation column without suppressor column system. The separation and simultaneous detection of the anions and cations were completed in 6 min at the eluent flow-rate of 0.8 mL/min. Detection limits, at S/N = 3, were ranged from 0.2 to 1.0 µM for the anions and 0.3 to 3.0 µM for the cations, respectively. The developed method was successfully applied to the simultaneous determination of monovalent anions and cations in several environmental and biological samples.

  15. Yeast Kch1 and Kch2 membrane proteins play a pleiotropic role in membrane potential establishment and monovalent cation homeostasis regulation.

    Science.gov (United States)

    Felcmanova, Kristina; Neveceralova, Petra; Sychrova, Hana; Zimmermannova, Olga

    2017-08-01

    The Kch1 and Kch2 plasma-membrane proteins were identified in Saccharomyces cerevisiae as being essential for the activation of a high-affinity Ca2+ influx system. We searched for Kch proteins roles in the maintenance of cation homeostasis and tested the effect of kch1 and/or kch2 deletions on various physiological parameters. Compared to wild-type, kch1 kch2 mutant cells were smaller, relatively hyperpolarised, grew better under limited K+ conditions and exhibited altered growth in the presence of monovalent cations. The absence of Kch1 and Kch2 did not change the intracellular pH in cells growing at low potassium or the tolerance of cells to divalent cations, high concentration of sorbitol or extreme external pH. The overexpression of KCH1 only increased the intracellular pH in the presence of elevated K+ in media. None of the phenotypes associated with the deletion of KCH1 and KCH2 in wild type were observed in a strain lacking KCH genes and main K+ uptake systems Trk1 and Trk2. The role of the Kch homologue in cation homeostasis was also tested in Candida albicans cells. Our data demonstrate that Kch proteins significantly contribute to the maintenance of optimal cation homeostasis and membrane potential in S. cerevisiae but not in C. albicans. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  16. Regulation of formyl peptide receptor binding to rabbit neutrophil plasma membranes. Use of monovalent cations, guanine nucleotides, and bacterial toxins to discriminate among different states of the receptor

    Energy Technology Data Exchange (ETDEWEB)

    Feltner, D.E.; Marasco, W.A.

    1989-06-01

    The regulation by monovalent cations, guanine nucleotides, and bacterial toxins of (3H)FMLP binding to rabbit neutrophil plasma membranes was studied by using dissociation techniques to identify regulatory effects on separate receptor states. Under conditions of low receptor occupancy (1 nM (3H)FMLP) and in both Na+ and K+ buffers, dissociation is heterogenous, displaying two distinct, statistically significant off rates. (3H)FMLP binding was enhanced by substituting other monovalent cations for Na+. In particular, enhanced binding in the presence of K+ relative to Na+ was caused by additional binding to both rapidly and slowly dissociating receptors. Three receptor dissociation rates, two of which appear to correspond to the two affinity states detected in equilibrium binding studies, were defined by specific GTP and pertussis toxin (PT) treatments. Neither GTP, nor PT or cholera toxins (CT) had an effect on the rate of dissociation of (3H)FMLP from the rapidly dissociating form of the receptor. Both 100 microM GTP and PT treatments increased the percentage of rapidly dissociating receptors, correspondingly decreasing the percentage of slowly dissociating receptors. The observed changes in the rapidly and slowly dissociating receptors after GTP, PT, and CT treatments were caused by an absolute decrease in the amount of binding to the slowly dissociating receptors. However, complete inhibition of slowly dissociating receptor binding by GTP, PT, or both was never observed. Both GTP and PT treatments, but not CT treatment, increased by two-fold the rate of dissociation of 1 nM (3H)FMLP from the slowly dissociating form of the receptor, resulting in a third dissociation rate. Thus, slowly dissociating receptors comprise two different receptor states, a G protein-associated guanine nucleotide and PT-sensitive state and a guanine nucleotide-insensitive state.

  17. Preparation and characterization of monovalent ion selective cation exchange membranes based on sulphonated poly(ether ether ketone)

    NARCIS (Netherlands)

    Balster, J.H.; Krupenko, O.; Krupenko, O.; Punt, Ineke G.M.; Stamatialis, Dimitrios; Wessling, Matthias

    2005-01-01

    This paper analyses the separation properties of various commercial cation exchange membranes (CEMs) and tailor made membranes based on sulphonated poly(ether ether ketone) and poly(ether sulphone) for binary electrolyte solutions containing protons and calcium ions. All membranes are thoroughly

  18. Differential effect of HOE642 on two separate monovalent cation transporters in the human red cell membrane

    DEFF Research Database (Denmark)

    Bernhardt, Ingolf; Weiss, Erwin; Robinson, Hannah C

    2007-01-01

    Residual K(+) fluxes in red blood cells can be stimulated in conditions of low ionic strength. Previous studies have identified both the non-selective, voltage-dependent cation (NSVDC) channel and the K(+)(Na(+))/H(+) exchanger as candidate pathways mediating this effect, although it is possible...... blood cell apoptosis (eryptosis) and disease....

  19. Preparation and characterisation of monovalent ion selective cation exchange membranes based on sulphonated poly(ether ether ketone)

    NARCIS (Netherlands)

    Balster, J.; Krupenko, O.; Punt, I.G.M.; Stamatialis, D.; Wessling, M.

    2005-01-01

    This paper analyses the separation properties of various commercial cation exchange membranes (CEMs) and tailor made membranes based on sulphonated poly(ether ether ketone) and poly(ether sulphone) for binary electrolyte solutions containing protons and calcium ions. All membranes are thoroughly cha

  20. A monovalent ion-selective cation current activated by noradrenaline in smooth muscle cells of rabbit ear artery.

    Science.gov (United States)

    Wang, Q; Hogg, R C; Large, W A

    1993-04-01

    Membrane currents were recorded with the perforated-patch method with a low-chloride (35 mM) pipette solution in isolated smooth muscle cells of the rabbit ear artery. At a holding potential of -50 mV in potassium-free conditions spontaneous inward single-channel currents were observed and noradrenaline evoked a noisy inward current, which appeared to be comprised of the spontaneous currents. The reversal potential (Vr) of the spontaneous channel and noradrenaline-induced current was not affected in anion-substitution experiments but Vr was altered when external Na+ was replaced with choline or TRIS. The relationship between clamp potential and spontaneous single-channel current amplitude was linear and the mean unitary conductance was 28 pS. Caffeine, which releases calcium from the sarcoplasmic reticulum, and the calcium ionophore ionomycin activated the cation current and also blocked the response to noradrenaline. Spontaneous channel current activity and the noradrenaline-induced current were blocked when external NaCl was replaced with 89 mM CaCl2. The response to noradrenaline was blocked by prazosin but was not affected by yohimbine and therefore the response is mediated by alpha 1-adrenoceptors. It is concluded that in rabbit ear artery smooth muscle cells there is a calcium-activated cation channel of 28 pS conductance, which is relatively impermeable to calcium but can be activated by noradrenaline.

  1. Influence of monovalent alkaline metal cations on binder-free nano-zeolite X in para-xylene separation

    Institute of Scientific and Technical Information of China (English)

    Milad Rasouli; Nakisa Yaghobi; Hossein Atashi; Majid Rasouli

    2015-01-01

    The adsorption process was studied for separating para-xylene from xylene mixture on modified nano-zeolite X in a breakthrough system. Nano-zeolitic adsorbent with different ratios of SiO2/Al2O3 was synthesized through hydrothermal process and ion-exchanged with alkaline metal cations like lithium, sodium and potassium. The product was characterized by X-ray diffraction, scanning electron microscopy (SEM), nitrogen adsorption, transform electron microscopy (TEM) and in situ Fourier transform infrared (FTIR) spectroscopy. The influence of nano-zeolite water content and desorbent type on the selectivity of para-xylene toward other C8 aromatic isomers was studied. The optimization of adsorption process was also investigated under variable operation conditions. The isotherm for each isomer of C8 aromatics and the desorbents possess the adsorption characteristics of Langmuir type. The selectivity factor of para-xylene relative to each of meta-xylene, ortho-xylene and ethylben-zene under the optimum conditions obtained to be 5.36, 2.43 and 3.22, in the order given.

  2. Stable isotope (C, O) and monovalent cation fractionation upon synthesis of carbonate-bearing hydroxyl apatite (CHAP) via calcite transformation

    Science.gov (United States)

    Böttcher, Michael E.; Schmiedinger, Iris; Wacker, Ulrike; Conrad, Anika C.; Grathoff, Georg; Schmidt, Burkhard; Bahlo, Rainer; Gehlken, Peer-L.; Fiebig, Jens

    2016-04-01

    Carbonate-bearing hydroxyl-apatite (CHAP) is of fundamental and applied interest to the (bio)geochemical, paleontological, medical and material science communities, since it forms the basic mineral phase in human and animal teeth and bones. In addition, it is found in non-biogenic phosphate deposits. The stable isotope and foreign element composition of biogenic CHAP is widely used to estimate the formation conditions. This requires careful experimental calibration under well-defined boundary conditions. Within the DFG project EXCALIBOR, synthesis of carbonate-bearing hydroxyapatite was conducted via the transformation of synthetic calcite powder in aqueous solution as a function of time, pH, and temperature using batch-type experiments. The aqueous solution was analyzed for the carbon isotope composition of dissolved inorganic carbonate (gas irmMS), the oxygen isotope composition of water (LCRDS), and the cationic composition. The solid was characterized by powder X-ray diffraction, micro Raman and FTIR spectroscopy, SEM-EDX, elemental analysis (EA, ICP-OES) and gas irmMS. Temperature was found to significantly impact the transformation rate of calcite to CHAP. Upon complete transformation, CHAP was found to contain up to 5% dwt carbonate, depending on the solution composition (e.g., pH), both incorporated on the A and B type position of the crystal lattice. The oxygen isotope fractionation between water and CHAP decreased with increasing temperature with a tentative slope shallower than those reported in the literature for apatite, calcite or aragonite. In addition, the presence of dissolved NH4+, K+ or Na+ in aqueous solution led to partial incorporation into the CHAP lattice. How these distortions of the crystal lattice may impact stable isotope discrimination is subject of future investigations.

  3. Cloning and identification of Group 1 mrp operon encoding a novel monovalent cation/proton antiporter system from the moderate halophile Halomonas zhaodongensis.

    Science.gov (United States)

    Meng, Lin; Hong, Shan; Liu, Henan; Huang, Haipeng; Sun, Hao; Xu, Tong; Jiang, Juquan

    2014-11-01

    The novel species Halomonas zhaodongensis NEAU-ST10-25(T) recently identified by our group is a moderate halophile which can grow at the range of 0-2.5 M NaCl (optimum 0.5 M) and pH 6-12 (optimum pH 9). To explore its halo-alkaline tolerant mechanism, genomic DNA was screened from NEAU-ST10-25(T) in this study for Na(+)(Li(+))/H(+) antiporter genes by selection in Escherichia coli KNabc lacking three major Na(+)(Li(+))/H(+) antiporters. One mrp operon could confer tolerance of E. coli KNabc to 0.8 M NaCl and 100 mM LiCl, and an alkaline pH. This operon was previously mainly designated mrp (also mnh, pha or sha) due to its multiple resistance and pH-related activity. Here, we will also use mrp to designate the homolog from H. zhaodongensis (Hz_mrp). Sequence analysis and protein alignment showed that Hz_mrp should belong to Group 1 mrp operons. Further phylogenetic analysis reveals that Hz_Mrp system should represent a novel sub-class of Group 1 Mrp systems. This was confirmed by a significant difference in pH-dependent activity profile or the specificity and affinity for the transported monovalent cations between Hz_Mrp system and all the known Mrp systems. Therefore, we propose that Hz_Mrp should be categorized as a novel Group 1 Mrp system.

  4. Effects of monovalent cation doping on the structure, microstructure, lattice distortion and magnetic behavior of single crystalline NdMnO3 compounds.

    Science.gov (United States)

    Nandy, Anshuman; Pradhan, S K

    2015-10-21

    Pure and 15 mol% Na, K-doped NdMnO3 compounds with perovskite structures are prepared by sol-gel method. Tiny single crystals are formed after sintering the compounds at 1000 °C. The effect of Na and K doping as well as the effect of sintering temperature on the formation and microstructure of NdMnO3 are studied in detail by the Rietveld refinement technique using X-ray powder diffraction data. Single phase formation and single crystalline growth are also confirmed by high resolution transmission electron microscopy (HRTEM). Bond angles and bond lengths are calculated and shown by 3D diagrams. Monovalent doping induces noticeable changes in the microstructure and yields better structural stability in these compounds. Doping results in the change of Mn-O, Nd-O and Mn-O-Mn bond lengths which in turn reduces the lattice and octahedral distortion in the system along with an increase in the tolerance factor. The magnetic properties of these compounds are also modified as a result of doping. The temperature dependent magnetization results show that the Neel temperature of antiferromagnetic NdMnO3 compound is 67.2 K and the Curie temperatures of ferromagnetic Nd0.85Na0.15MnO3 and Nd0.85K0.15MnO3 compounds are 99.1 K and 98.6 K respectively. Both 15% Na and K doping results in a similar TC in doped NdMnO3 compounds.

  5. An RNA aptamer possessing a novel monovalent cation-mediated fold inhibits lysozyme catalysis by inhibiting the binding of long natural substrates.

    Science.gov (United States)

    Padlan, Camille S; Malashkevich, Vladimir N; Almo, Steve C; Levy, Matthew; Brenowitz, Michael; Girvin, Mark E

    2014-04-01

    RNA aptamers are being developed as inhibitors of macromolecular and cellular function, diagnostic tools, and potential therapeutics. Our understanding of the physical nature of this emerging class of nucleic acid-protein complexes is limited; few atomic resolution structures have been reported for aptamers bound to their protein target. Guided by chemical mapping, we systematically minimized an RNA aptamer (Lys1) selected against hen egg white lysozyme. The resultant 59-nucleotide compact aptamer (Lys1.2minE) retains nanomolar binding affinity and the ability to inhibit lysozyme's catalytic activity. Our 2.0-Å crystal structure of the aptamer-protein complex reveals a helical stem stabilizing two loops to form a protein binding platform that binds lysozyme distal to the catalytic cleft. This structure along with complementary solution analyses illuminate a novel protein-nucleic acid interface; (1) only 410 Å(2) of solvent accessible surface are buried by aptamer binding; (2) an unusually small fraction (∼18%) of the RNA-protein interaction is electrostatic, consistent with the limited protein phosphate backbone contacts observed in the structure; (3) a single Na(+) stabilizes the loops that constitute the protein-binding platform, and consistent with this observation, Lys1.2minE-lysozyme complex formation takes up rather than displaces cations at low ionic strength; (4) Lys1.2minE inhibits catalysis of large cell wall substrates but not catalysis of small model substrates; and (5) the helical stem of Lys1.2minE can be shortened to four base pairs (Lys1.2minF) without compromising binding affinity, yielding a 45-nucleotide aptamer whose structure may be an adaptable protein binding platform.

  6. The Geometry and Structural Properties of the 4,8,12-Trioxa-4,8,12,12c-tetrahydrodibenzo[cd,mn]pyrene System in the Cationic State. Structures of a Planar Organic Cation with Various Monovalent- and Divalent Anions

    DEFF Research Database (Denmark)

    Krebs, Frederik C; Laursen, Bo W.; Johannsen, Ib

    1999-01-01

    The geometry of the 4,8,12-trioxa-4,8,12,12c- tetrahydrodibenzo[cd,mn]pyrene system in the cationic state was established by X-ray structural resolution of the salts formed between the cationand various anions. The geometry was found to be planar for the 4,8,12-trioxa-4,8,12,12c- tetrahydrodibenzo...... [cd,mn]pyrenylium and 2,6,10-tri (tert-butyl)-4,8,12-trioxa-4,8,12,12c-tetrahydrodibenzo[cd,mn]pyre nylium cations with the monovalentanions I-, BF4-, PF6- AsF6-, HNO3. NO3- and CF3SO3-, and the divalent anions S2O62- and Mo6Cl142-. The salts were found to crystallize in distinct space groups...... following a characteristic pattern. Mixed cation-anion stacking resulted in space groups with high symmetry: Pbca in three cases and R (3) over bar c in one; a temperature study of the latter was made at ten different temperatures. The formation of dimers of anions and cations resulted in lower...

  7. Pesticides

    Science.gov (United States)

    ... different kinds of pesticides include insecticides, rodenticides, and herbicides, to name a few. Top of Page How ... in Forensic Toxicology 2017 Forensic Course Abstracts Faculty Bios 2015 ACMT Seminars In Forensic Toxicology 2015 Forensic ...

  8. Pesticides

    Science.gov (United States)

    ... outdoors on rainy or windy days. DO NOT water your garden after using a pesticide. Check the manufacturer's instructions ... home: DO NOT place food scraps in the garden for birds, raccoons, ... puddles of water as soon as possible, change birdbath water at ...

  9. Selective removal of arsenic and monovalent ions from brackish water reverse osmosis concentrate.

    Science.gov (United States)

    Xu, Pei; Capito, Marissa; Cath, Tzahi Y

    2013-09-15

    Concentrate disposal and management is a considerable challenge for the implementation of desalination technologies, especially for inland applications where concentrate disposal options are limited. This study has focused on selective removal of arsenic and monovalent ions from brackish groundwater reverse osmosis (RO) concentrate for beneficial use and safe environmental disposal using in situ and pre-formed hydrous ferric oxides/hydroxides adsorption, and electrodialysis (ED) with monovalent permselective membranes. Coagulation with ferric salts is highly efficient at removing arsenic from RO concentrate to meet a drinking water standard of 10 μg/L. The chemical demand for ferric chloride however is much lower than ferric sulfate as coagulant. An alternative method using ferric sludge from surface water treatment plant is demonstrated as an efficient adsorbent to remove arsenic from RO concentrate, providing a promising low cost, "waste treat waste" approach. The monovalent permselective anion exchange membranes exhibit high selectivity in removing monovalent anions over di- and multi-valent anions. The transport of sulfate and phosphate through the anion exchange membranes was negligible over a broad range of electrical current density. However, the transport of divalent cations such as calcium and magnesium increases through monovalent permselective cation exchange membranes with increasing current density. Higher overall salt concentration reduction is achieved around limiting current density while higher normalized salt removal rate in terms of mass of salt per membrane area and applied energy is attained at lower current density because the energy unitization efficiency decreases at higher current density.

  10. Attraction between like-charged monovalent ions

    Science.gov (United States)

    Zangi, Ronen

    2012-05-01

    Ions with like-charges repel each other with a magnitude given by the Coulomb law. The repulsion is also known to persist in aqueous solutions albeit factored by the medium's dielectric constant. In this paper, we report results from molecular dynamics simulations of alkali halides salt solutions indicating an effective attraction between some of the like-charged monovalent ions. The attraction is observed between anions, as well as between cations, leading to the formation of dimers with lifetimes on the order of few picoseconds. Two mechanisms have been identified to drive this counterintuitive attraction. The first is exhibited by high-charge density ions, such as fluoride, at low salt concentrations, yielding effective attractions with magnitude up to the order of 1-2 kT. In this case, the stronger local electric field generated when the two ions are in contact augments the alignment of neighboring waters toward the ions. This results in a gain of substantial favorable ion-water interaction energy. For fluorides, this interaction constitutes the major change among the different energy components compensating for the anion-anion repulsion, and therefore, rendering like-charge association possible. The second mechanism involves mediation by counterions, the attractions increase with salt concentration and are characterized by small magnitudes. In particular, clusters of ion triplets, in which a counterion is either bridging the two like-charged ions or is paired to only one of them, are formed. Although these two mechanisms may not yield net attractions in many cases, they might still be operational and significant, explaining effective repulsions between like-charged ions with magnitudes much smaller than expected based on continuum electrostatics.

  11. Attraction between like-charged monovalent ions.

    Science.gov (United States)

    Zangi, Ronen

    2012-05-14

    Ions with like-charges repel each other with a magnitude given by the Coulomb law. The repulsion is also known to persist in aqueous solutions albeit factored by the medium's dielectric constant. In this paper, we report results from molecular dynamics simulations of alkali halides salt solutions indicating an effective attraction between some of the like-charged monovalent ions. The attraction is observed between anions, as well as between cations, leading to the formation of dimers with lifetimes on the order of few picoseconds. Two mechanisms have been identified to drive this counterintuitive attraction. The first is exhibited by high-charge density ions, such as fluoride, at low salt concentrations, yielding effective attractions with magnitude up to the order of 1-2 kT. In this case, the stronger local electric field generated when the two ions are in contact augments the alignment of neighboring waters toward the ions. This results in a gain of substantial favorable ion-water interaction energy. For fluorides, this interaction constitutes the major change among the different energy components compensating for the anion-anion repulsion, and therefore, rendering like-charge association possible. The second mechanism involves mediation by counterions, the attractions increase with salt concentration and are characterized by small magnitudes. In particular, clusters of ion triplets, in which a counterion is either bridging the two like-charged ions or is paired to only one of them, are formed. Although these two mechanisms may not yield net attractions in many cases, they might still be operational and significant, explaining effective repulsions between like-charged ions with magnitudes much smaller than expected based on continuum electrostatics.

  12. Monovalent plasmonic nanoparticles for biological applications

    Science.gov (United States)

    Seo, Daeha; Lee, Hyunjung; Lee, Jung-uk; Haas, Thomas J.; Jun, Young-wook

    2016-03-01

    The multivalent nature of commercial nanoparticle imaging agents and the difficulties associated with producing monovalent nanoparticles challenge their use in biology, where clustering of target biomolecules can perturb dynamics of biomolecular targets. Here, we report production and purification of monovalent gold and silver nanoparticles for their single molecule imaging application. We first synthesized DNA-conjugated 20 nm and 40 nm gold and silver nanoparticles via conventional metal-thiol chemistry, yielding nanoparticles with mixed valency. By employing an anion-exchange high performance liquid chromatography (AE-HPLC) method, we purified monovalent nanoparticles from the mixtures. To allow efficient peak-separation resolution while keeping the excellent colloidal stability of nanoparticles against harsh purification condition (e.g. high NaCl), we optimized surface properties of nanoparticles by modulating surface functional groups. We characterized the monovalent character of the purified nanoparticles by hybridizing two complementary conjugates, forming dimers. Finally, we demonstrate the use of the monovalent plasmonic nanoprobes as single molecule imaging probes by tracking single TrkA receptors diffusing on the cell membrane and compare to monovalent quantum dot probes.

  13. Cold gelation of alginates induced by monovalent cations.

    Science.gov (United States)

    Karakasyan, C; Legros, M; Lack, S; Brunel, F; Maingault, P; Ducouret, G; Hourdet, D

    2010-11-08

    A new reversible gelation pathway is described for alginates in aqueous media. From various samples differing by their mannuronic/guluronic content (M/G), both enthalpic and viscoelastic experiments demonstrate that alginates having a high M content are able to form thermoreversible assemblies in the presence of potassium salts. The aggregation behavior is driven by the low solubility of M-blocks at low temperature and high ionic strength. In semidilute solutions, responsive assemblies induce a strong increase of the viscosity below a critical temperature. A true physical gel is obtained in the entangled regime, although the length scale of specific interactions between M-blocks decreases with increasing density of entanglements. Cold setting takes place at low temperatures, below 0 °C for potassium concentrations lower than 0.2 mol/kg, but the aggregation process can be easily shifted to higher temperatures by increasing the salt concentration. The self-assembling process of alginates in solution of potassium salts is characterized by a sharp gelation exotherm and a broad melting endotherm with a large hysteresis of 20-30 °C between the transition temperatures. The viscoelastic properties of alginate gels in potassium salts closely depend on thermal treatment (rate of cooling, time, and temperature of storage), polymer and salt concentrations, and monomer composition as well. In the case of alginates with a high G content, a similar aggregation behavior is also evidenced at higher salt concentrations, but the extent of the self-assembling process remains too weak to develop a true gelation behavior in solution.

  14. Divalent cation shrinks DNA but inhibits its compaction with trivalent cation

    Science.gov (United States)

    Tongu, Chika; Kenmotsu, Takahiro; Yoshikawa, Yuko; Zinchenko, Anatoly; Chen, Ning; Yoshikawa, Kenichi

    2016-05-01

    Our observation reveals the effects of divalent and trivalent cations on the higher-order structure of giant DNA (T4 DNA 166 kbp) by fluorescence microscopy. It was found that divalent cations, Mg(2+) and Ca(2+), inhibit DNA compaction induced by a trivalent cation, spermidine (SPD(3+)). On the other hand, in the absence of SPD(3+), divalent cations cause the shrinkage of DNA. As the control experiment, we have confirmed the minimum effect of monovalent cation, Na(+) on the DNA higher-order structure. We interpret the competition between 2+ and 3+ cations in terms of the change in the translational entropy of the counterions. For the compaction with SPD(3+), we consider the increase in translational entropy due to the ion-exchange of the intrinsic monovalent cations condensing on a highly charged polyelectrolyte, double-stranded DNA, by the 3+ cations. In contrast, the presence of 2+ cation decreases the gain of entropy contribution by the ion-exchange between monovalent and 3+ ions.

  15. Electron transport through monovalent atomic wires

    DEFF Research Database (Denmark)

    Lee, Y. J.; Brandbyge, Mads; Puska, M. J.

    2004-01-01

    Using a first-principles density-functional method we model electron transport through linear chains of monovalent atoms between two bulk electrodes. For noble-metal chains the transport resembles that for free electrons over a potential barrier whereas for alkali-metal chains resonance states...... at the chain determine the conductance. As a result, the conductance for noble-metal chains is close to one quantum of conductance, and it oscillates moderately so that an even number of chain atoms yields a higher value than an odd number. The conductance oscillations are large for alkali-metal chains...

  16. Production and targeting of monovalent quantum dots.

    Science.gov (United States)

    Seo, Daeha; Farlow, Justin; Southard, Kade; Jun, Young-Wook; Gartner, Zev J

    2014-10-23

    The multivalent nature of commercial quantum dots (QDs) and the difficulties associated with producing monovalent dots have limited their applications in biology, where clustering and the spatial organization of biomolecules is often the object of study. We describe here a protocol to produce monovalent quantum dots (mQDs) that can be accomplished in most biological research laboratories via a simple mixing of CdSe/ZnS core/shell QDs with phosphorothioate DNA (ptDNA) of defined length. After a single ptDNA strand has wrapped the QD, additional strands are excluded from the surface. Production of mQDs in this manner can be accomplished at small and large scale, with commercial reagents, and in minimal steps. These mQDs can be specifically directed to biological targets by hybridization to a complementary single stranded targeting DNA. We demonstrate the use of these mQDs as imaging probes by labeling SNAP-tagged Notch receptors on live mammalian cells, targeted by mQDs bearing a benzylguanine moiety.

  17. Monovalent copper-activated oxygenated insulators

    Science.gov (United States)

    Parent, C.; Boutinaud, P.; Flem, G. Le; Moine, B.; Pedrini, C.; Garcia, D.; Faucher, M.

    1994-12-01

    The photoluminescence of monovalent copper in oxygenated insulators has been extensively studied. The spectroscopy and the excited states dynamics of Cu + ions were investigated as a function of the copper concentration and temperature in various glassy and crystallized materials, essentially borates and phosphates. The broad band fluorescences observed in the visible range under UV excitation arise from two main emitting centers: isolated Cu + ions and (Cu +) 2 pairs. The spectroscopic characteristics of isolated Cu + depend strongly on the local structure, whereas those of the copper pairs remain nearly unaltered whatever the host-matrix. Energy diagrams are proposed for both centers, using ab initio LCAO calculations, in connection with structural investigations involving XRD, ND and EXAFS spectroscopies. Borate glasses can be considered as potential laser sources for tunable output in the whole visible range.

  18. Effects of monovalent and divalent salts on the phospholipid and fatty acid compositions of a halotolerant Planococcus sp.

    Science.gov (United States)

    Miller, K J

    1986-09-01

    The phospholipid headgroup and fatty acid compositions of a halotolerant Planococcus sp. (strain A4a) were examined when cells were grown in the presence of high concentrations of a variety of salts. The fatty acid composition of Planococcus sp. strain A4a was altered primarily as a function of the osmolality of the growth medium. The phospholipid headgroup composition was influenced by both the osmolality of the growth medium and the nature of the cation species present. An increase in the cardiolipin/phosphatidylglycerol molar ratio was detected when cells were grown in the presence of high concentrations of monovalent cations.

  19. Hydration of cations: a key to understanding of specific cation effects on aggregation behaviors of PEO-PPO-PEO triblock copolymers.

    Science.gov (United States)

    Lutter, Jacob C; Wu, Tsung-yu; Zhang, Yanjie

    2013-09-05

    This work reports results from the interactions of a series of monovalent and divalent cations with a triblock copolymer, poly(ethylene oxide)-b-poly(propylene oxide)-b-poly(ethylene oxide) (PEO-PPO-PEO). Phase transition temperatures of the polymer in the presence of chloride salts with six monovalent and eight divalent cations were measured using an automated melting point apparatus. The polymer undergoes a two-step phase transition, consisting of micellization of the polymer followed by aggregation of the micelles, in the presence of all the salts studied herein. The results suggest that hydration of cations plays a key role in determining the interactions between the cations and the polymer. The modulation of the phase transition temperature of the polymer by cations can be explained as a balance between three interactions: direct binding of cations to the oxygen in the polymer chains, cations sharing one water molecule with the polymer in their hydration layer, and cations interacting with the polymer via two water molecules. Monovalent cations Na(+), K(+), Rb(+), and Cs(+) do not bind to the polymer, while Li(+) and NH4(+) and all the divalent cations investigated including Mg(2+), Ca(2+), Sr(2+), Ba(2+), Co(2+), Ni(2+), Cu(2+), and Cd(2+) bind to the polymer. The effects of the cations correlate well with their hydration thermodynamic properties. Mechanisms for cation-polymer interactions are discussed.

  20. Synthetic cation-selective nanotube: Permeant cations chaperoned by anions

    Science.gov (United States)

    Hilder, Tamsyn A.; Gordon, Dan; Chung, Shin-Ho

    2011-01-01

    The ability to design ion-selective, synthetic nanotubes which mimic biological ion channels may have significant implications for the future treatment of bacteria, diseases, and as ultrasensitive biosensors. We present the design of a synthetic nanotube made from carbon atoms that selectively allows monovalent cations to move across and rejects all anions. The cation-selective nanotube mimics some of the salient properties of biological ion channels. Before practical nanodevices are successfully fabricated it is vital that proof-of-concept computational studies are performed. With this in mind we use molecular and stochastic dynamics simulations to characterize the dynamics of ion permeation across a single-walled (10, 10), 36 Å long, carbon nanotube terminated with carboxylic acid with an effective radius of 5.08 Å. Although cations encounter a high energy barrier of 7 kT, its height is drastically reduced by a chloride ion in the nanotube. The presence of a chloride ion near the pore entrance thus enables a cation to enter the pore and, once in the pore, it is chaperoned by the resident counterion across the narrow pore. The moment the chaperoned cation transits the pore, the counterion moves back to the entrance to ferry another ion. The synthetic nanotube has a high sodium conductance of 124 pS and shows linear current-voltage and current-concentration profiles. The cation-anion selectivity ratio ranges from 8 to 25, depending on the ionic concentrations in the reservoirs.

  1. Poisson-Helmholtz-Boltzmann model of the electric double layer: analysis of monovalent ionic mixtures.

    Science.gov (United States)

    Bohinc, Klemen; Shrestha, Ahis; Brumen, Milan; May, Sylvio

    2012-03-01

    In the classical mean-field description of the electric double layer, known as the Poisson-Boltzmann model, ions interact exclusively through their Coulomb potential. Ion specificity can arise through solvent-mediated, nonelectrostatic interactions between ions. We employ the Yukawa pair potential to model the presence of nonelectrostatic interactions. The combination of Yukawa and Coulomb potential on the mean-field level leads to the Poisson-Helmholtz-Boltzmann model, which employs two auxiliary potentials: one electrostatic and the other nonelectrostatic. In the present work we apply the Poisson-Helmholtz-Boltzmann model to ionic mixtures, consisting of monovalent cations and anions that exhibit different Yukawa interaction strengths. As a specific example we consider a single charged surface in contact with a symmetric monovalent electrolyte. From the minimization of the mean-field free energy we derive the Poisson-Boltzmann and Helmholtz-Boltzmann equations. These nonlinear equations can be solved analytically in the weak perturbation limit. This together with numerical solutions in the nonlinear regime suggests an intricate interplay between electrostatic and nonelectrostatic interactions. The structure and free energy of the electric double layer depends sensitively on the Yukawa interaction strengths between the different ion types and on the nonelectrostatic interactions of the mobile ions with the surface.

  2. Polyelectrolyte-like behaviour of poly(ethylene-oxide) solutions with added monovalent salt

    Science.gov (United States)

    Lal, Jyotsana; Hakem, Ilhem-Faiza

    2004-03-01

    Solvent effects on the conformation of poly(ethylene-oxide) (PEO) and complexation of PEO by monovalent cations, have been examined by using small-angle neutron scattering. In methanol and acetonitrile, a big change in interchain interaction, osmotic compressibility and local chain conformation have been observed upon addition of small amounts of potassium iodide. The amplitude of the total intensity decreases significantly and a peak at a certain value of the wavevector q* appears as signature of a polyelectrolyte-like behaviour. With further addition of salt, the ionic strength of the solution increases and potassium binding becomes less favorable: the binding constant decreases with the ionic strength and PEO behaves as a neutral polymer with excluded volume. No association between PEO and potassium iodide was observed in aqueous solutions. Reference: I.F. Hakem and J. Lal. Europhysics letters, 64 (2), 204, 2003

  3. Multivalent Protein Assembly Using Monovalent Self-Assembling Building Blocks

    Directory of Open Access Journals (Sweden)

    Katja Petkau-Milroy

    2013-10-01

    Full Text Available Discotic molecules, which self-assemble in water into columnar supramolecular polymers, emerged as an alternative platform for the organization of proteins. Here, a monovalent discotic decorated with one single biotin was synthesized to study the self-assembling multivalency of this system in regard to streptavidin. Next to tetravalent streptavidin, monovalent streptavidin was used to study the protein assembly along the supramolecular polymer in detail without the interference of cross-linking. Upon self-assembly of the monovalent biotinylated discotics, multivalent proteins can be assembled along the supramolecular polymer. The concentration of discotics, which influences the length of the final polymers at the same time dictates the amount of assembled proteins.

  4. Dressed counterions: Polyvalent and monovalent ions at charged dielectric interfaces

    Science.gov (United States)

    Kanduč, Matej; Naji, Ali; Forsman, Jan; Podgornik, Rudolf

    2011-07-01

    We investigate the ion distribution and overcharging at charged interfaces with dielectric inhomogeneities in the presence of asymmetric electrolytes containing polyvalent and monovalent ions. We formulate an effective “dressed counterion” approach by integrating out the monovalent salt degrees of freedom and show that it agrees with results of explicit Monte Carlo simulations. We then apply the dressed counterion approach within the framework of the generalized strong-coupling theory, valid for polyvalent ions at low concentrations, which enables an analytical description for salt effects as well as dielectric inhomogeneities in the limit of strong Coulomb interactions. Limitations and applicability of this theory are examined by comparing the results with simulations.

  5. Actinide cation-cation complexes

    Energy Technology Data Exchange (ETDEWEB)

    Stoyer, Nancy Jane [Univ. of California, Berkeley, CA (United States)

    1994-12-01

    The +5 oxidation state of U, Np, Pu, and Am is a linear dioxo cation (AnO2+) with a formal charge of +1. These cations form complexes with a variety of other cations, including actinide cations. Other oxidation states of actinides do not form these cation-cation complexes with any cation other than AnO2+; therefore, cation-cation complexes indicate something unique about AnO2+ cations compared to actinide cations in general. The first cation-cation complex, NpO2+•UO22+, was reported by Sullivan, Hindman, and Zielen in 1961. Of the four actinides that form AnO2+ species, the cation-cation complexes of NpO2+ have been studied most extensively while the other actinides have not. The only PuO2+ cation-cation complexes that have been studied are with Fe3+ and Cr3+ and neither one has had its equilibrium constant measured. Actinides have small molar absorptivities and cation-cation complexes have small equilibrium constants; therefore, to overcome these obstacles a sensitive technique is required. Spectroscopic techniques are used most often to study cation-cation complexes. Laser-Induced Photacoustic Spectroscopy equilibrium constants for the complexes NpO2+•UO22+, NpO2+•Th4+, PuO2+•UO22+, and PuO2+•Th4+ at an ionic strength of 6 M using LIPAS are 2.4 ± 0.2, 1.8 ± 0.9, 2.2 ± 1.5, and ~0.8 M-1.

  6. Antimicrobial Pesticides

    Science.gov (United States)

    Jump to main content US EPA United States Environmental Protection Agency Search Search Pesticides Share Facebook Twitter Google+ ... of antimicrobial pesticides (Part 158W) Antimicrobials play an important role in public health and safety. While providing ...

  7. Competitive interaction of monovalent cations with DNA from 3D-RISM

    OpenAIRE

    Giambaşu, George M.; Gebala, Magdalena K.; Panteva, Maria T.; Luchko, Tyler; Case, David A.; York, Darrin M.

    2015-01-01

    The composition of the ion atmosphere surrounding nucleic acids affects their folding, condensation and binding to other molecules. It is thus of fundamental importance to gain predictive insight into the formation of the ion atmosphere and thermodynamic consequences when varying ionic conditions. An early step toward this goal is to benchmark computational models against quantitative experimental measurements. Herein, we test the ability of the three dimensional reference interaction site mo...

  8. Polarized spectral complexes of optical functions of monovalent mercury iodide

    Science.gov (United States)

    Sobolev, V. V.; Sobolev, V. Val.; Anisimov, D. V.

    2015-12-01

    Spectral complexes of optical functions of monovalent mercury iodide Hg2I2 were determined for E ⊥ c and E || c polarizations in the range from 2 to 5.5 eV at 4.2 K. The permittivity and characteristic electron energy loss spectra were expanded in simple components with the determination of their main parameters, including the energy of the maximum and the oscillator strength. The calculations were performed based on known reflectance spectra. Computer programs based on Kramers-Kronig relations and the improved parameter-free method of Argand diagrams were used.

  9. Effects of Hofmeister salt series on gluten network formation: Part I. Cation series.

    Science.gov (United States)

    Tuhumury, H C D; Small, D M; Day, L

    2016-12-01

    Different cationic salts were used to investigate the effects of the Hofmeister salt series on gluten network formation. The effects of cationic salts on wheat flour dough mixing properties, the rheological and the chemical properties of the gluten extracted from the dough with different respective salts, were investigated. The specific influence of different cationic salts on the gluten structure formation during dough mixing, compared to the sodium ion, were determined. The effects of different cations on dough and gluten of different flours mostly followed the Hofmeister series (NH4(+), K(+), Na(+), Mg(2+) and Ca(2+)). The impacts of cations on gluten structure and dough rheology at levels tested were relatively small. Therefore, the replacement of sodium from a technological standpoint is possible, particularly by monovalent cations such as NH4(+), or K(+). However the levels of replacement need to take into account sensory attributes of the cationic salts.

  10. Effect of initial ion positions on the interactions of monovalent and divalent ions with a DNA duplex as revealed with atomistic molecular dynamics simulations.

    Science.gov (United States)

    Robbins, Timothy J; Wang, Yongmei

    2013-01-01

    Monovalent (Na(+)) and divalent (Mg(2+)) ion distributions around the Dickerson-Drew dodecamer were studied by atomistic molecular dynamics (MD) simulations with AMBER molecular modeling software. Different initial placements of ions were tried and the resulting effects on the ion distributions around DNA were investigated. For monovalent ions, results were found to be nearly independent of initial cation coordinates. However, Mg(2+) ions demonstrated a strong initial coordinate dependent behavior. While some divalent ions initially placed near the DNA formed essentially permanent direct coordination complexes with electronegative DNA atoms, Mg(2+) ions initially placed further away from the duplex formed a full, nonexchanging, octahedral first solvation shell. These fully solvated cations were still capable of binding with DNA with events lasting up to 20 ns, and in comparison were bound much longer than Na(+) ions. Force field parameters were also investigated with modest and little differences arising from ion (ions94 and ions08) and nucleic acid description (ff99, ff99bsc0, and ff10), respectively. Based on known Mg(2+) ion solvation structure, we conclude that in most cases Mg(2+) ions retain their first solvation shell, making only solvent-mediated contacts with DNA duplex. The proper way to simulate Mg(2+) ions around DNA duplex, therefore, should begin with ions placed in the bulk water.

  11. Metal Cations in G-Quadruplex Folding and Stability

    Science.gov (United States)

    Bhattacharyya, Debmalya; Mirihana Arachchilage, Gayan; Basu, Soumitra

    2016-01-01

    This review is focused on the structural and physicochemical aspects of metal cation coordination to G-Quadruplexes (GQ) and their effects on GQ stability and conformation. G-quadruplex structures are non-canonical secondary structures formed by both DNA and RNA. G-quadruplexes regulate a wide range of important biochemical processes. Besides the sequence requirements, the coordination of monovalent cations in the GQ is essential for its formation and determines the stability and polymorphism of GQ structures. The nature, location, and dynamics of the cation coordination and their impact on the overall GQ stability are dependent on several factors such as the ionic radii, hydration energy, and the bonding strength to the O6 of guanines. The intracellular monovalent cation concentration and the localized ion concentrations determine the formation of GQs and can potentially dictate their regulatory roles. A wide range of biochemical and biophysical studies on an array of GQ enabling sequences have generated at a minimum the knowledge base that allows us to often predict the stability of GQs in the presence of the physiologically relevant metal ions, however, prediction of conformation of such GQs is still out of the realm. PMID:27668212

  12. Metal Cations in G-Quadruplex Folding and Stability

    Science.gov (United States)

    Bhattacharyya, Debmalya; Mirihana Arachchilage, Gayan; Basu, Soumitra

    2016-09-01

    This review is focused on the structural and physico-chemical aspects of metal cation coordination to G-Quadruplexes (GQ) and their effects on GQ stability and conformation. G-Quadruplex structures are non-canonical secondary structures formed by both DNA and RNA. G-quadruplexes regulate a wide range of important biochemical processes. Besides the sequence requirements, the coordination of monovalent cations in the GQ is essential for its formation and determines the stability and polymorphism of GQ structures. The nature, location and dynamics of the cation coordination and their impact on the overall GQ stability are dependent on several factors such as the ionic radii, hydration energy and the bonding strength to the O6 of guanines. The intracellular monovalent cation concentration and the localized ion concentrations determine the formation of GQs and can potentially dictate their regulatory roles. A wide range of biochemical and biophysical studies on an array of GQ enabling sequences have generated at a minimum the knowledge base that allows us to often predict the stability of GQs in presence of the physiologically relevant metal ions, however, prediction of conformation of such GQs is still out of the realm.

  13. Metal Cations in G-Quadruplex Folding and Stability

    Directory of Open Access Journals (Sweden)

    Debmalya Bhattacharyya

    2016-09-01

    Full Text Available This review is focused on the structural and physico-chemical aspects of metal cation coordination to G-Quadruplexes (GQ and their effects on GQ stability and conformation. G-Quadruplex structures are non-canonical secondary structures formed by both DNA and RNA. G-quadruplexes regulate a wide range of important biochemical processes. Besides the sequence requirements, the coordination of monovalent cations in the GQ is essential for its formation and determines the stability and polymorphism of GQ structures. The nature, location and dynamics of the cation coordination and their impact on the overall GQ stability are dependent on several factors such as the ionic radii, hydration energy and the bonding strength to the O6 of guanines. The intracellular monovalent cation concentration and the localized ion concentrations determine the formation of GQs and can potentially dictate their regulatory roles. A wide range of biochemical and biophysical studies on an array of GQ enabling sequences have generated at a minimum the knowledge base that allows us to often predict the stability of GQs in presence of the physiologically relevant metal ions, however, prediction of conformation of such GQs is still out of the realm.

  14. Introduction to Pesticide Labels

    Science.gov (United States)

    Pesticide product labels provide critical information about how to safely and legally handle and use pesticide products. Unlike most other types of product labels, pesticide labels are legally enforceable. Learn about pesticide product labels.

  15. National Pesticide Information Center

    Science.gov (United States)

    ... any pest." Herbicides Disinfectants Fungicides Insecticides Natural and Biological Pesticides Repellents Rodenticides Other types of pesticides Local Contacts Find local pesticide & pest control information Pesticide Information and Resources: Frequently Asked Questions: ...

  16. Competitive Effects of 2+ and 3+ Cations on DNA Compaction

    CERN Document Server

    Tongu, C; Yoshikawa, Y; Zinchenko, A A; Chen, N; Yoshikawa, K

    2016-01-01

    By using single-DNA observation with fluorescence microscopy, we observed the effects of divalent and trivalent cations on the higher-order structure of giant DNA (T4 DNA with 166 kbp). It was found that divalent cations, such as Mg(2+) and Ca(2+), inhibit DNA compaction induced by a trivalent cation, spermidine (SPD(3+)). On the other hand, in the absence of SPD(3+), divalent cations cause the shrinkage of DNA. These experimental observations are inconsistent with the well-established Debye-Huckel scheme regarding the shielding effect of counter ions, which is given as the additivity of contributions of cations with different valences. We interpreted the competition between 2+ and 3+ cations in terms of the change in the translational entropy of the counter ions before and after the folding transition of DNA. For the compaction with SPD(3+), we considered the increase in translational entropy due to the ion-exchange of the intrinsic monovalent cations condensing on a highly-charged polyelectrolyte, double-st...

  17. Obsolete pesticides

    Science.gov (United States)

    Showstack, Randy

    Several hundred tons of obsolete pesticide stocks worldwide will pose a threat to humans and the environment until the year 2030 in some regions, unless funding for waste disposal is significantly increased, the United Nations Food and Agriculture Organization (FAO) said in a message directed to donor governments and industry on May 24.“Deadly chemicals are contaminating the soils, groundwater, irrigation, and drinking water,” said Amemayehu Wodageneh, senior expert on obsolete pesticides for FAO. “These ‘forgotten’ stocks are a serious risk, [and] they could cause an environmental tragedy in rural areas and big cities. There is hardly any developing country that is not affected by the hazards of obsolete pesticides.”

  18. Neutralizing capacity of a new monovalent anti-Bothrops atrox antivenom: comparison with two commercial antivenoms

    Directory of Open Access Journals (Sweden)

    R. Otero

    1997-03-01

    Full Text Available Three horse-derived antivenoms were tested for their ability to neutralize lethal, hemorrhagic, edema-forming, defibrinating and myotoxic activities induced by the venom of Bothrops atrox from Antioquia and Chocó (Colombia. The following antivenoms were used: a polyvalent (crotaline antivenom produced by Instituto Clodomiro Picado (Costa Rica, b monovalent antibothropic antivenom produced by Instituto Nacional de Salud-INS (Bogotá, and c a new monovalent anti-B. atrox antivenom produced with the venom of B. atrox from Antioquia and Chocó. The three antivenoms neutralized all toxic activities tested albeit with different potencies. The new monovalent anti-B. atrox antivenom showed the highest neutralizing ability against edema-forming and defibrinating effects of B. atrox venom (41 ± 2 and 100 ± 32 µl antivenom/mg venom, respectively, suggesting that it should be useful in the treatment of B. atrox envenomation in Antioquia and Chocó

  19. Predicting 3D Structure, Flexibility, and Stability of RNA Hairpins in Monovalent and Divalent Ion Solutions

    Science.gov (United States)

    Shi, Ya-Zhou; Jin, Lei; Wang, Feng-Hua; Zhu, Xiao-Long; Tan, Zhi-Jie

    2015-01-01

    A full understanding of RNA-mediated biology would require the knowledge of three-dimensional (3D) structures, structural flexibility, and stability of RNAs. To predict RNA 3D structures and stability, we have previously proposed a three-bead coarse-grained predictive model with implicit salt/solvent potentials. In this study, we further develop the model by improving the implicit-salt electrostatic potential and including a sequence-dependent coaxial stacking potential to enable the model to simulate RNA 3D structure folding in divalent/monovalent ion solutions. The model presented here can predict 3D structures of RNA hairpins with bulges/internal loops (RNA hairpins with bulge loops of different lengths at several divalent/monovalent ion conditions. In addition, the model successfully predicts the stability of RNA hairpins with various loops/stems in divalent/monovalent ion solutions. PMID:26682822

  20. The role of aspartate-235 in the binding of cations to an artificial cavity at the radical site of cytochrome c peroxidase.

    OpenAIRE

    Fitzgerald, M. M.; Trester, M. L.; Jensen, G M; McRee, D. E.; Goodin, D B

    1995-01-01

    The activated state of cytochrome c peroxidase, compound ES, contains a cation radical on the Trp-191 side chain. We recently reported that replacing this tryptophan with glycine creates a buried cavity at the active site that contains ordered solvent and that will specifically bind substituted imidazoles in their protonated cationic forms (Fitzgerald MM, Churchill MJ, McRee DE, Goodin DB, 1994, Biochemistry 33:3807-3818). Proposals that a nearby carboxylate, Asp-235, and competing monovalent...

  1. Extraction mechanism of monovalent ion-pairs by polyurethane foams.

    Science.gov (United States)

    Fong, P; Chow, A

    1992-07-01

    The extractability sequence of K(+) approximately Rb(+) > Cs(+) > Na(+) > Li(+) for the extraction with polyether foam suggests that the cation chelation mechanism might be operative. However, the same order was obtained for the extraction with 100% polypropylene oxide polyether foam which does not normally adopt a helical structure to form oxygen-rich cavities as easily or as effectively as polyethylene oxide to accommodate alkali metal ions. This result indicates that a hole-size/cation-diameter relationship may not be required for the high extraction of K(+). The extraction of alkali metal DPAs and hydroxides from methanol demonstrates the importance of the solvent effect. It indicates that the water-structure enforced ion-pairing (WSEIP) is the driving force for extraction of the ion-pairs. The extraction mechanism for ionic species can be described as an ion-pair extraction process. The overall effect of ion-pair formation in water and interaction of the extracted ions with foam appears to determine the extractability of the ions of the extractable ion-pair.

  2. Modeling the Interaction between Integrin-Binding Peptide (RGD) and Rutile Surface: The Effect of Cation Mediation on Asp Adsorption

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Chunya [Harbin Institute of Technology; Skelton, Adam [Vanderbilt University; Chen, Mingjun [Harbin Institute of Technology; Vlcek, Lukas [ORNL; Cummings, Peter T [ORNL

    2012-01-01

    The binding of a negatively charged residue, aspartic acid (Asp) in tripeptide arginine-glycine-aspartic acid, onto a negatively charged hydroxylated rutile (110) surface in aqueous solution, containing divalent (Mg{sup 2+}, Ca{sup 2+}, or Sr{sup 2+}) or monovalent (Na{sup +}, K{sup +}, or Rb{sup +}) cations, was studied by molecular dynamics (MD) simulations. The results indicate that ionic radii and charges will significantly affect the hydration, adsorption geometry, and distance of cations from the rutile surface, thereby regulating the Asp/rutile binding mode. The adsorption strength of monovalent cations on the rutile surface in the order Na{sup +} > K{sup +} > Rb{sup +} shows a 'reverse' lyotropic trend, while the divalent cations on the same surface exhibit a 'regular' lyotropic behavior with decreasing crystallographic radii (the adsorption strength of divalent cations: Sr{sup 2+} > Ca{sup 2+} > Mg{sup 2+}). The Asp side chain in NaCl, KCl, and RbCl solutions remains stably H-bonded to the surface hydroxyls and the inner-sphere adsorbed compensating monovalent cations act as a bridge between the COO{sup -} group and the rutile, helping to 'trap' the negatively charged Asp side chain on the negatively charged surface. In contrast, the mediating divalent cations actively participate in linking the COO{sup -} group to the rutile surface; thus the Asp side chain can remain stably on the rutile (110) surface, even if it is not involved in any hydrogen bonds with the surface hydroxyls. Inner- and outer-sphere geometries are all possible mediation modes for divalent cations in bridging the peptide to the rutile surface.

  3. Mechanism of interaction of monovalent ions with phosphatidylcholine lipid membranes.

    Science.gov (United States)

    Vácha, Robert; Jurkiewicz, Piotr; Petrov, Michal; Berkowitz, Max L; Böckmann, Rainer A; Barucha-Kraszewska, Justyna; Hof, Martin; Jungwirth, Pavel

    2010-07-29

    Interactions of different anions with phospholipid membranes in aqueous salt solutions were investigated by molecular dynamics simulations and fluorescence solvent relaxation measurements. Both approaches indicate that the anion-membrane interaction increases with the size and softness of the anion. Calculations show that iodide exhibits a genuine affinity for the membrane, which is due to its pairing with the choline group and its propensity for the nonpolar region of the acyl chains, the latter being enhanced in polarizable calculations showing that the iodide number density profile is expanded toward the glycerol level. Solvent relaxation measurements using Laurdan confirm the influence of large soft ions on the membrane organization at the glycerol level. In contrast, chloride exhibits a peak at the membrane surface only in the presence of a surface-attracted cation, such as sodium but not potassium, suggesting that this behavior is merely a counterion effect.

  4. Monovalent RIVM meningococcal B OMP vesicle F91 vaccines in toddlers

    NARCIS (Netherlands)

    Lafeber AB; Limpt CJP van; Labadie J; Berbers GAM; Kleijn ED de; Groot R de; Rumke HC; Alphen AJW; Sophia Kinderziekenhuis /; LVO

    2001-01-01

    This report gives the results of a randomised phase-II clinical study into the safety and immunogenicity of a monovalent MenB OMV vaccine expressing P1.7h,4 PorA (MonoMen) in toddlers. Safety and immunogenicity are compared for two types of vaccine that are differently adjuvated (either aluminium ph

  5. Persistence and fate of some organophosphorus pesticides in sea sediments along east coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    Sarkar, A.; SenGupta, R.

    Stability and fate of pesticides, monocrotophos, phosphamidon and DDVP, were studied in sediment samples collected along the east coast of India pH, salinity and exchangeable cations present in sediments exhibited profound influence on stability...

  6. Anion recognition and cation-induced molecular motion in a heteroditopic [2]rotaxane.

    Science.gov (United States)

    Leontiev, Alexandre V; Jemmett, Charlotte A; Beer, Paul D

    2011-01-17

    A heteroditopic [2]rotaxane consisting of a calix[4]diquinone-isophthalamide macrocycle and 3,5-bis-amide pyridinium axle components with the capability of switching between two positional isomers in response to barium cation recognition is synthesised. The anion binding properties of the rotaxane's interlocked cavity together with Na(+) , K(+) , NH(4) (+) and Ba(2+) cation recognition capabilities are elucidated by (1) H NMR and UV-visible spectroscopic titration experiments. Upon binding of Ba(2+) , molecular displacement of the axle's positively charged pyridinium group from the rotaxane's macrocyclic cavity occurs, whereas the monovalent cations Na(+) , K(+) and NH(4) (+) are bound without causing significant co-conformational change. The barium cation induced shuttling motion can be reversed on addition of tetrabutylammonium sulfate.

  7. Pesticide Exposure and Asthma

    OpenAIRE

    Kurt, Burak; Akbaba, Muhsin

    2017-01-01

    Exposureto pesticides can trigger or exacerbate asthma, induce bronchospasm, orincrease bronchial hyperreactivity. Pesticides that inhibit cholinesterase canprovoke bronchospasm through increased cholinergic activity. At high doses,certain pesticides can act as airway irritants. Low levels that areinsufficient to cause acute poisoning can trigger severe reactions in thosewithout a previous diagnosis of asthma. Pesticides linked to asthma, wheezing,and hyperreactive airway disease include: 1. ...

  8. Sorption of the organic cation metoprolol on silica gel from its aqueous solution considering the competition of inorganic cations.

    Science.gov (United States)

    Kutzner, Susann; Schaffer, Mario; Börnick, Hilmar; Licha, Tobias; Worch, Eckhard

    2014-05-01

    Systematic batch experiments with the organic monovalent cation metoprolol as sorbate and the synthetic material silica gel as sorbent were conducted with the aim of characterizing the sorption of organic cations onto charged surfaces. Sorption isotherms for metoprolol (>99% protonated in the tested pH of around 6) in competition with mono- and divalent inorganic cations (Na(+), NH4(+), Ca(2+), and Mg(2+)) were determined in order to assess their influence on cation exchange processes and to identify the role of further sorptive interactions. The obtained sorption isotherms could be described well by an exponential function (Freundlich isotherm model) with consistent exponents (about 0.8). In general, a decreasing sorption of metoprolol with increasing concentrations in inorganic cations was observed. Competing ions of the same valence showed similar effects. A significant sorption affinity of metoprolol with ion type dependent Freundlich coefficients KF,0.77 between 234.42 and 426.58 (L/kg)(0.77) could still be observed even at very high concentrations of competing inorganic cations. Additional column experiments confirm this behavior, which suggests the existence of further relevant interactions beside cation exchange. In subsequent batch experiments, the influence of mixtures with more than one competing ion and the effect of a reduced negative surface charge at a pH below the point of zero charge (pHPZC ≈ 2.5) were also investigated. Finally, the study demonstrates that cation exchange is the most relevant but not the sole mechanism for the sorption of metoprolol on silica gel.

  9. Cations and hydration in catalytic RNA: molecular dynamics of the hepatitis delta virus ribozyme.

    Science.gov (United States)

    Krasovska, Maryna V; Sefcikova, Jana; Réblová, Kamila; Schneider, Bohdan; Walter, Nils G; Sponer, Jirí

    2006-07-15

    The hepatitis delta virus (HDV) ribozyme is an RNA enzyme from the human pathogenic HDV. Cations play a crucial role in self-cleavage of the HDV ribozyme, by promoting both folding and chemistry. Experimental studies have revealed limited but intriguing details on the location and structural and catalytic functions of metal ions. Here, we analyze a total of approximately 200 ns of explicit-solvent molecular dynamics simulations to provide a complementary atomistic view of the binding of monovalent and divalent cations as well as water molecules to reaction precursor and product forms of the HDV ribozyme. Our simulations find that an Mg2+ cation binds stably, by both inner- and outer-sphere contacts, to the electronegative catalytic pocket of the reaction precursor, in a position to potentially support chemistry. In contrast, protonation of the catalytically involved C75 in the precursor or artificial placement of this Mg2+ into the product structure result in its swift expulsion from the active site. These findings are consistent with a concerted reaction mechanism in which C75 and hydrated Mg2+ act as general base and acid, respectively. Monovalent cations bind to the active site and elsewhere assisted by structurally bridging long-residency water molecules, but are generally delocalized.

  10. Pesticide Product Label System

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Pesticide Product Label System (PPLS) provides a collection of pesticide product labels (Adobe PDF format) that have been approved by EPA under Section 3 of the...

  11. Household Products Database: Pesticides

    Science.gov (United States)

    ... Glossary Contact Us More Resources Browse Pesticides Category Pesticides activator algaecide ants ants & roaches ants, roaches aphids ... snakes sow bugs spiders termites termites, carpenter ants/bees ticks tomatoes total vegetation control tree trees trees, ...

  12. Pesticides and Pregnancy

    Science.gov (United States)

    Pesticides and Pregnancy In every pregnancy, a woman starts out with a 3-5% chance of having ... risk. This sheet talks about whether exposure to pesticides may increase the risk for birth defects over ...

  13. Pesticides and honey bees

    OpenAIRE

    Amaro, Pedro; Godinho, Joana

    2012-01-01

    After the analysis of the criterion of toxicological classification (TC) of pesticides to honeybees and of the evolution of TC and of legislation related to the theme, in Portugal, it is demonstrated how the absence of rigor of the Portuguese Pesticide Regulation Authority (AFN) and of the pesticides suppliers contribute to the very high probability of mortality of honeybees by pesticides and finally are presented proposals for the optimization of perspectives to...

  14. Pesticides and Environmental Health

    OpenAIRE

    İlter, Hüseyin; Gökdeniz, Mehmet; Akbaba, Muhsin

    2017-01-01

    Pesticidesare used to prevent, control harmful organisms or to reduce their damage inagriculture. The use of pesticides is still indispensable in order to preventthe negative effects of the agricultural diseases and pests.3,2 million tons inthe world, almost 40 thousand tons of pesticide consumption in Turkey is themost important indicator of this. Pesticides get mixed and transform throughair, water and soil then other living things in these environments. Themovement of a pesticide is affect...

  15. Pesticides and food safety

    OpenAIRE

    Ötegen, Volkan Recai; Akbaba, Muhsin; Nazlıcan, Ersin; Kurt, Burak

    2017-01-01

    Besidesprevention of tropical diseases, pesticides are also used to make agriculturalactivities fertile. But pesticides are potentially harmful to our health andmay be toxic to the immune, reproductive and nervous systems. Afterapplication; pesticide residues consist depending on factors such as plantspecies, time of administration, how it applied. While pesticides make foodsupply sustainable, there are concerns about residues in food that peopleconsume. Therefore food safety concept introduc...

  16. Cationic cellulose nanofibers from waste pulp residues and their nitrate, fluoride, sulphate and phosphate adsorption properties.

    Science.gov (United States)

    Sehaqui, Houssine; Mautner, Andreas; Perez de Larraya, Uxua; Pfenninger, Numa; Tingaut, Philippe; Zimmermann, Tanja

    2016-01-01

    Cationic cellulose nanofibers (CNF) having 3 different contents of positively charged quaternary ammonium groups have been prepared from waste pulp residues according to a water-based modification method involving first the etherification of the pulp with glycidyltrimethylammonium chloride followed by mechanical disintegration. The cationic nanofibers obtained were observed by scanning electron microscopy and the extent of the reaction was evaluated by conductometric titration, ζ-potential measurements, and thermogravimetric analyses. The cationic CNF had a maximum cationic charge content of 1.2mmolg(-1) and positive ζ-potential at various pH values. Sorption of negatively charged contaminants (fluoride, nitrate, phosphate and sulphate ions) and their selectivity onto cationic CNF have been evaluated. Maximum sorption of ∼0.6mmolg(-1) of these ions by CNF was achieved and selectivity adsorption studies showed that cationic CNF are more selective toward multivalent ions (PO4(3-) and SO4(2-)) than monovalent ions (F(-) and NO3(-)). In addition, we demonstrated that cationic CNF can be manufactured into permeable membranes capable of dynamic nitrate adsorption by utilizing a simple paper-making process.

  17. Quantitative mapping of intracellular cations in the human amniotic membrane

    Science.gov (United States)

    Moretto, Ph.; Llabador, Y.; Simonoff, M.; Razafindrabe, L.; Bara, M.; Guiet-Bara, A.

    1993-05-01

    The effect of magnesium and taurine on the permeability of cell membranes to monovalent cations has been investigated using the Bordeaux nuclear microprobe. PIXE and RBS techniques have been used to provide quantitative measurements and ion distributions in the isolated amniotic membrane. This physiological model for cellular exchanges allowed us to reveal the distribution of most elements involved in cellular pathways and the modifications under different experimental conditions of incubation in physiological fluids. The PIXE microanalysis provided an original viewpoint on these mechanisms. Following this first study, the amnion compact lamina was found to play a role which was not, up to now, taken into account in the interpretation of electrophysiological experimentations. The release of some ionic species, such as K +, from the epithelial cells, during immersion in isotonic fluids, could have been hitherto underestimated.

  18. Dilution thermodynamics of the biologically relevant cation mixtures

    Energy Technology Data Exchange (ETDEWEB)

    Kaczyński, Marek, E-mail: marek.kaczynski@pwr.wroc.pl; Borowik, Tomasz, E-mail: office@novel-id.pl; Przybyło, Magda, E-mail: magdalena.przybylo@pwr.wroc.pl; Langner, Marek, E-mail: marek.langner@pwr.wroc.pl

    2014-01-10

    Graphical abstract: - Highlights: • Dilution energetics of Ca{sup 2+} can be altered by the aqueous phase ionic composition. • Dissipated heat upon Ca{sup 2+} dilution is drastically reduced in the K{sup +} presence. • Reduction of the enthalpy change upon Ca{sup 2+} dilution is K{sup +} concentration dependent. • The cooperativity of Ca{sup 2+} hydration might be of great biological relevance providing a thermodynamic argument for the specific ionic composition of the intracellular environment. - Abstract: The ionic composition of intracellular space is rigorously controlled by a variety of processes consuming large quantities of energy. Since the energetic efficiency is an important evolutional criterion, therefore the ion fluxes within the cell should be optimized with respect to the accompanying energy consumption. In the paper we present the experimental evidence that the dilution enthalpies of the biologically relevant ions; i.e. calcium and magnesium depend on the presence of monovalent cations; i.e. sodium and potassium. The heat flow generated during the dilution of ionic mixtures was measured with the isothermal titration calorimetry. When calcium was diluted together with potassium the dilution enthalpy was drastically reduced as the function of the potassium concentration present in the solution. No such effect was observed when the potassium ions were substituted with sodium ones. When the dilution of magnesium was investigated the dependence of the dilution enthalpy on the accompanying monovalent cation was much weaker. In order to interpret experimental evidences the ionic cluster formation is postulated. The specific organization of such cluster should depend on ions charges, sizes and organization of the hydration layers.

  19. Mixed polyvalent-monovalent metal coating for carbon-graphite fibers

    Science.gov (United States)

    Harper-Tervet, J.; Tervet, F. W.; Humphrey, M. F. (Inventor)

    1982-01-01

    An improved coating of gasification catalyst for carbon-graphite fibers is provided comprising a mixture of a polyvalent metal such as calcium and a monovalent metal such as lithium. The addition of lithium provides a lighter coating and a more flexible coating when applied to a coating of a carboxyl containing resin such as polyacrylic acid since it reduces the crosslink density. Furthermore, the presence of lithium provides a glass-like substance during combustion which holds the fiber together resulting in slow, even combustion with much reduced evolution of conductive fragments. The coated fibers are utilized as fiber reinforcement for composites.

  20. Coupled-cluster calculations of properties of Boron atom as a monovalent system

    CERN Document Server

    Gharibnejad, H

    2015-01-01

    We present relativistic coupled-cluster (CC) calculations of energies, magnetic-dipole hyperfine constants, and electric-dipole transition amplitudes for low-lying states of atomic boron. The trivalent boron atom is computationally treated as a monovalent system. We explore performance of the CC method at various approximations. Our most complete treatment involves singles, doubles and the leading valence triples. The calculations are done using several approximations in the coupled-cluster (CC) method. The results are within 0.2-0.4% of the energy benchmarks. The hyperfine constants are reproduced with 1-2% accuracy.

  1. 78 FR 3418 - Pesticides; Draft Guidance for Pesticide Registrants on Web-Distributed Labeling for Pesticide...

    Science.gov (United States)

    2013-01-16

    ... human health and the environment from unintentional misuse of pesticides. Web-distributed labeling would... AGENCY Pesticides; Draft Guidance for Pesticide Registrants on Web- Distributed Labeling for Pesticide... is announcing the availability of and seeking public comment on a draft Pesticide Registration Notice...

  2. Pesticides and oncogenic modulation.

    Science.gov (United States)

    Vakonaki, Elena; Androutsopoulos, Vasilis P; Liesivuori, Jyrki; Tsatsakis, Aristidis M; Spandidos, Demetrios A

    2013-05-10

    Pesticides constitute a diverse class of chemicals used for the protection of agricultural products. Several lines of evidence demonstrate that organochlorine and organophosphate pesticides can cause malignant transformation of cells in in vitro and in vivo models. In the current minireview a comprehensive summary of recent in vitro findings is presented along with data reported from human population studies, regarding the impact of pesticide exposure on activation or dysregulation of oncogenes and tumor suppressor genes. Substantial mechanistic work suggests that pesticides are capable of inducing mutations in oncogenes and increase their transcriptional expression in vitro, whereas human population studies indicate associations between pesticide exposure levels and mutation occurrence in cancer-related genes. Further work is required to fully explore the exact mechanisms by which pesticide exposure affects the integrity and normal function of oncogenes and tumor suppressor genes in human populations.

  3. Serial incorporation of a monovalent GalNAc phosphoramidite unit into hepatocyte-targeting antisense oligonucleotides.

    Science.gov (United States)

    Yamamoto, Tsuyoshi; Sawamura, Motoki; Wada, Fumito; Harada-Shiba, Mariko; Obika, Satoshi

    2016-01-01

    The targeting of abundant hepatic asialoglycoprotein receptors (ASGPR) with trivalent N-acetylgalactosamine (GalNAc) is a reliable strategy for efficiently delivering antisense oligonucleotides (ASOs) to the liver. We here experimentally demonstrate the high systemic potential of the synthetically-accessible, phosphodiester-linked monovalent GalNAc unit when tethered to the 5'-terminus of well-characterised 2',4'-bridged nucleic acid (also known as locked nucleic acid)-modified apolipoprotein B-targeting ASO via a bio-labile linker. Quantitative analysis of the hepatic disposition of the ASOs revealed that phosphodiester is preferable to phosphorothioate as an interunit linkage in terms of ASGPR binding of the GalNAc moiety, as well as the subcellular behavior of the ASO. The flexibility of this monomeric unit was demonstrated by attaching up to 5 GalNAc units in a serial manner and showing that knockdown activity improves as the number of GalNAc units increases. Our study suggests the structural requirements for efficient hepatocellular targeting using monovalent GalNAc and could contribute to a new molecular design for suitably modifying ASO.

  4. [Safety and tolerability of monovalent measles and combined measles, mumps, rubella, and varicella vaccines].

    Science.gov (United States)

    Mentzer, D; Meyer, H; Keller-Stanislawski, B

    2013-09-01

    Although effective monovalent and combined measles vaccines have been available for several decades in Germany, measles outbreaks continue to occur leading to severe cases of measles and even death. Possible reasons for the low acceptance of the measles vaccination are concerns about adverse events and serious complications following vaccination. In this report, we have summarized and assessed all adverse events reported in Germany from 2001 to 2012 after vaccination with monovalent- and combined measles-containing vaccines. A total of 1,696 suspected adverse reaction reports describing 5,297 adverse events were sent to the Paul Ehrlich Institute (PEI) between 1 January 2001 and 31 December 2012. The calculated mean reporting rate was 5.7 reports per 100,000 vaccine doses released by the PEI. Analysis of the reports indicates that measles-containing vaccines are well tolerated with a constantly low rate of adverse events reported. Compared to the high rate of serious complications following wild-type measles infection, the benefit of measles-containing vaccines clearly outweighs the anticipated risks of adverse events.

  5. Predicting 3D structure, flexibility and stability of RNA hairpins in monovalent and divalent ion solutions

    CERN Document Server

    Shi, Ya-Zhou; Wang, Feng-Hua; Zhu, Xiao-Long; Tan, Zhi-Jie

    2015-01-01

    A full understanding of RNA-mediated biology would require the knowledge of three-dimensional (3D) structures, structural flexibility and stability of RNAs. To predict RNA 3D structures and stability, we have previously proposed a three-bead coarse-grained predictive model with implicit salt/solvent potentials. In this study, we will further develop the model by improving the implicit-salt electrostatic potential and involving a sequence-dependent coaxial stacking potential to enable the model to simulate RNA 3D structure folding in divalent/monovalent ion solutions. As compared with the experimental data, the present model can predict 3D structures of RNA hairpins with bulge/internal loops (<77nt) from their sequences at the corresponding experimental ion conditions with an overall improved accuracy, and the model also makes reliable predictions for the flexibility of RNA hairpins with bulge loops of different length at extensive divalent/monovalent ion conditions. In addition, the model successfully pred...

  6. Control of Pesticides 2000

    DEFF Research Database (Denmark)

    Krongaard, T.; Petersen, K. K.; Christoffersen, C.

    Three different groups of products covered by the pesticide regulation have been included in the 2000 analytical chemical authority control: 1) herbicides containing aclonifen, clopyralid, dicamba, quinoclamine, bromoxynil, ioxynil, simazine, and terbuthylazine. 2) Fungicides containing fenpropidin......, fluazinam, and kresoxim-methyl, and among insecticides containing fenazaquin. Thus, all the eighteen analysed samples of these pesticides complied with the accepted tolerances with respect to content of active ingredients set by the Danish regulation of pesticides. The only product containing buprofezin...

  7. Control of Pesticides 2001

    DEFF Research Database (Denmark)

    Krongaard, T.; Petersen, K. K.; Christoffersen, C.

    The analytical chemical authority control on pesticide products on the Danish market performed in 2001 is reported. Samples of selected groups of pesticides have been collected from the market and analysed to verify whether the actual contents of the respective active ingredients in the products...... comply with the label-claimed content. The tolerance of deviation from the label-claimed content of active ingredient is set by the Danish pesticide regulation. Three different groups of products covered by the pesticide regulation have been included in the 2001 analytical chemical authority control: 1...

  8. Pesticide Product Information System (PPIS)

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Pesticide Product Information System contains information concerning all pesticide products registered in the United States. It includes registrant name and...

  9. Cation-cation interaction in neptunyl(V) compounds

    Energy Technology Data Exchange (ETDEWEB)

    Krot, N.N. [Russian Academy of Sciences, Institute of Physical Chemistry (Russian Federation); Saeki, Masakatsu [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    2003-03-01

    The original manuscript was prepared by Professor N.N. Krot of Institute of Physical Chemistry, Russian Academy of Sciences, in 1997. Saeki tried to translate that into Japanese and to add some new data since 1997. The contents include the whole picture of cation-cation interactions mainly in 5-valence neptunium compounds. Firstly, characteristic structures of neptunium are summarized of the cation-cation bonding in compounds. Secondly, it is mentioned how the cation-cation bonding affects physical and chemical properties of the compounds. Then, characterization-methods for the cation-cation bonding in the compounds are discussed. Finally, the cation-cation interactions in compounds of other actinide-ions are shortly reviewed. (author)

  10. A functionalized fluorescent dendrimer as a pesticide nanocarrier: application in pest control

    Science.gov (United States)

    Liu, Xiaoxia; He, Bicheng; Xu, Zejun; Yin, Meizhen; Yang, Wantai; Zhang, Huaijiang; Cao, Jingjun; Shen, Jie

    2014-12-01

    We report the delivery of a hydrophobic pesticide, thiamethoxam, by water-soluble nanosized cationic dendrimers that contain hydrophobic dendritic polyesters and peripheral amines, demonstrated by DLS, spectral analysis and ITC. The dendrimer-based nanocarrier can efficiently deliver the pesticide into the live cells and largely increase the cytotoxicity of the drug.We report the delivery of a hydrophobic pesticide, thiamethoxam, by water-soluble nanosized cationic dendrimers that contain hydrophobic dendritic polyesters and peripheral amines, demonstrated by DLS, spectral analysis and ITC. The dendrimer-based nanocarrier can efficiently deliver the pesticide into the live cells and largely increase the cytotoxicity of the drug. Electronic supplementary information (ESI) available. See DOI: 10.1039/c4nr05733c

  11. Safe Disposal of Pesticides

    Science.gov (United States)

    ... on the pesticide label. Check with your local solid waste management authority, environmental agency or health department to find ... of your phone book under categories such as solid waste, public works, or garbage, ... containers. Pesticide residues can contaminate the new contents and cause serious ...

  12. Neurotoxicity of pesticides.

    Science.gov (United States)

    Keifer, Matthew C; Firestone, Jordan

    2007-01-01

    Several pesticides such as organophosphates, carbamates and the organochlorine pesticides directly target nervous tissue as their mechanism of toxicity. In several others, such as the fumigants, the nervous system is affected by toxicological mechanisms that diffusely affect most or all tissues in the body. Both the central and peripheral nervous system are involved in the acute toxidromes of many pesticides resulting in acute short-term effects. There is strong human epidemiological evidence for persistent nervous system damage following acute intoxication with several important pesticide groups such as organophosphates and certain fumigants. However, whether persistent nervous system damage follows chronic low-level exposure to pesticides in adults (particularly organophosphpates), and whether in utero and/or early childhood exposure leads to persistent nervous system damage, is a subject of study at present. Parkinson's Disease, one of the most common chronic central nervous system diseases, has been linked to pesticide exposure in some studies, but other studies have failed to find an association. Several new pesticidal chemicals such as the neo-nicotinoids and fipronil have central nervous system effects, but only case reports are available to date on acute human intoxications with several of these. Little data are yet available on whether long-term effects result from these chemicals. Several ongoing or recently completed studies should add valuable insight into the effects of pesticides on the human nervous system particularly the effect of low-dose, chronic exposure both in adults and children.

  13. Pesticide Sector Performed Well

    Institute of Scientific and Technical Information of China (English)

    Wang Lvxian

    2007-01-01

    @@ 1 Further output growth in the first half of 2007 According to data from the National Bureau of Statistics of China, the output of pesticides (usually refering to pure pesticide technical) in China was 856 thousand tons in the first half of 2007, an increase of 25.6% over the same period of 2006.

  14. Food and Pesticides

    Science.gov (United States)

    EPA sets limits on how much of a pesticide may be used on food during growing and processing, and how much can remain on the food you buy. Learn about regulation of pesticides on food and how you can limit exposure.

  15. Pesticides in Ground Water

    DEFF Research Database (Denmark)

    Bjerg, Poul Løgstrup

    1996-01-01

    Review af: Jack E. Barbash & Elizabeth A. Resek (1996). Pesticides in Ground Water. Distribution trends and governing factors. Ann Arbor Press, Inc. Chelsea, Michigan. pp 588.......Review af: Jack E. Barbash & Elizabeth A. Resek (1996). Pesticides in Ground Water. Distribution trends and governing factors. Ann Arbor Press, Inc. Chelsea, Michigan. pp 588....

  16. Pesticides in Ground Water

    DEFF Research Database (Denmark)

    Bjerg, Poul Løgstrup

    1996-01-01

    Review af: Jack E. Barbash & Elizabeth A. Resek (1996). Pesticides in Ground Water. Distribution trends and governing factors. Ann Arbor Press, Inc. Chelsea, Michigan. pp 588.......Review af: Jack E. Barbash & Elizabeth A. Resek (1996). Pesticides in Ground Water. Distribution trends and governing factors. Ann Arbor Press, Inc. Chelsea, Michigan. pp 588....

  17. Control of Pesticides 2001

    DEFF Research Database (Denmark)

    Krongaard, T.; Petersen, K. K.; Christoffersen, C.

    The analytical chemical authority control on pesticide products on the Danish market performed in 2001 is reported. Samples of selected groups of pesticides have been collected from the market and analysed to verify whether the actual contents of the respective active ingredients in the products...... comply with the label-claimed content. The tolerance of deviation from the label-claimed content of active ingredient is set by the Danish pesticide regulation. Three different groups of products covered by the pesticide regulation have been included in the 2001 analytical chemical authority control: 1....... Satisfactory results were found among herbicides containing pendimethalin and methabenzthiazuron, among fungicides containing azaconazole, tolylfluanid, propamocarb and cyprodinil, and among insecticides containing amitraz, phosalone and diflubenzuron. Thus, the twelve analysed samples of these pesticides...

  18. International collaboration to assess the risk of Guillain Barre Syndrome following Influenza A (H1N1) 2009 monovalent vaccines

    NARCIS (Netherlands)

    Dodd, Caitlin N.; Romio, Silvana A.; Black, Steven; Vellozzi, Claudia; Andrews, Nick; Sturkenboom, Miriam; Zuber, Patrick; Hua, Wei; Bonhoeffer, Jan; Buttery, Jim; Crawford, Nigel; Deceuninck, Genevieve; de Vries, Corinne; De Wals, Philippe; Gutierrez-Gimeno, M. Victoria; Heijbel, Harald; Hughes, Hayley; Hur, Kwan; Hviid, Anders; Kelman, Jeffrey; Kilpi, Tehri; Chuang, S. K.; Macartney, Kristine; Rett, Melisa; Lopez-Callada, Vesta Richardson; Salmon, Daniel; Sanchez, Francisco Gimenez; Sanz, Nuria; Silverman, Barbara; Storsaeter, Jann; Thirugnanam, Umapathi; van der Maas, Nicoline; Yih, Katherine; Zhang, Tao; Izurieta, Hector

    2013-01-01

    Background: The global spread of the 2009 novel pandemic influenza A (H1N1) virus led to the accelerated production and distribution of monovalent 2009 Influenza A (H1N1) vaccines (pH1N1). This pandemic provided the opportunity to evaluate the risk of Guillain-Barre syndrome (GBS), which has been an

  19. In vitro neutralisation of rotavirus infection by two broadly specific recombinant monovalent llama-derived antibody fragments

    NARCIS (Netherlands)

    F. Aladin (Farah); A.W.C. Einerhand (Sandra); J. Bouma (Janneke); S. Bezemer (Sandra); P. Hermans (Pim); D. Wolvers (Danielle); K. Bellamy (Kate); L.G.J. Frenken (Leon); J. Gray (Jim); M. Iturriza-Gómara (Miren)

    2012-01-01

    textabstractRotavirus is the main cause of viral gastroenteritis in young children. Therefore, the development of inexpensive antiviral products for the prevention and/or treatment of rotavirus disease remains a priority. Previously we have shown that a recombinant monovalent antibody fragment (refe

  20. Directed evolution of antibody fragments with monovalent femtomolar antigen-binding affinity.

    Science.gov (United States)

    Boder, E T; Midelfort, K S; Wittrup, K D

    2000-09-26

    Single-chain antibody mutants have been evolved in vitro with antigen-binding equilibrium dissociation constant K(d) = 48 fM and slower dissociation kinetics (half-time > 5 days) than those for the streptavidin-biotin complex. These mutants possess the highest monovalent ligand-binding affinity yet reported for an engineered protein by over two orders of magnitude. Optimal kinetic screening of randomly mutagenized libraries of 10(5)-10(7) yeast surface-displayed antibodies enabled a >1,000-fold decrease in the rate of dissociation after four cycles of affinity mutagenesis and screening. The consensus mutations are generally nonconservative by comparison with naturally occurring mouse Fv sequences and with residues that do not contact the fluorescein antigen in the wild-type complex. The existence of these mutants demonstrates that the antibody Fv architecture is not intrinsically responsible for an antigen-binding affinity ceiling during in vivo affinity maturation.

  1. The interactions between cationic cellulose and Gemini surfactant in aqueous solution.

    Science.gov (United States)

    Zhao, Shaojing; Cheng, Fa; Chen, Yu; Wei, Yuping

    2016-05-05

    Due to the extensive application of cationic cellulose in cosmetic, drug delivery and gene therapy, combining the improvement effect of surfactant-cellulose complexes, to investigate the properties of cellulose in aqueous solution is an important topic from both scientific and technical views. In this study, the phase behavior, solution properties and microstructure of Gemini surfactant sodium 5-nonyl-2-(4-(4-nonyl-2-sulfonatophenoxy)butoxy)phenyl sulfite (9-4-9)/cationic cellulose (JR400, the ammonium groups are directly bonded to the hydroxyethyl substituent with a degree substitution of 0.37) mixture was investigated using turbidity, fluorescence spectrophotometer and shear rheology techniques. As a control, the interaction of corresponding monovalent surfactant, sodium 2-ethoxy-5-nonylbenzenesulfonate (9-2) with JR400 in aqueous solution was also studied. Experimental results showed that 9-4-9/JR400 mixture has lower critical aggregation concentration (CAC) and critical micelle concentration (CMC) (about one order of magnitude) than 9-2/JR400 mixture. A low concentration of Gemini surfactant 9-4-9 appeared to induce an obvious micropolarity and viscosity value variation of the mixture, while these effects required a high concentration of corresponding monovalent one. Furthermore, dynamic light scattering (DLS) and transmission electron microscopy (TEM) measurements illuminated the formation and collapse procedure of network structure of the 9-4-9/JR400 mixture, which resulted in the increase and decrease of viscosity. These results suggest that the molecular structure of the surfactant has a great effect on its interaction with cationic cellulose. Moreover, the Gemini surfactant/cationic cellulose mixture may be used as a potencial stimuli-responsive drug delivery vector which not only load hydrophilic drugs, but also deliver hydrophobic substances.

  2. Monovalent metal ions play an essential role in catalysis and intersubunit communication in the tryptophan synthase bienzyme complex.

    Science.gov (United States)

    Woehl, E U; Dunn, M F

    1995-07-25

    This investigation shows that the alpha 2 beta 2 tryptophan synthase bienzyme complex from Salmonella typhimurium is subject to monovalent metal ion activation. The effects of the monovalent metal ions Na+ and K+ were investigated using rapid scanning stopped-flow (RSSF), single-wavelength stopped-flow (SWSF), and steady-state techniques. RSSF measurements of individual steps in the reaction of L-serine and indole to give L-trytophan (the beta-reaction) as well as the reaction of 3-indole-D-glycerol 3'-phosphate (IGP) with L-serine (the alpha beta-reaction) demonstrate that monovalent metal ions such as Na+ and K+ change the distribution of intermediates in both the transient and steady states. Therefore the metal ion effect alters relative ground-state energies and the relative positions of ground- and transition-state energies. The RSSF spectra and SWSF time courses show that the turnover of indole is significantly reduced in the absence of either Na+ or K+. The alpha-aminoacrylate Schiff base species, E(A-A), is in a less active state in the absence of monovalent metal ions. Na+ decreases the steady-state rate of IGP cleavage (the alpha-reaction) to about 30% of the value obtained in the absence of metal ions. Steady-state investigations show that in the absence of monovalent metal ions the alpha- and alpha beta-reactions have the same activity. Na+ binding gives a 30-fold stimulation of the alpha-reaction when the beta-site is in the E(A-A) form.(ABSTRACT TRUNCATED AT 250 WORDS)

  3. Change Color Effect and Spectral Properties of Gold Nanoparticle-cationic Surfactants System

    Institute of Scientific and Technical Information of China (English)

    JIANG Zhi-liang; PAN Hong-cheng; YUAN Wei-en

    2004-01-01

    The change color effect of gold nanoparticle solutions was studied by means of resonance scattering and absorption spectrometry and scan electron microscopy. The red Au nanoparticles with a size of 10 nm exhibit a resonance absorption peak and a resonance scattering peak all at 525 nm. After some inorganic electrolyte was added to a red Au nanoparticles solution, the color of the solution became blue and the absorbance at 600-700 nm was significantly increased. The ratio of the concentration of monovalent cations, at which the resonance scattering of the system at 525 nm is maximal to that of divalent cations, is in the range of 100 : 1 -100 : 1.8. It is in good agreement with the Schulze-Hardy rule of the coagulation value of electrolyte. After adding some cationic surfactants to the above solution, the color of the solution is in deep blue, with two resonance absorption peaks at 550 and 680 nm, and a greatly enhanced resonance scattering peak at 525 nm.The experiments demonstrate that the stronger the hydrophobicity of the cationic surfactant is, the stronger the change color effect of the Au nanoparticle solution promoted by cationic surfactant is. The change color effect of Au nanoparticle solution is resulted from the increased diameter of Au nanoparticles, and the changes of resonance absorption peak and resonance scattering.

  4. The Danish Pesticide Tax

    DEFF Research Database (Denmark)

    Pedersen, Anders Branth; Nielsen, Helle Ørsted; Andersen, Mikael Skou

    2015-01-01

    This case study analyses the effects of the Danish pesticide tax (1996-2013) on agriculture which was introduced as an ad valorem tax in 1996, doubled in 1998, and redesigned in 2013 as a tax based on the toxicity of the pesticides. The Danish pesticide taxes probably represent the world’s highes...... individuals in the target group necessarily react to the economic incentives as predicted by economic modeling. It also demonstrates that a small first green-tax-step over time might develop into a better tax design.......This case study analyses the effects of the Danish pesticide tax (1996-2013) on agriculture which was introduced as an ad valorem tax in 1996, doubled in 1998, and redesigned in 2013 as a tax based on the toxicity of the pesticides. The Danish pesticide taxes probably represent the world’s highest...... pesticide taxes on agriculture, which makes it interesting to analyze how effective they have been. Here the effects of the ad valorem tax (1996-2013) are analyzed. The case study demonstrates the challenges of choosing an optimal tax design in a complex political setting where, additionally, not all...

  5. Watershed scale influence of pesticide reduction practices on pesticides and fishes within channelized agricultural headwater streams

    Science.gov (United States)

    Implementation of pesticide reduction practices to reduce pesticide usage within agricultural watersheds has the potential to reduce pesticide concentrations within agricultural streams. The watershed scale influence of pesticide reduction practices on pesticides and the biota within agricultural he...

  6. Pesticide Registration Information System

    Data.gov (United States)

    U.S. Environmental Protection Agency — PRISM provides an integrated, web portal for all pesticide related data, communications, registrations and transactions for OPP and its stakeholders, partners and...

  7. Control of Pesticides 2006

    DEFF Research Database (Denmark)

    Krongaard, Teddy; Petersen, Kitty Kastalag; Christoffersen, Christel

    The analytical chemical authority control of pesticide products on the Danish market in 2006 is described in this report. Samples of selected groups of pesticides have been collected from the market and analysed to verify whether the actual contents of the respective active ingredients in the pro......The analytical chemical authority control of pesticide products on the Danish market in 2006 is described in this report. Samples of selected groups of pesticides have been collected from the market and analysed to verify whether the actual contents of the respective active ingredients...... analytical chemical authority control: Herbicides containing metamitron, propaquizafop and haloxyfop-ethoxyethyl. Fungicides containing azoxystrobin, propiconazole, cyprodinil, picoxystrobin and fenpropidin. Insecticides containing pirimicarb. Plant growth regulators containing chlormequat chloride, mepiquat...

  8. Control of Pesticides 2004

    DEFF Research Database (Denmark)

    Krongaard, T.; Petersen, K. K.; Christoffersen, C.

    Four different groups of products covered by the pesticide regulation were included in the 2004 analytical chemical authority control: 1) Herbicides containing bentazone, dicamba, dichlorprop-P, mecoprop-P, MCPA, foramsulfuron, iodosulfuron-methylsodium, rimsulfuron and triasulfuron. 2) Fungicides...

  9. Control of Pesticides 2000

    DEFF Research Database (Denmark)

    Krongaard, T.; Petersen, K. K.; Christoffersen, C.

    Three different groups of products covered by the pesticide regulation have been included in the 2000 analytical chemical authority control: 1) herbicides containing aclonifen, clopyralid, dicamba, quinoclamine, bromoxynil, ioxynil, simazine, and terbuthylazine. 2) Fungicides containing fenpropidin...

  10. Pesticide-Exposure Matrix

    Science.gov (United States)

    The "Pesticide-exposure Matrix" was developed to help epidemiologists and other researchers identify the active ingredients to which people were likely exposed when their homes and gardens were treated for pests in past years.

  11. Control of pesticides 2003

    DEFF Research Database (Denmark)

    Krongaard, T.; Petersen, K. K.; Christoffersen, C.

    Four different groups of products covered by the pesticide regulation were included in the 2003 analytical chemical authority control: 1) Herbicides containing clodinafop- propargyl, clomazone, fluroxypyr and glyphosate. 2) Fungicides containing bitertanol, fuberidazole, fenhexamid and pencycuron...

  12. Control of Pesticides 2004

    DEFF Research Database (Denmark)

    Krongaard, T.; Petersen, K. K.; Christoffersen, C.

    Four different groups of products covered by the pesticide regulation were included in the 2004 analytical chemical authority control: 1) Herbicides containing bentazone, dicamba, dichlorprop-P, mecoprop-P, MCPA, foramsulfuron, iodosulfuron-methylsodium, rimsulfuron and triasulfuron. 2) Fungicides...

  13. Types of Pesticide Ingredients

    Science.gov (United States)

    Pesticide active ingredients are described by the types of pests they control or how they work. For example, algicides kill algae, biopesticides are derived from natural materials, and insecticides kill insects.

  14. Why We Review Pesticides

    Science.gov (United States)

    As required by the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA), EPA periodically reviews existing registered pesticides to ensure they can be used safely, without unreasonable risks to human health and the environment.

  15. Respiratory Protection against Pesticides

    OpenAIRE

    Kurt, Burak; Akbaba, Muhsin

    2015-01-01

    Although the respiratory (breathing) system tolerates exposure to a limited degree, some chemicals can impair or destroy portions of it. For many pesticides, the respiratory system is the quickest and most direct route into the circulatory system, allowing rapid transport throughout the body. Thus, it is important to follow the pesticide label and follow directions for control of exposure, especially when respiratory protection is specified. A respirator is a safety device covering at least t...

  16. Control of Pesticides 2006

    DEFF Research Database (Denmark)

    Krongaard, Teddy; Petersen, Kitty Kastalag; Christoffersen, Christel

    The analytical chemical authority control of pesticide products on the Danish market in 2006 is described in this report. Samples of selected groups of pesticides have been collected from the market and analysed to verify whether the actual contents of the respective active ingredients...... analytical chemical authority control: Herbicides containing metamitron, propaquizafop and haloxyfop-ethoxyethyl. Fungicides containing azoxystrobin, propiconazole, cyprodinil, picoxystrobin and fenpropidin. Insecticides containing pirimicarb. Plant growth regulators containing chlormequat chloride, mepiquat...

  17. [Neurotoxicology of pesticides].

    Science.gov (United States)

    Ichikawa, Hiroo

    2015-01-01

    Pesticides have been used for many years for preventing, destroying, repelling, or mitigating pests such as insects, rodents, and weeds. However, most pesticides are not completely specific for pests and can also induce damage to the human nervous system. In particular, insecticides often directly targets the nervous system by affecting major targets such as the neuro-transmitter metabolism, neuronal receptors, and ion channels; acetylcholine (ACh) esterase for organo-phosphates and carbamates, nicotinic ACh receptor for neonicotinoids, γ-aminobutyric acid receptors/chloride channels for organochlorides and fipronil, and voltage-gated sodium channel for pyrethroids. Additional targets include sites in the sodium channels, glutamate-gated chloride channels, and octopamine and ryanodine receptors. Several pesticides also produce adverse neurological effects indirectly by disrupting the general cellular mechanisms that support the high metabolic activity of the nervous system. Nowadays, more potent pesticides are being developed as replacements for the older, harmful ones. Pesticide neurotoxicity in humans may involve the central or peripheral nervous system or both and may induce typical neuronal damage in case of acute poisoning even by new agents. However, whether effect of exposure to pesticides at below acute-poisoning threshold level remains unclear. Moreover, neurotoxicology for behavioral and higher-brain function remains an unresolved and a challenging problem.

  18. On the real performance of cation exchange resins in wastewater treatment under conditions of cation competition: the case of heavy metal pollution.

    Science.gov (United States)

    Prelot, Benedicte; Ayed, Imen; Marchandeau, Franck; Zajac, Jerzy

    2014-01-01

    Sorption performance of cation-exchange resins Amberlite® IRN77 and Amberlite™ IRN9652 toward Cs(I) and Sr(II) has been tested in single-component aqueous solutions and simulated waste effluents containing other monovalent (Effluent 1) or divalent (Effluent 2) metal cations, as well as nitrate, borate, or carbonate anions. The individual sorption isotherms of each main component were measured by the solution depletion method. The differential molar enthalpy changes accompanying the ion-exchange between Cs+ or Sr2+ ions and protons at the resin surface from single-component nitrate solutions were measured by isothermal titration calorimetry and they showed a higher specificity of the two resins toward cesium. Compared to the retention limits of both resins under such idealized conditions, an important depression in the maximum adsorption capacity toward each main component was observed in multication systems. The overall effect of ion exchange process appeared to be an unpredictable outcome of the individual sorption capacities of the two resins toward various cations as a function of the cation charge, size, and concentration. The cesium retention capacity of the resins was diminished to about 25% of the "ideal" value in Effluent 1 and 50% in Effluent 2; a further decrease to about 15% was observed upon concomitant strontium addition. The uptake of strontium by the resins was found to be less sensitive to the addition of other metal components: the greatest decrease in the amount adsorbed was 60% of the ideal value in the two effluents for Amberlite® IRN77 and 75% for Amberlite™ IRN9652. It was therefore demonstrated that any performance tests carried out under idealized conditions should be exploited with much caution to predict the real performance of cation exchange resins under conditions of cation competition.

  19. Metal-Organic Frameworks (MOFs) as Multivalent Materials: Size Control and Surface Functionalization by Monovalent Capping Ligands.

    Science.gov (United States)

    Rijnaarts, Timon; Mejia-Ariza, Raquel; Egberink, Richard J M; van Roosmalen, Wies; Huskens, Jurriaan

    2015-07-13

    Control over particle size and composition are pivotal to tune the properties of metal organic frameworks (MOFs), for example, for biomedical applications. Particle-size control and functionalization of MIL-88A were achieved by using stoichiometric replacement of a small fraction of the divalent fumarate by monovalent capping ligands. A fluorine-capping ligand was used to quantify the surface coverage of capping ligand at the surface of MIL-88A. Size control at the nanoscale was achieved by using a monovalent carboxylic acid-functionalized poly(ethylene glycol) (PEG-COOH) ligand at different concentrations. Finally, a biotin-carboxylic acid capping ligand was used to functionalize MIL-88A to bind fluorescently labeled streptavidin as an example towards bioapplications. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Does Cation Size Affect Occupancy and Electrostatic Screening of the Nucleic Acid Ion Atmosphere?

    Science.gov (United States)

    Gebala, Magdalena; Bonilla, Steve; Bisaria, Namita; Herschlag, Daniel

    2016-08-31

    Electrostatics are central to all aspects of nucleic acid behavior, including their folding, condensation, and binding to other molecules, and the energetics of these processes are profoundly influenced by the ion atmosphere that surrounds nucleic acids. Given the highly complex and dynamic nature of the ion atmosphere, understanding its properties and effects will require synergy between computational modeling and experiment. Prior computational models and experiments suggest that cation occupancy in the ion atmosphere depends on the size of the cation. However, the computational models have not been independently tested, and the experimentally observed effects were small. Here, we evaluate a computational model of ion size effects by experimentally testing a blind prediction made from that model, and we present additional experimental results that extend our understanding of the ion atmosphere. Giambasu et al. developed and implemented a three-dimensional reference interaction site (3D-RISM) model for monovalent cations surrounding DNA and RNA helices, and this model predicts that Na(+) would outcompete Cs(+) by 1.8-2.1-fold; i.e., with Cs(+) in 2-fold excess of Na(+) the ion atmosphere would contain an equal number of each cation (Nucleic Acids Res. 2015, 43, 8405). However, our ion counting experiments indicate that there is no significant preference for Na(+) over Cs(+). There is an ∼25% preferential occupancy of Li(+) over larger cations in the ion atmosphere but, counter to general expectations from existing models, no size dependence for the other alkali metal ions. Further, we followed the folding of the P4-P6 RNA and showed that differences in folding with different alkali metal ions observed at high concentration arise from cation-anion interactions and not cation size effects. Overall, our results provide a critical test of a computational prediction, fundamental information about ion atmosphere properties, and parameters that will aid in the

  1. Pesticides in drinking water

    Directory of Open Access Journals (Sweden)

    Irena Grmek-Košnik

    2006-09-01

    Full Text Available Background: Use of pesticides deceives of indisputable advantage, however remainders of pesticides in drinking water might represent potential danger for health on foodstuffs. In European Union (EU pesticides and their relevant metabolic, degrading and reactive products, with exception for aldrin, dieldrin, heptaclor and heptaclor epoxide, should not exceed the concentration of 0.10 μg/l. At limit value 0.10 μg/l we wish to achieve null value these substances in drinking water.Methods: In years 2004 and 2005 monitoring of pesticides in drinking waters on pipes of consumers in all larger towns in state was done. Majority of pesticides were analysed by gas chromatography in combination with mass spectrometry while fluid cromatography was used primarily for badly volatile or polar and termolabile compound.Results: Results of analyses of drinking water and of ground waters for years 2004 and 2005 showed that levels of atrazine, desethyl-atrazine and 2.6 dichlorobenzamide were exceeded few times when compared to required levels. In 2005 bentazone, MCPP, metolachlor, terbuthylazin were exceeded. In 2004 concentration of pesticides were exceeded in 25 samples in 15 different areas, supplying 183,881 inhabitants. In 2005 concentration of pesticides were exceeded in 31 samples in 14 different areas, supplying 151,297 inhabitants. The distribution shows, that contamination was present mostly in the northeast part of Slovenia, where intensive agriculture takes place.Conclusions: Received status review acquired by monitoring of pesticides in drinking water is only an assessment of circumstances that will gain in representativity by enlarged number of sampling locations and longer observation time. For assessment of trends of pollution of drinking water in Slovenia it will be necessary to monitor concentration of pesticides through longer period. We could have unpolluted drinking water only with restricted use of pesticides on water-protection ranges or

  2. How accurate is Poisson-Boltzmann theory for monovalent ions near highly charged interfaces?

    Science.gov (United States)

    Bu, Wei; Vaknin, David; Travesset, Alex

    2006-06-20

    Surface sensitive synchrotron X-ray scattering studies were performed to obtain the distribution of monovalent ions next to a highly charged interface. A lipid phosphate (dihexadecyl hydrogen-phosphate) was spread as a monolayer at the air-water interface to control surface charge density. Using anomalous reflectivity off and at the L3 Cs+ resonance, we provide spatial counterion (Cs+) distributions next to the negatively charged interfaces. Five decades in bulk concentrations are investigated, demonstrating that the interfacial distribution is strongly dependent on bulk concentration. We show that this is due to the strong binding constant of hydronium H3O+ to the phosphate group, leading to proton-transfer back to the phosphate group and to a reduced surface charge. The increase of Cs+ concentration modifies the contact value potential, thereby causing proton release. This process effectively modifies surface charge density and enables exploration of ion distributions as a function of effective surface charge-density. The experimentally obtained ion distributions are compared to distributions calculated by Poisson-Boltzmann theory accounting for the variation of surface charge density due to proton release and binding. We also discuss the accuracy of our experimental results in discriminating possible deviations from Poisson-Boltzmann theory.

  3. Differences on the conversion of celestite in solutions bearing monovalent ions under hydrothermal conditions

    Science.gov (United States)

    Rendón-Angeles, J. C.; Pech-Canul, M. I.; López-Cuevas, J.; Matamoros-Veloza, Z.; Yanagisawa, K.

    2006-12-01

    The replacement of SO 42- ions by monovalent ions in mineral SrSO 4 crystals was investigated under hydrothermal conditions by using aqueous solutions bearing F - and OH - ions. Experiments were conducted at various temperatures (150-250 °C) for different reaction intervals (1-96 h), with M-/SO 42- molar ratios of 1, 5 and 10, where M-=F - or OH -. The celestite crystals were completely converted into SrF 2 crystals, at 200 °C using a F -/SO 42- molar ratio=5 for 24 h. The morphology of the converted SrF 2 crystals indicated that the heteroionic conversion proceeded by a pseudomorphic replacement process, because the transformed crystals maintained their original shape and dimensions. In contrast, the SrSO 4 crystals were instantaneously converted into the Sr(OH) 2 phase by a bulk dissolution-recrystallization mechanism, resulting in the formation of large transparent acicular Sr(OH) 2 crystals. The differences on the conversion process are mainly associated with the chemical interaction between the mineral crystal and the hydrothermal fluid. In addition, the chemical stability of the converted phase with low solubility is also essential for the heteroionic conversion to proceed by the pseudomorphic replacement process.

  4. Aqueous batteries based on mixed monovalence metal ions: a new battery family.

    Science.gov (United States)

    Chen, Liang; Zhang, Leyuan; Zhou, Xufeng; Liu, Zhaoping

    2014-08-01

    As existing battery technologies struggle to meet the requirements for widespread use in the field of large-scale energy storage, new concepts are urgently needed to build batteries with high energy density, low cost, and good safety. Here, we demonstrate two new aqueous batteries based on two monovalence metal ions (Li(+) /K(+) and Na(+) /K(+) ) as charge-transfer ions, Ni1 Zn1 HCF/TiP2 O7 and Ni1 Zn1 HCF/NaTi2 (PO4 )3 . These new batteries are unlike the conventional "rocking-chair" aqueous metal-ion batteries based on the migration of one type of shuttle ion between cathode and anode. They can deliver specific energy of 46 Wh kg(-1) and 53 Wh kg(-1) based on the total mass of active materials; this is superior to current aqueous battery systems based on sodium-ion and/or potassium-ion technologies. These two new batteries together with the previously developed Li(+) /Na(+) mixed-ion battery not only constitute a new battery family for energy storage, but also greatly broaden our horizons for battery research.

  5. Potent dengue virus neutralization by a therapeutic antibody with low monovalent affinity requires bivalent engagement.

    Directory of Open Access Journals (Sweden)

    Melissa A Edeling

    2014-04-01

    Full Text Available We recently described our most potently neutralizing monoclonal antibody, E106, which protected against lethal Dengue virus type 1 (DENV-1 infection in mice. To further understand its functional properties, we determined the crystal structure of E106 Fab in complex with domain III (DIII of DENV-1 envelope (E protein to 2.45 Å resolution. Analysis of the complex revealed a small antibody-antigen interface with the epitope on DIII composed of nine residues along the lateral ridge and A-strand regions. Despite strong virus neutralizing activity of E106 IgG at picomolar concentrations, E106 Fab exhibited a ∼20,000-fold decrease in virus neutralization and bound isolated DIII, E, or viral particles with only a micromolar monovalent affinity. In comparison, E106 IgG bound DENV-1 virions with nanomolar avidity. The E106 epitope appears readily accessible on virions, as neutralization was largely temperature-independent. Collectively, our data suggest that E106 neutralizes DENV-1 infection through bivalent engagement of adjacent DIII subunits on a single virion. The isolation of anti-flavivirus antibodies that require bivalent binding to inhibit infection efficiently may be a rare event due to the unique icosahedral arrangement of envelope proteins on the virion surface.

  6. Higher cytotoxicity of divalent antibody-toxins than monovalent antibody-toxins

    Energy Technology Data Exchange (ETDEWEB)

    Won, JaeSeon; Nam, PilWon; Lee, YongChan [College of Life Sciences and Graduate School of Biotechnology, Korea University, 5-ga Anam-dong, Sungbuk-gu, Seoul 136-701 (Korea, Republic of); Choe, MuHyeon, E-mail: choemh@korea.ac.kr [College of Life Sciences and Graduate School of Biotechnology, Korea University, 5-ga Anam-dong, Sungbuk-gu, Seoul 136-701 (Korea, Republic of)

    2009-04-24

    Recombinant antibody-toxins are constructed via the fusion of a 'carcinoma-specific' antibody fragment to a toxin. Due to the high affinity and high selectivity of the antibody fragments, antibody-toxins can bind to surface antigens on cancer cells and kill them without harming normal cells [L.H. Pai, J.K. Batra, D.J. FitzGerald, M.C. Willingham, I. Pastan, Anti-tumor activities of immunotoxins made of monoclonal antibody B3 and various forms of Pseudomonas exotoxin, Proc. Natl. Acad. Sci. USA 88 (1991) 3358-3362]. In this study, we constructed the antibody-toxin, Fab-SWn-PE38, with SWn (n = 3, 6, 9) sequences containing n-time repeated (G{sub 4}S) between the Fab fragment and PE38 (38 kDa truncated form of Pseudomonas exotoxin A). The SWn sequence also harbored one cysteine residue that could form a disulfide bridge between two Fab-SWn-PE38 monomers. We assessed the cytotoxicity of the monovalent (Fab-SWn-PE38), and divalent ([Fab-SWn-PE38]{sub 2}) antibody-toxins. The cytotoxicity of the dimer against the CRL1739 cell line was approximately 18.8-fold higher than that of the monomer on the ng/ml scale, which was approximately 37.6-fold higher on the pM scale. These results strongly indicate that divalency provides higher cytotoxicity for an antibody-toxin.

  7. Antigenic specificity of a monovalent versus polyvalent MOMP based Chlamydia pecorum vaccine in koalas (Phascolarctos cinereus).

    Science.gov (United States)

    Kollipara, Avinash; Wan, Charles; Rawlinson, Galit; Brumm, Jacqui; Nilsson, Karen; Polkinghorne, Adam; Beagley, Kenneth; Timms, Peter

    2013-02-06

    Chlamydia continues to be a major pathogen of koalas. The bacterium is associated with ocular, respiratory and urogenital tract infections and a vaccine is considered the best option to limit the decline of mainland koala populations. Over the last 20 years, efforts to develop a chlamydial vaccine in humans have focussed on the use of the chlamydial major outer membrane protein (MOMP). Potential problems with the use of MOMP-based vaccines relate to the wide range of genetic diversity in its four variable domains. In the present study, we evaluated the immune response of koalas vaccinated with a MOMP-based C. pecorum vaccine formulated with genetically and serologically diverse MOMPs. Animals immunised with individual MOMPs developed strong antibody and lymphocyte proliferation responses to both homologous as well as heterologous MOMP proteins. Importantly, we also showed that vaccine induced antibodies which effectively neutralised various heterologous strains of koala C. pecorum in an in vitro assay. Finally, we also demonstrated that the immune responses in monovalent as well as polyvalent MOMP vaccine groups were able to recognise whole chlamydial elementary bodies, illustrating the feasibility of developing an effective MOMP based C. pecorum vaccine that could protect against a range of strains. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

  8. Impact of universal mass vaccination with monovalent inactivated hepatitis A vaccines – A systematic review

    Science.gov (United States)

    Stuurman, Anke L.; Marano, Cinzia; Bunge, Eveline M.; De Moerlooze, Laurence; Shouval, Daniel

    2017-01-01

    ABSTRACT The WHO recommends integration of universal mass vaccination (UMV) against hepatitis A virus (HAV) in national immunization schedules for children aged ≥1 year, if justified on the basis of acute HAV incidence, declining endemicity from high to intermediate and cost-effectiveness. This recommendation has been implemented in several countries. Our aim was to assess the impact of UMV using monovalent inactivated hepatitis A vaccines on incidence and persistence of anti-HAV (IgG) antibodies in pediatric populations. We conducted a systematic review of literature published between 2000 and 2015 in PubMed, Cochrane Library, LILACS, IBECS identifying a total of 27 studies (Argentina, Belgium, China, Greece, Israel, Panama, the United States and Uruguay). All except one study showed a marked decline in the incidence of hepatitis A post introduction of UMV. The incidence in non-vaccinated age groups decreased as well, suggesting herd immunity but also rising susceptibility. Long-term anti-HAV antibody persistence was documented up to 17 y after a 2-dose primary vaccination. In conclusion, introduction of UMV in countries with intermediate endemicity for HAV infection led to a considerable decrease in the incidence of hepatitis A in vaccinated and in non-vaccinated age groups alike. PMID:27786671

  9. Monovalency Unleashes the Full Therapeutic Potential of the DN-30 Anti-Met Antibody*

    Science.gov (United States)

    Pacchiana, Giovanni; Chiriaco, Cristina; Stella, Maria C.; Petronzelli, Fiorella; De Santis, Rita; Galluzzo, Maria; Carminati, Paolo; Comoglio, Paolo M.; Michieli, Paolo; Vigna, Elisa

    2010-01-01

    Met, the high affinity receptor for hepatocyte growth factor, is one of the most frequently activated tyrosine kinases in human cancer and a validated target for cancer therapy. We previously developed a mouse monoclonal antibody directed against the extracellular portion of Met (DN-30) that induces Met proteolytic cleavage (receptor “shedding”) followed by proteasome-mediated receptor degradation. This translates into inhibition of hepatocyte growth factor/Met-mediated biological activities. However, DN-30 binding to Met also results in partial activation of the Met kinase due to antibody-mediated receptor homodimerization. To safely harness the therapeutic potential of DN-30, its shedding activity must be disassociated from its agonistic activity. Here we show that the DN-30 Fab fragment maintains high affinity Met binding, elicits efficient receptor shedding and down-regulation, and does not promote kinase activation. In Met-addicted tumor cell lines, DN-30 Fab displays potent cytostatic and cytotoxic activity in a dose-dependent fashion. DN-30 Fab also inhibits anchorage-independent growth of several tumor cell lines. In mouse tumorigenesis assays using Met-addicted carcinoma cells, intratumor administration of DN-30 Fab or systemic delivery of a chemically stabilized form of the same molecule results in reduction of Met phosphorylation and inhibition of tumor growth. These data provide proof of concept that monovalency unleashes the full therapeutic potential of the DN-30 antibody and point at DN-30 Fab as a promising tool for Met-targeted therapy. PMID:20833723

  10. Monovalency unleashes the full therapeutic potential of the DN-30 anti-Met antibody.

    Science.gov (United States)

    Pacchiana, Giovanni; Chiriaco, Cristina; Stella, Maria C; Petronzelli, Fiorella; De Santis, Rita; Galluzzo, Maria; Carminati, Paolo; Comoglio, Paolo M; Michieli, Paolo; Vigna, Elisa

    2010-11-12

    Met, the high affinity receptor for hepatocyte growth factor, is one of the most frequently activated tyrosine kinases in human cancer and a validated target for cancer therapy. We previously developed a mouse monoclonal antibody directed against the extracellular portion of Met (DN-30) that induces Met proteolytic cleavage (receptor "shedding") followed by proteasome-mediated receptor degradation. This translates into inhibition of hepatocyte growth factor/Met-mediated biological activities. However, DN-30 binding to Met also results in partial activation of the Met kinase due to antibody-mediated receptor homodimerization. To safely harness the therapeutic potential of DN-30, its shedding activity must be disassociated from its agonistic activity. Here we show that the DN-30 Fab fragment maintains high affinity Met binding, elicits efficient receptor shedding and down-regulation, and does not promote kinase activation. In Met-addicted tumor cell lines, DN-30 Fab displays potent cytostatic and cytotoxic activity in a dose-dependent fashion. DN-30 Fab also inhibits anchorage-independent growth of several tumor cell lines. In mouse tumorigenesis assays using Met-addicted carcinoma cells, intratumor administration of DN-30 Fab or systemic delivery of a chemically stabilized form of the same molecule results in reduction of Met phosphorylation and inhibition of tumor growth. These data provide proof of concept that monovalency unleashes the full therapeutic potential of the DN-30 antibody and point at DN-30 Fab as a promising tool for Met-targeted therapy.

  11. Evolutionary and structural perspectives of plant cyclic nucleotide-gated cation channels

    KAUST Repository

    Zelman, Alice K.

    2012-05-29

    Ligand-gated cation channels are a frequent component of signaling cascades in eukaryotes. Eukaryotes contain numerous diverse gene families encoding ion channels, some of which are shared and some of which are unique to particular kingdoms. Among the many different types are cyclic nucleotide-gated channels (CNGCs). CNGCs are cation channels with varying degrees of ion conduction selectivity. They are implicated in numerous signaling pathways and permit diffusion of divalent and monovalent cations, including Ca2+ and K+. CNGCs are present in both plant and animal cells, typically in the plasma membrane; recent studies have also documented their presence in prokaryotes. All eukaryote CNGC polypeptides have a cyclic nucleotide-binding domain and a calmodulin binding domain as well as a six transmembrane/one pore tertiary structure. This review summarizes existing knowledge about the functional domains present in these cation-conducting channels, and considers the evidence indicating that plant and animal CNGCs evolved separately. Additionally, an amino acid motif that is only found in the phosphate binding cassette and hinge regions of plant CNGCs, and is present in all experimentally confirmed CNGCs but no other channels was identified. This CNGC-specific amino acid motif provides an additional diagnostic tool to identify plant CNGCs, and can increase confidence in the annotation of open reading frames in newly sequenced genomes as putative CNGCs. Conversely, the absence of the motif in some plant sequences currently identified as probable CNGCs may suggest that they are misannotated or protein fragments. 2012 Zelman, Dawe, Gehring and Berkowitz.

  12. Multi-scale simulation studies on interaction between anionic surfactants and cations

    Directory of Open Access Journals (Sweden)

    Siwei Meng

    2014-12-01

    Full Text Available In this paper, a dissipative particle dynamics (DPD simulation method was used to investigate the impact of cations on the rheological properties of dodecyl sulfonate surfactant solutions. In order to obtain reasonable interaction between head groups of the surfactant, the geometric structure and interaction between dodecyl sulfonate and cations are optimized using density function theory (DFT at the B3LYP/6-31G level. The DFT calculated results indicate that α-methylene nearest the head group can be classified as a part of the polar head. After binding, the charge on polar head decreases, thus greatly reduces the repulsion between the head groups. It is found that the presence of counterions is one of induction factors on the formation of wormlike micelles, thus greatly enhances the viscosity of surfactant solution. With the increasing in shear strengthen, the wormlike micelles are gradually oriented in the x direction and then broken up into small spherical micelles. This process is also shown by the decrease of viscosity, which decreases quickly at the low shear rates, then keeps almost a constant at the moderate shear rates and at last decreases again at the shear rates larger than a critical value. Compared with monovalent cations, divalent cations have a stronger effect on the rheological properties of dodecyl sulfonate solutions.

  13. Human Health Benchmarks for Pesticides

    Data.gov (United States)

    U.S. Environmental Protection Agency — Advanced testing methods now allow pesticides to be detected in water at very low levels. These small amounts of pesticides detected in drinking water or source...

  14. Shanghai Pesticide Research Institute (SPRI)

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    @@ Shanghai Pesticide Research Institute (SPRI), established in 1963, is the first professional pesticide institute in China. After being approved by the Science & Technology Committee of PRC, it became the base for Shanghai Branch of National Pesticide R&D South center.

  15. Pesticides: A Community Action Guide.

    Science.gov (United States)

    Bumstead, Cynthia, Ed.; And Others

    Developed to provide an introduction to the issues surrounding the use of chemical pesticides, this booklet encourages individuals and communities to become active in determining the safe use and regulation of pesticides. The major components of the guide include: (1) an explanation of the issue; (2) pesticides and their effect on human health;…

  16. Control of pesticides 2003

    DEFF Research Database (Denmark)

    Krongaard, T.; Petersen, K. K.; Christoffersen, C.

    Four different groups of products covered by the pesticide regulation were included in the 2003 analytical chemical authority control: 1) Herbicides containing clodinafop- propargyl, clomazone, fluroxypyr and glyphosate. 2) Fungicides containing bitertanol, fuberidazole, fenhexamid and pencycuron...... containing methoprene complied with the accepted tolerance limits with respect to the content of the active ingredient as specified in Danish Statutory Order on pesticides. None of the 44 examined samples contained OPEO, but 5 of the samples contained NPEO. Three of these five samples were produced before...

  17. Paralytic poliomyelitis associated with Sabin monovalent and bivalent oral polio vaccines in Hungary.

    Science.gov (United States)

    Estívariz, Concepción F; Molnár, Zsuzsanna; Venczel, Linda; Kapusinszky, Beatrix; Zingeser, James A; Lipskaya, Galina Y; Kew, Olen M; Berencsi, György; Csohán, Agnes

    2011-08-01

    Historical records of patients with vaccine-associated paralytic poliomyelitis (VAPP) in Hungary during 1961-1981 were reviewed to assess the risk of VAPP after oral polio vaccine (OPV) administration. A confirmed VAPP case was defined as a diagnosis of paralytic poliomyelitis and residual paralysis at 60 days in a patient with an epidemiologic link to the vaccine. Archived poliovirus isolates were retested using polymerase chain reaction and sequencing of the viral protein 1 capsid region. This review confirmed 46 of 47 cases previously reported as VAPP. Three cases originally linked to monovalent OPV (mOPV) 3 and one case linked to mOPV1 presented after administration of bivalent OPV 1 + 3 (bOPV). The adjusted VAPP risk per million doses administered was 0.18 for mOPV1 (2 cases/11.13 million doses), 2.96 for mOPV3 (32 cases/10.81 million doses), and 12.82 for bOPV (5 cases/390,000 doses). Absence of protection from immunization with inactivated poliovirus vaccine or exposure to OPV virus from routine immunization and recent injections could explain the higher relative risk of VAPP in Hungarian children. In polio-endemic areas in which mOPV3 and bOPV are needed to achieve eradication, the higher risk of VAPP would be offset by the high risk of paralysis due to wild poliovirus and higher per-dose efficacy of mOPV3 and bOPV compared with trivalent OPV.

  18. Deposition kinetics of extracellular polymeric substances (EPS) on silica in monovalent and divalent salts.

    Science.gov (United States)

    Zhu, Pingting; Long, Guoyu; Ni, Jinren; Tong, Meiping

    2009-08-01

    The deposition kinetics of extracellular polymeric substances (EPS) on silica surfaces were examined in both monovalent and divalent solutions under a variety of environmentally relevant ionic strength and pH conditions by employing a quartz crystal microbalance with dissipation (DCM-D). Soluble EPS (SEPS) and bound EPS (BEPS) were extracted from four bacterial strains with different characteristics. Maximum favorable deposition rates (k(fa)) were observed for all EPS at low ionic strengths in both NaCl and CaCl2 solutions. With the increase of ionic strength, k(fa) decreased due to the simultaneous occurrence of EPS aggregation in solutions. Deposition efficiency (alpha; the ratio of deposition rates obtained under unfavorable versus corresponding favorable conditions) for all EPS increased with increasing ionic strength in both NaCl and CaCl2 solutions, which agreed with the trends of zeta potentials and was consistent with the classic Derjaguin-Landau-Verwey-Overbeek (DLVO) theory. Comparison of alpha for SEPS and BEPS extracted from the same strain showed that the trends of alpha did not totally agree with trends of zeta potentials, indicating the deposition kinetics of EPS on silica surfaces were not only controlled by DLVO interactions, but also non-DLVO forces. Close comparison of alpha for EPS extracted from different sources showed alpha increased with increasing proteins to polysaccharides ratio. Subsequent experiments for EPS extracted from the same strain but with different proteins to polysaccharides ratios and from activated sludge also showed that alpha were largest for EPS with greatest proteins to polysaccharides ratio. Additional experiments for pure protein and solutions with different pure proteins to pure saccharides ratios further corroborated that larger proteins to polysaccharides ratio resulted in greater EPS deposition.

  19. 2011 EPA Pesticide General Permit (PGP)

    Data.gov (United States)

    U.S. Environmental Protection Agency — The 2011 EPA Pesticide General Permit (PGP) covers discharges of biological pesticides, and chemical pesticides that leave a residue, in areas where EPA is the NPDES...

  20. 75 FR 3235 - Pesticide Products; Registration Applications

    Science.gov (United States)

    2010-01-20

    ... AGENCY Pesticide Products; Registration Applications AGENCY: Environmental Protection Agency (EPA). ACTION: Notice. SUMMARY: This notice announces receipt of applications to register pesticide products... Applications EPA received applications as follows to register pesticide products containing active ingredients...

  1. Radiation induced microbial pesticide

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ki Yup; Lee, Young Keun; Kim, Jae Sung; Kim, Jin Kyu; Lee, Sang Jae

    2000-01-01

    To control plant pathogenic fungi, 4 strains of bacteria (K1, K3, K4, YS1) were isolated from mushroom compost and hot spring. K4, K1, K3, YS1 strain showed wide antifungal spectrum and high antifungal activities against 13 kinds of fungi. Mutants of K1 and YS1 strains were induced by gamma-ray radiation and showed promising antifungal activities. These wild type and mutants showed resistant against more than 27 kinds of commercial pesticides among 30 kinds of commercial pesticides test particularly, YS1-1006 mutant strain showed resistant against hydrogen oxide. And mutants had increased antifungal activity against Botryoshaeria dothidea. These results suggested that radiation could be an useful method for the induction of functional mutants. (author)

  2. Bioeconomic Analysis of Pesticide Demand

    OpenAIRE

    Moffitt, L. Joe; Farnsworth, Richard L.

    1981-01-01

    The ability of insects to develop resistance to specific pesticides affects pesticide demand. However, the affect of resistance on demand cannot be observed or measured. This analysis substitutes an expression for the unobserved resistance variable in a pesticide demand model and then illustrates the model's potential by estimating demand for DDT. To arrive at the expression characterizing the unobserved resistance variable a biological resistance model is constructed then incorporated into t...

  3. Pesticide exposure--Egyptian scene.

    Science.gov (United States)

    Mansour, Sameeh A

    2004-05-20

    Pesticides have contributed to dramatic increases in crop yields and in the quantity and variety of the diet. Also, they have helped to limit the spread of certain diseases. But pesticides have harmful effects; they can cause injury to human health as well as to the environment. The range of these adverse health effects includes acute and persistent injury to the nervous system, lung damage, injury to the reproductive organs, dysfunction of the immune and endocrine systems, birth defects, and cancer. Problems associated with pesticide hazards to man and the environment are not confined to the developing countries. Developed nations have already suffered these problems, and still facing some problems in certain locations. For many reasons, the severity of pesticide hazards is much pronounced in Third World Countries. A number of long persistent organochlorines and highly toxic organophosphates, which have been banned or severely restricted, are still marketed and used in many developing countries. The misuse of pesticides by concerned individuals, in addition to lack of or weak national controlling plans are behind the outbreak of adverse effects in developing countries. Since about 25 years, the use of DDT and many other organochlorine pesticides in Egyptian agriculture has been banned. However, these long persistent compounds are still detectable in many different types of environmental samples (e.g., water, fish, sediment, vegetables, fruits, milk, foodstuffs, etc.). Large number of compounds known as "extremely hazardous", "highly hazardous", "probable human carcinogenic", and "possible human carcinogenic", are listed among the pesticides registered and recommended for use in Egypt during the season of 2001/2002. The present article deals with: trends and patterns of pesticide use, impact of pesticides on human health, factors contributing to pesticide risks, environmental impacts of pesticides, and bioaccumulation of pesticide residues in food; giving special

  4. On the selective adsorption of cations in the cell wall of the green alga Valonia utricularis

    Science.gov (United States)

    Kesseler, H.

    1980-06-01

    The selective adsorption of the cations Na+, K+, Mg++ and Ca++ by the cell wall of the Mediterranean alga Valonia utricularis (Siphonocladales, Chlorophyceae) from sea water of 40 %. S was investigated by extraction of cell-wall preparations, eluted before in 1.1 mol methanol (adjusted to pH 8) with 0.1 n formic acid in a Soxhlet apparatus. Na+ and K+ were determined by flame photometry, Mg++ and Ca++ by complexometric titration with EDTA. From calculation of the dry weight:fresh weight ratios and the chloride determinations in the eluates, the Donnan free-space fraction of the total cell-wall volume was calculated to about 35 %, and the analytical results of the cation concentrations in the extracts expressed as μVal cm-3 DFS. This calculation is based on the assumption that the acidic groups of the noncellulosic matrix material, carrying negative charges by dissociation at the reaction of sea water (ph about 8) are responsible for the adsorption of cations by exhibition of a Donnan effect. The results obtained show clearly that besides the divalent cations Mg++ and Ca++, which according to the physico-chemical laws of the Donnan distribution must be relatively accumulated to the second power of the monovalent ones, potassium is also enriched by selective adsorption, and the K+:Na+ ratio increased significantly compared with that in sea water. This seems to indicate that the strength of attraction between the cations and the negative sites is dependent on the radii of the ions and the state of hydration and/or polarisation of the ions and binding sites.

  5. Modelling pesticides residues

    OpenAIRE

    2004-01-01

    This work is a contribution to the development of a specific method to assess the presence of residues in agricultural commodities. The following objectives are formulated: to identify and describe main processes in environment — plant exchanges, to build of a model to assess the residue concentration at harvest in agricultural commodities, to understand the functioning of the modelled system, to characterise pesticides used in field crops and identify optimisation potentials in phytosanitary...

  6. International Activities Related to Pesticides

    Science.gov (United States)

    Regulating pesticides involves many international issues and working with our regulatory partners in other countries. Learn about EPA's activities, upcoming meetings and workshops, and various regulatory issues.

  7. Electronic Submissions of Pesticide Applications

    Science.gov (United States)

    Applications for pesticide registration can be submitted electronically, including forms, studies, and draft product labeling. Applicants need not submit multiple electronic copies of any pieces of their applications.

  8. Mimicking the cell membrane: bio-inspired simultaneous functions with monovalent anion selectivity and antifouling properties of anion exchange membrane

    Science.gov (United States)

    Zhao, Yan; Liu, Huimin; Tang, Kaini; Jin, Yali; Pan, Jiefeng; der Bruggen, Bart Van; Shen, Jiangnan; Gao, Congjie

    2016-11-01

    A new bio-inspired method was applied in this study to simultaneously improve the monovalent anion selectivity and antifouling properties of anion exchange membranes (AEMs). Three-layer architecture was developed by deposition of polydopamine (PDA) and electro-deposition of N-O-sulfonic acid benzyl chitosan (NSBC). The innermost and outermost layers were PDA with different deposition time. The middle layer was prepared by NSBC. Fourier transform infrared spectroscopy and scanning electron microscopy confirmed that PDA and NSBC were successfully modified on the surfaces of AEMs. The contact angle of the membranes indicated an improved hydrophilicity of the modified membranes. A series of electrodialysis experiments in which Cl‑/SO42‑ separation was studied, demonstrating the monovalent anion selectivity of the samples. The Cl‑/SO42‑ permselectivity of the modified membranes can reach up to 2.20, higher than that of the commercial membrane (only 0.78) during 90 minutes in electrodialysis (ED). The increase value of the resistance of the membranes was also measured to evaluate the antifouling properties. Sodium dodecyl benzene sulfonate (SDBS) was used as the fouling material in the ED process and the membrane area resistance of modified membrane increase value of was only 0.08 Ωcm2 30 minutes later.

  9. Investigating the efficacy of monovalent and tetravalent dengue vaccine formulations against DENV-4 challenge in AG129 mice.

    Science.gov (United States)

    Fuchs, Jeremy; Chu, Haiyan; O'Day, Peter; Pyles, Richard; Bourne, Nigel; Das, Subash C; Milligan, Gregg N; Barrett, Alan D T; Partidos, Charalambos D; Osorio, Jorge E

    2014-11-12

    Dengue (DEN) is the most important mosquito-borne viral disease, with a major impact on global health and economics, caused by four serologically and distinct viruses termed DENV-1 to DENV-4. Currently, there is no licensed vaccine to prevent DEN. We have developed a live attenuated tetravalent DENV vaccine candidate (TDV) (formally known as DENVax) that has shown promise in preclinical and clinical studies and elicits neutralizing antibody responses to all four DENVs. As these responses are lowest to DENV-4 we have used the AG129 mouse model to investigate the immunogenicity of monovalent TDV-4 or tetravalent TDV vaccines, and their efficacy against lethal DENV-4 challenge. Since the common backbone of TDV is based on an attenuated DENV-2 strain (TDV-2) we also tested the efficacy of TDV-2 against DENV-4 challenge. Single doses of the tetravalent or monovalent vaccines elicited neutralizing antibodies, anti-NS1 antibodies, and cellular responses to both envelope and nonstructural proteins. All vaccinated animals were protected against challenge at 60 days post-immunization, whereas all control animals died. Investigation of DENV-4 viremias post-challenge showed that only the control animals had high viremias on day 3 post-challenge, whereas vaccinated mice had no detectable viremia. Overall, these data highlight the excellent immunogenicity and efficacy profile of our candidate dengue vaccine in AG129 mice.

  10. Establishment of an in vivo potency assay for the recombinant hepatit is B surface antigen in monovalent and combined vaccines

    Directory of Open Access Journals (Sweden)

    Mabel Izquierdo-López

    2014-12-01

    Full Text Available In this paper the development of potency assay in animals (mice was made, with the objective of demonstrating the immunogenic power of the recombinant Hepatitis B surface antigen in monovalent and combined vaccines, produced at the Center of Genetic Engineering and Biotechnology. The potency test is a parameter in quality control and it is also a tool to demonstrate the consistency of the production process. Parameters such as duration of the test, number of animals in the test, as well as different areas for the maintenance of the animals were evaluated. The results on the applicability of the potency test, to two presentations of the vaccines; monovalent Heberbiovac HB and pentavalent liquid in one vial Heberpenta-L are shown, for which specificity studies, evaluating different vaccine lots, the behavior of linearity, and parallelism, as well as establishing quality specification of the test were performed. This assay led to the obtainment of reliable results for the vaccines evaluated, the consistent evaluation of the immunogenic power and the monitoring of different production processes.

  11. Cationic polymers and porous materials

    KAUST Repository

    Han, Yu

    2017-04-27

    According to one or more embodiments, cationic polymers may be produced which include one or more monomers containing cations. Such cationic polymers may be utilized as structure directing agents to form mesoporous zeolites. The mesoporous zeolites may include micropores as well as mesopores, and may have a surface area of greater than 350 m2/g and a pore volume of greater than 0.3 cm3/g. Also described are core/shell zeolites, where at least the shell portion includes a mesoporous zeolite material.

  12. Evaluation System for Pesticides (ESPE). 1. Agricultural pesticides

    NARCIS (Netherlands)

    Emans HJB; Beek MA; Linders JBHJ

    1992-01-01

    In this report a risk assessment or evaluation system for agricultural pesticides is presented, which estimates the hazards for man and environment resulting from the use of these pesticides. The evaluation system has also been placed within the context of the Uniform System for the Evaluation

  13. Evaluation System for Pesticides (ESPE). 1. Agricultural pesticides

    NARCIS (Netherlands)

    Emans HJB; Beek MA; Linders JBHJ

    1992-01-01

    In this report a risk assessment or evaluation system for agricultural pesticides is presented, which estimates the hazards for man and environment resulting from the use of these pesticides. The evaluation system has also been placed within the context of the Uniform System for the Evaluation of

  14. Cationic Nitrogen Doped Helical Nanographenes.

    Science.gov (United States)

    Xu, Kun; Feng, Xinliang; Berger, Reinhard; Popov, Alexey A; Weigand, Jan J; Vincon, Ilka; Machata, Peter; Hennersdorf, Felix; Zhou, Youjia; Fu, Yubin

    2017-09-13

    Herein, we report on the synthesis of a series of novel cationic nitrogen doped nanographenes (CNDN) by rhodium catalyzed annulation reactions. This powerful method allows for the synthesis of cationic nanographenes with non-planar, axial chiral geometries. Single-crystal X-ray analysis reveals helical and cove-edged structures. Compared to their all-carbon analogues, the CNDN exhibit energetically lower lying frontier orbitals with a reduced optical energy gap and an electron accepting behavior. All derivatives show quasi reversible reductions in cyclic voltammetry. Depending on the number of nitrogen dopant, in situ spectroelectrochemistry proves the formation of neutral radicals (one nitrogen dopant) or radical cations (two nitrogen dopants) upon reduction. The developed synthetic protocol paves the way for the design and synthesis of expanded nanographenes or even graphene nanoribbons containing cationic nitrogen doping. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Asymmetric cation-binding catalysis

    DEFF Research Database (Denmark)

    Oliveira, Maria Teresa; Lee, Jiwoong

    2017-01-01

    and KCN, are selectively bound to the catalyst, providing exceptionally high enantioselectivities for kinetic resolutions, elimination reactions (fluoride base), and Strecker synthesis (cyanide nucleophile). Asymmetric cation-binding catalysis was recently expanded to silicon-based reagents, enabling...... solvents, thus increasing their applicability in synthesis. The expansion of this concept to chiral polyethers led to the emergence of asymmetric cation-binding catalysis, where chiral counter anions are generated from metal salts, particularly using BINOL-based polyethers. Alkali metal salts, namely KF...

  16. Training Manual Occupational Pesticide Exposure & Health and Safe & Responsible Handling of Pesticides

    NARCIS (Netherlands)

    Maden, van der E.C.L.J.; Koomen, I.

    2016-01-01

    Pesticides are commonly used in the horticulture sector. While emphasis is often on the correct and efficient application of pesticides, the risk associated with application of pesticides receives less attention. Those working with pesticides need to know about occupational pesticide exposure and

  17. Fact Sheets on Pesticides in Schools.

    Science.gov (United States)

    National Coalition against the Misuse of Pesticides, Washington, DC.

    This document consists of a collection of fact sheets about the use of pesticides in schools and how to reduce it. The sheets are: (1) "Alternatives to Using Pesticides in Schools: What Is Integrated Pest Management?"; (2) "Health Effects of 48 Commonly Used Pesticides in Schools"; (3) "The Schooling of State Pesticide Laws--2002 Update: A Review…

  18. Immunogenicity and safety of monovalent RIVM meningococcal B OMP vesicle F91 vaccine administered to children that received hexavalent meningococcal B vaccine 2.5 years ago

    NARCIS (Netherlands)

    Lafeber AB; Limpt CJP van; Berbers GAM; Labadie J; Kleijn ED de; Groot R de; Rumke HC; Alphen AJW van; Sophia Kinderziekenhuis /; LVO

    2000-01-01

    This report describes the results with respect to immunogenicity as well as reactogenicity of a monovalent P1.7h,4 OMV vaccine (MonoMen) used as booster vaccination in children previously vaccinated with a hexavalent MenB vaccine. The participants in this study were immunised in 1995-1996 with hexav

  19. International collaboration to assess the risk of Guillain Barré Syndrome following Influenza A (H1N1) 2009 monovalent vaccines

    NARCIS (Netherlands)

    C. Dodd (Caitlin); S.A. Romio (Silvana); S. Black (Steve); C. Vellozzi (Claudia); N.J. Andrews (Nick); M.C.J.M. Sturkenboom (Miriam); P. Zuber (Patrick); W. Hua (Wei); J. Bonhoeffer (Jan); J. Buttery (Jim); N. Crawford (Nigel); G. Deceuninck (Genevieve); C.S. de Vries (Corinne); P. de Wals (Philippe); D. Gimeno (David); H. Heijbel (Harald); H. Hughes (Hayley); K. Hur (Kwan); A. Hviid (Anders); J. Kelman (Jeffrey); T. Kilpi (Tehri); S.K. Chuang (S.); T. Macartney (Thomas); M. Rett (Melisa); V.R. Lopez-Callada (Vesta Richardson); D. Salmon (Daniel); F.G. Sanchez (Francisco Gimenez); N. Sanz (Nuria); B. Silverman (Bernard); J. Storsaeter (Jann); U. Thirugnanam (Umapathi); N.A.T. van der Maas (Nicoline); K. Yih (Katherine); T. Zhang (Teng Fei); H.S. Izurieta (Hector); B.J. Addis; A. Akhtar (Aysha); J. Cope (Judith); R.L. Davis (Robert); P. Gargiullo (Paul); X. Kurz (Xavier); B. Law (Barbara); I. Sahinovic (Isabelle); J. Tokars (Jerry); P. Serrano (Pedro); A. Cheng (Aixin); N.J. Andrews (Nick); P. Charles (Pat); H. Clothier (Hazel); B. Day (Bruce); T. Day (Timothy); P. Gates (Peter); R. MacDonnell (Richard); L. Roberts (Les); V. Rodriguez-Casero (Vic-toria); T. Wijeratne (Tissa); H.A.L. Kiers (Henk); C. Blyth (Christopher); R. Booy (Robert); E. Elliott (Elizabeth); M.R. Gold (Michael); H. Marshall; P. McIntyre (Peter); P. Richmond (Peter); J. Royle (Jenny); N.W. Wood (Nicholas); Y. Zurynski (Yvonne); G. Calvo (Gonzalo); M. Campins (Magda); N. Corominas (Nuria); F. Torres (Ferran); V. Valls; A. Vilella (Ángels); A. Dutra (Amalia); A. Eick-Cost (Angelia); H.M. Jackson (Henry); K. Garman (Katherine); Z. Hu (Zheng); J. Rigo; J. Badoo (Judith); D Cho (David); L.L. Polakowski (Laura); S.K. Sandhu (Sukhminder); G. Sun (Guoying); H.-S.S. Chan (Hoi-Shan Sophelia); K.-Y. Chan (Kwok-Yin); R. Cheung (Raymond); Y-F. Cheung (Yuk-Fai); S. Cherk (Sharon); S.K Chuang (S.); D. Fok (Dennis); B.-H. Fung (Bun-Hey); K.-F. Ko (Kwai-Fu); K.W. Lau (Ka Wing); K.-K. Lau (Kwok-Kwong); P. Li (Pulin); H.-T. Liu (Hui-Tung); S.-H. Liu (Shao-Haei); K. Mok (Kin); J. So (Joanna); W. Wong (Winnie); S.-P. Wu (Shun-Ping); V. Avagyan (Vardan); R. Ball (Robert); D. Burwen (Dale); R.L. Franks (Riley); J.M. Gibbs (Jonathan); R.E. Kliman (Rebecca); S. Kropp (Silke); T.E. MaCurdy (Thomas); D.B. Martin (David); S.-D.K. Sandhu (Sukhmin-Der); B.B. Worrall (Bradford B.); D.E.F. Fuentes (Dra. Elvira Fuentes); P.C.O. González (Paola Carolina Ojeda); V.F. Reyna (Valerie ); M. Kulldorff (Martin); G. Lee (Grace); T.A. Lieu (Tracy); S. Platt; G.D. Serres (Gaston De); K. Jabin (Kamilah); B.L.S. Soh (Bee Leng Sally); L. Arnheim-Dahlström (Lisen); A. Castot (Anne); H.E. de Melker (Hester); J.P. Dieleman (Jeanne); J. Hallgren (Jonal); B.C. Jacobs (Bart); K. Johansen (Kari); P Kramarz (Piotr); M. Lapeyre (Maryse); T. Leino (Tuija); D. Mølgaard-Nielsen (Ditte); M. Mosseveld (Mees); H.K. Olberg (Henning K); C.-M. Sammon (Cor-Mac); C. Saussier (Christel); M.J. Schuemie (Martijn); A. Sommet (Agnès); P. Sparen (Pär); H. Svanström (Henrik); A.M. Vanrolleghem (Ann M.); D.M. Weibel (Daniel); J.D. Domingo (Javier Diez); J.L. Esparza (José LuísMicó); R.M.O. Lucas (Rafael M. Ortí); J.B.M. Maseres (Juan B. Mollar); J.L.A. Sánchez (José Luís Alfonso); M.G. Sánchez (Mercedes Garcés); V.Z. Viguer (Vicente Zanón); F. Cunningham (Francesca); B. Thakkar (Bharat); R. Zhang (Rongping)

    2013-01-01

    textabstractBackground: The global spread of the 2009 novel pandemic influenza A (H1N1) virus led to the accelerated production and distribution of monovalent 2009 Influenza A (H1N1) vaccines (pH1N1). This pandemic provided the opportunity to evaluate the risk of Guillain-Barré syndrome (GBS), which

  20. Immunogenicity and safety of monovalent RIVM meningococcal B OMP vesicle F91 vaccine administered to children that received hexavalent meningococcal B vaccine 2.5 years ago

    NARCIS (Netherlands)

    Lafeber AB; van Limpt CJP; Berbers GAM; Labadie J; de Kleijn ED; de Groot R; Rumke HC; van Alphen AJW; LVO

    2000-01-01

    Dit rapport beschrijft een follow-up studie naar veiligheid en immunogeniciteit van monovalent P1.7h,4 OMV vaccin (MonoMen) gebruikt als boostervaccinatie in kinderen eerder gevaccineerd met hexavalent MenB vaccin. De deelnemers aan deze studie zijn in het kader van een eerdere studie gevaccineerd

  1. International collaboration to assess the risk of Guillain Barré Syndrome following Influenza A (H1N1) 2009 monovalent vaccines

    NARCIS (Netherlands)

    C. Dodd (Caitlin); S.A. Romio (Silvana); S. Black (Steve); C. Vellozzi (Claudia); N.J. Andrews (Nick); M.C.J.M. Sturkenboom (Miriam); P. Zuber (Patrick); W. Hua (Wei); J. Bonhoeffer (Jan); J. Buttery (Jim); N. Crawford (Nigel); G. Deceuninck (Genevieve); C.S. de Vries (Corinne); P. de Wals (Philippe); D. Gimeno (David); H. Heijbel (Harald); H. Hughes (Hayley); K. Hur (Kwan); A. Hviid (Anders); J. Kelman (Jeffrey); T. Kilpi (Tehri); S.K. Chuang (S.); T. Macartney (Thomas); M. Rett (Melisa); V.R. Lopez-Callada (Vesta Richardson); D. Salmon (Daniel); F.G. Sanchez (Francisco Gimenez); N. Sanz (Nuria); B. Silverman (Bernard); J. Storsaeter (Jann); U. Thirugnanam (Umapathi); N.A.T. van der Maas (Nicoline); K. Yih (Katherine); T. Zhang (Teng Fei); H.S. Izurieta (Hector); B.J. Addis; A. Akhtar (Aysha); J. Cope (Judith); R.L. Davis (Robert); P. Gargiullo (Paul); X. Kurz (Xavier); B. Law (Barbara); I. Sahinovic (Isabelle); J. Tokars (Jerry); P. Serrano (Pedro); A. Cheng (Aixin); N.J. Andrews (Nick); P. Charles (Pat); H. Clothier (Hazel); B. Day (Bruce); T. Day (Timothy); P. Gates (Peter); R. MacDonnell (Richard); L. Roberts (Les); V. Rodriguez-Casero (Vic-toria); T. Wijeratne (Tissa); H.A.L. Kiers (Henk); C. Blyth (Christopher); R. Booy (Robert); E. Elliott (Elizabeth); M.R. Gold (Michael); H. Marshall; P. McIntyre (Peter); P. Richmond (Peter); J. Royle (Jenny); N.W. Wood (Nicholas); Y. Zurynski (Yvonne); G. Calvo (Gonzalo); M. Campins (Magda); N. Corominas (Nuria); F. Torres (Ferran); V. Valls; A. Vilella (Ángels); A. Dutra (Amalia); A. Eick-Cost (Angelia); H.M. Jackson (Henry); K. Garman (Katherine); Z. Hu (Zheng); J. Rigo; J. Badoo (Judith); D Cho (David); L.L. Polakowski (Laura); S.K. Sandhu (Sukhminder); G. Sun (Guoying); H.-S.S. Chan (Hoi-Shan Sophelia); K.-Y. Chan (Kwok-Yin); R. Cheung (Raymond); Y-F. Cheung (Yuk-Fai); S. Cherk (Sharon); S.K Chuang (S.); D. Fok (Dennis); B.-H. Fung (Bun-Hey); K.-F. Ko (Kwai-Fu); K.W. Lau (Ka Wing); K.-K. Lau (Kwok-Kwong); P. Li (Pulin); H.-T. Liu (Hui-Tung); S.-H. Liu (Shao-Haei); K. Mok (Kin); J. So (Joanna); W. Wong (Winnie); S.-P. Wu (Shun-Ping); V. Avagyan (Vardan); R. Ball (Robert); D. Burwen (Dale); R.L. Franks (Riley); J.M. Gibbs (Jonathan); R.E. Kliman (Rebecca); S. Kropp (Silke); T.E. MaCurdy (Thomas); D.B. Martin (David); S.-D.K. Sandhu (Sukhmin-Der); B.B. Worrall (Bradford B.); D.E.F. Fuentes (Dra. Elvira Fuentes); P.C.O. González (Paola Carolina Ojeda); V.F. Reyna (Valerie ); M. Kulldorff (Martin); G. Lee (Grace); T.A. Lieu (Tracy); S. Platt; G.D. Serres (Gaston De); K. Jabin (Kamilah); B.L.S. Soh (Bee Leng Sally); L. Arnheim-Dahlström (Lisen); A. Castot (Anne); H.E. de Melker (Hester); J.P. Dieleman (Jeanne); J. Hallgren (Jonal); B.C. Jacobs (Bart); K. Johansen (Kari); P Kramarz (Piotr); M. Lapeyre (Maryse); T. Leino (Tuija); D. Mølgaard-Nielsen (Ditte); M. Mosseveld (Mees); H.K. Olberg (Henning K); C.-M. Sammon (Cor-Mac); C. Saussier (Christel); M.J. Schuemie (Martijn); A. Sommet (Agnès); P. Sparen (Pär); H. Svanström (Henrik); A.M. Vanrolleghem (Ann M.); D.M. Weibel (Daniel); J.D. Domingo (Javier Diez); J.L. Esparza (José LuísMicó); R.M.O. Lucas (Rafael M. Ortí); J.B.M. Maseres (Juan B. Mollar); J.L.A. Sánchez (José Luís Alfonso); M.G. Sánchez (Mercedes Garcés); V.Z. Viguer (Vicente Zanón); F. Cunningham (Francesca); B. Thakkar (Bharat); R. Zhang (Rongping)

    2013-01-01

    textabstractBackground: The global spread of the 2009 novel pandemic influenza A (H1N1) virus led to the accelerated production and distribution of monovalent 2009 Influenza A (H1N1) vaccines (pH1N1). This pandemic provided the opportunity to evaluate the risk of Guillain-Barré syndrome (GBS), which

  2. Monovalent rotavirus vaccine provides protection against an emerging fully heterotypic G9P[4] rotavirus strain in Mexico.

    Science.gov (United States)

    Yen, Catherine; Figueroa, Jesùs Reyna; Uribe, Edgar Sánchez; Carmen-Hernández, Luz Del; Tate, Jacqueline E; Parashar, Umesh D; Patel, Manish M; Richardson López-Collado, Vesta

    2011-09-01

    After the introduction of monovalent rotavirus vaccine (RV1) in Mexico in 2006-2007, diarrhea mortality and morbidity declined substantially among Mexican children under 5 years of age. In January 2010, surveillance identified the emergence of a novel G9P[4] rotavirus strain nationwide. We conducted a case-control study to assess the field effectiveness of RV1 against severe rotavirus gastroenteritis caused by this unusual strain and to determine whether the G9P[4] emergence was related to vaccine failure or failure to vaccinate. RV1 was 94% effective (95% confidence interval, 16%-100%) against G9P[4] rotavirus-related hospitalization, indicating that its emergence was likely unrelated to vaccine pressure.

  3. PESTICIDE APPLICATION TECHNICS IMPROVEMENT

    Directory of Open Access Journals (Sweden)

    Đuro Banaj

    2011-06-01

    Full Text Available The academic textbook Pesticide application tehnics improvement is the result of several-year recording theoretical models, numerous practical tests, and data collection relating to technical systems in plant protection and its environment in the narrowest sense. In this first edition, the authors cover the area they have dealt with for many years. The authors aimed to present complete and clear methods how to solve specific problems in the agricultural practice management, plant protection, and direct practice application – ‘‘Know- How'', with as many as possible useful data. References used, along with local ones, are mostly American and from Western Europe. This textbook is intended for those who already use the agricultural technique in plant protection and those who are just acquiring the basics of technical systems proper application in daily practice, regardless the size of the agricultural farm. The authors covered in details and explained some bases of physics logic, analysis, and synthesis of specific laws while using pesticides due to extremely importance in understanding the problem area.

  4. Highly Tunable Colloidal Perovskite Nanoplatelets through Variable Cation, Metal, and Halide Composition.

    Science.gov (United States)

    Weidman, Mark C; Seitz, Michael; Stranks, Samuel D; Tisdale, William A

    2016-08-23

    Colloidal perovskite nanoplatelets are a promising class of semiconductor nanomaterials-exhibiting bright luminescence, tunable and spectrally narrow absorption and emission features, strongly confined excitonic states, and facile colloidal synthesis. Here, we demonstrate the high degree of spectral tunability achievable through variation of the cation, metal, and halide composition as well as nanoplatelet thickness. We synthesize nanoplatelets of the form L2[ABX3]n-1BX4, where L is an organic ligand (octylammonium, butylammonium), A is a monovalent metal or organic molecular cation (cesium, methylammonium, formamidinium), B is a divalent metal cation (lead, tin), X is a halide anion (chloride, bromide, iodide), and n-1 is the number of unit cells in thickness. We show that variation of n, B, and X leads to large changes in the absorption and emission energy, while variation of the A cation leads to only subtle changes but can significantly impact the nanoplatelet stability and photoluminescence quantum yield (with values over 20%). Furthermore, mixed halide nanoplatelets exhibit continuous spectral tunability over a 1.5 eV spectral range, from 2.2 to 3.7 eV. The nanoplatelets have relatively large lateral dimensions (100 nm to 1 μm), which promote self-assembly into stacked superlattice structures-the periodicity of which can be adjusted based on the nanoplatelet surface ligand length. These results demonstrate the versatility of colloidal perovskite nanoplatelets as a material platform, with tunability extending from the deep-UV, across the visible, into the near-IR. In particular, the tin-containing nanoplatelets represent a significant addition to the small but increasingly important family of lead- and cadmium-free colloidal semiconductors.

  5. Health and environmental hazards of pesticides.

    Science.gov (United States)

    Iyaniwura, T T

    1991-01-01

    The increase in world population and in demand for food and economic crops has put a pesticide burden on man and the environment. Pesticide residues from vector control and agricultural uses contaminate the terrestrial and aquatic surroundings and contribute to the pollution problem of the environment. Various human toxicoses have resulted from pesticide use. The major pathogenic pesticides are chlorinated hydrocarbons and organophosphates. With careful and enlightened use, pesticide toxicity, to both man and the environment, could be significantly reduced.

  6. Structure of a cation-bound multidrug and toxic compound extrusion transporter

    Energy Technology Data Exchange (ETDEWEB)

    He, Xiao; Szewczyk, Paul; Karyakin, Andrey; Evin, Mariah; Hong, Wen-Xu; Zhang, Qinghai; Chang, Geoffrey (Scripps)

    2010-10-26

    Transporter proteins from the MATE (multidrug and toxic compound extrusion) family are vital in metabolite transport in plants, directly affecting crop yields worldwide. MATE transporters also mediate multiple-drug resistance (MDR) in bacteria and mammals, modulating the efficacy of many pharmaceutical drugs used in the treatment of a variety of diseases. MATE transporters couple substrate transport to electrochemical gradients and are the only remaining class of MDR transporters whose structure has not been determined. Here we report the X-ray structure of the MATE transporter NorM from Vibrio cholerae determined to 3.65 {angstrom}, revealing an outward-facing conformation with two portals open to the outer leaflet of the membrane and a unique topology of the predicted 12 transmembrane helices distinct from any other known MDR transporter. We also report a cation-binding site in close proximity to residues previously deemed critical for transport. This conformation probably represents a stage of the transport cycle with high affinity for monovalent cations and low affinity for substrates.

  7. Sorption characteristics of pesticides on matrix substrates used in biopurification systems.

    Science.gov (United States)

    De Wilde, Tineke; Spanoghe, Pieter; Ryckeboer, Jaak; Jaeken, Peter; Springael, Dirk

    2009-03-01

    On-farm biopurification systems were developed to remove pesticides from contaminated water generated at the farmyard. An important process in the system's efficiency is the sorption of pesticides to the substrates used in the biopurification systems. The composition and type of material present in the biobed are crucial for retention of chemicals. This study investigated the sorption of linuron, isoproturon, metalaxyl, isoxaben, bentazon and lenacil on substrates commonly used in a biopurification system, i.e. cow manure, straw, willow chopping, soil, coconut chips, garden waste compost, and peat mix. Linear, Freundlich, and Langmuir sorption isotherms were fitted to the obtained data. The best fit was obtained with the Freundlich model. More immobile pesticides (i.e. linuron and isoxaben) tended to associate with the organic substrate, while more mobile pesticides partition in the water (i.e. bentazon). According to sorption capacity, the substrates could be classified as peat mix > compost, coco chips, straw > cow manure, willow chopping > sandy loam soil. Sorption capacity was positively correlated with the organic carbon content, CaO and the cation exchange capacity. Furthermore, no significant differences in sorption could be found between technical and formulated isoproturon and bentazon. Moreover, the individual sorption coefficient K(d) was additive, which means that individual sorption coefficients can be used to calculate the sorption coefficients of a mixture of substrates. What concerns the mutual interaction of pesticides it could be observed that the sorption of linuron and metalaxyl was significantly lower in combination with isoproturon and bentazon, while the latter pesticides were not influenced by the presence of linuron and metalaxyl. As guidelines, firstly, it could be stated that using the most sorbing materials such as peat mix, might significantly increase the biopurification systems efficiency. Secondly, the treatment of very mobile

  8. Analytical methods for detecting pesticide switches with evolution of pesticide resistance

    OpenAIRE

    Liang, Juhua; Tang, Sanyi; Juan J. Nieto; Cheke, Robert A.

    2013-01-01

    After a pest develops resistance to a pesticide, switching between different unrelated pesticides is a common management option, but this raises the following questions: (1) What is the optimal frequency of pesticide use? (2) How do the frequencies of pesticide applications affect the evolution of pesticide resistance? (3) How can the time when the pest population reaches the economic injury level (EIL) be estimated and (4) how can the most efficient frequency of pesticide applications be dete...

  9. Cation Dependence, pH Tolerance, and Dosage Requirement of a Bioflocculant Produced by Bacillus spp. UPMB13: Flocculation Performance Optimization through Kaolin Assays

    Science.gov (United States)

    Zulkeflee, Zufarzaana; Aris, Ahmad Zaharin; Shamsuddin, Zulkifli H.; Yusoff, Mohd Kamil

    2012-01-01

    A bioflocculant-producing bacterial strain with highly mucoid and ropy colony morphological characteristics identified as Bacillus spp. UPMB13 was found to be a potential bioflocculant-producing bacterium. The effect of cation dependency, pH tolerance and dosage requirement on flocculating ability of the strain was determined by flocculation assay with kaolin as the suspended particle. The flocculating activity was measured as optical density and by flocs formation. A synergistic effect was observed with the addition of monovalent and divalent cations, namely, Na+, Ca2+, and Mg2+, while Fe2+ and Al3+ produced inhibiting effects on flocculating activity. Divalent cations were conclusively demonstrated as the best cation source to enhance flocculation. The bioflocculant works in a wide pH range, from 4.0 to 8.0 with significantly different performances (P < 0.05), respectively. It best performs at pH 5.0 and pH 6.0 with flocculating performance of above 90%. A much lower or higher pH would inhibit flocculation. Low dosage requirements were needed for both the cation and bioflocculant, with only an input of 50 mL/L for 0.1% (w/v) CaCl2 and 5 mL/L for culture broth, respectively. These results are comparable to other bioflocculants produced by various microorganisms with higher dosage requirements. PMID:22997497

  10. Cation Dependence, pH Tolerance, and Dosage Requirement of a Bioflocculant Produced by Bacillus spp. UPMB13: Flocculation Performance Optimization through Kaolin Assays

    Directory of Open Access Journals (Sweden)

    Zufarzaana Zulkeflee

    2012-01-01

    Full Text Available A bioflocculant-producing bacterial strain with highly mucoid and ropy colony morphological characteristics identified as Bacillus spp. UPMB13 was found to be a potential bioflocculant-producing bacterium. The effect of cation dependency, pH tolerance and dosage requirement on flocculating ability of the strain was determined by flocculation assay with kaolin as the suspended particle. The flocculating activity was measured as optical density and by flocs formation. A synergistic effect was observed with the addition of monovalent and divalent cations, namely, Na+, Ca2+, and Mg2+, while Fe2+ and Al3+ produced inhibiting effects on flocculating activity. Divalent cations were conclusively demonstrated as the best cation source to enhance flocculation. The bioflocculant works in a wide pH range, from 4.0 to 8.0 with significantly different performances (P<0.05, respectively. It best performs at pH 5.0 and pH 6.0 with flocculating performance of above 90%. A much lower or higher pH would inhibit flocculation. Low dosage requirements were needed for both the cation and bioflocculant, with only an input of 50 mL/L for 0.1% (w/v CaCl2 and 5 mL/L for culture broth, respectively. These results are comparable to other bioflocculants produced by various microorganisms with higher dosage requirements.

  11. Radiation induced pesticidal microbes

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ki Yup; Lee, Y. K.; Kim, J. S.; Kim, J. K.; Lee, S. J.; Lim, D. S

    2001-01-01

    To isolate pesticidal microbes against plant pathogenic fungi, 4 strains of bacteria(K1. K3, K4, YS1) were isolated from mushroom compost and hot spring. K4, K1, K3, YS1 strain showed wide antifungal spectrum and high antifungal activities against 12 kinds of fungi. Specific proteins and the specific transcribed genes were found from the YS1 and its radiation-induced mutants. And knock-out mutants of antifungal activity were derived by transposon mutagenesis. From these knock-out mutants, the antifungal activity related genes and its modification by gamma-ray radiation are going to be studied. These results suggested that radiation could be an useful tool for the induction of functional mutants.

  12. Pesticide Product Information System (PPIS)

    Science.gov (United States)

    PPIS includes registrant name and address, chemical ingredients, toxicity category, product names, distributor brand names, site/pest uses, pesticidal type, formulation code, and registration status for all products registered in the U.S.

  13. Pesticides (Environmental Health Student Portal)

    Science.gov (United States)

    ... Pollution Air Pollution Home Indoor Air Pollution Outdoor Air Pollution Particulate Matter Ozone Chemicals Chemicals Home Mercury Lead Arsenic Volatile Organic Compounds Plastics Pesticides Climate Change Climate Change Home What is Climate Change Greenhouse ...

  14. Consumer Products Treated with Pesticides

    Science.gov (United States)

    Many products (e.g., cutting boards, kitchen sponges, cat litter, toothbrushes and juvenile toys) are being treated with antimicrobial pesticides. Learn about requirements that apply to such products.

  15. Pesticides to Control Bed Bugs

    Science.gov (United States)

    More than 300 pesticide products in seven chemical classes are registered with EPA, meaning EPA has evaluated their safety and effectiveness: pyrethins, pyrethroids, desiccants, biochemicals, pyrroles, neonicotinoids, and insect growth regulators.

  16. In Case of Pesticide Emergency

    Science.gov (United States)

    ... Call the Poison Control Center at 1-800-222-1222 for help with first aid information. The ... Health Land, Waste, and Cleanup Lead Mold Pesticides Radon Science Water A-Z Index Laws & Regulations By ...

  17. Research progress in cation-π interactions

    Institute of Scientific and Technical Information of China (English)

    CHENG JiaGao; LUO XiaoMin; YAN XiuHua; LI Zhong; TANG Yun; JIANG HuaLiang; ZHU WeiLiang

    2008-01-01

    Cation-π interaction is a potent intermolecular interaction between a cation and an aromatic system, which has been viewed as a new kind of binding force, as being compared with the classical interac-tions (e.g. hydrogen bonding, electrostatic and hydrophobic interactions). Cation-π interactions have been observed in a wide range of biological contexts. In this paper, we present an overview of the typi-cal cation-π interactions in biological systems, the experimental and theoretical investigations on cation-π interactions, as well as the research results on cation-π interactions in our group.

  18. Research progress in cation-π interactions

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Cation-π interaction is a potent intermolecular interaction between a cation and an aromatic system,which has been viewed as a new kind of binding force,as being compared with the classical interactions(e.g. hydrogen bonding,electrostatic and hydrophobic interactions). Cation-π interactions have been observed in a wide range of biological contexts. In this paper,we present an overview of the typical cation-π interactions in biological systems,the experimental and theoretical investigations on cation-π interactions,as well as the research results on cation-π interactions in our group.

  19. Pesticides' influence on wine fermentation.

    Science.gov (United States)

    Caboni, Pierluigi; Cabras, Paolo

    2010-01-01

    Wine quality strongly depends on the grape quality. To obtain high-quality wines, it is necessary to process healthy grapes at the correct ripeness stage and for this reason the farmer has to be especially careful in the prevention of parasite attacks on the grapevine. The most common fungal diseases affecting grape quality are downy and powdery mildew (Plasmopara viticola and Uncinula necator), and gray mold (Botrytis cinerea). On the other hand, the most dangerous insects are the grape moth (Lobesia botrana), vine mealybug (Planococcus ficus), and the citrus mealybug (Planococcus citri). Farmers fight grape diseases and insects applying pesticides that can be found at harvest time on grapes. The persistence of pesticides depends on the chemical characteristic of the active ingredients as well as on photodegradation, thermodegradation, codistillation, and enzymatic degradation. The pesticide residues on grapes can be transferred to the must and this can influence the selection and development of yeast strains. Moreover, yeasts can also influence the levels of the pesticides in the wine by reducing or adsorbing them on lees. During the fermentative process, yeasts can cause the disappearance of pesticide residues by degradation or absorption at the end of the fermentation when yeasts are deposited as lees. In this chapter, we reviewed the effect of commonly used herbicides, insecticides, and fungicides on yeasts. We also studied the effect of alcoholic and malolactic fermentation on pesticide residues.

  20. Hair as a marker for pesticides exposure.

    Science.gov (United States)

    Smith-Baker, Charlotte; Saleh, Mahmoud A

    2011-01-01

    Rats were orally treated with mixtures of chlorinated pesticides. Hair was collected and analyzed for pesticide residues over a period of up to four weeks. Quantitative and qualitative analysis of the recovered pesticides in hair were determined using gas chromatography with electron capture detector. Results suggest that hair can be used as a biomarker for the monitoring of organochlorinated pesticide residues at low parts per billion levels. Chlorinated pesticides were also detected in human hair of environmentally exposed and occupationally exposed individuals, which indicates that hair can be used for monitoring pesticides exposure.

  1. Impact of sediment-seawater cation exchange on Himalayan chemical weathering fluxes

    Science.gov (United States)

    Lupker, Maarten; France-Lanord, Christian; Lartiges, Bruno

    2016-08-01

    Continental-scale chemical weathering budgets are commonly assessed based on the flux of dissolved elements carried by large rivers to the oceans. However, the interaction between sediments and seawater in estuaries can lead to additional cation exchange fluxes that have been very poorly constrained so far. We constrained the magnitude of cation exchange fluxes from the Ganga-Brahmaputra river system based on cation exchange capacity (CEC) measurements of riverine sediments. CEC values of sediments are variable throughout the river water column as a result of hydrological sorting of minerals with depth that control grain sizes and surface area. The average CEC of the integrated sediment load of the Ganga-Brahmaputra is estimated ca. 6.5 meq 100 g-1. The cationic charge of sediments in the river is dominated by bivalent ions Ca2+ (76 %) and Mg2+ (16 %) followed by monovalent K+ (6 %) and Na+ (2 %), and the relative proportion of these ions is constant among all samples and both rivers. Assuming a total exchange of exchangeable Ca2+ for marine Na+ yields a maximal additional Ca2+ flux of 28 × 109 mol yr-1 of calcium to the ocean, which represents an increase of ca. 6 % of the actual river dissolved Ca2+ flux. In the more likely event that only a fraction of the adsorbed riverine Ca2+ is exchanged, not only for marine Na+ but also Mg2+ and K+, estuarine cation exchange for the Ganga-Brahmaputra is responsible for an additional Ca2+ flux of 23 × 109 mol yr-1, while ca. 27 × 109 mol yr-1 of Na+, 8 × 109 mol yr-1 of Mg2+ and 4 × 109 mol yr-1 of K+ are re-absorbed in the estuaries. This represents an additional riverine Ca2+ flux to the ocean of 5 % compared to the measured dissolved flux. About 15 % of the dissolved Na+ flux, 8 % of the dissolved K+ flux and 4 % of the Mg2+ are reabsorbed by the sediments in the estuaries. The impact of estuarine sediment-seawater cation exchange appears to be limited when evaluated in the context of the long-term carbon cycle and

  2. Cation size effects in mixed-ion metaphosphate glasses: structural characterization by multinuclear solid state NMR spectroscopy.

    Science.gov (United States)

    Schneider, J; Tsuchida, J; Eckert, H

    2013-09-14

    Metaphosphate glasses with two monovalent species A(1-x)B(x)PO3 (0 ≤x≤ 1) show mixed-ion effects (MIE) in the dc conductivities and glass transition temperatures, which are strongly dependent on the cation size mismatch between the two mobile species. In the present contribution, mixed-ion metaphosphate glasses based on the cation combinations Cs-Li, Rb-Li, and Cs-Ag, exhibiting particularly large size mismatches, are analyzed by (31)P, (87)Rb, (109)Ag and (133)Cs NMR to determine possible correlations between this mismatch and some of the structural properties critical to the development of the MIE: the local environments around the mobile species and their spatial distribution relative to each other. The results are compared with those obtained in the Na-Ag metaphosphate series, which serves as a reference system, with minimized cation mismatch MIE. The local coordination environments of the Ag(+), Rb(+) and Cs(+) ions follow analogous compositional trends as previously observed in Na-based mixed-ion metaphosphate glasses: for a given cation species A, the average A-O distance shows an expansion/compression when this cation is replaced by a second species B with smaller/bigger ionic radius, respectively. This compositional differentiation of the structural sites for the mobile species may contribute to the MIE. Concerning the relative spatial distribution of the mobile ions, results from (7)Li-(133)Cs (SEDOR) experiments indicate a random mixture of Cs and Li in Cs-Li metaphosphate glasses. While this result is in agreement with one of the fundamental hypotheses of the models proposed to describe the MIE, it is at variance with the observation of various partial cation segregation phenomena observed in Na-based mixed alkali glasses. This result suggests that cation size mismatch is not the decisive parameter in determining segregation or non-statistical mixing of cations in the glass. In the Cs-Ag and Na-Ag glasses, (109)Ag spin-echo NMR reveals a progressive

  3. 40 CFR 158.2010 - Biochemical pesticides data requirements.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Biochemical pesticides data...) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Biochemical Pesticides § 158.2010 Biochemical pesticides... required to support registration of biochemical pesticides. Sections 158.2080 through 158.2084 identify...

  4. 40 CFR 158.2110 - Microbial pesticides data requirements.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Microbial pesticides data requirements...) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Microbial Pesticides § 158.2110 Microbial pesticides data requirements. (a) For all microbial pesticides. (1) The following § 158.2120 through §...

  5. 40 CFR 152.175 - Pesticides classified for restricted use.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Pesticides classified for restricted...) PESTICIDE PROGRAMS PESTICIDE REGISTRATION AND CLASSIFICATION PROCEDURES Classification of Pesticides § 152.175 Pesticides classified for restricted use. The following uses of pesticide products containing the...

  6. 40 CFR 158.2100 - Microbial pesticides definition and applicability.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Microbial pesticides definition and...) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Microbial Pesticides § 158.2100 Microbial pesticides definition and applicability. (a) This subpart applies to all living or dead microbial pesticides as...

  7. Tripodal Receptors for Cation and Anion Sensors

    NARCIS (Netherlands)

    Kuswandi, Bambang; Nuriman,; Verboom, Willem; Reinhoudt, David N.

    2006-01-01

    This review discusses different types of artificial tripodal receptors for the selectiverecognition and sensing of cations and anions. Examples on the relationship between structure andselectivity towards cations and anions are described. Furthermore, their applications as potentiometricion sensing

  8. Heavy metal cations permeate the TRPV6 epithelial cation channel.

    Science.gov (United States)

    Kovacs, Gergely; Danko, Tamas; Bergeron, Marc J; Balazs, Bernadett; Suzuki, Yoshiro; Zsembery, Akos; Hediger, Matthias A

    2011-01-01

    TRPV6 belongs to the vanilloid family of the transient receptor potential channel (TRP) superfamily. This calcium-selective channel is highly expressed in the duodenum and the placenta, being responsible for calcium absorption in the body and fetus. Previous observations have suggested that TRPV6 is not only permeable to calcium but also to other divalent cations in epithelial tissues. In this study, we tested whether TRPV6 is indeed also permeable to cations such as zinc and cadmium. We found that the basal intracellular calcium concentration was higher in HEK293 cells transfected with hTRPV6 than in non-transfected cells, and that this difference almost disappeared in nominally calcium-free solution. Live cell imaging experiments with Fura-2 and NewPort Green DCF showed that overexpression of human TRPV6 increased the permeability for Ca(2+), Ba(2+), Sr(2+), Mn(2+), Zn(2+), Cd(2+), and interestingly also for La(3+) and Gd(3+). These results were confirmed using the patch clamp technique. (45)Ca uptake experiments showed that cadmium, lanthanum and gadolinium were also highly efficient inhibitors of TRPV6-mediated calcium influx at higher micromolar concentrations. Our results suggest that TRPV6 is not only involved in calcium transport but also in the transport of other divalent cations, including heavy metal ions, which may have toxicological implications.

  9. 77 FR 23713 - Pesticides; Final Guidance on Material Safety Data Sheets as Pesticide Labeling; Request for...

    Science.gov (United States)

    2012-04-20

    ... relationship between EPA-approved labels for pesticides registered under the Federal Insecticide, Fungicide... AGENCY Pesticides; Final Guidance on Material Safety Data Sheets as Pesticide Labeling; Request for.... SUMMARY: The Agency is announcing the availability of a Pesticide Registration Notice (PR Notice)...

  10. Immunotoxicity of organophosphorous pesticides.

    Science.gov (United States)

    Galloway, Tamara; Handy, Richard

    2003-01-01

    This study reviews the toxic effects of organophosphate (OP) pesticides on the immune systems and immune functions of invertebrates, fish, and higher vertebrate wildlife. The fundamental features and mechanisms of OP-induced immunotoxicity are illustrated with reference to parathion, chlorpyrifos, malathion, and diazinon. Immunotoxicity may be direct via inhibition of serine hydrolases or esterases in components of the immune system, through oxidative damage to immune organs, or by modulation of signal transduction pathways controlling immune functions. Indirect effects include modulation by the nervous system, or chronic effects of altered metabolism/nutrition on immune organs. Immunotoxicities are varied and include pathology of immune organs, and decreased humoral and/or cell mediated immunity. Altered non-specific immunity, decreased host resistance, hypersensitivity and autoimmunity are also features of immunotoxicity; although not all of these have been conclusively demonstrated in terms of pollutant exposure and immunotoxic effects in wildlife within individual experiments. Immunotoxicological biomarkers and biological monitoring tools are urgently needed to assess the extent of immunotoxicity in wildlife. Selection of universal biomarkers is hampered by the physiological diversity of immune systems in animals. However, by drawing on evidence from human epidemiology and tiered approaches in mammalian immunotoxicity evaluation, a selection of generic biomarkers of immunotoxicity in animals is suggested. Priorities for future research are also identified.

  11. The protective efficacy of cloned Moraxella bovis pili in monovalent and multivalent vaccine formulations against experimentally induced infectious bovine keratoconjunctivitis (IBK).

    Science.gov (United States)

    Lepper, A W; Atwell, J L; Lehrbach, P R; Schwartzkoff, C L; Egerton, J R; Tennent, J M

    1995-07-01

    Calves were vaccinated with cloned Moraxella bovis pili of serogroup C (experiment 1) or B (experiment 2) either as a monovalent formulation or as part of a multivalent preparation with pili of six other serogroups. Within 4 weeks of the second vaccine dose vaccinated calves and non-vaccinated controls were challenged via the ocular route with either virulent M. bovis strain Dal2d (serogroup C) or M. bovis strain 3WO7 (serogroup B) in experiments 1 and 2, respectively. Calves vaccinated with multivalent vaccines had significantly lower antibody titres than those vaccinated with monovalent preparations. Nevertheless, the levels of protection against infectious bovine keratoconjunctivitis (IBK) achieved with multivalent vaccines were 72% and 83% for the groups challenged with M. bovis strains of serogroups B and C, respectively. The serogroup C monovalent vaccine gave 100% protection against experimentally induced IBK and M. bovis isolates cultured from the eyes 6 days post-challenge were identified as belonging solely to serogroup C. Unexpectedly, only 25% protection was achieved against homologous strain challenge of calves that received the monovalent serogroup B vaccine. Furthermore, the majority of M. bovis isolates recovered from calves in this group belonged to serogroup C, as did half of those isolates cultured from the multivalent vaccinates. The remaining bacterial isolates from the latter group, together with all isolates from the non-vaccinated controls, belonged to serogroup B. Results are consistent with the hypothesis that derivatives of the serogroup B challenge inoculum had expressed serogroup C pilus antigen within 6 days of the challenge, possibly as a result of pilus gene inversion occurring in response to the presence of specific antibody in eye tissues and tears.

  12. Pesticide Exposures May Alter Mouth Bacteria

    Science.gov (United States)

    ... fullstory_162249.html Pesticide Exposures May Alter Mouth Bacteria Study of Washington farm workers finds alterations persist ... News) -- Pesticide exposure may change the makeup of bacteria in the mouths of farm workers, a new ...

  13. Pesticide risks around the home (image)

    Science.gov (United States)

    Pesticides are substances which kill or deter unwanted pests, such as insects or rodents. These substances can ... avoid an accidental ingestion is to keep all pesticides out of the reach of children.

  14. 75 FR 4383 - Pesticide Products: Registration Applications

    Science.gov (United States)

    2010-01-27

    ... AGENCY Pesticide Products: Registration Applications AGENCY: Environmental Protection Agency (EPA). ACTION: Notice. SUMMARY: This notice announces receipt of applications to register pesticide products... comments by the comment period deadline identified. II. Registration Applications EPA received applications...

  15. 76 FR 38160 - Pesticide Products; Registration Applications

    Science.gov (United States)

    2011-06-29

    ... AGENCY Pesticide Products; Registration Applications AGENCY: Environmental Protection Agency (EPA). ACTION: Notice. SUMMARY: EPA has received applications to register pesticide products containing an... hereby providing notice of receipt and opportunity to comment on these applications. DATES: Comments must...

  16. 75 FR 80490 - Pesticide Products; Registration Applications

    Science.gov (United States)

    2010-12-22

    ... AGENCY Pesticide Products; Registration Applications AGENCY: Environmental Protection Agency (EPA). ACTION: Notice. SUMMARY: EPA has received applications to register pesticide products containing active... providing notice of receipt and opportunity to comment on these applications. DATES: Comments must be...

  17. 76 FR 63298 - Pesticide Products; Registration Applications

    Science.gov (United States)

    2011-10-12

    ...] Pesticide Products; Registration Applications AGENCY: Environmental Protection Agency (EPA). ACTION: Notice. SUMMARY: EPA has received applications to register pesticide products containing active ingredients not... receipt and opportunity to comment on these applications. DATES: Comments must be received on or before...

  18. 75 FR 23759 - Pesticide Products; Registration Applications

    Science.gov (United States)

    2010-05-04

    ... AGENCY Pesticide Products; Registration Applications AGENCY: Environmental Protection Agency (EPA). ACTION: Notice. SUMMARY: EPA has received applications to register pesticide products containing an... providing notice of receipt and opportunity to comment on these applications. DATES: Comments must be...

  19. 75 FR 71695 - Pesticide Products; Registration Applications

    Science.gov (United States)

    2010-11-24

    ... AGENCY Pesticide Products; Registration Applications AGENCY: Environmental Protection Agency ACTION: Notice. SUMMARY: EPA has received applications to register new uses for pesticide products containing... to comment on these applications. DATES: Comments must be received on or before December 27, 2010...

  20. 75 FR 24694 - Pesticide Products; Registration Applications

    Science.gov (United States)

    2010-05-05

    ... AGENCY Pesticide Products; Registration Applications AGENCY: Environmental Protection Agency (EPA). ACTION: Notice. SUMMARY: EPA has received applications to register pesticide products containing an... providing notice of receipt and opportunity to comment on these applications. DATES: Comments must be...

  1. 75 FR 8939 - Pesticide Products; Registration Applications

    Science.gov (United States)

    2010-02-26

    ... AGENCY Pesticide Products; Registration Applications AGENCY: Environmental Protection Agency (EPA). ACTION: Notice. SUMMARY: EPA has received applications to register pesticide products containing an... hereby providing notice of receipt and opportunity to comment on these applications. DATES: Comments must...

  2. Chiral Pesticides: Identification, Description and Environmental Implications

    Science.gov (United States)

    Anthropogenic chemicals, including pesticides, are a major source of contamination and pollution in the environment. Pesticides have many positive uses: increased food production, decreased damage to crops and structures, reduced disease vector populations, and more. Nevertheless...

  3. Assessing Human Health Risk from Pesticides

    Science.gov (United States)

    EPA protects human health and the environment by evaluating the risk associated with pesticides before allowing them to be used in the United States. Learn about the tools and processes used in risk assessment for pesticides.

  4. How We Engage Our Pesticide Stakeholders

    Science.gov (United States)

    The success of EPA's pesticide program is directly connected to our efforts to engage all stakeholders. In addition to meetings on pesticide-specific actions, we sponsor advisory committees that include diverse, independent stakeholders.

  5. Neurobehavioral and neurodevelopmental effects of pesticide exposures

    NARCIS (Netherlands)

    London, L.; Beseler, C.; Bouchard, M.F.; Bellinger, D.C.; Colosio, C.; Grandjean, P.; Harari, R.; Kootbodien, T.; Kromhout, H.; Little, F.; Meijster, T.; Moretto, A.; Rohlman, D.S.; Stallones L.

    2012-01-01

    The association between pesticide exposure and neurobehavioral and neurodevelopmental effects is an area of increasing concern. This symposium brought together participants to explore the neurotoxic effects of pesticides across the lifespan. Endpoints examined included neurobehavioral, affective and

  6. Chiral Pesticides: Identification, Description and Environmental Implications

    Science.gov (United States)

    Anthropogenic chemicals, including pesticides, are a major source of contamination and pollution in the environment. Pesticides have many positive uses: increased food production, decreased damage to crops and structures, reduced disease vector populations, and more. Nevertheless...

  7. Neurobehavioral and neurodevelopmental effects of pesticide exposures

    DEFF Research Database (Denmark)

    London, Leslie; Beseler, Cheryl; Bouchard, Maryse F

    2012-01-01

    The association between pesticide exposure and neurobehavioral and neurodevelopmental effects is an area of increasing concern. This symposium brought together participants to explore the neurotoxic effects of pesticides across the lifespan. Endpoints examined included neurobehavioral, affective ...

  8. Hexadimethrine-montmorillonite nanocomposite: Characterization and application as a pesticide adsorbent

    Energy Technology Data Exchange (ETDEWEB)

    Gámiz, B., E-mail: bgamiz@irnase.csic.es; Hermosín, M.C.; Cornejo, J.; Celis, R.

    2015-03-30

    Graphical abstract: - Highlights: • Characterization of hexadimethrine-montmorillonite nanocomposite was appraised. • Comparative studies with traditional HDTMA-montmorillonite were performed. • We investigated the pesticide adsorption mechanisms displayed by the nanocomposites. • Hexadimethrine-nanocomposite showed selective affinity for anionic pesticides. - Abstract: The goal of this work was to prepare and characterize a novel functional material by the modification of SAz-1 montmorillonite with the cationic polymer hexadimethrine (SA-HEXAD), and to explore the potential use of this nanocomposite as a pesticide adsorbent. Comparative preparation and characterization with the well-known hexadecyltrimethylammonium-modified SAz-1 montmorillonite (SA-HDTMA) was also assessed. The characterization was performed by elemental analysis, X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), physisorption of N{sub 2}, scanning electron microscopy (SEM) and Z potential measurements. The characterization and adsorption experiments showed that the extent of pesticide adsorption was markedly subjected to the structure and features of the surface of each organo-clay and also to the nature of the considered pesticide. SA-HEXAD displayed a high affinity for anionic pesticides which, presumably, were adsorbed by electrostatic attraction on positively-charged ammonium groups of the polymer not directly interacting with the clay. In contrast, SA-HDTMA displayed great adsorption of both uncharged and anionic pesticides with predominance of hydrophobic interactions. This work provided information about the surface properties of a new organic–inorganic nanohybrid material, SA-HEXAD, and its potential as an adsorbent for the removal of anionic organic pollutants from aqueous solutions.

  9. Organochlorine Pesticides in the Environment

    Science.gov (United States)

    Stickel, L.F.

    1968-01-01

    Each year for nearly 20 years, thousands of pounds of persistent organochlorine pesticides have been applied to outdoor areas in many countries. These compounds may last for a very long time in the environment, and be carried by wind, water, and animals to places far distant from where they are used. As a result, most living organisms now contain organochlorine residues. This paper constitutes a selective review of the literature concerning the occurrence, distribution, and effects of organochlorines in the environment. Highest concentrations generally occur in carnivorous species. Thus predatory and fish-eating birds ordinarily have higher residues than do herbivores; quantities are similar in birds of similar habits in different countries. Any segment of the ecosystem - marshland, pond, forest, or field - receives various amounts and kinds of pesticides at irregular intervals. The different animals absorb, detoxify, store, and excrete pesticides at different rates. Different degrees of magnification of pesticide residues by living organisms in an environment are the practical result of many interactions that are far more complex than implied by the statement of magnification up the food chain. These magnifications may be millions of times from water to mud or only a few times from food to first consumer. Direct mortality of wild animals as an aftermath of recommended pesticide treatments has been recorded in the literature of numerous countries. However, accidents and carelessness also accompany pesticide use on a percentage basis and are a part of the problem. More subtle effects on the size and species composition of populations are more difficult to perceive in time to effect remedies. The possibility of ecological effects being mediated through changes in physiology and behavior has received some attention and has resulted in some disquieting findings. These include discovery of the activity of organochlorines in stimulating the breakdown of hormones or in

  10. Non-covalent ligand conjugation to biotinylated DNA nanoparticles using TAT peptide genetically fused to monovalent streptavidin.

    Science.gov (United States)

    Sun, Wenchao; Fletcher, David; van Heeckeren, Rolf Christiaan; Davis, Pamela B

    2012-09-01

    DNA nanoparticles (DNA NPs), which self-assemble from DNA plasmids and poly-L-lysine (pLL)-polyethylene glycol (PEG) block copolymers, transfect several cell types in vitro and in vivo with minimal toxicity and immune response. To further enhance the gene transfer efficiency of DNA NP and control its tropism, we established a strategy to efficiently attach peptide ligands to DNA NPs. The non-covalent biotin-streptavidin (SA) interaction was used for ligand conjugation to overcome problems associated with covalent conjugation methods. A fusion protein of SA with the HIV-1 TAT peptide was cloned, expressed, purified and attached to biotinylated DNA NPs. A modified SA system with tetrameric structure but monovalent biotin binding capacity was adopted and shown to reduce the aggregation of biotinylated DNA NPs compared to neutravidin. Compared to unmodified DNA NPs, TAT modified DNA NPs significantly enhanced in vitro gene transfer, particularly at low DNA concentrations. Studies of cellular uptake and cellular distribution of the DNA NPs indicated that attaching TAT enhanced binding of DNA NPs to cell surface but not internalization at high DNA concentrations. In vivo studies showed that TAT modified DNA NPs mediated equal level of gene transfer to the mouse airways via the luminal route compared to unmodified DNA NPs.

  11. Monovalent Ions and Water Dipoles in Contact with Dipolar Zwitterionic Lipid Headgroups-Theory and MD Simulations

    Directory of Open Access Journals (Sweden)

    Aljaž Velikonja

    2013-01-01

    Full Text Available The lipid bilayer is a basic building block of biological membranes and can be pictured as a barrier separating two compartments filled with electrolyte solution. Artificial planar lipid bilayers are therefore commonly used as model systems to study the physical and electrical properties of the cell membranes in contact with electrolyte solution. Among them the glycerol-based polar phospholipids which have dipolar, but electrically neutral head groups, are most frequently used in formation of artificial lipid bilayers. In this work the electrical properties of the lipid layer composed of zwitterionic lipids with non-zero dipole moments are studied theoretically. In the model, the zwitterionic lipid bilayer is assumed to be in contact with aqueous solution of monovalent salt ions. The orientational ordering of water, resulting in spatial variation of permittivity, is explicitly taken into account. It is shown that due to saturation effect in orientational ordering of water dipoles the relative permittivity in the zwitterionic headgroup region is decreased, while the corresponding electric potential becomes strongly negative. Some of the predictions of the presented mean-field theoretical consideration are critically evaluated using the results of molecular dynamics (MD simulation.

  12. The role of aspartate-235 in the binding of cations to an artificial cavity at the radical site of cytochrome c peroxidase.

    Science.gov (United States)

    Fitzgerald, M M; Trester, M L; Jensen, G M; McRee, D E; Goodin, D B

    1995-09-01

    The activated state of cytochrome c peroxidase, compound ES, contains a cation radical on the Trp-191 side chain. We recently reported that replacing this tryptophan with glycine creates a buried cavity at the active site that contains ordered solvent and that will specifically bind substituted imidazoles in their protonated cationic forms (Fitzgerald MM, Churchill MJ, McRee DE, Goodin DB, 1994, Biochemistry 33:3807-3818). Proposals that a nearby carboxylate, Asp-235, and competing monovalent cations should modulate the affinity of the W191G cavity for ligand binding are addressed in this study. Competitive binding titrations of the imidazolium ion to W191G as a function of [K+] show that potassium competes weakly with the binding of imidazoles. The dissociation constant observed for potassium binding (18 mM) is more than 3,000-fold higher than that for 1,2-dimethylimidazole (5.5 microM) in the absence of competing cations. Significantly, the W191G-D235N double mutant shows no evidence for binding imidazoles in their cationic or neutral forms, even though the structure of the cavity remains largely unperturbed by replacement of the carboxylate. Refined crystallographic B-values of solvent positions indicate that the weakly bound potassium in W191G is significantly depopulated in the double mutant. These results demonstrate that the buried negative charge of Asp-235 is an essential feature of the cation binding determinant and indicate that this carboxylate plays a critical role in stabilizing the formation of the Trp-191 radical cation.

  13. In-vitro Neurotoxicity of Two Malaysian Krait Species (Bungarus candidus and Bungarus fasciatus Venoms: Neutralization by Monovalent and Polyvalent Antivenoms from Thailand

    Directory of Open Access Journals (Sweden)

    Muhamad Rusdi Ahmad Rusmili

    2014-03-01

    Full Text Available Bungarus candidus and Bungarus fasciatus are two species of krait found in Southeast Asia. Envenoming by these snakes is often characterized by neurotoxicity and, without treatment, causes considerable morbidity and mortality. In this study, the in vitro neurotoxicity of each species, and the effectiveness of two monovalent antivenoms and a polyvalent antivenom, against the neurotoxic effects of the venoms, were examined in a skeletal muscle preparation. Both venoms caused concentration-dependent inhibition of indirect twitches, and attenuated responses to exogenous nicotinic receptor agonists, in the chick biventer preparation, with B. candidus venom being more potent than B. fasciatus venom. SDS-PAGE and western blot analysis indicated different profiles between the venoms. Despite these differences, most proteins bands were recognized by all three antivenoms. Antivenom, added prior to the venoms, attenuated the neurotoxic effect of the venoms. Interestingly, the respective monovalent antivenoms did not neutralize the effects of the venom from the other Bungarus species indicating a relative absence of cross-neutralization. Addition of a high concentration of polyvalent antivenom, at the t90 time point after addition of venom, partially reversed the neurotoxicity of B. fasciatus venom but not B. candidus venom. The monovalent antivenoms had no significant effect when added at the t90 time point. This study showed that B. candidus and B. fasciatus venoms display marked in vitro neurotoxicity in the chick biventer preparation and administration of antivenoms at high dose is necessary to prevent or reverse neurotoxicity.

  14. In-vitro neurotoxicity of two Malaysian krait species (Bungarus candidus and Bungarus fasciatus) venoms: neutralization by monovalent and polyvalent antivenoms from Thailand.

    Science.gov (United States)

    Rusmili, Muhamad Rusdi Ahmad; Yee, Tee Ting; Mustafa, Mohd Rais; Othman, Iekhsan; Hodgson, Wayne C

    2014-03-12

    Bungarus candidus and Bungarus fasciatus are two species of krait found in Southeast Asia. Envenoming by these snakes is often characterized by neurotoxicity and, without treatment, causes considerable morbidity and mortality. In this study, the in vitro neurotoxicity of each species, and the effectiveness of two monovalent antivenoms and a polyvalent antivenom, against the neurotoxic effects of the venoms, were examined in a skeletal muscle preparation. Both venoms caused concentration-dependent inhibition of indirect twitches, and attenuated responses to exogenous nicotinic receptor agonists, in the chick biventer preparation, with B. candidus venom being more potent than B. fasciatus venom. SDS-PAGE and western blot analysis indicated different profiles between the venoms. Despite these differences, most proteins bands were recognized by all three antivenoms. Antivenom, added prior to the venoms, attenuated the neurotoxic effect of the venoms. Interestingly, the respective monovalent antivenoms did not neutralize the effects of the venom from the other Bungarus species indicating a relative absence of cross-neutralization. Addition of a high concentration of polyvalent antivenom, at the t90 time point after addition of venom, partially reversed the neurotoxicity of B. fasciatus venom but not B. candidus venom. The monovalent antivenoms had no significant effect when added at the t90 time point. This study showed that B. candidus and B. fasciatus venoms display marked in vitro neurotoxicity in the chick biventer preparation and administration of antivenoms at high dose is necessary to prevent or reverse neurotoxicity.

  15. New insights into the interactions between cork chemical components and pesticides. The contribution of π-π interactions, hydrogen bonding and hydrophobic effect.

    Science.gov (United States)

    Olivella, M À; Bazzicalupi, C; Bianchi, A; Fiol, N; Villaescusa, I

    2015-01-01

    The role of chemical components of cork in the sorption of several pesticides has been investigated. For this purpose raw cork and three cork extracted fractions (i.e. cork free of aliphatic extractives, cork free of all extractives and cork free of all extractives and suberin) were used as sorbent of three ionic pesticides (propazine, 2,4-dichlorophenoxy acetic acid (2,4-D) and alachlor) and five non-ionic pesticides (chlorpyrifos, isoproturon, metamitron, methomyl and oxamyl) with a logKow within the range -0.47 to 4.92. The effect of cations on the ionic pesticides, propazine and 2,4-D sorption was also analyzed. Results indicated that the highest yields were obtained for chlorpyrifos and alachlor sorption onto raw cork (>55%). After removal of aliphatic extractives sorption of all pesticides increased that ranged from 3% for propazine to 31% for alachlor. In contrast, removal of phenolic extractives caused a sorption decrease. Low sorption yields were obtained for hydrophobic pesticides such as metamitron, oxamyl and methomyl (cork fractions and extremely low when using raw cork (cork toward aromatic pesticides. Results presented in this paper gain insights into the cork affinities for pesticides and the interactions involved in the sorption process and also enables to envisage sorption affinity of cork for other organic pollutants.

  16. Pesticide use in Vietnamese vegetable production

    NARCIS (Netherlands)

    Hoi, P.V.; Mol, A.P.J.; Oosterveer, Peter; Brink, van den P.J.; Huong, P.T.M.

    2016-01-01

    Vietnam has had varying success over the past decade with its pesticides policy. Some of the most toxic pesticides have been banned from the market. But while many countries have successfully decreased agricultural pesticide use per hectare, this has not (yet) happened in Vietnam. Due to

  17. Theoretical study of the atrazine pesticide interaction with pyrophyllite and Ca(2+) -montmorillonite clay surfaces.

    Science.gov (United States)

    Belzunces, Bastien; Hoyau, Sophie; Benoit, Magali; Tarrat, Nathalie; Bessac, Fabienne

    2017-01-30

    Atrazine, a pesticide belonging to the s-triazine family, is one of the most employed pesticides. Due to its negative impact on the environment, it has been forbidden within the European Union since 2004 but remains abundant in soils. For these reasons, its behavior in soils and water at the atomic scale is of great interest. In this article, we have investigated, using DFT, the adsorption of atrazine onto two different clay surfaces: a pyrophyllite clay and an Mg-substituted clay named montmorillonite, with Ca(2+) compensating cations on its surface. The calculations show that the atrazine molecule is physisorbed on the pyrophyllite surface, evidencing the necessity to use dispersion-corrected computational methods. The adsorption energies of atrazine on montmorillonite are two to three times larger than on pyrophyllite, depending on the adsorption pattern. The computed adsorption energy is of about -30 kcal mol(-1) for the two most stable montmorillonite-atrazine studied isomers. For these complexes, the large adsorption energy is related to the strong interaction between the chlorine atom of the atrazine molecule and one of the Ca(2+) compensating cations of the clay surface. The structural modifications induced by the adsorption are localized: for the surface, close to substitutions and particularly below the Ca(2+) cations; in the molecule, around the chlorine atom when Ca(2+) interacts strongly with this basic site in a monodentate mode. This study shows the important role of the alkaline earth cations on the adsorption of atrazine on clays, suggesting that the atrazine pesticide retention will be significant in Ca(2+) -montmorillonite clays. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  18. Pesticide bioconcentration modelling for fruit trees.

    Science.gov (United States)

    Paraíba, Lourival Costa

    2007-01-01

    The model presented allows simulating the pesticide concentration evolution in fruit trees and estimating the pesticide bioconcentration factor in fruits. Pesticides are non-ionic organic compounds that are degraded in soils cropped with woody species, fruit trees and other perennials. The model allows estimating the pesticide uptake by plants through the water transpiration stream and also the time in which maximum pesticide concentration occur in the fruits. The equation proposed presents the relationships between bioconcentration factor (BCF) and the following variables: plant water transpiration volume (Q), pesticide transpiration stream concentration factor (TSCF), pesticide stem-water partition coefficient (K(Wood,W)), stem dry biomass (M) and pesticide dissipation rate in the soil-plant system (k(EGS)). The modeling started and was developed from a previous model "Fruit Tree Model" (FTM), reported by Trapp and collaborators in 2003, to which was added the hypothesis that the pesticide degradation in the soil follows a first order kinetic equation. The FTM model for pesticides (FTM-p) was applied to a hypothetic mango plant cropping (Mangifera indica) treated with paclobutrazol (growth regulator) added to the soil. The model fitness was evaluated through the sensitivity analysis of the pesticide BCF values in fruits with respect to the model entry data variability.

  19. Simulating pesticide transport in urbanized catchments: a new spatially-distributed dynamic pesticide runoff model

    Science.gov (United States)

    Tang, Ting; Seuntjens, Piet; van Griensven, Ann; Bronders, Jan

    2016-04-01

    Urban areas can significantly contribute to pesticide contamination in surface water. However, pesticide behaviours in urban areas, particularly on hard surfaces, are far less studied than those in agricultural areas. Pesticide application on hard surfaces (e.g. roadsides and walkways) is of particular concern due to the high imperviousness and therefore high pesticide runoff potential. Experimental studies have shown that pesticide behaviours on and interactions with hard surfaces are important factors controlling the pesticide runoff potential, and therefore the magnitude and timing of peak concentrations in surface water. We conceptualized pesticide behaviours on hard surfaces and incorporated the conceptualization into a new pesticide runoff model. The pesticide runoff model was implemented in a catchment hydrological model WetSpa-Python (Water and Energy Transfer between Soil, Plants and Atmosphere, Python version). The conceptualization for pesticide processes on hard surfaces accounts for the differences in pesticide behaviour on different hard surfaces. Four parameters are used to describe the partitioning and wash-off of each pesticide on hard surfaces. We tested the conceptualization using experimental dataset for five pesticides on two types of hard surfaces, namely concrete and asphalt. The conceptualization gave good performance in accounting for the wash-off pattern for the modelled pesticides and surfaces, according to quantitative evaluations using the Nash-Sutcliffe efficiency and percent bias. The resulting pesticide runoff model WetSpa-PST (WetSpa for PeSTicides) can simulate pesticides and their metabolites at the catchment scale. Overall, it includes four groups of pesticide processes, namely pesticide application, pesticide interception by plant foliage, pesticide processes on land surfaces (including partitioning, degradation and wash-off on hard surface; partitioning, dissipation, infiltration and runoff in soil) and pesticide processes in

  20. The Free Tricoordinated Silyl Cation Problem

    Directory of Open Access Journals (Sweden)

    Čičak, H.

    2010-03-01

    Full Text Available As the importance and abundance of silicon in our environment is large, it has been thought that silicon might take the place of carbon in forming a host of similar compounds and silicon-based life. However, until today there is no experimental evidence for such a hypothesis and carbon is still unique among the elements in the vast number and variety of compounds it can form. Also, the corresponding derivatives of the two elements show considerable differences in their chemical properties.The essential debate concerning organosilicon chemistry relates to the existence of the free planar tricoordinated silyl cations in condensed phase (R3Si+, in analogy to carbocations (R3C+ which have been known and characterized as free species. Although silyl cations are thermodynamically more stable than their carbon analogs, they are very reactive due to their high inherent electrophilicity and the ability of hypervalent coordination. On the other hand, stabilization by inductive and hyperconjugative effects and larger steric effects of carbocations make them less sensitive to solvation or other environmental effects than silyl cations. Hence, observation of free silyl cations in the condensed phase proved extremely difficult and the actual problem is the question of the degree of the (remaining silyl cation character.The first free silyl cation, trimesitylsilyl cation, and in analogy with it tridurylsilyl cation, were synthesized by Lambert et al. Free silyl cations based on analogy to aromatic ions (homocyclopropenylium and tropylium have also been prepared. However, in these silyl cations the cationic character is reduced by internal π -conjugation. Čičak et al. prepared some silyl-cationic intermediates (Me3Si--CH≡CR+in solid state. With the help of quantum-mechanical calculations it was concluded that these adducts have much more silyl cation than carbocation character.

  1. Explorations of a series of second order nonlinear optical materials based on monovalent metal gold(III) iodates.

    Science.gov (United States)

    Huang, Chao; Hu, Chun-Li; Xu, Xiang; Yang, Bing-Ping; Mao, Jiang-Gao

    2013-10-07

    The syntheses, crystal structures, and characterizations of a series of monovalent metal gold(III) iodates, namely, α-NaAu(IO3)4, β-NaAu(IO3)4, RbAu(IO3)4, α-CsAu(IO3)4, β-CsAu(IO3)4, and AgAu(IO3)4 are reported. Their structures feature Au(IO3)4(-) anions that are separated by alkali metal ions or silver(I) ions. The Au(IO3)4(-) anions in the polar α-NaAu(IO3)4, RbAu(IO3)4, and α-CsAu(IO3)4 are polar with all four iodate groups being located only above (or below) the AuO4 square plane (cis- configuration). α-NaAu(IO3)4, RbAu(IO3)4, and α-CsAu(IO3)4 display moderate strong Second-Hamonic Generation (SHG) responses of 1.17 ×, 1.33 ×, and 1.17 × KTP (KTiOPO4), respectively, and all three materials are type-I phase-matchable. The Au(IO3)4(-) anions in centrysymmetric β-NaAu(IO3)4, β-CsAu(IO3)4, and AgAu(IO3)4 are nonpolar with the four iodate groups of the Au(IO3)4(-) anion being located both above and below the AuO4 square plane (trans- configuration). IR and UV spectra, luminescent and ferroelectric properties have also been measured. Theoretical calculations of their optical properties based on density functional theory (DFT) methods were performed by using the CASTEP total-energy code.

  2. Neutralizing antibody responses in macaques induced by human immunodeficiency virus type 1 monovalent or trivalent envelope glycoproteins.

    Directory of Open Access Journals (Sweden)

    Gerald V Quinnan

    Full Text Available A major goal of efforts to develop a vaccine to prevent HIV-1 infection is induction of broadly cross-reactive neutralizing antibodies (bcnAb. In previous studies we have demonstrated induction of neutralizing antibodies that did cross-react among multiple primary and laboratory strains of HIV-1, but neutralized with limited potency. In the present study we tested the hypothesis that immunization with multiple HIV-1 envelope glycoproteins (Envs would result in a more potent and cross-reactive neutralizing response. One Env, CM243(N610Q, was selected on the basis of studies of the effects of single and multiple mutations of the four gp41 glycosylation sites. The other two Envs included R2 (subtype B and 14/00/4 (subtype F, both of which were obtained from donors with bcnAb. Rhesus monkeys were immunized using a prime boost regimen as in previous studies. Individual groups of monkeys were immunized with either one of the three Envs or all three. The single N610Q and N615Q mutations of CM243 Env did not disrupt protein secretion, processing into, or reactivity with mAbs, unlike other single or multiple deglycosylation mutations. In rabbit studies the N610Q mutation alone or in combination was associated with an enhanced neutralizing response against homologous and heterologous subtype E viruses. In the subsequent monkey study the response induced by the R2 Env regimen was equivalent to the trivalent regimen and superior to the other monovalent regimens against the virus panel used for testing. The 14/00/4 Env induced responses superior to CM243(N610Q. The results indicate that elimination of the glycosylation site near the gp41 loop results in enhanced immunogenicity, but that immunization of monkeys with these three distinct Envs was not more immunogenic than with one.

  3. Group a rotavirus and norovirus genotypes circulating in the northeastern Brazil in the post-monovalent vaccination era.

    Science.gov (United States)

    Sá, Ana Caroline C; Gómez, Mariela M; Lima, Ila Fernanda N; Quetz, Josiane S; Havt, Alexandre; Oriá, Reinaldo B; Lima, Aldo A; Leite, José Paulo G

    2015-09-01

    Group A rotaviruses (RVA) and noroviruses (NoV) are the leading cause of acute gastroenteritis (AGE) worldwide. Childhood diarrhea deaths and hospital admissions have declined since the introduction of the monovalent (G1P[8]) vaccine (Rotarix(®) [RV1]) in the National Immunization Program in Brazil in 2006. This study aims to investigate the epidemiological profile of NoV and RVA infections from children with AGE in the Northeastern region of Brazil in the post vaccine season. Two-hundred fecal samples collected from children up to 10 years old in Fortaleza, Ceará between 2008-2009 were screened for the presence of RVA and NoV. Positive samples were genotyped and sequenced. The RVA screening revealed 12% prevalence and all RVA strains belonged to G2P[4] genotype. Phylogenetic analysis based on the 11 RVA genome segments sequenced from eight samples revealed a DS-1-like genotype constellation: I2-R2-C2-M2-A2-N2-T2-E2-H2. For NoV screening, the prevalence observed was 17% and the following genotypes were detected: GII.4 (59%), GII.12 (17%), GII.6 (9%), GII.3 (6%), and GII.? (9%). At least four different NoVs genotypes and two RVA G2P[4] variants were identified circulating in the Northeastern region of Brazil. RVA phylogenetic analysis suggests that the RVA G2P[4] strains might have originated from intragenogroup reassortment events. Whether the genetic modifications observed in these contemporary G2P[4] RVA strains may impact the long-term effectiveness of the current vaccination programs remains to be explored. These data reinforce the importance of surveillance for monitoring the emergence of new strains of RVA and NoV and their impact on cases of acute gastroenteritis.

  4. Policy statement—Prevention of varicella: update of recommendations for use of quadrivalent and monovalent varicella vaccines in children.

    Science.gov (United States)

    2011-09-01

    Two varicella-containing vaccines are licensed for use in the United States: monovalent varicella vaccine (Varivax [Merck & Co, Inc, West Point, PA]) and quadrivalent measles-mumps-rubella-varicella vaccine (MMRV) (ProQuad [Merck & Co, Inc]). It is estimated from postlicensure data that after vaccination at 12 through 23 months of age, 7 to 9 febrile seizures occur per 10,000 children who receive the MMRV, and 3 to 4 febrile seizures occur per 10,000 children who receive the measles-mumps-rubella (MMR) and varicella vaccines administered concurrently but at separate sites. Thus, 1 additional febrile seizure is expected to occur per approximately 2300 to 2600 children 12 to 23 months old vaccinated with the MMRV, when compared with separate MMR and varicella vaccine administration. The period of risk for febrile seizures is from 5 through 12 days after receipt of the vaccine(s). No increased risk of febrile seizures is seen among patients 4 to 6 years of age receiving MMRV. Febrile seizures do not predispose to epilepsy or neurodevelopmental delays later in life and are not associated with long-term health impairment. The American Academy of Pediatrics recommends that either MMR and varicella vaccines separately or the MMRV be used for the first dose of measles, mumps, rubella, and varicella vaccines administered at 12 through 47 months of age. For the first dose of measles, mumps, rubella, and varicella vaccines administered at ages 48 months and older, and for dose 2 at any age (15 months to 12 years), use of MMRV generally is preferred over separate injections of MMR and varicella vaccines.

  5. Chiral Synthons in Pesticide Syntheses

    NARCIS (Netherlands)

    Feringa, Bernard

    1988-01-01

    The use of chiral synthons in the preparation of enantiomerically pure pesticides is described in this chapter. Several routes to chiral synthons based on asymmetric synthesis or on natural products are illustrated. Important sources of chiral building blocks are reviewed. Furthermore the implicatio

  6. Pesticides, People, and the Environment

    Science.gov (United States)

    Miller, Roxanne Greitz

    2005-01-01

    If a teacher were to ask his/her students what they do when they find ants or other insects in their homes, their most common response would probably be, "Get the bug spray!" Because students are not only being exposed to pesticides but are also developing patterns of behavior likely to continue throughout their lives. Discussions about…

  7. Desorption of two organophosphorous pesticides from soil with wastewater and surfactant solutions.

    Science.gov (United States)

    Hernández-Soriano, M C; Mingorance, M D; Peña, A

    2012-03-01

    A batch test was used to evaluate the extent of desorption of diazinon and dimethoate, preadsorbed on a calcareous agricultural soil, representative of the Mediterranean area. Urban wastewater from a secondary treatment and seven surfactant solutions, at concentrations ranging from 0.75 mg L(-1) to 10 gL(-1), were used. The surfactants assayed were cationic (hexadecyl trimethyl ammonium bromide (HD)), anionic (sodium dodecyl sulfate (SDS), Aerosol 22 (A22) and Biopower (BP)), and nonionic (Tween 80 (TW), Triton X 100 (TX) and Glucopon 600 (G600)). Desorption of dimethoate was either not affected or only slightly by the nonionic and anionic surfactants tested, while desorption of diazinon from the soil was only enhanced by A22, BP and TW. This desorption increase correlated significantly with the surfactant concentration of the solution used for desorption and with the concurrent increase in the supernatant of the dissolved organic carbon, in particular that originating from the surfactant. This parameter did not vary with the use of SDS, G600 and TX. The cationic surfactant HD was retained on the soil surface, as confirmed by an increase in soil organic carbon, resulting in a fall in desorption rate for both pesticides. Comparing treatment by wastewater with control water, there was no difference in desorption rate for either pesticide. Mixed TW/anionic surfactant solutions either did not modify or slightly increased desorption of both pesticides in comparison with individual surfactant solutions.

  8. The laws governing ionic liquid extraction of cations: partition of 1-ethylpyridinium monocation and paraquat dication in ionic liquid/water biphasic systems.

    Science.gov (United States)

    Hamamoto, Takuya; Okai, Miho; Katsuta, Shoichi

    2015-05-21

    To find the laws governing the extraction of cations from aqueous solutions into hydrophobic ionic liquids (ILs), we investigated the partition of 1-ethylpyridinium monocation and paraquat (1,1'-dimethyl-4,4'-bipyridinium) dication in various IL/water biphasic systems. Ten different ILs of 1-butyl-3-methylimidazolium-based or bis(trifluoromethanesulfonyl)amide-based salts were used. The distribution ratio of the target cations (T(n+)) was dependent on the initial concentration in the aqueous phase and also very sensitive to the kind of IL. The behavior was quantitatively explained on the basis of a model in which the extraction goes through both the ion exchange and ion pair transfer processes, while keeping the product of the aqueous concentrations of the IL constituent ions a constant value (solubility product, Ksp). The distribution ratio of T(n+) is expressed as a function of the difference between the initial and equilibrium concentrations of T(n+) in the aqueous phase (Δ[T(n+)]W), the aqueous solubility of IL (Ksp(1/2)), and the cation valence n. The distribution ratio is a nearly constant value (D0) when Δ[T(n+)]W ≪ Ksp(1/2)/n and decreases inversely proportional to the nth power of Δ[T(n+)]W when Δ[T(n+)]W ≫ Ksp(1/2)/n. The log D0 versus log Ksp(1/2) plot gives a linear relationship with a slope of +n for the ILs with the same anion but different cations and that with a slope of nearly -n for the ILs with the same cation but different anions. This means that the extractability dependence on the kinds of IL constituent ions is greater for the divalent cation than for the monovalent one.

  9. The Ca2+-activated cation channel TRPM4 is regulated by phosphatidylinositol 4,5-biphosphate.

    Science.gov (United States)

    Nilius, Bernd; Mahieu, Frank; Prenen, Jean; Janssens, Annelies; Owsianik, Grzegorz; Vennekens, Rudi; Voets, Thomas

    2006-02-08

    Transient receptor potential (TRP) channel, melastatin subfamily (TRPM)4 is a Ca2+-activated monovalent cation channel that depolarizes the plasma membrane and thereby modulates Ca2+ influx through Ca2+-permeable pathways. A typical feature of TRPM4 is its rapid desensitization to intracellular Ca2+ ([Ca2+]i). Here we show that phosphatidylinositol 4,5-biphosphate (PIP2) counteracts desensitization to [Ca2+]i in inside-out patches and rundown of TRPM4 currents in whole-cell patch-clamp experiments. PIP2 shifted the voltage dependence of TRPM4 activation towards negative potentials and increased the channel's Ca2+ sensitivity 100-fold. Conversely, activation of the phospholipase C (PLC)-coupled M1 muscarinic receptor or pharmacological depletion of cellular PIP2 potently inhibited currents through TRPM4. Neutralization of basic residues in a C-terminal pleckstrin homology (PH) domain accelerated TRPM4 current desensitization and strongly attenuated the effect of PIP2, whereas mutations to the C-terminal TRP box and TRP domain had no effect on the PIP2 sensitivity. Our data demonstrate that PIP2 is a strong positive modulator of TRPM4, and implicate the C-terminal PH domain in PIP2 action. PLC-mediated PIP2 breakdown may constitute a physiologically important brake on TRPM4 activity.

  10. Design of Lead-Free Inorganic Halide Perovskites for Solar Cells via Cation-Transmutation.

    Science.gov (United States)

    Zhao, Xin-Gang; Yang, Ji-Hui; Fu, Yuhao; Yang, Dongwen; Xu, Qiaoling; Yu, Liping; Wei, Su-Huai; Zhang, Lijun

    2017-02-22

    Hybrid organic-inorganic halide perovskites with the prototype material of CH3NH3PbI3 have recently attracted intense interest as low-cost and high-performance photovoltaic absorbers. Despite the high power conversion efficiency exceeding 20% achieved by their solar cells, two key issues-the poor device stabilities associated with their intrinsic material instability and the toxicity due to water-soluble Pb(2+)-need to be resolved before large-scale commercialization. Here, we address these issues by exploiting the strategy of cation-transmutation to design stable inorganic Pb-free halide perovskites for solar cells. The idea is to convert two divalent Pb(2+) ions into one monovalent M(+) and one trivalent M(3+) ions, forming a rich class of quaternary halides in double-perovskite structure. We find through first-principles calculations this class of materials have good phase stability against decomposition and wide-range tunable optoelectronic properties. With photovoltaic-functionality-directed materials screening, we identify 11 optimal materials with intrinsic thermodynamic stability, suitable band gaps, small carrier effective masses, and low excitons binding energies as promising candidates to replace Pb-based photovoltaic absorbers in perovskite solar cells. The chemical trends of phase stabilities and electronic properties are also established for this class of materials, offering useful guidance for the development of perovskite solar cells fabricated with them.

  11. Pesticides and their effects on wildlife

    Energy Technology Data Exchange (ETDEWEB)

    Driver, C.J.

    1994-07-01

    About 560 active ingredients are currently used as pesticides. Applications of these pesticides are made to agricultural lands and other areas inhabited by wildlife. Unfortunately, many agricultural-use pesticides also entail some measure of risk to organisms other than the pest species. Because testing of pesticides prior to registration cannot evaluate all the potential environmental-pesticide-wildlife/fish interactions, current methods of risk assessment do not always provide sufficient safety to nontarget organisms. This is evidenced by die-offs of fish and wildlife from applications of pesticides at environmentally {open_quotes}safe{close_quotes} rates, the linking of population declines of some species with agrochemical use, and observations of survival-threatening behavioral changes in laboratory and field animals exposed to typical field levels of pesticides. It is important to note, however, that the majority of pesticides, when properly applied, have not caused significant injury to wildlife. A brief summary of pesticide effects on wildlife and fish are presented for the common classes of pesticides in use today.

  12. Aggregation kinetics of inorganic colloids in eutrophic shallow lakes: Influence of cyanobacterial extracellular polymeric substances and electrolyte cations.

    Science.gov (United States)

    Xu, Huacheng; Yang, Changming; Jiang, Helong

    2016-12-01

    The stability/aggregation propensity of inorganic colloids in eutrophic shallow lakes is of great essence in governing the water transparency and contaminant behavior. In this study, time-resolved dynamic light scattering was employed to investigate the aggregation kinetics of Al2O3 inorganic colloids over a wide range of cyanobacterial extracellular polymeric substance (EPS) concentrations in the absence and presence of electrolyte cations. The results showed that EPS adsorption alone greatly decreased the hydrodynamic diameters of colloidal particles, whose stability behavior followed closely the predictions of the classical DLVO theory. Electrolyte cations, however, can induce the aggregation of colloidal particles, and divalent Ca(2+) were found to be more efficient in destabilizing the colloids than monovalent Na(+), as indicated by the considerably lower critical coagulation concentrations (2.5 mM for Ca(2+) vs. 170 mM for Na(+)). Further addition of Ca(2+), i.e., >2.5 mM, caused an extremely high aggregation degree and rate. High resolution transmission electron microscopy revealed that this enhanced aggregation should be attributed to the gel-like bridging between colloidal particles, which were verified to be the amorphous EPS-Ca(2+) complexes. Field-emission scanning electron microscopy coupled with elemental mapping provided additional evidence that the bridging interaction of EPS with Ca(2+) was the predominant mechanism for the aggregation enhancement. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Genome-wide identification and comparative analysis of the cation proton antiporters family in pear and four other Rosaceae species.

    Science.gov (United States)

    Zhou, Hongsheng; Qi, Kaijie; Liu, Xing; Yin, Hao; Wang, Peng; Chen, Jianqing; Wu, Juyou; Zhang, Shaoling

    2016-08-01

    The monovalent cation proton antiporters (CPAs) play essential roles in plant nutrition, development, and signal transduction by regulating ion and pH homeostasis of the cell. The CPAs of plants include the Na(+)/H(+) exchanger, K(+) efflux antiporter, and cation/H(+) exchanger families. However, currently, little is known about the CPA genes in Rosaceae species. In this study, 220 CPA genes were identified from five Rosaceae species (Pyrus bretschneideri, Malus domestica, Prunus persica, Fragaria vesca, and Prunus mume), and 53 of which came from P. bretschneideri. Phylogenetic, structure, collinearity, and gene expression analyses were conducted on the entire CPA genes of pear. Gene expression data showed that 35 and 37 CPA genes were expressed in pear fruit and pollen tubes, respectively. The transcript analysis of some CPA genes under abiotic stress conditions revealed that CPAs may play an important role in pollen tubes growth. The results presented here will be useful in improving understanding of the complexity of the CPA gene family and will promote functional characterization in future studies.

  14. The use and disposal of household pesticides.

    Science.gov (United States)

    Grey, Charlotte N B; Nieuwenhuijsen, Mark J; Golding, Jean

    2005-01-01

    Most pesticides are synthetic chemicals manufactured specifically for their toxic properties to the target species, and widely used globally. Several epidemiological studies in the United States have suggested health concerns arising from the chronic exposure of young children to pesticides in the domestic environment. In the UK very little is currently known about how nonoccupational pesticides are being used or disposed of. Any use of pesticides is a potential risk factor for children's exposure, and any potential exposure is likely to be reduced by the parents' adopting precautionary behaviour when using these pesticide products. This was investigated using a sample of 147 parents from the Avon Longitudinal Study of Parents and Children cohort in and around Bristol, through an in-depth interview between August and November 2001. The results of this study add to the understanding of the underlying behaviour of parents applying pesticide products in the home environment in the UK. Pesticides are readily available, and are normally purchased in do-it-yourself shops and supermarkets and mostly disposed of in domestic waste. Safety was stated by 45% of parents to be the most important factor to consider when buying a pesticide. When buying pesticide products, labels were stated to be the most important source of information about pesticides. However, a third of parents stated they would not follow the product label exactly when using a product, just under half felt labels were both inadequate and hard to understand, and about 10% of parents would not take notice of warnings on the pesticide label. Less than half of parents would use gloves when applying a pesticide, although the use of protective equipment such as gloves during the application of pesticides could greatly reduce the exposure. It is a public health concern that the instructions on the labels of products may not always be understood or followed, and further understanding of user behaviour is needed.

  15. Unidirectional Flux Balance of Monovalent Ions in Cells with Na/Na and Li/Na Exchange: Experimental and Computational Studies on Lymphoid U937 Cells.

    Directory of Open Access Journals (Sweden)

    Igor A Vereninov

    Full Text Available Monovalent ion traffic across the cell membrane occurs via various pathways. Evaluation of individual fluxes in whole cell is hampered by their strong interdependence. This difficulty can be overcome by computational analysis of the whole cell flux balance. However, the previous computational studies disregarded ion movement of the self-exchange type. We have taken this exchange into account. The developed software allows determination of unidirectional fluxes of all monovalent ions via the major pathways both under the balanced state and during transient processes. We show how the problem of finding the rate coefficients can be solved by measurement of monovalent ion concentrations and some of the fluxes. Interdependence of fluxes due to the mandatory conditions of electroneutrality and osmotic balance and due to specific effects can be discriminated, enabling one to identify specific changes in ion transfer machinery under varied conditions. To test the effectiveness of the developed approach we made use of the fact that Li/Na exchange is known to be an analogue of the coupled Na/Na exchange. Thus, we compared the predicted and experimental data obtained on U937 cells under varied Li+ concentrations and following inhibition of the sodium pump with ouabain. We found that the coupled Na/Na exchange in U937 cells comprises a significant portion of the entire Na+ turnover. The data showed that the loading of the sodium pump by Li/Na exchange involved in the secondary active Li+ transport at 1-10 mM external Li+ is small. This result may be extrapolated to similar Li+ and Na+ flux relationships in erythrocytes and other cells in patients treated with Li+ in therapeutic doses. The developed computational approach is applicable for studying various cells and can be useful in education for demonstrating the effects of individual transporters and channels on ion gradients, cell water content and membrane potential.

  16. Unidirectional Flux Balance of Monovalent Ions in Cells with Na/Na and Li/Na Exchange: Experimental and Computational Studies on Lymphoid U937 Cells.

    Science.gov (United States)

    Vereninov, Igor A; Yurinskaya, Valentina E; Model, Michael A; Vereninov, Alexey A

    2016-01-01

    Monovalent ion traffic across the cell membrane occurs via various pathways. Evaluation of individual fluxes in whole cell is hampered by their strong interdependence. This difficulty can be overcome by computational analysis of the whole cell flux balance. However, the previous computational studies disregarded ion movement of the self-exchange type. We have taken this exchange into account. The developed software allows determination of unidirectional fluxes of all monovalent ions via the major pathways both under the balanced state and during transient processes. We show how the problem of finding the rate coefficients can be solved by measurement of monovalent ion concentrations and some of the fluxes. Interdependence of fluxes due to the mandatory conditions of electroneutrality and osmotic balance and due to specific effects can be discriminated, enabling one to identify specific changes in ion transfer machinery under varied conditions. To test the effectiveness of the developed approach we made use of the fact that Li/Na exchange is known to be an analogue of the coupled Na/Na exchange. Thus, we compared the predicted and experimental data obtained on U937 cells under varied Li+ concentrations and following inhibition of the sodium pump with ouabain. We found that the coupled Na/Na exchange in U937 cells comprises a significant portion of the entire Na+ turnover. The data showed that the loading of the sodium pump by Li/Na exchange involved in the secondary active Li+ transport at 1-10 mM external Li+ is small. This result may be extrapolated to similar Li+ and Na+ flux relationships in erythrocytes and other cells in patients treated with Li+ in therapeutic doses. The developed computational approach is applicable for studying various cells and can be useful in education for demonstrating the effects of individual transporters and channels on ion gradients, cell water content and membrane potential.

  17. Afrikaans Syllabification Patterns

    Directory of Open Access Journals (Sweden)

    Tilla Fick

    2010-01-01

    Full Text Available In contrast to English, automatic hyphenation by computer of Afrikaans words is a problem that still needs to be addressed, since errors are still often encountered in printed text. An initial step in this task is the ability to automatically syllabify words. Since new words are created continuously by joining words, it is necessary to develop an “intelligent” technique for syllabification. As a first phase of the research, we consider only the orthographic information of words, and disregard both syntactic and morphological information. This approach allows us to use machine-learning techniques such as artificial neural networks and decision trees that are known for their pattern recognition abilities. Both these techniques are trained with isolated patterns consisting of input patterns and corresponding outputs (or targets that indicate whether the input pattern should be split at a certain position, or not. In the process of compiling a list of syllabified words from which to generate training data for the  syllabification problem, irregular patterns were identified. The same letter patterns are split differently in different words and complete words that are spelled identically are split differently due to meaning. We also identified irregularities in and between  the different dictionaries that we used. We examined the influence range of letters that are involved in irregularities. For example, for their in agter-ente and vaste-rente we have to consider three letters to the left of r to be certain where the hyphen should be inserted. The influence range of the k in verstek-waarde and kleinste-kwadrate is four to the left and three to the right. In an analysis of letter patterns in Afrikaans words we found that the letter e has the highest frequency overall (16,2% of all letters in the word list. The frequency of words starting with s is the highest, while the frequency of words ending with e is the highest. It is important to

  18. [Acute toxicity of different type pesticide surfactants to Daphnia magna].

    Science.gov (United States)

    Li, Xiu-huan; Li, Hua; Chen, Cheng-yu; Li, Jian-tao; Liu, Feng

    2013-08-01

    By using the standard test methods in Experimental Guideline for Environmental Safety Evaluation of Chemical Pesticide to aquatic organisms, a comparative study was conducted on the acute toxicity of 39 nonionic, 6 anionic, and 3 cationic surfactants to Daphnia magna. The acute toxicity of three cationic surfactants 1427, 1227 and C8-10 to D. magna belonged to virulent level, and the toxicity of 1427 was the highest, with the EC50 value being 0.97 x 10(-2) mg x L(-1). The acute toxicity of nonionic surfactants polyoxyethylene ether castor oil EL, Tween, and Span emulsifiers belonged to low level, but the toxicity of alkylphenol polyoxyethylene ether and fatty alcohol polyoxyethylene ether surfactants was relatively high, of which, AEO-7 and AEO-5 displayed high toxicity, with the EC50 value being 0.82 and 0.97 mg x L(-1), respectively. In these surfactants, the more liposolubility, the higher the toxicity was. Most of the anionic surfactants were medium in toxicity, but the acute toxicity of NNO belonged to high toxicity, with the EC50 value being 0.17 mg x L(-1).

  19. Assessment of epicutaneous testing of a monovalent Influenza A (H1N1 2009 vaccine in egg allergic patients

    Directory of Open Access Journals (Sweden)

    Pitt Tracy

    2011-02-01

    Full Text Available Abstract Background H1N1 is responsible for the first influenza pandemic in 41 years. In the fall of 2009, an H1N1 vaccine became available in Canada with the hopes of reducing the overall effect of the pandemic. The purpose of this study was to assess the safety of administering 2 different doses of a monovalent split virus 2009 H1N1 vaccine in egg allergic patients. Methods Patients were skin tested to the H1N1 vaccine in the outpatient paediatric and adult allergy and immunology clinics of the Health Sciences Centre and Children's Hospital of Winnipeg, Manitoba Canada. Individuals Results A total of 61 patients with egg allergy (history of an allergic reaction to egg with either positive skin test &/or specific IgE to egg >0.35 Ku/L were referred to our allergy clinics for skin testing to the H1N1 vaccine. 2 patients were excluded, one did not have a skin prick test to the H1N1 vaccine (only vaccine administration and the other passed an egg challenge during the study period. Ages ranged from 1 to 27 years (mean 5.6 years. There were 41(69.5% males and 18(30.5% females. All but one patient with a history of egg allergy, positive skin test to egg and/or elevated specific IgE level to egg had negative skin tests to the H1N1 vaccine. The 58 patients with negative skin testing to the H1N1 vaccine were administered the vaccine and observed for 30 minutes post vaccination with no adverse results. The patient with the positive skin test to the H1N1 vaccine was also administered the vaccine intramuscularly with no adverse results. Conclusions Despite concern regarding possible anaphylaxis to the H1N1 vaccine in egg allergic patients, in our case series 1/59(1.7% patients with sensitization to egg were also sensitized to the H1N1 vaccine. Administration of the H1N1 vaccine in egg allergic patients with negative H1N1 skin tests and observation is safe. Administering the vaccine in a 1 or 2 dose protocol without skin testing is a reasonable alternative

  20. Fate of pesticides during beer brewing.

    Science.gov (United States)

    Inoue, Tomonori; Nagatomi, Yasushi; Suga, Keiko; Uyama, Atsuo; Mochizuki, Naoki

    2011-04-27

    The fates of more than 300 pesticide residues were investigated in the course of beer brewing. Ground malt artificially contaminated with pesticides was brewed via steps such as mashing, boiling, and fermentation. Analytical samples were taken from wort, spent grain, and beer produced at certain key points in the brewing process. The samples were extracted and purified with the QuEChERS (Quick Easy Cheap Effective Rugged and Safe) method and were then analyzed by LC-MS/MS using a multiresidue method. In the results, a majority of pesticides showed a reduction in the unhopped wort and were adsorbed onto the spent grain after mashing. In addition, some pesticides diminished during the boiling and fermentation. This suggests that the reduction was caused mainly by adsorption, pyrolysis, and hydrolysis. After the entire process of brewing, the risks of contaminating beer with pesticides were reduced remarkably, and only a few pesticides remained without being removed or resolved.

  1. AFFINITY OF THE ALLIGATOR ESTROGEN RECEPTOR FOR SERUM PESTICIDE CONTAMINANTS

    Science.gov (United States)

    Top predators, like the American alligator (Alligator mississippiensis) bioaccumulate and biomagnify persistent pollutants, such as organochlorine pesticides. In a recently published study, several pesticides and pesticide metabolites not previously reported in alligator eggs wer...

  2. A mobile App for military operational entomology pesticide applications

    Science.gov (United States)

    Multiple field studies conducted for the Deployed War Fighter Protection (DWFP) research program have generated over 80 specific guidance points for innovative combinations of pesticide application equipment, pesticide formulations, and application techniques for aerosol and residual pesticide treat...

  3. Pesticide knowledge, practice and attitude and how it affects the ...

    African Journals Online (AJOL)

    2014-06-02

    Jun 2, 2014 ... reduce negative health effects of pesticides in humans and prevent pesticide .... young current or recently graduated Ugandan students from Makerere ...... pesticides on Tanzanian small-scale coffee growers. J. Expo Anal ...

  4. Citizen's Guide to Pest Control and Pesticide Safety

    Science.gov (United States)

    Teaches consumers how to control pests, choose, use, store, and dispose pesticides safely, reduce exposure when others use pesticides, prevent pesticide poisoning, handle an emergency, and how to choose a pest control company.

  5. 40 CFR 158.2080 - Experimental use permit data requirements-biochemical pesticides.

    Science.gov (United States)

    2010-07-01

    ... requirements-biochemical pesticides. 158.2080 Section 158.2080 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Biochemical Pesticides § 158.2080 Experimental use permit data requirements—biochemical pesticides. (a) Sections...

  6. The enzymatic basis for pesticide bioremediation

    OpenAIRE

    Scott, Colin; Pandey, Gunjan; Hartley, Carol J.; Jackson, Colin J.; Cheesman, Matthew J.; Taylor, Matthew C.; Pandey, Rinku; Khurana, Jeevan L.; Teese, Mark; Coppin, Chris W; Weir, Kahli M.; Jain, Rakesh K.; Lal, Rup; Russell, Robyn J.; Oakeshott, John G.

    2008-01-01

    Enzymes are central to the biology of many pesticides, influencing their modes of action, environmental fates and mechanisms of target species resistance. Since the introduction of synthetic xenobiotic pesticides, enzymes responsible for pesticide turnover have evolved rapidly, in both the target organisms and incidentally exposed biota. Such enzymes are a source of significant biotechnological potential and form the basis of several bioremediation strategies intended to reduce the environmen...

  7. Effect of Endocrine Disruptor Pesticides: A Review

    OpenAIRE

    Benoit Roig; Olivier Thomas; Aghleb Bartegi; Wissem Mnif; Aicha Bouaziz; Aziza Ibn Hadj Hassine

    2011-01-01

    International audience; Endocrine disrupting chemicals (EDC) are compounds that alter the normal functioning of the endocrine system of both wildlife and humans. A huge number of chemicals have been identified as endocrine disruptors, among them several pesticides. Pesticides are used to kill unwanted organisms in crops, public areas, homes and gardens, and parasites in medicine. Human are exposed to pesticides due to their occupations or through dietary and environmental exposure (water, soi...

  8. Pesticide burial grounds in Poland: a review.

    Science.gov (United States)

    Gałuszka, Agnieszka; Migaszewski, Zdzisław M; Manecki, Piotr

    2011-10-01

    Obsolete pesticides were stored in Poland from the middle sixties until the late eighties of the 20th century mostly in underground disposal sites, called "pesticide burial grounds" or "pesticide tombs". The total amount of pesticide waste and packaging materials disposed of in these landfills exceeded 20000 Mg. Typically, the content of a pesticide tomb was dominated by organochlorine pesticides (comprising 10-100% of the total waste volume) with DDT as the prevailing compound. Other pesticide types, such as phosphoroorganic, carbamate insecticides, dinitrophenols, phenoxyacids, and inorganic compounds were stored in smaller quantities, usually not exceeding 10-20% of the total waste volume. With the growing awareness of the threats that these landfills posed to the environment, the first inventory for the whole country was made in 1993 and remediation was initiated in 1999. The total amount of waste, which had to be removed from the known pesticide tombs (hazardous substances, contaminated soils, construction materials etc.) was about 100000 Mg. According to the National Waste Management Plan, the reclamation of pesticide tombs was assumed to have been finished by the end of 2010, however, this goal has not been achieved. The aim of this review is to present a historical perspective of pesticide burial grounds in Poland with an emphasis on their creation, function, inventory, and remediation. Based on unpublished reports, and other published materials of limited availability written in Polish, this review may serve as a source of information for representatives of other countries, where remediation of pesticide burial grounds is still in progress. The experience gained over a ten-year period, when restoration of pesticide tombs was implemented in Poland, reveals that there are many obstacles to this action arising not only from technical, but also from economic and social issues.

  9. Genetic Alterations in Pesticide Exposed Bolivian Farmers

    OpenAIRE

    J?rs, Erik; Gonz?les, Ana Rosa; Ascarrunz, Maria Eugenia; Tirado, Noemi; Takahashi, Catharina; Lafuente, Erika; dos Santos, Raquel A.; Bailon, Natalia; Cervantes, Rafael; O, Huici; B?lum, Jesper; Lander, Flemming

    2007-01-01

    Background Pesticides are of concern in Bolivia because of increasing use. Frequent intoxications have been demonstrated due to use of very toxic pesticides, insufficient control of distribution and sale and little knowledge among farmers of protective measures and hygienic procedures. Method Questionnaires were applied and blood tests taken from 81 volunteers from La Paz County, of whom 48 were pesticide exposed farmers and 33 non-exposed controls. Sixty males and 21 females participated wit...

  10. Advancements in Anion Exchange Membrane Cations

    Energy Technology Data Exchange (ETDEWEB)

    Sturgeon, Matthew R. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Long, Hai [National Renewable Energy Lab. (NREL), Golden, CO (United States); Park, Andrew M. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Pivovar, Bryan S. [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2015-10-15

    Anion-exchange membrane fuel cells (AME-FCs) are of increasingly popular interest as they enable the use of non-Pt fuel cell catalysts, the primary cost limitation of proton exchange membrane fuel cells. Benzyltrimethyl ammonium (BTMA) is the standard cation that has historically been utilized as the hydroxide conductor in AEMs. Herein we approach AEMs from two directions. First and foremost we study the stability of several different cations in a hydroxide solution at elevated temperatures. We specifically targeted BTMA and methoxy and nitro substituted BTMA. We've also studied the effects of adding an akyl spacer units between the ammonium cation and the phenyl group. In the second approach we use computational studies to predict stable ammonium cations, which are then synthesized and tested for stability. Our unique method to study cation stability in caustic conditions at elevated temperatures utilizes Teflon Parr reactors suitable for use under various temperatures and cation concentrations. NMR analysis was used to determine remaining cation concentrations at specific time points with GCMS analysis verifying product distribution. We then compare the experimental results with calculated modeling stabilities. Our studies show that the electron donating methoxy groups slightly increase stability (compared to that of BTMA), while the electron withdrawing nitro groups greatly decrease stability in base. These results give insight into possible linking strategies to be employed when tethering a BTMA like ammonium cation to a polymeric backbone; thus synthesizing an anion exchange membrane.

  11. 75 FR 74673 - Pesticides; Regulation To Clarify Labeling of Pesticides for Export; Notification to the...

    Science.gov (United States)

    2010-12-01

    ... AGENCY 40 CFR Part 168 RIN 2070-AJ53 Pesticides; Regulation To Clarify Labeling of Pesticides for Export...(a) of the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA). As described in the Agency's... specificity to existing labeling regulations for the export of unregistered pesticide products and...

  12. Pesticides: Benefaction or Pandora's Box? A synopsis of the environmental aspects of 243 pesticides

    NARCIS (Netherlands)

    Linders JBHJ; Jansma JW; Mensink BJWG; Otermann K; ACT

    1994-01-01

    The report provides an overview of physical, chemical and environmental data of 243 pesticides. The data mentioned are based on confidential information supplied by the manufacturers of the pesticides. For all pesticides mentioned a Final Environmental File, which is public, is derived. Tables with

  13. Analytical methods for detecting pesticide switches with evolution of pesticide resistance.

    Science.gov (United States)

    Liang, Juhua; Tang, Sanyi; Nieto, Juan J; Cheke, Robert A

    2013-10-01

    After a pest develops resistance to a pesticide, switching between different unrelated pesticides is a common management option, but this raises the following questions: (1) What is the optimal frequency of pesticide use? (2) How do the frequencies of pesticide applications affect the evolution of pesticide resistance? (3) How can the time when the pest population reaches the economic injury level (EIL) be estimated and (4) how can the most efficient frequency of pesticide applications be determined? To address these questions, we have developed a novel pest population growth model incorporating the evolution of pesticide resistance and pulse spraying of pesticides. Moreover, three pesticide switching methods, threshold condition-guided, density-guided and EIL-guided, are modelled, to determine the best choice under different conditions with the overall aim of eradicating the pest or maintaining its population density below the EIL. Furthermore, the pest control outcomes based on those three pesticide switching methods are discussed. Our results suggest that either the density-guided or EIL-guided method is the optimal pesticide switching strategy, depending on the frequency (or period) of pesticide applications.

  14. 75 FR 33705 - Pesticide Management and Disposal; Standards for Pesticide Containers and Containment; Change to...

    Science.gov (United States)

    2010-06-15

    ... AGENCY 40 CFR Part 156 RIN 2070-AJ74 Pesticide Management and Disposal; Standards for Pesticide Containers and Containment; Change to Labeling Compliance Date AGENCY: Environmental Protection Agency (EPA... December 16, 2010. This change is being made because there is insufficient time for pesticide registrants...

  15. Pesticides: Benefaction or Pandora's Box? A synopsis of the environmental aspects of 243 pesticides

    NARCIS (Netherlands)

    Linders JBHJ; Jansma JW; Mensink BJWG; Otermann K; ACT

    1994-01-01

    The report provides an overview of physical, chemical and environmental data of 243 pesticides. The data mentioned are based on confidential information supplied by the manufacturers of the pesticides. For all pesticides mentioned a Final Environmental File, which is public, is derived. Tables with

  16. 77 FR 64990 - Pesticide Program Dialogue Committee; Request for Nominations to the Pesticide Program Dialogue...

    Science.gov (United States)

    2012-10-24

    ... AGENCY Pesticide Program Dialogue Committee; Request for Nominations to the Pesticide Program Dialogue... Pesticide Program Dialogue Committee (PPDC). EPA values and welcomes diversity. In an effort to obtain... American food supply, the education and protection from unreasonable risk of those who apply or are...

  17. 75 FR 13284 - Pesticide Program Dialogue Committee; Request for Nominations to the Pesticide Program Dialogue...

    Science.gov (United States)

    2010-03-19

    ... AGENCY Pesticide Program Dialogue Committee; Request for Nominations to the Pesticide Program Dialogue... to be considered for appointment to the Pesticide Program Dialogue Committee (PPDC). EPA values and... American food supply, the education and protection from unreasonable risk of those who apply or are...

  18. Effect of Endocrine Disruptor Pesticides: A Review

    Directory of Open Access Journals (Sweden)

    Benoit Roig

    2011-06-01

    Full Text Available Endocrine disrupting chemicals (EDC are compounds that alter the normal functioning of the endocrine system of both wildlife and humans. A huge number of chemicals have been identified as endocrine disruptors, among them several pesticides. Pesticides are used to kill unwanted organisms in crops, public areas, homes and gardens, and parasites in medicine. Human are exposed to pesticides due to their occupations or through dietary and environmental exposure (water, soil, air. For several years, there have been enquiries about the impact of environmental factors on the occurrence of human pathologies. This paper reviews the current knowledge of the potential impacts of endocrine disruptor pesticides on human health.

  19. Effect of endocrine disruptor pesticides: a review.

    Science.gov (United States)

    Mnif, Wissem; Hassine, Aziza Ibn Hadj; Bouaziz, Aicha; Bartegi, Aghleb; Thomas, Olivier; Roig, Benoit

    2011-06-01

    Endocrine disrupting chemicals (EDC) are compounds that alter the normal functioning of the endocrine system of both wildlife and humans. A huge number of chemicals have been identified as endocrine disruptors, among them several pesticides. Pesticides are used to kill unwanted organisms in crops, public areas, homes and gardens, and parasites in medicine. Human are exposed to pesticides due to their occupations or through dietary and environmental exposure (water, soil, air). For several years, there have been enquiries about the impact of environmental factors on the occurrence of human pathologies. This paper reviews the current knowledge of the potential impacts of endocrine disruptor pesticides on human health.

  20. Occupational pesticide exposures and respiratory health.

    Science.gov (United States)

    Ye, Ming; Beach, Jeremy; Martin, Jonathan W; Senthilselvan, Ambikaipakan

    2013-11-28

    Pesticides have been widely used to control pest and pest-related diseases in agriculture, fishery, forestry and the food industry. In this review, we identify a number of respiratory symptoms and diseases that have been associated with occupational pesticide exposures. Impaired lung function has also been observed among people occupationally exposed to pesticides. There was strong evidence for an association between occupational pesticide exposure and asthma, especially in agricultural occupations. In addition, we found suggestive evidence for a link between occupational pesticide exposure and chronic bronchitis or COPD. There was inconclusive evidence for the association between occupational pesticide exposure and lung cancer. Better control of pesticide uses and enforcement of safety behaviors, such as using personal protection equipment (PPE) in the workplace, are critical for reducing the risk of developing pesticide-related symptoms and diseases. Educational training programs focusing on basic safety precautions and proper uses of personal protection equipment (PPE) are possible interventions that could be used to control the respiratory diseases associated with pesticide exposure in occupational setting.

  1. Effect of Endocrine Disruptor Pesticides: A Review

    Science.gov (United States)

    Mnif, Wissem; Hassine, Aziza Ibn Hadj; Bouaziz, Aicha; Bartegi, Aghleb; Thomas, Olivier; Roig, Benoit

    2011-01-01

    Endocrine disrupting chemicals (EDC) are compounds that alter the normal functioning of the endocrine system of both wildlife and humans. A huge number of chemicals have been identified as endocrine disruptors, among them several pesticides. Pesticides are used to kill unwanted organisms in crops, public areas, homes and gardens, and parasites in medicine. Human are exposed to pesticides due to their occupations or through dietary and environmental exposure (water, soil, air). For several years, there have been enquiries about the impact of environmental factors on the occurrence of human pathologies. This paper reviews the current knowledge of the potential impacts of endocrine disruptor pesticides on human health. PMID:21776230

  2. Occupational Pesticide Exposures and Respiratory Health

    Directory of Open Access Journals (Sweden)

    Ming Ye

    2013-11-01

    Full Text Available Pesticides have been widely used to control pest and pest-related diseases in agriculture, fishery, forestry and the food industry. In this review, we identify a number of respiratory symptoms and diseases that have been associated with occupational pesticide exposures. Impaired lung function has also been observed among people occupationally exposed to pesticides. There was strong evidence for an association between occupational pesticide exposure and asthma, especially in agricultural occupations. In addition, we found suggestive evidence for a link between occupational pesticide exposure and chronic bronchitis or COPD. There was inconclusive evidence for the association between occupational pesticide exposure and lung cancer. Better control of pesticide uses and enforcement of safety behaviors, such as using personal protection equipment (PPE in the workplace, are critical for reducing the risk of developing pesticide-related symptoms and diseases. Educational training programs focusing on basic safety precautions and proper uses of personal protection equipment (PPE are possible interventions that could be used to control the respiratory diseases associated with pesticide exposure in occupational setting.

  3. Sorption of pesticides to aquifer minerals

    DEFF Research Database (Denmark)

    Clausen, Liselotte; Fabricius, Ida Lykke

    2000-01-01

    This paper summarizes results from a work were the sorption of five pesticides on seven minerals were studied in order to quantify the adsorption to different mineral surfaces. Investigated mineral phases are: quartz, calcite, kaolinite, a-alumina, and three iron oxides (2-line ferrihydrite, goet......, goethite, lepidocrocite). Selected pesticides are: atrazine, isoproturon, mecoprop, 2,4-D, and bentazone. The results demonstrate that pesticides adsorb to pure mineral surfaces. However, the size of the adsorption depends on the type of pesticide and the type of mineral....

  4. Cation diffusion in the natural zeolite clinoptilolite

    Energy Technology Data Exchange (ETDEWEB)

    Dyer, A.; White, K.J. [Science Research Institute, Chemistry Division, Cockcroft Building, University of Salford, Salford (United Kingdom)

    1999-12-14

    The natural zeolite clinoptilolite is mined commercially in many parts of the world. It is a selective exchanger for the ammonium cation and this has prompted its use in waste water treatment, swimming pools and in fish farming. It is also used to scavenge radioisotopes in nuclear waste clean-up. Further potential uses for clinoptilolite are in soil amendment and remediation. The work described herein provides thermodynamic data on cation exchange processes in clinoptilolite involving the NH{sub 4}, Na, K, Ca, and Mg cations. The data includes estimates of interdiffusion coefficients together with free energies, entropies and energies of activation for the cation exchanges studied. Suggestions are made as to the mechanisms of cation-exchanges involved.

  5. Cationic Bolaamphiphiles for Gene Delivery

    Science.gov (United States)

    Tan, Amelia Li Min; Lim, Alisa Xue Ling; Zhu, Yiting; Yang, Yi Yan; Khan, Majad

    2014-05-01

    Advances in medical research have shed light on the genetic cause of many human diseases. Gene therapy is a promising approach which can be used to deliver therapeutic genes to treat genetic diseases at its most fundamental level. In general, nonviral vectors are preferred due to reduced risk of immune response, but they are also commonly associated with low transfection efficiency and high cytotoxicity. In contrast to viral vectors, nonviral vectors do not have a natural mechanism to overcome extra- and intracellular barriers when delivering the therapeutic gene into cell. Hence, its design has been increasingly complex to meet challenges faced in targeting of, penetration of and expression in a specific host cell in achieving more satisfactory transfection efficiency. Flexibility in design of the vector is desirable, to enable a careful and controlled manipulation of its properties and functions. This can be met by the use of bolaamphiphile, a special class of lipid. Unlike conventional lipids, bolaamphiphiles can form asymmetric complexes with the therapeutic gene. The advantage of having an asymmetric complex lies in the different purposes served by the interior and exterior of the complex. More effective gene encapsulation within the interior of the complex can be achieved without triggering greater aggregation of serum proteins with the exterior, potentially overcoming one of the great hurdles faced by conventional single-head cationic lipids. In this review, we will look into the physiochemical considerations as well as the biological aspects of a bolaamphiphile-based gene delivery system.

  6. Pesticide poisoning in the developing world--a minimum pesticides list

    DEFF Research Database (Denmark)

    Eddleston, Michael; Karalliedde, Lakshman; Buckley, Nick

    2002-01-01

    In parts of the developing world, pesticide poisoning causes more deaths than infectious diseases. Use of pesticides is poorly regulated and often dangerous; their easy availability also makes them a popular method of self-harm. In 1985, the UN Food and Agriculture Organisation (FAO) produced...... pesticides be restricted--where this has been done, suicide rates have fallen. Since an Essential Drugs List was established in 1977, use of a few essential drugs has rationalised drug use in many regions. An analogous Minimum Pesticides List would identify a restricted number of less dangerous pesticides...... a voluntary code of conduct for the pesticide industry in an attempt to limit the harmful effects of pesticides. Unfortunately, a lack of adequate government resources in the developing world makes this code ineffective, and thousands of deaths continue today. WHO has recommended that access to highly toxic...

  7. Pattern of pesticide storage before pesticide self-poisoning in rural Sri Lanka

    DEFF Research Database (Denmark)

    Mohamed, Fahim; Manuweera, Gamini; Gunnell, David

    2009-01-01

    BACKGROUND: Deliberate self-poisoning with agricultural pesticides is the commonest means of suicide in rural Asia. It is mostly impulsive and facilitated by easy access to pesticides. The aim of this large observational study was to investigate the immediate source of pesticides used for self......-harm to help inform suicide prevention strategies such as reducing domestic access to pesticides. METHODS: The study was conducted in a district hospital serving an agricultural region of Sri Lanka. Patients who had self-poisoned with pesticides and were admitted to the adult medical wards were interviewed...... by study doctors following initial resuscitation to identify the source of pesticides they have ingested. RESULTS: Of the 669 patients included in the analysis, 425 (63.5%) were male; the median age was 26 (IQR 20-36). In 511 (76%) cases, the pesticides had been stored either inside or immediately outside...

  8. Cation distributions on rapidly solidified cobalt ferrite

    Science.gov (United States)

    De Guire, Mark R.; Kalonji, Gretchen; O'Handley, Robert C.

    1990-01-01

    The cation distributions in two rapidly solidified cobalt ferrites have been determined using Moessbauer spectroscopy at 4.2 K in an 8-T magnetic field. The samples were obtained by gas atomization of a Co0-Fe2O3-P2O5 melt. The degree of cation disorder in both cases was greater than is obtainable by cooling unmelted cobalt ferrite. The more rapidly cooled sample exhibited a smaller departure from the equilibrium cation distribution than did the more slowly cooled sample. This result is explained on the basis of two competing effects of rapid solidification: high cooling rate of the solid, and large undercooling.

  9. Cation distributions on rapidly solidified cobalt ferrite

    Science.gov (United States)

    De Guire, Mark R.; Kalonji, Gretchen; O'Handley, Robert C.

    1990-01-01

    The cation distributions in two rapidly solidified cobalt ferrites have been determined using Moessbauer spectroscopy at 4.2 K in an 8-T magnetic field. The samples were obtained by gas atomization of a Co0-Fe2O3-P2O5 melt. The degree of cation disorder in both cases was greater than is obtainable by cooling unmelted cobalt ferrite. The more rapidly cooled sample exhibited a smaller departure from the equilibrium cation distribution than did the more slowly cooled sample. This result is explained on the basis of two competing effects of rapid solidification: high cooling rate of the solid, and large undercooling.

  10. Pesticide biotransformation and fate in heterogeneous environments

    NARCIS (Netherlands)

    Vink, J.P.M.

    1997-01-01

    The effects and relative impacts of environmental variables on the behaviour of pesticides, through the effect on pesticide-degrading microorganisms, was studied in a broad spectrum and covered the most relevant emission routes. It is shown that the effect of landscape geochemistry, which i

  11. Aquatic Macrophyte Risk Assessment for Pesticides

    NARCIS (Netherlands)

    Maltby, L.; Arnold, D.; Arts, G.H.P.; Davies, J.; Heimbach, F.; Pickl, C.; Poulsen, V.

    2009-01-01

    Given the essential role that primary producers play in aquatic ecosystems, it is imperative that the potential risk of pesticides to the structure and functioning of aquatic plants is adequately assessed. This book discusses the assessment of the risk of pesticides with herbicidal activity to

  12. Pesticide biotransformation and fate in heterogeneous environments.

    NARCIS (Netherlands)

    Vink, J.P.M.

    1997-01-01

    The effects and relative impacts of environmental variables on the behaviour of pesticides, through the effect on pesticide-degrading microorganisms, was studied in a broad spectrum and covered the most relevant emission routes. It is shown that the effect of landscape geochemistry, which is a pre-s

  13. 75 FR 6656 - Pesticide Product; Registration Application

    Science.gov (United States)

    2010-02-10

    ... AGENCY Pesticide Product; Registration Application AGENCY: Environmental Protection Agency (EPA). ACTION: Notice. SUMMARY: This notice announces receipt of an application to register a new use for a pesticide... the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA), as amended. EPA is publishing...

  14. 78 FR 53682 - Tetrachlorvinphos; Pesticide Tolerances

    Science.gov (United States)

    2013-08-30

    ... AGENCY 40 CFR Part 180 Tetrachlorvinphos; Pesticide Tolerances AGENCY: Environmental Protection Agency... by converting them to permanent tolerances for the combined residues of the insecticide...-OPP-2011-0360, is available at http://www.regulations.gov or at the Office of Pesticide...

  15. 75 FR 56105 - Pesticide Products; Registration Applications

    Science.gov (United States)

    2010-09-15

    ... AGENCY Pesticide Products; Registration Applications AGENCY: Environmental Protection Agency (EPA). ACTION: Notice. SUMMARY: This notice announces receipt of applications to register new uses for pesticide... notice of such applications, pursuant to section 3(c)(4) of FIFRA. DATES: Comments must be received on or...

  16. 75 FR 76463 - Pesticide Products; Registration Applications

    Science.gov (United States)

    2010-12-08

    ... AGENCY Pesticide Products; Registration Applications AGENCY: Environmental Protection Agency (EPA). ACTION: Notice. SUMMARY: This notice announces receipt of applications to register new uses for pesticide... Notice of such applications, pursuant to section 3(c)(4) of FIFRA. ] DATES: Comments must be received on...

  17. 76 FR 17645 - Pesticide Products; Registration Applications

    Science.gov (United States)

    2011-03-30

    ... AGENCY Pesticide Products; Registration Applications AGENCY: Environmental Protection Agency (EPA). ACTION: Notice. SUMMARY: EPA has received an application to register a pesticide product containing the... on this application. DATES: Comments must be received on or before April 29, 2011. ADDRESSES: Submit...

  18. The impact of pesticides on male fertility.

    NARCIS (Netherlands)

    Roeleveld, N.; Bretveld, R.

    2008-01-01

    PURPOSE OF REVIEW: Observations in several Western countries point toward a decline in semen quality which may be associated with exposure to environmental endocrine disruptors such as several frequently used pesticides. The scarce literature on the effects of pesticides on male fertility will be re

  19. Aquatic Macrophyte Risk Assessment for Pesticides

    NARCIS (Netherlands)

    Maltby, L.; Arnold, D.; Arts, G.H.P.; Davies, J.; Heimbach, F.; Pickl, C.; Poulsen, V.

    2009-01-01

    Given the essential role that primary producers play in aquatic ecosystems, it is imperative that the potential risk of pesticides to the structure and functioning of aquatic plants is adequately assessed. This book discusses the assessment of the risk of pesticides with herbicidal activity to aquat

  20. 33 CFR 274.4 - Pesticide management.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Pesticide management. 274.4... DEFENSE PEST CONTROL PROGRAM FOR CIVIL WORKS PROJECTS Project Operation § 274.4 Pesticide management. (a... control management personnel prior to advertisement of the contract and procurement of services....

  1. Occupational pesticide exposure among Kenyan agricultural workers.

    NARCIS (Netherlands)

    Ohayo-Mitoko, G.J.A.

    1997-01-01

    This study was part of the Kenyan component of a multi-centre epidemiologic survey, the East African Pesticides Project. The general objective was to assess the health hazards posed by pesticide handling, storage and use in agricultural estates and small farms in selected rural agricultural communit

  2. Genetic Alterations in Pesticide Exposed Bolivian Farmers

    DEFF Research Database (Denmark)

    Jørs, Erik; González, Ana Rosa; Ascarrunz, Maria Eugenia

    2007-01-01

    Background: Pesticides are of concern in Bolivia because of increasing use. Frequent intoxications have been demonstrated due to use of very toxic pesticides, insufficient control of distribution and sale and little knowledge among farmers of protective measures and hygienic procedures. Method: Q...

  3. EPA Regulation of Bed Bug Pesticides

    Science.gov (United States)

    All pesticides must be registered by EPA before being sold and used in the U.S., other than those that rely on a limited set of active ingredients (so-called minimum risk pesticides). EPA reviews for safety and effectiveness.

  4. Carbamate pesticide induced toxic epidermal necrolysis

    Directory of Open Access Journals (Sweden)

    Rajendran N

    2001-09-01

    Full Text Available A 36-year-old male alleged to have consumed carbamate pesticide liquid (Baygon@ developed toxic epidermal necrolysis (TEN within twenty-four hours of intake. Though drugs have been commonly incriminated as offending agents for TEN, carbamate pesticide was found to be the causative agent in our case.

  5. Influence of pesticides on male fertility.

    NARCIS (Netherlands)

    Bretveld, R.W.; Brouwers, M.; Ebisch, I.M.W.; Roeleveld, N.

    2007-01-01

    Several studies have shown a decline in human semen quality and increased risks of male subfertility. This paper provides an overview of the mechanisms of pesticide-induced reproductive toxicity and the effects on male fertility since exposure to pesticides may be one of the causes of these

  6. Earthworm tolerance to residual agricultural pesticide contamination

    DEFF Research Database (Denmark)

    Givaudan, Nicolas; Binet, Françoise; Le Bot, Barbara

    2014-01-01

    conventional cultivation to organic pasture. Soil multiresidual pesticide analysis revealed up to 9 molecules including atrazine up to 2.4 ng g -1 dry soil. Exposure history of endogeic Aporrectodea caliginosa and Allolobophora chlorotica modified their responses to pesticides. In the field, activities...

  7. Pesticide biotransformation and fate in heterogeneous environments

    NARCIS (Netherlands)

    Vink, J.P.M.

    1997-01-01

    The effects and relative impacts of environmental variables on the behaviour of pesticides, through the effect on pesticide-degrading microorganisms, was studied in a broad spectrum and covered the most relevant emission routes. It is shown that the effect of landscape geochemistry, which

  8. [Evidence of pesticide exposure by hair analysis].

    Science.gov (United States)

    Cirimele, V; Kintz, P; Ludes, B

    1999-01-01

    The current report summarizes the development of an analytical method for the identification and the quantification of pesticides in hair by gas chromatography/mass spectrometry and its application to 75 real samples. Hair strands [table: see text] were obtained from wine workers exposed to one or more pesticides. After decontamination, hair were cut into small pieces and incubated overnight at 45 degrees C in methanol. The solvent was evaporated to dryness, the dry extract was redissolved in methanol and injected in a gas chromatography/mass spectrometry system. The detector was operated in electronic impact and in negative chemical ionization mode of detection (reactant gas: methane). In the first series of 75 hair specimens, obtained before the period of pesticide use, none of the 15 target compounds was detected. In the second series of 75 specimens, obtained from the same subjects but after the use of pesticides, 14 tested positive for 9 different pesticides.

  9. Trends and Challenges in Pesticide Resistance Detection.

    Science.gov (United States)

    2016-10-01

    Pesticide resistance is a crucial factor to be considered when developing strategies for the minimal use of pesticides while maintaining pesticide efficacy. This goal requires monitoring the emergence and development of resistance to pesticides in crop pests. To this end, various methods for resistance diagnosis have been developed for different groups of pests. This review provides an overview of biological, biochemical, and molecular methods that are currently used to detect and quantify pesticide resistance. The agronomic, technical, and economic advantages and drawbacks of each method are considered. Emerging technologies are also described, with their associated challenges and their potential for the detection of resistance mechanisms likely to be selected by current and future plant protection methods.

  10. Agricultural pesticides and precocious puberty.

    Science.gov (United States)

    Ozen, Samim; Goksen, Damla; Darcan, Sukran

    2014-01-01

    The onset and course of puberty is under the control of the neuroendocrine system. Factors affecting the regulation of timing and order of this system's functions may alter the onset and course of puberty. Several environmental endocrine disruptors (EDs) with significant influences on the normal course of puberty have been identified. Despite the numerous animal and human studies on EDs that may extensively affect human health, there are still several issues that need to be clarified. This chapter discusses the effects of pesticides, which constitute a significant portion of disruptors and have been increasingly used in agriculture, on precocious puberty.

  11. Intracellular NHX-Type Cation/H+ Antiporters inPlants

    Institute of Scientific and Technical Information of China (English)

    2014-01-01

    Cells depend on the homeostatic maintenance of pHwithin specific cellular compartments to ensure optimalconditions for metabolic and enzymatic processes as wellas protein structure and function. In the animal secre-tory pathway, cells maintain distinct luminal pHs withinvarious compartments (Paroutis et al., 2004). Among themany molecular players that contribute to pH and ionhomeostasis in plants, Na+(K+)/H+ exchangers (also knownas NHX-type cation/H+ antiporters) appear to be particu-larly important for the regulation of a wide variety ofphysiological processes, including cell expansion, cellvolume regulation, osmotic adjustment, pH regulation,membrane trafficking, protein processing, and cellularstress responses (Pardo et al., 2006; Rodriguez-Rosaleset al., 2009; Bassil et al., 2012). In plants, NHX antiportersappeared early in evolution and are ubiquitously encodedmembers of the CPA1 cation/H+ antiporters subgroupthat belongs to the large family of monovalent cation/H+ transporters CPA (Brett et al., 2005). NHX antiport-ers are found, thus far, in all sequenced plant genomes(Bassil et al., 2012; Chanroj et al., 2012). In Arabidopsis,the NHX family consists of eight isoforms, six of whichare intracellular (AtNHXl-AtNHX6), located either to thevacuole (AtNHXl to AtNHX4) or endosomes (AtNHX5 andAtNHX6) and an additional two more divergent members(AtNHX7/SOSl and AtNHX8) at the plasma membrane(Bassil et al., 2012). Orthologous sequences in each of thethree classes (plasma membrane, vacuolar, or endosomal)appear in all sequenced genomes, suggesting that distinctfunctional NHX classes appeared early in evolution andmay have conserved roles that are compartment-specific(Bassil et al., 2012). Emerging new evidence highlightsthe importance of particular intracellular NHX antiport-ers in the regulation of vesicular and vacuolar pH andK+ homeostasis. Vacuolar NHXs are needed to maintainK+ homeostasis

  12. Cationic ruthenium alkylidene catalysts bearing phosphine ligands.

    Science.gov (United States)

    Endo, Koji; Grubbs, Robert H

    2016-02-28

    The discovery of highly active catalysts and the success of ionic liquid immobilized systems have accelerated attention to a new class of cationic metathesis catalysts. We herein report the facile syntheses of cationic ruthenium catalysts bearing bulky phosphine ligands. Simple ligand exchange using silver(i) salts of non-coordinating or weakly coordinating anions provided either PPh3 or chelating Ph2P(CH2)nPPh2 (n = 2 or 3) ligated cationic catalysts. The structures of these newly reported catalysts feature unique geometries caused by ligation of the bulky phosphine ligands. Their activities and selectivities in standard metathesis reactions were also investigated. These cationic ruthenium alkylidene catalysts reported here showed moderate activity and very similar stereoselectivity when compared to the second generation ruthenium dichloride catalyst in ring-closing metathesis, cross metathesis, and ring-opening metathesis polymerization assays.

  13. Cation locations and dislocations in zeolites

    Science.gov (United States)

    Smith, Luis James

    The focus of this dissertation is the extra-framework cation sites in a particular structural family of zeolites, chabazite. Cation sites play a particularly important role in the application of these sieves for ion exchange, gas separation, catalysis, and, when the cation is a proton, acid catalysis. Structural characterization is commonly performed through the use of powder diffraction and Rietveld analysis of powder diffraction data. Use of high-resolution nuclear magnetic resonance, in the study of the local order of the various constituent nuclei of zeolites, complements well the long-range order information produced by diffraction. Recent developments in solid state NMR techniques allow for increased study of disorder in zeolites particularly when such phenomena test the detection limits of diffraction. These two powerful characterization techniques, powder diffraction and NMR, offer many insights into the complex interaction of cations with the zeolite framework. The acids site locations in SSZ-13, a high silica chabazite, and SAPO-34, a silicoaluminophosphate with the chabazite structure, were determined. The structure of SAPO-34 upon selective hydration was also determined. The insensitivity of X-rays to hydrogen was avoided through deuteration of the acid zeolites and neutron powder diffraction methods. Protons at inequivalent positions were found to have different acid strengths in both SSZ-13 and SAPO-34. Other light elements are incorporated into zeolites in the form of extra-framework cations, among these are lithium, sodium, and calcium. Not amenable by X-ray powder diffraction methods, the positions of such light cations in fully ion-exchanged versions of synthetic chabazite were determined through neutron powder diffraction methods. The study of more complex binary cation systems were conducted. Powder diffraction and solid state NMR methods (MAS, MQMAS) were used to examine cation site preferences and dislocations in these mixed-akali chabazites

  14. Pesticide Toxicity Index: a tool for assessing potential toxicity of pesticide mixtures to freshwater aquatic organisms

    Science.gov (United States)

    Nowell, Lisa H.; Norman, Julia E.; Moran, Patrick W.; Martin, Jeffrey D.; Stone, Wesley W.

    2014-01-01

    Pesticide mixtures are common in streams with agricultural or urban influence in the watershed. The Pesticide Toxicity Index (PTI) is a screening tool to assess potential aquatic toxicity of complex pesticide mixtures by combining measures of pesticide exposure and acute toxicity in an additive toxic-unit model. The PTI is determined separately for fish, cladocerans, and benthic invertebrates. This study expands the number of pesticides and degradates included in previous editions of the PTI from 124 to 492 pesticides and degradates, and includes two types of PTI for use in different applications, depending on study objectives. The Median-PTI was calculated from median toxicity values for individual pesticides, so is robust to outliers and is appropriate for comparing relative potential toxicity among samples, sites, or pesticides. The Sensitive-PTI uses the 5th percentile of available toxicity values, so is a more sensitive screening-level indicator of potential toxicity. PTI predictions of toxicity in environmental samples were tested using data aggregated from published field studies that measured pesticide concentrations and toxicity to Ceriodaphnia dubia in ambient stream water. C. dubia survival was reduced to ≤ 50% of controls in 44% of samples with Median-PTI values of 0.1–1, and to 0% in 96% of samples with Median-PTI values > 1. The PTI is a relative, but quantitative, indicator of potential toxicity that can be used to evaluate relationships between pesticide exposure and biological condition.

  15. Microbial pesticides [data requirements for environmental risk assessment

    NARCIS (Netherlands)

    Mensink BJWG; Linders JBHJ; CSR

    1997-01-01

    The market for microbial pesticides is, though slowly, expanding. Therefore more research with these pesticides will be carried out in the near future, not only for agronomical and economical, but also for environmental reasons. As more chemical pesticides are going to be banned, microbial pesticid

  16. 40 CFR 170.130 - Pesticide safety training for workers.

    Science.gov (United States)

    2010-07-01

    ... (iii) Have completed a pesticide safety train-the-trainer program approved by a State, Federal, or... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Pesticide safety training for workers...) PESTICIDE PROGRAMS WORKER PROTECTION STANDARD Standard for Workers § 170.130 Pesticide safety training...

  17. An EPA Modeling Dashboard for Ecological Assessment of Pesticides

    Science.gov (United States)

    The EPA registers pesticides for use in the US and approves imported pesticides under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA). Before a pesticide can be registered, the EPA must assess whether the pesticide can be used without eing harmful to humans or pos...

  18. Apply Pesticides Correctly: A Guide for Commercial Applicators.

    Science.gov (United States)

    Environmental Protection Agency, Washington, DC.

    This document provides practical information needed by commercial pesticide applicators to meet the minimum Federal regulation requirements for the use of various pesticides. The text and accompanying illustrations cover the seven major topics of pests, pest control, pesticides, labels and labeling, using pesticides safely, application equipment,…

  19. Cationized Carbohydrate Gas-Phase Fragmentation Chemistry

    Science.gov (United States)

    Bythell, Benjamin J.; Abutokaikah, Maha T.; Wagoner, Ashley R.; Guan, Shanshan; Rabus, Jordan M.

    2016-11-01

    We investigate the fragmentation chemistry of cationized carbohydrates using a combination of tandem mass spectrometry, regioselective labeling, and computational methods. Our model system is D-lactose. Barriers to the fundamental glyosidic bond cleavage reactions, neutral loss pathways, and structurally informative cross-ring cleavages are investigated. The most energetically favorable conformations of cationized D-lactose were found to be similar. In agreement with the literature, larger group I cations result in structures with increased cation coordination number which require greater collision energy to dissociate. In contrast with earlier proposals, the B n -Y m fragmentation pathways of both protonated and sodium-cationized analytes proceed via protonation of the glycosidic oxygen with concerted glycosidic bond cleavage. Additionally, for the sodiated congeners our calculations support sodiated 1,6-anhydrogalactose B n ion structures, unlike the preceding literature. This affects the subsequent propensity of formation and prediction of B n /Y m branching ratio. The nature of the anomeric center (α/β) affects the relative energies of these processes, but not the overall ranking. Low-energy cross-ring cleavages are observed for the metal-cationized analytes with a retro-aldol mechanism producing the 0,2 A 2 ion from the sodiated forms. Theory and experiment support the importance of consecutive fragmentation processes, particularly for the protonated congeners at higher collision energies.

  20. Cationized Carbohydrate Gas-Phase Fragmentation Chemistry

    Science.gov (United States)

    Bythell, Benjamin J.; Abutokaikah, Maha T.; Wagoner, Ashley R.; Guan, Shanshan; Rabus, Jordan M.

    2017-04-01

    We investigate the fragmentation chemistry of cationized carbohydrates using a combination of tandem mass spectrometry, regioselective labeling, and computational methods. Our model system is D-lactose. Barriers to the fundamental glyosidic bond cleavage reactions, neutral loss pathways, and structurally informative cross-ring cleavages are investigated. The most energetically favorable conformations of cationized D-lactose were found to be similar. In agreement with the literature, larger group I cations result in structures with increased cation coordination number which require greater collision energy to dissociate. In contrast with earlier proposals, the B n -Y m fragmentation pathways of both protonated and sodium-cationized analytes proceed via protonation of the glycosidic oxygen with concerted glycosidic bond cleavage. Additionally, for the sodiated congeners our calculations support sodiated 1,6-anhydrogalactose B n ion structures, unlike the preceding literature. This affects the subsequent propensity of formation and prediction of B n /Y m branching ratio. The nature of the anomeric center (α/β) affects the relative energies of these processes, but not the overall ranking. Low-energy cross-ring cleavages are observed for the metal-cationized analytes with a retro-aldol mechanism producing the 0,2 A 2 ion from the sodiated forms . Theory and experiment support the importance of consecutive fragmentation processes, particularly for the protonated congeners at higher collision energies.

  1. 40 CFR 152.10 - Products that are not pesticides because they are not intended for a pesticidal purpose.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Products that are not pesticides... ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS PESTICIDE REGISTRATION AND CLASSIFICATION PROCEDURES General Provisions § 152.10 Products that are not pesticides because they are not intended for...

  2. Pesticides in Brazilian freshwaters: a critical review.

    Science.gov (United States)

    Albuquerque, A F; Ribeiro, J S; Kummrow, F; Nogueira, A J A; Montagner, C C; Umbuzeiro, G A

    2016-07-13

    The widespread use of pesticides in agriculture can lead to water contamination and cause adverse effects on non-target organisms. Brazil has been the world's top pesticide market consumer since 2008, with 381 approved pesticides for crop use. This study provides a comprehensive literature review on the occurrence of pesticide residues in Brazilian freshwaters. We searched for information in official agency records and peer-reviewed scientific literature. Risk quotients were calculated to assess the potential risk posed to aquatic life by the individual pesticides based on their levels of water contamination. Studies about the occurrence of pesticides in freshwaters in Brazil are scarce and concentrated in few sampling sites in 5 of the 27 states. Herbicides (21) accounted for the majority of the substances investigated, followed by fungicides (11), insecticides (10) and plant growth regulators (1). Insecticides are the class of major concern. Brazil would benefit from the implementation of a nationwide pesticide freshwater monitoring program to support preventive, remediation and enforcement actions.

  3. Low-dose aspirin use does not diminish the immune response to monovalent H1N1 influenza vaccine in older adults.

    Science.gov (United States)

    Jackson, M L; Bellamy, A; Wolff, M; Hill, H; Jackson, L A

    2016-03-01

    Non-steroidal anti-inflammatory drugs (NSAIDs) may inhibit antibody production by peripheral blood mononuclear cells; one consequence of this could be decreased effectiveness of vaccines in NSAID users. Because many older adults use low-dose aspirin for primary or secondary prevention of coronary events, any inhibitory effect of aspirin on vaccine immune response could reduce the benefits of vaccination programmes in older adults. We tested whether immune response to vaccination differed between users vs. non-users of low-dose aspirin, using data from four randomized trials of monovalent 2009 pandemic influenza A(H1N1) vaccine. Geometric mean haemagglutination inhibition antibody titres were not significantly lower in low-dose aspirin users compared to non-users. Our results provide reassurance that influenza vaccination effectiveness is probably not reduced in older adults taking chronic low-dose aspirin.

  4. The effect of primycin on the intracellular monovalent ion and water contents of rat hepatocytes as revealed by energy dispersive X-ray microanalysis and interference microscopy.

    Science.gov (United States)

    Horváth, I; Nagy, I; Lustyik, G; Váradi, G

    1983-01-01

    Using energy-dispersive X-ray microanalytic and interference microscopic techniques, the intracellular concentration of the monovalent ions (Na+, K+, Cl+) as well as the intracytoplasmic and intracellular water contents were studied in normal and adrenalectomized rat hepatocytes with and without primycin treatment. Although primycin influenced significantly only the intracellular potassium content of the adrenalectomized group, it exerted a marked influence on the intranuclear water content in both the normal and adrenalectomized rats. The intranuclear water content increased significantly in the primycin-treated animals. The conclusion is drawn that the increased level of hydration of the nuclear substances reflects a 'decondensation' of the chromatin which on the other hand, may represent the basis for the various effects of primycin on the induction of certain hepatic enzymes.

  5. Long-term lessons on pesticide leaching obtained via the Danish Pesticide Leaching Assessment Programme

    DEFF Research Database (Denmark)

    Rosenbom, Anette E.; Olsen, Preben; Plauborg, Finn

    To avoid any unacceptable influence on the environment posed by pesticides and their degradation products, all pesticides used in the European Union needs authorization. The authorization procedure includes assessing the leaching risk of both pesticides and their degradation products...... to the groundwater. There are shortcomings to the procedure, however, as revealed by the results of the Danish Pesticide Leaching Assessment Programme from the period 1990/2000 to 2012 (app. twelve years). This monitoring program has for this period assessed leaching into groundwater via the variably-saturated zone...... of 43 pesticides applied in accordance with current regulations on sandy and loamy agricultural fields, and 47 of their degradation products. Three types of leaching scenario were not fully captured by the authorization procedure: i) long-term leaching of degradation products of pesticides applied...

  6. The effect of crop rotation on pesticide leaching in a regional pesticide risk assessment.

    Science.gov (United States)

    Balderacchi, Matteo; Di Guardo, Andrea; Vischetti, Costantino; Trevisan, Marco

    2008-11-01

    New modeling approaches that include the use of GIS are under development in order to allow a more realistic assessment of environmental contamination by pesticides. This paper reports a regional GIS-based risk assessment using a software tool able to simulate complex and real crop rotations at the regional scale. A single pesticide leaching assessment has been done. The mean annual pesticide concentration in leachate has been analyzed using both stochastic and deterministic approaches. The outputs of these simulations were mapped over the sampling locations of the regional pesticide monitoring program, demonstrating that GIS-based risk assessment can be used to establish new monitoring programs. A multiple pesticide leaching assessment for analyzing the risk related to pest control strategies in six different maize-based rotations has been carried out. Additive toxic units approach has been used. Crop rotation allows to mediate the risk related to pesticide use because forces the use of different compounds with different fate and toxicology properties.

  7. Electrical transport and EPR investigations: A comparative study for d.c. conduction mechanism in monovalent and multivalent ions doped polyaniline

    Indian Academy of Sciences (India)

    Suresh Kumar Gupta; Vandna Luthra; Ramadhar Singh

    2012-10-01

    A detailed comparative study of electron paramagnetic resonance (EPR) in conjunction with d.c. electrical conductivity has been undertaken to know about the charge transport mechanism in polyaniline (PANI) doped with monovalent and multivalent protonic acids. This work is in continuation of our previous work for further understanding the conduction mechanism in conducting polymers. The results reveal that the polarons and bipolarons are the main charge carriers formed during doping process and these cause increase in electrical conductivity not only by increase in their concentration but also because of their enhanced mobility due to increased inter-chain transport in polyaniline at high doping levels. EPR line asymmetry having Dysonian line shape for highly doped samples shows a marked deviation of amplitudes / ratio from values close to one to much high values as usually observed in metals, thereby support the idea of high conductivity at higher doping levels. The nature of dopant ions and their doping levels control the charge carriers concentration as well as electrical conductivity of polyaniline. The electrical conductivity has also been studied as a function of temperature to know the thermally assisted transport process of these charge carriers at different doping levels which has been found to follow the Mott’s variable range hopping (VRH) conduction model for all the three dopants used. The charge carriers show a change over from 3D VRH to quasi 1D VRH hopping process for multivalent ions at higher doping levels whereas 1D VRH has been followed by monovalent ion for full doping range. These studies collectively give evidence of inter-chain percolation at higher doping levels causing increase in effective mobility of the charge carriers which mainly seems to govern the electrical conduction behaviour in this system.

  8. Pesticide leaching in a changing climate

    DEFF Research Database (Denmark)

    Rasmussen, Signe Bonde

    leaching amounts under specific pre and post event weather conditions. This clearly illustrated the importance of including weather variability in pesticide fate modelling. An ensemble of 11 climate model projections were downscaled by perturbing a weather generator calibrated on local meteorological data......, resulting in 3000-year long weather series of statistically stationary climate. Effects of pesticide properties (sorption and degradation), pesticide application dates, and soil properties were included. The synthetic weather series produced in relation to objective (II) were used to simulate future changes...

  9. [Effects of organochloride pesticides on dyslipidemias].

    Science.gov (United States)

    Shao, W T; Gu, A H

    2016-11-06

    Dyslipidemias is one important risk factor associated with chronic diseases. Persistent organic pollutants are resistant to degradation and can be bio-accumulated and magnified through the food chain. Recently, the relation between dyslipidemias and organochlorine pesticides has attracted more attentions. In this review, we explored the distribution of organochloride pesticides in the environment and human body, as well as the possible underlying mechanisms of the association between dyslipidemias and organochloride pesticides, including accumulation and release of organochloride, simulation of estrogen, impact on PPARs, the metabolic fingerprint, and the inflammatory reaction.

  10. Contamination of the freshwater ecosystem by pesticides

    Science.gov (United States)

    Cope, Oliver B.

    1966-01-01

    A large part of our disquieting present-day pesticide problem is intimately tied to the freshwater ecosystem. Economic poisons are used in so many types of terrain to control so many kinds of organisms that almost all lakes and streams are likely to be contaminated. In addition to accidental contamination many pesticides are deliberately applied directly to fresh waters for suppression of aquatic animals or plants. The problem is intensified because of the extreme susceptibility of freshwater organisms. The complexity of freshwater environments and their variety makes it difficult to comprehend the total effect of pesticides.

  11. Chiral pesticides: Identification, description, and environmental implications

    Science.gov (United States)

    Ulrich, Elin M.; Morrison, Candice N.; Goldsmith, Michael R.; Foreman, William T.

    2012-01-01

    Anthropogenic chemicals, including pesticides, are a major source of contamination and pollution in the environment. Pesticides have many positive uses: increased food production, decreased damage to crops and structures, reduced disease vector populations, and more. Nevertheless, pesticide exposure can pose risks to humans and the environment, so various mitigation strategies are exercised to make them safer, minimize their use, and reduce their unintended environment effects. One strategy that may help achieve these goals relies on the unique properties of chirality or molecular asymmetry. Some common terms related to chirality are defined in Table 1.

  12. Status of pesticides pollution in Tanzania - A review.

    Science.gov (United States)

    Elibariki, Raheli; Maguta, Mihayo Musabila

    2017-07-01

    Various studies have been conducted in Tanzania to assess the magnitude of pesticides pollution associated with pesticides application, storage, disposal as well as knowledge of farmers on pesticides handling. The studies analysed samples from different matrices covering vegetation, biota, water, sediments and soil. The objective of this review was to summarise the results of pesticides residues reported in different components of the environment to give a clear picture of pesticides pollution status in the country for law enforcement as well as for taking precaution measures. Gaps which need to be filled in order to establish a comprehensive understanding on pesticides pollution in the country have also been highlighted. Reviewed studies revealed that, most of the samples contained pesticides below permissible limits (WHO, FAO, US-EPA) except for few samples such as water from Kikavu river, Kilimanjaro region and Kilolo district, Iringa region which were detected with some Organochlorine pesticides (OCPs) above WHO permissible limits. Some soil samples from the former storage sites also contained pesticides above FAO permissible limits. Pesticides and their metabolites were also detected both in vegetation, food and biota samples. The prevalent pesticides in the reviewed studies were the organochlorines such as Dichlorodiphenyltrichloroethane (DDT), endosulfan and Hexachlorocyclohexane (HCH). Surveys to assess farmer's knowledge on pesticides handling observed poor understanding of farmers on pesticides storage, application and disposal. Decontamination of former storage areas, continuous monitoring of pesticide applications and training of farmers on proper handling of pesticides are highly recommended. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Interactions between amino-phosphonates pesticides and titanium dioxide nanoparticle in water: consequences on their mobility

    Science.gov (United States)

    Ilina, Svetlana; Baran, Nicole; Slomberg, Danielle; Devau, Nicolas; Pariat, Anne; Sani-Kast, Nicole; Scheringer, Martin; Labille, Jérôme; Ollivier, patrick

    2017-04-01

    Water quality is increasingly monitored worldwide, where various levels of nitrate and pesticide and/or metabolite contamination have been confirmed. Glyphosate [N-(phosphonomethyl)glycine] is probably the most widely used herbicide in the world. AMPA [aminomethylphosphonic acid] is its main degradation product. Although glyphosate mobility in the environment is supposed to be limited because of its high adsorption capacity in soils several studies show that glyphosate may reach both surface and ground-waters either by transport in dissolved form, or particle bonded onto soil colloids. At the same time, in recent years, rapid development of new technologies has resulted in a significant increase in the production and uses of products containing nanoparticles, notably dioxide titanium nanoparticles. This enthusiasm for nanotechnology is however accompanied by awareness about the potential release and impact of the nanoparticles in the environment. The aim of the study is to increase the knowledge on pesticide and nanoparticles interactions that may be present as contaminant cocktail in waters. Thanks to lab-experiments conducted with glyphosate or AMPA and rutile or anatase under different water chemistry conditions (pH, ionic strength, presence and concentrations of mono- and bivalent cations), we were able to describe the colloidal stability of nanoparticles that control their mobility and to characterize the sorption of pesticide on these nanoparticles and their transformation.

  14. Pesticides

    Science.gov (United States)

    ... Home Page Brochures & Fact Sheets Environmental Health Topics Science Education Kids Environment | Kids Health Research Home Page At NIEHS ... Agents Water Pollution Environmental Science Basics Population Research Science Education Kids Environment | Kids Health Research Home Research At NIEHS ...

  15. The effect of monovalent and divalent cations on the ATP-dependent Ca2+-binding and phosphorylation during the reaction cycle of the sarcoplasmic reticulum Ca2+-transport ATPase.

    Science.gov (United States)

    Medda, P; Fassold, E; Hasselbach, W

    1987-06-01

    The coupling of Ca2+ movements and phosphate fluxes as well as the time-dependent occurrence of sequential reaction intermediates in the forward mode of the Ca,Mg-dependent ATPase reaction have been investigated using leaky vesicles (A23187) in the presence of varying Ca2+, Mg2+, and K+ concentrations. The employed ATP concentration of 2 microM does not allow more than one reaction cycle to occur. The respective fractions of ADP-sensitive and ADP-insensitive phosphoenzyme have been determined. The chosen experimental conditions (0-1 degree C, pH 6.0, absence of solubilizers) allow a prolonged time of observation and exclude interfering alterations of coupling and binding parameters, respectively. It is shown that under the experimental conditions K+ interacts with at least four different reaction steps (phosphoenzyme formation, E1P----E2P transition, E2P hydrolysis, and E2----E1 transformation). Mg2+ represents the sole ionic co-factor for the formation of the substrate MgATP if it is present in high concentrations (5 mM). Additional Ca2+ is bound to the substrate as well as to unspecific sites otherwise occupied by Mg2+ if Mg2+ is reduced to 0.1 mM. In this case the E1P----E2P transition rate (including Ca2+ translocation and Ca2+ release from low-affinity sites) is little diminished. If, in the absence of K+, both Mg2+ and Ca2+ are deficient E2P hydrolysis is vastly retarded. We find Ca2+ release to occur time-coincidently with E1P formation and not concomitantly with the comparably slow appearance of E2P; the molar amount of Ca2+ released, however, rather agreed with that of E2P formed. This suggests that under the prevailing conditions of a high proton concentration, phosphoenzyme states containing occluded Ca2+ or Ca2+ bound to low-affinity sites are transitional and not detectable. Preliminary findings on this subject have been published by us and colleagues from this laboratory [Hasselbach, W., Agostini, B., Medda, P., Migala, A. & Waas, W. (1985) in The sarcoplasmic reticulum calcium pump: Early and recent developments critically overviewed (Fleischer, S. & Tonomura, Y., eds) pp. 19-49, Academic Press, Orlando].

  16. The effect of cations on the aggregation of commercial ZnO nanoparticle suspension

    Science.gov (United States)

    Liu, Wei-Szu; Peng, Yu-Huei; Shiung, Chia-En; Shih, Yang-hsin

    2012-12-01

    Nanoscale ZnO materials have been largely used in many products due to their distinct properties. However, ZnO nanoparticles (NPs) are hazardous to human health and the ecosystem. The characteristics and the stability of ZnO NPs are relevant to their fate in the environment and their potential toxicities. In this study, a stable commercial ZnO NP suspension was chosen to investigate its aggregation under various salt additions. Different concentrations of NaCl, KCl and CaCl2 were chosen to represent various environmental conditions. Under pH 8-9, the surface charge of commercial ZnO NPs was negative. The behavior of the stabilized ZnO NPs in water was affected by ionic combinations and ionic strength; that is, divalent cations were more effective than monovalent ones in promoting aggregation formation. The attachment efficiencies of ZnO aggregates were calculated based upon the aggregation kinetics. The critical coagulation concentration values for this commercial ZnO NPs were higher than previous reported for ZnO NPs, indicating this ZnO NP could be stable in the aquatic environment and might have increased hazardous potentials. Based upon the Derjaguin-Landau-Verwey-Overbeek theory, interactions between ZnO NPs in the presence of different ions were evaluated to illustrate the aggregation mechanism. Our results indicated that critical ionic type and concentration promote the aggregation of stable ZnO NPs. These understandings also can facilitate the design of the precipitation treatment to remove NPs from water.

  17. Neonatal outcome following exposure to organophosphorous pesticides

    Directory of Open Access Journals (Sweden)

    Đorđević M.

    2010-01-01

    Full Text Available The aim of our study was to determine the neonatal outcome in mothers and children exposed to organophosphorous pesticides (OP. We found that 22.4% pregnant women were exposed to organophosphorous pesticides. OP pesticide concentration was higher in breast milk, newborn sera than maternal sera. Newborn parameters such as birth weight, birth length, head circumference, Apgar score and presence of meconium, as well as gestational age of delivery, showed no significant difference between the two groups. However, postpartum weight loss, hospitalization duration, levels of newborn bilirubin and glycaemia differed significantly between the two groups. Morbidity and presence of CNS disorders were six times and more than twelve times higher, respectively, in the OP-exposed than in the OP pesticide non-exposed group.

  18. CONTAMINANTS AND REMEDIAL OPTIONS AT PESTICIDE SITES

    Science.gov (United States)

    Many types of soils, sediments, and sludges are contaminated with a wide variety of pesticides. ite-specific characteristics such as volume to be treated, extent of contamination, and applicable cleanup goals differ greatly, and contaminant toxicity, migration pathways, persisten...

  19. High risk pesticides in sugar beet protection

    Directory of Open Access Journals (Sweden)

    Šovljanski Radmila A.

    2006-01-01

    Full Text Available According to traits of pesticides permitted to use in sugar beet (oral percutaneus and inhalation toxicity, toxicity to wildlife, bees and aquatic organisms, re-entry interval, maximum number of treatments, effects on reproduction do not present health risk in sugar production/technology. However, the danger exists for workers by chronic exposure during the application, especially from pesticide being potential endocrine disruptors (EDS (fentin acetate, benomyl, endosulfan, methomyl, methidathion. EDS can cause sterility or decreased fertility, impaired development, birth defects of the reproductive tract and metabolic disorders. Authors recommend limited application of EDS pesticides (to limit the number of treatments to only one during the vegetation, replacement with pesticides with low risk to humans game and fishes, as well as mandatory submission of re-entry data for registration.

  20. Jiangsu Pesticide Research Institute Company Ltd.

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    @@ Jiangsu Pesticide Research Institute Company Ltd. was established on June 22, 2005, with the registered capital of RMB 40.4 million. Its business includes R&D, manufacture and market of agrochemicals.

  1. Interim Policy for Evaluation of Stereoisomeric Pesticides

    Science.gov (United States)

    An interim approach for determining data requirements for non-racemic mixtures of stereoisomeric pesticides. These data are needed in order to assess the risk posed to ecosystems and drinking water sources by these mixtures.

  2. 75 FR 26754 - Pesticide Products; Registration Applications

    Science.gov (United States)

    2010-05-12

    ... Products; Registration Applications AGENCY: Environmental Protection Agency (EPA). ACTION: Notice. SUMMARY: EPA has received applications to register pesticide products containing active ingredients not... receipt and opportunity to comment on these applications. DATES: Comments must be received on or before...

  3. 77 FR 18710 - Acetamiprid; Pesticide Tolerances

    Science.gov (United States)

    2012-03-28

    ... member of the neonicotinoid class of pesticides which also includes thiamethoxam, clothianidin... preliminary evidence suggests that clothianidin operates by direct competitive inhibition, while thiamethoxam...., testicular tubular atrophy with thiamethoxam; mineralized particles in thyroid colloid with...

  4. Pesticides in Wyoming Groundwater, 2008-10

    Science.gov (United States)

    Eddy-Miller, Cheryl A.; Bartos, Timothy T.; Taylor, Michelle L.

    2013-01-01

    Groundwater samples were collected from 296 wells during 1995-2006 as part of a baseline study of pesticides in Wyoming groundwater. In 2009, a previous report summarized the results of the baseline sampling and the statistical evaluation of the occurrence of pesticides in relation to selected natural and anthropogenic (human-related) characteristics. During 2008-10, the U.S. Geological Survey, in cooperation with the Wyoming Department of Agriculture, resampled a subset (52) of the 296 wells sampled during 1995-2006 baseline study in order to compare detected compounds and respective concentrations between the two sampling periods and to evaluate the detections of new compounds. The 52 wells were distributed similarly to sites used in the 1995-2006 baseline study with respect to geographic area and land use within the geographic area of interest. Because of the use of different types of reporting levels and variability in reporting-level values during both the 1995-2006 baseline study and the 2008-10 resampling study, analytical results received from the laboratory were recensored. Two levels of recensoring were used to compare pesticides—a compound-specific assessment level (CSAL) that differed by compound and a common assessment level (CAL) of 0.07 microgram per liter. The recensoring techniques and values used for both studies, with the exception of the pesticide 2,4-D methyl ester, were the same. Twenty-eight different pesticides were detected in samples from the 52 wells during the 2008-10 resampling study. Pesticide concentrations were compared with several U.S. Environmental Protection Agency drinking-water standards or health advisories for finished (treated) water established under the Safe Drinking Water Act. All detected pesticides were measured at concentrations smaller than U.S. Environmental Protection Agency drinking-water standards or health advisories where applicable (many pesticides did not have standards or advisories). One or more pesticides

  5. How Stereochemistry Considerations can Improve Pesticide Safety

    Science.gov (United States)

    About 30% of pesticides are chiral molecules and therefore exist as two or more stereoisomers, which can differ significantly in their toxicity, biodegradation, and persistence. Such differences can impact their relative safety to humans and environmental species. Enantiomers, mi...

  6. Improved indicators and monitoring of pesticide use

    DEFF Research Database (Denmark)

    Sørensen, Peter Borgen; Kjær, Christian; Kudsk, Per

      The goal for the new improved indicator, PestNaB (Pesticiders NaturBelastning), was to develop a valid indicator reflecting the potential risk for nature due to application of pesticides and based on available data set for Danish conditions. The focus is on risk in relation the nature close to...... separately: (1) Terrestrial nature; (2) Steams; (3) Ponds and lakes. GIS is used to combine data for agriculture praxis in terms of the crop distribution with distance to the nature elements. Pesticide application was estimated based on crop distribution and the toxicity for a series of toxic end......-points covering Fish, daphnia, mammals, arthropods, insects, algae and plants. Totally 18 separated indicators are calculated for each km2 in Denmark and feed into a multi criterion analysis using a partial order method. Like all others pesticide indicators this indicator is relative. So, it is possible...

  7. Organophosphorus pesticide poisoning : cases and developments

    NARCIS (Netherlands)

    Aardema, H.; Ligtenberg, J. J. M.; Peters-Polman, O. M.; Tulleken, J. E.; Zijlstra, J. G.; Meertens, John H. J. M.

    2008-01-01

    Self-poisoning with organophosphate pesticides is a major health problem world-wide. Through the inhibition of acetylcholinesterase, organophosphorus poisoning is characterised by the clinical picture of acute cholinergic crisis. Other manifestations are the intermediate neurotoxic syndrome and dela

  8. Assessing Pesticides under the Endangered Species Act

    Science.gov (United States)

    EPA’s pesticide risk assessment and regulatory processes ensure that protections are in place for all populations of non-target species. We have developed risk assessment procedures to determine potential for harm to individuals of a listed species.

  9. Find a Bed Bug Pesticide Product

    Science.gov (United States)

    Introduces the Bed Bug Product Search Tool, to help consumers find EPA-registered pesticides for bed bug infestation control. Inclusion in this database is not an endorsement. Always follow label directions carefully.

  10. 76 FR 61587 - Prothioconazole; Pesticide Tolerances

    Science.gov (United States)

    2011-10-05

    ...), announcing the filing of pesticide petitions (PPs 0F7714 and 0F7715) by Bayer CropScience, P.O. Box 12014, 2... maximum residues. Results from ruminant feeding studies and poultry metabolism studies were used to...

  11. Earthworm tolerance to residual agricultural pesticide contamination

    DEFF Research Database (Denmark)

    Givaudan, Nicolas; Binet, Françoise; Le Bot, Barbara

    2014-01-01

    This study investigates if acclimatization to residual pesticide contamination in agricultural soils is reflected in detoxification, antioxidant enzyme activities and energy budget of earthworms. Five fields within a joint agricultural area exhibited different chemical and farming histories from ...

  12. Chlorinated pesticide residues in marine sediments

    Digital Repository Service at National Institute of Oceanography (India)

    Sarkar, A.; SenGupta, R.

    A number of organochlorine pesticides residues, aldrine, gamma BHC, dieldrine, and DDT were detected and quantified from the marine sediments collected along the east coast of India by gas chromatography using an electron capture detector. Almost...

  13. Endocrine disrupting pesticides: implications for risk assessment.

    Science.gov (United States)

    McKinlay, R; Plant, J A; Bell, J N B; Voulvoulis, N

    2008-02-01

    Endocrine disrupting (ED) chemicals are compounds that alter the normal functioning of the endocrine system, potentially causing disease or deformity in organisms and their offspring. Pesticides are used widely to kill unwanted organisms in crops, public areas, homes and gardens and medicinally to kill parasites. Many are proven or suspected to be EDs. Ancient physiological similarities between different vertebrate groups suggest that disorders observed in wildlife may indicate risks to humans. This makes accurate risk assessment and effective legislation difficult. In this paper, the hazardous properties of pesticides which are known to have ED properties are reviewed in order to assess the implications for risk assessment. As well as data on sources of exposure in the United Kingdom (UK) an assessment of the evidence on the health effects of ED pesticides is also included. In total, 127 have been identified from the literature and their effects and modes of action are listed in this paper. Using the UK as a case study, the types and quantities of pesticides used, and their methods of application are assessed, along with their potential pathways to humans. In the UK reliable data are available only for agricultural use, so non-agricultural routes of pesticide exposure have been poorly quantified. The exposure of people resident in or visiting rural areas could also have been grossly under-estimated. Material links between ED pesticide use and specific illnesses or deformities are complicated by the multifactorial nature of disease, which can be affected by factors such as diet. Despite these difficulties, a large body of evidence has accumulated linking specific conditions to ED pesticides in wildlife and humans. A more precautionary approach to the use of ED pesticides, especially for non-essential purposes is proposed.

  14. Bacillus thuringiensis and Its Pesticidal Crystal Proteins

    OpenAIRE

    Schnepf, E.; Crickmore, N; Van Rie, J.; Lereclus, D.; Baum, J; Feitelson, J.; Zeigler, D. R.; Dean, D H

    1998-01-01

    During the past decade the pesticidal bacterium Bacillus thuringiensis has been the subject of intensive research. These efforts have yielded considerable data about the complex relationships between the structure, mechanism of action, and genetics of the organism’s pesticidal crystal proteins, and a coherent picture of these relationships is beginning to emerge. Other studies have focused on the ecological role of the B. thuringiensis crystal proteins, their performance in agricultural and o...

  15. Morbidity in newborns exposed to organophosphorus pesticides

    Directory of Open Access Journals (Sweden)

    Đorđević Momčilo

    2010-01-01

    Full Text Available Introduction. Insecticides are toxines by which we destroy harmful insects. The most frequent insecticides which are used today are organophosphorus pesticides. This group of compounds make substances whose activity mechanism is based on the inhibition of acetylcho­linesterase in nerve synapsis, thus producing holynergic syndrome, resulting from the accumulation of acetylcholine which developed due to the absence of decomposition under the influence of cholinesterase. In the clinical picture of acute toxication by cholinesterase inhibitors there is a clear difference between muscarinic and nicotine effects. The basic aim of the study was to establish the effects of organophosphorus pesticides present in blood and breast milk of mothers on newborns morbidity. Material and methods. The study group consisted of 18 newborns whose mothers had isolated organophosphorus pesticides in their blood and breast­milk on the third day after delivery, and the control group consisted of 84 newborns whose mothers did not have isolated organophosphorus pesticides in their blood and breastmilk. Results. Morbidity is three times greater, often in combination with some disorders of the central nervous system, and the relative risk for its appearance is eight time greater in newborns exposed to organophosphorus pesticides. Disscusion. Disorders that appear in newborns exposed to pesticides are mutagenic, cancerogenic and neurotoxic and some agenses could disturb the immune system which is reflected in morbidity increase, primarly of the central nervous system. Conclusion. The presence of organophosphorus pesticides in blood and breast milk has negative effects on newborns. In addition to acetylcho­linesterase inhibition, organophosphorus pesticides react by means of other mechanisms as well.

  16. Pesticide pollution status in cocoa plantation soil

    Directory of Open Access Journals (Sweden)

    E. Atuanya

    2017-09-01

    Full Text Available Management of cocoa plantation field relied on the use of pesticides over the years; hence, the fate of such chemicals is one of the most debated issues among the stakeholders. Young and old cocoa plantation fields from 4 major cocoa producing States in Nigeria were selected as the study area. Eight composites soil samples collected from 3 portions of 6 transect measured area (100 x 50m of the field were transported to the laboratory in sterile glass jar for analysis. A total of 19 organochlorine pesticides residues; (aldrin, α-hexachlorohexane, β-hexachlorohexane, γ-hexachlorohexane, δ-hexachlorohexane, α-chlordane, γ-chlordane, p,p’-dichlorodiphenyldichloroethane, p,p’-dichlorodiphenyldichloroethylene, p,p’-dichlorodiphenyltrichloroethane, dieldrin, endosulfan I, endosulfan-II, endosulfan sulfate, endrin, endrin aldehydes, heptachlor, heptachlor epoxide and metoxychlor were analyzed with gas chromatography equipped with electron capture detector. The results revealed the variation in the number of residues detected among the study fields. Endosulfan-I had the highest value g organochlorine pesticides residue detected. Most of the residue concentrations were within the European Union regulatory standard of Czech Republic. Other-cyclodine group had the highest concentration value among the evaluated organochlorine pesticides groups. The significant (P < 0.05 higher concentration of total organochlorine pesticides were observed in old fields. Composition quotients values indicate that most of the observed organochlorine pesticides residues were products of historical usage. There were strong correlations among the total organic carbon contents of soils and the total organochlorine pesticides compounds. Government regulatory agencies are encouraged to vigorously embark in further monitoring and ensuring the safety compliance of farmers towards the use of pesticides in Nigeria farms.

  17. Farmers’ Exposure to Pesticides: Toxicity Types and Ways of Prevention

    Directory of Open Access Journals (Sweden)

    Christos A. Damalas

    2016-01-01

    Full Text Available Synthetic pesticides are extensively used in agriculture to control harmful pests and prevent crop yield losses or product damage. Because of high biological activity and, in certain cases, long persistence in the environment, pesticides may cause undesirable effects to human health and to the environment. Farmers are routinely exposed to high levels of pesticides, usually much greater than those of consumers. Farmers’ exposure mainly occurs during the preparation and application of the pesticide spray solutions and during the cleaning-up of spraying equipment. Farmers who mix, load, and spray pesticides can be exposed to these chemicals due to spills and splashes, direct spray contact as a result of faulty or missing protective equipment, or even drift. However, farmers can be also exposed to pesticides even when performing activities not directly related to pesticide use. Farmers who perform manual labor in areas treated with pesticides can face major exposure from direct spray, drift from neighboring fields, or by contact with pesticide residues on the crop or soil. This kind of exposure is often underestimated. The dermal and inhalation routes of entry are typically the most common routes of farmers’ exposure to pesticides. Dermal exposure during usual pesticide handling takes place in body areas that remain uncovered by protective clothing, such as the face and the hands. Farmers’ exposure to pesticides can be reduced through less use of pesticides and through the correct use of the appropriate type of personal protective equipment in all stages of pesticide handling.

  18. Estimation of pyrethroid pesticide intake using regression ...

    Science.gov (United States)

    Population-based estimates of pesticide intake are needed to characterize exposure for particular demographic groups based on their dietary behaviors. Regression modeling performed on measurements of selected pesticides in composited duplicate diet samples allowed (1) estimation of pesticide intakes for a defined demographic community, and (2) comparison of dietary pesticide intakes between the composite and individual samples. Extant databases were useful for assigning individual samples to composites, but they could not provide the breadth of information needed to facilitate measurable levels in every composite. Composite sample measurements were found to be good predictors of pyrethroid pesticide levels in their individual sample constituents where sufficient measurements are available above the method detection limit. Statistical inference shows little evidence of differences between individual and composite measurements and suggests that regression modeling of food groups based on composite dietary samples may provide an effective tool for estimating dietary pesticide intake for a defined population. The research presented in the journal article will improve community's ability to determine exposures through the dietary route with a less burdensome and costly method.

  19. Understanding Pesticide Behaviour At The Catchment Scale

    Science.gov (United States)

    Kannan, N.; White, S. M.; Worrall, F.; Pendlington, D.; Groves, S.

    Pesticides in stream flow at the outlet of a 142ha catchment in Eastern England (Col- worth, Bedfordshire), have been monitored since October 1999. About 50% of the total catchment is directly controlled within one farm and a rotation of wheat, oil seed rape, grass, linseed, beans and peas is grown. The data from this catchment are being used to investigate the performance of the USDA SWAT contaminant transport pack- age at the catchment scale. Three years of stream flow and climate data are available with a useful set of pesticide application and detection data. Following calibration and validation of the hydrology of the catchment, pesticide modelling was carried out for tebuconazole, terbutryn, and terbuthylazine. This paper reports on the results of a sen- sitivity analysis of the model, and the final calibrated pesticide component. Analysis of the results obtained show that the timing and decay of predicted pesticide concen- trations are correct. It is therefore recommended that SWAT can be used as a tool to understand pesticide behaviour at the catchment scale.

  20. Codex alimentarius approach to pesticide residue standards.

    Science.gov (United States)

    Maybury, R B

    1989-01-01

    To protect consumers' health, most countries have maximum legal limits for pesticide residues in foods. Trade difficulties can arise when limits differ between countries. The Codex Alimentarius Commission was established in 1962 to implement the Joint FAO/WHO Food Standards Programme, the purpose of which is to protect consumer health and ensure fair practices in international food trade. The Codex Committee on Pesticide Residues (CCPR), an intergovernmental body which advises the Commission on matters related to pesticide residues, is responsible for establishing maximum residue limits (MRLs) for pesticides in foods and feeds that move in international trade. Codex MRLs are based on residue data obtained mainly from supervised trials that reflect approved pesticide use in accordance with "good agricultural practice." MRLs must be toxicologically acceptable in terms of estimated pesticide intake by consumers. CCPR Working Groups examine problems related to establishing and implementing MRLs, including sampling and methods of analysis. Despite time and effort expended, acceptance and application of Codex MRLs face many problems in international trade.

  1. Pesticides in Soil: Effects on Microorganisms

    Directory of Open Access Journals (Sweden)

    Ljiljana Radivojević

    2007-01-01

    Full Text Available Since their discovery to the present day, pesticides have been an inevitable segment of agricultural production and efforts have been made to synthesize compounds that would share a required efficacy along with selectivity, sufficient persistence on the object of protection and favourable toxicological and ecotoxicological characteristics so as to minimize their effect on the environment.When a pesticide gets into soil after application, it takes part in a number of physical, chemical and biological processes that depend not only on the compound itself, but a number of other factors as well, such as: physical, chemical and biological characteristics of soil; climatic factors, equipment used, method of application, method of storage, handling and disposal of waste, site characteristics (proximity of ground and underground waters, biodiversity and sensitivity of the environment. Microorganisms play an important role in pesticide degradation as they are able to utilize the biogenic elements from those compounds, as well as energy for their physiological processes. On the other hand, pesticides are more or less toxic substances that can have adverse effect on populations of microorganisms and prevent their development, reduce their abundance, deplete their taxonomic complexity and create communities with a lower level of diversity and reduced physiological activity.The article discusses complex interactions between pesticides and microorganisms in soil immediately after application and over the ensuing period. Data on changes in the abundance of some systematic and physiological groups of microorganisms, their microbial biomass and enzymatic activity caused under pesticide activity are discussed as indicators of these processes.

  2. Environmental exposure to pesticides and respiratory health

    Directory of Open Access Journals (Sweden)

    Ali Mamane

    2015-09-01

    Full Text Available Respiratory effects of environmental exposure to pesticides are debated. Here we aimed to review epidemiological studies published up until 2013, using the PubMed database. 20 studies dealing with respiratory health and non-occupational pesticide exposure were identified, 14 carried out on children and six on adults. In four out of nine studies in children with biological measurements, mothers' dichlorodiphenyldichloroethylene (DDE blood levels during pregnancy were associated with asthma and wheezing in young children. An association was also found between permethrin in indoor air during pregnancy and wheezing in children. A significant association between asthma and DDE measured in children's blood (aged 7–10 years was observed in one study. However, in three studies, no association was found between asthma or respiratory infections in children and pesticide levels in breast milk and/or infant blood. Lastly, in three out of four studies where post-natal pesticide exposure of children was assessed by parental questionnaire an association with respiratory symptoms was found. Results of the fewer studies on pesticide environmental exposure and respiratory health of adults were much less conclusive: indeed, the associations observed were weak and often not significant. In conclusion, further studies are needed to confirm whether there is a respiratory risk associated with environmental exposure to pesticides.

  3. Occupational exposure to pesticides and respiratory health.

    Science.gov (United States)

    Mamane, Ali; Baldi, Isabelle; Tessier, Jean-François; Raherison, Chantal; Bouvier, Ghislaine

    2015-06-01

    This article aims to review the available literature regarding the link between occupational exposure to pesticides and respiratory symptoms or diseases. Identification of epidemiological studies was performed using PubMed. 41 articles were included, 36 regarding agricultural workers and five regarding industry workers. Among the 15 cross-sectional studies focusing on respiratory symptoms and agricultural pesticide exposure, 12 found significant associations with chronic cough, wheeze, dyspnoea, breathlessness or chest tightness. All four studies on asthma found a relationship with occupational exposure, as did all three studies on chronic bronchitis. The four studies that performed spirometry reported impaired respiratory function linked to pesticide exposure, suggestive of either obstructive or restrictive syndrome according to the chemical class of pesticide. 12 papers reported results from cohort studies. Three out of nine found a significant relationship with increased risk of wheeze, five out of nine with asthma and three out of three with chronic bronchitis. In workers employed in pesticide production, elevated risks of chronic obstructive pulmonary disease (two studies out of three) and impaired respiratory function suggestive of an obstructive syndrome (two studies out of two) were reported. In conclusion, this article suggests that occupational exposure to pesticides is associated with an increased risk of respiratory symptoms, asthma and chronic bronchitis, but the causal relationship is still under debate.

  4. Characterizing pesticide dissipation in food crops

    DEFF Research Database (Denmark)

    Fantke, Peter; Juraske, R.; Jolliet, O.

    2013-01-01

    Ingestion of residues via consumption of food crops is the predominant exposure route of the general population toward pesticides. However, pesticide dissipation in crops constitutes a main source of uncertainty in estimating residues in harvested crop parts and subsequent human exposure. Neverth......Ingestion of residues via consumption of food crops is the predominant exposure route of the general population toward pesticides. However, pesticide dissipation in crops constitutes a main source of uncertainty in estimating residues in harvested crop parts and subsequent human exposure....... Nevertheless, dissipation is a key mechanism in models assessing pesticide distribution in the cropenvironment and the magnitude of residues in harvest. We provide a consistent framework for characterizing pesticide dissipation in food crops for use in modeling approaches applied in health risk and impact...... assessment. We collected 4,482 unique dissipation half-lives for 341 substances applied to 182 different crop species and fully characterize these data by describing their variance, distribution and uncertainty as well as by identifying the influence of substance, crop and environmental characteristics. We...

  5. Occupational exposure to pesticides and respiratory health

    Directory of Open Access Journals (Sweden)

    Ali Mamane

    2015-06-01

    Full Text Available This article aims to review the available literature regarding the link between occupational exposure to pesticides and respiratory symptoms or diseases. Identification of epidemiological studies was performed using PubMed. 41 articles were included, 36 regarding agricultural workers and five regarding industry workers. Among the 15 cross-sectional studies focusing on respiratory symptoms and agricultural pesticide exposure, 12 found significant associations with chronic cough, wheeze, dyspnoea, breathlessness or chest tightness. All four studies on asthma found a relationship with occupational exposure, as did all three studies on chronic bronchitis. The four studies that performed spirometry reported impaired respiratory function linked to pesticide exposure, suggestive of either obstructive or restrictive syndrome according to the chemical class of pesticide. 12 papers reported results from cohort studies. Three out of nine found a significant relationship with increased risk of wheeze, five out of nine with asthma and three out of three with chronic bronchitis. In workers employed in pesticide production, elevated risks of chronic obstructive pulmonary disease (two studies out of three and impaired respiratory function suggestive of an obstructive syndrome (two studies out of two were reported. In conclusion, this article suggests that occupational exposure to pesticides is associated with an increased risk of respiratory symptoms, asthma and chronic bronchitis, but the causal relationship is still under debate.

  6. Chlorination of organophosphorus pesticides in natural waters.

    Science.gov (United States)

    Acero, Juan L; Benítez, F Javier; Real, Francisco J; González, Manuel

    2008-05-01

    Unknown second-order rate constants for the reactions of three organophosphorus pesticides (chlorpyrifos, chlorfenvinfos and diazinon) with chlorine were determined in the present study, and the influence of pH and temperature was established. It was found that an increase in the pH provides a negative effect on the pesticides degradation rates. Apparent second-order rate constants at 20 degrees C and pH 7 were determined to be 110.9, 0.004 and 191.6 M(-1) s(-1) for chlorpyrifos, chlorfenvinfos and diazinon, respectively. A higher reactivity of chlorine with the phosphorothioate group (chlorpyrifos and diazinon) than with the phosphate moiety (chlorfenvinfos) could explain these results. Intrinsic rate constant for the elementary reactions of chlorine species with chlorpyrifos and diazinon were also calculated, leading to the conclusion that the reaction between hypochlorous acid and the pesticide is predominant at neutral pH. The elimination of these pesticides in surface waters was also investigated. A chlorine dose of 2.5 mg L(-1) was enough to oxidize chlorpyrifos and diazinon almost completely, with a formation of trihalomethanes below the EU standard for drinking water. However, the removal of chlorfenvinfos was not appreciable. Therefore, chlorination is a feasible option for the removal of organophosphorus pesticides with phosphorothioate group during oxidation and disinfection processes, but not for the elimination of pesticides with phosphate moiety.

  7. Cationically polymerizable monomers derived from renewable sources

    Energy Technology Data Exchange (ETDEWEB)

    Crivello, J.V.

    1992-10-01

    The objectives of this project are to design and synthesize novel monomers which orginate from renewable biological sources and to carry out their rapid, efficient, pollution-free and energy efficient cationic polymerization to useful products under the influence of ultraviolet light or heat. A summary of the results of the past year's research on cationically polymerizable monomers derived from renewable sources is presented. Three major areas of investigation corresponding to the different classes of naturally occurring starting materials were investigated; epoxidized terpenes and natural rubber and vinyl ethers from alcohols and carbohydrates.

  8. Metalated Nitriles: Cation-Controlled Cyclizations

    Science.gov (United States)

    Fleming, Fraser F.; Wei, Yunjing; Liu, Wang; Zhang, Zhiyu

    2008-01-01

    Judicious choice of cation allows the selective cyclization of substituted γ-hydroxynitriles to trans- or cis-decalins and trans- or cis-bicyclo[5.4.0]-undecanes. The stereoselectivities are consistent with deprotonations generating two distinctly different metalated nitriles: an internally coordinated nitrile anion with BuLi, and a C-magnesiated nitrile with i-PrMgCl. Employing cations to control the geometry of metalated nitriles permits stereodivergent cyclizations with complete control over the stereochemistry of the quaternary, nitrile-bearing carbon. PMID:17579448

  9. Cation Effect on Copper Chemical Mechanical Polishing

    Institute of Scientific and Technical Information of China (English)

    WANG Liang-Yong; LIU Bo; SONG Zhi-Tang; FENG Song-Lin

    2009-01-01

    We examine the effect of cations in solutions containing benzotriazole (BTA) and H2O2 on copper chemical mechanical polishing (CMP). On the base of atomic force microscopy (AFM) and material removal rate (MRR) results, it is found that ammonia shows the highest MRR as well as good surface after CMP, while KOH demon-strates the worst performance. These results reveal a mechanism that sma//molecules with lone-pairs rather than molecules with steric effect and common inorganic cations are better for copper CMP process, which is indirectly confirmed by open circuit potential (OCP).

  10. Cation Effect on Copper Chemical Mechanical Polishing

    Science.gov (United States)

    Wang, Liang-Yong; Liu, Bo; Song, Zhi-Tang; Feng, Song-Lin

    2009-02-01

    We examine the effect of cations in solutions containing benzotriazole (BTA) and H2O2 on copper chemical mechanical polishing (CMP). On the base of atomic force microscopy (AFM) and material removal rate (MRR) results, it is found that ammonia shows the highest MRR as well as good surface after CMP, while KOH demonstrates the worst performance. These results reveal a mechanism that small molecules with lone-pairs rather than molecules with steric effect and common inorganic cations are better for copper CMP process, which is indirectly confirmed by open circuit potential (OCP).

  11. Cationically polymerizable monomers derived from renewable sources

    Energy Technology Data Exchange (ETDEWEB)

    Crivello, J.V.

    1992-10-01

    The objectives of this project are to design and synthesize novel monomers which orginate from renewable biological sources and to carry out their rapid, efficient, pollution-free and energy efficient cationic polymerization to useful products under the influence of ultraviolet light or heat. A summary of the results of the past year's research on cationically polymerizable monomers derived from renewable sources is presented. Three major areas of investigation corresponding to the different classes of naturally occurring starting materials were investigated; epoxidized terpenes and natural rubber and vinyl ethers from alcohols and carbohydrates.

  12. Drosophila TRPML forms PI(3,5)P2-activated cation channels in both endolysosomes and plasma membrane.

    Science.gov (United States)

    Feng, Xinghua; Huang, Yu; Lu, Yungang; Xiong, Jian; Wong, Ching-On; Yang, Pu; Xia, Jintang; Chen, De; Du, Guangwei; Venkatachalam, Kartik; Xia, Xuefeng; Zhu, Michael X

    2014-02-14

    Transient Receptor Potential mucolipin (TRPML) channels are implicated in endolysosomal trafficking, lysosomal Ca(2+) and Fe(2+) release, lysosomal biogenesis, and autophagy. Mutations in human TRPML1 cause the lysosome storage disease, mucolipidosis type IV (MLIV). Unlike vertebrates, which express three TRPML genes, TRPML1-3, the Drosophila genome encodes a single trpml gene. Although the trpml-deficient flies exhibit cellular defects similar to those in mammalian TRPML1 mutants, the biophysical properties of Drosophila TRPML channel remained uncharacterized. Here, we show that transgenic expression of human TRPML1 in the neurons of Drosophila trpml mutants partially suppressed the pupal lethality phenotype. When expressed in HEK293 cells, Drosophila TRPML was localized in both endolysosomes and plasma membrane and was activated by phosphatidylinositol 3,5-bisphosphate (PI(3,5)P2) applied to the cytoplasmic side in whole lysosomes and inside-out patches excised from plasma membrane. The PI(3,5)P2-evoked currents were blocked by phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2), but not other phosphoinositides. Using TRPML A487P, which mimics the varitint-waddler (Va) mutant of mouse TRPML3 with constitutive whole-cell currents, we show that TRPML is biphasically regulated by extracytosolic pH, with an optimal pH about 0.6 pH unit higher than that of human TRPML1. In addition to monovalent cations, TRPML exhibits high permeability to Ca(2+), Mn(2+), and Fe(2+), but not Fe(3+). The TRPML currents were inhibited by trivalent cations Fe(3+), La(3+), and Gd(3+). These features resemble more closely to mammalian TRPML1 than TRPML2 and TRPML3, but with some obvious differences. Together, our data support the use of Drosophila for assessing functional significance of TRPML1 in cell physiology.

  13. Cationic dialkylarylphosphates: a new family of bio-inspired cationic lipids for gene delivery.

    Science.gov (United States)

    Le Corre, Stéphanie S; Belmadi, Nawal; Berchel, Mathieu; Le Gall, Tony; Haelters, Jean-Pierre; Lehn, Pierre; Montier, Tristan; Jaffrès, Paul-Alain

    2015-01-28

    In this work that aims to synthesize and evaluate new cationic lipids as vectors for gene delivery, we report the synthesis of a series of cationic lipids in which a phosphate functional group acts as a linker to assemble on a molecular scale, two lipid chains and one cationic polar head. The mono or dicationic moiety is connected to the phosphate group by an aryl spacer. In this work, two synthesis strategies were evaluated. The first used the Atherton-Todd coupling reaction to introduce a phenolic derivative to dioleylphosphite. The second strategy used a sequential addition of lipid alcohol and a phenolic derivative on POCl3. The two methods are efficient, but the latter allows larger yields. Different polar head groups were introduced, thus producing amphiphilic compounds possessing either one permanent (N-methyl-imidazolium, pyridinium, trimethylammonium) or two permanent cationic charges. All these cationic lipids were formulated as liposomal solutions and characterized (size and zeta potential). They formed stable liposomal solutions both in water (at pH 7.0) and in a weakly acidic medium (at pH 5.5). Finally, this new generation of cationic lipids was used to deliver DNA into various human-derived epithelial cells cultured in vitro. Compared with Lipofectamine used as a reference commercial lipofection reagent, some cationic dialkylarylphosphates were able to demonstrate potent gene transfer abilities, and noteworthily, monocationic derivatives were much more efficient than dicationic analogues.

  14. Prioritizing pesticide compounds for analytical methods development

    Science.gov (United States)

    Norman, Julia E.; Kuivila, Kathryn; Nowell, Lisa H.

    2012-01-01

    The U.S. Geological Survey (USGS) has a periodic need to re-evaluate pesticide compounds in terms of priorities for inclusion in monitoring and studies and, thus, must also assess the current analytical capabilities for pesticide detection. To meet this need, a strategy has been developed to prioritize pesticides and degradates for analytical methods development. Screening procedures were developed to separately prioritize pesticide compounds in water and sediment. The procedures evaluate pesticide compounds in existing USGS analytical methods for water and sediment and compounds for which recent agricultural-use information was available. Measured occurrence (detection frequency and concentrations) in water and sediment, predicted concentrations in water and predicted likelihood of occurrence in sediment, potential toxicity to aquatic life or humans, and priorities of other agencies or organizations, regulatory or otherwise, were considered. Several existing strategies for prioritizing chemicals for various purposes were reviewed, including those that identify and prioritize persistent, bioaccumulative, and toxic compounds, and those that determine candidates for future regulation of drinking-water contaminants. The systematic procedures developed and used in this study rely on concepts common to many previously established strategies. The evaluation of pesticide compounds resulted in the classification of compounds into three groups: Tier 1 for high priority compounds, Tier 2 for moderate priority compounds, and Tier 3 for low priority compounds. For water, a total of 247 pesticide compounds were classified as Tier 1 and, thus, are high priority for inclusion in analytical methods for monitoring and studies. Of these, about three-quarters are included in some USGS analytical method; however, many of these compounds are included on research methods that are expensive and for which there are few data on environmental samples. The remaining quarter of Tier 1

  15. A new crop of concerns: Congress investigates pesticide safety.

    Science.gov (United States)

    Taylor, D A

    2000-09-01

    A March 2000 report by the General Accounting Office, Pesticides: Improvements Needed to Ensure the Safety of Farmworkers and Their Children, states that much remains unknown about the risks faced by children in agriculture, and that enforcement of pesticide protection standards for farmworkers is patchy and unsystematic. Many cases of farmworkers' pesticide-related illnesses go unreported, leaving health workers with an inadequate basis for tracking patterns and fine-tuning pesticide standards, says the report. In addition, children are known to be more vulnerable to the effects of pesticides, but there is a lack of data regarding children's exposures and the precise effects of pesticides on children's health.

  16. Increasing pesticide-resistant ectoparasitic infections may increase pesticide poisoning risks in children.

    Science.gov (United States)

    Diaz, James H

    2008-01-01

    Head louse and scabies mite infestations are common among pre-school and school-age children, and topical pesticides are frequently prescribed to treat such conditions. Ectoparasite resistance to the safest and most commonly prescribed pyrethrin/pyrethroid pesticides for ectoparasitic infections has, however, been increasing since the 1980s. The increasing resistance of these arthropods to the safest pesticides may lead to greater use of more toxic, alternative pesticides to control infestations and to prevent institutional outbreaks. MEDLINE and Cochrane searches, 1966-2008, were conducted to assess the impact of increasing pesticide resistance on prescribing practices for ectoparasitic infections and to describe the evolving global epidemiology of pediatric poisonings by more toxic pediculicides and miticides, including carbamates, organochlorines, and organophosphates. Pharmacists, physicians, and poison control personnel should be fully informed about increasing pesticide resistance among the most commonly encountered ectoparasites of children and the institutionalized and be prepared to prevent and to treat accidental home and institutional pesticide poisonings with more toxic pesticides.

  17. 76 FR 552 - Pesticides; Availability of Pesticide Registration Notice Regarding the Residential Exposure...

    Science.gov (United States)

    2011-01-05

    ... of the Residential Exposure Joint Venture, L.L.C. This PR Notice (PR Notice 2011-1) issued by the... AGENCY Pesticides; Availability of Pesticide Registration Notice Regarding the Residential Exposure Joint Venture AGENCY: Environmental Protection Agency (EPA). ACTION: Notice. SUMMARY: The Agency is...

  18. Spatial and temporal analysis of pesticides concentrations in surface water: Pesticides atlas

    NARCIS (Netherlands)

    Vijver, M.G.; Zelfde, van 't M.; Tamis, W.L.M.; Snoo, de G.R.

    2008-01-01

    Dutch water boards have a well-established program for monitoring pesticide contamination of surface waters. These monitoring data have been processed into a graphic format accessible online and designed to provide insight into pesticide presence in Dutch surface waters and trends over time: the

  19. Biosensor technology for pesticides--a review.

    Science.gov (United States)

    Verma, Neelam; Bhardwaj, Atul

    2015-03-01

    Pesticides, due to their lucrative outcomes, are majorly implicated in agricultural fields for crop production enhancement. Due to their pest removal properties, pesticides of various classes have been designed to persist in the environment over a longer duration after their application to achieve maximum effectiveness. Apart from their recalcitrant structure and agricultural benefits, pesticides also impose acute toxicological effects onto the other various life forms. Their accumulation in the living system may prove to be detrimental if established in higher concentrations. Thus, their prompt and accurate analysis is a crucial matter of concern. Conventional techniques like chromatographic techniques (HPLC, GC, etc.) used for pesticides detection are associated with various limitations like stumpy sensitivity and efficiency, time consumption, laboriousity, requirement of expensive equipments and highly trained technicians, and many more. So there is a need to recruit the methods which can detect these neurotoxic compounds sensitively, selectively, rapidly, and easily in the field. Present work is a brief review of the pesticide effects, their current usage scenario, permissible limits in various food stuffs and 21st century advancements of biosensor technology for pesticide detection. Due to their exceptional performance capabilities, easiness in operation and on-site working, numerous biosensors have been developed for bio-monitoring of various environmental samples for pesticide evaluation immensely throughout the globe. Till date, based on sensing element (enzyme based, antibody based, etc.) and type of detection method used (Electrochemical, optical, and piezoelectric, etc.), a number of biosensors have been developed for pesticide detection. In present communication, authors have summarized 21st century's approaches of biosensor technology for pesticide detection such as enzyme-based biosensors, immunosensors, aptamers, molecularly imprinted polymers, and

  20. Cation Selectivity in Biological Cation Channels Using Experimental Structural Information and Statistical Mechanical Simulation.

    Science.gov (United States)

    Finnerty, Justin John; Peyser, Alexander; Carloni, Paolo

    2015-01-01

    Cation selective channels constitute the gate for ion currents through the cell membrane. Here we present an improved statistical mechanical model based on atomistic structural information, cation hydration state and without tuned parameters that reproduces the selectivity of biological Na+ and Ca2+ ion channels. The importance of the inclusion of step-wise cation hydration in these results confirms the essential role partial dehydration plays in the bacterial Na+ channels. The model, proven reliable against experimental data, could be straightforwardly used for designing Na+ and Ca2+ selective nanopores.

  1. 40 CFR 158.2170 - Experimental use permit data requirements-microbial pesticides.

    Science.gov (United States)

    2010-07-01

    ... requirements-microbial pesticides. 158.2170 Section 158.2170 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Microbial Pesticides § 158.2170 Experimental use permit data requirements—microbial pesticides. (a) For all microbial pesticides. (1)...

  2. Controlled Cationic Polymerization of N-Vinylcarbazol

    NARCIS (Netherlands)

    Nuyken, O.; Rieß, G.; Loontjens, J.A.

    1995-01-01

    Cationic polymerization of N-Vinylcarbazol (NVC) was initiated with 1-iodo-1-(2-methylpropyloxy)ethane in the presence of N(n-Bu)4ClO4 and without addition of this activator. Furthermore, 1-chloro-1-(2-methylpropyloxy) ethane, with and without activator has been applied as initiator for NVC. These i

  3. Anionic/cationic complexes in hair care.

    Science.gov (United States)

    O'Lenick, Tony

    2011-01-01

    The formulation of cosmetic products is always more complicated than studying the individual components in aqueous solution. This is because there are numerous interactions between the components, which make the formulation truly more than the sum of the parts. This article will look at interactions between anionic and cationic surfactants and offer insights into how to use these interactions advantageously in making formulations.

  4. Resonance raman studies of phenylcyclopropane radical cations

    NARCIS (Netherlands)

    Godbout, J.T.; Zuilhof, H.; Heim, G.; Gould, I.R.; Goodman, J.L.; Dinnocenzo, J.P.; Myers Kelley, A.

    2000-01-01

    Resonance Raman spectra of the radical cations of phenylcyclopropane and trans-1-phenyl-2-methylcyclopropane are reported. A near-UV pump pulse excites a photosensitizer which oxidizes the species of interest, and a visible probe pulse delayed by 35 ns obtains the spectrum of the radical ion. The tr

  5. Mixed cation effect in sodium aluminosilicate glasses

    DEFF Research Database (Denmark)

    Kjeldsen, Jonas; Smedskjær, Morten Mattrup; Mauro, John C.

    , network structure, and the resistances associated with the deformation processes in mixed cation glasses by partially substituting magnesium for calcium and calcium for lithium in sodium aluminosilicate glasses. We use Raman and 27Al NMR spectroscopies to obtain insights into the structural...

  6. Simultaneous anion and cation mobility in polypyrrole

    DEFF Research Database (Denmark)

    Skaarup, Steen; Bay, Lasse; Vidanapathirana, K.;

    2003-01-01

    Polypyrrole (PPy) polymer films permanently doped with large, immobile anion dodecyl benzene sulfonate (DBS) have been characterized by cyclic voltammetry in order to clarify the roles of cations and anions in the aqueous electrolyte as mobile ions in the film. Aqueous solutions of 0.05-0.1 M...... alkali metal chlorides as well as BaCl2, NaBr and (CH3CH2CH2)(4)NBr were used to investigate the effects of both the ionic charge, size and shape. In 1: 1 electrolytes using small ions only three peaks are present: a sharp cathodic peak at ca. - 0.6 V vs, SCE representing both the insertion of cations...... complicating reproducibility when employing PPy(DBS) polymers as actuators. When the cation is doubly charged, it enters the film less readily, and anions dominate the mobility. Using a large and bulky cation switches the mechanism to apparently total anion motion. The changes in area of the three peaks...

  7. Cationic lipids and cationic ligands induce DNA helix denaturation: detection of single stranded regions by KMnO4 probing.

    Science.gov (United States)

    Prasad, T K; Gopal, Vijaya; Rao, N Madhusudhana

    2003-09-25

    Cationic lipids and cationic polymers are widely used in gene delivery. Using 1,2-dioleoyl-3-trimethylammonium-propane (DOTAP) as a cationic lipid, we have investigated the stability of the DNA in DOTAP:DNA complexes by probing with potassium permanganate (KMnO4). Interestingly, thymidines followed by a purine showed higher susceptibility to cationic ligand-mediated melting. Similar studies performed with other water-soluble cationic ligands such as polylysine, protamine sulfate and polyethyleneimine also demonstrated melting of the DNA but with variations. Small cations such as spermine and spermidine and a cationic detergent, cetyl trimethylammonium bromide, also rendered the DNA susceptible to modification by KMnO4. The data presented here provide direct proof for melting of DNA upon interaction with cationic lipids. Structural changes subsequent to binding of cationic lipids/ligands to DNA may lead to instability and formation of DNA bubbles in double-stranded DNA.

  8. Watershed Regressions for Pesticides (WARP) models for predicting stream concentrations of multiple pesticides

    Science.gov (United States)

    Stone, Wesley W.; Crawford, Charles G.; Gilliom, Robert J.

    2013-01-01

    Watershed Regressions for Pesticides for multiple pesticides (WARP-MP) are statistical models developed to predict concentration statistics for a wide range of pesticides in unmonitored streams. The WARP-MP models use the national atrazine WARP models in conjunction with an adjustment factor for each additional pesticide. The WARP-MP models perform best for pesticides with application timing and methods similar to those used with atrazine. For other pesticides, WARP-MP models tend to overpredict concentration statistics for the model development sites. For WARP and WARP-MP, the less-than-ideal sampling frequency for the model development sites leads to underestimation of the shorter-duration concentration; hence, the WARP models tend to underpredict 4- and 21-d maximum moving-average concentrations, with median errors ranging from 9 to 38% As a result of this sampling bias, pesticides that performed well with the model development sites are expected to have predictions that are biased low for these shorter-duration concentration statistics. The overprediction by WARP-MP apparent for some of the pesticides is variably offset by underestimation of the model development concentration statistics. Of the 112 pesticides used in the WARP-MP application to stream segments nationwide, 25 were predicted to have concentration statistics with a 50% or greater probability of exceeding one or more aquatic life benchmarks in one or more stream segments. Geographically, many of the modeled streams in the Corn Belt Region were predicted to have one or more pesticides that exceeded an aquatic life benchmark during 2009, indicating the potential vulnerability of streams in this region.

  9. Emission of pesticides into the air

    Science.gov (United States)

    Van Den, Berg; Kubiak, R.; Benjey, W.G.; Majewski, M.S.; Yates, S.R.; Reeves, G.L.; Smelt, J.H.; Van Der Linden, A. M. A.

    1999-01-01

    During and after the application of a pesticide in agriculture, a substantial fraction of the dosage may enter the atmosphere and be transported over varying distances downwind of the target. The rate and extent of the emission during application, predominantly as spray particle drift, depends primarily on the application method (equipment and technique), the formulation and environmental conditions, whereas the emission after application depends primarily on the properties of the pesticide, soils, crops and environmental conditions. The fraction of the dosage that misses the target area may be high in some cases and more experimental data on this loss term are needed for various application types and weather conditions. Such data are necessary to test spray drift models, and for further model development and verification as well. Following application, the emission of soil fumigants and soil incorporated pesticides into the air can be measured and computed with reasonable accuracy, but further model development is needed to improve the reliability of the model predictions. For soil surface applied pesticides reliable measurement methods are available, but there is not yet a reliable model. Further model development is required which must be verified by field experiments. Few data are available on pesticide volatilization from plants and more field experiments are also needed to study the fate processes on the plants. Once this information is available, a model needs to be developed to predict the volatilization of pesticides from plants, which, again, should be verified with field measurements. For regional emission estimates, a link between data on the temporal and spatial pesticide use and a geographical information system for crops and soils with their characteristics is needed.

  10. Dendritic Cells Stimulated by Cationic Liposomes.

    Science.gov (United States)

    Vitor, Micaela Tamara; Bergami-Santos, Patrícia Cruz; Cruz, Karen Steponavicius Piedade; Pinho, Mariana Pereira; Barbuto, José Alexandre Marzagão; De La Torre, Lucimara Gaziola

    2016-01-01

    Immunotherapy of cancer aims to harness the immune system to detect and destroy cancer cells. To induce an immune response against cancer, activated dendritic cells (DCs) must present tumor antigens to T lymphocytes of patients. However, cancer patients' DCs are frequently defective, therefore, they are prone to induce rather tolerance than immune responses. In this context, loading tumor antigens into DCs and, at the same time, activating these cells, is a tempting goal within the field. Thus, we investigated the effects of cationic liposomes on the DCs differentiation/maturation, evaluating their surface phenotype and ability to stimulate T lymphocytes proliferation in vitro. The cationic liposomes composed by egg phosphatidylcholine, 1,2-dioleoyl-3-trimethylammonium propane and 1,2-dioleoylphosphatidylethanolamine (50/25/25% molar) were prepared by the thin film method followed by extrusion (65 nm, polydispersity of 0.13) and by the dehydration-rehydration method (95% of the population 107 nm, polydispersity of 0.52). The phenotypic analysis of dendritic cells and the analysis of T lymphocyte proliferation were performed by flow cytometry and showed that both cationic liposomes were incorporated and activated dendritic cells. Extruded liposomes were better incorporated and induced higher CD86 expression for dendritic cells than dehydrated-rehydrated vesicles. Furthermore, dendritic cells which internalized extruded liposomes also provided stronger T lymphocyte stimulation. Thus, cationic liposomes with a smaller size and polydispersity seem to be better incorporated by dendritic cells. Hence, these cationic liposomes could be used as a potential tool in further cancer immunotherapy strategies and contribute to new strategies in immunotherapy.

  11. Energy-resolved collision-induced dissociation studies of 1,10-phenanthroline complexes of the late first-row divalent transition metal cations: determination of the third sequential binding energies.

    Science.gov (United States)

    Nose, Holliness; Chen, Yu; Rodgers, M T

    2013-05-23

    The third sequential binding energies of the late first-row divalent transition metal cations to 1,10-phenanthroline (Phen) are determined by energy-resolved collision-induced dissociation (CID) techniques using a guided ion beam tandem mass spectrometer. Five late first-row transition metal cations in their +2 oxidation states are examined including: Fe(2+), Co(2+), Ni(2+), Cu(2+), and Zn(2+). The kinetic energy dependent CID cross sections for loss of an intact Phen ligand from the M(2+)(Phen)3 complexes are modeled to obtain 0 and 298 K bond dissociation energies (BDEs) after accounting for the effects of the internal energy of the complexes, multiple ion-neutral collisions, and unimolecular decay rates. Electronic structure theory calculations at the B3LYP, BHandHLYP, and M06 levels of theory are employed to determine the structures and theoretical estimates for the first, second, and third sequential BDEs of the M(2+)(Phen)x complexes. B3LYP was found to deliver results that are most consistent with the measured values. Periodic trends in the binding of these complexes are examined and compared to the analogous complexes to the late first-row monovalent transition metal cations, Co(+), Ni(+), Cu(+), and Zn(+), previously investigated.

  12. 75 FR 62387 - Pesticide Product Registrations; Conditional Approval

    Science.gov (United States)

    2010-10-08

    ... AGENCY Pesticide Product Registrations; Conditional Approval AGENCY: Environmental Protection Agency (EPA...., to conditionally register the pesticide products Paladin Technical, Paladin, and Paladin EC... provisions of section 3(c)(7)(C) of the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA),...

  13. 76 FR 54230 - Product Cancellation Order for Certain Pesticide Registrations

    Science.gov (United States)

    2011-08-31

    ... 5126, Vadosta, GA 31603-5126. CA020006 Pan American Seed Co., P.O. Box 506, Lompoc, CA 93438. ID060002.... Peter Caulkins, Acting Director, Pesticide Re-evaluation Division, Office of Pesticide Programs. BILLING...

  14. New EPA Guidance for Testing Pesticides Will Reduce Animal Testing

    Science.gov (United States)

    EPA is issuing guidance for requesting waivers of acute dermal toxicity testing requirements for pesticide formulations, which will lead to fewer animal tests for acute dermal toxicity for pesticides.

  15. Protections for Subjects in Human Research with Pesticides

    Science.gov (United States)

    All pesticide research using human subjects must meet our strict protective standards before we would consider using them in evaluating pesticides. EPA's regulation “Protections for Subjects in Human Research” was promulgated in 2006 and amended in 2013.

  16. TRANSFER EFFICIENCES OF PESTICIDES FROM HOUSEHOLD CERAMIC TILE TO FOODS

    Science.gov (United States)

    Traditional assessments of pesticide exposure through diet have focused on contamination during production (e.g., pesticides in agriculture). However, recent residential monitoring studies have demonstrated that a significant portion of total exposure to infants and children ...

  17. Metabolism of pesticides after dermal exposure to amphibians

    Science.gov (United States)

    Understanding how pesticide exposure to non-target species influences toxicity is necessary to accurately assess the ecological risks these compounds pose. Aquatic, terrestrial, and arboreal amphibians are often exposed to pesticides during their agricultural application resultin...

  18. Pesticide use knowledge and practices: a gender differences in Nepal.

    Science.gov (United States)

    Atreya, Kishor

    2007-06-01

    It is important to understand gender difference on pesticide use knowledge, attitude and practices for identifying pesticide risks by gender and to recommend more gender-sensitive programs. However, very few studies have been conducted so far in Nepal. This study, thus, interviewed a total of 325 males and 109 females during 2005 to assess gender differences on pesticide use knowledge, attitude and practices. More than 50% females had never been to school and only Pest Management (IPM). Almost all males and females did not smoke, drink and eat during pesticides application and also believed that pesticides are harmful to human health, livestock, plant diversity and their environment. However, there were gender differences on household decision on pesticides to be used (phigher risk due to lower level of pesticide use safety and awareness. It is strongly recommended to initiate gender-sensitive educational and awareness activities, especially on pesticide use practices and safety precautions.

  19. Test Guideline Methods for Bed Bug Pesticide Products Now Available

    Science.gov (United States)

    EPA’s final test guidelines, 810.3900 - Laboratory Product Performance Testing Methods for Bed Bug Pesticide Products, provides recommendations for the design and execution of laboratory studies to evaluate the performance of pesticide products.

  20. Funding Opportunity Announcement: Pesticide Safety Education Funds Management Program

    Science.gov (United States)

    EPA is soliciting proposals from eligible applicants to establish and administer a national subaward program in support of pesticide applicator education and training for certified applicators of restricted use pesticides.

  1. [A model study of pesticide biodegradation in soil].

    Science.gov (United States)

    Bieganska, J

    2007-01-01

    This study addresses the efficiency of microbial preparations to degrade pesticide residues in soil. A method to degrade pesticides DNOC and pendimethalin using Pseudomonas and Arthrobacter bacteria with a fertilizer is described.

  2. Avoid Counterfeit Pesticide Products for Dogs and Cats

    Science.gov (United States)

    EPA is aware of counterfeit pet pesticides designed to look like legitimately registered pesticide products. The information on this page is intended to help consumers avoid unregistered pet products.

  3. Effect of Clay Mineralogy and Exchangeable Cations on Permeability of Saudi Sandstone Reservoirs Effet de la minéralogie des argiles et des cations échangeables sur la perméabilité des réservoirs gréseux d'Arabie Saoudite

    Directory of Open Access Journals (Sweden)

    Dahab A. S.

    2006-11-01

    Full Text Available Reservoir rocks are susceptible to formation damage during secondary recovery operations due to the particular mineralogical, textural and electrochemical properties of the clay minerals they contain. This damage can be explained by the swelling of indigeneous clays present, resulting in the constricting of pores, or by the dispersion of indigeneous nonswelling particle rearrangements during fluid flow, resulting in the plugging of the pore system, or by a combination of the two. This article describes a laboratory study showing the effect of clay mineralogy on the permeability of actual Saudi sandstone reservoirs during water flooding operations. The study shows that the permeability damage of Saudi sandstone reservoirs depends upon the amount of swelling clays and exchangeable ions as well as on the nature of these ions. Monovalent cations cause more damage than multivalent ones but within the same group of metals, those with smaller atomic mass cause more damage. Les roches réservoirs peuvent être endommagées pendant les opérations de récupération secondaire à cause des propriétés minéralogiques, texturales et électrochimiques particulières des minéraux argileux qu'elles contiennent. Cet endommagement peut s'expliquer, soit par le gonflement des argiles qui conduit à un rétrécissement des pores, soit par la migration de particules non gonflantes pendant l'écoulement des fluides qui entraîne le colmatage des milieux poreux, soit par une combinaison des deux mécanismes. Cet article présente une étude de laboratoire montrant l'effet de la minéralogie des argiles sur la perméabilité des roches réservoirs réelles d'Arabie Saoudite pendant des opérations d'injection d'eau. L'étude montre que l'endommagement de la perméabilité des roches réservoirs d'Arabie Saoudite dépend de la quantité d'argiles gonflantes et d'ions échangeables, ainsi que de la nature de ces ions. Les cations monovalents provoquent plus d

  4. Compound specific isotope analysis of organophosphorus pesticides.

    Science.gov (United States)

    Wu, Langping; Yao, Jun; Trebse, Polonca; Zhang, Ning; Richnow, Hans H

    2014-09-01

    Compound-specific isotope analysis (CSIA) has been established as a tool to study the environmental fate of a wide range of contaminants. In this study, CSIA was developed to analyse the stable carbon isotope signatures of the widely used organophosphorus pesticides: dichlorvos, omethoate and dimethoate. The linearity of the GC-C-IRMS system was tested for target pesticides and led to an acceptable isotope composition within the uncertainty of the instrument. In order to assess the accuracy of the developed method, the effect of the evaporation procedure on measured carbon isotope composition (δ(13)C) values was studied and showed that concentration by evaporation of solvents had no significant isotope effect. The CSIA was then applied to investigate isotope fractionation of the hydrolysis and photolysis of selected pesticides. The carbon isotope fractionation of tested pesticides was quantified by the Rayleigh model, which revealed a bulk enrichment factor (ε) of -0.2±0.1‰ for hydrolysis of dichlorvos, -1.0±0.1‰ and -3.7±1.1‰ for hydrolysis and photolysis of dimethoate respectively. This study is a first step towards the application of CSIA to trace the transport and degradation of organophosphorus pesticides in the environment.

  5. THE CATIONIC ADDITIVES USED IN COATED INK-JET PAPER

    Institute of Scientific and Technical Information of China (English)

    Dongmei Yu; Chuanshan Zhao; Kefu Chen

    2004-01-01

    This study investigated the effects of several different cationic additives on the viscosity 、zeta potential and printing properties of the ink-jet coating. The cationic additives have greatly improved sheet's gloss and printabilities.

  6. Bithiophene radical cation: Resonance Raman spectroscopy and molecular orbital calculations

    DEFF Research Database (Denmark)

    Grage, M.M.-L.; Keszthelyi, T.; Offersgaard, J.F.

    1998-01-01

    The resonance Raman spectrum of the photogenerated radical cation of bithiophene is reported. The bithiophene radical cation was produced via a photoinduced electron transfer reaction between excited bithiophene and the electron acceptor fumaronitrile in a room temperature acetonitrile solution a...

  7. Ion dynamics in cationic lipid bilayer systems in saline solutions

    DEFF Research Database (Denmark)

    Miettinen, Markus S; Gurtovenko, Andrey A; Vattulainen, Ilpo

    2009-01-01

    mixture of cationic dimyristoyltrimethylammoniumpropane (DMTAP) and zwitterionic (neutral) dimyristoylphosphatidylcholine (DMPC) lipids. Using atomistic molecular dynamics simulations, we address the effects of bilayer composition (cationic to zwitterionic lipid fraction) and of NaCl electrolyte...

  8. Public Health Implications of Pesticide Residues in Meat

    OpenAIRE

    Jadhav V.J. and Waskar V.S.

    2011-01-01

    Use of pesticides in India began in 1948 when DDT was imported for malaria control and BHC for locust control. Since then various synthetic pesticides are used for protection of crops and public health. The persistence nature of some of these pesticides led to their accumulation in animal tissues and subsequently causes human dietary exposure to these pesticides through consumption of animal products viz. meat, milk, eggs and seafoods. Scientific evidence suggest that even such low dose but l...

  9. Procedures for Removal of Pesticides from the Environment

    OpenAIRE

    Đokić, M.; Bilandžić, N.; Briški, F.

    2012-01-01

    Pesticides are widely used in food production, and it is believed that more than 1000 types of pesticides are in use. Organochlorines and organophosphorous pesticides are used in large quantities due to their efficacy and low cost. These persistent organic pollutants remain in the soil, silt, and sediment long after application, and enter into watercourses, finding their way directly into the food chain. Today, the following procedures are used to remove pesticides from polluted localities: l...

  10. Phosphate absorption and efflux of three ectomycorrhizal fungi as affected by external phosphate, cation and carbohydrate concentrations.

    Science.gov (United States)

    Bücking, Heike

    2004-06-01

    A prerequisite for symbiotic phosphate transfer in an ectomycorrhizal (ECM) association is hypothesized to be conditions in the interface between both symbiotic partners, that either promote the release of inorganic phosphate (P) from the Hartig net into the interfacial apoplast and/or decrease the fungal reabsorption from this location. To get more information about conditions, which might be involved in the regulation of P efflux or P reabsorption, the effect of various external conditions on 33P-orthophosphate (33P) uptake or efflux by axenic cultures of the ECM basidiomycetes Hebeloma crustliniforme, Amanita muscaria and Laccaria laccata was analysed. In short-time experiments the following external conditions were analysed: an external supply of (1) P in the preculture, (2) cations (0.1-100 mM K, 0.1-50 mM Na, Mg and Ca), and (3) carbohydrates (0.5-50 mM glucose, fructose or sucrose). The P absorption was generally reduced in cultures previously supplied with an abundant P supply and with increased P concentrations in their tissues. The P uptake was also affected by an external supply of cations, whereas carbohydrates had only a slight effect. Compared to Na, Mg and Ca, the P absorption by H. crustuliniforme and L. laccata was increased by 0.1 mM K in the labelling solution but decreased after a supply of 100 mM K and then did not differ from the other cation treatments. Compared to other cations, an addition of 50 mM Ca led to a decrease of P absorption by A. muscaria, whereas 50 mM Mg increased the P uptake by H. crustuliniforme. The P efflux from the fungi was affected by both the cation and carbohydrate concentration of the bathing solution. High concentrations of the monovalent cations K and Na (5 mM or 50 mM) in the bathing solution increased the P efflux by H. crustuliniforme (only Na) and L. laccata (K and Na), but had little effects on A. muscaria. By contrast, the same concentrations of the divalent cation Mg reduced the P efflux from all fungal

  11. 77 FR 75082 - Notice of Receipt of Several Pesticide Petitions Filed for Residues of Pesticide Chemicals in or...

    Science.gov (United States)

    2012-12-19

    ... environmental justice issues, the Agency seeks information on any groups or segments of the population who, as a... ingredient in pesticide formulations for a packaging film for unit dose packaging of pesticides and...

  12. Pesticide leaching through sandy and loamy fields e Long-term lessons learnt from the Danish Pesticide Leaching Assessment Programme

    DEFF Research Database (Denmark)

    Rosenbom, Annette Elisabeth; Olsen, Preben; Plauborg, Finn

    2015-01-01

    The European Union authorization procedure for pesticides includes assessment of the leaching risk posed by pesticides and their degradation products aimed at avoiding any unacceptable influence on the environment, in particular contamination of water, including drinking water and groundwater...

  13. Estimation of agricultural pesticide use in drainage basins using land cover maps and county pesticide data

    Science.gov (United States)

    Nakagaki, Naomi; Wolock, David M.

    2005-01-01

    A geographic information system (GIS) was used to estimate agricultural pesticide use in the drainage basins of streams that are studied as part of the U.S. Geological Survey?s National Water-Quality Assessment (NAWQA) Program. Drainage basin pesticide use estimates were computed by intersecting digital maps of drainage basin boundaries with an enhanced version of the National Land Cover Data 1992 combined with estimates of 1992 agricultural pesticide use in each United States county. This report presents the methods used to quantify agricultural pesticide use in drainage basins using a GIS and includes the estimates of atrazine use applied to row crops, small-grain crops, and fallow lands in 150 watersheds in the conterminous United States. Basin atrazine use estimates are presented to compare and analyze the results that were derived from 30-meter and 1-kilometer resolution land cover and county pesticide use data, and drainage basin boundaries at various grid cell resolutions. Comparisons of the basin atrazine use estimates derived from watershed boundaries, county pesticide use, and land cover data sets at different resolutions, indicated that overall differences were minor. The largest potential for differences in basin pesticide use estimates between those derived from the 30-meter and 1-kilometer resolution enhanced National Land Cover Data 1992 exists wherever there are abrupt agricultural land cover changes along the basin divide. Despite the limitations of the drainage basin pesticide use data described in this report, the basin estimates provide consistent and comparable indicators of agricultural pesticide application in surface-water drainage basins studied in the NAWQA Program.

  14. Microbial pesticides [data requirements for environmental risk assessment

    NARCIS (Netherlands)

    Mensink BJWG; Linders JBHJ; CSR

    1997-01-01

    The market for microbial pesticides is, though slowly, expanding. Therefore more research with these pesticides will be carried out in the near future, not only for agronomical and economical, but also for environmental reasons. As more chemical pesticides are going to be banned, microbial

  15. Do farmers internalise environmental spillovers of pesticides in production?

    NARCIS (Netherlands)

    Skevas, T.; Stefanou, S.E.; Oude Lansink, A.G.J.M.

    2013-01-01

    Pesticides are used in agriculture to protect crops from pests and diseases, with indiscriminate pesticide use having several adverse effects on the environment and human health. An important question is whether the environmental spillovers of pesticides also affect the farmers’ production environme

  16. Extraction of Pesticides from Plants using Solid Phase ...

    African Journals Online (AJOL)

    NICO

    that may render trace analysis of pesticide residues almost impossible. .... mixing. 100 µL of the internal standard stock solution was added to each mixture. ... graph. 2.5.2. Extraction of Pesticides from Plant Samples by QuEChERS. Pesticide ...

  17. 42 CFR 84.1156 - Pesticide respirators; performance requirements; general.

    Science.gov (United States)

    2010-10-01

    ... resistance will be measured in the facepiece, mouthpiece, hood, or helmet of a pesticide respirator mounted... allowable resistance requirements for pesticide respirators are as follows: Maximum Resistance Type of... 42 Public Health 1 2010-10-01 2010-10-01 false Pesticide respirators; performance...

  18. 29 CFR 1440.1 - Arbitration of pesticide data disputes.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 4 2010-07-01 2010-07-01 false Arbitration of pesticide data disputes. 1440.1 Section 1440... ARBITRATION OF PESTICIDE DATA DISPUTES § 1440.1 Arbitration of pesticide data disputes. (a) Persons requesting... in writing to the appropriate American Arbitration Association Regional Office. Such requests...

  19. From pesticides to genetically modified plants : history, economics and politics

    NARCIS (Netherlands)

    Zadoks, J.C.; Waibel, H.

    2000-01-01

    Two technologies of crop protection are compared, crop protection by pesticides and by Genetically Modified Plants (GMPs). The history of pesticides provides lessons relevant to the future of GMPs; (1) high pesticide usage is counter-productive, (2) the technology requires intensive regulation and

  20. 40 CFR 158.100 - Pesticide use patterns.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Pesticide use patterns. 158.100... DATA REQUIREMENTS FOR PESTICIDES How To Use Data Tables § 158.100 Pesticide use patterns. (a) General use patterns. There are six broad use categories used in the data tables. The six broad categories...

  1. 75 FR 35805 - Pesticide Product Registrations; Conditional Approvals

    Science.gov (United States)

    2010-06-23

    ... applications from Monsanto Company, 800 North Lindbergh Boulevard, St. Louis, MO 63167, to register pesticide... announced that Monsanto Company had submitted applications to register pesticide products containing the new... comment opposed granting Monsanto Company rights to produce, sell, or manufacture pesticide...

  2. Recognition and Management of Pesticide Poisonings. Third Edition.

    Science.gov (United States)

    Morgan, Donald P.

    This manual aids health professionals in recognizing and treating pesticide poisonings. Suggested treatments are appropriate for implementation in the small hospitals and clinics which usually receive the victims of pesticide poisoning. Classes of compounds covered include: (1) organophosphate cholinesterase-inhibiting pesticides; (2) carbamate…

  3. America's Growing Dilemma: Pesticides in Food and Water.

    Science.gov (United States)

    Strauss, Valerie; Sullivan, Monica, Ed.

    Public concern about the safety of continued reliance on pesticides in agricultural production is widespread and growing. The lack of understanding of how food is grown, the role of pesticides in food production, the risk assessment and regulatory processes and alternatives to pesticide use limits citizen participation in food safety debates and…

  4. From pesticides to genetically modified plants : history, economics and politics

    NARCIS (Netherlands)

    Zadoks, J.C.; Waibel, H.

    2000-01-01

    Two technologies of crop protection are compared, crop protection by pesticides and by Genetically Modified Plants (GMPs). The history of pesticides provides lessons relevant to the future of GMPs; (1) high pesticide usage is counter-productive, (2) the technology requires intensive regulation and (

  5. Do farmers internalise environmental spillovers of pesticides in production?

    NARCIS (Netherlands)

    Skevas, T.; Stefanou, S.E.; Oude Lansink, A.G.J.M.

    2013-01-01

    Pesticides are used in agriculture to protect crops from pests and diseases, with indiscriminate pesticide use having several adverse effects on the environment and human health. An important question is whether the environmental spillovers of pesticides also affect the farmers’ production

  6. Production of sulfonated cation-exchangers from petroleum asphaltites

    Energy Technology Data Exchange (ETDEWEB)

    Pokonova, Yu.V.; Pol' kin, G.B.; Proskuryakov, V.A.; Vinogradov, M.V.

    1982-02-10

    Continuing our studies of the preparation of products of practical value from asphaltite, a new by-product of oil refining, we obtained sulfonated cation-exchangers from a mixture of asphaltite and acid tar. It is shown that these cation-exchangers have good kinetic properties and are superior in thermal and thermohydrolytic stability to the commercial cation-exchange resin KU-2.

  7. Toxicity Studies on "840 Biologic Pesticide"

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    [Objective] "840 Biologic Pesticide" is a very effective biologic pesticide. It consists of Abamectin and celastrus angulatus. Toxicity study was aimed to provide scientific toxicological basis. [Methods] The acute toxicity test,Ames test,micronucleus test and testicle chromosome aberration test were done. [Results] The acute toxicity of single dose of "840 Biologic Pesticide" showed that acute oral LD50 for female and male rats are 4 300 and 4 280 mg/kg,and for female and male mice are 2 330 and 5 110 mg/kg,respectively. The dermal LD50 was >2 000 mg/kg for female and male rats. The mutagenesis studies indicated that Ames test,micronucleus test and testicle chromosome aberration test were negative. [Conclusion] Tested pesticidc belongs to low toticity grade.

  8. Improved indicators and monitoring of pesticide use

    DEFF Research Database (Denmark)

    Sørensen, Peter Borgen; Kjær, Christian; Kudsk, Per

      The goal for the new improved indicator, PestNaB (Pesticiders NaturBelastning), was to develop a valid indicator reflecting the potential risk for nature due to application of pesticides and based on available data set for Danish conditions. The focus is on risk in relation the nature close to......, and directly inside, the agricultural areas so this excludes the risk for contamination of groundwater and the human risk. Elements from existing indicators are combined in a way that can make optimal use of the available data, where the level of complexity is adjusted to fit the conditions of uncertainty...... separately: (1) Terrestrial nature; (2) Steams; (3) Ponds and lakes. GIS is used to combine data for agriculture praxis in terms of the crop distribution with distance to the nature elements. Pesticide application was estimated based on crop distribution and the toxicity for a series of toxic end...

  9. AN OVERVIEW OF MUTAGENIC POTENTIAL OF PESTICIDES

    Directory of Open Access Journals (Sweden)

    Aurel Popescu

    2013-12-01

    Full Text Available This paper presents a synthesis of mutagenic potential of a few pesticides. Cytotoxicity tests, using plant test systems in vivo, such as Allium cepa, are validated by the similar results performed in animal testing in vitro. Cytogenetic tests are usefulness for identifying and evaluating the damaging effects of pesticides present in various concentrations under different exposure times on living organisms. Mutagenic potential of different pesticides used can be detected cytologically by cellular inhibition (mitotic index and replication index are used as indicators of adequate cell proliferation, disruption in metaphase, induction of chromosomal aberrations, numerical and structural, ranging from chromosomal fragmentation to the disorganization of the mitotic spindle, and consequently of all subsequent dependent mitotic phases.

  10. Genetic Alterations in Pesticide Exposed Bolivian Farmers

    DEFF Research Database (Denmark)

    Jørs, Erik; González, Ana Rosa; Ascarrunz, Maria Eugenia

    2007-01-01

    : Questionnaires were applied and blood tests taken from 81 volunteers from La Paz County, of whom 48 were pesticide exposed farmers and 33 non-exposed controls. Sixty males and 21 females participated with a mean age of 37.3 years (range 17-76). Data of exposure and possible genetic damage were collected...... and evaluated by well known statistical methods, controlling for relevant confounders. To measure genetic damage chromosomal aberrations and the comet assay analysis were performed. Results: Pesticide exposed farmers had a higher degree of genetic damage compared to the control group. The number of chromosomal...... aberrations increased with the intensity of pesticide exposure. Females had a lower number of chromosomal aberrations than males, and people living at altitudes above 2500 metres seemed to exhibit more DNA damage measured by the comet assay. Conclusions: Bolivian farmers showed signs of genotoxic damage...

  11. Asymmetric Aminalization via Cation-Binding Catalysis

    DEFF Research Database (Denmark)

    Park, Sang Yeon; Liu, Yidong; Oh, Joong Suk

    2017-01-01

    Asymmetric cation-binding catalysis, in principle, can generate "chiral" anionic nucleophiles, where the counter cations are coordinated within chiral environments. Nitrogen-nucleophiles are intrinsically basic, therefore, its use as nucleophiles is often challenging and limiting the scope...... of the reaction. Particularly, a formation of configurationally labile aminal centers with alkyl substituents has been a formidable challenge due to the enamine/imine equilibrium of electrophilic substrates. Herein, we report enantioselective nucleophilic addition reactions of potassium phthalimides to Boc......-protected alkyl- and aryl-substituted α-amido sulfones. In-situ generated imines smoothly reacted with the nitrogen nucleophiles to corresponding aminals with good to excellent enantioselectivitiy under mild reaction conditions. In addition, transformation of aminal products gave biologically relevant...

  12. The adjuvant mechanism of cationic dimethyldioctadecylammonium liposomes

    DEFF Research Database (Denmark)

    Korsholm, Karen Smith; Agger, Else Marie; Foged, Camilla

    2007-01-01

    Cationic liposomes are being used increasingly as efficient adjuvants for subunit vaccines but their precise mechanism of action is still unknown. Here, we investigated the adjuvant mechanism of cationic liposomes based on the synthetic amphiphile dimethyldioctadecylammonium (DDA). The liposomes...... concentrations. This efficient adsorption onto the liposomes led to an enhanced uptake of OVA by BM-DCs as assessed by flow cytometry and confocal fluorescence laser-scanning microscopy. This was an active process, which was arrested at 4 degrees and by an inhibitor of actin-dependent endocytosis, cytochalasin D....... In vivo studies confirmed the observed effect because adsorption of OVA onto DDA liposomes enhanced the uptake of the antigen by peritoneal exudate cells after intraperitoneal injection. The liposomes targeted antigen preferentially to antigen-presenting cells because we only observed a minimal uptake...

  13. Suspected poisoning of domestic animals by pesticides.

    Science.gov (United States)

    Caloni, Francesca; Cortinovis, Cristina; Rivolta, Marina; Davanzo, Franca

    2016-01-01

    A retrospective study was carried out by reviewing all suspected cases of domestic animal poisoning attributed to pesticides, reported to the Milan Poison Control Centre (MPCC) between January 2011 and December 2013. During this period, pesticides were found to be responsible for 37.3% of all suspected poisoning enquiries received (815). The most commonly species involved was the dog (71.1% of calls) followed by the cat (15.8%), while a limited number of cases involved horses, goats and sheep. Most cases of exposure (47.1%) resulted in mild to moderate clinical signs. The outcome was reported in 59.9% of these cases, with death occurring in 10.4% of them. Insecticides (40.8%) proved to be the most common group of pesticides involved and exposure to pyrethrins-pyrethroids accounted for the majority of calls. According to the MPCC data, there has been a decrease in the number of suspected poisonings cases attributed to pesticides that have been banned by the EU, including aldicarb, carbofuran, endosulfan and paraquat. In contrast, there has been an increase of suspected poisoning cases attributed to the neonicotinoids, imidacloprid and acetamiprid, probably due to their widespread use in recent years. Cases of suspected poisoning that involved exposure to rodenticides accounted for 27.6% of calls received by the MPCC and anticoagulant rodenticides were the primary cause of calls, with many cases involving brodifacoum and bromadiolone. Herbicides were involved in 14.2% of calls related to pesticides and glyphosate was the main culprit in cases involving dogs, cats, horses, goats and sheep. As far as exposure to molluscicides (11.5%) and fungicides (5.9%), most of the cases involved dogs and the suspected poisoning agents were metaldehyde and copper compounds respectively. The data collected are useful in determining trends in poisoning episodes and identifying newly emerging toxicants, thus demonstrating the prevalence of pesticides as causative agents in animal

  14. Pesticides and respiratory symptoms among farmers

    Directory of Open Access Journals (Sweden)

    Faria Neice Müller Xavier

    2005-01-01

    Full Text Available OBJECTIVE: Despite the intensive use of pesticides in agriculture there are few studies assessing the risk of respiratory conditions from this exposure. The study aimed at quantifying the prevalence of respiratory symptoms among farmers and evaluating its relationship with occupational use of pesticides and the prevalence of respiratory symptoms. METHODS: A cross-sectional study was conducted among 1,379 farmers from two municipalities of Southern Brazil in 1996. Frequency and type of chemical exposure and pesticide poisoning were recorded for both sexes. All subjects aged 15 years or older with at least 15 weekly hours of agricultural activity were interviewed. An adapted questionnaire developed by the American Thoracic Society was used for the assessment of respiratory symptoms. Multivariate logistic regression analysis was carried out. RESULTS: More than half (55% of interviewees were male. The prevalence of asthma symptoms was 12% and chronic respiratory disease symptoms was 22%. Higher odds ratios for both asthma (OR=1.51; 95% CI: 1.07-2.14 and chronic respiratory disease (OR=1.34; 95% CI 1.00-1.81 symptoms were found in women. Logistic regression analysis identified associations between many forms of exposure to pesticides and increased respiratory symptoms. Occurrence of pesticide poisoning was associated with higher prevalence of asthma symptoms (OR=1.54; 95% CI: 1.04-2.58 and chronic respiratory disease symptoms (OR=1.57; 95% CI: 1.08-2.28. CONCLUSIONS: In spite of causality limitations, the study results provide evidence that farming exposure to pesticides is associated with higher prevalence of respiratory symptoms, especially when the exposure is above two days per month.

  15. Cation Permeability in Soybean Aleurone Layer

    OpenAIRE

    Noda, Hiroko; Fukuda, Mitsuru

    1998-01-01

    The permeation of water and ions into bean seeds is essential for processing and cooking of beans. The permeability of cations, K, Na, Ca, and Mg ions, into soybean seed tissue, especially aleurone layer, during water uptake was investigated to characterize the ion permeation into soybeans. Aleurone layers and seed coats contained relatively high concentration of endogenous K and Ca ions, and endogenous Ca ion, respectively. The amounts of Ca ion entered seed coats and aleurone layers were gr...

  16. Regulation of Cation Balance in Saccharomyces cerevisiae

    Science.gov (United States)

    Cyert, Martha S.; Philpott, Caroline C.

    2013-01-01

    All living organisms require nutrient minerals for growth and have developed mechanisms to acquire, utilize, and store nutrient minerals effectively. In the aqueous cellular environment, these elements exist as charged ions that, together with protons and hydroxide ions, facilitate biochemical reactions and establish the electrochemical gradients across membranes that drive cellular processes such as transport and ATP synthesis. Metal ions serve as essential enzyme cofactors and perform both structural and signaling roles within cells. However, because these ions can also be toxic, cells have developed sophisticated homeostatic mechanisms to regulate their levels and avoid toxicity. Studies in Saccharomyces cerevisiae have characterized many of the gene products and processes responsible for acquiring, utilizing, storing, and regulating levels of these ions. Findings in this model organism have often allowed the corresponding machinery in humans to be identified and have provided insights into diseases that result from defects in ion homeostasis. This review summarizes our current understanding of how cation balance is achieved and modulated in baker’s yeast. Control of intracellular pH is discussed, as well as uptake, storage, and efflux mechanisms for the alkali metal cations, Na+ and K+, the divalent cations, Ca2+ and Mg2+, and the trace metal ions, Fe2+, Zn2+, Cu2+, and Mn2+. Signal transduction pathways that are regulated by pH and Ca2+ are reviewed, as well as the mechanisms that allow cells to maintain appropriate intracellular cation concentrations when challenged by extreme conditions, i.e., either limited availability or toxic levels in the environment. PMID:23463800

  17. Applicability and modelling of nanofiltration and reverse osmosis for remediation of groundwater polluted with pesticides and pesticide transformation products

    DEFF Research Database (Denmark)

    Madsen, Henrik Tækker; Søgaard, Erik Gydesen

    2014-01-01

    The main body of research on pesticide removal with membranes has looked at pesticides used for pest control, but during transport from surface to groundwater aquifers, pesticides are transformed. Therefore the real polluting compounds are often transformation products, and this vastly increases ...

  18. Pesticide use and self-reported symptoms of acute pesticide poisoning among aquatic farmers in Phnom Penh, Cambodia

    DEFF Research Database (Denmark)

    Jensen, Hanne Klith; Konradsen, Flemming; Jørs, Erik

    2011-01-01

    Organophosphates and carbamates (OPs/CMs) are known for their acetylcholinesterase inhibiting character. A cross-sectional study of pesticide handling practices and self-perceived symptoms of acute pesticide poisoning was conducted using questionnaire-based interviews with 89 pesticide sprayers...

  19. Controlling chemistry with cations: photochemistry within zeolites.

    Science.gov (United States)

    Ramamurthy, V; Shailaja, J; Kaanumalle, Lakshmi S; Sunoj, R B; Chandrasekhar, J

    2003-08-21

    The alkali ions present in the supercages of zeolites X and Y interact with included guest molecules through quadrupolar (cation-pi), and dipolar (cation-carbonyl) interactions. The presence of such interactions can be inferred through solid-state NMR spectra of the guest molecules. Alkali ions, as illustrated in this article, can be exploited to control the photochemical and photophysical behaviors of the guest molecules. For example, molecules that rarely phosphoresce can be induced to do so within heavy cation-exchanged zeolites. The nature (electronic configuration) of the lowest triplet state of carbonyl compounds can be altered with the help of light alkali metal ions. This state switch (n pi*-pi pi*) helps to bring out reactivity that normally remains dormant. Selectivity obtained during the singlet oxygen oxidation of olefins within zeolites illustrates the remarkable control that can be exerted on photoreactions with the help of a confined medium that also has active sites. The reaction cavities of zeolites, like enzymes, are not only well-defined and confined, but also have active sites that closely guide the reactant molecule from start to finish. The examples provided here illustrate that zeolites are far more useful than simple shape-selective catalysts.

  20. Limited data speaker identification

    Indian Academy of Sciences (India)

    H S Jayanna; S R Mahadeva Prasanna

    2010-10-01

    In this paper, the task of identifying the speaker using limited training and testing data is addressed. Speaker identification system is viewed as four stages namely, analysis, feature extraction, modelling and testing. The speaker identification performance depends on the techniques employed in these stages. As demonstrated by different experiments, in case of limited training and testing data condition, owing to less data, existing techniques in each stage will not provide good performance. This work demonstrates the following: multiple frame size and rate (MFSR) analysis provides improvement in the analysis stage, combination of mel frequency cepstral coefficients (MFCC), its temporal derivatives $(\\Delta,\\Delta \\Delta)$, linear prediction residual (LPR) and linear prediction residual phase (LPRP) features provides improvement in the feature extraction stage and combination of learning vector quantization (LVQ) and gaussian mixture model – universal background model (GMM–UBM) provides improvement in the modelling stage. The performance is further improved by integrating the proposed techniques at the respective stages and combining the evidences from them at the testing stage. To achieve this, we propose strength voting (SV), weighted borda count (WBC) and supporting systems (SS) as combining methods at the abstract, rank and measurement levels, respectively. Finally, the proposed hierarchical combination (HC) method integrating these three methods provides significant improvement in the performance. Based on these explorations, this work proposes a scheme for speaker identification under limited training and testing data.

  1. PESTLCI – A PESTICIDE DISTRIBUTION MODEL FOR LCA

    DEFF Research Database (Denmark)

    Birkved, Morten; Hauschild, Michael Zwicky

    and assessment of pesticide applications. The report therefore starts with a review of the work reported by the CAPER project as described in / / in order to locate new methods amenable for: 1. Handling of pesticide screening in LCA 2. Distribution modelling of pesticides in LCA 3. Evaluation of human exposure...... in LCA Following the review of existing methods, a number of modifications and new modules are developed and integrated into the existing method for pesticide distribution modelling to arrive at PESTLCI. Finally, PESTLCI is tested on three pesticide applications and the results compared to the results...

  2. Kinetic Modelling of Pesticidal Degradation and Microbial Growth in Soil

    Institute of Scientific and Technical Information of China (English)

    LIUDUO-SEN; WANGZONG-SHENG; 等

    1994-01-01

    This paper discusses such models for the degradation kinetics of pesticides in soil as the model expressing the degradation rate as a function of two varables:the pesticide concentration and the number of pesticide degrading microorganisms,the model expressing the pesticide concentration as explicit or implicit function of time ,and the model exprssing the pesticide loss rate constants as functions of temperature,These models may interpret the degradation curves with an inflection point.A Kinetic model describing the growth processes of microbial populations in a closed system is reported as well.

  3. Pesticide Exposure, Safety Issues, and Risk Assessment Indicators

    Directory of Open Access Journals (Sweden)

    Christos A. Damalas

    2011-05-01

    Full Text Available Pesticides are widely used in agricultural production to prevent or control pests, diseases, weeds, and other plant pathogens in an effort to reduce or eliminate yield losses and maintain high product quality. Although pesticides are developed through very strict regulation processes to function with reasonable certainty and minimal impact on human health and the environment, serious concerns have been raised about health risks resulting from occupational exposure and from residues in food and drinking water. Occupational exposure to pesticides often occurs in the case of agricultural workers in open fields and greenhouses, workers in the pesticide industry, and exterminators of house pests. Exposure of the general population to pesticides occurs primarily through eating food and drinking water contaminated with pesticide residues, whereas substantial exposure can also occur in or around the home. Regarding the adverse effects on the environment (water, soil and air contamination from leaching, runoff, and spray drift, as well as the detrimental effects on wildlife, fish, plants, and other non-target organisms, many of these effects depend on the toxicity of the pesticide, the measures taken during its application, the dosage applied, the adsorption on soil colloids, the weather conditions prevailing after application, and how long the pesticide persists in the environment. Therefore, the risk assessment of the impact of pesticides either on human health or on the environment is not an easy and particularly accurate process because of differences in the periods and levels of exposure, the types of pesticides used (regarding toxicity and persistence, and the environmental characteristics of the areas where pesticides are usually applied. Also, the number of the criteria used and the method of their implementation to assess the adverse effects of pesticides on human health could affect risk assessment and would possibly affect the characterization

  4. Alkali cation specific adsorption onto fcc(111) transition metal electrodes.

    Science.gov (United States)

    Mills, J N; McCrum, I T; Janik, M J

    2014-07-21

    The presence of alkali cations in electrolyte solutions is known to impact the rate of electrocatalytic reactions, though the mechanism of such impact is not conclusively determined. We use density functional theory (DFT) to examine the specific adsorption of alkali cations to fcc(111) electrode surfaces, as specific adsorption may block catalyst sites or otherwise impact surface catalytic chemistry. Solvation of the cation-metal surface structure was investigated using explicit water models. Computed equilibrium potentials for alkali cation adsorption suggest that alkali and alkaline earth cations will specifically adsorb onto Pt(111) and Pd(111) surfaces in the potential range of hydrogen oxidation and hydrogen evolution catalysis in alkaline solutions.

  5. Disposal and degradation of pesticide waste.

    Science.gov (United States)

    Felsot, Allan S; Racke, Kenneth D; Hamilton, Denis J

    2003-01-01

    Generation of pesticide waste is inevitable during every agricultural operation from storage to use and equipment cleanup. Large-scale pesticide manufacturers can afford sophisticated recovery, treatment, and cleanup techniques. Small-scale pesticide users, for example, single farms or small application businesses, struggle with both past waste problems, including contaminated soils, and disposal of unused product and equipment rinsewater. Many of these problems have arisen as a result of inability to properly handle spills during, equipment loading and rinsewater generated after application. Small-scale facilities also face continued problems of wastewater handling. Old, obsolete pesticide stocks are a vexing problem in numerous developing countries. Pesticide waste is characterized by high concentrations of a diversity of chemicals and associated adjuvants. Dissipation of chemicals at elevated concentrations is much slower than at lower concentrations, in part because of microbial toxicity and mass transfer limitations. High concentrations of pesticides may also move faster to lower soil depths, especially when pore water becomes saturated wish a compound. Thus, if pesticide waste is not properly disposed of, groundwater and surface water contamination become probable. The Waste Management Hierarchy developed as an Australian Code of Practice can serve as a guide for development of a sound waste management plan. In order of desirability, the course of actions include waste avoidance, waste reduction, waste recycling, waste treatment, and waste disposal. Proper management of pesticide stocks, including adequate storage conditions, good inventory practices, and regular turnover of products,. will contribute to waste avoidance and reduction over the long-term. Farmers can also choose to use registered materials that have the lowest recommended application rates or are applied in the least volume of water. Wastewater that is generated during equipment rinsing can be

  6. [Antioxidant activity of cationic whey protein isolate].

    Science.gov (United States)

    titova, M E; Komolov, S A; Tikhomirova, N A

    2012-01-01

    The process of lipid peroxidation (LPO) in biological membranes of cells is carried out by free radical mechanism, a feature of which is the interaction of radicals with other molecules. In this work we investigated the antioxidant activity of cationic whey protein isolate, obtained by the cation-exchange chromatography on KM-cellulose from raw cow's milk, in vitro and in vivo. In biological liquids, which are milk, blood serum, fetal fluids, contains a complex of biologically active substances with a unique multifunctional properties, and which are carrying out a protective, antimicrobial, regenerating, antioxidant, immunomodulatory, regulatory and others functions. Contents of the isolate were determined electrophoretically and by its biological activity. Cationic whey protein isolate included lactoperoxidase, lactoferrin, pancreatic RNase, lysozyme and angeogenin. The given isolate significantly has an antioxidant effect in model experimental systems in vitro and therefore may be considered as a factor that can adjust the intensity of lipid oxidation. In model solutions products of lipid oxidation were obtained by oxidation of phosphatidylcholine by hydrogen peroxide in the presence of a source of iron. The composition of the reaction mixture: 0,4 mM H2O2; 50 mcM of hemin; 2 mg/ml L-alpha-phosphatidylcholine from soybean (Sigma, German). Lipid peroxidation products were formed during the incubation of the reaction mixture for two hours at 37 degrees C. In our studies rats in the adaptation period immediately after isolation from the nest obtained from food given orally native cationic whey protein isolate at the concentration three times higher than in fresh cow's milk. On the manifestation of the antioxidant activity of cationic whey protein isolate in vivo evidence decrease of lipid peroxidation products concentration in the blood of rats from the experimental group receipt whey protein isolate in dos 0,6 mg/g for more than 20% (pwhey protein isolate has an

  7. Cell volume-regulated cation channels.

    Science.gov (United States)

    Wehner, Frank

    2006-01-01

    Considering the enormous turnover rates of ion channels when compared to carriers it is quite obvious that channel-mediated ion transport may serve as a rapid and efficient mechanism of cell volume regulation. Whenever studied in a quantitative fashion the hypertonic activation of non-selective cation channels is found to be the main mechanism of regulatory volume increase (RVI). Some channels are inhibited by amiloride (and may be related to the ENaC), others are blocked by Gd(3) and flufenamate (and possibly linked to the group of transient receptor potential (TRP) channels). Nevertheless, the actual architecture of hypertonicity-induced cation channels remains to be defined. In some preparations, hypertonic stress decreases K(+) channel activity so reducing the continuous K(+) leak out of the cell; this is equivalent to a net gain of cell osmolytes facilitating RVI. The hypotonic activation of K(+) selective channels appears to be one of the most common principles of regulatory volume decrease (RVD) and, in most instances, the actual channels involved could be identified on the molecular level. These are BKCa (or maxi K(+)) channels, IK(Ca) and SK(Ca) channels (of intermediate and small conductance, respectively), the group of voltage-gated (Kv) channels including their Beta (or Kv ancilliary) subunits, two-pore K(2P) channels, as well as inwardly rectifying K(+) (Kir) channels (also contributing to K(ATP) channels). In some cells, hypotonicity activates non-selective cation channels. This is surprising, at first sight, because of the inside negative membrane voltage and the sum of driving forces for Na(+) and K(+) diffusion across the cell membrane rather favouring net cation uptake. Some of these channels, however, exhibit a P(K)/P(Na) significantly higher than 1, whereas others are Ca(++) permeable linking hypotonic stress to the activation of Ca(++) dependent ion channels. In particular, the latter holds for the group of TRPs which are specialised in the

  8. Influence of different disease control pesticide strategies on multiple pesticide residue levels in apple

    DEFF Research Database (Denmark)

    Poulsen, Mette Erecius; Naef, A.; Gasser, S.;

    2009-01-01

    % of European Maximum Residue Levels (EU MRL) and that the number of residues present at levels above 0.01 mg kg(-1) should be limited to a maximum of four. The strategies fulfilled the requirement to use combinations of different active substances in order to prevent the emergence of resistance to pesticides......Seven pesticide application strategies were investigated to control apple scab (Venturia inaequalis) and powdery mildew (Podosphaera leucotricha) and, at the same time.. fulfil the new quality standards implemented by some German retailers. These demand that pesticide residues should be below 80....... The trials were conducted at two sites in Switzerland, in 2007, and all strategies and applications were in accordance with actual practice. Four replicates of apple samples from each strategy were then analysed for pesticide residues. The incidence of infection with apple scab and powdery mildew were...

  9. Pesticide exposure and end-stage renal disease risk among wives of pesticide applicators in the Agricultural Health Study✩

    Science.gov (United States)

    Lebov, Jill F.; Engel, Lawrence S.; Richardson, David; Hogan, Susan L.; Sandler, Dale P.; Hoppin, Jane A.

    2015-01-01

    Background Pesticide exposure has been found to cause renal damage and dysfunction in experimental studies, but epidemiological research on the renal effects of chronic low-level pesticide exposure is limited. We investigated the relationships between end-stage renal disease (ESRD) among wives of licensed pesticide applicators (N = 31,142) in the Agricultural Health Study (AHS) and (1) personal pesticide use, (2) exposure to the husband's pesticide use, and (3) other pesticide-associated farming and household activities. Methods AHS participants reported pesticide exposure via self-administered questionnaires at enrollment (1993–1997). ESRD cases were identified via linkage to the United States Renal Data System. Associations between ESRD and pesticide exposures were estimated with Cox proportional hazard regression models controlling for age at enrollment. Models of associations with farming and household factors were additionally adjusted for personal use of pesticides. Results We identified 98 ESRD cases diagnosed between enrollment and 31 December 2011. Although women who ever applied pesticides (56% of cohort) were less likely than those who did not apply to develop ESRD (Hazard Ratio (HR): 0.42; 95% CI: 0.28, 0.64), among women who did apply pesticides, the rate of ESRD was significantly elevated among those who reported the highest (vs. lowest) cumulative general pesticide use (HR: 4.22; 95% CI: 1.26, 14.20). Among wives who never applied pesticides, ESRD was associated with husbands' ever use of paraquat (HR = 1.99; 95% CI: 1.14, 3.47) and butylate (HR = 1.71; 95% CI: 1.00, 2.95), with a positive exposure–response pattern for husband’s cumulative use of these pesticides. Conclusions ESRD may be associated with direct and/or indirect exposure to pesticides among farm women. Future studies should evaluate indirect exposure risk among other rural populations. PMID:26505650

  10. Removal of pesticides from white and red wines by microfiltration.

    Science.gov (United States)

    Doulia, Danae S; Anagnos, Efstathios K; Liapis, Konstantinos S; Klimentzos, Demetrios A

    2016-11-05

    The aim of this work is the investigation of microfiltration in removing pesticides from a white and a red Greek wine. Six membranes with pore size 0.45μm were investigated. Two mixtures of 23 and 9 pesticides, and single pesticide solutions were added in the wine. The pesticides tested belong to 11 chemical groups. Solid phase extraction (SPE) followed by gas chromatography (GC) with electron capture detector (ECD) were performed to analyze pesticide residues of the filtered fortified wine. Distinct behavior was exhibited by each membrane. Cellulose acetate and cellulose nitrate showed higher mean pesticide removal for both wines, followed by polyethersulfone, regenerated cellulose, and polyamides. The filtration effectiveness was correlated to the membrane type and to the pesticide chemical structure and properties (octanol-water partition coefficient, water solubility) and compared for the wines tested. In most cases, the more hydrophobic pesticides (pyrethroids and aldrin) showed higher removal from red wine than white wine. Adsorption on membranes was increased by increasing hydrophobicity and decreasing hydrophilicity of organic pesticide molecule. The removal of each pesticide from its single solution was generally higher than that from its mixtures, allowing the estimation of the antagonistic and synergistic effects of pesticides in the mixtures.

  11. Agricultural Pesticide Management in Thailand: Situation and Population Health Risk.

    Science.gov (United States)

    Panuwet, Parinya; Siriwong, Wattasit; Prapamontol, Tippawan; Ryan, P Barry; Fiedler, Nancy; Robson, Mark G; Barr, Dana Boyd

    2012-03-01

    As an agricultural country and one of the world's major food exporters, Thailand relies heavily on the use of pesticides to protect crops and increase yields. During the past decade, the Kingdom of Thailand has experienced an approximate four-fold increase in pesticide use. This increase presents a challenge for the Royal Thai Government in effectively managing and controlling pesticide use based upon the current policies and legal infrastructure. We have reviewed several key components for managing agricultural pesticides in Thailand. One of the main obstacles to effective pesticide regulation in Thailand is the lack of a consolidated, uniform system designed specifically for pesticide management. This deficit has weakened the enforcement of existing regulations, resulting in misuse/overuse of pesticides, and consequently, increased environmental contamination and human exposure. This article provides a systematic review of how agricultural pesticides are regulated in Thailand. In addition, we provide our perspectives on the current state of pesticide management, the potential health effects of widespread, largely uncontrolled use of pesticides on the Thai people and ways to improve pesticide management in Thailand.

  12. Assessing pesticide exposure of the aquatic environment in tropical catchments

    Science.gov (United States)

    Weiss, Frederik; Zurbrügg, Christian; Eggen, Rik; Castillo, Luisa; Ruepert, Clemens; Stamm, Christian

    2015-04-01

    Today, pesticides are intensively used in agriculture across the globe. Worldwide about 2.4×106 tons of pesticides are used annually on 1.6×109 ha of arable land. This yields a global average use of pesticides of 1.53 kg ha-1 year-1. Available data suggest that the use in the agricultural sector will continue to grow. Recently it was estimated that within the last decade, the world pesticide market increased by 93% and the Brazilian market alone by 190%. Though pesticides are intensively used in many low and middle income countries (LAMICs), scientifically sound data of amounts and types of pesticide use and the resulting impact on water quality are lacking in many of these countries. Therefore it is highly relevant to: i) identify risk areas where pesticides affect environmental health, ii) understand the environmental behavior of pesticides in vulnerable tropical ecosystems; and iii) develop possible mitigation options to reduce their exposure to ecosystems and humans. Here we present a project that will focus on assessing pesticide exposure of the aquatic environment and humans in tropical catchments of LAMICs. A catchment in the Zarcero province in Costa Rica will be the test case. Pesticide exposure will be assessed by passive sampling. In order to cover a broad range of compounds of possible use, two sampling devices will be used: SDB membranes for collecting polar compounds and silicon sheets for accumulating apolar pesticides. Extracts will be subsequently analysed by GC-MSMS and LC-HRMS.

  13. PESTLCI – A PESTICIDE DISTRIBUTION MODEL FOR LCA

    DEFF Research Database (Denmark)

    Birkved, Morten; Hauschild, Michael Zwicky

    and assessment of pesticide applications. The report therefore starts with a review of the work reported by the CAPER project as described in / / in order to locate new methods amenable for: 1. Handling of pesticide screening in LCA 2. Distribution modelling of pesticides in LCA 3. Evaluation of human exposure......The aim of the presented work is to develop a model for distribution of pesticides into the environment following application to the field. Based on input of required substance characteristics and applied quantities for the pesticides, the model will estimate the emissions to the air, water, soil...... in LCA Following the review of existing methods, a number of modifications and new modules are developed and integrated into the existing method for pesticide distribution modelling to arrive at PESTLCI. Finally, PESTLCI is tested on three pesticide applications and the results compared to the results...

  14. How to minimise direct pesticide load on bees

    DEFF Research Database (Denmark)

    Ørum, Jens Erik; Navntoft, Søren

    Monitoring, warning and decision support systems (MWD systems) may be profitable solutions to crop protection problems, and at the same time they may reduce the use of pesticides and the pesticide load on human health, non-target organisms and ground water resources. This presentation describes...... a simple method to pinpoint pesticide problems that causes the highest regional pesticide load (regional hot spots) to various non-target organisms. Finally the potential of MWD systems to reduce the pesticide load in these regional hotspots are discussed with a special focus on bees and other insects....... The regional pesticide load is calculated by using the national Danish sales statistic for pesticides in combination with the EU Foot Print database and detailed GIS data for each crop and fields throughout the country. A number of serious hotspots have been identified, in most cases in regions with a high...

  15. Pesticide contamination of Tenebrio molitor (Coleoptera: Tenebrionidae) for human consumption.

    Science.gov (United States)

    Houbraken, Michael; Spranghers, Thomas; De Clercq, Patrick; Cooreman-Algoed, Margot; Couchement, Tasmien; De Clercq, Griet; Verbeke, Sarah; Spanoghe, Pieter

    2016-06-15

    The use of pesticides contributes to the productivity and the quality of the cultivated crop. A large portion of the agricultural produce is not consumed as it is not an edible part or the quality of the product is too low. This waste of agricultural produce can be valorised as a substrate for the production of certain insects for human consumption. However, pesticides applied on the plants might accumulate during the life cycle of the insects fed on the waste materials and may cause a health risk to humans consuming the insects. Pesticide residues in larvae of the yellow mealworm, Tenebrio molitor, were investigated. We monitored the accumulation of pesticides in the larvae upon consumption of contaminated fresh produce. An increased uptake rate by the insects was found for pesticides with higher Kow-values. Excretion of pesticides by the insect was inversely related to the log(Kow) values of the pesticides.

  16. Photocatalytic degradation of pesticides by titanium dioxide and titanium pillared purified clays

    Directory of Open Access Journals (Sweden)

    M. Abdennouri

    2016-09-01

    Full Text Available Titanium dioxide was synthesized by the sol–gel method and titanium pillared purified clay was prepared with two titanium contents: 1.15 and 10.5 mmol of Ti per gram of clay. The composites were synthesized by immobilizing TiO2 onto surfactant-pillared clay via ion exchange reaction between clay with cation surfactant, cetyl-trimethyl ammonium bromide (CTMABr. The composition and texture of the prepared photocatalysts were characterized with X-ray powder diffraction (XRD, FT-IR spectroscopy, transmission electron microscopy (TEM and energy-dispersive spectroscopy (EDX. The adsorption performance and photocatalytic activities of the prepared samples were investigated using 2,4-dichlorophenoxyacetic acid (2,4-D and 2,4-dichlorophenoxypropionic acid (2,4-DP as models of organic pollutants. The results were obtained that these photocatalysts can effectively degrade selected pesticides. The removal efficiency increases with the Ti content in the pillared clay.

  17. The role of private pesticide vendors in preventing access to pesticides for self-poisoning in rural Sri Lanka

    DEFF Research Database (Denmark)

    Weerasinghe, Manjula; Pearson, Melissa; Peiris, Ravi;

    2014-01-01

    In 15% to 20% of self-poisoning cases, the pesticides used are purchased from shops just prior to ingestion. We explored how pesticide vendors interacted with customers at risk of self-poisoning to identify interventions to prevent such poisonings. Two strategies were specifically discussed......: selling pesticides only to farmers bearing identity cards or customers bearing pesticide 'prescriptions'. Vendors reported refusing to sell pesticides to people thought to be at risk of self-poisoning, but acknowledged the difficulty of distinguishing them from legitimate customers; vendors also stated...

  18. 75 FR 17571 - Pendimethalin; Pesticide Tolerances

    Science.gov (United States)

    2010-04-07

    ... pendimethalin and its metabolite, expressed as pendimethalin equivalents, in or on alfalfa forage. BASF... not limited to those engaged in the following activities: Crop production (NAICS code 111). Animal production (NAICS code 112). Food manufacturing (NAICS code 311). Pesticide manufacturing (NAICS code 32532...

  19. 76 FR 27268 - Glyphosate; Pesticide Tolerance

    Science.gov (United States)

    2011-05-11

    ... AGENCY 40 CFR Part 180 Glyphosate; Pesticide Tolerance AGENCY: Environmental Protection Agency (EPA... glyphosate in or on corn, field, forage. Monsanto Company requested this tolerance under the Federal Food... tolerance for residues of the herbicide glyphosate, N-(phosphonomethyl) glycine, in or on corn, field...

  20. Commercial Pesticides Applicator Manual: Public Health.

    Science.gov (United States)

    Fitzwater, William D.; Reed, Leonard G., Jr.

    This training manual provides information needed to meet the minimum EPA standards for certification as a commercial applicator of pesticides in the public health pest control category. The text discusses pests such as roaches, bedbugs, bees, mosquitoes, gnats, flies, and rodents with possible control measures provided. (CS)

  1. Governing pesticide in vegetable production in Vietnam

    NARCIS (Netherlands)

    Hoi, Van P.

    2010-01-01

    The economic liberalization in Vietnam, initiated in the middle of the 1980s, contributed to the further intensification and expansion of private actor-engagement in agriculture and food-supply. Vietnamese farmers, who already considered applying pesticides the most effective manner to protect their

  2. 77 FR 49732 - Cyprodinil; Pesticide Tolerances

    Science.gov (United States)

    2012-08-17

    ... reduced responsiveness to sensory stimuli were observed and disappeared in all animals by day 3 to 4. The... posed by human exposure to the pesticide. For hazards that have a threshold below which there is no... (PAD) or a reference dose (RfD)--and a safe margin of exposure (MOE). For non-threshold risks, the...

  3. Utilization of poultry litter for pesticide bioremediation

    Science.gov (United States)

    Agricultural chemical products such as pesticides have been used to increase crop production, especially in undeveloped countries. Poultry litter, the combination of feces and bedding materials, has also been used as an alternative to improve soil quality for crop production. However, information re...

  4. 76 FR 34877 - Difenoconazole; Pesticide Tolerances

    Science.gov (United States)

    2011-06-15

    .../parental animals. In the prenatal developmental toxicity study in rats, maternal toxicity was manifested as... parental systemic and off spring toxicity NOAEL was 1.25 mg/kg/day. ] 3. Conclusion. EPA has determined... Pesticide Programs. Therefore, 40 CFR chapter I is amended as follows: PART 180-- 0 1. The authority...

  5. 77 FR 59558 - Sulfentrazone; Pesticide Tolerances

    Science.gov (United States)

    2012-09-28

    ... is not intended to be exhaustive, but rather provides a guide to help readers determine whether this... filing of a pesticide petition (PP 2E8020) by IR-4, 500 College Road East, Suite 201W., Princeton, NJ... provided the appropriate residue field trial data to support a tolerance on this group. EPA...

  6. 78 FR 75262 - Flonicamid; Pesticide Tolerances

    Science.gov (United States)

    2013-12-11

    ... intended to be exhaustive, but rather provides a guide to help readers determine whether this document... of a pesticide petition (PP 2E8137) by IR-4, 500 College Rd. East, Suite 201W., Princeton, NJ 08540.... For alfalfa forage, the tolerance was calculated using 5x the mean of the field trial data instead...

  7. 77 FR 63745 - Buprofezin; Pesticide Tolerances

    Science.gov (United States)

    2012-10-17

    ... rather to provide a guide for readers regarding entities likely to be affected by this action. Other...), 500 College Road East, Suite 201 W, Princeton, NJ 08540, and PP 1F7905 by Nichino America, Inc., 4550... levels from field trial data, average residue levels from USDA Pesticide Data Program (PDP) data,...

  8. 78 FR 69562 - Fenpropathrin; Pesticide Tolerances

    Science.gov (United States)

    2013-11-20

    ..., but rather provides a guide to help readers determine whether this document applies to them... College Rd. East, Suite 201W., Princeton, NJ 08540. The petition requested that 40 CFR 180.466 be amended... residues, distributions of field trial values, and distributions of Pesticide Data Program (PDP)...

  9. 75 FR 53586 - Bifenazate; Pesticide Tolerances

    Science.gov (United States)

    2010-09-01

    ... code 32532). This listing is not intended to be exhaustive, but rather to provide a guide for readers... (PP 9E7642) by Interregional Research Project 4 (IR-4), 500 College Road East, Suite 201W, Princeton... using the Guidance for Setting Pesticide Tolerances Based on Field Trial Data SOP to determine...

  10. 77 FR 40806 - Methoxyfenozide; Pesticide Tolerances

    Science.gov (United States)

    2012-07-11

    ... intended to be exhaustive, but rather to provide a guide for readers regarding entities likely to be... pesticide petition (PP 1E7842) by IR-4, 500 College Road East, Suite 201W, Princeton, NJ 08540. The petition... citrus oils. However, because residues from the citrus field trials are similar enough to warrant a...

  11. 75 FR 26662 - Fluazinam; Pesticide Tolerances

    Science.gov (United States)

    2010-05-12

    ...). This listing is not intended to be exhaustive, but rather to provide a guide for readers regarding... filing of a pesticide petition (PP 8E7506) by IR-4, 500 College Road East, Suite 201 W, Princeton, NJ... commodities except apple (for which the average field trial residue value was used) and assumed 100 PCT...

  12. Mapping Pesticide Partition Coefficients By Electromagnetic Induction

    Science.gov (United States)

    A potential method for reducing pesticide leaching is to base application rates on the leaching potential of a specific chemical and soil combination. However, leaching is determined in part by the partitioning of the chemical between the soil and soil solution, which varies across a field. Standard...

  13. 78 FR 29041 - Sulfoxaflor; Pesticide Tolerances

    Science.gov (United States)

    2013-05-17

    ... pesticide manufacturer. The following list of North American Industrial Classification System (NAICS) codes... member of a new class of insecticides, the sulfoximines, and is a highly efficacious activator of the... and mice indicate that sulfoxaflor is an activator of the mammalian nAChR as well, but to a...

  14. 78 FR 60707 - Glyphosate; Pesticide Tolerances

    Science.gov (United States)

    2013-10-02

    ... AGENCY 40 CFR Part 180 Glyphosate; Pesticide Tolerances AGENCY: Environmental Protection Agency (EPA... herbicide glyphosate in or on canola, seed at 20 parts per million (ppm) by changing the tolerance expression from the combined residues of glyphosate only, to the combined residues of glyphosate and...

  15. Governing pesticide in vegetable production in Vietnam

    NARCIS (Netherlands)

    Hoi, Van P.

    2010-01-01

    The economic liberalization in Vietnam, initiated in the middle of the 1980s, contributed to the further intensification and expansion of private actor-engagement in agriculture and food-supply. Vietnamese farmers, who already considered applying pesticides the most effective manner to protect their

  16. Monitoring of pesticide residues in vegetarian diet.

    Science.gov (United States)

    Kumari, Beena; Kathpal, T S

    2009-04-01

    Samples (28) of complete vegetarian diet consumed from morning till night i.e. tea, milk, breakfast, lunch, snacks, dinner, sweet dish etc. were collected from homes, hostels and hotels periodically from Hisar and analysed for detecting the residues of organochlorine, synthetic pyrethriod, organophosphate and carbamate insecticides. The estimation was carried out by using multi-residue analytical technique employing gas chromatograph (GC)-electron capture detector and GC-nitrogen phosphorous detector systems equipped with capillary columns. The whole diet sample was macerated in a mixer grinder and a representative sample in duplicate was analyzed for residues keeping the average daily diet of an adult to be 1,300 g. On comparing the data, it was found that actual daily intake (microgram/person/day) of lindane in two and endosulfan in four samples exceeded the acceptable daily intake. Residues of other pesticides in all the diet samples were lower than the acceptable daily intake (ADI) of the respective pesticides. The study concluded that although all the diet samples were found contaminated with one or the other pesticide, the actual daily intake of only a few pesticides was higher than their respective ADI. More extensive study covering other localities of Haryana has been suggested to know the overall scenario of contamination of vegetarian diet.

  17. Diagnosis & Treatment of Poisoning by Pesticides.

    Science.gov (United States)

    Environmental Protection Agency, Washington, DC. Office of Pesticide Programs.

    This report succinctly discusses the steps necessary to diagnose and treat poisoning from pesticides, especially organophosphates, carbamates and chlorinated hydrocarbons. Immediate and continuing steps in the care of poisoning victims are outlined with supportive information on where to locate emergency assistance. (CS)

  18. A greenhouse without pesticides : fact or fantasy ?

    NARCIS (Netherlands)

    Lenteren, van J.C.

    2000-01-01

    Crop protection in European greenhouses became strongly chemically oriented shortly after the Second World War in the 1950s. But an excellent climate for fast reproduction of pests and diseases demanded high spray frequencies and, thus, resulted in quick development of resistance against pesticides.

  19. Environmental risk assessment of pesticides in Ethiopia

    NARCIS (Netherlands)

    Teklu, B.M.

    2016-01-01

    The current increase in application rate and usage frequency of application of pesticides in Ethiopia pose direct risks to surface water aquatic organisms and humans and cattle using surface water as a source of drinking water in rural parts of the country. A model based risk assessment as currently

  20. 77 FR 73940 - Flubendiamide; Pesticide Tolerances

    Science.gov (United States)

    2012-12-12

    ... to the pesticide chemical residue, including all anticipated dietary exposures and all other... sensitizer under the conditions of the guinea pig maximization test. In the mammalian toxicology database..., PAD, LOC for Study and toxicological effects safety factors risk assessment Acute Dietary (Females,...

  1. Pesticide mitigation capacities of constructed wetlands

    Science.gov (United States)

    Matthew T. Moore; Charles M. Cooper; Sammie Smith; John H. Rodgers

    2000-01-01

    This research focused on using constructed wetlands along field perimeters to buffer receiving water against potential effects of pesticides associated with storm runoff. The current study incorporated wetland mesocosm sampling following simulated runoff events using chlorpyrifos, atrazine, and metolachlor. Through this data collection and simple model analysis,...

  2. 78 FR 8407 - Endosulfan; Pesticide Tolerance

    Science.gov (United States)

    2013-02-06

    ... AGENCY 40 CFR Part 180 Endosulfan; Pesticide Tolerance AGENCY: Environmental Protection Agency (EPA). ACTION: Order reestablishing tolerance. SUMMARY: EPA has granted an objection to the timing of the revocation of the tolerance for endosulfan on tea. The objection was filed by the Chamber of ] Commerce...

  3. 77 FR 26450 - Metconazole; Pesticide Tolerances

    Science.gov (United States)

    2012-05-04

    ... with metconazole follows. A. Toxicological Profile EPA has evaluated the available toxicity data and... of Departure/Levels of Concern Once a pesticide's toxicological profile is determined, EPA identifies........... increased spleen wt (F) and hepatic vacuolation (M). Dermal short-term and Quantification of dermal risk...

  4. Sorption of pesticides to aquifer minerals

    DEFF Research Database (Denmark)

    Clausen, Liselotte; Fabricius, Ida Lykke

    2000-01-01

    This paper summarizes results from a work were the sorption of five pesticides on seven minerals were studied in order to quantify the adsorption to different mineral surfaces. Investigated mineral phases are: quartz, calcite, kaolinite, a-alumina, and three iron oxides (2-line ferrihydrite, goet...

  5. 77 FR 60311 - Chlorantraniliprole; Pesticide Tolerances

    Science.gov (United States)

    2012-10-03

    ... chlorantraniliprole does not pose a cancer risk to humans. Therefore, a dietary exposure assessment for the purpose of... tolerances in cattle, meat; goat, meat; horse, meat; and sheep, meat to 0.1 ppm. The reason for these changes... from aggregate exposure to the pesticide chemical residue, including all anticipated dietary...

  6. 75 FR 19272 - Thifensulfuron methyl; Pesticide Tolerances

    Science.gov (United States)

    2010-04-14

    ... to the pesticide chemical residue, including all anticipated dietary exposures and all other... the relationship of the results of the studies to human risk. EPA has also considered available... thyroid/parathyroid weights in female dogs. There were no gross or histopathological changes reported...

  7. Screening of pesticides for environmental partitioning tendency.

    Science.gov (United States)

    Gramatica, Paola; Di Guardo, Antonio

    2002-06-01

    The partitioning tendency of chemicals, in this study pesticides in particular, into different environmental compartments depends mainly on the concurrent relevance of the physico-chemical properties of the chemical itself. To rank the pesticides according to their distribution tendencies in the different environmental compartments we propose a multivariate approach: the combination, by principal component analysis, of those physico-chemical properties like organic carbon partition coefficient (Koc), n-octanol/water partition coefficient (Kow), water solubility (Sw), vapour pressure and Henry's law constant (H) that are more relevant to the determination of environmental partitioning. The resultant macrovariables, the PC1 and PC2 scores here named leaching index (LIN) and volatality index (VIN), are proposed as preliminary environmental partitioning indexes in different media. These two indexes are modeled by theoretical molecular descriptors with satisfactory predictive power. Such an approach allows a rapid pre-determination and screening of the environmental distribution of pesticides starting only from the molecular structure of the pesticide, without any a priori knowledge of the physico-chemical properties.

  8. Earthworms, pesticides and sustainable agriculture: a review.

    Science.gov (United States)

    Datta, Shivika; Singh, Joginder; Singh, Sharanpreet; Singh, Jaswinder

    2016-05-01

    The aim of this review is to generate awareness and understand the importance of earthworms in sustainable agriculture and effect of pesticides on their action. The natural resources are finite and highly prone to degradation by the misuse of land and mismanagement of soil. The world is in utter need of a healthy ecosystem that provides with fertile soil, clean water, food and other natural resources. Anthropogenic activities have led to an increased contamination of land. The intensification of industrial and agricultural practices chiefly the utilization of pesticides has in almost every way made our natural resources concave. Earthworms help in a number of tasks that support many ecosystem services that favor agrosystem sustainability but are degraded by exhaustive practices such as the use of pesticides. The present review assesses the response of earthworm toward the pesticides and also evaluates the relationship between earthworm activity and plant growth. We strictly need to refresh and rethink on the policies and norms devised by us on sustainable ecology. In an equivalent way, the natural resources should be utilized and further, essential ways for betterment of present and future livelihood should be sought.

  9. 78 FR 44444 - Mancozeb; Pesticide Tolerances

    Science.gov (United States)

    2013-07-24

    ... document applies to them. Potentially affected entities may include: Crop production (NAICS code 111). Animal production (NAICS code 112). Food manufacturing (NAICS code 311). Pesticide manufacturing (NAICS... crops: Apples: 45%; asparagus: 30%; barley: 2.5%; cantaloupes: 15%; carrots: 2.5%; celery: 2.5%; corn: 2...

  10. 76 FR 23882 - Metiram; Pesticide Tolerances

    Science.gov (United States)

    2011-04-29

    ... entities may include, but are not limited to those engaged in the following activities: Crop production (NAICS code 111). Animal production (NAICS code 112). Food manufacturing (NAICS code 311). Pesticide... estimated the PCT for existing uses as follows: Apple, 65%; asparagus, 30%; barley, 2%; beans, dried, 2.5...

  11. 75 FR 24421 - Tebuconazole; Pesticide Tolerances

    Science.gov (United States)

    2010-05-05

    ... entities may include, but are not limited to those engaged in the following activities: Crop production (NAICS code 111). Animal production (NAICS code 112). Food manufacturing (NAICS code 311). Pesticide... Health Risk Assessment to support tolerances in/on Asparagus, Barley, Beans, Beets, Brassica leafy greens...

  12. 78 FR 24094 - Azoxystrobin; Pesticide Tolerances

    Science.gov (United States)

    2013-04-24

    ... applies to them. Potentially affected entities may include: Crop production (NAICS code 111). Animal production (NAICS code 112). Food manufacturing (NAICS code 311). Pesticide manufacturing (NAICS code 32532... follows: Almonds, 25%; apricots, 10%; artichokes, 25%; asparagus, 2.5%; green beans, 10%; blackberries, 5...

  13. 77 FR 16544 - Pesticide Product Registration Approvals

    Science.gov (United States)

    2012-03-21

    ... MBI-203 EP Bioinsecticide (EPA Reg. No. 84059-10) for use on agricultural and greenhouse crops... for Submission: For MBI-203 EP Bioinsecticide (EPA Reg. No. 84059-10), EPA is requiring submission of... Biologicals, Inc. submitted applications to amend three pesticide products: TAE-001 Technical Bioinsecticide...

  14. Interaction between alginates and manganese cations: identification of preferred cation binding sites.

    Science.gov (United States)

    Emmerichs, N; Wingender, J; Flemming, H-C; Mayer, C

    2004-04-01

    Algal and bacterial alginates have been studied by means of 13C NMR spectroscopy in presence of paramagnetic manganese ions in order to reveal the nature of their interaction with bivalent cations. It is found that the mannuronate blocks bind manganese cations externally near their carboxylate groups, while guluronate blocks show the capability to integrate Mn2+ into pocket-like structures formed by adjacent guluronate residues. In alternating mannuronate-guluronate blocks, manganese ions preferentially locate in a concave structure formed by guluronate-mannuronate pairs. Partial acetylation of the alginate generally reduces its capability to interact with bivalent cations, however, the selectivity of the binding geometry is conserved. The results may serve as a hint for the better understanding of the alginate gelation in presence of calcium ions.

  15. Induction of morphogenesis in Geodermatophilus by inorganic cations and by organic nitrogenous cations.

    Science.gov (United States)

    Ishiguro, E E; Wolfe, R S

    1974-01-01

    Morphogenesis of Geodermatophilus strain 22-68 involves two stages, a motile rod (R form) and an irregularly shaped cluster of coccoid cells (C form). A variety of mono- and divalent cations have been found to induce R-form to C-form morphogenesis and to maintain the organism in the C form. Concentration optima for all cations exceeded 100 mM. Results indicated that uptake of cations was accompanied by extrusion of intracellular protons, causing an increase in intracellular pH. A variety of organic amines also induced morphogenesis. Organic amines were taken up in the dissociated free base form, causing the intracellular pH to rise. None of these compounds was utilized as a carbon or nitrogen source.

  16. Agricultural pesticide usage and prioritization in South Korea.

    Science.gov (United States)

    Cha, Eun Shil; Jeong, Mihye; Lee, Won Jin

    2014-01-01

    This study aims to review agricultural pesticide usage and trends and to identify hazardous pesticides for regulation, in terms of public health, in South Korea. The authors collected data on usage and trends of agricultural pesticides through agriculture-related databases. Criteria from the US Environmental Protection Agency classification for carcinogenicity, World Health Organization classification for acute toxicity, and European Union prioritization list for endocrine-disrupting chemicals were used for the hazard categorization of identified individual active ingredients. Pesticides to be prioritized among all pesticides used in South Korea between 2007 and 2011 were selected by taking into account the volume of usage, toxicity, and epidemiological evidence. Annual agricultural use of pesticides has increased rapidly from the 1970s to 1990s in South Korea, but has declined since 2001. The quantity of pesticides used in 2011 was reported as 19,131 tons, and was comprised of 34.7% insecticides, 28.0% fungicides, and 27.1% herbicides. The 50 pesticides with the greatest volume of usage accounted for 82.6% of the total volume of pesticides used between 2007 and 2011, with the most-used active ingredient being machine oil, followed by mancozeb and then paraquat. Organophosphates were the most used among the top 50 pesticides. A total of 24 pesticides were selected for recommendation of intensive regulation in South Korea. In conclusion, the authors described the usage and trends of overall agricultural pesticides, which would serve as a fundamental step forward in managing pesticide in terms of public health. Intensive efforts are required for the prevention of potential health effects from the 24 identified pesticides.

  17. Removal of pesticides from white and red wines by microfiltration

    Energy Technology Data Exchange (ETDEWEB)

    Doulia, Danae S., E-mail: ntoulia@mail.ntua.gr [Laboratory of Organic Chemical Technology, School of Chemical Engineering, National Technical University of Athens, Zografou Campus, 9 Iroon Politechniou, GR-15780 Athens (Greece); Anagnos, Efstathios K. [Laboratory of Organic Chemical Technology, School of Chemical Engineering, National Technical University of Athens, Zografou Campus, 9 Iroon Politechniou, GR-15780 Athens (Greece); Liapis, Konstantinos S. [Pesticide Residue Laboratory, Benaki Phytopathological Institute, 7 Ekalis Str., Kiphissia, Athens GR-14561 (Greece); Klimentzos, Demetrios A. [Laboratory of Organic Chemical Technology, School of Chemical Engineering, National Technical University of Athens, Zografou Campus, 9 Iroon Politechniou, GR-15780 Athens (Greece)

    2016-11-05

    Highlights: • Various mixtures of 23 pesticides were determined by SPE and GC-ECD in wine. • The removal of pesticides is affected by the type of membrane and wine. • The higher the pesticide’s hydrophobicity, the higher its removal. • Antagonistic and synergistic effects of pesticides in wines were estimated. - Abstract: The aim of this work is the investigation of microfiltration in removing pesticides from a white and a red Greek wine. Six membranes with pore size 0.45 μm were investigated. Two mixtures of 23 and 9 pesticides, and single pesticide solutions were added in the wine. The pesticides tested belong to 11 chemical groups. Solid phase extraction (SPE) followed by gas chromatography (GC) with electron capture detector (ECD) were performed to analyze pesticide residues of the filtered fortified wine. Distinct behavior was exhibited by each membrane. Cellulose acetate and cellulose nitrate showed higher mean pesticide removal for both wines, followed by polyethersulfone, regenerated cellulose, and polyamides. The filtration effectiveness was correlated to the membrane type and to the pesticide chemical structure and properties (octanol-water partition coefficient, water solubility) and compared for the wines tested. In most cases, the more hydrophobic pesticides (pyrethroids and aldrin) showed higher removal from red wine than white wine. Adsorption on membranes was increased by increasing hydrophobicity and decreasing hydrophilicity of organic pesticide molecule. The removal of each pesticide from its single solution was generally higher than that from its mixtures, allowing the estimation of the antagonistic and synergistic effects of pesticides in the mixtures.

  18. Cationic niosomes an effective gene carrier composed of novel spermine-derivative cationic lipids: effect of central core structures.

    Science.gov (United States)

    Opanasopit, Praneet; Leksantikul, Lalita; Niyomtham, Nattisa; Rojanarata, Theerasak; Ngawhirunpat, Tanasait; Yingyongnarongkul, Boon-Ek

    2017-05-01

    Cationic niosomes formulated from Span 20, cholesterol (Chol) and novel spermine-based cationic lipids of multiple central core structures (di(oxyethyl)amino, di(oxyethyl)amino carboxy, 3-amino-1,2-dioxypropyl and 2-amino-1,3-dioxypropyl) were successfully prepared for improving transfection efficiency in vitro. The niosomes composed of spermine cationic lipid with central core structure of di(oxyethyl)amino revealed the highest gene transfection efficiency. To investigate the factors affecting gene transfection and cell viability including differences in the central core structures of cationic lipids, the composition of vesicles, molar ratio of cationic lipids in formulations and the weight ratio of niosomes to DNA. Cationic niosomes composed of nonionic surfactants (Span20), cholesterol and spermine-based cationic lipids of multiple central core structures were formulated. Gene transfection and cell viability were evaluated on a human cervical carcinoma cell line (HeLa cells) using pDNA encoding green fluorescent protein (pEGFP-C2). The morphology, size and charge were also characterized. High transfection efficiency was obtained from cationic niosomes composed of Span20:Chol:cationic lipid at the molar ratio of 2.5:2.5:0.5 mM. Cationic lipids with di(oxyethyl)amino as a central core structure exhibited highest transfection efficiency. In addition, there was also no serum effect on transfection efficiency. These novel cationic niosomes may constitute a good alternative carrier for gene transfection.

  19. Adverse events following pandemic A (H1N1 2009 monovalent vaccines in pregnant women--Taiwan, November 2009-August 2010.

    Directory of Open Access Journals (Sweden)

    Wan-Ting Huang

    Full Text Available BACKGROUND: During the 2009 H1N1 pandemic, pregnant women were prioritized to receive the unadjuvanted or MF59®-adjuvanted pandemic A (H1N1 2009 monovalent vaccines ("2009 H1N1 vaccines" in Taiwan regardless of stage of pregnancy. Monitoring adverse events following 2009 H1N1 vaccination in pregnant women was a priority for the mass immunization campaign beginning November 2009. METHODS/FINDINGS: We characterized reports to the national passive surveillance from November 2009 through August 2010 involving adverse events following 2009 H1N1 vaccines among pregnant women. Reports from the passive surveillance were matched to a large-linked database on a unique identifier, date of vaccination, and date of diagnosis in a capture-recapture analysis to estimate the true number of spontaneous abortion after 2009 H1N1 vaccination. We verified 16 spontaneous abortions, 11 stillbirths, 4 neonatal deaths, 4 nonpregnancy-specific adverse events, and 2 inadvertent immunizations in recipients who were unaware of pregnancy at time of vaccination. The Chapman capture-recapture estimator of true number of spontaneous abortion after 2009 H1N1 vaccination was 329 (95% confidence interval [CI] 196-553. Of the 14,474 pregnant women who received the 2009 H1N1 vaccines, the estimated risk of spontaneous abortion was 2.3 (95% CI, 1.4-3.8 per 100 pregnancies, compared with a local background rate of 12.8 (95% CI, 12.8-12.9 per 100 pregnancies. CONCLUSIONS: The passive surveillance provided rapid initial assessment of adverse events after 2009 H1N1 vaccination among pregnant women. Its findings were reassuring for the safety of 2009 H1N1 vaccines in pregnancy.

  20. Comparison of accelerated and rapid schedules for monovalent hepatitis B and combined hepatitis A/B vaccines in children with cancer.

    Science.gov (United States)

    Köksal, Yavuz; Varan, Ali; Aydin, G Burca; Sari, Neriman; Yazici, Nalan; Yalcin, Bilgehan; Kutluk, Tezer; Akyuz, Canan; Büyükpamukçu, Münevver

    2007-12-01

    The aim of this study was to determine the efficacy of immunization against hepatitis A and B infections with "rapid" or "accelerated" schedules in children with cancer receiving chemotherapy. Fifty-one children were recruited to receive either vaccination schedule, in the "rapid vaccination schedule"; hepatitis B (group I) or combined hepatitis A/B vaccines (group III) were administered at months 0, 1, 2, and 12; in the "accelerated vaccination schedule," hepatitis B (group II) or combined hepatitis A/B (group IV) vaccines were administered on days 0, 7, 21, and 365 intramuscularly. The seroconversion rates at months 1 and 3 were 35.7 and 57.1% in group I and 25 and 18.8% in group II, respectively. Group I developed higher seroconversion rates at month 3. In group III the seroconversion rates for hepatitis B at months 1 and 3 were 54.5 and 60% and in group IV 50 and 70%, respectively. For hepatitis A, the seroconversion rates at months 1 and 3 were 81.8 and 90% in group III and 80 and 88.9% in group IV, respectively. The accelerated vaccination schedule seems to have no advantage in children receiving cancer chemotherapy except for high antibody levels at month 1. In conclusion, the accelerated vaccination schedules are not good choices for cancer patients. The combined hepatitis A/B vaccine is more effective than monovalent vaccine in cancer patients, which probably can be explained by an adjuvant effect of the antigens. The seroconversion of hepatitis A by the combined hepatitis A/B vaccination is very good in cancer patients.

  1. Persistent organochlorine pesticides in Mexican butter.

    Science.gov (United States)

    Waliszewski, S M; Villalobos-Pietrini, R; Gómez-Arroyo, S; Infanzón, R M

    2003-04-01

    Organochlorine pesticides have been used in Mexico in malaria control programmes against ectoparasites and as seed dresser. Owing to their chemical stability, they tend to accumulate in the lipid part of the organisms. The stored pesticides are excreted with the endogenous fat during milk production. The aim was to monitor the organochlorine pesticide levels in butter manufactured in Mexico. From the pesticides, only HCB, beta-HCH, pp'-DDT, op'-DDT and pp'-DDE with major frequency and levels were detected. The HCB mean level was low at 0.008 mg kg(-1) on a fat basis. From the HCH isomer, only the beta-HCH at 0.065 mg kg(-1) on a fat basis was determined, remaining as the main contaminant of the monitored butters. Among DDTs, pp'-DDE was the major constituent (0.043 mg kg(-1) on a fat basis) followed by pp'-DDT (0.036 mg kg(-1)) and op'-DDT (0.009 mg kg(-1)). Comparing the previous study (1994) and this one (2001), all organochlorine pesticides had a descendent tendency; beta-HCH decreased from 0.095 to 0.065 mg kg(-1) on a fat basis, whereas the total DDT decreased from 0.056 to 0.047 mg kg(-1), pp'-DDT from 0.050 to 0.036 mg kg(-1), op'-DDT from 0.018 to 0.009 mg kg(-1), while pp'-DDE increased from 0.032 to 0.043 mg kg(-1). The decreased DDT levels in Mexican butters is caused by the substitution of organochlorine insecticides with pyrethroids used by the Mexican Ministry of Health since 1999 in sanitary programmes.

  2. Pesticide use and risk of end-stage renal disease among licensed pesticide applicators in the Agricultural Health Study

    Science.gov (United States)

    Lebov, Jill F.; Engel, Lawrence S.; Richardson, David; Hogan, Susan L.; Hoppin, Jane A.; Sandler, Dale P.

    2017-01-01

    Objectives Experimental studies suggest a relationship between pesticide exposure and renal impairment, but epidemiological evidence is limited. We evaluated the association between exposure to 41 specific pesticides and end-stage renal disease (ESRD) incidence in the Agricultural Health Study (AHS), a prospective cohort study of licensed pesticide applicators in Iowa and North Carolina. Methods Via linkage to the United States Renal Data System, we identified 320 ESRD cases diagnosed between enrollment (1993-1997) and December 2011 among 55,580 male licensed pesticide applicators. Participants provided pesticide use information via self-administered questionnaires. Lifetime pesticide use was defined as the product of duration and frequency of use and then modified by an intensity factor to account for differences in pesticide application practices. Cox proportional hazards models, adjusted for age and state, were used to estimate associations between ESRD and: 1) ordinal categories of intensity-weighted lifetime use of 41 pesticides, 2) poisoning and high-level pesticide exposures, and 3) pesticide exposure resulting in a medical visit or hospitalization. Results Positive exposure-response trends were observed for the herbicides alachlor, atrazine, metolachlor, paraquat, and pendimethalin, and the insecticide chlordane. More than one medical visit due to pesticide use (HR = 2.13; 95% CI: 1.17, 3.89) and hospitalization due to pesticide use (HR = 3.05; 95% CI: 1.67, 5.58) were significantly associated with ESRD. Conclusions Our findings support an association between ESRD and chronic exposure to specific pesticides and suggest pesticide exposures resulting in medical visits may increase the risk of ESRD. PMID:26177651

  3. Complex Macromolecular Architectures by Living Cationic Polymerization

    KAUST Repository

    Alghamdi, Reem D.

    2015-05-01

    Poly (vinyl ether)-based graft polymers have been synthesized by the combination of living cationic polymerization of vinyl ethers with other living or controlled/ living polymerization techniques (anionic and ATRP). The process involves the synthesis of well-defined homopolymers (PnBVE) and co/terpolymers [PnBVE-b-PCEVE-b-PSiDEGVE (ABC type) and PSiDEGVE-b-PnBVE-b-PSiDEGVE (CAC type)] by sequential living cationic polymerization of n-butyl vinyl ether (nBVE), 2-chloroethyl vinyl ether (CEVE) and tert-butyldimethylsilyl ethylene glycol vinyl ether (SiDEGVE), using mono-functional {[n-butoxyethyl acetate (nBEA)], [1-(2-chloroethoxy) ethyl acetate (CEEA)], [1-(2-(2-(t-butyldimethylsilyloxy)ethoxy) ethoxy) ethyl acetate (SiDEGEA)]} or di-functional [1,4-cyclohexanedimethanol di(1-ethyl acetate) (cHMDEA), (VEMOA)] initiators. The living cationic polymerizations of those monomers were conducted in hexane at -20 0C using Et3Al2Cl3 (catalyst) in the presence of 1 M AcOEt base.[1] The PCEVE segments of the synthesized block terpolymers were then used to react with living macroanions (PS-DPE-Li; poly styrene diphenyl ethylene lithium) to afford graft polymers. The quantitative desilylation of PSiDEGVE segments by n-Bu4N+F- in THF at 0 °C led to graft co- and terpolymers in which the polyalcohol is the outer block. These co-/terpolymers were subsequently subjected to “grafting-from” reactions by atom transfer radical polymerization (ATRP) of styrene to afford more complex macromolecular architectures. The base assisted living cationic polymerization of vinyl ethers were also used to synthesize well-defined α-hydroxyl polyvinylether (PnBVE-OH). The resulting polymers were then modified into an ATRP macro-initiator for the synthesis of well-defined block copolymers (PnBVE-b-PS). Bifunctional PnBVE with terminal malonate groups was also synthesized and used as a precursor for more complex architectures such as H-shaped block copolymer by “grafting-from” or

  4. Heart imaging with cationic complexes of technetium

    Energy Technology Data Exchange (ETDEWEB)

    Deutsch, E.; Bushong, W.; Glavan, K.A.; Elder, R.C.; Sodd, V.J.; Scholz, K.L.; Fortman, D.L.; Lukes, S.J.

    1981-10-02

    The cationic technetium-99 complex trans-(99TC(dmpe)2Cl2)+, where dmpe is bis(1,2-dimethylphosphino)ethane or (CH3)2P-CH2-P(CH3)2, has been prepared and characterized by single-crystal, x-ray structural analysis. The technetium-99m analog, trans-(99mTc(dmpe) 2Cl2)+, has also been prepared and shown to yield excellent gamma-ray images of the heart. The purposeful design, characterization, and synthesis of this technetium-99m radiopharmaceutical represents a striking application of fundamental inorganic chemistry to a problem in applied nuclear medicine.

  5. Aggregate Formed by a Cationic Fluorescence Probe

    Institute of Scientific and Technical Information of China (English)

    TIAN, Juan; SANG, Da-Yong; JI, Guo-Zhen

    2007-01-01

    The aggregation behavior of a cationic fluorescence probe 10-(4,7,10,13,16-pentaoxa-1-azacyclooctadecyl-methyl)anthracen-9-ylmethyl dodecanoate (1) was observed and studied by a fluorescence methodology in acidic and neutral conditions. By using the Py scale, differences between simple aggregates and micelles have been discussed. The stability of simple aggregates was discussed in terms of hydrophobic interaction and electrostatic repulsion. The absence of excimer emission of the anthrancene moiety of probe 1 in neutral condition was attributed to the photoinduced electron transfer mechanism instead of photodimerization.

  6. 40 CFR 158.2070 - Biochemical pesticides product performance data requirements.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Biochemical pesticides product... AGENCY (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Biochemical Pesticides § 158.2070 Biochemical pesticides product performance data requirements. Product performance data must be developed...

  7. 40 CFR 158.2160 - Microbial pesticides product performance data requirements.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Microbial pesticides product... AGENCY (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Microbial Pesticides § 158.2160 Microbial pesticides product performance data requirements. Product performance data must be developed...

  8. 40 CFR 158.510 - Tiered testing options for nonfood pesticides.

    Science.gov (United States)

    2010-07-01

    ... pesticides. 158.510 Section 158.510 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Toxicology § 158.510 Tiered testing options for nonfood pesticides. For nonfood use pesticides only, applicants have two options for generating and...

  9. 40 CFR 158.2130 - Microbial pesticides residue data requirements table.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Microbial pesticides residue data... (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Microbial Pesticides § 158.2130 Microbial pesticides residue data requirements table. (a) General. Sections 158.100 through 158.130 describe how to...

  10. 40 CFR 158.2120 - Microbial pesticides product analysis data requirements table.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Microbial pesticides product analysis... AGENCY (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Microbial Pesticides § 158.2120 Microbial pesticides product analysis data requirements table. (a) General. Sections 158.100 through...

  11. 40 CFR 152.20 - Exemptions for pesticides adequately regulated by another Federal agency.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Exemptions for pesticides adequately... PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS PESTICIDE REGISTRATION AND CLASSIFICATION PROCEDURES Exemptions § 152.20 Exemptions for pesticides adequately regulated by another Federal agency. The pesticides...

  12. 40 CFR 158.2030 - Biochemical pesticides product chemistry data requirements table.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Biochemical pesticides product... PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Biochemical Pesticides § 158.2030 Biochemical pesticides product chemistry data requirements table. (a) General. (1) Sections...

  13. 40 CFR 158.2171 - Experimental use permit microbial pesticides product analysis data requirements table.

    Science.gov (United States)

    2010-07-01

    ... pesticides product analysis data requirements table. 158.2171 Section 158.2171 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Microbial Pesticides § 158.2171 Experimental use permit microbial pesticides product analysis data requirements...

  14. 40 CFR 158.2172 - Experimental use permit microbial pesticides residue data requirements table.

    Science.gov (United States)

    2010-07-01

    ... pesticides residue data requirements table. 158.2172 Section 158.2172 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Microbial Pesticides § 158.2172 Experimental use permit microbial pesticides residue data requirements table. (a)...

  15. European Union policy on pesticides: implications for agriculture in Ireland.

    Science.gov (United States)

    Jess, Stephen; Kildea, Steven; Moody, Aidan; Rennick, Gordon; Murchie, Archie K; Cooke, Louise R

    2014-11-01

    European Community (EC) legislation has limited the availability of pesticide active substances used in effective plant protection products. The Pesticide Authorisation Directive 91/414/EEC introduced the principle of risk assessment for approval of pesticide active substances. This principle was modified by the introduction of Regulation (EC) 1107/2009, which applies hazard, the intrinsic toxicity of the active substance, rather than risk, the potential for hazard to occur, as the approval criterion. Potential impacts of EC pesticide legislation on agriculture in Ireland are summarised. While these will significantly impact on pesticide availability in the medium to long term, regulations associated with water quality (Water Framework Directive 2000/60/EC and Drinking Water Directive 1998/83/EC) have the potential to restrict pesticide use more immediately, as concerns regarding public health and economic costs associated with removing pesticides from water increase. This rationale will further reduce the availability of effective pesticide active substances, directly affecting crop protection and increasing pesticide resistance within pest and disease populations. In addition, water quality requirements may also impact on important active substances used in plant protection in Ireland. The future challenge for agriculture in Ireland is to sustain production and profitability using reduced pesticide inputs within a framework of integrated pest management.

  16. Occurrence, Distribution, and Accumulation of Pesticides in Exterior Residential Areas.

    Science.gov (United States)

    Jiang, Weiying; Conkle, Jeremy L; Luo, Yuzhou; Li, Juying; Xu, Karen; Gan, Jay

    2016-12-06

    Pesticides are commonly applied around residential homes, but their occurrence on exterior surfaces (e.g., pavement) has not been thoroughly evaluated. We collected 360 dust samples from curbside gutters, sidewalks, and street surfaces at 40 houses in southern California to evaluate pesticide occurrence on urban paved surfaces as well as their spatial and temporal distributions. Pesticides and select degradates were ubiquitously detected in dust, with the median concentration of total target analytes at 85 μg kg(-1). A total of 75% of samples contained at least five pesticides. As a result of recurring pesticide applications, concentrations increased throughout the summer. The pyrethroids bifenthrin and permethrin accounted for 55% of total pesticides detected in the dust. The highest concentrations in dust were found on the sidewalk and in the gutter. Relative to indoor environments, human exposure risk to pesticides on paved surfaces was estimated to be lower, with the highest potential oral and dermal exposure predicted to be 38 ng day(-1) for permethrin. The ubiquitous detection of pesticides on residential outdoor surfaces and the fact that the exterior concentrations did not correlate to the indoor areas highlight the necessity to measure pesticides in both indoor and outdoor areas for complete residential pesticide risk assessment.

  17. Environmental medicine, part 4: pesticides - biologically persistent and ubiquitous toxins.

    Science.gov (United States)

    Crinnion, W J

    2000-10-01

    Although the use of pesticides has doubled every ten years since 1945, pest damage to crops is more prevalent now than it was then. Many pests are now pesticide resistant due to the ubiquitous presence of pesticides in our environment. Chlorinated pesticide residues are present in the air, soil, and water, with a concomitant presence in humans. Organophosphate and carbamate pesticides - the compounds comprising the bulk of current pesticide use - are carried around the globe on air currents. Municipalities, schools, churches, business offices, apartment buildings, grocery stores, and homeowners use pesticides on a regular basis. Pesticides are neurotoxins that can cause acute symptoms as well as chronic effects from repeated low-dose exposure. These compounds can also adversely affect the immune system, causing cell-mediated immune deficiency, allergy, and autoimmune states. Certain cancers are also associated with pesticide exposure. Multiple endocrine effects, which can alter reproduction and stress-handling capacity, can also be found. Limited testing is available to assess the toxic overload of these compounds, including serum pesticide levels and immune system parameters. Treatment for acute or chronic effects of these toxins includes avoidance, supplementation, and possibly cleansing.

  18. Food processing as a means for pesticide residue dissipation

    Directory of Open Access Journals (Sweden)

    Đorđević Tijana

    2016-01-01

    Full Text Available Pesticides are one of the major inputs used for increasing agricultural productivity of crops. However, their inadequate application may produce large quantities of residues in the environment and, once the environment is contaminated with pesticides, they may easily enter into the human food chain through plants, creating a potentially serious health hazard. Nowadays, consumers are becoming more aware of the importance of safe and high quality food products. Thus it is pertinent to explore simple, cost-effective strategies for decontaminating food from pesticides. Various food processing techniques, at industrial and/or domestical level, have been found to significantly reduce the contents of pesticide residues in most food materials. The extent of reduction varies with the nature of pesticides, type of commodity and processing steps. Pesticides, especially those with limited movement and penetration ability, can be removed with reasonable efficiency by washing, and the effectiveness of washing depends on pesticide solubility in water or in different chemical solvents. Peeling of fruit and vegetable skin can dislodge pesticide residues to varying degrees, depending on constitution of a commodity, chemical nature of the pesticide and environmental conditions. Different heat treatments (drying, pasteurization, sterilization, blanching, steaming, boiling, cooking, frying or roasting during various food preparation and preservation processes can cause losses of pesticide residues through evaporation, co-distillation and/or thermal degradation. Product manufactures, from the simplest grain milling, through oil extraction and processing, juicing/pureeing or canning of fruits and vegetables, to complex bakery and dairy production, malting and brewing, wine making and various fermentation processes, play a role in the reduction of pesticide contents, whereby each operation involved during processing usually adds to a cumulative effect of reduction of

  19. Electronic absorptions of the benzylium cation

    Science.gov (United States)

    Dryza, Viktoras; Chalyavi, Nahid; Sanelli, Julian A.; Bieske, Evan J.

    2012-11-01

    The electronic transitions of the benzylium cation (Bz+) are investigated over the 250-550 nm range by monitoring the photodissociation of mass-selected C7H7+-Arn (n = 1, 2) complexes in a tandem mass spectrometer. The Bz+-Ar spectrum displays two distinct band systems, the S1←S0 band system extending from 370 to 530 nm with an origin at 19 067 ± 15 cm-1, and a much stronger S3←S0 band system extending from 270 to 320 nm with an origin at 32 035 ± 15 cm-1. Whereas the S1←S0 absorption exhibits well resolved vibrational progressions, the S3←S0 absorption is broad and relatively structureless. Vibronic structure of the S1←S0 system, which is interpreted with the aid of time-dependent density functional theory and Franck-Condon simulations, reflects the activity of four totally symmetric ring deformation modes (ν5, ν6, ν9, ν13). We find no evidence for the ultraviolet absorption of the tropylium cation, which according to the neon matrix spectrum should occur over the 260 - 275 nm range [A. Nagy, J. Fulara, I. Garkusha, and J. Maier, Angew. Chem., Int. Ed. 50, 3022 (2011)], 10.1002/anie.201008036.

  20. Photodissociation of Cerium Oxide Nanocluster Cations.

    Science.gov (United States)

    Akin, S T; Ard, S G; Dye, B E; Schaefer, H F; Duncan, M A

    2016-04-21

    Cerium oxide cluster cations, CexOy(+), are produced via laser vaporization in a pulsed nozzle source and detected with time-of-flight mass spectrometry. The mass spectrum displays a strongly preferred oxide stoichiometry for each cluster with a specific number of metal atoms x, with x ≤ y. Specifically, the most prominent clusters correspond to the formula CeO(CeO2)n(+). The cluster cations are mass selected and photodissociated with a Nd:YAG laser at either 532 or 355 nm. The prominent clusters dissociate to produce smaller species also having a similar CeO(CeO2)n(+) formula, always with apparent leaving groups of (CeO2). The production of CeO(CeO2)n(+) from the dissociation of many cluster sizes establishes the relative stability of these clusters. Furthermore, the consistent loss of neutral CeO2 shows that the smallest neutral clusters adopt the same oxidation state (IV) as the most common form of bulk cerium oxide. Clusters with higher oxygen content than the CeO(CeO2)n(+) masses are present with much lower abundance. These species dissociate by the loss of O2, leaving surviving clusters with the CeO(CeO2)n(+) formula. Density functional theory calculations on these clusters suggest structures composed of stable CeO(CeO2)n(+) cores with excess oxygen bound to the surface as a superoxide unit (O2(-)).