bluuebunny/crossref_metadata_2025_split huggingface dataset:
A kinetic analysis of an interaction model of phloem translocation
Authors: Aikman David P. 
Published: November 2006

AbstractThe kinetics of transport in phloem are discussed. The steady‐state behaviour is examined applying the thermodynamics of irreversible processes to a non‐specific model in which there are interactions between the rates of water flow, of solute flow and of the transduction of metabolic energy. It is predicted that the flow of solute will depend on its concentration gradient, as in apparent diffusion, on the passive driving force on water, as in a Münch system, and on the metabolism of the transport system, as in activated mass flow. The theoretical description of the long‐distance transport process includes the effect of gravity on volume flow and on exchange flow.A model in which exchange occurs between two streams of solution flowing in opposite directions is examined to explore the transient kinetics. If the flows are not symmetrical, then the observable behaviour of the system, after the decay of the initial wave fronts, may be approximated by a random walk in a moving frame of reference, i.e. apparent diffusion plus mass flow, thus supporting the conclusions of the steady state analysis.The predictions are discussed in relation to physiological evidence.
Hydrolysis of the triazine herbicide, cyanazine
Authors: Brown N. P. H. , Furmidge C. G. L. , Grayson B. T. 
Published: November 2006

AbstractThe hydrolysis of cyanazineCyanazine is the proposed common name for the herbicide sold under the Shell registered trade name BLADEX.
(2‐chloro‐4‐cyanoisopropylamino‐6‐ethylamino‐1,3,5‐triazine) has been studied using 14C‐ring labelled compound over a temperature range of 25° to 75 °C and over a range of pH values from 1.5 to 12. The activation energies and the activation entropy changes during hydrolysis showed there was a different mechanism under acid and alkaline conditions. The only product identified after hydrolysis in acid solutions was 2‐hydroxy‐4‐carboxyisopropylamino‐6‐ethylamino‐1,3,5‐triazine. In alkaline solution the same hydroxy‐acid was the end‐product, but 2‐chloro‐4‐amidoisopropylamino‐6‐ethylamino‐1,3,5‐triazine was isolated as an intermediate.The variation of the specific rate constants with temperature for hydrolytic catalysis by H+, OH− was determined, thus enabling the hydrolytic half‐life of cyanazine to be calculated at any pH and temperature.
Flight‐tunnel experiments with red‐billed queleas to determine the distribution of a solution sprayed onto birds in flight
Authors: Ward P. , Pope G. G. 
Published: November 2006

AbstractIn an attempt to simulate conditions when Quelea birds are sprayed with avicide at night while they are in flight, captive birds were sprayed with red dye as they flew down a dark tunnel. The distribution of dye on the birds' plumage showed that the spray makes contact with the front of the head, the upper breast, and the flight feathers of the wing; very little reaches any other part of the body. Large droplets (180 to 250 μm) were much more effective than small droplets (30 to 75 μm) at hitting the flying bird, presumably because the latter were carried over the body surfaces by the airstream.
Determination of carbon tetrachloride in fumigated cereal grains during storage
Authors: Scudamore K. A. , Heuser S. G. 
Published: November 2006

AbstractAlternative methods for the extraction of unchanged carbon tetrachloride residues from fumigated whole and ground wheat and maize were examined and compared. Amounts of carbon tetrachloride extracted were determined by gas‐liquid chromatography using two separate columns and an electron‐capture detector. A portion of any carbon tetrachloride residue was found to be converted to chloroform by a steam distillation extraction method but not when a cold solvent extraction process was used. In addition, the effectiveness of removal of carbon tetrachloride from wheat and maize during a 3.5 h steam distillation was progressively lessened, in comparison with the cold extraction process, as the length of time that residual fumigant had been associated with the grain increased.The rate of elimination of carbon tetrachloride from wheat and maize during airing at two temperatures was determined and though partially dependent on the temperature of fumigation, airing was consistently more rapid at 25° than at 10°C. Initial residues of 200 to 400 parts/million in whole grains fell to 1 to 10 parts/million when aired for six months in thin layers at 25°C and to 5 to 50 parts/million at WC. Residues in wheat disappeared more rapidly than those in maize. Grinding initially caused a sharp reduction in carbon tetrachloride content but subsequent airing rates were little faster than those of the whole grains.It is concluded that complete elimination of trace amounts of carbon tetrachloride from products of treated grain is unlikely even after milling but the toxicological significance of such residues is uncertain.
Detoxication of metal drums from emulsifiable concentrate formulations of parathion
Authors: Archer T. E. , Hsieh D. P. H. 
Published: November 2006

AbstractMetal drums of various sizes which had contained a parathion emulsifiable concentrate were found to retain significant amounts of residues after the containers were completely drained. The residual pesticide formulation was removed from the emptied containers by washing with water and organic solvents. Efficient removal of the parathion by water followed by washing with a water‐miscible organic solvent has been demonstrated. It is possible that these washings could be disposed of by combining them into the spray mixture. These procedures suggest a simple and economical way of container decontamination.
A technique for applying small drops of insecticide solution to Myzus persicae (sulz.)
Authors: Needham P. H. , Devonshire A. L. 
Published: November 2006

AbstractA technique is described for applying insecticide solutions accurately and rapidly to aphids. Radiochemical measurements showed that volume of 0.02 to 0.2 μl could be applied accurately and that more than 90% of the dose remained on the aphids when 0.08 μl or less was applied. There was good agreement between the radiochemical calibration land the toxicological results.
Uptake and distribution of thiabendazole by seed potatoes
Authors: Tisdale M. J. , Lord K. A. 
Published: November 2006

AbstractThe uptake of thiabendazole into potato seed tubers (cultivar King Edward) was determined by the method of application, more being taken up from solutions and suspensions than from dusts. Penetration and uptake were greatest with solutions at pH 3, and less at higher or lower pHs. The addition of inorganic salts (KCl, CaCl2) had no effect. Treatment of tubers with weak solutions of mineral acid increased uptake of thiabendazole. There was little movement and no metabolism of the chemical when potatoes were stored for 3 months.
Gel filtration clean‐up for multi‐residues of organophosphorus pesticides in rice
Authors: Masud Z. , Bátora V. , Kovačičová J. 
Published: November 2006

AbstractGel filtration on Bio‐Beads S‐X8 and Sephadex LH‐20 columns has been successfully applied to the clean‐up of multiple residues of malathion, fenitrothion and dichlorvos in rice. Recoveries were checked by gas‐liquid chromatography using CsBr‐thermionic detector and ranged from 77 to 104% at 5 mg/kg level. The clean‐up was found to be highly effective. No interference was observed in the gas chromatograms.
A method for determining the volatility of active ingredients used in plant protection
Authors: Gückel W. , Synnatschke G. , Rittig R. 
Published: November 2006

AbstractThe paper describes a gravimetric method of determining the volatility (evaporation rate) of pesticides. The measuring apparatus may be set at any temperature between ∼15 and 80°C; the dry air flowing through the apparatus is regulated by valves between ‐0.2 1/h and 300 1/h.Figures available for vapour pressure reveal a mathematical relation between vapour pressure and evaporation rate. This can be used as a simple method of determining the vapour pressure of any substance at 20°C by determining the evaporation rate when the air current is flowing at 50 l/h. The effects of the temperature and the air flow rate on the evaporation rate are also analysed.
Interactions of carotenoids with some organophosphorus insecticides
Authors: Seifert J. , Davídek J. 
Published: November 2006

AbstractThe interactions of some organophosphorus insecticides (OPI) with carotenoids from oranges were studied in vitro. In the initial step, 5,6‐epoxy (di‐epoxy) xanthophylls are isomerised to 5,8‐furano (di‐furano) xanthophylls. This reaction can also be brought about by hydrogen ions. Degradation products of OPI or impurities present in commercial samples may be acidic. Subsequent reactions lead to complete loss of the long wavelength chromophore.
Assay of hypocholesterolaemic agents for antifungal activity
Authors: Matolcsy G. , Hamrán M. , Bordás B. 
Published: November 2006

AbstractThe presence of steroids, mainly of ergosterol, in the protoplasmic membrane of fungi provides a potential target for selective antifungal action. Several nonsteroidal hypocholesterolaemic agents used in human chemotherapy were tested for fungitoxicity. Most of the compounds, especially those of the phenyl‐ and phenoxyalkanecarboxylic acid type (I‐V) as well as the bis‐aminomethyl‐cyclohexane derivative (VII) revealed a moderate antifungal activity, encouraging further studies on this line.
Residual effects of fungicidal spray programmes on apple trees
Authors: Byrde Robert J. W. , Harper Christopher W. , Holgate Margaret E. , Hunter Thomas 
Published: November 2006

AbstractSpraying programmes for apple scab and mildew control sometimes had residual effects for one or even two years. Thus, benomyl (0.025% a.i.) and pyridinitril (0.035% a.i.) drastically reduced the subsequent incidence of cankers caused by Nectria galligena on young wood. Apple scab fruit infection, caused by Venturia inaequalis, was also less on trees on which benomyl had been used in the previous season. In the bark of such trees, toxic residues equivalent to 1 to 4 μg benomyl/g fresh wt. were detected by bioassay 7 months after spraying.
Photochemical transformation of thiophanate‐methyl and thiophanate to alkyl benzimidazol‐2‐yl carbamates
Authors: Buchenauer Heinrich , Edgington Lloyd V. , Grossmann Friedrich 
Published: November 2006

AbstractThe systemic fungicides thiophanate‐methyl (TPM) and thiophanate (TPE) were transformed in aqueous solutions on glass by irradiation with u.v. and sunlight to the more effective fungitoxic substances methyl benzimidazol‐2‐yl carbamate (MBC) and ethyl benzimidazol‐2‐yl carbamate (EBC), respectively.The thiophanate fungicides were not converted when incubated in the dark. The photochemical transformation of TPM and TPE to the corresponding alkyl benzimidazol‐2‐yl carbamates increased with the exposure time of u.v. irradiation.However, no light catalysed reactions occurred when both fungicides were irradiated with u.v. light in the solid state. The residue of TPM and TPE on leaves of cotton plants following spray application were transformed by the energy of sunlight to the more fungitoxic MBC and EBC.
Metabolism of choline in the rhizosphere and its possible influence on plant growth
Authors: Jones R. Gareth Wyn , Rippin Anthony J. , Storey Richard 
Published: November 2006

AbstractThe addition of choline chloride (1 mM) to the rooting medium of Zea mays seedlings as well as enhancing salt tolerance, caused the pH of the medium to drop rapidly by 1.5 to 2.0 pH units in 24 h. This compares with a drop of 0.2 to 0.3 pH units in the presence of NH4+ under equivalent conditions. In pot experiments choline treatment promoted the growth of maize and other species under alkaline conditions more effectively than NH4+. The acidification of the root medium was due to choline catabolism by bacteria, characterised as a strain of Pseudomonas fluorescens, introduced into the medium by the seedling roots. Choline is probably metabolised by the organism via betaine aldehyde and betaine to sarcosine. The acidification step is associated with the oxidation of betaine aldehyde to betaine. The possible role of rhizosphere pH changes and the modification of plant metabolism by chemicals found in the soil are discussed in relation to plant growth under natural conditions.
Mercury and organochlorine residue analysis of fish and aquatic mammals
Authors: Holden Alan V. 
Published: November 2006

AbstractAnalyses of fish for mercury, as both methylmercury and total mercury, have been necessary in view of the relatively high concentrations found as compared with most foodstuffs. Gas chromatography and flameless atomic absorption spectro‐photometry are the most commonly‐used techniques, and versions of these methods are described. Organochlorine residues, of both pesticide and industrial origin, are of considerable ecological interest as the result of food‐chain magnification, and the techniques for their analysis in aquatic species, and problems arising from other contaminants are discussed.
Organophosphorus and carbamate detection system
Authors: Ruzicka Joseph H. A. 
Published: November 2006

AbstractRecent progress on the separation and identification of organophosphorus and carbamate pesticides is reviewed. Emphasis has been placed on t.l.c. and g.l.c. methods. Newer techniques, including high pressure liquid chromatography and the use of microwave‐excited plasmas as detectors for gas chromatography, are discussed.
The isolation and possible significance of some toxic mammalian metabolites of diazinon
Authors: Machin Antony F. 
Published: November 2006

AbstractThe recognition and isolation of toxic metabolites of diazinon by gas, thin‐layer, column and high‐pressure liquid chromatography is discussed. The possible toxicological significance of these compounds is considered and some preliminary attempts to assess their importance by experiments with microsomal preparations are mentioned.
Residues of the carbamate acaricide, 3‐methyl‐5‐isopropylphenyl‐N(n‐butanoyl)‐N‐methylcarbamate (promacyl) and two metabolites in the tissues and milk of cattle
Authors: Clegg Donald E. , Martin Peter R. 
Published: November 2006

AbstractIn order to assess some of the residue characteristics of the experimental carbamate acaricide, 3‐methyl‐5‐isopropylphenyl‐N‐(n‐butanoyl‐)‐N‐methylcarbamate (promacyl) a 0.2 % aqueous emulsion was applied to cattle in a series of five trials and in a sixth, the technical product was added to the feed of stalled cattle.A method of analysis involving the formation of a derivative suitable for gas chromatographic analysis on electron capture detection mode was developed.Separate estimations of levels of the parent compound and the metabolites, 3‐methyl‐5‐isopropylphenyl ‐N‐methylcarbamate and 3‐methyl‐5‐ isopropylphenol, were carried out on fatty tissues and butterfat but for non‐fatty tissues “total” levels, which were a combined estimate of 3‐methyl‐5‐isopropylphenol itself and all substances hydrolysable to it, were estimated and quoted as Promacyl.The highest group average level of the parent compound was 0.9 part/million in fatty tissues 24 h after the last of 8 applications at 3 day intervals. In a single spray trial the maximum group average of 0.7 part/million in fatty tissues 24 h after treatment fell to 0.2 part/million after 5 days.Residues in butterfat, 7 h after a single dermal application showed a maximum level of 1.2 parts/million and this declined to 0.1 part/million on the seventh day after treatment.“Total” residues in non‐fatty tissues were of the order of 1/10 those found in fatty tissues.
Simazine dealkylation in conjunction with citrus roots
Authors: Jordan Lowell S. , Jolliffe Virgil A. 
Published: November 2006

AbstractSimazine (2‐chloro‐4,6‐bis(ethylamino)‐s‐triazine) was metabolised by dealkylation in the presence of citrus tree roots growing in nutrient solution. Dehalogenation to hydroxysimazine was not observed. Removal of citrus roots from the solution caused dealkylation to cease. Dealkylation did not occur in the nutrient solution in the absence of roots.
Fungicidal activity and chemical constitution XXT. The fungitoxicity of aliphatic polyamines
Authors: Brown David , Woodcock David 
Published: November 2006

AbstractFifteen polyamines have been prepared and shown to inhibit spore germination of Penicillium expansum and Neurospora crassa in vitro, but not Erysiphe graminis, Sphaerotheca fuliginea or Podosphaera leucotricha; no activity was shown against S. fuliginea on marrow seedlings or P. leucotricha on apple seedlings. Spermine homologues were considerably more active than spermidine homologues, but greatest activity was shown by the two naturally occurring compounds.
The biochemical mechanisms of resistance to insecticides with especial reference to the housefly, Musca domestica and aphid, Myzus persicae
Authors: Devonshire Alan L. 
Published: November 2006

AbstractThe mechanisms by which insects chemically modify and thereby resist insecticides, and the techniques used to study this metabolism arc described. The enzymes associated with the endoplasmic reticulum of the cell (the microsomal enzymes) play a major and ubiquitous role in this metabolism which can produce molecules either more or less toxic than the insecticide applied. “Soluble” enzymes in the cytoplasm of the cell also metabolise insecticides, and it is the balance between these types of metabolism and such factors as the rate of penetration of the insecticide and the susceptibility of the target which determines the tolerance of an insect to a particular insecticide. A very small change in one of these factors can cause a large change in the dose of insecticide required to kill an insect.
Distribution and persistence of Chlormequat in potato plants
Authors: Dekhuijzen H. M. , Bodlaender K. B. A. 
Published: November 2006

AbstractThe distribution and persistence of chlormequat was determined chemically in chlormequat treated potato plants and in the progeny from their tubers.Chlormequat penetrated into the leaves, was translocated to the tubers and accumulated in the underground parts. Potato tubers harvested from chlormequattreated plants produced temporarily dwarfed plants.In the progeny of tubers, the compound was translocated to all parts of the plant, the highest amounts being found in the underground parts. A loss of only 18 ± 2% occurred between planting the seed tubers and harvesting the potato plants 2 months later.
Determination of dimetridazole in pig tissue II. Residues after administration in the feed or drinking water
Authors: Parnell Michael J. 
Published: November 2006

AbstractResidues of dimetridazole (1,2‐dimethyl‐5‐nitroimidazole) in the tissues of pigs after administration of the drug are reported. Three dosing regimes were examined, administration of 0.05% dimetridazole in the feed for a period of 1 month, administration of 0.05% dimetridazole in the feed for a period of 2 months, and administration of 0.05% dimetridazole in the drinking water for a period of 1 week. The maximum drug level found was 6.9 μg/ml in the plasma of a pig after one week's medication with dimetridazole in the drinking water. Depletion of the drug was rapid and 48 h after the withdrawal of medication tissue levels of the drug were invariably less than 0.1 μg/g.
Procedures for Analysis of Surface Spray Deposits of Captafol on Coffee Trees, Captan on Apple Trees and Endosulfan on Hops by Gas‐Liquid Chromatography
Authors: Cooke Barry K. 
Published: November 2006

AbstractThe procedures involve the removal of captafol, captan or endosulfan spray deposits from the plant surfaces with solvent and their measurement by g.l.c. In contrast to residue analysis, clean‐up procedures are avoided and the speed of the methods enable large numbers of samples to be processed in the monitoring of initial spray deposits and the subsequent redistribution or loss in relation to the efficiency of spray application techniques. Recoveries of captafol and captan suspension deposits from glass were greater than 96%: recoveries of emulsion deposits from plant surfaces were greater than 95% for captafol, 93% for captan and 96% for endosulfan.
Organic pesticides. XV. Synthesis and insecticidal activity of some compounds containing phosphorus and fluorine
Authors: Joshi Krishna C. , Tholia Mani Kant 
Published: November 2006

AbstractForty new organofluorine compounds, containing phosphorus, have been synthesised as potential pesticides. The compounds include esters of O,O‐dialkyl phosphoramidic acids of the type (RO)2P(O)NHAr; thioesters of O,O‐dialkyl thiophosphoramidic acids of the type (RO)2P(S)NHAr; esters of O,O‐dialkyl phosphonic acid of the type (RO)2P(O)Ar and esters of O,O‐dialkyl thiophosphonic acid (RO)2P(S)OAr. All the compounds have been screened for their insecticidal activity against adult cockroaches (Periplanata americana) and a few show appreciable activity.
Hydrolysis rate and In vitro anticholinesterase activity of fenitrothion and S‐methyl fenitrothion
Authors: Kovačičová J. , Bátora V. , Truchlik Š 
Published: November 2006

AbstractAnticholinesterase activity in vitro of pure fenitrothion, S‐methyl fenitrothion (SMF) and mixtures of both was studied using different sources of cholinesterase. SMF was two to three orders as active an inhibitor as fenitrothion. In the mixtures, 1 and 5% SMF significantly influenced the I50 value of fenitrothion. The hydrolysis rates of both compounds are given. A method for the synthesis of pure SMF is also described.
Transport of the systemic fungicide cela W 524 (triforine) in barley plants. II. Uptake and metabolism
Authors: Bruchhausen V. V. , Stiasni M. 
Published: November 2006

AbstractAfter soil drench application of triforine (5 mg) to 35 barley plants in pots, a maximum of 7.5 μg a.i./g shoots (fresh weight) was found on the second day. The biological (effective) half‐life was 9 to 10 days. Doses of 50 mg resulted in impaired absorption rather than increased foliar concentration.On day 8 piperazine comprised 20% of the radioactivity of the four metabolites found in the shoots. An additional metabolite appears solely in the soil.
Rational herbicide design by synthesis of inhibitors for the peroxidase catalysed oxidation of indolyl‐3‐acetic acid
Authors: Wright Brian J. , Dowsett John R. , Rubery Philip H. , Baillie Alister C. , Corbett John R. 
Published: November 2006

AbstractAn attempt has been made to design a herbicide by synthesising active site directed irreversible inhibitors for the peroxidase‐catalysed oxidation of indolyl‐3‐acetic acid (IAA). A variety of substituted indoles were prepared and found to bind reversibly to the enzyme, but none produced any progressive inhibition, nor showed any herbicidal activity. This may be related to the fact that the inhibitors can be degraded by peroxidase in vitro since, if this occurred in the plant, the compounds could not then interfere with IAA oxidation.
Studies in phytotoxicitya. II. Changes in the concentrations of tricarboxylic acid cycle intermediates associated with phytotoxic effects on leaves
Authors: Milward Anthony. F. , Deas Adrian H. B. , Skerrett E. John 
Published: November 2006

AbstractLeaves of dwarf bean and blackcurrant were analysed for their content of some of the acids of the tricarboxylic acid (TCA) cycle after treatment with lime sulphur in order to correlate any changes with the increase in respiration previously reported.In the dwarf bean, a rapid initial decrease in succinic acid was followed by a large increase. This suggested that there was some blocking of the succinic dehydrogenase by the toxic agent. However it is probably important to consider the contribution of the hexose monophosphate (HMP) shunt in the increased respiration and associated metabolic changes as it has been shown that many disruptive agents, both chemical and biological, favour respiration by the HMP rather than the TCA route in plants.