bluuebunny/crossref_metadata_2025_split huggingface dataset:
Differences in light stability of some carboxylic acid anilide fungicides in relation to their applicability for seed and foliar treatment
Authors: Buchenauer Heinrich 
Published: November 2006

AbstractIrradiation of carboxin, furcarbanil, pyracarbolid, cyclafuramid, benodanil, mebenil and oxycarboxin by u.v. light (254 nm) for 4 h resulted in 97, 64, 58, 50, 20, 18 and 15% inactivation, respectively. Photoinactivation of the different compounds in aqueous solution or in the solid state was much slower in sunlight than in u.v. light and stability increased in the following order: carboxin < furcarbanil ≤ cyclafuramid ≤ pyracarbolid < mebenil ≤ benodanil < oxycarboxin. The residues of carboxin and furcarbanil on the leaf surface of bean plants were almost completely inactivated after 40 h exposure to sunlight; cyclafuramid lost 85% of its activity. The toxicity of leaf deposits of pyracarbolid, mebenil, benodanil and oxycarboxin decreased by 83, 53, 50 and 41%, respectively after 80 h in sunlight. The compounds with low photostability (e.g. carboxin, furcarbanil and cyclafuramid) are recommended mainly for controlling seed‐ and soil‐borne fungi; pyracarbolid, mebenil, oxycarboxin and benodanil, which proved to be more photostable, appear to be useful fungicides to control rust diseases. Among several photochemical decomposition products of carboxin detected, the sulphoxide and sulphone were identified.
Effect of some herbicides on freshwater algae
Authors: Robson T. Oxendale , Fowler Margaret C. , Barrett Philip R. F. 
Published: November 2006

AbstractThe activity of 12 herbicides was tested against various freshwater algae found in Britain. Three of the most troublesome species, Cladophora glomerata L., Rhizoclonium hieroglyphicum Katz., and Vaucheria dichotoma Ag. were all susceptible to methylthio‐1,3,5‐triazines. Terbutryne and cyanatryn were the most active and both killed C. glomerata and R. hieroglyphicum at 0.05 mg/litre. The concentration of terbutryne had to be increased to 0.1 mg/litre to control V. dichotoma. Asulam and WSCP (2.0 mg/litre), metflurazone and HZ5914 (1.0 mg/litre), copper sulphate (1.0 mg copper ion/litre) and cutrine (2.0 mg copper ion/litre) had no visible effect on the algae. Diquat (1.0 mg cation/litre) did, however, control C. glomerata and R. hieroglyphicum although, in natural conditions, the algae quickly recovered after treatment. Success with diquat (2.0 mg/litre) against V. dichotoma in laboratory experiments was not achieved in a field experiment.
Toxicity of pyrethroids to larvae of the Egyptian cotton leafworm, Spodoptera littoralis (Boisd.). II. Factors determining the effectiveness of permethrin at ultra‐low volume
Authors: Reay Richard C. , Ford Martyn G. 
Published: November 2006

AbstractFactors determining theeffectiveness of permethrinat ultra‐low volume against larvae of Spodoptera littoralis (Boisd.) were investigated using a modified Potter tower. Higher mass application rates for 95 % control were necessary when permethrin was used as a residual deposit compared with direct contact plus residual deposit action. Mortality was increased by adjusting droplet density, although the optimum number of drops/ unit area depended on the mass application rate. When mass application rate and droplet density were held constant, mortality increased inversely with the mean droplet diameter. The implications of these results for field applications are discussed.
The biochemical mode of action of some modern anthelmintics
Authors: Coles Gerald C. 
Published: November 2006

AbstractThe possible biochemical modes of action of levamisole, morantel, benzimidazoles and salicylanilides are discussed. It is concluded that the modes of action of none of these anthelmintics is properly understood, but it seems likely that levamisole and pyrantel act on the nematode nervous system, benzimidazoles affect cellular integrity and the uncoupling properties of salicylanilides could enable them to act at several sites.
Praziquantel—a new cestocidea
Authors: Thomas Herbert , Andrews Peter 
Published: November 2006

AbstractPraziquantel is a new chemotherapeutic agent with high activity against juvenile and adult cestodes. The juvenile cestodes tested include Hymenolepis nana, Cysticercus fasciolaris, C. pisiformis, C. tenuicollis, C. bovis. The fully effective doses range from 25–100 mg/kg host. All adult tapeworms tested (Taenia pisiformis, T. hydatigena, T. ovis, T. taenaiformis, Dipylidium caninum, Mesocestoides corti, Echinococcus multilocularis, E, granulosus) of dogs and cats and several Moniezia species of sheep were killed by doses up to 5 mg/kg host. Praziquantel is effective in vitro at very low concentrations. First studies on the mechanism of action in H. diminuta have shown that praziquantel acts on the carbohydrate metabolism of the parasite.
Stereochemical and chiral aspects in the synthesis of 3‐(2,2‐ dihalovinyl)‐2,2‐dimethylcyclopropanecarboxylic acids
Authors: Kondo Kiyosi , Takashima Toshiyuki , Negishi Akira , Matsui Kiyohide , Fujimoto Tamotsu , Sugimoto Kikuo , Hatch Charles E. , Baum Jonathan S. 
Published: November 2006

AbstractThe synthesis of (1RS)‐cis,trans‐3‐(2,2‐dichlorovinyl)‐2,2‐dimethylcyclopropanecarboxylic acid by dehydrohalogenation of 4,6,6,6‐tetrahalohexanoates has been modified to produce stereo‐selectively the cis‐isomer. A new stereospecific synthesis of cis‐3‐(2,2‐dihalovinyl)‐2,2‐dimethylcyclopropanecarboxylic acids using a bicyclic lactone and its extension to the preparation of the optically active (1R)‐cis acid are described.
Metabolic chemistry of pyrethroid insecticides
Authors: Casida John E. , Ruzo Luis O. 
Published: November 2006

AbstractThis review of studies on 20 pyrethroids with nine different acid moieties and ten different alcohol moieties reveals a diversity of functional groups undergoing metabolism in mammals, insects, other organisms, and microsomal esterase and oxidase systems. Seventy‐nine metabolites are identified from the cis‐isomer of permethrin and transpermethrin but fewer from other pyrethroids examined in less detail. The sites and rates of metabolic attack on each pyrethroid depend on the organism or system. Metabolism of pyrethoids by esterase and oxidase action usually limits their toxicity to mammals more than to insects, thereby conferring useful selective toxicity properties.
Reversed‐phase chromatography as a general method for determining octan‐1‐ol/water partition coefficients
Authors: Ellgehausen Holm , D'Hondt Christian , Fuerer Richard 
Published: November 2006

AbstractReversed‐phase high‐pressure liquid chromatography (h. p. l. c.) and thin‐layer chromatography (t. l. c.), on commercially available, reversed stationary phases, were used to determine the octan‐1‐ol/water partition coefficients (P) for 20 non‐ionic organic chemicals, consisting mainly of known pesticides in common use. Good correlation was found between log P values and both the logarithms of the capacity factor (k′), obtained by h. p. l. c., and the Rm values derived from t. l. c. The methods were found to be applicable over a range of more than six orders of magnitude in P values. In addition, the relation is shown between the P values of organic chemicals and their solubilities in water and in octan‐1‐01.
Antifeeding effect of cypermethrin and permethrin at sub‐lethal levels against Pieris brassicae larvae
Authors: Tan Keng‐Hong 
Published: November 2006

AbstractAn antifeeding (feeding deterrent) response by first‐ and fifth‐instar larvae of Pieris brassicae was shown to be significant at sub‐lethal levels of cypermethrin and permethrin, using leaf‐discs treated with the pyrethroids by dipping. Permethrin was slightly more effective than cypermethrin both as an insecticide and as an antifeedant against fifth‐instar larvae, but the reverse order of effectiveness was observed, with a marked difference in mortality, against newly‐hatched larvae. When 1‐day‐old fifth‐instar larvae were continuously given leaf discs treated with a solution of the pyrethroid (1 mg litre−1), up to the time of pupation, both cypermethrin and permethrin induced a significant extension of the larval period, with a reduction in the maximum larval and pupal weights, as well as a reduction in the total leaf‐area consumed. However, at higher levels of both pyrethroids, lowering the temperature induced some irritancy, as indicated by regurgitation and frequent uncoordinated wriggling movements of the fifth‐instar larvae. The advantages of cypermethrin as a protectant and as an antifeedant over permethrin are discussed.
Inactivation of deltamethrin on stored wheat
Authors: Hargreaves Phillip A. , Bengston Mervyn , Alder Jacquelin 
Published: November 2006

AbstractResidues of deltamethrin on wheat grain of 12% moisture content, stored in the laboratory at 25°C, remained constant within experimental error over a 15‐month interval. However, the biological activity of the residues against Sitophilus oryzae (L.) declined to 78% of the initial value at 3 months, and to 65% at 15 months after application. Inactivation of a proportion of the intact residues is indicated.
The pyrethrins and related compounds. Part XXVII. Esters of pulegenic and related acids
Authors: Elliott Michael , Janes Norman F. , Khambay Bhupinder P. S. 
Published: November 2006

AbstractA report by Staudinger and Ruzicka of the insecticidal activity of an ester of pulegenic acid with mixed naturally derived alcohols had not been examined further, and had been misinterpreted in a review. Therefore, two isomeric pulegenic and nine related acids were synthesised, characterised and esterified with modern, more effective, pyrethroidal alcohols. The pulegenic esters were inactive, but low activity was found in esters of acids in which the 5‐membered ring was additional to, rather than a replacement for, the cyclopropane ring.
Adsorption of systemic fungicides and a herbicide by some components of plant tissues, in relation to some physicochemical properties of the pesticides
Authors: Barak Eran , Dinoor Amos , Jacoby Benjamin 
Published: November 2006

AbstractLignin, an important component of plant tissues, adsorbed five systemic fungicides and one herbicide (carbendazim, triadimefon, nuarimol, triarimol, fenarimol and fluometuron) more strongly than bovine serum albumin, cellulose, ethylcellulose or sodium polygalacturonate. Significant correlations were found between the extent of the adsorption of the pesticides on the lignins extracted from three different plant species, and the log Poet (Poet is the octan‐1‐ol/water partition coefficient) of the compounds. The more lipophilic fungicides triarimol and fenarimol (log Poet about 2.6) were adsorbed to the greatest extent. Fluometuron, triadimefon and nuarimol (log Poet about 2.0) were moderately adsorbed, whereas carbendazim with the lowest log Poet (1.34 at pH 5.0), was adsorbed more than expected from its Poet value. The anomaly of carbendazim is discussed; it is ascribed to it's partial protonation at pH 5.0, whereas the other pesticides were non‐ionised.
The pattern of cross‐resistance to insecticides and juvenile hormone analogues in a diflubenzuron‐resistant strain of the cotton leaf worm Spodoptera littoralis boisd
Authors: El‐Guindy Mohsen A. , Abdel‐Sattar Mostafa M. , El‐Refai Abdel Rahman M. 
Published: November 2006

AbstractThe rate of development of resistance to diflubenzuron in a laboratory susceptible strain of the cotton leafworm Spodoptera littoralis Boisd., the pattern of cross‐resistance exhibited by the resistant strain to several insecticides and juvenile hormone analogues, as well as the synergistic action of piperonyl butoxide (PB) and S, S, S‐tributyl phosphorotrithioate (TBP) with insecticides or diflubenzuron on both strains, were investigated. Resistance to diflubenzuron increased slightly in the first eight selected generations and was enhanced by further selection until in generation 30, the selected strain attained the high level of resistance of 290.7‐fold, compared with the parent strain. The resistant strain when challenged with either insecticides or juvenile hormone analogues at selected generations (5, 10, 15, 20, 25 and 30) exhibited different levels of resistance to several insecticides representing organochlorine and organo‐phosphorus compounds, carbamates and pyrethroids, but a clear case of negative correlation was indicated between resistance to diflubenzuron and juvenile hormone analogues. With regard to the synergistic action of PB and TBP on the toxicity of either diflubenzuron or insecticides against the fourth‐instar larvae of the susceptible strain, methomyl showed slight levels of synergism when it was combined with them. With the exception of cypermethrin, which was not affected by the two synergists, lower levels of synergism were observed with the compounds endrin, diflubenzuron and fenvalerate when they were combined with the same synergists. These two synergists however, antagonised the toxic action of the organophosphorus compounds phosfolan and chlorpyrifos. Against the resistant strain, endrin was moderately synergised by TBP but only slightly by PB. Slight levels of synergism were observed when methomyl, phosfolan and diflubenzuron were combined with either synergist, but both antagonised chlorpyrifos and fenvalerate. Resistance to diflubenzuron and to the other tested chemicals in the resistant strain was scarcely affected by the two synergists.
The sub‐lethal activity of amidines on insects and acarids
Authors: Giles David P. , Rothwell David N. 
Published: November 2006

AbstractA number of straight‐chain and cyclic amidines at sub‐lethal concentrations elicit a variety of responses from target organisms, usually expressed as a disruption of normal behaviour, leading to reduced feeding of lepidopterous larvae and tick detachment, or reduced fecundity. These effects are particularly evident in Acarina and Lepidoptera, but can also be seen in members of other insect orders. In some previously unpublished experiments, it was demonstrated that some of these compounds act as ‘locomotor stimulants’ to decrease the feeding of lepidopterous larvae. This type of activity probably results from the interaction of these compounds with aminergic in the case of some compounds identified as octopaminergic neurotransmitter/neuromodulator systems in the target organisms. It is not always clear, however, to what extent this type of activity contributes to the control of pests in the field situation.
An experimental approach to the photolysis of pesticides adsorbed on soil: Thidiazuron
Authors: Klehr Meinolf , Iwan Jörg , Riemann Jürgen 
Published: November 2006

AbstractAn experimental procedure has been developed for conducting photolysis studies with pesticides adsorbed by soil surfaces. In these experiments, solutions of thidiazuron were sprayed on segments of a 0.5‐mm layer of soil covering a glass plate. The soil surface was irradiated using simulated sunlight. The light source was a xenon arc in combination with glass filters that absorbed light of wavelength <290 nm. During irradiation, one half of the sprayed areas was covered to obtain nonirradiated samples. After various time intervals, groups of three irradiated and three non‐irradiated segments of the soil were scraped off and extracted; the extracts were analysed. Information was obtained on the photoproducts formed and on the kinetics of photodegradation of thidiazuron.
The uptake of surfactants into wheat
Authors: Anderson Nicholas H. , Girling Jeanne 
Published: November 2006

AbstractThe time course of uptake has been determined for seven poly(oxyethylene) surfactants, and one anionic surfactant (sodium dodecyl sulphate), into the leaves of wheat plants grown in a phytotron. Uptake was relatively rapid during an initial period of 24 h for six of the eight surfactants; after this period, the uptake rate was lower, and total uptake after 48 h was in the range 80‐91% for those six surfactants. The other two compounds, sodium dodecyl sulphate and cetostearyl alcohol‐22EO condensate (hexadecan‐1‐ol/octadecan‐1‐ol ethylene oxide condensate; average number of ethylene oxide units 22) were barely taken up at all. The observed time course for uptake was consistent with a complex process based on more than one rate‐determining process. The physical properties of the surfactants are discussed in relation to their observed uptake behaviour. The surfactant deposit areas, measured by microscopy, were concluded to be not particularly relevant in interpreting the uptake results. Uptake was not related to surfactant chain length, but the physical form of the hydrated surfactant on a leaf surface appeared to influence uptake behaviour.
Malathion toxicity: Skeletal deformities in zebrafish (Brachydanio rerio, cyprinidae)
Authors: Kumar Kaushal , Ansari Badre A. 
Published: November 2006

AbstractToxicity tests reveal that the zebrafish (Brachydanio rerio) is very sensitive to malathion, an organophosphorus insecticide, and 24 to 96‐h LC50 values showed a gradual decrease as the exposure time was increased. Zebrafish exposed to long‐term sublethal concentrations failed to spawn and invariably exhibited skeletal deformities. Possible causes of the reduced gonadosomatic index and skeletal deformities are discussed.
Diastereoisomers and enantiomers of paclobutrazol: Their preparation and biological activity
Authors: Sugavanam Balasubramanyan 
Published: November 2006

AbstractPaclobutrazol is a highly active plant growth regulator with very good fungicidal activity. Aspects of the synthesis of paclobutrazol and its diastereoisomer are discussed, the resolution of paclobutrazol into its two enantiomers is described. It has been shown for the first time that it is possible to separate the plant growth regulatory activity from the fungicidal activity by resolution. Computer graphic studies are also included.
Increasing the sample size during clinical trials with t‐distributed test statistics without inflating the type I error rate
Authors: Timmesfeld Nina , Schäfer Helmut , Müller Hans‐Helge 
Published: November 2006

AbstractIn clinical trials with t‐distributed test statistics the required sample size depends on the unknown variance. Taking estimates from previous studies often leads to a misspecification of the true value of the variance. Hence, re‐estimation of the variance based on the collected data and re‐calculation of the required sample size is attractive. We present a flexible method for extensions of fixed sample or group‐sequential trials with t‐distributed test statistics. The method can be applied at any time during the course of the trial and does not require the necessity to pre‐specify a sample size re‐calculation rule. All available information can be used to determine the new sample size. The advantage of our method when compared with other adaptive methods is maintenance of the efficient t‐test design when no extensions are actually made. We show that the type I error rate is preserved. Copyright © 2006 John Wiley & Sons, Ltd.
The effect of docosahexaenoic acid on the electroretinogram of the guinea pig
Authors: Weisinger Harrison S. , Vingrys Algis J. , Sinclair Andrew J. 
Published: November 2006

AbstractDocosahexaenoic acid (DHA), an n‐3 polyunsaturated fatty acid, is found in consistently high concentrations in the retinae of mammals, yet its role in vision remains unclear. In this study, a mammalian model of variable retinal DHA concentration has been developed, such that the retinal phospholipids of guinea pigs contained between 2.5 and 30.8% DHA. Visual function was assessed using full‐field flash electroretinography, over a range of exposure levels spanning six log units. Trend analysis indicated that retinal function was altered by the tissue DHA level, and was described by a second‐order polynomial “inverted U‐shaped” function. The results suggested that although some amount of DHA is essential for normal retinal function increases in the DHA level past an optimal amount, found to be 19%, provided diminishing returns. In this study, manipulation of the retinal DHA level accounted for 21–35% of the electroretinographic variability.
Visual acuity and erythrocyte docosahexaenoic acid status in breast‐fed and formula‐fed term infants during the first four months of life
Authors: Hørby Jørgensen M. , Hernell O. , Lund P. , Hølmer G. , Fleischer Michaelsen K. 
Published: November 2006

AbstractIt has been recognized that preterm infants have a more rapid development of visual acuity if fed human milk or a formula enriched with the long‐chain polyunsaturated fatty acid (LCPUFA) docosahexaenoic acid (DHA) compared to a standard formula devoid of LCPUFA. Few studies have addressed whether the same is also true in term infants. The aim of the present study was to follow visual acuity and fatty acid composition in red blood cells (RBC) for the first 4 mon of life in 17 breast‐fed and 16 formula‐fed term infants. The formula used did not contain LCPUFA, but contained 1.7 wt% α‐linolenic acid, and the linoleic/α‐linolenic acid ratio was 8.5. The increase in visual acuity measured by Teller acuity cards developed more rapidly in breast‐fed infants compared to formula‐fed infants (P<0.001). This was parallelled by a decrease in DHA of RBC in formulafed infants, and with a significantly lower level at two and four months as compared to breast‐fed infants. The content of DHA in milk from the breast‐feeding mothers was high compared to other Western countries. The difference in visual acuity between the two feeding groups could be due to differences in DHA status as reflected by the RBC levels, but other explanations are possible. Intervention studies are required to verify if development of visual acuity in term formula‐fed infants is dependent on the DHA level of formula.
Effects of membrane charges and hydroperoxides on Fe(II)‐supported lipid peroxidation in liposomes
Authors: Tampo Yoshiko , Yonaha Masanori 
Published: November 2006

AbstractThe processes in producing a lag phase in Fe2+‐supported lipid peroxidation in liposomes were investigated. Incorporation of phosphatidylserine (PS) or dicetyl phosphate (DCP) into phosphatidylcholine [PC(A)] liposomes, which have arachidonic acid, produced a marked lag phase in Fe2+‐supported peroxidation, where PS was more effective than DCP. Phosphatidylcholine dipalmitoyl [PC(DP)] with a net‐neutral charge was still effective in producing a lag phase, though weak. Increasing concentrations of PS, DCP, and PC(DP) prolonged the lag period. Initially after adding Fe2+, slight oxygen consumption occurred in PC(A)/PS liposomes including hydroperoxides, followed by a lag phase. An increase in the hydroperoxide resulted in a shortening of the lag period. The initial events of Fe2+ oxidation accompanied by oxygen consumption were dependent on the hydroperoxide content, but significant changes in diene conjugation and hydroperoxide levels at this stage were not found. The molar ratios of both dis‐appeared Fe2+ and consumed O2 to preformed hydroperoxide in liposomes with or withouttert‐butylhydroxytoluene were constant, regardless of the different amounts of lipid hydroper‐oxides. The antioxidant completely inhibited the propagation of lipid peroxidation in the lipid phase, following a lag phase. In a model system containing 2,2′‐azobis (2‐amidinopropane) dihydrochloride, Fe2+ were consumed. We suggest that Fe2+ retained at a high level on membrane surfaces play a role in producing a lag phase following the terminating behavior of a sequence of free radical reactions initiated by hydroperoxide decompositin, probably by intercepting peroxyl radicals.