bluuebunny/crossref_metadata_2025_split huggingface dataset:
Comparative effects of vetiver oil, nootkatone and disodium octaborate tetrahydrate on Coptotermes formosanus and its symbiotic fauna
Authors: Maistrello Lara , Henderson Gregg , Laine Roger A 
Published: December 2002

AbstractThe potential of vetiver oil and nootkatone as wood treatments against Coptotermes formosanus Shiraki was examined by assessing the effects on termite tunneling, feeding activity and survival, and the consequences on the symbiont protozoa responsible for wood digestion. Comparisons were made with non‐treated wood (control), wood treated with the borate compound Tim‐Bor® (a commonly used lumber preservative) and absence of a food source (starved termites), using choice and no‐choice tests. All wood slices were prepared at the same time using a 10 g liter−1 solution of each substance and were tested in four different sessions over one year to investigate longevity of the effects. Termites had to tunnel through sand to exploit the food sources, consisting of two wood slices, placed on opposite sides of the experimental enclosure. No‐choice tests showed that in the presence of vetiver oil or nootkatone, tunneling activity was always the lowest; wood consumption, termite survival and flagellate numbers and species distribution were significantly different from the control and similar to the results obtained for starved termites and with Tim‐Bor–treated wood. Nootkatone negatively affected termites for 12 months and was longer lasting than vetiver oil. In choice tests, when vetiver oil or nootkatone were present, termites exhibited a significant preference for non‐treated wood. Our results confirmed both the toxicity and absence of repellency of Tim‐Bor®. Vetiver oil and especially nootkatone affected Formosan subterranean termites and their protozoa, acting as arrestants, repellents and feeding deterrents, and represent a promising natural alternative for the control of this invasive pest.© 2002 Society of Chemical Industry
Synthesis and insecticidal activity of benzoheterocyclic analogues of N′‐benzoyl‐N‐(tert‐butyl)benzohydrazide: Part 2. Introduction of substituents on the benzene rings of the benzoheterocycle moiety
Authors: Sawada Yoshihiro , Yanai Toshiaki , Nakagawa Harumi , Tsukamoto Yoshihisa , Yokoi Shinji , Yanagi Mikio , Toya Tetsuya , Sugizaki Hiroyasu , Kato Yasuhito , Shirakura Hidetoshi , Watanabe Tetsuo , Yajima Yoshimi , Kodama Seiichirou , Masui Akio 
Published: December 2002

AbstractA series of N′‐benzoheterocyclecarbonyl‐N‐tert‐butyl‐3,5‐dimethylbenzohydrazide analogues possessing a variety of substituents on the benzene rings of the benzoheterocyle moieties were synthesized and tested for their insecticidal activity. The introduction of a methyl group at the R1 position of the benzoheterocycle moiety strongly increased the insecticidal activity. Among the analogues synthesized, N′‐tert‐butyl‐N′‐(3,5‐dimethylbenzoyl)‐5‐methyl‐6‐chromanecarbohydrazide showed the highest insecticidal activity (LC50 = 0.89 mg litre−1).© 2002 Society of Chemical Industry
Acaricidal activity of Cnidium officinale rhizome‐derived butylidenephthalide against Tyrophagus putrescentiae (Acari: Acaridae)
Authors: Kwon Ji‐Hoon , Ahn Young‐Joon 
Published: December 2002

AbstractThe acaricidal activity of materials derived from the rhizome of Cnidium officinale Makino against Tyrophagus putrescentiae Schrank adults was examined using direct contact application and fumigation methods, and compared with that of benzyl benzoate and N,N‐diethyl‐m‐toluamide (DEET). The biologically active constituent of the Cnidium rhizome was identified as butylidenephthalide by spectroscopic analyses. On the basis of 24‐h LD50 values, acaricidal activity was more pronounced with butylidenephthalide (5.80 µg cm−2) than with benzyl benzoate (9.75 µg cm−2) and DEET (16.26 µg cm−2). In typical poisoning symptoms, butylidenephthalide resulted in lethargy of treated mites, leading to death without knockdown, whereas benzyl benzoate and DEET caused death associated with uncoordinated behaviour. In a fumigation test with T putrescentiae adults, butylidenephthalide was much more effective in closed containers than in open ones, indicating that the effects of this compound were largely due to action in the vapour phase. Naturally occurring C officinale rhizome‐derived materials merit further study as potential T putrescentiae control agents or as lead compounds.© 2002 Society of Chemical Industry
Mechanisms of resistance to organophosphorus insecticides in populations of the obliquebanded leafroller Choristoneura rosaceana (Harris) (Lepidoptera: Tortricidae) from southern Ontario
Authors: Pree David J , Whitty Karen J , Bittner Lori A , Pogoda Mitchell K 
Published: December 2002

AbstractPopulations of Choristoneura rosaceana (Harris) from orchards in Ontario were shown to be resistant to azinphos‐methyl and to other types of organophosphorus insecticides. Resistance extended to methyl carbamates and to methomyl. The laboratory population used for these assays and selected with azinphosmethyl was also resistant to the pyrethroid, cypermethrin. Resistance was associated with increased esterase activity and was reduced by the addition of the synergist DEF. IEF studies of esterases also indicated increased activity in resistant populations, but did not identify any unique esterases associated with the resistance. Resistance was highly correlated (r = 0.78) with elevated esterases but not with increased glutathione‐S transferase activity (r = 0.13). Other mechanisms did not appear to be related.For the Department of Agriculture and Agri‐Food, Government of Canada, © Minister of Public Works and Government Services Canada 2002. Published for SCI by John Wiley & Sons, Ltd.
Isolation of a Pseudomonas fluorescens metabolite/exotoxin active against both larvae and pupae of vector mosquitoes
Authors: Prabakaran G , Paily K P , Padmanabhan V , Hoti S L , Balaraman K 
Published: December 2002

AbstractA formulation was developed from the metabolite(s) of a novel Pseudomonas fluorescens Migula strain (VCRC B426) and tested against 4th‐instar larvae and pupae of three species of vector mosquitoes, Anopheles stephensi Liston, Culex quinquefasciatus Say and Aedes aegypti (L). The larvae and pupae of An stephensi were the most susceptible to the formulation, followed by those of C quinquefasciatus and Ae aegypti, in that order, and the dosage requirement for pupal mortality was less than that required for larval mortality. The LC50 dosage requirements for larvae of these mosquito species were, respectively, 70.4, 511.5 and 757.3 µg protein ml−1, whereas for pupae they were, respectively, 2.0, 9.4 and 19.2 µg protein ml−1. The lethal fraction was purified from the culture broth and its molecular mass, as determined by high performance liquid chromatography, was 44 kDa. This is the first report of a microbial formulation acting upon mosquito pupae, a non‐feeding stage. Its mode of action and efficacy to control mosquitoes under field conditions need to be studied further.© 2002 Society of Chemical Industry
Susceptibility of field populations of adult Bemisia tabaci Gennadius (Homoptera: Aleyrodidae) and Eretmocerus sp (Hymenoptera: Aphelinidae) to cotton insecticides in Burkina Faso (West Africa)
Authors: Otoidobiga Lenli C , Vincent Charles , Stewart Robin K 
Published: December 2002

AbstractResearch was conducted in 14 cotton fields (3–10 ha) selected in seven localities (two fields per locality) in Burkina Faso, with the objectives of: (1) estimating Bemisia tabaci Gennadius (Homoptera: Aleyrodidae) population abundance, (2) assessing the levels of parasitism by Encarsia spp and Eretmocerus spp (Hymenoptera: Aphelinidae) and (3) estimating the susceptibilities of the pest and of an Eretmocerus sp to the insecticides currently sprayed on cotton. Yellow sticky cards and a leaf‐turning technique were used to estimate adult B tabaci population densities. Yellow sticky cards were also used to estimate the densities of adult Eretmocerus sp and the susceptibilities of B tabaci to insecticides. Leaf disk techniques were used to estimate B tabaci red eye nymph populations and parasitism by Encarsia spp and Eretmoceus spp was evaluated using stereo‐microscopy. A leaf cage technique was used to estimate the susceptibilities of Eretmocerus sp to insecticides. A mean of 6.5–27.4 adult B tabaci were trapped per yellow sticky card and 5.5 to >34.9 were counted per leaf using the leaf turning technique. There were 0.14–13 Eretmocerus sp trapped per yellow sticky card. The levels of parasitism varied between 36 and 87% by the end of the season and parasitism by Eretmocerus sp predominated in most of the fields. The susceptibilities of B tabaci and Eretmocerus sp varied from field to field and with the insecticide tested.© 2002 Society of Chemical Industry
Diaryloxyacetate herbicides
Authors: Smith Michael G , Lo William C , Jacks Wendy , Moore Susan , Pernich Daniel J , Subramanian Mani V , Turner James A 
Published: December 2002

AbstractThe discovery and investigation of a novel family of herbicides containing a diaryl acetal are described. The stability of the acetal limited herbicidal efficacy and recognizing that fact led to the design of analogs with commercial levels of post‐emergence activity on broadleaf weeds. These compounds inhibited acetolactate synthase and in vitro activity data were used to guide target design. However, no members of this family provided a commercially valuable combination of herbicidal efficacy and crop selectivity.© 2002 Society of Chemical Industry
Identification of the aromatase inhibitor aminoglutethimide in urine by gas chromatography/mass spectrometry
Authors: Mareck U. , Sigmund G. , Opfermann G. , Geyer H. , Schänzer W. 
Published: December 2002

AbstractAminoglutethimide is used therapeutically as an aromatase inhibitor in the treatment of metastatic breast cancer in post‐menopausal women. For doping purposes, aminoglutethimide may be used for treatment of adverse effects of an extensive abuse of anabolic androgenic steroids (gynaecomastia) and to increase the testosterone concentration and stimulation of testosterone biosynthesis. The use of aromatase inhibitors has been prohibited for male athletes since September 1, 2001. The purpose of this study was to develop methods for the identification of the parent compound or its main metabolite and the inclusion of this information into established screening procedures in doping analysis. An excretion study was conducted using oral application of one single therapeutic dose (500 mg) of Orimeten®. The analysis was performed by gas chromatography/mass spectrometry (GC/MS). Aminoglutethimide is excreted almost totally as unconjugated parent compound and is detectable by different screening procedures for up to 165 h. Most suitable for the detection of aminoglutethimide is the screening procedure for heavy volatile nitrogen‐containing drugs (‘Screening 2’). However, since only competition samples are analysed in that screening procedure, the additional inclusion of aminoglutethimide in the screening procedure for anabolic androgenic agents (‘Screening 4’) is recommended. Full mass spectra and diagnostic ions for the analysis of aminoglutethimide are presented. Copyright © 2002 John Wiley & Sons, Ltd.
Direct analysis of volatile organic compounds in human breath using a miniaturized cylindrical ion trap mass spectrometer with a membrane inlet
Authors: Riter Leah S. , Laughlin Brian C. , Nikolaev Eugene , Cooks R. Graham 
Published: December 2002

AbstractMembrane introduction mass spectrometry (MIMS) coupled to a miniature mass spectrometer equipped with a cylindrical ion trap (CIT) analyzer was used to monitor the flavor components, 3‐phenyl‐2‐propenal and methyl salicylate, found in cinnamon and wintergreen candies, respectively, directly from human breath. The poly(dimethylsiloxane) (PDMS) membrane was operated in a trap‐and‐release mode, where the temperature of the membrane was cycled during the experiments, which permitted temporal resolution of the two compounds of interest, facilitating their observation in the complex sample. Under these thermally driven conditions, the 10–90% rise times for both compounds are similar (15 s for methyl salicylate, 17 s for 3‐phenyl‐2‐propenal), but the difference in diffusivity means that the signal for 3‐phenyl‐2‐propenal is delayed and the 10% point occurs 6 s later than that for wintergreen. Additional specificity needed for complex samples was gained by using tandem mass spectrometry. Copyright © 2002 John Wiley & Sons, Ltd.
Utility of three types of mass spectrometers for determining elemental compositions of ions formed from chromatographically separated compounds
Authors: Grange Andrew H. , Genicola Floyd A. , Sovocool G. Wayne 
Published: December 2002

AbstractConcentration factors of 1000 and more reveal dozens of compounds in extracts of water supplies. Library mass spectra for most of these compounds are not available, and alternative means of identification are needed. Determination of the elemental compositions of the ions in mass spectra makes feasible searches of commercial and chemical literature that often lead to compound identification. Instrumental capabilities that constrain the utility of a mass spectrometer for determining ion compositions for compounds that elute from a chromatographic column are scan speed, mass accuracy, linear dynamic range, and resolving power. Mass peak profiling from selected ion recording data (MPPSIRD) performed with a double‐focusing mass spectrometer provides the best combination of these capabilities. This technique provides unique ion compositions for ions of higher mass from compounds eluting from a gas chromatograph than can be obtained by orthogonal acceleration time‐of‐flight (oa‐TOF) or Fourier transform ion cyclotron resonance mass spectrometry. Multiple compositions are usually possible for an ion with a mass exceeding 150 Da within the error limits of the mass measurement. The correct composition is selected based on measured exact masses of the mass peak profiles resulting from isotopic ions higher in mass by 1 and 2 Da and accurate measurement of the summed abundances of these isotopic ions relative to the monoisotopic ion. A profile generation model (PGM) automatically determines which compositions are consistent with measured exact masses and relative abundances. The utility of oa‐TOF and double‐focusing mass spectrometry using ion composition elucidation (MPPSIRD plus the PGM) are considered for determining ion compositions of two compounds found in drinking water extracts and a third compound from a monitoring well at a landfill. Published in 2002 by John Wiley & Sons, Ltd.
Gas chromatography/mass spectrometric study of non‐commercial C‐4‐substituted 1,4‐dihydropyridines and their oxidized derivatives
Authors: López‐Alarcón C. , Squella J. A. , Núñez‐Vergara Luis J. , Baez H. , Camargo Cristián 
Published: December 2002

AbstractA gas chromatography/mass spectrometry (GC/MS) method for the qualitative and quantitative determination of the calcium‐channel antagonists C‐4‐substituted 1,4‐dihydropyridines, and their corresponding N‐ethyl derivatives, is presented. Also, the electrochemical oxidation and the reactivity of the compounds with alkyl radicals derived from 2,2′‐azobis‐(2‐amidinopropane) were monitored by GC/MS. Mass spectral fragmentation patterns for the C‐4‐substituted 1,4‐dihydropy‐ridine parent drugs were significantly different from those of their oxidation products, generated either by electrochemical oxidation or by reaction with alkyl radicals. However, for N‐ethyl‐1,4‐dihydropyridine compounds it was not possible to detect the final products (pyridinium salts) using these experimental conditions. Copyright © 2002 John Wiley & Sons, Ltd.
Liquid chromatography/electrospray tandem mass spectrometry characterization of styrene metabolism in man and in rat
Authors: Manini Paola , Andreoli Roberta , Poli Diana , De Palma Giuseppe , Mutti Antonio , Niessen Wilfried M. A. 
Published: December 2002

AbstractLiquid chromatography with electrospray tandem mass spectrometry was used to characterize the metabolism of styrene in man and in rat. To improve identification and characterization of minor styrene metabolites, rats were co‐exposed to styrene and styrene‐d8. In addition to the main styrene metabolites, mandelic acid and phenylglyoxylic acid, and specific mercapturic acids, phenylhydroxyethylmercapturic acids (PHEMAs), other minor metabolites, including phenylglycine, N‐acetyl‐S‐(phenacyl)cysteine, 4‐vinylphenol and styreneglycol conjugates (glucuronides and sulfates) were identified and determined both in human and rat urine. Phenylglycine and N‐acetyl‐S‐(phenacyl)cysteine have been hypothesized to occur, but never detected in human or rat urine after styrene exposure. 4‐Vinylphenol and styrene glycol had already been recognized as styrene metabolites, but never determined as intact glucuronide and sulfate conjugates. Failure to identify 1‐ and 2‐phenylethanol conjugates suggests that phenylethanol might be an intermediate metabolite, but it is not a conjugated catabolite. A method for the simultaneous determination of mandelic acid, phenylglyoxylic acid, phenyglycine and the four PHEMA diastereoisomers has been developed and validated. For those glucuronide and sulfate conjugates whose standards are not commercially available, a method for semiquantitative analysis, based on the use of structurally similar compounds as standards, has been developed. This approach was found to be valid for the determination of 4‐vinylphenol glucuronide and 4‐vinylphenol sulfate. Copyright © 2002 John Wiley & Sons, Ltd.
Quantitative analysis using gas chromatography/combustion/isotope ratio mass spectrometry and standard addition of intrinsically labelled standards (SAIL) –application to isoflavones in foods
Authors: Bluck Leslie J. C. , Jones Kerry S. , Thomas Jane , Liggins Jason , Harding Marilyn , Bingham Sheila A. , Coward W. Andrew 
Published: December 2002

AbstractWe have investigated a novel application of gas chromatography/combustion/isotope ratio mass spectrometry (GC/C/IRMS) for the quantitative analysis of the isoflavones in food matrices. Previous methods have been hampered by the lack of analytical standards to introduce early enough in the extraction procedure to allow compensations for losses at all stages of the procedure. In this work we have produced standard materials that can be added at the initial extraction, by intrinsically labelling soya plants by growing them in an atmosphere enriched in the stable isotope of carbon in CO2. On analysis these plants were shown to contain phytoestrogens at a high (up to 20%) level of enrichment. The dried plant material has been used to estimate the isoflavone concentrations of a set of spiked flours. For daidzein the methodology was shown to produce results comparable to those achieved by GC/MS techniques. The method was less successful for genistein, possibly due to the greater fragility of this compound under the conditions required for the analysis. Copyright © 2002 John Wiley & Sons, Ltd.
Studies on azaspiracid biotoxins. I. Ultrafast high‐resolution liquid chromatography/mass spectrometry separations using monolithic columns
Authors: Volmer Dietrich A. , Brombacher Stephan , Whitehead Bob 
Published: December 2002

AbstractIn this study, the performance of monolithic columns was evaluated for ultrafast liquid chromatography/mass spectrometry (LC/MS) analyses and for high‐resolution separations of several azaspiracid biotoxin analogs. Because of their high permeability, monolithic columns offer a number of advantages over conventional packed columns; viz., very low backpressures and relatively flat van Deemter curves at high flow rates. That is, very high flow rates can be used for ultrafast analyses or, by using longer than normal columns, high‐resolution separations are possible. In a series of experiments, we varied the mobile phase flow rates between 1 and 8 mL/min, and studied their impact on chromatographic parameters such as retention time, resolution, number of plates and pressure. The chromatographic run times could be reduced to ca. 30 s without a significant change in the separation efficiency. A signal intensity comparison revealed interesting differences between atmospheric‐pressure chemical ionization (APCI) and electrospray ionization (ESI) in their flow‐rate dependency. An explanation with respect to the behavior as of a mass‐flow or a concentration‐dependent device is given in the paper. Additionally, the column length was varied between 10 and 70 cm. As a result, the number of theoretical plates increased substantially. In the example shown in the report, an increase from 13 000 plates for a 10‐cm column to 80 000 for a 70‐cm column is demonstrated. In addition, the potential of the monolithic columns for high‐resolution LC/MS separations is shown for a complex biotoxin mixture, which was separated on a 40‐cm‐long column. Copyright © 2002 John Wiley & Sons, Ltd.
Investigation of the electrospray response of lysine‐, arginine‐, and homoarginine‐terminal peptide mixtures by liquid chromatography/mass spectrometry
Authors: Brancia Francesco L. , Openshaw Matthew E. , Kumashiro Sumio 
Published: December 2002

AbstractGuanidination has been used to investigate how modification of the lysine η‐amino group into the corresponding guanidino group affects response in electrospray (ES) mass spectrometry (MS). Selected ion monitoring (SIM) analysis of equimolar mixtures containing arginine‐, lysine‐ and the corresponding homoarginine‐terminal peptides following liquid chromatography (LC) showed differences in ES response. The ionisation behaviour of the standard peptides is in accordance with the postulated higher stability of the guanidino group present on arginine‐ and homoarginine‐terminal peptides. Modification of the separation conditions employed during LC demonstrates that relative abundances of electrosprayed peptides ions rely mostly on peptide structure. Copyright© 2002 John Wiley & Sons, Ltd.
Polyaniline‐coated nanoelectrospray emitters: performance characteristics in the negative ion mode
Authors: Bigwarfe Paul M. , White Thomas P. , Wood Troy D. 
Published: December 2002

AbstractThe increasing tendency to miniaturize analytical techniques has resulted in the widespread use of nanoelectrospray ionization mass spectrometry. A new polyaniline‐coated nanoelectrospray emitter has shown increasing promise as a more durable and stable alternative to traditional metal‐coated emitters. In this report, the utility of polyaniline‐coated nanoelectrospray emitters in the negative ion mode is investigated. Here, oligonucleotides and peptides have been ionized in the negative mode using polyaniline‐coated nanoelectrospray emitters. The emitters were found to be durable for at least an hour in the negative ion mode, during which time the signal was stable. The high amount of electrical discharge usually associated with negative ion mode nanoelectrospray was not problematic with the polyaniline‐coated emitters. These characteristics make possible the reliable coupling of low‐flow separations to negative ion nanoelectrospray without the worry of emitter failure during the course of the experiment. Copyright © 2002 John Wiley & Sons, Ltd.