bluuebunny/crossref_metadata_2025_split huggingface dataset:
Impact of spray application methodology on the development of resistance to cypermethrin and spinosad by fall armyworm Spodoptera frugiperda (JE Smith)
Authors: Al‐Sarar Ali , Hall Franklin R , Downer Roger A 
Published: September 2006

AbstractThe development of resistance to an insecticide under various types of application method has yet to be reported in the literature. Five fall armyworm Spodoptera armigera (JE Smith) colonies were reared in a chamber for ten generations before starting topical application bioassays. From each colony, 200–500 third–fourth‐instar larvae were fed for 72 h on corn plants sprayed with cypermethrin or spinosad at minimum application rate (20 g ha−1) using a small droplet size nozzle XR8001VS (volume median diameter Dv0.5 = 163 µm) or a large droplet size nozzle XR8008VS (Dv0.5 = 519 µm). Surviving larvae were transferred to untreated corn leaves to complete their life cycle. Next‐generation third‐instar larvae of each colony were topically dosed with technical cypermethrin or spinosad at 1 µL per larva, and mortality was recorded 24 h post‐treatment. The results indicated that cypermethrin demonstrated an insecticidal activity greater than that of spinosad, and the cypermethrin regression lines moved to the right faster than those for spinosad, indicating an increased tolerance of cypermethrin. Generally, larvae from all generations (F1–F7) under the XR8008VS treatments were less susceptible to cypermethrin and developed resistance faster and to higher levels than larvae from the XR8001VS treatments. The confidence limits (95%) of LD50 for all spinosad treatments indicated that there was no significant difference from the LD50 value of the susceptible reference strain. The results are a first indication that application technology/insecticide reaction may affect the rapidity of resistance development in certain pest/plant scenarios, but field studies are needed to confirm this conclusion. Copyright © 2006 Society of Chemical Industry
Velvetbean (Mucuna pruriens) extracts: impact on Meloidogyne incognita survival and on Lycopersicon esculentum and Lactuca sativa germination and growth
Authors: Zasada Inga A , Klassen Waldemar , Meyer Susan LF , Codallo Maharanie , Abdul‐Baki Aref A 
Published: September 2006

AbstractVelvetbean (Mucuna spp.) is a summer annual that has been used as a cover crop to reduce erosion, fix nitrogen and suppress weeds and plant‐parasitic nematodes. Crude aqueous extracts (1:15 dry weight plant/volume water) were made from velvetbean plant parts, and various concentrations of the extracts were evaluated in vitro for toxicities to different stages of Meloidogyne incognita (Kofoid and White) Chitwood and for suppression of hypocotyl and root growth and inhibition of germination of tomato (Lycopersicon esculentum L.) and lettuce (Lactuca sativa L.). Germination was only affected by the full‐strength extract from leaf blades. Lettuce root growth was the most sensitive indicator of allelopathic activity of the plant part extracts. Lettuce and tomato root growth was more sensitive to the extract from main roots than to extracts of other plant parts, with lethal concentration (LC50) values of 1.2 and 1.1% respectively. Meloidogyne incognita egg hatch was less sensitive to extracts from velvetbean than the juvenile (J2) stage. There was no difference among LC50 values of the extracts from different plant parts against the egg stage. Based on LC50 values, the extract from fine roots was the least toxic to J2 (LC50 39.9%), and the extract from vines the most toxic (LC50 7.8%). The effects of the extracts were nematicidal because LC50 values did not change when the extracts were removed and replaced with water. Copyright © 2006 Society of Chemical Industry
Real‐time quantitative PCR assays for quantification of L1781 ACCase inhibitor resistance allele in leaf and seed pools of Lolium populations
Authors: Kaundun Shiv S , Cleere Sally M , Stanger Carole P , Burbidge Judith M , Windass John D 
Published: September 2006

AbstractThe I1781L amino acid substitution in the target ACCase enzyme causes broad resistance to ACCase inhibitor herbicides in several monocotyledenous weeds of agronomic importance. This mutation results from a substitution of an adenine (A) residue by either a thymine (T) or cytosine (C) at position 5341 in Alopecurus myosuroides Huds and at an equivalent position in Lolium species, Avena fatua L. and Setaria viridis (L.) Beauv. Two different procedures, the PCR‐based allele‐specific assay (ASA) and the derived cleaved amplified polymorphic sequence (dCAPS) method, have previously been described for detecting this mutation. These methods are, however, only amenable to low sample throughput and are used in the analysis of single plants. Here, an alternative high‐throughput ARMS/Scorpion real‐time quantitative PCR (Q‐PCR) method for measuring levels of the I1781L mutation in pools of leaf and seed samples of Lolium populations is presented. The limit of detection for C and T mutant alleles in a background of wild‐type A is 0.02 and 0.0003% respectively. In this study, DNA from batches of 24 leaf segments measuring 0.5 cm from different plants or 1000 seeds could be conveniently extracted and accurately analysed. As part of assay validation, the comparative analysis of five geographically distinct Lolium populations with dCAPS and Q‐PCR procedures demonstrated the accuracy of the latter method, and the three possible II1781, IL1781 and LL1781 ACCase genotypes being distributed as predicted by the Hardy–Weinberg principle. Given the dominance of the L1781 over the I1781 allele at recommended field rates for most ACCase inhibitors, the frequency of herbicide survivors in the field owing only to the presence of the I1781L mutation is thus predicted to be 2pq + q2, where p and q are the frequencies of the I1781 and L1781 alleles as determined by Q‐PCR. The Q‐PCR assay established allows detection of very low levels of the L1781 ACCase mutation before resistance would normally be discernible in the field. Therefore, it offers the opportunity to tackle resistance at its very onset, potentially avoiding implementation of complicated and often costly weed management practices. Copyright © 2006 Society of Chemical Industry
Insecticide resistance in vector mosquitoes in China
Authors: Cui Feng , Raymond Michel , Qiao Chuan‐Ling 
Published: September 2006

AbstractBecause of their special behaviour, physiology and close relationship with humans, mosquitoes act as one of the most important vectors of human diseases, such as filariasis, Japanese encephalitis, dengue and malaria. The major vector mosquitoes are members of the Culex, Aedes and Anopheles genera. Insecticides play important roles in agricultural production and public health, especially in a country with a huge human population, like China. Large quantities of four classes of insecticides, organochlorines, organophosphates, carbamates and pyrethroids, are applied annually to fields or indoors in China, directly or indirectly bringing heavy selection pressure on vector populations. The seven major species of vector mosquito in China are the Culex pipiens L. complex, C. tritaeniorhynchus Giles, Anopheles sinensis Wied., A. minimus Theobald, A. anthropophagus Xu & Feng, Aedes albopictus (Skuse) and Ae. aegypti L., and all have evolved resistance to all the above types of insecticide except the carbamates. The degree of resistance varies among mosquito species, insecticide classes and regions. This review summarizes the resistance status of these important vector mosquitoes, according to data reported since the 1990s, in order to improve resistance management and epidemic disease control, and to communicate this information from China to the wider community. Copyright © 2006 Society of Chemical Industry
Differential aphicidal effects of chitinase inhibitors on the polyphagous homopteran Myzus persicae (Sulzer)
Authors: Saguez Julien , Dubois Françoise , Vincent Charles , Laberche Jean‐Claude , Sangwan‐Norreel Brigitte S , Giordanengo Philippe 
Published: September 2006

AbstractFour chitinase inhibitors, cyclo‐(Proline‐Tyrosine), cyclo‐(Histidine‐Proline), allosamidin and psammaplin A, were selected for in vitro feeding experiments with the peach‐potato aphid, Myzus persicae (Sulzer), under controlled photoperiod and temperature conditions. Artificial diets were used to provide chitinase inhibitors at 10, 50 and 100 µg mL−1 to M. persicae. Except for cyclo‐(Proline‐Tyrosine), which did not modify aphid demographic parameters, chitinase inhibitors induced differential aphicidal effects on M. persicae. At all doses, cyclo‐(Histidine‐Proline) induced significant effects affecting daily fecundity, intrinsic rate of natural increase (rm) and doubling time of population. When compared with the control diet, allosamidin decreased nymph survival and daily fecundity, increasing the doubling time of population from 1 to 1.5 days. Psammaplin A was the most toxic inhibitor when delivered via artificial diet, as it induced the death of all aphids reared at 50 and 100 µg mL−1. The results demonstrate the potential use of chitinase inhibitors as aphid management tools. Copyright © 2006 Society of Chemical Industry
Solid‐phase synthesis of C‐terminally modified peptides
Authors: Ten Brink Hefziba T. , Meijer Joris T. , Geel Remon V. , Damen Mark , Löwik Dennis W. P. M. , van Hest Jan C. M. 
Published: September 2006

AbstractIn this paper, a straightforward and generic protocol is presented to label the C‐terminus of a peptide with any desired moiety that is functionalized with a primary amine. Amine‐functional molecules included are polymers (useful for hybrid polymers), long alkyl chains (used in peptide amphiphiles and stabilization of peptides), propargyl amine and azido propyl‐amine (desirable for ‘click’ chemistry), dansyl amine (fluorescent labeling of peptides) and crown ethers (peptide switches/hybrids). In the first part of the procedure, the primary amine is attached to an aldehyde‐functional resin via reductive amination. To the secondary amine that is produced, an amino acid sequence is coupled via a standard solid‐phase peptide synthesis protocol. Since one procedure can be applied for any given amine‐functional moiety, a robust method for C‐terminal peptide labeling is obtained. Copyright © 2006 European Peptide Society and John Wiley & Sons, Ltd.
A general treatment of three‐dimensional elasticity of quasicrystals by an operator method
Authors: Gao Yang , Zhao Bao‐Sheng 
Published: September 2006

AbstractBy an operator method, the general solution of three‐dimensional elasticity of quasicrystals is given constructively with some displacement functions, and its completeness is proved at the same time. Nonuniqueness and the scope of nonuniqueness of the general solution are also pointed out. The method used in the paper extends work from elasticity to quasicrystals elasticity. As two special cases, two‐dimensional dodecagonal quasicrystal and one‐dimensional hexagonal QCs are considered, and the general solutions based on the operator method are presented. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Optical transmission through three‐component Thue–Morse multilayers
Authors: Hu Xubo , Yang Xiangbo , Hu Wei , Guo Qi 
Published: September 2006

AbstractIn this paper, we study the transmission properties of the light through the aperiodic multilayers vertically following the three‐component Thue–Morse (3CTM) sequence. On the basis of the electromagnetic wave theory we present a so‐called decomposition‐substitution (DS) method to analyze the characteristics of the transmission directly and concisely. After predicting the transmission properties from the structure by means of the DS method, we then deduce the formulae of propagation matrices and transmission coefficients analytically and obtain the numerical simulations at the same time. The results obtained by three kinds of method accord with each other. It is found that the 3CTM systems possess an interesting tristable transmissive characteristic, which would be useful for designing some optical tristable devices. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The C–C pair in the vicinity of a bcc Fe bulk vacancy: electronic structure and bonding
Authors: Simonetti S. , Pronsato M. E. , Brizuela G. , Juan A. 
Published: September 2006

AbstractC–Fe and C–C interactions near a bcc Fe vacancy were analysed using DFT calculations. A cell containing 14 atoms was used to simulate the local environment of the Fe vacancy. Carbon atoms were positioned in their local energy minimum configurations. The most stable positions for the C atoms in the vacancy region were found at about 1.23 Å from the vacancy centre and near the first nearest‐neighbour octahedral sites. Changes in the electronic structure of Fe atoms near a vacancy were analysed. Fe–Fe bonds surrounding the vacancy weaken their bond when the C atoms are present. This bond weakening is a consequence of C–Fe bond formation. The Fe–C interactions occur mainly via Fe 4s orbitals with a lesser participation of Fe 3p orbitals. There is an electron transfer to the C atoms from their Fe nearest neighbours. The C–C interaction was also analysed. For the C–C distance of 1.462 Å, there is a bonding between the C atoms. The C–C interaction is stronger than the C–Fe interactions. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Computational prediction of grain size during rapid laser surface modification of Al–O ceramic
Authors: Samant Anoop N. , Dahotre Narendra B. 
Published: September 2006

AbstractThe aim of this letter is to present a model including the fundamental non‐equilibrium effects to predict the microstructure evolution during the rapid solidification of laser surface modified Al–O ceramic system to understand grain growth and the physical process involved during the treatment. The obtained data is then compared with the actual measurements from micrographs. This approach is novel compared to other work in the similar field which have looked at the process only at the macroscopic level that included the extractions of macroscopic features such as melt depth and width. Such study is important as laser surface modification can be extended to dressing of alumina grinding wheel material, a part of the Al–O ceramic system. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Antioxidative and In Vitro hepatoprotective activity of Bupleurum kaoi leaf infusion
Authors: Liu Chu‐Ting , Chuang Pei‐Ting , Wu Ching‐Yi , Weng Yih‐Ming , Chen Wenlung , Tseng Chin‐Yin 
Published: September 2006

AbstractThe roots of Bupleurus spp. have been used in traditional Chinese herbal medicine for curing liver diseases. Although bioactive saikosaponins have been detected in the leaves as well as in the roots, the aerial parts of the plants are discarded as waste. In the present study, a leaf infusion of B. kaoi Liu, Chao et Chuang, an indigenous Bupleurus species in Taiwan, was prepared and the antioxidant properties and in vitro hepatoprotective activity were demonstrated. The results show that the leaf infusion exerted DPPH free radical scavenging activity, inhibitory capacity on superoxide anion formation and superoxide anion scavenging activity. The hepatotoxicity of acetaminophen (APAP) and carbon tetrachloride (CCl4) on the rat liver cells were also decreased by the leaf infusion. Copyright © 2006 John Wiley & Sons, Ltd.
Delamination of multilayer packaging caused by exfoliating cream ingredients
Authors: Ortiz Gustavo , Garrido‐López Álvaro , Tena María Teresa 
Published: September 2006

AbstractExfoliating creams were packed in sachets of composite packaging consisting of polyethylene, aluminium and polyester layers stuck together by polyurethane adhesive, and they were kept in an oven at 40°C in order to accelerate the delamination process. The sachets were then delaminated and the resulting layers were analysed. A headspace solid‐phase microextraction mass spectrometry method (HS–SPME–GC–MS) using a 75µm carboxen polydimethylsiloxane fibre was used to identify the compounds migrating from the exfoliating creams through the polyethylene layer to the aluminium interface and suspected to be responsible for packaging delamination. Several volatile compounds used in the cosmetic industry as perfumes, fixing agents and preservatives, such as menthol, dihydromyrcenol and 2‐phenoxyethanol, were detected in the aluminium/polyester delaminated layer. The exfoliating creams were also analysed by HS–SPME–GC–MS. The study of loss of adhesion of the laminated material exposed to the exfoliating products revealed that the product with a higher concentration of 2‐phenoxyethanol caused a faster decrease in adhesion strength, but the lower adhesion values were found in products with higher concentrations of menthol and dihydromyrcenol. The results obtained showed that the analytical method used was suitable for identifying volatile compounds that migrate through polyethylene to the inner layers of the packaging of exfoliating products, as well as for providing prior information on which products may be difficult to package in sachets. Copyright © 2006 John Wiley & Sons, Ltd.
Simultaneous quantitative analysis of the antimalarials pyrimethamine and sulfamethoxypyrazine in plasma samples using liquid chromatography/tandem mass spectrometry
Authors: Storme Michael L. , Jansen F. Herwig , Goeteyn Wim , Van Bocxlaer Jan F. 
Published: September 2006

AbstractThe work presented here deals with the development of a quantitative tool for the simultaneous determination of sulfamethoxypyrazine (sulfalene)/pyrimethamine in plasma. The chromatography used only takes 12.5 min, allowing a fast sample turnover time. Relative standard deviation of retention times was never above 3.48% (n=66). Adequate sample clean‐up was achieved by a simple and relatively fast liquid/liquid extraction. In this way, ionisation suppression effects, typical for more simple sample clean‐up procedures, could be avoided resulting in absolute plasma effects of maximum –17.1% for sulfalene, –16.1 for the internal standard (IS), and 12% for pyrimethamine. For both pyrimethamine and sulfalene, quadratic calibration curves from 0.00101 to 0.807 µg/mL for pyrimethamine and from 0.271 to 216 µg/mL for sulfalene gave the best fit. Mean coefficients of determination (R2) were 0.9951 (n=6, CV% 0.39) for pyrimethamine and 0.9942 (n=6, CV% 0.13) for sulfalene. Precision was below 9.35% for pyrimethamine and 13.9% for sulfalene. Inaccuracy remained below 15% at all cases. The optimised method was used for a time‐course study of the sulfalene/pyrimethamine combination concentration in plasma of patients treated with Co‐Arinate®, a new curative antimalaria‐medicine. Copyright © 2006 John Wiley & Sons, Ltd.
Prenatal ultrasonographic prediction of the umbilical coiling index at birth and adverse pregnancy outcome
Authors: De Laat M. W. M. , Franx A. , Nikkels P. G. J. , Visser G. H. A. 
Published: September 2006

AbstractObjectivesTo evaluate whether the antenatal umbilical coiling index (aUCI) as measured by ultrasonography predicts the postnatal umbilical coiling index (pUCI) and adverse pregnancy outcome.MethodsIn a prospective study in 117 pregnancies, the aUCI was measured between 28 weeks and term by ultrasonography. The aUCI was calculated as the reciprocal value of the mean pitch of one complete coil. The pUCI was calculated as the number of coils divided by the cord length in cm. The correlation between aUCI and pUCI was assessed and likelihood ratios for adverse pregnancy outcome were calculated.ResultsWe had complete data on 81 subjects. Mean aUCI ± SD was 0.30 ± 0.09 and mean pUCI ± SD was 0.17 ± 0.08. The correlation coefficient between aUCI and pUCI was 0.66, P < 0.001. Limits of agreement were 0–0.28 coils/cm. The positive likelihood ratio for small‐for‐gestational‐age infants was 2.6 (95% confidence interval (CI) 0.6–11.6) for ultrasound hypocoiling, and 5.7 (95% CI 1.3–24.8) for ultrasound hypercoiling. The positive likelihood ratio for interventional delivery for non‐reassuring fetal status was 1.2 (95% CI 0.2–9.0) for ultrasound hypocoiling, and 10.3 (95% CI 2.1–50.2) for ultrasound hypercoiling.ConclusionsStrong correlation coefficients comparing the aUCI and pUCI do not reflect agreement. Since the limits of agreement were almost as wide as the full range for the pUCI, the aUCI does not predict the pUCI with sufficient precision. Larger prospective studies are required to confirm the predictive potential of the aUCI for adverse pregnancy outcome. Copyright © 2006 ISUOG. Published by John Wiley & Sons, Ltd.
Determining chorionicity in twin gestations: three‐dimensional (3D) multiplanar sonographic measurement of intra‐amniotic membrane thickness
Authors: Senat M.‐V. , Quarello E. , Levaillant J. M. , Buonumano A. , Boulvain M. , Frydman R. 
Published: September 2006

AbstractObjectivesMeasuring the thickness of the membranes to determine chorionicity in twins using two‐dimensional (2D) ultrasound may provide uncertain results, given the possibility of measuring in an oblique view. We aimed to determine whether chorionicity can be assessed during the second and third trimesters by measuring the thickness of the membranes with three‐dimensional (3D) multiplanar ultrasound, which ensures the measurement is perpendicular to the membranes, and to evaluate the reproducibility of the technique.MethodsThis was a prospective study of 84 twin pregnancies (30 monochorionic and 54 dichorionic) between 20 and 35 weeks of gestation. The dividing membranes between the fetuses were visualized with 2D and 3D transabdominal sonography and the thickness of the membranes was measured by the multiplanar technique. Intraobserver variability was assessed by comparing the measurements obtained in sagittal and axial views by the same observer. We examined the frequency distributions to determine the optimal cut‐off point of the thickness of the membranes to predict chorionicity. Kappa index, intraclass correlation coefficients and 95% limits of agreement were calculated to evaluate the inter‐ and intraoperator variability. We also compared membrane‐thickness measurement, during the second and third trimesters, using 2D and 3D ultrasound.ResultsIn monochorionic and dichorionic pregnancies, respectively, the mean thickness was 1.42 (SD, 0.31) mm and 2.48 (SD, 0.47) mm. With 3D ultrasound, the intraclass correlation coefficient was 0.99 in all cases. The 95% limits of agreement were all within ±0.2 mm. The best cut‐off for membrane thickness for discriminating monochorionic from dichorionic twinning was 1.8 mm. Using this cut‐off, there were one false‐negative (sensitivity, 97%; 95% CI, 83–99%) and three false‐positive (specificity, 94%; 95% CI, 85–99%) diagnoses of monochorionic twins. Kappa indices for intra‐ and interoperator variability were all above 90%, suggesting almost perfect agreement. Measurements with 2D sonography were less accurate (sensitivity and specificity, 83%).ConclusionPrenatal assessment of dividing membranes using 3D multiplanar ultrasound is reproducible and may be a useful alternative method for determining chorionicity in twin pregnancies during the second and third trimesters. Copyright © 2006 ISUOG. Published by John Wiley & Sons, Ltd.