6-Pentyl-2H-pyran-2-one: A Potent Peach-Derived Kairomone for New Zealand Flower Thrips,Thrips obscuratus

New Zealand flower thrips, Thrips obscuratus (Thysanoptera: Thripidae), are attracted to ripening fruits, especially peaches. Volatiles from unripe and ripe peach fruits were collected and analyzed by gas chromatography/mass spectrometry. Six lactones were found only in ripe peach volatiles: γ-heptalactone, γ-octalactone, γ-nonalactone, 6-pentyl-2H-pyran-2-one, γ-decalactone, and δ-decalactone. When these compounds were tested individually in field-trapping experiments, three of them (γ-octalactone, γ-nonalactone, and 6-pentyl-2H-pyran-2-one) attracted New Zealand flower thrips. In another field-trapping experiment, aimed at testing various combinations of the three active compounds, no synergistic effects were found among all combinations tested; no combination caught more thrips than 6-pentyl-2H-pyran-2-one, alone. A further field-trapping experiment was conducted to determine the dose (10, 100, and 500 mg) of 6-pentyl-2H-pyran-2-one that gave the greatest catch of T. obscuratus, while also comparing it against another attractant, ethyl nicotinate, for T. obscuratus. The greatest catches in traps baited with either attractant were at loadings of 500 mg. At both 10 and 500 mg, traps baited with 6-pentyl-2H-pyran-2-one caught more T. obscuratus than those baited with the same amounts of ethyl nicotinate. 6-Pentyl-2H-pyran-2-one is a potent attractant for New Zealand flower thrips and, therefore, could be used for monitoring and control of New Zealand flower thrips. Work is underway developing monitoring and control options utilizing 6-pentyl-2H-pyran-2-one for this important pest.     

Flux measurements for a DD neutron generator using neutron activation analysis

The fast and maximum thermal neutron fluxes from the DD-109 neutron generator at the University of Sharjah were experimentally measured by the activation technique using different neutron reactions. The thermal and fast neutron fluxes were found to be 2.960 × 10~6 and6.186 × 10~7 n/cm~2 s, respectively. This was done to verify the modeling results for the optimum moderator thickness needed to maximize the thermal neutron flux. The optimum moderator thickness was found to be between 3.5 and4 cm. The present data were compared with the detailed MCNP model-based calculation performed in earlier work to simulate the generator.     

A suggested new profile for externally pressurized power screws

In general, the traditional types of power screws may be considered as ordinary screw threads with certain dimensional restrictions recommended to improve their dry working performance. However, when applying the theory of externally pressurized lubrication to such machine elements, it may be inconvenient to confine the study to such constraints. The problem is investigated considering the general form of the screw thread; the optimum combination of the thread parameters for the most suitable externally pressurized power screw are determined.A new profile for externally pressurized power screws is suggested and proved to be more convenient and efficient than the ordinary profiles.     

Individual differences, exercise and leisure activity in predicting affective well-being in young adults

This study focuses on the prevalence of exercise and health-related leisure activities (smoking, drinking), across groups of subjects, defined by personality and gender, in relation to subjective well-being. Results from a cross-sectional survey of 187 participants are reported. Males (n = 80) reported more drinking (p < 0.001) and smoking (p < 0.001) than females, though they also reported higher habitual physical activity levels (p < 0.001). Females (n = 107) reported more frequent use of social support coping (p < 0.01). There was a positive association between extraversion and self-reported habitual physical activity as well as alcohol consumption (even when controlling for gender). Neuroticism was not related to any of the exercise and leisure activity variables. Multiple regression analyses predicted 34% of variance for the depression-enthusiasm and 39% of the variance for the anxiety-contentment measures of affective well-being. Neuroticism (p < 0.001) and avoidance coping (p < 0.05) were the only significant predictors of both anxiety-contentment and depression-enthusiasm. It is concluded that the influence of individual differences such as personality and gender on coping behaviour and well-being is consistent with social learning theory research. Limitations of cross-sectional research designs necessitate caution with inferring causal paths. Recommendations for future research are presented concerning the use and value of repeated measures designs within research into exercise and well-being.     

Temperature dependence of the electrical conductivity in 4, 4′ bis(2-thenylideneamino)biphenyl and 4, 4′ bis(thenyldiphenyl-phosphinylmethyleneamino)biphenyl compounds

Correlation of the molecular structure and utilizing measurements of the electrical conductivity, activation energy of conduction of 4,4 bis(2-thenylideneamino)biphenyl (SB) and 4,4 bis(thenyl-diphenylphosphinylmethyleneamino)biphenyl (OPSB) compounds have been carried out. The results of the activation energies, obtained from the electrical conductivity measurements, as well as the energy gaps calculated from ultraviolet (u.v.) and visible spectra in the solid state indicate that the investigated compounds behave like semiconducting materials. The delocalized -electrons in addition to the lone pairs of electrons on the nitrogen atoms of the two compounds as well as the donor effect of diphenylphosphinyl groups of OPSB compound were considered as the main sources participating in the conduction processes.     

Characterization of short-range order in an amorphous Cd–Se–Te system by wide angle X-ray scattering(WAXS)

Short-range orders of Cd_xSe_70−xTe₃₀ amorphous alloys of a chalcogenide system with 2≤x≤10 have been studied by wide-angle X-ray scattering (WAXS). Once the hypotheses on the local order of the alloy had been formulated, the radial distribution function (RDF) analysis have make it possible to evaluate them referring specifically to the coordination of the atoms. The structural parameters such as atomic distance between the different possible pairs of atoms in each element J(r), the structure factor F(q), the pair distribution function G(r) and the coordination numbers for amorphous samples have been discussed. Moreover, in our system, under study, the average coordination numbers of the three different atoms involved and their distance to the first coordination sphere have been determined. However, the extraction of the inverse Fourier transforms to generated atomic distribution function has led us to a simulated reduced interference function Q(q).     

Kinetics of initial stage of sintering of UO2 and UO2 with Nd2O3 addition

The kinetics of initial stage sintering of UO₂ powder were reinvestigated, using Ar-10% H₂ atmosphere. The effect of the addition of neodynium oxide was studied. The results revealed that surface and grain boundary diffusion mechanisms act simultaneously. The values of activation energies were found to be $\text{48.48 ± 3.51 kcal/mole}$ in the temperature range 870–942°C and $\text{89.88 ± 9.87 kcal/mole}$ in the temperature range of 942–1030°C for UO₂, and $\text{115.61 ± 7.77 kcal/mole}$ in the temperature range 1030–1150°C for UO₂ + Nd₂O₃. An important decrease in the calculated diffusion coefficient occurs by the addition of Nd₂O₃.     

Radiation-induced oxidative degradation of poly(vinyl chloride)

Gas evolution and oxygen consumption in the γ-irradiation of PVC were studied. The gas evolution and the oxidative degradation are retarded by the presence of plasticizers and stabilizers. The G(HCI) and G(H₂) and 8 and 0.24 for the irradiation of pure PVC under vacuum and 0.02 and 0.14 for that of plasticized PVC, respectively. Gas evolution increases in the presence of oxygen, specially for the pure PVC. The G(–O₂) values for the pure and plasticized PVC are 30 and 12, respectively. The dependence of gas evolution and oxygen consumption on the oxygen pressure is more pronounced for the plasticized PVC than pure PVC because the oxygen diffusion is controlled.     

Disposition of the flavonoid quercetin in rats after single intravenous and oral doses

The pharmacokinetic and mean time tissue distribution parameters, after a single 50-mg/kg dose of quercetin administered as intravenous bolus, oral solution, and oral suspension, were determined using rat as an animal model. Following intravenous administration, the elimination rate constant and the elimination half-life were found to be 0.0062 min^-1 and 111 min, respectively. Examining the mean time tissue distribution parameters reflected a strong binding affinity of the drug molecules to both plasma and tissue proteins. In addition, the low permeability rate of drug molecules in the peripheral system was demonstrated. Following the oral administration of the drug, the extent of absorption was greater from solution than from suspension. Moreover, the solution showed a shorter T_max and a higher C_max than suspension. The absolute bioavailability for the solution was 0.275 and that for suspension was 0.162. The mean residence time (MRT) and the mean absorption time (MAT) were higher for suspension, reflecting the need for dissolving the drug in order to be absorbed. The mean (in-vivo) dissolution time (MDT_in-vivo) was 34.5 min. Thus, an oral quercetin formulation that can readily form a drug solution in the gastrointestinal tract may enhance the absorption of the drug.     

Quantitative analysis of the effects of ultrasound from an odor sprayer on moth flight behavior

A piezoelectric sprayer was recently developed for precision release of odor stimuli in olfactory research. The device replaces conventional dispensers used to release semiochemicals in studies of moth flight toward odor sources. However, the device generates high-frequency sounds in the range that some moths can hear. Ultrasound from the standard set-up sprayer had a considerable impact on flight behavior of the silver Y moth, Autographa gamma, tested in a flight tunnel. It was affected at all behavioral stages when the dispenser was driven at 120 kHz. Only 5% of the moths reached the source when exposed to 120-kHz sound from the dispenser compared to 65% in the control group without sound. The proportion taking flight was also reduced. Hearing threshold curves obtained electrophysiologically revealed that moths were sensitive to the frequency range at which the sprayer was operated and that sound intensity from the sprayer was up to 40 dB above the moths' electrophysiological hearing threshold. The audiogram for A. gamma was similar to audiograms obtained for other noctuids. Hearing sensitivity was highest at around 15 kHz, where the threshold was 35 dB SPL (sound pressure level). The threshold increased with frequency up to 94 dB SPL at 160 kHz. We improved the sprayer to operate at 300 kHz, which is beyond the hearing ability of most insects with ears. At this high frequency, the moths' sensitivity to ultrasound is reduced considerably, and we did not observe any effect on flight behavior compared to a control group without sound. Accordingly, this new piezoelectric sprayer can be used with ultrasound-sensitive insects and insensitive insects alike.