Response of Mythimna unipuncta Males to Components of the Sesamia nonagrioides Pheromone

Several sympatric lepidopteran species feed on maize plants, and the different components of their species-specific female sex pheromones may play a role in attracting conspecifics and/or deter heterospecific males. In this study, we analyzed the content of Mythimna unipuncta pheromone glands and tested the response of males to components of their own pheromone blend and that of Sesamia nonagrioides in the wind tunnel. Whole pheromone glands, and lures where (Z)-9-hexadecenyl acetate, Z)-11-hexadecen-1-ol or (Z)-9-hexadecenyl acetate + (Z)-11-hexadecen-1-ol were added to the major component, (Z)-11-hexadecenyl acetate, elicited significantly higher responses by M. unipuncta males than lures with main component alone, although the levels varied with concentration. In the field a rather different outcome was observed, as the addition of other compounds found in the female pheromone gland did not improve trap catch over lures with only (Z)-11-hexadecenyl acetate. The addition of (Z)-11-hexadecenal, a compound of the S. nonagrioides pheromone, to (Z)-11-hexadecenyl acetate significantly reduced attraction of M. unipuncta males both in the wind tunnel and in the field, as well as the number of sympatric clover cutworm, Discestra trifolii, under field conditions. The addition of (Z)-9-hexadecenyl acetate, a minor component of the M. unipuncta pheromone blend, reduced the number of S. nonagrioides captured in field traps that were baited with the S. nonagrioides lure. The significance of such inhibition in the reproductive isolation of sympatric species that attack maize is discussed.     

Experimental Design in the Optimization of a Microwave Acid Digestion Procedure of Biomorphic Ceramic Based on ZrO2

Abstract

The present work deals with the manufacturing of biomorphous ZrO₂-ceramics from oak wood as biological template structure. Oak wood was vacuum infiltrated with zirconia-sol. Subsequent pyrolysis in inert atmosphere at 800°C and annealing in air up to 1550°C resulted in the formation of porous, microcellular ZrO₂-ceramics. After the material characterization, we optimized the sample dissolution by acid attack in an oven under microwave irradiation. Experimental designs were used as a multivariate strategy for the effects evaluation of varying several variables. The optimization was performed using full factorial design 2⁴. Four variables (time, power, volume of HNO₃, and volume of HF) were considered as factors and as response the concentration of different metal ions in the optimization process.     

4 Gbit/s GaAs MESFET laser-driver IC

A high-speed laser-driver IC has been fabricated using etched-gate enhancement/depletion-mode MESFET technology. It has been demonstrated that the device is capable of driving 25? load with 80 mA modulation current at up to 4 Gbit/s NRZ data rate.     

A software for optical characterization of thin films for microelectronic applications

We present a software for the optical characterization of thin films using spectrophotometric and/or ellipsometric measurements. The program allows the analysis of a wide range of multi-layered structures, either with respect to the composition, microstructure or thickness of any of the layers.     

Sterile Filtration of NanoCrystal™ Drug Formulations

A Nano Crystal^TM dispersion of the iodinated x-ray contrast agent iodipamide was prepared by wet milling the drug substance in the presence of Pluronic® F127 stabilizer. The mean particle size of the formulation was 98 nm and all drug particles in the formulation were smaller than 220 nm as determined by dynamic light scattering. Approximately 1 liter of dispersion was filtered through a sterile 0.2-μm disposable capsule filter (Supor® 200 DCF^TM, 0.I m² effective filtration area [EFA], Gelman Sciences) to condition the capsule. No drug concentration or size distribution changes were detected after the filtration process. The microbiological validation tests were performed using Pseudomonas diminuta organisms to challenge the capsule under simulated worst-case process conditions. The results showed that the Supor 200 DCF was able to retain 100% Pseudomonas diminuta organisms (≥10⁷ organisms per cm² of effective filtration area). Thus, this study demonstrated that terminal filtration is a feasible process to sterilize Nano Crystal^TM drug dispersions that may be chemically or physically unstable at elevated temperatures and thus not amenable to terminal heat sterilization.     

Graded-index-rod external coupled-cavity laser with backface output-monitor-stabilized single-frequency operation

We have demonstrated a graded-index-rod external coupled-cavity (GRECC) laser with backface output through a partially transmitting external cavity mirror. Laser output is monitored from the backface in a transmitter module with double-loop feedback control which stabilizes output power and maintains single-frequency operation under CW and pseudorandom pulse modulation.     

Interfacial polymerization of an epoxy resin and carboxylic acids for the synthesis of microcapsules

BACKGROUND: Microencapsulation technology promises new applications such as intelligent microstructures, phase change materials and self‐healing composites. Microcapsule synthesis and characterization have been researched extensively; however, the well‐known polymerization between epoxy resins and carboxylic acids has not been used to prepare microcapsules. RESULTS: Microcapsules were prepared by interfacial polymerization of an oil‐in‐water emulsion which contained a commercial epoxy resin and multifunctional carboxylic acids. The microcapsules obtained were characterized using optical microscopy and scanning electron microscopy. Experiments performed at lower stirring rates led to larger microcapsules, in the range 100–400 µm, while higher stirring rates resulted in microcapsules in the range 10–50 µm. CONCLUSIONS: Microcapsules can be prepared by interfacial polymerization of epoxy resins, an extensively studied and widely used class of polymers. By means of NMR characterization we gained insight into the mechanism of polymerization at the interface wherein products coming from the more hindered ring opening as well as from intermolecular transesterification are identified. The presence of a crosslinker affects the morphology of the external microcapsule surface. Copyright © 2008 Society of Chemical Industry     

Building phonotactic knowledge in bilinguals: Role of early exposure.

Timing and amount of exposure to a 2nd language in the acquisition of phonotactic restrictions was examined in 4 experiments. In Experiments 1 and 2, 10-month-old monolingual and bilingual Catalan-Spanish infants were presented with nonwords that were phonotactically legal or illegal in Catalan and phonotactically illegal in Spanish. Differences between the 4 groups of infants were obtained as a function of language dominance. In Experiments 3 and 4, adult Spanish-Catalan bilinguals were compared with the same materials. Catalan-dominant bilinguals were more accurate than Spanish-dominant bilinguals in their perception of legal sequences; however, they were not more accurate with illegal sequences. The findings suggest a complex correlation between the pattern of preference and the amount and timing of exposure. (PsycINFO Database Record (c) 2010 APA, all rights reserved)