Combination of UV and green light synergistically enhances the attractiveness of light to green stink bugs Nezara spp.

The southern green stink bug Nezara viridula and its congener N. antennata are important agricultural pests worldwide. These species show positive phototaxis and their compound eyes have high sensitivity to UV and green lights. The attractiveness of monochromatic UV, green lights and combined UV and green light to stink bugs was investigated under field conditions. The number of stink bugs caught increased with the number of UV LEDs, but very few bugs were caught using green light, irrespective of the number of LEDs. However, the most stink bugs were caught when both colors were combined. These results indicate that monochromatic green light is less attractive to Nezara bugs, but when mixed with UV light, it synergistically enhances the attractiveness of UV light. This finding contributes to the construction of reliable and highly specific light traps to monitor Nezara bugs. The addition of green light hardly affected the attractiveness of the UV light to other insects, such as Anomala beetles, which are often caught in light traps. We conclude that the spectral composition of light that is attractive to nocturnal insects depends on the species, hence it is possible to make ecologically friendly light traps that are target specific.

Effect of water impurity in CsLiB6O10 crystals on bulk laser-induced damage threshold and transmittance in the ultraviolet region.

We investigate the effect of water impurity in a CsLiB(6)O(10) (CLBO) crystal on the ultraviolet properties of the bulk laser-induced damage threshold (LIDT) and transmittance. The water impurity was eliminated by heating the CLBO sample with dimensions of 5 mm x 5 mm x 10 mm at 150 degrees C in an ambient atmosphere and subsequently in a dry atmosphere. The bulk LIDT of the sample after heat treatment improved by about 1.6-fold compared with that before heat treatment.

[Massive subcutaneous emphysema following percutaneous tracheostomy].

Although percutaneous dilatational tracheostomy (PDT) is fast becoming the method of choice for securing an airway in chronic ventilated patients in an intensive care unit (ICU). Subcutaneous emphysema is an unusual and sometimes lethal complication which may extend the length of stay in the ICU. We report a case of massive subcutaneous emphysema without tracheal wall laceration that occurred in the ICU after PDT. An 81-year-old woman was admitted to our ICU due to infective exacerbation of chronic obstructive airways disease. Her medical therapy included nebulized bronchodilators, steroids and empirical antibiotics. Within thirty-six hours of initial endotracheal intubation PDT was performed. Several hours following the procedure, the patient developed massive subcutaneous emphysema encompassing her entire body. No pneumothorax was identified on subsequent chest X-ray. Laryngoscopic and bronchoscopic examination showed no evidence of tracheal wall laceration. We discuss the etiology and management plan for this rare complication.

Biosynthesis of linoleic acid in Tyrophagus mites (Acarina: Acaridae).

We report here that Tyrophagus similis and Tyrophagus putrescentiae (Astigmata: Acaridae) have the ability to biosynthesize linoleic acid [(9Z, 12Z)-9, 12-octadecadienoic acid] via a Δ12-desaturation step, although animals in general and vertebrates in particular appear to lack this ability. When the mites were fed on dried yeast enriched with d31-hexadecanoic acid (16:0), d27-octadecadienoic acid (18:2), produced from d31-hexadecanoic acid through elongation and desaturation reactions, was identified as a major fatty acid component of phosphatidylcholines (PCs) and phosphatidylethanolamines (PEs) in the mites. The double bond position of d27-octadecadienoic acid (18:2) of PCs and PEs was determined to be 9 and 12, respectively by dimethyldisulfide (DMDS) derivatization. Furthermore, the GC/MS retention time of methyl 9, 12-octadecadienoate obtained from mite extracts agreed well with those of authentic linoleic acid methyl ester. It is still unclear whether the mites themselves or symbiotic microorganisms are responsible for inserting a double bond into the Δ12 position of octadecanoic acid. However, we present here the unique metabolism of fatty acids in the mites.

Effects of polymer structure on properties of sulfonated polyimide/protic ionic liquid composite membranes for nonhumidified fuel cell applications.

To investigate the effects of polymer structure on the properties of composite membranes including a protic ionic liquid, [dema][TfO] (diethylmethylammonium trifluoromethanesulfonate), for nonhumidified fuel cell applications, we synthesized sulfonated polyimides (SPIs) with different structures as matrix polymers, which have different magnitudes of ion-exchange capacities (IECs), different sequence distributions of ionic groups, and positions of sulfonate groups in the main chain or side chain. Despite having similar IECs, multiblock copolymer SPI and random copolymer SPI having sulfonate groups in the side chain exhibit higher ionic conductivity than random copolymer SPI having sulfonate groups in the main chain, indicating that the flexibility of sulfonic acid groups and the sequence distribution of ionic groups greatly affect the ion conduction. Atomic force microscopy observation revealed that the multiblock copolymer SPI forms more developed phase separation than the others. These results indicate that the flexibility of sulfonic acid groups and the connectivity of the ion conduction channel, which greatly depends on the sequence distribution, affect the ion conduction.

Improved efficiency of a pulsed optical parametric oscillator by delayed double-pass pump.

By delaying the second pass of the pump of a singly resonant optical parametric oscillator, the conversion efficiency can be improved. We show the experimental results of an intracavity-doubled singly resonant parametric oscillator pumped by a Q-switched laser. Using 0.49 mJ of pump energy at 532 nm from a diode-pumped Nd:YAG laser, 0.085 mJ of 488 nm was obtained with the optimum delay for the second pass of the pump, giving a conversion efficiency of 17%. The improvement over the case of a single-pass pump was 85%, and the improvement over the double-pass pump with a small delay was 40%.

Continuous-wave all-solid-state 244 nm deep-ultraviolet laser source by fourth-harmonic generation of an optically pumped semiconductor laser using CsLiB6O10 in an external resonator.

We report an all-solid-state laser system that generates over 200 mW cw at 244 nm. An optically pumped semiconductor laser is internally frequency doubled to 488 nm. The 488 nm output is coupled to an external resonator, where it is converted to 244 nm using a CsLiB(6)O(10) (CLBO) crystal. The output power is limited by the available power at 488 nm, and no noticeable degradation in output power was observed over a period of several hours.