Violet-light spontaneous and stimulated emission from ultrathin In-rich InGaN/GaN multiple quantum wells grown by metalorganic chemical vapor deposition

We investigated the spontaneous and stimulated emission properties of violet-light-emitting ultrathin In-rich InGaN/GaN multiple quantum wells (MQWs) with indium content of 60%-70%. The Stokes shift was smaller than that of In-poor InGaN MQWs, and the emission peak position at 3.196 eV was kept constant with increasing pumping power, indicating negligible quantum confined Stark effect in ultrathin In-rich InGaN MQWs despite of high indium content. Optically pumped stimulated emission performed at room temperature was observed at 3.21 eV, the high-energy side of spontaneous emission, when the pumping power density exceeds ???31 kW/ cm2.open6

DETERMINATION OF OPTIMAL LOCATIONS OF AMPHIBIAN ECO-DUCTS BY USING GENETIC ALGORITHMS: A CASE STUDY OF ODAESAN NATIONAL PARK IN KOREA

There are currently no systematic guidelines for placing the animal passes for wildlife to cross safely the human-made roads. This study presents a mathematical model that determines the optimal locations for amphibian eco-ducts by using a genetic algorithm. The study area is route no. 6 of Odaesan National Park in Korea, and the animals of focus are amphibians. The most crucial factor, the migration distance between amphibian road-kill sites and proposed eco-duct sites, was considered for determination of the optimal locations of amphibian eco-ducts. They were determined by calculating the minimum total distances associated with this factor near the road-kill sites. The model determined 69 optimal locations of ecoduct sites in eight sections of route no.6

Pyridoxine induced neuropathy by subcutaneous administration in dogs

To construct a sensory neuropathy model, excess pyridoxine (150 mg/kg s.i.d.) was injected subcutaneously in dogs over a period of 7 days. During the administrations period, the dogs experienced body weight reduction and proprioceptive loss involving the hindquarters. After pyridoxine administration was completed, electrophysiological recordings showed that the M wave remained at a normal state, but the H-reflex of the treated dogs disappeared at 7 days. The dorsal funiculus of L4 was disrupted irregularly in the axons and myelin with vacuolation. The dorsal root ganglia of L4, and sciatic and tibial nerves showed degenerative changes and vacuolation. However, the lateral and ventral funiculi of L4 showed a normal histopathologic pattern. Although this subcutaneous administration method did not cause systemic toxicity and effectively induced sensory neuropathy, this study confirmed the possibility of producing a pyridoxine-induced sensory neuropathy model in dogs with short-term administration

Feasibility of Ivy (Hedra helix) for landscaping in Seoul, Korea

Due to the global warming, Seoul in Korea seems to be plausible to grow evergreen broad-leaved trees over the cold winter. This offers the planting options to create green environment. Thus, it became worth investigating what kinds of evergreen broad-leaved plants could stand in Seoul during the winter. Ivy (Hedera helix) has been chosen in the current study which is a well-known native and ornamental plant in Europe. It grows in warm condition in general. The current study tracked H. helix which is evergreen cover plant over winter in order to evaluate the possibility for utilizing this species as a climber or cover-plant in Seoul. We found that H. helix can survive over the winter and can be utilized to create evergreen environment in Seoul. It also implies that similar kinds of plants could be tested assuming the environment of Seoul is becoming more suitable for the plants originated from the warmer sites. H. helix is an option for elaborating outdoor environments in the city that lacks of green color

EFFECTS OF THREE PREPARATORY MOVEMENTS ON SIDEWARD PROPULSIVE MOVEMENT

This study investigated the effects of three preparatory movements (squat, countermovement and hopping) on the sideward propulsive movement. Seven subjects were analyzed in 3-D to determine how fast they reacted to external signals, using three techniques, to reacl1 an aIming spot. The hopping and the countermovement types were considered better than the squat type in the propulsion. The hopping particularly showed the shortest duration from the external signal to take-off and also recorded high extension moments due to the pre-stretch mechanism for the push-off phase