This study examined the subacute oral toxicity of Dendropanax morbiferus H.Lév leaves hot-water extracts (DMWE) using male and female Spargue-Dawley rats. Rats were orally administered the DMWE at dose levels of 0, 250, 500, 1,000, and 2,000 mg/kg body weight (BW) for four weeks. For experimental period, clinical signs and the number of deaths were examined, and feed intake and BW of all experimental animals were measured once a week for four weeks. At the end of the experiment, blood samples were collected from all rats, and all animals were euthanized and autopsies were performed to collect major organs. No dead animals were found during the experimental period. In addition, no differences were found between control and DMWE-treated groups in feed intakes, BW changes, organ weights, clinical signs, hematological parameters, and serum biochemical parameters. The results of this study provided evidence that oral administration of DMWE at the dose of 2,000 mg/kg BW is safe in rats and may not exert severe toxic effects.

In this study, the acute toxicity of Dendropanax morbiferus H.Lév leaf hot-water extracts (DMWE) was examined in male and female ICR mice. Mice were orally administered the DMWE at dose levels of 0, 250, 500, 1,000 and 2,000 mg/kg body weight (BW) for single-dose toxicity test. There were no significant differences in change of BW between control and all DMWE treated-groups. In hematological and blood biochemical analysis, none of the parameters were affected by the DMWE. Similarly, there were no significant effects on markers for liver and kidney functions in all DMWE treated-groups. Since there were no adverse effects of the DMWE in single oral toxicity tests, even at the highest doses, it was concluded that the lethal dose 50 (LD50) of DMWE is estimated at > 2,000 mg/kg BW.

Despite the increasing interest in Deep Borehole Disposal (DBD) for its capability of minimizing disposal area, detailed research about DBD operation system design should be conducted before the DBD can be implemented. Recently, DBD operation system applying wireline emplacement (WE) technique is under study due to its high flexibility and capability of minimizing surface equipment. In this study, a conceptual WE system, and operation procdure is introduced. The conceptual WE system consists of 3 main stations, which from the top are hoisting station (HS), canister connection station (CCS) and basement (BS). In HS, WE is controlled and monitored. The WE is controlled using wireline drum winch and sheaves, and load on wireline is measured using a load cell. HS also has a pressure control system (PCS), which monitors internal pressure of the system, and a lubricator, which act as housing for joint device, allowing the joint device to be easily inserted into the borehole. The joint device is used to connect the disposal canister to wireline for emplacement/retrieval. In CCS, a rail transporter brings a transport cask containing disposal canisters, then the transport cask is connected to the hoisting system and a PCS in the BS. The main component located at canister station are a sliding shielding door (SSD), and a slip. The SSD is used to prevent canister from falling into borehole during the connecting operation and prevent radiation from BS to affect the workers. The slip is located beneath the SSD and is used to hold the disposal canister before it is lowered into the borehole. In BS, PCS is installed to prevent overflow and blowout of borehole fluid. The PCS consists of wireline pressure valve, christmas tree and BOP, which all are a type of pressure valve to seal the borehole and release pressure inside the borehole. The WE procedure starts with transporting transport cask to CCS. The transport cask is connected to lubricator, and PCS. Joint device is lowered down to be connected with disposal canisters, then pulled up to check the load on the wireline. After the check-up, SSD is opened, and disposal canister is lowered into the borehole. When desired depth is reached, joint device is disconnected and retrieved for next emplacement. In this study, the conceptual deep borehole disposal system design implementing WE technique is introduced. Based on this study, further detailed design could be derived in future, and feasibility could be tested.

Natural environmental resources are considered a prospective source of microorganisms capable of producing biocatalysts with great potential in industrial areas. Arable soil fertilized with peat moss is a habitat for various microorganisms. The present research focused on the isolation and identification of hydrolase-producing bacteria that thrive at a broad temperature range. In this study, a total of 33 strains were isolated from arable soil fertilized with peat moss (Silla Garden in Busan, South Korea). The isolated bacteria were mesophiles and thermophiles with a wide temperature range. Taxonomic identification showed that the isolated strains belonged to 2 phyla, 5 families, 10 genera, and 24 species. Subsequently, the isolated strains were screened for hydrolase (amylase, lipase, and protease) activity. All isolates possessed activity of at least one enzyme and six bacterial isolates produced combined extracellular enzymes. Diversity of soil bacteria species in the present study suggest the potential of soil bacteria in the various industrial applications.

Admirandus multicavus Belogurov and Belogurova, 1979, a new record of free-living marine nematode species belonging to family Oncholaimidae is reported based on the specimens collected from the intertidal sediments of Korea. Admirandus multicavus is characterized by the following unique characteristics: cephalic setae (1-2 μm long), spicules (71-126 μm long) and gubernaculum (15-31 μm long), midventral preanal supplementary organ, three glandular duct openings of the Demanian system, and stoma length measuring twice the width. A comparative analysis of the biogeographical and ecological characteristics of Admirandus species is presented. DIC (Differential interference contrast) photomicrographs of the species are also provided herein. This report represents the first taxonomic analysis of the genus Admirandus Belogurov and Belogurova, 1979 discovered from the Korean seawaters.