• The Bulletin of The Korean Astronomical Society
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• v.44 no.2
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• pp.37.3-37.3
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• 2019

We study the stellar populations of the brightest group galaxies (BGGs) in groups whose halos have different dynamical states, using observational data from the GAMA survey. The two independent indicators to probe the dynamical state of the halo are the magnitude gap between two most luminous galaxies (∆M12) and offset between BGG and the luminosity center (Doffset) of the group. Such indicators complement each other in identifying relaxed and unrelaxed galaxy groups in our samples. We find that the BGGs of unrelaxed groups have significantly bluer NUV-r colours than in relaxed groups. This is also true at fixed sersic index. We find the bluer colours cannot be explained away by differing dust fraction, suggesting there are real differences in their stellar populations. SFRs derived from SED-fitting tend to be higher in unrelaxed systems. This could be partly because there is a greater fraction of BGGs with non-elliptical morphology, but also because unrelaxed systems are expected to have larger numbers of mergers, some of which may bring fuel for star formation. The SED-fitted stellar metallicities of BGGs in unrelaxed systems also tend to be higher, perhaps because the building blocks of the unrelaxed systems were more massive and had more time to enrich themselves. We find that the ∆M12 parameter is the most important parameter behind the observed differences in the relaxed/unrelaxed groups. We also find that groups selected to be unrelaxed using our criteria tend to have higher velocity offsets between the BGG and their group.

• Korean journal of applied entomology
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• v.47 no.3
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• pp.273-286
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• 2008

Road-map for the environmental friendly integrated pest management(IPM) of insect pests was drawn up on the strawberry vinyl-houses of farmer's field. Major insect pests were occurred Tetranychus urticae and Aphis gossypii during the strawberry plant seeding in the vinyl house and open field. Also, same insect pests were occurred in the vinyl house during harvesting season of strawberry. For the control of T. urticae and A. gossypii, Phytoseiulus persimilis and Aphidius colemani as natural enemies were input to the vinyl house, respectively. However, because these natural enemies could not control insect pest populations, acaricide and insecticide were sprayed. Then natural enemies were input again in the vinyl house. Natural enemies could not endure the intense cold and differences of temperature and relative humidity between day and night during strawberry harvesting season. So, their behavior and control activity of pests were more decrease than pests. Firstly, natural enemies are input in the vinyl house during the early breeding season of strawberry, secondly, acaricides and insecticide are sprayed for the control of mites and aphids, respectively, during the middle breeding season in the hard winter. Finally, natural enemies are re-input in the vinyl house during the middle and late breeding season.

• Korean journal of applied entomology
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• v.48 no.2
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• pp.123-158
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• 2009

An attempt was made to stimulate future research by providing exemplary information, which would integrate published knowledge to solve specific pest problem caused by resistance. This review was directed to find a way for delaying resistance development with consideration of chemical(s) nature, of mixture, rotation, or mosaics, and of insecticide(s) compatible with the biological agents in integrated pest management (IPM). The application frequency, related to the resistance development, was influenced by insecticide activity from potentiation, residual period, and the vulnerability to resistance development of chemical, with secondary pest. Chemical affected feeding, locomotion, flight, mating, and predator avoidance. Insecticides with negative cross-resistance by the difference of target sites and mode of action would be adapted to mixture, rotation and mosaic. Mixtures for delaying resistance depend on each component killing very high percentage of the insects, considering allele dominance, cross-resistance, and immigration and fitness disadvantage. Potential disadvantages associated with mixtures include disruption of biological control, resistance in secondary pests, selecting very resistant population, and extending cross-resistance range. The rotation would use insecticides in high and low doses, or with different metabolic mechanisms. Mosaic apply insecticides to the different sectors of a grid for highly mobile insects, spray unrelated insecticides to sedentary aphids in different areas, or mix plots of insecticide-treated and untreated rows. On the evolution of pest resistance, selectivity and resistance of parasitoids and predator decreased the number of generations in which pesticide treatment is required and they could be complementary to refuges from pesticides To enhance the viability of parasitoids, the terms on the insecticides selectivity and factors affecting to the selectivity in field were examined. For establishment of resistant parasitoid, migration, survivorship, refuge, alternative pesticides were considered. To use parasitoids under the pressure of pesticides, resistant or tolerant parasitoids were tested, collected, and/or selected. A parasitoid parasitized more successfully in the susceptible host than the resistant. Factors affecting to selective toxicity of predator are mixing mineral oil, application method, insecticide contaminated prey, trait of individual insecticide, sub-lethal doses, and the developmental stage of predators. To improve the predator/prey ratio in field, application time, method, and formulation of pesticide, reducing dose rate, using mulches and weeds, multicropping and managing of surroundings are suggested. Plant resistance, predator activity, selective insect growth regulator, and alternative prey positively contributed to the increase of the ratio. Using selective insecticides or insecticide resistant predator controlled its phytophagous prey mites, kept them below an economic level, increased yield, and reduced the spray number and fruits damaged.

• Korean Journal of Microbiology
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• v.48 no.4
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• pp.240-245
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• 2012

Pseudomonas aeruginosa is an opportunistic Gram-negative bacterium that causes serious infection, particularly in immunocompromised patients. Also, P. aeruginosa possessing carbapenem-resistant metallo-${\beta}$-lactamases (MBL) has been reported with increasing frequency in Korea. We therefore analyzed the level of multidrug-resistant clinical P. aeruginosa isolated from a secondary hospital in Korea in 2010. A total of 92 isolates of P. aeruginosa were collected from Sahmyook Medical Center in 2010. Susceptibility to antimicrobial agents was determined by analysis of the minimum inhibitory concentration test; the inhibitor-potentiated disk diffusion (IPD) test was performed for MBL detection. RAPD-PCR was used for genotyping to rapidly characterize P. aeruginosa strains isolated from clinical patients. The percentages of non-susceptible isolates were as follows: 40.2% to ceftazidime, 58.7% to meropenem, 56.5% to gentamicin, 46.7% to tobramycin, 62.0% to ciprofloxacin and 97.8% to chloramphenicol. The 29 multidrug-resistant strains were screened by the IPD test: of the 21 PCR-positive isolates, 19 were IPM-1 producers and 2 were VIM-2 producers. Among the 19 IMP-1-producing P. aeruginosa isolates, 16 isolates showed similar patterns, and three different banding patterns were observed. The proportion of IMP-1-producing multidrug-resistant P. aeruginosa from clinical isolates steadily increased in this secondary hospital in Korea in 2010. This study provides information about the antimicrobial-resistant patterns and genotype of multidrug-resistant P. aeruginosa isolated from clinical isolates in Korea, 2010.

• Korean Journal of Veterinary Research
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• v.44 no.2
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• pp.217-224
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• 2004

This study was carried out to investigate the antibiotic resistance pattern of Listeria spp. and Staphylococcus aureus. A total of 17 (14.8%) L. monocytogenes, 13 (11.3%) L. innocua, 7 (7%) L. welshimeri, and 83 (72.2%) S. aureus were isolated from commercial poultry carcasses in Seoul and Kyonggi province during the period between 2001 and 2003. Antibiotic susceptibility test of all Listeria strains isolated was performed by the disk agar diffusion method. Antibiotics used in the study were as follows; Amikacin (An), Ampicillin (Am), Cephalothin (Cf), Chloramphenicol (C), Ciprofloxacin (Cip), Erythromycin (E), Gentamicin (Gm), Imipenem (Ipm), Kanamycin (K), Minocycline (Mi), Neomycin (N), Norfloxacin (Nor), Ofloxacin (Ofx), Penicillin (P), Streptomycin (S), Tetracycline (Te), Tobramycin (Nn), Trimethoprim (Tmp), Trimethoprim/Sulfamethoxazloe (Sxt), and Vancomycin (Va). The antibiotic resistance pattern of S. aureus isolates was performed by the disk agar diffusion method. For the latter program, antibiotics used to the study were as follows; Cf, C, Cip, Clindamycin (Cc), E, Gm, Ipm, Nafcillin (Nf), Oxacillin (Ox), P, Te, Sxt, and Va. Of the 17 L. monocytogenes isolates, 94.1% were resistant to Te, 88.2% to Mi, 11.8% to Nor, 11.8% to S, 5.9% to Cip, and 5.9% to C. Of 13 L. innocua, 53.8% were resistant to Te, 23.1% to Mi, 23.1% to S, 7.7% to Cip, and 7.7% to Nor. Of 7 L. welshimeri, 57.1% were resistant to Te, and 14.3% to Am. Of 83 S. aureus, 100% were resistant to Te, 86.7% to Gm, 34.9% to P, 15.7% to Cip, 12% to Cc, 9.6% to E. The multiple antibiotic resistance patterns of L. monocytogenes isolates were observed in Te Mi Cip (5.9%), Te Mi Nor (5.9%), Te Mi (76.5%), and Te Nor (5.9%). Multiple antibiotic resistance was also found in L. innocua isolates. Resistant to Te Mi S Cip Nor was 7.7%, Te Mi S (7.7%), Te Mi (7.7%), and was 7.7% to Te S. Antibiotic resistance patterns for S. aureus isolats were demonstrated to Te Gm P Cip Cc E (6.0%), Te Gm Cip Cc E (3.6%), Te Gm P Cc (1.2%), Te Gm P (15.6%), Te Gm Cip (2.4%), Te P Cip (2.4%), Te Gm Cc (1.2%), Te Gm (56.6%), Te P (9.6%), and to Te Cip (1.2%). The results of this study suggest a high incidence of Lsteria spp. and S. aureus on poultry carcasses. The contaminated poultry carcasses may be a potential vehicle for foodborne infections due to multiple antimicrobial resistant organisms.

• Korean journal of applied entomology
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• v.48 no.3
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• pp.319-325
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• 2009

Woolly apple aphid, Eriosoma lanigerum, overwintered as adult or nymph stage on rootstocks, and crown- and root sucker in the soil. In an un sprayed apple orchard, the number of E. lanigerum colony started to increase from mid-April, showed the 1st peak between late June and early July, thereafter decreased followed by the 2nd peak in late July, and then again peaked in late September as the size in the 1st peak. In this orchard, the number of E. lanigerum colonies per tree did not exceed 3.5 colonies during the peak occurrence period, and was maintained around 2 colonies throughout seasons. In all seasons, parasitism of Aphelinus mali on E. lanigerum was much lower on root colonies than on aerial colonies that located on shoots and tree trunks above the ground. The parasitism of E. lanigerum was high in most orchards examined, showing parasitism of > 70% in maximum in most cases. In the laboratory bioassay for the mortality effects of several insecticides on E. lanigerum, fenitrothion, dichlorphos, machine oil, methidathion, thiacloprid, and imidacloprid showed 97.8, 96.8, 95.4, 91.5, 26.7, and 7.8% morality, respectively. Also, the adult emergence rates from A. mali mummies were 51.2, 72.6, 14.2, 3.5, 72.2, and 85.4% in the treatment of the above insecticides, respectively. Insecticides belong to neonicotinoid, which are newly developed to control aphids, showed low mortality against E. lanigerum. Fenitrothion and dichlorphos were effective on E. lanigerum control and had a low toxic to A. mali. Consequently, the insecticides should be useful in integrated pest management system for E. lanigerum in apple orchards.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.5 no.2
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• pp.160-171
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• 1995

The size characteristics of lead particle which is one of the important factors associated with absorption of lead were ignored in establishing lead standard. This study was conducted to investigate distribution of lead particles by operation of industry. Aerodynamic Mass Median Diameters (MMD) of airborne lead particles in the battery and litharge manufacturing industry were $14.1{\mu}m$ and $15.1{\mu}m$, respectively. There was no significant difference between those two values(p>0.05). However, the diameters in radiator manufacturing and secondary smelting industry were $1.3{\mu}m$, $4.9{\mu}m$, respectively. Those were significantly smaller than the particle sizes in other industries(p<0.05). Total lead concentrations in the secondary smelting industry were higher than those in the battery and litharge manufacturing industry. Total lead concentrations in other industries except radiator manufacturing industry exceeded the standard of $50{\mu}g/m^3$. Only radiator manufacturing industry indicated lead concentrations significantly lower than those in other industries(p<0.05). Concentrations of lead particles smaller than $1{\mu}m$ defined as respirable fraction by OSHA's CPA model assumption were $72.4{\mu}g/m^3$ in the secondary smelting industry, exceeding $50{\mu}g/m^3$. The relationship of concentrations between total lead and lead of particles smaller than $1{\mu}m$ was log Y = 0.46 logX + 0.06(n=119, $r^2=0.44$, p=0.0001). Relationship of respirable lead concentrations between OSHA and ACGIH was significantly detected in the litharge and battery manufacturing industry(p=0.0001), but was not significant in the radiator(p=0.2720) and secondary smelting manufacturing industry(p=0.2394). As MMDs of lead particles generated in industry were small, difference of respirable lead concentration between OSHA and ACGIH became smaller. There was a significant difference between concentrations respirable lead defined by two organizations such as OSHA and ACGIH in the battery and litharge manufacturing industry. Average concentration of respirable lead by ACGIH definition was 43.3 % of total lead in secondary smelting and 48.9 % in radiator manufacturing industry, and lower fractions were indicated in battery and litharge manufacturing industry. Relationships of total lead with IPM, TPM, and RPM were significant respectively(p=0.0001) and lead concentrations by particle size could be estimated using this relationship. Linear regression equation between total lead concentration(X) and ACGIH-RPM concentration(Y) was log Y = 0.76 log X - 0.40($r^2=0.89$, p=0.0001).

• The Korean Journal of Pesticide Science
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• v.5 no.4
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• pp.11-19
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• 2001

This review discusses the effects and roles of insect hormones and insect growth regulators (IGRs) on vitellogenesis in adult insects. Insect vitellogenesis is regulated by hormones such as juvenile hormone (JH), ecdysteroids, and neurosecretory hormones (ovaryecdysteroidogenic hormone : OEH) released by neurosecretory cells, diet, and other elements(male specific protein of sperm fluid). In the fat bodies, the vitellogenins are synthesized by the stimulation of JH released by corpus allatum (CA) and ecdysteroids produced by follicle cells with the ovary in most insects. Furthermore, vitellogenins are released into the hemolymph, transported to the ovarioles by carrier protein, and incorporated into oocytes for the developing ovary. Of IGRs, juvenile hormone and its mimics such as methoprene and pyriproxifen appear to have pharmacological effects such as membrane lysis, destruction of salivary grand and midgut epithlial cells, fat body cells, and ovarian tissue, and also anti-juvenile hormone such as precocenes I and II appear to have specific cytotoxicity such as inhibition of corpus allatum and oocytes development. These results suggest that IGRs may be useful as agents for integrated pest management.

• Journal of Pharmaceutical Investigation
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• v.35 no.6
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• pp.417-422
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• 2005

This study was aimed to design and formulate the moisture-activated patches containing ofloxacin and lidocaine for antibacterial and local anesthetic action. The solubility of lidocaine at $32^{\circ}C$ in various vehicles decreased in the rank order of PG $759.5{\pm}44.5\;mg/mL$ > PGL > IPM > PEG 300 > PEG 400 > Ethanol > PGMC > DGME > PGML > OA > $Captex^{\circledR}\;300$ > $Captex^{\circledR}\;200$ > water $(4.0{\pm}0.1\;mg/mL)$. Ofloxacin revealed very low solubility, which the highest solubility was obtained from PEG 400 $(18.7{\pm}6.3\;mg/mL)$ among the vehicles used. The addition of lactic acid increased the solubility of ofloxacin dramatically; the solubility at 5% lactic acid was $133.7{\pm}9.7\;mg/mL$. As $2-hydroxypropyl-{\beta}-cyclodextrin$ was added at the concentrations of 40, 80, 120, 160 and 200 mM, the solubilities of lidocaine and ofloxacin were enhanced up to three and two times, respectively, with concentration-dependent pattern. Gel intermediates for filmtype patches were prepared with mucoadhesive polymer, viscosity builders, lidocaine or ofloxacin at pH values from 5 to 7. Gels were cast onto a release liner and dried at room temperature. Dried patch was attached onto an adhesive backing layer, thus forming a patch system. Patches containing a single drug component were characterized by in vitro measurement of drug release rates through a cellulose barrier membrane. The release study was carried out at $37^{\circ}C$ using a Franz-type cell. Receptor solutions were isotonic phosphate buffers (pH 7.4). Samples $(100\;{\mu}L)$ were taken over 24 hours and quantitated by a verified HPLC method. The releases from all tested were proportional to the square root of time. The release rates were 0.9, 157.3 and $281.7\;{\mu}g/cm^{2}/min^{1/2}$ for the lidocaine patches and 19.8,37.2 and $50.7\;{\mu}g/cm^{2}/min^{1/2}$ for the ofloxacin patches at the concentrations of 0.3, 0.5 and 1 %, respectively. The release rates were dose dependent in both drug patches $(R^{2}\;=\;0.9077\;for\;lidocaine;\;R^{2}\;=\;0.9949\;for\;ofloxacin)$ and those were also thickness-dependent $(R^{2}\;=\;0.9246\;for\;lidocaine;\;R^{2}\;=\;0.9512\;for\;ofloxacin)$.

• The Korean Journal of Pesticide Science
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• v.4 no.4
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• pp.87-92
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• 2000

Recently, a new developed petroleiun spray oil(PSO; D-C Tron $Plus^{(R)}$) has been used to control key pests in integrated pest management (IPM) system of citrus orchards in Australia. The efficacy and phytotoxicity of the PSO against the citrus red mite (Panonychus citri) were compared with conventional pesticides (e.g.Tebufenpyrad, Bifenazate and Sun spray oil) in field condition in Jeju. And under PSO mixing spray with some fungicides, the occurrence of phytotoxic symptoms on citrus leaf was investigated. All concentrations of PSO spraying (0.25%, 0.33%, 0.5% and 1.0%) were significantly suppressed the citrus red mite to similar levels of other conventional pesticides. And the spraying of PSO levels ${\geq}0.5%$ was induced not only occurrence of some oil-sucked symptoms on leaf, but also increase of the dropping leaf and fruit rates. As results from mixing PSO spraying test with other fungicides, little burning on new flush shoot was founded only in PSO 1% plus Fluazinam treatment. From the results of this study, with the consideration of pesticidal efficacy and phytotoxicity, 0.25% and 0.33% PSO spraying level will be recommended for the control of citrus red mite during summer season in Jeju.