• Journal of Food Hygiene and Safety
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• v.13 no.3
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• pp.189-195
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• 1998

Comparative insecticidal efficiency between compounded pyrethroids and its preparations cooperated with several synergists was studied. As main components, Group A contained Permethrine.Phthalthrine, Group B contained Permethrine.Furameth rine and Group C contained Phthalthrine.Dichlorvos. As synergists Piperonyl Butoxide (P.B.O.), N-Octylbicycloheptene dicarboximide (MGK-264), Octachlorodipropylether (8-421) was cooperated in each group. These preparations was treated to either Blattella G. or Musca D. for comparing about insecticidal efficiency[Knock-down rate ($KT_{50},\;KT_{90}$) and cumulative mortaility(percent/hrs)]. When the synergists was added to each Group, the insecticidal efficiency was improved. The most potent synergists was P.B.O. and the potency was decreased in the rank order of S-421>MGK-264. The more the concentration of synergists was increased, the more the insecticidal efficiency was improved. The rank order was $1:5{\geq}1:4>1.3$ in all three groups. The mortality (percent) according to time was similar to either $KT_{50}\;or\;KT_{90}$. Knock-down rate was appropriate parameter for the indicator about potency.

• Journal of Preventive Medicine and Public Health
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• v.3 no.1
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• pp.47-49
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• 1970

Laboratory susceptibility tests with various insecticides against houseflies(Musca domestica L.) were simultaneously conducted with larvae. As a result of these experment the following conclusion has been obtained. 1. The relative ratio to various insecticidal effects were naled>DDVP>diazinon>${\gamma}-BHC$>malathion>dieldrin>DDT in houseflies larvae. 2. It was noted that resistance to various insecticides in larvae was in proportion to resistance in adults.

• The Bulletin of The Korean Astronomical Society
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• v.35 no.2
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• pp.67.2-67.2
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• 2010

We present results of searching for the Very Low Luminosity Objects (VeLLOs; internal luminosity : $L_{int}$ < $0.1(d/140pc)^2\;L\odot$) in the Gould's Belt clouds using observations from 3.6 to 70 micron by the Spitzer Space Telescope. The clouds are California, Chamaeleon I, III, Musca, Lupus V, VI, Scorpius, Serpens, Corona Australis, Cepheus, and IC 5146 having the properties of active low-mass star-forming such as the Taurus cloud. The observing sensitivity of the Spitzer data is estimated to be about $L_{int}\;\geq\;5\times10^{-3}(d/140pc)^2\;L\odot$, a factor of 20 better than that of the Infrared Astronomical Satellite (IRAS). The observing data were processed by the c2d Legacy pipeline. As the criteria to select the VeLLOs, we slightly modified previous ones by Dunham et al. The most important criterion is a flux density at 70 micron that is directly converted to the internal luminosity. Also, we used additional criteria to remove the contamination of evolved stars and extragalaxies which have colors or SEDs very similar to YSOs. We identified a total of 64 new embedded VeLLO candidates with $L_{int}$ < $0.1(d/140pc)^2\;L\odot$, consisting of 8 in California, 15 in Chamaeleon-Musca, 13 in Scorpius-Lupus, 20 in Serpens, 3 in Corona Australis, 3 in Cepheus, and 2 in IC 5146. The classification of the spectral index (${\alpha}$) fitted to the shape of the Ks-24 micron SEDs shows most of VeLLO candidates (89%) are in types of Class I and Flat spectrum. We plot various diagrams based on their 2MASS-Spitzer bands colors and magnitudes to discuss properties of the VeLLOs. This search will lead us new adventure toward a future systematic study of the VeLLOs.

• Korean journal of applied entomology
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• v.33 no.3
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• pp.166-172
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• 1994

This study was conducted to investigate the resistance development and cross-res~stance of house fly (Musco dornestica L.) selected with chlorpyrifos, dichlorvos and permethrin for 11 generations to various p u p s of insectiodes. The resistance ratio (RR) of the chlorpyrifos-selected (Q), the d~chlorvos- selected (&) a d the permethrin-selected (R,) stmlns were 42 0. 38 and 187 tlrnes in female. and 42.0, 4 1 and 16.4 time; in male from the susceptible strain, respectively. The Rc strain showed highest cross-resistance to permethlin among the insectic~des tested: RR=7.5 and 9.6 tunes in female and male, respectively, whereas negatively correlated cross-resistance to propoxur was observed. High cross-res~atance to chlorpyrifos were produced for female (RR= 13.3) and male (RR=15.9) of Rd strain, and female (RR=8.7) and male (RR= 9 7) of R, strain. respectively

• Journal of Microbiology and Biotechnology
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• v.16 no.11
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• pp.1760-1772
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• 2006

Mature acetylcholinesterase (AChE) gene (gm, 1,836 bp) was cloned from the housefly and successfully expressed in the E. coli CodonPlus (DE3) RIL system (GM-E, 72 kDa) with a yield of 1,630 mU/g fresh cells. Using the gm, 10 kinds of mutants were constructed and expressed for enhancing sensitivity to insecticides. The sensitivity of these mutants to five kinds of organophosphate (OP) and three carbamate insecticides was investigated by measuring the apparent bimolecular inhibition constant ($k_i=k_2/K_d$). Surprisingly, the sensitivity of quadruple mutant IGFT was enhanced as much as 7-fold for acephate, 164-fold for demeton-S-methyl, 484-fold for dichlorvos, 523-fold for edifenphos, 30-fold for ethoprophos, 30-fold for benfuracarb, 404-fold for carbaryl, and 107-fold for furathiocarb, compared with that of GM-E, although the sensitivity of each single point mutant was slightly increased. These mutational studies indicated that (i) contradictory to Walsh et al. [39], the residue 327 is the important key residue for enhancing sensitivity as much as the residue 262, (ii) the residue 82 and additional residues of 234, 236, and 585 are also important, and (iii) sensitivity was cooperatively accelerated as the number of strategic mutations increased.

• Applied Biological Chemistry
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• v.37 no.2
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• pp.110-114
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• 1994

In searching for new insecticidal compounds from soil microorganisms, strains of streptomyces species showed insecticidal activities on Musca domestica and Bombyx mori were selected. Compounds I-IV, which were isolated from the metabolites of no. 46 strain, were identified as piericidin $C_1$, $C_2$, $C_3$ and $D_1$, respectively by UV and NMR data analyses.

• Journal of Life Science
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• v.29 no.5
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• pp.580-587
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• 2019

Benthic macroinvertebrates were analyzed in March, June, September, and December 2018 to evaluate water quality in the Songji River in Sacheon-ci, Korea. The identified benthic macroinvertebrates included 447 individuals belonging to 20 species, 18 families, 12 orders, 5 classes, and 3 phyla. Various ecological parameters were estimated for evaluation of the river status. The total ecological score of benthic macroinvertebrate community (TESB) varied from 17 (Station D) to 41 (Station A). The saprobic index and ecological score of benthic macroinvertebrate community (ESB) for the evaluation of river status revealed a water quality evaluation at Station A of II (oligosaprobic), indicating some satisfactory water protection. The benthic macroinvertebrate index (BMI) varied from 25.207 (Site C) to 39.348 (Station A). The evaluation of the river status at Stations C and D was polysaprobic, and sensitive taxa were absent. The mean Shannon-Weaver index (H') of diversity varied from 1.288 (Station D) to 2.250 (Station A). The classification of saprobity based on H' was ${\beta}$-mesosaprobic at Station A and ${\alpha}$-mesosaprobic at the other stations. The value of geometric density was varied from 1.229 (Station A) to 2.071 (Station D), with a mean of 1.582. An artificial load is being added to this river. One of load is the rectal river construction which flows straight through the river physics. Thus, the environment of living organisms deteriorates due to insufficient water. In order to secure the quality of the Songji River and a good environmental habitat, several low-height stepped-beam structures are required.

• Journal of Microbiology and Biotechnology
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• v.14 no.5
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• pp.1057-1062
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• 2004

The entomopathogenic bacterium Bacillus thuringiensis is the most widely used biopesticide. Insecticidal proteins, coded by genes located in plasmids, form typical parasporal, crystalline inclusions during sporulation. We isolated a Bacillus thuringiensis strain having insecticidal activity against larvae of the house fly (M. domestica) from the soils at a pig farm in Korea, and named it Bacillus thuringiensis SM. The culture filtrate from Bacillus thuringiensis SM showed strong lethality (83.3%) against M. domestica larvae. The parasporal crystal is enclosed within the spores' outermost envelope, as determined by transmission electron microscopy, and exhibited a bipyramidal form. The crystal proteins of strain SM consisted of five proteins with molecular weights of approximately ~130, ~80, ~68, ~42, and ~27 kDa on a 10% SDS-PAGE (major band, a size characteristic of Cry protein). Examination of antibiotic resistance revealed that the strain SM showed multiple resistant. The strain SM had at least three different plasmids with sizes of 6.6, 9.3, and 54 kb. Polymerase chain reactions (PCRs) revealed the presence of cry1, cry4A2, and cry11A1 genes in the strain SM. The cry1 gene profile of the strain SM appeared in the three respective products of 487 bp [cry1A(c)], 414 bp [cry1D], and 238 bp [cry1A(b)]. However, the strain SM has not shown the cry4A2 md cry11A1 genes. In in vivo toxicity assays, the strain SM showed high toxicity on fly larvae (M. domestic) [with $LC_{50}$ of 4.2 mg/ml, $LC_{90}$ of 8.2 mg/ml].