• The Korean Journal of Pesticide Science
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• v.20 no.4
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• pp.305-311
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• 2016

In cultivation environment, various pesticides are used and some of them could be volatilized into the air. This could affect farmer's health and also cause environmental pollution. This study was carried out to investigate the volatilization of pesticides, and use the reference data for preventing farmer's pesticide intoxication and securing worker safety. The experiment was conducted in a greenhouse using a lysimeter which was of $1m^2$ area and 1.5 m depth filled with upland soil. The pesticides treated in lysimeter soil were ethoprophos (5.0% GR), diazinon (34.0% EC), alachlor (43.7% EC), metolachlor (40.0% EC), chlorpyrifos (2.0% GR), pendimethalin (31.7% EC), carbaryl (50.0% WP), napropamide (50% WP), tebuconazole (25.0% WP) and imidacloprid (2.0% GR). Each pesticide was treated at a concentration of 770.5 mg based on A.I (%). The recovery of pesticide ranged from 77.4 to 99.3%. The volatilized pesticides in air were collected by personal air sampler with PUF tube at 4 l/min flow rate. In addition, temperature and humidity were measured. The collected samples were extracted using acetone in a soxhlet apparatus for 8 hours. The extracted pesticides were resoluted with acetonitrile and diluted 5 times. It was analyzed with LC-MS/MS. For 720 hours experiment, the largest vaporization amount of each pesticide in air was ethoprophos $15.24{\mu}g/m^3$, diazinon $5.14{\mu}g/m^3$, pendimethalin $2.70{\mu}g/m^3$, chlorpyrifos $1.76{\mu}g/m^3$, alachlor $1.40{\mu}g/m^3$, metolachlor $1.12{\mu}g/m^3$, carbaryl $0.27{\mu}g/m^3$, napropamide $0.22{\mu}g/m^3$, tebuconazole $0.11{\mu}g/m^3$ and imidacloprid $0.05{\mu}g/m^3$. The R value (coefficient of correlation) between volatilization and vapor pressure of pesticides is higher than 0.99. Therefore, there is high correlation between volatilization and vapor pressure of pesticides.

• Food Science and Preservation
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• v.22 no.4
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• pp.505-511
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• 2015

This study was performed to investigate the effect of drying temperature on the quality characteristics and antioxidant activity of blueberry. Blueberries were dried at different times and temperatures, including A ($40^{\circ}C$, 72 hr), B ($40^{\circ}C$, 48 h and $50^{\circ}C$, 24 hr), C ($50^{\circ}C$, 72 hr), and D ($60^{\circ}C$, 72 hr). The yield and pH ranges of blueberry were determined to be 17.73~31.17% and 3.20~3.25, respectively. The yield rate of A treatments, soluble solid of D treatments, was the highest. The yield rate and soluble content was the highest in the treatment of A and D, respectively. The moisture content and water activity were significantly decreased with the increase in drying temperature (p<0.05). The L value of A treatment, and a and b values of D treatment were the greatest. In the analysis of texture analyzer, hardness, springiness, cohesiveness, gummiess and chewiness were significantly increased with the increase in drying temperature (p<0.05). In the sensory evaluation of blueberry, the appearance and color were the highest in the A treatment. The moisture, texture and taste was highest in the B treatment. The overall acceptability was in the order of B > A > C >D. The total polyphenol content and DPPH radical-scavenging activity were 9.21~13.05 mg/GAEg and 61.90~81.42%, respectively, which were significantly decreased with the increase in drying temperature (p<0.05). Therefore, the optimum time and temperature for blueberry drying was founded to be B treatment ($40^{\circ}C$, 48 hr and $50^{\circ}C$, 24 hr) among other treatments.

• Korean Journal of Animal Reproduction
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• v.24 no.4
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• pp.357-364
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• 2000

Members of the glycoprotein family, which includes CG, LH, FSH and TSH, comprise two noncovalently linked $\alpha$- and $\beta$-subunits. Equine chorionic gonadotropin (eCG), known as PMSG, has a number of interesting and unique characteristics since it appears to be a single molecule that possesses both LH- and FSH-like activities in other species than the horse. This dual activity of eCG in heterologous species is of fundamental interest to the study of the structure-function relationships of gonadotropins and their receptors. CG and LH $\beta$ genes are different in primates. In horse, however, a single gene encodes both eCG and eLH $\beta$ -subunits. The subunit mRNA levels seem to be independently regulated and their imbalance may account for differences in the quantities of $\alpha$ - and $\beta$-subunits in the placenta and pituitary. The dual activities of eCG could be separated by removal of the N-linked oligosaccharide on the $\alpha$-subunit Asn 56 or CTP-associated O-linked oligosaccharides. The tethered-eCG was efficiently secreted and showed similar LH-like activity to the dimeric eCG. Interestingly, the FSH-like activity of the tethered-eCG was increased markedly in comparison with the native and wild type eCG. These results also suggest that this molecular can implay particular models of FSH-like activity not LH-like activity in the eCG/indicate that the constructs of tethered molecule will be useful in the study of mutants that affect subunit association and/or secretion. A single-chain analog can also be constructed to include additional hormone-specific bioactive generating potentially efficacious compounds that have only FSH-like activity. The LH/CG receptor (LH/CGR), a membrane glycoprotein that is present on testicular Leydig cells and ovarian theca, granulosa, luteal, and interstitial cells, plays a pivotal role in the regulation of gonadal development and function in males as well as in nonpregnant and pregnant females. The LH/CGR is a member of the family of G protein-coupled receptors and its structure is predicted to of a large extracellular domain connected to a bundle of seven membrane-spanning a-helices. The LH/CGR phosphorylation can be induced with a phorbol ester, but not with a calcium ionophore. The truncated form of LHR also was down-regulated normally in response to hCG stimulation. In contrast, the cell lines expressing LHR-t631 or LHR-628, the two phosphorylation-negative receptor mutant, showed a delay in the early phase of hCG-induced desensitization, a complete loss of PMA-induced desensitization, and an increase in the rate of hCG-induced receptor down-regulation. These results clearly show that residues 632~653 in the C-terminal tail of the LHR are involved in PMA-induced desensitization, hCG-induced desensitization, and hCG-induced down-regulation. Recently, constitutively activating mutations of the receptor have been identified that are associated with familial male-precocious puberty. Cells expressing LHR-D556Y bind hCG with normal affinity, exhibit a 25-fold increase in basal cAMP and respond to hCG with a normal increase in cAMP accumulation. This mutation enhances the internalization of the free and agoinst-occupied receptors ~2- and ~17- fold, respectively. We conclude that the state of activation of the LHR can modulate its basal and/or agonist-stimulated internalization. Since the internalization of hCG is involved in the termination of hCG actions, we suggest that the lack of responsiveness detected in cells expressing LHR-L435R is due to the fast rate of internalization of the bound hCG. This statement is supported by the finding that hCG responsiveness is restored when the cells are lysed and signal transduction is measured in a subcellular fraction (membranes) that cannot internalize the bound hormone.

• Korean Journal of Ecology and Environment
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• v.50 no.4
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• pp.459-469
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• 2017

Nitrogen (N) loading from domestic, agricultural and industrial sources can lead to excessive growth of macrophytes or phytoplankton in aquatic environment. Many studies have used stable isotope ratios to identify anthropogenic nitrogen in aquatic systems as a useful method for studying nitrogen cycle. In this study to evaluate the precision and accuracy of denitrification bacteria method (Pseudomonas chlororaphis ssp. Aureofaciens ($ATCC^{(R)}$ 13985)), three reference (IAEA-NO-3 (Potassium nitrate $KNO_3$), USGS34 (Potassium nitrate $KNO_3$), USGS35 (Sodium nitrate $KNO_3$)) were analyzed 5 times repeatedly. Measured the ${\delta}^{15}N-NO_3$ and ${\delta}^{18}O-NO_3$ values of IAEA-NO-3, USGS 34 and USGS35 were ${\delta}^{15}N:4.7{\pm}0.1$‰ ${\delta}^{18}O:25.6{\pm}0.5$‰, ${\delta}^{15}N:-1.8{\pm}0.1$‰ ${\delta}^{18}O:-27.8{\pm}0.4$‰, and ${\delta}^{15}N:2.7{\pm}0.2$‰ ${\delta}^{18}O:57.5{\pm}0.7$‰, respectively, which are within recommended values of analytical uncertainties. Also, we investigated isotope values of potential nitrogen source (soil, synthetic fertilizer and organic-animal manures) and temporal patterns of ${\delta}^{15}N-NO_3$ and ${\delta}^{18}O-NO_3$ values in river samples during from May to December. ${\delta}^{15}N-NO_3$ and ${\delta}^{18}O-NO_3$ values are enriched in December suggesting that organic-animal manures should be one of the main N sources in those areas. The current study clarifies the reliability of denitrification bacteria method and the usefulness of stable isotopic techniques to trace the anthropogenic nitrogen source in freshwater ecosystem.

• Korean Journal of Food Science and Technology
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• v.42 no.1
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• pp.27-32
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• 2010

This study was conducted to monitor aflatoxins in various medicinal herbs, providing available data for the safety of those products. To monitor aflatoxins in medicinal herbs, a total of 400 samples of 40 different herbs were collected in commercial retailers in Seoul, Daejeon, Gwangju, Daegu, and Busan from March to August, 2008. The samples that passed the sensory evaluation were tested for aflatoxins. Aflatoxins in samples were analyzed by HPLC-florescence coupled with photochemical enhancement. Samples were extracted with 70% methanol and then diluted to the appropriate concentration. A refining process was performed using an immunoaffinity column. The analytical method used in this study was validated. The $R^2$ value for aflatoxin $B_1$ was 0.99946, and the detection range was from 0.25 to 10.0 ng/mL. The accuracy of the analysis was ranged from 83.2% to 101.8%. The relative standard deviation (RSD) in the aflatoxin $B_1$ analysis was 3.4%, demonstrating the precision of this method. In addition, the detection limit and quantitative analysis limit of aflatoxin $B_1$ was $0.53\;{\mu}g/kg$ and $1.76\;{\mu}g/kg$, respectively. These results indicated that the analytical method used in this study was appropriate. The results of HPLC showed that 1% (4 samples) of the samples may contain aflatoxins. The concentration of quantified aflatoxin was $2.3\;{\mu}g/kg$ for both Quisqualis fructus and Remotiflori radix samples. The other samples were below the limit of quantification. Moreover, the concentration of aflatoxin $B_1$ which is made by specific fungi were below the level of regulation. Only 20% of aflatoxin $B_1$ were transferred to hot water. Therefore, the levels of aflatoxins in medicinal herbs were considered to be safe especially considering the aflatoxin transfer ratio.

• Restorative Dentistry and Endodontics
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• v.27 no.2
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• pp.183-195
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• 2002

흑색 색소를 형성하는 그람음성 혐기성 세균은 급성 임상 증상을 가진 환자의 근관에서 자주 발견되는 세균으로서 세균 및 세균의 성분과 산물이 치근단 병소의 생성과 밀접하게 연관된 것으로 알려져 있다. 본 연구는 흑색 색소를 형성하는 그람음성 혐기성 세균 중 가장 발현율이 높은 Prevotella nigrescens가 배양된 세포에 미치는 세포 독성을 연구하고자 하였다. 두 가지 세포주 및 사람의 치은섬유모세포를 일차배양하여 사용하였으며, 세포주에 따른 독성 발현에 차이가 있는지를 비교하였다. P. nigrescens ATCC 33563 표준 균주 및 임상 균주로는 환자의 감염된 근관으로부터 165 rRNA primer를 사용한 중합효소 연쇄반응으로 P. nigrescens 6 균주를 동정하여 사용하였다. 세균배양액, 세균의 초음파 추출단백질 및 lipopolysaccharide (LPS)를 MC3T3-El 조골세포, NIH3T3 섬유모세포 및 치은섬유모세포에 첨가한 후 MTT분석법으로 세포의 활성을 측정하였으며, 세포의 형태학적 변화를 도립현미경으로 관찰하였다. 세균배양액을 100$\mu\textrm{l}$ 첨가한 경우는 세가지 세포주 모두에서 통계적으로 유의하게 세포의 활성을 억제하였다. 세균의 초음파 추출단백질 12.5$\mu\textrm{g}$/ml 와 25$\mu\textrm{g}$/ml 는 NIH3T3세포에 통계적으로 유의한 세포독성을 보였다. 세 가지 세포주에 대한 LPS의 세포 독성 효과는 첨가된 LPS의 농도 및 균주에 따라 다양하게 나타났다. 심하게 손상된 세포는 세포의 단일층이 수축되고 세포가 응집되었으며 세포가 배양용기의 바닥에서 떨어지는 양상이 도립 현미경하에서 관찰되었다. 본 연구의 결과 P. nigrescens가 숙주 반응을 조절하여 치수 및 치근단 병소의 유발 및 악화에 기여하는 세균으로 작용할 수 있음을 시사한다. 조직과 함께 제거하고 포르말린에서 48시간 고정시킨 후 파라핀에 포매한 다음에 micro-tome을 사용하여 6$\mu\textrm{m}$로 serial section을 시행하였다. 정중선 부위의 시편에 Hematoxylin-Eosin staining을 시행한 후 Olsson, Orstavik 그리고 Mjor 등의 방법에 따라 조직학적 변화를 관찰한 후 slight(1), moderate(2), severe inflammation(3)의 단계로 분류하였다. 얻어진 결과를 통계처리 프로그램인 Jandel사의 Sigmastat을 이용하여 Kruskal Wallis Test로 통계처리를 하였다. 결과 : (Table omitted) 결론 : 1) Pulp Canal Sealer를 제외한 모든 군에서 시간이 지남에 따라 유의성 있게 염증이 감소되는 양상을 보였다(p<0.05). 2) Pulp Canal Sealer는 1주, 2주, 12주에서 강한 염증반응을 보였다. 3) AH 26과 AH Plus에서는 1주, 2주에서 강한 염증반응을 보였으나 12주에서는 염증반응이 감소하였다. 4) 새로 개발된 봉함제 Adseal-1,2는 1주, 2주에서는 가장 약한 염증반응을 보이나 4주, 12주 후에는 AH Plus와 비슷한 수준의 염증 반응을 보였다. 5) Pulp Canal Sealer를 제외한 모든 군에서 인정할 만한 생체친화성을 보였다. 6) Adseal-2가 Adseal-1에 비하여 전반적으로 낮은 염증반응을 보였다. 7) 각 군간 결과의 차이에 통계적 유의성은 없었다(p>0.05).mmunity. Then, a hierarchical language is to defeat its own purpose.중 행정부가 북한에 대해 실시한 포용정책이 어떠한 성과를 거두고 어떠한 문제점을 간과하고 있는가에 대해 논의하고, 대북 정책의 새로운 지평을 논의하는 것을 목적으로 하고 있다. 1) 포용 정책은 세계의

• Journal of Embryo Transfer
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• v.18 no.1
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• pp.61-68
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• 2003

Considerable attention has been focused on the cryopreservation of semen and estrus induction in dog, as consequence of poor productivity caused by long anestrus period, in order to enhance the productivity of youngs and to preserve the breeds. The objectives of this study were to improve reproductive efficiency of artificial insemination with fresh- and frozen-semen following estrus induction in dog. Fifty infertilie dogs (age 2~3 years) were selected fur the study and divided into three different estrus induction treatment groups. Group 1 : dogs (n=15) were given clomifene (0.1 mg/kg) orally f3r five days at 12 hr intervals. Croup 2: dogs (n=15) were given bromocriptine (50 $\mu$g/kg) orally for five days at 12 hr intervals, followed by single injection intravenously of 500 IU GnRH (Croup 3, n=20) when pro-estrus occurred. After being treated, the dogs were evaluated fur the rates of estrus induction and time interval lapses from treatment to beginning of the pro-estrus. The rates of pregnancy in estrus inducted dogs mated naturally compared to those inseminated artificially with ejaculated fresh semen and frozen-thawed semen. Estrus detection was performed using the method of vaginal smear and confirmed by the plasma progesterone assay. Pregnancy was confirmed by ultrasonograpy on day 25, 35 and 55 post insemination. The ejaculated semen was exposed to a mixture of Tris extender with cryoprotectant (Trisma, 81 mM; TES, 209 mM; citric acid, 6 mM; glucose, 5 mM; glycerol, 8%) and cryopreserved gradually by slow-cooling at 17 co above the surface of liquid nitrogen (L$N_2$) for 23 min. The use of fresh semen, the pregnancy rates were observed 66.6, 66.6, 75.0 and 83.3% in natural estrus, clomifene induced, bromocriptine induced and a combination of GnRH and bromocriptine, respectively. The use of frozen-thawed semen, the pregnancy rates were observed 66.6, 33.3, 50.0 and 60.0% in natural estrus, clomifene induced, bromocriptine induced and a combination of GnRH and bromocriptine, respectively. No difference was observed in the number of offspring produced among natural estrus and treated groups inseminated with fresh or frozen-thawed semen. In conclusion, there was no significant differences in the pregnancy rate of dogs between group treated with a combination of GnRH and bromocriptine and group treated clomifene or bromocriptine only. However, frozen-thawed semen can be used successfully fur artificial insemination in dog.

• Parasites, Hosts and Diseases
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• v.25 no.2
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• pp.159-167
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• 1987

To analyse the antigen specificity of patients sera from 24 confirmed neurocysticercosis and a monoclonal antibody, SDS-PAGE using 10~15% linear gradient gel and EITB were done. Cystic fluid, saline extracts of scolex and of whole worm of C. cellulosae, saline extracts of sparganum, hydatid cyst fluid, saline extracts of Fasciola, Clonorchis and Paragonimus were used as antigen. Of protein bands in cystic fluid of C. cellulosae, patient sera reacted frequently to bands of 152, 94, 64, 48, 24, 15, 10 and 7kDa proteins. To saline extracts of scolex and whole worm of C. cellulosae, patients sera reacted frequently to 94, 64, 52, 39, 34, 15 and 10kDa bands. Two bands in sparganum extract (130 and 64kDa) and two bands in hydatid cyst fluid (52 and 27kDa) were cross-reacting bands with sera from cysticercosis patients. Saline extracts of Fasciola, ClonorchiJ and Paragonimus did 'not exhibit cross-reacting bands. Monoclonal antibody to cystic fluid of C. cellulosae was found to react with low molecular weight proteins of 15, 10 and 7kDa.

• Journal of Food Hygiene and Safety
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• v.29 no.2
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• pp.131-140
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• 2014

The objective of this study was to develop a simultaneous method of 8 penicillin antibiotics including amoxicillin, ampicillin, cloxacillin, dicloxacillin, nafcillin, oxacillin, penicillin G and penicillin V in meat using LC-MS/MS. The procedure involves solid phase extraction with HLB cartridge and subsequent analysis by LC-MS/MS. To optimize MS analytical condition of 8 compounds, each parameter was established by multiple reaction monitoring in positive ion mode. The chromatographic separation was achieved on a $C_{18}$ column with a mobile phase of 0.05% formic acid and 0.05% formic acid in acetonitrile at a flow rate of 0.2 mL/min for 20 min with a gradient elution. The developed method was validated for specificity, linearity, accuracy and precision in beef, pork and chicken. The recoveries were 71.0~106%, and relative standard deviations (RSD) were 4.0~11.2%. The limit of detection (LOD) and the limit of quantification (LOQ) were 0.003~0.008 mg/kg and 0.01~0.03 mg/kg, respectively, that are below maximum residue limit (MRL) of the penicillins. This study also performed survey of residual penicillin antibiotics for 193 samples of beef, pork and chicken collected from 9 cities in Korea. Penicillins were not found in all the samples except a sample of pork which contained cloxacillin (concentration of 0.08 mg/kg) below the MRL (0.3 mg/kg).

• Journal of Mushroom
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• v.22 no.2
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• pp.60-66
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• 2024

This study was conducted to selection and investigate appropriate conditions for mass production of antagonistic microbes to control cobweb disease caused by Cladobotryum mycophilum. A grampositive bacterium was isolated from spent substrate of Agaricus bisporus and showed significant antagonistic activity against Cladobotryum mycophilum. The bacterium was identified as Bacillus altitudinis. based on the cultural, biochemical and physiological characteristics, and 16S rRNA sequence. The isolate is saprophytic, but not parasitic nor pathogenic to cultivated mushroom whereas it showed strong inhibitory effects against C. mycophilum cells in vitro. The control efficacy of B. altitudinis HC7 against cobweb disease of C. mycophilum was up to 78.2% on Agaricus bisporus. The suppressive bacterium may be useful for the development of biocontrol system. To define the appropriate conditions for the mass production of the Bacillus altitudinis HC7, we have investigated appropriate culture conditions and effects of various nutrient source on the bacterial growth. The appropriate initial pH and temperature were determined as pH 6.0 and 30℃, respectively. The appropriate concentration of medium elements for the growth of pathogen inhibitor bacterium(Bacillus altitudinis HC7) was determined as follows: 3.0% soluble startch, 10% soytone, 1.0% (NH₄)₂HPO₄, 1.0 mmol KCl, and 0.5% L-asparagine.