• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• v.1
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• pp.429-434
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• 2006

It is naturally to be expected that occupational stress on seafarers has specific characters compared to workers engaged in other industries. Because the physical rigors of working and living at sea has been endured as a part of job. The purpose of this paper is to figure out physical changes on seafarers resulted from ordinary shipboard life on the ocean-going cargo vessel. To do this, we performed biochemical inspections testing blood and urine for 28 crews, and measured heart rate of officers engaging in some bridge duties. The tests showed that creatinine, uric acid, total cholesterol, HDL-C, LDL-C of some crews fell down to level which could make a bad impact on human body. And the heart rate of deck officers had vibrated with rather wide amplitude whenever they have got some work-related psychological pressure.

• Journal of Pharmaceutical Investigation
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• v.41 no.4
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• pp.233-238
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• 2011

DEET, N,N'-diethyl-m-toluamide, is the most commonly used mosquito repellent. However, it can easily permeate through skin leading to toxic effects. A recent study showed that the ortho analogue of DEET showed enhanced repellency with reduced permeation compared to the commercially used meta analogue. Thus, in order to understand the differences in properties and effectiveness among the m-, o- and p-analogues of DEET, an HPLC-UV method was developed for separately analyzing the three analogues. Moreover, stability profiles at temperatures ranging from $30^{\circ}C$ to $70^{\circ}C$ as well as pH ranging from pH 3 to pH 9 have been determined. All three analogues were stable with no degradation observed during the 5 day period. o-DEET therefore could be further developed into a safer and more effective mosquito repellent.

• Microbiology and Biotechnology Letters
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• v.47 no.4
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• pp.473-486
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• 2019

In the aquatic environment, microorganisms are predominantly organized as biofilms. Biofilms are formed by the aggregation of microbial cells and are surrounded by a matrix of extracellular polymeric substances (EPS) secreted by the microbial cells. Biofilms are attached to various surfaces, such as the living tissues, indwelling medical devices, and piping of the industrial potable water system. Biofilms formed from a single species has been extensively studied. However, there is an increased research focus on multispecies biofilms in recent years. It is important to assess the microbial mechanisms underlying the regulation of multispecies biofilm formation to determine the drinking water microbial composition. These mechanisms contribute to the predominance of the best-adapted species in an aquatic environment. This review focuses on the interactions in the multispecies biofilms, such as coaggregation, co-metabolism, cross-species protection, jamming of quorum sensing, lateral gene transfer, synergism, and antagonism. Further, this review explores the dynamics and the factors favoring biofilm formation and pathogen transmission within the drinking water distribution systems. The understanding of the physiology and biodiversity of microbial species in the biofilm may aid in the development of novel biofilm control and drinking water disinfection processes.

• Journal of Korean Society for Atmospheric Environment
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• v.11 no.3
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• pp.263-272
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• 1995

Characteristics of anbient at Korean, Cheju Island have been studied during the intensive field study period on March 11 .sim. 17, 1994 in collaboration with other research organizations from Korea and abroad. The particle size distribution was measured using an Electrical Aerosol Analyzer(EAA) and an Optical particle Counter(OPC). Fine particles(PM1 and PM3) have been collected by filter pack samplers and their ionic compositions have been analyzed. sampling errors inherent to the filter pack sampling method are discussed and the method to analyze those errors are presented. The rine mass concentrations of this study show very similar mass concentrations when Seoul is clear. This is somewhat surprising result, because the most of researchers believe that Kosan is one of the cleanest area in Korea. Bimodal volume size distributions with peak values around 0.1 .sim. 0.2.mu.m and 3.mu.m in particle dimeter were observed for most of the measurement period, particle mass loadings and ionic composition data show a large fraction of particles are from non-sea salt origins. Estimation of water content and acidity of particles based on measurement by a gas/particle equilibrium model, SCAPE, reveals that the pH values of particles are comparable to or lower than those estimated based on measurements in Los Angeles, U.S.A. during the SCAQS study. These findings with the meteorological conditions during the study period suggest that the particles collected during the period have originated from outside Cheju Island.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.1
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• pp.9-15
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• 1999

Taurine contents in alcoholic and non alcoholic beverages, milk and milk products, sugars and condiments were determined for 83 food items commonly used by Koreans. Taurine concentrations of food samples were analyzed by using an automated amino acid analyzer(Biochrom 20, Pharmacia LKB) based on ion exchange chromatography. Taurine was not detected in most carbonated beverages, but found in a variety of fruit and vegetable beverages(canned) in the range of 0.13 ~1.43mg taurine/ 100g wt, and in instant coffee or tea beverages(canned) in the range of 0.10~0.41mg taurine/100g wt. The traditional Korean turbid rice wine(takju) sample contained the highest level of taurine (2.29mg/100g wt) among alcoholic beverages tested, which was followed by wine(0.59~0.88mg tau rine/100g wt) and beer(0.53~0.73mg taurine/100g wt). Ordinary milk samples contained 1.05~1.40 mg taurine/100g wt, and a variety of taurine supplemented infant formulas manufactured by Korean companies included 17.3~25.4mg taurine/100g wt. Taurine was not detected in most sugars and sweetners except a couple of chocolate samples(2.13~2.18mg taurine/100g wt). Exceptionally high level of taurine was found in a curry powder sample(16.9mg taurine/100g wt), while the rest of commonly used condiments contained less than 2.90mg taurine/100g wt.

• Korean Journal of Optics and Photonics
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• v.7 no.3
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• pp.238-243
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• 1996

We have developed XeCl laser pumped double-resonator Dye laser and two-stage amplifier system, and generated simultaneously of alternatively two wavelengths suitable in DIAL system. The developed double-resonator is composed of 1st and 2nd diffraction orders on light incidence angle in grazing-incidence grating method with 1200 g/mm. We have obtained spectral linewidth below 10 pm and the total efficiency dependent on pump energy over 6%. The tuning ranges dependent on 1st and 2nd diffraction orders are 434~470 nm and 436~468 nm, respectively. The amplification gain and rine-450 dye laser by using the double-resonator laser system and measured the distribution of $NO_2$ concentration over Suwon as the result of transmission of laser output of 6 mJ in this DIAL system. Consequently, we have confirmed that the developed dye laser system is very useful as the tunable source for DIAL.

• 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.

• Asian Journal of Turfgrass Science
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• v.8 no.3
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• pp.137-147
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• 1994

We have established a high-frequency plant regeneration system via organogenesis from mature seed of Korean lawngrass(Zoysia japonica Steud.). The effects of 2,4-dichiorophenoxy acetic acid (2,4-D), 6-furfuryl amino purine (kinetin), $\alpha$-naphthaiene acetic acid (NAA), N6-benzyl amino pu-rine (BAP), and casein hydrolysate (CR) on cailus induction and multiple shoot formation on ex-posure to light were evaluated. Callus produced on the Murashige and Skoog (MS) medium containing 2,4-D and kinetin had high organogenesis potency. A single addition of 1.0 mg $L-^1$ 2,4-D significantly induced callus. Also, 1.0 mg L-$^1$ 2,4-D, with the addition of 0.1 mg $L-^1$ kinetin highly enlianced callus induction. The trend of cailus induction was also found on mediurn containing 0.1 mg $L-^1$ BAP with 1.0 mg $L-^1$2,4-D, and 1 g $L-^1$ CR with the addition of 1.0 mg $L-^1$ 2,4-D. However, NAA was no effective on callus formation. The growth of root was significantly high in the presence of 0.1 mg $L-^1$ kinetin compared to other concentrations. Over 2 mg $L-^1$ kinetin highly lengthened roots. Fresh weight of plantlet was highest on medium containing 0.1 mg $L-^1$ 2,4-D. Also, on medium containing 0.1 mg $L-^1$ BAP, fresh weight of piantlet was highly enhanced. BAP was significantly effective on multiple shoot formation, particularly when 2.0 mg $L-^1$ was added with 0.1 mg $L-^1$ 2,4-D. Callus induction and multiple shoot formation were achieved on MS basal medium containing 1.0 g $L-^1$ CH.

• Annals of Clinical Neurophysiology
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• v.7 no.2
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• pp.65-74
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• 2005

Charcot-Marie-Tooth (CMT) disease was described by Charcot and Marie in France and, independently, by Tooth in England in 1886. CMT is the most common form of inherited motor and sensory neuropathy, and is a genetically heterogeneous disorder of the peripheral nervous system. Therefore, many genes have been identified as CMT-causative genes. Traditionally, subclassification of CMT have been divided into autosomal dominant inherited demyelinating (CMT1) and axonal (CMT2) neuropathies, X-linked neuropathy (CMTX), and autosomal recessive inherited neuropathy (CMT4). Recently, intermediate type (CMT-Int) with NCVs between CMT1 and CMT2 is considered as a CMT type. There are several related peripheral neuropathies, such as $D{\acute{e}}j{\acute{e}}rine$-Sottas neuropathy (DSN), congenital hypomyelination (CH), hereditary neuropathy with liability to pressure palsies (HNPP) and giant axonal neuropathy (GAN). Great advances have been made in understanding the molecular basis of CMT, and 17 distinct genetic causes of CMT have been identified. The number of newly discovered mutations and identified genetic loci is rapidly increasing, and this expanding list has proved challenging for physicians trying to keep up with the field. Identifying the genetic cause of inherited neuropathies is often important to determine at risk family members as well as diagnose the patient. In addition, the encouraging studies have been published on rational potential therapies for the CMT1A. Now, we develop a model of how the various genes may interact in the pathogenesis of CMT disorder.

• Journal of Physiology & Pathology in Korean Medicine
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• v.20 no.6
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• pp.1485-1496
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• 2006

Various kinds of related parameters on hypertension such as anti-oxygen effect, ACE, weight of body, hwart and kidney, blood pressure, heartbeat rates, contents of aldosterone, catecholamine, change rates, of plasma constituents, uric acid, BUN, creatinine were determined to verify the effects on hypertension by Kamisamul-tang (KSMT). And the results are concluded as follows. KSMT did not show any cytotoxicity at the range of concentration (1-250 ${\mu}g/m{\ell}$) on the human fibroblast cell (hFCs). KSMT decreased the production of reactive oxygen species (ROS) and DPPH generation depending on the concentration. KSMT significantly inhibited angiotensin converting enzyme(ACE) activity depending on the concentration compared with control. KSMT maintained body weight of body, heat and kidney nearly normal group in hypertensive rat induced by DOCA-salt. KSMT significantly blood pressure and heart beat rate compared with control in hypertensive rat induced by DOCA-salt. KSMT significantly decreased aldosterone, dopamine, norepineph- rine, epinephrine compared with control in hypertensive rat induced by DOCA-salt. KSMT significantly decreased the level of potassium and cloride compared with control wheareas increased that of calcium significantly in hypertensive rat induced by DOCA-salt. KSMT significantly decreased the level of uric acid and BUN compared with control in hypertensive rat induced by DOCA-salt. It is verified experimentally tat Kamisamultang(KMST) which has been used broadly as a clinical therapeutics in oriental medicine is effective for anti-hypertension mechanism. And it could be applied to develope the reliable prescriptions for anti-hypertension in the future.