• Korean Journal of Environment and Ecology
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• v.33 no.5
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• pp.605-619
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• 2019

The objective of this study was to analyze eutrophication characteristics, empirical model analysis, and variation of water quality according to monsoon intensity in Hapcheon Reservoir for 16 years from 2002 to 2017. Long-term annual water quality analysis showed that Hapcheon Reservoir was in a meso-nutrition to eutrophic condition, and the eutrophic state intensified after the summer monsoon. Annual rainfall volume (high vs. low rainfall) and the seasonal intensity in each year were the key factors that regulate the long-term water quality variation provided that there is no significant change of the point- and non-point source in the watershed. Dry years and wet years showed significant differences in the concentrations of TP, TN, BOD, and conductivity, indicating that precipitation had the most direct influence on nutrients and organic matter dynamics. Nutrient indicators (TP, TN), organic pollution indicators (BOD, COD), total suspended solids, and chlorophyll-a (Chl-a), which was an estimator of primary productivity, had significant positive relations (p<0.05) with precipitation. The Chl-a concentration, which is an indicator of green algae, was highly correlated with TP, TN, and BOD, which differed from other lakes that showed the lower Chl-a concentration when nutrients increased excessively. Empirical model analysis of log-transformed TN, TP, and Chl-a indicated that the Chl-a concentration was linearly regulated by phosphorus concentration, but not by nitrogen concentration. Spatial regression analysis of the riverine, transition, and lacustrine zones of $log_{10}TN$, $log_{10}TP$, and $log_{10}CHL$ showed that TN and Chl-a had significant relations (p<0.005) while TN and Chl-a had p > 0.05, indicating that phosphorus had a key role in the algal growth. Moreover, the higher correlation of both $log_{10}TP$ and $log_{10}TN$ to $log_{10}CHL$ in the riverine zone than the lacustrine zone indicated that there was little impact of inorganic suspended solids on the light limitation in the riverine zone.

• Journal of Acupuncture Research
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• v.24 no.3
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• pp.175-185
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• 2007

Objectives : The purpose of this study is to evaluate the clinical effect of Moxa-Pellet treatment for nasal symptoms and quality of life(QOL) in patients with allergic rhinitis. Methods: Subjects were voluntarily recruited through newspaper and internet advertisement. In this randomized, single blind and controlled study, experimental group (n=19) received real Moxa-Pellet treatment and control group(n=20) received sham Moxa-Pellet treatment for 3 weeks. Acupuncture points used were $LI_4$, $ST_{36}$, $LU_7$, $GV_{14}$ and $GB_{20}$. Patient's nasal symptoms and QOL were assessed before and after 3 weeks treatment by the Nasal Symptom Scores(NSS) and the Medical Outcomes Study 36-Item Short-Form Health Survey(SF-36). Results : The results were as follows; 1. Among items of NSS, Sneezing' Rhinorrhea' Itching scores and Total Nasal Symptom Scores(TNSS) were significantly improved in experimental group after 3 weeks Moxa- Pellet treatment(p<0.05). In control group, there was no significant difference in all items except Headache item of NSS. 2. Among 8 domains of SF- 36, experimental group showed significant difference in Role-Emotional(RE), Mental Health(MH) and Bodily Pain(Bp) after 3 weeks Moxa- Pellet treatment(p<0.05). Control group showed no significant difference in all domains except one domain(Role limitation-physical). Conclusions: These results suggest that Moxa-Pellet treatment can be applicable to improve nasal symptoms and QOL in the patients with allergic rhinitis. Further long tenn studies on the Moxa-Pellets treatment's sustaining power and safety is needed.

• Journal of Microbiology and Biotechnology
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• v.30 no.1
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• pp.136-145
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• 2020

Chlorella sp. HS2, which previously showed excellent performance in phototrophic cultivation and has tolerance for wide ranges of salinity, pH, and temperature, was cultivated heterotrophically. However, this conventional medium has been newly optimized based on a composition analysis using elemental analysis and ICP-OES. In addition, in order to maintain a favorable dissolved oxygen level, stepwise elevation of revolutions per minute was adopted. These optimizations led to 40 and 13% increases in the biomass and lipid productivity, respectively (7.0 and 2.25 g l^-1d^-1 each). To increase the lipid content even further, 12 h heat shock at 50℃ was applied and this enhanced the biomass and lipid productivity up to 4 and 17% respectively (7.3 and 2.64 g l^-1d^-1, each) relative to the optimized conditions above, and the values were 17 and 14% higher than ordinary lipid-accumulating N-limitation (6.2 and 2.31 g l^-1d^-1). On this basis, heat shock was successfully adopted in novel Chlorella sp. HS2 cultivation as a lipid inducer for the first time. Considering its fast and cost-effective characteristics, heat shock will enhance the overall microalgal biofuel production process.

• Restorative Dentistry and Endodontics
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• v.37 no.2
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• pp.79-83
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• 2012

Objectives: The purpose of this study was to evaluate the relation between intentionally induced internal stress and cyclic fatigue failure of .06 taper ProFile. Materials and Methods: Length 25 mm, .06 taper ProFile (Dentsply Maillefer), and size 20, 25, 30, 35 and 40 were used in this study. To give the internal stress, the rotary NiTi files were put into the .02 taper, Endo-Training-Bloc (Dentsply Maillefer) until auto-stop by torque controlled motor. Rotary NiTi files were grouped by the number of induced internal stress and randomly distributed among one control group and three experimental groups (n = 10, Stress 0 [control], Stress 1, Stress 2 and Stress 3). For cyclic fatigue measurement, time for separation of the rotary NiTi files was recorded. The fractured surfaces were observed by field emission scanning electron microscope (FE-SEM, SU-70, Hitachi). The time for separation was statistically analyzed using two-way ANOVA and post-hoc Scheffe test at 95% level. Results: In .06 taper ProFile size 20, 25, 30, 35 and 40, there were statistically significant difference on time for separation between control group and the other groups (p < 0.05). Conclusion: In the limitation of this study, cyclic fatigue failure of .06 taper ProFile is influenced by internal stress accumulated in the files.

• Journal of Chest Surgery
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• v.30 no.9
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• pp.920-926
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• 1997

Remarkable effect of pain relief and prevention of the postoperative Complications after thoracotomy has been achieved by continuous intravenous analgesia. This study was carried out with thirty patients who underwent posterolateral thoraco tony. The patients were divided into three groups: Group I(n= 10), the patients with intermittent intramuscular analgesia(piroxicam 20 mg), Group II(n=10), the patients with continuous epidural analgesia(0.5% bupivacaine 30m1 + normal saline 30 ml + morphine 10 mg), and Group III(n= 10) the patients with controlled intravenous infusion of analgesics(fentanyl 2500 mfg +normal saline 10 ml). The results w re as follows; 1) There were no significant changes of vital signs, between groups. 2) Tidal volume and FVC were significantly improved in the group II and III compared with the group I during the first postoperative day. 3) A significant reduction of immediate post-thoracotomy pain was achieved in the group II and III compared with the group I. 4) The limitation of motion in the operative side was less in the group II and III compared with the group I. 5) A signi(icant reduction of the postoperative analgegics consumption was noticed in group II and III. 6) Significant complications were not occured during follow-up period in all groups.

• Ocean and Polar Research
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• v.35 no.2
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• pp.147-155
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• 2013

The purpose of this study is to investigate seasonal difference in linear trends in satellite-derived chlorophyll-a concentration (Chl-a) and their related environmental changes in the South Sea of Korea (SSK) and East China Sea (ECS) for recent 15 years (Jan. 1998~Dec. 2012) by analyzing climatological data of Chl-a, Rrs(555), sea surface wind (SSW) and nutrient. A linear trend analysis of Chl-a data reveals that, during recent 15 years, the spring bloom was enhanced in most of the ECS, while summer and fall blooms were weakened. The increased spring (Mar. - May) Chl-a was associated with strengthened winter (Dec. - Feb.) wind that probably provided more nutrient into the upper ocean from the deep. The causes of decreased summer (Jun. - Aug.) Chl-a in the northern ECS were uncertain, but seemed to be related with the nutrient limitation. Recently (after 2006), low-salinity Changjiang diluted water in the south of Jeju and the SSK had lower phosphate that caused increase in N/P ratio with Chl-a decrease. The decreased fall (Sep. - Nov.) Chl-a was associated with weakened wind that tends to entrain less nutrient into the upper ocean from the deep. This study suggests that phytoplankton in the ECS differently changes in response to environmental changes depending on season and region.

• Journal of Korean Medicine Rehabilitation
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• v.27 no.3
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• pp.47-60
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• 2017

Objectives The aim of this research is to assess the effects of bee venom acupuncture for knee osteoarthritis. Methods For a systematic review, we constructed a key question as the effect of bee venom acupuncture for knee osteoarthritis and selected RCTs and nRCTs. We searched the following 15 databases without a language restriction: Pubmed, EMBASE, Cochrane CENTRAL (CENTRAL), CINAHL, AMED, seven Korean medical databases (KoreaMed, Kmbase, KISS, NDSL, KISTI, Koreantk, OASIS) and three Chinese databases including CNKI, Wanfang and VIP database. Results A total of 300 potentially relevant studies were identified; only 13 studies were selected for systematic review. Almost studies showed that bee venom acupuncture has significant effect on knee osteoarthritis. 5 studies comparing bee venom acupuncture with acupuncture were included in the meta-analysis. The effect size of standardized mean difference (SMD) was analyzed as 'small effect' with 0.47 (95% CI: 0.10~0.83, Z=2.49, p=0.01). Conclusions The research showed that bee venom acupuncture can significantly reduce pain, stiffness and improve the quality of life of patients with knee osteoarthritis. However, most of the studies included in the analysis were evaluated as methodologically high risk of bias. This suggests that there is limitation applying this study. In the future, more Randomized Controlled trial should be actively conducted.

• Tuberculosis and Respiratory Diseases
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• v.47 no.2
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• pp.195-208
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• 1999

Background: Pulmonary infiltrate in immunocompromised hosts has many infectious and non-infectios etiologies. To evaluate the diagnostic yield and therapeutic implication of two invasive diagnostic methods, such as bronchoscopy and surgical lung biopsy, we performed retrospective analysis of these patients. Methods: All immunocompromised patients admitted to Samsung Medical Center from October 1995 to August 1998 who underwent bronchoscopy and/or surgical lung biopsy for the diagnosis of pulmonary infiltrates were included in this study. Confirmative diagnostic yield, the rate of changed therapeutic plan and patients' survival were investigated. Results: Seventy-five episodes of pulmonary infiltrates developed in 70 patients(M : F=46 : 24, median age 51). Underlying diseases of patients were hematologic malignancy(n=30), organ transplantation(n=11), solid tumor(n= 12), connective tissue disease(n=6) and others. Confirmative diagnosis was made in total 53 cases (70.7%), of which 70.2% had infectious etiology. Diagnostic yields of bronchoscopy, bronchoalveolar lavage(BAL), transbronchiallung biopsy(TBLB) and surgical lung biopsy were 35.0%(21/60), 31.4%(16/51), 25.0%(9/36) and 80.0%(20/25). Therapeutic plan was changed in 40%(24/60) of patients after bronchoscopy and in 36%(9/25) of patients after surgical lung biopsy. More patients survived (84.4% vs 60.5%, p=0.024) when therapeutic plan was changed after invasive diagnostic study. Conclusion: Bronchoscopy and surgical lung biopsy are helpful for the therapeutic implication of pulmonary infiltrates in immunocompromised hosts. Large-scale prospective case-control study may further clarify their limitation and usefulness.

• Geophysics and Geophysical Exploration
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• v.18 no.2
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• pp.64-73
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• 2015

Recently, hydraulic fracturing is used in various fields and microseismic monitoring is one of the best methods for judging where hydraulic fractures exist and how they are developing. When locating microseismic events using single vertical well data, distances from the vertical array and depths from the surface are generally decided using time differences between compressional (P) wave and shear (S) wave arrivals and azimuths are calculated using P wave hodogram analysis. However, in field data, it is sometimes hard to acquire P wave data which has smaller amplitude than S wave because microseismic data often have very low signal to noise (S/N) ratio. To overcome this problem, in this study, we developed a grid search algorithm which can find event location using all combinations of arrival times recorded at receivers. In addition, we introduced and analyzed the method which calculates azimuths using S wave. The tests of synthetic data show the inversion method using all combinations of arrival times and receivers can locate events without considering the origin time even using only single phase. In addition, the method can locate events with higher accuracy and has lower sensitivity on first arrival picking errors than conventional method. The method which calculates azimuths using S wave can provide reliable results when the dip between event and receiver is relatively small. However, this method shows the limitation when dip is greater than about $20^{\circ}$ in our model test.

• Korean journal of applied entomology
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• v.44 no.2
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• pp.97-108
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• 2005

Samples of water, soil, and sediment were taken from 10 streams near Andong, Korea in May 2004. To assess the degree of environmental pollution of each stream, chemical pollutants such as total notrogen (T-N), total phosphorus (T-P), chemical oxygen demand (COD), heavy metals, organophosphorus pesticides, organochlorine pesticides, and dioxin-like PCB congeners were analyzed by standard process tests or U.S. EPA methods. In addition, biomarkers originated from insect immune systems of beet armyworm, Spodoptera exigua, were used to analysis of the environmental samples. Except Waya-chun stream showing T-N content of 9.12 mg/L, most streams were contaminated with relatively low levels of overall pollutants in terms of T-N, T-P, and COD, compared to their acceptable environmental levels designated by the Ministry of Environment. Contents of Pb and Cd in samples of each stream were much lower than environmentally permissible levels. However, several times higherconcentrations of Pb and Cd were found in locations at Mi-chun, Kilan-chun, and Hyunha-chun streams, in comparison with other streams. Diazinon, parathion, and phenthoate compounds among organophosphorus pesticides were detected as concentrations of 0.19, 0.40, and $1.13\;{\mu}g/g$, respectively, from soil sample collected in the vicinity of Mi-chun stream. On the other hand, 16 organochlorine pesticides and 12 dioxin-like PCB congeners, known as endocrine disrupting chemicals, selected in this study were not found above the limit of detection. Biomarker analyses using insect immune responses indicated that Waya-chun stream was suspected as exposure to environmental pollutants. Limitation and compensation of both environmental analysis techniques are discussed.