• Analytical Science and Technology
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• v.24 no.5
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• pp.368-377
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• 2011

In this study, we analyzed the relationship between noise and air pollution from 6 residential sites from 6 districts in Seoul. The survey of all noise date obtained from 6 sites were also compared between road and nonroad area and between active (06:00-22:00) and inactive time bands (22:00-06:00). Comparison of the data between two time bands indicates that their differences are not large enough. On the other hand, if comparison of data is made by correlation analysis for road and non-road areas, strong correlations between noise levels and air pollution tend to be prevalent consistently in road area relative to the non-road area. In contrast, a correlation between noise levels and air pollution tends to decrease at the road area in inactive period relative to active period.

• The Korean Journal of Physiology and Pharmacology
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• v.2 no.1
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• pp.9-19
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• 1998

The present study was primarily carried out to characterize the properties of the spinomesencephalic tract (SMT) neurons that project from the upper cervical spinal segments to the midbrain. It was also investigated whether these neurons received convergent afferent inputs from other sources in addition to cervical inputs. Extracellular single unit recordings were made from neurons antidromically activated by stimulation of midbrain. Recording sites were located in lamina $I{\sim}VIII\;of\;C1{\sim}C3$ segments of spinal cord. Receptive field (RF) and response properties to mechanical stimulation were studied in 71 SMT neurons. Response profiles were classified into six groups: complex (Comp, n=9), wide dynamic range (WDR, n=16), low threshold (LT, n=5), high threshold (HT, n=6), deep/tap (Deep, n=10), and non- responsive (NR, n=25). Distributions of stimulation and recording sites were not significantly different between SMT groups classified upon their locations and/or response profiles. Mean conduction velocity of SMT neurons was $16.7{\pm}1.28\;m/sec$. Conduction velocities of SMTs recorded in superficial dorsal horn (SDH, n=15) were significantly slower than those of SMTs recorded in deep dorsal horn (DDH, n=18), lateral reticulated area (LRA, n=21), and intermediate zone and ventral horn (IZ/VH, n=15). Somatic RFs for SMTs in LRA and IZ/VH were significantly larger than those in SDH and DDH. Five SMT units (4 Comps and 1 HT) had inhibitory somatic RFs. About half (25/46) of SMT units have their RFs over trigeminal dermatome. Excitabilities of 5/12 cells and 9/13 cells were modulated by stimulation of ipsilateral phrenic nerve and vagus nerve, respectively. These results suggest that upper cervical SMT neurons are heterogenous in their function by showing a wide range of variety in location within the spinal gray matter, in response profile, and in convergent afferent input.

• Microbiology and Biotechnology Letters
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• v.10 no.3
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• pp.191-196
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• 1982

In order to prevent the losses of the rice by fungal deterioration during storage, fungal contaminants were isolated and identified from the grain samples (Milyang Nr.23) stored for seven months from December, 1978 to June, 1979 in silo, flat store and Tongari. Out of thirty cultures isolated from Korean paddy and brown rice samples, twenty seven species were identified, and there are eleven species of Aspergillus (A. caespitosus, A. condidus, A. chevalieri, A fischeri, A. fumigatus, A. flavus, A. nidulans, A. oryzae, A. ruber, A. sydowii, A. versicolor), five species of Penicillium (P. atramentosum, p. chrysogenum, P. cyaneofulvum, P. nototum, P. steckii), two species of each Alternaria (Al. faesiculata, Al. grisea) and Curvalaria (C, interseminata, C. tetromea), and one species of each Trichothecium roseum, Nigrospora sphaerica, Rhizopus nigricans, Fusarium spp., Mucor spp., Helminthosporium spp., and Gliocladiopsis spp. The major types of fungi grown on the surface of paddy during storage were A. flavus and A. candidus, while A. ruber and A. sydowii appeared in brown rice samples. And also A. candidus, A. versicolor and A. glacus groups were considered as major deteriorating microorganisms in stored brown and paddy rice in Korea.

• Asian Journal of Atmospheric Environment
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• v.11 no.3
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• pp.202-216
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• 2017

Nitrogen (N) is an essential macronutrient. Thus, evaluating its flows and stocks in rice paddy ecosystems provides important insights into the sustainability and environmental loads of rice production. Among the N sources of paddy fields, atmospheric deposition and irrigation inputs remain poorly understood. In particular, insufficient information is available for atmosphere-rice paddy exchange of gaseous and particulate reactive N (Nr, all N species other than molecular N) which represents the net input or output through dry deposition and emission. In this study, we assessed the N inputs via atmospheric deposition and irrigation to a Japanese rice paddy area by weekly monitoring for 2 years with special emphasis on gas and particle exchange. The rice paddy during the cropping season acted as a net emitter of ammonia ($NH_3$) to the atmosphere regardless of the N fertilizer applications, which reduced the effects of dry deposition to the N input. Dry N deposition was quantitatively similar to wet N deposition, when subtracting the rice paddy $NH_3$ emissions from N exchange. The annual N inputs to the rice paddy were 3.2 to $3.6\;kg\;N\;ha^{-1}\;yr^{-1}$ for exchange, 8.1 to $9.8\;kg\;N\;ha^{-1}\;yr^{-1}$ for wet deposition, and 11.1 to $14.5\;kg\;N\;ha^{-1}\;yr^{-1}$ for irrigation. The total N input, 22.8 to $27.5\;kg\;N\;ha^{-1}\;yr^{-1}$, corresponded to 38% to 55% of the N fertilizer application rate and 53% to 67% of the brown rice N uptake. Monitoring of atmospheric deposition and irrigation as N sources for rice paddies will therefore be necessary for adequate N management.

• Journal of Microbiology and Biotechnology
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• v.20 no.7
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• pp.1134-1139
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• 2010

This study explored the chronic effects of different doses of the triazole fungicide tebuconazole on the growth, and metabolic and enzymatic functions of the filamentous paddy field cyanobacterium, Westiellopsis prolifica Janet. The growth of the cyanobacterium was determined by an estimation of the change in pigment contents. Chlorophyll-a, carotenoids, and accessory pigments such as phycocyanin, allophycocyanin, and phycoerythrin were shown to decline over a 16-day period by a factor of 92%, 93%, 83%, 95%, and 100%, respectively, with increasing doses of the fungicide. Metabolic and enzymatic activities were also adversely affected. Over the 16 days, a gradual rise in total phenol content was recorded when Westiellopsis prolifica Janet was treated with 60 ppm of the fungicide, despite the reduction in carbohydrates, proteins, and amino acids by 96%, 92%, and 90%, respectively. Moreover, the enzymes nitrate reductase (NR), glutamine synthetase (GS), and succinate dehydrogenase (SDH) also registered reductions of 93%, 90%, and 98%, respectively. This study indicates that tebuconazole, although an important fungicide used extensively in rice fields, exhibits an inhibitory effect on the growth and metabolic activities of Westiellopsis prolifica Janet and hence possibly on other varieties as well.

• Korean Journal of Plant Taxonomy
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• v.41 no.3
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• pp.259-266
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• 2011

Elsholtzia hallasanensis, E. springia, and E. splendens var. fasciflora (Lamiaceae) were reported recently as new species or new varieties of E. splendens according to their morphological characteristics. To reappraise the taxonomic status of these additional taxa and to determine the relationships between all Korean Elsholtzia taxa except E. saxatilis, which is distributed in North Korea, molecular studies based on the nrDNA (ITS) and cpDNA (rpl16, and trnH-psbA) sequences of seven taxa of Elsholtzia and one outgroup were carried out. The molecular data support that E. angustifolia and E. minima are distinct species from E. splendens and E. ciliata, respectively, because they have several private marker genes and show monophyly. The molecular data also support that E. splendens has a very close taxonomic relationship with both E. hallasanensis and E. springia. We found that E. splendens var. fasciflora, with multiple inflorescence, was based on several private marker genes and on the monophyly of its trees, suggesting that it can be considered as a variety. Elsholtzia springia, with the same sequences and the same morphological characteristics with E. hallasanensis after transplanting, should be treated as a synonym of E. hallasanensis. Moreover, we consider the taxonomic status of E. hallasanensis as E. splendens var. hallasanensis (Y. Lee) N.S. Lee & C.S. Lee, stat. nov.

• Journal of Adhesion and Interface
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• v.3 no.2
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• pp.30-39
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• 2002

The effect of cure accelerator content on the change in crosslink density by thermal aging was studied for silica-filled natural rubber (NR) vulcanizates. Influence of silane coupling agent was also investigated. N-tert-Butyl-2-benzothiazole sulfenamide (TBBS) and bis-(3-(triethoxysilyl)-propyl)-tetrasulfide (TESPT) were used as a cure accelerator and a silane coupling agent, respectively. The crosslink density increased by thermal aging and the increasing level became larger as the aging temperature increased. The degree of crosslink density change of the vulcanizates without the silane coupling agent was larger than that of the vulcanizates containing the silane coupling agent. For the vulcanizates silane coupling agent, the activation energy for the crosslink density change decreased with increase of the cure accelerator content in the vulvanizate.

• Journal of Sasang Constitutional Medicine
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• v.30 no.2
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• pp.8-27
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• 2018

Objective This study investigated the effects of Jeoreongchajeonja-tang in a high-fat diet-induced obesity mouse model. Methods The study examined 9-week-old male mice (C57bl/6J) divided into four groups: the normal(C57bl/6J-Nr), control (high-fat diet only; HFD-CTL), positive-control (high-fat diet with Garcinia cambogia), and experimental (high-fat diet with Jeoreongchajeonja-tang; HFD-JCT) groups. After 7 weeks, the body weight, food efficiency ratio, organ weight, and visceral fat weight of the mice were measured. Blood serum tests, mRNA, liver histopathology, and epididymis adipocytes were also examined. Results Compared with the Control(HFD-CTL) group, the Experimental(HFD-JCT) group given Jeoreongchajeonja-tang showed significant reductions in absolute body weight and food efficiency ratio. The serum alanine aminotransferase, total-cholesterol, triglyceride, low-density lipoprotein (LDL)-cholesterol, high-density lipoprotein (HDL)-cholesterol, insulin-like growth factor-1, and leptin levels were significantly lower in the experimental group than in the control group. The serum adiponectin levels were significantly higher in the experimental group than in the control group. Compared with the control group, the experimental group showed significant reductions in absolute abdominal subcutaneous fat, epididymal adipose tissue, kidney adipose tissue, intestine adipose tissue, and liver, kidney and spleen adipose tissue weights. The C/EBP-${\beta}$, leptin, and SREBP1c/ADD1 mRNA expression were significantly lower in the experimental group than in the control group, while the UCP-2 and adiponectin mRNA expression were significantly higher. Compared with the control group, the experimental group showed a significant reduction in the absolute adipocyte area in the liver and epididymal adipose tissue. Conclusion Jeoreongchajeonja-tang has an anti-obesity effect. Additional clinical studies are expected.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.3
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• pp.2023-2028
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• 2013

A number of studies have indicated that Nurr1, which belongs to a novel class of orphan nuclear receptors (the NR4A family), is important for carcinogenesis. Here we investigated expression of Nurr1 protein in benign and malignant human prostate tissues and association with clinicopathologic features using immunohistochemical techniques. Moreover, we also investigated the ability of Nurr1 to influence proliferation, migration, invasion and apoptosis of human prostate cancer cells using small interfering RNA silencing. Immunohistochemical analysis revealed that the expression of Nurr1 protein was higher in prostate cancer tissues than in benign prostate tissue (P<0.001), levels being positively correlated with tumor T classification (P = 0.003), N classification (P = 0.017), M classification (P = 0.011) and the Gleason score (P = 0.020) of prostate cancer patients. In vitro, silencing of endogenous Nurr1 attenuated cell proliferation, migration and invasion, and induced apoptosis of prostate cancer cells. These results suggest that Nurr1 may be used as an indicator for prostate cancer progression and be useful for novel potential therapeutic strategies.

• The Journal of Advanced Prosthodontics
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• v.9 no.5
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• pp.328-334
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• 2017

PURPOSE. This study evaluated fracture resistance with regard to ferrule lengths and post reinforcement on endodontically treated mandibular premolars incorporating a prefabricated post and resin core. MATERIALS AND METHODS. One hundred extracted mandibular premolars were randomly divided into 5 groups (n=20): intact teeth (NR); endodontically treated teeth (ETT) without post (NP); ETT restored with a prefabricated post with ferrule lengths of either 0 mm (F0), 1 mm (F1), or 2 mm (F2). Prepared teeth were restored with metal crowns. A thermal cycling test was performed for 1,000 cycles. Loading was applied at an angle of 135 degrees to the axis of the tooth using a universal testing machine with a crosshead speed of 2.54 mm/min. Fracture loads were analyzed by one-way ANOVA and Tukey HSD test using a statistical program (${\alpha}=.05$). RESULTS. There were statistical differences in fracture loads among groups (P<.001). The fracture load of F2 ($237.7{\pm}83.4$) was significantly higher than those of NP ($155.6{\pm}74.3N$), F0 ($98.8{\pm}43.3N$), and F1 ($152.8{\pm}78.5N$) (P=.011, P<.001, and P=.008, respectively). CONCLUSION. Fracture resistance of ETT depends on the length of the ferrule, as shown by the significantly increased fracture resistance in the 2 mm ferrule group (F2) compared to the groups with shorter ferrule lengths (F0, F1) and without post (NP).