• The korean journal of orthodontics
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• 제32권4호
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• pp.275-291
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• 2002

Of various factors indicated for effective use of straight wire appliances, there was a great lack of studies both domestic and international about the curvatures of tooth crowns. This study was performed to investigate the labio/buccal clinical crown curvatures of Korean permanent teeth. For this study, three-dimensional laser scanning was performed on 36 dental casts with normal anatomic structures. Andrews plane and Facial axis of clinical crown (FACC) were designated as horizontal and vertical reference planes respectively. 2 or 3 lines, 1mm apart, were drawn superior, inferior, left and right of these reference planes. A three-dimensional coordinate table was made for points formed by crossing these lines, and averages of each coordinate point on the 36 dental casts were obtained. The curvature equation was made using three-dimensional coordinate points (x,y,z) and by this curvature equation, the curve ratio of each tooth was obtained. Curve ratio changes of each section of teeth were calculated by curve ratios of simplified curves. These two dimensional curves were simplified horizontally and vertically Conclusions for this study are as follows. 1. The basic data of labial and buccal clinical crown curvatures were obtained about Korean permanent teeth. 2. No significant difference was found between male and females. 3. Individual tooth characteristics 1) In maxillary central incisors, the difference in the curve ratio between the gingival and incisal sides was greater than for the other teeth. And the gingival side showed a greater curve ratio. 2) Maxillary canines showed more curvatures in the mesio-occlusal surface than the other surfaces. 3) In maxillary $1^{st}$ premolars, more curvatures were found in mesio-occlusal and disto-gingival surface, thus showing a twisted crown surface, but in maxillary $2^{nd}$ premolars, the crown curvatures of mesial and distal ends became parallel to each other. 4) No significant difference in crown curvatures was found between mandibular central and lateral incisors. 5) Occluso-gingival curvatures of mandibular$2^{nd}$ premolar turned out to be more rounded than mandibular $1^{st}$ premolars or maxillary $2^{nd}$ premolars. From the above conclusions, it can be deduced that the same bracket bases can be used for mandibular central and lateral incisors. But for maxillary $1^{st}\;and\;2^{nd}$ premolars and for mandibular $1^{st}\;and\;2^{nd}$ premolars, because crown curvatures showed significant differences, when making bracket bases there is ample reason to make bracket base curves differently for each type of tooth.

• Korean Journal of Environment and Ecology
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• 제22권6호
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• pp.679-690
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• 2008

The objectives of this study are to investigate and analyze the vegetation structure and population dynamics of Berchemia racemosa habitats in the Weolmyung park in Gunsan city, and base on that to seek the ecological habitat conservation plan for the Berchemia racemosa. In results, the Berchemia racemosa habitats are located at $81{\sim}93$ meters above the sea level, in steep seaside slope of a mountain. The soil texture are silt loam mainly and soil pH were $4.1{\sim}5$. The vascular plants in the Berchemia racemosa habitats has been analyzed as 61 taxa; 33 families, 51 genera, 54 species, 6 varieties, and 1 forms. Berchemia racemosa as a Specific plant species by floral region was the class V. Berchemia racemosa habitats were classified into 7 vegetation communities of Quercus serrata community(A1), Alnus firm a community(A2), Platycarya strobilacea community(A3), Robinia pseudoacacia community(A4) and 3 Pinus densiflora communities(B1, B2, B3). The importance value of Berchemia racemosa were 30%(A1), 15%(A2), 27%(A3), 65%(A4), 18%(B1), 45%(B2) and 35%(B3) on shrubs layer and 12, 27, 20, 18, 11, 18, 21 % on herb layer. The constant companion species with Berchemia racemosa were Stephanandra incisa and Ligustrum obtusifolium. Total 103 populations appear in the 7 Berchemia racemosa habitats. Their spatial distribution pattern were clumped for the most part. The average height was 133cm, the root color diameter was 4.4cm and the ramification branch number was 9.4. From the results of this study, it is suggested the continued monitoring and the active protection measures for the Berchemia racemosa habitats.

• Journal of the Korean Society of Food Science and Nutrition
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• 제46권3호
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• pp.298-305
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• 2017

Atopic dermatitis is a chronic, relapsing inflammatory skin disease. This study aimed to investigate the therapeutic benefits of Aronia melanocarpa (AM) and Moringa oleifera seed extract (MO) on experimental atopic dermatitis. We examined the effects of AM or MO and their combination on 2,4-dinitrochlorobenzene (DNCB)-induced atopic dermatitis in BALB/c mice as well as tumor necrosis factor $(TNF)-{\alpha}$ and interferon $(IFN)-{\gamma}-stimulated$ HaCaT keratinocytes. Mice were orally treated with extract during repeated application of DNCB to shaved dorsal skin. Our results show that treatment with AM and MO in combination reduced histological manifestations such as epidermal hyperplasia and inflammatory cell infiltration. Furthermore, it significantly decreased skin thickness and serum immunoglobulin E (IgE) level compared to the AM or MO alone treated group. Combined extract of AM and MO suppressed expression of $TNF-{\alpha}/IFN-{\gamma}-induced$ T helper 2 (Th2) chemokines such as thymus and activation-regulated chemokine and macrophage-derived chemokine. To sum up, combination of AM and MO suppressed the inflammatory response and serum IgE as an indicator of several allergic diseases in DNCB-induced experimental atopic dermatitis and Th2 chemokine expression in HaCaT cells. This result suggests that combination of AM and MO could be a valuable strategy to improve atopic dermatitis.

• Proceedings of the Korean Vacuum Society Conference
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• 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
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• pp.388-388
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• 2016

Chemical mist deposition (CMD) of poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) was investigated with cavitation frequency f, solvent, flow rate of nitrogen, substrate temperature $T_s$, and substrate dc bias $V_s$ as variables for efficient PEDOT:PSS/crystalline (c-)Si heterojunction solar cells (Fig. 1). The high-speed camera and differential mobility analysis characterizations revealed that average size and flux of PEDOT:PSS mist depend on f, solvent, and $V_s$. The size distribution of mist particles including EG/DI water cosolvent is also shown at three different $V_s$ of 0, 1.5, and 5 kV for a f of 3 MHz (Fig. 2). The size distribution of EG/DI water mist without PEDOT:PSS is also shown at the bottom. A peak maximum shifted from 300-350 to 20-30 nm with a narrow band width of ~150 nm for PEDOT:PSS solution, whose maximum number density increased significantly up to 8000/cc with increasing $V_s$. On the other hand, for EG/water cosolvent mist alone, the peak maximum was observed at a 72.3 nm with a number density of ~700/cc and a band width of ~160 nm and it decreased markedly with increasing $V_s$. These findings were not observed for PEDOT:PSS/EG/DI water mist. In addition, the Mie scattering image of PEDOT:PSS mist under white bias light was not observed at $V_s$ above 5 kV, because the average size of mist became smaller. These results imply that most of solvent is solvated in PEDOT:PSS molecule and/or solvent is vaporized. Thus, higher f and $V_s$ generate preferentially fine mist particle with a narrower band width. Film deposition occurred when $V_s$ was impressed on positive to a c-Si substrate at a Ts of $30-40^{\circ}C$, whereas no deposition of films occurred on negative, implying that negatively charged mist mainly provide the film deposition. The uniform deposition of PEDOT:PSS films occurred on textured c-Si(100) substrate by adjusting $T_s$ and $V_s$. The adhesion of CMD PEDOT:PSS to c-Si enhanced by $V_s$ conspicuously compared to that of spin-coated film. The CMD PEDOT:PSS/c-Si solar cell devices on textured c-Si(100) exhibited a ${\eta}$ of 11.0% with the better uniformity of the solar cell parameters. Furthermore, ${\eta}$ increased to 12.5% with a $J_{sc}$ of $35.6mA/cm^2$, a $V_{oc}$ of 0.53 V, and a FF of 0.67 with an antireflection (AR) coating layer of 20-nm-thick CMD molybdenum oxide $MoO_x$ (n= 2.1) using negatively charged mist of 0.1 wt% 12 Molybdo (VI) phosphoric acid n-Hydrate) $H_3(PMo_{12}O_40){\cdot}nH_2O$ in methanol. CMD. These findings suggest that the CMD with negatively charged mist has a great potential for the uniform deposition of organic and inorganic on textured c-Si substrate by adjusting $T_s$ and $V_s$.

• Korean Journal of Agricultural Science
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• 제41권4호
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• pp.415-424
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• 2014

This study was carried out to determine the effect of storage condition, such as temperature or relative humidity (RH) in home-style refrigerator, on the change of quality traits and storage characteristics of Hanwoo M. longissimus to find out the condition for prolongation of shelf-life with maintaining the meat quality for consumers. Samples were sliced in $1{\pm}0.2cm$ thickness, and packed in foamed polystyrene tray with linear low-density polyethylene (LLD-PE) film to simulate the pre-packed Hanwoo loin sold in retail market, then stored in home-style refrigerator ($5^{\circ}C$/17% RH, Control), and chambers of $5^{\circ}C$/55% RH (T1), $5^{\circ}C$/85% RH (T2), and $-1^{\circ}C$/99% RH (T3), respectively. Quality traits (color, pH, water holding capacity, shear force and grilling loss) and storage characteristics (thiobarbituric acid reactive substances, volatile basic nitrogen and total microbes) were measured at 1, 4, 7, 14 and 21 days after storage. Lightness of Hanwoo loin stored in T1, T2 and T3 were higher than that of control until 14 days of storage, however at the end of storage (21 days) control showed significantly higher than other treatments (p<0.05). Redness and Yellowness of Hanwoo loin samples stored in T1 and T3 were significantly higher than others during all storage period (p<0.05). The water holding capacity (WHC) of control was significantly higher than others until 14 days of storage (p<0.05), however, Hanwoo loin stored in T2 was the highest ($63.64{\pm}7.62kg/cm^2$) at 21 days of storage. Hanwoo loin stored in T1 showed significantly lower shear force than others during all storage period (p<0.05). There was no consistent tendency in pH and grilling loss during storage in all treatments. Hanwoo loin stored in T1 showed lower TBARS value than others during storage period, however there was a rapid increase to $0.34{\pm}0.27mg$ malonaldehyde/kg meat at 21 days of storage. And, all the treated samples (from T1 to T3) showed significantly lower VBN values at 21 days of storage (p<0.05). The population of total aerobic microbes were significantly increased in all treatments as storage period increasing, and the population of T3 ($2.28{\pm}0.57logCFU/g$) was the lowest at 21 days of storage (p<0.05). From those results, it could be predicted the better storage condition to maintain the meat quality and prolong the shelf-life of Hanwoo loin by lowering the temperature and adjusting the humidity about 55%.

• KDI Journal of Economic Policy
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• 제14권1호
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• pp.147-165
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• 1992

This paper analyzes the macroeconomic effects of elections on the Korean economy and their future ramifications. It measures the shocks to the Korean economy caused by elections by taking the average of sample forecast errors from four major elections held in the 1980s. The seven variables' Bayesian Vector Autoregression Model which includes the Monetary Base, Industrial Production, Consumption, Consumer Price, Exports, and Investment is based on the quarterly time series data starting from 1970 and is updated every quarter before forecasts are made for the next quarter. Because of this updating of coefficients, which reflects in part the rapid structural changes of the Korean economy, this study can capture the shock effect of elections, which is not possible when using election dummies with a fixed coefficient model. In past elections, especially the elections held in the 1980s, $M_2$ did not show any particular movement, but the currency and base money increased during the quarter of the election was held and the increment was partly recalled in the next quarter. The liquidity of interest rates as measured by corporate bond yields fell during the quarter the election and then rose in the following quarter, which is somewhat contrary to the general concern that interest rates will increase during election periods. Manufacturing employment fell in the quarter of the election because workers turned into campaigners. This decline in employment combined with voting holiday produce a sizeable decline in industrial production during the quarter in which elections are held, but production catches up in the next quarter and sometimes more than offsets the disruption caused during the election quarter. The major shocks to price occur in the previous quarter, reflecting the expectational effect and the relaxation of government price control before the election when we simulate the impulse responses of the VAR model, imposing the same shocks that was measured in the past elections for each election to be held in 1992 and assuming that the elections in 1992 will affect the economy in the same manner as in the 1980s elections, 1992 is expected to see a sizeable increase in monetary base due to election and prices increase pressure will be amplified substantially. On the other hand, the consumption increase due to election is expected to be relatively small and the production will not decrease. Despite increased liquidity, a large portion of liquidity in circulation being used as election funds will distort the flow of funds and aggravate the fund shortage causing investments in plant and equipment and construction activities to stagnate. These effects will be greatly amplified if elections for the head of local government are going to be held this year. If mayoral and gubernatorial elections are held after National Assembly elections, their effect on prices and investment will be approximately double what they normally will have been have only congressional and presidential elections been held. Even when mayoral and gubernatorial elections are held at the same time as congressional elections, the elections of local government heads are shown to add substantial effects to the economy for the year. The above results are based on the assumption that this year's elections will shock the economy in the same manner as in past elections. However, elections in consecutive quarters do not give the economy a chance to pause and recuperate from past elections. This year's elections may have greater effects on prices and production than shown in the model's simulations because campaigners' return to industry may be delayed. Therefore, we may not see a rapid recall of money after elections. In view of the surge in the monetary base and price escalation in the periods before and after elections, economic management in 1992 should place its first priority on controlling the monetary aggregate, in particular, stabilizing the growth of the monetary base.

• Tuberculosis and Respiratory Diseases
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• 제63권4호
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• pp.331-336
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• 2007

Background: Although pulmonary tuberculosis (TB) is a respiratory disease, the presence of Mycobacterium tuberculosis (Mtb) DNA or Mtb itself has been reported in the peripheral blood (PB) of several patients with pulmonary TB. Additionally, it was recently announced that active pulmonary TB patients donated PB, and that this blood was then transfused to other individuals in Korea. Methods: Sixty-nine patients with bacteriologically-confirmed pulmonary TB (35), non-tuberculous mycobacterial (NTM) lung disease (6), and other lung diseases (28) were enrolled in this study, which was conducted to determine if Mtb DNA could be detected in the PB by PCR. In addition, 10 pulmonary TB patients with high-burden bacilli were also enrolled in this study for the culture of Mtb in PB. Results: PCR detected the presence of Mtb in 22.8% (8/35) of the pulmonary TB patients, in 16.7% (1/6) of the patients with NTM lung disease, and in none of the patients with other diseases (0%). In addition, no Mtb was cultured from the PB of the 10 pulmonary TB patients. Conclusion: Although Mtb DNA was detected in the PB of some patients with pulmonary TB, viable Mtb was not isolated from the PB of those patients, which indicates that patients that viable Mth may not be transmitted via trasfusion of blood of pulmonary TB patients.

• Journal of Embryo Transfer
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• 제19권2호
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• pp.113-119
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• 2004

The purpose of the present study was to examine whether collection time affects results of oocyte recovery from superovulated goats. Fiftyty-one mature Korean native goats, maintained in a pen under natural day length and fed hay ad libitum, were pretreated with progestagen impregnated CIDR for 10 days and then the goats were divided into two groups. One group of the goats received a single intramuscular injection of 1,000 IU PMSG on Day 8 of CIDR insertion. The other group of the goats received twice daily intramuscular injections of a total of 70 mg FSH for 3 days from Day 8 of CIDR. All the gonadotropin treated goats were injected with 10 mg $PGF_{2\alpha}$ on Day 8 and 400 IU hCG in the afternoon on Day 10. For oocyte recovery, donor goats were fasted 24 h before operation. Anesthesia was induced by intravenous injection of 2% xylazine(0.2 mg/kg body weight) and ketamin(11 mg/kg body weight). In vivo oocytes were recovered by follicle aspiration or oviduct flushing at 29 to 34, 35 to 40 and 41 to 50 h after hCG injection through mid-ventral incision. There was no significant difference in the mean number of CL and oocytes recovered. Oocyte collection at 29 to 40 h after hCG increased(P<0.05) the recovery rate of ovulated oocytes in oviducts compared to 41 to 50 h. The same results were also observed in the recovery of follicular oocytes. Oocyte grade was not affected by collection time. When oocytes were collected from follicular oocytes at 41 to 50 h after hCG, the recovery rate of Grade II oocytes was the lowest(P<0.05). From these results, it is suggested that oocyte recovery at 35 to 40 h after hCG will be successful for further use.

• Journal of Food Hygiene and Safety
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• 제24권3호
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• pp.232-237
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• 2009

This study was conducted to develop a model for describing the effect of storage temperature (4, 10, 15, 20, 25, 30 and $35^{\circ}C$) on the growth of Escherichia coli O157 : H7 in ready-to-eat (RTE) lettuce treated with or without (control) alkaline electrolyzed water (AIEW). The growth curves were well fitted with the Gompertz equation, which was used to determine the specific growth rate (SGR) and lag time (LT) of E. coli O157 : H7 ($R^2$ = 0.994). Results showed that the obtained SGR and LT were dependent on the storage temperature. The growth rate increased with increasing temperature from 4 to $35^{\circ}C$. The square root models were used to evaluate the effect of storage temperature on the growth of E. coli O157 : H7 in lettuce samples treated without or with AIEW. The coefficient of determination ($R^2$), adjusted determination coefficient ($R^2_{Adj}$), and mean square error (MSE) were employed to validate the established models. It showed that $R^2$ and $R^_{Adj}$ were close to 1 (> 0.93), and MSE calculated from models of untreated and treated lettuce were 0.031 and 0.025, respectively. The results demonstrated that the overall predictions of the growth of E. coli O157: H7 agreed with the observed data.

• Applied Microscopy
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• 제30권4호
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• pp.347-355
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• 2000

Zinc is one of the most abundant oligoelements in the living cell. It appears tightly bound to some metalloproteins and nucleic acids, loosely bound to some metallothioneins or even as free ion. Small amounts of zinc ions (in the nanomolar range) regulate a plentitude of enzymatic proteins, receptors and transcription factors, thus rolls need accurate homeostasis of zinc ions. Zinc is an essential catalytic or structural element of many proteins, and a signaling messenger that is released by neural activity at many central excitatory synapses. Growing evidences suggest that zinc may also be a key mediator and modulator of the neuronal death associated with transient global ischemia and sustained seizures, as well as perhaps other neurological disease stoles. Some neurons have developed mechanisms to accumulate zinc in specific membrane compartment ('vesicular zinc') which can be evidenced using histochemical techniques. Substances giving a bright colour or emitting fluorescence when in contact with divalent metal ions are currently used to detect them inside cells; their use leads to the so called 'direct' methods. The fixation and precipitation of metal ions as insoluble salt precipitates, their maintenance along the histological process and, finally, their demonstration after autometallographic development are essential steps for other methods, the so called 'indirect methods'. This study is a short report on the autometallograhical approaches for zinc detection in the central nervous system (CNS) by means of a modified selenium method.