• Journal of the Korean Institute of Telematics and Electronics D
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• 제36D권1호
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• pp.38-46
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• 1999

o.25${\mu}m$ T-shaped gate P-HEMT is fabricated and used for design of X0band three stage monolithic microwave integrated circuit(MMIC) low noise amplifier(LNA). The fabricated P-HEMT exhibits an extrinsis transconductance of 400mS/mm and a drain current of 400mA/mm. The RF and noise characteristics show that the current gain cut off frequency is 65GHz and minimum noise figure(NFmin) of 0.7dB with an associated gain of 14.8dB at 9GHz. In the design of the three stage LNA, we have used the inductive series feedback circuit topology with the short stub. The effects of series feedback to the noise figure, the gain, and the stability have been investigated to find the optimal short stub length. The designed three staage LNA showed a gain of above 33dB, a noise figure of under 1.2dB, and ainput/output return loss of under 15dB and 14dB, respectively. The results show that the fabricated P-HEMT is very suitable for a X-band LNA with high gain.

• Journal of Life Science
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• 제20권2호
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• pp.314-320
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• 2010

As the nature of triathlons is competition in three successive sports, triathletes experience elevated levels of stress on the body that are absent in single-sport athletic events, and consequently there are more potential medical problems to prepare for. Triathletes can also experience problems such as hypothermia, heat illness, excessive exposure to ultraviolet radiation, musculoskeletal injuries and trauma, immunosuppression, and haemolysis. Depending on the potentiality of such above-listed problems occurring in any given race, race organizers will prepare preventative measures and treatments accordingly. Olympic distance is not the only triathlon racing distance. Sprints, which are normally around half the Olympic distance, are common distances, as well as Long (2 km swim, 80 km bike, 20 km run), Ironman (3.8 km swim, 180 km bike, 42 km run), and ultra-distance events varying in length. Races of longer duration normally result in a higher percentage of athletes experiencing the above-mentioned medical problems, as well as inducing additional health risks such as hyponatraemia. Minimizing the occurrences of serious health issues is possible through the following means: carefully preparing for the probable race-day weather conditions; proper management and organization of the race; preparing an extensive water-safety and ground-course safety plan; distributing necessary nutrition along the course; and stressing the importance for athletes to have proper knowledge concerning race nutrition, biomechanical technique, physical preparation, and utilization of safe equipment. While risks of competing in triathlon are many, the instances of such medical problems are not excessive, and the triathlon has a reputation of being a reasonably safe sport as long as athletes with high risk take added precautions.

• Korean journal of applied entomology
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• 제52권3호
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• pp.243-248
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• 2013

This study was conducted to understand the settlement process of Ascotis selenaria larvae into citrus orchards with respect to oviposition site and analysis of the spatial distribution pattern of the larvae. A. selenaria eggs were not found on citrus trees in field and green house, but not on citrus trees in the field. A. selenaria larvae showed a significant clump distribution in the greenhouse. In the open citrus field, the index of dispersion was around 1.0 in most cases, with a weak clumping degree. However, the d-statistic was between -1.96 and 1.96, indicating a statistically significant random distribution. In addition, the Green's index (a clumping index) was very low in all cases, even though the clump distribution was accepted. for most samples, the probability distribution of larval frequency in the field satisfied the probability distribution functions of Poisson (random pattern) and the negative binomial (clump pattern) distribution. In addition, the temporal distribution of the larvae in the open field showed a pattern which was formed by colonizers from outside oviposition sites. Further, the difference in larval spatial distribution between field and greenhouse orchards was discussed.

• The Journal of the Petrological Society of Korea
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• 제10권3호
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• pp.190-201
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• 2001

Isotope Dilution Mass Spectrometry(IDMS) is one of the analytical method which uses enriched isotope spikes and analyzes the abundance of element by comparison of the spectrum between spiked mass and non-spike mass. Especially, the Thermal Ion Mass Spectrometry with isotope dilution technique (in general ID-TIMS) is the most accurate method of the chemical analysis, which enables us to obtain the data better than 1% in accuracy and precision. In IDMS, enriched isotope spike is one of the most important factor in order to obtain the best data. For rare earth elements, in general, a mixture of /sup 138/La, /sup 142/Ce, /sup 145/Nd, /sup 149/Sm, /sup 151/Sm, /sup 151/Eu, /sup 157/Gd, /sup 163/Dy, /sup 167/Er, /sup 171/Yb, and /sup 176/Lu is used as composite spike. IDMS is very useful in geochronology and REE geochemistry. Especially, it is very effective in studying the “tetrad effect” of rare earth elements in natural samples.

• Asian-Australasian Journal of Animal Sciences
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• 제30권5호
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• pp.666-671
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• 2017

Objective: Aim of the current comparative study was to evaluate production outputs, reproduction efficiency and functional traits in dual-purpose Fleckvieh and Braunvieh cows, reared under temperate European conditions. Methods: A data-set from 414 Fleckvieh and 42 Braunvieh cows and 799 lactations was analysed. ID tag number, milk yield per milking session, number of steps/interval and milk conductivity were recorded and collected daily using AfiMilk 3.076 A-DU software (Afimilk Ltd., Kibbutz, Israel). Production and milk quality data were taken from the results of the official performance recordings and the reproductive outputs of cows were recorded by the research stations veterinarians. Comparisons between the two genotypes were carried out using the one way analysis of variance protocol, with categorical factor being considered the breed of cows. All the statistical inferences were carried out using Statistica software (StatSoft Inc., Tulsa, OK, USA). Results: Fleckvieh cows significantly outperformed ($p{\leq}0.05$) the Braunvieh herd, with average milk yields of $5,252.1{\pm}35.79kg$ and $4,897.6{\pm}128.94kg$, respectively. Age at first calving was significantly ($p{\leq}0.01$) influenced by the breed, with Fleckvieh heifers being more precocious ($32.8{\pm}0.29mo$) compared to those of Braunvieh breed ($35.7{\pm}0.84mo$). Reproduction efficiency as defined by the number of inseminations per gestation, calving interval, dystocia, days dry and days open, was not influenced by genotype (p>0.05). Incidences of sub-clinical mastitis, clinical mastitis, lameness and abortions were not influenced by the breed factor (p>0.05). Stay-ability of cows was significantly ($p{\leq}0.001$) influenced by genotype, with Braunvieh cows having an average age at culling of $117.88{\pm}11.78$ months compared to $90.88{\pm}2.89$ months in Fleckvieh. Conclusion: Overall, results have shown that genotype significantly influenced milk yield, age at first calving and longevity.

• Herbal Formula Science
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• 제14권1호
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• pp.105-119
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• 2006

Objectives & Methods : This present study was performed to investigate the effect of Hwadamtongrak-Tang extract (HTT) on the regulation of cerebral hemodynamics in terms of regional cerebral blood flow (rCBF) and mean arterial blood pressure (MABP)] in normal and cerebral ischemic rats. Also the effects of HTT on changes in local blood flow, inhibition of LD H activity in neuronal cells, and levels of cytokine production in the serum were determined in the ischemic rat model. The major findings are summarized below. Results : 1. HTT significantly increased rCBF in a dose-dependent manner, but MABP was not changed by HTT treatment. These results suggest that HTT may increase rCBF by dilating cerebral arterial diameter. 2. HTT-induced increase in rCBF was blocked by pretreatment with cyclooxygenase inhibitor indomethacin (IDN, 1 mg/kg, i.p.) and MABP was significantly increased by ID N. 3. Pretreatment of methylene blue $(MTB,\;10\;{\mu}g/kg,\;i.p.)$, an inhibitor of guanylate cyclase, significantly decreased both rCBP and MABP in HTT-treated rats. 4. HTT treatment significantly increased rCBP to a stable level during the period of cerebral reperfusion. 5. HTT significantly inhibited LD H activity in neuronal cells, suggesting a neuroprotection by HTT. 6. Serum interleukin $(IL)-1{\beta}$ and tumor necrosis factor $(TNF)-{\alpha}$ levels were significantly decreased in the femoral artery 1 hr after middle cerebral arterial occlusion in HTT-treated rats. IL-10 levels in the serum were significantly increased by HTT treatment whereas transforming growth factor $(TGF)-{\beta}$ levels were similar between HTT-treated and control groups. 7. Serum interleukin $(IL)-1{\beta}$ and tumor necrosis factor $(TNF)-{\alpha}$ levels were significantly decreased in the femoral artery 1 hr after reperfusion in HTT-treated rats. Serum IL-10 levels were significantly decreased in HTT-treated rats compared with the control group, and no significant changes in $(TGF)-{\beta}$ in the serum were observed by HTT treatment. Conclusions: The present data suggest that HTT may have an anti-ischemic effect via the improvement of cerebral hemodynamics and thus protect the brain from ischemic damage.

• The Korean Journal of Pesticide Science
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• 제2권1호
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• pp.59-64
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• 1998

In order to elucidate the leaching behaviour of the herbicide bentazon in soil, soil columns(5cm ID ${\times}$ 34 cm L) were packed with three different soils up to 30 cm height, followed by the treatment of [$^{14}C$]bentazon, and rice plants(Oryza sativa L.) were grown for 9 weeks on these columns, with the columns without growing rice plants as the control for comparison. The amounts of $^{14}C$ activities percolated were about 92% of the originally applied $^{14}C$ irrespective of the physicochemical properties of the soils in the absence of rice plants, whereas $21{\sim}50%$ of the originally applied $^{14}C$ was percolated in the presence of rice plants, suggesting that the amounts of $^{14}C$ leached decreased remarkably in rice-cultivating soils. Bentazon leached faster in soil with higher pH and with lower organic matter content in the presence of growing rice plants. The amounts of $^{14}CO_{2}$ evolved from the soil columns were less than 0.2% of the originally applied $^{14}C$. Smaller amounts of $^{14}C$ were translocated into shoots via roots in soils with higher organic matter content. $^{14}C$ activities distributed into the aqueous phase of the leachate collected from the soil columns increased with leaching period and by rice cultivation, whereas the physico-chemical properties of soils did not exhibit any effect. The amounts of soil-bound residues increased remarkably by cultivating rice plants.

• Journal of Internet Computing and Services
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• 제8권1호
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• pp.33-45
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• 2007

Using switches and sensors informing the current on or off state, this paper suggests a sleeping control and remote monitoring system that not only can recognize the sleeping situations but also can control for keeping an appropriate sleeping situation remotely, And we show an example that this system is applied to the healthcare sleeping mat, Our system comprises the following 3 parts: a part for detecting the sleeping situations, a part for extracting sensing data and sending/receiving the relating situated data, and a part controlling and monitoring the all of sleeping situations. In details, in order to develop our system, we used the touch and pressure-sensitive sensors with On/Off functions for a purpose of the first part, The second part consists of the self-developed embedded board with the socket based communication as well as extracting real-time sensing data. And the third part is implemented by service modules for providing controlling and monitoring functions previously described. Finally, these service modules are implemented by the TMO scheme, one of real-time object-oriented programming models and the communications among them is supported using the TMOSM of distributed real-time middleware.

• Toxicological Research
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• 제32권1호
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• pp.81-87
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• 2016

Aflatoxin B1 (AFB1) is produced by Aspergillus flavus growing in feedstuffs. Early detection of maize contamination by aflatoxigenic fungi is advantageous since aflatoxins exert adverse health effects. In this study, we report the development of an optimized conventional PCR for AFB1 detection and a rapid, sensitive and simple screening Real-time PCR (qPCR) with SYBR Green and two pairs of primers targeting the aflR genes which involved aflatoxin biosynthesis. AFB1 contaminated maize samples were divided into three groups by the toxin concentration. Genomic DNA was extracted from those samples. The target genes for A. flavus were tested by conventional PCR and the PCR products were analyzed by electrophoresis. A conventional PCR was carried out as nested PCR to verify the gene amplicon sizes. PCR-RFLP patterns, obtained with Hinc II and Pvu II enzyme analysis showed the differences to distinguish aflatoxin-producing fungi. However, they are not quantitative and need a separation of the products on gel and their visualization under UV light. On the other hand, qPCR facilitates the monitoring of the reaction as it progresses. It does not require post-PCR handling, which reduces the risk of cross-contamination and handling errors. It results in a much faster throughout. We found that the optimal primer annealing temperature was $65^{\circ}C$. The optimized template and primer concentration were $1.5{\mu}L\;(50ng/{\mu}L)$ and $3{\mu}L\;(10{\mu}M/{\mu}L)$ respectively. SYBR Green qPCR of four genes demonstrated amplification curves and melting peaks for tub1, afIM, afIR, and afID genes are at $88.0^{\circ}C$, $87.5^{\circ}C$, $83.5^{\circ}C$, and $89.5^{\circ}C$ respectively. Consequently, it was found that the four primers had elevated annealing temperatures, nevertheless it is desirable since it enhances the DNA binding specificity of the dye. New qPCR protocol could be employed for the determination of aflatoxin content in feedstuff samples.

• Korean Journal of Community Nutrition
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• 제12권3호
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• pp.272-283
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• 2007

This study was performed to delineate the relationship between lifestyle and nutritional risk factors associated with hypertension in representative middle-aged Korean population. Hypertension in this study is defined as hypertensive ($SBP{\geq}140mmHg\;or\;DBP{\geq}90mmHg$) adults without recognition of a disease state before a health exam. With data from the 1998 and 2001 National Health and Nutritional Survey, nutrient intakes of 6,112 adults, 40-64 years of age were calculated using food composition database and matched with health examination records by individual ID. After excluding those with extreme intake values, the number of final subjects included in the analysis was 5,200 (male 2,458, female 2,742). Using logistic regression method, socio-demographic data, lifestyle factors, and nutrient intakes were analyzed. Risky factors for hypertension revealed in this study were age, sex, BMI over 23, waist circumference, alcohol intake of more than 16g (male) or 8g (female). Regarding nutrient intakes, the intakes of highest quartile for energy (${\geq}2363.0kcal$) and protein (${\geq}90.2g$) were significantly associated with higher risk of hypertension after adjusting for age, sex, and other socio-demographic factors (OR=1.312(1.046-1.711), OR=1.488(1.194-1.854), respectively)). Although high intakes of sodium (${\geq}6604.0mg$) and phosphorus seemed to be risk factors of hypertension also before energy adjustment (OR=1.278(1.034-1.581), OR=1.280(1.024-1.600), respectively), only high intakes of energy and protein remained significant after adjustment. This study revealed that modifying risky lifestyles and dietary patterns, especially high energy intake, high protein intake, and high alcohol drinking, in middle-aged Korean adults could result in a prevalence decrease and/or prevention of hypertension.