• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.31 no.2
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• pp.137-142
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• 2005

To analyze the developmental changes in soma diameters of digastric motoneurons, wheat-germ agglutinin conjugated horseradish peroxidase (WGA-HRP) was injected into the digastric muscle and visualized the retrogradely HRP-labeled motoneurons through tungstate/tetramethylbenzidine (TMB) and following diaminobenzidine (DAB) reactions. The results obtained from Sprague-Dawley rats at postnatal days 1 (P1), 10 (P10) and 30 (P30) indicated as follows: firstly, soma diameters of digastric motoneurons showed unimodal distribution in all postnatal days examined; secondly, the period of P1 to P10 (period 1) showed about 2 times faster growth rate than that of P10 to P30 (period 2); thirdly, the smallest soma examined in each postnatal day exhibited slower growth rate with that of the largest one (increase ratio in soma diameters from P1 to P30, smallest vs. largest = 1.62 : 1.93); Finally, relative growth rates a day showed again that period 1 had faster growth rate than that of period 2. Consequently, developmental changes in soma diameters of digastric motoneurons resulted in very different growth rates between both periods. This implies that the growth of the soma is almost completing within P10 and thereafter growing slowly. The period 1 and 2 are corresponding to sucking and sucking/masticatory period, respectively. Therefore present study providing morphological changes in soma diameters of digastric motoneurons suggests that both periods and their different growth rates of the motoneurons in each period may closely be related with each other.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.43 no.11 s.353
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• pp.37-47
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• 2006

This work proposes a 10b 25MS/s $0.8mm^2$ 4.8mW 0.13um CMOS A/D Converter (ADC) for high-performance wireless communication systems such as DVB, DAB and DMB simultaneously requiring low voltage, low power, and small area. A two-stage pipeline architecture minimizes the overall chip area and power dissipation of the proposed ADC at the target resolution and sampling rate while switched-bias power reduction techniques reduce the power consumption of analog amplifiers. A low-power sample-and-hold amplifier maintains 10b resolution for input frequencies up to 60MHz based on a single-stage amplifier and nominal CMOS sampling switches using low threshold-voltage transistors. A signal insensitive 3-D fully symmetric layout reduces the capacitor and device mismatch of a multiplying D/A converter while low-noise reference currents and voltages are implemented on chip with optional off-chip voltage references. The employed down-sampling clock signal selects the sampling rate of 25MS/s or 10MS/s with a reduced power depending on applications. The prototype ADC in a 0.13um 1P8M CMOS technology demonstrates the measured DNL and INL within 0.42LSB and 0.91LSB and shows a maximum SNDR and SFDR of 56dB and 65dB at all sampling frequencies up to 2SMS/s, respectively. The ADC with an active die area if $0.8mm^2$ consumes 4.8mW at 25MS/s and 2.4mW at 10MS/s at a 1.2V supply.

• Development and Reproduction
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• v.12 no.2
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• pp.159-168
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• 2008

Nanog is a newly identified member of the homeobox family of DNA binding transcription factors that functions to maintain the undifferentiated state of stem cells. However, molecular mechanisms underlying the function of Nanog remain largely unknown. To elucidate the regulatory roles of Nanog involved in maintenance of P19 embryonal carcinoma (EC) stem cells, we transfected three small interfering RNA (siRNA) duplexes targeted against different regions of the Nanog gene into P19 cells. The Nanog siRNA-100 duplexes effectively decreased the expression of Nanog up to 30.7% compared to other two Nanog siRNAs, the Nanog siRNA-400 (67.9 %) and -793 (53.0%). When examined by RT-PCR and real-time PCR, the expression of markers for pluripotency such as Fgf4, Oct3/4, Rex1, Sox1 and Yes was downregulated at 48 h after transfection with Nanog siRNA-100. Furthermore, expression of the ectodermal markers, Fgf5 and Isl1 was reduced by Nanog knockdown. By contrast, the expression of other markers for pluripotency such as Cripto, Sox2 and Zfp57 was not affected by Nanog knockdown at this time. On the other hand, the expression of Lif/Stat3 pathway molecules and of the endoderm markers including Dab2, Gata4, Gata6 and the germ cell nuclear factor was not changed by Nanog knockdown. The results of this study demonstrated that the knockdown of Nanog expression by RNA interference in P19 cells was sufficient to modulate the expression of pluripotent markers involved in the self-renewal of EC stem cells. These results provide the valuable information on potential downstream targets of Nanog and add to our understanding of the function of Nanog in P19 EC stem cells.

• The Korean Journal of Pharmacology
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• v.8 no.2
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• pp.21-26
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• 1972

Zea mays Linne, which belongs to Graminae family, has been ordinarily used as edibles and fodder. Its stigma, Maydis Stigma, has been discarded without any special application with the exception of being used as diuretic in the sphere of Chinese medicine. Moreover, the pharmacological research toward Maydis Stigma as a medicinal herb has not been regretfully undertaken at all. The authors hereby paid attention to this point of view and made experiment to find out whether the water extract of Maydis Stigma might possess some pharmacological effect on the blood pressure of the rats or not. $LD_{50}$ to the mice was determined and the experiment was performed making the use of several agents related to the blood pressure such as atropine, Avil, dichloroisoproterenol and hexamethonium. The blood pressure of the rats and rabbits was recorded with the equipment of polygraph (Grass model 7 DAB) and its accessory, Statham pressure transducer. The results of the experiment are as follows. 1. $LD_{50}$ to the mice weighing 20g is determined 1,125 mg/kg. 2. The blood pressure manifests the gradual decrease by the rate of $-15.50{\pm}3.32,\;-22.14{\pm}8.73$ and $-46.25{\pm}5.17\;mmHg$ in proportion to ZW 25, 50 and 150mg/kg administered to the rats. 3. The blood pressure also manifests the same gradual decrease in proportion to ZW administered to the rabbits. 4. It is of significant difference to manifest the increase of $+5.14{\pm}4.65\;mmHg$ in the rats pretreated with atropine as compared with $-22.14{\pm}8.73\;mmHg$ of control group when administered each ZW 50mg/kg. 5. The administration of ZW 50 mg/kg to the rats pretreated with Avil, dichloroisoproterenol and hexamethonium does not manifest the significant difference in comparison with the control group.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.39 no.5
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• pp.65-73
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• 2002

In this paper, we propose and verify an implementation method for a single-chip 2048 complex point FFT/IFFT in terms of sequential data processing. For the sequential processing of 2048 complex data, buffers to store the input data are necessary. Therefore, DRAM-like pipelined commutator architecture is used as a buffer. The proposed structure brings about the 60% chip size reduction compared with conventional approach by using this design method. The 16-point FFT is a basic building block of the entire FFT chip, and the 2048-point FFT consists of the cascaded blocks with five stages of radix-4 and one stage of radix-2. Since each stage requires rounding of the resulting bits while maintaining the proper S/N ratio, the convergent block floating point (CBFP) algorithm is used for the effective internal bit rounding and their method contributed to a single chip design of digital audio broadcasting system.

• Journal of the Korean Chemical Society
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• v.24 no.4
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• pp.280-287
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• 1980

The interactions of chemical carcinogens, such as polycyclic aromatic hydrocarbons, dimethylaminoazobenzene (DAB) and its derivatives and heterocyclic compounds with tissue components, especially with deoxyribonucleic acid (DNA), were examined by means of simple Huckel method. Assuming that the formations of a loose molecular complex between the carcinogens and the tissue components are the first step of chemical carcinogenesis, the most proble orientation between the chemical carcinogens and adenine-thymine (A=T) pair or guanine-cytosine $(G\equivC)$ pair is determined. It has been found that, in the case of the formation of molecular complex between chemical carcinogens and A=T pair, the two atoms of K-region of the carcinogens and the atom of L-region in the proximity of their K-region are combined correspondingly with C-l' carbon atom in the sugar that is attached to thymine, N-1 nitrogen atom and C-5 carbon atom in the thymine part of A=T pair, while, in the case of that between the carcinogens and $G\equivC$ pair, the above three atoms of the carcinogens are combined correspondingly with C-8 carbon atom, N-9 nitrogen atom and N-3 nitrogen atom in the guanine part of $G\equivC$ pair.

• Journal of architectural history
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• v.22 no.5
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• pp.23-35
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• 2013

This study aims to investigate the architectural characteristics of the Da-bo stupa by examining the correlation among architectural languages and by studying the features of its architectural components and transitional changes shown in Da-bo stupa line drawings in Dunhuang Mogao Grottes. The results are as follows. 1st, the Da-bo stupa of Dunhuang faithfully follows the sutra of lotus, and although the form changes, the fundamental essence of Bo-tap-yong-chul and two seated Buddhas provided by the Gyun-bo-tap-pum in the sutra of lotus is consistent. 2nd, the pagoda body can be periodically divided into parasol, stupa, and royal palace types. The parasol type has an incomplete tower body, which makes distinguishing each of its architectural components difficult. The stupa type appeared between the early (AD 618-712) and middle (AD 766-835) Tang dynasty. It combines the form of Indian stupa type and East Asian wood structural architecture. The royal palace type, which appeared between the peak period of the Tang (713-765) and Sung Dynasties, shows the standardized pattern of the Da-bo stupa described as two seated Buddhas and Bo-tap-yong-chul. 3rd, the use of a stylobate does not appear in the early construction of Da-bo stupa, only in the later period, in the form of high pillars. Forms include many Su-mi-jwah and three-way stairways and Dab-do, but as time passes, the forms are simplified to the form of high pillars. 4th, the purpose of early Da-bo stupa was to provide space for Da-bo-yu-rae of Gyun-bo-tap-pum; hence, it did not have sangryoon(the top part). However, after it was influenced by general pagodas, sangryoon was established. Toward the Tang Dynasty, sangryoon has come to emphasize the forms of boryoon(nine wheels) or dome. However, this form is eventually simplified to only retain bo-joo(the orb).

• Journal of Arbitration Studies
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• v.16 no.2
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• pp.239-264
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• 2006

Globalization of business activities and the market is making intern ational movement of capital much freer. Therefore the introduction of global standard is inevitable. Each and every country has had its own standard which restrain free exchange and cause misunderstanding and conflict between countries. A country or a company which is not capable of meeting the global standard can not be accepted in the global market. Consequently, it will eventually be left behind. It is right to say that countries and companies should accept the global standard and abide by it to survive in the competitive global market. The following preface which was introduced in the international conference co_organised by BAC, FTCTC and Tsinghua University in May, 2004 shows a timely movement for the globalization of construction business. *B A C, Beijing Arbitration Commission *FTCTC, The FIDIC-Tsinghua-CNAEC Training Center *CNAEC, China National Association of Engineering Consultants Introduction, As arbitration becomes more and more popular in the ways of alternative disputes resolution all over the world, the BAC is devoted to promoting international arbitration in China. As FIDIC contracts constitute an accepted point of reference for international construction contract, the BAC, characteristic of construction projects, is willing to facilitate the FIDIC contracts as the referred construction contracts in China. In order to carry out its purposes, the BAC, together with FTCTC is going to convene for discussion of dispute resolution and arbitration of international construction projects. FIDIC, construction contract management guide, explains arbitration as the ultimate dispute resolution method. The detail of FIDIC will be suggested in this essay.

• CELLMED
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• v.2 no.4
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• pp.35.1-35.11
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• 2012

The homeopathic remedy Chelidonium majus 200C (Chel-200) is traditionally used by homeopathic practitioners in liver ailments arising out of hepatotoxicity. The present investigation was aimed at examining whether vitamin C (L-ascorbic acid or AA), used in both traditional and orthodox medicines, can show better effects when used in combination with Chel-200, in favorably modifying the toxicological effects induced by the chronic feeding of p-dimethylaminoazobenzene (p-DAB, initiator) and phenobarbital (PB, promoter) in mice for 7 days through 120 days to induce hepatotoxicity and liver tumors. Mice were euthanized at 7, 15, 30, 60, 90, and 120 days of carcinogen feeding to assess various cytogenetical, biochemical and histological changes occurring in them. In a placebo controlled study, Chel-200 or the respective placebo (Alcohol-200C or Alc, "vehicle" of homeopathic drug), was orally administered to toxicant-fed mice. Sub-groups of the mice receiving Chel-200 were also fed either AA or an Alc placebo and their individual and conjoint effects were studied against the respective controls, to evaluate if the combination therapy of Chel-200 with AA can be of additional help in the amelioration of the toxicities generated by the toxicants. The combined feeding of Chel-200 and AA appeared to reduce the cytotoxic and genotoxic effects significantly, when compared to either only the Chel-200 or AA fed group. A similar trend was also obtained in the results of scanning and transmission electron microscopic studies of the livers. Experiments in other mammalian models are warranted to confirm if these drugs in combination could be used in palliative care of human patients with liver diseases including cancer.

• Fire Science and Engineering
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• v.34 no.4
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• pp.7-12
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• 2020

A numerical study was conducted to investigate the effects of the spray characteristics of water mist on the attenuation of thermal radiation. The attenuation process of the thermal radiation, generated from a hot surface panel, passing through the water mist was calculated via Fire Dynamics Simulator (FDS), and the effects of the flow rate, droplet mean diameter, and spray injecting angle of the water mist were analyzed. The results indicated that the increase in flowrate and decrease in droplet size led to an increase in the attenuation of thermal radiation. As the thermal radiation passed through the spray droplets, the effect of the spatial distribution of spray droplets was verified by calculating the thermal radiation attenuation at different spray injecting angles. The results indicated that the radiation attenuation increases as the spray angle increases. This implies that a wider distribution of spray droplets, irrespective of the droplet size and flowrate, increases the attenuation effect on thermal radiation.