• Proceedings of the KSMRM Conference
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• 2002.11a
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• pp.133-133
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• 2002

Purpose： The purpose of paper is to implement software to visualize brain fiber tract using a 24-bit color coding scheme and to test its feasibility. Materials and Methods： MR imaging was performed on GE 1.5 T Signa scanner. For diffusion tensor image, we used a single shot spin-echo EPI sequence with 7 non-colinear pulsed-field gradient directions： (x, y, z)：(1,1,0),(-1,1,0),(1,0,1),(-1,0,1),(0,1,1),(0,1,-1) and without diffusion gradient. B-factor was 500 sec/$\textrm{mm}^2$. Acquisition parameters are as follows： TUTE=10000ms/99ms, FOV=240mm, matrix=128${\times}$128, slice thickness/gap=6mm/0mm, total slice number=30. Subjects consisted of 10 normal young volunteers (age：21∼26 yrs, 5 men, 5 women). All DTI images were smoothed with Gaussian kernel with the FWHM of 2 pixels. Color coding schemes for visualization of directional information was as follows. HSV(Hue, Saturation, Value) color system is appropriate for assigning RGB(Red, Green, and Blue) value for every different directions because of its volumetric directional expression. Each of HSV are assigned due to (r,$\theta$,${\Phi}$) in spherical coordinate. HSV calculated by this way can be transformed into RGB color system by general HSV to RGB conversion formula. Symmetry schemes： It is natural to code the antipodal direction to be same color(antipodal symmetry). So even with no symmetry scheme, the antipodal symmetry must be included. With no symmetry scheme, we can assign every different colors for every different orientation.(H =${\Phi}$, S=2$\theta$/$\pi$, V=λw, where λw is anisotropy). But that may assign very discontinuous color even between adjacent yokels. On the other hand, Full symmetry or absolute value scheme includes symmetry for 180$^{\circ}$ rotation about xy-plane of color coordinate (rotational symmetry) and for both hemisphere (mirror symmetry). In absolute value scheme, each of RGB value can be expressed as follows. R=λw｜Vx｜, G=λw｜Vy｜, B=λw｜Vz｜, where (Vx, Vy, Vz) is eigenvector corresponding to the largest eigenvalue of diffusion tensor. With applying full symmetry or absolute value scheme, we can get more continuous color coding at the expense of coding same color for symmetric direction. For better visualization of fiber tract directions, Gamma and brightness correction had done. All of these implementations were done on the IDL 5.4 platform.

• Clinical and Experimental Reproductive Medicine
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• v.26 no.1
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• pp.103-109
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• 1999

Objective: Heat shock protein 70-2 (Hsp70-2) gene knockout mice are found to have premeiotic arrest at the primary spermatocyte stage with a complete absence of spermatids and spermatozoa. This observation led to the hypothesis that hspA2 may be disrupted in human testes with abnormal spermatogenesis. To test this hypothesis, we studied the mRNA expression of hspA2 in infertile men with azoospermia. Design: The mRNA expression were analyzed by competitive RT-PCR among testes with normal spermatogenesis, pachytene spermatocyte arrest, and sertoli-cell only syndrome. Materials and methods: Testicular biopsy was performed in men with azoospermia (n=15). Specimens were subdivided into three groups: (group 1) normal spermatogenesis (n=5), (group 2) spermatocyte arrest (n=5), (group 3) Sertoli-cell only syndrome (n=5). Total RNA was extracted by Trizol reagent. Total extracted RNA was reverse transcribed into cDNA and amplified by PCR using specific primers for hspA2 target cDNAs. A competitive cDNA fragment was constructed by deleting a defined fragment from the target cDNA sequence, and then coamplified with the target cDNA for competitive PCR. Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) gene was used as an internal control. Results: On Competitive RT-PCR analyses for hspA2 mRNA, significant amount of hspA2 expression was observed in group 1, whereas a constitutively low level of hspA2 was expressed in groups 2 and 3. Conclusion(s): The study demonstrates that the hspA2 gene expression is down-regulated in human testes with abnormal spermatogenesis, which in turn suggests that hspA2 gene may play a specific role during meiosis in human testes.

• The korean journal of orthodontics
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• v.30 no.4 s.81
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• pp.467-473
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• 2000

As a rectangular wire Is inserted into edgewise brackets the wire exerts a force system three-dimensionally. The force system may include bending force in first and second orders and a torsional force in third order Analytical and experimental studies on bending force have been Introduced, but information about torsion is still lack. The purpose of this study was to estimate the torsional moment in the force system of rectangular arch wires through theoretical and experimental studies. Wires most frequently used for third order control were selected as study materials. Cross sections of 0.016x0.022, 0.017x0.025, 0.019x0.025 inch rectangular wires in foot different materials such as stainless steel(Ormco), TMA(Ormco), NiTi(Ormco), and braided stainless steel (DentaFlex, Dentaurum) were used. The torque/twist rate of each test material was calculated using the torsion formula. Torque/twist rate, yield torsional moment, and ultimate torsional moment were measured with a torque gauge. The torsion formula assesses that the torque/twist rate (T/$\theta$) is proportional to the characteristics of material (G) and cross section (J), and is inversely proportional to the length of wire (L). Most experimental results corresponded with the formula. The relative stiffness was calculated for reference to a logical sequence of wire changes.

• Journal of Oral Medicine and Pain
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• v.36 no.3
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• pp.199-205
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• 2011

During root canal treatment, overinstrumentation with hand or mechanically driven files can perforate the mandibular canal, allowing the extrusion of endodontic sealers, dressing agents, and irrigant solutions out of the tooth and into the canal. The patient may report symptoms such as pain, hyperesthesia, hypoesthesia, anesthesia, dysesthesia and paresthesia. Such problems must be resolved as quickly as possible to avoid irreversible sequelae caused by certain neurotoxic materials that form part of endodontic sealants. Although there have been no controlled trials of treatment protocols involving endodontically related injuries to the inferior alveolar nerve, the normal therapeutic sequence for this complication is the control of pain and inflammation and, whenever possible, the surgical elimination of the cause. However, total resolution of pain and reduction in or disappearance of paraesthesia after a non-surgical management have been reported. Antiepileptic drugs such as gabapentin or pregabalin have been used for the treatment of neuropathic pain. This article describes a case of inferior alveolar nerve(IAN) damage after endodontic treatment of a mandibular right second molar and the treatment with non-surgical approach using prednisone and gabapentin medication, monitoring the patient's condition with clinical neurosensory examination and current perception threshold test(Neurometer).

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.47 no.1
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• pp.17-28
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• 2010

This paper presents a new automatic TFT-LCD image quality optimization system using DSP for the first time. Since conventional manual method depends on experiences of LCD module developers, it is highly labor-intensive and requires several correction steps providing large gamma correction error. The proposed system optimizes automatically gamma adjustment and power setting registers in mobile TFT-LCD driver IC to reduce gamma correction error, adjusting time, and flicker. It contains module-under-test (MUT, TFT-LCD module), PC installed with program, multimedia display tester for measuring luminance and flicker, and control board for interface between PC and TFT-LCD module. We have developed a new algorithm using 6-point programmable matching technique with reference gamma curve and applying automatic power setting sequence. Developed algorithm and program are generally applicable for most of the TFT-LCD modules. It is realized to calibrate gamma values of 1.8, 2.0, 2.2 and 3.0, and reduce flicker level. The control board is designed with DSP and FPGA, and it supports various interfaces such as RGB and CPU. Developed automatic image quality optimization system showed significantly reduced gamma adjusting time, reduced flicker, and much less average gamma error than conventional manual method. We believe that the proposed system is very useful to provide high-quality TFT-LCD and to improve developing process using optimized gamma-curve setting and automatic power setting.

• YAKHAK HOEJI
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• v.47 no.5
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• pp.339-344
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• 2003

Atenolol is a water soluble, ${\beta}_1$ selective adrenoceptor antagonist used in the treatment of angina and hypertension. It is primarily eliminated renally with minimal hepatic metabolism. The purpose of the present study was to evaluate the bioequivalence of Samchundang Atenolol (Samchundang Pharmaceutical Co., Korea.) to Tenolmin(Hyundai Pharmaceutical Ind. Co., Korea). The atenolol release from the two atenolol tablets in vitro was tested using KP VII Apparatus II method with various different kinds of dissolution media (pH 1.2, 4.0, 6.8 buffer solution and water). Twenty four normal male volunteers, 22.83$\pm$1.99 years in age and 65.82$\pm$7.15 kg in body weight, were divided into two groups and a randomized $2{\times}2$ cross-over study was employed. After one tablet containing 50 mg of atenolol was orally administered, blood was taken at predetermined time intervals and the concentrations of atenolol in serum were determined using HPLC method with fluorescence detector. The dissolution profiles of two atenolol tablets were very similar at all dissolution media. Besides, the pharmacokinetic parameters such as $AUC_{t}$, $C_{max}$ and $T_{max}$ were calculated and ANOVA test was utilized for the statistical analysis of the parameters using logarithmically transformed $AUC_{t}$ and $C_{max}$ and untransformed $T_{max}$. The results showed that the differences in $AUC_{t}$, $C_{max}$ and $T_{max}$ between two tablets based on the Tenolmin were 3.74％, 4.38％ and 17.77％, respectively. There were no sequence effects between two tablets in these parameters. The 90％ confidence intervals using logarithmically transformed data were within the acceptance range of log(0.8) to log(1.25) (e.g., log(0.98)∼log(1.l1) and log(0.95)∼log(1.l5) for $AUC_{t}$ and $C_{max}$ respectively), indicating that Samchundang Atenolol tablet is bioequivalent to Tenolmin tablet.

• Journal of rehabilitation welfare engineering & assistive technology
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• v.10 no.3
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• pp.237-242
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• 2016

The major advantage of slip-ring technology in Spiral CT is that it facilitates continuous rotation of the x-ray tube, so that volume data can be acquired from a patient quickly. Not only for such a fast scan, but also for the dose reduction purpose, high signal-to-noise ratio and fast data acquisition system is required. In this study, we have built a multi-channel photodetector and multi-channel data acquisition system for CT application. The detector module consisted of CdWO4 crystal and Si photodiode in 16 channels. For the performance test of the preamplifier stage, both the transimpedance and switched integrator types are optimized for the photodetector modules. Switched integrator showed better noise performance in the limited bandwidth which is suitable for the current CT application. The control sequence for data acquisition and 20 bit ADC is designed with VHDL(Very High Speed Integrated Circuit Hardware Description Language) and implemented on FPGA(Field Programmable Gate Array) chip. Our Si photodiode detector module coupled to CdWO4 crystal showed comparable signal with other commercially available photodiode for CT. Switched integrator type showed higher SNR but narrower bandwidth compared to transimpedance preamplifier. Digital hardware is designed by FPGA, so that the control signal could be redesigned without hardware alteration.

• Membrane Journal
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• v.26 no.5
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• pp.391-400
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• 2016

In this work, novel thin film composite (TFC) forward osmosis (FO) membranes are developed via interfacial polymerization on the polysulfone (PS) substrate, using TEOS as the a sol-gel reagent to form hydrophilic interlayer polymer between PS and polyamide (PA). The PS substrate was cast on a very thin polyester nonwoven to reduce membrane resistance. With the incorporation of TEOS (tetraethoxy silane) polymer in the interface between PS and PA, the formed TFC FO membrane exhibits better hydrophilicity and improved water flux, and therefore superior membrane performance. By changing the polymerization sequence of PA interfacial polymerization and TEOS sol-gel condensation, the surface properties and performance of FO membranes are changed significantly. The permeability of FO membranes were estimated using the bench-scale FO test equipment. The distribution of the polysiloxane on composite membrane and morphology are also studied with FE-SEM and EDAX. The PS_PA_TEOS membrane showed highly enhanced water flux (79.2 LMH) but reverse salt flux (RSF) value (7.10 GMH) also increased. However, the flux of PS_TEOS_PA membrane increased moderately (54.1 LMH) without increasing RSF value (1.60 GMH) compare with PS_PA membrane.

• Journal of Pharmacopuncture
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• v.3 no.1
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• pp.35-51
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• 2000

The purpose of this study is to prove the analgesic effects of apitoxin and its mechanism via jaw-opening reflex(JOR) and measuring expression of mRNA in Phospholipase and Tryptophan hydroxylase(TPH) using RT-PCR. The experiments were carried out on Sprague-Dawley rats(300-400g) and mastocytoma(P-185 HTR) for JOR and RT-PCR, respectively. Rats anesthetized with thiopental sodium (80mg/kg) were used in the Tooth Pulp stimulation induced JOR. The amplitude of a digastric electromyogram (dEMG) was recorded during the stimulation at an intensity of 1.5 times the threshold for JOR. Apitoxin used in this experiment was diluted with normal saline by 1:1000. Apitoxin was injected intravenously into the test group while normal saline to the control group. However, it was injected directly into the cell of mastocytoma. We referred to base sequence registered in Genbank in designing primers for RT-PCR. The results were as follows; (1)Compared with control group, analgesic effect started to show right after Sprague-Dawely rats were treated with apitoxin($71.50{\pm}8.08$) and lasted for 50 minutes. (2)As a result of the experiment of RT-PCR, we witnessed significant changes in the degree of expression of phospholipase or rate-limiting enzyme of biosynthesis of prostaglandins with $10{\mu}g/ml$ apitoxin.($31.74{\pm}18.98%$, P<0.05) (3)As a result of the experiment of RT-PCR, we witnessed significant changes in the degree of expression of TPH or rate-limiting enzyme in biosynthesis of serotonin with $10{\mu}g/ml$ apitoxin.($131.37{\pm}16.87%$, P<0.05). These results suggest that $10{\mu}g/ml$ apitoxin have the most analgesic effects. This study showed that apitoxin has analgesic effects and held good for 50 minutes. The injection of apitoxin has brought out changes in the degree of expression of phospholipase and TPH. These results strongly suggest that analgesic mechanism by apitoxin is closely related to prostaglandins and serotonin.

• Journal of Pharmaceutical Investigation
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• v.32 no.1
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• pp.47-54
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• 2002

Cimetropium bromide, a quaternary ammonium compound which is chemically related to scopolamine, exhibits its antispasmodic activity by competing with acetylcholine for the muscarinic receptors of the smooth muscle of gastrointestinal tract. The drug has been used for the treatment of various disorders involving spasms of the musculature of the gastrointestinal, biliary and genitourinary tracts. The purpose of the present study was to evaluate the bioequivalence of two cimetropium bromide tablets, $Algiron^{TM}$ (Boehringer Ingelheim Korea Ltd.) and $Alpit^{TM}$ (Hana Pharmaceutical Co., Ltd.), according to the prior and revised guidelines of Korea Food and Drug Administration (KFDA). The cimetropium bromide release from the two cimetropium bromide tablets in vitro was tested using KP VII Apparatus II method with various different kinds of dissolution media (pH 1.2, 4.0, 6.8 buffer solution and water). Twenty normal male volunteers, $25.25{\pm}2.10$ years in age and $65.76{\pm}6.39$ kg in body weight, were divided into two groups and a randomized $2{\times}2$ cross-over study was employed. After three tablets containing 50 mg of cimetropium bromide per tablet were orally administered, blood was taken at predetermined time intervals and the concentrations of cimetropium bromide in serum were determined using HPLC method with UV detector. The dissolution profiles of two cimetropium bromide tablets were very similar at all dissolution media. Besides, the pharmacokinetic parameters such as $AUC_t,\;C_{max}\;and\;T_{max}$ were calculated and ANOVA test was utilized for the statistical analysis of the parameters using non-transformed and logarithmically transformed $AUC_t\;and\;C_{max}$. The results showed that the differences in $AUC_t,\;C_{max}\;and\;T_{max}$ between two tablets based on the $Algiron^{TM}$ were 2.19%, -5.97% and 3.49%, respectively. Minimum detectable differences $({\Delta})\;at \;{\alpha}=0.05\;and\;1-{\beta}=0.8$ were less than 20% (e.g., 13.71 %, 19.05% and 15.11% for $AUC_t,\;C_{max}\;and\;T_{max}$, respectively). The powers $(1-{\beta})\;at\;{\alpha}=0.05,\;{\Delta}=0.2\;for\;AUC_t$, $C_{max}\;and\;T_{max}$ were 97.79%, 83.22% and 95.60%, respectively. The 90% confidence intervals were within ${\pm}20%$ (e.g., $-5.84{\sim}10.21,\;-17.11{\sim}5.18\;and\;-5.35{\sim}12.33\;for\;AUC_t,\;C_{max}\;and\;T_{max}$, respectively). There were no sequence effect between two tablets in logarithmically transformed $AUC_t\;and\;C_{max}$. The 90% confidence intervals using logarithmically transformed data were within the acceptance range of log(0.8) to log(1.25) (e.g., $0.94{\sim}1.10\;and\;0.85{\sim}1.05\;for\;AUC_t\;and\;C_{max}$, respectively). Two parameters met the criteria of prior and revised KFDA guideline for bioequivalence, indicating that $Alpit^{TM}$ tablet is bioequivalent to $Algiron^{TM}$ tablet.