• Korean Journal of Environmental Agriculture
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• v.6 no.1
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• pp.31-37
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• 1987

A study has been conducted to investigate the behavior of carbofuran in a miniature paddy agrosystem simulated for paddy field. Carbofuran applied onto the paddy water was rapidly absorbed and translocated into rice plants. Carbofuran concentration in rice plant reached its maximum level between 1 to 3 days after treatment and gradually decreased thereafter. Half life of carbofuran concentration in paddy water was 4 days in both application rates of 0.12 and 0.24Kg a.i./10a. Carbofuran residue in paddy soil was gradually dissipated with the half life of 8 and 12 days in 0.12 and 0.24㎏ a.i./l0a respectively. Range of carbofuran residue in brown rice and rice straw harvested from the paddy agrosystem was 0.01∼0.02 ppm and 0.37∼0.57 ppm irrespective of the two application rates respectively.

• Journal of Embryo Transfer
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• v.32 no.3
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• pp.249-255
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• 2017

In this experiment, we determined the effect of curcumin supplementation in freezing buffer for miniature pig sperm cryopreservation. Each ejaculate was diluted with modified Modena B extender and mixed with lactose-egg yolk (LEY extender, 80% v/v lactose solution [310 mM], 20% v/v egg yolk, and $100{\mu}g/mL$ kanamycin sulfate) and LEY-glycerol Orvus ES Paste (LEYGO, 89.5% v/v LEY, 5% v/v glycerol, 1.5% v/v Orvus ES Paste), 100 mM trehalose supplemented with 0, 10, 50, 100, and $500{\mu}M$ of curcumin from turmeric, respectively. Following equilibration, the 0.5 mL French straws were frozen and plunged into $LN_2$ tank for 7 days at least. Sperm parameter and oxidative byproducts were determined by the computer assisted sperm motility analysis (CASA) and fluorescence-activated cell sorting (FACS) as compared with each groups. Supplementation of curcumin had no effect on sperm motility, progressive motility and curvilinear velocity. However, average-path velocity and straight-line velocity were significantly higher in $10{\mu}M$ curcumin group ($100.9{\pm}8.8{\mu}m/s$, $61.7{\pm}2.9{\mu}m/s$, respectively) than control group ($77.8{\pm}3.9{\mu}m/s$, $46.4{\pm}3.0{\mu}m/s$, respectively) (p < 0.05). In addition, the level of the O2 radical and H2O2 were comparatively decreased in curcumin groups by evaluation of ethidium and DCF fluorescence. According to the results, curcumin can improve sperm kinetic variables and alleviate ROS induced cryoinjury to pig sperm.

• Journal of Chest Surgery
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• v.45 no.5
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• pp.287-294
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• 2012

Background: Biologic valved grafts are important in cardiac surgery, and although several types of graft are currently available, most commercial xenografts tend to cause early disfiguration due to intimal proliferation and calcification. We studied the graft failure patterns on non-fixed and glutaraldehyde-fixed pulmonary xenograft in vivo animal experiment. Materials and Methods: Pulmonary valved conduits were obtained from the right ventricular outflow tract of eleven miniature pigs. The grafts were subjected to 2 different preservation methods; with or without glutaraldehyde fixation: glutaraldehyde fixation (n=7) and non-glutaraldehyde fixation (n=4). The processed explanted pulmonary valved grafts of miniature pig were then transplanted into eleven goats. Calcium quantization was achieved in all of the explanted xenograft, hemodynamic, histopathologic and radiologic evaluations were performed in the graft which the transplantation period was over 300 days (n=7). Results: Grafts treated with glutaraldehyde fixation had more calcification and conduit obstruction in mid-term period. Calcium deposition also appeared much higher in the glutaraldehyde treated graft compared to the non-glutaraldehyde treated graft (p<0.05). Conclusion: The present study suggests that xenografts prepared using glutaraldehyde fixation alone appeared to have severe calcification compared to the findings of non-glutaraldehyde treated xenografts and to be managed with proper anticalcification treatment and novel preservation methods. This experiment gives the useful basic chemical, histologic data of xenograft failure model with calcification for further animal study.

• Korean Journal of Veterinary Research
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• v.44 no.4
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• pp.621-624
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• 2004

A 13-year-old female Miniature Pincher was euthanized after suffering from respiratory insufficiency and seizure. At necropsy, firm tan masses approsimately 4 to 5 cm in diameter were noted at the right caudal love and left cranial lobe of the lung. On cross sections of the cerebellum and the verebrum, several compressive firm round masses, 0.5 to 1 cm in diameter, were noted. similar looking nodules were also present in the mediastinal lymph nodes. Histopathologically, the neoplastic masses consisted of cuboidal shape epithelial cells that form glandular structure. The neoplastic cells have hyperchromatic nuclei with prominent nucleoli and moderate amount of cytoplasm. The degree of mitosis was high (4-6/400X). Multiple areas of necrosis, hemorrhage, and tumor emboli were also noted. Metastasis to the mediastinal lymph nodes, pancreas, and brain was confirmed. Based on the gross and histopathologic examinations, a diagnosis of primary metastatic pulmonary adenocarcinoma was made. Clinicaly recognized neurological signs were therefore due to brain metastasis.

• The Korean Journal of Physiology and Pharmacology
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• v.27 no.1
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• pp.39-48
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• 2023

Spinal nerve injury causes mechanical allodynia and structural imbalance of neurotransmission, which were typically associated with calcium overload. Storeoperated calcium entry (SOCE) is considered crucial elements-mediating intracellular calcium homeostasis, ion channel activity, and synaptic plasticity. However, the underlying mechanism of SOCE in mediating neuronal transmitter release and synaptic transmission remains ambiguous in neuropathic pain. Neuropathic rats were operated by spinal nerve ligations. Neurotransmissions were assessed by whole-cell recording in substantia gelatinosa. Immunofluorescence staining of STIM1 with neuronal and glial biomarkers in the spinal dorsal horn. The endoplasmic reticulum stress level was estimated from qRT-PCR. Intrathecal injection of SOCE antagonist SKF96365 dose-dependently alleviated mechanical allodynia in ipsilateral hind paws of neuropathic rats with ED₅₀ of 18 ㎍. Immunofluorescence staining demonstrated that STIM1 was specifically and significantly expressed in neurons but not astrocytes and microglia in the spinal dorsal horn. Bath application of SKF96365 inhibited enhanced miniature excitatory postsynaptic currents in a dosage-dependent manner without affecting miniature inhibitory postsynaptic currents. Mal-adaption of SOCE was commonly related to endoplasmic reticulum (ER) stress in the central nervous system. SKF96365 markedly suppressed ER stress levels by alleviating mRNA expression of C/ EBP homologous protein and heat shock protein 70 in neuropathic rats. Our findings suggested that nerve injury might promote SOCE-mediated calcium levels, resulting in long-term imbalance of spinal synaptic transmission and behavioral sensitization, SKF96365 produces antinociception by alleviating glutamatergic transmission and ER stress. This work demonstrated the involvement of SOCE in neuropathic pain, implying that SOCE might be a potential target for pain management.

• Proceedings of the Korean Geotechical Society Conference
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• 2000.02a
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• pp.42-58
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• 2000

본 연구의 목적은 연약지반의 압밀계수 측정에 있어 Piezocone 관입시험을 이용할 때 관입시험자체의 정확성과 시험결과들에 미치는 여러 가지 지반공학적 영향요소들을 고려하려는데 있다. 본 연구의 연구실험방법으로는, Piezocone 관입을 위한 연약모형지반 조성을 위하여 초대형 Slurry Consolidometer에 Free Stress 상태의 Slurry를 45일간 압밀시킨 후 Automatic Computer Control Calibration Chamber (LSU/CALCHAS; Louisiana State University Calibration Chamber System)에 옮긴후 다시한번 압밀시키는 Two-Stage Consolidation Method를 사용하였다 동시에 연약모형지반내에 8개의 Piezometer를 설치하여 Piezocone 관입시 유발되는 지반 내에서의 과잉간극수압의 변환을 측정하였다. 총 25개의 Piezocone 시험중 4개는 Standard 10$\textrm{cm}^2$ Piezocone이고, 나머지 21개는 Miniature Piezocone이 사용되었다. 모형지반은 여러 가지 Boundary Condition들과 Stress Condition 그리고 Stress History등을 고려하여 조성되었다. 또한 Dissipation Test직후의 압밀특성을 확인하기 위하여 0.01초당 한 개이상의 실측점을 측정할 수 있는 Digital-Oscilloscope를 이용하였다. 특히 Dissipation Test, 즉시 Piezocone의 Filter Element에 잡히지 않는 과잉간극수압의 Initial Drop 존재에 관한 기존의 추측을 실제 실험치로 확인할 수 있었다.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2002.10b
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• pp.303-304
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• 2002

This paper presents theoretical analysis of the NRRO(the non-repeatable run-out) for a ball bearing with geometric imperfection. This imperfection contains ball size error, ball waviness, outer race waviness and inner race waviness. The 3D dynamic analysis of a ball bearing using the Newton-Raphson method is performed to calculate the displacement of shaft center. The radial and axial NRRO are simulated, and preload and clearance effects are investigated. Preload and clearance have significant effects on radial and axial NRRO of for miniature ball bearings.

• Proceedings of the Acoustical Society of Korea Conference
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• spring
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• pp.381-384
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• 2000

초음파 음장의 상대적인 변화를 측정하는데 사용하기 위한 극소형 수중 청음기를 제작하고 그 특성을 평가하였다. 압전체로서는 PVDF(Poly Vinylidene Di Fluoride) 고분자막을 사용하였으며, 수신 특성을 향상시키기 위해 임피던스 변환회로를 부가하였다. 본 논문에서는 설계된 수중 청음기의 초음파 수신특성을 Mason 등가회로에 의해 이론적으로 평가한 결과 및 극소형 수중 청음기의 제작 방법, 그리고 제작한 청음기의 초음파 수신 특성에 대하여 보고한다.

• Design & Manufacturing
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• v.2 no.6
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• pp.38-42
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• 2008

Recently, the demands of digital camera and miniature camera module for mobile-phone is increased significantly. Lenses which is the core component of optical products are made by the injection molding(plastic lens) or GMP(glass lens). Plastic lens is not enough to improve the resolution and performance of optic parts. Therefore, the requirement of glass lens is increased because it is possible to ensure the high performance and resolution. In this paper, the thermal stress analysis of 3 cavity GMP mold for molding glass lens was performed for estimating the thermal stress and amount of deformation. Finally, the modification plan based on the analysis results was deducted.

• Journal of the Korean Society for Precision Engineering
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• v.17 no.4
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• pp.114-120
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• 2000

Burr is an unavoidable and undesirable by-product of most metal cutting or shearing operations. This burr must be removed to improve the fit of machined parts and safety of workers, to improve the effectiveness of finishing operations. Despite the full or partial automation of FMC or FMS, deburring operations to obtain workpiece with fine surface quality are difficult to be automated since the occurrence and condition of burr are not constant. This study focused on developing a software for deburring automation, which includes automatic recognition of parts, generation of deburring tool path and NC code, by analyzing the IGES format file which contains information of part geometry. The successful performance of developed software was demonstrated by computer simulation and deburring experiment using miniature end brush. And, this research can provide a basis for further advanced studies for automated deburring applications.