• Animal cells and systems
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• v.9 no.3
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• pp.107-111
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• 2005

C. elegans DLK-1 has been reported to play an important role in synaptogenesis by shaping the structure of presynaptic terminal. In this study, we investigated the expression pattern and regulation of the dlk-1 gene in C. elegans. To determine the expression pattern, we made a dlk-1::gfp fusion construct, named pPDdg1, which consisted of -2.2 kb 5' upstream region, the first exon, the first intron, and a part of the second exon of the dlk-1 gene. By microinjecting this construct into the worm, we observed that the DLK-1::GFP was expressed mainly in neurons. We next examined the regulatory elements of gene expression by deletion analysis of pPDdg1. Removal of a large portion of the 5' upstream region (${\Delta}-361$ to -2246) of the gene had little effect on the expression pattern, whereas deletion of the first intron led to elimination of the DLK-1::GFP expression in most of the neurons. Our results suggest that the first intron of the C. elegans dlk-1 gene contains the regulatory element critical for gene expression.

• Journal of the Microelectronics and Packaging Society
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• v.19 no.2
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• pp.29-33
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• 2012

The demand for 3D wafer level integration has been increasing significantly. Although many technical challenges of wafer stacking are still remaining, wafer stacking is a key technology for 3D integration due to a high volume manufacturing, smaller package size, low cost, and no need for known good die. Among several new process techniques Cu-to-Cu wafer bonding is the key process to be optimized for the high density and high performance IC manufacturing. In this study two main challenges for Cu-to-Cu wafer bonding were evaluated: misalignment and bond quality of bonded wafers. It is demonstrated that the misalignment in a bonded wafer was mainly due to a physical movement of spacer removal step and the bond quality was significantly dependent on Cu bump dishing and oxide erosion by Cu CMP.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.02a
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• pp.414-414
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• 2010

KSTAR vacuum vessel has been boronized by carborane ($C_2B_{10}H_{12}$) to reduce various kinds of impurities including carbon and oxygen from the wall, since carborane is solid, non-toxic, non-explosive and is easily evaporated, while diborane ($B_2D_6$) is toxic and explosive. To find the best wall condition for the removal of contaminants before application to KSTAR, various amounts (0.3g, 0.5g, 1g) of carborane are tested in a test chamber, where filament discharge was generated in the mixture of helium and carborane with the same KSTAR target pressure (~ 5 mTorr) from base pressure (${\sim}10^-7\;Torr$). Discharge is performed by a pulse sequence mode with 3 second power on and 5 second power off. Deposited films of a-C/B:H are characterized by ellipsometery, AES and XPS, and are compared with those of KSTAR.

• Journal of Environmental Science International
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• v.30 no.9
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• pp.719-726
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• 2021

In this study, zeolitic materials were synthesized from Jeju Volcanic Rocks (JVR) using a fusion/hydrothermal method at NaOH/JVR ratios of 0.6 and 1.2. The crystallinities of the zeolitic materials at NaOH/JVR ratios of 0.6 and 1.2 were 25.5% and 59.0%, respectively. It was confirmed through the SEM image that the zeolitic materials covered the zeolite particle with a cube-shaped crystals. The Co ions adsorption by the zeolitic materials were to reach the adsorption equilibrium at 120 min. It could be better simulated in the pseudo-second order adsorption kinetic equation than in the pseudo-first order adsorption kinetic equation. The adsorption capacities (q_m) of Co ions could be to estimate Langmuir isotherm better than Freundlich isotherm. The maximum adsorption capacities (q_m) at NaOH/JVR ratios of 0.6 and 1.2 were 55.3 mg/g and 68.7 mg/g, respectively. It was found that there was a high correlation between the crystallinity of zeolitic materials and the adsorption capacity of Co ions adsorption.

• Journal of Environmental Science International
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• v.32 no.5
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• pp.343-353
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• 2023

A zeolite material (ZCH) was synthesized from coal fly ash in an HD thermal power plant using a fusion/hydrothermal method. ZCH with high crystallinity could be synthesized at the NaOH/CFA ratio of 0.9. Ion-exchanged ZCH adsorbents for ammonia removal were prepared by ion-exchanging various cation (Cu²⁺, Co²⁺, Fe³⁺, and Mn²⁺) on the ZCH. They were used to evaluate the ammonia adsorption breakthrough curves and adsorption capacities. The ammonia adsorption capacities of the ZCH and ion-exchanged ZCHs were high in the order of Mn-ZCH > Cu-ZCH ≅ Co-ZCH > Fe-ZCH > ZCH according to NH₃-TPD measurements. Mn-ZCH ion-exchanged with Mn has more Brønsted acid sites than other adsorbents. The ion-exchanged Cu²⁺, Co²⁺, Fe³⁺, or Mn²⁺ ions uniformly distributed on the surface or in the pores of the ZCH, and the number of acidic sites increased on the alumina sites to form the crystal structure of zeolite material. Therefore, when the ion-exchanged ZCH was used, the adsorption capacity for ammonia gas increased.

• Polymer(Korea)
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• v.30 no.3
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• pp.259-265
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• 2006

Small intestinal submucosa (SIS) consists of some growth factors which can stimulate cell activity, and PVA has been widely utilized in the area of wound dressing as hydrogel which is easy to be removed from wounds. In this study, native SIS sheets were coated with PVA by immersing them into 2, 4, and 10 wt% of PVA solution and then lyophilized on two type of molds to endow the prepared wound dressing with easy removal property from wounds. The mechanical properties were examined through tensile test. Moreover, enzymatic degradation, water uptake, and in vitro test were carried out to characterize the prepared SIS sheets. The tensile strength of the SIS sheets coated with PVA (PVA-SIS) were decreased, whereas the elongation were increased. Degradation ratio of the PVA-SIS sheets was decreased compare to native SIS. Water uptake ability was improved at 2 and 4 wt% of PVA. The degree of fibroblast attachment was lower than the native SIS sheets. In conclusion, this study suggests that the PVA coated SIS sheets have a potential for the applications of wound dressing and biodegradable injectable materials.

• Tuberculosis and Respiratory Diseases
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• v.55 no.4
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• pp.402-407
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• 2003

Mesoblastic nephroma is a neoplasm of the kidney which is characterized by interlacing bundles of spindle mesenchymal cells. It is usually diagnosed during the first six months of life and is mostly benign. Incidence in adults is exceedingly rare. In most cases, only total excision is required without postoperative adjuvant therapy, and the rare cases of local recurrence have usually been related to incomplete removal. However, mesoblastic nephroma may behave aggressively, in contrast to a congenital mesoblastic nephroma. Several cases of metastatic mesoblastic nephroma have been previously described. We report herein a case of a 42-year-old woman with mesoblastic nephroma which recurred as a large metastatic lung mass seven years after the nephrectomy. The patient presented with chest wall discomfort for four days. Seven years previously, total nephrectomy had been performed because of a right renal tumor which had been diagnosed as a mesoblastic nephroma. There had been no evidence of recurrence for five years, after which she discontinued follow-up. On readmission two years later, chest X-ray and CT scan revealed a large lung mass in the left upper lobe. It was completely excised and the pathologic examination was identical with that of the original renal tumor. Synovial sarcoma was excluded because the fusion transcripts of the SYT-SSX fusion gene associated with the t(X;18) translocation were negative. The final diagnosis was a lung metastasis of mesoblastic nephroma and the patient remained free of disease for 7 months postoperatively.

• Journal of Korean Foot and Ankle Society
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• v.8 no.1
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• pp.46-51
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• 2004

Purpose: Problematic late sequelae are common following a calcaneal fracture regardless of the initial treatment. We retrospectively evaluated the painful conditions and reviewed the results of the operative treatment in patients with previously treated calcaneal fractures. Materials and Methods: Between October 1996 and September 2001, forty-three patients who underwent subsequent surgical treatment for late sequelae of calcaneal fracture were reviewed. The initial treatment consisted of only immobilization in a cast in 7 patients, closed reduction with pin fixation (Essex-Lopresti technique) in 22 and open reduction and internal fixation in 14. Painful conditions in the hind foot included subtalar arthritis in 31 patients, calcaneofibular impingement in 13, peroneal tendinitis in 6, displaced posterior bony fragment in 3, sural neuritis in 2, subtalar and midtarsal arthritis in 1 and displaced plantar bony fragment in 1. The surgical procedures for the late complications were performed at a mean of 19 months (range, 6 to 35 months) after the injury and consisted of lateral wall ostectomy and in situ subtalar fusion in 28 patients, only lateral wall ostectomy in 5 patients, lateral wall ostectomy and subtalar distraction arthrodesis in 3, removal of displaced posterior bony fragment in 3, sural nerve transposition in the peroneus brevis in 2, triple arthrodesis in 1 and removal of displaced plantar bony fragment in 1. Mean postoperative follow up period was 57 months (range, 33 to 82 months). The results of treatment were evaluated on the basis of pain, improvement in the ability to perform activities of daily living, to return to work or to a pre-injury level of activity. Results: Pain was partially relieved in 38 patients (88%), but not relieved in 5. Function improved in 34 patients (79%), and 32 (74%) returned to work or to a pre-injury level of activity. There was a trend that the longer the interval between the injury and the operation, the longer the subsequent interval until the patient returned to full activities or work. Conclusion: Meticulous physical examination and intensive prompt treatment for remaining pain after initial treatment of calcaneal fractures are recommended for patient's satisfaction and returning to work.

• Korean Journal of Microbiology
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• v.48 no.3
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• pp.187-191
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• 2012

Two-component system (TCS)-based bacterial zinc and copper biosensors, in which green fluorescent protein (GFP) is expressed under the control of zraP and cusC promoter in ZraS/R and CusS/R TCS, were evaluated in artificial wastewater. Bacterial biosensors developed in this study efficiently expressed GFP by the recognition of $Zn^{2+}$ and $Cu^{2+}$ in artificial wastewater. Secondly, TCS-based zinc and copper removing bacteria with the peptide displayed on cell surface were examined in artificial wastewater. Zinc and copper removing bacteria expressed the peptide as a fusion protein such as OmpC-ZBP (zinc binding peptide) and OmpC-CBP (copper binding peptide) on the cell surface when sensing exogenous $Zn^{2+}$ and $Cu^{2+}$ through ZraS/R and CusS/R TCS. The recombinant cell expressing metal-adsorbing peptide could efficiently remove copper and zinc (15 and 18 mg/g dry cell weight, respectively) in artificial wastewater. Therefore, it was demonstrated that the TCS-based recombinant cell for the recognition or removal of heavy metal functions well in artificial wastewater environment.

• Applied Chemistry for Engineering
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• v.33 no.1
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• pp.38-43
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• 2022

The effect of introducing oxygen functional groups by oxygen plasma treatment of activated carbon on adsorption properties of cesium ions was investigated. During the oxygen plasma treatment, the frequency, power, and oxygen gas flow rates were fixed at 100 kHz, 80 W, and 60 sccm, respectively, while the reaction time was varied. Under the experimental conditions, the amount of cesium ion adsorption increased as the content of oxygen groups on C-O-C and O=C-O bonds increased when the reaction time with oxygen gas was 10 minutes. However, when the reaction time increased to 15 minutes, the oxygen functional group content decreased resulting in the decrease of the adsorbed cesium ion amount. On the other hand, unlike the oxygen content of the surface-treated activated carbon, the specific surface area and pore properties were hardly affected by the oxygen plasma reaction time. As a result, the oxygen plasma-treated activated carbon improved the cesium ion removal rate by up to 97.3% compared to that of the untreated activated carbon. This is considered to be due to the content of oxygen groups on C-O-C and O=C-O bonds introduced on the surface of the activated carbon through oxygen plasma treatment.