• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.207-207
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• 2011

Amorphous transparent oxide semiconductors (a-TOS) have been widely studied for many optoelectronic devices such as AM-OLED (active-matrix organic light emitting diodes). Recently, Nomura et al. demonstrated high performance amorphous IGZO (In-Ga-Zn-O) TFTs.1 Despite the amorphous structure, due to the conduction band minimum (CBM) that made of spherically extended s-orbitals of the constituent metals, an a-IGZO TFT shows high mobility.2,3 But IGZO films contain high cost rare metals. Therefore, we need to investigate the alternatives. Because Aluminum has a high bond enthalpy with oxygen atom and Alumina has a high lattice energy, we try to replace Gallium with Aluminum that is high reserve low cost material. In this study, we focused on the electrical properties of IZO:Al thin films as a channel layer of TFTs. IZO:Al were deposited on unheated non-alkali glass substrates (5 cm ${\times}$ 5 cm) by magnetron co-sputtering system with two cathodes equipped with IZO target and Al target, respectively. The sintered ceramic IZO disc (3 inch ${\phi}$, 5 mm t) and metal Al target (3 inch ${\phi}$, 5 mm t) are used for deposition. The O2 gas was used as the reactive gas to control carrier concentration and mobility. Deposition was carried out under various sputtering conditions to investigate the effect of sputtering process on the characteristics of IZO:Al thin films. Correlation between sputtering factors and electronic properties of the film will be discussed in detail.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.9 no.2
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• pp.5-11
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• 2003

Thoracic outlet syndrome is actually a collection of syndromes brought about by abnormal compression of the neurovascular bundle by bony, ligamentous or muscular obstacles between the cervical spine and the lower border of the axilla. First of all a syndrome is defined as a group of signs and symptoms that collectively characterize or indicate a particular disease or abnormal condition. The neurovascular bundle which can suffer compression consists of the brachial plexus plus the C8 and T1 nerve roots and the subclavian artery and vein. The brachial plexus is the network of motor and sensory nerves which innervate the arm, the hand, and the region of the shoulder girdle. The vascular component of the bundle, the subclavian artery and vein transport blood to and from the arm. the hand. the shoulder girdle and the regions of the neck and head. The bony, ligamentous, and muscular obstacles all define the cervicoaxillary canal or the thoracic outlet and its course from the base of the neck to the axilla or arm pit. Look at the scheme of this region and it all becomes more easily understood. Compression occurs when the size and shape of the thoracic outlet is altered. The outlet can be altered by exercise, trauma, pregnancy, a congenital anomaly, an exostosis, postural weakness or changes. Thoracic outlet syndrome has been described as occurring in a diverse population. It is most often the result of poor or strenuous posture but can also result from trauma or constant muscle tension in the shoulder girdle. The first step to beginning any treatment begins with a trip to the doctor. Make a list of all of the symptoms which seem to be present even if the sensations are vague. Make a note of what activities and positions produce or alleviate the symptoms and the time of day when symptoms are worst. Also, note when the symptoms first appeared. This list is important and should also include any questions one may have.

• Korean Journal of Materials Research
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• v.20 no.10
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• pp.535-542
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• 2010

In this study, we used coal-based activated carbons and charcoal as startingmaterials, phenolic resin (PR) as a binder, and TOS as a titanium source to prepare $TiO_2$ combining spherical shaped activated carbon photocatalysts. The textural properties of the activated carbon photocatalysts (SACP) were characterized by specific surface area (BET), energy dispersive X-ray spectroscopy (XRD), scanning electron microscopy (SEM), iodine adsorption, strength intensity, and pressure drop. The photocatalytic activities of the SACPs were characterized by degradation of the organic dyes Methylene Blue (MB), Methylene Orange (MO), and Rhodamine B (Rh. B) and a chemical oxygen demand (COD) experiment. The surface properties are shown by SEM. The XRD patterns of the composites showed that the SACP composite contained a typical single, clear anatase phase. The EDX spectro for the elemental indentification showed the presence of C and O with Ti peaks. According to the results, the spherical activated carbon photocatalysts sample of AOP prepared with activated carbon formed the best spherical shape, a high BET surface area, iodine adsorption capability and strength value, and the lowest pressure drop, and the photocatalytic activity was better than samples prepared with charcoal. We compared the degradation effects among three kinds of dyes. MB solution degraded with the SACP is better than any other dye solutions.

• Korean Journal of Materials Research
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• v.20 no.8
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• pp.429-433
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• 2010

In this study, activated carbon (AC) as a carbon source was modified with different concentrations of cobalt chloride ($CoCl_2$) to prepare a Co-AC composite, and it was used for the preparation of Co-AC/$TiO_2$ composites with titanium oxysulfate (TOS) as the titanium precursor. The physicochemical properties of the prepared Co-AC/$TiO_2$ composites were characterized by $N_2$ adsorption at 77 K, X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive X-ray (EDX) analysis. The photocatalytic treatments of organic dyes were examined under an irradiation of visible light with different irradiation times. $N_2$ adsorption data showed that the composites had decreased surface area compared with the pristine AC, which was $389\;m^2/g$. From the XRD results, the Co-AC/$TiO_2$ composites contained a mixturephase structuresof anatase and rutile, but a cobalt oxide phase was not detected in the XRD pattern. The EDX results of the Co-AC/$TiO_2$ composites confirmed the presence of various elements, namely, C, O, Ti, and Co. Subsequently, the decomposition of methylene orange (MO, $C_{14}H_{14}N_3NaO_3S$) and rhodamine B (Rh.B, $C_{28}H_{31}ClN_2O_3$) in an aqueous solution, respectively, showed the combined effects of an adsorption effect by AC and the photo degradation effect by $TiO_2$. Especially, the Co particles in the Co-AC/$TiO_2$ composites could enhance the photo degradation behaviors of $TiO_2$ under visible light.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.26 no.8
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• pp.602-607
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• 2013

Concern for the TOS (Transparent Oxide Semiconductor) is increasing with the recent increase in interest for flexible device. Especially MgZnO has attracted a lot of attention. $Mg_xZn_{1-x}O$, which ZnO-based wideband-gap alloys is tuneable the band-gap ranges from 3.36 eV to 7.8 eV. In particular, the flexible substrate, the crystal structure of the amorphous as well as the surface morphology is not good. So research of MgZnO thin films growth on flexible substrate is essential. Therefore, in this study, we studied on the effects of the oxygen partial pressure on the structural and crystalline of $Mg_{0.1}Zn_{0.9}O$ thin films. MgZnO thin films were deposited on PES substrate by using pulsed laser deposition. We used XRD and AFM in order to observe the structural characteristics of MgZnO thin films. UV-visible spectrophotometer was used to get the band gap and transmittance. Crystallization was done at a low oxygen partial pressure. The crystallinity of MgZnO thin films with increasing temperature was improved, Grain size and RMS of the films were increased. MgZnO thin films showed high transmittance over 80% in the visible region.

• Animal cells and systems
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• v.4 no.1
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• pp.71-76
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• 2000

The aim of this study was to investigate expression patterns of the prolactin (PRL) and c-fos genes by 17$\beta$-estradiol (17$\beta$-E) and stress in the mouse pituitary. In the pituitary, the levels of PRL mRNA were found high with some fluctuation at 30, 50, and 90 min whereas the levels of PRL mRNA were low at 120 min when ovariectomized female mice were injected with 17$\beta$-E or vehicle. PRL mRNA levels began to increase again at 4 h and remained high up to 24 h only in the 17$\beta$-E- treated mice. The overall changes in c-fos mRNA by 17$\beta$-E were very similar to those in PRL mRNA in the pituitary. Subsequent study revealed that these high initial levels of PRL and c-fos mRNAs were caused by stress during Injection, not by 17$\beta$-E, since vehicle injection alone into the ovariectomized mice could increase the levels of PRL and c-fos mRNAs. The stress-induced elevations of PRL and c-fos mRNAs were inhibited by bromocriptin, a dopamine agonist, suggesting that the dopaminergic system is involved in the action route of injection stress. In addition, the induced levels of c-fos mRNA by 17$\beta$-E and stress in the pituitary were very low compared with those in the uterus. The time course changes in c-fos mRNA level were different between the pituitary and uterus. Taken together, these data indicate that PRL and c-tos gene expression in the pituitary are regulated by 17$\beta$-E and stress in a parallel manner, supporting the notion that c-Fos plays a role in regulation of PRL gene expression.

• Molecules and Cells
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• v.21 no.1
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• pp.147-152
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• 2006

Most plant organs develop from meristems. Rice FON1, which is an ortholog of Clv1, regulates stem cell proliferation and organ initiation. The point mutations, fon1-1 and fon1-2, disrupt meristem balance, resulting in alteration of floral organ numbers and the architecture of primary rachis branches. In this study, we identified two knockout alleles, fon1-3 and fon1-4, generated by T-DNA and Tos17 insertion, respectively. Unlike the previously isolated point mutants, the null mutants have alterations not only of the reproductive organs but also of vegetative tissues, producing fewer tillers and secondary rachis branches. The mutant plants are semi-dwarfs due to delayed leaf emergence, and leaf senescence is delayed. SEM analysis showed that the shoot apical meristems of fon1-3 mutants are enlarged. These results indicate that FON1 controls vegetative as well as reproductive development by regulating meristem size.

• Plant Breeding and Biotechnology
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• v.6 no.4
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• pp.313-320
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• 2018

Rice is the staple food of more than 50% of the world population. Cultivated rice has the AA genome (diploid, 2n = 24) and small genome size of only 430 megabase (haploid genome). As the sequencing of rice genome was completed by the International Rice Genome Sequencing Project (IRGSP), many researchers in the world have been working to explore the gene function on rice genome. Insertional mutagenesis has been a powerful strategy for assessing gene function. In maize, well characterized transposable elements have traditionally been used to clone genes for which only phenotypic information is available. In rice endogenous mobile elements such as MITE and Tos have been used to generate gene-tagged populations. To date T-DNA and maize transposable element systems have been utilized as main insertional mutagens in rice. The Ac/Ds system offers the advantage of generating new mutants by secondary transposition from a single tagged gene. To enhance the efficiency of gene detection, advanced gene-tagging systems (i.e. activation, gene or enhancer trap) have been employed for functional genomic studies in rice. Internationally, there have been many projects to develop large scales of insertional mutagenized populations and databases of insertion sites has been established. Ultimate goals of these projects are to supply genetic materials and informations essential for functional analysis of rice genes and for breeding using agronomically important genes. In this report, we summarize the current status of Ac/Ds-mediated gene tagging systems that has been conducted by collaborative works in Korea.

• Safety and Health at Work
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• v.14 no.1
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• pp.118-123
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• 2023

Background: Chronic exposure to silica is related with the provocation of an inflammatory response and oxidative stress mechanism. Vitamin D has multiple benefits in biological activities particularly respiratory system disease. Method: In this research, 20 male Wistar rats were randomly allocated into four groups (5 rats /group) as follow: Group1 received saline as (negative control) group. The group 2 received a single IT instillation of silica (positive control) group; the group 3 was co-administrated with single IT silica and Vitamin D (20 mg/kg/day) daily for a period of 90 days. The rats of group 4 received Vitamin D daily for a period of 90 days. Results: Silica significantly increased serum and lung total Oxidant Status (TOS). Meanwhile, silica reduced serum and lung total antioxidant capacity (TAC), GSH and tumor necrosis factor-α (TNF-a). Vitamin D treatment meaningfully reversed oxidative stress, antioxidants status and inflammatory response. Also, Vitamin D improved histopathological changes caused by silica. Conclusion: These findings indicate that Vitamin D exerts protective effects against silica-induced lung injury. It seems that Vitamin D has potential use as a therapeutic object for silica induced lung injure.

• Journal of Chest Surgery
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• v.38 no.12 s.257
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• pp.844-848
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• 2005

Background: Thoracic outlet syndrome(TOS) is caused by the compression of neurovascular structures that supply to the upper extremities. Only a few reports have been published in Korea, and this study attempts to investigate the clinical aspects and results of the patients who underwent surgical treatment. Material and Method: This study consist of 16 patients who underwent operations for thoracic outlet syndrome from May, 2002 to October, 2004. The surgical indications were confined to patients with: 1) symptom too severe to perform ordinary daily life because of pain, paresthesia, edema of upper extremities, 2) no improvement after proper physical therapy, 3) definite finding of compression confined by radiologic examinations (MRI, angiography, etc), and 4) no other diseases such as cervical intervertebral herniation, myositis, neurologic diseases below the brachial plexus. The surgical approaches were by transaxillary approaches in 12 cases, supraclavicular approaches in 2 cases, and infraciavicular approaches in 2 cases. Result: There were 15 males and one female with an average age of 23.9 years (range:19$\∼$39). Rib anomalies were observed in four cases (25.0$\%$), but the others had no abnormal ribs. Right lesions were found in eight cases (50.0$\%$), left lesions in five cases (31.3$\%$), and bilateral lesions in three cases (18.7$\%$). The follow-up period was 9$\∼$26 months and recurrence rate was 12.5$\%$ (2/16). Complications were one case of ulnar nerve palsy, one case of persistent pain despite radiologic improvement and three cases of wound dehiscence due to fat necrosis and hematoma. Conclusion: Although the choice of treatment in patients with TOS has been disputed, patients who have no response with proper physical therapies can benefit from the surgical treatment which may help patients to return to normal daily activity in shorter period of time.