• Journal of Plant Biotechnology
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• v.50
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• pp.142-154
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• 2023

Plant abscission is a natural process in which plant organs or tissues undergo detachment, a strategy selected by nature for the disposal of nonessential organs and widespread dissemination of seeds and fruits. However, from an agricultural perspective, the abscission of seeds or fruits represents a major factor that reduces crop productivity and product quality. Therefore, during the crop domestication process in traditional agriculture, mutants exhibiting suppressed abscission were selected and crossbred, thereby enabling the production of modern crop varieties such as rice, tomatoes, canola, and soybeans. These crops possess a unique trait of retaining ripe fruits or seeds in contrast to disposal via abscission. During the previous century, research on quantitative trait loci along with genetic and molecular biological studies on Arabidopsis thaliana have elucidated various cell biological mechanisms, signaling pathways, and transcription regulators involved in abscission. Additionally, it has been revealed that various hormone signals, which are involved in plant growth, play crucial roles in modulating abscission activity. Researchers have developed several chemical treatments that target these hormones and signal transduction pathways to enhance crop yields. This review aimed to introduce the previously identified signal transduction pathways and pivotal regulators implicated in abscission activity. Moreover, this review will discuss the future direction of research required to investigate crop abscission mechanisms for their potential application in smart farming and other areas of agriculture, as well as areas within model systems that require extensive research.

• Information Systems Review
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• v.18 no.4
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• pp.69-88
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• 2016

Nowadays, organizations have adopted Smart Work to efficiently manage tasks, such as electronic document approval, customer management, and site inspection, without spatial-temporal constraints. Smartphones, which are commonly used in Smart Work, enable individuals to perform their jobs anytime and anywhere, thus blurring the boundary between work and non-work. To solve the problem of blurred work/non-work boundaries, a construct of self-control and affective factors needs to be considered because business style is changed from command to autonomy in the Smart Work context. Moreover, employees can convey their emotions easily over smartphones. Recent marketing studies have analyzed consumers' behavior based on the combination of cognitive, affective, and behavioral components, and researchers of information systems are also interested in these factors. However, previous research has some limitations, such as not classifying factors into cognitive, affective, and behavioral as well as not covering all three factors. Therefore, we explore the roles of cognitive, affective, and behavioral components in emotional exhaustion and education performance, and conduct a survey on undergraduate and graduate students, who are the major users of smartphones. Findings show that when individuals improve their cognitive capability (self-control) and usage experience (smartphone communication and internet usage), they can decrease emotional exhaustion and increase education performance. In the role of affective capability, increasing education performance is partially accepted. These results imply that organizations should not focus on controlling the usage of smartphones but on promoting appropriate smartphone usage.

• Composites Research
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• v.37 no.3
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• pp.238-245
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• 2024

In this study, as part of the development of a monitoring system for the efficient maintenance of steel pipes, an experimental study was conducted to evaluate the performance of steel pipes treated with modified polyethylene coating. In the case of the conventional mechanical pre-coating method, there was a deterioration in polyethylene adhesion during expansion testing, which led to the application of a chemical pre-treatment process using a calcium-mixed phosphate zinc film to resolve this issue. SEM and EDX analyses showed that the densest structure was observed at a Zn/Ca ratio of 1.0, and improved heat resistance compared to the conventional method was confirmed. Additionally, to prevent coating detachment during expansion, an evaluation of adhesion and elongation was conducted on steel pipes with modified polyethylene coating, incorporating materials such as elastomers based on maleic anhydride grafting, metal oxides, blocking agents, and slip agents. Experimental results showed that the specimen (S4) containing all modified materials exhibited more than a 25% performance improvement compared to the specimen (S2) containing only metal oxides. Lastly, the development and performance evaluation of wedge-shaped socketing and pressing wheels, which are part of the pipe fixing accessories, were conducted to prevent surface coating damage on the completed pipes.

• Journal of Periodontal and Implant Science
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• v.29 no.2
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• pp.311-326
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• 1999

This study was investigated to observe the effect of Treponema denticola(TDC) and Treponema lecithinolyticum(TLC) on cultured human periodontal ligament cells. Several experiments were performed including MTT test for the inhibition effect of cell proliferation, LDH test for the cytotoxicity , gelatin zymography for the gelatinase activation and observation of cell morphology change using the phase-contrast microscopy. The results were as follows. 1. The effect of concentration on cell proliferation with time showed an inhibitory effect at high concentration $(150{\mu}g/well)$ for TLC and at low concentration( $9.4{\mu}gwell$ ) for TDC. 2. The effect of time on cell proliferation with concentration showed an inhibitory effect at $150{\mu}g/well$ on 2-day incubation for TLC and at $9.4{\mu}g/well$ on 2-day incubation for TDC. 3. The effect of heat-treated TDC and TLC on the inhibition of cell proliferation showed the difference in the heat-treated group compared to the non-heat treated group for TDC, whereas no difference was found for TLC. 4. The morphological changes which were observed from the phase-contrast microscopy showed the difference in the test group compared to the control group. The loss of spindle-like appearance, cell-to-cell detachment and inhibition of cell proliferation were observed. 5. There was no difference of the cytotoxicity effect between the test group and the control group in the LDH test. 6. The active form of progelatinase A with molecular weight 72kDa was activated in both TDC and TLC on the gelatin zymography. Regarding to the above results, TDC and TLC have an effect on periodontal ligament cells by playing an inhibitory role in cell proliferation and appears to activate progelatinase A which degrades type IV collagen.

• The Korean Journal of Nuclear Medicine
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• v.33 no.5
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• pp.439-451
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• 1999

Purpose : It is important to differentiate malignant from benign lesions of intraocular masses in choosing therapeutic plan. Biopsy of intraocular tumor is not recommended due to the risk of visual damage. We evaluated the usefulness of F-18-FDG PET imaging in diagnosing intraocular neoplasms. Materials and Methods: F-18-FDG PET scan was performed in 13 patients (15 lesions) suspected to have malignant intraocular tumors. There were 3 benign lesions (retinal detachment, choroidal effusion and hemorrhage) and 10 patients with 12 malignant lesions (3 melanomas, 7 retinoblastomas and 2 metastatic cancers). Regional eye images ($256{\times}256$ and $128{\times}128$ matrices) were obtained with or without attenuation correction. Whole body scan was also performed in eight patients (3 benign and 6 malignant lesions). Results: All malignant lesions were visualized while all benign lesions were not visualized. The mean peak standardized uptake value (SUV) of malignant lesions was $2.64{\pm}0.57g/ml$. There was no correlations between peak SUV and tumor volume. Two large malignant lesions ($> 1000 mm^3$) showed hot uptake on whole body scan. But two medium-sized lesions ($100-1000mm^3$) looked faint and two small ($<100mm^3$) lesions were not visualized. The images reconstructed with $256{\times}256$ matrix showed lesions more clearly than those with $128{\times}128$ matrix Conclusion: F-18-FDG PET scan is highly sensitivity in detecting malignant intraocular tumor For the evaluation of small-sized intraocular lesions, whole body scan is not appropriate because of low sensitivity. A regional scan with sufficient acquisition time is recommended for that purpose. Image reconstruction in matrix size of $256{\times}256$ produced clearer images than the ones in $128{\times}128$, but it does not affect the diagnostic sensitivity.

• Korean Journal of Ecology and Environment
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• v.39 no.1 s.115
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• pp.100-109
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• 2006

This study evaluated the effects of water velocity, substrates, and phosphorus concentrations on the growth of filamentous periphytic algae (FPA) in the two types of artificial channel systems using treated wastewater. Controlled parameters included 5 ${\sim}$ 15 cm $s^{-1}$ for the water velocity; 10 and 20 mm wire meshes, natural fiber net, gravel and tile for the substrates: and 0.05 ${\sim}$ 1.0 mgP $L^{-1}$ for the P concentration. Algal growth rate of FPA was compared using both chi. a and dry weight change with time. Under the controlled water velocity range, the growth of FPA increased with the velocity, but the maximum growth rate was shown in the velocity of 10 cm $s^{-1}$. The substrate that showed the maximum growth of FPA differed between the artificial channel and indoor channel, due to the influence of suspended matters which caused the clogging of the meshed substrates. Under the controled range of P concentration, the growth rates of all three FPA species (Spirogyra turfosa, Oedogonium fovelatum, Rhizoclonium riparium) increased with the P increase, but they showed the differential growth rates among different P concentrations. The results of this study suggest that under the circumstance having an large amount of nutrients FPA develop the biomass rapidly and that even a little increase over the threshold velocity causes the detachment of filamentous periphytic algae. Thus, FPA dynamics in eutrophic streams, such as those receiving treated wastewater, seem to be sensitive to the water velocity. On the other hand, detached algal filaments could deteriorate water quality and ecosystem function in receiving streams or down-stream, and thus they need to be recognized as an important factor in water quality management in eutrophic streams.

• Clinical and Experimental Pediatrics
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• v.52 no.6
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• pp.674-679
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• 2009

Purpose : The authors aimed to analyze the long-term effects of treatments, especially external beam radiotherapy (EBRT), in bilateral retinoblastoma patients. Methods : This retrospective study analyzed the medical records of 22 bilateral retinoblastoma patients who were registered between October, 1987 and October, 1998 and followed-up for more than 10 years. They were treated by enucleation, EBRT, and systemic chemotherapy. Age at diagnosis, sex, delay prior to treatment, Reese-Ellsworth (RE) classification, and the local treatment modalities were analyzed in relation to recurrence-free survival (RFS) and complications. Results : Median age at diagnosis was 7.0 months (range 1.7-31.6 months). Leukocoria was the most common presenting feature. Two patients had a familial history. The RE classifications of the 44 eyes were group II in 4, III in 14, IV in 4, and V in 22. At the end of a median follow-up period of 141 months (range 55-218 months), 20 patients were alive. The 10-year ocular survival rate of the 44 eyes was $56.8{\pm}7.5%$. The 10-year RFS and ocular survival rate of the 29 eyes treated by combined EBRT and chemotherapy were 75.9% and 86.2%, respectively. Treatment delay (>3 months) was found to be related to higher risk of recurrence. Complications after EBRT were cataract, retinal detachment, phthisis bulbi, and facial asymmetry. No patient developed a second malignancy during the follow-up period. Conclusion : Early detection and prompt treatment can increase ocular survival rates. In addition, careful attention should be paid to possible long-term sequelae in these patients.

• Korean Journal of Psychosomatic Medicine
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• v.25 no.1
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• pp.73-85
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• 2017

Objectives : In this study I made investigations how 'strange hunger' and 'compulsive overeating' threatening the ego could be resolved and healed. And I aim to present a healing model of psychotherapy and analysis as one of methods of treatment for 'eating disorder'. Methods : The analysands of this study were outpatients who visited the department of psychiatry of Yong-In Mental Hospital from March 2008 to February 2017 with 'hunger' and 'compulsive overeating' as their chief complaints. This study is based on the detailed records of the process of analysis including dreams and visions. Results : 1) Throughout the process of analysis that explore both consciousness and unconsciousness(dream, vision), hunger and compulsive overeating is improved and healed in all analysands. 2) The Imago of 'Snake' appeared in dreams and visions of all analysands. 3) By suffering impulse rather than acting it out, impulse transformes itself into 'Imago'. As impulse transforms into 'Imago' and reveals the 'meaning' of it, ego-threatening power of impulse weakens and mood is calmed. And as a result, synthesis of consciousness and unconsciousness and creative transformation of personality can be possible. Conclusions : In some people, 'hunger' and 'compulsive overeating' are 'creative impulses' that aim 'Self-realization' which can be fruited as creative transformation of personality and as creative transformation in the relation with the world. 'Creative impulses', which often can be experienced as instinctive impulse or emotional suffering unless ego realizes the meaning, reveal the meaning in dreams or visions through 'Imago' and 'Symbol'.

• The Journal of Art Theory & Practice
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• no.6
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• pp.77-99
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• 2008

The purpose of this study is to show that the reason behind the ambivalent characteristic displayed in Niki de Saint Phalle's works is in her trauma and how such characteristic can be extracted from her works. During her creative years, Saint Phalle worked on various materials from different genres such as assemblages, shooting paintings, a series on Bride and Monster, 'Nana', 'Tarot Garden'and public sculptures. One commonality found among her various works is the ambivalent characteristic that contains contrasting elements simultaneously. Saint Phalle suffered a terrible psychological damage inflicted by her parents during her childhood. Specifically, she was sexually assaulted by her father and emotionally neglected by her mother, the trauma that affected her for the rest of her life. As a result, she came to develop extreme love- hate relationships with her parents and this became the main reason for the ambivalent characteristic displayed in her works. The love-hate relationship Saint Phalle developed can be identified through various researches done on the subject of the affect of sexual assault. It is common for incest victims to develop ambivalent feelings towards the perpetrator and Saint Phalle was no exception. Dissociation disorder and a snake well explain the trauma from her father. It is a generally accepted belief in the field of psychology that dissociation disorder commonly occurs to children who experience incest. And dissociation disorder is similar to the characteristic of ambivalence in the sense that a single entity contains more than two contrasting elements at the same time. In addition, the amputated doll objects used in her assemblages coincide with the expression of body detachment of people with dissociation disorder. These facts clearly indicate that the trauma from her father is showing through in her works. A snake is a subject matter that reflects the ambivalent tendency of Saint Phalle that resulted from her trauma. She remembers her father's rape as an image of a snake which is related to a phallic symbol in mythology or art reflecting her trauma. Moreover, she displays a similar pattern of ambivalent emotion like love and hate or fear towards a snake and her father. This is also confirmed by her portrayal of a snake as a monster or reversely as a creature with fundamental vitality in her works. The lack of affection from her mother can be explained by her mother's maternal deprivation. It appears that Saint Phalle's mother possessed all the causes for maternal deprivation such as maternal separation, personality disorder and inappropriate attitude towards child rearing. Especially, a study that shows mother's negative attitude towards child breeding tends to increase dissociation experience of children is another important evidence that supports Saint Phalle's dissociation tendency. These traces of Saint Phalle's trauma are clearly revealed in her assemblages and shooting paintings. The violent objects in her assemblages such as a hammer, razor, nail represent the rage and defensiveness towards her father. The objects such as fragments of broken plates of feminine patterns, pots and mirrors that her mother used symbolize the affection towards her mother. On the other hand, the destructed objects can be interpreted as her hate and resentment towards her mother. Shooting paintings contain her extreme fury and hate. Things such as acts of shooting and the image associated with blood after shooting are blunt expressions of her bursts of emotions. I have tried to define and classify the ambivalent characteristics shown in her assemblages and shooting paintings as hate, rage, violence, calm, love and pleasure according to the frame of Thanatos and Eros. Out of the six, hate, rage, violence and clam are associated with Thanatos while love and pleasure are associated with Eros and they correspondingly form an ambivalent structure. These ambivalent characteristics can be found in her assemblages and shooting paintings. The objects in her assemblages such as a razor, saw, hammer imply hate, rage, violence and the silence felt throughout her works represent calmness. And, as mentioned, the feminine objects can be seen as symbolizing love. In shooting paintings, hate, rage, violence can be found in the use of force and in the traces of watercolor after shooting, and a sense of pleasure in her feelings of catharsis after her shooting. Moreover, a shielded calmness can be found on the plywood all covered with plaster before the shooting. This study looked into the ambivalent characteristic of Saint Phalle's works by examining her trauma to find its correlation, and a meaning of this study can be found from the fact that it refocused the origin of Saint Phalle who is generally known as a feminist artist. Additionally, a meaning of the study can be found also from the fact that it examined the ambivalent characteristics of her works through a frame of Thanatos and Eros.

• Journal of fish pathology
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• v.5 no.2
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• pp.93-118
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• 1992

The research was carried out to examine the chronic toxic effects of nitrite on the Japanese eel, Anguilla japonica by neans of histological observations. Young eel, 10.8g mean body weight. were exposed to 6 different concentrations of nitrite(1, 5, 10, 20, 30 and 40ppm) for 10 weeks. Each concentration was treated under 5 different levels of pH(5.5, 6.0, 6.5, 7.0 and 7.5) and each of these treatment was tested at 2 different temperature regimes($25^{\circ}C$ and $30^{\circ}C$). Proper concentration of nitrite was made by $NaNO_2$ and proper pH levels were made by the combinations of 0.1M $KH_2PO_4$ and 0.1M $NaHCO_3$. Histopathological test of gill tissues were made along with the test of the formation of thrombocystes and chloride cells on the gill filaments. At the lower pH levels, mucus secretion from the gill was incrased as the nitrite concentration increased. As the level of nitrite increased the number of chloride cells on the gill filament were decreased. Most of the remained chloride cells were observed only at the terminar part of the gill filament at 40ppm of nitrite. Degeneration of gill tissues were observed when nitrite levels were over 10ppm along with detachement and sweption of the epithelial cells of the gill lamellae. Shrunken gill lamellae and formation of thrombosis in the capillaries of gill lamellae were also observed. When temperature goes higher at the higher level of nitrite, necroses in the gill lamellae was increased. At the lower than 10ppm of nitrite, degeneration of gill lamellae was occured at the beginning of the test period but regenerated later. Negative effects of nitrite on the growth of young eel was started between 5~10ppm at the pH level of 7.0 and 7.5. Thrombosis formation were also started at this level. The safety concentration of nitrite at the pH levels of 7.0 and 7.5 on the small eel seems to be 1ppm. Thrombosis and gill lamella detachment and necrosis in the gill capillaries were not observed at this level. Chloride cells were appeared the whole part of the gill filament.