• Korean Journal of Culture and Social Issue
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• v.24 no.1
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• pp.1-27
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• 2018

The purpose of this study was to identify the persistent and dynamic association between bullying and victimization. Gender differences in patterns of school bullying was hypothesized based on the literature. Analysis were based on waves 3-6 of the Korea Children and Youth Panel Survey, a nationally representative data of primary and secondary school students in South Korea (N = 1,881). Autoregressive cross-lagged model was employed to identify the reciprocal association between bullying and victimization in longitudinal data. As hypothesized, regardless of gender, lagged effects were statistically significant between each time points such that current bullying caused future bullying and current victimization led to future victimization. However, there was no cross-lagged effects of current victimization on future bullying nor current perpetration on future victimization for both male and female youth. Findings from this study may have implications for designing policies against school bulling. Not only is short-term intervention for handling immediate psycho-social maladjustment important, but so are long-term plans that prevent youth from falling into continued perpetration and victimization in the system of school bullying.

• International Journal of Oral Biology
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• v.31 no.4
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• pp.113-118
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• 2006

In the primary sensory neuron of the mesencephalic trigeminal nucleus (MTN), the peripheral axon supplies a large number of annulospiral endings surrounding intrafusal fibers encapsulated in single muscle spindles while the central axon sends only a few number of synapses onto single ${\alpha}-motoneurons({\alpha}-MNs)$. Therefore, the ${\alpha}-{\gamma}$ linkage is thought to be very crucial in the jaw-closing movement. Spike activity in a ${\gamma}-motoneuron\;({\gamma}-MN)$ would induce a large number of impulses in single peripheral axons by activating many intrafusal fibers simultaneously, subsequently causing an activation of ${\alpha}-MNs$ in spite of the small number of synapses. Thus, the activity of ${\gamma}-MNs$ may be vital for modulation of jaw-closing movements. Independently of such a spindle activity modulated by ${\gamma}-MNs$, somatic depolarization in MTN neurons is known to trigger the oscillatory spike activity. Nevertheless, the trafficking of these spikes arising from the two distinct sources of MTN neurons is not well understood. In this short review, switching among multiple functional modes of MTN neurons is discussed. Subsequently, it will be discussed which mode can support the ${\alpha}-{\gamma}$ linkage. In our most recent study, simultaneous patch-clamp recordings from the soma and axon hillock revealed a spike-back-propagation from the spike-initiation site in the stem axon to the soma in response to a somatic current pulse. The persistent $Na^+$ current was found to be responsible for the spike-initiation in the stem axon, the activation threshold of which was lower than those of soma spikes. Somatic inputs or impulses arising from the sensory ending, whichever trigger spikes in the stem axon first, would be forwarded through the central axon to the target synapse. We also demonstrated that at hyperpolarized membrane potentials, 4-AP-sensitive $K^+$ current ($IK_{4-AP}$) exerts two opposing effects on spikes depending on their origins; the suppression of spike initiation by increasing the apparent electrotonic distance between the soma and the spike-initiation site, and the facilitation of axonal spike invasion at higher frequencies by decreasing the spike duration and the refractory period. Through this mechanism, the spindle activity caused by ${\gamma}-MNs$ would be safely forwarded to ${\alpha}-MNs$. Thus, soma spikes shaped differentially by this $IK_{4-AP}$ depending on their origins would reflect which one of the two inputs was forwarded to the target synapses.

• Journal of Korean Foot and Ankle Society
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• v.25 no.4
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• pp.149-156
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• 2021

Purpose: Given the lack of definite evidence-based guidelines in clinical practice, there may be a wide variation in treatment protocols for osteochondral lesions of the talus (OLT). Based on the Korean Foot and Ankle Society (KFAS) member survey, this study aimed to report the current trends in the management of OLT. Materials and Methods: A web-based questionnaire containing 30 questions was sent to all KFAS members in September 2021. The questions were mainly related to clinical experience and preferences in diagnosis, conservative, and surgical treatments for patients with OLT. Answers with a prevalence of ≥50% of respondents were considered a tendency. Results: Sixty-two (11.3%) of the 550 surgeons queried responded to the survey. The responses to 9 (30.0%) of the total of 30 questions established a tendency. Answers exhibiting a tendency were as follows; additional diagnostic tools except for plain radiograph (magnetic resonance imaging), most common conservative treatment method (oral medication, rest), most important radiological factor in decision making for surgical treatment and method (size of the lesion, ankle instability, loose bodies), most important patient factors in decision making for surgical treatment and method (age, activity or occupation), infrequently requiring posterior arthroscopy (less than 3%), most common revision surgery for failed bone marrow stimulation procedure (osteochondral autograft transplantation [OAT]), not requiring additional procedure for donor site in OAT, the main reason for unsatisfactory result after OAT (persistent pain without radiological abnormality), no generalization of autologous chondrocyte implantation or chondrogenesis using stem cells. Conclusion: This study presents updated information on current trends in the management of OLT in Korea. Both consensus and variations in the approach to patients with OLT were revealed through this survey. Since recent biologic efforts to regenerate cartilage have been unsuccessful, further studies to identify clinical evidence would be needed.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.9
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• pp.3851-3864
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• 2014

Cytokine research is currently at the forefront in cancer research. Deciphering the functions of these multiple small molecules, discovered within the cell and in intercellular spaces, with their abundance and pleotrophism, was initially a great challenge. Advances in analytical chemistry and molecular biology have made it possible to unravel the pathophysiological functions of these polypeptides/proteins which are called interleukins, chemokines, monokines, lymphokines and growth factors. With more than 5 million women contracting cervical cancer every year this cancer is a major cause of mortality and morbidity the world over, particularly in the developing countries. In more than 95% of cases it is associated with human papilloma virus (HPV) infection which is persistent, particularly in those with a defective immune system. Although preventable, the mere magnitude of prevalence of HPV in the world population makes it a dominating current health hazard. The discovery of cytokine dysregulation in cervical cancer has spurted investigation into the possibility of using them as biomarkers in the early diagnosis of cases at high risk of developing cancer. Their critical role in carcinogenesis and progression of cervical cancer is now being revealed to a great extent. From diagnostics to prognosis, and now with a possible role in therapeutics and prevention of cervical cancer, the cytokines are being evaluated in all anticancer approaches. This review endeavours to capture the essence of the astonishing journey of cytokine research in cervical neoplasia.

• Journal of Korean Society for Atmospheric Environment
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• v.29 no.5
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• pp.513-527
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• 2013

Recently, hazardous air pollutants (HAPs) have been of great concern in Korea, largely due to public awareness on the importance of their impacts on environmental health. A group of HAPs includes a large number of various chemicals such as VOCs, PAHs, PCBs, dioxines, furans, organochlorinated pesticides, and some heavy metals. These groups of pollutants are generally known to have genetic toxicity and to be persistent in the environment. In addition, most of chemicals belong to the category of HAPs are widely distributed not only in air, but also in water and soil environments, and has therefore undergone considerable scrutiny for the last three decades. In this article, environmental implications and management of HAPs in Korea will be reviewed, with a particular emphasis on the monitoring of HAPs in the ambient air. A number of field studies will be introduced, which were recently conducted in large urban and industrial areas. Based on the filed studies, eight pollutants have been suggested to be intensively managed as higher priority pollutants, which are benzene, 1,3-butadiene, formaldehyde, acrolein, trichloroethylene, benzo(a)pyrene, hexa-valent Cr, and $PM_{2.5}$. Finally, future directions for a mega scale project for comprehensive monitoring of ambient atmosphere in large urban areas will be suggested. Such an innovative project is believed to provide more realistic information on the nature of the population exposure, which can not be simply identified by emission inventories or source investigations. Therefore, any strategy for the management of HAPs should be developed by not only emission-based approaches, but also observation-based approaches.

• The Korean Journal of Physiology and Pharmacology
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• v.22 no.6
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• pp.649-660
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• 2018

Migraine is a neurological disorder characterized by recurrent and disabling severe headaches. Although several anticonvulsant drugs that block voltagedependent $Na^+$ channels are widely used for migraine, far less is known about the therapeutic actions of carbamazepine on migraine. In the present study, therefore, we characterized the effects of carbamazepine on tetrodotoxin-resistant (TTX-R) $Na^+$ channels in acutely isolated rat dural afferent neurons, which were identified by the fluorescent dye DiI. The TTX-R $Na^+$ currents were measured in medium-sized DiIpositive neurons using the whole-cell patch clamp technique in the voltage-clamp mode. While carbamazepine had little effect on the peak amplitude of transient $Na^+$ currents, it strongly inhibited steady-state currents of transient as well as persistent $Na^+$ currents in a concentration-dependent manner. Carbamazepine had only minor effects on the voltage-activation relationship, the voltage-inactivation relationship, and the use-dependent inhibition of TTX-R $Na^+$ channels. However, carbamazepine changed the inactivation kinetics of TTX-R $Na^+$ channels, significantly accelerating the development of inactivation and delaying the recovery from inactivation. In the current-clamp mode, carbamazepine decreased the number of action potentials without changing the action potential threshold. Given that the sensitization of dural afferent neurons by inflammatory mediators triggers acute migraine headaches and that inflammatory mediators potentiate TTX-R $Na^+$ currents, the present results suggest that carbamazepine may be useful for the treatment of migraine headaches.

• Journal of KIISE:Databases
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• v.33 no.5
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• pp.551-562
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• 2006

XML query caching for XML database-backed Web applications began to be investigated recently. Despite its practical significance, efficiency of the storage schemes for cached query results has not been addressed. In this paper, we deal with the storage schemes for XML query cache. A fundamental problem that needs to be considered in designing an efficient storage structure for XML query cache is that there exist performance tradeoffs between the two major types of operations on a cached query result. The two are (1) retrieving the whole of it to return the query result and (2) updating just a small portion of it for its incremental refresh against the updates done to its source. We propose eight different storage schemes for XML query cache, which are categorized into three groups: (1) the schemes based on the plain text file, (2) the schemes based on the persistent DOM (PDOM) file, and (3) a scheme employing an RDBMS. We implemented all of them, and compared their performance with each other. We also compared our proposal with a storage scheme based on a current state-of-the-art XML storage scheme, showing that ours is more efficient.

• International Journal of Oral Biology
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• v.33 no.3
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• pp.117-123
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• 2008

Reactive oxygen species (ROS) are toxic agents that may be involved in various neurodegenerative diseases. Recent studies indicate that ROS can act as modulators of neuronal activity, and are critically involved in persistent pain primarily through spinal mechanisms. In the present study, whole cell patch clamp recordings were carried out to investigate the effects of tert-buthyl hydroperoxide (t-BuOOH), an ROS, on neuronal excitability and the mechanisms underlying changes of membrane excitability. In current clamp condition, application of t-BuOOH caused a reversible membrane depolarization and firing activity in substantia gelatinosa (SG) neurons. When slices were pretreated with phenyl-N-tert-buthylnitrone (PBN) and ascorbate, ROS scavengers, t-BuOOH failed to induce membrane depolarization. However, isoascorbate did not prevent t-BuOOH-induced depolarization, suggesting that the site of ROS action is intracellular. The t-BuOOH-induced depolarization was not blocked by pretreatment with dithiothreitol (DTT), a sulfhydryl-reducing agent. The membrane-impermeant thiol oxidant 5,5-dithiobis 2-nitrobenzoic acid (DTNB) failed to induce membrane depolarization, suggesting that the changes of neuronal excitability by t-BuOOH are not caused by the modification of extrathiol group. The t-BuOOH-induced depolarization was suppressed by the phospholipase C (PLC) blocker U-73122 and inositol triphosphate ($IP_3$) receptor antagonist 2-aminoethoxydiphenylbolate (APB), and after depletion of intracellular $Ca^{2+}$ pool by thapsigargin. These data suggest that ROS generated by peripheral nerve injury can induce central sensitization in spinal cord, and t-BuOOH-induced depolarization may be regulated by intracellular $Ca^{2+}$ store mainly via $PLC-IP_3$ pathway.

• Journal of The Korean Association of Information Education
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• v.9 no.4
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• pp.617-625
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• 2005

With enforcement of information usage education since 1997, teachers have been given many different types of training to improve teacher's expertise. Especially, It has established distance education centers as an attempt to construct advanced training system in digital information society to solve the problems with current attendance-based training, and then its number has increased until now, total 53 institutes are on the list at the moment (Sep.2004). In this research, it has conducted a survey and analysis on educational contents and general management state, based on the curriculum of distance training center, for making its quality improvement plan including mutual contentment of both provider and demander for elementary school teachers. Examining the survey, it is expected for providers to accommodate persistent feedback to reflect periodically changing needs and various interest. From users' perspective, they wanted varied programs to choose in many other subjects for enhancing its expertise, rather than taking classes just for evaluation.

• Culinary science and hospitality research
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• v.23 no.5
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• pp.92-100
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• 2017

The purpose of this study was to analyze the current status of 30 restaurants targeted for customized-visit consulting. For this process, experts visited restaurants and conducted consulting to improve the effectiveness of management for restaurants. A frequency analysis was used for general details, and a questionnaire survey was conducted to consult employees and customer groups. The analysis and consulting results were as follows: Firstly,menu need to be improved through restaurants' sanitary state and menu quality improvement. New menu should be developed through continuous training for restaurant operators, the relevant organizations, and cooking skill experts. Secondly, restaurants' cooking skill and knowledge should be secured by training of restaurant operators from the relevant organizations and experts to acquire cooking skills. In conclusion, restaurants' capability needs to be consolidated through persistent and cyclical process to maintain competitive menus and cooking skills. The results also showed that employee group's MOT, foods, menu, and facility education/training should be fortified. In order to reinvigorate the restaurant industry, marketers need to offer continuous education/training and consulting for employees to improve their satisfaction.