• Journal of Dental Rehabilitation and Applied Science
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• v.37 no.1
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• pp.48-60
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• 2021

Patients who have extruded anterior teeth and deep bite with pathologic tooth migration, it is necessary not only periodontal treatment for reduce inflammation, but also orthodontic treatment for intrusion of anterior teeth. However, it is difficult to place the orthodontic brackets due to the deep bite, and there is a problem that the extrusion of the posterior teeth occurs more easily than the intrusion of the anterior teeth biomechanically. In particular, in patients with long face, relative intrusion of the anterior teeth by extrusion of the posterior teeth causes the clockwise rotation of the mandible and makes the facial profile worse. Therefore the biomechanical consideration and appliance design that can block these problems are required from the treatment plan. This is a patient who had a deep overbite with extruded anterior teeth, treated by periodontal treatment and intrusion of mandibular anterior teeth using cute brackes and miniscrews, and resulted in favorable maintenance during 8-year retention.

• Journal of the Korea Concrete Institute
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• v.24 no.4
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• pp.481-490
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• 2012

Evaluation of chloride penetration is very important, because induced chloride ion causes corrosion in embedded steel. Diffusion coefficient obtained from rapid chloride penetration test is currently used, however this method cannot provide a correct prediction of chloride content since it shows only ion migration velocity in electrical field. Apparent diffusion coefficient of chloride ion based on simple Fick's Law can provide a total chloride penetration magnitude to engineers. This study proposes an analysis technique to predict chloride penetration using apparent diffusion coefficient of chloride ion from neural network (NN) algorithm and time-dependent diffusion phenomena. For this work, thirty mix proportions with the related diffusion coefficients are studied. The components of mix proportions such as w/b ratio, unit content of cement, slag, fly ash, silica fume, and fine/coarse aggregate are selected as neurons, then learning for apparent diffusion coefficient is trained. Considering time-dependent diffusion coefficient based on Fick's Law, the technique for chloride penetration analysis is proposed. The applicability of the technique is verified through test results from short, long term submerged test, and field investigations. The proposed technique can be improved through NN learning-training based on the acquisition of various mix proportions and the related diffusion coefficients of chloride ion.

• Korean Journal of Heritage: History & Science
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• v.40
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• pp.387-411
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• 2007

The analysis of ancient DNA (aDNA) has become increasingly considerable anthropological, archaeological, biological and public interest. Although this approach is complicated by the natural damage and exogenous contamination of a DNA, archaeologists and biologists have attempted to understand issues such as human evolutionary history, migration and social organization, funeral custom and disease, and even evolutionary phylogeny of extinct animals. Polymerase chain reaction(PCR) is powerful technique that analyzes DNA sequences from a little extract of an ancient specimen. However, deamination and fragmentation are common molecular damages of aDNA and cause enzymatic inhibition in PCR for DNA amplification. Besides, the deamination of a cytosine residue yielded an uracil residue in the ancient template, and results in the misincorporation of an adenine residue in PCR. This promotes a consistent substitution (cytosine thymine, guanine adenine) to original nucleotide sequences. Contamination with exogenous DNA is a major problem in aDNA analysis, and causes oversight as erroneous conclusion. This report represents serious problems that DNA modification and contamination are the main issues in result validation of aDNA analysis. Now, we introduce several criterions suggested to authenticate reliance of aDNA analysis by many researchers in this field.

• Journal of Life Science
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• v.33 no.9
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• pp.703-712
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• 2023

Angiogenesis, the formation of blood vessels from pre-existing vessels, is a multistep process regulated by modulators of angiogenesis. It is essential for various physiological processes, such as embryonic development, chronic inflammation, and wound repair. Dysregulation of angiogenesis causes many diseases, such as cancer, autoimmune diseases, rheumatoid arthritis, cardiovascular disease, and delayed wound healing. However, the number of effective anti-angiogenic drugs is limited. Recent research has focused on identifying potential drug candidates from natural sources. For example, marine natural products have been shown to have anti-cancer, anti-oxidant, anti-inflammatory, antiviral, and wound-healing effects. Thus, this study aimed to describe the angiogenesis inhibitory effect of Hizikia fusiforms (brown algae) extract. The hexane extract of H. fusiformis has shown inhibitory effects on in vitro angiogenesis assays, such as cell migration, invasion, and tube formation in human umbilical vein endothelial cells (HUVECs). The hexane extract of H. fusiformis (HFH) inhibited in vivo angiogenesis in a mouse Matrigel gel plug assay. In addition, the protein expression of vascular endothelial growth factor (VEGF), mitogen-activated protein kinase (MAPK)/extracellular signal kinase, and AKT serine/threonine kinase 1 decreased following treatment with H. fusiformis extracts. Our results demonstrated that the hexane extract of H. fusiformis (HFH) inhibits angiogenesis in vitro and in vivo.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.13 no.1
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• pp.3-14
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• 2002

Childhood psychic trauma appears to be a crucial factor in the development of serious disorders both in childhood and in adulthood. Traumatized children show strong tendency to revisualize or re-feel a traumatic events. Play and behavioral reenactments are frequent manifestations of both the single blow and the long-standing traumas in childhood. Those children who suffer the results of single, intense terror appear to exhibit detailed memory, retrospective reworkings and misperceptions. In long-standing or repetitive trauma, children would show psychic numbing, self-hypnosis, dissociation and rage. Child's brain is undergoing critical and sensitive periods of differentiation. During this time, developing central nervous system is exquisitely sensitive to stress. Stressor-activated neurotransmitters and hormones can play major roles in neurogenesis, migration, synaptogenesis, and neurochemical differentiation. Internal opiate system operates in some trauma and causes the victim to fail to respond, to avoid, to shut off feelings. Evidence is also accumulating in traumatology that dysfuntion of locus coeruleus and ventral tegmental neucleus system leads to catecholamine receptors hypersensitivity. This change result in hypervigilance, increased startle, affective lability, and increased autonomic nervous system hyperreactivity. Another site of action of trauma on the brain is hypothalamic-pituitary-adrenal axis. Individuals with PTSD do not have enough cortisol to halt the alarm reaction. When children are exposed to long-standing extreme events, massive attempts to protect the psyche and to preserve the self are put into gear. These developmental traumas mobilize various kinds of defense mechanisms. Massive denial, dissociation, self anesthesia, identification with aggressor and aggression turned against the self often lead to profound character changes in the youngsters.

• Korean Journal of Environment and Ecology
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• v.34 no.2
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• pp.106-114
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• 2020

The development of transportation and the expansion of the pet market has become the main causes of the increase in the cross-border migration of non-native species. Moreover, recent sales over the Internet were a factor that has promoted pet trades. While the import of non-native species has been steadily increasing in the Republic of Korea, it is not clear how these imported species are traded and how large the trade is. Considering that most of the non-native species found in the wild are the results of release by humans understanding the present situation of pet trades can identify potential non-native species that can enter the wild. This study surveyed the number of species, frequency, and prices of non-native amphibians and reptiles sold in 25 online pet shops from January 22 to February 10, 2019. The results of the survey showed that a total of 677 species of non-native amphibians and reptiles were sold, and the Squamata group accounted for the largest part of them at 65.4% (443 species). The number of non-native amphibians and reptiles sold in online pet shops in 2019 was 2.1 times larger than the 325 species officially imported in 2015. The non-native amphibians and reptiles sold in most pet shops were Litoria caerulea (21 shops) and Correlophus ciliatus (24 shops). The lowest price for non-native amphibians and reptiles was 3,000 won, and the highest price was 100 million won for Rhacodactylus leachianus of Squamata. Among the non-native amphibians and reptiles sold in online pet shops, 11 species were found in the wild and were sold at relatively low prices. We confirmed that Mauremys reevesii, an endangered species class II and natural monument no. 453, and American bullfrogs (albino), an ecosystem disturbing species, were being sold in online pet shops. Moreover, 21.6% of the 677 non-native amphibians and reptiles sold in online pet shops were species designated as CITES. The results of this study can be the important reference data for understanding the status of non-native amphibians and reptiles that are imported and sold in Korea and evaluating and predicting the potential for them to enter the wild.

• Journal of the Korean Society of Radiology
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• v.82 no.2
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• pp.371-381
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• 2021

Purpose To evaluate the usefulness and effectiveness of bronchial occluders in the treatment of postoperative bronchopleural fistula (BPF). Materials and Methods The subjects of the study were six out of seven postoperative BPF patients who underwent surgery due to tuberculosis or lung cancer between 2009 and 2019. Each patient had a bronchial occluder inserted to treat BPF that occurred after surgery. Of the six patients, five had lung cancers and one had tuberculosis. Five were male and one was female; their ages ranged from 59 to 74 years, with an average of 69 years. The diagnosis of BPF was based on findings from bronchoscopy and CT, and treatment was initiated approximately 1 to 2 weeks after diagnosis. The technical and clinical success of the bronchial occluders in the treatment of BPF was evaluated. The study assessed the postoperative clinical effects of the occluders, survival duration, and additional treatments. Results All six patients were successfully treated. Clinical success was achieved in five patients, while partial clinical success was achieved in one; there was no clinical failure. No complications during the migration of the device or device perforations were observed. Two patients were diagnosed with BPF by CT, while four were diagnosed by bronchoscopy. Lobectomy, bilobectomy, and pneumonectomy were performed on two patients each. The periods between surgery and diagnosis ranged from 1 to 34 months; the average was 10 months. Four patients (59-103 days; an average of 80.5 days) died and two (313 days, 3331 days) survived. The causes of death were aggravation of the underlying disease (n = 2), pulmonary edema and pleural effusion (n = 1), and pneumonia (n = 1). Additional catheter drainage was performed in one patient, and a chest tube was maintained in two patients. Conclusion Bronchial occluders are useful and effective in the treatment of BPF after pulmonary resection.

• Journal of the Korean Geographical Society
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• v.29 no.1
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• pp.84-104
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• 1994

The migration of population into the city has been on the increase according as Korea has been industrialized repidly since the 1960's. And there is a steady decrease in rural population. Thus lack of the number of the students forced many elementary Schools to be abolished. The aim of this study is to grasp the abolition types and the regional characteristics with the subject region of Chungbuk province. From the viewpoint of the increasing abolition of the elementary schools, I think it is very important to understand how the elementary schools have been abolished so far and predict how the subject region will have been changed in geography. Data for this study are based on Annual Establishment-Abolition Situation of the Schools published by Chungbuk office of Education in 1992, and many Kinds of the statistical reports, and the interview with the related. The results are as follows: 1. By examining the change of the number of the elementary schools and students in Chnugbuk, the numder of the students had also decreased since 1969 and was less than the half in 1990. As the number of the schools began to decrease ten years later than the students began to, the abolition of the elementary schools has started in reality from 1980's. 2. The 72 elementary schools were aboilshed between 1980 and 1992: the principal school is 9.7%, the branch school is 90.3%. The most fifteen schools are abolished in Yongdong-county and Chechon-county, and the least one school is abolished in Chechon-city and Okchon-county, and there is no abolition in Chongju-city and Chungju-city: According to the type of the abolition process, the least seven principal schools are abolished, and the principal school is reorganized as a branch school and twenty eight branch schools are abolished, and the most thirty seven branch schools are abolished. 3. When special change of the abolition is classified into the first perio (1980-1986) and the second period (1987-1992), in the first period the principal and branch schools were abolished and they are 13.9% of total abolition. The abolition out of them by building a dam is 60%. The principal schools in the submerged area though they have many students, were abolished. In the second period sixty two branch schools are abolished and they are 86.1% of total abolition. The most fifteen schools are abolished in Yongdong-county, thirteen in Chechon-county, seven in Tanyang-county, six in Chongwon-county, five in Chungwon-county and Koesan-county. Unlike the first period, the schools were abolished in this period because the number of students was so small. In this period sixty branch schools were abolished. All the students in the abolished schools except six schools transfered to the principal schools. The 58 school authorities help the students attend school by bus or support the expenses for attending school after that. 4. The abolition types of city, county and myon are classified into five types by the number of the abolished schools. The most forty nine abolished schools in type II are 68.1 of the total abolition. The least three abolished ones in type I are 12.5%. Considering the relation between the abolition type ane the number of schools and students, the number of the schools, increased in type I, II, III, V except IV from 1980 and then have decreased by abolition since 1980, while the more students decreased than they did in 1970 and the more the abolished school increases, the less the students decreases. The average students per school decreased in every abolition type and the most students decreased in type IV. 5. Considering the relation between the abolition type and the regional characteristics, most abolished schools were located between 100m and 300m above the sea level and it is 71% of the total abolition. The region without the abolition is high in the ratio of the cultivate land, ratio of rice field, and the part-time farmer, but the region with many abolition is low in the ratio of cultivated land. As for the manufacturing there are the most city, county and myon in the abolition type in Youngdong-county and Chechon-county where the manufacturing ratio of employing is low but Chongju-city without the abolition is a region where the manufacturing ratio is high. Consequently the development of the manufacturing causes the population to emigation out and the decrease of the population leads the transport is difficult of access, the facilities sold after being abolished are not being used in many ways. 7. Take an example of Youndong-county where the most schools were abolished, I have examined the school district and the population characteristics of the abolition. Though there were more villages, households, populations in the region that is higher than low above the sea level, the schools were abolished. Therefore we know that above the sea level had a great effect on the abolition. As a result of the regional analysis of the abolition, many schools were abolished by the artificial buildings such as a dam in the early 1980's but the schools in the late 1980's were abolished ten years later after the students decreased. More schools were abolished in the region where the manufacturing industry didn't develop. And the higher the school position was above the sea level, the sooner the school was abolished. It is also proved that both the beautiful natural scenery and accessibility are the important factor in using the abolished facilities practically.