• Human Ecology Research
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• v.54 no.6
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• pp.565-574
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• 2016

This research examined the trajectories of peer rejection in preschool children. This study also investigated the gender differences in the intercept and slope of the trajectories for peer rejection along with the influences of aggression, withdrawal and language ability on the trajectories of peer rejection. A latent growth curve model investigated peer rejection in 3 to 5 year olds. Three hundred and thirteen 3-year-old children were recruited from five preschools and 14 daycare centers. The children's language ability was measured by a Wechsler Preschool and Primary Scale of intelligence verbal test and teachers completed measurements for aggression and withdrawal. A peer nomination inventory was used to assess peer rejection. Children were asked to nominate three classmates who they do not like to play with. The research findings showed that peer rejection decreased during the preschool years. Compared with girls, boys showed higher levels of peer rejection and a slower change rate of peer rejection. Girls who were aggressive showed high levels of peer rejection and a slow change rate of peer rejection. Moreover, girls who had a high levels language showed low levels of peer rejection and a slow change rate of peer rejection. These findings imply that language ability could be a protective factor of peer rejection for girls.

• Structural Engineering and Mechanics
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• v.53 no.6
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• pp.1183-1200
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• 2015

Reinforcement corrosion can cause serious safety deterioration to aging concrete structures exposed in aggressive environments. This paper presents an approach for reliability analyses of deteriorating reinforced concrete structures affected by reinforcement corrosion on the basis of the representative symptoms identified during the deterioration process. The concrete cracking growth and rebar bond strength evolution due to reinforcement corrosion are chosen as key symptoms for the performance deterioration of concrete structures. The crack width at concrete cover surface largely depends on the corrosion penetration of rebar due to the expansive rust layer at the bond interface generated by reinforcement corrosion. The bond strength of rebar in the concrete correlates well with concrete crack width and decays steadily with crack width growth. The estimates of cracking development and bond strength deterioration are examined by experimental data available from various sources, and then matched with symptom-based lifetime Weibull model. The symptom reliability and remaining useful life are predicted from the predictive lifetime Weibull model for deteriorating concrete structures. Finally, a numerical example is provided to demonstrate the applicability of the proposed approach for forecasting the performance of concrete structures subject to reinforcement corrosion. The results show that the corrosion rate has significant impact on the reliability associated with serviceability and load bearing capacity of reinforced concrete structures during their service life.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.13 no.1
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• pp.77-81
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• 1991

The melanotic neuroectodermal tumor of infancy(MNTI) is a rare childhood neoplasm with a clinical presentation. Because of its rapid growth pattern and bone resorption, the lesion can be mistaken for a malignant neoplasm. Although an aggressive growth rate and radiographic appearance, the MNTI almost always behaves in a benign fashion and can be treated with total excision. We presented the MNTI occured in the left maxillary alveolar ridge of 5 month old female infant. showing bluish enlargenent of alveolar mucosa with the displacement of central decidious incisor. And after the surgical excision of the mass, there is no recurrent tendency.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.34 no.4
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• pp.498-502
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• 2008

Ameloblastoma is the most common aggressive benign odontogenic tumor of the jaws. Because of slow growth and tendency to local invasion of bone and soft tissue, high rates of recurrence are common. The treatment for ameloblastoma is still controversial and poses some special problems in children. Because of growth of the jaw and the different incidence, prognosis of the tumor make the surgical consideration different from adults. Radical resection cause facial deformity, jaw abnormal movement and masticatory disturbance especially to child and adolescents. So conservative treatment as enucleation, curettage is acceptable initial treatment of ameloblastoma in children who can be followed up in a precise, detailed manner. This report describes a case of unilocular plexiform ameloblastoma treated by enucleation and curettage followed by marsupialization.

• Journal of East Asia Management
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• v.5 no.1
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• pp.75-90
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• 2024

About 100 years after the start of mass production by American car maker Ford in 1913, the automobile industry has come to a major transformation in 100 years. In this transformation period, automakers are facing the biggest challenge of converting power sources, the basis of automobiles, from existing internal combustion engines to electric vehicles. Hybrid vehicles have been released in Japan since the late 1990s, and changes in automobile power sources have occurred early. In order to gain global leadership in hybrid vehicles, Japanese automakers and the Japanese government joined forces to promote the growth of the domestic hybrid vehicle market. The government has implemented a policy to substantially subsidize the high price of hybrid cars compared to internal combustion engine cars by providing purchase subsidies and tax benefits to buyers. Toyota has increased its line-up of hybrid cars around the Prius and has further strengthened communication with customers for the sale of hybrid vehicles. As a result of continuing these efforts for about 20 years, the percentage of Japan's hybrid vehicle market in 2022 reached 51% for passenger cars. Recently, each country has been setting and promoting aggressive goals for electric vehicles that require a wider range of physical and institutional infrastructure than hybrid vehicles. This study aims to assess the growth of electric vehicles by looking at the trend of hybrid vehicles and how they've been distributed in the Japanese market.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.23 no.2
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• pp.197-200
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• 2001

We described two cases of odontogenic keratocysts of the maxilla. Odontogenic keratocysts (OKCs) are jaw cysts with a proclivity for local invasion and recurrence. Clinically, OKCs are characterized by aggressive, local growth. The diagnosis of mandibular OKC is based on physical examination and plain film radiographic findings. However, histopathological confirmation is required to make the diagnosis with certainty. The molar regions of the mandible and maxilla are the principal primary locations. The maxillary antrum is also a common site. Initial therapy is typically enucleation with or without extraction of the associated teeth. Long-term follow-up is necessary because of the aggressive nature and recurrence rate of OKCs.

• International Journal of Oral Biology
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• v.42 no.1
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• pp.33-38
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• 2017

Background: Periodontitis is an inflammatory disease characterized by the breakdown of tooth-supporting tissues, leading to tooth loss. Aggregatibacter actinomycetemcomitans are major etiologic bacterium causing aggressive periodontitis. Ursodeoxycholic acid (UDCA), a hydrophilic gall bladder acid, has been used as an effective drug for various diseases related to immunity. The aim of this study was to investigate the effect of UDCA on the inflammatory response induced by A. actinomycetemcomitans. Methods: A human acute monocytic leukemia cell line (THP-1) was differentiated to macrophage- like cells by treatment with phorbol 12-mystristate 13-acetate (PMA) and used for all experiments. The cytotoxic effect of UDCA was examined by MTT assay. THP-1 cells were pretreated with UDCA for 30 min before A. actinomycetemcomitans infection and the culture supernatant was analyzed for various cytokine production by ELISA. The effect of UDCA on bacterial growth was examined by measuring optical densities using a spectrophotometer. Results: UDCA showed no cytotoxic effect on THP-1 cells, up to $80{\mu}M$ Ed highlight: Please confirm technical meaning. UDCA pretreatment inhibited the A. actinomycetemcomitans-induced $IL-1{\beta}$, $TNF-{\alpha}$, and IL-17A secretion in a dose-dependent manner. UDCA also inhibited IL-21 production at $60{\mu}M$. The production of IL-12 and IL-4 was not influenced by A. actinomycetemcomitans infection. Conclusion: These findings indicate that UDCA inhibits the production of inflammatory cytokines involved in innate and Th17 immune responses in A. actinomycetemcomitans-infected THP-1- derived macrophages, which suggests its possible use for the control of aggressive periodontitis.

• Korean Journal of Poultry Science
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• v.46 no.3
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• pp.155-160
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• 2019

The Korean Hanhyup broiler has commercialized native meat-type chicken. This study aimed to determine the effects of two types of litter material-sawdust and rice husk, and gender on the Korean Hanhyup broiler. Chicks (n=416) were randomly assigned in a $2{\times}2$ factorial design by type of litter material and gender. The behavior of chicken's was monitored continuously for 12 hours during the $1^{st}$ through $8^{th}$ week of age. The time spent on standing, sitting, and walking and the frequency of drinking, feeding, preening, dust bathing, flapping, and aggressive pecking, and pecking of chicken's behavior were recorded. The behavior of chickens during the starter (1 to 4 weeks) and finisher period (5 to 8 weeks) was compared to observe the changes upon maturity. Our results indicate that litter material type and gender have no effect on the behavior of chickens. However, aggressive pecking and pecking caused increment in the rice husk as compared to sawdust (P<0.05). Sawdust as litter material for bedding was found to be better than rice husk with respect to Korean Hanhyup broiler behavior.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.13 no.5
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• pp.1-11
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• 2010

It is very difficult to control the expansion of reed at a wetland ecological park due to their aggressive reproduction capability. Therefore, proper topography and wetland hydrology should be provided before the construction of a wetland ecological park. Appropriate measures should be taken at the initial stages to prevent reed expansion. Field experiments were conducted at the newly constructed wetland ecological park for 15 months to develop methods to control the reproduction and expansion of Phragmites communis. A complete shading method had the best effect on the prevention of reed reoccurrence among other methods. Complete removal of the rhizomes controlled the reed growth to a greater extent than cutting the aboveground shoots. Water-level manipulation was also better than a half-shading method for the prevention of reed reproduction. These results indicated that soil properties and edge effects can influence the reed growth. Cutting only the aboveground shoots facilitates the growth of reed. These results suggest that reed control should be implemented repeatedly and an alteration in the wetland topography and hydrology may be more effective in the long term. Combination of treatments such as water-level management with shading should be considered to control the growth of reed. Adoptive management for created or restored ecosystem might be considered for accomplishment of its original purpose.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.11
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• pp.5915-5916
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• 2012

Human epidermal growth factor receptor (HER) 2 overexpression, observed in 20-25 percent of invasive breast cancers, is well known to be associated with a more aggressive phenotype and poor prognosis, with resistance to certain chemotherapeutic agents. The majority of patients with metastatic breast cancer who initially respond to trastuzumab, demonstrate disease progression within 1 year of treatment initiation. Furthermore, lack of response in some patients and relapse during the course of therapy, continue to challenge researchers and clinicians. A better understanding of the fundamental mechanisms of trastuzumab action is required so that new therapies directed at HER2 can be developed. We present here findings for mechanisms, both of Trastuzumab action and clinical resistance or escape.