• Proceedings of the Korean Institute of Building Construction Conference
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• 2023.11a
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• pp.93-94
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• 2023

This study evaluated the mechanical properties and microstructure of calcium silicate cement based paste according to carbonation curing conditions. As a result, both compressive strength and carbonation depth increased with the carbonation curing period.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2023.11a
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• pp.79-80
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• 2023

After the Second Industrial Revolution, as global warming caused by environmental issues has intensified, the CO₂ emissions from the cement industry have become an urgent challenge. Therefore, this study aimed to reduce and utilize CO₂ emissions by using CO₂-reducing Calcium Silicate Cement.

• Proceedings of the KOR-BRONCHOESO Conference
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• 1993.05a
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• pp.91-91
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• 1993

The anatomical study of whole organ sections was used necessarily for understanding the histopathological anatomy, and routes of neoplastic spread. Ten whole-organ cancerous larynges were axially sectioned and its histopathologic findings were compared with the MRI findings. This study is designed to evaluate the anatomical relationships of the tumor to the laryngeal structure & possible spread of cancer of the larynx.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.12
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• pp.1815-1819
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• 2009

Based on the soft and rigid extents, tissues are mainly divided into two groups in mammals, soft tissues including heart, lung, kidney and brain, and hard tissues including tendon, cartilage, teeth and bone. Among various tissues, bone, a dynamic rigid organ, is continuously remodeled by the opposing functional activity between bone formation by osteoblasts and bone destruction by osteoclasts. Bone protects the soft tissues and provides mineral reservoirs, which can supply the mineral needs of other soft tissues to normally maintain cellular function. While calcification in bone is an important action to fundamentally support the body and protect the soft tissues, calcification in soft tissues, including the heart, aorta, kidney, lung and spleen, results in severe organ damages, eventually causing sudden death. A growing body of evidence indicates that the osteoporotic patient who are aging, post-menopausal, diabetes and chronic kidney disease simultaneously represent a high clinical incidence of soft tissue calcification, illustrating a link between soft tissue calcification and bone decalcification (osteoporosis). This study will review what is currently known about the connection between bone decalcification and soft tissue calcification.

• The korean journal of orthodontics
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• v.30 no.6 s.83
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• pp.669-675
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• 2000

Excessive production of parathyroid hormone causes bony disorder such as periosteal bone resorption and bone pain due to excessive skeletal demineralization. A Class III facial deformity case with generalized root resorption presented bete was fumed out to be due to hyperparathyroidism. Clinical and cephalometric analysis revealed a straight skeletal profile with a retruded maxilla and a prognathic mandible. The x-ray findings demonstrated generalized root resorption of entire dentition to different degree. There also appeared osteoporosis like immature trabecular structure with the evidence of ground glass appearance. Serum test showed elevated 1evel of parathyroid hormone and growth hormone. Change of cranial growth by hyperparathyroidism can be dependent up(In a decreased bone apposition in viscerocranial growth site and abnormalities in cranial suture growth. It is possible to hypothesize that growth retardation of maxilla at least partially be accounted lot hyperparathyroidism. Therefore, regarding to the definite etiology of skeletal Class III and orthodontic treatment planning considering root resorption and osteoporosis, the early diagnosis for the hyperparathyroidism should be carefully carried by clinical and laboratory studies.

• The korean journal of orthodontics
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• v.27 no.1
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• pp.141-155
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• 1997

The purpose of this study was to evaluate the effectiveness of the Nd:YAG laser and the Er:YAAG laser on etching enamel for direct bonding of orthodontic bracket. The advantages of laser etching rather than conventional acid etching are to reduce the subsurface demineralization rate, to inhibit the spillage of acid onto uninvolved ""its of enamel, and to save the clinical manipulation time involving drying, trashing and drying again. 189 freshly extracted human premolars were prepared for this research. 165 out of them were divided into 11 groups of 15 teeth. One group was acid etching and the rest groups were irradiated with Nd:YAG laser by four different energy levels(100mj 10pps, 100mj 20pps, 150mj 20pps, 200mj 20pps) and with Er:YAG laser by six different energy levels(60mj 5pps, 60mj 10pps, 100mj 10pps. 200mj 10pps, 200mj l5pps, 400mj 10pps). Shear bond strength was tested with Instron after 24 hours, one week, and three weeks. Twenty-four out of 189 teeth were divided into twelve groups untreated control, acid etching, and ten laser irradiation subgroups. And the ultrastructural enamel surfaces of each group were observed with scanning electron microscope. The results were as follows; 1. The means and the standard deviations of shear bond strength of Nd:YAG and Er:YAU laser irradiation by different energy levels were obtained. 2. Shear bond strengths of Er:YAG laser irradiation groups were higher than those of Nd:YAG laser irradiation groups at the identical energy level. 3. Maximum bond strengths was achieved at the energy of I50mj, 20pps in Nd:YAG laser irradiation groups or 60mj, 10pps in Er:YAG laser irradiation groups. 4. It was acceptible for direct bonding to irradiate lb0mj 20pps with Nd:YAG laser or to irradiate 60mj 10pps with Er:YAG laser considering the results of shear bond strength tests and SEM obsesvation.