• Journal of the Korea Concrete Institute
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• v.23 no.5
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• pp.541-550
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• 2011

Many researches have been performed on concrete with fly ash and bottom ash. However researches on concrete with pond ash (PA) and its application to RC (Reinforced Concrete) structure are limitedly carried out. This paper presents an applicability of PA concrete in construction of real size structure. Referring to the previous study, 2 domestic PA samples with normal performance are selected and 2 replacement ratios (25% and 50%) to fine aggregate are considered for 5 PA concrete structures consisting of column, slab, and wall. In order to evaluate the property of fresh concrete, several tests including air content, slump, and setting time are performed. Using cored out samples from hardened PA concrete structure, tests for strength, resistance to carbonation and chloride penetration are carried out and compared with control samples. Additionally, tests for rebound hardness, drying shrinkage, and hydration heat are performed for PA concrete structure. The test results showed that PA concrete has reasonable strength and durability performances compared to those of normal concrete. Therefore, its potential application to RC structure is promising. The PA aggregate can be more actively used for RC structures with better quality control for content of fly ash, bottom ash, and unburned carbon.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.48 no.5
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• pp.249-258
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• 2022

The specific muscular structure of the tongue greatly affects margin shrinkage and tumor invasion, making the optimal surgical margin controversial. This study investigated surgical margin correlated prognosis of TSCC (tongue squamous cell carcinoma) according to margin location and its value, and the histopathologic factors which are suggestive of tumor invasion. And we would like to propose defining of the surgical margin for TSCC via prognosis according to location and margin values. We reviewed 45 patients diagnosed with TSCC who visited Seoul National University Dental Hospital (SNUDH) (Seoul, Republic of Korea) from 2010 to 2019, who were managed by a single surgical team. Patient clinical and pathological data of patients were retrospectively reviewed, and in 36 out of 45 patients, the pathologic parameters including the worst pattern of invasion (WPOI) and tumor budding were investigated via diagnostic histopathology slide reading. When standardized with as 0.25 cm anterior margins, as 0.35 cm deep margin, there was no significant difference in disease specific survival (DSS) or loco-regional recurrence-free survival (LRFS). Additionally, there was a non-significant difference in DSS and LRFS at the nearest margin of 0.35 cm (P_DSS=0.276, P_LRFS=0.162). Aggressive WPOI and high tumor budding showed lower survival and recurrence-free survival, and there were significant differences in close margin and involved margin frequencies. In TSCC, the value and location of the surgical margin did not have a significant relationship with prognosis, but WPOI and tumor budding suggesting the pattern of muscle invasion affected survival and recurrence-free survival. WPOI and tumor budding should be considered when setting an optimal surgical margin.