관절 조영술을 이용한 족관절 염좌의 진단과 치료

김석중,옥인영,주인탁,송석환,하기용,김용훈,Kim, Seok-Jung,Ok, In-Young,Chu, In-Tak,Song, Seok-Whan,Ha, Kee-Yong,Kim, Yong-Hoon 대한족부족관절학회 2003 대한족부족관절학회지 Vol.7 No.2

Purpose: To evaluate the effectiveness of ankle arthrography in diagnosis and treatment of the ankle sprain. Materials and Methods: Arthrography was performed to eighteen patients who were diagnosed as ankle sprain clinically from September, 1990 to April, 2003. Splint immobilization for three days and return to daily life were for the eleven patients who showed normal limits of extension of joint and no dye leakage on arthrography, cast for 3 weeks and compression brace wearing were for 4 patients who showed anterior talofibular ligament tear on arthrography. 3 patients diagnosed as anterior talofibular and calcaneofibular ligament tears were treated with cast for 6 weeks and then brace for 3 weeks. Results: The range of motion of the injured joint was recovered normally at the time of 3 month of postoperative follow up examination. But two patients complained a mild pain after exercise but it did not affect ordinary activities. Eleven patients who were normal on arthrography returned to daily activities in a week. Conclusion: It is reasonable to determine the extent of ankle sprain and treatment method for it using arthrography.

하한지지력이 현장타설말뚝의 저항계수에 미치는 영향

김석중,박재현,김명모 한국지반공학회 2014 한국지반공학회논문집 Vol.30 No.11

Load and Resistance Factor Design (LRFD) is one of the limit state design methods, and has been used worldwide,especially in North America. Also, the study for LRFD has been actively conducted in Korea. However, the data forLRFD in Korea were not sufficient, so resistance factors suggested by AASTTO have been used for the design in Korea. But the resistance factors suggested by AASHTO represent the characteristics of bedrocks defined in the US, therefore,it is necessary to determine the resistance factors for designs in Korea, which can reflect the characteristics of bedrocksin Korea. Also, the calculated probabilities of failure from conventional reliability analyses which commonly uselog-normal distribution are not realistic because of the lower tail that can be extended to zero. Therefore, it is necessaryto calibrate the resistance factors considering the lower-bound resistance. Thus, this study calculates the resistance factorsusing thirteen sets of drilled shaft load test results, and then calibrates the resistance factors considering the lower-boundresistance corresponding to a target reliability index of 3.0. As a result, resistance factors from conventional reliabilityanalyses were determined in the range of 0.13-0.32 for the shaft resistance, and 0.19-0.29 for the base resistance,respectively. Also, the lower bounds of resistance were determined based on the Hoek-Brown failure criteria (2002)and GSI downgrading. Considering the lower-bound resistances, resistance factors increased by 0~8% for the shaft,and 0~13% for the base, respectively.

LRFD 설계를 위한 현장타설말뚝의 주면지지력 저항계수 산정

김석중,권오성,정성준,한진태,김명모 한국지반공학회 2010 한국지반공학회논문집 Vol.26 No.7

Load Resistance Factor Design method is used increasingly in geotechnical design world widely and resistance factors for drilled shafts are suggested by AASHTO. However, these resistance factors are determined for intact rock conditions; by comparison, most of bedrocks in Korea have weathered condition, so that applying the AASHTO resistance factors is not reasonable. Thus, this study suggests the proper resistance factors for design of drilled shaft in Korea. The 22 cases of pile load test data from 8 sites were chosen and reliability-based approach is used to analyze the data. Reliability analysis was performed by First Order Second Moment Method (FOSM) applying 4 bearing capacity equations. As a result, when the Factor of Safety (FOS) was selected as 3.0, the target reliability indexes () were evaluated as 2.01∼2.30. Resistance factors and load factors are determined from optimization based on above results. The resistance factors ranged between 0.48 and 0.56 and load factors for dead load and live load are evaluated as approximately 1.25 and 1.75 respectively. However, when the target reliabilities are considered as 3.0, the resistance factors are evaluated as approximately 50% of the results when the target reliability index was 2.0.

구조용 용접철망을 사용한 일방향 슬래브의 휨 거동에 관한 실험적 연구

김석중,정헌수,양지수,윤영호,허갑수 대한건축학회 1993 대한건축학회 학술발표대회 논문집 - 계획계/구조계 Vol.13 No.2

2-Nitropropane의 독성에 대한 멜라토닌의 억제 효과

김석중,Kim, Seok-Jung 한국식품연구원 1998 食品技術 Vol.11 No.4

간 독성 물질인 2-Nitropropane (2-NP)을 쥐의 복강내로 주사한 후에 조직에서의 지질산화(lipid peroxidation (LPO), malondialdehyde 와 4-hydroxyalkenal의 생산량)와 간 독성의 지표로서 혈청내의 soritol dehydrogenase(SDH) 활성을 측정하였다. 수많은 독성 물질에 대하여 방어효과를 보이는 멜라토닌(melatonin)을 2-NP 투여 30분전에 주사하여 2-NP에 대한 방어효과를 조사하였다. 2-NP 투여시에 LPO와 SDH 활성은 시간 (0, 4, 8, 24h) 및 2-NP의 농도 (0, 1, 2, 4mmol/kg)에 따라 증가하였고, 4mmol/kg의 2-NP을 투여한 24시간 후에는 간 (P<0.001), 폐 (P<0.05), 신장(P<0.001)에서 LPO가 유의적으로, 혈청에서의 SDH 활성은 470배 증가하였다. 멜라토닌을 농도에 따라 투여시(2.5, 5, 10 mg/kg) 간, 폐 신장에서 LPO가 간에 대하 발암성 물질인 2-NP가 지질산화도 유도 할 수 있으며, 약리적인 수준의 멜라토닌이 2-NP의 독성을 감소시킬 수 있음을 나타낸다.

경골 외과 골절에서 외측 반월상 연골 손상의 위험군

김석중,서정태,김정만,선두훈,장정호 대한골절학회 1999 대한골절학회지 Vol.12 No.3

Purpese: Untreated meniscus injuries accompanied with fractures of lateral tibial condyle may cause prolonged pain and post-traumatic arthritis. Lateral displacement of fractured fragment of lateral tibial condyle was found to be related to the incidence of lateral meniscus tear. We established the risk groups for lateral meniscus injuries on the basis of the degree of the lateral displacement of lateral tibial condyle. Materials and Methods: Risk groups for lateral meniscus injury in fractures of lateral tibial condyle were evaluated in 39 knees, retrospectively, using plain roentgenograms and arthroscopic findings. On the knee anteroposterior radiography, displacement of lateral tibia condyle were classified into three groups according to the probability of lateral meniscus injury: high risk group for above 8mm of lateral displacement; moderate risk group for 4- 8mm; low risk group for less than 4mm. Results: High risk group has ten meniscus injuries among 13 knees (76.9%) and moderate risk group had the seven meniscus injuries of 18 knees (38.9%). Low risk group of eight knees had no meniscus injury (0%). These different incidences among groups were statistically significant (p$lt;0.05). Conclusions: The authors suggest that the incidence of lateral meniscus injury was related to the degree of lateral displacement of lateral tibial condyle, and our definition of risk groups are useful for prediction of lateral meniscus injury in fracture of lateral tibial condyle.

발아기간에 따른 유채종자의 일반성분 조성, 항산화능 및 멜라토닌 함량의 변화

김석중 한국식품저장유통학회 2016 한국식품저장유통학회지 Vol.23 No.6

The changes of approximate composition, antioxidant activity and melatonin content in rapeseed were monitored during 10 days germination to choose the optimum sprouts with beneficial functionalities. The moisture content of seeds increased from 3.23% to 17.50% during 10 days germination period, while ash content was similar (4.03~4.91%). The fat content was reduced from 38.18% to 22.65%, however, protein content increased from 21.43% to 26.72%. The carbohydrate content increased from 32.71% to 35.84% at 8th day. The reducing sugar and fiber contents reached 10.47% and 15.12% at 6th day from 4.04% and 12.82%, respectively. Eighth day sprouts contained highest level of polyphenol (gallic acid equivalent, 19.2 g/kg). Germination increased antioxidant activities (trolox equivalent, mmol/kg) of seeds with slight difference depending on assay. That is, antioxidant activity was highest at 6th day in DPPH radical scavenging (55.9), 10th day both in ABTS radical scavenging (71.6) and Fe(III) reducing (125.3), and 4th day in peroxy radical scavenging (116.7) assay. Melatonin content of seeds (0.85 μg/kg) also increased and reached up to 14.93 μg/kg at 6th day. In conclusion, germination more than 4 days raised antioxidant activity of seeds highly, and 6th day sprouts had additional benefit in terms of melatonin, reducing sugar and crude fiber contents.

편집후기

김석중 한국지반공학회 2023 지반 : 한국지반공학회지 Vol.39 No.5

홀로그래피 간섭계를 이용한 복합적층판의 결함측정

김석중,김재형,박현철 대한기계학회 1994 대한기계학회논문집 Vol.18 No.12

Mode shapes and natural frequencies of vibrating laminated composite plates are taken using real-time and time-average holographic interferometry. Debonds and delamination in the laminated plates are measured nondestructively. During holographic testing of composite plates, it has been found that the conditions for the local resonance in debonds are strongly dependent on the frequency of excitation. A membrane resonance model was proposed to describe this behavior. Relations between characteristic length according to the size, shape of debonds and membrane resonance frequency are presented. Several experiments were performed to verify the membrane resonance model. The agreements between the predicted excitation frequency and the observed resonance frequency are good. The experimental results show that higher stresses and strains due to local resonance lead to the debond detection.

Hydroxyl radical에 의해 유도된 단백질, 지질의 산화적 손상에 대한 멜라토닌, glutathione, $\alpha$-tocopherol의 방어효과

김석중,Kim, Seok-Jung 한국식품연구원 1998 食品技術 Vol.11 No.4

Ascorbate-$Fe^3+$-EDTA에 의해 생성된 hydroxyl radical (HO.)을 이용하여 단백질과 지질의 산화적 손상을 유도하였으며, 이 손상에 대한 멜라토닌(melatonin), glutathione, $\alpha$-tocopherol의 방어효과를 분석하였다. 단백질로는 bovine serum albumin (BSA), 지질로는 phosphatidyl-choline (PC) liposome을 이용하였다. 그리고 BSA와 PC liposome의 혼합계에서도 각 항산화제의 효능을 분석하였다. 단백질의 산화적 손상은 carbonyl기의 생성 및 단백질 절단을, 지질산화는 lipid peroxidation (LPO, malondialdehyde 와 4-hydroxyalkenal) 분석을 통하여 조사하였다. 단백질의 산화는 멜라토닌과 glutathione이, 지질산화는 멜라토닌과 $\alpha$-tocopherol이 효과적으로 억제하였다. 그러나 glutathione은 지질, $\alpha$-tocopherol은 단백질의 산화를 억제하지 못하였다. BSA와 PC liposome이 동시에 존재하는 혼합물에서는 수용성과 지용성 특성을 모두 지닌 멜라토닌은 단백질, 지질 모두에 대해 산화방지효과가 있으나 수용성인 glutathione은 단백질에, 지용성인 $\alpha$-tocopherol은 지질에만 주로 효과가 있는 것으로 조사되었다.