Microstructural evolution in the thickness direction of an oxygen free copper processed by accumulative rollbonding (ARB) is investigated by electron back scatter diffraction (EBSD) measurement. For the ARB, two copper alloy sheets 1 mm thick, 30 mm wide and 300 mm long are first degreased and wire-brushed for sound bonding. The sheets are then stacked and roll-bonded by about 50% reduction rolling without lubrication at an ambient temperature. The bonded sheet is then cut to the two pieces of the same dimensions and the same procedure was repeated on the sheets up to eight cycles. The specimen after 1 cycle showed inhomogeneous microstructure in the thickness direction so that the grains near the surface were finer than those near the center. This inhomogeneity decreased with an increasing number of ARB cycles, and the grain sizes of the specimens after 3 cycles were almost identical. In addition, the aspect ratio of the grains decreased with an increasing number of ARB cycles due to the subdivision of the grains by shear deformation. The fraction of grains with high angle grain boundaries also increased with continuing process of the ARB so that it was higher than that of the low angle grain boundaries in specimens after 3 cycles. A discontinuous dynamic recrystallization occurred partially in specimens after 5 cycles.

The purpose of the current study was to determine the intra- and inter-rater reliability of muscle thickness (MT) measurement of the psoas major (PM) using ultrasonography (US) conducted at different inward pressures of approximately .5 ㎏, 1.0 ㎏, 1.5 ㎏, and 2.0 ㎏. Twelve healthy male subjects were recruited for the study. The thicknesses of both PMs of each subject were measured by two different examiners in a random manner to assess the intra- and inter-rater reliability. The measurement values were analyzed using the intra-class correlation coefficient (ICC) with a 95% confidence interval (CI). ICC (2,1) was used to determine the inter-rater reliability and ICC (3,1) was used to assess the intra-rater reliability of the MT measurement of the PM. The results indicated higher ICC values for intra-rater reliability compared to inter-rater reliability. In addition, the value for intra-rater reliability with .5 ㎏ inward pressure [ICC=.99 (95%CI=.98∼.99)] was higher compared to 1.0 ㎏, 1.5 ㎏, and 2.0 ㎏. Other inward pressures for intra- and inter-rater reliability in current study were also demonstrated to have excellent values (ICC=.94∼.99). These findings showed that maintaining consistent inward pressure is essential for maintaining reliability of the results when the MT of the PM is measured by different examiners in a clinical setting.

Ultrasonography (US) is a recent technique that has proven to be useful for assessing muscle thickness and guiding the rehabilitation decision-making of clinicians and researchers. The purpose of this study was to determine the inter-rater reliability of the US measurement of transversus abdominis (TrA), internal oblique (IO), and external oblique (EO) thicknesses for different probe locations and measurement techniques. Twenty healthy volunteers were recruited in this study. Muscle thicknesses of the transversus TrA, IO, and EO were measured three times in the hook-lying position. The three different probe locations were as follows: 1) Probe location 1 (PL1) was below the rib cage in direct vertical alignment with the anterior superior iliac spine (ASIS). 2) Probe location 2 (PL2) was halfway between the ASIS and the ribcage along the mid-axillary line. 3) Probe location 3 (PL3) was halfway between the iliac crest and the inferior angle of the rib cage, with adjustment to ensure the medial edge of the TrA. The two different techniques of thickness measurement from the captured images were as follows: 1) Muscle thickness was measured in the middle of the muscle belly, which was centered within the captured image (technique A; TA). 2) Muscle thickness was measured along a horizontal reference line located 2 cm apart from the medial edge of the TrA in the captured image (technique B; TB). The intraclass correlation coefficient (ICC [3,k]) was used to calculate the inter-rater reliability of the thickness measurement of TrA, IO and EO using the values from both the first and second examiner. In all three muscles, moderate to excellent reliability was found for all conditions (probe locations and measurement techniques) (ICC=.70~.97). In the PL1-TA condition, inter-rater reliability in the three muscle thicknesses was good to excellent (ICC=.85~.96). The reliability of all measurement conditions was excellent in IO (ICC=.95~.97). Therefore, the findings of this study suggest that TA can be applied to PL1 by clinicians and researchers in order to measure the thickness of abdominal muscles.

The reliability of the thickness measurement of the lumbar multifidus (LMD using real-time ultrasonography (US) was determined in only the superficial fiber of the lumbar multifidus (SM). However, previous studies have not examined the reliability of the deep fiber of the LM (DM). The purpose of this study was to determine the intrarater and the interrater reliability of the thickness measurements of DM using US. Eleven heathy males participated in the study. The thickness of the DM was measured with an US in the prone position. Reliability was examined using intraclass correlation coefficients (ICC), standard error of the measurement (SEM), and the Bland and Altman plot. ICC(3,1) was used to calculate the interrater reliability of the thickness measurement of DM using the values from both the first and second test sessions. Additionally, ICC(3,1) was used to calculate the intrarater reliability of the measurements over two days using the measurements obtained in test session 1 and lest session 2. The results of this study were as follows: 1) the ICC(3,1) value for interrater reliability was .94 in the first test session, and .93 in the second test session. 2) the ICC(3,1) values for intrarater reliability of the measurements over two days was .90 in both the first examiner and the second examiner. The interrater reliability and interrater reliability of the DM measurements, obtained via the US protocol used in this research was excellent. Therefore, we conclude that the thickness measurement of the DM obtaioned from the US protocol used in this research would be useful for clinician assessment of the thickness of the DM.

의료용 선형가속기 (linear accelerator)와 나선형 컴퓨터 단층 촬영 장치 (helical computed tomography scanner)의 결합 장치인 토모테라피는 세기 변조 방사선 치료 (intensity modulated radiation therapy(IMRT))의 큰 혁신을 이끌었다. 토모테라피 치료 과정에서, Megavoltage computed tomography (MVCT) 영상획득은 치료 환자의 정확한 자세 정렬을 위해 치료 전 또는 후에 이용된다. 그러나 이는 환자의 총 선량을 증가시키는 결과를 만들며, 본 연구는 이처럼 MVCT 영상 획득 시 증가되는 선량을 Cylindrical "Cheese" Phantom을 이용하여 측정, 비교하였다. 각각의 pitch별로 (1, 2, 3 mm) 동일한 개수의 slice (10 slice), 그리고 동일한 length (약 9 cm)를 scanning하여, 이때의 선량 (MVCT Scanning Dose)을 A1SL ion chamber를 이용하여 측정하였다. 측정 결과 동일한 Slice 개수 (각각의 pitch 당 10개)일 때, MVCT scanning dose의 평균값은 각각 (pitch 1, 2, 3mm) 2.24 cGy, 1.02 cGy, 0.81 cGy가 측정되었다. 동일한 length에서 MVCT scanning dose의 평균값은 각각 (pitch 1, 2, 3mm) 2.47 cGy, 1.28 cGy, 0.88 cGy가측정되었다. 이는 할당된 pitch와 scanning length가 MVCT scanning dose에 큰 영향을 미치는 가장 중요한 매개 변수임을 말하며, pitch는 MVCT scanning dose와 역비례 관계를 나타냈다. 때문에 적절한 pitch와 scanning length의 선택으로 치료 선량 외의 추가 선량을 최소로 줄여야 하겠다.