We reviewed surgically treated patients with intrahepatic cholangiocarcinoma to evaluate the clinical and pathologic features of intrahepatic cholangiocarcinoma that may affect long-term survival in Korean patients with the disease. Between 1990 and 1997, 28 patients with intrahepatic cholangiocarcinoma underwent laparotomy. Resection was performed in 25 patients, and wedge resection alone in 3 patients. The liver resections consisted of right lobectomy in 5 patients, right trisegmentectomy in 1, left lobectomy in 7, extended left lobectomy in 3, hepatopancreatoduodenectomy in 2, and segmentectomy in 7. Curative resection was performed in 15 patients. Histological sections of all resected specimens were immunohistochemically stained with p53 and Ki-67 monoclonal antibodies to assess the biological behavior of the tumor cells. Cumulative survival rate and clinicopathological factors that may influence the prognosis, including biological markers (p53, Ki-67), were analyzed statistically. Patients who underwent curative resection survived significantly longer than patients who underwent noncurative resection. The median survival time of the patients who underwent curative resection was 24 months (mean, 34 +/- 8 months), with 1-, 2-, and 3-year survival rates of 66.6%, 44.4%, and 35.6%, respectively. The median survival time of the patients who underwent noncurative resection was 3 months (mean, 8 +/- 3 months), with 1- and 2-year survival rates of 26.7% and 13. 4%, respectively. Univariate analysis showed that positive regional lymph nodes correlated significantly with poor outcome (P = 0.004) and that curative resection significantly correlated with better prognosis (P = 0.001). Age, sex, tumor size, degree of cell differentiation, gross type of tumor, and p53 and Ki-67 labeling index were not significantly correlated with outcome. Our findings support the concept that aggressive liver resection, along with regional lymph node dissection, be recommended for long-term survival. The validity of molecular biologic tumor markers (p53, Ki-67) as prognostic factors has not yet been clearly demonstrated.

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This study addresses the application of compressed wood (CW) made of Japanese cedar, as a substitute for high-density hardwood, to shear dowel. A double woodto-wood shear test was performed to evaluate the mechanical shear properties of CW perpendicular to the grain, and the results were compared with those of several types of dowel material. CW with its annual ring radial to loading direction (08) had a unique double shear performance characteristic, and showed good properties as a dowel material by virtue of its strength and rich ductility. In contrast, CW with its annual ring tangential to loading direction (908) and maple exhibited brittle failure. While thickness of the base member was varied, the ductility of the joint became stable for diameter over 36 mm and 24 mm thickness for the main and side members, respectively. When the density of the base member increased, its stiffness, yield load, and maximum load exhibited proportional improvement with different inclinations; however, in the case of a maple dowel, the increases were small. When the density of the base member was increased, the ultimate load had positive linear tendency, whereas plastic modulus decreased. Consequently, almost constant energy absorption was observed in spite of the increased density. The optimum load-carrying capacity and ductility of a compressed wooden dowel joint could be designed by introducing an appropriate base member.

This study uses partially threaded self-tapping screws to enhance the mechanical properties of damaged and undamaged dowel-type timber connections. The damaged connections have a 1.5mm wide artificial crack across the middle row of the fasteners. Test results showed that screw reinforcement can restore the rotation capacity of damaged connections. The rotational capacity of reinforced connections without cracks is 45.6% higher than unreinforced connections while the improvement on moment-resisting capacity is slight. Digital image correlation (DIC) was used to detect the movement of the connections and validated that the fasteners rotate around the centre of rotation in reinforced connections. Screw reinforcement also demonstrated the ability to control crack propagation, with the reinforced groups showed a reduction of crack length by at least 37% when compared to the unreinforced groups. A calculation method is proposed to calculate the characteristic moment-resisting capacity of damaged and undamaged screw reinforced connections. The calculated values are proven to be conservative when compared with the characteristic value based on the experimental results. Highlights  Self-tapping screws restored the rotational capacity of connections with cracks  Partially threaded screws showed a trend to effectively control crack propagation  A theoretical prediction method is demonstrated

The material properties of compressed wood were investigated according to the compression ratio, considering its use as mechanical fasteners. Compressed wood made of Japanese cedar in various compression ratios was provided for material tests such as tension, compression, bending, shearing and bearing. The relationship between stiffness or strength and density were investigated. In order to clarify the influence of the improvement of material properties, test results were standardized by using density and material properties of non-compressed wood. As a result, it was made clear that tension and compression properties parallel to the grain and bending properties improved in proportion to the increment of density regardless of the deformation of the cell wall. Shear elastic modulus and strength on the LT plane increased almost in proportion to the density, but no such improvement was observed in those on the LR plane. Shear elastic modulus on the LT plane and strength on the LR plane showed rather higher values than the ideal relationship with density, and elastic modulus on the LR plane and strength on the LT plane showed rather lower values at low density and then became higher than the ideal relationship. Those tendencies were qualitatively explained by a model of cell wall deformation. MOE and strength on bearing in the T direction increased following a power function with index of 2 and 1.8, respectively. On the other hand, their changes in the R direction were relatively small until the cells of early wood fully turned into compressed cells, and then they increased very drastically. This tendency was very similar to the stress-strain relationship in R-compression of normal softwood, and was explained well by the honeycomb cell model of the deformed compressed cell.