On the Effect of Nb on the Microstructure and Properties of Next Generation Polycrystalline Powder Metallurgy Ni-Based Superalloys

Abstract The effect of Nb on the properties and microstructure of two novel powder metallurgy (P/M) Ni-based superalloys was evaluated, and the results critically compared with the Rolls-Royce alloy RR1000. The Nb-containing alloy was found to exhibit improved tensile and creep properties as well as superior oxidation resistance compared with both RR1000 and the Nb-free variant tested. The beneficial effect of Nb on the tensile and creep properties was due to the microstructures obtained following the post-solution heat treatments, which led to a higher γ′ volume fraction and a finer tertiary γ′ distribution. In addition, an increase in the anti-phase-boundary energy of the γ′ phase is also expected with the addition of Nb, further contributing to the strength of the material. However, these modifications in the γ′ distribution detrimentally affect the dwell fatigue crack-growth behavior of the material, although this behavior can be improved through modified heat treatments. The oxidation resistance of the Nb-containing alloy was also enhanced as Nb is believed to accelerate the formation of a defect-free Cr2O3 scale. Overall, both developmental alloys, with and without the addition of Nb, were found to exhibit superior properties than RR1000.This work was supported by the Rolls-Royce/EPSRC Strategic Partnership under EP/H022309/1, EP/H500375/1 and EP/ M005607/1

Evaluating the Use of IT by the Third Party Logistics in South East Asia to Achieve Competitive Advantage and its Future Trend

As the number of using 3PL providers are increasing rapidly in recent years, 3PL providers play a major role in the logistics industry. Due to customers demands are raising and changing, it has facilitated 3PL providers to invest IT systems that could meet customer requirements and create competitive advantage. The use of IT systems could assist 3PL providers to achieve supply chain visibility and enhance supply chain collaboration with business partners. In this paper, it is mainly focus on the Europe and Far East 3PL providers in terms of current and future IT systems, IT motivators and barriers, as well as the future supply chain demands that address by IT systems. The common IT system that implemented in both regions is information technology, which is mainly used to collaborate and share information with supply chain partners. Some of the common motivations and barriers were existed and 3PL providers need to be understood. Given the future demands of IT implementation and supply chain collaboration, IT systems such as RFID and integration systems would be strongly focus in the future. The suggestion about the advanced integration system such as business process management (BPM) could be the next key IT systems in the future logistics industry

Antisense telomerase induced cell growth inhibition, cell cycle arrest and telomerase activity down-regulation in gastric and colon cancer cells

Anticancer Research231 A465-469ANTR

Prediction of differential creatinine clearance in chronically obstructed kidneys by non-contrast helical computerized tomography

PURPOSE: We investigate the use of non-contrast helical computerized tomography (NCHCT) in the measurement of differential renal parenchymal volume as a surrogate for differential creatinine clearance (CrCl) for unilateral chronically obstructed kidney. MATERIALS AND METHODS: Patients with unilateral chronically obstructed kidneys with normal contralateral kidneys were enrolled. Ultrasonography (USG) of the kidneys was first done with the cortical thickness of the site with the most renal substance in the upper pole, mid-kidney, and lower pole of both kidneys were measured, and the mean cortical thickness of each kidney was calculated. NCHCT was subsequently performed for each patient. The CT images were individually reviewed with the area of renal parenchyma measured for each kidney. Then the volume of the slices was summated to give the renal parenchymal volume of both the obstructed and normal kidneys. Finally, a percutaneous nephrostomy (PCN) was inserted to the obstructed kidney, and CrCl of both the obstructed kidney (PCN urine) and the normal side (voided urine) were measured two 2 after the relief of obstruction. RESULTS: From March 1999 to February 2001, thirty patients were enrolled into the study. Ninety percent of them had ureteral calculi. The differential CrCl of the obstructed kidney (%CrCl) was defined as the percentage of CrCl of the obstructed kidney as of the total CrCl, measured 2 weeks after relief of obstruction. The differential renal parenchymal volume of the obstructed kidney (%CTvol) was the percentage of renal parenchymal volume as of the total parenchymal volume. The differential USG cortical thickness of the obstructed kidney (%USGcort) was the percentage of mean cortical thickness as of the total mean cortical thickness. The Pearson's correlation coefficient (r) between %CTvol and %CrCl and that between %USGcort and %CrCl were 0.756 and 0.543 respectively. The regression line was %CrCl = (1.00) x %CTvol - 14.27. The %CTvol overestimated the differential creatinine clearance by about 14%, but the correlation is good. CONCLUSION: The differential renal parenchymal volume measured by NCHCT provided a reasonable prediction of differential creatinine clearance in chronically obstructed kidneys

Cloning of rat telomerase catalytic subunit functional domains, reconstitution of telomerase activity and enzymatic profile of pig and chicken tissues

10.1016/S0024-3205(03)00670-2Life Sciences73212749-2760LIFS

Prediction of differential creatinine clearance in chronically obstructed kidneys by non-contrast helical computerized tomography

PURPOSE: We investigate the use of non-contrast helical computerized tomography (NCHCT) in the measurement of differential renal parenchymal volume as a surrogate for differential creatinine clearance (CrCl) for unilateral chronically obstructed kidney. MATERIALS AND METHODS: Patients with unilateral chronically obstructed kidneys with normal contralateral kidneys were enrolled. Ultrasonography (USG) of the kidneys was first done with the cortical thickness of the site with the most renal substance in the upper pole, mid-kidney, and lower pole of both kidneys were measured, and the mean cortical thickness of each kidney was calculated. NCHCT was subsequently performed for each patient. The CT images were individually reviewed with the area of renal parenchyma measured for each kidney. Then the volume of the slices was summated to give the renal parenchymal volume of both the obstructed and normal kidneys. Finally, a percutaneous nephrostomy (PCN) was inserted to the obstructed kidney, and CrCl of both the obstructed kidney (PCN urine) and the normal side (voided urine) were measured two 2 after the relief of obstruction. RESULTS: From March 1999 to February 2001, thirty patients were enrolled into the study. Ninety percent of them had ureteral calculi. The differential CrCl of the obstructed kidney (%CrCl) was defined as the percentage of CrCl of the obstructed kidney as of the total CrCl, measured 2 weeks after relief of obstruction. The differential renal parenchymal volume of the obstructed kidney (%CTvol) was the percentage of renal parenchymal volume as of the total parenchymal volume. The differential USG cortical thickness of the obstructed kidney (%USGcort) was the percentage of mean cortical thickness as of the total mean cortical thickness. The Pearson's correlation coefficient (r) between %CTvol and %CrCl and that between %USGcort and %CrCl were 0.756 and 0.543 respectively. The regression line was %CrCl = (1.00) x %CTvol - 14.27. The %CTvol overestimated the differential creatinine clearance by about 14%, but the correlation is good. CONCLUSION: The differential renal parenchymal volume measured by NCHCT provided a reasonable prediction of differential creatinine clearance in chronically obstructed kidneys

Radiofrequency Ablation for 110 Malignant Liver Tumours: Preliminary Results on Percutaneous and Surgical Approaches

Radiofrequency ablation (RFA) has been widely applied for the treatment of hepatocellular carcinoma and liver metastases. The reported mortality and morbidity rates are low. The aim of this study is to evaluate the safety and efficacy of RFA, and compare the results performed percutaneously versus surgically. Patients and Methods: From 2003 to 2006, 79 patients with hepatic malignancies (59 hepatocellular carcinoma, 20 liver metastases) with a total of 110 lesions underwent RFA in our centre. Post-ablation assessment by CT scan was performed in all patients at 1-, 3- and 6-month intervals. Post-procedural complications, recurrence and survival were analysed. Results: The patients' mean age was 60.0 years. In 46.8% of cases, we used a percutaneous approach; in 53.2% of cases, a surgical approach (8.9% laparoscopic; 44.3% open) was used if percutaneous approach was not feasible. The mean tumour size was 2.4 cm. Within the surgical group, 69% of patients received concomitant operative procedures such as cholecystectomy and hepatectomy. No treatment-related mortality was observed. Immediate complications occurred in five patients (6.3%), including gastric serosal burn (n = 1), ground pad superficial skin burn (n = 1), intra-abdominal bleeding (n = 2) and pleural effusion (n = 1). All patients except one attended subsequent follow-up, with a mean period of 16 months. Ablation was considered complete in 82.3% of patients (percutaneous approach 81.1%, surgical approach 83.3%, p = 0.72). Intrahepatic recurrence was observed in 52.3%, the majority of them located away from the RFA site. Extrahepatic recurrences were observed in 16.9% (percutaneous approach 16.7%, surgical approach 17.1%, p = 0.76). The overall one- and two-year survival rate was 93.7% and 74.4% respectively, and no statistically significant difference was observed between the two approaches. Conclusion: RFA is a safe and effective procedure for treating patients with malignant liver tumours. No difference in short term outcomes was observed between percutaneous and surgical approaches. A more prolonged follow-up study is required to assess longer-term outcomes