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Abstract: The microstructure of mechanically alloyed Mo–Si–B materials of different compositions has been studied by X-ray diffraction and FIB-tomography. Three different phases were found in all alloys: α-Mo solid solution, T2-phase (Mo5SiB2-type) and A15-phase (Mo3Si). The Mo–6Si–5B and Mo–9Si–8B (at%) alloys reveal a continuous morphology of the α-Mo phase. In Mo–9Si–8B the α-Mo phase is distributed more homogeneously compared to the Mo–6Si–5B alloy. In contrast, Mo–13Si–12B does not possess a continuous α-Mo phase. The consequences for the mechanical properties and oxidation resistance are discussed. [ABSTRACT FROM AUTHOR]

Abstract: Introduction: Liver tumors should be surgically treated whenever possible. In the case of bilobar disease or coexisting liver cirrhosis, surgical options are limited. Radiofrequency ablation (RFA) has been successfully used for irresectable liver tumors. The combination of hepatic resection and RFA extends the feasibility of open surgical procedures in patients with liver metastases and hepatocellular carcinoma (HCC). Patients and methods: RFA was performed with two different monopolar devices using ultrasound guidance. Intraoperative use of RFA for the treatment of liver metastases or HCC was limited to otherwise irresectable tumors during open surgical procedures including hepatic resections. Irresectability was considered if bilobar disease was treated, the functional hepatic reserve was impaired or appraised marginal for allowing further resection. Results: Ten patients with both liver metastases and HCC, and two patients with cholangiocellular carcinoma were treated. Complete initial tumor clearance was achieved in all patients. Two patients of the metastases group and five patients of the HCC group suffered from local recurrence after a median of 12 months (1–26) (local recurrence rate 32%). Five patients of the metastases group and six patients of the HCC group developed recurrent tumors in different areas of the ablation site after a median time of 4 months (2–18) (distant intrahepatic recurrence in 55%). Survival at 31 months was 36%. Conclusion: RFA extends the scope of surgery in some candidates with intraoperatively found irresectability. [Copyright &y& Elsevier]

Specimens of single crystal superalloy SC16 were creep-strained at 1223K along the [001] direction up to rupture using a creep stress of 150MPa. After creep strain, structural changes were monitored by X-ray diffraction measuring fundamental and superlattice reflections. Measurements were performed in the temperature range between room temperature and 1173K as a function of temperature and time. The data indicate two relaxation processes which are ascribed to thermally activated rearrangement of damage structures created during creep deformation. [Copyright &y& Elsevier]

Abstract: Aims: Liver resection represents a curative treatment approach in patients suffering from liver metastases from gastric cancer. However, its value in the treatment of these patients remains controversial. This study was conducted to evaluate the safety and effectiveness of liver resection in these conditions and to identify criteria for the selection of suitable patients. Methods: From January 1988 to December 2002, 24 patients underwent liver resection for metastatic gastric cancer. The outcome of these 24 patients was retrospectively reviewed using a prospective database. Patient, tumour and operative parameters were analyzed for their influence on long-term survival. Results: One patient died and four patients (17%) developed complications during the postoperative course. The overall one-, three- and five-year survival was 38%, 16% and 10%, respectively. After curative resection (n =17), the one-, three- and five-year survival rate was 53%, 22% and 15%, respectively, and patients with metachronous metastases restricted to the liver (n =5) had a one-, three- and five-year survival of 80%, 40% and 40%, respectively. In the univariate analysis, extrahepatic manifestation showed in tendency (p =0.069) and resection margins statistically significant (p =0.005) influence on survival. The multivariate analysis revealed only resection margins as an independent prognostic factor for survival. Conclusions: Long-term survival can be achieved by liver resection in well selected patients and may be considered in the multidisciplinary treatment approach of metastatic gastric cancer. Patients with metastatic disease restricted to the liver in whom a curative resection can be achieved seem to be most suitable for liver resection. [Copyright &y& Elsevier]

Abstract: Aims: Numerous patients suffer from recurrence after resection of liver metastases from colorectal cancer. Recurrence is frequently restricted to the liver and repeat liver resection may offer a curative option in these patients. This study was conducted to clarify safety and effectiveness of this treatment and to identify prognostic factors of a favourable outcome after repeat hepatectomy. Methods: Between January 1988 and March 2006 in our institution 811 patients underwent 841 liver resections for metastases from colorectal cancer. Among these, 94 patients underwent a repeat hepatectomy. Patients were identified from a prospective database and retrospectively reviewed. Results of different time periods were assessed and prognostic factors for a favourable outcome were determined. Results: The perioperative morbidity and mortality was 24% (23 of 94) and 3% (3 of 94), respectively. The one-, three-, five- and ten-year survival for all patients in this series was 89%, 55%, 38% and 23%, respectively. In the univariate analysis, pT-stage of the primary, diameter of the largest metastases, surgical radicality, period of resection and distribution of metastases showed statistically significant influence on survival. The multivariate analysis revealed only pT-stage of the primary tumour, surgical radicality and period of resection as independent prognostic factors. Conclusions: Repeat hepatectomy is a safe and effective treatment for recurrent liver metastases from colorectal cancer. Perioperative risk and long-term survival were similar when compared to the results obtained during the initial resection. Achieving a curative resection is the most relevant prognostic factor for a favourable prognosis after repeat liver resection. [Copyright &y& Elsevier]

Ex and in situ (⩽1300°C) small-angle neutron scattering (SANS) experiments on annealed layers of air-plasma sprayed La2Zr2O7 and SrZrO3 for thermal barrier coatings are presented. The deposits exposed at 1200°C up to 100h showed a stable microstructure of large pores. Medium-size (≈10–50nm) intragranular pores sinter during the exposure. The in situ SANS revealed that this process starts at 1000°C. In contrast to La2Zr2O7, the creation of nanopores starting at 900°C was detected in the SrZrO3 layer. These nanopores began to disappear at 1100°C. [Copyright &y& Elsevier]

The domain orientations and lamellar interfaces play a key role in the mechanical properties of TiAl-based alloys. All six domain orientations in the lamellar structure of a modern (α2+γ) two-phase alloy were therefore measured by means of convergent-beam electron diffraction. The transformation matrices necessary for indexing crystallographically differently oriented γ lamellae were systematically calculated. Based on these calculated matrices, the interface types between neighboring γ laths could be determined unambiguously. The frequency of different interface types was measured systematically and compared with the frequency distribution in binary TiAl alloys. [Copyright &y& Elsevier]

The domain orientations and lamellar interfaces play a critical role in the mechanical properties of TiAl based alloys. An umambiguous experimental determination of all six domain orientation in lamellar structure and the interfaces between neighboring γ laths in a (α2+γ) two-phase TiAl alloy containing Mn and Nb were analyzed by means of convergent-beam electron diffraction. The frequency of different interface types are reported. [Copyright &y& Elsevier]

Abstract: The abdominal aorta and the renal, mesenteric, and splenic arteries are frequently affected with arterial wall calcification upon increasing age; the hepatic artery is far less often found to be calcified. We report the case of a liver transplant recipient who presented with a calcified hepatic artery in the liver graft 13 years after transplantation for primary sclerosing cholangitis. Although the etiology of hepatic artery calcification was unknown, underlying causes for calcification may include chronic hemodialysis for renal insufficiency and subsequent secondary hyperparathyroidism, as well as a calcified aneurysms. However, it remained unclear whether hepatic artery calcification had to be considered an epiphenomenon or an original pathology of the liver. It thus seems unlikely that hepatic artery calcification as a single finding is to be considered a serious pathologic entity, even for a liver graft. [Copyright &y& Elsevier]

The crystallization behavior of amorphous Al 86 Ni 6 Y 4.5 La 1.5 Co 2 splats was analyzed by differential scanning calorimetry (DSC) and X-ray diffraction (XRD). Rietveld refinement was used to analyze the preferred orientation of fcc aluminum nanocrystals in the residual amorphous matrix after annealing. Fiber textures in [200] and [220] directions were found after heating to 360 °C. The influence of cold rolling on the preferred crystal orientation was studied as a function of the thickness reduction of the specimen. It was found that cold rolling significantly increases the (220) texture, while the (200) texture remains unchanged. Based on the experimental results the formation of (220) and (200) texture during the crystallization of the amorphous splats was ascribed to two different processes, internal stresses induced during splat formation or cold-rolling. [ABSTRACT FROM AUTHOR]