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The primary role of hard turning is to realize surfaces with high dimensional accuracy and high surface integrity to improve functional performances of the manufactured product. To this aim, the turning process parameters have to be carefully chosen. The present work deals with the correlation between hard turning parameters, surface and sub-surface characteristics, and corrosion behavior of the AISI 52100 bearing steel. Different cutting speeds and cooling conditions, specifically conventional flood and cryogenic cooling, were used for hard turning. Microstructural observations, residual stresses, nano-hardness, and surface finish measurements were carried out to assess the surface integrity modifications induced by machining. Then, potentiodynamic polarization curves were carried out, and the corroded surfaces were inspected. The obtained results showed that a remarkably improved corrosion resistance was obtained by using the lowest adopted cutting speed coupled with cryogenic cooling. Specifically, the former contributed to generate a wider nanostructure layer close to the machined surface, while the latter induced compressive residual stress state in correspondence of it. [ABSTRACT FROM AUTHOR]

Several radiotracers have been used for assessing cell death, whether by necrosis or apoptosis.99mTc glucarate, which has initially been reported to be concentrating/accumulating in myocardial infarction or zones of cerebral injury, has also shown some tumor-seeking properties in a few preliminary studies. Under International Atomic Energy Agency (IAEA)'s coordinated research program, we report here the standardization, quality control, and clinical evaluation (detection, evaluation of response, and comparison with 18F Fluorodeoxyglucose) of this tracer in well-characterized lung cancer and head neck malignancies in a single-arm prospective observational study. Forty-seven patients (29 inoperable lung carcinoma and 18 head and neck malignancies) were prospectively enrolled and underwent 99mTc glucarate imaging [whole body planar and single-photon emission computed tomography of the region of interest] 4-5 hours after injection of 20 mCi of the radiopharmaceutical. Excellent 99mTc glucarate concentration was noted in the target lesion in lung cancer and head and neck malignancies. The sensitivity was found to be better in lung cancer. Avid concentration of tracer was seen in the metastatic sites. During response evaluation, the glucarate concentration correlated well with the clinical and other radiological indings. 99mTc glucarate showed avid concentration of tracer in the tumor, suggesting it to be a potential tumor imaging agent which can be used for detection and assessment of therapeutic response in malignancy. [ABSTRACT FROM AUTHOR]