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In the present paper, vibration signals recorded during a turning process are used for tool wear estimation. During the cutting process, tool acceleration signals are recorded by use of an accelerometer installed on tool holder, for different wear values. Since the measured acceleration signals have time dependent variance and are non-stationary, time series with time dependent coefficients were used for modelling them and extraction of wear sensitive features. The extracted wear sensitive features are residual variance of different signals and are used as distance between the signals associated with worn tools and the baseline model. A correlation was found based on analysis of distance between worn tools' acceleration signals in different cutting directions and the baseline signal. Using this correlation, a criterion was obtained for detection of critical wear stage. Such that the distance curves for feed and main cutting directions possess a minimum in the vicinity of critical wear level. Investigation of results revealed that the curves obtained through this method are more accurate than those obtained from stationary modelling method. The results obtained here can be used in online real-time algorithms of tool wear estimation. [ABSTRACT FROM AUTHOR]

Background: Matrix metalloproteinase-9 (MMP-9) has been reported as a new marker gene for several cancers. With respect to the significance function of this gene in diagnosis of cancers in the present study we compare the correlation between the plasma and serum MMP-9 levels and clinical features of breast cancer patients. Methods: In this case-control study, 120 breast cancer patients and 87 healthy controls were studded. MMP-9 level was quantitatively measured by zymography and specific kit. The results were compared with clinical features of patients. Finding: Plasma MMP-9 level was significantly elevated in breast cancer patients compared with the control subjects (P < 0.001). Also there was a correlation between the plasma MMP-9 level and lymph node metastasis (OR, 3.43; P = 0.019) and venous invasion (OR, 4.14; P = 0.033) of the patients. There was no correlation between the serum MMP-9 level and lymphatic metastasis or venous invasion. Conclusion: according to our findings the plasma MMP-9 level in comparison with the serum MMP- 9 level is a better determinant for early diagnosis, lymph node metastasis and venous invasion in patients with breast cancer. [ABSTRACT FROM AUTHOR]

Background and purpose: Juvenile delinquency is increasing in many countries including Iran. This study was designed to investigate the efficacy of forgiveness therapy in reducing aggression and enhancing forgiveness in adolescent boys in Tehran Correctional and Rehabilitation Centre. Material and Methods: This quasi-experimental study included pretest-posttest with control group. The research population consisted of all adolescent boys attending Tehran Correctional and Rehabilitation Centre in 2012. (almost 300 persons). Thirty accessible individuals were randomly selected and divided into experimental and control groups. The experimental group attended ten sessions of forgiveness therapy while the control group received no intervention. STAXI-2 and TRIM questionnaires were completed by subjects as pretest and posttest. Data was analysed performing MANOVA. Results: In this study forgiveness therapy based on Enright's process model, reduced aggression and promoted forgiveness in experimental group. Conclusion: Forgiveness therapy either alone or alongside other treatments could improve mental health, thereby reducing many unwanted consequences. [ABSTRACT FROM AUTHOR]