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Ball bearing is used to provide free rotation around a fixed axis. Various kinds of faults exist in the bearing such as inner race fault, outer race fault and ball race fault. One very effective method to diagnose the bearing fault is vibration signal analysis. Empirical mode decomposition (EMD) has been used for ball-bearing fault diagnosis in mechanical systems using vibration signal analysis. Classification of the ball-bearing fault has always been a challenging task. Various classification schemes such as Extreme learning machine (ELM), K-means Clustering, and Support vector machine (SVM), have been reported in the literature for ball-bearing fault classification. SVM is restricted by multiclass classification efficiency, and ELM is restricted by the longer training. In this paper, the entropy analysis of the wavelet coefficient obtained from the third level decomposition of the residue signal (obtained after subtracting the highest frequency component from the raw signal) has been done for ball-bearing fault classification. A comparative analysis of the wavelet coefficient based on entropy measurement has been presented here. High fault classification accuracy has been achieved using the proposed method for the detection of ball-bearing fault. Shannon entropy, Average Shannon entropy, and Renyi's entropy are parameters for the justification of the proposed approach. The result shows the best wavelet to be chosen among the available discrete wavelet based on various entropy measurements. [ABSTRACT FROM AUTHOR]

Background: Diabetes poses a global threat, leading to hospitalizations and premature death if not managed properly. It involves tumor necrosis factor-α (TNF-α), an inflammatory cytokine, which binds to TNF-α receptor-1, triggering sphingomyelinase, and ceramide production. Vitamin D acts as an anti-inflammatory agent, reducing inflammatory cytokines and proinflammatory cell growth, and benefiting diabetes mellitus (DM). Aims and Objectives: The primary objective was to compare serum Vitamin D and TNF-α levels in diabetics and nondiabetics. The secondary objective was to explore Vitamin D and TNF-α correlation in newly diagnosed type 2 diabetes. Materials and Methods: A case-control study involved 92 subjects in each group. Data included demographics, clinical assessments, glycemic parameters, Vitamin D, and TNF-α. Statistical analysis used student's t-test and Pearson correlation (P<0.05). Results: The cohort comprised 34 females (36.96%) and 58 males (63.04%). Cases had significantly higher glycemic levels: FBG (247.2±53.92 mg/dL vs. 91.45±16.64 mg/dL), postprandial plasma glucose (319.7±72.08 mg/dL vs. 111.3±21.76 mg/dL), and glycated hemoglobin (HbA1c) (10.39±2.41% vs. 5.43±0.48%). Mean serum Vitamin D in cases (22.63 ng/mL) was significantly lower than controls (58.15 ng/mL), and mean TNF-α in cases (5.01 pg/mL) was higher than controls (4.63 pg/mL, P<0.0001). HbA1c negatively correlated with serum Vitamin D (r=-0.7461) and positively with TNF-α (r=0.7831). Vitamin D correlated negatively with TNF-α (r=-0.6481). Conclusion: The study revealed lower serum Vitamin D and higher TNF-α levels in cases, with a significant inverse association. It also found an inverse link between Vitamin D and HbA1c and a strong positive correlation between HbA1c and TNF-α. Recognizing Vitamin D and TNF-α's diagnostic significance promises innovative strategies for managing type 2 DM. [ABSTRACT FROM AUTHOR]

Background: Vitiligo is a chronic, common disease of still unknown etiology characterized by circumscribed ivory or chalky white macules of different size and shape. The pathogenesis of vitiligo is complex and still not well understood. According to autocytotoxic hypothesis, oxidative stress has been suggested to be the initial pathogenic event in melanocyte degeneration. Objective: The present study was conducted with an objective to evaluate the role of oxidative stress and antioxidant status in the pathogenesis of vitiligo. Materials and Methods: A total of sixty (60) subjects (age group 14-50 years) of both sexes were enrolled in this study. Of 60, 30 were clinically diagnosed cases of vitiligo of all types and remaining 30 were normal healthy controls. The indicator of oxidative stress was determined by measuring serum level of MDA. The role of antioxidant was determined by measuring serum levels of SOD and Vitamin C. Results: The mean serum level of MDA was significantly increased in vitiligo patients compared to controls while the mean serum level of SOD was significantly decreased in patients of vitiligo than controls. Also, Vitamin C was decreased in vitiligo compared to controls but was insignificant. Conclusion: The result of the present study demonstrates imbalance between oxidant-antioxidant system and support the associations between oxidative stress and free radical-mediated damage in the pathogenesis of vitiligo. [ABSTRACT FROM AUTHOR]