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Abstract This research designed a distribution-free mixed exponentially weighted moving average-moving average (EWMA-MA) control chart based on signed-rank statistic to effectively identify changes in the process location. The EWMA-MA charting statistic assigns more weight to information obtained from the recent $$w$$ w samples and exponentially decreasing weights to information accumulated from all other past samples. The run-length profile of the proposed chart is obtained by employing Monte Carlo simulation techniques. The effectiveness of the proposed chart is evaluated under symmetrical distributions using a variety of individual and overall performance measures. The analysis of the run-length profile indicates that the proposed chart performs better than the existing control charts discussed in the literature. Additionally, an application from a gas turbine is provided to demonstrate how the proposed chart can be used in practice.

This study aims to develop a nonparametric mixed exponentially weighted moving average-moving average (NPEWMA-MA) sign control chart for monitoring shifts in process location, particularly when the distribution of a critical quality characteristic is either unknown or non-normal. In literature, the variance expression of the mixed exponentially weighted moving average-moving average (EWMA-MA) statistic is calculated by allowing sequential moving averages to be independent, and thus the exclusion of covariance terms results in an inaccurate variance expression. Furthermore, the effectiveness of the EWMA-MA control chart deteriorates when the distribution of a critical quality characteristic deviates from normality. The proposed NPEWMA-MA sign control chart addresses these by utilizing the corrected variance of the EWMA-MA statistic and incorporating the nonparametric sign test into the EWMA-MA charting structure. The chart integrates the moving average (MA) statistic into the exponentially weighted moving average (EWMA) statistic. The EWMA-MA charting statistic assigns more weight to recent w samples, with weights for previous observations decling exponentially. Monte Carlo simulations assess the chart's performance using various run length (RL) characteristics such as average run length (ARL), standard deviation of run length (SDRL), and median run length (MRL). Additional measures for overall performance include the average extra quadratic loss (AEQL) and relative mean index (RMI). The proposed NPEWMA-MA sign control chart demonstrates superior performance compared to existing nonparametric control charts across different symmetrical and asymmetric distributions. It efficiently detects process shifts, as validated through both a simulated study and a real-life example from a combined cycle power plant.

1,4-alpha-D-glucan glucanohydrolase is among the most widely used commercial hydrolytic enzymes acting randomly on the glycosidic linkages of starch resulting in its saccharification and liquefaction. Its applicability in different industries can be improved by enhancing its stability and reusability. Therefore, in the present study attempts have been made to enhance the industrial applicability of 1,4-alpha-D-glucan glucanohydrolase from Bacillus subtilis KIBGE-HAR by adapting immobilization technology. The study developed mechanically stable, enzyme containing gel-frameworks using two support matrices including agar-agar, a natural polysaccharide and polyacrylamide gel, a synthetic organic polymer. These catalytic gel-scaffolds were compared with each other in terms of kinetics and stability of entrapped 1,4-α-D-glucan glucanohydrolase. In case of polyacrylamide gel, Km value for immobilized enzyme increased to 7.95 mg/mL, while immobilization in agar-agar resulted in decreased Km value i.e 0.277 mg/mL as compared to free enzyme. It was found that immobilized enzyme showed maximum activity at 70 °C in both the supports as compared to free enzyme having maximum activity at 60 °C. Immobilized 1,4-α-D-glucan glucanohydrolase exhibited no change in optimal pH 7.0 before and after entrapment in polyacrylamide gel and agar-agar. The enzyme containing gel-scaffold was found suitable for repeated batches of starch liquefaction in industrial processes. Agar-agar entrapped 1,4-α-D-glucanglucanohydrolase was capable to degrade starch up to seven repeated operational cycles whereas polyacrylamide entrapped enzyme conserved its activity up to sixth operational cycle.

Background: Bloodletting cupping therapy (Hijama) is a traditional alternative medicine practiced in different cultures. Claims about the therapeutic efficacy of Hijama in hypertension are contradictory. The aim of this project was to determine if Hijama therapy is beneficial in the treatment of patients with hypertension. Materials and Methods: In this retrospective study, 60 files for patients treated for hypertension, aged 40–60 years and whose systolic blood pressure (SBP) is at least 140mm Hg, were used. The data from 30 patient files were obtained from three licensed Hijama centers (study group), whereas data from the rest of 30 patient files were collected from a hospital (control group). The data from Hijama centers included age, date of Hijama therapy, and blood pressure measured before each Hijama session. Both diastolic blood pressure (DBP) and SBP data were obtained over 3-month period. Results: The results showed a significant reduction in SBP (P value < 0.01) over three sessions of wet cupping (from 149.2 to 130.8mm Hg), but this was not significant for DBP over three sessions (P = 0.074). The study also found that the mean SBP in the study group was 9.6mm Hg less than that in the control group (130.8 vs. 140.4mm Hg, P = 0.019), whereas there was no significant difference in DBP between the study group and the control group (87.0 vs. 86.0mm Hg, P = 0.75). Conclusions: Our study shows clear relationship between Hijama and the reduction and control of SBP in patients with hypertension. Therefore, Hijama can be used as an adjunct to conventional therapy, which may allow downtitration of given doses of antihypertensive drugs. The possible association of SBP reduction by Hijama and pain reduction needs an investigation.