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The study aims to develop a new control chart model suitable for monitoring the process quality of multistage manufacturing systems. Considering both the auto-correlated process outputs and the correlation occurring between neighboring stages in a multistage manufacturing system, we first propose a new multiple linear regression model to describe their relationship. Then, the multistage residual EWMA and CUSUM control charts are used to monitor the overall process quality of multistage systems. Moreover, an overall run length (ORL) concept is adopted to compare the detecting performance for various multistage residual control charts. Finally, a numerical example with oxide thickness measurements of a three-stage silicon wafer manufacturing process is given to demonstrate the usefulness of our proposed multistage residual control charts in the Phase II monitoring. A computerized algorithm can also be written based on our proposed scheme for the multistage residual EWMA/CUSUM control charts and it may be further converted to an expert and intelligent system. Hopefully, the results of this study can provide a better alternative for detecting process change and serve as a useful guideline for quality practitioners when monitoring and controlling the process quality of multistage systems with auto-correlated data. [ABSTRACT FROM AUTHOR]

Measurement system analysis (MSA) plays an important role in helping organizations to improve their product quality. Usually, a gauge repeatability and reproducibility (GRR) study needs to be conducted prior to the process capability analysis for assessing the adequacy of gauge variation. In performing multivariate MSA for multivariate measurement systems, the existing multivariate precision-to-tolerance (P/T) ratio does not take the correlation coefficients among tolerances into account. Moreover, the optimal allocation of several parameters such as the number of quality characteristics ( v ), sample size of parts ( p ), number of operators ( o ) and replicate measurements ( r ) have not been considered in the multivariate GRR study either. As the total number of measurements ( n ) increase, the estimated total variation becomes more precise, but the related inspection time and costs will be increased as well. Striking the right balance between the precision of measurement system while still maintaining cost-effectiveness in determining the optimal allocation of opr parameters for correlated quality characteristics becomes an important issue in practical applications. In this paper, a revised precision-to-tolerance (P/T) ratio for multivariate MSA with correlated quality characteristics is proposed. The simulation results show that our revised P/T ratio outperforms the existing ones in terms of MSE and MAPE. We have also found that two parameters (number of parts p and a total number of measurements n ) significantly affect the expected length of confidence interval of P / T R . A reference table with the optimal allocation of por parameters is constructed accordingly if the inspection cost is limited. Finally, a numerical example with a step-by-step procedure for conducting a MGRR study is given to illustrate the appropriateness of our proposed P/T ratio. Hopefully, it can be served as a useful guideline for quality practitioners when performing a multivariate measurement system analysis in industries. [ABSTRACT FROM AUTHOR]

Highlights: [•] We propose three novel capability indices for multidimensional machining processes. [•] Consider the variances of machining results on different directions may not be equal. [•] The statistical properties of the point estimators for the new indices are derived. [•] The simulation results show that the new indices outperform the predecessors. [•] Two numerical examples further demonstrate the usefulness of our proposed indices. [ABSTRACT FROM AUTHOR]

3-Monochloropropane-1,2-diol (3-MCPD), 2,3-epoxy-1-propanol (glycidol), and their esters are well-known food contaminants mainly formed by the heat processing of certain refined oils and coexist in various kinds of foodstuffs. However, the combined health effect and the underlying mechanism of 3-MCPD and glycidol coexposure are not well-understood. In this study, we investigated the systemic toxicity effects and the nephrotoxicity mechanisms of 3-MCPD and glycidol coexposure with in vitro and in vivo models, and next-generation sequencing (NGS) analysis. It was found that 3-MCPD and glycidol coexposure for 28 days synergistically induced toxicity in the kidney, lung, testis, and heart in C57BL/6 mice. Kidney was the most sensitive organ to coexposure, and the coexposure had a synergistic effect on inflammation and cytotoxicity through activation of the NLRP3 inflammasome, and the induction of necroptosis, and autophagic cell death in NRK-52E cells. Moreover, the NGS results revealed the genes changes associated with nephrotoxicity, inflammation and with the broad toxicity effects induced by 3-MCPD or glycidol alone or in combination, which were consistent with the results of in vitro and in vivo models. In summary, we report for the first time of the comprehensive toxicity effects and the mechanisms caused by 3-MCPD and glycidol coexposure. ga1 • This is the first study to reveal the toxicity mechanisms of coexposure to food contaminants 3-MCPD and glycidol. • Coexposure conditions induced a more toxic response in the organs including kidney, lung, testis, and heart. • Synergistic nephrotoxicity was a significant effect after coexposure. • NLRP3 inflammasome activation, necroptosis, and autophagic cell death contributed to synergistic nephrotoxicity. • This study raised the awareness of the toxicity effects of 3-MCPD and glycidol coexposure. [ABSTRACT FROM AUTHOR]

Abstract: Background and purpose: To determine if dose and/or dose-volume parameters to anatomic swallowing structures are predictive of gastrostomy tube (PEG) dependence from chemotherapy-intensity modulated radiotherapy (IMRT) in locally advanced head and neck cancer (LAHNC). Methods and materials: A retrospective study was performed on 141 consecutive patients with LAHNC (squamous cell) treated with definitive chemoIMRT with weekly concurrent carboplatin and paclitaxel. Late dysphagia was assessed by length of PEG requirement. Analysis of IMRT dose was retrospectively performed for critical swallowing structures. Results: Approximately 62% of patients required PEG, the majority placed during treatment. Mean and median time for PEG was 7.7 and 4.4months respectively (range 1.4–43.8). Only IMRT dose to the inferior constrictor was significantly associated with length of PEG. Mean dose (of individual mean doses) was 47Gy for prolonged PEG use versus 41Gy for PEG ⩽12months. V40 to the inferior constrictor also correlated with PEG >12months (p =0.02) with a mean V40 of 48% versus 41% for PEG ⩽12months. Conclusions: IMRT dose to the inferior constrictor correlated with persistent dysphagia requiring prolonged PEG use. Maintaining mean inferior constrictor dose to ⩽41Gy and V40 to ⩽41% may help minimize gastrostomy tube dependence. [Copyright &y& Elsevier]