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An accuracy synthesis approach for a 2UPS & UPR & UP parallel robot is proposed. Based on the nominal kinematic equations, an error mapping model of the robot is established using the perturbation method, and the compensable and uncompensable geometric error sources are sorted out. The standard deviation relationship between the uncompensable error sources and the terminal attitude errors is established to reveal the standard deviation distribution of the terminal attitude error in the workspace. A sensitivity analysis of the uncompensable error sources is carried out to determine the influence of each uncompensable geometric error source on the terminal accuracy. According to the 3σ principle, the sensitivity index is taken as the allocation coefficient, and the values of the uncompensable error sources under the given terminal accuracy are obtained through the accuracy synthesis. The proposed approach can provide a theoretical basis for the manufacturing of the robot, and the effectiveness of the proposed method is verified by simulation.

Vibration signal diagnosis and analysis plays an important role in the industrial machinery since it enhances the machinery performance under supervision. The information regarding the future condition is given by vibration diagnosis techniques which is growing interest for the scientific and industrial communities. Information for failure diagnostic and prediction are provided by the motor vibration through signal processing. The development of mechanical systems fault prognosis and in the last decades, research is done at a very rapid rate. The examination of vibration signal monitoring is done in this paper with the aid of Cyber-Physical Systems (CPS) and Cloud Technology (CT). The machines maintenance strategies are implemented by using the data collected from machines which are based on the fault prognosis. The cloud computing platform is presented in this paper which is having three layers and the unlabelled data is received to generate an interpreted online decision. Feature extraction of the vibration signal is obtained in terms of range, mean value, root mean square value, and standard deviation and crest values. The performance of the model is evaluated by utilizing the classical statistical metrics such as RMSE Mean Absolute Error (MAE) and Mean Absolute Percentage Error (MAPE) of the vibration signal. It is obtained that the proposed technique is 25% and 90% better than the Adaptive Neurofuzzy Inference System and the Single Modeling System respectively in terms of RMSE. The performance in terms of MAPE, then the proposed technique outperforms the existing Adaptive Neurofuzzy Inference System and the Single Modeling System by 8 % and 60% respectively. The presented technique is better than the existing Adaptive Neurofuzzy Inference System and the Single Modeling techniques by average of 15% and 30 % respectively.

Stainless steel 441 was oxidized in water vapor containing atmospheres at 1,000 °C to study the contrary effects of water vapor on the oxidization process. The steel in 3.5 vol. % H2O containing atmosphere exhibited an relatively strong protective behavior. The reason was that the densification of the chromium oxide scale was promoted due to the sintering of the oxide grains via Cr-containing species vapor. But the oxidation of the steel in 11.5 ~ 15.6 vol. % H2O containing atmosphere followed a non-protective breakaway oxidation due to the breakage of the dense scale by “bubbles” and the formation of iron-rich oxides layer. Experimental result shows that the growth stress increased about 2 GPa during the first 70 ks in wet oxidizing atmosphere. The relatively slow increase of the oxides scale growth stress could be release in water vapor containing atmosphere.

In order to supply data to the signal processing study of spaceborne InSAR system,the interferometric signal simulation was studied.At first the geometric model,backscattering model and signal model needed by the simulation was analyzed.Using these models the simulation process was given.Then the relationship between facet number and correlation coefficient was analyzed.The analysis shows that by using right facet number the simulated signal can inter-fere and the correlation coefficient can near its theoretic value.Simulated results can validate this method.

Abstract Background An antibody with cross-reactivity can create unexpected side effects or false diagnostic reports if used for clinical purposes. ERCC1 is being explored as a predictive diagnostic biomarker for cisplatin-based chemotherapy. High ERCC1 expression is linked to drug resistance on cisplatin-based chemotherapy. 8F1 is one of the most commonly used monoclonal antibodies for evaluating ERCC1 expression levels in lung cancer patient tissues, but it has been noted that this antibody cross-reacts with an unknown protein. Results By using a high density protein microarray chip technology, we discovered that 8F1 not only reacts with its authentic target, ERCC1, but also cross-reacts with an unrelated nuclear membrane protein, PCYT1A. The cross-reactivity is due to a common epitope presented on these two unrelated proteins. Similar to the subcellular localization of ERCC1, IHC tests demonstrated that PCYT1A is localized mainly on nuclear membrane. In this study, we also discovered that the PCYT1A gene expression level is significantly higher than the ERCC1 gene expression level in a certain population of lung cancer patient tissue samples. To develop the best monoclonal antibody for ERCC1 IHC analysis, 18 monoclonal antibodies were generated and 6 of them were screened against our protein microarray chip. Two clones showed high mono-specificity on the protein microarray chip test and both worked for the IHC application. Conclusion In summary, the 8F1 clone is not suitable for ERCC1 IHC assay due to its cross-reactivity with PCYT1A protein. Two newly generated monoclonal antibodies, 4F9 and 2E12, demonstrated ultra-specificity against ERCC1 protein and superior performance for IHC analyses.

Introduction and Objectives: Hepatitis B surface antigen (HBsAg) clearance, indicating functional cure or resolved chronic hepatitis B (CHB), remains difficult to achieve via nucleos(t)ide analogue monotherapy. We investigated whether metformin add-on therapy could help achieve this goal in entecavir-treated patients with hepatitis B e antigen (HBeAg)-negative CHB., Patients and Methods: Patients with HBeAg-negative CHB who met eligibility criteria (entecavir treatment for > 12 months, HBsAg < 1000 IU/mL) were randomly assigned (1:1) to receive 24 weeks of either metformin (1000 mg, oral, once a day) or placebo (oral, once a day) add-on therapy. The group allocation was blinded for both patients and investigators. Efficacy and safety analyses were based on the intention-to-treat set. The primary outcome, serum HBsAg level (IU/mL) at weeks 24 and 36, was analysed using mixed models., Results: Sixty eligible patients were randomly assigned to the metformin (n = 29) and placebo (n = 31) groups. There was no substantial between-group difference in the HBsAg level at week 24 (adjusted mean difference 0.05, 95% confidence interval -0.04 to 0.13, p = 0.278) or week 36 (0.06, -0.03 to 0.15, p = 0.187), and no significant effect of group-by-time interaction on the HBsAg level throughout the trial (p = 0.814). The occurrence of total adverse events between the two groups was comparable (9 [31.0%] of 29 vs. 5 [16.1%] of 31, p = 0.227) and no patient experienced serious adverse events during the study., Conclusion: Although it was safe, metformin add-on therapy did not accelerate HBsAg clearance in entecavir-treated patients with HBeAg-negative CHB., Competing Interests: Conflicts of interest FSW has received a grant from the Innovative Research Group Project of the National Natural Science Foundation of China. All other authors declare that they have no conflict of interest., (Copyright © 2022. Published by Elsevier España, S.L.U.)

The root canal systems of maxillary second molar (MSM) variations are complicated, especially the prevalence of fused roots and consequent merged and C-shaped canals, which represent a clinical challenge because canal configurations can be irregular and unpredictable. The purpose of this article was to present 2 cases with a C-shaped configuration diagnosed during root canal retreatment and perform a literature review of this MSM anatomy. Case 1 reports that two palatal root canals fused into a C-shaped configuration that finally formed an apical foramen, which was classified as Type D. Case 2 reflects the fusion of the distobuccal canal and palatal canal into a C-shaped configuration and the configuration was Type C, which was first reported in a case report. Nonsurgical retreatments were proposed and conducted. Evaluation at a 24-month recall revealed that the two patients were symptom-free, and radiographic examination revealed normal periapical tissue. This report serves to remind clinicians of the complexities of the root canal system and that possible anatomic variation should always be anticipated when formulating an effective root canal treatment plan. The use of CBCT imaging coupled with an operative dental microscope will be helpful in locating and identifying supernumerary canals when a preoperative periapical radiograph shows signs of a fused-rooted MSM., Competing Interests: The authors declare no conflict of interest., (© 2022 The Author(s).)