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As an essential mechanical component, a rolling bearing can exhibit multiple failure modes that may occur independently or in correlation with one another. A reliability analysis method that meticulously accounts for the interdependencies among various bearing failure modes is presented in this paper. The examination of wear and fatigue failure mechanisms in rolling bearings is carried out using the Physics of Failure (PoF) approach. By considering the influence of uncertain variables, the limit state functions for individual failure modes are formulated through the application of stress‐strength interference theory. In the context of wear failure, the limit state function is derived using working clearance as the characteristic quantity. On the other hand, the limit state function for fatigue failure is constructed with a focus on fatigue damage accumulation. The Copula function is used to characterize the relationship between wear failure and fatigue failure, and a reliability calculation model for rolling bearings is developed, considering the correlation between these failure modes. Ultimately, the proposed method is utilized to assess the reliability of bearings under two different sets of test conditions. The feasibility of this method is confirmed through test data, demonstrating its effectiveness in predicting bearing reliability. Through the application of this method, engineers can optimize bearing size parameters, select appropriate initial clearances, and enhance the reliability design of bearing. [ABSTRACT FROM AUTHOR]

Simple Summary: Potassium sorbate (PS) is widely utilized as a food preservative. In this study, Drosophila melanogaster was employed as a model organism to assess the potential toxicity of PS. We examined the impacts of PS on several physiological parameters and discovered that higher levels of PS intake significantly affected the majority of these parameters. Additionally, our data suggest that excessive PS consumption may alter the differentiation trajectory of intestinal stem cells (ISCs), possibly via the down-regulation of Notch signaling. These results offer important insights into the potential health risks associated with PS exposure. Potassium sorbate (PS) is a preservative widely used in the food, pharmaceutical, and cosmetics industries. Improper and careless use of PS can lead to various health issues and potential environmental problems. Drosophila is capable of making rapid and sensitive responses to stress or other stimuli. Here we utilized Drosophila as a model organism to evaluate the potential toxicity of PS. Our study revealed that PS ingestion reduced the lifespan and fecundity of Drosophila. In addition, excessive PS ingestion led to cell apoptosis and ROS accumulation in the midgut. Furthermore, PS intake also enhanced the mitophagy of midgut cells. Strikingly, PS affected the cell differentiation progression as well, leading to the production of more enteroendocrine (EE) cells. We further demonstrated that the expression of notch (N), a vital player in intestinal stem cell (ISC) differentiation, was down-regulated in the midgut. This indicates that the differentiation progression was affected potentially by repressing the N expression. [ABSTRACT FROM AUTHOR]

In this study, we use a dataset collected from eBay to analyze buyers' negative feedback ratings and associated textual comments. By using text mining and sentiment analysis, we identify seven key reasons why buyers post negative ratings: communication problems, shipping issues, product defects, payment refund problems, customer service issues, fraud, and product packaging. These seven reasons can be classified into three categories: (1) sellers' malicious fraudulence toward buyers, (2) factors likely under the control of sellers, and (3) factors not likely under the control of sellers. Drawing on these categories, we discuss how sellers can effectively reduce the likelihood that buyers post negative ratings. The most important things sellers can do to avoid negative ratings are to improve communications with buyers and to handle product shipping issues properly. In addition to posting the reasons for their negative ratings of sellers, the textual comments associated with negative feedback ratings may also include direct denouncements of sellers, such as buyers explicitly claiming a seller is a liar and warning other buyers to be cautious of the seller. We collectively call these actions buyers' denouncements against sellers. These denouncements have significant negative impacts on sellers' reputations. In this study, we use correlation analysis and logistic regression to investigate the factors that motivate buyers to denounce sellers. We find that, of the three categories of reasons why buyers post negative ratings, sellers' malicious fraudulence toward buyers and factors likely under the control of sellers are more likely to lead to buyers' denouncements of sellers, while factors not likely under the control of sellers are not likely to lead to buyers' denouncements of sellers. In addition, buyers' strong negative sentiment is also more likely to lead to their denouncement of sellers. Managerial implications of these findings are discussed. [ABSTRACT FROM AUTHOR]

Glypicans are closely associated with organ development and tumorigenesis in animals. Dally-like (Dlp), a membrane-bound glypican, plays pivotal roles in various biological processes in Drosophila. In this study, we observed that an excess of Dlp led to the malformation of legs, particularly affecting the distal part. Accordingly, the leg disc was shrunken and frequently exhibited aberrant morphology. In addition, elevated Dlp levels induced ectopic cell death with no apparent cell proliferation changes. Furthermore, Dlp overexpression in the posterior compartment significantly altered Wingless (Wg) distribution. We observed a marked expansion of Wg distribution within the posterior compartment, accompanied by a corresponding decrease in the anterior compartment. It appears that excess Dlp guides Wg to diffuse to cells with higher Dlp levels. In addition, the distal-less (dll) gene, which is crucial for leg patterning, was up-regulated significantly. Notably, dachshund (dac) and homothorax (hth) expression, also essential for leg patterning and development, only appeared to be negligibly affected. Based on these findings, we speculate that excess Dlp may contribute to malformations of the distal leg region of Drosophila, possibly through its influence on Wg distribution, dll expression and induced cell death. Our research advances the understanding of Dlp function in Drosophila leg development. [ABSTRACT FROM AUTHOR]

To quickly calibrate the discrete element parameters (DEP) of pellets with different moisture content (MC), the angle of repose (AoR) was taken as the target value to conduct experimental and simulation research on gluten pellets. The experimental method obtained the intrinsic parameters, contact parameters, and AoR of pellets with different moisture content. The parameters differed significantly under different moisture content (p < 0.05). The AoR‐MC model (R2 = 0.987) was established. The Plackett–Burman test, steepest ascent test, and center compound test were carried out to establish the AoR‐DEP model (R2 = 0.969) with a relative error less than or equal to 2.07%. The MC‐DEP model was derived, and verified by the side plate lifting method with a relative error less than or equal to 2.58%. This paper provides a new method for calibrating DEP under different moisture content. [ABSTRACT FROM AUTHOR]

eBay's feedback rating system is currently widely used. In this study, we examine if eBay's feedback rating types (+, 0, −) are consistent with the sentiments reflected in the textual comments posted by buyers. Using the datasets collected from eBay, we test the hypotheses associated with the research questions at three levels: individual, group, and total. Overall, the types of feedback ratings are consistent with the sentiments embedded in the textual comments. However, there are some issues with eBay's current feedback rating system: (1) at the individual level, the correlation coefficient between the ratings and the comments' sentiments is low at 0.4311 (<0.5). While the three types of ratings are symmetric, like (−1, 0, +1), buyers' textual comments have asymmetric distributions of sentiments among these three types. The three simple feedback ratings (+, 0, −) are not fully aligned with the sentiments revealed in the textual comments posted by buyers. We propose expanding the current three ratings into five ratings such as (−2, −1, 0, +1, +2), which might help remedy the issue. We contribute to the literature by tapping into this less-studied area vital to improving the online marketplace's efficiency. [ABSTRACT FROM AUTHOR]