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Problem definition: We study stochastic periodic-review inventory systems with lost sales, where the decision maker has no access to the true demand distribution a priori and can only observe historical sales data (referred to as censored demand) and feature information about the demand. In an inventory system, excess demand is unobservable because of inventory constraints, and sales data alone cannot fully recover the true demand. Meanwhile, feature information about the demand is abundant to assist inventory decisions. We incorporate features for inventory systems with censored demand. Methodology/results: We propose two feature-based inventory algorithms called the feature-based adaptive inventory algorithm and the dynamic shrinkage algorithm. Both algorithms are based on the stochastic gradient descent method. We measure the performance of the proposed algorithms through the average expected regret in finite periods: that is, the difference between the cost of our algorithms and that of a clairvoyant optimal policy with access to information, which is acting optimally. We show that the average expected cost incurred under both algorithms converges to the clairvoyant optimal cost at the rate of O(log T/T) for the perishable inventory case and O(1/T) for the nonperishable inventory case. The feature-based adaptive inventory algorithm results in high volatility in the stochastic gradients, which hampers the initial performance of regret. The dynamic shrinkage algorithm uses a shrinkage parameter to adjust the gradients, which significantly improves the initial performance. Managerial implications: This paper considers feature information. The idea of dynamic shrinkage for the stochastic gradient descent method builds on a fundamental insight known as the bias-variance trade-off. Our research shows the importance of incorporating the bias-variance in a dynamic environment for inventory systems with feature information. Funding: W. T. Huh acknowledges support from the NSERC Discovery Grants [Grant RGPIN 2020-04213] and the Canada Research Chair Program. The work of Y. Rong was supported by the National Natural Science Foundation of China [Grants 72025201, 72331006, and 72221001]. Supplemental Material: The online appendix is available at https://doi.org/10.1287/msom.2021.0135. [ABSTRACT FROM AUTHOR]

Facial recognition payment technology (FR) has the potential to disrupt the offline retailing industry by automating the payment process. However, some firms that adopted FR payment technology have experienced only moderate success, and many customers have expressed frustration using FR payment technology. By utilizing data sets from three retail chains, we find that customers are less likely to use FR payment technology during self-checkouts when more customers are in line behind them, waiting and watching (the social presence effect), and when more preceding customers use the other payment technology (the herding effect). These findings imply that (1) the design of FR technology can be improved to alleviate the social presence effect (such as adding a privacy screen filter or beautify the appearance of the consumer's image), and (2) monetary incentives may be used to attract more users by leveraging the herding effect. Although facial recognition (FR) payment technology can be more convenient for customers, it is still not consistently used by many customers in retail. Using transaction data from three retail chains, we develop econometric models and an estimation strategy for examining the social presence and herding effects that affect FR payment technology use. Our key findings are as follows: (1) Customers are less likely to use FR payment technology when more customers are in line behind them, waiting and potentially watching—the social presence effect. (2) Customers are more likely to use FR payment technology when more preceding customers use FR payment technology—the herding effect. (3) Customers with more experience using FR payment technology are subject to a weaker social presence effect. The marginal social presence effect can result in a 4.75% reduction in the probability of the focal customer using FR payment technology, and the potential social presence effect can be as high as 48.42%. When the focal customer has one additional experience in using FR payment technology, the social presence effect is reduced by 7.79%. The herding effect can result in a 20.90% increase in the probability of the focal customer using FR payment technology. Theoretical and managerial implications are discussed. History: Rajiv Kohli served as the senior editor for this article. Funding: Y. Rong's work was supported by the National Natural Science Foundation of China [Grants 72025201 and 72221001]. X. Tian's work was supported by the National Natural Science Foundation of China [Grants 72172145 and 71932002], the Beijing Natural Science Foundation [Grant 9212020], and the Fundamental Research Funds for the Central Universities. J. Gao's work was supported by the National Natural Science Foundation of China [Grant 72232001]. Supplemental Material: The online appendix is available at https://doi.org/10.1287/isre.2023.1205. [ABSTRACT FROM AUTHOR]

This paper describes the operations of most on-demand meal delivery platforms and discusses how empirical research can improve the operational performance of these platforms. To support and encourage more studies on the operations of on-demand delivery platforms, we provide a unique data set obtained from a meal delivery platform in China. This data set contains operational level data sampled from July 1 to August 31, 2015, in Hangzhou, China. The data set includes information about order placements, order deliveries, restaurants, drivers, weather and traffic conditions, and so on. We also review recent studies on meal delivery platforms and suggest research opportunities for improving delivery performance. [ABSTRACT FROM AUTHOR]

Purpose: Previous systematic review suggested a beneficial effect of progressive muscle relaxation (PMR) for cancer patients receiving chemotherapy. However, poor quality of eligible studies which included in previous systematic review impaired the reliability and validity of findings. The aim of the present systematic review was to further assess the value of PMR in chemotherapy-induced nausea and vomiting. Methods: We assigned two independent investigators to search potential studies in PubMed, Cochrane Controlled Register of Trial (CENTRAL), Cumulative Index to Nursing and Allied Health Literature (CINAHL), China Biomedical Literature database (CBM), China National Knowledge Infrastructure (CNKI), and Wanfang Data database. We used data extraction sheet to extract essential information, and used the Cochrane risk of bias assessment tool to appraise the quality of eligible studies. Finally, we qualitatively summarized the results of all included studies. Results: Six studies enrolling 288 patients were included finally. Of these 6 studies, three were labeled as moderate quality and the remaining studies were low quality. All included studies consistently suggested that PMR has a positive effect on chemotherapy-induced nausea and vomiting, especially on the incidence, frequency, and degree of delayed nausea and vomiting. Conclusion: Independent studies indicated that PMR was a beneficial approach of preventing and alleviating chemotherapy-induced nausea and vomiting among cancer patients. However, further studies enrolling other types of primary tumors should be designed in order to increase the generality of PMR because studies which were included in the present systematic review mainly considered patients with lung cancer and breast cancer. Moreover, future studies with high quality and large-scale are also warranted in order to address the limitations in the present systematic review such as poor quality and limited data of eligible studies. [ABSTRACT FROM AUTHOR]

This article comprises two parts: the first in which the author examines the ramifications of the process of stabilising Afghanistan and the second in which he discusses a possible role for the Russia, India and China (RIC) trilateral. The author cites the results of a survey conducted in all thirty-four provinces of Afghanistan, which mainly concerns the attitude of the people and the national mood in 2004 and 2008. The results revealed very low levels of confidence. The crux of the problem was that the war cannot be won, nor the Afghan situation addressed by the military approach. The situation is extremely complex and tense mainly because of the lack of strategic coherence within the West and their attempt to promote a Western set-up in Afghanistan without heed to, or respect for, the Afghan condition. The focus has been only on capturing the Al-Qaeda through Operation Enduring Freedom. The role of Pakistan was also quite complex and the question was whether it should be seen as part of the problem or part of the solution. The American's Afghan policy was insensitive to the geopolitical complexity in the region. Since all three countries were affected by the situation in Afghanistan, stability in this area was in the interests of all. It was necessary, therefore, to make the trilateral more relevant and the election in September 2009 provided a good occasion to look for a common agenda and adopt a proactive stance. The RIC could encourage the exploration of a new political set-up in Afghanistan by taking into account its national conditions. They could also stress a leading role for the United Nations and explore a regional approach, whereby the various organisations in the region could be interconnected to explore solutions. [ABSTRACT FROM AUTHOR]

The article presents a political analysis of relations between India, China, and Russia. It also discusses the academic study of diplomatic relations and foreign policy presented at the Seventh China-India-Russia Academic Trilateral Conference, held October 2007 in Moscow, Russia. The author suggests that participants of the conference should create a task force to study aspects of tripartite political cooperation, create a web-based newsletter to post ongoing academic studies and encourage academic communication, and create an Internet database focused on the study of trilateral cooperation.

[Display omitted] • Soil organic carbon and labile organic carbon fractions decreased in the subsidence waterlogging areas. • The largest carbon depletion was observed in the 0–10 cm soil layer. • The liability of particulate organic carbon was highest among the three types of labile organic carbon fractions. • Labile organic carbon fractions were closely correlated with soil properties. • The shallow waterlogging area has the best carbon accumulation potential. The restoration of subsidence waterlogging areas has the potential to facilitate carbon accumulation in coal mining areas with high ground water tables. However, the soil organic carbon (SOC) and labile organic carbon (LOC) have not been sufficiently investigated in different types of subsidence waterlogging areas. In this study, SOC and LOC fractions, including light fraction organic carbon (LFOC), particulate organic carbon (POC), and dissolved organic carbon (DOC) within 0–50 cm soil profiles, were determined in a reference cropland (RC) and three types of subsidence waterlogging area in Xinglongzhuang Coal Mine, Shandong Province, China, including an aquaculture waterlogging area (AWA), deep waterlogging area (DWA) and shallow waterlogging area (SWA) with water depths of 1.8, 3.2, and 0.65 m, respectively. Compared with RC, SOC and LOC decreased by 4.13%, 25.03%, and 77.91% in SWA, DWA, and AWA, respectively. The largest depletion was in the 0–10 cm layer, indicating that there was a time lag for the recovery of the total functional pools of SOC after subsidence. The lability of POC was highest among the three types of LOC fractions, indicating that mining subsidence triggered soil redistribution and impacted on carbon accumulation. With comparatively little soil profile interference in DWA and SWA, the lability of LFOC and POC decreased with soil depth, while the DOC increased. There was a large discrepancy in AWA, with the lability of LOC fractions fluctuating because of soil disturbance by intensive engineering. The LOC fractions were closely associated and correlated with soil properties, especially total nitrogen (TN) and total phosphorus (TP). Restoration and management of the subsidence waterlogging areas have a vital impact on the SOC pool. It was concluded that shallow water and a natural geomorphology-based topography, with little soil disturbance, well-developed vegetation communities, and continuous monitoring of soil and water properties would facilitate the carbon accumulation process. [ABSTRACT FROM AUTHOR]

Plasma transthyretin may be engaged in glucose regulation. We aimed to investigate the association between plasma transthyretin levels and the risk of newly diagnosed T2DM and impaired glucose regulation (IGR) in a Chinese population. We conducted a case-control study including 1244 newly diagnosed T2DM patients, 837 newly diagnosed IGR patients, and 1244 individuals with normal glucose tolerance (NGT) matched by sex and age. Multivariate logistic regression analysis was utilized to estimate the independent association of plasma transthyretin concentrations with the risk of T2DM and IGR. Plasma transthyretin concentrations were significantly higher in T2DM and IGR patients compared with control subjects (p < 0.005). After multiple adjustment and comparison with the lowest quartile of plasma transthyretin concentrations, the odds ratios (95% confidence intervals) of T2DM and IGR in the highest quartile were 2.22 (1.66, 2.98) and 2.29 (1.72, 3.05), respectively. Plasma transthyretin concentrations also showed a great performance in predicting the risk of T2DM (AUC: 0.76). Moreover, a potential nonlinear trend was observed. Our results demonstrated that higher plasma transthyretin concentrations, especially more than 290 mg/L, were associated with an increased risk of T2DM and IGR. Further studies are warranted to confirm our findings and elucidate the potential mechanisms.