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AbstractWe study an admission control model in revenue management with nonstationary and correlated demands over a finite discrete time horizon. The arrival probabilities are updated by current available information, that is, past customer arrivals and some other exogenous information. We develop a regret‐based framework, which measures the difference in revenue between a clairvoyant optimal policy that has access to all realizations of randomness a priori and a given feasible policy which does not have access to this future information. This regret minimization framework better spells out the trade‐offs of each accept/reject decision. We proceed using the lens of approximation algorithms to devise a conceptually simple regret‐parity policy. We show the proposed policy achieves 2‐approximation of the optimal policy in terms of total regret for a two‐class problem, and then extend our results to a multiclass problem with a fairness constraint. Our goal in this article is to make progress toward understanding the marriage between stochastic regret minimization and approximation algorithms in the realm of revenue management and dynamic resource allocation. © 2016 Wiley Periodicals, Inc. Naval Research Logistics 63: 433–448, 2016

Abstract
The likelihood of threatening events is often simplified for members of the public and presented as risk categories such as the "watches" and "warnings" currently issued by National Weather Service in the United States. However, research (e.g., Joslyn and LeClerc) suggests that explicit numeric uncertainty information—for example, 30%—improves people's understanding as well as their decisions. Whether this benefit extends to dynamic situations in which users must process multiple forecast updates is as yet unknown. It may be that other likelihood expressions, such as color coding, are required under those circumstances. The experimental study reported here compared the effect of the categorical expressions "watches" and "warnings" with both color-coded and numeric percent chance expressions of the likelihood of a tornado in a situation with multiple updates. Participants decided whether and when to take shelter to protect themselves from a tornado on each of 40 trials, each with seven updated tornado forecasts. Understanding, decision quality, and trust were highest in conditions that provided percent chance information. Color-coded likelihood information inspired the least trust and led to the greatest overestimation of likelihood and confusion with severity information of all expressions.

Abstract
There are lingering questions about the effectiveness of the watch, warning, and advisory system (WWA) used to convey weather threats in the United States. Recently there has been a shift toward alternative communication strategies such as the impact-based forecast. The study reported here compared users' interpretation of a color-coded impact-based prototype designed for email briefings, to a legacy WWA format. Participants, including emergency managers and members of the public, saw a weather briefing and rated event likelihood, severity, damage, and population affected. Then they recommended emergency response actions. Each briefing described the severity of the weather event and the degree of impact on population and property. In one condition a color-coded impacts scale was added to the text description. In another, an advisory and/or warning was added to the text description. These were compared with the text-only control. Both emergency managers and members of the public provided higher ratings for event likelihood, severity, damage, and population affected and recommended a greater response for higher impact levels regardless of format. For both groups, the color-coded format decreased ratings for lower-impact events. Among members of the public, the color-coded format also led to increases for many ratings and greater response at higher levels relative to the other two conditions. However, the highest ratings among members of the public were in the WWA condition. Somewhat surprisingly, the only effect of the WWA format on emergency managers was to reduce action recommendations, probably because of the inclusion of the "advisory" in some briefings.

Xiaohan Ren,1,* Shangqian Wang,1,* Xinglin Chen,1,* Xiyi Wei,1,* Guangyao Li,1,* Shancheng Ren,2 Tongtong Zhang,1 Xu Zhang,1 Zhongwen Lu,1 Zebing You,1 Zengjun Wang,1 Ninghong Song,1 Chao Qin1 1The State Key Laboratory of Reproductive; Department of Urology, The First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, People's Republic of China; 2Department of Urology, Shanghai Changhai Hospital, Second Military Medical University, Shanghai, People's Republic of China*These authors contributed equally to this workCorrespondence: Chao Qin; Ninghong SongThe State Key Laboratory of Reproductive; Department of Urology, The First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, People's Republic of ChinaTel +86 13776678978; +86 15651728807Email nmuqinchao@163.com; songninghong_urol@163.comBackground: Since December 2019, the novel coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), first spread quickly in Wuhan, China, then globally. Based on previously published evidence, ACE2 and TMPRSS2 are both pivotal entry molecules that enable cellular infection by SARS-CoV-2. Also, increased expression of pro-inflammatory cytokines, or a "cytokine storm," is associated with multiple organ dysfunction syndrome often observed in critically ill patients.Methods: We investigated the expression pattern of ACE2 and TMPRSS2 in major organs in the human body, especially in specific disease conditions. Multiple sequence alignment of ACE2 in different species was used to explain animal susceptibility. Moreover, the cell-specific expression patterns of ACE2 and cytokine receptors in the urinary tract were assessed using single-cell RNA sequencing (scRNA-seq). Additional biological relevance was determined through Gene Set Enrichment Analysis (GSEA) using an ACE2-specific signature.Results: Our results revealed that ACE2 and TMPRSS2 were highly expressed in genitourinary organs. ACE2 was highly and significantly expressed in the kidney among individuals with chronic kidney diseases or diabetic nephropathy. In single cells, ACE2 was primarily enriched in gametocytes in the testis and renal proximal tubules. The receptors for pro-inflammatory cytokines, especially IL6ST, were notably concentrated in endothelial cells, macrophages, spermatogonial stem cells in the testis, and renal endothelial cells, which suggested the occurrence of alternative damaging autoimmune mechanisms.Conclusion: This study provided new insights into the pathogenic mechanisms of SARS-CoV-2 that underlie the clinical manifestations observed in the human testis and kidney. These observations might substantially facilitate the development of effective treatments for this rapidly spreading disease.Keywords: genitourinary organs, pro-inflammatory cytokine receptors, kidney, testis, SARS-CoV-2