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Recently, the Value-at-Risk (VaR) framework was introduced for the routing problem of a single hazmat trip. In this paper, we extend the VaR framework in two important ways.First, we show how to apply the VaR concept to a more realistic multi-trip multi-hazmat type framework, which determines routes that minimize the global VaR value while satisfying equity constraints. Second, we show how to embed the algorithm for the single hazmat trip problem into a Lagrangian relaxation framework to obtain an efficient solution method for this general case. We test our computational experience based on a real-life hazmat routing scenario in the Albany district of New York State. Our results indicate that one can achieve a high degree of risk dispersion while controlling the VaR value within the desired confidence level.

ObjectiveTo evaluate the quality of clinical practice guidelines (CPGs) for otorhinolaryngology in China.Materials and MethodsA systematic search of relevant literature databases (CBM, WANFANG, VIP, CNKI, China Guideline Clearinghouse) published between 1978 and March 2012 was undertaken to identify and select CPGs related to otorhinolaryngology. Four independent reviewers assessed the eligible guidelines using the Appraisal of Guidelines for Research and Evaluation (AGREE II) instrument. Their degree of agreement was evaluated using the intraclass correlation coefficient (ICC).ResultFrom 170 citations, 21 relevant guidelines were included. The overall agreement among reviewers was moderate (ICC = 0.87; 95% confidence interval [CI], 0.78–0.91). The scores for each of the AGREE domains were the following: “scope and purpose” (mean ± standard error [SE] = 45.4±4.4; ICC = 0.92), “stakeholder involvement” (mean ± SE = 30.4±3.1; ICC = 0.81), “rigor of development” (mean ± SE = 20.9±2.8; ICC = 0.87), “clarity of presentation” (mean ± SE = 48.8±3.7; ICC = 0.80), “applicability” (mean ± SE = 12.6±1.7; ICC = 0.72), and “editorial independence” (mean ± SE = 6.2±0.8; ICC = 0.76). Three guidelines (14%) mentioned updates, and the average update frequency was 7 years. None used the GRADE system.ConclusionThe quality of otorhinolaryngology guidelines in China is low. Greater efforts are needed to provide high-quality guidelines that serve as a useful and reliable tool for clinical decision-making in this field.

Objective: Lianhua Qingwen combined with Western medicine (LHQW+WM) has been proposed as a viable treatment for coronavirus disease 2019 . Interestingly, umbrella reviews of systematic reviews (SRs), which provide the most comprehensive evidence, are the best evidence in evidence-based medicine. Therefore, an umbrella review of SRs that summarizes and evaluates the efficacy of LHQW+WM for COVID-19 is urgently required.Methods: Overall, 6 databases were used to conduct a comprehensive literature search from inception to January 22, 2022. The corrected covered area (CCA) was used to analyze the overlapping between SRs. Meta-analysis was conducted when that of the included SRs was inappropriate. A MeaSurement Tool to Assess Systematic Reviews (AMSTAR-2) was also employed to assess the quality of the included SRs.Results: In total, 12 SRs were identified, which included 12 unique primary studies. The included SRs ranged in quality from moderate to critically low and had an extremely high CCA (36.4%). Compared to conventional treatment, LHQW+WM showed efficacy concerning fatigue recovery [risk ratio (RR) = 1.69, 95% confidence interval (CI): 1.04-2.73, n = 2, I 2 = 0%], cough recovery (RR = 1.65, 95% CI: 1.09-2.51, n = 3, I 2 = 39.1%), and overall effective rates (RR = 1.17, 95% CI: 1.07-1.28, n = 3, I 2 = 17.5%).Conclusion: LHQW+WM may improve the clinical symptoms of patients with COVID-19; however, the results should be interpreted cautiously because of the rigorous processes in the included SRs.

Several observational studies have shown that metformin can modify the risk and survival of colorectal cancer (CRC) in patients with diabetes mellitus, although the magnitude of this relationship has not been determined. We conducted an updated systematic review and meta-analysis to analyze the association between metformin and CRC mortality and searched relevant databases up to July 2016. The primary outcome was overall survival (OS). Secondary outcomes were cancer-specific survival (CS) and disease-free survival (DFS). Summary hazard ratios (HRs) were calculated using a random-effects model. Seventeen studies enrolling 269,417 participants were eligible for inclusion. Comparing with non-metformin users in diabetic CRC patients, the summary HRs for OS in metformin users were 0.69 (95% CI, 0.61-0.77). Subgroup analyses stratified by the study characteristics and sensitivity analysis by the trim-and-fill method (adjusted HR 0.77, 95% CI, 0.67-0.87) confirmed the robustness of the results. However, significant OS benefit was noted in patients with stage II and III disease. Five studies reported the CRC prognosis for CS and three for DFS; metformin intake was significantly associated with patient CS (HR 0.75, 95% CI, 0.59-0.94), but not DFS (HR 0.38, 95% CI, 0.13-1.17). Our findings suggest that metformin intake is associated with improved survival outcomes in terms of OS and CS in CRC patients with diabetes, particular for OS in stage II and stage III patients. Further studies should be conducted to determine CRC survival between metformin use and patient specific clinical and molecular profiles.

In this paper, we propose a dual toll pricing method to mitigate risk of hazardous materials (hazmat) transportation. We aim to simultaneously control both regular and hazmat vehicles to reduce the risk. In our model, we incorporate a new risk measure to consider durationpopulation-frequency of hazmat exposure. We first formulate the model as a Mathematical Program with Equilibrium Constraints (MPEC). Then we decompose the MPEC formulation into first-stage and second-stage problems. Separate methods are developed to solve each stage. A numerical example is provided and possible extensions are discussed.

This work proposed a synthesis route of ZSM‐5 via the hydrothermal method with premixing in a stirred tank reactor (STR). Effects of various operating conditions, including pre‐mixing time, molar ratio of SiO2/Al2O3, TPAOH (organic template agents) concentration, NaCl (alkali metal cations) concentration, crystallization temperature, and crystallization reaction time, on the average particle size (PS) and particle size distribution (PSD) were investigated. It was found that the pre‐mixing time in the STR significantly affect the formation of proto‐nuclei in premixing process and crystal growth in hydrothermal reaction process, and consequently influence the PS and PSD of the prepared ZSM‐5. ZSM‐5 with good thermal stability, a PS of 380 nm, PSD of 0.17–0.9 µm, pore diameter of 2.31 nm, pore volume of 0.19 cm3 · g−1 and specific surface area of 337.25 m2 ·  g−1 were obtained under the optimal conditions of a crystallization reaction time of 24 h, a crystallization temperature of 130 °C, a molar ratio of SiO2/Al2O3 of 200, a TPAOH concentration of 3.5 mol · L−1, NaCl concentration of 0.3 mol · L−1, and a pre‐mixing time of 5 h. This work indicated that the operating conditions including premixing time have a significant effect on its PS and PSD.

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