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Autonomous vehicles (AVs) must fulfill adequate safety requirements before formal application, and performing an effective functional evaluation to verify vehicle safety requires extensive testing in different scenarios. However, it is crucial to rationalize the application of different scenarios to support different testing needs; thus, one of the current challenges limiting the development of AVs is the critical evaluation of scenarios, i.e., the lack of quantitative criteria for scenario design. This study introduces a method using the Spherical Fuzzy-Analytical Network Process (SF-ANP) to evaluate these scenarios, addressing their inherent risks and complexities. The method involves constructing a five-layer model to decompose scenario elements and using SF-ANP to calculate weights based on element interactions. The study evaluates 700 scenarios from the China In-depth Traffic Safety Study–Traffic Accident (CIMSS-TA) database, incorporating fuzzy factors and element weights. Virtual simulation of vehicles in the scenarios was performed using Baidu Apollo, and the performance of the scenarios was assessed by collecting the vehicle test results. The correlation between the obtained alternative safety indicators and the quantitative values confirms the validity and scientific validity of this approach. This will provide valuable guidance for categorizing audiovisual test scenarios and selecting corresponding scenarios to challenge different levels of vehicle functionality. At the same time, it can be used as a design basis to generate a large number of effective scenarios to accelerate the construction of scenario libraries and promote commercialization of AVs. [ABSTRACT FROM AUTHOR]

Ultrafast lasers have significantly contributed to the advancement of research and technology; however, high‐intensity lasers bring potential risks to precision instruments and the human eye. Developing optical limiting (OL) devices capable of reasonably controlling laser energy to an acceptable energy level is imperative. Nevertheless, achieving both exceptional OL performance and broad‐spectrum laser intensity tunability proves highly challenging. In this work, the synthesis of a porphyrin‐based 2D polymer (Por‐2DP) using a template‐assisted self‐coupling polymerization, constructing a 2D framework through the carbon‐carbon single bond coupling of porphyrin monomer is presented. The resultant Por‐2DP demonstrates remarkable broadband nonlinear absorption performance, spanning the visible and near‐infrared spectral regions under an ultrafast pulse laser (35 fs) for the first time. OL thresholds at excitation wavelengths of 515, 800, and 1550 nm are determined to be 1.44, 0.48, and 0.54 mJ cm−2, respectively, surpassing reported 2D materials to date. Additionally, the Por‐2DP exhibits prominent photostability, enabling sustained operation under intense light conditions for a long time, thereby enhancing OL practical applicability. This study not only introduces a novel OL material and device but also promotes the application of innovative 2D organic polymers in NLO field. [ABSTRACT FROM AUTHOR]

Kagome superconductors AV3Sb5 (A = K, Rb and Cs) have attracted much recent attention due to the coexistence of multiple exotic orders. Among them, the charge density wave (CDW) order has been shown to host various unconventional behaviors. Here, we investigate the CDW order by a combination of both bulk and surface doping methods. While element substitutions in bulk doping change both carriers and the crystal lattice, the surface doping primarily tunes the carrier concentration. As such, our results reveal a two-dimensional phase diagram of the CDW in doped CsV3Sb5. In the lightly bulk doped regime, the existence of CDW order is reversible by tuning the carrier concentration. But excessive bulk doping permanently destroys the CDW, regardless of the carrier doping level. These results provide insights to the origin of the CDW from both electronic and structural degrees of freedom. They also open an avenue for manipulating the exotic CDW order in Kagome superconductors. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the efficacy and safety of 0.01% atropine (AT) in combination with different optical treatments for controlling myopia in Chinese children., Methods: This retrospective study analyzed 341 Chinese children aged 6-11 years with myopia between -0.50 D and -3.0 D between January 2022 and May 2023. The fast-progressing, myopic children received three optical treatments combined with 0.01 % atropine: 75 children with single-vision spectacles and atropine (SV + AT), 162 children with defocus-incorporated multi-segment spectacles and atropine (DIMS + AT), or 104 children with orthokeratology and atropine (OK + AT). The changes in spherical equivalent refraction (SER), axial length (AL), intraocular pressure (IOP), and amplitude of accommodation (AMP) were observed at 6-month and 1-year intervals., Results: After controlling for baseline variables, at 6 months, the increase in adjusted AL was significantly greater in the SV + AT group than in the DIMS + AT group (difference = 0.13 mm, 95 % CI: 0.07-0.20, P < 0.05) and in the OK + AT group (difference = 0.09 mm, 95 % CI: 0.09-0.17, P < 0.05). A more significant progression in adjusted SER was also observed in the SV + AT group than in the DIMS group (difference = -0.20D, 95 % CI: -0.29 to -0.11, P < 0.05). At 12 months, the greatest increase in adjusted AL was observed in the SV + AT group, with a statistically significant difference of 0.24 mm (95 % CI: 0.19-0.29, P < 0.05) compared with the DIMS group and a difference of 0.19 mm (95 % CI: 0.13-0.25, P < 0.05) compared with the OK + ST group. Similarly, a more significant progression in adjusted SER was observed in the SV + AT group than in the DIMS group (difference = -0.36 D, 95 % CI: -0.48 to -0.24, P < 0.05)., Conclusions: This study suggested that 0.01% atropine combined with DIMS or orthokeratology may be viable for controlling low myopia in fast-progressing, myopic children., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Objective: Autonomous vehicles (AVs) have the potential to revolutionize the future of mobility by significantly improving traffic safety. This study presents a novel method for validating the safety performance of AVs in high-risk scenarios involving powered 2-wheelers (PTWs). By generating high-risk scenarios using in-depth crash data, this study is devoted to addressing the challenge of public road scenarios in testing, which often lack the necessary complexity and risk to effectively evaluate the capabilities of AVs in high-risk situations., Method: Our approach employs a Wasserstein generative adversarial network (WGAN) to generate high-risk scenes, particularly focusing on PTW scenarios. By extracting 314 car-to-PTW crashes from the China In-depth Mobility Safety Study-Traffic Accident database, we simulate outcomes using PC-Crash software. The data are divided into scenes at 0.1-s intervals, with WGAN generating numerous high-risk scenes. By using a cumulative distribution function (CDF), we sampled and analyzed the vehicle's dynamic information to generate complete scenarios applicable to the test. The validation process involves using the SVL Simulator and the Baidu Apollo joint simulation platform to evaluate the AV's driving behavior and interactions with PTWs., Results: This study evaluates model generation results by comparing distributions using Wasserstein distance as an indicator. The generator converges after approximately 200 epochs, with the iterator converging quickly. Subsequently, 10,000 new scenes are then generated. The distribution of several key parameters in the generated scenes can be found to approximate that of the original scenes. After sampling, the usability of generated scenarios is 64.76%. Virtual simulations confirm the effectiveness of the scenario generation method, with a generated scenario crash rate of 16.50% closely reflecting the original rate of 15.0%, showcasing the method's capacity to produce realistic and hazardous scenarios., Conclusions: The experimental results suggest that these scenarios exhibit a level of risk similar to the original crashes and are effective for testing AVs. Consequently, the generated scenarios enhance the diversity of the scenario library and accelerate the overall testing process of AVs.

Limited access to food stores is often linked to higher health risks and lower community resilience. Socially vulnerable populations experience persistent disparities in equitable food store access. However, little research has been done to examine how people's access to food stores is affected by natural disasters. Previous studies mainly focus on examining potential access using the travel distance to the nearest food store, which often falls short of capturing the actual access of people. Therefore, to fill this gap, this paper incorporates human mobility patterns into the measure of actual access, leveraging large-scale mobile phone data. Specifically, we propose a novel enhanced two-step floating catchment area method with travel preferences (E2SFCA-TP) to measure accessibility, which extends the traditional E2SFCA model by integrating actual human mobility behaviors. We then analyze people's actual access to grocery and convenience stores across both space and time under the devastating winter storm Uri in Harris County, Texas. Our results highlight the value of using human mobility patterns to better reflect people's actual access behaviors. The proposed E2SFCA-TP measure is more capable of capturing mobility variations in people's access, compared with the traditional E2SFCA measure. This paper provides insights into food store access across space and time, which could aid decision making in resource allocation to enhance accessibility and mitigate the risk of food insecurity in underserved areas., (© 2024 Society for Risk Analysis.)

Confronting the continuing risk of an attack, security systems have adopted target-hardening strategies through the allocation of security measures. Most previous work on defensive resource allocation considers the security system as a monolithic architecture. However, systems such as schools are typically characterized by multiple layers, where each layer is interconnected to help prevent single points of failure. In this paper, we study the defensive resource allocation problem in a multilayered system. We develop two new resource allocation models accounting for probabilistic and strategic risks, and provide analytical solutions and illustrative examples. We use real data for school shootings to illustrate the performance of the models, where the optimal investment strategies and sensitivity analysis are presented. We show that the defender would invest more in defending outer layers over inner layers in the face of probabilistic risks. While countering strategic risks, the defender would split resources in each layer to make the attacker feel indifferent between any individual layer. This paper provides new insights on resource allocation in layered systems to better enhance the overall security of the system., (© 2024 Society for Risk Analysis.)

Aims: This study aimed to investigate the clinical characteristics and outcomes associated with culture-negative limb osteomyelitis patients., Methods: A total of 1,047 limb osteomyelitis patients aged 18 years or older who underwent debridement and intraoperative culture at our clinic centre from 1 January 2011 to 31 December 2020 were included. Patient characteristics, infection eradication, and complications were analyzed between culture-negative and culture-positive cohorts., Results: Of these patients, 264 (25.2%) had negative cultures. Patients with a culture-negative compared with a culture-positive status were more likely to have the following characteristics: younger age (≤ 40 years) (113/264 (42.8%) vs 257/783 (32.8%); p = 0.004), a haematogenous aetiology (75/264 (28.4%) vs 150/783 (19.2%); p = 0.002), Cierny-Mader host A (79/264 (29.9%) vs 142/783 (18.1%); p < 0.001), antibiotic use before sampling (34/264 (12.9%) vs 41/783 (5.2%); p＜0.001), fewer taken samples (n＜3) (48/264 (18.2%) vs 60/783 (7.7%); p＜0.001), and less frequent presentation with a sinus (156/264 (59.1%) vs 665/783 (84.9%); p < 0.001). After initial treatments of first-debridement and antimicrobial, infection eradication was inferior in culture-positive osteomyelitis patients, with a 2.24-fold increase (odds ratio 2.24 (95% confidence interval 1.42 to 3.52)) in the redebridement rate following multivariate analysis. No statistically significant differences were found in long-term recurrence and complications within the two-year follow-up., Conclusion: We identified several factors being associated with the culture-negative result in osteomyelitis patients. In addition, the data also indicate that culture negativity is a positive prognostic factor in early infection eradication. These results constitute the basis of optimizing clinical management and patient consultations., Competing Interests: The authors declare grants or contracts from National Natural Science Foundation of China (82202707), Chongqing Natural Science Foundation Program (CSTB2023NSCQ-BHX0202), Shanghai Natural Science Foundation Program (22ZR1476600), and Changning District Health Commission Fund (20234Y041), all of which are related to this study., (© 2024 The British Editorial Society of Bone & Joint Surgery.)

Aims: The aim of the present study was to assess the outcomes of the induced membrane technique (IMT) for the management of infected segmental bone defects, and to analyze predictive factors associated with unfavourable outcomes., Methods: Between May 2012 and December 2020, 203 patients with infected segmental bone defects treated with the IMT were enrolled. The digital medical records of these patients were retrospectively analyzed. Factors associated with unfavourable outcomes were identified through logistic regression analysis., Results: Among the 203 enrolled patients, infection recurred in 27 patients (13.3%) after bone grafting. The union rate was 75.9% (154 patients) after second-stage surgery without additional procedures, and final union was achieved in 173 patients (85.2%) after second-stage surgery with or without additional procedures. The mean healing time was 9.3 months (3 to 37). Multivariate logistic regression analysis of 203 patients showed that the number (≥ two) of debridements (first stage) was an independent risk factor for infection recurrence and nonunion. Larger defect sizes were associated with higher odds of nonunion. After excluding 27 patients with infection recurrence, multivariate analysis of the remaining 176 patients suggested that intramedullary nail plus plate internal fixation, smoking, and an allograft-to-autograft ratio exceeding 1:3 adversely affected healing time., Conclusion: The IMT is an effective method to achieve infection eradication and union in the management of infected segmental bone defects. Our study identified several risk factors associated with unfavourable outcomes. Some of these factors are modifiable, and the risk of adverse outcomes can be reduced by adopting targeted interventions or strategies. Surgeons can fully inform patients with non-modifiable risk factors preoperatively, and may even use other methods for bone defect reconstruction., Competing Interests: All authors report grants from the National Natural Science Foundation of China (82202707) and the Chongqing Natural Science Foundation Program (CSTB2023NSCQ-BHX0202), related to this study., (© 2024 The British Editorial Society of Bone & Joint Surgery.)

Background: Inflammatory bowel disease (IBD) is often associated with complex extraintestinal manifestations. The incidence of nonalcoholic fatty liver disease (NAFLD) in IBD populations is increasing yearly. However, the mechanism of interaction between NAFLD and IBD is not clear. Consequently, this study aimed to explore the common genetic characteristics of IBD and NAFLD and identify potential therapeutic targets., Materials and Methods: Gene chip datasets for IBD and NAFLD were obtained from the Gene Expression Omnibus (GEO) database. Weighted gene co-expression network analysis (WGCNA) was performed to identify modules in those datasets related to IBD and NAFLD. ClueGO was used for biological analysis of the shared genes between IBD and NAFLD. Based on the Human MicroRNA Disease Database (HMDD), microRNAs (miRNAs) common to NAFLD and IBD were obtained. Potential target genes for the miRNAs were predicted using the miRTarbase, miRDB, and TargetScan databases. Two-sample Mendelian randomization (MR) and two-way MR were used to explore the causal relationship between Interleukin-17 (IL-17) and the risk of IBD and NAFLD using data from GWAS retrieved from an open database., Results: Through WGCNA, gene modules of interest were identified. GO enrichment analysis using ClueGO suggested that the abnormal secretion of chemokines may be a common pathophysiological feature of IBD and NAFLD, and that the IL-17-related pathway may be a common key pathway for the pathological changes that occur in IBD and NAFLD. The core differentially expressed genes (DEGs) in IBD and NAFLD were identified and included COL1A1, LUM, CCL22, CCL2, THBS2, COL1A2, MMP9, and CXCL8. Another cohort was used for validation. Finally, analysis of the miRNAs identified potential therapeutic targets. The MR results suggested that although there was no causal relationship between IBD and NAFLD, there were causal relationships between IL-17 and IBD and NAFLD., Conclusion: We established a comorbid model to explain the potential mechanism of IBD with NAFLD and identified the chemokine-related pathway mediated by cytokine IL-17 as the core pathway in IBD with NAFLD, in which miRNA also plays a role and thus provides potential therapeutic targets., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Wei and Wang.)