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Road traffic accidents occur frequently and have significant impacts on life, property, and society. However, existing researches on road traffic accident risk pay little attention on establishing an effective road network model that accurately describes the transmission characteristics of traffic accident risk. As a result, the accuracy of risk evaluation is limited. To address this issue, we propose a network geographically weighted regression method based on arrival time cost. We conduct experiments using data from roads, traffic violations, traffic accidents, and urban points of interest (POIs) in a city from 2018 to 2020. The experimental results demonstrate that the network geographically weighted regression method, based on arrival time cost, incorporates the propagation nature of traffic accident risk on the road. It significantly reduces evaluation errors and effectively evaluates road traffic accident risk and its influencing factors. The downtown area of the city exhibits high accident risk, primarily concentrated at intersections with heavy traffic flow and certain road points with inadequate transportation facilities. The impact of different types of road traffic violations and urban POIs on the risk of road traffic accidents varies significantly and exhibits strong spatial heterogeneity.(道路交通事故频发，给生命财产造成重大损失，给社会生活带来重大影响。现有针对道路交通事故风险的研究未建立有效的道路网络模型，难以准确描述交通事故风险在道路上的传播特点，评估准确度不高。基于此，提出了一种基于抵达时间成本的网络地理加权回归方法，并利用某县级市2018—2020年的道路、交通违法、交通事故、城市POI等数据开展实验，结果表明，基于抵达时间成本的网络地理加权回归方法融合了交通事故风险在道路上的传播性质，显著降低了评估误差，能够有效评估道路交通事故风险及其影响因素；市中心区域道路交通事故高风险区域主要集中在车流量较大的道路交会处与部分交通设施尚不完备的道路；各类交通违法数量、城市POI对道路交通事故风险的影响程度不同，且具有很强的空间异质性。)

配电网优化问题经常涉及运行约束。运行约束通常包含潮流方程这种非线性等式约束，在优化问题中较难处理。基于数学优化思想的处理方式是将潮流方程进行凸松弛或基于某些假设进行线性处理，可能导致求解速度慢、甚至得到的解不可行的问题。鉴于此，提出了基于数据拟合的配电网线性运行约束建模方法。首先，利用大量仿真数据进行线性拟合，建立了线性潮流模型及其他相关运行约束模型。然后，将其应用于配电网优化运行问题和故障恢复问题，分别将两个问题建模为线性规划模型（fitting-linear program,F-LP）和混合整数线性规划模型（fitting-mixed integer linear program,F-MILP）。最后，在修改后的IEEE 13、34、37和123节点算例中验证了该线性近似运行约束的有效性和优越性。

配电网中本地可控发电资源能量有限，光伏和风电等可再生能源发电（variable renewable energy-distributed generation,VRE-DG）在天气条件良好时出力可观，可为大电网停电事故后配电网应急供电恢复提供有力支撑。然而，失去大电网支撑的电气孤岛抗扰动能力弱，而VRE-DG出力具有不确定性，如处理不当则会造成功率失衡甚至恢复失败。计及VRE-DG的配电网应急供电恢复策略，通过在每个时段初期求解多时段恢复模型和优化运行模型确定该时段的恢复策略和最优运行状态。算例表明，该策略可最小化VREDG出力不确定性带来的风险，充分利用VRE-DG对重要负荷供电。

电动汽车作为分布式移动储能单元，可以在极端事件发生后调度至充电站，作为应急电源为配电网内关键负荷恢复供电，从而提升配电网韧性。因此在充电站布点规划阶段需要考虑电动汽车在提升配电网韧性方面的作用。重点关注可调度类电动汽车的充电站布点方法，以配电网各个极端场景下关键负荷加权恢复数目最大、电压幅值差最小以及交通网充电距离最小为目标，综合考虑充电站数目约束、配电网运行约束和充电站输出功率等约束，提出了一种兼顾配电网韧性和充电便利性的充电站布点问题的混合整数线性规划模型，可利用成熟优化求解器有效求解。最后通过算例分析验证了提出的充电站布点方法的有效性。

为了提升可见光通信（VLC）定位系统的频谱和功率利用率,文章提出了一种基于非对称限幅和直流偏置的光正交频分复用（ADO-OFDM）的VLC定位集成系统。该通信定位集成系统具有比基于非对称限幅的光正交频分复用（ACO-OFDM）的VLC定位集成系统更高的频谱利用率和比基于加直流偏置的光正交频分复用（DCO-OFDM）的VLC定位集成系统更高的功率利用率。同时,文章还提出了一种差分修正定位算法,所提算法较于传统的三边定位算法其具有更高的定位精度。

电力骨干通信网中告警信息的及时高效处理能够为故障处置提供先机。利用人工智能技术,基于历史数据可以预测告警的发生,完备的数据集是成功实现预测的基本条件。在现实网络中采集的数据往往有分布不均匀、数据缺失等问题,如何构建完备的数据集是基于人工智能技术实现电力骨干通信网中告警预测的一个关键问题。文章提出了一种针对电力骨干通信网中告警预测的数据预处理方法,采用数据增强技术完成了数据的类均衡,使得最终的数据集符合模型输入的数据尺寸。仿真结果表明,基于数据增强的告警预测数据预处理方法能够在较大程度上提高告警预测的准确率。

研究了基于OFDM（正交频分复用）的电力线与可见光融合通信系统中的信道估计技术,通过建立电力线与可见光信道模型,研究了梳状和块状导频结构下的LS（最小二乘）与SVD（奇异值分解）两种估计准则,以及线性插值与基于DFT（离散傅里叶变换）的插值两种内插方法,通过比较发现,块状导频下的SVD结合线性插值是性能较佳的信道估计算法,并且该算法对导频间隔不敏感。

研究了基于DWT（小波变换）的OFDM（正交频分复用）和FFT（快速傅里叶变换）的OFDM两种不同调制方式在PLC（电力线通信）系统中的性能。首先建立了两种不同调制方式下PLC的系统模型,然后在AWGN（加性高斯白噪声）和子CFO（载波频率偏移）的干扰下,分析了两种系统的误码性能以及峰均功率比的分布。通过仿真发现,在PLC系统中,DWT-OFDM系统比FFT-OFDM系统更具优势,在未来的PLC系统中必将发挥重要的作用。

针对可见光通信系统调制带宽有限的问题,提出了将两种具有高频带利用率的调制方式应用于可见光通信系统的方案。分别论述了正交频分复用和奈奎斯特单载波调制的基本原理和产生途径,仿真验证了正交频分复用和奈奎斯特单载波两种调制解调技术应用于可见光通信系统时的性能,比较分析了两种技术在不同信噪比条件下的误码率和频带利用率,仿真结果表明,奈奎斯特单载波相对于正交频分复用有更高的频带利用率和较低的误码率,更适用于可见光通信系统。

针对发光二极管之间的多径干扰,提出了采用QR分解的信道均衡算法消除干扰的方案。首先建立基于离散傅里叶变换扩频的正交频分复用技术的电力线与可见光融合通信系统,并考虑了由两个发光二极管之间的电线差所引发的多径干扰,然后比较了该系统下采用QR分解的信道均衡算法和传统信道均衡算法下的误码性能。结果表明,采用QR分解的信道均衡算法可消除由发光二极管之间的电线差引起的多径干扰,从而提高系统的传输性能。

为了实现每基杆塔的光纤定位,从而更精准地实时监测光纤架空地线复合缆的运行状态,提出了一种基于分布式光纤传感技术的杆塔光纤定位方法。通过对实时监测频移数据进行分析,并结合光纤架空地线复合缆自身结构和架设特点发现,在杆塔连接位置由于金具等的连接原因,使得光纤频移变化量较档距中间更小,因而可以从差异化出发识别杆塔的位置,实现输电线路杆塔精确定位。最后通过与线路资料进行对比,验证了定位方式的可行性。

Objective To explore the molecular mechanisms and cell-cell interactions in the injury process of pancreatic islet transplantation. Methods Single-cell transcriptome data from mouse islets treated with inflammatory factors were used, and data processing was performed using the Seurat package, with integrated data to remove batch effects. Cell subpopulations were annotated based on known markers. Cell-cell interactions in the inflammatory factor-treated group were analyzed using the CellChat package, and inferred based on the expression of cell surface receptors and ligands. Gene set enrichment analysis was used to clarify the biological processes enriched in β-cells after treatment with inflammatory factors. Finally, differentially expressed transcription factors were identified and verified using microarray datasets of donor islet ischemic injury and Western blotting. Results A total of 7 different cell subpopulations were found in mouse islets, with β-cells being the most abundant. Cell-cell interaction network analysis showed that the number and strength of interactions between ductal cells and other cells were the highest. Gene set enrichment analysis showed that after treatment with inflammatory factors, the immune response was positively enriched in β-cells, while peptide hormone metabolism, bile acid metabolism, and ion homeostasis were downregulated. The common differential transcription factors identified in the mouse single-cell transcriptome and the microarray dataset of donor islet ischemic injury were early growth response 1 (EGR1), nuclear factor-κB inhibitor α (NFKBIA), and activating transcription factor 3 (ATF3). Among them, NFKBIA and ATF3 were upregulated, while EGR1 was downregulated. The expression of EGR1 protein was downregulated after 24 h, 48 h, and 72 h of cold ischemia. Conclusions EGR1 is a transcription factor closely related to islet cold ischemia, and future research should focus on the specific mechanisms of EGR1 and its downstream target genes, in order to provide more effective strategies for clinical treatment of islet transplantation. [ABSTRACT FROM AUTHOR]

Copyright of Modern Preventive Medicine is the property of Modern Preventive Medicine Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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Copyright of China Condiment is the property of China Condiment and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Electric Power Automation Equipment / Dianli Zidonghua Shebei is the property of Electric Power Automation Equipment Press and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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Copyright of Shandong Medical Journal is the property of Shandong Medical Health Newspapers and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This article takes Ningxia as the research object, analyzes the current situation of comprehensive grain production capacity in Ningxia, and uses the grey correlation analysis method to explore the problems faced by comprehensive grain production in Ningxia and the factors affecting the comprehensive grain production capacity.The results showed that: ①The overall comprehensive grain production capacity is on the rise, but the problem of regional grain crop structure imbalance is more prominent.There are problems such as reduced arable land planting area, labor loss, and insufficient scientific and technological talents. ②The top three main factors affecting the comprehensive grain production capacity of Ningxia are the net amount of unit fertilizer application, rural electricity consumption, and rural employees, with correlation degrees of 0.897, 0.763, and 0.758, respectively. The results of this study lay a theoretical foundation for future research on the construction of comprehensive grain production capacity in Ningxia, which is conducive to promoting the construction of comprehensive grain production capacity in Ningxia. [ABSTRACT FROM AUTHOR]

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Copyright of Biology Teaching is the property of East China Normal University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Progress in Modern Biomedicine is the property of Publishing House of Progress in Modern Biomedicine and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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Copyright of Shandong Medical Journal is the property of Shandong Medical Health Newspapers and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective To investigate disease characteristics and hospitalization costs of children with Mycoplasma Pneumoniae pneumonia (MPP) admitted to Shanghai municipal medical hospitals from 2019 to 2023. Methods Depending on the Shanghai Municipal Hospital Pediatric Alliance, we retrospectively investigated community acquired MPP pediatric patients hospitalized in 22 municipal hospitals with pediatric qualifications (including 4 children’s hospitals) in Shanghai from Jan 2019 to Dec 2023. We collected the patients' diagnosis codes, gender, age, length of hospital stay, hospitalization costs, and whether they progressed to severe Mycoplasma pneumoniae pneumonia (SMPP). Results From 2019 to 2023, a total of 29 045 hospitalized children with MPP were treated, with 6 035 cases (20.8%) identified as SMPP in the 22 hospitals. Trend analysis revealed a rising trend with years in the proportion of SMPP patients (χ² trend=365.498, P<0.001). Among the 4 children's hospitals, there were 18 710 cases with MPP, including 4 078 cases (21.8%) of SMPP. The proportion of SMPP patients also showed an increasing trend with years (χ² trend=14.548, P<0.001), and the proportion in 2023 (23.0%) was higher than that in previous years with statistical significance. There were statistical differences in the seasonal distribution of MPP cases between different years, with higher proportions in summer and autumn overall. The age distribution of hospitalized MPP children varied among different years, with school-age children accounting for the majority (56.8%) in 2023. There was no difference in the distribution of severe cases between different genders, but there were differences in the proportion of severe cases among different age groups in different years, with a gradual increase in severe cases among children aged 1 to 3 years (χ² trend= 191.567, P<0.001). The average length of hospital stay for MPP during the epidemic was higher than that during non-epidemic periods, and there were statistically significant differences in the average length of hospital stay between different years (P<0.001). The individual hospitalization costs during the epidemic were higher than in other years, and there were statistically significant differences in individual hospitalization costs between different years (P<0.001). The total hospitalization costs were still higher in 2019 and 2023. The individual hospitalization costs for SMPP were higher than for non-SMPP cases. Conclusion MPP outbreaks occurred in Shanghai in 2019 and 2023, with the higher proportions in summer and autumn overall. Compared to previous years, the number of hospitalized MPP children in Shanghai was higher in 2023, with a higher proportion of SMPP cases, especially among children under 3 years old. The individual per capita hospitalization expenses for SMPP cases were higher than for nonSMPP cases. [ABSTRACT FROM AUTHOR]

Copyright of Current Biotechnology (2095-2341) is the property of Chinese Academy of Agricultural Sciences, Institute of Biotechnology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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Copyright of Journal of Chinese Institute of Food Science & Technology / Zhongguo Shipin Xuebao is the property of Journal of Chinese Institute of Food Science & Technology Periodical Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)