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人口学视野下APC方法的困境及解决策略——以中国老年人口健康研究为例
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作者 秋丽雅 李建新 《人口与经济》 北大核心 2026年第1期91-105,共15页
老年健康研究与年龄、时期、队列等时间因素息息相关,这三个时间因素共同构成了社会科学研究的基本理论模型。人口学的列克西斯图为实现该理论模型提供了基本解析思路,而后来发展出来的APC三维分析模型实现了该理论模型的统计方法尝试,... 老年健康研究与年龄、时期、队列等时间因素息息相关,这三个时间因素共同构成了社会科学研究的基本理论模型。人口学的列克西斯图为实现该理论模型提供了基本解析思路,而后来发展出来的APC三维分析模型实现了该理论模型的统计方法尝试,虽然具体模型存在“天然缺陷”,但其试图从统计技术和概念上解决“识别问题”。以HAPC模型为例,提出合理应用APC三维分析模型应该重视队列分组依据,以理论驱动分组,明确结论适用范围。遵循上述步骤,分析中国老年人口健康的社会分化与演变,通过HAPC模型描绘不同出生队列的真实年龄效应。研究发现:教育和经济带来的中国老年人健康的社会分化稳健且持久,贯穿了不同年龄和出生队列;中国老年人健康的社会分层演变存在年龄效应和出生队列效应,累计优势/劣势理论、死亡选择性和病态状态扩展假设都无法单独解释老年人健康社会分化的演变。未来APC三维分析模型研究可能在范式转变、队列内轨迹细化、数据使用等方面获得突破。 展开更多
关键词 apc模型 出生队列分组 老年健康 生长曲线模型 列克西斯图
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The triglyceride-glucose index shows promise as a novel prognostic marker for advanced hepatocellular carcinoma
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作者 Tao Xu Xu Qi +1 位作者 Fei-Yu Zhao Nian-Song Qian 《World Journal of Gastroenterology》 2026年第2期167-169,共3页
This commentary critically appraises the study by Li et al which pioneered the exploration of the triglyceride-glucose(TyG)index as a prognostic marker in hepatitis B virus-related advanced hepatocellular carcinoma pa... This commentary critically appraises the study by Li et al which pioneered the exploration of the triglyceride-glucose(TyG)index as a prognostic marker in hepatitis B virus-related advanced hepatocellular carcinoma patients undergoing combined camrelizumab and lenvatinib therapy.While we acknowledge the study’s clinical relevance in proposing an easily accessible metabolic biomarker,we delve into the mechanistic plausibility linking insulin resistance to immunotherapy response and angiogenic inhibition.We further critically examine the methodological limitations,including the retrospective design,the populationspecific TyG cut-off value,and unaddressed metabolic confounders.We highlight the imperative for future research to validate its utility across diverse etiologies and treatment settings,and to unravel the underlying immunometabolic pathways. 展开更多
关键词 Triglyceride-glucose index Prognostic marker advanced hepatocellular carcinoma Camrelizumab Lenvatinib
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Advanced Design for High-Performance and AI Chips
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作者 Ying Cao Yuejiao Chen +2 位作者 Xi Fan Hong Fu Bingang Xu 《Nano-Micro Letters》 2026年第1期306-336,共31页
Recent years have witnessed transformative changes brought about by artificial intelligence(AI)techniques with billions of parameters for the realization of high accuracy,proposing high demand for the advanced and AI ... Recent years have witnessed transformative changes brought about by artificial intelligence(AI)techniques with billions of parameters for the realization of high accuracy,proposing high demand for the advanced and AI chip to solve these AI tasks efficiently and powerfully.Rapid progress has been made in the field of advanced chips recently,such as the development of photonic computing,the advancement of the quantum processors,the boost of the biomimetic chips,and so on.Designs tactics of the advanced chips can be conducted with elaborated consideration of materials,algorithms,models,architectures,and so on.Though a few reviews present the development of the chips from their unique aspects,reviews in the view of the latest design for advanced and AI chips are few.Here,the newest development is systematically reviewed in the field of advanced chips.First,background and mechanisms are summarized,and subsequently most important considerations for co-design of the software and hardware are illustrated.Next,strategies are summed up to obtain advanced and AI chips with high excellent performance by taking the important information processing steps into consideration,after which the design thought for the advanced chips in the future is proposed.Finally,some perspectives are put forward. 展开更多
关键词 Artificial intelligence advanced chips AI chips Design tactics Review and perspective
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Candidate injector design for the Southern Advanced Photon Source based on linac and booster
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作者 Liang-Sheng Huang Yan-Liang Han +5 位作者 Wei-Hang Liu Jian-Liang Chen Sheng Wang Yi Jiao Xiao Li Jia-Xin Chen 《Nuclear Science and Techniques》 2026年第2期67-78,共12页
The Southern Advanced Photon Source(SAPS)is a diffraction-limited synchrotron light source under design,which employs longitudinal injection as its primary injection scheme.This kind of injection scheme requires that ... The Southern Advanced Photon Source(SAPS)is a diffraction-limited synchrotron light source under design,which employs longitudinal injection as its primary injection scheme.This kind of injection scheme requires that the injected beam has a short bunch length and low emittance,and the preferred injector should offer high stability and low cost.Therefore,an injector based on a booster synchrotron was developed.The proposed injector includes a 250 MeV linac,a booster synchrotron that ramps the beam energy to 3.5 GeV,and two beam transport lines to ensure efficient beam delivery and beam quality preservation.The linac utilizes a thermionic high-voltage DC gun for reliable operation and features a bunching system with an advanced focusing system to preserve the emittance.To meet the injection requirements of the SAPS,a comprehensive design for the booster has been conducted.The booster synchrotron employs a threefold lattice structure,incorporating modified theoretical minimum emittance cells with a small momentum compaction factor and a high voltage to achieve an emittance of 3.98 nm rad and a bunch length of 4.8 mm.The injector has the potential to deliver a high charge,reducing the injection period of the storage ring to less than 1 min.Simulations demonstrated the expected performance,with a transmission efficiency of 90%,confirming its capability to meet the injection requirement of the SAPS storage ring.This design offers a stable and efficient solution for the SAPS. 展开更多
关键词 Southern advanced Photon Source Longitudinal injection Booster synchrotron EMITTANCE Bunch length
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Prognostic Value of Neutrophil-to-Lymphocyte Ratio in Locally Advanced Rectal Cancer Treated with Neoadjuvant Concurrent Chemoradiotherapy and Robotic-Assisted Resection
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作者 Yen-Cheng Chen Tsung-Kun Chang +7 位作者 Wei-Chih Su Yung-Sung Yeh Po-Jung Chen Tzu-Chieh Yin Ching-Chun Li Ching-Wen Huang Hsiang-Lin Tsai Jaw-Yuan Wang 《Oncology Research》 2026年第3期486-501,共16页
Background:The long-term outcomes of robotic-assisted surgery and the prognostic significance of the pretreatment neutrophil-to-lymphocyte ratio(NLR)in locally advanced rectal cancer(LARC)remain uncertain.This study a... Background:The long-term outcomes of robotic-assisted surgery and the prognostic significance of the pretreatment neutrophil-to-lymphocyte ratio(NLR)in locally advanced rectal cancer(LARC)remain uncertain.This study aimed to assess the long-term outcomes of patients with LARC undergoing robotic-assisted surgery and to determine the prognostic value of pretreatment NLR.Methods:We retrospectively reviewed 252 patients with LARC who were treated at a single medical center in Taiwan between January 2012 and January 2023.All patients underwent neoadjuvant concurrent chemoradiotherapy(CRT)followed by robotic-assisted surgery with total mesorectal excision(TME).Patients were stratified into four groups on the basis of pretreatment NLRs and carcinoembryonic antigen(CEA)levels.Univariate and multivariate analyses were conducted to identify prognostic indicators for overall survival(OS)and disease-free survival(DFS).Results:Patients with a pretreatment NLR of≥3.2 exhibited significantly worse OS and DFS compared with those with an NLR of<3.2(OS:94.4 vs.116.5 months,p=0.001;DFS:78.8 vs.101.7 months,p=0.003).Group A exhibited the poorest prognosis,whereas Group D had the most favorable outcomes.Multivariate analysis revealed NLR≥3.2 as an independent predictor of poor OS(hazard ratio[HR]=2.306,95%CI:1.149-3.747;p=0.001)and DFS(HR=2.055,95%CI:1.341-3.148;p=0.001).Conclusion:Neoadjuvant concurrent CRT followed by robotic-assisted TME is an effective treatment strategy for LARC.A higher pretreatment NLR(≥3.2)independently predicted worse OS and DFS.Stratification using the NLR in combination with CEA levels may enhance prognostic accuracy for patients undergoing robotic-assisted surgery for LARC. 展开更多
关键词 Locally advanced rectal cancer neoadjuvant concurrent chemoradiotherapy robotic-assisted surgery neutrophil-to-lymphocyte ratio carcinoembryonic antigen
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Carved Connections:Merging artisanal skill,advanced manufacturing and cultural storytelling,Yunhe turns wooden toys into carriers of Chinese culture across the globe
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作者 LIU YOUMENG 《ChinAfrica》 2026年第2期46-48,共3页
Yunhe County in Lishui City,southwestern Zhejiang Province,doesn’t have any Disney castles.Instead,it has built bridges to the world with wood.Known as“China’s town of wooden toys,”accounting for about 40 percent ... Yunhe County in Lishui City,southwestern Zhejiang Province,doesn’t have any Disney castles.Instead,it has built bridges to the world with wood.Known as“China’s town of wooden toys,”accounting for about 40 percent of the global wooden toy market,Yunhe’s story began with a small factory established in 1970.Today,it has grown into a distinctive industrial cluster with an annual output value exceeding 8 billion yuan($1.15 billion),exporting products to 82 countries and regions. 展开更多
关键词 yunhe county advanced manufacturing carved connections artisanal skill wooden toy wooden toys accounting cultural storytelling lishui city
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Risk factors for paternal perinatal depression in Chinese advanced maternal age couples:A regression mixture model
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作者 Xing Yin Juan Du +1 位作者 Shao-Lian Cai Xing-Qiang Chen 《World Journal of Psychiatry》 2026年第1期267-277,共11页
BACKGROUND Paternal perinatal depression(PPD)is closely associated with maternal mental health challenges,marital strain,and adverse child developmental outcomes.Despite its significant impact,PPD remains under-recogn... BACKGROUND Paternal perinatal depression(PPD)is closely associated with maternal mental health challenges,marital strain,and adverse child developmental outcomes.Despite its significant impact,PPD remains under-recognized in family-centered clinical practice.Concurrently,against the backdrop of rising rates of delayed marriage and China’s Maternity Incentive Policy,the proportion of women giving birth at an advanced maternal age is increasing.Nevertheless,research specifically examining PPD among spouses of older mothers remains critically scarce,both in China and globally.AIM To investigate PPD and its influencing factors in Chinese advanced maternal age families.METHODS This cross-sectional study included 358 participants;it was conducted among fathers of pregnant women of advanced maternal age at five hospitals in the Pearl River Delta region of China from September 2023 to June 2024.Data were collected via a general information questionnaire,the Social Support Rating Scale,and the Edinburgh Postnatal Depression Scale.Latent profile analysis and regression mixture models(RMMs)were adopted to analyze the latent PPD types and factors that influenced PPD.RESULTS The incidence of PPD was 16.48%,and three profiles were identified:Low-symptomatic(175 cases,48.89%),monophasic(140 cases,39.10%),and high-symptomatic(43 cases,12.01%).The RMM analysis revealed that first pregnancy,low income(<¥3000/month),part-time work,and a history of abnormal pregnancy were positively associated with the high-symptomatic type(P<0.05).Conversely,high subjective support and support utilization were negatively associated with the high-symptomatic type compared with the low-symptomatic type(P<0.05).Good couple relationships,high objective and subjective support,and high support utilization were negatively associated with monophasic disorder(P<0.05).CONCLUSION PPD incidence is high among Chinese fathers with advanced maternal age partners,and the characteristics of depression are varied.Healthcare practitioners should prioritize individuals with low levels of social support. 展开更多
关键词 advanced maternal age Paternal perinatal depression Fathers’mental health Regression mixture model advanced-age pregnancy Latent profile analysis
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miR-449a:A Novel Biomarker for Diagnosis,Prognosis,and Treatment Response in Locally Advanced Laryngeal Squamous Cell Carcinoma
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作者 Amal F.Gharib Ohud Alsalmi +5 位作者 Hayaa M.Alhuthali Afaf Alharthi Saud Ayed Alharthi Shaimaa A.Alharthi Rasha L.Etewa Wael H.Elsawy 《Oncology Research》 2026年第3期558-574,共17页
Background:Locally advanced laryngeal squamous cell carcinoma(LA-LSCC)presents clinical challenges due to the lack of reliable non-invasive biomarkers.This study aimed to evaluate miR-449a as a diagnostic and prognost... Background:Locally advanced laryngeal squamous cell carcinoma(LA-LSCC)presents clinical challenges due to the lack of reliable non-invasive biomarkers.This study aimed to evaluate miR-449a as a diagnostic and prognostic biomarker in LA-LSCC.Methods:miR-449a expression was analyzed in tumor tissues,adjacent normal tissues,and serum from 81 LA-LSCC patients and 50 controls using quantitative real-time reverse transcription polymerase chain reaction(qRT-PCR).We assessed the diagnostic accuracy by Receiver Operating Characteristic curve(ROC curves),clinicopathological associations,survival outcomes(Kaplan-Meier),and treatment response dynamics.Results:miR-449a was significantly downregulated in LA-LSCC tissues(p<0.0001)and serum(p<0.0001),with a strong tissue-serum correlation(R^(2)=0.988).Tissue miR-449a demonstrated a diagnostic accuracy(Area Under the Curve,AUC=0.857),while serum showed moderate accuracy(AUC=0.734).High miR-449a expression correlated with favorable clinicopathological features and improved survival(median overall survival:67.82 vs.23.74 months;p=0.0012).Multivariate analysis confirmed miR-449a as an independent prognostic factor(p<0.001).miR-449a levels increased post-treatment,particularly in responders to chemotherapy/radiation(p<0.0001).Conclusion:miR-449a serves as a non-invasive biomarker for LA-LSCC diagnosis,prognosis,and treatment monitoring.Its dynamic expression highlights potential for risk stratification and therapy response prediction,warranting further validation in larger cohorts. 展开更多
关键词 Locally advanced laryngeal squamous cell carcinoma(LA-LSCC) microRNA-449a(miR-449a) BIOMARKER PROGNOSIS DIAGNOSIS treatment response serum biomarker CHEMORADIOTHERAPY organ preservation
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工业锅炉的基础控制优化及APC控制器应用 被引量:1
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作者 吴科学 吴赟盟 《工业锅炉》 2025年第4期50-53,58,共5页
采用先进过程控制(APC)实施控制性能优化,进而提高锅炉的自控率和控制精度,确保运行稳定性并降低能耗,经过对控制系统基础控制回路PID参数自适应优化,提升工业锅炉自动化水平,并对锅炉进行系统性控制性能优化,提升关键过程参数的控制品... 采用先进过程控制(APC)实施控制性能优化,进而提高锅炉的自控率和控制精度,确保运行稳定性并降低能耗,经过对控制系统基础控制回路PID参数自适应优化,提升工业锅炉自动化水平,并对锅炉进行系统性控制性能优化,提升关键过程参数的控制品质,提升燃煤效率并降低操作人员的劳动强度,从而提高锅炉装置的运行平稳性,节约生产运行成本。 展开更多
关键词 先进过程控制(apc) 锅炉控制性能优化 PID控制回路
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搭接长度等对Ⅱ型APC接头拉伸性能的影响
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作者 余琼 敖晟瑞 +4 位作者 唐子鸣 郭霖 谢青海 张志 陈振海 《哈尔滨工业大学学报》 EI CAS 北大核心 2025年第1期128-139,共12页
为研究搭接长度和钢筋直径对Ⅱ型APC接头力学性能的影响,对63个该接头进行单向拉伸试验,分析了接头破坏模式、极限承载力、延性和黏结应力等。结果表明:钢筋直径相同时,随搭接长度增加,平均黏结应力降低,试件强度、延性、最大力总伸长... 为研究搭接长度和钢筋直径对Ⅱ型APC接头力学性能的影响,对63个该接头进行单向拉伸试验,分析了接头破坏模式、极限承载力、延性和黏结应力等。结果表明:钢筋直径相同时,随搭接长度增加,平均黏结应力降低,试件强度、延性、最大力总伸长率明显提高,残余变形整体呈下降趋势;钢筋拉断破坏试件强度、延性、最大力总伸长率和残余变形满足规范要求;加载过程中,套筒中部截面短边纵向和长边环向始终受拉;极限荷载下,随搭接长度增加,套筒中部截面短边侧环向压应变先转变为拉应变再向压应变发展,长边侧纵向压应变转变为拉应变;相对搭接长度相同时,极限承载力随钢筋直径增加而提高;提出的极限黏结强度及临界搭接长度计算公式与试验值吻合较好,可为实际工程应用提供参考。单拉工况下,钢筋直径不大于18 mm时,建议接头搭接长度大于12 d。 展开更多
关键词 Ⅱ型apc接头 拉伸性能 搭接长度 黏结强度
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APC接头连接的T型全预制剪力墙抗震试验
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作者 余琼 袁越 +3 位作者 程浩 唐子鸣 郭霖 谢青海 《哈尔滨工业大学学报》 北大核心 2025年第5期100-113,共14页
为研究套筒灌浆搭接接头(简称APC接头)连接的T型全预制剪力墙的抗震性能,在Ⅰ、Ⅱ型APC接头的基础上,对1片现浇墙和2片预制墙进行拟静力试验。结果表明:现浇墙初始水平裂缝出现在基础顶面,由于套筒对混凝土的约束,预制墙的初始水平裂缝... 为研究套筒灌浆搭接接头(简称APC接头)连接的T型全预制剪力墙的抗震性能,在Ⅰ、Ⅱ型APC接头的基础上,对1片现浇墙和2片预制墙进行拟静力试验。结果表明:现浇墙初始水平裂缝出现在基础顶面,由于套筒对混凝土的约束,预制墙的初始水平裂缝出现在套筒上方;极限状态下,试件均为弯剪破坏,现浇墙墙脚边缘混凝土压碎、钢筋压屈,预制墙为套筒上方钢筋压屈、混凝土压碎、套筒外混凝土剥落;在开裂、屈服、峰值荷载,刚度、延性和耗能能力方面,采用Ⅰ型套筒的预制墙与现浇墙相当,而采用Ⅱ型套筒的预制墙大于现浇墙;两种套筒在预制剪力墙的受力过程中保持弹性状态,均能有效传递钢筋应力;预制试件平面外位移在加载过程中出现负向累积,但相同加载级时预制墙与现浇墙平面外位移绝对值相当。 展开更多
关键词 T型全预制剪力墙 套筒灌浆搭接接头 搭接连接 拟静力试验 抗震性能
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基于APCS-MLR受体模型的江西省宜丰县土壤重金属来源解析及生态风险评价 被引量:3
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作者 唐志敏 周墨 +6 位作者 张明 张晓东 田福金 刘冰权 周强强 文帮勇 姜宏裕 《环境科学》 北大核心 2025年第7期4674-4683,共10页
土壤中重金属的富集是自然过程和人为活动共同作用的结果,开展土壤重金属来源解析及生态风险评价是服务土壤重金属污染防治的必要手段.为查明江西省宜丰县土壤中重金属来源及其生态风险特征,采集分析了宜丰县表层土壤中重金属含量以及p... 土壤中重金属的富集是自然过程和人为活动共同作用的结果,开展土壤重金属来源解析及生态风险评价是服务土壤重金属污染防治的必要手段.为查明江西省宜丰县土壤中重金属来源及其生态风险特征,采集分析了宜丰县表层土壤中重金属含量以及pH值等指标,采用绝对主成分得分-多元线性回归(APCS-MLR)受体模型解析了土壤中重金属来源并定量计算了各来源贡献率,基于地累积指数法和潜在生态风险指数法对土壤重金属生态风险进行了评价,同时采用GIS技术对土壤重金属的空间分布规律进行了探讨.结果显示,宜丰县土壤中ω(As)、ω(Cd)、ω(Cr)、ω(Cu)、ω(Hg)、ω(Ni)、ω(Pb)和ω(Zn)的平均值分别为9.7、0.211、68、25、0.113、24、37和87 mg·kg^(−1),均高于江西省土壤背景值.受地质背景控制,土壤As、Cr、Cu和Ni的高含量区与区内青白口系变质岩建造的分布相吻合,受人为活动干扰,Cd、Hg、Pb和Zn的空间分布与岩石建造类型分布呈现显著差异.生态风险评价发现宜丰县土壤重金属污染风险总体较低,但局部存在以As、Cd和Hg为主的轻微污染和中等风险.APCS-MLR受体模型解析出了3个重金属来源:As、Cr、Cu和Ni主要为自然来源,贡献率分别为80.06%、69.92%、80.49%和94.27%,Pb和Zn主要为交通来源,贡献率分别为74.73%和66.99%,Cd和Hg主要受工农业来源的控制,贡献率分别为43.62%和58.09%.研究结果可为宜丰县土壤污染防治提供数据理论支撑. 展开更多
关键词 土壤 重金属 来源 apcS-MLR受体模型 生态风险
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APCS-MLR结合PMF模型解析大气PM_(2.5)中重金属元素来源及健康风险 被引量:3
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作者 彭家美 于瑞莲 +2 位作者 胡恭任 陈衍婷 吴雅清 《环境科学》 北大核心 2025年第11期7371-7384,共14页
为探究江西省南康市大气PM_(2.5)中重金属的污染特征、来源及健康风险,对该地区4个季节的大气PM_(2.5)进行采样,用ICP-MS分析测定11种重金属元素(Cu、Fe、Zn、Mn、Cd、Co、As、Ba、Pb、Cr和Ti)的含量,分析了Cu、Fe、Zn、Mn、Cd、Co、As... 为探究江西省南康市大气PM_(2.5)中重金属的污染特征、来源及健康风险,对该地区4个季节的大气PM_(2.5)进行采样,用ICP-MS分析测定11种重金属元素(Cu、Fe、Zn、Mn、Cd、Co、As、Ba、Pb、Cr和Ti)的含量,分析了Cu、Fe、Zn、Mn、Cd、Co、As、Ba和Pb的污染特征.结合富集因子分析、多变量分析方法(最大方差旋转因子分析)、APCS-MLR(绝对主成分线性回归)和PMF(正定矩阵因子分解)模型定量解析大气PM_(2.5)中重金属来源,并对重金属元素的人体健康风险进行评价.结果表明,采样期间研究区ρ(PM_(2.5))平均值为46.98μg·m^(-3),超过国家环境空气质量二级标准,且PM_(2.5)质量浓度在冬季最高.PM_(2.5)中9种重金属浓度年平均值高低依次为:Fe>Zn>Pb>As>Mn>Cu>Ba>Cd>Co.富集因子分析结果显示,研究区大气PM_(2.5)中大部分金属元素含量超过了江西省A层土壤环境背景值,除Fe和Ba外,其余重金属在环境中均相对富集,且受人类活动影响较大.因子分析表明,研究区大气PM_(2.5)的重金属污染源主要有4类:机动车源、工业源、燃煤源和自然源,Mn、Cu和Zn主要来源为机动车排放源,Co主要来源于以家具厂为代表的工业源,As、Cd和Pb主要来源于燃煤,Fe和Ba以自然源为主.APCS-MLR和PMF模型分析结果表明,由人类活动所引起的污染来源(机动车源、工业源和燃煤源)具有更高的贡献率,其中的燃煤源,在两个模型中的贡献率为20%~40%.健康风险分析结果显示,9种重金属均不存在非致癌风险,As和Mn对3类人群均存在潜在致癌风险,且对成年男性的致癌风险最大. 展开更多
关键词 PM_(2.5) 重金属 富集因子 绝对主成分线性回归(apcS-MLR) 正定矩阵因子分解(PMF) 健康风险
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基于PMF和APCS-MLR模型的会仙湿地沉积物重金属源解析及污染风险评价 被引量:2
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作者 刘涛 沈利娜 +1 位作者 于奭 秦金福 《环境科学》 北大核心 2025年第9期6024-6036,共13页
基于会仙湿地14个点位沉积物样品测试分析结果,探讨(Cu、Pb、Cd、Cr、Zn、Ni、Hg和As)8种重金属的含量特征,并运用地累积指数法和潜在生态风险指数对重金属进行风险评估,结合相关性分析、聚类分析、绝对主成分-多元线性回归(APCS-MLR)... 基于会仙湿地14个点位沉积物样品测试分析结果,探讨(Cu、Pb、Cd、Cr、Zn、Ni、Hg和As)8种重金属的含量特征,并运用地累积指数法和潜在生态风险指数对重金属进行风险评估,结合相关性分析、聚类分析、绝对主成分-多元线性回归(APCS-MLR)和正定矩阵因子分解(PMF)等多种方法,识别和定量解析污染源及贡献.结果表明:①8种重金属的平均含量均高于背景值,其中Cd超过《土壤环境质量-农用地土壤污染风险管控标准》(GB 15618-2018)筛选值.②地累积指数评价结果表明,Cd属于中度污染,Zn属于偏中度污染,Hg、Ni、Cr和Pb属于轻度污染,As和Cu属于无污染.③潜在风险指数评价结果表明,Cd(245.91)属于很强生态风险,Hg(134.59)属于强生态风险,其它元素均属于轻微生态风险;研究区综合生态风险指数均值为433.33,整体呈现出强的潜在生态风险.④APCS-MLR识别出4个污染源,分别为农业源、自然与农业源、大气沉降与生活源和未识别源(交通与农业源),贡献率分别为33.16%、15.75%、9.50%和41.59%;PMF识别出3个污染源,分别为大气沉降与生活源、自然与农业源和交通与农业源,贡献率分别为21.92%、35.24%和42.84%. 展开更多
关键词 沉积物 重金属 源解析 正定矩阵因子分解(PMF) 绝对主成分-多元线性回归(apcS-MLR)
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茶树APC/C基因家族全基因组鉴定及表达模式分析
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作者 李红建 王青 +7 位作者 方开星 倪尔冬 姜晓辉 秦丹丹 王秋霜 潘晨东 李波 吴华玲 《江苏农业科学》 北大核心 2025年第19期52-61,共10页
APC/C是一类多亚基E3泛素连接酶,在植物生长发育和逆境反应中起着重要作用。为研究茶树APC/C基因家族的特征,探讨其功能和在逆境适应中的潜在作用,利用生物信息学方法从茶树基因组中鉴定到15个APC/C基因,分析其染色体定位、基因结构、... APC/C是一类多亚基E3泛素连接酶,在植物生长发育和逆境反应中起着重要作用。为研究茶树APC/C基因家族的特征,探讨其功能和在逆境适应中的潜在作用,利用生物信息学方法从茶树基因组中鉴定到15个APC/C基因,分析其染色体定位、基因结构、保守结构域及进化关系;基于转录组数据分析各成员组织表达特异性及在非生物胁迫、激素处理下的响应模式。结果表明,15个APC/C基因家族成员不均匀地分布在6条染色体上;其蛋白长度为65~1 786 aa,分子量介于7.34~197.42 ku之间,等电点介于3.73~9.49之间。共线性分析结果显示,茶树APC/C基因家族成员与玫瑰同源基因亲缘关系较近,有7对基因存在共线性关系。启动子分析发现,茶树APC/C基因启动子中含有光响应元件最多。miRNA靶向预测显示,8个APC/C基因受16个miRNA靶向调控。表达模式分析结果显示,多数APC/C基因在茎和叶中表达量较高,且随着叶片成熟度增加表达量逐渐降低;APC/C基因在非生物胁迫和激素处理下呈现不同的响应模式。 展开更多
关键词 茶树 apc/C基因家族 非生物胁迫 激素响应 表达模式
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基于APCS-MLR模型的农用地土壤重金属污染溯源研究进展 被引量:1
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作者 于澍 李剑炜 +3 位作者 吕星浩 万大娟 袁腾跃 吴珏 《绿色科技》 2025年第8期139-145,共7页
我国农用地土壤重金属污染形势严峻,对生态环境和粮食安全构成重大威胁,准确解析污染来源是防控污染的关键前提。系统综述了APCS-MLR模型的农用地土壤重金属污染溯源应用及其进展。该模型在农用地土壤重金属溯源研究中,能有效识别主要... 我国农用地土壤重金属污染形势严峻,对生态环境和粮食安全构成重大威胁,准确解析污染来源是防控污染的关键前提。系统综述了APCS-MLR模型的农用地土壤重金属污染溯源应用及其进展。该模型在农用地土壤重金属溯源研究中,能有效识别主要污染源,并定量评估其对重金属元素的贡献。此外,APCS-MLR模型与PMF模型、地理信息系统及机器学习等技术的联合应用,进一步提升了重金属污染溯源的精度与空间可视化能力。尽管该模型在动态污染过程及小尺度解析中存在局限,但通过算法优化和多技术融合,其在农用地污染分区管控、生态修复评估及政策制定中具有广阔前景。未来需结合同位素示踪、高分辨率遥感等技术,推动APCS-MLR模型在精准农业环境管理中的应用,为保障土壤健康与粮食安全提供科学支撑。 展开更多
关键词 农用地 土壤重金属 溯源研究 apcS-MLR模型 研究进展
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基于APCS-MLR和PMF模型的石煤矿区及周边区域农田土壤重金属污染来源解析 被引量:5
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作者 董天浩 潘淑芳 +4 位作者 张仁杰 姜立恒 郭焱 纪雄辉 谢运河 《环境科学》 北大核心 2025年第5期3209-3219,共11页
为了探究石煤开采带来的农田土壤重金属污染风险,对某石煤矿区及周边区域农田土壤进行了采样分析及污染源解析.结果表明:①该石煤矿区及周边农田土壤重金属污染风险很高.按内梅罗综合污染指数确定的轻污染风险以上的采样点占比为61.6%,... 为了探究石煤开采带来的农田土壤重金属污染风险,对某石煤矿区及周边区域农田土壤进行了采样分析及污染源解析.结果表明:①该石煤矿区及周边农田土壤重金属污染风险很高.按内梅罗综合污染指数确定的轻污染风险以上的采样点占比为61.6%,其中重污染风险采样点占比达21.9%.研究区土壤Cd污染很严重,超出风险筛选值和风险管制值的采样点占比分别为71.5%和18.5%.②土壤Cd、Zn、Ni、Cu和As之间,As、Hg和Pb之间,Cr与As和Ni,Hg与Zn、Ni和Cu,均存在极显著正相关关系.Cd与Cr和Pb的相关性均不显著,其余重金属元素组合均存在显著正相关关系.③基于不同受体模型对研究区进行土壤重金属污染来源解析,识别出3个污染来源,即石煤开采源,大气沉降源和自然源.APCS-MLR模型判定土壤Cd、As、Cu、Zn和Ni主要受石煤开采源影响,Pb和Hg主要受大气沉降源影响,Cr主要受自然源影响;3个污染源的贡献率依次为43.2%、31.5%和25.3%.PMF模型的源解析结果与之总体上相同,但判定土壤Cd和Hg均受石煤开采-大气沉降混合源影响;3个污染源的贡献率依次为45.0%、34.5%和20.5%.研究表明,石煤矿区及周边区域农田土壤有较大的重金属污染风险,联合使用两种受体模型能够更合理地判别各土壤重金属主要的污染来源. 展开更多
关键词 土壤重金属 石煤 源解析 apcS-MLR模型 PMF模型
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中国劳动者失业风险感知变迁——基于APC模型的动态分析
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作者 吕风光 张顺 《人口与经济》 北大核心 2025年第6期44-58,共15页
劳动者的失业风险感知是客观就业处境的主观映射及预测指标。结合多重变迁趋势理论构建动态分析框架,基于2013—2021年中国社会状况综合调查(CSS)数据,使用“年龄-时期-世代”(APC)模型分解劳动者失业风险感知的年龄、时期和世代效应,... 劳动者的失业风险感知是客观就业处境的主观映射及预测指标。结合多重变迁趋势理论构建动态分析框架,基于2013—2021年中国社会状况综合调查(CSS)数据,使用“年龄-时期-世代”(APC)模型分解劳动者失业风险感知的年龄、时期和世代效应,得到以下核心结论:第一,在年龄效应上,失业风险感知随着年龄增长而下降,且下降趋势集中于劳动者就业初期;进一步分析发现,专用性人力资本和社会资本累积是失业风险感知在就业初期大幅下降的重要因素。第二,在时期效应上,2013—2021年失业风险感知逐年上升,这一趋势主要由数字经济推动就业形态快速变化所致,而劳动力成本上升和国际贸易形势的相对贡献较小。第三,在世代效应上,1960年左右世代群体的失业风险感知较低,而1975—1985年世代群体相对偏高;原因在于,1960年左右世代在就业初期失业率低,同辈竞争压力低,且劳动力素质与产业结构相匹配,因而具有较低的失业风险感知,而1975—1985年世代群体在就业初期失业率偏高,劳动力素质与产业结构出现分离,造成结构性失业与较高的失业风险感知。以上发现为治理失业风险提供了实证依据,对实现新时代高质量充分就业具有重要政策意义。 展开更多
关键词 失业风险感知 高质量充分就业 apc模型 劳动力
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The Coupling Relationship Between Industrial Linkage and Spatial Coagglomeration of Advanced Manufacturing and Producer Services in Metropolitan: A Case Study of Beijing, China 被引量:2
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作者 XU Xin SHEN Yuming +1 位作者 LIU Hanchu QIU Ling 《Chinese Geographical Science》 2025年第3期631-646,共16页
Promoting the deep integration of advanced manufacturing and producer services is not only a key path for metropolitan to climb the global value chain,but also an important new driving force for optimizing urban spati... Promoting the deep integration of advanced manufacturing and producer services is not only a key path for metropolitan to climb the global value chain,but also an important new driving force for optimizing urban spatial structure.Based on the two dimen-sions of industrial linkage and spatial co-agglomeration from the perspective of industrial integration,taking Beijing,China as a case,using industrial input-output data,micro-enterprise spatial data,and methods such as industrial linkage model,standard deviation el-lipse,and spatial similarity coefficient,this study explores the coupling relationship between industrial linkage and spatial co-agglomer-ation of advanced manufacturing and producer services from 2007 to 2020.The results demonstrate that:1)the industrial linkage between advanced manufacturing and producer services in Beijing has an upward trend,in which the business services have the most significant improvement,in which the business services have the most improvement while the technology services have the most de-crease,but in general,the industrial linkage between the two industries shows a low level.2)Producer services were more spatially clustered than advanced manufacturing,and the degree of spatial co-agglomeration of the two also showed an increasing trend,with strong regional and industrial heterogeneity characteristics,among which the pairing industry involving commerce services and techno-logy services had a more obvious improvement.3)The coupling analysis found that the spatial dependence between advanced manufac-turing and producer services decreased,showing a weak positive correlation and a decreasing trend between industrial linkage and spa-tial co-agglomeration;the heterogeneity among subdivision pairs is prominent,and the strong correlation between industries does not mean that there is an inevitable spatial co-agglomeration.4)Based on the differences in coupling relationships and influence mechan-isms,four coupling modes are identified:H-H type,H-L type,L-L type,and L-H type.Finally,this study proposes three policy implica-tions for the integration of advanced manufacturing and producer services in metropolitan areas. 展开更多
关键词 advanced manufacturing producer services industrial linkage spatial co-agglomeration Beijing China
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Lignin-derived carbon fibers:A green path from biomass to advanced materials 被引量:1
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作者 Li Yan Hai Liu +2 位作者 Yanfan Yang Lin Dai Chuanling Si 《Carbon Energy》 2025年第3期11-33,共23页
Carbon fibers(CFs)with notable comprehensive properties,such as light weight,high specific strength,and stiffness,have garnered considerable interest in both academic and industrial fields due to their diverse and adv... Carbon fibers(CFs)with notable comprehensive properties,such as light weight,high specific strength,and stiffness,have garnered considerable interest in both academic and industrial fields due to their diverse and advanced applications.However,the commonly utilized precursors,such as polyacrylonitrile and pitch,exhibit a lack of environmental sustainability,and their costs are heavily reliant on fluctuating petroleum prices.To meet the substantial market demand for CFs,significant efforts have been made to develop cost-effective and sustainable CFs derived from biomass.Lignin,the most abundant polyphenolic compound in nature,is emerging as a promising precursor which is well-suited for the production of CFs due to its renewable nature,low cost,high carbon content,and aromatic structures.Nevertheless,the majority of lignin raw materials are currently derived from pulping and biorefining industrial by-products,which are diverse and heterogeneous in nature,restricting the industrialization of lignin-derived CFs.This review classifies fossil-derived and biomass-derived CFs,starting from the sources and chemical structures of raw lignin,and outlines the preparation methods linked to the performance of lignin-derived CFs.A comprehensive discussion is presented on the relationship between the structural characteristics of lignin,spinning preparation,and structure-morphology-property of ligninderived CFs.Additionally,the potential applications of these materials in various domains,including energy,catalysis,composites,and other advanced products,are also described with the objective of spotlighting the unique merits of lignin.Finally,the current challenges faced and future prospects for the advancement of lignin-derived CFs are proposed. 展开更多
关键词 advanced materials carbon fibers chemical structure LIGNIN VALORIZATION
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