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Retrospective analysis of preoperative tumor marker levels in rectal cancer patients: Implications for diagnosis

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World Journal of Gastrointestinal Surgery 2025年第3期17卷 221-228页

作者： Ming Li Da-Hao Yuan Zhi Yang teng-Xiang Lu Lei Zhang Clinical Laboratory Linquan County People’s HospitalLinquan 236400Anhui ProvinceChina Hemodialysis Center Linquan County People’s HospitalLinquan 236400Anhui ProvinceChina Department of Gastrointestinal Surgery Linquan County People’s HospitalLinquan 236400Anhui ProvinceChina

BACKGROUND Early detection of rectal cancer poses significant *** diagnostic methods,including colonoscopy,imaging techniques,and fecal tests,have limitations such as invasiveness,cost,and varying *** study evaluated the diagnostic value of preoperative serum tumor markers in rectal cancer *** To investigate the value of a multi-marker approach for the preoperative diagnosis of rectal *** A retrospective analysis of 250 patients diagnosed with rectal cancer between July 2022 and July 2024 was *** alpha-fetoprotein levels,carcinoembryonic antigen(CEA),cancer antigen 125(CA125),CA19-9,CA15-3,and CA72-4 were *** blood samples were collected under standardized conditions,including fasting status and proper storage methods,within two weeks before *** performance was assessed using receiver operating characteristic curve *** among clinicopathological features were also *** CEA demonstrated the highest diagnostic performance among individual tumor markers with an area under the curve(AUC)of 0.78[95%confidence interval(CI):0.73-0.83].However,a combination of CEA,CA19-9,and CA72-4 showed superior performance,achieving an AUC of 0.87(95%CI:0.83-0.91).Significant correlations were observed between CEA levels and several clinicopatho-logical features,including tumor stage(P<0.001),lymph node involvement(P=0.002),and distant metastasis(P<0.001).Furthermore,in a subgroup analysis of patients diagnosed after July 2022,the integration of fecal occult blood testing with the tumor marker panel(CEA+CA19-9+CA72-4)significantly improved diagnostic accuracy,increasing the AUC to 0.91(95%CI:0.86-0.96).CONCLUSION A multimarker approach combining CEA,CA19-9,and CA72-4 with fecal occult blood testing enhances the preoperative assessment of patients with rectal *** findings suggest potential improvements in risk stratification and management of patients with rect

关键词： Rectal cancer Tumor markers Carcinoembryonic antigen Cancer antigen 19-9 Cancer antigen 72-4 Fecal occult blood test Diagnosis

Mechanism regulation over dual-atom catalyst enables high-performance oxidative alcohol esterification

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Science Bulletin 2025年第1期70卷 78-89页

作者： Ce Liu teng Li Xingchao Dai Jian Zhao Liping Zhang Xinjiang Cui State Key Laboratory of Low Carbon Catalysis and Carbon Dioxide Utilization State Key Laboratory for Oxo Synthesis and Selective OxidationLanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China

The development of heterogeneous catalysts with well-defined uniform isolated or multiple active sites is of great importance for understanding catalytic performances and studying reaction ***,we present a CoCu dual-atom catalyst(CoCu-DAC)where bonded Co-Cu dual-atom sites are embedded in N-doped carbon matrix with a well-defined Co(OH)CuN_(6)*** CoCu-DAC exhibits higher catalytic activity and selectivity than the Co single-atom catalyst(Co-SAC)and Cu single-atom catalyst(CuSAC)counterparts in the catalytic oxidative esterification of alcohols and a variety of methyl and alkyl esters have been successfully *** studies reveal that the activation energy(29.7 kJ mol^(-1))over CoCu-DAC is much lower than that over Co-SAC(38.4 kJ mol^(-1))and density functional theory(DFT)studies disclose that two different mechanisms are regulated over CoCu-DAC and Co-SAC/Cu-SAC in three-step esterification of *** bonded Co-Cu and adjacent N species efficiently catalyze the elementary reactions of alcohol dehydrogenation,O2activation and ester formation,*** stepwise alkoxy pathway(O-H and C-H scissions)is preferred for both alcohol dehydrogenation and ester formation over CoCu-DAC,while the progressive hydroxylalkyl pathway(C-H and O-H scissions)for alcohol dehydrogenation and simultaneous hemiacetal dehydrogenation are favored over Co-SAC and *** peaks in the Fourier transform infrared spectroscopy analysis may confirm the formation of the metal-C intermediate and the hydroxylalkyl pathway over Co-SAC.

关键词： Dual-atom catalysts Oxidative esterification Mechanism regulation Alcohol

基于虚拟同步机的新能源制氢系统协调控制策略

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中国电机工程学报 2025年第1期45卷 163-174,I0013页

作者：袁铁江张江飞滕越大连理工大学电气工程学院辽宁省大连市116024 国网安徽省电力有限公司电力科学研究院安徽省合肥市230601

针对传统控制策略下新能源制氢系统缺乏惯量响应特性,难以主动参与电网调节、系统频率稳定性差等问题,提出基于虚拟同步机(virtual synchronous generator,VSG)的新能源制氢系统协调控制策略。首先,在建立新能源制氢系统模型的基础上,... 详细信息

针对传统控制策略下新能源制氢系统缺乏惯量响应特性,难以主动参与电网调节、系统频率稳定性差等问题,提出基于虚拟同步机(virtual synchronous generator,VSG)的新能源制氢系统协调控制策略。首先,在建立新能源制氢系统模型的基础上,考虑到通过变流器并网的制氢系统惯量缺失和电解槽低功率运行的安全约束,提出基于电解槽与蓄电池的VSG控制方案,建立系统网侧VSG控制模型;其次,为防止VSG过度响应导致系统平抑新能源波动能力下降,提出考虑系统状态的VSG自适应方法;然后,针对系统功率波动影响直流母线电压稳定的问题,设计各单元控制策略,并在电解槽单元加入附加响应控制环节以缓解直流母线电压波动;最后,为实现能量合理分配,针对系统不同运行模式,提出考虑各单元运行状态的能量管理策略。仿真结果表明:所提策略充分发挥了电解槽调节能力,系统具备惯量与一次调频响应特性,频率稳定性增强等。

关键词：新能源制氢虚拟同步机协调控制惯量响应频率调节

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多策略融合的改进黑猩猩优化算法

北京航空航天大学学报 2025年第1期51卷 235-247页

作者：张福兴高腾吴泓达大连工业大学机械工程与自动化学院大连116034

针对黑猩猩优化算法存在迭代速度慢、精度不高及初始化分布不均匀等问题,提出一种融合多策略的改进黑猩猩优化算法。采用改进的Sine混沌映射初始化种群,解决种群边界聚集分布问题,引入考虑线性权重系数、自适应加速因子的粒子群思想,配... 详细信息

针对黑猩猩优化算法存在迭代速度慢、精度不高及初始化分布不均匀等问题,提出一种融合多策略的改进黑猩猩优化算法。采用改进的Sine混沌映射初始化种群,解决种群边界聚集分布问题,引入考虑线性权重系数、自适应加速因子的粒子群思想,配合改进的非线性收敛因子平衡算法的全局搜索能力,加快算法收敛,提高收敛精度。引入自适应水波因子改进麻雀精英突变和Bernoulli混沌映射策略,提高个体跳出局部最优的能力。利用22个基准测试函数进行迭代分析求解和Wilcoxon秩和统计检验,得出所提算法迭代速度更快、精度更高、跳出局部最优能力更强。将所提算法应用到工程实例中,进一步验证算法处理现实优化问题的优越性。

关键词：改进的Sine混沌映射非线性衰减因子麻雀精英突变 Bernoulli混沌映射 Wilcoxon秩和检验

Sentinel-1卫星InSAR干涉图大气校正方法对比——以西藏中部地区为例

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北京大学学报(自然科学版) 2025年第1期61卷 111-120页

作者：樊文智王腾北京大学地球与空间科学学院北京100871

为了评估不同大气校正方法在合成孔径雷达干涉测量技术(InSAR)的形变速率,尤其是时序形变解算中的适用性,介绍两种典型的InSAR大气校正方法——InSAR通用大气校正在线服务(GACOS)和公共影像堆叠法(common-scene-stacking)的计算原理。... 详细信息

为了评估不同大气校正方法在合成孔径雷达干涉测量技术(InSAR)的形变速率,尤其是时序形变解算中的适用性,介绍两种典型的InSAR大气校正方法——InSAR通用大气校正在线服务(GACOS)和公共影像堆叠法(common-scene-stacking)的计算原理。以西藏中部为研究区域,将两种方法用于InSAR干涉图的大气校正,从时序上评估两者的表现,展示其对超过1年的长时间基线干涉图的大气校正效果,最终得到西藏中部地表变形场。结果显示,对于单个干涉图,公共影像堆叠法的大气校正效果明显优于结果不稳定的GACOS,可以让标准差下降60%以上。在时序上,两种方法提供的大气延迟趋势类似,但具体数值相差很大。GACOS对InSAR时序结果起到改善作用,可以根据实际需要,按照两者的优劣进行取舍或结合。

关键词： InSAR 大气校正 GACOS 公共影像堆叠法西藏中部

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具有非凸输入约束的不确定严格反馈系统有限时间自适应跟踪控制

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控制与决策 2025年第02期40卷 608-616页

作者：张腾飞李明星北京航空航天大学自动化科学与电气工程学院

针对一类具有非凸输入约束和外界干扰的不确定多输入多输出严格反馈非线性系统,提出一种有限时间自适应神经网络动态面跟踪控制方案.首先,通过引入非凸约束算子,将所设计反馈控制输入转化为与其同方向具有最大幅值的实际输入向量,进而... 详细信息

针对一类具有非凸输入约束和外界干扰的不确定多输入多输出严格反馈非线性系统,提出一种有限时间自适应神经网络动态面跟踪控制方案.首先,通过引入非凸约束算子,将所设计反馈控制输入转化为与其同方向具有最大幅值的实际输入向量,进而保证实际控制输入始终保持在非凸约束集合内;然后,采用径向基神经网络逼近不确定连续函数向量,以解决控制增益矩阵上下界未知情形下的控制问题,并利用不等式放缩处理未知有界干扰;接着,利用反步法设计有限时间自适应动态面跟踪控制器,保证闭环系统所有信号均为一致最终有界的,实现期望轨迹的有限时间跟踪控制;最后,给出数值仿真算例以表明所提出控制方案的有效性.

关键词：非凸输入约束有限时间稳定动态面控制自适应神经网络反步设计不确定严格反馈系统

Can patients with mild non-neoplastic lesions diagnosed at baseline screening be safely exempt from surveillance: evidence from multicenter community-based cohorts

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Science China(Life Sciences) 2025年第1期68卷 263-271页

作者： Siyi He Zhiyi Zhang Guohui Song Zhenhai Wang Chunyun Dai Shipeng Yan Kun Jiang Bingbing Song He Li Maomao Cao Dianqin Sun Fan Yang Xinxin Yan Shaoli Zhang Yi teng Qianru Li Changfa Xia Wanqing Chen Office of Cancer Screening National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100021China Department of Gastroenterology Gansu Wuwei Tumor HospitalWuwei 730000China Cixian Cancer Institute Handan 056500China Linzhou Cancer Hospital Linzhou 456550China Center for Disease Control and Prevention of Sheyang County Yancheng 224499China Department of Cancer Prevention and Control Hunan Cancer Hospital and The Affiliated Cancer Hospital of Xiangya School of MedicineCentral South UniversityChangsha 410029China Luoshan Center for Disease Control and Prevention Xinyang 464299China Office for Cancer Control and Research Affiliated Cancer Hospital of Harbin Medical UniversityHarbin 150081China

Surveillance recommendations for gastric cancer(GC)in current guidelines focused on advanced precancerous lesions and were based on precise diagnosis of severity/extent of baseline *** aimed to develop a less endoscopy-related equipment-dependent risk-stratification tool,and assessed whether mild-precursor-lesion patients can be safely exempt from *** the multicenter communitybased cohort,75,051 participants receiving baseline endoscopy were enrolled during 2015–2017 and followed-up until *** incidence rates(CIRs)of GC for precancerous-conditions were calculated by Kaplan-Meier method and compared by Log-rank *** Cox regression models were used to detect potential factors for progression towards GC.A risk score was calculated as counts of selected *** independent cohort,including 26,586 participants was used for external *** a median follow-up of 6.25 years,CIRs of GC were 0.302%,0.436%,and 4.756%for normal group,non-neoplastic(atrophic gastritis/intestinal metaplasia)and neoplastic lesions(low-grade/high-grade dysplasia),respectively(Ptrend<0.001).Four predictors,including male,≥60 years,smoking,and limited vegetable consumption,were selected for ***-risk patients(≥3 risk factors)with non-neoplastic lesions showed higher GC risks(adjusted HR=7.73,95%CI:4.29–13.92),and their four-year CIR reached the one-year CIR of neoplastic *** categorizing non-neoplastic lesions by histological grade,both patients with moderate-to-severe lesions(aHR=3.07,95%CI:1.67–5.64)and high-risk patients with mild lesions(aHR=7.29,95%CI:3.58–14.86)showed higher *** trends were observed in validation ***-risk mild-precursor-lesion patients should receive surveillance within 3–5 years after baseline *** study provides evidence on supplementing current guideline recommendations.

关键词： stomach neoplasms precancerous conditions cancer screening cumulative incidence risk stratification

基于模糊集的无线通信网络码间干扰时序抑制算法

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现代电子技术 2025年第3期48卷 13-18页

作者：滕雨彤中国空空导弹研究院河南洛阳417009

受到码间干扰影响,无线通信网络的通信传输过程不够稳定且存在一定风险,而信道状态的不确定性和时变性,增加了干扰抑制的实时性,由此,提出基于模糊集的无线通信网络码间干扰时序抑制算法。建立无线通信网络通信信道模型并展开信道多径... 详细信息

受到码间干扰影响,无线通信网络的通信传输过程不够稳定且存在一定风险,而信道状态的不确定性和时变性,增加了干扰抑制的实时性,由此,提出基于模糊集的无线通信网络码间干扰时序抑制算法。建立无线通信网络通信信道模型并展开信道多径特性测量,以分析无线通信网络中信道的行为特性;基于该特性,采用基于贝叶斯滤波的信道估计方法实时跟踪并准确估计信道状态,为码间干扰抑制提供基础;将估计结果作为输入,选用基于模糊神经网络的盲均衡算法,通过模糊集理论和盲均衡器实现码间干扰时序抑制,增强无线通信网络性能。实验结果表明,所提方法可以有效降低码间干扰的影响,为无线通信网络的稳定传输提供有力的保障。

关键词：信道模型多径特性测量贝叶斯滤波信道估计模糊神经网络盲均衡器模糊集码间干扰抑制

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基于频域分析的热系统高效动态模拟算法

工程热物理学报 2025年第1期46卷 217-225页

作者：李航滕润航赵甜陈群清华大学工程力学系热科学与动力工程教育部重点实验室北京100084 北方工业大学储能科学与工程学院北京100144

换热器的高效、准确动态模拟是热系统性能动态分析的关键,然而基于时、空离散的有限差分/体积法难以兼顾模拟计算的精度与速度,不利于热系统的动态性能分析。本文提出一种频域热系统动态模拟高效算法,通过傅里叶变换导出系统内换热器的... 详细信息

换热器的高效、准确动态模拟是热系统性能动态分析的关键,然而基于时、空离散的有限差分/体积法难以兼顾模拟计算的精度与速度,不利于热系统的动态性能分析。本文提出一种频域热系统动态模拟高效算法,通过傅里叶变换导出系统内换热器的频域控制方程,并将其分解为初始-扰动部分,分别解析和数值求解,叠加得到系统的动态响应。相比于有限差分法,本文所提出算法在保证精度(偏差<0.3 K)的同时可缩短计算时间约一个量级。

关键词：换热器频域分析动态模拟求解算法傅里叶变换