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Chemical Synthesis of a Key Precursor Relevant to the Tetrasaccharide Repeating Unit from Treponema medium ATCC 700293

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Chinese Journal of Chemistry 2024年第14期42卷 1615-1622页

作者： Wenbin Sun Guangzong Tian Meiru Ding Chunjun Qin xiaopeng Zou Jing Hu Jian Yin Key Laboratory of Carbohydrate Chemistry and Biotechnology Ministry of EducationSchool of Biotechnology&School of Life Sciences and Health EngineeringJiangnan UniversityLihu Avenue 1800WuxiJiangsu214122 China Wuxi School of Medicine Jiangnan UniversityLihu Avenue 1800WuxiJiangsu214122 China

Treponema is a Gram-negative anaerobic bacterium,among which the pathogenic Treponema can cause various diseases,such as venereal syphilis(Treponema pallidum),yaws(Treponema carateum),and oral diseases(Treponema denticola and Treponema medium).Although different from conventional lipopolysaccharides,the extracellular glycoconjugate of Treponema may still be a potential antigen and provide a candidate for vaccine ***,we completed the first chemical synthesis of Treponema medium ATCC 700293 tetrasaccharide precursor containing L-ornithine(L-Orn)and D-aspartic acid(D-Asp)*** efficiency of non-reducing end disaccharide formation has been improved by optimizing the assembly of the protecting groups in the donors and ***[3+1]glycosylation strategy attempted to reduce the length of the acceptor to increase the nucleophilicity of the hydroxyl group,thereby improving the efficiency of synthesizing the target *** L-Orn derivative was introduced at the final stage due to its influence on the glycosylation stereospecificity and ***,the successful introduction of two amino acid derivatives and the synthesis of a tetrasaccharide precursor with complex functional-group modifications have provided valuable insights for synthesizing other complex bacterial glycans.

关键词： Glycosylation Total synthesis Treponema medium ATCC 700293 Tetrasaccharide precursor Protecting group Oligosaccharides Regioselectivity Neighboring-group effects

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卫星接收机非线性故障建模与仿真

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信号处理 2022年第4期38卷 739-746页

作者：周晓鹏吴迪胡涛郑州大学中原网络安全研究院河南郑州450001 战略支援部队信息工程大学数据与目标工程学院河南郑州450001

非线性效应导致接收机设备故障以及性能降级一直是卫星通信系统面临的重要挑战。针对这一问题,本文提出了一种基于行为模型的接收机非线性故障分析方法。首先推导分析滤波器内反射干扰在幅频响应上的表现形式,以此构建滤波器故障描述模... 详细信息

非线性效应导致接收机设备故障以及性能降级一直是卫星通信系统面临的重要挑战。针对这一问题,本文提出了一种基于行为模型的接收机非线性故障分析方法。首先推导分析滤波器内反射干扰在幅频响应上的表现形式,以此构建滤波器故障描述模型。其次利用幅相转换关系对Saleh模型系数进行修正,建立表征放大器在过饱和点下不同程度的非线性故障模型。然后针对相位噪声相关性对振荡器频率稳定性的影响,利用一阶自回归模型表征在不同相关性相位噪声下,振荡器内存在的非线性故障。最后将滤波器、功率放大器和振荡器的故障模型级联,建立接收机射频前端整体的非线性故障模型,并通过星座图、功率谱以及电路仿真三方面对模型进行仿真分析和验证。实验结果表明,本文建立的故障行为模型能有效表征接收机射频前端存在的非线性故障。

关键词：卫星接收机非线性故障行为级建模放大器幅相失真振荡器相位噪声

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Parallel Physics-Informed Neural Networks Method with Regularization Strategies for the Forward-Inverse Problems of the Variable Coefficient Modified KdV Equation

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Journal of Systems Science & Complexity 2024年第2期37卷 511-544页

作者： zhou Huijuan School of Science Shanghai Maritime UniversityShanghai 201306China

This paper mainly introduces the parallel physics-informed neural networks(PPINNs)method with regularization strategies to solve the data-driven forward-inverse problems of the variable coefficient modified Korteweg-de Vries(VC-MKdV)*** the forward problem of the VC-MKdV equation,the authors use the traditional PINN method to obtain satisfactory data-driven soliton solutions and provide a detailed analysis of the impact of network width and depth on solving accuracy and ***,the author finds that the traditional PINN method outperforms the one with locally adaptive activation functions in solving the data-driven forward problems of the VC-MKdV *** for the data-driven inverse problem of the VC-MKdV equation,the author introduces a parallel neural networks to separately train the solution function and coefficient function,successfully addressing the function discovery problem of the VC-MKdV *** further enhance the network’s generalization ability and noise robustness,the author incorporates two regularization strategies into the *** amount of numerical experimental data in this paper demonstrates that the PPINNs method can effectively address the function discovery problem of the VC-MKdV equation,and the inclusion of appropriate regularization strategies in the PPINNs can improves its performance.

关键词： Data-driven forward-inverse problems parallel physics-informed neural networks regularization strategies variable coefficient modified KdV equation

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基于神经网络的离散元细观参数标定方法研究——以甘肃黑方台黄土滑坡为例

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岩石力学与工程学报 2020年第S01期39卷 2837-2847页

作者：周小棚许强赵宽耀陈婉琳巨袁臻周琪成都理工大学地质灾害防治与地质环境保护国家重点实验室四川成都610059 广西交通科学研究院有限公司广西南宁530007

离散元细观力学参数与宏观力学参数之间存在着很高的非线性特征,目前人工试算的参数标定方法存在着很大的随机性和盲目性,标定过程效率低,标定结果可重复性差。因此为了找到一种新的准确、高效的参数标定方法,以黑方台2015~2017年发生的... 详细信息

离散元细观力学参数与宏观力学参数之间存在着很高的非线性特征,目前人工试算的参数标定方法存在着很大的随机性和盲目性,标定过程效率低,标定结果可重复性差。因此为了找到一种新的准确、高效的参数标定方法,以黑方台2015~2017年发生的7起典型黄土滑坡为研究对象,采用离散元数值试验及神经网络等方法,首先根据前人力学试验及相关研究确定出6个本征参数的取值,利用室内休止角试验以及GEMM材料数据库,确定出剩余的6个待标定参数的取值范围;然后通过对剩余6个待标定参数的敏感性进行分析,确定出JKR模型能量密度的取值为100J/m^2,并设计出其中6起滑坡以剩余5个待标定参数为变量的系列数值模拟试验,得到各组参数及其对应的模拟形态(滑源区横向宽、滑源区纵向宽、滑坡的壁高、滑坡整体落差、滑距、堆积区横向宽);然后以此作为样本进行神经网络训练,确定出模拟形态与参数之间的映射关系;进而利用此映射关系反演标定出这6起滑坡的最优模拟参数,并以这6组最优模拟参数作为该地区黄土滑坡数值模拟参数的取值范围;最后通过对第7个滑坡的正演结果,验证了该参数取值范围的可靠性和准确性,避免相同地质条件下人工标定参数所带来的复杂性和随机性。

关键词：边坡工程离散元细观参神经网络参数反演

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Influence of stearic acid surface modification on flowability and agglomeration of battery grade Li_(2)CO_(3)powder

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Particuology 2024年第9期92卷 263-277页

作者： Ming zhou Lithium Industry Center Zhejiang New Era Zhongneng Technology Co.Ltd.Shaoxing312000China

This work investigates the flow and agglomeration behaviors of battery grade Li_(2)CO_(3)powder and the influence of stearic acid surface *** degree of agglomeration is directly related to the uniformity of Li_(2)CO_(3)and its powder *** to the Chinese National Nonferrous Metal Industry Standard,battery grade Li_(2)CO_(3)powder has D50 equal to 3–8μm which belongs to a micron-sized superfine ***,with the extension of storage time,the serious agglomeration phenomenon occurs due to the large specific surface area and rough and irregular powder *** Hausner ratio(HR)of the unmodified sample increases from 1.14 to 1.41,and the corresponding flowability is classified as good to ***,among samples with doping stearic acid,the optimum amount of it is 0.10 wt%which exhibits an extremely stable HR value from 1.14 to ***,after 156 days,the repose angle(AR)obtained for samples without surface modification and using 0.10 wt%stearic acid are calculated to be 49°and 28°,*** on the values of HR and AR,the flowability of the unmodified sample is poor while the sample modified with 0.10 wt%of stearic acid still maintain excellent powder flow ***,The LiMn_(2)O_(4)cathode material synthesized from modified Li_(2)CO_(3)powder with a stearic acid content of 0.10 wt%exhibits good crystallinity and comparable electrochemical performance to that prepared by commercial Li_(2)CO_(3).These results indicate that stearic acid has the potential to be an ideal modifier for battery grade Li_(2)CO_(3)powder that needs to be kept for a long time.

关键词： Battery grade Li_(2)CO_(3)powder Flowability Surface modification Stearic acid

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Human radiological safety assessment for petawatt laser-driven ion acceleration experiments in CLAPA-T

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Matter and Radiation at Extremes 2024年第4期9卷 8-15页

作者： xiaopeng Zhang Jiarui Zhao Shengxuan Xu Xun Chen Ying Gao Shiyou Chen Kun Zhu Xueqing Yan Wenjun Ma State Key Laboratory of Nuclear Physics and Technology and Key Laboratory of HEDP of the Ministry of EducationCAPTPeking UniversityBeijing 100871China Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsCASBeijing 100049China Beijing Laser Acceleration Innovation Center HuairouBeijing 101400China Institute of Guangdong Laser Plasma Technology BaiyunGuangzhou 510540China

The newly built Compact Laser Plasma Accelerator-Therapy facility at Peking University will deliver 60 J/1 Hz laser pulses with 30 fs *** by this petawatt laser facility,proton beams with energy up to 200 MeV are expected to be generated for tumor *** high-repetition operation,both prompt radiation and residual radiation may cause safety ***,human radiological safety assessment before commissioning is *** this paper,we simulate both prompt and residual radiation using the Geant4 and FLUKA Monte Carlo codes with reasonable proton and as-produced electron beam *** find that the prompt radiation can be shielded well by the concrete wall of the experimental hall,but the risk from residual radiation is nonnegligible and necessitates adequate radiation *** the basis of the simulation results,we discuss the constraints imposed by radiation safety considerations on the annual working time,and we propose radiation cooling strategies for different shooting modes.

关键词： laser prompt acceleration

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Extraction and bioactivities of the chemical composition from Pleurotus ostreatus:a review

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Journal of Future Foods 2024年第2期4卷 111-118页

作者： Qingchun Zhao xiaopeng Liu Lili Cui Changyang Ma National R&D Center for Edible Fungus Processing Technology Henan UniversityKaifeng 475004China Functional Food Engineering Technology Research Center Kaifeng 475004China Joint International Research Laboratory of Food&Medicine Resource Function Kaifeng 475004China

Pleurotus ostreatus as an edible mushroom with pharmacological potential,belonging to class basidiomycetes of kingdom Mycota is known to have immense therapeutic *** contains polysaccharides,proteins,sterols,volatile oils and *** has a variety of biological activities,including anti-oxidant,anti-hyperlipidemic,anti-tumor,immunoregulatory and *** paper summarizes the extraction methods,chemical components and biological activities of ***,and find it is good resources to develop medicine and health food.

关键词： Pleurotus ostreatus Extraction methods Chemical components Biological activities

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A Real-time Lithological Identification Method based on SMOTE-Tomek and ICSA Optimization

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Acta Geologica Sinica(English Edition) 2024年第2期98卷 518-530页

作者： DENG Song PAN Haoyu LI Chaowei YAN xiaopeng WANG Jiangshuai SHI Lin PEI Chunyu CAI Meng College of Petroleum Engineering Changzhou UniversityChangzhouJiangsu 213000China

In petroleum engineering,real-time lithology identification is very important for reservoir evaluation,drilling decisions and petroleum geological exploration.A lithology identification method while drilling based on machine learning and mud logging data is studied in this *** method can effectively utilize downhole parameters collected in real-time during drilling,to identify lithology in real-time and provide a reference for optimization of drilling *** the imbalance of lithology samples,the synthetic minority over-sampling technique(SMOTE)and Tomek link were used to balance the sample number of five ***,this paper introduces Tent map,random opposition-based learning and dynamic perceived probability to the original crow search algorithm(CSA),and establishes an improved crow search algorithm(ICSA).In this paper,ICSA is used to optimize the hyperparameter combination of random forest(RF),extremely random trees(ET),extreme gradient boosting(XGB),and light gradient boosting machine(LGBM)*** addition,this study combines the recognition advantages of the four *** accuracy of lithology identification by the weighted average probability model reaches *** study of this paper realizes high-precision real-time lithology identification method,which can provide lithology reference for the drilling process.

关键词： mud logging data real-time lithological identification improved crow search algorithm petroleum geological exploration SMOTE-Tomek

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对城市道路人非共板横断面的探讨

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上海建设科技 2010年第3期 39-40,45页

作者：周小鹏上海市公安局交通警察总队

城市道路人非共板横断面是指非机动车车道与人行道处于同一平面、中间设置分界线或分隔设施的断面形式。与人非共板断面相对应的，是非机动车与人行道处于不同平面的常规断面，但人行道平面高于非机动车道。在2005—2008年前后，“人非... 详细信息

城市道路人非共板横断面是指非机动车车道与人行道处于同一平面、中间设置分界线或分隔设施的断面形式。与人非共板断面相对应的，是非机动车与人行道处于不同平面的常规断面，但人行道平面高于非机动车道。在2005—2008年前后，“人非共板”断面形式在本市新改建道路中应用较多。之后行业内对这一断面形式的态度逐渐发生转变，由普遍推广到褒贬不一。

关键词：城市道路横断面非机动车道板同一平面断面形式人行道分界线

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Integrative transcriptome analysis identifies MYBL2 as a poor prognosis marker for osteosarcoma and a pan-cancer marker of immune infiltration

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Genes & Diseases 2024年第3期11卷 351-367页

作者： Xinzhu Quiu Hongbo He Hao Zeng xiaopeng Tongg Can Zhang Yupeng Liu Zhan Liao Qing Liu Department of Orthopaedics Xiangya HospitalCentral South UniversityChangshaHunan 410008China National Clinical Research Center for Geriatric Disorders Xiangya HospitalChangshaHunan 410008China Department of Sports Medicine Research Center of Sports MedicineXiangya HospitalCentral South UniversityChangshaHunan 410008China

MYBL2(MYB proto-oncogene like 2)is an emerging prognostic marker for malignant tumors,and its potential role in osteosarcoma and its relationship with immune infiltration in pan-cancer is yet to be *** constructed a transcription factor activity profile of os-teosarcoma using the single-cell regulatory network inference algorithm based on single-cell RNA sequencing data obtained from the Gene Expression ***,we calcu-lated the extent of MYBL2 activation in malignant proliferative *** also explored the association between MYBL2 and chemotherapy resistance in ***,we systematically correlated MYBL2 with immunological signatures in the tumor microenviron-ment in pan-cancer,including immune cell infiltration,immune checkpoints,and tumor immu-notherapy ***,we developed and validated a risk score(MRGS),derived an osteosarcoma risk score nomogram based on MRGS,and tested its ability to predict ***2 and gene enrichment analyses in osteosarcoma and pan-cancer revealed that MYBL2 was positively correlated with cell proliferation and tumor immune ***2 expres-sion positively correlated with SLC19A1 in pan-cancer and osteosarcoma cell ***-cancer immune infiltration analysis revealed that MYBL2 was correlated with myeloid-derived sup-pressor cells,Th2 cell infiltration,CD276,RELT gene expression,and tumor mutation burden.

关键词： Biomarker Immunecheckpoint MYBL2 Osteosarcoma Pan-cancer

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