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Concise synthesis of valuable chiral N-Boc-β-benzyl-β-amino acid via construction of chiral N-Boc-3-benzyl-5-oxoisoxazolidine through cross-metathesis/conjugate addition/oxidation

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Chinese Chemical Letters 2017年第2期28卷 471-475页

作者： hong-tao Jiang Hao-Ling gao Cheng-Sheng Ge College of Chemical Engineering Zhejiang University of Technology College of Chemistry and Materials Engineering Quzhou University

Valuable chiral N-Boc-β-benzyl-β-amino acid was concisely synthesized via construction of chiral NBoc-3-benzyl-5-oxoisoxazolidine through cross-metathesis/conjugate addition/*** of the starting materials for the synthesis of chiral N-Boc-β-benzyl-β-amino acid are cheap,and two-step short procedure make it easy for the rapid construction of various chiral β-arylmethyl-β-amino acids and important drugs,such as sitagliptin phosphate.

关键词： Synthetic methods Conjugate addition Organocatalysis Asymmetric catalysis Enantioselective

Cross-subcarrier precoder design for massive MIMO-OFDM downlink with symplectic optimization

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Science China(Information Sciences) 2025年

作者： Yu-Xuan ZHANG An-An LU Xiang-Gen XIA Xi-Qi gao National Mobile Communications Research Laboratory Southeast University Purple Mountain Laboratories Department of Electrical and Computer Engineering University of Delaware

We propose a cross-subcarrier precoder design(CSPD) for massive multiple-input multiple-output(MIMO) orthogonal frequency division multiplexing(OFDM) downlink. This work aims to significantly improve the channel estimation and signal detection performance by enhancing the smoothness of the frequency domain effective channel. This is accomplished by designing a few vectors known as the transform domain precoding vectors(TDPVs), which are then transformed into the frequency domain to generate the precoders for a set of subcarriers. To combat the effect of channel aging, the TDPVs are optimized under imperfect channel state information(CSI). The optimal precoder structure is derived by maximizing an upper bound of the ergodic weighted sum-rate(WSR) and utilizing the a posteriori beam-based statistical channel model(BSCM). To avoid the large-dimensional matrix inversion, we propose an algorithm with symplectic optimization. Simulation results indicate that the proposed cross-subcarrier precoder design significantly outperforms conventional methods.

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Smoothing methods based on coordinate transformation in a linear space and application in airfoil aerodynamic design optimization

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Science China(Technological Sciences) 2015年第2期58卷 297-306页

作者： WANG Chao gao Zheng hong HUANG Jiang tao ZHAO Ke LI Jing National Key Laboratory of Aerodynamic Design and Research Northwestern Polytechnical University China Aerodynamics Research & Development Center

In detailed aerodynamic design optimization,a large number of design variables in geometry parameterization are required to provide sufficient flexibility and obtain the potential optimum ***,with the increasing number of design variables,it becomes difficult to maintain the smoothness on the surface which consequently makes the optimization process progressively *** this paper,smoothing methods based on B-spline functions are studied to improve the smoothness and design *** wavelet smoothing method and the least square smoothing method are developed through coordinate transformation in a linear space constructed by B-spline basis *** these two methods,smoothing is achieved by a mapping from the linear space to itself such that the design space remains unchanged.A design example is presented where aerodynamic optimization of a supercritical airfoil is conducted with smoothing methods included in the optimization *** results from the design example confirm that these two smoothing methods can greatly improve quality and efficiency compared with the existing conventional non-smoothing method.

关键词： smoothness linear space B-spline functions coordinate transformation wavelet least square aerodynamicoptimization

Efficient photocatalytic H2 evolution over tubular mesoporous carbon nitride with N-vacancy by microwave-assisted synthesis

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Science China Chemistry 2025年

作者： Yuanlong Pan Qiang Zhang Guangzheng Huang Yannan Luo honglin gao School of Materials and Energy National Center for International Research on Photoelectric and Energy MaterialsYunnan University

Modifying the microstructure of photocatalysts while simultaneously introducing vacancies has shown significant potential in enhancing their performance for hydrogen production. Herein, a novel tubular mesoporous carbon nitride（TMCN） with nitrogen vacancies was fabricated using a microwave-assisted synthesis strategy, employing melamine-cyanuric acid supramolecular（MC-S） as the precursor. The optimized TMCN exhibited an outstanding H2production rate, approximately 29 times higher than that of pristine g-C3N4. The N-vacancies serve as sites for reactant adsorption and activation, leading to enhanced delocalization of HOMO-LUMO. Furthermore, the porous structures of TMCN facilitate the reactant diffusion, while its tubular architectures promote the oriented transfer of charge carriers. Crucially, the markedly improved photocatalytic performance of TMCN can be predominantly attributed to the synergistic effects arising from its superior structure and N-vacancy defects. This work opens new possibilities for the simultaneous formation of surface defect states as photocatalytic reaction sites and distinctive structures conducive to charge carrier transport.

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Sr-Nd isotopic characteristics and their significance in provenance tracing of detrital sediment in major rivers and marginal seas of eastern China

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Science China Earth Sciences 2025年

作者： Xiaobao gao Chao LI Zhifei DUAN Yulong GUO Shouye YANG State Key Laboratory of Marine Geology Tongji University

Sr-Nd isotopes are widely utilized as reliable tracers in sediment provenance *** this study,we compiled 304Sr and 335 Nd isotope data of fine-grained surface sediments collected from major rivers in eastern China,including the Huanghe River,Changjiang River,southeastern coastal rivers,and rivers in Taiwan Island,as well as from marginal seas （Yellow Sea and East China Sea） and the Okinawa *** comprehensive dataset allowed us to examine the spatial distribution patterns of these isotopes and their implications for provenance *** variations of εNd values in the sediments in Changjiang and Huanghe Basins primarily reflect the diversity of sediment sources,whereas the87Sr/86Sr ratios are influenced by both grain size and source ***,the reduction in87Sr/86Sr ratios observed in the middle and lower Changjiang River is attributed to the inputs of sources characterized by distinct87Sr/86Sr signatures beyond mere grain size *** the southeastern coastal and Taiwan rivers,sediments in the tidal reaches of the Jiao River exhibit hybrid characteristics,a mix of Changjiang-derived sediment and those originating from local ***,the Min River and Jiulong River sediments predominantly reflect local sources,with minimal influence from the Changjiang *** significant isotopic variation of Sr-Nd isotopic characteristics observed between riverine sediments on the eastern and western sides of Taiwan Island underscores the diverse provenance heterogeneity of source rocks in the *** the marginal seas,our data indicates that the surface sediments in the central mud area of the South Yellow Sea and the southern Yellow Sea are predominantly sourced from the Changjiang River catchment,potentially augmented by inputs from Korean *** inner shelf sediments of the East China Sea are primarily influenced by Changjiang River inputs,whereas rivers in eastern Taiwan Island contribute to the sediments on the middle and

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Preparation and study of novel mid-to-low-temperature phase-change molten salts

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Science China Technological Sciences 2025年

作者： Chenxing REN Yifan WANG Xin HE Chenghang ZHENG Xiang gao State Key Laboratory of Clean Energy Utilization Zhejiang University Institute of Carbon Neutrality Zhejiang University Baima Lake Laboratory Zhejiang University

Molten salts is a promising medium for heat storage and heat transfer due to their advantages of low cost, low steam pressure, high energy storage density and wide temperature range. In this paper, a new phase change mixture of molten salts with KNO3, NaNO3, ZnCl2, NaF, Na2CO3, NaCl, and MgO as materials has been prepared through a plenty of experiments. The experimental results show that the melting point of some molten salts can be reduced to 202.9°C, and the decomposition temperature can reach 701.3°C. In addition, its thermophysical properties, including specific heat, viscosity and thermal stability, were measured and analyzed. The average specific heat of some molten salts is as high as 2.53 J/（g K）, and the average thermal conductivity is as high as 0.77 W/（m K）. In the 4-day short-term thermal stability test, the fluctuation of each parameter is minimal, and the overall thermal physical property is relatively stable. Compared with the traditional phase change molten salt, the new hybrid molten salt has a significantly lower melting point, a further improvement in the decomposition temperature, specific heat and other comprehensive thermophysical properties, and a better overall economy, which has important application value in heat transfer and energy storage.

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血尿酸水平对急性冠脉综合征的预测价值

心血管康复医学杂志 2003年第1期12卷 15-17页

作者：李洪涛黄高宗吴宗贵第二军医大学长征医院心内科上海市200003

目的:探讨血尿酸水平对急性冠脉综合征(ACS)的预测意义。方法:收集49例稳定性心绞痛(SAP),50例不稳定性心绞痛(UAP)及52例急性心肌梗死(AMI)病人的空腹血标本,测定尿酸(UA)、甘油三酯(TG)、总胆固醇(TC)、低密度总胆固醇(LDL-C)、空腹血... 详细信息

目的:探讨血尿酸水平对急性冠脉综合征(ACS)的预测意义。方法:收集49例稳定性心绞痛(SAP),50例不稳定性心绞痛(UAP)及52例急性心肌梗死(AMI)病人的空腹血标本,测定尿酸(UA)、甘油三酯(TG)、总胆固醇(TC)、低密度总胆固醇(LDL-C)、空腹血糖(FBG)、肌酐(Cr)的含量,并进行对照比较。结果:3组间TG、TC、LDL-C、FBG及Cr水平无明显差异;UAP组及AMl组的尿酸水平接近,无统计学意义,但明显高于SAP组(P<0.05)。UAP组及AMI组的尿酸异常者比例相似,但也明显高于SA组(P<0.05)。结论:高尿酸血症是CHD的独立危险因子,能促进并预示ACS的发生。

关键词：急性冠脉综合征尿酸预测因素冠心病

Small extracellular vesicles derived from human induced pluripotent stem cell-differentiated neural progenitor cells mitigate retinal ganglion cell degeneration in a mouse model of optic nerve injury

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Neural Regeneration Research 2025年第2期20卷 587-597页

作者： Tong Li Hui-Min Xing Hai-Dong Qian Qiao gao Sheng-Lan Xu Hua Ma Zai-Long Chi State Key Laboratory of Ophthalmology Optometry and Visual ScienceEye HospitalWenzhou Medical UniversityWenzhouZhejiang ProvinceChina National Clinical Research Center for Ocular Diseases Eye HospitalWenzhou Medical UniversityWenzhouZhejiang ProvinceChina

Several studies have found that transplantation of neural progenitor cells(NPCs)promotes the survival of injured ***,a poor integration rate and high risk of tumorigenicity after cell transplantation limits their clinical *** extracellular vesicles(sEVs)contain bioactive molecules for neuronal protection and *** studies have shown that stem/progenitor cell-derived sEVs can promote neuronal survival and recovery of neurological function in neurodegenerative eye diseases and other eye *** this study,we intravitreally transplanted sEVs derived from human induced pluripotent stem cells(hiPSCs)and hiPSCs-differentiated NPCs(hiPSC-NPC)in a mouse model of optic nerve *** results show that these intravitreally injected sEVs were ingested by retinal cells,especially those localized in the ganglion cell *** with hiPSC-NPC-derived sEVs mitigated optic nerve crush-induced retinal ganglion cell degeneration,and regulated the retinal microenvironment by inhibiting excessive activation of *** analysis further revealed that hiPSC-NPC derived sEVs transported neuroprotective and anti-inflammatory miRNA cargos to target cells,which had protective effects on RGCs after optic nerve *** findings suggest that sEVs derived from hiPSC-NPC are a promising cell-free therapeutic strategy for optic neuropathy.

关键词： exosome miRNA neural progenitor cell neurodegeneration neuroinflammation neuroprotection optic nerve crush optic neuropathy retinal ganglion cell small extracellular vesicles

Comparative proteomic analysis of plasma exosomes reveals the functional contribution of N-acetyl-alpha-glucosaminidase to Parkinson’s disease

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Neural Regeneration Research 2025年第10期20卷 2998-3012页

作者： Yuan Zhao Yidan Zhang Xin Liu Jian Zhang Ya gao Shuyue Li Cui Chang Xiang Liu Guofeng Yang Department of Geriatrics Second Hospital of Hebei Medical UniversityShijiazhuangHebei ProvinceChina Department of Neurosurgery The Second Hospital of Hebei Medical UniversityShijiazhuangHebei ProvinceChina

Parkinson’s disease is the second most common progressive neurodegenerative disorder,and few reliable biomarkers are available to track disease *** proteins,DNA,mRNA,and lipids carried by exosomes reflect intracellular changes,and thus can serve as biomarkers for a variety of *** this study,we investigated alterations in the protein content of plasma exosomes derived from patients with Parkinson’s disease and the potential therapeutic roles of these proteins in Parkinson’s *** a tandem mass tag-based quantitative proteomics approach,we characterized the proteomes of plasma exosomes derived from individual patients,identified exosomal protein signatures specific to patients with Parkinson’s disease,and identified N-acetyl-alpha-glucosaminidase as a differentially expressed protein.N-acetyl-alpha-glucosaminidase expression levels in exosomes from the plasma of patients and healthy controls were validated by enzyme-linked immunosorbent assay and western *** results demonstrated that the exosomal N-acetyl-alpha-glucosaminidase concentration was not only lower in Parkinson’s disease,but also decreased with increasing Hoehn-Yahr stage,suggesting that N-acetyl-alpha-glucosaminidase could be used to rapidly evaluate Parkinson’s disease ***,western blot and immunohistochemistry analysis showed that N-acetyl-alpha-glucosaminidase levels were markedly reduced both in cells treated with 1-methyl-4-phenylpyridinium and cells overexpressingα-synuclein compared with control ***,N-acetyl-alpha-glucosaminidase overexpression significantly increased cell viability and inhibitedα-synuclein expression in 1-methyl-4-phenylpyridinium-treated *** together,our findings demonstrate for the first time that exosomal N-acetyl-alpha-glucosaminidase may serve as a biomarker for Parkinson’s disease diagnosis,and that N-acetyl-alpha-glucosaminidase may reduceα-synuclein expression and 1-methyl-4-phenylpyridinium-induced n

关键词： biomarker diagnosis exosomes N-acetyl-alpha-glucosaminidase Parkinson’s disease proteomic α-synuclein