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Double [5]carbohelicene: facile synthesis, chiroptical properties,isomerization study, and lasing application

Science China Chemistry 2025年第1期68卷 233-240页

作者： Peipei liu yantong Li Meng-Xiang Wu Hao Kang Xiao-Li Zhao lin Xu linlin liu Xiaodong Li Junfeng Fang Zhiwei Fang ya Cheng Hai-Bo yang Huakang Yu Xueliang Shi State Key Laboratory of Petroleum Molecular & Process Engineering Shanghai Key Laboratory of Green Chemistry and Chemical ProcessesSchool of Chemistry and Molecular Engineering East China Normal University School of Physics and Optoelectronics South China University of Technology Institute of Polymer Optoelectronic Materials & Devices State Key Laboratory of Luminescent Materials & Devices South China University of Technology School of Physics and Electronic Science Engineering Research Center of Nanophotonics & Advanced Instrument Ministry of EducationEast China Normal University State Key Laboratory of Precision Spectroscopy School of Physics and Electronic Science East China Normal University

Double carbohelicenes have attracted considerable attention due to their aesthetic structures, distinct π-conjugation extension, inherent chirality, and intriguing optical and electronic properties. Herein, the concise de novo synthesis of a new double[5]carbohelicene 1 together with its chiroptical properties, isomerization process and lasing application is presented. 1 was synthesized by a simple protocol involving the formation of a 6,6′-bipentacene as the key intermediate. It is worth noting that1 existed as two diastereomers 1-PP/MM and 1-PM, which were successfully isolated and unambiguously confirmed by Xray crystallography. The optical resolution of the racemic 1-PP/MM was successfully achieved by chiral-phase highperformance liquid chromatography（HPLC）, and 1-PP and 1-MM were characterized by circular dichroism. Interestingly, it was found that 1-PP/MM could be completely isomerized to 1-PM upon heating, and the detailed thermodynamics and kinetics of the isomerization process were systematically investigated. 1-PM exhibited deep-red luminescence with emission maximum at 723 nm and fluorescence quantum yield as high as 32.95%. Consequently, we can showcase the lasing application of 1-PM by doping with epoxy resin to assemble a bottle microlaser spontaneously, which the lasing wavelength is 796.6 nm at a threshold of 0.8 m J cm-2. We believe that our studies, including the facile synthesis methodology, detailed isomerization studies, and lasing application, will shed some light on the design and synthesis of novel carbohelical systems with more functions.

关键词： double carbohelicene optical resolution organic laser isomerization X-ray diffraction

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Genetic counseling, prenatal screening and diagnosis of Down syndrome in the second trimester in women of advanced maternal age： a prospective study

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Chinese Medical Journal 2013年第11期126卷 2007-2010页

作者： QI Qing-wei JIANG Yu-lin ZHOU Xi-ya liu Jun-tao YIN Jie BIAN Xu-ming Department of Obstetrics and Gynecology Chinese Academy ofMedical Science Peking Union Medical College Peking UnionMedical College Hospital Beijing 100730 China

Background The incidence of autosomal trisomy in livebirths is strongly dependent on maternal age. Special consideration is given to the provision of prenatal screening and cytogenetic testing to women of advanced maternal age （AMA）. The aim of this study was to evaluate the effectiveness of second trimester prenatal screening and amniocentesis for Down syndrome （DS） and compare the trends of choice of screening and amniocentesis among AMA women. Methods A total of 5404 AMA patients with natural singleton pregnancy were recruited for this prospective study from January 2008 to December 2010. The gestational weeks were from 15 weeks to 20~6 weeks. The patients referred were grouped into a screening group （2107 cases） and an amniocentesis group （3297 cases） by their own decision. The prevalence of DS was compared between the two groups by chi-square test. Choice rates for each maternal age with trends were compared by regression analysis. Results There were 18 cases of fetal DS detected in the screening group with a prevalence of 8.54%o （18/2107）. Twenty- five cases of fetal DS were diagnosed in the amniocentesis group with a prevalence of 7,58%0 （25/3297）. No statistical difference was observed in the prevalence of DS between the screening and amniocentesis group （P=0.928）. The invasive testing rate for DS in the amniocentesis group was 5.54 times higher than that of the screening group （1/131.88 vs. 1/23.78）. With the increase of the maternal age, the choice of amniocentesis increased while the choice of the screening showed an opposite trend. The choice of the AMA women between the screening and amniocentesis was significantly age relevant （P=0.012）. Conclusions The second trimester serum screening age alone to screen for DS. We suggest educating screening and amniocentesis options. in combination with maternal age was more effective than maternal the patients by recommending AMA women be informed of both

关键词： genetic counseling advanced maternal age Down syndrome prenatal screening genetic amniocentesis second trimester

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Effects of Diets with Different Corn-to-Soybean Ratios on Performance of Lactational Rex Rabbits

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Animal Husbandry and Feed Science 2010年第1期2卷 24-26,31页

作者： SUN Li-na GU Zi-lin liu ya-juan LI Su-min College of Animal Science & Technology Agricultural University of Hebei Baoding 071001 China

[ Objective] To study the effects of diets with different com-to-soybean ratios on production performance of lactational Rex rabbits and select the best feed formula. [Method] A total of 80 lactational healthy Rex rabbits （similar age, body weight and delivery time） were randomly divided into five groups, 16 in each group. The Rex rabbits in group I were fed with corn-based meal diet, group II with soybean-based meal diet, group III with the developed corn-soybean meal diet, group IV with corn-soybean meal free diet, and group CK with conventional corn-soybean meal diet. During the lactation period, the changes in the lactation performance, growth rate of baby rabbits, weight and feed costs were observed. [ Result] The lactation performance of mother rabbits and the growth rate of baby rabbits in the experimental groups were similar to that in the control group. The weaning survival rate of the group III was the highest, but it was not significantly higher than that of the control group. The weaning survival rate of the other three groups was lower than that of the control group （P〈0.05）. The weight loss of mother rabbits in the group I, II and III was not significantly different from that of the control group, but the weight loss of the group IV was higher than that of the control group （ P 〈 0.01 ）. [ Conclusion] Diets with appropriate corn-to-soybean ratios not only reduce feed costs but also give the best feeding effects.

关键词： Lactational Rex rabbits Lactation performance Growth rate Weight Feed costs

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Clinical features and risk factors of severely and critically ill patients with COVID-19

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World Journal of Clinical Cases 2022年第3期10卷 840-855页

作者： Xin Chu Gui-Fang Zhang Yong-Ke Zheng Yi-Gang Zhong Li Wen Ping Zeng Chun-Yi Fu Xun-Liang Tong Yun-Fei Long Jing Li ya-lin liu Zhi-Gang Chang Huan Xi Department of Surgical Intensive Care Medicine Beijing HospitalNational Center of GerontologyInstitute of Geriatric MedicineChinese Academy of Medical SciencesBeijing 100730China The Key Laboratory of Geriatrics Beijing Institute of GeriatricsInstitute of Geriatric MedicineChinese Academy of Medical SciencesBeijing Hospital/National Center of Gerontology of National Health CommissionBeijing 100730China Department of Intensive Care Unit Affiliated Hangzhou First People's HospitalZhejiang University School of MedicineHangzhou 310006Zhejiang ProvinceChina Department of Cardiology Affiliated Hangzhou First People's HospitalZhejiang University School of MedicineHangzhou 310006Zhejiang ProvinceChina Department of Emergency Beijing HospitalNational Center of GerontologyInstitute of Geriatric MedicineChinese Academy of Medical SciencesBeijing 100730China Department of Respiratory and Critical Care Medicine Beijing HospitalNational Center of GerontologyInstitute of Geriatric MedicineChinese Academy of Medical SciencesBeijing 100730China Department of Neurology Beijing HospitalNational Center of GerontologyInstitute of Geriatric MedicineChinese Academy of Medical SciencesBeijing 100730China Department of Cardiology Beijing HospitalNational Center of GerontologyInstitute of Geriatric MedicineChinese Academy of Medical SciencesBeijing 100730China Department of Geriatrics Beijing HospitalNational Center of GerontologyNational Health CommissionInstitute of Geriatric MedicineChinese Academy of Medical SciencesBeijing 100730China

BACKGROUND As of June 1,2020,over 370000 coronavirus disease 2019(COVID-19)deaths have been reported to the World Health ***,the risk factors for patients with moderate-to-severe or severe-to-critical COVID-19 remain *** To explore the characteristics and predictive markers of severely and critically ill patients with *** A retrospective study was conducted at the B11 Zhongfaxincheng campus and E1-3 Guanggu campus of Tongji Hospital affiliated with Huazhong University of Science and Technology in *** with COVID-19 admitted from 1st February 2020 to 8th March 2020 were enrolled and categorized into 3 groups:The moderate group,severe group and critically ill *** data,demographic data,clinical symptoms and outcomes,complications,laboratory tests and radiographic examinations were collected retrospectively from the hospital information system and then compared between *** A total of 126 patients were *** were 59 in the moderate group,49 in the severe group,and 18 in the critically ill *** logistic regression analysis showed that age[odd ratio(OR)=1.055,95%(confidence interval)CI:1.099-1.104],elevated neutrophil-to-lymphocyte ratios(OR=4.019,95%CI:1.045-15.467)and elevated high-sensitivity cardiac troponin I(OR=10.126,95%CI:1.088-94.247)were high-risk *** The following indicators can help clinicians identify patients with severe COVID-19 at an early stage:age,an elevated neutrophil-to-lymphocyte ratio and high sensitivity cardiac troponin I.

关键词： COVID-19 SARS-CoV-2 Critically ill Risk factors Aspartate transaminase Amino-terminal pro-brain natriuretic peptide Creatinine Calcium

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Unraveling the Stray Current-Induced Interfacial Transition Zone(ITZ)Effect on Sulfate Corrosion in Concrete

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Engineering 2024年第10期41卷 130-152页

作者： Yong-Qing Chen lin-ya liu Da-Wei Huang Qing-Song Feng Ren-Peng Chen Xin Kang School of Transportation Engineering East China Jiaotong UniversityNanchang 330013China College of Civil Engineering Hunan UniversityChangsha 410082China Key Laboratory of Building Safety and Energy Efficiency of Ministry of Education&National Center for International Research Collaboration in Building Safety and Environment Hunan UniversityChangsha 410082China

The rail transit in sulfate-rich areas faces the combined effects of stray current and salt corrosion;however,the sulfate ion transport and concrete degradation mechanisms under such conditions are still *** address this issue,novel sulfate transport and mesoscale splitting tests were designed,with a focus on considering the differences between the interfacial transition zone(ITZ)and cement *** the influence of stray current,the ITZ played a pivotal role in regulating the transport and mechanical failure processes of sulfate attack,while the tortuous and blocking effects of aggregates almost *** phenomenon was termed the“stray current-induced ITZ effect.”The experimental data revealed that the difference in sulfate ion transport attributed to the ITZ ranged from 1.90 to 2.31 times,while the difference in splitting strength ranged from 1.56 to 1.64 *** the real-time synchronization of splitting experiments and microsecond-responsive particle image velocimetry(PIV)technology,the mechanical properties were exposed to the consequences of the stray currentinduced ITZ *** number of splitting cracks in the concrete increased,rather than along the central axis,which was significantly different from the conditions without stray current and the ideal Brazilian disk ***,a sulfate ion mass transfer model that incorporates reactivity and electrodiffusion was meticulously *** embedded finite element calculation exhibited excellent agreement with the experimental results,indicating its reliability and ***,the stress field was determined utilizing analytical methods,and the mechanism underlying crack propagation was successfully *** to the cement matrix,a stray current led to more sulfates,more microstructure degradation,and greater increases in thickness and porosity in the ITZ,which was considered to be the essence of the stray current-induced ITZ effect.

关键词： Interfacial transition zone(ITZ)effect Stray current Sulfate attack Transport mechanism Splitting test Microstructure

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Offload Strategy for Edge Computing in Satellite Networks Based on Software Defined Network

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Computers, Materials & Continua 2025年第1期82卷 863-879页

作者： Zhiguo liu Yuqing Gui lin Wang Yingru Jiang Communication and Network Laboratory Dalian UniversityDalian116622China College of Environment and Chemical Engineering Dalian UniversityDalian116622China

Satellite edge computing has garnered significant attention from researchers;however,processing a large volume of tasks within multi-node satellite networks still poses considerable *** sharp increase in user demand for latency-sensitive tasks has inevitably led to offloading bottlenecks and insufficient computational capacity on individual satellite edge servers,making it necessary to implement effective task offloading scheduling to enhance user *** this paper,we propose a priority-based task scheduling strategy based on a Software-Defined Network(SDN)framework for satellite-terrestrial integrated networks,which clarifies the execution order of tasks based on their ***,we apply a Dueling-Double Deep Q-Network(DDQN)algorithm enhanced with prioritized experience replay to derive a computation offloading strategy,improving the experience replay mechanism within the Dueling-DDQN ***,we utilize the Deep Deterministic Policy Gradient(DDPG)algorithm to determine the optimal resource allocation strategy to reduce the processing latency of *** results demonstrate that the proposed d3-DDPG algorithm outperforms other approaches,effectively reducing task processing latency and thus improving user experience and system efficiency.

关键词： Satellite network edge computing task scheduling computing offloading

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RF Optimizer Model for Predicting Compressive Strength of Recycled Concrete

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 215-223页

作者： liu lin WANG liuyan WANG Hui SUN Huayue School of Civil Engineering and Architecture Shenyang UniversityShenyang 110000China

Traditional machine learning(ML)encounters the challenge of parameter adjustment when predicting the compressive strength of reclaimed *** address this issue,we introduce two optimized hybrid models:the Bayesian optimization model(B-RF)and the optimal model(Stacking model).These models are applied to a data set comprising 438 observations with five input variables,with the aim of predicting the compressive strength of reclaimed ***,we evaluate the performance of the optimized models in comparison to traditional machine learning models,such as support vector regression(SVR),decision tree(DT),and random forest(RF).The results reveal that the Stacking model exhibits superior predictive performance,with evaluation indices including R2=0.825,MAE=2.818 and MSE=14.265,surpassing the traditional ***,we also performed a characteristic importance analysis on the input variables,and we concluded that cement had the greatest influence on the compressive strength of reclaimed concrete,followed by ***,the Stacking model can be recommended as a compressive strength prediction tool to partially replace laboratory compressive strength testing,resulting in time and cost savings.

关键词： machine learning recycled concrete compressive strength

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Recent development in electrode design for wide-temperature supercapacitors

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Science China Chemistry 2025年第1期68卷 96-117页

作者： Jianhong liu Qiang Zhou Yuxiao lin Xinsheng Zhao Guangmin Zhou Xiaoxiao Li School of Physics and Electronic Engineering Jiangsu Normal University Tsinghua-Berkeley Shenzhen Institute & Tsinghua Shenzhen International Graduate School Tsinghua University

An ever-increasing market demand has stimulated the soaring enthusiasm of researchers to develop wide-temperature supercapacitors(SCs). The active electrode is one of the most important parts of SC, which is directly related to the energy density,power transmission and long-term cyclability of the device in the wide-temperature environment. Compared with the SC electrodes aimed for room-temperature application, the SC electrodes for operating at wide-temperature scene often face greater challenges. In this review, the main challenges of SC electrodes under various temperature conditions, including low, high and cross-fade temperatures, are summarized. The relevant performance decay and failure mechanisms of wide-temperature SC electrodes are analyzed. In addition, this review deals with the recent studies and developments in robust wide-temperature SC electrodes with respect to the rational design of electrode structures and the exploitation of advanced active materials. Finally, the future directions for exploring reliable wide-temperature SCs are also proposed.

关键词： supercapacitor wide-temperature electrode design active materials

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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

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Electrocatalytic cleavage of a lignin β-O-4 model compound and coupling with nitrogen-containing aromatics using Prussian blue analogue-derived nickel–cobalt spinel

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Journal of Energy Chemistry 2025年第1期100卷 628-636页

作者： Yi Qi Xueying Chen Bowen liu Xuliang lin Xueqing Qiu yanlin Qin Guangdong Provincial Key Laboratory of Plant Resources Biorefinery School of Chemical Engineering and Light Industry Guangdong University of Technology Guangdong Provincial Laboratory of Chemistry and Fine Chemical Engineering Jieyang Center Guangdong Basic Research Center of Excellence for Ecological Security and Green Development Guangdong University of Technology

Electrochemical conversion of lignin for the production of high-value heterocyclic aromatic compounds has great *** demonstrate the targeted synthesis and cation modulation of NiCo2O4spinel nanoboxes,synthesized via cation exchange and calcination *** catalysts exhibit excellent efficacy in the electrocatalytic conversion of lignin model compounds,specifically 2-phenoxy-1-phenylethanol,into nitrogen-containing aromatics,achieving high conversion rates and *** catalysts were synthesized via a cation exchange and calcination oxidation process,using Prussian blue nanocubes as *** porous architecture and polymetallic composition of the NiCo2O4spinel demonstrated superior performance in electrocatalytic oxidative coupling,achieving a 99.2 wt%conversion rate of the 2-phenoxy-1-phenylethanol with selectivities of 37.5 wt%for quinoline derivatives and 31.5 wt%for *** innovations include the development of a sustainable one-pot synthesis method for quinoline derivatives,the elucidation of a multistage reaction pathway involving CAO bond cleavage,hydroxyaldol condensation,and CAN bond formation,and a deeper mechanistic understanding derived from DFT *** work establishes a new strategy for lignin valorization,offering a sustainable route to produce high-value nitrogen-containing aromatics from renewable biomass under mild conditions,without the need for additional reagents.

关键词： Spinel Biomass valorization Electrocatalysis Lignin oxidation Coupling

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