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Chemical constituents from the aerial parts of Euphorbia sikkimensis and their bioactivities

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Natural Products and Bioprospecting 2013年第3期3卷 112-116页

作者： da-song yang Wei-Bing PENG Zi-Lei LI Xue WANG Jian-Guo WEI Ke-Chun LIU Yong-Ping yang Xiao-Li LI Key Laboratory of Economic Plants and Biotechnology Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China Plant Germplasm and Genomics Center the Germplasm Bank of Wild SpeciesKunming Institute of BotanyChinese Academy of SciencesKunming 650201China Institute of Tibetan Plateau Research at Kunming Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China Biology Institute of Shandong Academy of Sciences Jinan 250014China

Phytochemical investigation of the aerial parts of Euphorbia sikkimensis led to the isolation of one new diterpenoids,named sikkimenoid E(1),together with thirteen other known compounds(2-14).Their structures were established by means of spectroscopic *** 2 was identified to be a trinortriterpenoid,and derived for the first time from a natural *** this paper we reveal for the first time its comprehensive spectral data and NMR spectral *** 4 showed anti-angiogenic activity with an IC_(50) value of 5.66μM in a zebrafish model,and compounds 5 and 6 exhibited cytotoxicity toward A549 cell line with IC_(50) values of 12.12 and 6.45μM,respectively.

关键词： Euphorbia sikkimensis ingenol trinortriterpenoid tocopherol derivatives bioactivities

全国统筹条件下城镇职工养老保险统筹基金的精算评估

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中国地质大学学报（社会科学版） 2018年第3期18卷 133-143页

作者：邓大松杨晶武汉大学社会保障研究中心

利用精算评估模型考察全国统筹背景下2018—2040年城镇职工基础养老金统筹账户收支平衡状况。经过测算:全国统筹条件下,短期内不会出现城镇职工养老保险统筹账户基金"收不抵支"问题。预测期内,中国城镇职工基本养老保险统筹账户基金收... 详细信息

利用精算评估模型考察全国统筹背景下2018—2040年城镇职工基础养老金统筹账户收支平衡状况。经过测算:全国统筹条件下,短期内不会出现城镇职工养老保险统筹账户基金"收不抵支"问题。预测期内,中国城镇职工基本养老保险统筹账户基金收入呈现出了逐年递增的变动趋势,但是基金收入增速总体"趋缓"。基金支出随着时间序列的变化,呈现出明显的"增加—减少—增加"的波动特征。测算的全国统筹条件下城镇职工基本养老保险统筹基金当期结余始终为正值,但2038年后逐年"缩窄",使得未来中长期养老保险基金收支失衡问题进一步恶化。进一步研究发现,全国统筹条件下延迟退休年龄政策的实施确实能够有效缓解城镇职工基础养老金收支失衡问题。与"未延退"相比,基础养老金全国统筹条件下"延退"后的基金支付能力更强。基于此,从开源节流、精算平衡和激励机制设计三个方面,提出全国统筹条件下确保养老保险基金积累持续增长的政策措施。

关键词：全国统筹延迟退休统筹账户收支平衡

Chemical Constituents from Hypericum beanii

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Chinese Herbal Medicines 2015年第4期7卷 375-379页

作者： da-song yang Zi-lei Li Yong-ping yang Xiao-li Li Wei-lie Xiao Key Laboratory of Economic Plants and Biotechnology Germplasm Bank of Wild Species in Southwest China Institute of Tibetan Plateau Research at Kunming Kunming Institute of Botany Chinese Academy of Sciences State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of Botany Chinese Academy of Sciences

Objective To study the chemical constituents from the aerial parts of Hypericum beani/. Methods Various chromatographic techniques were used to separate the constituents and their structures were elucidated on the basis of extensive spectroscopic interpretation. Results Fifteen compounds were isolated from the aerial parts of H. beanii. Their structures were identified as hyperbeanol E （1）, （E）-Iinalool-l-oic acid （2）, （4S,5R）-5-（4＇-methyl-3＇-pentenyl）-4-hydroxy-5-methyl- dihydrofuran-2-one （3）, benzoic acid （4）, 4-（3-O-3＂）-3＂-methylbutenyl-6-phenyl- pyran-2-one （5）, 4-hydroxy-4a,7-dimethoxy-4,4a-dihydrodibenzo-p-dioxJn-2（3H）- one （6）, isoimperatorin （7）, 2,3-dimethoxyxanthone （8）, 3,4-dihydroxy-2- methoxyxanthone （9）, osajaxanthone （10）, nigrolineaxanthone F （1 1）, hypercohone G （12）, betulinic acid （1 3）, oleanolic acid 3.13-caffeate （14）, and isoastilbin （1 5）. Conclusion Compound 1 is a new menthane monoterpene derivative which owns an extra lactone ring. Compounds 2-7 and 10-1 5 are isolated from genus Hypericum Linn. for the first time and the other compounds are first obtained from the plants in H. beanii.

关键词： hyperbeanol E Hypericum Linn. Hypericum beanii menthane monoterpene spirocyclic acylphloroglucinol xanthone

A New Geranylated 2-Arylbenzofuran from Morus alba

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Chinese Herbal Medicines 2015年第2期7卷 191-194页

作者： da-song yang Zi-lei Li Yong-ping yang Wei-lie Xiao Xiao-li Li Key Laboratory of Economic Plants and Biotechnology Germplasm Bank of Wild Species in Southwest ChinaInstitute of Tibetan Plateau Research at Kunming Kunming Institute of Botany Chinese Academy of Sciences State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of Sciences

Objective To study the chemical constituents from the root barks of Morus alba. Methods Various chromatographic techniques were used to separate the constituents and their structures were elucidated on the basis of extensive spectroscopic interpretation. Results Six compounds were isolated from the root barks of M. alba. The structure of new compound, named as albafuran D（1）, was established together with known compounds sanggenon H（2）, kuwanon E（3）, kuwanon U（4）, kuwanon F（5）, and benzokuwanon E（6）. Conclusion Compound 1 is a new geranylated 2-arylbenzofuran.

关键词： albafuran D Morus alba L. prenylated flavonoids 2-arylbenzofuran

Stochastic Augmented-Based Dual-Teaching for Semi-Supervised Medical Image Segmentation

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Computers, Materials & Continua 2025年第1期82卷 543-560页

作者： Hengyang Liu yang Yuan Pengcheng Ren Chengyun song Fen Luo School of Computer Science and Engineering Chongqing University of TechnologyChongqing400054China College of Artificial Intelligence Chongqing Technology and Business UniversityChongqing400067China

Existing semi-supervisedmedical image segmentation algorithms use copy-paste data augmentation to correct the labeled-unlabeled data distribution ***,current copy-paste methods have three limitations:(1)training the model solely with copy-paste mixed pictures from labeled and unlabeled input loses a lot of labeled information;(2)low-quality pseudo-labels can cause confirmation bias in pseudo-supervised learning on unlabeled data;(3)the segmentation performance in low-contrast and local regions is less than *** design a Stochastic Augmentation-Based Dual-Teaching Auxiliary Training Strategy(SADT),which enhances feature diversity and learns high-quality features to overcome these *** be more precise,SADT trains the Student Network by using pseudo-label-based training from Teacher Network 1 and supervised learning with labeled data,which prevents the loss of rare labeled *** introduce a bi-directional copy-pastemask with progressive high-entropy filtering to reduce data distribution disparities and mitigate confirmation bias in *** the mixed images,Deep-Shallow Spatial Contrastive Learning(DSSCL)is proposed in the feature spaces of Teacher Network 2 and the Student Network to improve the segmentation capabilities in low-contrast and local *** this procedure,the features retrieved by the Student Network are subjected to a random feature perturbation *** two openly available datasets,extensive trials show that our proposed SADT performs much better than the state-ofthe-art semi-supervised medical segmentation *** only 10%of the labeled data for training,SADT was able to acquire a Dice score of 90.10%on the ACDC(Automatic Cardiac Diagnosis Challenge)dataset.

关键词： Semi-supervised medical image segmentation contrastive learning stochastic augmented

Study on the hydrogen absorption properties of a YGdTbDyHo rare-earth high-entropy alloy

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 127-135页

作者： Tongyue Li Ziliang Xie Wenjiao Zhou Huan Tong dawen yang Anjia Zhang Yuan Wu Xiping song State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China Whole Win(Beijing)Materials Sci.&Tech.Co. Ltd.Beijing 100083China

This study investigated the microstructure and hydrogen absorption properties of a rare-earth high-entropy alloy(HEA),*** indicated that the YGdTbDyHo alloy had a microstructure of equiaxed grains,with the alloy elements distributed *** hydrogen absorption,the phase structure of the HEA changed from a solid solution with an hexagonal-close-packed(HCP)structure to a high-entropy hydride with an faced-centered-cubic(FCC)structure without any secondary phase *** alloy demonstrated a maximum hydrogen storage capacity of 2.33 H/M(hydrogen atom/metal atom)at 723 K,with an enthalpy change(ΔH)of-141.09 kJ·mol^(-1)and an entropy change(ΔS)of-119.14 J·mol^(-1)·K^(-1).The kinetic mechanism of hydrogen absorption was hydride nucleation and growth,with an apparent activation energy(E_(a))of 20.90 kJ·mol^(-1).Without any activation,the YGdTbDyHo alloy could absorb hydrogen quickly(180 s at 923 K)with nearly no incubation period *** reason for the obtained value of 2.33 H/M was that the hydrogen atoms occupied both tetrahedral and octahedral *** results demonstrate the potential application of HEAs as a high-capacity hydrogen storage material with a large H/M ratio,which can be used in the deuterium storage field.

关键词： rare-earth high-entropy alloy hydrogen absorption capacity pressure–composition–temperature curves kinetics

Recent Advances in Fibrous Materials for Hydroelectricity Generation

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Nano-Micro Letters 2025年第2期17卷 109-133页

作者： Can Ge Duo Xu Xiao Feng Xing yang Zheheng song Yuhang song Jingyu Chen Yingcun Liu Chong Gao Yong Du Zhe Sun Weilin Xu Jian Fang College of Textile and Clothing Engineering Soochow UniversitySuzhou 215123People’s Republic of China National Engineering Laboratory for Modern Silk Soochow UniversitySuzhou 215123People’s Republic of China State Key Laboratory of New Textile Materials and Advanced Processing Technologies Wuhan Textile UniversityWuhan 430200People’s Republic of China Institute of Functional Nano&Soft Materials(FUNSOM) Soochow UniversitySuzhou 215123People’s Republic of China Department of Electrical and Computer Engineering University of MassachusettsAmherstMA 01003USA Department of Materials Imperial College LondonSouth Kensington CampusLondon SW72AZUK College of Textile Science and Engineering Zhejiang Sci-Tech UniversityHangzhou 310018People’s Republic of China School of Materials Science and Engineering Shanghai Institute of Technology100 Haiquan RoadShanghai 201418People’s Republic of China

Depleting fossil energy sources and conventional polluting power generation pose a threat to sustainable *** generation from ubiquitous and spontaneous phase transitions between liquid and gaseous water has been considered a promising strategy for mitigating the energy *** materials with unique flexibility,processability,multifunctionality,and practicability have been widely applied for fibrous materials-based hydroelectricity generation(FHG).In this review,the power generation mechanisms,design principles,and electricity enhancement factors of FHG are first ***,the fabrication strategies and characteristics of varied constructions including 1D fiber,1D yarn,2D fabric,2D membrane,3D fibrous framework,and 3D fibrous gel are ***,the advanced functions of FHG during water harvesting,proton dissociation,ion separation,and charge accumulation processes are analyzed in ***,the potential applications including power supply,energy storage,electrical sensor,and information expression are also ***,some existing challenges are considered and prospects for future development are sincerely proposed.

关键词： Hydroelectricity Fibrous material Streaming potential Ion diffusion

Synthesis and Antidiabetic Activity of Novelβ-amino Ketones Bearing 4-aminobenzoic acid and Nabumetone Moieties

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Synthesis and Antidiabetic Activity of Novelβ-amino Ketones...

Constructing quasi-2D perovskite to collect hot carriers to reduce open-circuit voltage loss for efficient inverted perovskite solar cells

2011年全国药物化学学术会议——药物的源头创新

作者： Guang-Xia Tang,Xiao-Li song,da-Cheng yang~* (School of Chemistry and Chemical Engineering,Southwest University,Chongqing 400715)

＜正＞Diabetes is a global burden and is rising all over the world due to various ***-2 diabetes mellitus（T2DM） is a chronic metabolic disorder that results from defects in both insulin secretion and insulin *** ava... 详细信息

关键词： diabetes mellitus θ-amino ketone nabumetone PPRE α-glucosidase

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Science China Chemistry 2025年

作者： Lei Gu Xing Li Chao Wu yang Feng Chunming yang Lin song Frontiers Science Center for Flexible Electronics Institute of Flexible Electronics Northwestern Polytechnical University Shanghai Synchrotron Radiation Facility Shanghai Advanced Research Institute Chinese Academy of Sciences

Inverted perovskite solar cells （PSCs） have received great attention owing to the high certificated power conversion efficiency（PCE） reaching 26.7%. However, interfacial charge recombination is far superior to perovskite bulk charge recombination due to the use of fullerenes and their derivatives in inverted perovskite solar cells, which induces devastating open circuit voltage（VOC） losses. For this reason the present work attempts to use 4-chloropiperidine hydrochloride for the upper surface modification of perovskite to construct a quasi-two-dimensional （2D） structure with suitable 2D layer widths （n=2, 3 dominant）,which has a smaller electron carrier transport barrier without sacrificing short-circuit current （JSC） in the device. This strategy effectively passivates the interfacial defect states while promoting energy level alignment to achieve carrier dissociation and equilibrium transport at the interface, which in turn resulted in improved fill factor （FF）. In addition, additional energy levels are provided by 2D perovskites to collect hot carriers, resulting in improved device open circuit voltage （VOC）. As a result, the device PCE increases from 22.37%to 24.11%after the 4CPD treatment. In addition, the 4CPD-treated PSCs maintain 90%of the initial PCE after storage in an N2atmosphere at 50°C for 1,080 h, whereas the control devices show a 15%PCE loss under the same aging conditions. This work provides new opportunities to suppress interfacial charge recombination in inverted devices.

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