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Two novel aconane-type diterpenes derived from C-nor-C_(19)-diterpenoid alkaloid

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Chinese Chemical Letters 2009年第4期20卷 431-434页

作者： Xiang Li Shen Qiao Hong chen dong lin chen Feng Peng Wang Department of Chemistry of Medicinal Natural Products West China College of Pharmacy Sichuan University Chengdu 610041 China Second Hospital of Sichuan University Chengdu 610041 China

Two novel C-nor-B-homo aconane-type diterpenes 4 and 5, featuring a unique eight-membered ring system, were obtained by the treatment of C-nor-C19-diterpenoid alkaloid 3 with HNO2 in 8% and 21% yields, respectively. Structures of these two compounds were established based on the combination of spectroscopic data, including HRESIMS, 1D and 2D NMR data. A olausible mechanism for the formation of 4 and 5 is also presented.

关键词： C19-diterpenoid alkaloid C-nor-B-homo-aconane Rearrangement Imine

Realizing the excellent oxidation resistance of an environmental barrier coating through aluminum surface modification

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Journal of Advanced Ceramics 2024年第7期13卷 976-986页

作者： lin dong Wen-Qi Yang lin chen Guan-Jun Yang Chang-Jiu Li State Key Laboratory for Mechanical Behavior of Materials School of Materials Science and EngineeringXi’an Jiaotong UniversityXi’an 710049China Xi’an Aerospace Engine Company Limited in China Aerospace Science and Technology Corporation Xi’an 710065China

The lifetime of Si-based environmental barrier coatings(EBCs)is constrained by thermally grown SiO_(2)oxidelayer(SiO_(2)-TGO),which can cause premature cracking and *** address this issue,a new approach for surfacemodification using aluminum is *** oxidation performance was examined in a 50 vol%H_(2)O-50 vol%O_(2)environment at 1350℃for up to 300 *** results indicate that a dense ytterbium aluminum garnet(YbAG)layer wasformed after modification,decreasing the porosity by 80%.Due to the elimination of fast diffusion channels and the lowoxygen permeability of YbAG,aluminum modification significantly reduced the growth rate of SiO_(2)-TGO by nearly twoorders of ***,its thickness decreased by more than 70%after 300 h of exposure.A diffusioncontrolled oxidation mechanism indicates that the modified dense surface is equivalent to an initial SiO_(2)layer with a specificthickness,causing a shift in the oxidation time and increasing the oxidation *** research provides valuableinsights for designing Si-based EBC with improved lifetimes.

关键词： environmental barrier coating(EBC) oxidation modification diffusion cracking

Selective photosynthesis of imines from biomass-derived aldehydes over Ni/TiO_(2)

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Rare Metals 2024年第3期43卷 1116-1124页

作者： Wu-lin Li Qing-Qing Zhang lin dong Wen-Jun Zhang Li-Li lin Zu-Peng chen Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources International Innovation Center for Forest Chemicals and MaterialsCollege of Chemical EngineeringNanjing Forestry UniversityNanjing210037China Institute of Industrial Catalysis State Key Laboratory of Green Chemistry Synthesis TechnologyCollege of Chemical EngineeringZhejiang University of TechnologyHangzhou310014China

Photocatalytic reductive amination of biomass-derived aldehydes is a desirable way to selectively upgrade biomass into value-added nitrogen-containing chemicals under mild ***,it is challenging to produce imines in high selectivity because of the undesirable side reactions caused by the activity of functional ***,we demonstrate the highly reactive and selective production of imines from biomass derived aldehydes via the photocatalytic reductive amination,using a defective TiO_(2)supported nickel *** employment of methanol as the hydrogen donor and ammonia solution as the nitrogen source avoids the use of high-pressure H_(2)and expensive amines,rendering the current catalytic process safe,economical,and environmentally *** depth investigations attribute the improved separation and transfer of photogenerated charge carriers to the presence of oxygen vacancies and decorated Ni nanoparticles,thereby accelerating the production of imines from benzaldehyde amination(conversion,95.8%;seleetivity,95.2%).Furthermore,the developed system could be easily translated to the photocatalytic conversions of various biomass derived aldehydes,which provided an example of a cost-effective and sustainable approach for the valorization of biomass derived feedstocks.

关键词： Photocatalysis Biomass derivatives Imines Reduction amination Heterogeneous catalyst

Efficient removal of natural organo-chromium(Ⅲ)through selfcirculating decomplex and immobilization with nanoscale zerovalent iron

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Nano Research 2024年第1期17卷 364-371页

作者： Zhicheng dong Yunyun Xu Can Wu Jin Chao chen Tian Zhang lin School of Metallurgy and Environment Central South UniversityChangsha 410083China Chinese National Engineering Research Center for Control&Treatment of Heavy Metal Pollution Changsha 410083China College of Ecology and Environment Chengdu University of TechnologyChengdu 610059China School of Environment and Energy The Key Laboratory of Pollution Control and Ecosystem Restoration in Industry Clusters(Ministry of Education)South China University of TechnologyGuangzhou 510006China

Organo-chromium(III)complex is one of the chromium contaminant species,which would transform to high-toxic Cr(VI)during migrating in the *** natural organo-chromium(III)(NOCr)is difficult to remove by traditional degradation or precipitation methods,due to its high stability and ***,we demonstrated a novel NOCr removing method by transforming it to certain structures similar to Cr-Fe minerals in nature,through a self-circulating decomplex and immobilization mechanism with nano zero-valent iron(nZVI).Taking chromium glycinate(Cr-Gly)as a probe,nZVI showed a high Cr removal efficiency of 99.4%under ambient *** removal process included three stages of adsorption,decomplexation,and ***-Gly was first adsorbed on the surface of nZVI by chemisorption of the oxide ***,the adsorbed Cr-Gly was decomplexed and oxidized to Cr(VI)by·OH and 1O_(2),which were generated from molecular oxygen activated by ***,the released Cr(VI)could be in-situ adsorbed and re-reduced to Cr(III),which was further immobilized in form of Cr-O-Fe *** the Cr-O-Fe complexing structure was similar to that of Cr-Fe minerals(such as chromohercynite)in nature,this work explored a novel and efficient NOCr removing method that was potential to weaken chromium pollution in the environment.

关键词： organo-chromium(III) zero-valent iron adsorption decomplexation Cr immobilization

Impact of Alcian blue and periodic acid Schiff expression on the prognosis of gastric signet ring cell carcinoma

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World Journal of Gastrointestinal Oncology 2024年第3期16卷 687-698页

作者： Juan lin Zhu-Feng chen Guo-dong Guo Xin chen Shengli Clinical Medical College Fujian Medical UniversityFuzhou 350001Fujian ProvinceChina Department of Pathology Fujian Provincial HospitalFuzhou 350001Fujian ProvinceChina Department of Internal Medicine Fujian Provincial HospitalFuzhou 350001Fujian ProvinceChina

BACKGROUND The Alcian blue(AB)and periodic acid Schiff(PAS)stains are representative mucus markers in gastric signet ring cell carcinoma(SRCC).They are low-cost special staining methods used to detect acidic mucus and neutral mucus,***,the clinical importance of the special combined AB and PAS stain is *** To investigate AB expression,PAS expression and the AB-to-PAS(A/P)ratio in gastric SRCC patients and to assess patient *** Paraffin-embedded sections from 83 patients with gastric SRCC were stained with AB and PAS,and signet ring cell positivity was assessed ***-histochemical staining for Ki67,protein 53(P53)and human epidermal growth factor receptor 2(HER2)was performed *** cancer-specific survival(CSS)rate was estimated via Kaplan-Meier *** proportional hazards models were used for univariate and multivariate survival *** Kaplan-Meier survival analysis revealed that the 3-year CSS rate was significantly greater in the high-PAS-expression subgroup than in the low-PAS-expression subgroup(P0.5 group(P=0.042).Univariate Cox regression analysis revealed that the factors affecting prognosis included tumor diameter,lymph node metastasis,vessel carcinoma embolus,tumor stage,the A/P ratio and the expression of Ki67,P53 and the *** multivariate regression analysis confirmed that low PAS expression[hazard ratio(HR)=3.809,95%confidence interval(CI):1.563-9.283,P=0.003]and large tumor diameter(HR=2.761,95%CI:1.086-7.020,P=0.033)were independent risk factors for poor *** A/P>0.5 is potentially a risk factor for prognosis,and low PAS expression is an independent risk factor in the prognosis of gastric *** expression and the A/P ratio could help in predicting the clinical prognosis of patients with SRCC.

关键词： Alcian blue Periodic acid-Schiff Prognosis Gastric Signet ring cell carcinoma

New C_(20)-diterpenoid alkaloids from Aconitum sinomontanum

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Chinese Chemical Letters 2016年第5期27卷 761-763页

作者： Hua Tang Fu-Li Wen Shu-He Wang Xiao-Yu Liu dong-lin chen Feng-Peng Wang Department of Chemistry of Medicinal Natural Products West China College of Pharmacy Sichuan University

Two new denudatine-type C20-diterpenoid alkaloids, named sinomontanidines A （1） and B （2）, were isolated from the roots ofAconitum sinomontanum Nakai. Their structures were elucidated by extensive analysis of 1D, ... 详细信息

关键词： Diterpenoid alkaloid Sinomontanidine Denudatine Aconitum sinomontanum Ranunculaceae

Memory-enhanced text style transfer with dynamic style learning and calibration

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Science China(Information Sciences) 2024年第4期67卷 181-196页

作者： Fuqiang lin Yiping SONG Zhiliang TIAN Wangqun chen Diwen dong Bo LIU College of Computer Science and Technology National University of Defense Technology Department of Computer Science and Engineering The Hong Kong University of Science and Technology Strategic Assessments and Consultation Institute Academy of Military Sciences

Text style transfer aims to rephrase a sentence to match the desired style while retaining the original content. As a controllable text generation task, mainstream approaches use content-independent style embedding as control variables to guide stylistic generation. Nonetheless, stylistic properties are contextsensitive even under the same style. For example, “delicious” and “helpful” convey positive sentiments,although they are more likely to describe food and people, respectively. Therefore, desired style signals must vary with the content. To this end, we propose a memory-enhanced transfer method, which learns fine-grained style representation concerning content to assist transfer. Rather than employing static style embedding or latent variables, our method abstracts linguistic characteristics from training corpora and memorizes subdivided content with the corresponding style representations. The style signal is dynamically retrieved from memory using the content as a query, providing a more expressive and flexible latent style space. To address the imbalance between quantity and quality in different content, we further introduce a calibration method to augment memory construction by modeling the relationship between candidate *** results obtained using three benchmark datasets confirm the superior performance of our model compared to competitive approaches. The evaluation metrics and case study also indicate that our model can generate diverse stylistic phrases matching context.

关键词： style transfer memory-enhanced method text generation deep learning text representation

Azocalixarenes: a scaffold of universal excipients with high efficiency

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Science China Chemistry 2024年第5期67卷 1697-1706页

作者： Yu-Xin Yue Yi-lin lin Meng-Meng chen Han-Wen Tian Rong Ma Ze-Han Wang Fang-Yuan chen Yu-chen Pan dong-Sheng Guo College of Chemistry State Key Laboratory of Elemento-Organic ChemistryKey Laboratory of Functional Polymer Materials(Ministry of Education)Frontiers Science Center for New Organic MatterCollaborative Innovation Center of Chemical Science and Engineering(Tianjin)Nankai UniversityTianjin 300071China

Excipients are important components of pharmaceutical preparations that affect their quality, safety, and efficacy. Macrocyclic receptors are a family of supramolecular excipients with several advantages, including molecular-level protection, small sizes,fast kinetics of host-guest recognition, and modular construction. With the continuous advances in the medical field, personalized and precision medicine requires the development of excipients with low dosages, integrated modifying effects, universality,and controlled release. To meet these requirements, we have developed a new family of macrocyclic excipients based on calixarenes by integrating their covalent(broad chemical design space) and noncovalent(wide range of substrates) ***, azocalixarenes(Azo CAs) were designed, showing high binding affinities to a broad spectrum of active pharmaceutical ingredients(APIs), selectivity to interferents, and responsiveness to hypoxic microenvironments. Due to their highly efficient and controllable recognition, Azo CAs serve as low-dose excipients for 30 APIs. Molecular encapsulation by Azo CAs results in the integrated modification of the physicochemical properties of APIs, including solubility, stability, bioavailability,and biocompatibility. Moreover, Azo CAs can be reduced by azoreductases overexpressed in hypoxic microenvironments,leading to the controlled release of APIs. Collectively, Azo CA excipients have broad application prospects for a series of diseases such as enteritis, arthritis, stroke, cancer, bacterial infection and kidney injury, with diverse therapeutic modalities,including chemotherapy, photodynamic therapy, photothermal therapy, immunotherapy, boron neutron capture therapy, radiotherapy, fluorescence imaging, and their combinations.

关键词： supramolecular chemistry host-guest systems excipient calixarene molecular recognition

Flower development and sexual dimorphism in Vernicia montana

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Horticultural Plant Journal 2024年第2期10卷 586-600页

作者： Wenying Li Jingzhen chen Xiang dong Meilan Liu Guibin Wang lin Zhang Key Laboratory of Cultivation and Protection for Non-wood Forest Trees Ministry of EducationCentral South University of Forestry and TechnologyChangshaHunan 410004China State Key Laboratory of Utilization of Woody Oil Resource Hunan Academy of ForestryChangshaHunan 410004China College of Forestry Nanjing Forestry UniversityNanjingJiangsu 210037China

The mu oil tree(Vernicia montana Lour.) is a dioecious species, but the genetic mechanisms underlying its phenotypic sexual dimorphism are unclear. In this study, we determined two pivotal phases of sex differentiation of mu oil tree via morphological and histological analyses of unisexual flowers:(Ⅰ) differentiation of male or female primordia to produce staminate flowers(SFs) or transient hermaphrodite flowers(HFs),and(Ⅱ) complete abortion of stamens in transient HFs to generate pistillate flowers(PFs). A total of 1621 sex-biased genes were identified by comparative transcriptome analysis which exhibited elevated rates of protein evolution than unbiased genes. The female-biased genes were enriched in the production of defense compounds while male-biased genes were focused on the production of viable pollens. Transcriptomebased analysis revealed that the differentially expressed genes(DEGs) between PFs and SFs in phase Ⅰ involved in abscisic acid(ABA), auxin(AUX), cytokinin(CK), ethylene(ET), and gibberellin(GA) biosynthesis and signaling showed higher expression levels in males than in females in general, whereas the DEGs involved in jasmonic acid(JA) and salicylic acid(SA) pathways displayed opposite expression patterns. Moreover,differentially expressed endogenous ABA, AUX, GAs, JA, and SA exhibited consistent biased expression patterns with the DEGs by UPLC-MSbased analysis. Exogenous application of an anti-ethylene plant growth regulator could promote the development of stamens in PFs and generated HFs. Comparative transcriptomic and hormonal analyses of PFs and SFs in phase Ⅱ indicated an increase in ET concentration when abortion of stamens in PFs occurred. This study suggested that phytohormones play key roles in sex dimorphism and ET may determine the development of stamens in PFs of mu oil tree, which provides an insight into plant sex differentiation mechanisms.

关键词： Mu oil tree Flower development Sexual dimorphism Sex bias Ethylene