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Megafossils of Betulaceae from the Oligocene of Qaidam Basin and their paleoenvironmental and phytogeographic implications

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Plant Diversity 2024年第1期46卷 101-115页

作者： tao Yang Jia-Hao Cai Yan-zhi dai Hong-Yu Chen Lei Han Li Zhang Wei-Yu Liang Xu-Jun Li Wen-Jia Li Jing-Yu Wu San-Ping Xie De-Fei Yan School of Earth Sciences and Key Laboratory of Mineral Resources in Western China(Gansu Province) Lanzhou UniversityLanzhou 730000China Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences Institute of Vertebrate Paleontology and PaleoanthropologyChinese Academy of SciencesBeijing 100044China State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology and Center for Excellence in Life and PaleoenvironmentChinese Academy of SciencesNanjing 210008China Center for Research and Education on Biological Evolution and Environments School of Earth Sciences and EngineeringNanjing UniversityNanjing 210023China

Understanding the paleoenvironment and phytogeographical history of the Tibetan Plateau,China relies on discovering new plant *** Qaidam Basin has long been regarded as an ideal‘field laboratory’to investigate the paleoclimate and paleobiological evolution of the northern Tibetan ***,fossil angiosperms from the Qaidam Basin are rare,and our knowledge of its paleovegetation is ***,we report fossil leaves and fruits of Betulaceae found from the Oligocene Shangganchaigou Formation of northwestern Qaidam Basin(Huatugou area).Comparative morphological analysis led us to assign the fruits to the Betula subgenus Betula and the leaves to Carpinus *** findings,together with other reported fossil plants from the same locality,reveal a close floristic linkage between the Qaidam Basin and Europe during the *** northern pathway of this floristic exchange may have crossed through the Qaidam Basin during the late *** floristic linkage may have been facilitated by the continuous narrowing of the Turgai Strait and stronger westerlies,which transported moisture and provided favorable climatic ***,fossil plants collected from the Qaidam Basin suggest that during the Oligocene this region had warm and humid deciduous broad-leaf forest,which differs from the region’s modern vegetation and indicates that the Qaidam Basin may have been a suitable region for these plants to flourish and spread during the Oligocene.

关键词： Paleoenvironment Biogeography Betulaceous fossil Qaidam basin Tibetan Plateau Oligocene

Measurement of Br(n,γ)cross sections up to stellar s-process temperatures at the CSNS Back‑n

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Nuclear Science and Techniques 2023年第11期34卷 226-241页

作者： Gao‑Le Yang Zhen‑Dong An Wei Jiang Xian‑Kai Li Wei‑Wei Qiu Zheng‑Fa Liao Zi‑Yue Zhuang Xiao‑Ping Zhang Sheng‑Li Chen Chen‑Chen Guo Er‑Xi Xiao Xiao Fang Xin‑Xiang Li Xin‑Rong Hu Bing Jiang Jin‑Cheng Wang Jie Ren Wen Luo zhi‑Chao Zhu Hao‑Yang Lan Zong‑Wei Cao Xu Ma Ying‑Du Liu Pu‑Sen Wang Yi Yang Ping Su Xian‑Gai Deng Wan‑Bing He Chun‑Wang Ma Yu‑Ting Wang zhi‑tao dai Peng‑Qin He Ren‑Guang Tang tao Zhou Jing Wang Han Yi Yue Zhang Yong‑Hao Chen Rui‑Rui Fan Ke‑Qing Gao Qiang Li Kang Sun zhi‑Xin Tan Min‑Hao Gu Han‑tao Jing Jing‑Yu Tang School of Physics and Astronomy Sun Yat-sen UniversityZhuhai 519082China Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China State Key Laboratory of Lunar and Planetary Sciences Macao University of Science and TechnologyMacao 999078China CNSA Macao Center for Space Exploration and Science Macao 999078China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China Spallation Neutron Source Science Center Dongguan 523803China School of Nuclear Science and Technology University of South ChinaHengyang 421001China Sino‑French Institute of Nuclear Engineering and Technology Sun Yat-sen UniversityZhuhai 519082China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Nuclear Data China Institute of Atomic EnergyBeijing 102413China School of Materials Science and Engineering Xiangtan UniversityXiangtan 411100China Key Laboratory of Nuclear Physics and Ion‑beam Application(MOE) Institute of Modern PhysicsDepartment of Nuclear Science and TechnologyFudan UniversityShanghai 200433China Institute of Particle and Nuclear Physics Henan Normal UniversityXinxiang 453007China School of Physics Henan Normal UniversityXinxiang 453007China Shenzhen Center Cancer hospitalChinese Academy of Medical SciencesShenzhen 518100China School of Nuclear Science and Technology University of Science and Technology of ChinaHefei 230027China

The neutron capture cross sections(n,γ)of bromine were obtained using the time-of-flight technique at the Back-n facility of the China Spallation Neutron ***γ-rays originating from neutron-induced capture events were detected using four C_(6)D_(6) *** pulse-height weighting technique and double-bunch unfolding method based on Bayesian theory were used in the data *** deductions,normalization,and corrections were carefully considered to obtain reliable measurement *** multilevel R-matrix Bayesian code SAMMY was used to extract the resonance parameters in the resolved resonance region(RRR).The average cross sections in the unresolved resonance region(URR)were obtained from 10 to 400 *** experimental results were compared with data from several evaluated libraries and previous experi-ments in the RRR and *** TALYS code was used to describe the average cross sections in the *** astrophysical Maxwell average cross sections(MACSs)of ^(79,81)Br from kT=5 to 100 keV were calculated over a sufficiently wide range of neutron *** a thermal energy of kT=30 keV,the MACS value for ^(79)Br 682±68 mb was in good agreement with the KADoNiS v1.0 recommended *** contrast,the value of 293±29 mb for ^(81)Br was substantially higher than that of the evaluated database and the KADoNiS v1.0 recommended value.

关键词： Time-of-flight technique Neutron capture cross sections Maxwell average cross sections

In-situ synthesis of quantum dots in the nucleus of live cells

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National Science Review 2024年第3期11卷 172-182页

作者： Yusi Hu zhi-Gang Wang Haohao Fu Chuanzheng Zhou Wensheng Cai Xueguang Shao Shu-Lin Liu dai-Wen Pang State Key Laboratory of Medicinal Chemical Biology Frontiers Science Centre for New Organic MatterTianjin Key Laboratory of Biosensing and Molecular Recognition Research Centre for Analytical Sciences College of Chemistry School of Medicine and Frontiers Science Centre for Cell Responses Nankai University Haihe Laboratory of Sustainable Chemical Transformations

The cell nucleus is the main site for the storage and replication of genetic material, and the synthesis of substances in the nucleus is rhythmic, regular and strictly regulated by physiological processes. However,whether exogenous substances, such as nanoparticles, can be synthesized in situ in the nucleus of live cells has not been reported. Here, we have achieved in-situ synthesis of CdSxSe1-xquantum dots（QDs） in the nucleus by regulation of the glutathione（GSH） metabolic pathway. High enrichment of GSH in the nucleus can be accomplished by the addition of GSH with the help of the Bcl-2 protein. Then, high-valence Se is reduced to low-valence Se by glutathione-reductase-catalyzed GSH, and interacts with the Cd precursor formed through Cd and thiol-rich proteins, eventually generating QDs in the nucleus. Our work contributes to a new understanding of the syntheses of substances in the cell nucleus and will pave the way for the development of advanced ‘supercells’.

关键词： glutathione live cell nucleus quantum dot intracellular synthesis

Prediction of suitable water content in granulation of sintering mixture based on Litster's model

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Journal of Iron and Steel Research(International) 2024年第3期31卷 552-560页

作者： Fang-lei dai Xiao-hui Fan Xiao-xian Huang Xu-ling Chen Min Gan zhi-yun Ji Zeng-qing Sun School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083HunanChina

Suitable water content plays a decisive role in the granulation of sintering ***,a method was proposed to predict the suitable water content for effective granulation on the basis of Litster's granulation *** granulation effectiveness of a sintering mixture was predicted by the model,with the allowance error of±10%.The effects of the water absorption properties,particle size composition and content of adhesive particles on the suitable water content were *** results showed that the allowable error of prediction was within±0.5%compared to the experimentally determined suitable water *** an increase in adhesive powder content of mixtures with higher water absorption,the suitable water content increased to achieve similar granulation ***,as the amount of concentrates increased,the suitable water content first increased and then remained *** influence of the water absorption characteristics of the adhesive particles on the suitable water content was less than that of their particle size composition in the mixture.

关键词： Adhesive particle Sintering mixture Granulation effectiveness Suitable water content

Stereospecific Assembly of Trisubstituted Alkenes via Photoinduced Nitrogen-Centered Radical-Triggered C—C Bond Cleavage/Functionalization of Oxime Esters

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Chinese Journal of Chemistry 2024年第12期42卷 1399-1406页

作者： Yu Bao zhi-Jie Song Jin-Long dai Shenghu Yan Yue Zhang Jia-Yin Wang Guigen Li School of Pharmacy Changzhou UniversityChangzhouJiangsu 213164China Department of Chemistry and Biochemistry Texas Tech University79409USA

Comprehensive Summary A general and convenient photoredox-catalyzed acylation and alkylcyanation of MBH acetates has been established,enabling the assembly of the C(sp2)–C(sp3)bond by a nitrogen-centered radical strategy for the synthesis of trisubstituted alkenes in moderate to excellent chemical yields(48 examples in total).The reaction of MBH acetates with acyl(indanone)oxime esters afforded trisubstituted alkenes containing 1,4-dicarbonyl ***,the use of Eosin Y as a photocatalyst in the catalytic system resulted in the formation of distal cyano group-anchored trisubstituted alkenes via deconstructive functionalization of cycloketone oxime ***,these resulting 1,4-dicarbonyl compounds could be applied to late-stage transformations,providing important methods for the synthesis of dihydropyridazin-3(2H)-one.

关键词： Photocatalysis Radical reactions MBH acetates Oxime esters Stereoselectivity Acylation Alkylation Green chemistry

Epidemiology and prognostic nomogram for locally advanced gastric signet ring cell carcinoma:A population-based study

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World Journal of Gastrointestinal Oncology 2024年第6期16卷 2610-2630页

作者： Ze-Hao Yu Lei-Ming Zhang zhi-Qi dai Meng-Na Zhang Si-Ming Zheng Health Science Center The First Affiliated Hospital of Ningbo UniversityNingbo 315000Zhejiang ProvinceChina Health Science Center Ningbo UniversityNingbo 315211Zhejiang ProvinceChina College of Medicine The First Affiliated Hospital of Zhejiang UniversityHangzhou 310058Zhejiang ProvinceChina

BACKGROUND Gastric signet ring cell carcinoma(GSRC)represents a specific subtype of gastric cancer renowned for its contentious epidemiological features,treatment principles,and prognostic *** To investigate the epidemiology of GSRC and establish an improved model for predicting the prognosis of patients with locally advanced GSRC(LAGSRC)after *** The annual rates of GSRC incidence and mortality,covering the years 1975 to 2019,were extracted from the Surveillance,Epidemiology,and End Results(SEER)database to explore the temporal trends in both disease incidence and mortality rates using Joinpoint *** clinical data of 3793 postoperative LAGSRC patients were collected from the SEER database for the analysis of survival *** Cox regression model was used to explore the independent prognostic factors for overall survival(OS).The risk factors extracted were used to establish a prognostic *** The overall incidence of GSRC increased dramatically between 1975 and 1998,followed by a significant downward trend in incidence after *** recent years,there has been a similarly optimistic trend in GSRC mortality *** trend in GSRC showed discrepancies based on age and *** operating characteristic curves,calibration curves,and decision curve analysis for 1-year,3-year,and 5-year OS demonstrated the high discriminative ability and clinical utility of this *** area under the curve indicated that the performance of the new model outperformed that of the pathological staging *** The model we established can aid clinicians in the early prognostication of LAGSRC patients,resulting in improved clinical outcomes by modifying management strategies and patient health care.

关键词： Signet ring cell carcinoma Locally advanced gastric cancer Adjuvant chemotherapy Nomogram Epidemiology Overall survival

Photodynamic eradication of intratumoral microbiota with bacteria-targeted micelles overcomes gemcitabine resistance of pancreatic cancer

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Aggregate 2024年第1期5卷 377-384页

作者： Renfa Liu Huanyu Yang Shuai Qu Peipei Yang Xin zhi Yunxue Xu zhifei dai Linxue Qian Department of Biomedical Engineering College of Future TechnologyNational Biomedical Imaging CenterPeking UniversityBeijingChina Department of Ultrasound Beijing Friendship HospitalCapital Medical UniversityBeijingChina

Increasing evidence suggests that intratumoral microbiota plays a pivotal role in tumor progression,immunosurveillance,metastasis,and ***,in pancreatic ductal adenocarcinoma,tumor-resident Gammaproteobacteria could transform the chemotherapeutic drug gemcitabine(Gem)into its inactive form,thus rendering chemotherapy ***,a strategy for selectively eradicating intratumoral bacteria was described for overcoming Gem resistance in a pancreatic cancer animal *** antimicrobial peptide was linked with photosensitizer through a poly(ethylene glycol)chain,which can self-assemble into micelles with a diameter of∼20 *** micelles could efficiently kill bacteria under light irradiation by inducing membrane depolarization,thereby inhibiting Gem *** a bacteria-resident pancreatic cancer animal model,the selective photodynamic eradication of intratumoral bacteria was demonstrated to efficiently reverse Gem *** research highlights antibacterial photodynamic therapy as a promising adjuvant strategy for cancer therapy by modulating intratumoral microbiota.

关键词： antimicrobial peptide gemcitabine resistance intratumoral microbiota pancreatic ductal adenocarcinoma photodynamic antibacterial therapy

Asymmetric side-chain engineering of organic semiconductor for ultrasensitive gas sensing

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Chinese Chemical Letters 2024年第3期35卷 428-433页

作者： Xiaoying Ma Xiaojuan dai Lanyi Xiang Jiajun Chang Danfeng zhi Haozhen Zhao Zhenjie Ni Ye Zou Xike Gao Fengjiao Zhang School of Chemical Sciences University of Chinese Academy of SciencesBeijing 100049China Laboratory of Organic Solids Institute of ChemistryChinese Academy of SciencesBeijing 100190China Key Laboratory of Synthetic and Self-Assembly Chemistry for Organic Functional Molecules Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China Binzhou Institute of Technology Binzhou 256606China

Molecular structure of organic semiconductor plays a critical role in determining the performance and functionality of organic electronic devices,by optimizing the electrical,optical and physicochemical *** alkyl chains are fundamental units in tailering the solubility and assemblability,among which the asymmetric properties have been reported as key element for controlling the packing motifs and intrinsic charge ***,we expanded the scope of molecular asymmetry dependent sensing features based on a new series of naphthalene diimides(NDI)-based derivatives substituted with a same branching alkyl chain but various linear-shaped alkyl chains(Cn-).A clear molecular stacking change,from head-to-head bilayer to head-to-tail monolayer packing model,is observed based on the features of anisotropic molecular interactions with the change in the chain *** importantly,a unique LUMO level shift of 0.17 eV is validated for NDI-PhC4,providing a record sensitivity up to 150%to 0.01 ppb ammonia,due to the desired molecular reactivity and device amplification *** results indicate that asymmetric side-chain engineering opens a route for breath healthcare.

关键词： Organic thin film transistor Asymmetric side chain Gas sensing Molecular stacking Energy level manipulating

Cytotoxinic Mechanism of Hydroxyapatite Nanoparticles on Human Hepatoma Cell Lines

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Journal of Wuhan University of Technology(Materials Science) 2003年第3期18卷 66-68页

作者：曹献英 Biomedical Material and Engineering Center Wuhan University of Technology

Stable and single dispersed HAP nanoparticles were synthesized with chemical method assisted by ultrasonic *** nanoparticles were surveyed by AFM and *** effect on the Bel-7402 human hepatoma cell lines treated with HAP nanoparticles was investigated by the MTT methods and observation of morphology,and the mechanism was studied in changes of cell cycle and *** result shows that inhibition of HAP nanoparticles on the Bel 7402 human hepatoma cell lines is obviously in *** nanoparticles the entered cancer cytoplasm,and cell proliferation is stopped at G 1 phase of cell cycle,thus,cancer cells die directly.

关键词： hydroxyapatite nanoparticles hepatocellular carcinoma tumor experiment