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Growth Behavior of Rubrene Thin Films on Hexagonal Boron Nitride in the Early Stage

Chinese Journal of Chemistry 2022年第11期40卷 1298-1304,I0002页

作者： Yujia Wei Di Xue Lianlian Ji Jie Lu qi wang Xingyu Jiang Yinghui Sun zi wang Lizhen Huang Lifeng Chi Institute of Functional Nano&Soft Materials(FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials&DevicesCollaborative Innovation Center of Suzhou Nano Science and TechnologySoochow UniversitySuzhouJiangsu 215123China College of Energy Soochow Institute for Energy and Materials InnovationsKey Laboratory of Advanced Carbon Materials and Wearable Energy Technologies of Jiangsu ProvinceSoochow UniversitySuzhouJiangsu 215006China Gusu Laboratory of Materials SuzhouJiangsu 215123China

Two-dimensional materials,with an in-plane ordered and dangling-bonding-free surface,are ideal substrates for fabricating high-quality crystalline thin films.Here,we show a systematic study on the growth of a benchmark organic semiconductor,rubrene,on hexagonal boron nitride(h-BN)substrate via physical vapor deposition from the initial amorphous phase to the final crystalline phase;the role of temperature in such transition and the epitaxy relationship between rubrene and h-BN are revealed.With the increase of substrate temperature,the critical thickness of amorphous-crystalline-transition decreases and the morphology of crystalline phase also evolves from porous to terrace-like.When substrate temperature reaches>100℃,the critical thickness reduces to only 0.5 nm and a precise layer-by-layer growth from the very first layer is achieved,which is quite rare for rubrene growing on other substrates.The high ordering can be attributed to the fine epitaxy relationship between rubrene films and the h-BN surface lattice,and this film demonstrates good charge transport ability with a p-type field-effect mobility of>1 cm^(2)·V^(-1)·s^(-1).

关键词： Thin films Crystal growth Organic thin film transistors 2D materials Molecular electronics

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Visualizing the dynamic progression of backward erosion piping in a Hele-Shaw cell

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2022年第11期23卷 945-954页

作者： Gang ZHENG Jing-bo TONG Tian-qi ZHANG zi-wu wang Xun LI Ji-qing ZHANG Chun-yu qi Hai-zuo ZHOU Yu DIAO MOE Key Laboratory of Coast Civil Structure Safety Tianjin UniversityTianjin 300072China School of Science Tianjin UniversityTianjin 300072China China Railway Design Corporation Tianjin 300308China National Engineering Laboratory for Digital Construction and Evaluation Technology of Urban Rail Transit Tianjin 300308China

With the utilization of underground space,backward erosion piping(BEP)has been observed in many underground structures(e.g.,shield tunnels)founded on sandy aquifers.However,due to invisibility,the geometry of the eroded pipe and its spatial evolution with time during the piping process was still not clear.In this study,we developed a Hele-Shaw cell to visualize the dynamic progression of BEP.With imaging process technology,we obtained a typical process of BEP(the erosion process can be divided into a piping progression phase and a piping stabilization phase),quantitatively characterized the formation of erosion pipes,and compared the patterns of erosion(e.g.,the erosion area A and the maximum erosion radius R)that spontaneously develop under different fluxes of water.The most interesting finding is that the sand grains in a thicker Hele-Shaw model are easier to dislodge,which is possibly due to the granular system in a thicker model having more degrees of freedom,reducing the stability of the sand grains.

关键词： Backward erosion piping(BEP) Dynamic progression Hele-Shaw cell Visualize Imaging processing technology

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Asymmetric discriminative correlation filters for visual tracking

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Frontiers of Information Technology & Electronic Engineering 2020年第10期21卷 1467-1484页

作者： Shui-wang LI qian-bo JIANG qi-jun ZHAO Li LU zi-liang FENG National Key Laboratory of Fundamental Science on Synthetic Vision College of Computer ScienceSichuan UniversityChengdu 610065China

Discriminative correlation filters(DCF)are efficient in visual tracking and have advanced the field significantly.However,the symmetry of correlation(or convolution)operator results in computational problems and does harm to the generalized translation equivariance.The former problem has been approached in many ways,whereas the latter one has not been well recognized.In this paper,we analyze the problems with the symmetry of circular convolution and propose an asymmetric one,which as a generalization of the former has a weak generalized translation equivariance property.With this operator,we propose a tracker called the asymmetric discriminative correlation filter(ADCF),which is more sensitive to translations of targets.Its asymmetry allows the filter and the samples to have different sizes.This flexibility makes the computational complexity of ADCF more controllable in the sense that the number of filter parameters will not grow with the sample size.Moreover,the normal matrix of ADCF is a block matrix with each block being a two-level block Toeplitz matrix.With this well-structured normal matrix,we design an algorithm for multiplying an N×N two-level block Toeplitz matrix by a vector with time complexity O(N log N)and space complexity O(N),instead of O(N^2).Unlike DCF-based trackers,introducing spatial or temporal regularization does not increase the essential computational complexity of ADCF.Comparative experiments are performed on a synthetic dataset and four benchmarks,including OTB-2013,OTB-2015,VOT-2016,and Temple-Color,and the results show that our method achieves state-of-the-art visual tracking performance.

关键词： Visual tracking Discriminative correlation filter(DCF) Asymmetric DCF(ADCF)

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Chemistry and bioactivities of natural steroidal alkaloids

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Natural Products and Bioprospecting 2022年第1期12卷 310-359页

作者： Mei-Ling Xiang Bin-Yuan Hu zi-Heng qi Xiao-Na wang Tian-Zhen Xie Zhao-Jie wang Dan-Yu Ma qi Zeng Xiao-Dong Luo Key Laboratory of Medicinal Chemistry for Natural Resource Ministry of EducationYunnan Provincial Center for Research&Development of Natural ProductsSchool of Chemical Science and TechnologyYunnan UniversityKunming 650091People’s Republic of China State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of SciencesKunming 650201People’s Republic of China

Steroidal alkaloids possess the basic steroidal skeleton with a nitrogen atom in rings or side chains incorporated as an integral part of the molecule.They have demonstrated a wide range of biological activities,and some of them have even been developed as therapeutic drugs,such as abiraterone acetate(Zytiga®),a blockbuster drug,which has been used for the treatment of prostate cancer.Structurally diverse natural steroidal alkaloids present a wide spectrum of biological activities,which are attractive for natural product chemistry and medicinal chemistry communities.This review comprehensively covers the structural classification,isolation and various biological activities of 697 natural steroidal alkaloids discovered from 1926 to October 2021,with 363 references being cited.

关键词： Steroidal alkaloids Chemistry Bioactivities Solanaceae Liliaceae Apocynaceae Buxaceae

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Stimulating factors for regulation of osteogenic and chondrogenic differentiation of mesenchymal stem cells

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World Journal of Stem Cells 2023年第5期15卷 369-384页

作者： Jia-qi Zhou Hao-Yang Wan zi-Xuan wang Nan Jiang Division of Orthopaedics and Traumatology Department of OrthopaedicsNanfang HospitalSouthern Medical UniversityGuangzhou 510515Guangdong ProvinceChina

Mesenchymal stem cells(MSCs),distributed in many tissues in the human body,are multipotent cells capable of differentiating in specific directions.It is usually considered that the differentiation process of MSCs depends on specialized external stimulating factors,including cell signaling pathways,cytokines,and other physical stimuli.Recent findings have revealed other underrated roles in the differentiation process of MSCs,such as material morphology and exosomes.Although relevant achievements have substantially advanced the applicability of MSCs,some of these regulatory mechanisms still need to be better understood.Moreover,limitations such as long-term survival in vivo hinder the clinical application of MSCs therapy.This review article summarizes current knowledge regarding the differentiation patterns of MSCs under specific stimulating factors.

关键词： Mesenchymal stem cells Differentiation Osteogenic Chondrogenic Literature review

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One-stage total hip arthroplasty and“light-bulb”procedure for bilateral non-traumatic osteonecrosis of femoral head in different stages

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Chinese Medical Journal 2019年第23期132卷 2883-2885页

作者： Pei Liu qi-Dong Zhang Yang wang zi-qi Xia Fei-Fan Lu Zhao-Hui Liu Wei-Guo wang Wan-Shou Guo Beijing University of Chinese Medicine Beijing 100029China Department of Orthopedic Surgery Beijing Key Lab Immune-Mediated Inflammatory DiseasesChina-Japan Friendship HospitalBeijing 100029China China-Japan Friendship School of Clinical Medicine Peking UniversityBeijing 100029China

To the Editor:Clinically,it is not rare for patients with bilateral non-traumatic osteonecrosis of femoral head(NONFH)first presenting to an orthopedic surgeon with one hip that requires total hip arthroplasty(THA)and... 详细信息

关键词： femoral traumatic arthroplasty

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Microporous Organic Nanotube Networks from Hyper Cross-linking Core-shell Bottlebrush Copolymers for Selective Adsorption Study

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Chinese Journal of Polymer Science 2018年第1期36卷 98-105页

作者： Tian-qi wang Yang Xu zi-Dong He Ming-Hong Zhou Kun Huang School of Chemistry and Molecular Engineering East China Normal University

We report a synthesis of microporous organic nanotube networks（MONNs） by a combination of hyper cross-linking and molecular templating of core-shell bottlebrush copolymers. The intrabrush and interbrush cross-linking of polystyrene（PS） shell layer in the core-shell bottlebrush copolymers led to the formation of micropores and large-sized nanopores（meso/macrospores） in MONNs, respectively, while selective removal of polylactide（PLA） core layer generated mesoporous tubular structure. The size of PLA-templated mesoporous cores and porous structure both at micro-and meso-scale could be controlled by simple tuning of the ratio of core/shell or the PLA core fraction in the bottlebrush precursors. Moreover, the resultant MONNs showed a highly selective adsorption capacity for the positively charged dyes on the basis of multi-porosity and carboxylate group-rich structure. In addition, MONNs also exhibited effective performance in size-selective adsorption of biomacromolecules. This work represents a new avenue for the preparation of MONNs and also provides a new application for molecular bottlebrushes in nanotechnology.

关键词： Microporous organic nanotube networks Hyper cross-linking Core-shell bottlebrush copolymers Meso/Macrospores Selective adsorption capacity

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Formation of multiple trimethylsilyl derivatives in the derivatization of 17α-ethinylestradiol with BSTFA or MSTFA followed by gas chromatography-mass spectrometry determination

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Journal of Environmental Sciences 2007年第7期19卷 879-884页

作者： ZHOU Yi-qi wang zi-jian JIA Ning Sate Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China. College of Environment and Energy Engineering Beijing University of Technology Beijing 100022 China

N,O-bis（trimethylsily）trifluoroacetamide （BSTFA） and N-methyl-N（trimethylsily） trifluoroacetamide （MSTFA） are common derivatization reagents used in the GC-MS analysis of estrogen steroids such as estrone （El） and 17α-ethinylestradiol （EE2）. In this study, three trimethylsilyl （TMS） steroid derivatives, mono- and di-trimethylsilyl EE2 and mono-trimethylsilyl El, were observed during the derivatization of EE2 with BSTFA or MSTFA and/or GC separation. Factors influencing the production of multiple TMS derivatives and their relative abundance were examined. It was found that both methanol and bisphenol A competed with estrogenic esteroids when reacting with silylation reagents, and thus affected the formation of TMS derivatives and their relative abundance in the derivatization products. Methanol was found to be more reactive than bisphenol A with the BSTFA reagent. None of the three solvents tested in this study could prevent the generation of multiple TMS derivatives during the derivatization of EE2 with BSTFA, followed by GC analysis. A similar result was observed using MSTFA as the derivative reagent followed by GC analysis. Thus, the suitability of BSTFA or MSTFA as the derivatization reagent for the determination of E1 and EE2 by GC-MS, under the conditions reported here, is questionable. This problem can be solved by adding trimethylsilylimidaz （TMSI） in the BSTFA reagent as recommended, and the performance of the method has been proved in this study.

关键词： estrogens water sample GC/MS determination trimethylsilyl steroid derivatives

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Tributary Medicine System of the qing Dynasty: A Preliminary Study

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Chinese Medicine and Culture 2022年第1期5卷 23-30页

作者： zi-Long Zhang Yi-Sha Xian Xiao-Jie Shi Xue-qi wang Ling-Yi Sun School of Chinese Materia Medica Beijing University of Chinese MedicineBeijing 102488China School of Traditional Chinese Medicine Beijing University of Chinese MedicineBeijing 102488China

Medicine was one of the articles of tribute paid by other countries and kingdoms to the imperial court of the qing dynasty(1644–1912).The act of paying tributes and the rituals associated with it enhanced communication and helped establish relationships between ancient China and other nations or territories.The imperial court was generous in return,which attracted many countries to pay tributes.This paper analyzes how medicines as tributes played an important role in consolidating the dominant status of ancient China,and in promoting the exchange of knowledge between Chinese and Western medicine.

关键词： Sino-westem interaction Medical knowledge exchange Medicine as tribute qing dynasty Suzerain-vassal relationship

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Apelin-13 inhibits apoptosis and excessive autophagy in cerebral ischemia/reperfusion injury

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Neural Regeneration Research 2021年第6期16卷 1044-1051页

作者： zi-qi Shao Shan-Shan Dou Jun-Ge Zhu Hui-qing wang Chun-Mei wang Bao-Hua Cheng Bo Bai Cheeloo College of Medicine Shandong UniversityJinanShandong ProvinceChina Neurobiology Institute Jining Medical UniversityJiningShandong ProvinceChina

Apelin-13 is a novel endogenous ligand for an angiotensin-like orphan G-protein coupled receptor,and it may be neuroprotective against cerebral ischemia injury.However,the precise mechanisms of the effects of apelin-13 remain to be elucidated.To investigate the effects of apelin-13 on apoptosis and autophagy in models of cerebral ischemia/reperfusion injury,a rat model was established by middle cerebral artery occlusion.Apelin-13(50μg/kg)was injected into the right ventricle as a treatment.In addition,an SH-SY5Y cell model was established by oxygen-glucose deprivation/reperfusion,with cells first cultured in sugar-free medium with 95%N2 and 5%CO2 for 4 hours and then cultured in a normal environment with sugar-containing medium for 5 hours.This SH-SY5Y cell model was treated with 10-7 M apelin-13 for 5 hours.Results showed that apelin-13 protected against cerebral ischemia/reperfusion injury.Apelin-13 treatment alleviated neuronal apoptosis by increasing the ratio of Bcl-2/Bax and significantly decreasing cleaved caspase-3 expression.In addition,apelin-13 significantly inhibited excessive autophagy by regulating the expression of LC3B,p62,and Beclin1.Furthermore,the expression of Bcl-2 and the phosphatidylinositol-3-kinase(PI3K)/Akt/mammalian target of rapamycin(mTOR)pathway was markedly increased.Both LY294002(20μM)and rapamycin(500 nM),which are inhibitors of the PI3K/Akt/mTOR pathway,significantly attenuated the inhibition of autophagy and apoptosis caused by apelin-13.In conclusion,the findings of the present study suggest that Bcl-2 upregulation and mTOR signaling pathway activation lead to the inhibition of apoptosis and excessive autophagy.These effects are involved in apelin-13-induced neuroprotection against cerebral ischemia/reperfusion injury,both in vivo and in vitro.The study was approved by the Animal Ethical and Welfare Committee of Jining Medical University,China(approval No.2018-JS-001)in February 2018.

关键词： central nervous system brain brain injury factor pathways apoptosis autophagy neuroprotection regeneration

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