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Observation of flat-band localized state in a one-dimensional diamond momentum lattice of ultracold atoms
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作者 曾超 石悦然 +5 位作者 毛一屹 武菲菲 谢岩骏 苑涛 戴汉宁 陈宇翱 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期212-217,共6页
We investigated the one-dimensional diamond ladder in the momentum lattice platform. By inducing multiple twoand four-photon Bragg scatterings among specific momentum states, we achieved a flat band system based on th... We investigated the one-dimensional diamond ladder in the momentum lattice platform. By inducing multiple twoand four-photon Bragg scatterings among specific momentum states, we achieved a flat band system based on the diamond model, precisely controlling the coupling strength and phase between individual lattice sites. Utilizing two lattice sites couplings, we generated a compact localized state associated with the flat band, which remained localized throughout the entire time evolution. We successfully realized the continuous shift of flat bands by adjusting the corresponding nearest neighbor hopping strength, enabling us to observe the complete localization process. This opens avenues for further exploration of more complex properties within flat-band systems, including investigating the robustness of flat-band localized states in disordered flat-band systems and exploring many-body localization in interacting flat-band systems. 展开更多
关键词 diamond lattice flat band momentum lattice localized state
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Age-related secretion of grancalcin by macrophages induces skeletal stem/progenitor cell senescence during fracture healing
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作者 Nan-Yu Zou Ran Liu +18 位作者 Mei Huang Yu-Rui Jiao Jie Wei Yangzi Jiang Wen-Zhen He Min Huang Yi-Li Xu Ling Liu Yu-Chen Sun Mi Yang Qi Guo Yan Huang Tian Su Ye Xiao Wei-Shan Wang chao zeng Guang-Hua Lei Xiang-Hang Luo Chang-Jun Li 《Bone Research》 SCIE CAS CSCD 2024年第1期122-136,共15页
Skeletal stem/progenitor cell(SSPC)senescence is a major cause of decreased bone regenerative potential with aging,but the causes of SSPC senescence remain unclear.In this study,we revealed that macrophages in calluse... Skeletal stem/progenitor cell(SSPC)senescence is a major cause of decreased bone regenerative potential with aging,but the causes of SSPC senescence remain unclear.In this study,we revealed that macrophages in calluses secrete prosenescent factors,including grancalcin(GCA),during aging,which triggers SSPC senescence and impairs fracture healing.Local injection of human rGCA in young mice induced SSPC senescence and delayed fracture repair.Genetic deletion of Gca in monocytes/macrophages was sufficient to rejuvenate fracture repair in aged mice and alleviate SSPC senescence.Mechanistically,GCA binds to the plexin-B2 receptor and activates Arg2-mediated mitochondrial dysfunction,resulting in cellular senescence.Depletion of Plxnb2 in SSPCs impaired fracture healing.Administration of GCA-neutralizing antibody enhanced fracture healing in aged mice.Thus,our study revealed that senescent macrophages within calluses secrete GCA to trigger SSPC secondary senescence,and GCA neutralization represents a promising therapy for nonunion or delayed union in elderly individuals. 展开更多
关键词 healing UNION SENESCENCE
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Clinicopathological analysis of EWSR1/FUS::NFATC2 rearranged sarcoma in the left forearm:A case report
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作者 Qiao-Ling Hu chao zeng 《World Journal of Clinical Cases》 SCIE 2024年第16期2887-2893,共7页
BACKGROUND We present a case of an EWSR1/FUS::NFATC2 rearranged sarcoma in the left forearm and analyze its clinicopathological and molecular features.CASE SUMMARY The patient is a 23-year-old woman.Microscopically,th... BACKGROUND We present a case of an EWSR1/FUS::NFATC2 rearranged sarcoma in the left forearm and analyze its clinicopathological and molecular features.CASE SUMMARY The patient is a 23-year-old woman.Microscopically,the tumor cells were medium-sized round cells arranged in small nests.The cytoplasm was clear,nuclei were relatively uniform,chromatin was dense,nucleoli were visible,and mitotic figures were rare.Immunohistochemically,the tumor cells were positive for Vimentin,INI-1,CD99,NKX2.2,CyclinD1,friend leukaemia virus integration 1,and NKX3.1.Next-generation sequencing revealed the presence of the EWSR1-NFATC2 fusion gene.EWSR1/FUS::NFATC2 rearranged sarcomas are rare and can easily be misdiagnosed.CONCLUSION Clinical imaging,immunohistochemistry,and molecular pathology should be considered to confirm the diagnosis. 展开更多
关键词 EWSR1 NFATC2 SARCOMA FOREARM Case report
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Combining single-cell RNA sequencing and population-based studies reveals hand osteoarthritis-associated chondrocyte subpopulations and pathways
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作者 Hui Li Xiaofeng Jiang +11 位作者 Yongbing Xiao Yuqing Zhang Weiya Zhang Michael Doherty Jacquelyn Nestor Changjun Li Jing Ye Tingting Sha Houchen Lyu Jie Wei chao zeng Guanghua Lei 《Bone Research》 SCIE CAS CSCD 2023年第4期834-846,共13页
Hand osteoarthritis is a common heterogeneous joint disorder with unclear molecular mechanisms and no disease-modifying drugs.In this study,we performed single-cell RNA sequencing analysis to compare the cellular comp... Hand osteoarthritis is a common heterogeneous joint disorder with unclear molecular mechanisms and no disease-modifying drugs.In this study,we performed single-cell RNA sequencing analysis to compare the cellular composition and subpopulationspecific gene expression between cartilage with macroscopically confirmed osteoarthritis(n=5)and cartilage without osteoarthritis(n=5)from the interphalangeal joints of five donors.Of 105142 cells,we identified 13 subpopulations,including a novel subpopulation with inflammation-modulating potential annotated as inflammatory chondrocytes.Fibrocartilage chondrocytes exhibited extensive alteration of gene expression patterns in osteoarthritic cartilage compared with nonosteoarthritic cartilage.Both inflammatory chondrocytes and fibrocartilage chondrocytes showed a trend toward increased numbers in osteoarthritic cartilage.In these two subpopulations from osteoarthritic cartilage,the ferroptosis pathway was enriched,and expression of iron overload-related genes,e.g.,FTH1,was elevated.To verify these findings,we conducted a Mendelian randomization study using UK Biobank and a population-based cross-sectional study using data collected from Xiangya Osteoarthritis Study.Genetic predisposition toward higher expression of FTH1 mRNA significantly increased the risk of hand osteoarthritis(odds ratio=1.07,95%confidence interval:1.02–1.11)among participants(n=332668)in UK Biobank.High levels of serum ferritin(encoded by FTH1),a biomarker of body iron overload,were significantly associated with a high prevalence of hand osteoarthritis among participants(n=1241)of Xiangya Osteoarthritis Study(P-for-trend=0.037).In conclusion,our findings indicate that inflammatory and fibrocartilage chondrocytes are key subpopulations and that ferroptosis may be a key pathway in hand osteoarthritis,providing new insights into the pathophysiology and potential therapeutic targets of hand osteoarthritis. 展开更多
关键词 OSTEOARTHRITIS SUBPOPULATIONS ELEVATED
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Graphene-empowered dynamic metasurfaces and metadevices 被引量:9
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作者 chao zeng Hua Lu +4 位作者 Dong Mao Yueqing Du He Hua Wei Zhao Jianlin Zhao 《Opto-Electronic Advances》 SCIE EI 2022年第4期1-47,共47页
Metasurfaces,with extremely exotic capabilities to manipulate electromagnetic(EM)waves,have derived a plethora of advanced metadevices with intriguing functionalities.Tremendous endeavors have been mainly devoted to t... Metasurfaces,with extremely exotic capabilities to manipulate electromagnetic(EM)waves,have derived a plethora of advanced metadevices with intriguing functionalities.Tremendous endeavors have been mainly devoted to the static metasurfaces and metadevices,where the functionalities cannot be actively tuned in situ post-fabrication.Due to the in-trinsic advantage of active tunability by external stimulus,graphene has been successively demonstrated as a favorable candidate to empower metasurfaces with remarkably dynamic tunability,and their recent advances are propelling the EM wave manipulations to a new height:from static to dynamic.Here,we review the recent progress on dynamic metasur-faces and metadevices enabled by graphene with the focus on electrically-controlled dynamic manipulation of the EM waves covering the mid-infrared,terahertz,and microwave regimes.The fundamentals of graphene,including basic ma-terial properties and plasmons,are first discussed.Then,graphene-empowered dynamic metasurfaces and met-adevices are divided into two categories,i.e.,metasurfaces with building blocks of structured graphene and hybrid metasurfaces integrated with graphene,and their recent advances in dynamic spectrum manipulation,wavefront shap-ing,polarization control,and frequency conversion in near/far fields and global/local ways are elaborated.In the end,we summarize the progress,outline the remaining challenges,and prospect the potential future developments. 展开更多
关键词 metasurface dynamic metasurface GRAPHENE graphene plasmons light field manipulation electromagnetic wave manipulation
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Computational intelligence approach for uncertainty quantification using evidence theory 被引量:4
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作者 Bin Suo Yongsheng Cheng +1 位作者 chao zeng Jun Li 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2013年第2期250-260,共11页
As an alternative or complementary approach to the classical probability theory,the ability of the evidence theory in uncertainty quantification(UQ) analyses is subject of intense research in recent years.Two state-... As an alternative or complementary approach to the classical probability theory,the ability of the evidence theory in uncertainty quantification(UQ) analyses is subject of intense research in recent years.Two state-of-the-art numerical methods,the vertex method and the sampling method,are commonly used to calculate the resulting uncertainty based on the evidence theory.The vertex method is very effective for the monotonous system,but not for the non-monotonous one due to its high computational errors.The sampling method is applicable for both systems.But it always requires a high computational cost in UQ analyses,which makes it inefficient in most complex engineering systems.In this work,a computational intelligence approach is developed to reduce the computational cost and improve the practical utility of the evidence theory in UQ analyses.The method is demonstrated on two challenging problems proposed by Sandia National Laboratory.Simulation results show that the computational efficiency of the proposed method outperforms both the vertex method and the sampling method without decreasing the degree of accuracy.Especially,when the numbers of uncertain parameters and focal elements are large,and the system model is non-monotonic,the computational cost is five times less than that of the sampling method. 展开更多
关键词 uncertainty quantification(UQ) evidence theory hybrid algorithm interval algorithm genetic algorithm(GA).
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Efficient and stable wireless power transfer based on the non-Hermitian physics 被引量:3
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作者 曾超 郭志伟 +8 位作者 祝可嘉 范才富 李果 江俊 李云辉 江海涛 羊亚平 孙勇 陈鸿 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第1期37-44,共8页
As one of the most attractive non-radiative power transfer mechanisms without cables,efficient magnetic resonance wireless power transfer(WPT)in the near field has been extensively developed in recent years,and promot... As one of the most attractive non-radiative power transfer mechanisms without cables,efficient magnetic resonance wireless power transfer(WPT)in the near field has been extensively developed in recent years,and promoted a variety of practical applications,such as mobile phones,medical implant devices and electric vehicles.However,the physical mechanism behind some key limitations of the resonance WPT,such as frequency splitting and size-dependent efficiency,is not very clear under the widely used circuit model.Here,we review the recently developed efficient and stable resonance WPT based on non-Hermitian physics,which starts from a completely different avenue(utilizing loss and gain)to introduce novel functionalities to the resonance WPT.From the perspective of non-Hermitian photonics,the coherent and incoherent effects compete and coexist in the WPT system,and the weak stable of energy transfer mainly comes from the broken phase associated with the phase transition of parity-time symmetry.Based on this basic physical framework,some optimization schemes are proposed,including using nonlinear effect,using bound states in the continuum,or resorting to the system with high-order parity-time symmetry.Moreover,the combination of non-Hermitian physics and topological photonics in multi-coil system also provides a versatile platform for long-range robust WPT with topological protection.Therefore,the non-Hermitian physics can not only exactly predict the main results of current WPT systems,but also provide new ways to solve the difficulties of previous designs. 展开更多
关键词 wireless power transfer non-Hermitian physics topological edge states
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A modified lumped parameter model of distribution transformer winding 被引量:5
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作者 Qingqing Ding Yao Yao +5 位作者 Bingqian Wang Jingwei Fu Wei Zhang chao zeng Xiaoping Li Stanimir Valtchev 《Global Energy Interconnection》 2020年第2期158-165,共8页
The modelling of the distribution transformer winding is the starting point and serves as important basis for the transformer characteristics analysis and the lightning pulse response prediction.A distributed paramete... The modelling of the distribution transformer winding is the starting point and serves as important basis for the transformer characteristics analysis and the lightning pulse response prediction.A distributed parameters model can depict the winding characteristics accurately,but it requires complex calculations.Lumped parameter model requires less calculations,but its applicable frequency range is not wide.This paper studies the amplitude-frequency characteristics of the lightning wave,compares the transformer modelling methods and finally proposes a modified lumped parameter model,based on the above comparison.The proposed model minimizes the errors provoked by the lumped parameter approximation,and the hyperbolic functions of the distributed parameter model.By this modification it becomes possible to accurately describe the winding characteristics and rapidly obtain the node voltage response.The proposed model can provide theoretical and experimental support to lightning protection of the distribution transformer. 展开更多
关键词 Wide band frequency response Distributed parameter model Lumped parameter model Distribution transformer Lightning protection
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Experimental study of multi-timescale crack blunting in hydraulic fracture 被引量:2
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作者 Jing-Nan Dong Guang-Jie Yuan +4 位作者 Xiang-Yang Wang Mian Chen Yan Jin chao zeng Musharraf Zaman 《Petroleum Science》 SCIE CAS CSCD 2021年第1期234-244,共11页
Hydraulic fracture is important in unconventional oil and gas exploration.During the propagation of the hydraulic fracture,the crack tip is blunted due to the development of the process zone in the near-tip area.In th... Hydraulic fracture is important in unconventional oil and gas exploration.During the propagation of the hydraulic fracture,the crack tip is blunted due to the development of the process zone in the near-tip area.In this study,the blunting of the hydraulic fracture in polymethyl methacrylate specimens due to multi-timescale stress concentration is investigated.The ratio of the initiation toughness to the arrest toughness of the blunted hydraulic fracture is measured using both the dynamic and the static methods.Results show that a hydraulic fracture can be blunted with the time span of stress concentration from 1 ms to 600 s.It is also shown that the blunting of hydraulic fracture is a highly localized process.The morphology of the blunted crack depends on the stress distribution in the vicinity of the crack tip. 展开更多
关键词 Hydraulic fracture Crack blunting Crack tip morphology
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Effects of Crocin on Nox2 Expression and ROS Level of Hypoxia/Reoxygenation-induced Injury of Cardiomyocytes 被引量:2
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作者 chao zeng Yongji XING +6 位作者 Lizhi BAO Yuanyuan WANG Weiqing HU Jun WU Xiaohong LIU Nengwu WEN Jiping FAN 《Medicinal Plant》 CAS 2020年第5期71-75,共5页
[Objectives]To explore the protection mechanism of crocin against ischemia-reperfusion injury of myocardial cells.[Methods]Newborn male SD rats were selected,left ventricular cardiomyocytes(CMs)were isolated,and a hyp... [Objectives]To explore the protection mechanism of crocin against ischemia-reperfusion injury of myocardial cells.[Methods]Newborn male SD rats were selected,left ventricular cardiomyocytes(CMs)were isolated,and a hypoxia/reoxygenation model of CMs was established to simulate the process of ischemia/reperfusion injury.The cells were randomly divided into four groups:normal cell group(control group),crocin group),hypoxia/reoxygenation group(H/R group),hypoxia/reoxygenation+crocin group(H/R+crocin group).H/R+crocin group selected the concentration of crocin 1,10,and 100μmol/L,and determined the optimal concentration of crocin by detecting the cell proliferation ability.After the cells were pretreated using the optimal concentration of crocin,the levels of superoxide anion,cell proliferation,apoptosis and Nox2 levels in each group of cells were detected.[Results]Compared with the control group,the proliferation ability of CMs after hypoxia-reoxygenation injury was reduced(P<0.05),while cell apoptosis and intracellular superoxide anion levels were significantly increased(P<0.01);the CMs pretreated with crocin can reduce the level of Nox2(P<0.01),increase the cell proliferation ability of CMs,reduce cell apoptosis,and accordingly reduce the level of superoxide anion in the cell(P<0.05).[Conclusions]Crocin protects CMs from hypoxia/reoxygenation injury through down-regulating the level of Nox2 and reducing oxidative stress injury. 展开更多
关键词 CROCIN Cardiomyocytes(CMs) Hypoxia/reoxygenation injury Oxidative stress
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Experimental Study on the Anti-inflammatory Effect of Ficus pumila L. 被引量:2
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作者 chao zeng Meiyuan LU +2 位作者 Tingting MO Bing WU Qingtong LAN 《Medicinal Plant》 CAS 2020年第4期26-29,共4页
[Objectives]To study the anti-inflammatory effects of extracts from different parts of Ficus pumila L.[Methods]Inflammatory models of xylene-induced ear swelling,glacial acetic acid-induced celiac capillary permeabili... [Objectives]To study the anti-inflammatory effects of extracts from different parts of Ficus pumila L.[Methods]Inflammatory models of xylene-induced ear swelling,glacial acetic acid-induced celiac capillary permeability and carrageenan-induced toe swelling were established to evaluate the effects of extracts from different parts of F.pumila L.on inflammation.The inflammatory model of ear swelling in mice with bilateral adrenalectomy induced by xylene was established to determine whether its anti-inflammatory effect depends on hypothalamus-pituitary-adrenal axis(HPAA)system.[Results]Compared with the blank control group,except that there was no statistical significance in the low dose group(P>0.05),the high and middle dose groups of extracts from different parts of F.pumila L.had significant inhibitory effects on xylene-induced ear swelling in mice.The high,middle and low dose groups of F.pumila L.extract could significantly increase the celiac capillary permeability of mice induced by glacial acetic acid,and significantly inhibit the toe swelling induced by carrageenan.Compared with the blank control group,the high and middle dose groups of extracts from different parts of F.pumila L.could significantly inhibit xylene-induced ear swelling and carrageenan-induced toe swelling in bilateral adrenalectomy mice.[Conclusions]The extracts from different parts of F.pumila L.had anti-inflammatory activity,and its anti-inflammatory effect was independent of hypothalamus-pituitary-adrenal axis(HPAA)system. 展开更多
关键词 Ficus pumila L. Anti-inflammatory effect Preliminary study
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Study on Quality Standards of Laportea bulbifera(Sieb. et Zucc.) Wedd. in Yao’s Folk-medicine 被引量:1
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作者 Wei WEI Huagang LIU +3 位作者 Songji WEI Zhonghua DAI Haicheng WEN chao zeng 《Agricultural Biotechnology》 CAS 2020年第1期110-113,共4页
[Objectives] This study was conducted to establish the quality control standards for Laportea bulbifera(Sieb. et Zucc.) Wedd. [Methods] Microscopic identification and thin layer chromatography were used to identify an... [Objectives] This study was conducted to establish the quality control standards for Laportea bulbifera(Sieb. et Zucc.) Wedd. [Methods] Microscopic identification and thin layer chromatography were used to identify and determine the moisture, total ash and extract contents. [Results] According to the microscopic results, the stem transection is round and has five longitudinal edges at which the cell wall is obviously thickened. Bristles can be observed. A series of collenchyma cells are arranged closely inside the epidermis. There are several rows of parenchyma cells. The vascular bundles are of different sizes;and the ray part is wide, and at the junction of the ray and the cortex, there are often scattered secretory cells. The center is a broad medulla. The powder is brown. There are many starch grains. The bristles are unicelluar, and have warty protrusions and expanded base. The fibers are bundled, and the cells are large. The epidermal cells are in the shape of an elongated spindle, in a mosaic arrangement, and the cell wall is slightly thickened. From the thin layer identification chromatograms of tested L. bulbifera, it can be seen that spots were observed at the same positions as the control medicinal material, and the durability of the method was good. The extract content should not be less than 12.00% by hot extraction with water as solvent, and not be less than 3.00% by cold extraction with ethanol as solvent. The moisture content should not be more than 16.50%. The total ash content should not be more than 14.00%. The acid-insoluble ash content should not be more than 2.50%. [Conclusions] The microscopic identification results are reliable and can be used as the identification basis of L. bulbifera. The thin layer identification method and the test results can provide a basis for quality control of L. bulbifera. 展开更多
关键词 Laportea bulbifera(Sieb.et Zucc.)Wedd. Quality standard Thin layer chromatography
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Study on Quality Evaluation and Standards of the Zhuang Medicine Pandanus tectorius Soland.
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作者 chao zeng Tongyong LUO +3 位作者 Songji WEI Huagang LIU Wei WEI Haicheng WEN 《Agricultural Biotechnology》 CAS 2019年第5期148-151,共4页
[Objectives] This study was conducted to establish the quality control standards for Pandanus tectorius Soland.[Methods] Microscopic identification and thin layer chromatography were used to identify and determine the... [Objectives] This study was conducted to establish the quality control standards for Pandanus tectorius Soland.[Methods] Microscopic identification and thin layer chromatography were used to identify and determine the moisture,total ash and extract contents.[Results] The root transection is near round.The outmost side is velamen.There are nearly 10 columns of collenchyma tissue cells inside.In the cortex,there are a large number of fiber bundles scattered,and there are also large mucous cells scattered.The endodermis is distinct,and the cells are small and closely arranged.The pericycle is distinct and forms a ring.The pericycle fiber bundles are arranged in a radial shape by more than 40 bundles of phloem and xylem alternately.The leaf transection is V-shaped.The collenchyma lies under the epidermis.The spongy tissue has many calcium oxalate square crystal and needle crystals.The mucous cells contain calcium oxalate square crystal and needle crystals.The thin layer identification indicated that in the chromatogram of each test sample,spots of the same colors appeared at the positions corresponding to the chromatogram of the reference medicinal material,and the reproducibility was good.The moisture contents of the 10 batches of samples were all below 8.0%.The total ash was below 8.0%.The acid-insoluble ash was below 2.0%.With 50% ethanol as the solvent,the extract contents were all over 12.5%.[Conclusions] The microscopic identification results are reliable and can be used as the identification basis of P.tectorius.The thin layer identification method and the test results can provide a basis for quality control of P.tectorius. 展开更多
关键词 PANDANUS tectorius Soland. QUALITY standard THIN LAYER CHROMATOGRAPHY Identification
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Fracture Statistics Dominated by Hot-Cutting Defect and Deviation from Weibull Distribution
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作者 chao zeng Chunqing Wang +3 位作者 Yanhong Tian Chunjin Hang Wei Liu Rong An 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2015年第2期41-48,共8页
This paper characterizes the rarely noticeable hot-cutting defect and statistically models the fracture governed by this new type defect. The morphology of the defect on fired ceramic is examined and quantitatively fe... This paper characterizes the rarely noticeable hot-cutting defect and statistically models the fracture governed by this new type defect. The morphology of the defect on fired ceramic is examined and quantitatively featured through comparing the fracture strength governed by intrinsic defect and hot-cutting defect. Weibull distribution is utilized to fit the observed strength data and chi-square goodness-of-fit test is conducted to analyze the deviation. Kernel density estimation is introduced to explore the underlying strength distribution dominated by hot-cutting defect. Based on the shape information from kernel density estimating,gamma and lognormal distribution are compared and the hot-cutting defect governing fracture statistics is finally confirmed by chisquare test. Results show that the newly-defined hot-cutting defect is more dangerous than the intrinsic defect and the priori Weibull distribution fails to describe the fracture statistic governed by the edge defect while the lognormal with a slightly right skewed shape fits it very well. 展开更多
关键词 hot-cutting defect deviation from Weibull Kernel density estimation lognormal distribution
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Determination of Total Anthraquinone and Free Anthraquinone in Different Processed Products of Rhubarb
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作者 Bing WU Jinhua LIU +2 位作者 Meiyuan LU chao zeng Tingting MO 《Medicinal Plant》 CAS 2021年第2期17-20,共4页
[Objectives]The content of total anthraquinone and 5 free anthraquinones in different processed products of rhubarb were determined.[Methods]Using emodin as the reference,the concentration of 1%magnesium acetate metha... [Objectives]The content of total anthraquinone and 5 free anthraquinones in different processed products of rhubarb were determined.[Methods]Using emodin as the reference,the concentration of 1%magnesium acetate methanol solution was used for color development,and the absorbance was measured at 516 nm wavelength;the mobile phase was methanol-0.1%phosphoric acid(76∶24)aqueous solution,the detection wavelength was set at 256 nm,the flow rate was 1.0 mL/min,the column temperature was 30℃,and the sample size was 10μL.[Results]The content of total anthraquinones in rhubarb was determined by UV spectrophotometry.The linear range was 0.98-23.52μg/mL,R2=0.9993,the average recoveries were 100.12%,99.66%and 99.15%,with RSDs of 1.58%,0.94%and 1.41%,respectively.The linear ranges of emodin,emodin,emodin,chrysophanol and emodin methyl ether were 0.0207-0.414(R2=0.9999),0.1721-3.442(R2=0.9996),0.0203-0.406(R2=0.9999),0.148-2.96(R2=0.9998)and 0.164-3.28(R2=0.9993),respectively.[Conclusions]The contents of total anthraquinones and free anthraquinones in different processed products of rhubarb were determined by UV spectrophotometry and HPLC.The method can be used for quality control of rhubarb and its different processed products. 展开更多
关键词 Rheum L. Total anthraquinone Free anthraquinones High-performance liquid chromatography(HPLC) Ultraviolet-visible spectrophotometry(UV-Vis)
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Determination of Polydatin in Rat Serum and Its Changes by UPLC Method
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作者 Haisheng zeng Zhiqiang WANG +3 位作者 Meiyuan LU chao zeng Mengxia YANG Guilin YANG 《Medicinal Plant》 CAS 2021年第2期63-64,69,共3页
[Objectives]To establish a UPLC-UV method for the determination of polydatin in the serum of Wistar rats.[Methods]Acquity UPLC BEH shield RP18 column(1.7μm,2.1 mm×100 mm,Waters Corporation,USA)was used as the an... [Objectives]To establish a UPLC-UV method for the determination of polydatin in the serum of Wistar rats.[Methods]Acquity UPLC BEH shield RP18 column(1.7μm,2.1 mm×100 mm,Waters Corporation,USA)was used as the analytical column,acetonitrile-water(55∶45)was used as the mobile phase,the flow rate was 0.5 mL/min,and the column temperature was 30℃and the detection wavelength was 306 nm.[Results]The linear range of the established serum sample analysis method was 1.0-20.0μg/mL,and the correlation coefficient was r=0.9994;the intraday and interday RSD of Wistar rat serum was less than 3.0%,and the accuracy was higher than 90%.[Conclusions]This method is sensitive,accurate,and rapid.It is suitable for monitoring the concentration of polydatin in serum after intragastric administration,and can also be used for pharmacokinetics and bioavailability studies. 展开更多
关键词 POLYDATIN Drug concentration in serum Content determination Ultra Performance Liquid Chromatography(UPLC)
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Extraction Process and Content Determination of Total Flavonoids in Lonicera japonica
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作者 Yao HUANG Xiumei MA +5 位作者 chao zeng Xiaoling CAI Jie HE Xi FENG Jiangcun WEI Hongxia CHEN 《Medicinal Plant》 CAS 2020年第6期55-58,共4页
[Objectives]To optimize the extraction process of total flavonoids of Lonicerae japonica and establish a method for its extraction and content determination.[Methods]The total flavonoids of L.japonica were extracted b... [Objectives]To optimize the extraction process of total flavonoids of Lonicerae japonica and establish a method for its extraction and content determination.[Methods]The total flavonoids of L.japonica were extracted by reflux extraction method.Through a single factor experiment,the effects of extraction method,extraction solvent concentration,extraction volume and extraction time on the total flavonoids content of medicinal materials were investigated to select the optimal extraction process of the total flavonoids of L.japonica.[Results]The optimal extraction process of the total flavonoids of L.japonica was 70%ethanol,1∶30 of solid-to-liquid ratio,and 1.0 h of reflux extraction time.[Conclusions]This method can effectively determine the content of total flavonoids in L.japonica and is expected to provide a certain scientific basis for the study of the quality standard of L.japonica.This method has high reproducibility.It is stable and feasible in extraction of total flavonoids from L.japonica. 展开更多
关键词 Lonicera japonica Thunb Total flavonoids Extraction process UV-visible spectrophotometry
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Tendencies of alloyed engineering in BiOX-based photocatalysts:a state-of-the-art review
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作者 Yan-Dong Sun chao zeng +3 位作者 Xue Zhang Zi-Qi Zhang Bo Yang Sheng-Qi Guo 《Rare Metals》 SCIE EI CAS CSCD 2024年第4期1488-1512,共25页
Energy-saving and environmentally friendly photocatalysis has emerged as a popular research area in response to issues with energy scarcity and environmental degradation.Due to the unique layer-like structure,BiOX(Cl,... Energy-saving and environmentally friendly photocatalysis has emerged as a popular research area in response to issues with energy scarcity and environmental degradation.Due to the unique layer-like structure,BiOX(Cl,Br,I)is frequently used in photocatalysis.However,inherent flaws in BiOX,such as an inappropriate band gap and low carrier separation efficiency,restrict its capacity for photocatalysis.Owing to the tunable grouping layer,alloying engineering is employed to optimize the intrinsic properties of BiOX and alloyed BiOX becomes a promising photocatalytic material.This review describes the structure of BiOX,where tunable halogen layers provide favorable conditions for the implementation of alloying engineering to improve intrinsic properties.The article compares the effects and mechanisms of alloying engineering on the optimization of the energy band structure and carrier behavior of BiOX,and lists various modification methods used to improve the optimization of the intrinsic properties by alloying engineering,including defect engineering,morphology control as well as the synergy between alloying and other modification methods(bismuth-rich strategies,cation doping,construction of heterojunctions and plasma resonance effects).Subsequently,applications of alloyed BiOX in energy and environmental fields are summarized,including contaminant degradation,antibacterial,CO_(2)reduction,nitrogen fixation and organic synthesis.Finally,we summarize the current challenges and future directions of alloyed BiOX.It is expected that this work will provide guidance and assistance for an in-depth study and understanding of the mechanisms of alloying engineering to optimize intrinsic properties and design alloyed BiOX with higher photocatalytic activity. 展开更多
关键词 Bismuth oxyhalide PHOTOCATALYTIC Alloyed engineering Microstructural regulation Application
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A novel Tb^(3+) and Eu^(3+) co-doped dual-emitting phosphate K_(3)SrBi(P_(2)O_(7))_(2) phosphor for application in FIR thermometers
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作者 Baochen Wang Shifeng Sun +5 位作者 Zeqi Li Zongwang Li Weiwei Lin chao zeng Yan-gai Liu Ruiyu Mi 《Journal of Rare Earths》 SCIE EI CAS CSCD 2024年第3期455-463,I0001,共10页
Rare earth co-doped phosphor for fluorescence intensity ratio(FIR) thermometer has gained increasing attention in recent years. Herein, the novel Tb^(3+)and Eu^(3+)co-doped K_(3)SrBi(P_(2)O_(7))_(2)(KSBP) phosphate ph... Rare earth co-doped phosphor for fluorescence intensity ratio(FIR) thermometer has gained increasing attention in recent years. Herein, the novel Tb^(3+)and Eu^(3+)co-doped K_(3)SrBi(P_(2)O_(7))_(2)(KSBP) phosphate phosphors were reported. The crystal structure of the title phosphor was determined using Rietveld refinement and proved to have a three-dimensional structure. The time-resolved spectroscopy reveals that there is almost no energy transfer between Tb^(3+)and Eu^(3+). More importantly, Tb^(3+)and Eu^(3+)emissions show different thermal quenching behaviors, which claims the potential of this material for application in optical thermometer. The FIR of the typical KSBP:0.02Tb^(3+),0.04Eu^(3+)sample demonstrates a polynomial relationship as a function of temperature and the absolute and relative sensitivity are0.025 K^(-1) and 0.59%/K, respectively. In general, our study reports a novel and potential KSBP:Tb^(3+),Eu^(3+)phosphate phosphor that is promising for use in high-sensitive FIR thermometers. 展开更多
关键词 PHOSPHOR THERMOMETER Fluorescence intensity ratio Thermal stability Rare earths
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机械敏感蛋白PC1调控破骨细胞及骨吸收的作用机制
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作者 黄梅 周静璇 +20 位作者 李潇骁 刘冉 姜洋子 陈开璇 焦玉睿 尹欣 刘玲 孙宇晨 王维山 肖业 苏甜 郭奇 黄燕 杨觅 魏婕 L.Darryl Quarles 肖洲生 曾超 罗湘杭 雷光华 李长俊 《Science Bulletin》 SCIE EI CAS CSCD 2024年第12期1964-1979,共16页
Mechanical loading is required for bone homeostasis,but the underlying mechanism is still unclear.Our previous studies revealed that the mechanical protein polycystin-1(PC1,encoded by Pkd1)is critical for bone formati... Mechanical loading is required for bone homeostasis,but the underlying mechanism is still unclear.Our previous studies revealed that the mechanical protein polycystin-1(PC1,encoded by Pkd1)is critical for bone formation.However,the role of PC1 in bone resorption is unknown.Here,we found that PC1directly regulates osteoclastogenesis and bone resorption.The conditional deletion of Pkd1 in the osteoclast lineage resulted in a reduced number of osteoclasts,decreased bone resorption,and increased bone mass.A cohort study of 32,500 patients further revealed that autosomal dominant polycystic kidney disease,which is mainly caused by loss-of-function mutation of the PKD1 gene,is associated with a lower risk of hip fracture than those with other chronic kidney diseases.Moreover,mice with osteoclastspecific knockout of Pkd1 showed complete resistance to unloading-induced bone loss.A mechanistic study revealed that PC1 facilitated TAZ nuclear translocation via the C-terminal tail-TAZ complex and that conditional deletion of Taz in the osteoclast lineage resulted in reduced osteoclastogenesis and increased bone mass.Pharmacological regulation of the PC1-TAZ axis alleviated unloading-and estrogen deficiency-induced bone loss.Thus,the PC1-TAZ axis may be a potential therapeutic target for osteoclast-related osteoporosis. 展开更多
关键词 Polycystin1 OSTEOCLASTOGENESIS Bone resorption Mechanical stress
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