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Thin paints for durable and scalable radiative cooling
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作者 Shanquan Liu fei zhang +3 位作者 Xingyu Chen Hongjie Yan Wei Chen Meijie Chen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第3期176-182,I0006,共8页
Passive daytime radiative cooling(PDRC) is environment-friendly without energy input by enhancing the coating's solar reflectance(R_(solar)) and thermal emittance(ε_(LWIR)) in the atmosphere's long-wave infra... Passive daytime radiative cooling(PDRC) is environment-friendly without energy input by enhancing the coating's solar reflectance(R_(solar)) and thermal emittance(ε_(LWIR)) in the atmosphere's long-wave infrared transmission window.However,high R_(solar) is usually achieved by increasing the coating's thickness,which not only increases materials' cost but also impairs heat transfer.Additionally,the desired high R_(solar) is vulnerable to dust pollution in the outdoors.In this work,a thin paint was designed by mixing hBN plates,PFOTS,and IPA. R_(solar)=0.963 and ε_(LWIR)=0.927 was achieved at a thickness of 150 μm due to the high backscattering ability of scatters.A high through-plane thermal conductivity(~1.82 W m^(-1) K^(-1)) also can be obtained.In addition,the porous structure coupled with the binder PFOTS resulted in a contact angle of 154°,demonstrating excellent durability under dust contamination.Outdoor experiments showed that the thin paint can obtain a 2.3℃ lower temperature for sub-ambient cooling than the reference PDRC coating in the daytime.Furtherly,the above-ambient heat dissipation performance can be enhanced by spraying the thin paint on a 3D heat sink,which was 15.7℃ lower than the reference 1D structure,demonstrating excellent performance for durable and scalable PDRC applications. 展开更多
关键词 Radiative cooling Heat dissipation Solar reflectance Thermal emittance Contact angle
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The application of the strip-shaped cymba conchae orthosis in the nonsurgical correction of complex auricular deformity
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作者 Huijuan Xu Shaoguang Ding +6 位作者 fei zhang Zhifeng zhang Xiangyu Chen Mingyang Li Haitao Yang Fugen Han Hongjian Liu 《Journal of Otology》 CAS CSCD 2024年第1期24-29,共6页
Objective: This study aims to evaluate the efficacy and safety of using a strip-shaped cymba conchae orthosis for the nonsurgical correction of complex auricular deformities. Methods: Clinical data were collected from... Objective: This study aims to evaluate the efficacy and safety of using a strip-shaped cymba conchae orthosis for the nonsurgical correction of complex auricular deformities. Methods: Clinical data were collected from 2020 to 2021 for 6 patients who underwent correction using a stripshaped cymba conchae orthosis. The indications, corrective effects, and complications associated with use of the orthosis were analyzed. Results: There were four indications for treatment: cryptotia with helix adhesion;cryptotia with grade I microtia;cryptotia with excessive helix thickness;and auricular deformity beyond the treatment time window(≥6 months). Excellent corrective effects were observed in all 6 patients. Complications occurred in one patient, who recovered after symptomatic treatment. Conclusion: The use of a strip-shaped cymba conchae orthosis alone or combined with a U-shaped helix orthosis presents a feasible approach for correcting complex auricular deformities or deformities beyond the treatment time window in pediatric patients. 展开更多
关键词 Cymba conchae Auricular deformity Cryptotia Nonsurgical correction ORTHOSIS
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Self-assembly of perovskite nanocrystals:From driving forces to applications
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作者 Yi Li fei zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第1期561-578,I0013,共19页
Self-assembly of metal halide perovskite nanocrystals(NCs)into superlattices can exhibit unique collective properties,which have significant application values in the display,detector,and solar cell field.This review ... Self-assembly of metal halide perovskite nanocrystals(NCs)into superlattices can exhibit unique collective properties,which have significant application values in the display,detector,and solar cell field.This review discusses the driving forces behind the self-assembly process of perovskite NCs,and the commonly used self-assembly methods and different self-assembly structures are detailed.Subsequently,we summarize the collective optoelectronic properties and application areas of perovskite superlattice structures.Finally,we conclude with an outlook on the potential issues and future challenges in developing perovskite NCs. 展开更多
关键词 SELF-ASSEMBLY Metal halide perovskite NANOCRYSTALS Driving forces
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Elliptical encirclement control capable of reinforcing performances for UAVs around a dynamic target
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作者 fei zhang Xingling Shao +1 位作者 Yi Xia Wendong zhang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第2期104-119,共16页
Most researches associated with target encircling control are focused on moving along a circular orbit under an ideal environment free from external disturbances.However,elliptical encirclement with a time-varying obs... Most researches associated with target encircling control are focused on moving along a circular orbit under an ideal environment free from external disturbances.However,elliptical encirclement with a time-varying observation radius,may permit a more flexible and high-efficacy enclosing solution,whilst the non-orthogonal property between axial and tangential speed components,non-ignorable environmental perturbations,and strict assignment requirements empower elliptical encircling control to be more challenging,and the relevant investigations are still open.Following this line,an appointed-time elliptical encircling control rule capable of reinforcing circumnavigation performances is developed to enable Unmanned Aerial Vehicles(UAVs)to move along a specified elliptical path within a predetermined reaching time.The remarkable merits of the designed strategy are that the relative distance controlling error can be guaranteed to evolve within specified regions with a designer-specified convergence behavior.Meanwhile,wind perturbations can be online counteracted based on an unknown system dynamics estimator(USDE)with only one regulating parameter and high computational efficiency.Lyapunov tool demonstrates that all involved error variables are ultimately limited,and simulations are implemented to confirm the usability of the suggested control algorithm. 展开更多
关键词 Elliptical encirclement Reinforced performances Wind perturbations UAVS
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Degradable magnesium alloy suture promotes fibrocartilaginous interface regeneration in a rat rotator cuff transosseous repair model
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作者 Baoxiang zhang Wen zhang +5 位作者 fei zhang Chao Ning Mingyang An Ke Yang Lili Tan Qiang zhang 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第1期384-393,共10页
Despite transosseous rotator cuff tear repair using sutures is widely accepted for tendon-bone fixation,the fibrocartilaginous enthesis regeneration is still hardly achieved with the traditional sutures.In the present... Despite transosseous rotator cuff tear repair using sutures is widely accepted for tendon-bone fixation,the fibrocartilaginous enthesis regeneration is still hardly achieved with the traditional sutures.In the present work,degradable magnesium(Mg)alloy wire was applied to suture supraspinatus tendon in a rat acute rotator cuff tear model with Vicryl Plus 4±0 absorbable suture as control.The shoulder joint humerus-supraspinatus tendon complex specimens were retrieved at 4,8,and 12 weeks after operation.The Mg alloy suture groups showed better biomechanical properties in terms of ultimate load to failure.Gross observation showed that hyperplastic response of the scar tissue at the tendon-bone interface is progressively alleviated over time in the both Mg alloy suture and Vicryl suture groups.In the histological analysis,for Mg alloy suture groups,chondrocytes appear to proliferate at 4 weeks postoperatively,and the tendon-bone interface showed an orderly structural transition zone at 8 weeks postoperatively.The collagenous fiber tended to be aligned and the tendon-bone interlocking structures apparently formed,where transitional structure from unmineralized fibrocartilage to mineralized fibrocartilage was closer to the native fibrocartilaginous enthesis.In vivo degradation of the magnesium alloy wire was completed within 12 weeks.The results indicated that Mg alloy wire was promising as degradable suture with the potential to promotes fibrocartilaginous interface regeneration in rotator cuff repair. 展开更多
关键词 Rotator cuff repair Mg alloy wire Tendon-bone healing Fibrocartilaginous interface
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基于UPLC-Q-TOF/MS及CORT诱导的低分化PC12抑郁细胞模型的柴胡抗抑郁活性成分研究 被引量:1
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作者 于静波 韩越 +5 位作者 周梓洋 牟晴蕊 陈静梅 欧阳煜钦 费璋 王宇红 《世界科学技术-中医药现代化》 CSCD 北大核心 2023年第6期2012-2024,共13页
目的分析鉴定柴胡水提物中的化学成分,探究柴胡抗抑郁活性成分。方法利用超高效液相色谱串联四极杆飞行时间质谱(UPLC-Q-TOF/MS)分析鉴定柴胡水提物中的化学成分。采用皮质酮(CORT)诱导低分化PC12抑郁细胞模型,给予柴胡单体成分预处理P... 目的分析鉴定柴胡水提物中的化学成分,探究柴胡抗抑郁活性成分。方法利用超高效液相色谱串联四极杆飞行时间质谱(UPLC-Q-TOF/MS)分析鉴定柴胡水提物中的化学成分。采用皮质酮(CORT)诱导低分化PC12抑郁细胞模型,给予柴胡单体成分预处理PC12细胞24 h,利用CCK-8试剂盒检测细胞活力;利用乳酸脱氢酶(LDH)试剂盒检测细胞LDH释放率。结果共鉴定出53个化学成分,主要为Ⅰ型、Ⅱ型及Ⅲ型柴胡皂苷类成分。其中,柴胡皂苷A、柴胡皂苷B2、柴胡皂苷C、柴胡皂苷E、柴胡皂苷F和6″-O-乙酰基柴胡皂苷A对柴胡代谢轮廓的贡献度最大,并可增强CORT诱导PC12细胞活力(P<0.05、P<0.01);柴胡皂苷A、柴胡皂苷B2、柴胡皂苷C、柴胡皂苷E、柴胡皂苷F可降低CORT诱导PC12细胞LDH释放率(P<0.05、P<0.01)。结论柴胡皂苷A、柴胡皂苷B2、柴胡皂苷C、柴胡皂苷E、柴胡皂苷F可能为柴胡抗抑郁的主要活性成分,为柴胡质量控制及药效物质基础研究提供依据。 展开更多
关键词 柴胡 抑郁症 液质联用 PC12细胞 活性成分
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Mixed Cations Enabled Combined Bulk and Interfacial Passivation for Efficient and Stable Perovskite Solar Cells 被引量:1
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作者 Pengfei Wu Shirong Wang +4 位作者 Jin Hyuck Heo Hongli Liu Xihan Chen Xianggao Li fei zhang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第8期116-127,共12页
Here,we report a mixed GAI and MAI(MGM)treatment method by forming a 2D alternating-cation-interlayer(ACI)phase(n=2)perovskite layer on the 3D perovskite,modulating the bulk and interfacial defects in the perovskite f... Here,we report a mixed GAI and MAI(MGM)treatment method by forming a 2D alternating-cation-interlayer(ACI)phase(n=2)perovskite layer on the 3D perovskite,modulating the bulk and interfacial defects in the perovskite films simultaneously,leading to the suppressed nonradiative recombination,longer lifetime,higher mobility,and reduced trap density.Consequently,the devices’performance is enhanced to 24.5%and 18.7%for 0.12 and 64 cm^(2),respectively.In addition,the MGM treatment can be applied to a wide range of perovskite compositions,including MA-,FA-,MAFA-,and CsFAMA-based lead halide perovskites,making it a general method for preparing efficient perovskite solar cells.Without encapsulation,the treated devices show improved stabilities. 展开更多
关键词 Alternating-cation-interlayer Bulk defects Interfacial passivation Perovskite solar cells
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Physics-data-driven intelligent optimization for large-aperture metalenses 被引量:1
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作者 Yingli Ha Yu Luo +9 位作者 Mingbo Pu fei zhang Qiong He Jinjin Jin Mingfeng Xu Yinghui Guo Xiaogang Li Xiong Li Xiaoliang Ma Xiangang Luo 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2023年第11期5-15,共11页
Metalenses have gained significant attention and have been widely utilized in optical systems for focusing and imaging,owing to their lightweight,high-integration,and exceptional-flexibility capabilities.Traditional d... Metalenses have gained significant attention and have been widely utilized in optical systems for focusing and imaging,owing to their lightweight,high-integration,and exceptional-flexibility capabilities.Traditional design methods neglect the coupling effect between adjacent meta-atoms,thus harming the practical performance of meta-devices.The existing physical/data-driven optimization algorithms can solve the above problems,but bring significant time costs or require a large number of data-sets.Here,we propose a physics-data-driven method employing an“intelligent optimizer”that enables us to adaptively modify the sizes of the meta-atom according to the sizes of its surrounding ones.The implementation of such a scheme effectively mitigates the undesired impact of local lattice coupling,and the proposed network model works well on thousands of data-sets with a validation loss of 3×10^(−3).Based on the“intelligent optimizer”,a 1-cm-diameter metalens is designed within 3 hours,and the experimental results show that the 1-mm-diameter metalens has a relative focusing efficiency of 93.4%(compared to the ideal focusing efficiency)and a Strehl ratio of 0.94.Compared to previous inverse design method,our method significantly boosts designing efficiency with five orders of magnitude reduction in time.More generally,it may set a new paradigm for devising large-aperture meta-devices. 展开更多
关键词 intelligence method physics-data-driven method inverse design large-aperture metalenses
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Optimization of enrichment and pretreatment of low-activity radium isotopes in the open ocean
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作者 Guiyuan Dai Guizhi Wang +2 位作者 Qing Li Weizhen Jiang fei zhang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第8期171-177,共7页
In the open ocean,radium isotopes are useful tracers of residence time and water-mass mixing.However,limited by the measurement resolution of commonly used gamma counters,the low activity of radium in the open ocean m... In the open ocean,radium isotopes are useful tracers of residence time and water-mass mixing.However,limited by the measurement resolution of commonly used gamma counters,the low activity of radium in the open ocean makes it necessary to enrich radium from large volumes of seawater and pretreat radium-enriched carriers prior to measurements.The commonly applied method of radium enrichment and pretreatment,however,has limitations of uneven coating of MnO_(2)on cartridges,relatively expensive cartridges,time-consuming issues during cartridge-ashing,ash loss during transfer,and changes of gamma counters efficiency caused by different ash weights.To address these issues,in this study we optimized the enrichment and pretreatment of low-activity radium prior to measurements.Firstly,we replaced commonly used acrylic cartridges with cheaper polypropylene cartridges,which took 6 h to be ashed,42 h shorter than for acrylic cartridges.Secondly,MnO_(2)-coated cartridges were prepared with a circulating hot acidic KMnO_(4)solution to ensure homogeneous coating.The radium extraction efficiency of this MnO_(2)-coated cartridge was 20%-61%higher than that prepared by directly immersing cartridges in the solution.The radium delayed coincidence counter efficiency for MnO_(2)-coated cartridge was stable with a moisture content of 0.05-1.Lastly,after ashing cartridges,instead of directly transferring the ash to a measurement vial,a mixture of hydroxylamine hydrochloride and hydrochloric acid was used to completely leach the ash for long-lived radium,followed by coprecipitation by BaSO_(4),to avoid potential loss of ash during transfer and variations in measurement geometry due to different ash weights.And the recovery of long-lived radium pretreatment was 94%-102%,which improved by 11%compared with the common method.In addition,the radium extraction efficiency of the MnO_(2)-coated cartridge varied from 3%to 4%within the in situ pump working flow rate of 4-7 L/min,which fell within the measurement errors. 展开更多
关键词 radium isotopes MnO_(2)-coated cartridge enrichment of Ra pretreatment of MnO_(2)-coated cartridges RaDeCC efficiency extraction efficiency
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An efficient transient gene expression system for protein subcellular localization assay and genome editing in citrus protoplasts
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作者 Wenhui Yang Jiaqin Ren +6 位作者 Wanrong Liu Dan Liu Kaidong Xie fei zhang Pengwei Wang Wenwu Guo Xiaomeng Wu 《Horticultural Plant Journal》 SCIE CAS CSCD 2023年第3期425-436,共12页
Protoplast has been widely used in biotechnologies to circumvent the breeding obstacles in citrus, including long juvenility, polyembryony, and male/female sterility. The protoplast-based transient gene expression sys... Protoplast has been widely used in biotechnologies to circumvent the breeding obstacles in citrus, including long juvenility, polyembryony, and male/female sterility. The protoplast-based transient gene expression system is a powerful tool for gene functional characterization and CRISPR/Cas9 genome editing in higher plants, but it has not been widely used in citrus. In this study, the polyethylene glycol(PEG)-mediated method was optimized for citrus callus protoplast transfection, with an improved transfection efficiency of 68.4%. Consequently, the efficiency of protein subcellular localization assay was increased to 65.8%, through transient expression of the target gene in protoplasts that stably express the fluorescent organelle marker protein. The gene editing frequencies in citrus callus protoplasts reached 14.2% after transient expression of CRISPR/Cas9 constructs. We demonstrated that the intronic polycistronic tRNAgRNA(inPTG) genome editing construct was functional in both the protoplast transient expression system and epicotyl stable transformation system in citrus. With this optimized protoplast transient expression system, we improved the efficiency of protein subcellular localization assay and developed the genome editing system in callus protoplasts, which provides an approach for prompt test of CRISPR vectors. 展开更多
关键词 CITRUS Callus protoplast Transient transfection Subcellular localization Genome editing
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FAR591 promotes the pathogenesis and progression of SONFH by regulating Fos expression to mediate the apoptosis of bone microvascular endothelial cells
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作者 fei zhang Lei Wei +10 位作者 Lei Wang Tao Wang Zhihong Xie Hong Luo Fanchao Li Jian zhang Wentao Dong Gang Liu Qinglin Kang Xuesong Zhu Wuxun Peng 《Bone Research》 SCIE CAS CSCD 2023年第2期398-415,共18页
The specific pathogenesis of steroid-induced osteonecrosis of the femoral head(SONFH)is still not fully understood,and there is currently no effective early cure.Understanding the role and mechanism of long noncoding ... The specific pathogenesis of steroid-induced osteonecrosis of the femoral head(SONFH)is still not fully understood,and there is currently no effective early cure.Understanding the role and mechanism of long noncoding RNAs(lnc RNAs)in the pathogenesis of SONFH will help reveal the pathogenesis of SONFH and provide new targets for its early prevention and treatment.In this study,we first confirmed that glucocorticoid(GC)-induced apoptosis of bone microvascular endothelial cells(BMECs)is a pre-event in the pathogenesis and progression of SONFH.Then,we identified a new lnc RNA in BMECs via lnc RNA/m RNA microarray,termed Fosassociated linc RNA ENSRNOT00000088059.1(FAR591).FAR591 is highly expressed during GC-induced BMEC apoptosis and femoral head necrosis.Knockout of FAR591 effectively blocked the GC-induced apoptosis of BMECs,which then alleviated the damage of GCs to the femoral head microcirculation and inhibited the pathogenesis and progression of SONFH.In contrast,overexpression of FAR591 significantly promoted the GC-induced apoptosis of BMECs,which then aggravated the damage of GCs to the femoral head microcirculation and promoted the pathogenesis and progression of SONFH.Mechanistically,GCs activate the glucocorticoid receptor,which translocates to the nucleus and directly acts on the FAR591 gene promoter to induce FAR591 gene overexpression.Subsequently,FAR591 binds to the Fos gene promoter(–245–51)to form a stable RNA:DNA triplet structure and then recruits TATA-box binding protein associated factor 15 and RNA polymerase II to promote Fos expression through transcriptional activation.Fos activates the mitochondrial apoptotic pathway by regulating the expression of Bcl-2 interacting mediator of cell death(Bim)and P53 upregulated modulator of apoptosis(Puma)to mediate GC-induced apoptosis of BMECs,which leads to femoral head microcirculation dysfunction and femoral head necrosis.In conclusion,these results confirm the mechanistic link between lnc RNAs and the pathogenesis of SONFH,which helps reveal the pathogenesis of SONFH and provides a new target for the early prevention and treatment of SONFH. 展开更多
关键词 PATHOGENESIS prevention inhibited
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双中心多孔聚合物作为多相催化剂实现CO_(2)在温和条件下高效转化 被引量:2
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作者 戴志锋 唐永铨 +7 位作者 张飞 熊玉兵 王赛 孙琦 王亮 孟祥举 赵雷洪 肖丰收 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2021年第4期618-626,共9页
由于对化石燃料的高度依赖和二氧化碳(CO_(2))的过度排放,大气中CO_(2)浓度从280 ppm上升到400 ppm左右,导致全球变暖和其他气候问题.在这种情况下,如何有效降低空气中的CO_(2)浓度成为近年来最迫切的研究领域之一.另一方面,作为一种无... 由于对化石燃料的高度依赖和二氧化碳(CO_(2))的过度排放,大气中CO_(2)浓度从280 ppm上升到400 ppm左右,导致全球变暖和其他气候问题.在这种情况下,如何有效降低空气中的CO_(2)浓度成为近年来最迫切的研究领域之一.另一方面,作为一种无毒、廉价且丰富的C1资源,CO_(2)也可以转化为各种高附加值的工业产品,如甲酸、一氧化碳、甲烷、甲醇以及碳酸酯等.其中CO_(2)与环氧化物转化生成环碳酸酯的环加成反应具有良好原子经济性,在近年来引起了人们的广泛关注.尽管已有多种多相和均相催化剂应用于该反应,但已有的催化剂特别是多相催化剂往往具有反应条件苛刻、催化剂易损失以及需要可溶性的共催化剂等缺点,从而限制了它们的进一步实际应用.因此,发展多相催化剂实现在温和和无共催化剂条件下的CO_(2)环加成转化仍是一个挑战.本文通过自由基共聚的方法,以乙烯基功能化的金属卟啉和季膦盐作为单体制备了一种新型多孔有机聚合物(POP-PBnCl-TPPMg-x).考虑到金属卟啉和季膦盐常作为CO_(2)环加成反应中的Lewis酸和Lewis碱活性中心,我们通过自由基共聚实现了这两种活性中心在分子水平上的结合与协同.所得的催化剂的组成和结构通过固体核磁、X射线光电子能谱、氮气吸附、扫描电子显微镜、透射式电子显微镜等手段进行了表征.值得指出的是,所得多相催化剂具有良好的CO_(2)吸附与富集效应,十分有利于CO_(2)的催化转化.我们以温和(40℃和1 atm CO_(2))并没有任何无可溶性共催化剂存在条件下,进行CO_(2)与环氧化物的环加成作为探针反应,测试了不同催化剂的催化活性.以催化剂POP-PBnCl-TPPMg-12为例,其催化活性远超过单组分的POP-PBnCl和POP-TPPMg多相催化剂,也超过了二者机械混合的POP-PBnCl+POP-TPPMg-12催化剂,接近均相催化剂PBnCl+TPPMg-12的水平.这表明通过共聚合方法所得到的催化剂可以实现Lewis酸和Lewis碱两种活性中心的分子水平的结合.本文进一步研究了多相催化剂POP-PBnCl-TPPMg-12和均相催化剂PBnCl+TPPMg-12在低浓度CO_(2)(15%N2 v/v,工业废气中CO_(2)的浓度)条件下的催化活性,发现在该条件下多相催化剂表现出比均相催化剂更为优异的催化转化性能,且展现出良好的稳定性和循环使用性能,在循环使用5次后仍无明显的活性损失.该催化剂所具有的多相特点和优良的催化性能,因而有望成为实现工业CO_(2)脱除并转化成高附加值产品的潜在高效催化剂. 展开更多
关键词 共聚 多孔有机聚合物 双活性中心 CO_(2)固定 多相催化
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Autophagy inhibition enhances apigenin-induced apoptosis in human breast cancer cells 被引量:12
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作者 Xuchen Cao Bowen Liu +8 位作者 Wenfeng Cao Weiran zhang fei zhang Hongmeng Zhao Ran Meng Lin zhang Ruifang Niu Xishan Hao Bin zhang 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2013年第2期212-222,共11页
Apigenin (4',5,7-trihydroxyflavone) is a member of the flavone subclass of flavonoids present in fruits and vegetables. The involvement of autophagy in the apigenin-induced apoptotic death of human breast cancer c... Apigenin (4',5,7-trihydroxyflavone) is a member of the flavone subclass of flavonoids present in fruits and vegetables. The involvement of autophagy in the apigenin-induced apoptotic death of human breast cancer cells was investigated. Cell proliferation and viability were assessed by 3-(4,5-dimethylthiazol- 2-yl)-2,5-diphenyltetrazolium bromide (MTT) and clonogenic assays. Flow cytometry, fluorescent staining and Western blot analysis were employed to detect apoptosis and autophagy, and the role of autophagy was assessed using autophagy inhibitors. Apigenin dose- and time-dependently repressed the proliferation and clonogenic survival of the human breast cancer T47D and MDA-MB-231 cell lines. The death of T47D and MDA-MB-231 cells was due to apoptosis associated with increased levels of Caspase3, PARP cleavage and Bax/Bcl-2 ratios. The results from flow cytometry and fluorescent staining also verified the occurrence of apoptosis. In addition, the apigenin-treated cells exhibited autophagy, as characterized by the appearance of autophagosomes under fluorescence microscopy and the accumulation of acidic vesicular organelles (AVOs) by flow cytometry. Furthermore, the results of the Western blot analysis revealed that the level of LC3-II, the processed form of LC3-I, was increased. Treatment with the autophagy inhibitor, 3-methyladenine (3-MA), significantly enhanced the apoptosis induced by apigenin, which was accompanied by an increase in the level of PARP cleavage. Similar results were also confirmed by flow cytometry and fluorescence microscopy. These results indicate that apigenin has apoptosis-and autophagy-inducing effects in breast cancer cells. Autophagy plays a cyto-protective role in apigenin-induced apoptosis, and the combination of apigenin and an autophagy inhibitor may be a promising strategy for breast cancer control. 展开更多
关键词 乳腺癌细胞 自噬作用 细胞凋亡 芹菜素 诱导 WESTERN印迹 黄酮类化合物 流式细胞仪
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Vegetation fractional coverage change in a typical oasis region in Tarim River Watershed based on remote sensing 被引量:12
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作者 fei zhang Tashpolat TIYIP +4 位作者 JianLi DING Mamat SAWUT Verner Carl JOHNSON NigaraTASHPOLAT DongWei GUI 《Journal of Arid Land》 SCIE CSCD 2013年第1期89-101,共13页
Vegetation fractional coverage(VFC) is an important index to describe and evaluate the ecological system.The vegetation index is widely used to monitor vegetation coverage in the field of remote sensing(RS).In this pa... Vegetation fractional coverage(VFC) is an important index to describe and evaluate the ecological system.The vegetation index is widely used to monitor vegetation coverage in the field of remote sensing(RS).In this paper,the author conducted a case study of the delta oasis of Weigan and Kuqa rivers,which is a typical saline area in the Tarim River Watershed.The current study was based on the TM/ETM+ images of 1989,2001,and 2006,and supported by Geographic Information System(GIS) spatial analysis,vegetation index,and dimidiate pixel model.In addition,VBSI(vegetation,bare soil and shadow indices) suitable for TM/ETM+ images,constructed with FCD(forest canopy density) model principle and put forward by ITTO(International Tropical Timber Organization),was used,and it was applied to estimate the VFC.The estimation accuracy was later proven to be up to 83.52%.Further,the study analyzed and appraised the changes in vegetation patterns and revealed a pattern of spatial change in the vegetation coverage of the study area by producing the map of VFC levels in the delta oasis.Forest,grassland,and farmland were the three main land-use types with high and extremely-high coverage,and they played an important role in maintaining the vegetation.The forest area determined the changes of the coverage area,whereas the other two land types affected the directions of change.Therefore,planting trees,protecting grasslands,reclaiming farmlands,and controlling unused lands should be included in a long-term program because of their importance in keeping regional vegetation coverage.Finally,the dynamic variation of VFC in the study area was evaluated according to the quantity and spatial distribution rendered by plant cover digital images to deeply analyze the reason behind the variation. 展开更多
关键词 植被覆盖度 塔里木河流域 荒漠绿洲区 遥感 ETM图像 国际热带木材组织 像元二分模型 土地利用类型
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SHP2 promotes proliferation of breast cancer cells through regulating Cyclin D1 stabilityviathe PI3K/AKT/GSK3β signaling pathway 被引量:11
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作者 Yue Yuan Yanling Fan +8 位作者 Zicong Gao Xuan Sun He zhang Zhiyong Wang Yanfen Cui Weijie Song Zhaosong Wang fei zhang Ruifang Niu 《Cancer Biology & Medicine》 SCIE CAS CSCD 2020年第3期707-725,共19页
Objective:The tyrosine phosphatase SHP2 has a dual role in cancer initiation and progression in a tissue type-dependent manner.Several studies have linked SHP2 to the aggressive behavior of breast cancer cells and poo... Objective:The tyrosine phosphatase SHP2 has a dual role in cancer initiation and progression in a tissue type-dependent manner.Several studies have linked SHP2 to the aggressive behavior of breast cancer cells and poorer outcomes in people with cancer.Nevertheless,the mechanistic details of how SHP2 promotes breast cancer progression remain largely undefined.Methods:The relationship between SHP2 expression and the prognosis of patients with breast cancer was investigated by using the TCGA and GEO databases.The expression of SHP2 in breast cancer tissues was analyzed by immunohistochemistry.CRISPR/Cas9 technology was used to generate SHP2-knockout breast cancer cells.Cell-counting kit-8,colony formation,cell cycle,and EdU incorporation assays,as well as a tumor xenograft model were used to examine the function of SHP2 in breast cancer proliferation.Quantitative RT-PCR,western blotting,immunofluorescence staining,and ubiquitination assays were used to explore the molecular mechanism through which SHP2 regulates breast cancer proliferation.Results:High SHP2 expression is correlated with poor prognosis in patients with breast cancer.SHP2 is required for the proliferation of breast cancer cellsin vitro and tumor growthin vivo through regulation of Cyclin D1 abundance,thereby accelerating cell cycle progression.Notably,SHP2 modulates the ubiquitin–proteasome-dependent degradation of Cyclin D1viathe PI3K/AKT/GSK3βsignaling pathway.SHP2 knockout attenuates the activation of PI3K/AKT signaling and causes the dephosphorylation and resultant activation of GSK3β.GSK3βthen mediates phosphorylation of Cyclin D1 at threonine 286,thereby promoting the translocation of Cyclin D1 from the nucleus to the cytoplasm and facilitating Cyclin D1 degradation through the ubiquitin–proteasome system.Conclusions:Our study uncovered the mechanism through which SHP2 regulates breast cancer proliferation.SHP2 may therefore potentially serve as a therapeutic target for breast cancer. 展开更多
关键词 SHP2 breast cancer PROLIFERATION Cyclin D1 GSK3Β PI3K/AKT
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TGF-β与细胞内信号通路的交互作用在肿瘤研究中的进展 被引量:10
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作者 冀为 赵元元 +1 位作者 张飞 牛瑞芳 《中国肿瘤临床》 CAS CSCD 北大核心 2018年第15期800-803,共4页
转化生长因子-β(transforming growth factor-β,TGF-β)信号通路在肿瘤发生发展过程中发挥双向调节作用。TGF-β能够抑制上皮细胞的生长、增殖并诱导其凋亡,发挥抑制肿瘤的作用,因此上皮细胞失去对TGF-β抑制增殖的反应是肿瘤发生过... 转化生长因子-β(transforming growth factor-β,TGF-β)信号通路在肿瘤发生发展过程中发挥双向调节作用。TGF-β能够抑制上皮细胞的生长、增殖并诱导其凋亡,发挥抑制肿瘤的作用,因此上皮细胞失去对TGF-β抑制增殖的反应是肿瘤发生过程中的标志性事件。随着肿瘤进展,TGF-β能够促进肿瘤细胞侵袭、转移、耐药以及维持肿瘤干细胞潜能。目前,TGF-β的上述作用转变与其细胞内多条信号通路的交互作用有关,这种交互作用既能减弱或解除TGF-β的增殖抑制和促凋亡作用,又能增强其促进肿瘤进展和恶化的功能。本文主要针对TGF-β在肿瘤进展中与多条细胞内信号通路交互联系的分子机制,以及交互作用对肿瘤发生发展的影响进行综述。 展开更多
关键词 转化生长因子Β 上皮间质转化 信号通路 表皮生长因子受体 磷脂酰肌醇-3-激酶
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Current achievements and future prospects in the genetic breeding of chrysanthemum:a review 被引量:13
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作者 Jiangshuo Su Jiafu Jiang +4 位作者 fei zhang Ye Liu Lian Ding Sumei Chen Fadi Chen 《Horticulture Research》 SCIE 2019年第1期378-396,共19页
Chrysanthemum(Chrysanthemum morifolium Ramat.)is a leading flower with applied value worldwide.Developing new chrysanthemum cultivars with novel characteristics such as new flower colors and shapes,plant architectures... Chrysanthemum(Chrysanthemum morifolium Ramat.)is a leading flower with applied value worldwide.Developing new chrysanthemum cultivars with novel characteristics such as new flower colors and shapes,plant architectures,flowering times,postharvest quality,and biotic and abiotic stress tolerance in a time-and cost-efficient manner is the ultimate goal for breeders.Various breeding strategies have been employed to improve the aforementioned traits,ranging from conventional techniques,including crossbreeding and mutation breeding,to a series of molecular breeding methods,including transgenic technology,genome editing,and marker-assisted selection(MAS).In addition,the recent extensive advances in high-throughput technologies,especially genomics,transcriptomics,proteomics,metabolomics,and microbiomics,which are collectively referred to as omics platforms,have led to the collection of substantial amounts of data.Integration of these omics data with phenotypic information will enable the identification of genes/pathways responsible for important traits.Several attempts have been made to use emerging molecular and omics methods with the aim of accelerating the breeding of chrysanthemum.However,applying the findings of such studies to practical chrysanthemum breeding remains a considerable challenge,primarily due to the high heterozygosity and polyploidy of the species.This review summarizes the recent achievements in conventional and modern molecular breeding methods and emerging omics technologies and discusses their future applications for improving the agronomic and horticultural characteristics of chrysanthemum. 展开更多
关键词 BREEDING CHRYSANTHEMUM CULTIVAR
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Brain metastasis in children with stage 4 neuroblastoma after multidisciplinary treatment 被引量:4
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作者 Jia Zhu Juan Wang +7 位作者 Zi-Jun Zhen Su-Ying Lu fei zhang fei-fei Sun Peng-fei Li Jun-Ting Huang Rui-Qing Cai Xiao-fei Sun 《Chinese Journal of Cancer》 SCIE CAS CSCD 2015年第11期531-537,共7页
Introduction: Brain metastasis is common in relapsed neuroblastoma patients, but the characteristics of brain metastasis remain largely unknown. This study aimed to investigate the status of brain metastasis with neur... Introduction: Brain metastasis is common in relapsed neuroblastoma patients, but the characteristics of brain metastasis remain largely unknown. This study aimed to investigate the status of brain metastasis with neuroblastoma in South China.Methods: In this retrospective case?based study, 106 patients with stage 4 neuroblastoma from the Department of Pediatric Oncology in Sun Yat?sen University Cancer Center between January 2004 and May 2013 were included. The incidence, risk factors, and survival status of these patients were reviewed and analyzed.Results: Of the 106 patients, 11(10.4%) developed brain metastasis, accounting for 20.0% of 55 patients with relapse or progression. The age at initial diagnosis of the 11 patients ranged from 2 to 10 years(median 4 years), which was younger than that of the patients without brain metastasis(median 5 years, range 1–10 years, P = 0.073). The male to female ratio of the 11 patients was 8:3, which was not signiicantly diferent from that of the patients with?out brain metastasis(P = 0.86). Patients with brain metastasis had higher lactate dehydrogenase levels than those without brain metastasis, but the diferences were not signiicant(P initial diagnosis to the develo= 0.076). Eight patients died, and 3 patients survived. The median interval from thepment of brain metastasis was 18 months(range 6–32 months). The median survival was 4 months(range 1 day to 29 months) after the diagnosis of brain metastasis. The median interval from the manifestation of brain metastasis to death was 3 months(range 1 day to 11 months).Conclusions: High?risk factors for brain metastasis in cases of neuroblastoma include bone marrow involvement and a younger age at initial diagnosis. Nevertheless, multiple treatment modalities can improve disease?free survival. 展开更多
关键词 Neuroblastoma POST treatment BRAIN metastasis STAGE 4
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Symmetry breaking of photonic spin-orbit interactions in metasurfaces 被引量:8
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作者 fei zhang Mingbo Pu +2 位作者 Jun Luo Honglin Yu Xiangang Luo 《光电工程》 CAS CSCD 北大核心 2017年第3期319-325,共7页
Spin-orbit optical phenomena pertain to the wider class of electromagnetic effects originating from the interaction of the photon spin with the spatial structure and propagation characteristics of an optical wave,medi... Spin-orbit optical phenomena pertain to the wider class of electromagnetic effects originating from the interaction of the photon spin with the spatial structure and propagation characteristics of an optical wave,mediated by suitable optical media.There are many emerging photonic applications of spin-orbit interactions(SOI)of light,such as control of the optical wave propagation via the spin,enhanced optical manipulation,and generation of structured optical fields.Unfortunately,current applications are based on symmetric SOI,that is,the behaviours of polarized photons with two opposite spins are opposite,leading to the limit of spin-based multiplexers.The symmetry of SOI can be broken in our proposed metasurfaces,consisting of spatially varying birefringence,which can arbitrarily and independently build SOI for two opposite spins without reduction of optical energy usage.We obtain three kinds of dual-functional metasurfaces at visible and infrared wavelengths with high efficiency.Our concept of generation of asymmetric SOI for two spins,using anisotropic metasurfaces,will open new degrees of freedoms for building new types of spin-controlled multifunctional shared-aperture devices for the generation of complex structured optical fields. 展开更多
关键词 metasurfaces METAMATERIALS spin-orbit interactions
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Crosstalk-free achromatic full Stokes imaging polarimetry metasurface enabled by polarization-dependent phase optimization 被引量:6
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作者 Yaxin zhang Mingbo Pu +10 位作者 Jinjin Jin Xinjian Lu Yinghui Guo Jixiang Cai fei zhang Yingli Ha Qiong He Mingfeng Xu Xiong Li Xiaoliang Ma Xiangang Luo 《Opto-Electronic Advances》 SCIE EI CAS 2022年第11期16-28,共13页
Imaging polarimetry is one of the most widely used analytical technologies for object detection and analysis.To date,most metasurface-based polarimetry techniques are severely limited by narrow operating bandwidths an... Imaging polarimetry is one of the most widely used analytical technologies for object detection and analysis.To date,most metasurface-based polarimetry techniques are severely limited by narrow operating bandwidths and inevitable crosstalk,leading to detrimental effects on imaging quality and measurement accuracy.Here,we propose a crosstalkfree broadband achromatic full Stokes imaging polarimeter consisting of polarization-sensitive dielectric metalenses,implemented by the principle of polarization-dependent phase optimization.Compared with the single-polarization optimization method,the average crosstalk has been reduced over three times under incident light with arbitrary polarization ranging from 9μm to 12μm,which guarantees the measurement of the polarization state more precisely.The experimental results indicate that the designed polarization-sensitive metalenses can effectively eliminate the chromatic aberration with polarization selectivity and negligible crosstalk.The measured average relative errors are 7.08%,8.62%,7.15%,and 7.59%at 9.3,9.6,10.3,and 10.6μm,respectively.Simultaneously,the broadband full polarization imaging capability of the device is also verified.This work is expected to have potential applications in wavefront detection,remote sensing,light-field imaging,and so forth. 展开更多
关键词 metasurface broadband achromatic crosstalk-free full polarization imaging polarimetry
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