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Improved damage tolerance and oxidation resistance of (Ti_(0.2)Zr_(0.2)Hf_(0.2)Nb_(0.2)Ta_(0.2))b_(2)–Sic.b. introducing chopped carbon fibers

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Journal of Advanced ceramics 2024年第1期13卷 101-112页

作者： Feilong Huang Hailong Wang cheng Fang Mingliang Li Gang Shao Jinpeng Zhu Yanchun zhou School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450001China

High-entropy diborides(HEbs)are considered as promising high-temperature structure materials owing to their high melting point and excellent thermal ***,the intrinsic.b.ittleness is the main obstacle that seriously limits their practical *** overcome with this obstacle,carbon fibers(cf)with outstanding mechanical properties are used in the present work as a first attempt to improve the damage tolerance of *** as-prepared c_(f)/(Ti_(0.2)Zr_(0.2)Hf_(0.2)Nb_(0.2)Ta_(0.2))b_(2)–Sic composite(c_(f)/HEb–Sic)shows high relative density(97.9%)and good mechanical properties with flexural strength of 411±3 MPa and fracture toughness of 6.15±0.11 MPa·m^(1/2).More importantly,the damage tolerance parameter(Dt)has increased from 0.10 m^(1/2) for HEb–Sic to 0.29 m^(1/2) for c_(f)/HEb–*** microstructural analysis and Vickers indentation of the composite,the toughening mechanisms are *** carbon fibers coated with carbon coatings demonstrate unique capacity for prolonging the crack propagation path,which promotes the reliability of the composite ***,the c_(f)/(Ti_(0.2)Zr_(0.2)Hf_(0.2)Nb_(0.2)Ta_(0.2))b_(2)–Sic composite also exhibits good static oxidation resistance in the temperature range of 1100–1500℃in air due to the formation of the protective oxide layer constituting of multicomponent oxides(Zr)HfTiO4 and(Zr)Hf_(6)Ta_(2)O_(17) embedded in a continuous SiO_(2) *** results are promising,and this primary work can be used as a reference to the synthesis of c_(f)/HEbs for thermal protection materials under hightemperature serving conditions.

关键词： high-entropy ceramics carbon fibers(cf) toughening mechanisms oxidation resistance

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Reevaluation by the cRISPR/cas9 knockout approach revealed that multiple pluripotency-associated lncRNAs are dispensable for pluripotency maintenance while Snora73a/b is essential for pluripotency exit

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Science china Life Sciences 2024年第10期67卷 2198-2212页

作者： Zhen Li Xuefei Li Jingxia Lin Yangming Wang Huiqing cao Jiajian zhou Institute of Molecular Medicine College of Future TechnologyPeking University Dermatology Hospital Southern Medical University beijing Advanced center of RNA biology (bEAcON) Peking University

Many long noncoding RNAs(lncRNAs) have been identified through siRNA-based screening as essential regulators of embryonic stem cell(ESc) pluripotency. However, the biological and molecular functions of most lncRNAs remain unclear. Here, we employed cRISPR/cas9-mediated knockout technology to explore the functions of 8 lncRNAs previously reported to promote pluripotency in mouse EScs. Unexpectedly, all of these lncRNAs were dispensable for pluripotency maintenance and proliferation in mouse EScs when disrupted individually or in combination. Single-cell transcriptomic analysis also showed that the knockout of these lncRNAs has a minimal impact on pluripotency gene expression and cell identity. We further showed that several small hairpin RNAs(shRNAs) previously used to knock down lncRNAs caused the downregulation of pluripotency genes in the corresponding lncRNA-knockout EScs, indicating that off-target effects likely responsible for the pluripotency defects caused by these shRNAs. Interestingly, linc1343-knockout and linc1343-knockdown EScs failed to form cystic structures and exhibited high expression of pluripotency genes during embryoid body(Eb) differentiation. by reintroducing RNA products generated from the linc1343 locus, we found that two snoRNAs, Snora73a and Snora73b, but not lncRNAs, could rescue pluripotency silencing defects during Eb differentiation of linc1343 knockout EScs. Our results suggest that the 8 previously annotated pluripotency-regulating lncRNAs have no overt functions in conventional ESc culture; however, we identified snoRNA products derived from an annotated lncRNA locus as essential regulators for silencing pluripotency genes.

关键词： long noncoding RNAs embryonic stem cells cRISPR/cas9 snoRNAs stem cell differentiation

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Origin and tectonic setting of low-Si alkaline magma

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Science china Earth Sciences 2024年第5期67卷 1417-1435页

作者： Qiushi zhou Rui WANG State Key Laboratory of Geological Processes and Mineral Resources and Institute of Earth SciencesChina University of GeosciencesBeijing 100083China Frontiers Science center for Deep-time Digital Earth China University of Geosciences(Beijing)Beijing 100083China

Despite of the relatively rare occurrence of alkaline igneous rocks on Earth, they are the most diverse group of igneous rocks due to variations in their mineral assemblages and geochemical compositions. Alkaline igneous rocks are generally characterized by Si undersaturation, and K-Na(and in some cases c) enrichment. Although there is no unified alkaline igneous rock classification scheme, diagrams such as total alkalis-SiO_(2) or K_(2)O-SiO_(2) can be used to classify alkaline igneous rocks. The origins of silica-saturated alkaline rocks(SiO_(2)>52 wt.%) are relatively complex because multiple episodes of magmatism are often involved, therefore most studies have focused on the origins of silica-undersaturated alkaline *** experimental petrological studies have been conducted in the past few decades. Initially, it was considered that enrichment of trace elements was only achieved by low-degree partial melting of mantle peridotite, but the experimental melts could not reproduce the geochemical composition of natural alkaline igneous rocks. Subsequent studies have focused on carbonate-bearing eclogites that represent the average component of subducted oceanic crust. Although experimental studies indicate that silica-undersaturated and alkali-oversaturated melts can be generated from eclogites, some studies have considered that natural silica-undersaturated alkaline igneous rocks are the result of multi-stage source enrichment by incompatible elements. Low-degree partial melts of the mantle can be emplaced in the lithospheric mantle, forming veins consisting of phlogopite, amphibole, and pyroxene. Melting experiments including these components show that the produced melts better reproduce the naturally occurring silica-undersaturated alkaline magmas. Silica-deficient alkaline igneous rocks occur in various tectonic settings. Those in intraplate and divergent settings(i.e., mainly continental rifts) normally involve contributions from recycled components su

关键词： Alkaline igneous rock Tectonic setting Petrogenesis big data

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Secoemestrin c Ameliorates Psoriasis-like Skin Inflammation in Mice by Suppressing the TNF-α/NF-κb Signaling Pathway

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current Medical Science 2024年第1期44卷 232-240页

作者： Zhi-bin ZHU Meng-jie LIU Jing WANG zhou SHU Jie cAO Department of Stomatology Chengdu Seventh People's HospitalChengdu 610044China Department of Pharmacy Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022China

Objective Secoemestrin c(Sc),an epitetrathiodioxopiperazine isolated from Aspergillus nidulans,has been previously reported to have immunomodulatory and hepatoprotective effects against acute autoimmune ***,the effect of Sc on regulating the inflammation and its underlying mechanisms in the pathogenesis of psoriasis remain *** study aimed to evaluate the effects of Sc on inflammatory dermatosis both in vitro and in *** In vitro,HacaT cells were induced with tumor necrosis factor-alpha(TNF-α,10 ng/mL)to establish an inflammatory injury model,and the expression of nuclear transcription factor-κb(NF-κb)pathway components was measured using qRT-PcR and Western *** in vivo mouse model of imiquimod(IMQ)-induced psoriasis-like skin inflammation was used to evaluate the effectiveness of Sc in alleviating *** Sc significantly blocked the activation of NF-κb signaling in TNF-α-stimulated HacaT *** addition,systemic and local administration of Sc improved psoriatic dermatitis in the IMQ-induced mouse *** reduced skin scale and significantly inhibited the secretion of inflammatory factors in skin *** The protective effect of Sc against psoriatic-associated inflammation reveals its potential therapeutic value for treating psoriasis.

关键词： secoemestrin c(Sc) psoriasis tumor necrosis factor-alpha(TNF-α) nuclear transcription factor-kb(NF-kb) inflammation

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Neural-field-assisted transport-of-intensity phase microscopy: partially coherent quantitative phase imaging under unknown defocus distance

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Photonics Research 2024年第7期12卷 1494-1501页

作者： YANbO JIN LINPENG LU SHUN zhou JIE zhou YAO FAN cHAO ZUO Smart computational Imaging Laboratory(ScILab) School of Electronic and Optical EngineeringNanjing University of Science and TechnologyNanjing 210094China Smart computational Imaging Research Institute(ScIRI)of Nanjing University of Science and Technology Nanjing 210019China Jiangsu Key Laboratory of Spectral Imaging&Intelligent Sense Nanjing 210094China

The transport-of-intensity equation(TIE) enables quantitative phase imaging(QPI) under partially coherent illumination by measuring the through-focus intensities combined with a linearized inverse reconstruction algorithm. However, overcoming its sensitivity to imaging settings remains a challenging problem because of the difficulty in tuning the optical parameters of the imaging system accurately and because of the instability to long-time measurements. To address these limitations, we propose and experimentally validate a solution called neural-field-assisted transport-of-intensity phase microscopy(NFTPM) by introducing a tunable defocus parameter into neural field. Without weak object approximation, NFTPM incorporates the physical prior of partially coherent image formation to constrain the neural field and learns the continuous representation of phase object without the need for training. Simulation and experimental results of He La cells demonstrate that NFTPM can achieve accurate, partially coherent QPI under unknown defocus distances, providing new possibilities for extending applications in live cell biology.

关键词： field. coherent phase

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Layer Hall effect induced by hidden berry curvature in antiferromagnetic insulators

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National Science Review 2024年第2期11卷 15-23页

作者： Rui chen Hai-Peng Sun Mingqiang Gu chun-bo Hua Qihang Liu Hai-zhou Lu X.c.Xie Shenzhen Institute for Quantum Science and Engineering and Department of Physics Southern University of Science and Technology(SUSTech) International Quantum Academy Institute for Theoretical Physics and Astrophysics University of Würzburg School of Electronic and Information Engineering Hubei University of Science and Technology Guangdong Provincial Key Laboratory of computational Science and Material Design Southern University of Science and Technology Shenzhen Key Laboratory of Quantum Science and Engineering International center for Quantum Materials School of PhysicsPeking University collaborative Innovation center of Quantum Matter cAS center for Excellence in Topological Quantum computation University of Chinese Academy of Sciences

The layer Hall effect describes electrons spontaneously deflected to opposite sides at different layers, which has been experimentally reported in the Mnbi2Te4thin films under perpendicular electric fields. Here, we reveal a universal origin of the layer Hall effect in terms of the so-called hidden berry curvature, as well as material design principles. Hence, it gives rise to zero berry curvature in momentum space but non-zero layer-locked hidden berry curvature in real space. We show that, compared to that of a trivial insulator, the layer Hall effect is significantly enhanced in antiferromagnetic topological insulators. Our universal picture provides a paradigm for revealing the hidden physics as a result of the interplay between the global and local symmetries, and can be generalized in various scenarios.

关键词： layerHall effect hidden berry curvature antiferromagnetic insulator axion insulator, quantum transport

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Small cycles Property of Some cremer Rational Maps and Polynomials

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chinese Annals of Mathematics,Series b 2024年第1期45卷 123-136页

作者： Rong FU Ji zhou Faculty of Science Yibin UniversityYibin 644000SichuanChina Department of Mathematical Sciences Sichuan Normal UniversityChengdu 610066China

This paper concerns the linearization problem on rational maps of degree d≥2 and polynomials of degree d>2 from the perspective of *** authors introduce a set l_(∞) of irrational numbers and show that if α∈l_(∞),then any rational map is not linearizable and has infinitely many cycles in every neighborhood of the fixed point with multiplier λ=e^(2πiα),Adding more constraints to c.b.c polynomials,they discuss the above problems by polynomial-like *** the family of polynomials,with the help of Yoccoz's method,they obtain its maximum dimension of the set in which the polynomials are non-linearizable.

关键词： Irrationally indifferent fixed point Linearization problem Small cycles property

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Effects of lighting conditions and accommodation on the three-dimensional position of Visian implantable collamer lens

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Eye and Vision 2024年第3期10卷 31-40页

作者： Lingling Niu Zhe Zhang Huamao Miao Jing Zhao Xiaoying Wang Ji c.He Xingtao zhou Department of Ophthalmology and Optometry Eye&ENT HospitalFudan UniversityShanghaiChina NHc Key Laboratory of Myopia(Fudan University) ShanghaiChina Key Laboratory of Myopia Chinese Academy of Medical SciencesShanghaiChina Shanghai Research center of Ophthalmology and Optometry ShanghaiChina New England college of Optometry MABostonUSA

background To investigate the effects of lighting conditions and accommodation on the three-dimensional position of Visian implantable collamer lens(IcL V4c).Methods This observational study recruited 62 eyes of 31 myopia patients underwent IcL V4c *** segment optical coherence tomography(AS-OcT)assessed the anterior chamber depth(AcD),AcD-IcL(distance from the corneal endothelium to anterior surface of the IcL V4c),vault(distance between the posterior IcL V4c surface and anterior crystalline lens surface),and crystalline lens tilt under various lighting conditions and accommodation relative to the corneal topographic axis at one year after IcL V4c *** was defined as the scotopic condition,which was also the non-accommodative stimulus *** IcL V4c tilt was analyzed using *** significance level was set at PcD-IcL values were similar under various lighting conditions(P=0.978)but decreased during accommodation(Pcantly smaller under mesopic and photopic conditions than the baseline(P=0.044 and Pctively)but remained unchanged during accommodation(P=0.058).The inferotemporal proportion of IcL V4c(88.7%,55 eyes)and crystalline lens(74.2%,46 eyes)tilts were not significantly different(P=0.063).crystalline lens under various lighting conditions and accommodation exhibited similar *** vertical tilt of IcL V4c was significantly larger under photopic conditions than the baseline(P=0.038).The horizontal and total tilts were significantly decreased during accommodation(P=0.043 and 0.013,respectively).conclusions The axial position of IcL V4c in the anterior chamber was stable under various lighting *** conditions and accommodation may influence vertical,horizontal and total tilts of IcL V4c.

关键词： Implantable collamer lens Anterior segment optical coherence tomography Myopia Tilt

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cardiac infiltration of diffuse large b-cell lymphoma manifesting as sustained ventricular tachycardia:a case report

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Journal of Geriatric cardiology 2024年第2期21卷 242-245页

作者： Wei cHEN Kun HUANG Wei-Wei GUO Fan zhou De-Ning LIAO Department of cardiology Shanghai Jingan District Zhabei Central HospitalShanghaiChina Department of cardiology Shanghai Changzheng HospitalShanghaiChina Department of Hematology Shanghai Jingan District Zhabei Central HospitalShanghaiChina

cardiac tumors are ***,cardiac metastases can occur in up to 10%of patients with *** cardiac neoplasms,metastases are much more common than primary cardiac tumors.[1]Metastatic cardiac neoplasms most frequently metast... 详细信息

关键词： neoplasms sustained cardiac

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Source apportionment of PM_(2.5)using PMF combined online bulk and single-particle measurements:contribution of fireworks and biomass burning

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Journal of Environmental Sciences 2024年第2期136卷 325-336页

作者： Yanjing Zhang Wenshuai Li Lei Li Mei Li Zhen zhou Jianzhen Yu Yang zhou Frontier Science center for Deep Ocean Multispheres and Earth System(FDOMES)and Physical Oceanography Laboratory Ocean University of ChinaQingdaoShandong 266100China college of Oceanic and Atmospheric Sciences Ocean University of ChinaQingdaoShandong 266100China Institute of Atmospheric Environment Safety and Pollution control Jinan UniversityGuangdong 510632China Institute of Environment Hong Kong University of Science and TechnologyClear Water BayKowloonHong KongChina Department of chemistry Hong Kong University of Science and TechnologyClear Water BayKowloonHong KongChina Division of Environment The Hong Kong University of Science and TechnologyClear Water BayKowloonHong KongChina

Fireworks(FW)could significantly worsen air quality in short term during *** to similar tracers with biomass burning(bb),the fast and precise qualification of FW and bb is still *** this study,online bulk and single-particle measurements were combined to investigate the contributions of FW and bb to the overall mass concentrations of PM_(2.5)and specific chemical species by positive matrix factorization(PMF)during the chinese New Year in Hong Kong in February *** combined information,fresh/aged FW(abundant ^(140)K_(2)NO_(3)^(+)and ^(213)K_(3)SO_(4)^(+)formed from ^(113)K_(2)cl^(+)discharged by fresh FW)can be extracted from the fresh/aged bb sources,in addition to the Second Aerosol,Vehicles+Road Dust,and Sea Salt *** contributions of FW and bb were investigated during three high particle matter episodes influenced by the pollution transported from the Pearl River Delta *** fresh bb/FW contributed 39.2%and 19.6%to PM_(2.5)during the Lunar chinese New Year ***,the contributions of aged FW/bb enhanced in the last two episodes due to the aging process,evidenced by high contributions from secondary ***,the fresh bb/FW showed more significant contributions to nitrate(35.1%and15.0%,respectively)compared with sulfate(25.1%and 5.9%,respectively)and Oc(14.8%and11.1%,respectively)on *** comparison,the aged FW contributed more to sulfate(13.4%).Overall,combining online bulk and single-particle measurement data can combine both instruments’advantages and provide a new perspective for applying source apportionment of aerosols using PMF.

关键词： Source apportionment PMF Online bulk measurements Single particle analysis Fireworks biomass burning

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