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Exploring charge and spin fluctuations in infinite-layer cuprate SrCuO_(2)from a phonon perspective

Science China(Physics,Mechanics & Astronomy) 2024年第8期67卷 159-167页

作者： xin Du pei-Han Sun Ben-Chao Gong Jian-Feng Zhang Zhong-Yi lu Kai Liu Department of Physics and Beijing Key Laboratory of Opto-electronic Functional Materials&Micro-nano Devices Renmin University of ChinaBeijing 100872China Department of Physics School of ScienceJiangsu University of Science and TechnologyZhenjiang 212100China Institute of Physics Chinese Academy of SciencesBeijing 100190China Key Laboratory of Quantum State Construction and Manipulation(Ministry of Education) Renmin University of ChinaBeijing 100872China

The infinite-layer cuprate ACu O_(2)(A=Ca,Sr,Ba)possesses the simplest crystal structure among numerous cuprate superconductors and can serve as a prototypical system to explore the unconventional *** on the first-principles electronic structure calculations,we have studied the electronic and magnetic properties of the infinite-layer cuprate SrCuO_(2)from a phonon *** find that interesting fluctuations of charges,electrical dipoles,and local magnetic moments can be induced by the atomic displacements of phonon modes in SrCuO_(2)upon the hole *** all optical phonon modes of SrCuO_(2)in the antiferromagnetic Néel state,only the A_(1g)mode that involves the full-breathing O vibrations along the Cu-O bonds can cause significant fluctuations of local magnetic moments on O atoms and dramatic charge redistributions between Cu and O ***,due to the atomic displacements of the A_(1g)mode,both the charge fluctuations on Cu and the electrical dipoles on O show a dome-like evolution with increasing hole doping,quite similar to the experimentally observed behavior of the superconducting T_(c);in comparison,the fluctuations of local magnetic moments on O display a monotonic enhancement along with the hole *** analyses indicate that around the optimal doping,there exists a large softening in the frequency of the A_(1g)phonon mode and a van Hove singularity in the electronic structure close to the Fermi level,suggesting potential electron-phonon *** work reveals the important role of the full-breathing O phonon mode playing in the infinite-layer SrCuO_(2),which may provide new insights in understanding the cuprate superconductivity.

关键词： first-principles calculations cuprate superconductors phonon charge and spin fluctuations

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Hierarchical Voronoi Structure Inspired by Cat Paw Pads Substantially Enhances Landing Impact Energy Dissipation

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Journal of Bionic Engineering 2024年第4期21卷 1847-1861页

作者： Da lu Baoqing pei Yangyang Xu Mengyuan Hu Shijia Zhang Le Zhang xin Huang Yangwei Wang Xueqing Wu Beijing Key Laboratory for Design and Evaluation Technology of Advanced Implantable&Interventional Medical Devices Beijing Advanced Innovation Center for Biomedical EngineeringSchool of Biological Science and Medical EngineeringBeihang University100083BeijingChina National Key Laboratory of Science and Technology on Materials under Shock and Impact Beijing Institute of Technology100081BeijingChina Shenzhen Institute of Beihang University 518000ShenzhenChina

When a human lands from a high drop,there is a high risk of serious injury to the lower *** the other hand,cats can withstand jumps and falls from heights without being fatally wounded,largely due to their impact-resistant paw *** aim of the present study was to investigate the biomechanism of impact resistance in cat paw pads,propose an optimal hierarchical Voronoi structure inspired by the paw pads,and apply the structure to bionic cushioning shoes to reduce the impact force of landing for *** microstructure of cat paw pads was observed via tissue section staining,and a simulation model was reconstructed based on CT to verify and optimize the structural cushioning *** distribution pattern,wall thickness of compartments,thickness ratio of epidermis and dermis,and number of compartments in the model were changed and simulated to achieve an optimal composed structure.A bionic sole was 3D-printed,and its performance was evaluated via compression test and a jumping-landing *** results show that cat paw pads are a spherical cap structure,divided from the outside to the inside into the epidermis,dermis,and compartments,each with different cushioning capacities.A finite element simulation of different cushioning structures was conducted in a cylinder with a diameter of 20 mm and a height of 10 mm,featuring a three-layer *** optimal configuration of the three layers should have a uniform distribution with 0.3–0.5 mm wall thickness,a 1:1–2 thickness ratio of epidermis and dermis,and 100–150 compartments.A bionic sole with an optimized structure can reduce the peak impact force and delay the peak arrival *** energy absorption rate is about 4 times that of standard *** jumping 80,100,and 120 cm,the normalized ground reaction force is also reduced by 8.7%,12.6%and 15.1%compared with standard *** study provides theoretical and technical support for effective protection against human lower limb landing injuries.

关键词： Cat paw pads Hierarchical Voronoi structure Landing impact Energy dissipation Bionic sole

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Long-term Evolution of Solar Activity and Prediction of the Following Solar Cycles

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Research in Astronomy and Astrophysics 2024年第3期24卷 194-204页

作者： pei-xin luo Bao-Lin Tan National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China

Solar activities have a great impact on modern high-tech systems,such as human aerospace activities,satellite communication and navigation,deep space exploration,and related scientific ***,studying the long-term evolution trend of solar activity and accurately predicting the future solar cycles are highly *** on the wavelet transform and empirical function fitting of the longest recorded data of the annual average relative sunspot number(ASN)series of 323 yr to date,this work decisively verifies the existence of the solar century cycles and confirms that its length is about 104.0 yr,and the magnitude has a slightly increasing trend on the timescale of several hundred *** on this long-term evolutionary trend,we predict solar cycles 25 and26 by using phase similar prediction *** for solar cycle 25,its maximum ASN will be about146.7±33.40,obviously stronger than solar cycle *** peak year will occur approximately in 2024,and the period will be about 11±1 *** for solar cycle 26,it will start around 2030,and reach its maximum between2035 and 2036,with maximum ASN of about 133.0±3.200,and period of about 10 yr.

关键词： Sun activity-Sun evolution-(Sun) sunspots-methods data analysis

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Effects of Atmospheric Pressure Plasma in the Treatment of Experimental Periodontitis in Beagle Dogs

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Current Medical Science 2022年第5期42卷 1079-1087页

作者： Xue-zhi TANG Jia-yin LI Qi SHI Han-yong ZHANG Zhi-xiang ZHANG Ke SONG xin-pei lu Ying-guang CAO Tian-feng DU Department of Stomatology Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430030China State Key Laboratory of Advanced Electromagnetic Engineering and Technology School of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhan430074China Department of Stomatology The First Affiliated Hospital of Zhengzhou UniversityZhengzhou450052China

Objective The specific objective of this study was to evaluate the effects of atmospheric pressure plasma(APP)in the treatment of experimental periodontitis in Beagle *** The APP jet was diagnosed using optical emission spectroscopy and laser-induced fluorescence *** Beagles received stainless steel ligatures to establish experimental periodontitis *** teeth in the control group were subjected to conventional root surface debridement(RSD)and chlorhexidine *** APP group also started with RSD and was then subjected to plasma *** analyses including plaque index,modified sulcus bleeding index,pocket depth and attachment loss(AL),as well as cone-beam computed tomography(CBCT)analysis,were performed at baseline,4th week,8th week and 12th week after *** The results showed that typical reactive oxygen and nitrogen species were found in the full spectrum and the gas temperature of APP was close to room *** highest concentrations of hydroxide and oxygen were obtained at 5 mm away from the *** both groups,all values in clinical examinations were significantly lower(P<0.05)at 12th week after treatment than those at *** the 12th week,the AL in clinical examinations and the bone loss in CBCT images in the APP group were significantly lower than those in the control group(P<0.05).The hematoxylin-eosin staining showed more renascent alveolar bone in the APP group than in the control *** These findings suggested that APP has profound potential for use as an adjunct approach for periodontitis treatment.

关键词： canine plasma biofilms periodontitis therapeutics

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Carbon dots-derived three-dimensional-ordered macroporous host with high penetrability and catalytic activity for LSBs under lean electrolyte

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Rare Metals 2024年第6期43卷 2560-2573页

作者： Jiao-Zi Duan Hua-Yu pei Quan Yang Xue Li xin Ba Xue Yong Jun-Ling Guo Si-Yu lu Green Catalysis Center College of ChemistryZhengzhou UniversityZhengzhou 450001China Country State Center for International Cooperation On Designer Low-Carbon&Environmental Materials School of Materials Science and EngineeringZhengzhou UniversityZhengzhou 450001China Hubei Institute of Quality Supervision Inspection Wuhan 430061China Department of Chemistry University of SheffieldSheffeld S37HFUK

The practical energy density of lithium-sulfur batteries(LSBs)is seriously limited by the high electrolyte-to-sulfur ratios(E/S).The E/S can be reduced by employing hosts with easy-to-infiltrate structure that ensures the uniform distribution of a lean electrolyte and high catalytic activity that can suppress"shuttle effect"via accelerating the slow conversion of soluble poly sulfides to insoluble *** the easy-to-infiltrate structures,the three-dimensional-ordered macroporous(3DOM)structure is easier to scale preparation and more suitable for the existing industrial ***,it is difficult to obtain the 3DOM with(1)high penetrability due to the high viscosity of frequently-used organic polymer precursors and(2)high catalytic activity due to the low confinement effect,meaning that uniformly dispersed small-sized catalytic materials are difficult to load on ***,using carbon dots(CDs)with both organic and inorganic properties as a precursor and aggregation limiting agent,a 3DOM host with high penetrability and homodispersed Ni particles of small sizes(Ni-CDs-3DOM)was *** this host:(1)CDs precursor with suitable viscosity can improve the penetrability.(2)CDs can effectively inhibit the agglomeration of Ni particles.(3)Uniformly dispersed small-size Ni particles offer high-efficiency catalytic activity toward sulfur ***,the Ni-CDs-3DOM/sulfur cathode exhibits high sulfur utilization and stable cycling performance even under high sulfur loading(5.5 mg·cm^(-2))and low E/S(6.5μl·mg^(-1)).This work indicates the usefulness of CDs in constructing hosts for LSBs with high energy density.

关键词： Lithium-sulfur batteries Carbon dots Catalytic action Easy-to-infiltrate structure Lean electrolyte

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Spacelike Framed Curves with Lightlike Components and Singularities of Their Evolutes and Focal Surfaces in Minkowski 3-space

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Acta Mathematica Sinica,English Series 2024年第6期40卷 1521-1532页

作者： Peng Cheng LI Dong He pei xin ZHAO School of Mathematics and Statistics Northeast Normal UniversityChangchun 130024P.R.China Department of Mathematics Harbin Institute of TechnologyWeihai 264209P.R.China School of Mathematics and Statistics Qingdao UniversityQingdao 266071P.R.China

In this paper,we define the evolute and focal surface of a spacelike framed curve with lightlike components in Minkowski *** is a generalization of the previous results of regular spacelike curves,since singularities are allowed in the original spacelike curves studied by spacelike framed curves with lightlike ***,we show a new geometric invariant to characterise singularities of the focal ***,the classification theorem and recognition theorem for the singularities of the focal surface in generic are also given.

关键词： Evolutes focal surfaces spacelike framed curves singularities

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Polarization engineering in porous organic polymers for charge separation efficiency and its applications in photocatalytic aerobic oxidations

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Science China Chemistry 2024年第3期67卷 1000-1007页

作者： Kun Wu pei-Wen Cheng xin-Yi Liu Ji Zheng Xiao-Wei Zhu Mo Xie Puxin Weng Weigang lu Dan Li College of Chemistry and Materials Science Guangdong Provincial Key Laboratory of Functional Supramolecular Coordination Materials and ApplicationsJinan UniversityGuangzhou 510632China Guangdong Rare Earth Photofunctional Materials Engineering Technology Research Center School of Chemistry and EnvironmentJiaying UniversityMeizhou 514015China

Photocatalytic aerobic oxidation reactions are largely governed by the efficiency of charge separation and subsequent reactive oxygen species(ROS) generation. Herein, we report a polarization engineering strategy to promote the charge separation and ROS generation efficiency by substituting the benzene unit with furan/thiophene in porous organic polymers(POPs). Benefiting from the extent of local polarization, the thiophene-containing POP(JNU-218) exhibits the best photocatalytic performance in aerobic oxidation reactions, with a yield much higher than those for the furan-containing POP(JNU-217) and the benzenecontaining POP(JNU-216). Experimental studies and theoretical calculations reveal that the increase of local polarization can indeed reduce the exciton binding energy, and therefore facilitate the separation of electron-hole pairs. This work demonstrates a viable strategy to tune charge separation and ROS generation efficiency by modulating the dipole moments of the building blocks in porous polymeric organic semiconductors.

关键词： porous organic polymer local polarization photocatalytic aerobic oxidation charge separation reactive oxygen species exciton binding energy

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Kaempferol ameliorated levodopa-induced dyskinesia in experimental rats: A role of brain monoamines, cFOS, FosB, Parkin, Pdyn, TH, and p-JNK

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BIOCELL 2024年第3期48卷 513-523页

作者： pei QIN MIAO LIU xin WANG JIANHUA MA Geriatrics Department Chengde Central HospitalChengde067000China

Background:L-dopa(Levodopa)is well known for managing PD(Parkinson’s disease);however,its prolonged use caused dyskinesia(LID).Due to the varied presentation of LID,effective treatment options are *** reported their neuroprotective activity by ameliorating acetylcholinesterase,monoamine oxidase,and neuroinﬂ*** is anotherﬂavonoid bearing these ***:To evaluate neuroprotective activity of kaempferol in dyskinetic ***:PD was developed in Sprague-Dawley rats by injecting combination of L-ascorbic acid(10µL)+6-OHDA(12µg)in medial forebrain bundle to induce neuronal damage in substantial nigra(SNr).LID was induced by administrating combination of L-dopa(20 mg/kg)+benserazide HCl(5 mg/kg)for 42 *** were concomitantly treated with amantadine(40 mg/kg)or kaempferol(25,50,and 100 mg/kg,p.o.).Results:Kaempferol(50 and 100 mg/kg)markedly(pluntary movements(AIMs)and alternation in motor *** administration considerably(p<0.05)inhibited reduced mitochondrial complex activities,serotonin and dopamine levels,Bcl-2,and Tyrosine hydroxylase protein expressions in ***,kaempferol considerably(p<0.05)attenuated increased cFOS,FosB,Parkin,and Pdyn mRNAs expressions,Bax,cleaved caspase-3,caspase-3,and pJNK proteins levels;DOPAC and 5-HIAA levels in SNr.A positive correlation was reported between cFOS,FosB,Parkin,Pdyn,apoptosis,and TH with ***:Kaempferol effectively attenuated L-dopa-induced AIMs and dyskinesia via amelioration of alterations in cFOS,FosB,Parkin,Pdyn,Tyrosine hydroxylase,and apoptosis in the brain SNr.

关键词： AIMs cFOS Kaempferol Levodopa-induced dyskinesia Pdyn

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Imaging characteristics and treatment strategies for carotid artery occlusion caused by skull base fracture:Three case reports

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World Journal of Clinical Cases 2024年第15期12卷 2664-2671页

作者： pei-xin Shangguan Ke-Chun Zhou Department of Emergency Lishui Municipal Central HospitalLishui 323000Zhejiang ProvinceChina

BACKGROUND Traumatic internal carotid artery(ICA)occlusion is a rare complication of skull base fractures,characterized by high mortality and disability rates,and poor ***,timely discovery and correct management are crucial for saving the lives of such patients and improving their *** article retrospectively analyzed the imaging and clinical data of three patients,to explore the imaging characteristics and treatment strategies for carotid artery occlusion,combined with severe skull base *** SUMMARY This case included three patients,all male,aged 21,63,and 16 *** underwent plain film skull computed tomography(CT)examination at the onset of their illnesses,which revealed fractures at the bases of their ***,these cases were definitively diagnosed through CT angiography(CTA)*** first patient did not receive surgical treatment,only anticoagulation therapy,and recovered smoothly with no residual limb dysfunction(Case 1).The other two patients both developed intracranial hypertension and underwent decompressive *** of these patients had high intracranial pressure and significant brain swelling postoperatively,leading the family to choose to take him home(Case 2).The other patient also underwent decompressive craniectomy and recovered well postoperatively with only mild limb motor dysfunction(Case 3).We retrieved literature from PubMed on skull base fractures causing ICA occlusion to determine the imaging characteristics and treatment strategies for this type of *** For patients with cranial trauma combined with skull base fractures,it is essential to complete a CTA examination as soon as possible,to screen for blunt cerebrovascular injury.

关键词： Skull base fracture Traumatic internal carotid artery occlusion Blunt cerebrovascular injury Imaging Case report

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Drug-loading ZIF-8 for modification of microporous bone scaffold to promote vascularized bone regeneration

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Chinese Chemical Letters 2024年第6期35卷 358-364页

作者： xin Zhang Junyu Chen Xiang pei Linxin Yang Liang Wang luona Chen Guangmei Yang Xibo pei Qianbing Wan Jian Wang State Key Laboratory of Oral Diseases National Clinical Research Center for Oral DiseasesChengdu 610041China Department of Prosthodontics West China Hospital of StomatologySichuan UniversityChengdu 610041China

Surface modification of microporous bone scaffolds using nanoparticles has been broadly studied in bone tissue *** at improving vascularized bone regeneration(VBR),zeolitic imidazolate framework-8(ZIF-8)was encapsulated with dimethyloxallyl glycine(DMOG)and the drug-carrying nanoparticles(D@Z)could be uniformly coated onto the surface of the bone *** osteogenic and angiogenic actions of D@Z are closely correlated with the amount of slowly released DMOG,and in general,exhibited a favorable ***,the D7.5@Z group,which showed the greatest capacity to induce in vitro osteogenesis-angiogenesis coupling,was utilized for surface modification of the bone *** processes including phosphate-containing compound metabolic process,cell differentiation,cell proliferation and cell motility might contribute to enhanced ability to induce VBR by the coated scaffold and signaling pathways such as Rap1,Ras,phosphatidylinositol 3-kinase/protein kinase B(PI3K-AKT)and vascular endothelial growth factor(VEGF)signaling pathways participated in these ***,as depicted by in vitro real time-polymerase chain reaction(RT-PCR),Western blot(WB)and in vivo cranial bone defect model,the microporous scaffold coated with nano-D7.5@Z greatly promoted *** conclude,nano-D@Z has significant promise for practical application in modification of microporous bone scaffolds to enhance VBR,and DMOG loading quantity has a beneficial influence on D@Z to improve osteogenesis-angiogenesis coupling.

关键词： Drug-loading nanoparticles Surface coating Microporous bone scaffold Vascularization bone regeneration

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