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Cosmology-Independent Photon Mass Limits from Localized Fast Radio Bursts by Using Artificial Neural Networks

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Chinese Physics Letters 2024年第5期41卷 177-183页

作者：冉景遇王宝魏俊杰 Purple Mountain Observatory Chinese Academy of SciencesNanjing 210023China School of Astronomy and Space Sciences University of Science and Technology of ChinaHefei 230026China

A hypothetical photon mass m_(γ) can produce a frequency-dependent vacuum dispersion of light, which leads to an additional time delay between photons with different frequencies when they propagate through a fixed distance. The dispersion measure and redshift measurements of fast radio bursts(FRBs) have been widely used to constrain the rest mass of the photon. However, all current studies analyzed the effect of the frequency-dependent dispersion for massive photons in the standard ΛCdM cosmological context. In order to alleviate the circularity problem induced by the presumption of a specific cosmological model based on the fundamental postulate of the masslessness of photons, here we employ a new model-independent smoothing technique, artificial neural network(ANN), to reconstruct the Hubble parameter H(z) function from 34 cosmic-chronometer *** combining observations of 32 well-localized FRBs and the H(z) function reconstructed by ANN, we obtain an upper limit of m_(γ) ≤ 3.5 × 10^(-51)kg, or equivalently m_(γ) ≤ 2.0 × 10^(-15)eV/c^(2)(m_(γ) ≤ 6.5 × 10^(-51)kg, or equivalently m_(γ) ≤ 3.6 × 10^(-15)eV/c_(2)) at the 1σ(2σ) confidence level. This is the first cosmology-independent photon mass limit derived from extragalactic sources.

关键词： dispersion limit Independent

Simultaneously optimizing exciton diffusion length and nonradiative energy loss in organic solar cells via ternary strategy

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Science China Chemistry 2024年第9期67卷 3004-3011页

作者： Huanxiang Jiang Hao Lu Zezhou Liang Yonghai Li Guangliu ran Chenyu Han Yuqiang Liu Hongxiang Li Xichang bao Zhishan Bo College of Textiles and Clothing State Key Laboratory of Bio-fibers and Eco-textiles Qingdao University Key Laboratory for Physical Electronics and devices of the Ministry of Education & Shaanxi Key Lab of Photonic Technique for InformationSchool of Electronics Science & Engineering Faculty of Electronic and Information Engineering Xi'an Jiaotong University Qingdao Institute of Bioenergy and Bioprocess Technology Chinese Academy of Sciences Laboratory of Solar Energy Shandong Energy Institute department of Physics and Applied Optics Beijing Area Major Laboratory Center for Advanced Quantum Studies Beijing Normal University College of Polymer Science and Engineering State Key Laboratory of Polymer Materials Engineering Sichuan University

Significant nonradiative energy loss and short exciton diffusion length in organic solar cells(OSCs) are two major obstacles to achieving state-of-the-art efficiencies. It is crucial to conduct a study on the intensive mechanism and improvement strategies for future breakthroughs in the efficiency of OSCs. In this work, nonradiative energy loss and exciton diffusion length are optimized simultaneously by incorporating a guest acceptor(LA15) to construct ternary OSC(d18:L8-BO:LA15). Firstly, LA15 exhibits excellent compatibility with the host acceptor L8-BO, and effectively improves the fluorescence quantum efficiency(FLQY),resulting in suppressed non-radiative energy loss. Moreover, LA15 effectively prolongs the fluorescent lifetime of the acceptor phase from 0.85 to 1.12 ns, leading to larger exciton diffusion length, which is beneficial for reducing geminate ***, the addition of LA15 optimizes the crystallinity of the active layer with amplified charge transport capacity. As a result,the optimized d18:L8-BO:LA15 device achieves ultralow nonradiative energy loss of 0.18 e V and improved fill factor(FF) with high efficiency up to 19.13%. These results highlight the crucial roles of regulating FLQYand exciton lifetime in achieving highefficiency OSCs.

关键词： organic solar cells nonradiative energy loss exciton lifetime exciton diffusion length

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亚硫酸钠-壳聚糖微粒对明胶膜结构和性能的影响

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食品工业科技 2024年第13期45卷 9-16页

作者：黄燃鲍士宝安徽师范大学生命科学学院安徽芜湖241002 安徽省重要生物资源保护与利用研究重点实验室安徽芜湖241002

本研究以明胶为成膜基质,添加亚硫酸钠-壳聚糖微粒制备亚硫酸钠-壳聚糖微粒/复合明胶膜,探究亚硫酸钠-壳聚糖微粒对明胶膜结构和性能的影响。对明胶膜进行厚度、水合性能、阻隔性能、力学性能、光学性能、热稳定性和抗氧化性的测定,并... 详细信息

本研究以明胶为成膜基质,添加亚硫酸钠-壳聚糖微粒制备亚硫酸钠-壳聚糖微粒/复合明胶膜,探究亚硫酸钠-壳聚糖微粒对明胶膜结构和性能的影响。对明胶膜进行厚度、水合性能、阻隔性能、力学性能、光学性能、热稳定性和抗氧化性的测定,并对其进行结构表征。结果表明,添加亚硫酸钠-壳聚糖微粒的明胶膜厚度显著降低(PdPPH自由基清除率由14.41%提高至65.05%,而膜的水蒸气透过率和断裂伸长率未发生明显变化。此外,亚硫酸钠-壳聚糖微粒与明胶分子之间具有较高的相容性,亚硫酸钠-壳聚糖微粒的加入改变了明胶膜的结构。综上所述,亚硫酸钠-壳聚糖微粒的加入能够在一定程度上改变明胶膜的结构、提高明胶膜的性能。本研究为抗氧化复合明胶膜的制备和应用提供一定的理论指导和数据参考。

关键词：明胶壳聚糖亚硫酸钠微粒复合明胶膜

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Extracellular vesicles derived from mesenchymal stem cells mediate extracellular matrix remodeling in osteoarthritis through the transport of microRNA-29a

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World Journal of Stem Cells 2024年第2期16卷 191-206页

作者： Fan Yang Wan-Qi Xiong Chen-Zhi Li Ming-Jian Wu Xiu-Zhi Zhang Chun-Xiao ran Zhen-Hao Li Yan Cui bao-Yi Liu de-Wei Zhao department of Orthopedics Affiliated Zhongshan Hospital of Dalian UniversityDalian 116001Liaoning ProvinceChina

BACKGROUNd Knee osteoarthritis(KOA)is a common orthopedic condition with an uncertain etiology,possibly involving genetics and *** like changes in chondrocyte microenvironment,oxidative stress,inflammation,and immune responses affect KOA ***-stage treatment options primarily target symptom *** stem cells(MSCs)show promise for treatment,despite *** research highlights microRNAs(miRNAs)within MSC-released extracellular vesicles that can potentially promote cartilage regeneration and hinder KOA *** suggests exosomes(Exos)as a promising avenue for future *** these findings emphasize the need for effective KOA progression management,further safety and efficacy validation for Exos is *** To explore miR-29a’s role in KOA,we’ll create miR-29a-loaded vesicles,testing for early treatment in rat *** Extraction of bone marrow MSC-derived extracellular vesicles,preparation of engineered vesicles loaded with miR-29a using ultrasonication,and identification using quantitative reverse transcription polymerase chain reaction;after establi-shing a rat model of KOA,rats were randomly divided into three groups:Blank control group injected with saline,normal extracellular vesicle group injected with normal extracellular vesicle suspension,and engineered extrace-llular vesicle group injected with engineered extracellular vesicle *** three groups evaluation,histological detection,and immunohistochemical detection to compare and evaluate the progress of various forms of *** General behavioral observation results showed that the extracellular vesicle group and engineered extracellular vesicle group had better performance in all four indicators of pain,gait,joint mobility,and swelling compared to the blank control ***,the engineered extracellular vesicle group had better pain relief at 4 wk and better knee joint mobility at 8 wk compared to the nor

关键词： Exosomes Osteoarthritis Mesenchymal stem cells MicroRNA-29a Intra-articular injection

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

Aptamer-Based Antibiotic Electrochemical detection Platform Using Portable Plastic Gold Electrode and Multichannel Chip

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Chinese Journal of Chemistry 2024年第2期42卷 171-176页

作者： Yin bao Kaiwei Cai Yichen Liu Bingling Li Changchun Institute of Applied Chemistry Chinese Academy of SciencesChangchunJilin 130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefeiAnhui 230026China

The development of accurate,rapid and practical electrochemical sensing technology for antibiotic detection has an important application prospect in many fields such as food safety,environmental monitoring,medical and health *** this research,kanamycin specific dNA aptamer and its partially complementary short chain were self-assembled onto the surface of an integrated portable plastic gold electrode(PGE)by Au-s bond,and a simple kanamycin electrochemical biosensor interface was *** the same time,the epoxy resin channel layer was designed,and the auxiliary instrument was set up independently in the laboratory,which could help to measure and analyze eight groups of samples automatically in *** quantitative analysis results showed that in 20 min,the sensor had a good linear relationship between the peak current change of square wave voltammetry and the negative logarithm of kanamycin concentration when kanamycin concentration was in the range of 1-10o0μmol/L,and the detection limit could reach 0.40μmol/*** addition,the discrimination could be achieved within 5 min in the real-time analysis *** sensor had a simple construction method,good selectivity and stability,and could be used for rapid or real-time detection of kanamycin residues in actual water samples,which provided a new direction for the practical detection of kanamycin in environmental watersamples.

关键词： Biosensor Aptamer Antibiotics Electroanalysis dNA

diagnosis of the Kinetic Energy of the“21·7”Extreme Torrential Rainfall Event in Henan Province,China

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Advances in Atmospheric Sciences 2024年第1期41卷 73-83页

作者： Xiuping YAO Ruoying LI Xiaohong bao Qiaohua LIU China Meteorological Administration Training Centre Beijing 100081China State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China College of Atmospheric Sciences Nanjing University of Information Science and TechnologyNanjing 210044China

An extreme torrential rain(ETR)event occurred in Henan Province,China,during 18-21 July *** on hourly rain-gauge observations and ERA5 reanalysis data,the ETR was studied from the perspective of kinetic energy(K),which can be divided into rotational wind(V_(R))kinetic energy(K_(R)),divergent wind kinetic energy(K_(d)),and the kinetic energy of the interaction between the divergent and rotational winds(K_(Rd)).According to the hourly precipitation intensity variability,the ETR process was divided into an initial stage,a rapid increase stage,and maintenance *** showed that the intensification and maintenance of ETR were closely related to the upper-level K,and most closely related to the upperlevel K_(R),with a correlation coefficient of up to *** particular,the peak value of hourly rainfall intensity lagged behind the K_(R) by 8 ***,diagnosis showed that K transformation from unresolvable to resolvable scales made the ETR increase *** meridional rotational wind(u_(R))and meridional gradient of the geopotential(φ)jointly determined the conversion of available potential energy(APE)to K_(R) through the barotropic process,which dominated the rapid enhancement of K_(R) and then caused the rapid increase in *** transportation of K by rotational wind consumed K_(R),and basically offset the K_(R) produced by the barotropic process,which basically kept K_(R) stable at a high value,thus maintaining the ETR.

关键词： extreme torrential rain rotational kinetic energy kinetic energy generation and transport barotropic process

Basic Research Advances in China on Embryo Implantation,Placentation,and Parturition

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Maternal-Fetal Medicine 2024年第1期6卷 37-49页

作者： Haili bao Haibin Wang Fujian Provincial Key Laboratory of Reproductive Health Research Department of Obstetrics and GynecologyThe First Affiliated Hospital of Xiamen UniversitySchool of MedicineXiamen UniversityXiamen 361102China State Key Laboratory of Vaccines for Infectious diseases Xiang An Biomedicine LaboratorySchool of MedicineXiamen UniversityXiamen 361102China

This review aimed to summarize the major progress in maternal-fetal medicine achieved by Chinese scientists in recent *** was systematically searched from January 2020 to November *** that reported the progress in embryo implantation,placentation,and parturition made by Chinese scientists in the last 3 years were *** milestone events during gestation,embryo implantation,endometrial decidualization,placentation,and parturition are pivotal to a successful *** implantation requires intricate interactions between implantation-competent blastocysts and receptive *** adapt to pregnancy,endometrial stromal cells transform into specialized decidual cells,which occur spontaneously under the influence of ovarian hormones in humans but require the presence of embryos in *** embryonic development,the placenta forms to support fetal growth until *** maternal-fetal interface is composed of diverse cell types,including endometrial decidual cells,placental trophoblast cells,endothelial cells,and various immune cells,a sophisticated interplay among which contributes to the maintenance of *** term,the uterus transitions from quiescence to contractility,in preparation for *** to these events lead to pregnancy-related disorders such as repeated implantation failure,recurrent pregnancy loss,preeclampsia,fetal growth restriction,preterm birth,and *** recent years,Chinese scientists have made prominent achievements in basic research on the aforementioned pregnancy *** scientists have made remarkable contributions to reproductive biology and maternal-fetal medicine research in recent years,highlighting future research directions in this field.

关键词： Embryo implantation decidualization Placentation Maternal-fetal interface Parturition

d-Orbital steered FeN_(4)moiety through N,S dual-site adjustation for zinc-air flow battery

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Journal of Energy Chemistry 2024年第5期92卷 8-15页

作者： Chunzhu bao Mingwei Tong Xueli Li Zhonghua Xiang State Key Laboratory of Organic-Inorganic Composites Beijing University of Chemical TechnologyBeijing 100029China

The implementation of pristine covalent organic polymer(CO_(2)P)with well-defined structure as air electrode may spark fresh vitality to rechargeable zinc-air flow batteries(ZAFBs),but it still remains challenges in synergistically regulating their electronic states and structural porosity for the great device ***,we conquer these issues by exploiting N and S co-doped graphene with COP rich in metal-ligand nitrogen to synergistically construct an effective catalyst for oxygen reduction reaction(ORR).Among them,the N and S co-doped sites with high electronegativity properties alter the number of electron occupations in the d orbital of the iron centre and form electron-transfer bridges,thereby boosting the selectivity of the ORR-catalysed four-electron ***,the introduction of COP materials aids the formation of pore interstices in the graphene lamellae,which both adequately expose the active sites and facilitate the transport of reactive *** from the synergistic effect,as-prepared catalyst exhibits excellent half-wave potentials(E_(1/2)=912 mV)and stability(merely 8.8%drop after a long-term durability test of 50000 s).Further,ZAFBs assembled with the N/SG@CO_(2)P catalyst demonstrate exceptional power density(163.8 mW cm^(-2))and continuous charge and discharge for approximately 140 h at 10 mA cm^(-2),outperforming the noble-metal benchmarks.

关键词： Nitrogen/sulfurdual sites Metal-coordinated nitrogen sites Covalent organic polymer Oxygen reduction reaction Zn-airflow battery