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Resolution Enhancement of SOHO/MDI Magnetograms

Research in Astronomy and Astrophysics 2024年第6期24卷 360-369页

作者： ying Qin kai-Fan Ji Hui liu Xiao-Guang Yu Yunnan Observatories Chinese Academy of Sciences University of Chinese Academy of Sciences Yunnan Key Laboratory of Solar Physics and Space Science Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of Sciences

Research on the solar magnetic field and its effects on solar dynamo mechanisms and space weather events has benefited from the continual improvements in instrument resolution and measurement frequency. The augmentation and assimilation of historical observational data timelines also play a significant role in understanding the patterns of solar magnetic field variation. Within the realm of astronomical data processing,super-resolution(SR) reconstruction refers to the process of using a substantial corpus of training data to learn the nonlinear mapping between low-resolution(LR) and high-resolution(HR) images, thereby achieving higherresolution astronomical images. This paper is an application study in high-dimensional nonlinear regression. Deep learning models were employed to perform SR modeling on SOHO/MDI magnetograms and SDO/HMI magnetograms, thus reliably achieving resolution enhancement of full-disk SOHO/MDI magnetograms and enhancing the image resolution to obtain more detailed information. For this study, a data set comprising 9717pairs of data from 2010 April to 2011 February was used as the training set, 1332 pairs from 2011 March were used as the validation set and 1034 pairs from 2011 April were used as the test set. After data preprocessing, we randomly cropped 128 × 128 sub-images as the LR cases from the full-disk MDI magnetograms, and the corresponding 512 × 512 sub-images as HR ones from the HMI full-disk magnetograms for model training. The tests conducted have shown that the study successfully produced reliable 4× SR reconstruction of full-disk MDI magnetograms. The MESR model's results(0.911) were highly correlated with the target HMI magnetographs as indicated by the correlation coefficient values. Furthermore, the method achieved the best PSNR, SSIM, MAE and RMSE values, indicating that the MESR model can effectively reconstruct magnetograms.

关键词： magnetic fields Sun: magnetic fields techniques: image processing virtual observatory tools

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Incorporation sodium ions into monodisperse lead-free double perovskite Cs_(2)AgBiCl_(6) nanocrystals to improve optical properties

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Chinese Chemical Letters 2024年第3期35卷 549-553页

作者： Song Wang ying Xie Wenchao Jiang Binghang liu Keying Shi kai Pan Key Laboratory of Functional Inorganic Material Chemistry Ministry of EducationHeilongjiang UniversityHarbin 150080China School of Materials Science and Engineering Jiangsu Engineering Laboratory of Light-Electricity-Heat Energy-Converting Materials and ApplicationsChangzhou UniversityChangzhou 213164China State Key Laboratory of Catalysis Dalian National Laboratory for Clean EnergyDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China

Lead-free double perovskite nanocrystals(NCs)have emerged as a promising candidate in the optical field,owing to their non-toxic,good moist heat and chemical stability.However,their poor optical properties limited their application.To improve the optical properties of lead-free double perovskite NCs,metal ion doping or alloying had been suggested as a promising strategy.Here,we prepared monodisperse,uniformly sized,cubic morphology of Cs_(2)AgBiCl_(6)NCs with different Na^(+)incorporation amounts via a simple hot-injection method.The Na^(+)incorporation broke the parity-forbidden transition by reducing the inversion symmetry of the electron wave function at the Ag site,which changed the parity of the self-trapped exciton wave function and thus allowed radiative recombination.As a result,the photoluminescence quantum yield(PLQY)of Na^(+)-alloyed Cs_(2)AgBiCl_(6)NCs(12.1%)was higher than that of Cs_(2)AgBiCl_(6)NCs(2.4%),and the exciton lifetime of Na^(+)-alloyed Cs_(2)AgBiCl_(6)NCs increased to 36.98 ns from 17.58 ns for Cs_(2)AgBiCl_(6)NCs.By adjusting the amount of Na^(+)incorporation,the band gap of Cs_(2)AgBiCl_(6)NCs can be significantly tuned from~2.90 eV to~3.50 eV.Furthermore,the temperature-dependent photoluminescence spectra indicated that the Na^(+)-alloyed Cs_(2)AgBiCl_(6)NCs possessed higher longitudinal optical phonon energy and exciton binding energy compared to Cs_(2)AgBiCl_(6)NCs.This suggested that there were strong exciton-phonon interactions during exciton recombination,a reduced probability of non-radiative processes,and excellent thermal stability.It offers a promising strategy for improving the optical properties of lead-free double perovskite NCs,and have the potential to replace traditional lead halide perovskite NCs in future optoelectronic applications.

关键词： Nanocrystals Alloy Double perovskites Optical properties Exciton binding energy

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Neighborhood predictors of short sleep duration and bedtime irregularity among children in the United States: results from the 2019-2020 National Surveyof Children's Health

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World Journal of Pediatrics 2024年第1期20卷 73-81页

作者： ying Dai Jianghong liu School of Nursing University of Pennsylvania418 Curie Blvd.Room 426Claire M.Fagin HallPhiladelphiaPA19104-6096USA

Background Environmental factors may contribute to short sleep duration and irregular bedtime in children.Neighborhood factors and children's sleep duration and bedtime regularity remain a less investigated area.The aim of this study was to investigate the national and state-level proportions of children with short sleep duration and irregular bedtime and their neighborhood predictors.Methods A total of 67,598 children whose parents completed the National Survey of Children's Health in 2019-2020 were included in the analysis.Survey-weighted Poisson regression was used to explore the neighborhood predictors of children's short sleep duration and irregular bedtime.Results The prevalence of short sleep duration and irregular bedtime among children in the United States(US)was 34.6%[95%confidence interval(CI)=33.8%-35.4%]and 16.4%(95%CI=15.6%-17.2%)in 2019-2020,respectively.Safe neighborhoods,supportive neighborhoods,and neighborhoods with amenities were found to be protective factors against children's short sleep duration,with risk ratios ranging between 0.92 and 0.94,P<0.05.Neighborhoods with detracting elements were associated with an increased risk of short sleep duration[risk ratio(RR)=1.06,95%CI=1.00-1.12]and irregular bedtime(RR=1.15,95%CI=1.03-1.28).Child race/ethnicity moderated the relationship between neighborhood with amenities and short sleepduration.Conclusions Insufficient sleep duration and irregular bedtime were highly prevalent among US children.A favorable neighborhood environment can decrease children's risk of short sleep duration and irregular bedtime.Improving the neighborhood environment has implications for children's sleep health,especially for children from minority racial/ethnic groups.

关键词： Child National Survey of Children's Health Neighborhood.Sleep Social determinants of health

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Hydrogen and nitrogen absorption properties of Ce-added Zr_(2)(Fe_(1-x)Ni_(x)) alloys

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Journal of Rare Earths 2024年第6期42卷 1136-1141,I0005页

作者： kai Yin Xiaopeng liu State Key Laboratory of Advanced Materials for Smart Sensing GRINM Group Co.Ltd.Beijing10088China GRIMAT Engineering Institute Co. Ltd.Beijing101407China General Research Institute of Nonferrous Metals Beijing100088China

To improve the nitriding resistance of Zr_(2)Fe alloy,the Ce-added Zr_(2)(Fe_(1-x)Ni_(x))(x=0,0.15,0.3,0.5)alloys were prepared by magnetic levitation melting method.The effects of Ni substitution for Fe on the phase structure,hydrogen and nitrogen absorption properties of the alloys were investigated by X-ray diffraction,scanning electron microscopy and p-c isotherm measurements.The experimental results show that Ni substitution can effectively inhibit the formation of both α-Zr and ZrFe_(2) phases and promote the formation of C16 structure Zr_(2)(Fe,Ni)phase,causing Ni-substituted alloys to exhibit low nitrogen absorption rate and capacity.At 623 K under 0.5 MPa nitrogen pressure,the nitrogen absorption capacity of Ce-added Zr_(2)(Fe_(0.5)Ni_(0.5))alloy reaches to 0.8 mL/g,much lower than that of Zr_(2)Fe alloy(1.5 mL/g).Ni substitution decreases the crystal cell volume of the C_(16)Zr_(2)(Fe,Ni)phase,resulting in an increase in the hydrogen absorption equilibrium pressure.At 623 K under 0.05 MPa hydrogen pressure,the hydrogen absorption capacity decreases from 1.46 wt%of Zr_(2)Fe alloy to 1.41 wt%of Ce-added Zr_(2)(Fe_(0.5)Ni_(0.5))alloy.

关键词： Zr_(2)Fe alloy Ce Pressure-composition isotherm Hydrogen absorption Nitrogen absorption Rare earths

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Identifying coronary artery bypass grafting patients at high risk for adverse long-term prognosis using serial health-related quality of life assessments

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中华医学杂志(英文版) 2024年第9期137卷 1069-1077页

作者： Wang Juncheng liu Hanning Yue Chao Yang Limeng Yang kai Zhao Yan Ren Huan Zhang ying Zheng Zhe National Clinical Research Center for Cardiovascular Diseases State Key Laboratory of Cardiovascular Disease Fuwai Hospital National Center for Cardiovascular Diseases Chinese Academy of Medical Sciences and Peking Union Medical College Beijing China Department of Cardiovascular Surgery Fuwai Hospital National Center for Cardiovascular Diseases Chinese Academy of Medical Sciences and Peking Union Medical College Beijing China Department of Vascular Surgery Fuwai Hospital National Center for Cardiovascular Diseases Chinese Academy of Medical Sciences and Peking Union Medical College Beijing China Department of Cardiac Surgery Wuhan Asia Heart Hospital Wuhan Hubei China

Background: Patients who undergo coronary artery bypass grafting (CABG) are known to be at a significant risk of experiencing long-term adverse events, emphasizing the importance of regular assessments. Evaluating health-related quality of life (HRQoL) serves as a direct method to gauge prognosis. Our objective is to ascertain the prognostic significance of consecutive HRQoL assessments using the Physical Component Summary (PCS) and Mental Component Summary (MCS) derived from the Short-Form 36 (SF-36) health survey in CABG patients.Methods: The study population consisted of 433 patients who underwent isolated elective CABG at Fuwai Hospital between 2012 and 2013. SF-36 assessments were conducted during both the hospitalization period and follow-up. The primary endpoint of the study was all-cause mortality, while the secondary outcome was a composite measure including death, myocardial infarction, stroke, and repeat revascularization. We assessed the relationships between the PCS and MCS at baseline, as well as their changes during the first 6 months after the surgery (referred to as ΔPCS and ΔMCS, respectively), and the observed outcomes.Results: The patients were followed for an average of 6.28 years, during which 35 individuals (35/433, 8.1%) died. After adjusting for clinical variables, it was observed that baseline MCS scores (hazard ratio [HR] for a 1-standard deviation [SD] decrease, 1.57; 95% confidence interval [CI], 1.07–2.30) and ΔMCS (HR for a 1-SD decrease, 1.67; 95% CI, 1.09–2.56) were associated with all-cause mortality. However, baseline PCS scores and ΔPCS did not exhibit a significant relationship with all-cause mortality. Notably, there was a dose-response relationship observed between ΔMCS and the likelihood of all-cause mortality (HRs for the 2nd, 3rd and 4th quartiles compared to the 1st quartile, 0.33, 0.45 and 0.11, respectively).Conclusions: Baseline MCS and changes in MCS were independent predictors for long-term mortality of CABG. Better mental health status and recovery indicated better

关键词： Coronary artery bypass grafting Coronary artery disease Prognosis Quality of life Short-Form 36 Risk factor Serial measurements

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Non-coding RNAs expression in SARS-CoV-2 infection:pathogenesis,clinical significance,and therapeutic targets

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Signal Transduction and Targeted Therapy 2024年第1期9卷 55-78页

作者： Xiaoxing liu Wandi Xiong Maosen Ye Tangsheng Lu kai Yuan Suhua Chang ying Han Yongxiang Wang Lin Lu Yanping Bao Peking University Sixth Hospital Peking University Institute of Mental HealthNHC Key Laboratory of Mental Health(Peking University)National Clinical Research Center for Mental Disorders(Peking University Sixth Hospital)100191 BeijingChina Peking-Tsinghua Center for Life Sciences and PKU-IDG/McGovern Institute for Brain Research Peking University100871 BeijingChina Key Laboratory of Tropical Biological Resources of Ministry of Education School of Pharmaceutical SciencesHainan University570228 HaikouChina Key Laboratory of Animal Models and Human Disease Mechanisms of the Chinese Academy of Sciences&Yunnan Province KIZ/CUHK Joint Laboratory of Bioresources and Molecular Research in Common DiseasesKunming Institute of ZoologyChinese Academy of Sciences650204 KunmingYunnanChina National Institute on Drug Dependence and Beijing Key Laboratory of Drug Dependence Peking UniversityBeijing 100191China Institute of Brain Science and Brain-inspired Research Shandong First Medical University&Shandong Academy of Medical Sciences250117 JinanShandongChina Department of Neurology Shandong Provincial Hospital Affiliated to Shandong First Medical UniversityJinanShandongChina School of Public Health Peking University100191 BeijingChina

The coronavirus disease 2019(COVID-19)pandemic has been looming globally for three years,yet the diagnostic and treatment methods for COVID-19 are still undergoing extensive exploration,which holds paramount importance in mitigating future epidemics.Host non-coding RNAs(ncRNAs)display aberrations in the context of COVID-19.Specifically,microRNAs(miRNAs),long non-coding RNAs(lncRNAs),and circular RNAs(circRNAs)exhibit a close association with viral infection and disease progression.In this comprehensive review,an overview was presented of the expression profiles of host ncRNAs following SARS-CoV-2 invasion and of the potential functions in COVID-19 development,encompassing viral invasion,replication,immune response,and multiorgan deficits which include respiratory system,cardiac system,central nervous system,peripheral nervous system as well as long COVID.Furthermore,we provide an overview of several promising host ncRNA biomarkers for diverse clinical scenarios related to COVID-19,such as stratification biomarkers,prognostic biomarkers,and predictive biomarkers for treatment response.In addition,we also discuss the therapeutic potential of ncRNAs for COVID-19,presenting ncRNA-based strategies to facilitate the development of novel treatments.Through an in-depth analysis of the interplay between ncRNA and COVID-19 combined with our bioinformatic analysis,we hope to offer valuable insights into the stratification,prognosis,and treatment of COVID-19.

关键词： invasion therapeutic infection

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The role of intraoperative neurophysiological monitoring in intramedullary spinal cord tumor surgery

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Chinese Neurosurgical Journal 2024年第1期10卷 57-66页

作者： kai liu Chengyuan Ma Dapeng Li Haisong Li Xuechao Dong Bo liu ying Yu Yuxiang Fan Hongmei Song Department of Neurosurgery Bethune First Hospital of Jilin UniversityChangchunJilinChina

Intramedullary tumors are a class of central nervous system tumors with an incidence of 2 to 4%.As they are located very deep and frequently cause postoperative neurological complications,surgical resection is difficult.In recent years,many surgeons have performed electrophysiological monitoring to effectively reduce the occurrence of post-operative neurological complications.Modern electrophysiological monitoring technology has advanced considerably,leading to the development of many monitoring methods,such as SSEPs,MEPs,DCM,and EMG,to monitor intramedullary tumors.However,electrophysiological monitoring in tumor resection is still being studied.In this article,we discussed the different monitoring methods and their role in monitoring intramedullary tumors by reviewing previous studies.Intratumorally tumors need to be monitored for a summary of the condition of the patient.Only by using various monitoring methods flexibly and through clear communication between surgeons and neurophysiological experts can good decisions be made during surgery and positive surgical results be achieved.

关键词： Intramedullary spinal cord tumor Intraoperative neurophysiological monitoring D-wave

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Lanthanide-based microlasers:Synthesis,structures,and biomedical applications

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Nano Research 2024年第1期17卷 97-111页

作者： Qian Zhang Yawei liu kai liu Hongjie Zhang Engineering Research Center of Advanced Rare Earth Materials(Ministry of Education) Department of ChemistryTsinghua UniversityBeijing 100084China State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Xiangfu Laboratory Jiaxing 314102China

The large size of lasers limits their applications in confined spaces,such as in biosensing and in vivo brain tissue imaging.In this regard,micron-sized lasers have been developed.They exhibit great potential for biological detecting,remote sensing,and depth tracking due to their small sizes,sensitive properties of their spectral fingerprints,and flexible positional modulation in the microenvironment.Lanthanide-based luminescent materials that possess long excited-state lifetime,narrow emission bandwidth,and upconversion behaviors are promising as gain mediums for novel microlasers.In addition,lanthanide-based microlasers could be generated under natural ambient conditions with pumped or continuous light sources,which significantly promotes the practical applications of microlasers.Recent progress in the design,synthesis,and biomedical applications of lanthanide-based microlasers has been outlined in this review.Lanthanide ions doped and upconverted lanthanide-based microlasers are highlighted,which exhibit advantageous structures,miniaturized dimensions,and high lasing performance.The applications of lanthanide-based microlasers are further discussed,the upconverted microlasers show great advantages for biological applications owing to their tunable excitation and emission characteristics and excellent environmental stability.Moreover,perspectives and challenges in the field of lanthanide-based microlasers are presented.

关键词： microlasers lanthanide-based luminescent materials upconversion nanoparticles biological applications

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Study on macro and micro shear strength of continuously graded and gap-graded sand

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Particuology 2024年第3期86卷 101-116页

作者： Peiran Zhao Songyu liu kai Wu School of Transportation Southeast UniversityNanjing210096China

The particle gradation of sand has a significant influence on its shear strength,yet the similarities and differences between the effects of continuous and gap grading have yet to be fully explored.In this study,the discrete element method(DEM)was used to simulate biaxial tests on granular samples that were both continuously graded and gap-graded.The macroscopic analysis revealed that the shear strength of continuously graded sands increases initially and then decreases as the uniformity of particle size distribution decreases.On the other hand,the lack of medium particles in gap-graded sands amplifies the difference in particle size between coarse and fine particles,leading to a decrease in shear strength.Microscopically,both continuous and gap gradings affect the internal packing structure of the particle assembly,which consequently affects particle stress distributions,contact forces,coordination numbers,stress-induced anisotropies,and contact force networks,thus having an impact on the macroscopic shear strength.The global uniformity of particle size distribution was unidirectionally affected by continuous grading,while gap grading had a locally bidirectional influence.These findings provide a better understanding of the effects of particle grading on the macroscopic shear strength of sands.

关键词： Biaxial test Shear strength Particle gradation Discrete element method Micromechanics

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Multi-stimuli-responsive aggregation-induced emission copper iodide cluster

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Science China Chemistry 2024年第4期67卷 1193-1197页

作者： Bo Li Yuan-Yuan liu Peng Luo Ye-Ru liu ying-Jun Chen kai Li Shuang-Quan Zang College of Chemistry and Pharmacy Engineering Nanyang Normal UniversityNanyang 473061China Green Catalysis Center and College of Chemistry Zhengzhou UniversityZhengzhou 450001China

Stimuli-responsive luminescent materials have attracted significant attention in the development of smart photoactive materials for both fundamental research and technological applications.In this work,a new copper iodide cluster(1)with aggregationinduced emission(AIE)characteristic,was obtained combining Cu_(4)I_(4) core with rhodamine B derivative ligand.1 has reversible and distinct multi-stimuli-responsive luminescence for external temperature,volatile organic compound,and mechanical force.Significantly,1 exhibited unusual large blue shift(84 nm)after being ground,which originated from the change of intermolecular interactions.Moreover,1 exhibits high oxygen quenching efficiency for 82.2% at 1 bar.Mechanistic studies showed that the multi-stimuli-responsive luminescence properties of 1 can be attributed to the regulation of cluster-centered luminescence process,metal-to-ligand charge transfer process,halide-to-metal charge transfer luminescence process and aggregationinduced barrier to oxygen process.This work not only reports an AIE copper iodide cluster,but also provides a new strategy to develop multi-stimuli-responsive luminescence materials.

关键词： copper iodide cluster aggregation-induced emission multi-stimuli-response

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