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First Digit Distributions of Gamma-Ray Bursts

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Research in Astronomy and Astrophysics 2024年第5期24卷 70-75页

作者： Hou-Yu Lai Jun-jie wei Purple Mountain Observatory Chinese Academy of SciencesNanjing 210023China School of Astronomy and Space Sciences University of Science and Technology of ChinaHefei 230026China

The occurrence of the first significant digits from real world sources is usually not equally distributed,but is consistent with a logarithmic distribution instead,known as Benford’s law.In this work,we perform a comprehensive investigation on the first digit distributions of the duration,fluence,and energy flux of gamma-ray bursts (GRBs) for the first time.For a complete GRB sample detected by the Fermi satellite,we find that the first digits of the duration and fluence adhere to Benford’s law.However,the energy flux shows a significant departure from this law,which may be due to the fact that a considerable part of the energy flux measurements is restricted by lack of spectral information.Based on the conventional duration classification scheme,we also check if the durations and fluences of long and short GRBs (with duration T_(90)>2 s and T_(90)≤2 s,respectively) obey Benford’s law.We find that the fluences of both long and short GRBs still agree with the Benford distribution,but their durations do not follow Benford’s law.Our results hint that the long–short GRB classification scheme does not directly represent the intrinsic physical classification scheme.

关键词： (stars:)gamma-ray burst general-methods statistical-astronomical databases miscellaneous

A discussion of fatigue properties of notched specimens subjected to prestressing treatment machined from FGH4097

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Chinese Journal of Aeronautics 2024年第4期37卷 508-523页

作者： Rongxi shi Dasheng wei Le HAN Shun YANG School of Energy and Power Engineering Beihang UniversityBeijing 100191China Jiangxi Research Institute Beihang UniversityNanchang 330096China Research Institute of Aero-Engine Beihang UniversityBeijing 100191China

Experimental and numerical investigations were performed to reveal the effect of prestress on the fatigue properties of FGH4097 so as to quantitatively evaluate the overspeed benefit of the disc of aeroengine. A corresponding experiment was performed to examine the effect of prestress on the fatigue life of FGH97. A complete model describing the fatigue properties of the prestressed notch specimen was proposed. After the modification of mean stress, stress gradient and prestressing treatment, the model is finally verified by fatigue test of presstressed notch specimens machined from FGH4097 with satisfactory accuracy and good engineering applicability. The new model highlights that for the variable fatigue loads, the introduction of appropriate prestress is expected to benefit to the notch specimens and certainly to the disc of aeroengine regards of their fatigue properties. Both the calculation method of fatigue life parameters and the prestress correction model are proved to have good prediction accuracy.

关键词： Turbine blisk Overspeed test Prestress Fatigue life prediction FGH4097

Geochronological and geochemical constraints on the petrogenesis and geodynamic process of Hemler,Vlinder,and Il'ichev seamount lavas in NW Pacific

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Science China Earth Sciences 2024年第6期67卷 1856-1871页

作者： Xun wei Yan ZHANG Xuefa shi Hui ZHANG Key Laboratory of Marine Geology and Metallogeny First Institute of OceanographyMinistry of Natural ResourcesQingdao 266061China Laboratory for Marine Geology Qingdao Marine Science and Technology CenterQingdao 266237China Shandong Key Laboratory of Deep Sea Mineral Resources Development(Preparatory) Qingdao 266061China

Oceanic intraplate volcanoes with linear age progressions are usually accepted to be derived from melting of an upwelling mantle plume.Several seamount groups in NW Pacific,however,show complex age-distance relationships that are difficult to explain using the classic“mantle plume hypothesis”,and thus their origins are controversial.In this study,we present ^(40)Ar-^(39)Ar age,geochemical,and Sr-Nd-Pb-Hf isotopic data of lavas from Hemler,Vlinder,and Il’ichev seamounts in NW Pacific,to elucidate their petrogenesis and geodynamic process.The lavas from Hemler,Vlinder,and Il’ichev seamounts are classified as alkali basalt,basanite/nephelinite,and trachyte.Lavas with Mg O>8 wt.%exhibit high contents of CaO,FeO^(T),and TiO_(2),similar to the composition of melts formed from reaction between carbonated eclogite-derived melts and fertile peridotite.These lavas have elevated Zr/Hf ratios(40.6-45.2)and negative Zr and Hf anomalies,indicating the presence of a carbonate component in the mantle source.They are enriched in incompatible trace elements and have enriched mantle 1(EM1)-like SrNd-Pb-Hf isotopic compositions.The isotopic compositions of Vlinder,Il’ichev basanite,and Hemler lavas in this study are similar to the Rarotonga hotspot.Although occurring at the same seamount,the Il’ichev alkali basalts display more depleted SrNd-Hf isotopic compositions compared to Il’ichev basanite.According to plate tectonic reconstruction results,the ages of Hemler(100.1 Ma),Vlinder pre-(100.2 Ma)and post-shield(87.5 Ma),and Il’ichev(56.4 Ma)lavas clearly deviate from the Macdonald,Arago,Rarotonga,and Samoa hotspot tracks,indicating that they cannot directly originate from mantle plumes.We propose that in the mid-Cretaceous,when the Pacific plate passed over Rarotonga hotspot,melting of Rarotonga plume formed the Vlinder(main-shield stage),Pako,and Ioah seamounts.The Rarotonga(and possibly Samoa)plume materials would have been dispersed into the surrounding asthenosphere by mantle convection.These diffuse plume materials would underg

关键词： Mantle plume Magellan seamount trail Carbonated mantle component Hotspot Lithosphere extension

Al-doped ZnO/WO_(3) heterostructure films prepared by magnetron sputtering for isopropanol sensors

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Rare Metals 2024年第1期43卷 247-256页

作者： wei-Xiang Gao Xue-Ting Chang Xiao-jie Zhu Jun-Feng Li Ying-Chang Jiang Dong-Sheng Wang Chuan-Xiao Yang shi-Bin Sun College of Logistics Engineering Shanghai Maritime UniversityShanghai 201306China College of Ocean Science and Engineering Shanghai Maritime UniversityShanghai 201306China Institute of Logistics Science and Engineering Shanghai Maritime UniversityShanghai 201306China

Metal oxide semiconductors(MOSs) are ideal sensing materials for detecting volatile organic compounds due to their low cost, diversity, high stability, and ease of production. However, it remains a grand challenge to develop the MOSs-based gas sensors for sensing isopropanol with desired performance via a simple, effective,and controllable method. Herein, we reported the preparation of the Al-doped Zn O(AZO)/WO_(3) heterostructure films by directly depositing the AZO coating onto the WO_(3) coating using a strategy of magnetron sputtering. The AZO/WO_(3) heterostructure films were constructed by numbers of irregular nanoparticles that were interconnected with each other. The AZO/WO_(3) heterostructure films-based gas sensors exhibited excellent isopropanolsensing performance with high response, promising selectivity, low detection limit, fast response rate, wide detection range, and ideal reproducibility. The promising isopropanol-sensing performance of the AZO/WO_(3) heterostructure films arises mainly from their high uniformity, unique microstructures with high surface roughness,and the construction of the heterostructure between the AZO and WO_(3) coatings. This work provides a versatile approach to prepare the MOSs-based heterostructure films for assembling the gas sensors.

关键词： Metal oxide semiconductors Gas sensors Aldoped ZnO/WO_(3) Heterostructure films Isopropanol Magnetron sputtering

Analysis of large datasets for identifying molecular targets in intestinal polyps and metabolic disorders

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BIOCELL 2024年第3期48卷 415-429页

作者： SHAN OU YUN XU QINGLAN LIU TIANWEN YANG wei CHEN XIU YUAN XIN ZUO PENG shi jie YAO Department of Gastroenterology The First Affiliated Hospital of Chongqing Medical and Pharmaceutical CollegeChongqingChina

Background:The interrelation between intestinal polyps,metabolic syndrome(MetS),and colorectal cancer(CRC)is a critical area of study.This research focuses on pinpointing potential molecular targets to understand the link between intestinal polyp formation,metabolic irregularities,and CRC progression.Methods:We examined clinical samples from patients with intestinal polyps coexisting with MetS and compared them with samples from patients with standard intestinal polyps.Transcriptome sequencing and public database analysis were employed to identify significant pathways and genes.These targets were then validated through immunohistochemistry(IHC).Following the RNA interference of key target expression,a series of experiments,including the cell counting kit-8 assay,colony formation,wound healing,and Transwell assays,were conducted.Results:Comparative analysis revealed 75 up-regulated and 61 down-regulated differentially expressed genes(DEGs)in the MetS polyp group vs.the control.Kyoto encyclopedia of genes and genomes(KEGG)pathway enrichment suggested these DEGs were primarily associated with cell cycle and mitosis.Integration with comparative toxicogenomics database(CTD)and the cancer genome atlas(TCGA)databases highlighted 44 key CRC-related genes.Protein interaction networks indicated connections of purkinje cell protein 4(PCP4),olfactomedin 1(OLFM1),fibronectin 1(FN1),and transforming growth factor beta 3(TGF-β3)with the mitogen-activated protein kinase(MAPK)pathway.Tumor correlation studies suggested higher risk associations with FN1,PCP4,and TGF-β3,while OLFM1 was identified as a lower risk gene.Immunohistochemical analysis revealed a decrease in OLFM1 in MetS-associated intestinal polyps.Upon interference with OLFM1 in polyp epithelial cells,there was a significant enhancement in cell proliferation,colony formation,and cell migration and invasion capabilities.Conclusion:Our study highlights a significant decrease in OLFM1 expression in MetS-associated intestinal polyps.And,this reduction in OLFM1 is associate

关键词： Colorectal cancer Metabolic syndrome Intestinal polyp OLFM1 Exosome

A quantum circuit design of AES requiring fewer quantum qubits and gate operations

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Frontiers of physics 2022年第4期17卷 99-105页

作者： Ze-Guo Wang shi-jie wei Gui-Lu Long State Key Laboratory of Low-Dimensional Quantum Physics and Department of Physics Tsinghua UniversityBeijing 100084China Beijing Academy of Quantum Information Sciences Beijing 100193China Beijing National Research Center for Information Science and Technology and School of Information Tsinghua University Beijing 100084China Frontier Science Center for Quantum Information Beijing 100084China

Advanced Encryption Standard(AES)is one of the most widely used block ciphers nowadays,and has been established as an encryption standard in 2001.Here we design AES-128 and the sample-AES(S-AES)quantum circuits for deciphering.In the quantum circuit of AES-128,we perform an affine transformation for the SubBytes part to solve the problem that the initial state of the output qubits in SubBytes is not the|0⟩⊗8 state.After that,we are able to encode the new round sub-key on the qubits encoding the previous round sub-key,and this improvement reduces the number of qubits used by 224 compared with Langenberg et al.’s implementation.For S-AES,a complete quantum circuit is presented with only 48 qubits,which is already within the reach of existing noisy intermediate-scale quantum computers.

关键词： AES S-AES quantum circuit quantum attack

The genome-wide meiotic recombination landscape in ciliates and its implications for crossover regulation and genome evolution

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Journal of Genetics and Genomics 2024年第3期51卷 302-312页

作者： Lu Fu Chen Gu Kazufumi Mochizuki jie Xiong wei Miao Guangying Wang Key Laboratory of Aquatic Biodiversity and Conservation Institute of HydrobiologyChinese Academy of SciencesWuhanHubei 430072China University of Chinese Academy of Sciences Beijing 100049China Institute of Human Genetics(IGH) CNRSUniversity of Montpellier34396 MontpellierFrance Key Laboratory of Breeding Biotechnology and Sustainable Aquaculture Chinese Academy of SciencesWuhanHubei 430072China Key Laboratory of Lake and Watershed Science for Water Security Chinese Academy of SciencesNanjingJiangsu 210008China

Meiotic recombination is essential for sexual reproduction and its regulation has been extensively studied in many taxa.However,genome-wide recombination landscape has not been reported in ciliates and it remains unknown how it is affected by the unique features of ciliates:the synaptonemal complex(SC)-independent meiosis and the nuclear dimorphism.Here,we show the recombination landscape in the model ciliate Tetrahymena thermophila by analyzing single-nucleotide polymorphism datasets from 38 hybrid progeny.We detect 1021 crossover(CO)events(35.8 per meiosis),corresponding to an overall CO rate of 9.9 cM/Mb.However,gene conversion by non-crossover is rare(1.03 per meiosis)and not biased towards G or C alleles.Consistent with the reported roles of SC in CO interference,we find no obvious sign of CO interference.CO tends to occur within germ-soma common genomic regions and many of the 44 identified CO hotspots localize at the centromeric or subtelomeric regions.Gene ontology analyses show that CO hotspots are strongly associated with genes responding to environmental changes.We discuss these results with respect to how nuclear dimorphism has potentially driven the formation of the observed recombination landscape to facilitate environmental adaptation and the sharing of machinery among meiotic and somatic recombination.

关键词： Meiotic recombination Hotspot Crossover interference Adaptive evolution

A bilateral heterogeneous graph model for interpretable job recommendation considering both reciprocity and competition

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Frontiers of Engineering Management 2024年第1期11卷 128-142页

作者： Xiaowei shi Qiang wei Guoqing CHEN School of Economics and Management Tsinghua UniversityBeijing 100084China

Amidst the inefficiencies of traditional job-seeking approaches in the recruitment ecosystem, the importance of automated job recommendation systems has been magnified. However, existing models optimized to maximize user clicks for general product recommendations prove inept in addressing the unique challenges of job recommendation, namely reciprocity and competition. Moreover, sparse data on online recruitment platforms can further negatively impact the performance of existing job recommendation algorithms. To counteract these limitations, we propose a bilateral heterogeneous graph-based competition iteration model. This model comprises three integral components: 1) two bilateral heterogeneous graphs for capturing multi-source information from people and jobs and alleviating data sparsity, 2) fusion strategies for synthesizing attributes and preferences to produce mutually beneficial job matches, and 3) a competition-enhancing strategy for dispersing competition realized through a two-stage optimization algorithm. Augmented by granular attention mechanisms for enhanced interpretability, the model’s efficacy, competition dispersion, and interpretability are validated through rigorous empirical evaluations on a real-world recruitment platform.

关键词： job recommendation competition reciprocity interpretability

Evaluation of dry eye disease symptomatology and mental health status among patients with different COVID-19 statuses

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International Journal of Ophthalmology(English edition) 2024年第5期17卷 822-830页

作者： Fang Ruan Wen-Jun Kong Qian Fan Hong-wei Dong wei Zhang Wen-Bin wei Ying jie Department of Ophthalmology Beijing You’an HospitalCapital Medical UniversityBeijing Infectious Eye Disease Diagnosis and Treatment CenterBeijing 100069China Beijing Tongren Eye Center Beijing Tongren HospitalCapital Medical UniversityBeijing Institute of OphthalmologyBeijing Ophthalmology and Visual Sciences Key LabBeijing 100730China Tianjin Eye Hospital Tianjin Key Lab of Ophthalmology and Visual ScienceTianjin Eye InstituteNankai University Affiliated Eye HospitalNankai University Eye InstituteNankai UniversityClinical College of OphthalmologyTianjin Medical UniversityTianjin 300020China

AIM:To evaluate dry eye disease(DED)symptomatology and mental health status in different COVID-19 patients.METHODS:A cross-sectional observational design was used.Totally 123 eligible adults(46.34%of men,age range,18-59y)with COVID-19 included in the study from August to November,2022.Ocular Surface Disease Index(OSDI),Five-item Dry Eye Questionnaire(DEQ-5),Hospital Anxiety and Depression Scale(HADS),and Pittsburgh Sleep Quality Index(PSQI)were used in this study.RESULTS:OSDI scores were 6.82(1.25,15.91)in asymptomatic carriers,7.35(2.50,18.38)in mild cases,and 16.67(4.43,28.04)in recurrent cases,with 30.00%,35.56%,and 57.89%,respectively evaluated as having DED symptoms(χ2=7.049,P=0.029).DEQ-5 score varied from 2.00(0,6.00)in asymptomatic carriers,3.00(0,8.00)in mild cases,and 8.00(5.00,10.00)in recurrent cases,with 27.50%,33.33%,and 55.26%,respectively assessed as having DED symptoms(χ2=8.532,P=0.014).The prevalence of clinical anxiety(50.00%)and depression(47.37%)symptoms were also significantly higher in patients with recurrent infection(χ2=24.541,P<0.001;χ2=30.871,P<0.001).Recurrent infection was a risk factor for high OSDI scores[odds ratio,2.562;95%confidence interval(CI),1.631-7.979;P=0.033]and DEQ-5 scores(odds ratio,3.353;95%CI,1.038-8.834;P=0.043),whereas having a fixed occupation was a protective factor for OSDI scores(odds ratio,0.088;95%CI,0.022-0.360;P=0.001)and DEQ-5 scores(odds ratio,0.126;95%CI,0.039-0.405;P=0.001).CONCLUSION:Patients with recurrent COVID-19 have more severe symptoms of DED,anxiety,and depression.

关键词： COVID-19 dry eye disease recurrent infection mental health