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Neural Stem Cell Competition

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Neuroscience Bulletin 2024年第2期40卷 277-279页

作者： Yanan Li Jie He State Key Laboratory of Neuroscience Institute of NeuroscienceCenter for Excellence in Brain Science and Intelligence TechnologyChinese Academy of SciencesShanghai 200031China University of Chinese Academy of Sciences Beijing 100049China

Cell competition is an adaptive surveillance mechanism to ensure the robustness of developmental outputs,maintain tissue integrity,and regulate tumor progression in multicellular organisms,which is highly conserved from invertebrates to vertebrates[1].At the cellular level,cell competition represents a non-cell-autonomous process in that cells can sense the fitness of their neighbors through cellular interactions,thereby eliminating low-fitness cells and expanding high-fitness counterparts,however,cells develop normally in homogenous populations.

关键词： thereby maintain eliminating

Regulated polarization degree of upconversion luminescence and multiple anti-counterfeit applications

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Rare Metals 2024年第5期43卷 2172-2183页

作者： Dong-Ping Wen Ping Chen Yi Liang Xiao-Ming Mo Cao-Feng Pan center On Nanoenergy Research Guangxi Key Laboratory for Relativistic AstrophysicsSchool of Physical Science and TechnologyGuangxi UniversityNanning 530004China Key Laboratory of Micronano Energy and Sensor CAS Center for Excellence in NanoscienceBeijing Institute of Nanoenergy and NanosystemsChinese Academy of SciencesBeijing 100140China

Polarization upconversion luminescence(PUCL)of lanthanide ions(Ln^(3+))has been widely used in single particle tracking,microfluidics detection,three-dimensional displays,and so ***,no effective strategy has been developed for modulating *** we report a strategy to regulate PUCL in Ho^(3+)-doped NaYF4single nanorods based on the number of upconversion *** constructing a multiphoton upconversion system for Ho^(3+),we regulate the degree of polarization(DOP)of PUCL from 0.590 for two-photon luminescence to 0.929 for three-photon upconversion luminescence(UCL).Furthermore,our strategy is verified from cross-relaxation between Ho^(3+)and Yb^(3+),excitation wavelength,excitation power density,and local site *** this regulation strategy of PUCL has also been achieved in Tm^(3+),with the DOP ranging from 0.233 for two-photon luminescence to 0.925 for four-photon UCL Besides,multi-dimensional anti-counterfeiting display has been explored with *** work provides an effective strategy for regulating PUCL and also provides more opportunities for the development of polarization display optical encoding,anti-counterfeiting,and integrated optical devices.

关键词： Polarization upconversion luminescence Degree of polarization Population density of excited state Number of upconversion photons Polarization anti-counterfeitingdisplay

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A convolutional neural network to detect possible hidden data in spatial domain images

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Cybersecurity 2024年第1期7卷 37-52页

作者： Jean De La Croix Ntivuguruzwa Tohari Ahmad Department of Informatics Institut Teknologi Sepuluh Nopember(ITS)Kampus ITS Keputih SukoliloSurabaya60111Indonesia African center of excellence in the Internet of Things College of Science and TechnologyUniversity of Rwanda3900KigaliRwanda

Hiding secret data in digital multimedia has been essential to protect the ***,attackers with a steganalysis technique may break *** steganalysis methods have good results with conventional Machine Learning(ML)techniques;however,the introduction of Convolutional Neural Network(CNN),a deep learning paradigm,achieved better performance over the previously proposed ML-based *** the existing CNN-based approaches yield good results,they present performance issues in classification accuracy and stability in the network training *** research proposes a new method with a CNN architecture to improve the hidden data detection accuracy and the training phase stability in spatial domain *** proposed method comprises three phases:pre-processing,feature extraction,and ***,in the pre-processing phase,we use spatial rich model filters to enhance the noise within images altered by data hiding;secondly,in the feature extraction phase,we use two-dimensional depthwise separable convolutions to improve the signal-to-noise and regular convolutions to model local features;and finally,in the classification,we use multi-scale average pooling for local features aggregation and representability enhancement regardless of the input size variation,followed by three fully connected layers to form the final feature maps that we transform into class probabilities using the softmax *** results identify an improvement in the accuracy of the considered recent scheme ranging between 4.6 and 10.2%with reduced training time up to 30.81%.

关键词： Information security Spatial domain steganalysis Deep learning Convolutional neural network Infrastructure

Seasonal Characteristics of Forecasting Uncertainties in Surface PM_(2.5)Concentration Associated with Forecast Lead Time over the Beijing-Tianjin-Hebei Region

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Advances in Atmospheric Sciences 2024年第5期41卷 801-816页

作者： Qiuyan DU Chun ZHAO Jiawang FENG Zining YANG Jiamin XU Jun GU Mingshuai ZHANG Mingyue XU Shengfu LIN Deep Space Exploration Laboratory/School of Earth and Space Sciences University of Science and Technology of ChinaHefei 230026China CAS center for excellence in Comparative Planetology University of Science and Technology of ChinaHefei 230026China

Forecasting uncertainties among meteorological fields have long been recognized as the main limitation on the accuracy and predictability of air quality ***,the particular impact of meteorological forecasting uncertainties on air quality forecasts specific to different seasons is still not well *** this study,a series of forecasts with different forecast lead times for January,April,July,and October of 2018 are conducted over the Beijing-Tianjin-Hebei(BTH)region and the impacts of meteorological forecasting uncertainties on surface PM_(2.5)concentration forecasts with each lead time are *** increased lead time,the forecasted PM_(2.5)concentrations significantly change and demonstrate obvious seasonal *** general,the forecasting uncertainties in monthly mean surface PM_(2.5)concentrations in the BTH region due to lead time are the largest(80%)in spring,followed by autumn(~50%),summer(~40%),and winter(20%).In winter,the forecasting uncertainties in total surface PM_(2.5)mass due to lead time are mainly due to the uncertainties in PBL heights and hence the PBL mixing of anthropogenic primary *** spring,the forecasting uncertainties are mainly from the impacts of lead time on lower-tropospheric northwesterly winds,thereby further enhancing the condensation production of anthropogenic secondary particles by the long-range transport of natural *** summer,the forecasting uncertainties result mainly from the decrease in dry and wet deposition rates,which are associated with the reduction of near-surface wind speed and precipitation *** autumn,the forecasting uncertainties arise mainly from the change in the transport of remote natural dust and anthropogenic particles,which is associated with changes in the large-scale circulation.

关键词： PM_(2.5) forecasting uncertainties forecast lead time meteorological fields Beijing-Tianjin-Hebei region

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Functional characterization of Bmcap in uric acid metabolism in the silkworm

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Insect Science 2024年第1期31卷 147-156页

作者： Linmeng Tang Dehong Yang Zhiwei Liu Yaohui Wang Xu Yang Yujia Liu Dongbin Chen Zheng Tang Yongping Huang Key Laboratory of Insect Developmental and Evolutionary Biology Center for Excellence in Molecular Plant SciencesShanghai Institute of Plant Physiology and EcologyChinese Academy of SciencesShanghaiChina CAS center for excellence in Biotic Interactions University of Chinese Academy of SciencesBeijingChina Central Research Institute Shanghai Pharmaceuticals Holding Co.Ltd.ShanghaiChina Departments of Neonatology International Peace Maternity and Child Health Hospital of China Welfare InstitutionSchool of MedicineShanghai Jiao Tong UniversityShanghaiChina

After a millennium of domestication,numerous silkworm mutants have emerged that exhibit transparent epidermis,which is caused by abnormally low levels of uric *** identified the Bombyx mori gene Bmcap(BMSK0003832)as the homolog of cappuccino,a subunit of the biogenesis of lysosome-related organelles complex-1(BLOC-1)that has been extensively characterized in human,mouse,and insect species,by analyzing the amino acid sequences of putative purine metabolism *** the clustered regularly interspaced palindromic repeats(CRISPR)/CRISPR-associated protein 9 system,we disrupted Bmcap,resulting in decreased uric acid levels in the silkworm epidermis and a translucent skin *** the Bmcap mutant,the purine metabolism,nitrogen metabolism,pyrimidine metabolism,and membrane system were altered compared to the wild *** of lysosome-related organelle complex genes play a role in the pigmentation and biogenesis of lysosome-related organelles(LROs)in platelets,melanocytes,and *** exhibit unique morphologies and functions in various tissues and *** of the Bmcap mutant will enhance our understanding of the uric acid metabolic pathway in silkworms,and this mutant offers a valuable silkworm model for LRO studies.

关键词： BLOC-1 subunit Bombyx mori cappuccino translucent mutation uric acid

Modern phenomics to empower holistic crop science, agronomy, and breeding research

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Journal of Genetics and Genomics 2024年第8期51卷 790-800页

作者： Ni Jiang Xin-Guang Zhu Institute of Genetics and Developmental Biology Chinese Academy of SciencesBeijing 100101China center of excellence for Molecular Plant Sciences Chinese Academy of SciencesShanghai 200032China

Crop phenomics enables the collection of diverse plant traits for a large number of samples along different time scales,representing a greater data collection throughput compared with traditional *** modern crop phenomics use different sensors to collect reflective,emitted,and fluorescence signals,etc.,from plant organs at different spatial and temporal *** multi-modal,high-dimensional data not only accelerates basic research on crop physiology,genetics,and whole plant systems modeling,but also supports the optimization of field agronomic practices,internal environments of plant factories,and ultimately crop *** challenges and opportunities facing the current crop phenomics research community include developing community consensus or standards for data collection,management,sharing,and processing,developing capabilities to measure physiological parameters,and enabling farmers and breeders to effectively use phenomics in the field to directly support agricultural production.

关键词： Crop phenomics High-throughput phenotyping Traits Crop designer breeding Agronomy

A versatile model with three-dimensional triangular lattice for unconventional transport and various topological effects

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National Science Review 2024年第1期11卷 204-214页

作者： Jing-Yang You Gang Su Yuan Ping Feng Department of Physics National University of Singapore Kavli Institute for Theoretical Sciences and CAS Center for Excellence in Topological Quantum Computation University of Chinese Academy of Sciences Centre for Advanced 2D Materials National University of Singapore

The finite Berry curvature in topological materials can induce many subtle phenomena, such as the anomalous Hall effect(AHE), spin Hall effect(SHE), anomalous Nernst effect(ANE), non-linear Hall effect(NLHE) and bulk photovoltaic effects. To explore these novel physics as well as their connection and coupling, a precise and effective model should be developed. Here, we propose such a versatile model—a 3D triangular lattice with alternating hopping parameters, which can yield various topological phases,including kagome bands, triply degenerate fermions, double Weyl semimetals and so on. We reveal that this special lattice can present unconventional transport due to its unique topological surface states and the aforementioned topological phenomena, such as AHE, ANE, NLHE and the topological photocurrent effect. In addition, we also provide a number of material candidates that have been synthesized experimentally with this lattice, and discuss two materials, including a non-magnetic triangular system for SHE, NLHE and the shift current, and a ferromagnetic triangular lattice for AHE and ANE. Our work provides an excellent platform, including both the model and materials, for the study of Berry-curvature-related physics.

关键词： three-dimensional triangular lattice different topological phases various topological effects Berry curvature

An unprecedented synthesis of axially chiral biaryls by rearrangement and aromatization of carbocations with central-to-axial conversion of chirality

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Science China Chemistry 2024年第9期67卷 2998-3003页

作者： Qi Liu Xue-Dong Li Liang Cheng Li Liu Beijing National Laboratory for Molecular Sciences (BNLMS) CAS Key Laboratory of Molecular Recognition and Function CAS Research/Education Center for Excellence in Molecular Sciences Institute of Chemistry Chinese Academy of Sciences University of Chinese Academy of Sciences

The central-to-axial chirality conversion represents a fascinating class of chemical processes consisting of the destruction of stereogenic centers and the simultaneous installation of axial chiral elements, which provides efficient methods for the preparation of axially chiral compounds. However, developing catalytic asymmetric approaches for constructing these central chirality precursors and the efficient central-to-axial chirality conversion remains a challenge due to the requirement of aromatization or elimination process. In this work, we have developed an unprecedented enantioselective intramolecular FriedelCrafts alkylation with unactivated-ketone carbonyls from which a chiral tertiary alcohol was generated with high efficiency and excellent enantioselectivity. In addition, the central-to-axial chirality conversion strategy has been successfully applied to the synthesis of enantioenriched biaryls via a less-explored carbocation-initiated rearrangement and aromatization under the promotion of Lewis acid. This methodology provided a straightforward and sustainable access to a broad range of biaryl-2-carboxylic acid and in excellent yields(up to 92%) and excellent central-to-axial chirality conversion(up to 99% conversion percentage). This work could be a great model for developing new methods for synthesizing axially chiral biaryls and a general protocol for the rearrangement and aromatization of carbocations for further functionalization.

关键词： brønsted acid catalysis desymmetrization phosphoric acid axially chiral biaryls central-to-axial conversion

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Context Processing in Contextual and Cued Fear Extinction

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Neuroscience Bulletin 2024年第6期40卷 835-839页

作者： Yimu Zhang Chun Xu Yu Gu State Key Laboratory of Medical Neurobiology and MOE Frontiers center for Brain Science Institutes of Brain ScienceFudan UniversityShanghai200032China Institute of Neuroscience State Key Laboratory of NeuroscienceCenter for Excellence in Brain Science and Intelligence TechnologyChinese Academy of SciencesShanghai200031China

Anxiety disorders such as post-traumatic stress disorder(PTSD)are prevalent mental disorders that disturb millions *** disorders often manifest as excessive fear,anxiety,and distress,significantly impacting daily *** fear extinction paradigms in animals were established decades ago and have been widely used in research,providing a scientific basis for exposure therapies for anxiety disorders in humans.

关键词： distress disorders traumatic