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PRSS50-mediated inhibition of MKP3/ERK signaling is crucial for meiotic progression and sperm quality

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Zoological Research 2024年第5期45卷 1037-1047页

作者： chun-Xue Niu Jia-Wei li Xiao-li li lin-lin Zhang Yan Lang Zhen-Bo Song chun-Lei Yu Xiao-Guang Yang Hai-Feng Zhao Jia-ling Sun li-Hua zheng Xue Wang Ying Sun Xiao-Hong Han Guan-Nan Wang Yong-li Bao National Engineering Laboratory for Druggable Gene and Protein Screening Northeast Normal UniversityChangchunJilin 130117China China International Joint Research Center for Human Stem Cell Bank Northeast Normal UniversityChangchunJilin 130117China Jilin Institute for Drug Control ChangchunJilin 130022China

Serine protease 50(PRSS50/TSP50)is highly expressed in *** study investigated its role in testicular development and ***,PRSS50 knockdown was observed to impair DNA synthesis in *** further explore this,we generated PRSS50 knockout(Prss50^(−/−))mice(Mus musculus),which exhibited abnormal spermatid nuclear compression and reduced male ***,dysplastic seminiferous tubules and decreased sex hormones were observed in 4-week-old Prss50^(−/−)mice,accompanied by meiotic progression defects and increased apoptosis of spermatogenic *** analysis indicated that PRSS50 deletion resulted in increased phosphorylation of extracellular signal-regulated protein kinases 1 and 2(ERK1/2)and elevated levels of MAP kinase phosphatase 3(MKP3),a specific ERK antagonist,potentially accounting for testicular dysplasia in adolescent Prss50−/−*** together,these findings suggest that PRSS50 plays an important role in testicular development and spermatogenesis,with the MKP3/ERK signaling pathway playing a significant role in this process.

关键词： PRSS50(TSP50) Meiotic progression Sperm quality MKP3 ERK

Precise immobilization of metal single atoms into a porphyrinic metal-organic framework for an efficient alkene hydrosilylation

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Nano Research 2024年第7期17卷 5914-5921页

作者： chun-Ying Chen Qi-Jie Mo Fu-Zhen li Hai-li Song li Zhang MOE Laboratory of Bioinorganic and Synthetic Chemistry Lehn Institute of Functional MaterialsSchool of ChemistrySun Yat-Sen UniversityGuangzhou 510006China

Alkene hydrosilylation is one of the most concise and atom-economical methods to synthesize organosilicon ***,we reported the precise immobilization of metal single atoms(M-SAs;M=Ru,Rh,Ir,Pd,Pt,and Au)into a porphyrinic metalorganic framework(MOF)of PCN-222(PCN=porous coordination network),and then applied the resultant MOF composites of M-SAs@PCN-222 to alkene *** solvent-free conditions,Pt-SAs@PCN-222 displayed an especially high catalytic efficiency with the turnover frequency up to 119 s−1 and the maximum turnover number of 906,250 at room *** and theoretical studies revealed that there existed strong interactions between Pt-SAs@PCN-222 and the substrates,which helped to condense the substrates in the cavities of the porous *** density functional theory calculations and molecular dynamics simulations disclosed that PCN-222 could transfer electrons to Pt-SAs to enhance the silane oxidative addition and drive the reaction to proceed smoothly via Chalk–Harrod pathway.

关键词： alkene hydrosilylation single atom catalysts metal-organic frameworks precision chemistry synergistic catalysis

lightweight Res-Connection Multi-Branch Network for Highly Accurate Crowd Counting and Localization

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Computers, Materials & Continua 2024年第5期79卷 2105-2122页

作者： Mingze li Diwen zheng Shuhua Lu College of Information and Cyber Security People’s Public Security University of ChinaBeijing102600China

Crowd counting is a promising hotspot of computer vision involving crowd intelligence analysis,achieving tremendous success recently with the development of deep ***,there have been stillmany challenges including crowd multi-scale variations and high network complexity,*** tackle these issues,a lightweight Resconnection multi-branch network(LRMBNet)for highly accurate crowd counting and localization is ***,using improved ShuffleNet V2 as the backbone,a lightweight shallow extractor has been designed by employing the channel compression mechanism to reduce enormously the number of network parameters.A light multi-branch structure with different expansion rate convolutions is demonstrated to extract multi-scale features and enlarged receptive fields,where the information transmission and fusion of diverse scale features is enhanced via residual *** addition,a compound loss function is introduced for training themethod to improve global context information *** proposed method is evaluated on the SHHA,SHHB,UCF-QNRF and UCF_CC_50 public *** accuracy is better than those of many advanced approaches,while the number of parameters is *** experimental results show that the proposed method achieves a good tradeoff between the complexity and accuracy of crowd counting,indicating a lightweight and high-precision method for crowd counting.

关键词： Crowd counting Res-connection multi-branch compound loss function

Using Improved Particle Swarm Optimization Algorithm for Location Problem of Drone Logistics Hub

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Computers, Materials & Continua 2024年第1期78卷 935-957页

作者： li zheng Gang Xu Wenbin Chen School of Mathematics and Computer Sciences Nanchang UniversityNanchang330031China

Drone logistics is a novel method of distribution that will become *** advantageous location of the logistics hub enables quicker customer deliveries and lower fuel consumption,resulting in cost savings for the company’s transportation *** firms must discern the ideal location for establishing a logistics hub,which is challenging due to the simplicity of existing models and the intricate delivery *** simulate the drone logistics environment,this study presents a new mathematical *** model not only retains the aspects of the current models,but also considers the degree of transportation difficulty from the logistics hub to the village,the capacity of drones for transportation,and the distribution of logistics hub ***,this paper proposes an improved particle swarm optimization(PSO)algorithm which is a diversity-based hybrid PSO(DHPSO)algorithm to solve this *** DHPSO,the Gaussian random walk can enhance global search in the model space,while the bubble-net attacking strategy can speed ***,Archimedes spiral strategy is employed to overcome the local optima trap in the model and improve the exploitation of the *** maintains a balance between exploration and exploitation while better defining the distribution of logistics hub locations Numerical experiments show that the newly proposed model always achieves better locations than the current *** DHPSO with other state-of-the-art intelligent algorithms,the efficiency of the scheme can be improved by 42.58%.This means that logistics companies can reduce distribution costs and consumers can enjoy a more enjoyable shopping experience by using DHPSO’s location *** the results show the location of the drone logistics hub is solved by DHPSO effectively.

关键词： Drone logistics location problem mathematical model diversity particle swarm optimization

Detection of Increasingγ-Ray Emissions from 4FGL J1718.5+4237 with Fermi-LAT

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Research in Astronomy and Astrophysics 2024年第8期24卷 169-174页

作者： Jiao zheng Pengfei Zhang li Zhang Department of Astronomy School of Physics and AstronomyKey Laboratory of Astroparticle Physics of Yunnan ProvinceYunnan UniversityKunming 650091China School of Physics and Engineering Technology Xingyi Normal University for NationalitiesXingyi 562400China

We report a gradual brighteningγ-ray source,4FGL J1718.5+4237,in 0.1-500.0 GeV,which may be associated with a blazar NVSS J171822+423948 with a redshift of~*** analyzed 15.25 yr ofγ-ray data recorded by the Large Area Telescope on board the Fermi Gamma-ray Space Telescope and detected significantγ-ray emissions in the direction of the blazar with a test statistic(TS)of~*** on timing analysis using a 1 yr time bin,we have observed a gradual brightening inγ-ray emissions from the *** our analysis,we categorize them into two states:Quiet(TS~0)and Loud(TS~226)states,with the distinction occurring in 2016 August(MJD57602.69).From the Quiet state to the brightest period(the last data point),theγ-ray flux in 0.1-500.0 GeV increased by more than 12-fold from<0.2×10^(-8)photons cm^(-1)s^(-1)to 2.6×10^(-8)photons cm^(-1)s^(-1).Additionally,we studied the spectral properties in detail for the Loud state and the overall *** no significant variation was detected,both exhibited a spectral indexΓof~*** origin of the brighteningγ-ray emissions from the target is not yet *** long-term multi-wavelength observations and studies will provide insight into the astrophysical mechanisms of the target.

关键词： galaxies active-blazars individual(4FGL J1718.5+4237)

Evolution of Diagenetic Fluid of the Dawsonite-Bearing Sandstone in the Jiyang Depression,Eastern China

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Journal of Ocean University of China 2024年第1期23卷 80-98页

作者： li Fulai MA Wenkuan ZHANG chun WANG Kaining National Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)Qingdao 266580China Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and TechnologyQingdao 266071China Shandong Geological Exploration Institute of China Chemical Geology and Mine Bureau Jinan 250013China

Based on the petrology,isotope geochemistry and fluid inclusions analysis,we established the evolutionary mode of the diagenetic fluid of dawsonite-bearing sandstone in the Jiyang ***-bearing sandstone is characterized by double injection of CO_(2)and oil-gas in the Jiyang Depression that have experienced a relatively complex diagenetic fluid evolution *** diagenetic sequence of secondary minerals involves secondary enlargement of quartz,kaolinite,first-stage calcite,dawsonite,second-stage calcite,ferrocalcite,dolomite and *** charging in the dawsonite-bearing sandstone occurred at around 2.6–0 *** CO_(2)charging event occurred during Dongying tectonism,forming the Pingfangwang CO_(2)gas reservoir,which provided an abundant carbon source for dawsonite *** and oxygen isotopic compositions of dawsonite demonstrate that CO_(2)forming the dawsonite was of an inorganic origin derived from the mantle,and that water mediating the proc-ess during dawsonite precipitation was sequestered brine with a fluid temperature of 82℃.The evolutionary sequence of the diagenetic fluid in the dawsonite-bearing sandstone was:alkaline syngenetic fluids,weak alkaline fluids during organic acid forma-tion,acidic fluids in the early stage of CO_(2)injection,alkaline fluids in the late stage of CO_(2)injection,and weak alkaline fluids during oil and gas *** mode indicates an increase in-HCO_(3)because of the CO_(2)injection,and the loss of Ca^(2+)and Mg^(2+)due to the precipitation of carbonate ***,the evolutionary mode of diagenetic fluids is in good agreement with high HCO_(3)^(-),low Ca^(2+)and low Mg^(2+)composition of the present formation water in the dawsonite-bearing sandstone.

关键词： evolution of diagenetic fluid dawsonite CO_(2)injection and hydrocarbon charging mineral diagenetic sequence iso-topic geochemistry fluid inclusions

Discovery of the choristodere Hyphalosaurus baitaigouensis from the Lower Cretaceous Jiufotang Formation of western liaoning,China and its paleobiogeographic significance

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Journal of Palaeogeography 2024年第3期13卷 547-562页

作者： li-Jun Zhang Shu-An Ji Hai-chun Zhang South China Sea Culture Museum Hainan Tropical Ocean UniversitySanya 572022Hainan ProvinceChina Key Laboratory of Stratigraphy and Paleontology Ministry of Natural ResourcesInstitute of GeologyChinese Academy of Geological SciencesBeijing 100037China State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology and Center for Excellence in Life and PaleoenvironmentChinese Academy of SciencesNanjing 210008Jiangsu ProvinceChina

The water-living reptile genus Hyphalosaurus was previously discovered in the Lower Cretaceous Yixian Formation bearing the middle Jehol Biota in western liaoning,*** complete skeletons of Hyphalosaurus are reported for the first time from the Jiufotang Formation bearing the late Jehol Biota at two sites in western *** show the typical characteristics of Hyphalosaurus baitaigouensis in terms of the contact between some cranial bones and the number of cervical and dorsal vertebrae,and therefore are assigned to *** discovery extends the stratigraphic range of this species from the Yixian Formation to the overlying Jiufotang *** paper further briefly compares the main characteristics of the two skeletons,summarizes the temporal and spatial distribution of Hyphalosaurus,and discusses the palaeogeographic evolution of western liaoning at the middle and late Jehol Biota stages based on the aquatic habits of Hyphalosaurus and the geological background of western *** analytical results show that the volcanic downwarped lakes,with distinct geographical divisions in western liaoning during the deposition of the Yixian Formation,had not completely disappeared till the deposition of the Jiufotang *** palaeo-lake in the Fuxin-Yixian Basin underwent the process of generation,expansion and shrinkage during the depositional period of the Yixian Formation and finally merged into a large *** palaeo-Dalinghe River,which connected the main basins in western liaoning during the depositional period of the Jiufotang Formation,was formed simultaneously.

关键词： Western liaoning Jehol biota Jiufotang formation Hyphalosaurus baitaigouensis Palaeobiogeography

Chiral thermally activated delayed fluorescence materials for circularly polarized organic light-emitting diodes

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Science China Chemistry 2024年第4期67卷 1097-1116页

作者： li Yuan Yi-Pin Zhang You-Xuan zheng State Key Laboratory of Coordination Chemistry Collaborative Innovation Center of Advanced MicrostructuresJiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China

Chirality is an important natural characteristic of organic molecules,and chiral organic molecules have shown extensive application in areas such as pharmaceutical development and material *** from the ability to achieve circularly polarized luminescence(CPL),chiral luminescent materials have shown potential applications in anti-glare display,optical communication and,3D display,*** to the ability to harvest both singlet and triplet excitons by a fast reverse intersystem crossing process without involving noble metals,chiral thermally activated delayed fluorescence(TADF)materials with point chirality,axial chirality,planar chirality and helical chirality are regarded as the state-of-the-art materials for circularly polarized organic light-emitting diodes(CP-OLEDs).In recent years,the chiral TADF materials and CP-OLEDs have rapidly developed,but unfortunately,the dissymmetry factors(g)are far from the requirement of practical *** ideal emitters and devices should have both high efficiency and a g factor,or at least a balance between these two *** review gives an overview of recent progress in chiral TADF materials,with a particular focus on the chiral skeleton,CPL property and device ***,the molecular design concept,device structure and methods to improve the g factors of chiral materials and CP-OLEDs are also discussed.

关键词： chiral thermally activated delayed fluorescence material chiral skeleton circularly polarized luminescence circularly polarized organic light-emitting diodes dissymmetry factor

Simulation of RFI Cancellation Using Subspace Projection Algorithm for PAF Receiver

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Research in Astronomy and Astrophysics 2024年第1期24卷 237-244页

作者： Peng Wu Jian li Mao-zheng Chen Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China University of Chinese Academy of Sciences Beijing 100049China Xinjiang Key Laboratory of Microwave Technology Urumqi 830011China

The simulation of radio frequency interference(RFI) cancellation by applying a spatial filtering technique for phased array feed(PAF) is presented. In order to better reflect the characteristics of PAF, a new signal model is to add the coupling coefficient among elements of PAF to the conventional array signal model. Then the subspace projection(SP) algorithm is used to cancel RFI from the correlation matrix of the signal, and finally, the 2D power image is drawn. The power variation of signal-of-interest direction and RFI direction before and after using the SP algorithm is analyzed. The new signal model and simulation strategy can be used to test and verify the beamformer.

关键词： methods:analytical techniques:radar astronomy telescopes