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Elliptically polarized high-order harmonic generation of Ar atom in an intense laser field

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Chinese Physics B 2024年第5期33卷 453-457页

作者：胡杰王一琛景秋霜姜威王革文赵逸文肖礴梁红静马日 institute of Atomic and Molecular Physics Jilin UniversityChangchun 130012China college of Science Jilin Institute of Chemical TechnologyJilin 132022China

High-order harmonic generation(HHG) of Ar atom in an elliptically polarized intense laser field is experimentally investigated in this ***,the anomalous ellipticity dependence on the laser ellipticity(ε) in the lower-order harmonics is observed,specifically in the 13rd-order,which displays a maximal harmonic intensity at ε ≈ 0.1,rather than at ε = 0 as *** contradicts the general trend of harmonic yield,which typically decreases with the increase of laser *** this study,we attribute this phenomenon to the disruption of the symmetry of the wave function by the Coulomb effect,leading to the generation of a harmonic with high *** finding provides valuable insights into the behavior of elliptically polarized harmonics and opens up a potential way for exploring new applications in ultrafast spectroscopy and light–matter interactions.

关键词： high-order harmonic generation Coulomb effect elliptically polarized intense laser field

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An object detection approach with residual feature fusion and second-order term attention mechanism

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CAAI Transactions on Intelligence Technology 2024年第2期9卷 411-424页

作者： Cuijin Li Zhong Qu Shengye Wang college of Computer Science and Technology Chongqing University of Posts and TelecommunicationsChongqingChina college of Electronic Information Chongqing Institute of EngineeringChongqingChina

Automatically detecting and locating remote occlusion small objects from the images of complex traffic environments is a valuable and challenging *** the boundary box location is not sufficiently accurate and it is difficult to distinguish overlapping and occluded objects,the authors propose a network model with a second-order term attention mechanism and occlusion ***,the backbone network is built on *** a method is designed for the feature extraction network based on an item-wise attention mechanism,which uses the filtered weighted feature vector to replace the original residual fusion and adds a second-order term to reduce the information loss in the process of fusion and accelerate the convergence of the ***,an objected occlusion regression loss function is studied to reduce the problems of missed detections caused by dense *** experimental results demonstrate that the authors’method achieved state-of-the-art performance without reducing the detection *** mAP@.5 of the method is 85.8%on the Foggy_cityscapes dataset and the mAP@.5 of the method is 97.8%on the KITTI dataset.

关键词： artificial intelligence computer vision image processing machine learning neural network object recognition

Application of plant DNA metabarcoding of lake sediments for monitoring vegetation compositions on the Tibetan Plateau

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Science China Earth Sciences 2024年第11期67卷 3594-3609页

作者： Kai WU Kai LI Weihan JIA Kathleen R.STOOF-LEICHSENRING Ulrike HERZSCHUH Jian NI Mengna LIAO Fang TIAN college of Life Sciences Zhejiang Normal University Polar Terrestrial Environmental Systems Research Group Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research institute of Environmental Science and Geography University of Potsdam institute of Biochemistry and Biology University of Potsdam college of Resource Environment and Tourism Capital Normal University

Benefiting from the rapid development of environmental DNA(eDNA) technologies, sedimentary DNA(sedDNA)emerges as a promising tool for monitoring plant compositions in remote regions. The Tibetan Plateau(TP), renowned for its harsh environment and numerous ponds and lakes, presents a potentially demanding region for the application of sedDNA on vegetation investigations. Here, we used the g and h universal primers for the P6 loop region of the chloroplast trn L(UAA)intron to amplify plant DNA in surface sediments from 59 ponds and small lakes on the southwestern TP. The applicability and limitations of using plant DNA metabarcoding for modern vegetation monitoring and palaeo-vegetation reconstructions have been assessed by comparing sedDNA, pollen, and vegetation survey data. Our results showed that plant DNA metabarcoding recorded 186 terrestrial taxa, of which 30.1% can be identified at the species level. The plant sedDNA approach can effectively disclose the dominant plant taxa(including Asteraceae, Cyperaceae and Poaceae) and significant vegetation assemblages in the vicinity of the investigated sites. The number of taxa and taxonomic resolution of plant sedDNA exceeded that of pollen analysis(75 taxa detected, 5.3% can be identified at species level). Unlike pollen that retains a broad spectrum of regional plant signals(including Pinus and Artemisia), plant sedDNA mirrors very local plants, underscoring its utility in local vegetation monitoring and reconstructions. To conclude, plant DNA metabarcoding of(small) lake sediments warrant increased attention in the future for local vegetation monitoring and reconstructions on the TP.

关键词： Sedimentary DNA (sedDNA) Metabarcoding Pollen Vegetation composition Tibetan Plateau

Mitophagy in neurodegenerative disease pathogenesis

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Neural Regeneration Research 2024年第5期19卷 998-1005页

作者： Kan Yang Yuqing Yan Anni Yu Ru Zhang Yuefang Zhang Zilong Qiu Zhengyi Li Qianlong Zhang Shihao Wu Fei Li Department of Developmental and Behavioural Pediatric&Child Primary Care Brain and Behavioural Research Unit of Shanghai Institute for Pediatric Research and MOE-Shanghai Key Laboratory for Children’s Environmental HealthXinhua HospitalShanghai Jiao Tong University School of MedicineShanghaiChina Center for Excellence in Brain Science and Intelligence Technology Institute of NeuroscienceState Key Laboratory of NeuroscienceCAS Key Laboratory of Primate NeurobiologyChinese Academy of SciencesShanghaiChina college of Materials and Chemical Engineering Hunan Institute of EngineeringXiangtanHunan ProvinceChina School of Medicine Yunnan UniversityKunmingYunnan ProvinceChina Songjiang Research institute Shanghai Jiao Tong University School of MedicineShanghaiChina Neurosurgery Department Kunming Yenan HospitalKunmingYunnan ProvinceChina

Mitochondria are critical cellular energy resources and are central to the life of the *** selectively clears damaged or dysfunctional mitochondria through autophagic machinery to maintain mitochondrial quality control and *** neurons are postmitotic and consume substantial energy,thus require highly efficient mitophagy pathways to turn over damaged or dysfunctional *** evidence indicates that mitophagy is pivotal to the pathogenesis of neurological ***,more work is needed to study mitophagy pathway components as potential therapeutic *** this review,we briefly discuss the characteristics of nonselective autophagy and selective autophagy,including ERphagy,aggrephagy,and *** then introduce the mechanisms of Parkin-dependent and Parkin-independent mitophagy pathways under physiological ***,we summarize the diverse repertoire of mitochondrial membrane receptors and phospholipids that mediate ***,we review the critical role of mitophagy in the pathogenesis of neurodegenerative diseases including Alzheimer’s disease,Parkinson’s disease,and amyotrophic lateral ***,we discuss recent studies considering mitophagy as a potential therapeutic target for treating neurodegenerative ***,our review may provide novel views to better understand the roles of mitophagy in neurodegenerative disease pathogenesis.

关键词： Alzheimer’s disease amyotrophic lateral sclerosis autophagy mitochondria mitophagy mitophagy receptor Parkin Parkinson’s disease PINK1

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Hexokinase 1 and 2 mediates glucose utilization to regulate the synthesis of kappa casein via ribosome protein subunit 6 kinase 1 in bovine mammary epithelial cells

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Animal Nutrition 2024年第1期16卷 338-349页

作者： Tianyu Yang Jia Guo Han Song Osmond Datsomor Yuhang Chen Maocheng Jiang Kang Zhan Guoqi Zhao institute of Animal Culture Collection and Application College of Animal Science and Technology Yangzhou University

Glucose plays a vital part in milk protein synthesis through the mTOR signaling pathway in bovine mammary epithelial cells(BMEC). The objectives of this study were to determine how glucose affects hexokinase(HK) activity in BMEC and investigate the regulatory effect of HK in kappa casein(CSN3)synthesis via the mechanistic target of rapamycin complex 1(mTORC1) signaling pathway in BMEC. For this, HK1 and HK2 were knocked out in BMEC using the CRISPR/Cas9 system. The gene and protein expression, glucose uptake, and cell proliferation were measured. We found that glucose uptake, cell proliferation, CSN3 gene expression levels, and expression of HK1 and HK2 increased with increasing glucose concentrations. Notably, glucose uptake was significantly reduced in HK2 knockout(HK2KO)BMEC treated with 17.5 mM glucose. Moreover, under the same glucose treatment conditions, the proliferative ability and abundance of CSN3 were significantly diminished in both HK1 knockout(HK1KO)and HK2KO BMEC compared with that in wild-type BEMC. We further observed that the phosphorylation levels of ribosome protein subunit 6 kinase 1(S6K1) were reduced in HK1KO and HK2KO BMEC following treatment with 17.5 mM glucose. As expected, the levels of glucose-6-phosphate and the m RNA expression levels of glycolysis-related genes were decreased in both HK1KO and HK2KO BMEC following glucose treatment. These results indicated that the knockout of HK1 and HK2 inhibited cell proliferation and CSN3 expression in BMEC under glucose treatment, which may be associated with the inactivation of the S6K1 and inhibition of glycolysis.

关键词： Glucose Hexokinase Milk protein Mechanistic target of rapamycin complex 1 signaling pathway Bovine mammary epithelial cell Kappa casein

Grouping Decision Algorithm for Dynamic Terminals in Random Access Networks

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Journal of Communications and Information Networks 2024年第2期9卷 176-183页

作者： Hongliang Sun Tongfei Chen Chuangye Zhao Mengxin Chen college of Information and Control Engineering Jilin Institute of Chemical TechnologyJilin 132022China

This paper proposes a grouping decision algorithm for random access networks with the carrier sense multiple access (CSMA) mechanism, which can balance the traffic load and solve the hidden terminal issue. Considering the arrival characteristics of terminals and quality of service (QoS) requirements, the traffic load is evaluated based on the effective bandwidth theory. Additionally, a probability matrix of hidden terminals is constructed to take into account the dynamic nature of hidden terminal relations. In the grouping process, an income function is established with a view to the benefits of decreasing the probability of hidden terminal collisions and load balancing. Then, we introduce the grey wolf optimization (GWO) algorithm to implement the grouping decision. Simulation results demonstrate that the grouping algorithm can effectively alleviate the performance degradation and facilitate the management of network resources.

关键词： random access network hidden terminal collision probability effective bandwidth traffic load grey wolf optimization

A water-stable high-voltage P3-type cathode for sodium-ion batteries

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Chinese Chemical Letters 2024年第9期35卷 507-513页

作者： Shengyu Zhao Xuan Yu Yufeng Zhao institute for Sustainable Energy&college of Sciences Shanghai UniversityShanghai 200444China

The Na-deficient P3-type layered oxide cathode material usually experience complex in-plane Na^(+)/vacancy ordering rearrangement and undesirable P3-O3 phase transitions in the high-voltage region,leading to inferior cycling ***,they exhibit unsatisfactory stability when exposed to water for extended *** address these challenges,we propose a Cu/Ti co-doped P3-type cathode material(Na_(0.67)Ni_(0.3)Cu_(0.03)Mn_(0.6)Ti_(0.07)O_(2)),which effectively mitigates Na^(+)/vacancy ordering and suppresses P3-O3 phase transitions at high *** a result,the as-prepared sample exhibited outstanding cyclic performance,with 81.9%retention after 500 cycles within 2.5–4.15 V,and 75.7%retention after300 cycles within 2.5–4.25 ***,it demonstrates enhanced Na^(+)transport kinetics during desodiation/sodiation and reduced growth of charge transfer impedance(R_(ct))after various ***,the sample showed superb stability against water,exhibiting no discernible degradation in structure,morphology,or electrochemical *** co-doping strategy provides new insights for innovative and prospective cathode materials.

关键词： Sodium ion batteries P3-type materials Phase transition Na^(+)/vacancy ordering Water-stable cathode

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Biotic and abiotic stresses on honeybee health

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Integrative Zoology 2024年第3期19卷 442-457页

作者： Zheguang LIN Siyi SHEN Kang WANG Ting JI Apicultural Research institute College of Animal Science and TechnologyYangzhou UniversityYangzhouChina

Honeybees are the most critical pollinators providing key ecosystem services that underpin crop production and sustainable *** a backdrop of rapid global change,this eusocial insect encounters a succession of stressors during nesting,foraging,and *** mites,together with vectored viruses,have been recognized as central biotic threats to honeybee health,while the spread of invasive giant hornets and small hive beetles also increasingly threatens colonies *** of agrochemicals,including acaricides used for mite treatment,and other pollutants of the environment have been widely documented to affect bee health in various ***,expanding urbanization,climate change,and agricultural intensification often result in the destruction or fragmentation of flower-rich bee *** anthropogenic pressures exerted by beekeeping management practices affect the natural selection and evolution of honeybees,and colony translocations facilitate alien species invasion and disease *** this review,the multiple biotic and abiotic threats and their interactions that potentially undermine bee colony health are discussed,while taking into consideration the sensitivity,large foraging area,dense network among related nestmates,and social behaviors of honeybees.

关键词： abiotic stressor Apis biotic stressor colony losses interaction effect pollinator decline

Fabrication of a 25.2 T NMR magnet for an extreme condition user facility in China

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National Science Review 2024年第7期11卷 62-64页

作者： Hui Han Yun Shang MRI Research institute Department of RadiologyWeill Medical College of Cornell University

An ultra-high field magnet（>20 T）is desirable for studying the characteristics of new materials under extreme magnetic conditions [1]. Additionally,such field strength will result in resonance frequencies close to or greater than 1 GHz when applied to the study of1H signals from biomolecules by nuclear magnetic resonance（NMR）,which will lead to a higher signal-to-noise ratio, better sensitivity and a higher spectral resolution due to increased chemical shift dispersion [2].

关键词： NMR double pancake high temperature superconducting magnet ultra-high field