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Communications in Theoretical Physics 2024年第7期76卷 74-82页

作者： Yan-Hong Yao Xin-he Meng School of Physics and Astronomy Sun Yatsen University 2 Daxue RoadTangjiaZhuhaiChina School of Physics Nankai University 94 Weijin RoadNankaiTianjinChina

The Hubble tension persists as a challenge in *** early dark energy(EdE)models,initially considered the most promising for alleviating the Hubble tension,fall short of addressing the issue without exacerbating other tensions,such as the S_(8)*** that a negative dark matter(dM)equation of state(EoS)parameter is conducive to reduce the value of the σ_(8)parameter,we extend the axion-like EdE model in this paper by replacing the cold dark matter(CdM)with dM characterized by a constant EoS w_(dm)(referred to as WdM hereafter).We then impose constraints on this axion-like EdE extension model,along with three other models:the axion-like EdE model,ΛWdM,and Λ*** constraints are derived from a comprehensive analysis incorporating data from the Planck 2018 cosmic microwave background,baryon acoustic oscillations,and the Pantheon compilation,as well as a prior on H_(0)(i.e.H_(0)=73.04±1.04,based on the latest local measurement by Riess et al)and a Gaussianized prior on S_(8)(i.e.S_(8)=0.766±0.017,determined through the joint analysis of KId1000+BOSS+2dLenS).We find that although the new model maintains the ability to alleviate the Hubble tension to~1.4σ,it still exacerbates the S_(8)tension to a level similar to that of the axion-like EdE model.

关键词： Hubble tension early dark energy noncold dark matter S8 tension

dietary glycine supplementation enhances syntheses of creatine and glutathione by tissues of hybrid striped bass(Morone saxatilis ♀ × Morone chrysops ♂) fed soybean meal-based diets

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Journal of Animal Science and Biotechnology 2024年第5期15卷 1996-2011页

作者： Wenliang he Xinyu Li Guoyao Wu department of Animal Science Texas A&M UniversityCollege StationTX 77843USA

Background We recently reported that supplementing glycine to soybean meal-based diets is necessary for the optimum growth of 5-to 40-g(Phase-I)and 110-to 240-g(Phase-II)hybrid striped bass(HSB),as well as their intestinal *** glycine serves as an essential substrate for syntheses of creatine and glutathione(GSH)in mammals(e.g.,pigs),little is known about these metabolic pathways or their nutritional regulation in *** study tested the hypothesis that glycine supplementation enhances the activities of creatine-and GSH-forming enzymes as well as creatine and GSH availabilities in tissues of hybrid striped bass(HSB;Morone saxatilis♀×Morone chrysops♂).Methods Phase-I and Phase-II HSB were fed a soybean meal-based diet supplemented with 0%,1%,or 2%glycine for 8 *** the end of the 56-d feeding,tissues(liver,intestine,skeletal muscle,kidneys,and pancreas)were collected for biochemical *** In contrast to terrestrial mammals and birds,creatine synthesis occurred primarily in skeletal muscle from all *** liver was most active in GSH synthesis among the HSB tissues *** Phase-I HSB,supplementation with 1%or 2%glycine increased(Pd hepatic GSH(8%–11%),while reducing(Phepatic GSH sulfide(GSSG)/GSH ratios by 14%–15%,compared with the 0-glycine group;there were no differences(P>0.05)in these variables between the 1%and 2%glycine *** Phase-II HSB,supplementation with 1%and 2%glycine increased(Pd GSH in the muscle(15%–27%)and liver(11%–20%)in a dose-dependent manner,with reduced ratios of hepatic GSSG/GSH in the 1%or 2%glycine *** all HSB,supplementation with 1%and 2%glycine dose-dependently increased(Pdinotransferase(22%–41%)and hepaticγ-glutamylcysteine synthetase(17%–37%),with elevated activities of intramuscular guanidinoacetate methyltransferase and hepatic GSH synthetase a

关键词： Amino acids Creatine Fish Glutathione Glycine Nutrition

Uniqueness of the Reissner-Nordstrom metric near the null infinity

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Science China Mathematics 2024年第8期67卷 1933-1956页

作者： Xiaokai he Xiaoning Wu Naqing Xie School of Mathematics and Statistics Hunan First Normal UniversityChangsha 410205China Institute of Mathematics Academy of Mathematics and Systems Science and Hua Loo-Keng Key Laboratory of MathematicsChinese Academy of SciencesBeijing 100190China School of Mathematical Sciences Fudan UniversityShanghai 200433China

In the Newman-Penrose formalism,we prove that the Reissner-Nordstrom metric is the only asymptotically fat,static,axially symmetric,Petrov type-d analytic solution of the electro-vacuum Einstein-Maxwell equations near... 详细信息

关键词： uniqueness theorem Reissner-Nordstrom metric Newman-Penrose formalism

Highly sensitive flexible strain sensor based on the two-dimensional semiconductor tellurium with a negative gauge factor

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Science China(Information Sciences) 2024年第7期67卷 295-304页

作者： Jiarui he Yusong QU Shengyao CheN Cong WANG Lena dU Xiaoshan dU Yuanyuan ZheNG Guozhong ZHAO he TIAN College of Mathematics and Physics Beijing University of Chemical Technology School of Integrated Circuits Tsinghua University Beijing China & The Beijing National Research Center for Information Science and Technology (BNRist)Tsinghua University CAS Center for Excellence in Nanoscience National Center for Nanoscience and Technology &University of Chinese Academy of Sciences Beijing Key Lab of Terahertz Spectroscopy and Imaging Key Lab of Terahertz OptoelectronicsMinistry of Education Department of Physics Capital Normal University

Research on flexible strain sensors has advanced rapidly in recent years, with particular attention being devoted to two-dimensional(2d) semiconductor materials owing to their exceptional mechanical and electrical properties that are conducive to sophisticated sensing performance. However, resistive strain sensors based on 2d semiconductor materials typically exhibit positive gauge factors(GF), while materials for strain sensors with a negative GF remain elusive. We have identified a trend of reduction in the band gap of the emerging 2d semiconductor material tellurium(Te) under strain in simulations reported in past research,and have observed a negative GF in the Te-based strain sensor. In this study, we combined Te with a flexible polyethylene terephthalate(PET) substrate to manufacture a flexible strain sensor with a significantly negative GF. The results of tests revealed that the Te-based strain sensor achieved an impressive maximum sensitivity of-139.7 within a small range of bending-induced strain(hermore, it exhibited excellent linearity and good cyclic stability, and was successfully applied to monitor limb movements. The work here verifies the significant potential for the use of Te-based strain sensors in next-generation flexible electronics.

关键词： 2d semiconductor materials 2d tellurium flexibleelectronics strain sensors negative gauge factor high sensitivity

Molecular evolution of Toll-like receptors in rodents

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Integrative Zoology 2024年第3期19卷 371-386页

作者： Qianqian SU Yi CheN Hongxuan he College of Forestry Central South University of Forestry and TechnologyChangshaChina National Research Center for Wildlife-Borne diseases Institute of ZoologyChinese Academy of SciencesBeijingChina

Toll-like receptors(TLRs),the key sensor molecules in vertebrates,trigger the innate immunity and prime the adaptive immune *** TLR family of rodents,the largest order of mammals,typically contains 13 TLR ***,a clear picture of the evolution of the rodent TLR family has not yet emerged and the TLR evolutionary patterns are unclear in rodent ***,we analyzed the natural variation and the evolutionary processes acting on the TLR family in rodents at both the interspecific and population *** results showed that rodent TLRs were dominated by purifying selection,but a series of positively selected sites(PSSs)primarily located in the ligand-binding domain was also *** numbers of PSSs differed among TLRs,and nonviralsensing TLRs had more PSSs than those in viral-sensing ***-conversion events were found between TLR1 and TLR6 in most rodent *** genetic analyses showed that TLR2,TLR8,and TLR12 were under positive selection in Rattus norvegicus and ***,whereas positive selection also acted on TLR5 and TLR9 in the former species,as well as TLR1 and TLR7 in the latter ***,we found that the proportion of polymorphisms with potentially functional change was much lower in viral-sensing TLRs than in nonviral-sensing TLRs in both of these rat *** findings revealed the first thorough insight into the evolution of the rodent TLR genetic variability and provided important novel insights into the evolutionary history of TLRs over long and short timescales.

关键词： adaptive evolution gene conversion positive selection rodents Toll-like receptors

Recycling the spent electronic materials to construct a highperformance Cu_(1.94)S/ZnS heterostructure anode of sodium-ion batteries

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Nano Research 2024年第5期17卷 4006-4015页

作者： Xiaowei he Tianshuai Wang Lidong Tian Qiuyu Zhang School of Chemistry and Chemical Engineering Xi’an Key Laboratory of Functional Organic Porous MaterialsKey Laboratory of Special Functional and Smart Polymer Materials of Ministry of Industry and Information TechnologyNorthwestern Polytechnical UniversityXi’an 710072China Chongqing Science and Technology Innovation Center of Northwestern Polytechnical University Chongqing 401135China College of Materials Science and Engineering Xi’an University Science and TechnologyXi’an 710054China

heterostructure engineering by coupling different nanocrystals has received extensive attention because it can enhance the reaction kinetics of the anode of sodium-ion batteries(SIBs).However,constructing high-quality heterostructure anode materials through green and environmentally friendly methods remains a ***,we have proposed a simple one-step method by recycling the electronic waste metal materials to synthesize the Cu_(1.94)S/ZnS heterostructure *** with the experimental analysis and first principle calculations,we find that the synergistic effect of different components in heterostructure structures can significantly enhance the reversible capacity and rate performance of anode *** on the constructed Cu_(1.94)S/ZnS anode,we obtain a superior reversible capacity of 440 mAh·g^(-1) at 100 mA·g^(-1) and 335 mAh·g^(-1) after 3000 cycles at 2000 mA·g^(-1).Our work sheds new light on designing high-rate and capacity anodes for SIBs through the greenness synthesis method.

关键词： sodium-ion batteries heterostructure reversible capacity environmentally synthesis process

“Blocking and rebalance” mechanism-guided design strategies of bimetallic doped 2d a-phosphorus carbide as efficient catalysts for N2 electroreduction

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Journal of Energy Chemistry 2024年第10期97卷 68-78页

作者： Cheng he Jianglong Ma Shen Xi Wenxue Zhang State Key Laboratory for Mechanical Behavior of Materials School of Materials Science and Engineering Xi'an Jiaotong University School of Materials Science and Engineering Chang'an University

Compared to single atom catalysts（SACs）,the introduction of dual atom catalysts（dACs） has a significantly positive effect on improving the efficiency in the electrocatalytic nitrogen reduction reaction（NRR） which provides an environmental alternative to the Haber-Bosch ***,the research on the mechanism and strategy of designing bimetallic combinations for better performance is still in its early ***,based on "blocking and rebalance" mechanism,45 combinations of bimetallic pair doped α-phosphorus carbide（TMATMB@PC） are investigated as efficient NRR catalysts through density functional theory and machine learning *** a multi-step screening,the combinations of TiV,TiFe,MnMo,and FeW exhibit highly efficient catalytic performance with significantly lower limiting potentials（-0.17,-0.18,-0.14,and-0.30 V,respectively）.Excitingly,the limiting potential for CrMo and CrW combinations is 0 V,which are considered to be extremely suitable for the NRR *** mechanism of "blocking and rebalance" is revealed by the exploration of charge transfer for phosphorus atoms in electron blocking ***,the descriptor φ is proposed with machine learning,which provides design strategies and accurate prediction for finding efficient *** work not only offers promising catalysts TMATMB@PC for NRR process but also provides design strategies by presenting the descriptor φ.

关键词： 2d α-phosphorus carbide dACs Inherent attributes Machine learning Nitrogen reduction reaction

Imaging of human parafoveal area with large field of view in adaptive optics line scanning ophthalmoscope

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Journal of Innovative Optical health Sciences 2024年第6期17卷 41-51页

作者： Wen Kong Yiwei Chen Guohua Shi Yi he department of Biomedical Engineering University of Science and Technology of ChinaHefei 230041P.R.China Jiangsu Key Laboratory of Medical Optics Suzhou Institute of Biomedical Engineering and TechnologyChinese Academy of SciencesSuzhou 215163P.R.China Center for Excellence in Brain Science and Intelligence Technology Chinese Academy of SciencesShanghai 200031P.R.China Key Laboratory of Myopia of State health Ministry and Key Laboratory of Visual Impairment and Restoration of ShanghaiShanghai 200003P.R.China

The parafoveal area,with its high concentration of photoreceptors andfine retinal capillaries,is crucial for central vision and often exhibits early signs of pathological *** current adaptive optics scanning laser ophthalmoscope(AOSLO)provides an excellent tool to acquire accurate and detailed information about the parafoveal area with cellular ***,limited by the scanning speed of two-dimensional scanning,thefield of view(FOV)in the AOSLO system was usually less than or equal to 2,and the stitching for the parafoveal area required dozens of images,which was time-consuming and ***,almost half of patients are unable to obtain stitched images because of their *** solve this problem,we integrate AO technology with the line-scan imaging method to build an adaptive optics line scanning ophthalmoscope(AOLSO)system with a larger *** the AOLSO,afocal spherical mirrors in pairs are nonplanar arranged and the distance and angle between optical elements are optimized to minimize the aberrations,two cylinder lenses are orthogonally placed before the imaging sensor to stretch the point spread function(PSF)for su±ciently digitizing light *** human retinal images show the whole parafoveal area with 55FOV,60 Hz frame rate and cellular *** advantage of the 5FOV of the AOLSO,only 9 frames of the retina are captured with several minutes to stitch a montage image with an FOV of 99,in which photoreceptor counting is performed within approximately 5*** AOLSO system not only provides cellular resolution but also has the capability to capture the parafoveal region in a single frame,which offers great potential for noninvasive studying of the parafoveal area.

关键词： Adaptive optics line scanning retinal imaging system parafoveal capillary vasculature.

Fe-Cr-Y_2O_3 MICRO-CRYSTALLINE COATINGS dEPOSITEd BY SERIES ELECTRO-PULSE dISCHARGE

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Acta Metallurgica Sinica(English Letters) 2002年第4期15卷 331-338页

作者： Q. Xu,Y.d. he,d.R. Wang,H.B. Qi,Z.W. Li and W.Gao Beijing Key Laboratory for Corrosion, Erosion and Surface Technology, University of Science and Technology Beijing, Beijing 100083, China department of Chemical and Material Engineering, The University of Beijing Key Laboratory for Corrosion Erosion and Surface Technology University of Science and Technology Beijing

A new technique-series electro-pulse discharge (SEPd)-was developed as a sur-face coating process. In this technique, both positive and negative poles of a pulse power were used as the depositing electrodes with the substrate alloy as an induction electrode. Fe-Cr and Fe-Cr-Y2O3 micro-crystalline coatings were deposited on stain-less steel (Fe-18Cr-8Ni) surfaces. Oxidation at 950℃ in ambient air showed that the coatings greatly improved the oxidation resistance of the steel. The addition of dis-persed Y2O3 nano-particles into the alloy coatings was found to further reduce the scaling rate and enhance the adhesion of oxide scales.

关键词： series electro-pulse discharge Fe-Cr-Y2O3 micro-crystalline al-loy coating high-temperature oxidation

Symbology of Feynman integrals from twistor geometries

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Science China(Physics,Mechanics & Astronomy) 2024年第3期67卷 44-59页

作者： Song he Jiahao Liu Yichao Tang Qinglin Yang School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUCASHangzhou 310024China CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China International Centre for Theoretical Physics Asia-Pacific Beijing 100049 Peng Huanwu Center for Fundamental Theory Hefei 230026China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China

We study the symbology of planar Feynman integrals in dimensional regularization by considering geometric configurations in momentum twistor space corresponding to their leading singularities(LS). Cutting propagators in momentum twistor space amounts to intersecting lines associated with loop and external dual momenta, including the special line associated with the point at infinity, which breaks dual conformal symmetry. We show that cross-ratios of intersection points on these lines, especially those on the infinity line, naturally produce symbol letters for Feynman integrals in d = 4-2∈, which include and generalize their LS. At one loop, we obtain all symbol letters using intersection points from quadruple cuts for integrals up to pentagon kinematics with two massive corners, which agree perfectly with canonical differential equation(CdE) results. We then obtain all two-loop letters, for up to four-mass box and one-mass pentagon kinematics, by considering more intersections arising from two-loop cuts. Finally we comment on how cluster algebras appear from this construction, and importantly how we may extend the method to non-planar integrals.

关键词： Feynman integrals symbol letters twistor geometry