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On self-affine tiles that are homeomorphic to a ball

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science China Mathematics 2024年第1期67卷 45-76页

作者： Jorg M.Thuswaldner Shu-Qin Zhang Mathematics and Statistics University of LeobenLeoben 8700Austria School of Mathematics and Statistics Zhengzhou UniversityZhengzhou 450001China

Let M be a 3×3 integer matrix which is expanding in the sense that each of its eigenvalues is greater than 1 in modulus and let D?Z^(3)be a digit set containing|det M|*** the unique nonempty compact set T=T(M,D)defined by the set equation MT=T+D is called an integral self-affine tile if its interior is *** D is of the form D={0,v,...,(|det M|-1)v},we say that T has a collinear digit *** present paper is devoted to the topology of integral self-affine tiles with collinear digit *** particular,we prove that a large class of these tiles is homeomorphic to a closed 3-dimensional ***,we show that in this case,T carries a natural CW complex structure that is defined in terms of the intersections of T with its neighbors in the lattice tiling{T+z:z∈Z^(3)}induced by *** CW complex structure is isomorphic to the CW complex defined by the truncated octahedron.

关键词： self-afine sets tiles and tilings low-dimensional topology truncated octahedron

Arctic Sea Ice Variations in the First Half of the 20th Century:A New Reconstruction Based on Hydrometeorological Data

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Advances in Atmospheric sciences 2024年第8期41卷 1483-1495,1686-1693页

作者： Vladimir A.SEMENOV Tatiana A.ALDONINA Fei LI Noel Sebastian KEENLYSIDE Lin WANG A.M.Obukhov Institute of Atmospheric Physics RAS Moscow 119017Russia Institute of Geography RAS Moscow 119017Russia Geophysical Institute University of Bergen and Bjerknes Centre for Climate ResearchBergen 5007Norway Nansen Environmental and Remote Sensing Center Bergen 5007Norway Center for Monsoon System Research Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China

The shrinking Arctic sea-ice area(SIA) in recent decades is a striking manifestation of the ongoing climate *** of the Arctic sea ice have been continuously observed by satellites since 1979, relatively well monitored since the 1950s, but are highly uncertain in the earlier period due to a lack of observations. Several reconstructions of the historical gridded sea-ice concentration(SIC) data were recently presented based on synthesized regional sea-ice observations or by applying a hybrid model–empirical approach. Here, we present an SIC reconstruction for the period1901–2019 based on established co-variability between SIC and surface air temperature, sea surface temperature, and sea level pressure patterns. The reconstructed sea-ice data for March and September are compared to the frequently used Had ISST1.1 and SIBT1850 datasets. Our reconstruction shows a large decrease in SIA from the 1920 to 1940 concurrent with the Early 20th Century Warming event in the Arctic. Such a negative SIA anomaly is absent in Had ISST1.1 data. The amplitude of the SIA anomaly reaches about 0.8 mln km^(2) in March and 1.5 mln km^(2) in September. The anomaly is about three times stronger than that in the SIBT1850 dataset. The larger decrease in SIA in September is largely due to the stronger SIC reduction in the western sector of the Arctic Ocean in the 70°–80°N latitudinal zone. Our reconstruction provides gridded monthly data that can be used as boundary conditions for atmospheric reanalyses and model experiments to study the Arctic climate for the first half of the 20th century.

关键词： Arctic sea ice Arctic climate early 20th century warming climate variability

Microlensing bias on the detection of strong lensing gravitational wave

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science China(Physics,Mechanics & Astronomy) 2024年第6期67卷 156-165页

作者： Xikai Shan Xuechun Chen Bin Hu Guoliang Li Institute for Frontier in Astronomy and Astrophysics Beijing Normal UniversityBeijing 102206China Department of Astronomy Beijing Normal UniversityBeijing 100875China Purple Mountain Observatory Chinese Academy of SciencesNanjing 210023China

Identifying strong lensing gravitational wave(SLGW)events is of utmost importance in astrophysics as we approach the historic first detection of SLGW amidst the growing number of gravitational wave(GW)***,one crucial method for identifying SLGW signals involves assessing the overlap of parameters between two ***,the distribution of discrete matter,such as stars and sub-halos,within the strong lensing galaxy can imprint a wave optical(WO)effect on the SLGW *** frequency dependent imprints introduce biases in parameter estimation and impact SLGW *** this study,we assess the influence of the stellar microlensing field embedded in a strong lensing *** findings demonstrate that the WO effect reduces the detection efficiency of SLGW by 5%-50%for various false alarm probabilities per pair(FAPper pair).Specifically,at an FAPper pairof 10^(-5),the detection efficiency decreases from~10%to~5%.Consequently,the presence of the microlensing field can result in missing half of the strong lensing ***,the microlensing WO effect introduces a noticeable bias in intrinsic parameters,particularly for chirp mass and mass ***,it has tiny influence on extrinsic *** all parameters,~30%of events exhibit a 1σparameter bias,~12%exhibit a 2σparameter bias,and~5%exhibit a 3σparameter bias.

关键词： gravitational wave gravitational strong lensing gravitational micro lensing wave optical effect

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Terahertz high-sensitivity SIS mixer based on Nb–AlN–NbN hybrid superconducting tunnel junctions

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Chinese Physics B 2024年第5期33卷 681-686页

作者：刘博梁刘冬姚明金骏达王争李婧史生才 Artem Chekushkin Michael Fominsky Lyudmila Filippenko Valery Koshelets Purple Mountain Observatory Chinese Academy of SciencesNanjing 210023China School of Astronomy and Space sciences University of Science and Technology of ChinaHefei 230026China Kotel'nikov Institute of Radio Engineering and Electronics Russian Academy of SciencesMoscow 125009Russia

The terahertz band,a unique segment of the electromagnetic spectrum,is crucial for observing the cold,dark universe and plays a pivotal role in cutting-edge scientific research,including the study of cosmic environments that support life and imaging black ***-sensitivity superconductor–insulator–superconductor(SIS)mixers are essential detectors for terahertz astronomical telescopes and interferometric *** to the commonly used classical Nb/AlO_(x)/Nb superconducting tunnel junction,the Nb/AlN/NbN hybrid superconducting tunnel junction has a higher energy gap voltage and can achieve a higher critical current *** makes it particularly promising for the development of ultra-wideband,high-sensitivity coherent detectors or mixers in various scientific research *** this paper,we present a superconducting SIS mixer based on Nb/AlN/NbN parallel-connected twin junctions(PCTJ),which has a bandwidth extending up to490 GHz–720 *** best achieved double-sideband(DSB)noise temperature(sensitivity)is below three times the quantum noise level.

关键词： SIS mixer terahertz gap voltage critical current density hybrid superconducting tunnel junction

Correlating dynamic relaxation and viscoelasticity in metallic glasses

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science China(Physics,Mechanics & Astronomy) 2024年第5期67卷 81-90页

作者： GuangHui Xing Qi Hao Fan Zhu Yun-Jiang Wang Yong Yang Hidemi Kato Eloi Pineda Si Lan JiChao Qiao School of Mechanics Civil Engineering and ArchitectureNorthwestern Polytechnical UniversityXi'an 710072China State Key Laboratory of Nonlinear Mechanics Institute of MechanicsChinese Academy of SciencesBeijing 100190China School of Engineering science University of Chinese Academy of SciencesBeijing 100049China Department of Mechanical Engineering College of EngineeringCity University of Hong KongHong Kong 999077China Department of Materials science and Engineering College of EngineeringCity University of Hong KongHong Kong 999077China Institute for Materials Research Tohoku UniversitySendai 980-8577Japan Department of Physics Institute of Energy TechnologiesUniversitat Politècnica de CatalunyaBarceona 9Spain School of Material science and Engineering Herbert Gleiter Institute of NanoscienceNanjing University of Science and Technology.Nanjing 210094China State Key Laboratory of Clean and Efficient Turbomachinery Power Equipment Northwestern Polytechnical UniversityXi'an 710072China

Relaxation dynamics,essential for the structural evolution of non-equilibrium systems like glassy materials,remain ***,we explore relaxation dynamics and viscoelastic properties in three types of metallic glasses with distinctβrelaxation *** systems with significantβrelaxation,stress relaxation and creep experiments reveal a transition from two-step to one-step relaxation with rising ***,such a phenomenon is absent in systems with weakerβ*** model the two-step relaxation process using a double Kohlrausch-Williams-Watts equation,and the obtained relaxation times elegantly adhere to the Arrhenius *** combining fitted activation energies with theoretical analysis,we conclusively attribute these relaxation processes toβrelaxation andαrelaxation,***,we analyze the relaxation time spectra of two processes and establish a comprehensive picture linking dynamic relaxation with *** study provides new strategies for probing the complex relaxation behaviors of glasses from the perspective of viscoelasticity.

关键词： creep relaxation glasses

Atherosclerosis originating from childhood:Specific features

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Journal of Biomedical Research 2024年第3期38卷 233-240页

作者： Anastasia V.Poznyak Alexey A.Yakovlev MikhailА.Popov Elena B.Zhigmitova Vasily N.Sukhorukov Alexander N.Orekhov Institute for Atherosclerosis Research Moscow 121609Russia Federal Research and Clinical Center of Intensive Care Medicine and Rehabilitology Moscow 109240Russia Department of Cardiac Surgery Moscow Regional Research and Clinical InstituteMoscow 129110Russia Laboratory of Angiopathology Institute of General Pathology and PathophysiologyMoscow 125315Russia

Atherosclerosis is extremely ***,it is considered a disease of older people,who most often experience problems with the heart and blood *** much attention from the scientific community has been paid to studying the association between aging and atherosclerosis,as well as its consequences,there is evidence that atherosclerosis occurs at an early *** may form both during intrauterine development and in *** plays an important role in childhood atherosclerosis,along with previous infectious diseases and excess weight of both the child and the *** the present review,we examined the development of atherosclerosis and the prerequisites in childhood.

关键词： atherosclerosis childhood pediatrics cardiovascular disease

Quantum dynamics within curved thin layers with deviation

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Chinese Physics B 2024年第7期33卷 502-507页

作者：程润赵浩罗翠柏周璇王必利李延标王骏 Physics Department of Basic Department Army Engineering University of PLANanjing 211101China National Laboratory of Solid State Microstructure Collaborative Innovation Center of Advanced Microstructuresand School of PhysicsNanjing UniversityNanjing 210093China School of Physics and Electronics Hunan UniversityChangsha 410082China Department of Physics Anhui Normal UniversityWuhu 241002China

Combining the deviation between thin layers' adjacent surfaces with the confining potential method applied to the quantum curved systems,we derive the effective Schr?dinger equation describing the particle constrained within a curved layer,accompanied by a general geometric potential V_(gq) composed of a compression-corrected geometric potential V_(gq)~*and a novel potential V_(gq)~(**) brought by the *** this analysis to the cylindrical layer emerges two types of deviation-induced geometric potential,resulting from the the cases of slant deviation and tangent deviation,respectively,which strongly renormalizes the purely geometric potential and contribute to the energy spectrum based on a very substantial deepening of bound states they offer.

关键词： confining potential method quantum mechanics curved thin layer

Enhancing milk quality and modulating rectal microbiota of dairy goats in starch‑rich diet:the role of bile acid supplementation

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Journal of Animal science and Biotechnology 2024年第2期15卷 862-877页

作者： Qingyan Yin Junjian Yu Jiaxiao Li Tianci Zhang Tianyu Wang Yufei Zhu Jun Zhang Junhu Yao College of Animal science and Technology Northwest A&F UniversityYangling 712100ShaanxiP.R.China Key Laboratory of Livestock Biology Northwest A&F UniversityYangling 712100ShaanxiP.R.China DAYU Bioengineering(Xi’an)Industrial Development Research Institute Xi’an 710000ShaanxiP.R.China

Background Diets rich in starch have been shown to increase a risk of reducing milk fat content in dairy *** bile acids(BAs)have been used as a lipid emulsifier in monogastric and aquatic animals,their effect on ruminants is not well *** study aimed to investigate the impact of BAs supplementation on various aspects of dairy goat physiology,including milk composition,rumen fermentation,gut microbiota,and BA *** We randomly divided eighteen healthy primiparity lactating dairy goats(days in milk=100±6 d)into two groups and supplemented them with 0 or 4 g/d of BAs undergoing 5 weeks of feeding on a starch-rich *** results showed that BAs supplementation positively influenced milk yield and improved the quality of fatty acids in goat *** supplementation led to a reduction in saturated fatty acids(C16:0)and an increase in monounsaturated fatty acids(cis-9 C18:1),resulting in a healthier milk fatty acid *** observed a significant increase in plasma total bile acid concentration while the proportion of rumen short-chain fatty acids was not ***,BAs supplementation induced significant changes in the composition of the gut microbiota,favoring the enrichment of specific bacterial groups and altering the balance of microbial *** analysis revealed associations between specific bacterial groups(Bacillus and Christensenellaceae R-7 group)and BA types,suggesting a role for the gut microbiota in BA *** prediction analysis revealed notable changes in pathways associated with lipid metabolism,suggesting that BAs supplementation has the potential to modulate lipid-related *** These findings highlight the potential benefits of BAs supplementation in enhancing milk production,improving milk quality,and influencing metabolic pathways in dairy *** research is warranted to elucidate the underlying mechanisms and explore the broader implications of these findi

关键词： Bile acids Dairy goats Lipid metabolism Gut microbiota

Boson star superradiance

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science China(Physics,Mechanics & Astronomy) 2024年第6期67卷 69-78页

作者： He-Yu Gao Paul M.Saffin Yi-Jie Wang Qi-Xin Xie Shuang-Yong Zhou School of Physical sciences University of Science and Technology of ChinaHefei 230026China School of Physics and Astronomy University of NottinghamUniversity ParkNottingham NG72RDUK Interdisciplinary Center for Theoretical Study University of Science and Technology of ChinaHefei 230026China Peng Huanwu Center for Fundamental Theory Hefei 230026China

Recently,it has been realized that in some systems internal space rotation can induce energy amplification for scattered waves,similar to rotation in real *** particularly,it has been shown that energy extraction is possible for a Q-ball,a stationary non-topological soliton that is coherently rotating in its field *** this paper,we generalize the analysis to the case of boson stars,and show that the same energy extraction mechanism still works for boson stars.

关键词： superradiance boson star field space rotation

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