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Primordial black holes and curvature perturbations from false vacuum islands

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Science China(Physics,Mechanics & Astronomy) 2024年第9期67卷 58-72页

作者： Rong-Gen Cai Yu-shi hao Shao-jiang Wang School of Physical Science and Technology Ningbo UniversityNingbo 315211China CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Asia Pacific Center for Theoretical Physics Pohang 37673Republic of Korea

Recently,much attention has been focused on the false vacuum islands that are flooded by an expanding ocean of true-vacuum bubbles slightly later than most of the other parts of the *** delayed decay regions will accumulate locally larger vacuum energy density by staying in the false vacuum longer than those already transited into the true vacuum.A false vacuum island with thus acquired density contrast of a super-horizon size will evolve locally from radiation dominance to vacuum dominance,creating a local baby Universe that can be regarded effectively as a local closed *** such density contrasts of super-horizon sizes can ever grow large enough to exceed the threshold of gravitational collapse,primordial black holes will form similar to those collapsing curvature perturbations on super-horizon scales induced by small-scale enhancements during *** not,such density contrasts can still induce curvature perturbations potentially observable *** this paper,we revisit and elaborate on the generations of primordial black holes and curvature perturbations from delayed-decayed false vacuum islands during asynchronous first-order phase transitions with fitting formulas convenient for future model-independent studies.

关键词： first-order phase transitions primordial black holes curvature perturbations

A newly unraveled 13.6-year oscillation from GPS displacements and its potential implications for the dynamic reference frame

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Science China Earth Sciences 2024年第10期67卷 3204-3212页

作者： hao DING Weiping jiang School of Geodesy and Geomatics Hubei Luojia LaboratoryWuhan UniversityWuhan 430079China GNSS Research Center Wuhan UniversityWuhan 430079China

Numerous practical geodetic and geophysical applications necessitate precise measurements of GNSS displacements at the millimeter or sub-millimeter level. To attain such precision, it is imperative to identify and analyze the unidentified decadal signals inherent in the GPS displacements. In this research, we employ the optimal sequence estimation method to effectively detect an about 13.6-year oscillational signal with an excited amplitude of 3.6±1.2 mm in the U-components of the GPS displacements. It is noteworthy that this signal demonstrates a consistent spatial pattern characterized by the spherical harmonic Y_(2,-2). We conduct a comparative analysis with the 13.6-year oscillation observed in length-of-day variations(and geomagnetic records), finding that they are in reverse phase. After eliminating the Earth's external excitation sources through the utilization of two distinct in-situ hydrological records, we suggest that the 13.6-year GPS signal may come from the internal motions within the Earth. However, the specific excitation source and the detailed physical mechanism remain uncertain. Additionally, we develop a mathematical displacement model to explain the 13.6-year signal. Our findings indicate that this signal can result in displacements of up to 1.37 mm and velocity effects of 0.63 mm/yr(for U-component) at maximum. These results underscore the necessity of incorporating this 13.6-year signal into the construction and maintenance of a dynamic reference frame at the millimeter level.

关键词： GPS displacements Decadal changes 13.6-year oscillation Displacement model Dynamic reference frame

3D‑Printed Carbon‑Based Conformal Electromagnetic Interference shielding Module for Integrated Electronics

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Nano-Micro Letters 2024年第5期16卷 87-101页

作者： Shaohong shi Yuheng jiang hao Ren Siwen Deng Jianping Sun Fangchao Cheng Jingjing Jing Yinghong Chen State Key Laboratory of Featured Metal Materials and Life‑Cycle Safety for Composite Structures School of ResourcesEnvironment and MaterialsGuangxi UniversityNo.100Daxuedong RoadNanning 530004People’s Republic of China State Key Laboratory of Polymer Materials Engineering Polymer Research Institute of Sichuan UniversitySichuan UniversityNo.24 South Section 1Yihuan RoadChengdu 610065People’s Republic of China

Electromagnetic interference shielding(EMI SE)modules are the core com-ponent of modern ***,the tra-ditional metal-based SE modules always take up indispensable three-dimensional space inside electronics,posing a major obstacle to the integra-tion of *** innovation of integrating 3D-printed conformal shielding(c-SE)modules with packaging materials onto core electronics offers infinite possibilities to satisfy ideal SE func-tion without occupying additional ***,the 3D printable carbon-based inks with various proportions of graphene and carbon nanotube nanoparticles are well-formulated by manipulating their rheological ***,the free-constructed architectures with arbitrarily-customized structure and multifunctionality are created via 3D *** particular,the SE performance of 3D-printed frame is up to 61.4 dB,simultaneously accompanied with an ultralight architecture of 0.076 g cm^(-3) and a superhigh specific shielding of 802.4 dB cm3 g^(-1).Moreover,as a proof-of-concept,the 3D-printed c-SE module is in situ integrated into core electronics,successfully replacing the traditional metal-based module to afford multiple functions for electromagnetic compatibility and thermal ***,this scientific innovation completely makes up the blank for assembling carbon-based c-SE modules and sheds a brilliant light on developing the next generation of high-performance shielding materials with arbitrarily-customized structure for integrated electronics.

关键词： 3D printing Carbon-based nanoparticles Conformal electromagnetic interference shielding Integrated electronics

Fault-tolerant flocking control against multiple malicious agents under geometric configuration containment

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Science China(Information Sciences) 2024年第10期67卷 261-282页

作者： Chencheng ZHANG hao YANG Bin jiang College of Automation Engineering Nanjing University of Aeronautics and Astronautics Institute of Engineering and Technology (ENTEG) University of Groningen

Flocking control in the presence of malicious decisions is a crucial research topic since agents in swarms are likely to suffer from security issues in practice. This paper considers a swarm containing malicious agents that deliberately alter their controller parameters and disrupt the swarm by causing collisions,divisions, and escapes. Two possible malicious scenarios are considered. The first is that one malicious agent acts selectively on a subset of its neighbors and the second is that multiple malicious agents are either scattered or clustered together. To achieve the flocking control objective:(1) containment conditions based on specific geometric configurations are established;(2) hierarchical fault-tolerant flocking control methods based on those containment conditions are proposed. Compared to existing research dealing with malicious agents in swarms, our approach aims to contain rather than remove them. This guarantees the completeness of the task and takes agents' motions into consideration. Simulations show the effectiveness of the proposed methods.

关键词： flocking control fault-tolerant control multiple malicious agents geometric configuration

Intermittent Theta Burst Stimulation Attenuates Cognitive Deficits and Alzheimer’s Disease-Type Pathologies via ISCA1-Mediated Mitochondrial Modulation in APP/PS1 Mice

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Neuroscience Bulletin 2024年第2期40卷 182-200页

作者： Yang Zhu hao Huang Zhi Chen Yong Tao Ling-Yi Liao shi-hao Gao Yan-jiang Wang Chang-Yue Gao Department of Rehabilitation Medicine Daping HospitalArmy Medical UniversityChongqing 400042China Department of Neurology and Center for Clinical Neuroscience Daping HospitalArmy Medical UniversityChongqing 400042China Department of Special Medicine Daping HospitalArmy Medical UniversityChongqing 400042China

Intermittent theta burst stimulation(iTBS),a time-saving and cost-effective repetitive transcranial magnetic stimulation regime,has been shown to improve cognition in patients with Alzheimer’s disease(AD).However,the specific mechanism underlying iTBS-induced cognitive enhancement remains *** studies suggested that mitochondrial functions are modulated by magnetic ***,we showed that iTBS upregulates the expression of iron-sulfur cluster assembly 1(ISCA1,an essential regulatory factor for mitochondrial respiration)in the brain of APP/PS1 *** vivo and in vitro studies revealed that iTBS modulates mitochondrial iron-sulfur cluster assembly to facilitate mitochondrial respiration and function,which is required for ***,iTBS rescues cognitive decline and attenuates AD-type pathologies in APP/PS1 *** present study uncovers a novel mechanism by which iTBS modulates mitochondrial respiration and function via ISCA1-mediated iron-sulfur cluster assembly to alleviate cognitive impairments and pathologies in *** provide the mechanistic target of iTBS that warrants its therapeutic potential for AD patients.

关键词： Intermittent theta burst stimulation Alzheimer’s disease Iron-sulfur cluster assembly 1 Mitochondrial dysfunction Neurodegeneration

Chronic infectious unilateral giant thyroid cyst related to diabetes mellitus:A case report

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World Journal of Clinical Cases 2024年第8期12卷 1497-1503页

作者： jiang-Bo Liu shi-Lei Zhang Wen-Long jiang Hai-Kuan Sun hao-Chen Yang Department of Thyroid and Breast Surgery The First Affiliated HospitalCollege of Clinical MedicineHenan University of Science and TechnologyLuoyang 471000Henan ProvinceChina Clinical Medicine School The First Clinical CollegeChongqing Medical UniversityChongqing 400016China

BACKGROUND Patients rarely develop complicated infections in thyroid ***,we describe a patient with chronic infected unilateral giant thyroid cyst related to diabetes mellitus(DM).CASE SUMMARY A 66-year-old male was admitted due to an evident neck lump for 5 d after approximately 40 years of gradually progressive neck mass and 7 years of *** ultrasound and computed tomography scan showed a giant lump in the left thyroid gland *** was diagnosed with a large thyroid nodule complicated by tracheal dislocation and had surgical *** exploration revealed evident inflammatory edema and exudation between the left anterior neck muscles,the nodule and glandular ***,inflammatory lesions did not affect major neck ***,a left partial thyroidectomy was *** observation showed that the cystic thyroid mass consisted of extensive cystic wall calcification and was rich in massive rough sand-like calculi content and purulent *** pathology confirmed benign thyroid cyst with chronic *** The progression of this chronic infectious unilateral giant thyroid cyst may have been related to DM,and identifying blood vessels involvement can prevent serious complications during operation.

关键词： Thyroid nodule Infection Diabetes mellitus Surgery Case report

Novel Sum-of-Sinusoids Simulation Channel Modeling for 6G Multiple-Input Multiple-Output Vehicle-to-Everything Communications

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China Communications 2024年第1期21卷 242-259页

作者： hao jiang Hongming Zhang Ting Liu College of Artificial Intelligence Nanjing University of Information Science and Technology210044China National Mobile Communications Research Laboratory Southeast UniversityNanjing 210096China School of Information and Communication Engineering Beijing University of Posts and TelecommunicationsChina

In this paper,a statistical cluster-based simulation channel model with a finite number of sinusoids is proposed for depicting the multiple-input multiple-output(MIMO)communications in vehicleto-everything(V2X)*** the proposed sum-of-sinusoids(SoS)channel model,the waves that emerge from the transmitter undergo line-of-sight(LoS)and non-line-of-sight(NLoS)propagation to the receiver,which makes the model suitable for describing numerous V2X wireless communication scenarios for sixth-generation(6G).We derive expressions for the real and imaginary parts of the complex channel impulse response(CIR),which characterize the physical propagation characteristics of V2X wireless *** statistical properties of the real and imaginary parts of the complex CIRs,i.e.,autocorrelation functions(ACFs),Doppler power spectral densities(PSDs),cross-correlation functions(CCFs),and variances of ACFs and CCFs,are derived and *** results are generated and match those predicted by the underlying theory,demonstrating the accuracy of our derivation and *** proposed framework and underlying theory arise as an efficient tool to investigate the statistical properties of 6G MIMO V2X communication systems.

关键词： complex CIRs LoS and NLoS propagation components MIMO V2X communication environments SoS simulation channel model statistical properties

Numerical insight into heat transfer enhancement by granules inner-migration in a moving bed:A performance comparison between slanted-stick and plow-shaped agitator

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Particuology 2024年第6期89卷 109-116页

作者： Binfan jiang hao Pei Dehong Xia Haiyang Wang School of Energy and Environmental Engineering University of Science and Technology BeijingBeijing 100083China Shunde Graduate School of University of Science and Technology Beijing Guangdong 528399China Jianlong Group&USTB Joint Laboratory Beijing 100083China

Waste heat recovery of high-temperature granules is one of the most promising sustainable energy supply and carbon reduction ways for industry.A moving bed indirect heat exchanger(MBIHE)with inner-migration was proposed for granular heat *** migration and the enhanced heat transfer induced by two types of agitators(i.e.,agitator with slanted stick A_(s)and with plow-shaped surface A_(p))in the MBIHE are analyzed based on DEM coupled with *** to the effective agitation,the average heat transfer coefficient in the granule side is enhanced to∼3 times compared to that without *** heat recovery efficiency in the moving bed reached more than 70%with the agitations of either A_(s)or A_(p).The heat efficiency of A_(s)is∼7%higher than that of A_(p),but with at least 60%greater rotational *** ensure reliable agitation,the A_(p)is suggested to be adopted in the MBIHE to induce granule migration.

关键词： Waste heat recovery High-temperature granule Granule migration Heat transfer enhancement Industry energy saving

Numerical and experimental investigation into the evolution of the shock wave when a muzzle jet impacts a constrained moving body

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Defence Technology（防务技术） 2024年第3期33卷 317-326页

作者： Zijie Li hao Wang Changshun Chen Kun jiang School of Energy and Power Engineering Nanjing University of Science and TechnologyNanjing 210016China

The gun-track launch system is a new special launch device that connects the track outside the *** it is constrained by the track,the characteristics of development of the muzzle jet differ from those of the traditional muzzle ***,it changes from freely developing to doing so in a constrained manner,where this results in an asymmetric direction of flow as well as spatio-temporal coupling-induced interference between various shock waves and the formation of *** this background,the authors of this article formulate and consider the development and characteristics of evolution of the muzzle jet as it impacts a constrained moving *** designed simulations to test the gun-track launch system,and established a numerical model based on the dynamic grid method to explore the development and characteristics of propagation of disturbances when the muzzle jet impacted a constrained moving *** also considered models without a constrained track for the sake of *** results showed that the muzzle jet assumed a circumferential asymmetric shape,and tended to develop in the area above the *** the test platform was close to the ground,the muzzle jet was subjected to reflections from it that enhanced the development and evolution of various forms of shock waves and vortices in the muzzle jet to exacerbate its rate of distortion and asymmetric *** in turn led to significant differences in the changes in pressure at symmetric points that would otherwise have been *** results of a comparative analysis showed that the constrained track could hinder the influence of reflections from the ground on the muzzle jet to some extent,and could reduce the velocity of the shock waves inducing the motion of the muzzle as well as the Mach number of the moving *** work here provides a theoretical basis and the requisite technical support for applications of the gun-track launch *** also sheds light on the

关键词： Shock wave/vortex interference Muzzle jet Constrained boundary Dynamic grid