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Magneto‑Dielectric Synergy and Multiscale Hierarchical Structure Design Enable Flexible Multipurpose Microwave Absorption and Infrared Stealth Compatibility

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Nano-Micro Letters 2025年第2期17卷 401-416页

作者： Chen Li Leilei Liang Baoshan Zhang yi Yang Guangbin ji School of Electronic Science and Engineering Nanjing UniversityNanjing 210093People’s Republic of China College of Materials Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 210016People’s Republic of China

Developing advanced stealth devices to cope with radar-infrared(IR)fusion detection and diverse application scenarios is increasingly demanded,which faces significant challenges due to conflicting microwave and IR cloaking mechanisms and functional integration ***,we propose a multiscale hierarchical structure design,integrating wrinkled MXene IR shielding layer and flexible Fe_(3)O_(4)@C/PDMS microwave absorption *** top wrinkled MXene layer induces the intensive diffuse reflection effect,shielding IR radiation signals while allowing microwave to pass ***,the permeable microwaves are assimilated into the bottom Fe_(3)O_(4)@C/PDMS layer via strong magneto-electric *** theoretical and experimental optimization,the assembled stealth devices realize a near-perfect stealth capability in both X-band(8–12 GHz)and long-wave infrared(8–14μm)wavelength ***,it delivers a radar cross-section reduction of−20 dB m^(2),a large apparent temperature modulation range(ΔT=70℃),and a low average IR emissivity of ***,the optimal device demonstrates exceptional curved surface conformability,self-cleaning capability(contact angle≈129°),and abrasion resistance(recovery time≈5 s).This design strategy promotes the development of multispectral stealth technology and reinforces its applicability and durability in complex and hostile environments.

关键词： Microwave absorption Radar-infrared compatible stealth Wrinkled MXene Magneto-dielectric synergy Multifunction

Decreased levels of phosphorylated synuclein in plasma are correlated with poststroke cognitive impairment

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Neural Regeneration Research 2025年第9期20卷 2598-2610页

作者： yi Wang Yuning Li Yakun Gu Wei Ma Yuying Guan Mengyuan Guo Qianqian Shao Xunming ji jia Liu Department of Clinical Laboratory Beijing Bo’ai HospitalChina Rehabilitation Research CenterCapital Medical UniversityBeijingChina Beijing Institute of Brain Disorders Laboratory of Brain DisordersMinistry of Science and TechnologyCollaborative Innovation Center for Brain DisordersBeijing Advanced Innovation Center for Big Data-based Precision MedicineCapital Medical UniversityBeijingChina Department of Neurosurgery Xuanwu HospitalCapital Medical UniversityBeijingChina

Poststro ke cognitive impairment is a major secondary effect of ischemic stroke in many patients;however,few options are available for the early diagnosis and treatment of this *** aims of this study were to(1)determine the specific relationship between hypoxic andα-synuclein during the occur of poststroke cognitive impairment and(2)assess whether the serum phosphorylatedα-synuclein level can be used as a biomarker for poststro ke cognitive *** found that the phosphorylatedα-synuclein level was significantly increased and showed pathological aggregation around the cerebral infa rct area in a mouse model of ischemic *** addition,neuronalα-synuclein phosphorylation and aggregation were observed in the brain tissue of mice subjected to chronic hypoxia,suggesting that hypoxia is the underlying cause ofα-synuclein-mediated pathology in the brains of mice with ischemic *** phosphorylatedα-synuclein levels in patients with ischemic stroke were significantly lower than those in healt hy subjects,and were positively correlated with cognition levels in patients with ischemic ***,a decrease in serum high-density lipoprotein levels in stroke patie nts was significantly correlated with a decrease in phosphorylatedα-synuclein *** ischemic stroke mice did not show significant cognitive impairment or disrupted lipid metabolism 14 days after injury,some of them exhibited decreased cognitive function and reduced phosphorylatedα-synuclein *** together,our results suggest that serum phosphorylatedα-synuclein is a potential biomarker for poststroke cognitive impairment.

关键词： biomarker high-density lipoprotein ischemic stroke phosphorylatedα-synuclein poststroke cognitive impairment

Repetitive transcranial magnetic stimulation in Alzheimer’s disease:effects on neural and synaptic rehabilitation

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Neural Regeneration Research 2025年第2期20卷 326-342页

作者： yi ji Chaoyi Yang Xuerui Pang yibing Yan Yue Wu Zhi Geng Wenjie Hu Panpan Hu Xingqi Wu Kai Wang Department of Neurology The First Affiliated Hospital of Anhui Medical UniversityHefeiAnhui ProvinceChina Anhui Province Key Laboratory of Cognition and Neuropsychiatric Disorders HefeiAnhui ProvinceChina Collaborative Innovation Center of Neuropsychiatric Disorders and Mental Health HefeiAnhui ProvinceChina Institute of Artificial Intelligence Hefei Comprehensive National Science CenterHefeiAnhui ProvinceChina Department of Psychology and Sleep Medicine The Second Affiliated Hospital of Anhui Medical UniversityHefeiAnhui ProvinceChina

Alzheimer’s disease is a neurodegenerative disease resulting from deficits in synaptic transmission and *** Alzheimer’s disease brain tends to be hyperexcitable and hypersynchronized,thereby causing neurodegeneration and ultimately disrupting the operational abilities in daily life,leaving patients *** transcranial magnetic stimulation is a cost-effective,neuro-modulatory technique used for multiple neurological *** the past two decades,it has been widely used to predict cognitive decline;identify pathophysiological markers;promote neuroplasticity;and assess brain excitability,plasticity,and *** has also been applied to patients with dementia,because it can yield facilitatory effects on cognition and promote brain recovery after a neurological ***,its therapeutic effectiveness at the molecular and synaptic levels has not been elucidated because of a limited number of *** study aimed to characterize the neurobiological changes following repetitive transcranial magnetic stimulation treatment,evaluate its effects on synaptic plasticity,and identify the associated *** review essentially focuses on changes in the pathology,amyloidogenesis,and clearance pathways,given that amyloid deposition is a major hypothesis in the pathogenesis of Alzheimer’s *** mechanisms associated with repetitive transcranial magnetic stimulation procedures and different pathways mediating gene transcription,which are closely related to the neural regeneration process,are also ***,we discuss the outcomes of animal studies in which neuroplasticity is modulated and assessed at the structural and functional levels by using repetitive transcranial magnetic stimulation,with the aim to highlight future directions for better clinical translations.

关键词： Alzheimer’s disease amyloid deposition apoptotic mechanisms biomarker neural regeneration neurodegeneration repetitive transcranial magnetic stimulation synaptic plasticity

An Improved Higher-Order Time Integration Algorithm for Structural Dynamics

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Computer Modeling in Engineering & Sciences 2021年第2期126卷 549-575页

作者： yi ji Yufeng Xing Institute of Solid Mechanics Beihang UniversityBeijing100083China Shen Yuan Honors College Beihang UniversityBeijing100083China

Based on the weighted residual method,a single-step time integration algorithm with higher-order accuracy and unconditional stability has been proposed,which is superior to the second-order accurate algorithms in tracking long-term *** improving such a higher-order accurate algorithm,this paper proposes a two sub-step higher-order algorithm with unconditional stability and controllable *** the proposed algorithm,a time step interval[t_(k),t_(k)+h]where h stands for the size of a time step is divided into two sub-steps[t_(k),t_(k)+γh]and[t_(k)+γh,t_(k)+h].A non-dissipative fourth-order algorithm is used in the rst sub-step to ensure low-frequency accuracy and a dissipative third-order algorithm is employed in the second sub-step to lter out the contribution of high-frequency ***,two approaches are used to design the algorithm parameterγ.The rst approach determinesγby maximizing low-frequency accuracy and the other determinesγfor quickly damping out highfrequency *** present algorithm usesρ_(∞)to exactly control the degree of numerical dissipation,and it is third-order accurate when 0≤ρ_(∞)<1 and fourth-order accurate whenρ_(∞)=***,the proposed algorithm is self-starting and easy to *** illustrative linear and nonlinear examples are solved to check the performances of the proposed two sub-step higher-order algorithm.

关键词： Time integration algorithm two-sub-step higher-order accuracy controllable dissipation unconditional stability

Q-learning for dynamic channel assignment in cognitive wireless local area network with fibre-connected distributed antennas

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The Journal of China Universities of Posts and Telecommunications 2012年第4期19卷 80-85页

作者： LI yi ji Hong Key Laboratory of Universal Wireless Communications Ministry of EducationBeijing University of Posts and TelecommunicationsBeijing 100876China

Cognitive wireless local area network with fibre-connected distributed antennas （CWLAN-FDA） is a promising and efficient architecture that combines radio over fiber, cognitive radio and distributed antenna technologies to provide high speed/high capacity wireless access at a reasonable cost. In this paper, a Q-learning approach is applied to implement dynamic channel assignment （DCA） in CWLAN-FDA. The cognitive access points （CAPs） select and assign the best channels among the industrial, scientific, and medical （ISM） band for data packet transmission, given that the objective is to minimize external interference and acquire better network-wide performance. The Q-learning method avoids solving complex optimization problem while being able to explore the states of a CWLAN-FDA system during normal operations. Simulation results reveal that the proposed strategy is effective in reducing outage probability and improving network throughput.

关键词： cognitive WLAN fibre-connected distributed antennas Q-learning dynamic channel assignment

Feasibility Study of R134a/R404a Cascade Heat Pump Cycle in Heat Pump Dryers with Electrical Heaters at Low Temperatures

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Journal of Thermal Science 2015年第5期24卷 463-467页

作者： ji Woo Jeong young Lim Lee Dept. of Mechanical Engineering Kongju National University Dept. of Mechanical and Automotive Engineering Kongju National University

Heat pump cycles have been widely applied to dryers for their high efficiency. However, low–efficiency electrical heaters are often used during early drying stage for frozen foods or winter since a standard heat pump cycle cannot operate at low temperature. This study introduced cascade heat pumps replacing electrical heaters to improve dryer performance at low temperatures. Experiments were performed to examine changes in performance of the cascade heat pump dryers in relation to ambient temperature, low-stage cycle mass flow rate, and high-stage cycle mass flow rate. The results showed a significant improvement in low-temperature dryer performance with the introduction of cascade heat pump cycles.

关键词： Cascade cycle R134a/R404a Heat pump dryer COP Energy efficiency

Advanced experimental methods toward understanding biophysicochemical interactions of interfacial biomolecules by using sum frequency generation vibrational spectroscopy

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Science China Chemistry 2014年第12期57卷 1646-1661页

作者： YE Shu ji LUO yi Hefei National Laboratory for Physical Sciences at the Microscale and Department of Chemical Physics University of Science and Technology of China Synergetic Innovation Center of Quantum Information & Quantum Physics University of Science and Technology of China

Sum frequency generation vibrational spectroscopy(SFG-VS)has been demonstrated to be a powerful technique to study the interfacial structures and interactions of biomolecules at the molecular *** most previous studies mainly collected the SFG spectra in the frequency range of 1500–4000 cm-1,which is not always sufficient to describe the detailed interactions at surface and *** knowledge of the complex biophysicochemical interactions between biomolecules and surface requires new ideas and advanced experimental methods for collecting SFG vibrational *** introduced some advanced methods recently exploited by our group and others,including(1)detection of vibration modes in the fingerprint region;(2)combination of chiral and achiral polarization measurements;(3)SFG coupled with surface plasmon polaritons(SPPs);(4)imaging and microscopy approaches;and(5)ultrafast time-resolved SFG *** technique that we integrated with these advanced methods may help to give a detailed and high-spatial-resolution 3D picture of interfacial biomolecules.

关键词： protein cholesterol 3D interfacial structures fingerprint region amide III chiral polarization surface plasmon polaritons time-resolved

Healthy, natural, efficient and tunable lighting: four-package white LEDs for optimizing the circadian effect, color quality and vision performance

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Light(Science & Applications) 2014年第1期3卷 314-322页

作者： ji Hye Oh Su ji Yang young Rag Do Department of Chemistry Kookmin UniversitySeoul 136-702Korea

To date,most current reports on the development and optimization of artificial lighting sources have focused on the energy performance levels and limited color qualities of white light-emitting diodes(LEDs).However,these properties are insufficient in terms of representing all performance levels required when adjusting white LEDs for healthy and smart ***,we introduce essential and advanced figures of merit pertaining to circadian performance as well as vision performance and color *** compare all possible properties of commercialized artificial lighting,daylight and four-package white LEDs which consist of long-wavelength pass dichroic filter(LPDF)-capped,phosphor-converted red,amber and green LEDs(pc-LEDs)and a blue *** show that these tunable four-package white LEDs produce a tunable circadian effect for melatonin suppression/secretion,a high color quality for color perception/reproduction,high efficiency for energy savings and tunable figures of merit for the smart LED lighting market.

关键词： circadian effect color quality solid-state lighting vision performance white LED

The Immersed Interface Hybridized Difference Method for Parabolic Interface Problems

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Numerical Mathematics(Theory,Methods and Applications) 2022年第2期15卷 336-359页

作者： youngmok Jeon Son-young yi Department of Mathematics Ajou UniversitySuwon 16499Republic of Korea Department of Mathematical Sciences The University of Texas at El PasoEl PasoTX 79968USA

We propose several immersed interface hybridized difference methods(IHDMs),combined with the Crank-Nicolson time-stepping scheme,for parabolic interface *** IHDM is the same as the hybrid difference method away from the interface cells,but the finite difference operators on the interface cells are modified tomaintain the same accuracy throughout the entire *** themodification process,we consider virtual extensions of two sub-solutions in the interface cells in such a way that they satisfy certain jump equations between *** propose several different sets of jump equations and their resulting discrete methods for one-and two-dimensional *** numerical results are presented to demonstrate the accuracy and robustness of the proposed methods.

关键词： Parabolic interface problem hybrid difference method immersed interface