Results 71 to 80 of about 11,084 (259)
Energies, 2020 The paper is focused on galvanically isolated series resonant DC–DC converters (SRCs) with a low quality factor of the resonant tank. These converters provide input voltage regulation at fixed switching frequency and good power density.
Vadim Sidorov +2 more
doaj +1 more source
T1 Over Squared Proton Density Ratio to Characterize Multiple Sclerosis Lesions
Annals of Clinical and Translational Neurology, EarlyView.ABSTRACT Objective Differentiating remyelinated from demyelinated lesions in MS remains challenging without histological confirmation. This study introduces the T1‐to‐PD2 ratio (TPR) imaging approach and evaluates its ability to characterize MS lesions alongside other quantitative MRI (qMRI) metrics. Methods Thirty individuals with MS (mean age: 47.5 ±
Sarah J. Wright +10 more
wiley +1 more source
Upper Cervical Cord Area as a Biomarker of Conversion to Secondary Progressive Multiple Sclerosis
Annals of Clinical and Translational Neurology, EarlyView.ABSTRACT Objective This study assessed whether upper cervical cord area (UCCA) measured on routine brain MRI can serve as a biomarker of conversion to SPMS. Methods This is a single‐center retrospective cohort study of RRMS patients with cross‐sectional and longitudinal analyses of clinical and MRI data. Future SPMS converters were matched by age, sex,
Nabil K. El Ayoubi +8 more
wiley +1 more source
Lithium Tantalate Bulk Acoustic Resonator for Piezoelectric Power Conversion
2025 23rd International Conference on Solid-State Sensors, Actuators and Microsystems (Transducers)We present the first lithium tantalate (LT) thickness-extensional (TE) mode bulk acoustic resonators designed for piezoelectric power conversion, showcasing a low temperature coefficient of frequency (TCF) of -13.56 ppm/K. These resonators also exhibit high quality factors (Q) of 1698, and electromechanical coupling coefficients ($k^2$) of 8.8%, making
Yao, Ziqian +5 more
openaire +2 more sources
Ultra-low power parametric frequency conversion in a silicon microring resonator
Optics Express, 2008 We demonstrate parametric wavelength conversion via four-wave mixing using ultra-low peak pump powers of a few milliwatts in a micrometer-scale silicon device. The response time of our device is 100 ps allowing for implementation in high-bandwidth optical communications.
Amy C, Turner +3 more
openaire +2 more sources
Arthritis Care &Research, EarlyView.Systemic sclerosis (SSc) is a rare autoimmune disease defined by immune dysregulation, vasculopathy, and progressive fibrosis of the skin and internal organs. Despite advances in care, major complications such as interstitial lung disease (ILD) and myocardial involvement remain the leading causes of morbidity and mortality.
Cristiana Sieiro Santos +2 more
wiley +1 more source
Arthritis Care &Research, EarlyView.Objective To investigate the association between rheumatoid arthritis (RA) and coronary artery calcium (CAC) prevalence, incidence, and progression over four years in adults without prior cardiovascular disease. Methods A case‐cohort study within the Brazilian Longitudinal Study of Adult Health (ELSA‐Brasil) included 585 participants (86 patients with ...
Patrícia Fonseca Estrada +7 more
wiley +1 more source
A Compact Spin‐Coated Graphene UWB Antenna for Breast Tumor Detection
Advanced Engineering Materials, EarlyView.A compact, spin‐coated graphene ultra‐wideband patch antenna designed for breast tumor detection, capable of distinguishing between malignant and benign tumors. This innovative antenna can serve as an effective initial screening tool, particularly in resource‐limited settings such as rural areas, where access to advanced medical equipment like MRI and ...
Raja Rashidul Hasan +9 more
wiley +1 more source
ON THE RESONANCE CHARACTERISTICS OF THE FLOAT TYPE WAVE POWER CONVERSION DEVICE
Doboku Gakkai Ronbunshuu B, 2010 本研究では，ワイヤ，フロート，カウンタウェイトなどを組合わせた可動物体型波力発電装置の共振特性の検討を行っている．共振解析モデルでは時々刻々のフロート変位と水面変位の相対座標を用いている．フロートの運動方程式では，フロート・流体間の相互作用力を，波強制力，付加質量，造波減衰により評価しており，これと回転体の力学と発電機関連の力学を組み合わせて方程式系を構成している．共振特性解析は，波の作用下で稼動状態にあるフロートの上下動の振幅を，波の振幅と比較することにより検討している．さらに発生電力，トルクやワイヤ張力などの物理量の波周期による変化を評価している．また，装置が安全に稼働しかつ発生電力が大きい条件を探るため，フロートが一部没水を維持できる条件下で発生電力を大きくする装置諸元を調べている．
TANEURA, Keisuke +5 more
openaire +2 more sources
Advanced Engineering Materials, EarlyView.This article presents the design, modeling, and characterization of air‐pressure–actuated programmable vibroacoustic metamaterials (PVAMM). The study focuses on leveraging air pressure to dynamically tune resonance frequencies for effective noise attenuation.
William Kaal +2 more
wiley +1 more source