An all solid-state, megawatt-class high power microwave system featuring a silicon carbide (SiC) photoconductive semiconductor switch (PCSS) and a ferrimagnetic-based, coaxial nonlinear transmission line (NLTL) is presented. A 1.62 cm(2), 50 kV 4H-SiC PCSS is hard-switched to produce electrical pulses with 7 ns full width-half max (FWHM) pulse widths at 2 ns risetimes in single shot and burst-mode operation. The PCSS resistance drops to sub-ohm when illuminated with approximately 3 mJ of laser energy at 355 nm (tripled Nd:YAG) in a single pulse. Utilizing a fiber optic based optical delivery system, a laser pulse train of four 7 ns (FWHM) signals was generated at 65 MHz repetition frequency. The resulting electrical pulse train from the PCSS closely follows the optical input and is utilized to feed the NLTL generating microwave pulses with a base microwave-frequency of about 2.1 GHz at 65 MHz pulse repetition frequency (prf). Under typical experimental conditions, the NLTL produces sharpened output risetimes of 120 ps and microwave oscillations at 2-4 GHz that are generated due to damped gyromagnetic precession of the ferrimagnetic material's axially pre-biased magnetic moments. The complete system is discussed in detail with its output matched into 50 Ω, and results covering MHz-prf in burst-mode operation as well as frequency agility in single shot operation are discussed.
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http://dx.doi.org/10.1063/1.4804196 | DOI Listing |
Sports (Basel)
December 2024
Training and Sports Performance Study Group, Department of Physical Education, Federal University of Paraiba, João Pessoa 58051-900, Brazil.
Despite strength training (ST) being well characterized by professional runners, little is known about the inclusion of ST models for recreational runners. Thus, the present study aimed to investigate the presence of ST in the training practices of recreational runners, with a focus on understanding its characteristics and the motivations of recreational athletes for including ST in their routines. To this end, 801 recreational runners (493 male and 308 female) completed a structured questionnaire regarding their training habits, the inclusion of ST, and its characteristics, concerning the type of ST, training volume, and the reasons for including ST in their training programs.
View Article and Find Full Text PDFQ J Exp Psychol (Hove)
January 2025
Department of Psychology, University of Guelph, Ontario, Canada.
Decision perseveration is consistently observed in recognition tests, such that judgments tend to repeat (e.g., "old" responses tend to follow "old" responses) across trials.
View Article and Find Full Text PDFBr J Gen Pract
January 2025
University Medical Centre Utrecht, Department of General Practice & Nursing Sciences, Julius Center for Health Sciences and Primary Care, Utrecht, Netherlands.
Aim: To develop and internally validate a model predicting life-threatening events for out-of-hours primary care callers with shortness of breath.
Method: This cross-sectional study includes data from 1,952 patients with shortness of breath who called out-of-hours primary care between September 2020 and August 2021. Four logistic regression models were developed with life-threatening events as the outcome.
Phys Eng Sci Med
January 2025
Institute of Digital Technologies for Personalized Healthcare (MeDiTech), University of Applied Sciences and Arts of Southern Switzerland, Via Pobiette, Manno, 6928, Manno, Switzerland.
The analysis of repetitive hand movements and behavioral transition patterns holds particular significance in detecting atypical behaviors in early child development. Early recognition of these behaviors holds immense promise for timely interventions, which can profoundly impact a child's well-being and future prospects. However, the scarcity of specialized medical professionals and limited facilities has made detecting these behaviors and unique patterns challenging using traditional manual methods.
View Article and Find Full Text PDFSports Med Open
January 2025
Department of Sports Science and Clinical Biomechanics, SDU Sport and Health Sciences Cluster, University of Southern Denmark, Odense, Denmark.
Background: A small number of reviews have explored lower- versus higher-volume training in non-athletes, but the growing challenge of congested schedules in team sports highlights the need to synthesize evidence specific to team sport athletes. Thus, the objectives of this systematic review with meta-analysis are twofold: (i) to summarize the primary physiological and physical fitness outcomes of lower-volume versus higher-volume training interventions in team sports players; and (ii) to compare the effects of lower-volume training with higher, considering the training modalities used.
Methods: We conducted searches across key databases, including PubMed, Scopus, SPORTDiscus, and Web of Science.
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