Power Frequency Spectral Analysis (PFSA) which evaluates the power of the frequency components at a selected interval, was applied in this preliminary study using a 5MHz Doppler continuous wave flow velocity meter and a modified Edwards Spectraview 500 analyzer. PFSA was used to study the common, internal and external carotid arteries of ten young adult control subjects and 31 patients with angiographically documented carotid bifurcation lesions. Two useful indices are described: (1) the frequency band width at 50% of maximum power (f50%) and (2) the highest frequency recorded (fmax). An f50% wider than 1900 Hz (corresponding to spectrum broadening) identified stenoses as low as a 15% diameter reduction. An fmax higher than 6500 Hz practically always indicated a 50% or greater diameter reduction. Eighty two percent of stenoses with 11-25% diameter reduction were detected, as were 95% of stenoses from 36-50%. All stenoses from 51-99% were identified.
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http://dx.doi.org/10.1161/01.str.15.2.351 | DOI Listing |
Chaos
January 2025
Institute of Technical Physics and Materials Science, HUN-REN Centre for Energy Research, P.O. Box 49, H-1525 Budapest, Hungary.
The dynamics of electric power systems are widely studied through the phase synchronization of oscillators, typically with the use of the Kuramoto equation. While there are numerous well-known order parameters to characterize these dynamics, shortcoming of these metrics are also recognized. To capture all transitions from phase disordered states over phase locking to fully synchronized systems, new metrics were proposed and demonstrated on homogeneous models.
View Article and Find Full Text PDFFront Parasitol
May 2024
Department of Parasitology, Leiden University Medical Center, Leiden, Netherlands.
Detection of spp. DNA in gynaecological samples by quantitative real-time polymerase chain reaction (qPCR) is considered to be the reference diagnostic test for female genital schistosomiasis (FGS). However, qPCR needs expensive laboratory procedures and highly trained technicians.
View Article and Find Full Text PDFFront Child Adolesc Psychiatry
January 2024
National Institute of Public Health, University of Southern Denmark, Copenhagen, Denmark.
Introduction: Regulatory problems of eating, sleeping, and crying in infancy may index mental health vulnerability in older ages, and knowledge is needed to inform strategies to break the developmental trajectories of dysregulation in early childhood. In this study, we examined the prospective associations between infant regulatory problems at the age of 8-10 months identified by community health nurses (CHN) and mental disorders diagnosed in hospital settings in children aged 1-8 years.
Methods: From a cohort of all newborn children in 15 municipalities in the Capital Region of Copenhagen ( = 43,922) we included all children who were examined by CHNs at the scheduled home visit at the age of 8-10 months ( = 36,338).
Infect Dis Model
June 2025
Infectious Disease Epidemiology Group, Weill Cornell Medicine-Qatar, Cornell University, Doha, Qatar.
We aimed to understand to what extent knowledge of the prevalence of one sexually transmitted infection (STI) can predict the prevalence of another STI, with application for men who have sex with men (MSM). An individual-based simulation model was used to study the concurrent transmission of HIV, HSV-2, chlamydia, gonorrhea, and syphilis in MSM sexual networks. Using the model outputs, 15 multiple linear regression models were conducted for each STI prevalence, treating the prevalence of each as the dependent variable and the prevalences of up to four other STIs as independent variables in various combinations.
View Article and Find Full Text PDFBiomed Opt Express
January 2025
State Key Laboratory of Advanced Optical Communication Systems and Networks, School of Electronics, and Center for Quantum Information Technology, Peking University, Beijing 100871, China.
Optically-pumped magnetometer (OPM) has been of increasing interest for biomagnetic measurements due to its low cost and portability compared with superconducting quantum interference devices (SQUID). Miniaturized spin-exchange-relaxation-free (SERF) OPMs typically have limited bandwidth (less than a few hundred Hertz), making it difficult to measure high-frequency biomagnetic signals such as the magnetocardiography (MCG) signal of the mouse. Existing experiments mainly use SQUID systems to measure the signal.
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