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We compare multiple temporal pulse characterization techniques in three different pulse duration regimes from 15 fs to sub-5 fs, as there are no available standards yet for measuring such ultrashort pulses. To accomplish this, a versatile post-compression platform was developed, where the 100 fs near infrared pulses were post-compressed to the sub-two-cycle regime in a hybrid, three-stage configuration. After each stage, the duration of the compressed pulse was measured with the d-scan, TIPTOE and SRSI techniques and the retrieved temporal intensity profiles, spectrum and spectral phases were compared. Spectral homogeneity was also measured with an imaging spectrometer to understand the input coupling conditions of the temporal measurements. Our findings suggest that the different devices give similar results in terms of temporal intensity profile, however they are extremely sensitive to alignment and to beam quality, especially in the case of the shortest pulses. We address specific steps of measurement procedures, which paves the way towards the standardization of pulse characterization in the near future.
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http://dx.doi.org/10.1364/OE.509583 | DOI Listing |
Beilstein J Nanotechnol
September 2025
B. I. Stepanov Institute of Physics, National Academy of Sciences of Belarus, 220072 Minsk, Belarus.
In this study, silicon nanoparticles (NPs) were produced by pulsed laser ablation in a liquid, aiming to investigate the influence of a laser beam profile on the properties of the resultant NPs. Morphology, inner structure, and phase composition of the formed NPs were characterized by means of ultraviolet-visible spectroscopy, high-resolution transmission electron microscopy, and Raman and photoluminescence spectroscopies, and the correlation of the NP properties with the laser beam profile was studied. Three different beam profiles were selected, namely, a Bessel beam produced using an axicon, an annular profile formed using a combination of an axicon and a converging lens, and a Gaussian beam focused on the surface of a Si target using the same converging lens.
View Article and Find Full Text PDFLasers Surg Med
September 2025
Department of Dermatology, the Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China.
Objectives: Post-acne erythema (PAE), a common consequence of acne, is characterized by capillary dilation and erythema, which significantly impact facial aesthetics and quality of life. This study aims to evaluate and compare the efficacy and safety of intense pulsed light (DPL) and 1064 nm Q-switched Nd:YAG laser in treating PAE.
Methods: This prospective, randomized, self-controlled, evaluator-blinded clinical trial compared DPL and 1064 nm Q-switched Nd:YAG laser treatments on one side of the face, with biweekly sessions for 6 weeks.
J Cardiovasc Electrophysiol
September 2025
Department of Cardiology, Stefan Cardinal Wyszynski Province Specialist Hospital, Lublin, Poland.
Introduction: Wave speed (WS) mapping, enabled by omnipolar technology, allows for real-time visualization of local conduction velocity (CV). Its utility in ventricular tachycardia (VT) ablation has not been fully characterized.
Methods And Results: We describe a case series of patients undergoing VT ablation in which WS mapping was applied alongside established techniques such as peak frequency (PF) mapping and isochronal late activation mapping (ILAM).
Med Eng Phys
October 2025
Departament of Electronics and Biomedical Engineering, School of Electrical and Computer Engineering (DEEB/FEEC), University of Campinas (UNICAMP), Campinas, SP, Brazil; National Laboratory for Study of Cell Calcium (LabNECC), Center for Biomedical Engineering (CEB), UNICAMP, Campinas, SP, Brazil.
High-intensity, external electric fields (HIEF) have been used in research and therapy for abnormal generation/propagation of the cardiac electrical activity (e.g., defibrillation), and for promoting access of membrane-impermeant molecules into the cytosol through electropores.
View Article and Find Full Text PDFInt J Food Microbiol
September 2025
Department of Food Science and Nutrition, Faculty of Food Engineering, University of Campinas, Campinas, SP, Brazil. Electronic address:
This study investigated the presence of Pseudomonas aeruginosa and heterotrophic bacteria in 1150 samples of bottled mineral water. P. aeruginosa was initially isolated using membrane filtration on selective agar and subsequently confirmed by PCR.
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