We investigated the influence of thermal initiation pathway on the irradiance threshold for laser induced breakdown in transparent, absorbing and scattering phantoms. We observed a transition from laser-induced optical breakdown to laser-induced thermal breakdown as the absorption coefficient of the medium is increased. We found that the irradiance threshold after correction for the path length dependent absorption and scattering losses in the medium is lower due to the thermal pathway for the generation of seed electrons compared to the laser-induced optical breakdown. Furthermore, irradiance threshold gradually decreases with the increase in the absorption properties of the medium. Creating breakdown with lower irradiance threshold that is specific at the target chromophore can provide intrinsic target selectivity and improve safety and efficacy of skin treatment methods that use laser induced breakdown.
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http://dx.doi.org/10.1364/BOE.6.001234 | DOI Listing |
Cancer Treat Res Commun
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Department of Biostatistics, School of Public Health, Hamadan University of Medical Sciences, Hamadan, Iran.
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View Article and Find Full Text PDFQuant Imaging Med Surg
January 2025
Department of Radiation Oncology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.
Background: Volumetric modulated arc therapy (VMAT) is a popular radiotherapy technique in the clinic. As consisting of hundreds of control points in a VMAT plan it is more complex and time consuming than those conventional treatment modalities, such as intensity modulated radiation therapy. To improve the efficiency and accuracy of its quality assurance procedure, a novel automated anomaly detection method was proposed.
View Article and Find Full Text PDFJ Am Chem Soc
January 2025
Max Planck Institute for Medical Research, Jahnstr. 29, Heidelberg 69120, Germany.
Orange carotenoid protein (OCP) is a photoactive protein that mediates photoprotection in cyanobacteria. OCP binds different ketocarotenoid chromophores such as echinenone (ECN), 3'- hydroxyechinenone (hECN), and canthaxanthin (CAN). In the dark, OCP is in an inactive orange form known as OCP; upon illumination, a red active state is formed, referred to as OCP, that can interact with the phycobilisome.
View Article and Find Full Text PDFPhys Med
January 2025
The Henryk Niewodniczański Institute of Nuclear Physics Polish Academy of Sciences, Cyclotron Centre Bronowice, Krakow, Poland.
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View Article and Find Full Text PDFTumour 'bulk' has historically been considered an important prognostic marker and clinical tool to guide treatment in patients with lymphoma. However, its use and definitions in trial designs varies significantly and it is unclear how this has influenced the relevance of bulk in contemporary practice. This comprehensive literature review evaluated the definitions, applications and prognostic impact of bulk in phase 3 randomised trials in four major lymphoma subtypes.
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