We explore the use of a fast laser melting simulation approach combined with atomistic molecular dynamics simulations in order to determine the melting and healing responses of B-DNA and Z-DNA dodecamers with the same d(5'-CGCGCGCGCGCG-3')2 sequence. The frequency of the laser pulse is specifically tuned to disrupt Watson-Crick hydrogen bonds, thus inducing melting of the DNA duplexes. Subsequently, the structures relax and partially refold, depending on the field strength. In addition to the inherent interest of the nonequilibrium melting process, we propose that fast melting by an infrared laser pulse could be used as a technique for a fast comparison of relative stabilities of same-sequence oligonucleotides with different secondary structures with full atomistic detail of the structures and solvent. This could be particularly useful for nonstandard secondary structures involving non-canonical base pairs, mismatches, etc.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1063/1.4945340 | DOI Listing |
Sci Adv
January 2025
James Watt School of Engineering, University of Glasgow, Glasgow G12 8QQ, UK.
The time-resolved detection of mid- to far-infrared electric fields absorbed and emitted by molecules is among the most sensitive spectroscopic approaches and has the potential to transform sensing in fields such as security screening, quality control, and medical diagnostics. However, the sensitivity of the standard detection approach, which relies on encoding the far-infrared electric field into amplitude modulation of a visible or near-infrared probe laser pulse, is limited by the shot noise of the latter. This constraint cannot be overcome without using a quantum resource.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
January 2025
Faculty of Technical Chemistry, Institute of Chemical Technologies and Analytics, Technische Universität Wien, Vienna 1060, Austria.
Atomic force microscopy-infrared spectroscopy (AFM-IR) is a photothermal scanning probe technique that combines nanoscale spatial resolution with the chemical analysis capability of mid-infrared spectroscopy. Using this hybrid technique, chemical identification down to the single molecule level has been demonstrated. However, the mechanism at the heart of AFM-IR, the transduction of local photothermal heating to cantilever deflection, is still not fully understood.
View Article and Find Full Text PDFLasers Med Sci
January 2025
Aalborg University Hospital, Aalborg, Denmark.
Hemangiomas are common benign vascular tumors that often present in childhood. The 595 nm pulsed dye laser (PDL) is now being widely used to treat vascular skin lesions. This case series was performed to review the therapeutic efficacy and safety of PDL in the treatment of hemangiomas among Vietnamese patients.
View Article and Find Full Text PDFNanomaterials (Basel)
January 2025
Key Laboratory of Organic Integrated Circuit, Tianjin Key Laboratory of Molecular Optoelectronic Sciences & Ministry of Education, Department of Chemistry, School of Science, Tianjin University, Tianjin 300072, China.
The exploitation of high-performance third-order nonlinear optical (NLO) materials that have a favorable optical limit (OL) threshold is essential due to a rise in the application of ultra-intense lasers. In this study, a Cu-based MOF (denoted as Cu-bpy) was synthesized, and its third-order NLO and OL properties were investigated using the Z-scan technique with the nanosecond laser pulse excitation set at 532 nm. The Cu-bpy exhibits a typical rate of reverse saturable absorption (RSA) with a third-order nonlinear absorption coefficient of 100 cm GW and a favorable OL threshold of 0.
View Article and Find Full Text PDFPhotoacoustics
February 2025
School of Biomedical Engineering, Southern Medical University, Guangzhou, Guangdong 510515, China.
Photoacoustic tomography (PAT) enables non-invasive cross-sectional imaging of biological tissues, but it fails to map the spatial variation of speed-of-sound (SOS) within tissues. While SOS is intimately linked to density and elastic modulus of tissues, the imaging of SOS distribution serves as a complementary imaging modality to PAT. Moreover, an accurate SOS map can be leveraged to correct for PAT image degradation arising from acoustic heterogeneities.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!