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Metallic copper Cu and bimetallic copper–silver CuAg nanoparticles (NPs) are generated by the ablation of copper bulk target in water and aqueous Ag colloidal solution, respectively. The experiments were performed using nanosecond Nd:YAG laser operating at 1064 nm. The generated NPs are characterized by UV–vis absorption spectroscopy, laser-induced breakdown spectroscopy, dynamic light scattering and scanning electron microscopy. The conducted investigations can be summarized as follows: (i) CuAg NPs colloidal solution possess the absorption in UV–vis spectral region, which can be attributed to the Cu-component; (ii) the primary bimetallic CuAg NPs have near uniform dimensions with diameter of about 15 nm, and as a rule, they are grouped into larger agglomerates without defined morphology; (iii) the obtained Cu NPs have mainly spherical form with average diameters up to 20 nm. Both types of NPs show a tendency towards the formation of large agglomerates with different morphology. Bimetallic NPs show the plasmon resonance in the vicinity of 640 nm with a good coincidence with formation of the colloidal solution of pure Cu NPs. The results also demonstrate that the core–shell structure (Ag-rich core/Cu-rich shell) is important for the formation of the bimetallic NPs, also agreeing very well with theory. [ABSTRACT FROM AUTHOR]

A study of morphological and composition changes of the WTi/Si system induced by nanosecond and picosecond laser pulses is presented. A 190 nm thick WTi film was deposited on a silicon substrate of n-type (100). The pulsed laser systems used were: nanosecond TEA CO2 laser (emission, 10.6 um; pulse FWHM; pulse duration 120 ns) and picosecond Nd:YAG laser (emission, 532 nm; pulse FWHM; pulse duration 40 ps). During experiments the used fluences (Ph) had similar values, Ph1 = 20 J cm [?] 2 in case of the TEA CO2 laser and Ph2 = 16 J cm [?] 2 for the Nd:YAG laser. The laser-induced morphological and composition modifications showed a dependence on pulse duration. Generally, the following morphological changes were observed: (i) ablation/exfoliation of the WTi thin film, (ii) appearance of hydrodynamic features such as resolidified material, and (iii) formation of nano-sized grains and globules. Overall morphological modifications were more pronounced after the picosecond laser action. The surface composition analysis showed a quite different distribution of sample components depending on the pulse duration. Formation of the silicon dioxide (SiO2) was recorded only in the case of irradiation of the WTi/Si system by picosecond laser pulses. [ABSTRACT FROM AUTHOR]

Introduction: Erythrocyte indices LHD and Maf are complementary parameters to complete blood count and have been shown as reliable iron deficiency markers in different clinical settings. The aim of the study was to assess diagnostic performances of LHD and Maf in detecting iron deficiency in nonanaemic stable COPD patients., Methods: A total of 93 nonanaemic stable COPD patients were classified as either iron deficient (ID, N = 15) or non-iron deficient (non-ID, N = 78). Iron deficiency was defined as a ferritin level < 100 μg/L with a transferrin saturation (TSAT) <20%. A complete blood count, including LHD and Maf as well as other relevant inflammation and iron status parameters were obtained for all participants., Results: Both LHD and Maf have shown significant differences between the ID and non-ID group with p = .003 and p = .007 respectively. The AUC for LHD was .744 (95% CI: .626-.863, p = .003) with the best cut-off of 5.85 and sensitivity of 80% (95% CI: 76.0-84.0) and specificity of 61.5% (95% CI: 58.4-64.6). The AUC for Maf was .707 with optimal cut-off value 12.65 and sensitivity of 83.3% (95% CI: 79.1-87.5) and specificity of 60.0% (95% CI: 57.0-63.0). Furthermore, LHD performance was not affected by vitamin B12 status., Conclusion: LHD and Maf are useful for iron deficiency diagnosis in stable COPD patients. LHD was shown to be resistant to vitamin B12 deficiency, which is of substantial importance in specific patient subpopulations. Both parameters are not technology-dependant and do not require additional sample and/or reagent volume, which makes them cost-effective and convenient for everyday use., (© 2023 John Wiley & Sons Ltd.)

In this work we present biological effects of silver nanoparticles (AgNPs) synthesized by picosecond laser ablation of silver in deionized water. We examined induction of chromosomal aberrations, lymphocyte micronuclei, appearance and recovery of double strand breaks (DSBs) of DNA, cell proliferation potential, concentration of lipid peroxidation products and insulin-like growth factor 1 (ILGF-1). We found that AgNPs sized from 3 nm to 8 nm induce cell cytostasis, which is accompanied with its clastogenic action on DNA, while AgNPs, sized 2 nm behaves contrary stimulating cell proliferation by enhancing ILGF-1 concentration., (Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.)

Spatially resolved, time-integrated optical emission spectroscopy was applied for investigation of copper plasma produced by a nanosecond infrared (IR) transversely excited atmospheric (TEA) CO2 laser, operating at 10.6 μm. The effect of surrounding air pressure, in the pressure range 0.1 to 1013 mbar, on plasma formation and its characteristics was investigated. A linear dependence of intensity threshold for plasma formation on logarithm of air pressure was found. Lowering of the air pressure reduces the extent of gas breakdown, enabling better laser-target coupling and thus increases ablation. Optimum air pressure for target plasma formation was 0.1 mbar. Under that pressure, the induced plasma consisted of two clearly distinguished and spatially separated regions. The maximum intensity of emission, with sharp and well-resolved spectral lines and negligibly low background emission, was obtained from a plasma zone 8 mm from the target surface. The estimated excitation temperature in this zone was around 7000 K. The favorable signal to background ratio obtained in this plasma region indicates possible analytical application of TEA CO2 laser produced copper plasma. Detection limits of trace elements present in the Cu sample were on the order of 10 ppm (parts per million). Time-resolved measurements of spatially selected plasma zones were used to find a correlation between the observed spatial position and time delay.