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Background: Hemangiomas are benign noncancerous vascular malformations of capillaries, commonly situated on the face. All laser types are effective for the treatment of such vascular lesions. The study aimed to evaluate the effectiveness of a 980-nm laser diode for treatment of facial hemangioma in Iraqi patients. Method: In an academic, government clinic, uni-center, randomized within patients trial study of the effects of 980-nm diode laser treatment included 15 cases of facial hemangiomas in patients with a history of discomfort due to lesions that were not suitable for removal using traditional methods. The study was carried out at the University of Baghdad/Institute of Laser for Postgraduate Studies/Laser Medicine Research Clinics from 15 October 2018 to 15 April 2019. Primary end-point is improvement of conditions at 6 months. Secondary end-points are quality of life, disappear lesions and safety administration of diode laser. Each patient received 12 sessions at two-week intervals. Lesions were photographed before and after laser treatment and digital image histograms were generated as a graphical representation of the tonal distribution. Results: Following treatment, the lesions were less elevated, smoother in texture, and the color changed from dark red to light pink. Conclusion: There is a need to improve the treatment of face hemangiomas. Results from this randomized within patient trial will serve as preliminary evidence of the future role of diode laser in hemangioma treatment and a basis for design and power estimations of future studies. Based on the skin texture, color and elevation of the hemangioma as well as patient satisfaction, this type of laser is a safe and effective modality for the treatment of facial hemangioma in Iraqi patients.

We report on the diverse pulsed operation regimes of a femtosecond-laser-written Yb:KLuW channel waveguide laser emitting near 1040 nm. By the precise position tuning of a carbon-nanotube-coated saturable absorber (SA) mirror, the transition of the pulsed operation from Q-switching, Q-switched mode-locking and finally sub-GHz continuous-wave mode-locking are obtained based on the interplay of dispersion and mode area control. The Q-switched pulses exhibit typical fast SA Q-switched pulse characteristics depending on absorbed pump powers. In the Q-switched mode-locking, amplitude modulations of the mode-locked pulses on the Q-switched envelope are observed. The radio-frequency spectrum represents the coexistence of Q-switching and mode-locking signals. In the purely mode-locked operation, the waveguide laser generates 2.05-ps pulses at 0.5 GHz. ; National Research Foundation of Korea (2018H1A2AA1061480, 2019R1A2C3003504, 2020R1A4A2002828); Spanish Government (FIS2017-87970-R, MAT2016-75716-C2-1-R (AEI/FEDER,UE)); Junta de Castilla y León (SA287P18); Generalitat de Catalunya (2017SGR755).

[Full-text paper not available yet] ; The dynamics and the reactivity of the plasma produced during pulsed laser ablation of LiNbO3 have been investigated. Optical emission spectroscopy combined with time-gated imaging with high spatial resolution is applied to the study of the factors that influence the plasma expansion process, the dynamics of the ejected species the influence of a background atmosphere (O2 and Ar) and the reactivity of the expanding plasma. Direct evidence for O2 dissociation occurring during expansion is presented and the temporal evolution of the spatial distribution of the dissociated O2 is studied in detail. The influence of dissociation and velocities of the ablated species on the quality of thin films grown by pulsed laser deposition are discussed. ; This work was partially funded by CICYT (Spain), under Project No. TIC 2002-03235 and by European Union under Project No. HPRN-CT-2002-00328. ; Peer reviewed

Granite has been widely used as a structural and ornamental element in public works and buildings. In damp climates it is almost permanently humid and its exterior surfaces are consequently biologically colonized and blackened We describe a comparative analysis of the performance of two different laser sources in removing biological crusts from granite surfaces: nanosecond Nd:YVO4 laser (355 nm) and femtosecond Ti:Sapphire laser at its fundamental wavelength (790 nm) and second harmonic (395 nm). The granite surface was analyzed using scanning electron microscopy, attenuated total reflection – Fourier transform infrared spectroscopy and profilometry, in order to assess the degree of cleaning and to characterize possible morphological and chemical changes caused by the laser sources. ; This work is supported by the CTM2010-19584, FIS2009-09522 and CSD2007-00013 research projects (Ministerio de Ciencia y Tecnología, Spanish Government) and by SA086A12-2 project (Junta de Castilla y León, Spain). FTIR, profilometry and SEM analyses were conducted at the University of Vigo's research centre (CACTI).

AbstractThis work presents a combined optical and magneto‐optical spectroscopic study of thulium iron garnet (Tm3Fe5O12, TmIG) films on substituted gadolinium gallium garnet (Gd2.6Ca0.4Ga4.1Mg0.25Zr0.65O12, sGGG) substrates. Spectroscopic ellipsometry, transmission spectroscopy, magneto‐optical Kerr effect spectroscopy and Raman spectroscopy results are presented for TmIG films with a thickness in the range from 20 to 300 nm grown on sGGG by pulsed laser deposition. The complex dielectric functions of TmIG and sGGG are determined and compared with previously published results for bulk yttrium iron garnet and GGG, respectively. The magneto‐optical spectroscopy corroborated with Raman spectroscopy sheds light on strain‐induced changes as a function of TmIG film thickness.