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Over the past six decades, dye laser technology has improved substantially. The usage of solid matrices containing laser dyes is becoming more and more popular as a viable substitute for the traditional liquid dye solutions. In this research, we designed and built a tunable solid dye laser device which consists of three main parts. (i) The active material producing the laser beam, which is a polymer rod [glycidyl methacrylate (GMA) polymer] doped with the laser dyes pyrromethene 597 (PM-597) or Nile blue (Nb-690). (ii) The pumping source is xenon linear flashlamp driven by a homemade power supply. (iii) Two broadband mirrors providing the optical feedback stable optical resonator. The properties of the gain medium and hence the laser emission characteristics were determined, and the results showed the efficiency of the homemade tunable solid dye laser device, that is suitable for a variety of applications. [ABSTRACT FROM AUTHOR]

Localized scleroderma (LS), commonly known as morphea, presents a significant clinical challenge due to its chronic, inflammatory nature affecting the skin and potentially underlying tissues. This systematic review explores the innovative approach of combining laser therapy and injectable fillers, specifically hyaluronic acid, for the treatment of LS. We conducted a comprehensive literature review following PRISMA guidelines, examining articles from MEDLINE/PubMed to assess the combined efficacy of these treatments in improving both esthetic and functional outcomes for LS patients. The search yielded 64 articles, with six selected for in-depth analysis for a total of nine patients, covering a range of patient demographics and treatment types. Our review highlights cases where fractional CO2 laser therapy promoted long-term tissue remodeling and instances where hyaluronic acid fillers effectively addressed skin atrophy and volume loss, enhancing both immediate and long-lasting esthetic improvements. The synergy between these treatments suggests a promising dual approach, aiming to maximize esthetic outcomes and to improve the quality of life for LS patients. This review underscores the necessity of further research to establish a comprehensive, evidence-based clinical pathway integrating both treatments for managing LS, thereby enhancing patient satisfaction and addressing the multifaceted nature of this challenging dermatological condition. [ABSTRACT FROM AUTHOR]

We report an investigation of a semiconductor disk laser (SDL) based on an InGaP/AlGaInP heterostructure emitting at a wavelength near 640 nm under in-well pumping by a pulsed rhodamine 6G dye laser with an emission wavelength of 601 nm. Use is made of structures with 25 quantum wells arranged in depth with a period of 193 nm. In a structure with a built-in Bragg mirror, a power of 3.5 W is reached at a wavelength of 642 nm with a slope efficiency of 7% with respect to the absorbed pump power. The achieved second harmonic power at a wavelength of 321 nm is approximately 30% of the maximum SDL power at the fundamental frequency. Under pumping above 250 W, the structure is destroyed due to strong adiabatic heating of the GaAs growth substrate. In a structure with a deposited broadband dielectric mirror, it is possible to reduce the adiabatic heating factor, implement double-pass pumping, and, accordingly, increase the supplied pump power. This makes it possible to obtain a pulse power of higher than 70 W at a wavelength of 645.5 nm with a slope efficiency of over 17%. [ABSTRACT FROM AUTHOR]

The Birt-Hogg-Dubé Syndrome (BHDs) can cause benign skin lesions like fibrofolliculomas as well as additional systemic symptoms like pulmonary cysts, kidney tumors, and recurrent pneumothoraces. We report the successful treatment of fibrofolliculomas in a patient with BHDs using a combination of fractionated ablative CO2 laser and a Flash Lamp Pulsed Dye Laser (FPDL). This combined method improves the CO2 healing process's functional and cosmetic results; while the first wavelength (ablative) has a greater capacity for excision and tissue regeneration, the second wavelength (non-ablative) provides more control over the tissue healing process. The lesions were successfully ablated up to the papillary dermis without leading to an enhancement in the overall textural appearance. Therefore, deeper laser ablations may be able to stop dermal residual lesion relapses. In conclusion, fractionated CO2 laser and FPDL can be used safely and effectively to reduce the appearance of facial hamartomas related to BHDs.

In this study, gold nanoparticle samples were prepared by the chemical reduction method (seed-growth) with 4 ratios (10, 12, 15 and 18) ml of seed, and the growth was stationary at 40 ml. The optical and structural properties of these samples were studied. The 18 ml seed sample showed the highest absorbance. The X- ray diffraction (XRD) patterns of these samples showed clear peaks at (38.25o, 44.5o, 64.4o, and 77.95o). The UV-visible showed that the absorbance of all the samples was in the same range as the standard AuNPs. The field emission-scanning electron microscope (FE-SEM) showed the shape of AuNPs as nanorods and the particle size between 30-50 nm. Rhodamine-610 (RhB) was prepared at 10-5 M concentration, the optical measurements were studied, AuNPs and RhB were mixed at ratios (1:1, 1:2, 1:3), and the fluorescence measurements were done. Full width at half maximum (FHWM) and the intensity of RhB after mixing were changed, and this result showed significant efficacy for many applications. The study shows that this mixing could be used after doping with polymer as a random gain medium or saturation absorber for pulse laser generation.

Introduction: The Flash‐lamp pulsed dye laser (FPDL) is nowadays considered the most precise laser currently on the market for treating superficial vascular lesions. In this study, we gathered data from 10 years of experience regarding dye laser treatment of patients presenting vascular malformations such as telangiectasia, rhinophyma, port‐wine stain, cherry and spider angioma and vascular tumours. Methods: Subjects were enrolled from 2013 to 2023 based on the vascular anomalies they presented. They underwent different treatment sessions with the FPDL device. Results: The age‐range distribution by vascular anomaly confirmed that haemangiomas are typical in children while rhinophyma is a condition very common in older adults. A difference in sex distribution showed that pathologies such as telangiectasias typically affect women whereas rhinophyma is more frequent in men. Most of the treatments interested the face area but no permanent side effects were registered. Conclusions: Our 10 years of experience with FPDL demonstrated good results in a wide range of applications for the treatment of different vascular anomalies. The absence of long‐term side effects and bearable pain during the treatment makes it a valuable solution for the resolution of benign tumours also in very young patients. [ABSTRACT FROM AUTHOR]

Copyright of Iraqi Journal of Physics is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Port-wine stains (PWS) are frequently refractory to laser treatments. The aim of this study is to evaluate the role of treatment interval time. From 1990, 216 patients underwent Pulsed Dye Laser sessions. The laser sessions were scheduled at a minimum interval of 4 weeks to a maximum of 48 weeks. Clinical outcomes were assessed 8 weeks after the last laser session. Better results were obtained with 8 weeks interval time between therapy session, and high efficacies were also found for intervals of 4, 6 and 10 weeks. For greater interval instead, the effectiveness is significantly lower. [ABSTRACT FROM AUTHOR]

Artificial red blood cells [i.e., hemoglobin vesicles (HbVs)] can be used as photosensitizers in pulsed-dye laser (PDL) treatment for port wine stains in animal models. Small HbVs are distributed in the vicinity of the endothelial cells of the blood vessels. In our previous in vivo experiments, both HbVs and red blood cells absorbed photons of the laser and generated heat, contributing to removal of very small blood vessels and large deeper subcutaneous blood vessels with PDL irradiation. Herein, we tested carbon monoxide-bound HbVs (CO-HbVs) that would produce heat energy while releasing CO in vessels after dye laser irradiation in a rabbit auricle model. We conducted this experiment to confirm secondary progression of thermal injury being reduced with the antioxidative property of CO. We histopathologically evaluated the damages to the large vessels and surrounding dermal tissue following PDL irradiation alone or subsequent to the intravenous injection of the qualified HbVs. The soft tissue damages were graded on a five-point scale and compared statistically. Intravenous CO-HbVs significantly reduced damage to the surrounding tissue after subsequent PDL irradiation; however, the degree of damage to the larger vessel wall resulted in a variety of changes, including a slight increase in our histopathological grades. This beneficial effect in dye laser treatment for port wine stains may be the result of the antioxidative property of CO against free radicals in the zone of stasis that may still be theoretically viable in burns. This effect of CO protecting tissues from thermal damage is consistent with previous reports of CO as a reducing agent. If the reducing agent can be delivered directly to the affected area immediately after the burn injury, even in a small amount, the complex inflammatory cascade may be reduced and unnecessary inflammation after laser treatment that lowers the patient's quality of life can be avoided. [Display omitted] • CO-bound artificial red blood cells reduced thermal damage by dye laser irradiation. • Antioxidants delivering directly to the affected area immediately after a burn. • Even in a small amount, it can reduce the secondary burn progression. [ABSTRACT FROM AUTHOR]

The processes of resonant interaction of short pulses of dye laser polychromatic radiation with plasma of a nanosecond discharge in neon with an extended hollow cathode are experimentally studied. Dispersion-type asymmetric optical transmission spectra of the plasma near the spectral absorption line of Ne I with a wavelength of 650.6 nm are detected during propagation of the laser radiation inside the cathode cavity while classical symmetric transmission spectra are formed during propagation of the laser radiation in the region between the electrodes. [ABSTRACT FROM AUTHOR]

Liquid dye lasers are intrinsically suitable for high-average-power operation because their flowing laser gain media can effectively remove the heat produced by laser amplification; thus, liquid dye lasers have a significant place in various laser applications. However, to sufficiently remove the dye solution heated by the laser, a very cumbersome dye flow system is required to achieve a high flow velocity in the dye cell of a high-power dye laser, which limits its applications. In this paper, we found that the pressure and power required to drive the high-speed dye flow are both proportional to the square of the laser beam size along the direction of the flow. Based on this result, we proposed a novel longitudinal pumping scheme that uses elliptical laser beams. This new scheme can significantly reduce the size and energy consumption of dye flow loops in high-power dye lasers. We also developed a dye laser system with a main amplifier using a 1 mm × 4 mm elliptical input laser beam. The amplifier produced an average power of 135 W with a repetition rate of 10 kHz and a conversion efficiency of 39.5%. The M 2 factor of the output beam was better than 1.7. The flow parameters to drive the dye flow loops were 2. 1 × 1 0 5 Pa, and 0.43 L/s, which gave a clearing ratio of 2 for the amplifier. This new pumping scheme enables high-power dye lasers to be more compact and efficient, making them more flexible for various applications. • The relationship between dye flow pressure and laser beam dimensions is investigated for the first time. • A new longitudinal pumping scheme is proposed and experimentally demonstrated. • Achieve an average output power of 135 W at a beam quality M 2 < 1. 7 [ABSTRACT FROM AUTHOR]

Covalent bonding between the Rhodamine B xanthene dye and polyurethanes, containing different isocyanate fragments (hexamethylene diisocyanate and toluene diisocyanate) has been realized and studied. Effects of polyurethane isocyanate components, different by chemical structure, on spectral properties of the Rhodamine B have been studied and discussed. Spectral, photophysical and lasing characteristics of the Rhodamine B dye, incorporated to the polyurethane matrices are presented. [ABSTRACT FROM AUTHOR]

We investigate the effects of 10.6 μm CO2 laser irradiation and 572 nm dye laser irradiation on optical properties and laser damage threshold of Nd:glass. We study the transmission, additional absorption (AA) spectra, and damage threshold of the samples before and after the irradiation. The results obtained indicate that irradiation of Nd:glass by pulsed CO2 and dye lasers is extremely effective for decrease of defects and increase in damage thresholds. The damage threshold of Nd:glass increases by a factor of 4.13 for dye laser and a factor of 3.1 for CO2 laser. [ABSTRACT FROM AUTHOR]

This paper presents an experimental study on the effect of the pump energy and flow rate of the dye gain medium and one amplifier stage on the linewidth in a dye laser pumped by a frequency-doubled Q-switched Nd:YAG laser. A Fabry-Pérot etalon and imaging camera-based arrangement interfaced with a personal computer (PC) is used to measure the linewidth of the 565 nm laser line. [ABSTRACT FROM AUTHOR]

Background and Objectives: Warts are benign lesions of viral etiology characterized by a hyperkeratotic appearance tending to spread across the skin surface. Various treatments have been proposed to manage this condition, such as acids, imiquimod, photodynamic therapy, cryotherapy, and various lasers. Materials and Methods: In this paper, we describe a combination protocol using CO2 laser prior to Nd:YAG laser for lesions interesting the palmoplantar areas or dye laser for lesions on other skin surfaces in the management of non-facial warts resistant to traditional therapies. In total, 34 patients with 103 warts suffering from wart infection resistant to traditional therapies treated from 1 January 2019 to 1 June 2020 were retrospectively enrolled at the Dermatological Unit of Magna Graecia University (Catanzaro, Italy). Two dermatologists measured clinical results, classifying lesions with complete resolution, partial resolution, or non-responding. Patients at four months follow-up were asked to evaluate their degree of satisfaction with a visual analog scale (VAS). Results: Almost all patients reported the complete resolution of lesions, with no patient reporting scarring. Five patients reported hypopigmentation in the treated areas. The mean satisfaction level was high. Only three patients experienced a relapse of the condition. Conclusions: Using a vascular laser following a CO2 superficial ablation of warts may help reduce the risk of scarring and decrease the incidence of relapses for lesions resistant to traditional therapies. Therefore, more extensive studies will be necessary to confirm the obtained results.

[Display omitted] • Safer, simpler and inexpensive synthesis of 2,4,6-triphenylpyrylium chloride (PyCl) via pseudobase. • PyCl dissolves in common solvents, such as, acetonitrile, ethanol, methanol, dichloromethane and the solutions are stable. • Solutions absorb strongly in the near-ultraviolet and emit efficiently in the blue-green spectral range, with a high absolute quantum yield of 0.84 in acetonitrile. • It showed stimulated emission and laser action in acetonitrile, methanol and ethanol with best performance in acetonitrile. • Two-photon excitation induced fluorescence from PyCl solutions is indicative of its potential application in high-resolution nonlinear optical microscopy and biomedical imaging. The synthesis, optical spectroscopic properties, and lasing potential of 2,4,6-triphenylpyrylium chloride (PyCl) are reported. The synthesis involves conversion of Py-tosylate (instead of commonly used Py-perchlorate) to a pseudo-base, which is then transformed to PyCl by reacting with HCl. Solutions of the salt in different solvents absorb in the blue-near ultraviolet and emit in the blue-green spectral ranges with fluorescence quantum yield of 0.84 in acetonitrile. Under intense ultrashort laser pumping, salt solutions in acetonitrile, ethanol and methanol demonstrated stimulated emission and laser action with nominal feedback. Two-photon excited fluorescence was also observed. [ABSTRACT FROM AUTHOR]

Background and Objectives: Warts are benign lesions of viral etiology characterized by a hyperkeratotic appearance tending to spread across the skin surface. Various treatments have been proposed to manage this condition, such as acids, imiquimod, photodynamic therapy, cryotherapy, and various lasers. Materials and Methods: In this paper, we describe a combination protocol using CO2 laser prior to Nd:YAG laser for lesions interesting the palmoplantar areas or dye laser for lesions on other skin surfaces in the management of non-facial warts resistant to traditional therapies. In total, 34 patients with 103 warts suffering from wart infection resistant to traditional therapies treated from 1 January 2019 to 1 June 2020 were retrospectively enrolled at the Dermatological Unit of Magna Graecia University (Catanzaro, Italy). Two dermatologists measured clinical results, classifying lesions with complete resolution, partial resolution, or non-responding. Patients at four months follow-up were asked to evaluate their degree of satisfaction with a visual analog scale (VAS). Results: Almost all patients reported the complete resolution of lesions, with no patient reporting scarring. Five patients reported hypopigmentation in the treated areas. The mean satisfaction level was high. Only three patients experienced a relapse of the condition. Conclusions: Using a vascular laser following a CO2 superficial ablation of warts may help reduce the risk of scarring and decrease the incidence of relapses for lesions resistant to traditional therapies. Therefore, more extensive studies will be necessary to confirm the obtained results. [ABSTRACT FROM AUTHOR]

• Covalent bonding between a cyanine dye and a polyurethane has been realized directly. • The dye-polymer covalent bonding improves considerably photophysics of the dye molecules. • Polyurethane material, synthesized by polycondensation, provides improved laser characteristics. Spectral, photophysical and generation properties of symmetrical cationic cyanine dyes have been investigated in the polyurethane matrices, similar by the structure, but different by the polymerization method. The cyanine dye doped polyurethane, synthesized by a polycondensation reaction, provides laser active elements with significantly improved photostability, efficiency and operation lifetime, compared to those for the polyurethane acrylate matrix, hardened by a radical photopolymerization method. Changing the liquid (ethanol) medium to polymers causes an increase of fluorescence quantum yield and efficiency. For the first time, covalent bonding between a cyanine dye and a polyurethane has been studied, and high fluorescence quantum yield and generation efficiency have been observed. [ABSTRACT FROM AUTHOR]