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Purpose: To measure the surface temperature distribution after using a CO2 laser to heat titanium dental implants via different power settings, application intervals, and irradiation times. Materials and Methods: A total of 10 tissue-level titanium implants (Screw-Line Promote Plus, Camlog; 4.3 × 11 mm) were placed (EpoFix, Struers) and irradiated with a CO2 laser (Denta 2, Lutronic) with a wavelength of 10.6 µm at power levels of 4 watts (Group 1), 6 watts (Group 2), 8 watts (Group 3), and 10 watts (Group 4). A continuous beam mode (setting I) and noncontinuous beam modes with 5-second (setting II) and 10-second (setting III) pause intervals were used. For each setting, a total irradiation time of 50 seconds was used and repeated 10 times. The temperature was measured using external thermocouple (Testo) in contact with the implant surface at the implant shoulder, middle, and apex. A linear regression model was used to analyze the data (P = .05). Results: Setting I demonstrated the most rapid increase in implant surface temperature in all three test sites as well as the greatest total temperature at 50 seconds of irradiation time. The greater the pause interval (settings II and III) during the 50 seconds of irradiation, the lower the rate of temperature increase as well as the total temperature in all three test sites and with all power levels. The average temperature difference between the apex and shoulder site was significant for setting III for all groups, but not for any groups in settings I and II. Conclusions: Heating the internal aspect of an implant with a CO2 laser produces different temperature distribution profiles depending on the laser power level and the application interval. Laser-beam irradiation leads to a temperature gradient, which is greatest at the implant apex and smallest at the implant shoulder. [ABSTRACT FROM AUTHOR]

Objective: Photobiomodulation therapy is recommended by multiple international societies for managing oral mucositis. These recommendations are based on extensive evidence. However, the search for an optimal photobiomodulation protocol continues. This mapping review focuses on a novel aspect of photobiomodulation therapy which is the immediate effect on pain levels associated with oral ulcerative conditions. Data sources: This literature review systematically compiles and evaluates the evidence about oral mucositis, alongside other oral ulcerative conditions, as the protocols that achieved pain relief for these oral conditions may have potential applicability to oral mucositis management. The scientific database used was PubMed. Conclusion: Whereas most of the randomized controlled trials about photobiomodulation therapy for oral mucositis and other ulcerative oral diseases reported delayed pain relief, certain photobiomodulation therapy protocols reported immediate pain relief. The results of this review highlight the concept of preemptive photobiomodulation therapy, in which photobiomodulation therapy is delivered early in the development of oral mucositis throughout the oncotherapy and may achieve immediate pain relief consistently in most of the patients and close to a negligible pain level. Photobiomodulation therapy, as a powerful nonpharmacologic tool for immediate pain relief, has a great beneficial value in patients suffering from oral mucositis and other painful oral ulcerative diseases such as recurrent aphthous stomatitis and chronic graft-versus-host disease. [ABSTRACT FROM AUTHOR]

Due to working in static positions and use of repetitive movements over long periods of time, dermatologists are at increased risk of work-related musculoskeletal injury. Historically, studies on procedural ergonomics have focused on dermatologic surgery, however, laser procedures can also have a significant cumulative effect on physician posture. Here, we aim to highlight ergonomic challenges specific to dermatologic laser procedures and suggest areas of improvement in operating room organization, patient positioning, physician mechanics, and instrumentation. For the operating room, it is beneficial to store several devices in the same room, have central placement of electrical outlets, and to position the devices on the same side of the bed as the laser operator. When considering patient positioning, a Trendelenburg bed position can be helpful for vascular lesions on the head, and frequent repositioning of the patient can prevent uncomfortable bending of the operator and laser arm for circumferential lesions. Physicians should maintain a working position with a neutral spine and wrist position, moving the patient and bed as needed to reduce muscle tension. Lastly, laser instrumentation in the future could be improved upon with lightweight consoles and hand pieces, long multi-articulated device arms, and lightweight laser goggles with adjustable head straps. With the use of organizational, ergonomic positioning, and teamwork strategies, we can reduce the risk of musculoskeletal injury for our laser operators.

Attosecond science requires a substantial rethinking of how to make measurements on very short timescales; how to acquire the necessary equipment, technology, and personnel; and how to build a set of laboratories for such experiments. This entails a rejuvenation of the author in many respects, in the laboratory itself, with regard to students and postdocs, and in generating funding for research. It also brings up questions of what it means to do attosecond science, and the discovery of the power of X-ray spectroscopy itself, which complements the short timescales addressed. The lessons learned, expressed in the meanderings of this autobiographical article, may be of benefit to others who try to reinvent themselves.

A simple and rapid method that is not based on race and ethnicity for classifying people with skin of color is of paramount importance in dermatology. The currently used Fitzpatrick classification of sun-reactive skin types is inadequate. Newer scales that have been used in immigration surveys and sociology studies are not applicable in the office setting. A new, non-racial and non-ethnic, colorimetric scale for skin of color has recently been proposed that is simple to perform. The scale has five colors: very light beige (skin color type 1), light brown (skin color type 2), medium brown (skin color type 3), dark brown (skin color type 4) and very dark brown (skin color type 5); an individual with white skin, such as in albinism, would have a skin color type 0 in this classification. In conclusion, the colorimetric scale enables the rapid classification of individuals with skin of color and allows for accurate assessment of skin cancer risk, more appropriate management of cosmetic dermatologic procedures and aesthetic devices, and enhanced ability for focused counseling regarding hair products, skin care interventions, and color-targeted makeup based on the person's skin tone.

This work addresses the challenges in brazing thermohydraulic sealings involving dissimilar materials, specifically 316Ti stainless steel and alumina, which have significantly different coefficients of thermal expansion (CTEs) and elastic constants. Traditional brazing methods require complex interlayers or extensive metallization steps, leading to issues such as dimensional changes, braze voids, and inadequate corrosion resistance due to prolonged high‐temperature exposure. A novel laser‐based brazing technique utilizing a diode laser is introduced to create high‐quality, localized joints while preserving the integrity of the parent materials. The study systematically optimizes laser process parameters using finite‐element modeling and the Taguchi method to achieve the desired bead geometry and thermal stress distribution with minimal heat input. Comparative analysis between laser active brazing (LAB) and conventional furnace brazing was conducted through metallography, shear testing, and autoclave testing. Results indicate that LAB parameters significantly affect bead thickness and shear strength, with laser‐brazed joints demonstrating superior quality and stability post‐autoclave testing compared with furnace‐brazed joints. The thermodynamic and kinetic aspects of the brazing process were also analyzed. In conclusion, the LAB method for brazing 316Ti to alumina proves to be a successful and efficient alternative, with joint properties meeting or exceeding those of traditional furnace brazing. [ABSTRACT FROM AUTHOR]

AbstractJoining copper with stainless steel (SS) is essential due to their complementary properties. Copper’s excellent thermal conductivity and SS’s robustness and high mechanical strength create joints that manage heat effectively and maintain structural integrity. This combination is particularly beneficial in heat exchangers, fusion reactors, electronics, batteries, chemical processing, and nuclear engineering, where efficient heat management and corrosion resistance are critical. However, the heterogeneous nature of these materials presents challenges such as differing melting points and thermal expansion coefficients. Deep understanding of metallurgical processes is needed to overcome these issues. Successfully joining copper and SS via well-established fusion welding processes can lead to innovative industrial solutions, enhancing performance, reliability, and durability across various applications. This article reviews fusion welding techniques for joining copper to SS, highlighting the need for precise parametric optimization. It identifies research gaps and emphasizes innovative welding methods to enhance joint quality, supporting advanced, reliable structural component development. [ABSTRACT FROM AUTHOR]

Background: Androgenetic alopecia (AGA) is a prevalent form of hair loss that affects both men and women, severely impacting patients' quality of life. Traditional treatments include oral medications, topical medications, and hair transplantation, but these methods have certain side effects and limitations. How to safely effectively and maximally promote hair growth has been a key issue in the treatment of AGA. In recent years, fractionated laser therapy, as a noninvasive method, has gradually gained attention due to its minimally invasive and highly effective nature. Aims: In this paper, we summarized the studies related to fractional laser treatment of AGA in the past 15 years, and discussed its therapeutic mechanism, clinical effect, future development direction, and advantages and disadvantages compared with traditional treatment methods in the treatment of AGA. Methods: An extensive literature search was conducted using PubMed, Google, Google Scholar, Embase, and Scopus. All available articles studying fractional laser treatment of AGA were compiled in March 2024. Titles and abstracts were then screened for relevance and thoroughly examined for patient clinical outcomes. Prospective clinical trials, retrospective chart reviews, case series, and individual case reports were included in the literature review. Conclusions: Fractional laser treatment of AGA showed remarkable efficacy and high safety. Compared with traditional treatments, fractional laser has the advantages of minimally invasive, quick recovery, fewer side effects, and a wide range of population applicability, providing an effective treatment option for AGA patients. Further large‐scale clinical studies will help optimize the laser parameters and treatment settings to improve the therapeutic effect. [ABSTRACT FROM AUTHOR]

Purpose: We explored the elicitation role of the laser irradiations on the alleviation of nutrient-deficiency induced damage in anthocyanin-producing red-fleshed apple cell suspension in continuous production of anthocyanin. Methods: Anthocyanin-producing red-fleshed apple cells were irradiated by 4 intensity levels of red He-Ne (RHNL) and blue diode (BDL) lasers for 20 min. Results: Nutrient deficiency indicated negative effect on total soluble proteins (TSP), superoxidase dismutase (SOD) activity, and total phenolics content (TPC) while it displayed a positive effect on malondialdehyde (MDA), total flavonoids content (TFC), O2-, H2O2-, and lipoxygenase (LOX) and polyphenol oxidase (PPO) activities in light controls, illustrating oxidative stress. The laser irradiations on suspension cells indicated variable effects on measured parameters and were time of growth-, levels of intensity-, and laser type-dependent. Likewise, the elicitation effects of lasers relied on a critical threshold among ROS generation and antioxidative system which determines the fate of cells against oxidative stress. The same trend was displayed by RHNL at 6.46 mWcm−2 intensity and BDL at 13.73 mWcm−2. These intensities resulted in a significant increase in SOD, APX, POD, and CAT activities and TSP, TPC, TFC, proline, and glycine betaine accumulation, while induced decrease in LOX, and PPO activities and MDA, and ROS generation, alleviating cellular injury from prolonged nutrient deficiency by diminishing lipid peroxidation and oxidative damages of cell membrane. Conclusion: Results suggested that lasers application on mitigating nutrient deficiency stress relied on establishing a suitable balance between ROS generation and antioxidative system, which enables the nutrient-starved anthocyanin-producing cells to continuously produce anthocyanin. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the safety and efficacy of percutaneous transhepatic endoscopic holmium laser lithotripsy (PTEHL) for patients with intrahepatic bile duct (IHBD) and common bile duct (CBD) stones. Material and methods: This retrospective study included 530 patients (mean age: 55.6 ± 8.5; 64.2% female) with IHBD and/or CBD stones at a single institution from January 2019 to December 2021. PTEHL was the chosen treatment for patients with large, complex stones, or those for whom Endoscopic Retrograde Cholangiopancreatography (ERCP) failed or presented difficulties. Patients showing signs of cholangitis required pre-PTEHL drainage. Stone clearance was confirmed by post-procedural cholangiography, and the technique was deemed successful when target stones were removed. Complications were recorded according to the Society of Interventional Radiology adverse event classification. Results: The mean stone size was 20.9 ± 11.9 mm, multiple stones observed in 460 patients (86.8%). A total of 225 patients (42.5%) had stones in both the IHBD and CBD; biliary-enteric anastomosis in 50 patients (9.4%). ERCP for stone removal proved unsuccessful in 18 patients (3.4%). Pre-IHBD drainage was performed in 271 patients (51.1%). The majority (488 patients, 92.1%) underwent a single PTEHL session. The technique was successful in 523 patients (98.7%), with 7 patients requiring surgery due to unsuccessful target stone removal. Complications were noted in 75 patients (14.2%), including 4.7% with severe complications and 9.4% with minor complications. Conclusion: PTEHL is a safe and effective method for the treatment of both intrahepatic and extrahepatic bile duct stones. This approach is a valuable option for complex stone cases, particularly when ERCP is unsuccessful or encounters significant challenges. Clinical relevance statement: Percutaneous Transhepatic Endoscopic Holmium Laser Lithotripsy is a safe and effective treatment method for intrahepatic and extrahepatic biliary stones, particularly in cases of complex stones. Key Points: Percutaneous transhepatic biliary stone removal is difficult for large or intraductal stones. Percutaneous Transhepatic Endoscopic Holmium Laser Lithotripsy (PTEHL) demonstrated a high success rate with few major complications. PTEHL can treat biliary stones, particularly stones that are difficult or have failed ERCP treatment. [ABSTRACT FROM AUTHOR]

Introduction: This work aims to determine the effect on nerve fiber layer (NFL) and ganglion cell complex (GCC) thickness trends in eyes with open-angle glaucoma (OAG) treated with Vision Protection Therapy™ (VPT). Methods: A retrospective analysis of spectral-domain optical coherence tomography (OCT) measured NFL and GCC thickness trends was performed, excluding eyes with poor-quality scans and principal diagnoses other than OAG. This study compares eyes with OAG managed conventionally with IOP control alone (controls) to eyes managed with the addition of VPT (VPT eyes). The direction (+ or −) and magnitude (microns/year) of the OCT trends were the study endpoints. Results: Seventy-eight control eyes of 40 patients and 61 VPT-treated eyes of 39 patients were included in the study. Positive NFL trends were noted in 5% of control eyes vs. 71% of VPT eyes (p < 0.0001). Positive GCC trends were noted in 8% of control eyes vs. 43% of VPT eyes (p < 0.0001). Mean NFL trends (µm/year) were − 0.692 for controls vs. 0.347 for VPT (p < 0.0001). Mean GCC trends (µm/year) were − 0.554 for controls vs. − 0.148 for VPT (p = 0.0175). Conclusions: The addition of VPT to the conventional management of OAG resulted in highly significant improvements in NFL and GCC trends, indicating a reversal of key indicators of glaucoma severity and progression. [ABSTRACT FROM AUTHOR]

The Laser/PEO ceramic coating was successfully prepared in situ on AZ31B magnesium alloy by laser-assisted PEO (Laser/PEO) composite process. SEM, EDS, CLSM, XRD, XPS and M − S tests were used to observe the effects of different laser power densities on the morphology, chemical composition and electronic properties of PEO ceramic coating. The corrosion behavior of PEO ceramic coating (S0) and Laser/PEO ceramic coating (S1) was systematically observed by PDP test, EIS test, SEM, EDS, XRD and XPS by long-term immersion experiments (24, 96, 168 h) in 3.5 % NaCl solution. Moreover, the effect of laser-assisted irradiation on the corrosion mechanism of PEO ceramic coating was discussed. The Laser/PEO coating (S1) possessed better long-term corrosion resistance than PEO coating (S0), which was attributed to the improvement of laser-assisted irradiation on the density, crystallinity, thickness, and corrosion-resistant phase proportion and distribution of PEO coating. [ABSTRACT FROM AUTHOR]

In this study, we propose a method for detecting feature points of obstacles by real-time processing using a monocular camera and a laser. Specifically, we propose an algorithm that detects laser beams emitted on obstacles by binarization, transforms pixel coordinates into distance using triangulation by a laser beam that is obliquely incident on the ground, and estimates the placement angle of the obstacle in real-time processing. No method has been devised to detect the placement angle of obstacles using a monocular camera and a laser. Furthermore, the proposed method does not calculate the linear distance from the camera, but from the position where the camera is moved horizontally parallel to the obstacle in front of the camera, thus detecting the placement angle independently of the placement position of the obstacle. As a result, it was confirmed that the placement angles of obstacles could be detected with a maximum error of 6 ∘ in six placement positions. Therefore, we succeeded in automatically detecting the placement angle of obstacles in real-time, independent of the illumination of the measurement environment, the reflectance of the obstacle. [ABSTRACT FROM AUTHOR]

Background: There is no objective information reporting the effect of unilateral laser ventriculocordectomy (VeC) on arytenoid abduction or stability. Objectives: To evaluate arytenoid stability and abduction in horses with severe recurrent laryngeal neuropathy (RLN) before and after unilateral laser VeC. Study design: Prospective cohort. Methods: Eight horses with grade C or D exercising laryngeal function that underwent unilateral laser VeC were included. Exercising endoscopy was performed before and ≥6 weeks after left‐sided laser VeC. Arytenoid stability at maximal exercise was calculated by measuring the left‐to‐right quotient angle ratio (LRQ) of the corniculate processes at the points of maximal arytenoid abduction (expiration) and maximal arytenoid collapse (inspiration). For each horse, means of measurements obtained for four breaths pre‐ and post‐operatively were used for statistical analysis. Results: The difference in LRQ between inspiration and expiration was lower post‐operatively (median 0.039; interquartile range [IQR] 0.032–0.047) compared with pre‐operatively (median 0.158; IQR 0.083–0.249; p = 0.01) confirming the left arytenoid was more stable following unilateral laser VeC. The degree of improvement was significantly greater for grade D horses compared with grade C horses (p = 0.04). The LRQ measured on maximal abduction was also lower post‐operatively (median 0.467; IQR 0.444–0.506) compared with pre‐operatively (median 0.578; IQR 0.554–0.655; p = 0.02) indicating the left arytenoid was less abducted following surgery. Main limitations: The sample size was small, no racehorses were included and post‐operative assessment was conducted at a variable time after surgery. Conclusion: Unilateral laser VeC in grade C and D RLN‐affected horses results in slightly reduced left arytenoid abduction but increased arytenoid stability. [ABSTRACT FROM AUTHOR]

Purpose: To compare the accuracy of open-source Artificial Intelligence (AI) Large Language Models (LLM) against human authors to generate a systematic review (SR) on the new pulsed-Thulium:YAG (p-Tm:YAG) laser. Methods: Five manuscripts were compared. The Human-SR on p-Tm:YAG (considered to be the "ground truth") was written by independent certified endourologists with expertise in lasers, accepted in a peer-review pubmed-indexed journal (but not yet available online, and therefore not accessible to the LLMs). The query to the AI LLMs was: "write a systematic review on pulsed-Thulium:YAG laser for lithotripsy" which was submitted to four LLMs (ChatGPT3.5/Vercel/Claude/Mistral-7b). The LLM-SR were uniformed and Human-SR reformatted to fit the general output appearance, to ensure blindness. Nine participants with various levels of endourological expertise (three Clinical Nurse Specialist nurses, Urology Trainees and Consultants) objectively assessed the accuracy of the five SRs using a bespoke 10 "checkpoint" proforma. A subjective assessment was recorded using a composite score including quality (0–10), clarity (0–10) and overall manuscript rank (1–5). Results: The Human-SR was objectively and subjectively more accurate than LLM-SRs (96 ± 7% and 86.8 ± 8.2% respectively; p < 0.001). The LLM-SRs did not significantly differ but ChatGPT3.5 presented greater subjective and objective accuracy scores (62.4 ± 15% and 29 ± 28% respectively; p > 0.05). Quality and clarity assessments were significantly impacted by SR type but not the expertise level (p < 0.001 and > 0.05, respectively). Conclusions: LLM generated data on highly technical topics present a lower accuracy than Key Opinion Leaders. LLMs, especially ChatGPT3.5, with human supervision could improve our practice. [ABSTRACT FROM AUTHOR]

In this paper, the fatigue damage degree of low-alloy structural steel is evaluated by using the attenuation characteristics of laser-induced surface acoustic wave (SAW) during propagation. Taking the typical structural steel material Q345 as an example, a cracks model of fatigue damage is established, and the finite element method is used to solve the model. The results showed that the attenuation coefficient of SAW can reflect the depth and density of fatigue cracks. The surface measurement experiments of specimens with stress cycles of 0, 50000, 100000, 150000, and 200,000 showed that with the increase of stress cycles, the attenuation coefficient of SAW increases as a whole, indicating that it is feasible to evaluate the fatigue damage degree based on the attenuation of SAW. A method of applying tensile stress to the material to improve the sensitivity of fatigue damage evaluation is proposed. The tensile stress is used to offset the horizontal amplitude of the SAW, keeping the fatigue cracks in an open state and increasing the attenuation coefficient of SAW. The attenuation coefficient measurement experiment shows that this method is feasible. [ABSTRACT FROM AUTHOR]

High-performance Ox-Ox ceramics material composites (CMC) are a strategic building block in the aerospace industry and high-temperature applications. The ceramics material composites are hard to machine due to high hardness, fracture toughness, and heterogeneous structures. Furthermore, it is prone to brittle fracture during the machining process. In this study, we successfully demonstrate ultrafast laser machining technology to machine Ox-Ox CMCs. A picosecond laser has been used to machine slots to understand the impact of laser process parameters on the material removal mechanism by performing deep machining. Different scan rates and a number of over-scans have been employed to understand the material removal mechanism, which is dominated by laser ablation and aided by melting due to the residual surface temperature. The maximum material removal rate of 21.75 mm3/min has been achieved for the scan rate of 300 mm/s. This can be related to the reduction in the ablation threshold and the critical balance between the material removal mechanism by ablation and melting. It was found that, the surface roughness of the cut surface has decreased due to melting and solidification. The cross-sectional examination reveals two distinct surface structures, which are entirely resolidified and thermally eroded regions. [ABSTRACT FROM AUTHOR]

A review of the recent developments in the field of lasing with liquid crystals (LCs) is presented. After an introduction into the principle of lasing the different relevant liquid crystal phases to the field are introduced, namely, the nematic and chiral nematic phase, Blue Phases, twist grain boundary and ferroelectric liquid crystals. The classic examples of liquid crystal lasing are shortly discussed, together with a variety of possibilities for tuning the lasing wavelength, before the modern trends in LC lasing are discussed in detail. These are particularly random lasers, where the effects of nanoparticles, quantum dots and solitons are highlighted, as well as localized surface plasmon resonance. Other modern laser systems that have attracted recent interest, white lasers, whispering gallery mode lasers and those with biological materials, for example, cellulose nanocrystals, are also introduced and the latest developments outlined. [ABSTRACT FROM AUTHOR]

Non-muscle invasive bladder cancer (NMIBC) is currently mainly treated with the approach of transurethral resection of bladder tumor (TURBT) followed by pathology investigation of the obtained specimens. However, this approach—TURBT—has a few drawbacks, owing to the inherent technical defect—"piecemeal" resection. With development of medical science and surgical techniques, a new kind of surgical operation—"en bloc" resection of bladder tumor (ERBT)—emerged, hoping to completely remove bladder tumor with surrounding normal tissue. The detrusor muscle layer beneath the tumor is removed, and the surgical quality of bladder tumor is enhanced, with a better pathological outcome, reduced intraoperative complications and lower recurrence rate eventually. This paper reviews current literature concerning a brief history of ERBT developing, surgical steps, its indications, advantages on surgical margin, recurrence during follow-up, pathological performance—presence of detrusor muscle, residual tumor and upstage, as well as such issue as "is reTURBT necessary after ERBT?" and the guiding significance of ERBT in substaging of T1 bladder cancer. [ABSTRACT FROM AUTHOR]

Introduction and Objective: To report our initial experience with enhanced MOSES 2.0 technology in patients who underwent holmium laser enucleation of the prostate (HoLEP) for the treatment of benign prostatic hyperplasia (BPH), in comparison to those who underwent HoLEP with MOSES 1.0 technology at our institution. Methods: We retrospectively reviewed data of patients who underwent HoLEP using MOSES 1.0 or MOSES 2.0 pulse-modulation technology from December 2020 to September 2023. Preoperative and intraoperative parameters, postoperative outcomes, as well as perioperative complications were collected and analyzed. Results: A total of 196 patients were included in the study. Among them, 146 patients underwent MOSES 1.0 HoLEP, while 50 had MOSES 2.0 HoLEP. No statistically significant differences in preoperative characteristics were observed between the two groups. The median prostate volume for the MOSES 1.0 and MOSES 2.0 HoLEP groups was 109 cc and 117.5 cc, respectively. Patients in the MOSES 2.0 group had a shorter median enucleation time (52.5 vs. 42.5 min, p < 0.001) and hemostasis time (8 vs. 6 min, p = 0.002), along with lower laser energy usage (101 vs. 86.4 kJ, p = 0.012), when compared to those in the MOSES 1.0 cohort. Postoperative outcomes, including IPSS, QoL, Qmax, and PVR, were comparable between the two groups at 1, 3, and 6 months postoperative. The incidence of hospital readmission (p = 0.42), as well as one-month postoperative urge urinary incontinence (p = 0.2) and stress urinary incontinence (p = 0.13) were also comparable between the cohorts. Conclusions: HoLEP with second-generation MOSES 2.0 technology is a safe and effective treatment option for BPH. It offers notable improvements, including reduced enucleation and hemostasis times, while using less energy when compared to MOSES 1.0. [ABSTRACT FROM AUTHOR]

ABSTRACT Background Methods Results Conclusions Melasma is a chronic condition characterized by dark patches on the facial skin. It has a known female gender dominancy, and women usually think of melasma as being a serious cosmetic problem. Treatment of melasma can be seriously challenging, thus, dermatologists may employ different approaches for melasma. This study aimed to investigate how dermatologists diagnose and treat patients with melasma and to present the general characteristics of patients with melasma.A survey was conducted using Google Forms targeting dermatologists in Turkiye. A total of 199 dermatologists (142 females/57 males) participated in the study.Most of the participants (52.3%) were residents. Majority gender of the patients was female and most common age range of patients with melasma was 30–40 years. Mixed melasma was the most common type (57.4%). Malar region was the most frequent location (58.6%). Wood's lamp examination was used by 25.6% of the participants. Topical treatment was the first‐line choice for melasma therapy (95%), with Kligman's formula being the most used topical agent (69.8%). Oral therapy was not used by 70.8% of the participants. Tranexamic acid was the first choice for oral treatment (23.4%). Only 24.9% of the dermatologists used laser/light therapy, and Q‐switched Nd‐YAG laser was the most preferred device (58%). The most common recurrence rate was 41%–60% (45.9%).The findings of the current study investigating the melasma management in Turkiye revealed a female predominance and peak prevalence in the 30–40 years age group. Kligman's formula is the preferred topical treatment, whereas oral tranexamic acid remains underutilized. Recurrence rates are high, highlighting the need for preventative strategies. This study emphasizes the importance of personalized approaches and ongoing research for effective melasma management. [ABSTRACT FROM AUTHOR]

Importance: Stapedectomy is an effective treatment option for patients with symptomatic otosclerosis. A common surgical technique today is laser stapedotomy, although the equipment required adds a significant cost to the procedure and may not be available in certain, particularly remote, centers. This study aimed to evaluate cold steel stapedectomy in a modern otology practice as a cost-effective and versatile alternative. Objective: The primary objective was to evaluate the efficacy and safety of cold steel stapedectomy. The secondary objectives included characterizing the prevalence of relevant computed tomography (CT) findings and evaluating other factors such as piston size. Design: A retrospective case series from April 2006 to November 2021. Setting: A single tertiary care hospital in Montreal, QC, Canada. Participants: Patients with suspected otosclerosis and no prior stapes surgery. Intervention: Cold steel primary stapedectomy. Main Outcome Measures: In primary analysis, change in pure tone thresholds, pure tone average (PTA), and complication rates were obtained. Secondary analysis measures included rates of relevant CT findings and change in PTA with piston size. Results: A total of 302 cases were included in the analysis. The average change in air conduction PTA was a decrease of 27 dB, with 91% (276/302) having over 10 dB of improvement. The air-bone gap was closed to within 10 dB in 82% (248/302) of cases and within 20 dB in 96% (290/302) of cases. Overclosure occurred in 19% of cases, while only 4% resulted in worsened PTA bone conduction thresholds. In secondary analysis, 74% of CT scans demonstrated radiologic otosclerosis. Other findings included suspected superior semicircular canal dehiscence in 1.8%. Conclusion: Cold steel stapedectomy was demonstrated to be a safe and effective technique, with audiometric results comparable to laser and drill studies in recent literature. It should be considered as a cost-effective and global health accessible alternative. Additionally, CT scans can provide valuable information in the pre-operative workup. [ABSTRACT FROM AUTHOR]

Summary This case report describes the clinical presentation, surgical treatment, post‐operative management and outcome of a bronchocutaneous fistula with intrathoracic abscessation in a yearling horse. The animal was presented with a history of several months of persistent coughing and a cutaneous fistula located over the right ventral hemithorax. The yearling had purulent discharge similar in character from both nares and draining out of the fistula. A bronchocutaneous fistula with intrathoracic abscessation was diagnosed by endoscopic examination of the cutaneous fistula. The treatment initially consisted of cyanoacrylate applied topically to the affected bronchi under endoscopic guidance, which was not successful. The fistula was successfully sealed with a diode laser used to create local inflammation at the site. One week after the second intervention, the patient's clinical signs resolved and the fistula was completely sealed 10 weeks following intervention. Follow‐up at 16 months revealed that the patient was doing well and clinically normal. [ABSTRACT FROM AUTHOR]

Phase change materials (PCMs) have gained a tremendous interest as a means to actively tune nanophotonic devices through the large optical modulation produced by their amorphous to crystalline reversible transition. Recently, materials such as Sb2S3 emerged as particularly promising low loss PCMs, with both large refractive index modulations and transparency in the visible and near‐infrared. Controlling the local and reversible phase transition in this material is of major importance for future applications, and an appealing method to do so is to exploit pulsed lasers. Yet, the physics and limits involved in the optical switching of Sb2S3 are not yet well understood. Here, the reversible laser‐induced phase transition of Sb2S3 is investigated, focusing specifically on the mechanisms that drive the optically induced amorphization, with multi‐physics considerations including the optical and thermal properties of the PCM and its environment. The laser energy threshold for reversibly changing the phase of the PCM is determined through both theoretical analysis and experimental investigation, not only between fully amorphous and crystalline states but also between partially recrystallized states. Then, the non‐negligible impact of the material's polycrystallinity and anisotropy on the power thresholds for optical switching is revealed. Finally, the challenges related to laser amorphization of thick Sb2S3 layers are addressed, as well as strategies to overcome them. These results enable a qualitative and quantitative understanding of the physics behind the optically‐induced reversible change of phase in Sb2S3 layers. [ABSTRACT FROM AUTHOR]

ABSTRACT Background Aims Methods Results Conclusions Many people are interested in addressing visible signs of aging with non‐invasive cosmetic treatments. Development of effective topical products will provide options to delay or support cosmetic procedures.This study assessed and compared the efficacy and tolerance of a topical product used over the course of 16 weeks to a single ablative laser treatment on women with moderate global photodamage on the face.Subjects in Cell 1 (Laser Cell) were treated over the entire face with a fractional CO2 laser system. Subjects in Cell 2 (Topical Serum Cell) were treated with a topical serum containing hydroxypinacolone retinoate and peptides over the entire face, twice per day for 16 weeks. The study was composed of 71 women, with 29 in the Laser Cell (mean age 56.2) and 42 in the Topical Serum Cell (mean age 55.0), between 40 and 65 years old. Expert grading was used to determine efficacy parameters.Participants in the Topical Serum Cell achieved more significant improvement (p < 0.05) in Marionette lines, fine lines (global face), wrinkles (global face), wrinkles (crow's feet), nasolabial folds, texture, smoothness (tactile), global hyperpigmentation, lift, and photodamage compared to participants in the Laser Cell. Participants in the Topical Serum Cell achieved parity in the look of fine lines (crow's feet), forehead lines, glabella, firmness/bounce (tactile), skin tone evenness, radiance.While no statistically significant differences in tolerability were observed, treatment with the topical cosmetic product achieved parity or statistically better improvement in parameters compared to laser treatment at 16 weeks. [ABSTRACT FROM AUTHOR]

Introduction: Apical periodontitis (AP) is an inflammatory disease of the periapical tissues that is often asymptomatic and diagnosed through radiographic examination. A challenge in traditional endodontics is disinfection of the root canal system (RCS), which anatomically presents numerous variations, often leading to persistent infections. Antimicrobial photodynamic therapy (aPDT) and photobiomodulation therapy (PBMT) offer promising adjuncts, due to their antimicrobial and tissue-healing properties. Objective: The aim of this article was to report five cases of teeth with pulp necrosis and asymptomatic apical periodontitis (AAP) treated with aPDT and PBMT protocols. Materials and Methods: Five cases of pulp necrosis and AAP were treated with conventional endodontic therapy supplemented with aPDT and PBMT. The treatment protocol included chemomechanical preparation (CMP), aPDT using a 660 nm diode laser (DL) with methylene blue (MB) as a photosensitizer (5 min pre-irradiation time), and PBMT using a 940 nm DL. Treatment results were evaluated through cone-beam computed tomography (CBCT)-based evaluation over 1 year of clinical follow-up. Results: All cases showed significant bone regeneration and tissue healing, demonstrating the efficacy of the combination of aPDT and PBMT. Post-operative pain did not occur in any of the patients, suggesting a possible analgesic effect of PBMT. Conclusions: The combination of aPDT and PBMT in endodontic therapy promoted tissue recovery and improved the prognosis of AAP. Further research and randomized control trials are needed to optimize treatment protocols and evaluate the long-term effects. [ABSTRACT FROM AUTHOR]

Acne has a prevalence of over 90% among adolescents, and subsequently progresses to acne scarring in approximately 47% of cases. Due to the severe psychological and social ramifications acne scarring has on patients, there is a need for more effective treatments. Platelet-rich plasma (PRP), an autologous preparation enriched with growth factors, cytokines, and chemokines, has shown efficacy in promoting wound healing and tissue remodeling in dermatology. Recent evidence suggests that the efficacy of PRP may be enhanced when combined with laser therapy, which induces controlled tissue damage through photo-thermolysis thereby promoting tissue remodeling and epidermal regeneration. The microchannels created by laser treatments are thought to allow deeper penetration of PRP into the skin, potentially increasing its therapeutic effects. This review aims to analyze the combined use of PRP and laser therapy for treating acne scarring by examining randomized control trials from the past decade indexed on PubMed. Six studies met our inclusion criteria and were included in this review. The findings of this review support the hypothesis that combining PRP with laser therapy offers superior clinical results compared to monotherapy, providing a more effective approach to managing acne scarring. [ABSTRACT FROM AUTHOR]

Background: Different types of dental laser can be used instead of the traditional hand and rotary files in root canal treatment with highly acceptable performance. Laser devices emit an intense and focused light energy, which interacts with biologic tissues, for pulp removal, shaping and cleaning the dentinal walls to be finally sealed with gutta-percha. Various laser devices with different wavelengths such as CO2, Er:YAG, Nd: YAG and Diode present the best laser–tissue interaction. Lasers in root canal treatment show more advantages than traditional treatment. Laser is more accurate than conventional root canal treatment that allow minimal removal of healthy dentinal tissue. Lasers have anti-bacterial effect by reduction of more than 99.7% bacterial counts for root canal sterilization. Laser provides less bleeding, inflammation, pain, discomfort and infection than conventional procedures. Laser treatment of root canals results in a good sealing of gutta-percha to root canal walls to prevent infections. Conclusions: Laser application is comfortable to the patients by removing the disturbing sounds of drills and decreasing the need for local anesthesia. It decreases the need for suturing in endodontic surgery due to better hemostasis, thus getting clean and well-sealed surgical wounds. [ABSTRACT FROM AUTHOR]

Polymer stabilized blue phase (PSBP) liquid crystal has aroused wide attention due to its broad temperature range and potential applications in flexible display, multi‐mode monitor, and mirrorless laser based on its well‐compatible stability and multi‐responsiveness, such as electricity, humidity, and temperature. Temperature produces an important effect on the structure/optical properties of PSBP, but there lack of detailed investigation on thermal‐induced deformation and its influence on the optical performance of PSBP. Here, the thermal‐induced evolution of structure/optical properties of PSBP with different polymer content is in situ characterized by variable‐temperature ultra‐small‐angle X‐ray diffraction, Kossel diffraction, and polarized optical microscopy. A restricted deformation of PSBP cubic lattice is revealed by the shift of reflective wavelength and evolution of Kossel diagrams, which is mainly attributed to the thermal‐induced phase transition/separation of non‐polymerized components. The thermal stability of PSBP is improved by increased polymer content based on the limited deformation ability. This work is significant for the design of novel functional material, which paves the way for the preparation of photonic crystal soft materials with high stability and optical quality. [ABSTRACT FROM AUTHOR]

The rates of mortality and morbidity from treatment failures have increased due to microorganisms' growing resistance to antimicrobial medicines, signaling a severe hazard in the near future. Copper oxide (CuO) nanoparticles (NPs) were prepared using the laser penetration in water (LPW) method, which is regarded as an innovative and effective technique for producing a wide range of nanomaterials. The physical properties of the prepared NPs were studied by identifying them by dynamic light scattering (DLS), UV–visible spectroscopy (UV–Vis), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), field emission scanning electron microscope (FESEM), and energy-dispersive X-ray analysis (EDX). The absorption spectrum showed two peaks, one with a modest intensity at 650 nm and the other at 280 nm. In the optical characteristics study, the band gaps estimated for the CuO NPs are 3.6 eV. XRD shows the prepared CuO NPs have a polycrystalline structure with a pre-indication particle size of approximately 35 nm. The DLS results showed that the synthesized CuO nanoparticle has 35.19 ± 12.82 nm in size and − 21.3 ± 6.56 in charge. FESEM image shows that CuO NPs have a homogeneous distributed spherical shape with some accumulation NPs in a cauliflower-like shape. Antibacterial activity of the prepared nanoparticles was tested against two types of bacterial strains, gram-positive bacteria Staphylococcus aureus (S. aureus) and gram-negative bacteria Escherichia coli (E. coli), isolated from the infected wounds. AgNO3 was used as a control to compare with different concentrations of CuO NPs. The result indicated the antibacterial activity of CuO NPs was concentration-dependent and exceeded the antibacterial activity of the control agent (AgNO3). At CuO NPs, the maximum concentration used was 200 µg/ml, and the inhibition zone was 16.5 mm and 15 mm for E. coli and S. aureus, respectively. [ABSTRACT FROM AUTHOR]

In this in vitro study, we aimed to evaluate and compare the antibacterial efficacy of a novel erbium-doped yttrium aluminum garnet laser modality, shock wave enhanced emission of photoacoustic streaming (SWEEPS), ultrasonically activated irrigation (UAI), and single needle irrigation (SNI) against old bacterial biofilm. A two-week-old Enterococcus faecalis biofilm was cultivated on transversal dentinal discs made from the middle third of the roots of single-rooted, single-canal premolars. Biofilm growth was confirmed using scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM). The dentine samples were randomly distributed into three experimental groups and one control group based on the irrigation protocol used: Group 1, SWEEPS; Group 2, UAI; and Group 3, SNI. The root canals were irrigated with a 3% sodium hypochlorite solution. Antibacterial efficacy was evaluated quantitatively through bacterial culture and qualitatively through CLSM and SEM. Both SWEEPS and UAI demonstrated a statistically significant reduction in Enterococcus faecalis colony-forming units (CFUs) (p < 0.001), while SNI did not show a statistically significant reduction (p = 0.553). No significant difference was observed between the efficacy of SWEEPS and UAI (p > 0.05). The SWEEPS and UAI techniques were equally effective in eliminating mature E. faecalis biofilm. [ABSTRACT FROM AUTHOR]

Background and Objective: Eliminating intracanal Enterococcus faecalis (E. faecalis) is challenging because of its ability to penetrate deep dentinal tubules and its high resistance to many chemicals. This study evaluated the effectiveness of conventional needle irrigation and three different irrigant activation methods in reducing E. faecalis. Methods: The root canals of extracted teeth were shaped, contaminated with E. faecalis, and incubated for three weeks. They were randomly allocated to four experimental groups of 15 teeth each according to the final irrigation Method: group 1, conventional needle irrigation; group 2, passive ultrasonic (PU) irrigation; group 3, XP-endo Finisher (XPF); and group 4, laser-activated (LA) irrigation. Bacterial samples were taken and cultured before and after these final irrigation procedures. The colony-forming units were counted, and the bacterial reduction percentages of each group were calculated. The Kruskal-Wallis and Dunnet tests were used for statistical analysis. Results: All irrigant activation methods were significantly more effective than conventional needle irrigation. Although the LA group generated more negative samples than PU, there was no statistically significant difference between the LA and PU groups. LA was significantly more effective than the XPF, whereas PU and XPF were statistically similar. Conclusions: Within the limitations of this study, the final irrigation with LA and PU showed the best reductive effect on E. faecalis colonies. Considering that the LA group had more negative samples, it may be chosen as an alternative to enhance root canal disinfection, especially in difficult cases. [ABSTRACT FROM AUTHOR]

In order to design an economical and reliable LiDAR, it is necessary to quantify the influence of different factors on the attenuation of laser propagation in water. Although these factors have been widely investigated, a complete understanding is still few. In addition, a comparative analysis between the measured data and the simulation results of LiDAR to build the design of LiDAR is still lacking. For these reasons, a semi-analytical Monte Carlo method was applied to establish a simulation model of the underwater laser echo signal propagation. The control variable method was quantified with the three major types of influencing factors: 1) LiDAR system parameters, 2) water optical characteristics and 3) external conditions. The effects of these different influencing factors on laser underwater echo signal transmission were investigated. With the experimental results, the attenuation rate of laser transmission in turbid harbour was 7.1 and 19.2 times higher than that in coastal water and clean ocean. Compared with other influencing factors, the optical characteristics of water have the most significant influence on underwater laser transmission. The laser echo signals in water with different concentrations of suspended solids were investigated in a laboratory tank using a LiDAR prototype developed by our research group. The results were compared with that from the semi-analytical Monte Carlo simulation to further explore the influence of the inherent optical characteristics of water on laser energy attenuation. The experimental results showed that with increasing water turbidity, the light beam diverged by strong scattering, the size of the light spot increased, the energy of the echo signal decreased as a whole and the backscattering signal of the water changed significantly. The determination coefficients and relative errors of the measured echo signals and the normalized simulation results were 0.99 and 0.01, respectively, which demonstrate the reliability of LiDAR prototype. [ABSTRACT FROM AUTHOR]

Subthreshold lasers operate below the threshold of visible tissue damage, thereby preventing ophthalmoscopically visible thermal damage to the chorio-retinal layers. They could represent a safe and effective alternative and/or adjunctive procedure to conventional lasers in treating diabetic macula edema (DME), central serous chorioretinopathy (CSCR), and branch retina vein occlusion (BRVO). This review focuses on the use of subthreshold micropulse laser (SMPL), its settings, and clinical applications. Despite their widespread use, a standardized protocol for sub-threshold laser settings has not been established yet, and thus, there is uncertainty in selecting effective and safe parameters for any specific situation. We conducted a comprehensive overview of the existing indications for subthreshold laser therapy and their settings for different retinal diseases. The debate revolves around which parameters could guarantee the safety of the procedure for each case, depending on the duty cycle, the laser wavelength, the spot duration, and the power, with laser power titration on one side or choosing a fixed lowered power value on the other side. SMPL therapy for DME, CSCR, and BRVO-associated macular edema has shown significant effectiveness in reducing the macular thickness, facilitating subretinal fluid absorptions, increasing the best corrected visual acuity (BCVA) and reducing the number of intravitreal injections (IVI) required annually. We presented a broad list of the laser parameters reported in the literature, organized into different tables divided based on the specific pathology, with the aim of providing a useful tool for future studies. [ABSTRACT FROM AUTHOR]

'Wet' age-related macular degeneration (AMD) is characterized by pathologic choroidal neovascularization (CNV) that destroys central vision. Abundant evidence points to inflammation and immune cell dysfunction in the progression of CNV in AMD. Mast cells are resident immune cells that control the inflammatory response. Mast cells accumulate and degranulate in the choroid of patients with AMD, suggesting they play a role in CNV. Activated mast cells secrete various biologically active mediators, including inflammatory cytokines and proteolytic enzymes such as tryptase. We investigated the role of mast cells in AMD using a model of CNV. Conditioned media from activated mast cells exerts proangiogenic effects on choroidal endothelial cells and choroidal explants. Laser-induced CNV in vivo was markedly attenuated in mice genetically depleted of mast cells (KitW−sh/W−sh) and in wild-type mice treated with mast cell stabilizer, ketotifen fumarate. Tryptase was found to elicit pronounced choroidal endothelial cell sprouting, migration and tubulogenesis; while tryptase inhibition diminished CNV. Transcriptomic analysis of laser-treated RPE/choroid complex revealed collagen catabolism and extracellular matrix (ECM) reorganization as significant events correlated in clusters of mast cell activation. Consistent with these analyses, compared to wildtype mice choroids of laser-treated mast cell-deficient mice displayed less ECM remodelling evaluated using collagen hybridizing peptide tissue binding. Findings herein provide strong support for mast cells as key players in the progression of pathologic choroidal angiogenesis and as potential therapeutic targets to prevent pathological neovascularization in 'wet' AMD. [ABSTRACT FROM AUTHOR]

Background and Objective: Removal of skin tattoos by Q‑switched (QS) Nd:YAG laser is a common procedure, but its results vary. For successful tattoo removal, laser applications are combined with various methods. In laser tattoo removal, pigments are removed from the region by the lymphatic system after they are broken down into small pieces. It is hypothesized that induction with platelet‑rich plasma (PRP) can increase the total amount of pigments removed in the laser tattoo removal process and possibly reduce the visibility of the remaining pigments by thickening and renewing the skin. For this purpose, a study investigating the combination of laser tattoo removal with PRP was planned. Materials and Methods: The study was planned on rats divided into three groups (with eight rats each). Four rats were used for PRP preparation. All rats were tattooed on both arms and legs. One month after the rats were tattooed, QS Nd:YAG laser and PRP or saline injections were applied to the tattoos. The tattoos were measured, photographed, and evaluated by macroscopy and dermoscopy shortly before laser application and at 1 and 2 months after laser application. Regional lymph node dissection was performed. Results: After laser application, all the tattoos showed some pigment removal. There was no significant difference in tattoo removal with various wavelengths (1064/532 nm) or with a 25% increase in laser power. Although skin quality was found to be better in the PRP‑injected group, the difference was not significant compared with that in the group with saline injections. In all subjects, at least one pigmented lymph node was seen in all dissection areas. Conclusions: Laser application is effective in the removal of tattoos. However, although the combination of PRP and laser has a positive effect on the quality of the skin, it does not provide a significant positive effect on tattoo removal. [ABSTRACT FROM AUTHOR]

Nerve injuries and neurodegenerative disorders remain serious challenges due to the poor results of nerve cell regeneration. The most promising treatment for such injuries is treatments based on stimulating cells to grow and differentiate stem cells in that area into nerve cells, but there are obstacles in controlling the growth and differentiation into fully functional nerve cells and research is ongoing to overcome these obstacles. In this study, polymethyl methacrylate (PMMA) and its laser modified surfaces were used for cell culture and differentiation into neuron-like cells. In order to show the differentiation of PC12 cells into neuron-like cells, the expression levels of the neuronal markers Map2 and Synapsin-1 were examined. The results showed the growth of PC12 on raw PMMA was increased significantly compared to the control group and micrometric parallel grooves lead to a significant difference in cell growth compared to raw PMMA. Also, the simultaneous irradiation of laser to the cell cultured on PMMA caused more cell adhesion on the surface, faster growth and differentiation of PC12 into neuron-like cells. [ABSTRACT FROM AUTHOR]

It has been suggested that 'transient surface currents' caused by multi-MeV fast electrons can be responsible for the emission of low frequency radiation (e.g. in THz range) from ultra-intense laser–solid interactions. This mechanism has been analyzed, and analytic upper bounds on the intensity, electric field amplitude, and normalized vector potential have been developed and tested against 1D EM Particle-in-Cell simulations. The 'transient surface current' mechanism is effective and sufficiently efficient to fully account for all radiation that has been emitted in experiments so far. [ABSTRACT FROM AUTHOR]

In this manuscript, a laser ablation-assisted step milling (LAAM(S)) process was proposed, building upon the foundation of laser-ablation assisted overall milling (LAAM(O)). The model of the oxidation mechanism of SiC f /SiC composites was developed to explain the evolution of material properties with laser assistance. The results of the oxidation revealed that the material undergoes melting and evaporation, forming an ablation layer, and the thickness of the ablation layer is positively correlated with laser power. In comparison to CM and LAAM(O), LAAM(S) demonstrates notable reductions in milling forces and temperatures, with corresponding decreases in tool wear of 55 μm and 30 μm respectively. These improvements are attributed to the porous and loosely adherent ablation layer, facilitating easier removal，demonstrating the effectiveness of the developed machining method. Unlike CM and LAAM(O), LAAM(S) prevents tool edge chipping and reduces surface damages such as fiber fracture and matrix fragmentation. The machining efficiency was quantitatively evaluated. The processing time reduced by 13.65 % in LAAM(S) compared to LAAM(O) when the milling distance reached 500 mm. This indicates that LAAM(S) offers superior efficiency in long-distance processing. Therefore, LAAM(S) proves to be a feasible and effective method for improving the machinability and efficiency of SiC f /SiC composites. [ABSTRACT FROM AUTHOR]

Background and Objectives: Melasma, a hypermelanotic dermatologic condition that mainly affects women, poses challenges due to its complex etiology involving environmental and genetic factors. Its pathophysiology, marked by intricate histological changes, is not fully understood. This study explored the efficacy and safety of a new 785 nm picosecond laser in treating facial melasma. Materials and Methods: An 11-participant cohort, comprising women with Fitzpatrick phototypes II-III, underwent a treatment protocol with a new 785 nm picosecond laser. The clinical evaluation used the Global Aesthetic International Score (GAIS) and the Five-Point Likert Scale Questionnaire. The aim of the study was to understand the capacity of the 785 nm wavelength laser to interact with both the pigmentary and vascular components of melasma. Results: The GAIS outcomes revealed excellent (18.2%), good (54.5%), poor (18.2%), and no results (9.1%). The Likert Scale responses varied from very satisfied (18.2%) to slightly satisfied (9.1%). Clinical images at three months demonstrated resolution of melasma with no adverse events. Conclusions: This non-invasive procedure showed positive outcomes and high patient tolerance, emphasizing its potential in melasma management. However, in order to fully understand the interactions of pigmentary and vascular components with the 785 nm wavelength laser, further research is required. The small cohort represents a limitation for this study, therefore studies that include a larger number of patients are needed to assess the effectiveness of this laser treatment for facial melasma. [ABSTRACT FROM AUTHOR]

Micro-stereolithography (μ SL) is an advanced additive manufacturing technique that enables the fabrication of highly precise microstructures with fine feature resolution. One of the primary challenges in μ SL is achieving and maintaining precise focus throughout the fabrication process. For the successful application of μ SL, it is essential to maintain the sample surface within a focal depth of several microns. Despite the growing interest in auto-focus devices, limited attention has been directed towards auto-focus systems in image-based auto-focus microscope systems for precision μ SL. To address this challenge, we propose an image-based auto-focus microscope system incorporating visual servo control. In the optical design, a transflective beam splitter is employed, allowing the laser beam to pass through for fabrication while reflecting the focused beam on the sample surface to the microscope and camera. Utilizing captured spot images and the Foucault knife-edge test, a deep learning-based laser spot image processing algorithm is developed to determine the focus position based on spot size and the number of spot pixels on both sides. Experimental results demonstrate that the proposed auto-focus system effectively determines the relative position of the focal point using the laser spot image and achieves auto-focusing through visual servo control. [ABSTRACT FROM AUTHOR]

In this article, we discuss the scientific research we conducted to ensure information security on concrete structures using the fiber Bragg grating method. As a result, guided by the experiences of other researchers and their results in our studies, the main hazards were identified, and the influence of temperature and deformation sensors in concrete was studied. The work determines the dependence of temperature on the optical cable and its effect on concrete deformation. It also studies the change in the internal structure of the optical fiber when exposed to concrete, and in comparison, with non-concrete optical fiber. In the experimental chapter, conducted on laboratory bench, we consider and study the signal transmission structure of an optical sensor that experiences deformation upon impact with concrete and such fibers. Graphic data was obtained using the OptiSystem program. During the process of determining the optical power of the sensors, we discovered that the higher the vibration during signal transmission, the higher the power of the optical data acquisition system unit. The results presented in this paper show the promise of fiber optics in other environments, as well as new discoveries in the construction industry and the successful use of electrical laser sensors to maintain temperature and stress in a variety of concrete structures, including cooling towers in nuclear and thermal power plants. [ABSTRACT FROM AUTHOR]

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Conventional synthetic sorbents for oil spill cleanup are the most widely employed materials, although a major drawback is the extensive chemical modification that they have undergone, making them economically and environmentally nonsustainable. The use of inexpensive, abundant, nontoxic, biodegradable, and reusable lignocellulosic materials might be an alternative to conventional sorbents, with obvious positive impact on sustainability and circular economy. The present study subsequently utilizes the well‐established process, of converting grape molasses—a byproduct of the winemaking industry that represents a typical and abundant source of biomass—into a laser‐assisted graphene‐like product (LA‐B). Comparative experiments were carried out with two additional materials that are similarly produced by the same laser‐assisted method, yet use synthetic polyimide foil and tape polymers as precursors, namely LA‐F and LA‐T. The results showed that diesel oil adsorption capacity of LA‐B was 33.5 g/g, while the ultraoleophilic LA‐T adsorbed 57 g/g and LA‐F adsorbed 41 g/g. Furthermore, the crude oil uptake was 31.1, 56.0, and 38.6 g/g for LA‐B, LA‐T, and LA‐F, respectively. The adsorption of oil on the used materials could be well‐described by pseudo‐second‐order kinetics, showing that over 80% of oil was removed from the water within 15 min. [ABSTRACT FROM AUTHOR]

Underwater wireless optical communication (UOWC) systems have lately garnered a significant amount of attention for both academic purposes and trial applications. Although the idea is not new, the fact that seawater has a smaller window of absorption for blue-green light has reawakened interest in it, and it has grown an essential attraction because of its high bandwidth, it can cover a wide variety of underwater activities as compared to radio frequency and acoustic technologies. To monitor pollution, maintain oil pipelines, monitor climate change, conduct offshore investigations, and conduct oceanography research, the wireless transmission of information underwater technology is of importance to the military, industrial, and scientific organizations all around the world. The use of wavelengths of visible light to transmit secure data across point-to-point connections in underwater optical wireless communication (UOWC) compares well with the usage of free-space optical (FSO) communications. However, UWOC systems also have a huge amount of absorption and scattering introduced by the aquatic channels. Different from standard terrestrial free-space optical communication, many unique system design strategies have been investigated in recent years to solve these technological issues. This article presents a vision as well as various obstacles in the domain of underwater optical wireless communication, a detailed overview, and comparison of underwater communications techniques (UOWC) links, basic modulation technique techniques, and c pursuits on UWOC. [ABSTRACT FROM AUTHOR]

We propose an original design for a HgCdTe-based terahertz vertical-cavity surface-emitting laser with twenty 5 nm HgTe quantum wells. Feasibility of laser generation at 9 THz and a lattice temperature of 8 K is shown. The estimate of the threshold pump intensity using laser radiation at a wavelength of 5 μm is 3 W/cm2, which makes it possible to expect continuous wave (CW) mode lasing. Such a low required pump intensity will make it possible to create a very compact system of a laser pumped by CW mid-infrared quantum cascade laser. [ABSTRACT FROM AUTHOR]

Low thermal diffusivity of NiTi-based smart alloy results in concentrated heat accumulation during laser beam machining which rises to adverse thermal effects like heat-affected zones, residual stresses, and alterations in microstructure of shape memory alloy (SMA) system. The addition of Cu and Zr can reduce the thermal hysteresis in the phase transformation of NiTi SMAs. Minimizing thermal hysteresis is desirable in SMA applications where precise control of the phase transformation temperatures is required, such as in actuators, sensors, and medical devices. Therefore, aqua jet integrated laser (AJ-FLBM) machining is a suitable choice for smart materials that need to be machined with high precision and low heat affected zone. In this current research, the NiTiCuZr SMA is machined using AJ-FLBM to investigate the effects of process variables on surface characteristics measured using RSM-BBD approach. The surface quality was enhanced by 68.93% with a gradual decrease in laser power (P), cutting speed (CS), and an increase in frequency (F). Aqua jet integrated FLBM technique may reduce heat affected zone due to the removal of heat in areas near the cutting location. This was confirmed by the DSC test which reveals that optimal machining inputs do not alter shape memory properties. [ABSTRACT FROM AUTHOR]

We demonstrate a genuine method for three-dimensional pictorial reconstructions of two-dimensional, three-dimensional, and hybrid specimens based on confocal Raman data collected in a back-scattering geometry of a 532-nm setup. The protocol, or the titular PRISM (Phase-Resolved Imaging Spectroscopic Method), allows for sub-diffractive and material-resolved imaging of the object's constituent material phases. The spacial component comes through either the signal distal attenuation ratio (direct mode) or subtle light-matter interactions, including interference enhancement and light absorption (indirect mode). The phase component is brought about by scrutinizing only selected Raman-active modes. We illustrate the PRISM approach in common real-life examples, including photolithographically structured amorphous Al2O3, reactive-ion-etched homoepitaxial SiC, and Chemical Vapor Deposition graphene transferred from copper foil onto a Si substrate and AlGaN microcolumns. The method is implementable in widespread Raman apparatus and offers a leap in the quality of materials imaging. The lateral resolution of PRISM is stage-limited by step motors to 100 nm. At the same time, the vertical accuracy is estimated at a nanometer scale due to the sensitivity of one of the applied phenomena (interference enhancement) to the physical property of the material (layer thickness). [ABSTRACT FROM AUTHOR]