Fabrication and growth mechanism of t-selenium nanorods during laser ablation and fragmentation in organic liquids.

Introduction: The process of forming selenium nanoparticles with various shapes and structures through laser ablation and fragmentation in various solvents has been explored. Methods: Laser ablation and laser fragmentation techniques were employed using nanosecond Nd:YAG second harmonic laser irradiation in 9 different working fluids, including water. The characteristics of the resulting nanoparticles were assessed using transmission electron microscopy (TEM), dynamic light scattering (DLS), spectroscopy, and X-ray diffraction (XRD) methods. Results: Laser ablation and subsequent laser fragmentation of some organic solvents, such as ethanol, propanol-2, isobutanol, polyethylene glycol, and diethanolamine, have been found to produce trigonal selenium in the form of elongated nanorods approximately 1 µm long and 200 nm thick, with a well-defined crystal structure. In contrast, the use of deionized water, acetone, glycerol, and benzene as solvents results in the formation of spherical amorphous nanoparticles approximately 100 nm in diameter. Discussion: The polarity of the solvent molecules has been shown to influence the growth of crystalline selenium nanorods in solution during laser ablation and laser fragmentation. Generally, polar solvents hinder the growth of crystalline nanorods, due to interactions between selenium and solvent molecules. Nonpolar solvents, on the other hand, allow for laser fragmentation to reduce particle size and initiate the epitaxial growth of elongated, crystalline selenium nanorods.

Regeneration of Antifog Performance of Laser-Induced Copper-Based Micro-Nano Structured Surfaces by Rapid Thermal Treatment.

In this investigation, the laser marker ablation technique was employed on Cu-coated glass to fabricate micro-nanostructured antifog glass. The resulting surfaces exhibited a quasi-periodic micron hillock-hollow structure with dispersed nanoparticles distributed throughout, which played a role in the antifog property and superhydrophilicity. However, airborne organic pollutant deposition degraded the superhydrophilicity of ablated glass surfaces and, therefore, their antifog performance, which cannot be circumvented. Conventionally, furnace annealing for at least 1 h was used to decompose the organic pollutants and restore the superhydrophilicity, limiting the throughput and application scenario. Remarkably, the rapid regeneration of this property was achieved through either a 5 min rapid thermal treatment at 400 °C or a 1 s flame treatment. These are interventions that are hitherto unreported. Such short and simple treatment methods underscore the potential of laser-ablated glass for diverse practical applications.

Influence of Laser Power and Rotational Speed on the Surface Characteristics of Rotational Line Spot Nanosecond Laser Ablation of TC4 Titanium Alloy.

The TC4 titanium alloy is widely used in medical, aerospace, automotive, shipbuilding, and other fields due to its excellent comprehensive properties. As an advanced processing technology, laser processing can be used to improve the surface quality of TC4 titanium alloy. In the present research, a new type of rotational laser processing method was adopted, by using a beam shaper to modulate the Gaussian spot into a line spot, with uniform energy distribution. The effects of the laser power and rotational speed on the laser ablation surface of the TC4 titanium alloy were analyzed. The results reveal that the melting mechanism of the material surface gradually changes from surface over melt to surface shallow melt with the increase in the measurement radius and the surface roughness increases first, then decreases and, finally, tends to be stable. By changing the laser power, the surface roughness changes significantly with the variation in the measurement radius. Because low laser power cannot provide sufficient laser energy, the measurement radius corresponding to the surface roughness peak of the microcrack area is reduced. Under a laser power of 11 W, the surface roughness reaches its peak when the measurement radius is 600 µm, which is 200 µm lower than that of a laser power of 12 W, 13 W, and 14 W. By changing the rotational speed, the centrifugal force generated by the rotation of the specimen affects the distribution and re-condensation of the molten pool of the surface. As the rotational speed increases, the shallow pit around the pit is made shallower by the filling of the pit with molten material and the height of the bulge decreases, until it disappears. The surface oxygen content of the material increases first and then decreases with the increase in the measurement radius and gradually approaches the initial surface state. Compared with a traditional laser processing spot, the rotational line spot covers a larger processing area of 22.05 mm2. This work can be used as the research basis for rotational modulation laser polishing and has significance for guiding the innovative development of high-quality and high-efficiency laser processing technology.

Transient Ipsilateral Hemineglect Following Brain Laser Ablation in Patient with Focal Cortical Dysplasia.

Sensory integration is the province of the parietal lobe. The non-dominant hemisphere is responsible for both body sides, while the dominant hemisphere is responsible for the contralateral hemi-body. Furthermore, the posterior cingulate cortex (PCC) participates in a network involved in spatial orientation, attention, and spatial and episodic memory. Laser interstitial thermotherapy (LiTT) is a minimally invasive surgery for focal drug-resistant epilepsy (DRE) that can target deeper brain regions, and thus, region-specific symptoms can emerge. Here, we present an 18-year-old right-handed male with focal DRE who experienced seizures characterized by sensations of déjà vu, staring spells, and language disruption. A comprehensive evaluation localized the seizure focus and revealed a probable focal cortical dysplasia (FCD) in the left posterior cingulate gyrus. The patient underwent uneventful LiTT of the identified lesion. Post-operatively, he developed transient ipsilateral spatial neglect and contralateral sensory loss, as well as acalculia. His sensory symptoms gradually improved after the surgery, and he remained seizure-free after the intervention for at least 10 months (until the time of this writing). This rare case of ipsilateral spatial and visual hemineglect post-LiTT in epilepsy underscores the importance of recognizing atypical neurosurgical outcomes and considering individual variations in brain anatomy and function. Understanding the dynamics of cortical connectivity and handedness, particularly in pediatric epilepsy, may be crucial in anticipating and managing neurocognitive effects following epilepsy surgery.

Label-Free Exosome Analysis by Surface-Enhanced Raman Scattering Spectroscopy with Laser-Ablated Silver Nanoparticle Substrate.

Early diagnostics of breast cancer is crucial to reduce the risk of cancer metastasis and late relapse. Exosome, which contains distinct information of its origin, can be the target object as a liquid biopsy. However, its low sensitivity and inadequate diagnostic tools interfere with the point-of-care testing (POCT) of the exosome. Recently, Surface-enhanced Raman Scattering (SERS) spectroscopy, which amplifies the Raman scattering, has been proved as a promising tool for exosome detection. However, the fabrication process of SERS probe or substrate is still inefficient and far from large-scale production. This study proposes rapid and label-free detection of breast cancer-derived exosomes by statistical analysis of SERS spectra using silver-nanoparticle-based SERS substrate fabricated by selective laser ablation and melting (SLAM). Employing silver nanowires and optimizing laser process parameters enable rapid and low-energy fabrication of SERS substrate. The functionalities including sensitivity, reproducibility, stability, and renewability are evaluated using rhodamine 6G as a probe molecule. Then, the feasibility of POCT is examined by the statistical analysis of SERS spectra of exosomes from malignant breast cancer cells and non-tumorigenic breast epithelial cells. The presented framework is anticipated to be utilized in other biomedical applications, facilitating cost-effective and large-scale production performance.

Femtosecond Laser Ablation and Delamination of Functional Magnetic Multilayers at the Nanoscale.

Laser nanostructuring of thin films with ultrashort laser pulses is widely used for nanofabrication across various fields. A crucial parameter for optimizing and understanding the processes underlying laser processing is the absorbed laser fluence, which is essential for all damage phenomena such as melting, ablation, spallation, and delamination. While threshold fluences have been extensively studied for single compound thin films, advancements in ultrafast acoustics, magneto-acoustics, and acousto-magneto-plasmonics necessitate understanding the laser nanofabrication processes for functional multilayer films. In this work, we investigated the thickness dependence of ablation and delamination thresholds in Ni/Au bilayers by varying the thickness of the Ni layer. The results were compared with experimental data on Ni thin films. Additionally, we performed femtosecond time-resolved pump-probe measurements of transient reflectivity in Ni to determine the heat penetration depth and evaluate the melting threshold. Delamination thresholds for Ni films were found to exceed the surface melting threshold suggesting the thermal mechanism in a liquid phase. Damage thresholds for Ni/Au bilayers were found to be significantly lower than those for Ni and fingerprint the non-thermal mechanism without Ni melting, which we attribute to the much weaker mechanical adhesion at the Au/glass interface. This finding suggests the potential of femtosecond laser delamination for nondestructive, energy-efficient nanostructuring, enabling the creation of high-quality acoustic resonators and other functional nanostructures for applications in nanosciences.

Trace and Minor Element Analysis of Azurite Blues in Fine Arts: Possibilities and Limitations in Provenance Studies.

Azurite, a historical blue mineral pigment, has previously been described to contain certain elemental impurities. These may originate from host rocks, vein fillings, or the primary copper ore mineralization. In this study, azurites (and also green malachites) from three important Central European deposits with a potential of being exploited for pigment usage already in the Middle Ages have been studied, together with azurite from Chessy, France, with a different geological setting. Using electron probe microanalysis and, more importantly, laser ablation inductively coupled plasma mass spectroscopy for trace elemental analysis, several indicators were pinpointed as important for provenance: characteristic elemental fingerprint of the deposit, e.g., elevated lead (Pb) in combination with rare earth elements, may be combined with zinc (Zn)/arsenic (As) ratio (indicating sources of excess Zn in the primary deposit) and the overall amount of metal impurities (suggesting the source mineral of copper for azurite formation). In addition, malachites from the same deposits were found to preferentially incorporate primary ore metal elements as well as Cd, Mg, Mn, or U. Therefore, if azurite pigment contains an elevated amount of malachite as an impurity, it may significantly influence the overall elemental composition. The results obtained on geological samples were applied to two micro-samples of works of art containing azurite-rich layers originating from the 13th-14th and 16th centuries. It was shown that it is highly beneficial to focus on the overall trace elemental composition of the paint layer and not on the admixed mineral grains, as their presence, especially in minute micro-samples, is largely accidental and thus not representative. Although a higher number of samples need to be studied in the future, the newly described criteria made it possible to exclude some of the localities of the employed azurite pigment. This confirmed the key importance of trace elements analysis of mineral pigments for the provenance studies of fine arts.

Laser-Induced Periodic Surface Structures and Their Application for Gas Sensing.

Semiconducting metal oxides are widely used for solar cells, photo-catalysis, bio-active materials and gas sensors. Besides the material properties of the semiconductor being used, the specific surface topology of the sensors determines device performance. This study presents different approaches for increasing the sensing area of semiconducting metal oxide gas sensors. Micro- and nanopatterned laser-induced periodic surface structures (LIPSSs) are generated on silicon, Si/SiO2 and glass substrates. The surface morphologies of the fabricated samples are examined by FE SEM. We selected the nanostructuring and characterization of nanostructured source Ni/Au and Ti/Au films prepared on glass using laser ablation as the most suitable of the investigated approaches. Surface structures produced on glass by backside ablation provide 100 nm features with a high surface area; they are also transparent and have high resistivity. The value of the hydrogen sensitivity in the range concentrations from 100 to 500 ppm was recorded using transmittance measurements to be twice as great for the nanostructured target TiO2/Au as compared to the NiO/Au. It was found that such transparent materials present additional possibilities for producing optical gas sensors.

Fetoscopic laser photocoagulation: a medically reasonable treatment option in the management of types II and III vasa previa.

Vasa previa is a condition where unprotected fetal vessels cross the cervix within the membranes, posing a considerable risk of fetal death or severe morbidity if the membranes rupture before or during delivery. There has not been a definitive in utero treatment for this condition. Patients are typically closely monitored and hospitalized in the early third trimester and scheduled for cesarean delivery before term. This approach poses considerable physical, social, psychological, and financial challenges for pregnant patients and their families. Furthermore, fetal vessel rupture may lead to severe hypoxic-ischemic injury and consequent neurodevelopmental impairment. Finally, babies delivered early due to vasa previa may face both the short- and long-term consequences of prematurity. Recently, fetoscopic laser photocoagulation using a single-port fetoscope has emerged as a potential therapeutic option for patients with types II and III vasa previa. This innovative approach aims to reduce hospital stays, increases the chance of successful vaginal delivery, and potentially allows pregnancies to reach full term, providing lifelong benefits for the infant. Preliminary clinical studies on human subjects have demonstrated promising results concerning the feasibility, safety, and efficacy of this intervention for a subset of patients with types II and III vasa previa. After reviewing the current state of the art, we argued that offering fetoscopic laser photocoagulation in specialized centers under IRB supervision meets the ethical obligations of beneficence and non-maleficence for both pregnant and fetal patients, as well as the autonomy-based obligations for pregnant patients.

Dedifferentiation- and aging-induced loss of mechanical contractility and polarity in vascular smooth muscle cells: Heterogeneous changes in macroscopic and microscopic behavior of cells in serial passage culture.

Dedifferentiation and aging of vascular smooth muscle cells (VSMCs) are associated with serious vascular diseases, such as arteriosclerosis and aneurysm. However, how cell dedifferentiation and aging affect cellular mechanical behaviors at the single-cell and intracellular structure levels remains unclear. An in-depth understanding of these interactions is extremely important for understanding the mechanism underlying VSMC mechanical integrity and homeostatic regulation of vascular walls. Herein, we systematically investigated changes in VSMC morphology, structure, contractility, and motility during dedifferentiation and aging induced by serial passage culture using traction force microscopy with elastic micropillar substrates, laser nanodissection of cytoskeletons, confocal fluorescence microscopy, and atomic force microscopy. We found that VSMC dedifferentiation started in the middle stage of serial passage culture, accompanied by a transient cell spreading in the cell width and decrease in contractile protein expression. Dedifferentiated VSMCs showed a significant decrease in the contraction and stiffness of individual actin stress fibers; however, their overall cell traction forces were maintained. Simultaneously, a significant increase in cell motility and the number of actin fibers was observed in dedifferentiated VSMCs, which may be associated with the enhancement of cell migration and disruption of cell/tissue integrity during the early stage of vascular diseases. As cell senescence progressed in the later stage of serial passage culture, VSMCs displayed reduced cell spreading and migration with decrease in the overall cell traction forces and drastic reduction in mechanical polarity of cell structures and forces. These results suggested that cell senescence causes loss of mechanical contractility and polarity in VSMCs, which may be an important factor in vascular disease progression. The experimental systems established in this study can be powerful tools for understanding the mechanisms underlying cellular dedifferentiation and aging from a biomechanical perspective.

Release of ions enhanced the antibacterial performance of laser-generated, uncoated Ag nanoparticles.

Identifying the antibacterial mechanisms of elemental silver at the nanoscale remains a significant challenge due to the intertwining behaviors between the particles and their released ions. The open question is which of the above factor dominate the antibacterial behaviors when silver nanoparticles (Ag NPs) with different sizes. Considering the high reactivity of Ag NPs, prior research has primarily concentrated on coated particles, which inevitably hinder the release of Ag+ ions due to additional chemical agents. In this study, we synthesized various Ag NPs, both coated and uncoated, using the laser ablation in liquids (LAL) technique. By analyzing both the changes in particle size and Ag+ ions release, the impacts of various Ag NPs on the cellular activity and morphological changes of gram-negative (E. coil) and gram-positive (S. aureus) bacteria were evaluated. Our findings revealed that for uncoated Ag NPs, smaller particles exhibited greater ions release efficiency and enhanced antibacterial efficacy. Specifically, particles approximately 1.5 nm in size released up to 55 % of their Ag+ ions within 4 h, significantly inhibiting bacterial growth. Additionally, larger particles tended to aggregate on the bacterial cell membrane surface, whereas smaller particles were more likely to be internalized by the bacteria. Notably, treatment with smaller Ag NPs led to more pronounced bacterial morphological changes and elevated levels of intracellular reactive oxygen species (ROS). We proposed that the bactericidal activity of Ag NPs stems from the synergistic effect between particle-cell interaction and the ionic silver, which is dependent on the crucial parameter of particle size.

Magnetic Resonance-Guided Laser Interstitial Thermal Therapy in the Management of Hypothalamic Hamartomas: A Systematic Review and Meta-Analysis.

OBJECTIVE: Magnetic resonance-guided laser interstitial thermal therapy (MRg-LITT) is a promising new technique to ablate epileptic foci in patients with hypothalamic hamartoma (HH). We aim to systematically synthesize all available evidence and determine the effectiveness of MRg-LITT in reducing seizures in patients with HH. METHODS: We systematically searched MEDLINE (PubMed), Embase (Ovid), Scopus, and Google Scholar for all relevant articles. We used Open[Meta]Analyst to pool the number of seizure-free patients after MRg-LITT treatment in a random-effects model. Risk ratios were calculated, and subgroups were analyzed. Comprehensive meta-analysis was used to assess publication bias via funnel plots, Egger's regression test, and Begg's correlation test. This review complies with the Preferred Reporting Items for Systematic Review and Meta-Analyses guidelines. RESULTS: After screening the titles, abstracts, and full texts, we included 17 articles in our meta-analysis, which revealed a 77.1% rate of seizure freedom (95% confidence interval 0.696-0.837, P<0.001), with moderate heterogeneity (I2=49.46%). Subgroup analysis by study design and sensitivity analyses excluding 1 study at a time did not impact the results substantially, and we found no evidence of publication bias. Adverse effects included electrolyte imbalances, weight gain, and transient neurologic disturbances. CONCLUSIONS: MRg-LITT might be a feasible and effective technique for ablation of epileptic foci, leading to seizure freedom in a large proportion of patients with HH. However, there is a paucity of literature on the topic, and prospective clinical trials with larger number of participants comparing MRg-LITT to open surgery are needed.

Single-Cell Analysis of Elemental Contents by Laser Ablation-Inductively Coupled Plasma Mass Spectrometry.

Elemental analysis at the single-cell level is an emerging technique in the field of inductively coupled plasma mass spectrometry (ICP-MS). In comparison to the analysis of cell suspensions by fast time-resolved analysis, single-cell sampling by laser ablation (LA) allows the discriminatory analysis of single cells according to their size and morphology. In this study, we evaluated the changes in elemental contents in a single cell through differentiation of rat adrenal pheochromocytoma into neuron-like cells by LA-ICP-MS. The contents of seven essential minerals were increased about 2-3 times after the differentiation. In addition, we evaluated the degree of differentiation at the single-cell level by means of imaging cytometry after immunofluorescence staining of microtubule-associated protein 2 (Map2), a neuron-specific protein. The fluorescence intensities of Alexa Fluor 488-conjugated secondary antibody against the anti-Map2 primary antibody showed large variations among the cells after the onset of differentiation. Although the average fluorescence intensity was increased through the differentiation, there were still less-matured neuron-like cells that exhibited a lower fluorescence intensity after 5 days of differentiation. Since a positive correlation between the fluorescence intensity and the cell size in area was found, we separately measured the elemental contents in the less-matured smaller cells and well-matured larger cells by LA-ICP-MS. The larger cells had higher elemental contents than the smaller cells, indicating that the essential minerals are highly required at a later stage of differentiation.

Outcomes of CEM43 in Predicting Thermal Damage Induced by Focal Laser Ablation in Controlled Ex Vivo Experiments: A Comparison to Histology and MRI.

BACKGROUND: Focal laser ablation (FLA) serves as a targeted therapy for prostate cancer (PCa). Clinical studies have demonstrated significant variations in ablation volumes with consistent fiber configurations. Consequently, a prediction model is needed for the safe application of FLA in treating PCa. OBJECTIVE: This study aimed to evaluate the reproducibility of FLA-induced temperature profiles in controlled ex vivo experiments using clinical laser treatment protocols. Additionally, it sought to examine the effectiveness of the CEM43 model in predicting the zone of irreversible damage (ZID) and to compare these findings with outcomes derived from the Arrhenius model. METHODS: Freshly excised postmortem human prostate and porcine liver specimens were used for controlled ex vivo ablation. Tissues were secured in a Perspex sample holder for precise placement of the laser fiber and thermocouples. FLA was conducted with a 1064-nm Nd:YAG laser at 3 W in continuous-wave mode for 10 min. Pre- and post-FLA 3D T1-weighted 7 T MRI scans were obtained to assess the treatment area. Whole-mount hematoxylin and eosin histological slides were prepared and digitized. On histology, the ZID was defined as the total of vaporized, carbonized, and coagulated tissue. A 2D thermal development map was created from temperature data, using bi-cubic interpolation. The cumulative equivalent thermal isoeffect dose at 43°C in minutes (CEM43) model was applied to predict the ZID, with 240 equivalent minutes (240-CEM43) used as the damage threshold. Additionally, the Arrhenius thermal model was used for comparison of CEM43 results. Predicted ZIDs were compared to MRI and histology. RESULTS: FLA treatment was performed on ex vivo human prostate samples (n = 2) and porcine liver specimens (n = 5). For human prostate tissue, FLA did not result in an identifiable ZID upon histological macroscopic examination or a lesion on MRI. Ex vivo porcine liver samples showed a clearly demarcated oval-shaped hyperintense lesion surrounding the laser fiber tip on post-FLA MRI. The MRI lesion (range 1.6-2.1 cm2) corresponded with the shape and location of the ZID on histology, but was smaller (median 1.7 vs. 3.2, p = 0.02). Histological examination of porcine liver samples revealed ZIDs ranging from 2.1 to 4.1 cm2, whereas 240-CEM43-predicted ZIDs ranged from 3.3 to 3.8 cm2. Although the median 240-CEM43-predicted ZID was not significantly larger than the histology ZID (3.8 vs. 3.2 cm2, p = 0.22), it tended to overpredict the histological results in most experiments. The median Arrhenius-predicted ZID was similar to the histological ZID (3.2 vs. 3.2 cm2, p = 0.56), but varied in size when comparing individual experiments (range 2.5-3.2 cm2). CONCLUSION: FLA on ex vivo human prostate showed no thermal damage on histopathology or MRI. Ex vivo porcine liver FLA resulted in identifiable ZID on histology and lesions on MRI. 240-CEM43 generally overestimated the ZID and had less variability compared to histology. Results from the Arrhenius model were in better agreement with the histology findings, but still did not predict the individual FLA-induced histological thermal damage. Inter-experiment ZID variability underlines the need for developing a more comprehensive predictive dosimetry model for FLA in PCa treatment.

Comparative study between endovenous laser ablation (EVLA) with 1940 nm versus EVLA with 1470 nm for treatment of incompetent great saphenous vein and short saphenous vein: a randomized controlled trial.

BACKGROUND: To date, the most commonly used endothermal ablation method is endovenous laser ablation (EVLA). The objective of this work is to assess the initial and short-term outcomes of a 1940 nm diode laser compared with 1470 nm diode laser utilization for the treatment of lower limb varicose veins. METHODS: This is a randomized controlled prospective study that included patients with varicose veins. The allocated patients were randomized according to the technique used: group I, which was treated using EVLA with a 1940 nm diode laser, and group II, which was treated using EVLA with a 1470 nm diode laser. RESULTS: This study initially included 216 patients. After the exclusion of patients lost during follow-up, group I consisted of 105 patients, and group II consisted of 101 patients. There were high rates of anatomical success in the two groups with obliteration of the treated vessels at the 1-month follow-up (100% and 99%, respectively) and the 6-month follow-up (100% and 99%, respectively). A very low rate of adverse events was encountered (1%). Group II showed obviously longer median days to return for usual activities (11.5 compared with 7 days). They showed significantly higher pain scores, which was evident at the 7-day and 1-month follow-ups (P < .001). CONCLUSIONS: Both lasers provided excellent outcomes in terms of anatomical success and low rates of adverse events. The 1940 nm diode laser was associated with lower median days to return for usual activities and significantly lower pain scores. Evidently, lower power and linear endovenous energy density were required for this laser.

Accelerating the Hydrogen Evolution Kinetics with a Pulsed Laser-Synthesized Platinum Nanocluster-Decorated Nitrogen-Doped Carbon Electrocatalyst for Alkaline Seawater Electrolysis.

Efficient and durable electrocatalysts for the hydrogen evolution reaction (HER) in alkaline seawater environments are essential for sustainable hydrogen production. Zeolitic imidazolate framework-8 (ZIF-8) is synthesized through pulsed laser ablation in liquid, followed by pyrolysis, producing N-doped porous carbon (NC). NC matrix serves as a self-template, enabling Pt nanocluster decoration (NC-Pt) via pulsed laser irradiation in liquid. NC-Pt exhibits a large surface area, porous structure, high conductivity, N-rich carbon, abundant active sites, low Pt content, and a strong NC-Pt interaction. These properties enhance efficient mass transport during the HER. Remarkably, the optimized NC-Pt-4 catalyst achieves low HER overpotentials of 52, 57, and 53 mV to attain 10 mA cm-2 in alkaline, alkaline seawater, and simulated seawater, surpassing commercial Pt/C catalysts. In a two-electrode system with NC-Pt-4(-)ǀǀIrO2(+) as cathode and anode, it demonstrates excellent direct seawater electrolysis performance, with a low cell voltage of 1.63 mV to attain 10 mA cm-2 and remarkable stability. This study presents a rapid and efficient method for fabricating cost-effective and highly effective electrocatalysts for hydrogen production in alkaline and alkaline seawater environments.

Solid-state laser (266 nm) as an alternative to ArF excimer laser (193 nm) for corneal reshaping: Comparative numerical study of the thermal effect.

Laser corneal reshaping is a safe and effective technique utilized to treat common vision disorders. An advanced laser delivery system equipped with a pulsed UV laser with specific parameters is used to ablate parts of the cornea surface to correct the existing refractive error. The argon fluoride (ArF) excimer pulsed gas laser at 193 nm is the most employed type in the commercial devices for such treatments. This laser is generated using a mixture of Argon, Fluorine, and a significant amount of Neon gases. However, due to the ongoing Russian-Ukraine war, the availability of Neon gas is currently very limited, as this region is considered the primary supplier of pure Neon gas. Consequently we suggest replacing the common ArF laser source in the commercial devices with a solid-state (forth harmonic neodymium-doped yttrium aluminum garnet laser at 266 nm). This replacement uses the same operation parameters, optics, and scanning algorithm. Parameters from five commercial devices (Zeiss MEL 90, Technolas TENEO 317, Alcon Wave Light EX 500, Schwind Amaris 750 s, OptoSystems MICROSCAN VISUM) were compared with those of the i-ablation device, a research device that uses a 266 nm laser source. Our goal is to reduce production costs through a simple modification that has a significant impact. Consequently, the present study aims to find an alternative laser source for the current ArF laser without exchanging the complete system's design. This recommendation is based on a numerical simulation study. The thermal effect on a human cornea model was numerically evaluated using finite-element solutions of Pennes' bioheat equation on the COMSOL platform by applying two laser wavelengths. The results demonstrated that changing the laser source significantly impacts the thermal effect, even with the same laser settings. All studied devices showed a reduction in the thermal effect to below 40°C, compared with nearly 100°C under ordinary conditions.

Comparative efficacy of different thermal ablation and conventional surgery for the treatment of Papillary Thyroid Microcarcinoma: Systematic review including traditional pooling and Bayesian network meta-analysis.

PURPOSE: To compare the efficacy of different thermal ablation and conventional surgery for the treatment of Papillary Thyroid Microcarcinoma, using a systematic review including traditional pooling and Bayesian network meta-analysis. MATERIALS AND METHODS: A comprehensive literature search in PubMed, EMBASE, and the Cochrane Library databases identified retrospective studies evaluating the tumor volume change after different thermal ablation or conventional surgery. Studies from the date of their inception to January 6, 2024, were included. A review of 4463 potential papers, including a full-text review of 23, identified 10 eligible papers covering a total of 2658 patients for meta-analysis. The tumor volume change over a 12-month follow-up was compared between different thermal ablations. Tumor diameter change, complications, recurrence, operation and hospitalization time were evaluated by network meta-analysis. RESULTS: Based on the traditional frequentist approach, the overall pooled estimates for the standardized mean difference (SMD) in tumor volume change of radiofrequency ablation (RFA), laser ablation (LA), and microwave ablation (MWA) were 1.38 (95 % credibility interval (CI), 0.62-2.13), 1.94 (95%CI, 0.78-3.10) and 1.38 (95%CI, 1.01-1.75), respectively. Based on the Bayesian network meta-analysis, in examining the surface under the cumulative ranking area (SUCRA) ranking, RFA (SUCRA, 76.6), MWA (SUCRA, 66.6), and LA (SUCRA, 39.8) were identified as the three interventions that were associated with the greatest reduction in risk for complications compared with conventional surgery (CS), with RFA (SUCRA, 76.6) being ranked as the highest in safety. MWA, SMD 4.43 [95%CI, 2.68-6.17], RFA SMD 4.24 [95 % CI, 1.66-6.82], and LA SMD 4.24 [95 % CI, 1.48-7.00] were associated with the shorter operation time compared with CS. LA SMD 4.61 [95 % CI, 1.79-7.44] and MWA SMD 3.07 [95 % CI, 1.32-4.83] were associated with the shorter hospitalization time compared with CS, with LA (SUCRA, 86.5) yielding the highest ranking. MWA was associated with a reduced risk for tumor recurrence RR 0.02 [95 % CI, -0.44-0.49], compared with CS. CONCLUSION: We conducted a comprehensive review of the published literature on the effectiveness and safety of different thermal ablation techniques and conventional surgery for papillary thyroid microcarcinoma. Important research gaps persist due to a lack of long-term data and high-quality randomized controlled trials (RCTs).

Tools and methods for cell ablation and cell inhibition in Caenorhabditis elegans.

To understand the function of cells such as neurons within an organism, it can be instrumental to inhibit cellular function, or to remove the cell (type) from the organism, and thus to observe the consequences on organismic and/or circuit function and animal behavior. A range of approaches and tools were developed and used over the past few decades that act either constitutively or acutely and reversibly, in systemic or local fashion. These approaches make use of either drugs or genetically encoded tools. Also, there are acutely acting inhibitory tools that require an exogenous trigger like light. Here, we give an overview of such methods developed and used in the nematode Caenorhabditis elegans.