Ne Laser Research Articles

Optical Wavelength Calibration for Stabilized He–Ne laser 633 nm Using Substitution Method

Optical Wavelength Calibration for Stabilized He–Ne laser 633 nm Using Substitution Method

RBOH-dependent signaling is involved in He-Ne laser-induced salt tolerance and production of rosmarinic acid and carnosol in Salvia officinalis

BackgroundIn the past two decades, the impacts of Helium-Neon (He–Ne) laser on stress resistance and secondary metabolism in plants have been studied, but the signaling pathway which by laser regulates this process remains unclear. Therefore, the current study sought to explore the role of RBOH-dependent signaling in He–Ne laser-induced salt tolerance and elicitation of secondary metabolism in Salvia officinalis. Seeds were primed with He–Ne laser (6 J cm− 2) and peroxide hydrogen (H2O2, 5 mM) and 15-old-day plants were exposed to two salinity levels (0, 75 mM NaCl).ResultsSalt stress reduced growth parameters, chlorophyll content and relative water content (RWC) and increased malodialdehyde (MDA) and H2O2 contents in leaves of 45-old-day plants. After 48 h of salt exposure, higher transcription levels of RBOH (encoding NADPH oxidase), PAL (phenylalanine ammonia-lyase), and RAS (rosmarinic acid synthase) were recorded in leaves of plants grown from seeds primed with He–Ne laser and/or H2O2. Despite laser up-regulated RBOH gene in the early hours of exposing to salinity, H2O2 and MDA contents were lower in leaves of these plants after 30 days. Seed pretreatment with He–Ne laser and/or H2O2 augmented the accumulation of anthocyanins, total phenol, carnasol, and rosmarinic acid and increased total antioxidant capacity under non-saline and more extensively at saline conditions. Indeed, these treatments improved RWC, and K+/Na+ ratio, enhanced the activities of superoxide dismutase and ascorbate peroxidase and proline accumulation, and significantly decreased membrane injury and H2O2 content in leaves of 45-old-day plants under salt stress. However, applying diphenylene iodonium (DPI as an inhibitor of NADPH oxidase) and N, N-dimethyl thiourea (DMTU as a H2O2 scavenger) after laser priming reversed the aforementioned effects which in turn resulted in the loss of laser-induced salt tolerance and secondary metabolism.ConclusionsThese findings for the first time deciphered that laser can induce a transient RBOH-dependent H2O2 burst, which might act as a downstream signal to promote secondary metabolism and salt stress alleviation in S. officinalis plants.

Studies on the physico-chemical properties of semi-organic nonlinear optical (NLO) material: 2-CPPC [2-CNPyH][ClO4]

Semi-organic NLO single crystals 2-cyanopyridinium perchlorate (2-CPPC) were successfully grown by the method of slow evaporation of solvent at room temperature (27 °C) by using acetone as a solvent and of dimension 15×12×3mm3. The powder X-ray diffraction (XRD) of the grown crystal has been investigated. The UV–vis study estimates the transmission range, refractive index, extinction coefficient, band gap, and reflectance of the grown 2-CPPC crystal. The fluorescence spectra of the grown crystal were also recorded. The presence of different functional groups and the vibrational modes were confirmed by using FTIR analysis. The crystal's mechanical properties were studied by a Vickers microhardness tester. Single beam Z-scan technique using He–Ne laser is used to study the third-order NLO properties.

Unveiling underlying mechanism of combined He–Ne laser and UV mutagenesis in Bacillus subtilis CICC 21927: A transcriptomic analysis

Conventional random mutation breeding remains the simplest and most cost-effective approach in enhancing strains in fermentation industry. Nonetheless, extensive research on compound mutagenesis are limited to screening target strains, and few studies on the interaction mechanism of compound mutagenesis factors. Herein, transcriptomic was employed to elucidate the molecular mechanism behind helium-neon (He–Ne) laser and ultraviolet (UV) compound mutagenesis in Bacillus subtilis. Transcriptomic sequencing analysis was conducted on five sample groups (control/CK, UV, laser/LA, UV-laser/UL, and laser-UV/LU), facilitating the statistical comparison of differentially expressed genes (DEGs) across 4 sample relationships (CK-vs-UV, CK-vs-LA, CK-vs-LU, and CK-vs-UL). The DEGs revealed that UV irradiation improved the biosynthesis of pyrimidine nucleotides by upregulating the activity of key enzymes (pyrimidine nucleotides synthetase, pyruvate dehydrogenase, phosphotransferase system (PTS) fructose-specific enzyme), while laser irradiation stimulated metabolism through the regulation of transmembrane transporter activity. Further KEGG enrichment analysis of 1891 DEGs in UV-vs-LU sample relationship unveiled 89 genes significantly enriched in the two-component system, which potentially linked to phytochrome. Moreover, analysis of 784 DEGs in UV-vs-UL sample relationship indicated up-regulation of genes associated with translation, replication, and genetic repair pathways, affirming the laser's induction of UV damage repair mechanisms. Subsequently, 9 pivotal genes (liaS, yvfT, yxdK, cheA, ykoW, uvrC, pcrA, recA, and ruvB) were selected for quantitative reverse transcriptional PCR (qRT-PCR) validation, demonstrating consistent trends with transcriptomic data. Conclusively, our findings unveiled interplay mechanism between UV and laser compound mutagenesis at molecular level, offered valuable insights for mutagenesis mode selection and further elucidation of mutagenesis mechanisms.

Synthesis and growth of organic 2-ethylimidazolium hydrogen diglycolate single crystal for nonlinear optical applications

A single crystal of 2-Ethylimidazolium hydrogen diglycolate (DAEI) has been grown by slow evaporation solution (SEST) technique at 35 °C. The DAEI crystal belongs to a monoclinic crystal system with a P21/c space group. The Hirshfeld surface analysis determined the grown crystal has the highest intermolecular contribution for O..H interaction. The phase purity and various planes (hkl) of the DAEI crystal system were determined by powder X-ray diffraction analysis (PXRD). The functional groups and their different vibrations of DAEI crystal were identified by Fourier transform infrared analysis. The band gap energy value of the DAEI crystal is found to be 5.32 eV. Photoluminescence measurement reveals that the DAEI crystal has green emission. The material shows major weight losses of around 82.45 % in the temperature between 140 °C and 300 °C. The dielectric analyses were carried out for different frequencies (1Hz–1MHz) and different temperatures. The third-order nonlinear optical properties such as refractive index (n2), absorption coefficient (β) and susceptibility (χ(3)) were determined using the Z-scan technique using a He–Ne laser (λ = 632.8 nm).

Dendritic Ag@c-Si structure for influenza A virus detection by SERS and machine learning

The combination of Surface-enhanced Raman Scattering (SERS) method and machine learning algorithms has been successfully demonstrated for the detection and differentiation of influenza A virus in buffer medium. Dendritic Ag nanostructures on single-crystal Si wafer have been proposed as SERS-active substrates, which are fabricated using a low-cost and reproducible AgNO3 reduction method. Depending on the time of Ag deposition, structures of different morphologies were obtained. These structures were studied by spectroscopic ellipsometry (SE). To analyze the spectra obtained by SE, we used the Bruggeman effective medium approximation to determine the volume fraction and height of the metal, the Drude model to describe free electrons, the Tauc-Lorentz model to describe the influence of interband transitions, as well as Lorentz model and Gauss model to describe localized surface plasmon resonance (LSPR). SERS was achieved through LSPR excitation and the presence of “hot spots” in the regions around the tips and in the spaces between close-packed dendritic Ag nanostructures. The sample with the most developed surface is the most promising for SERS, since the spectral position of the LSPR is at 658 nm, which is close to the excitation wavelength of the He–Ne laser. The SERS spectra of influenza A virus in buffer medium are difficult to distinguish, so a machine learning algorithms (principal component analysis and support vector machine) were used to directly classify them. For the sample with the most developed morphology, the detection accuracy of influenza A virus was 76.6 ± 4.2 % at a total protein concentration in the test analyte of 300 μg/ml (according to the Lowry method).

Formirovanie fantomnykh izobrazheniy v volokonno-opticheskom endoskope na osnove rasseyaniya sveta

The possibility of obtaining an object image using a fiber-optic endoscope based on ghost imaging principle is demonstrated experimentally. The endoscope consists of a multimode fiber and includes a radiation source with thermal statistics, which is formed by means of random modulation of He–Ne laser radiation with the help of a phase spatial light modulator. It is shown that after the passage through the fiber, the field preserves the pseudo-thermal statistics. Radiation obtained in this way is used for ghost imaging in transmitted as well as scattered light.

A focused review of visible light therapies for vitiligo.

Vitiligo can be challenging to treat and exhibit an unpredictable clinical course. Phototherapy in the form of visible light can achieve both repigmentation and depigmentation outcomes in vitiligo, with minimal associated adverse events. This review focuses on the mechanistic understandings and clinical outcomes of visible light-based treatments for vitiligo. Articles were retrieved from PubMed starting from May 1965 until August 2023, yielding 496 unique articles. We conducted title, abstract, and full-text screening to identify articles describing the use of visible light (380-750 nm), either as part of combination therapy or as monotherapy, for repigmentation or depigmentation treatment in vitiligo. Twenty-seven articles met inclusion criteria, offering preclinical and clinical data regarding the utilization of helium-neon laser (red light) and blue light-emitting diodes (LEDs) as methods of repigmentation therapy in vitiligo. Preclinical and clinical data on the utilization of Q-switched ruby laser (694 nm) and frequency-doubled (FD) Nd:YAG laser (532 nm) for vitiligo depigmentation therapy were also identified. While limited by small studies and a lack of standardized administration of phototherapy, the evidence for visible light's effectiveness in managing vitiligo is encouraging. Red light therapy using He-Ne lasers and blue light therapy via LEDs can stimulate repigmentation in patients with vitiligo with minimal adverse events. Q-switched ruby and FD Nd:YAG lasers provide viable, visible light depigmentation options, either alone or with topical agents. With limited clinical data, larger studies are needed to validate the efficacy of visible light therapy in treating vitiligo and to better understand its long-term outcomes.

Phytochrome (S): The Main Agent of Action of Low-Intensity He–Ne Laser Radiation on Seeds of Cultivated Plants: A Review

Phytochrome (S): The Main Agent of Action of Low-Intensity He–Ne Laser Radiation on Seeds of Cultivated Plants: A Review

Non-contact online inspection method for the appearance diameter uniformity of chemical fiber filaments

As chemical fiber filaments diameter variation directly affects spinning quality, spinning condition monitoring becomes more and more important in an intelligent manufacturing environment. Firstly, based on the single-slit Fraunhofer diffraction model and the Babinet principle, the non-contact filaments diffraction model is developed to generate diffraction fringe patterns by irradiating chemical fiber filaments with He–Ne laser. Secondly, for the characteristics of diffraction fringe patterns, a segmentation mask window-based diffraction fringe center of gravity extraction method is proposed, and a zero-phase Butterworth low-pass filter is designed and applied to the diffraction light intensity curves to accurately extract the extreme points positions of the adjacent dark fringe and calculate the diameter information. Finally, the non-contact chemical fiber filaments appearance diameter online inspection experiment platform is built to carry out static and dynamic experiments of filaments. The experimental results show that the maximum absolute value of absolute error is less than 1.1 μm for static measurement and less than 10 μm for dynamic measurement.

Hybrid Priming with He–Ne Laser and Hydrogen Peroxide Advances Phenolic Composition and Antioxidant Quality of Salvia officinalis Under Saline and Non-Saline Condition

Hybrid Priming with He–Ne Laser and Hydrogen Peroxide Advances Phenolic Composition and Antioxidant Quality of Salvia officinalis Under Saline and Non-Saline Condition

Z-scan and mechanical analysis of 2-phenyl benzimidazole for optical switching application

The slow evaporation solution growth technique is used to grow single crystals of 2-phenylbenzimidazole (2PBMZ). The crystal belongs to the monoclinic system with space group C2/c, which is revealed through the single crystal XRD. The cutoff wavelength and optical band gap energy of the 2PBMZ crystal were observed at 568 nm and 1.96 ev respectively. The Vickers (Hv) hardness number, yield strength and stiffness constant are calculated, which is found to increase with the applied load. The Z-scan technique with He–Ne laser (632.8 nm) has been used to study the third-order nonlinear optical property of 2PBMZ crystal.

Synthesis, structural, spectral, thermal, and optical characterization of a new curcumin derivative: A promising material for NLO applications

A novel Curcumin derivative 1-(4-chlorobenzoyl)-3,5-bis((E)-3,4-dimethoxybenzylidene)piperidin-4-one (CDMBP) has been synthesized by Claisen-Schmidt condensation and Schotten-Baumann reaction methods. CDMBP single crystal was grown from acetone by slow evaporation method at ambient temperature. The crystal structure of the compound was derived by Single Crystal X-ray Diffraction studies (SCXRD). The title compound CDMBP was crystallized in a triclinic crystal system with a P ͞1 space group. NMR spectral analysis reveals the different types of carbon and proton in the molecular structure of the title compound. The modes of vibrations of different chemical groups were identified using FT-Raman and Fourier Transform Infrared spectral analysis (FTIR). Utilizing the UV–Vis spectrum, the cutoff wavelength and linear optical constants such as the band gap, extinction coefficient, and refractive index were calculated. The Photoluminescence spectrum (PL) has been studied and it shows a high-intensity peak at 504 nm and belongs to the green emission radiation region. Fluorescence profiling of the compound was done to get an outline of the emission features of the excited states with the emission decay mechanisms using Lifetime measurements. The third-order nonlinear optical property (NLO) of CDMBP was investigated in detail using a Z-scan technique with a He–Ne laser at 632.8 nm as a laser source. The nonlinear optical susceptibility (χ3), absorption coefficient (β), and refractive index (n) were calculated using transmittance data. The thermal stability of the grown crystal was investigated from the Thermogravimetric Analysis (TGA) and Differential Thermal Analysis (DTA).

Synthesis, Growth, Thermal and Third‐Order Nonlinear Optical Studies of Bisglycine Lithium Perchlorate Single Crystal

AbstractThe synthesis as well as the results of the investigations on the structure as well as properties ‐ thermal, mechanical, surface and nonlinear optical of semiorganic bisglycine lithium perchlorate (BGLP) single crystals are herein recorded. BGLP single crystal with dimensions 14× 3 × 2 mm3 has been synthesized and its structure and lattice parameters have been identified with the aid of X‐ray diffraction. The vibrational spectrum of BGLP has been investigated making use of FT‐IR and FT‐Raman spectra. Optical transmittance and absorption is examined by UV–vis spectroscopy with thickness 2 mm and it is shown that the crystal is highly transparent with a lower cut‐off of 287 nm. The optical bandgap is evaluated as 5.7 eV. The dielectric constant is found to show variations with frequency as well as temperature, which remains constant at high frequencies. Dielectric loss is found to decrease with the applied electric field. BGLP is manifested to be thermally stable up to 256 °C as revealed from thermogravimetric analyses. The 2D nucleation mechanism in the growth of BGLP crystals is understood from etching studies. By implementing Z‐scan studies with a He─Ne laser as a source, the nonlinear absorption coefficient, susceptibility, and third order nonlinear refractive index are all computed.

Investigations of the L-ornithinium dipicrate nonlinear optical material with an emphasis on very efficient second-harmonic generation in electro-optical and optoelectronic devices

Superior optical fineness and high SHG efficacy LODP crystals were grown using the solution growth approach, which involved slow cooling and slow evaporation methods. The fully developed organic LODP sample crystallized into a monoclinic structure with the noncentrosymmetric space group P21. Along the (1 3 1) track, the seed specimen was cut into pieces for the standard solution growth technique. A single crystal of huge size was completely produced using solubility data and a slow cooling procedure. X-ray diffraction studies on a single crystal were used to determine the unit cell's properties. The produced crystals were characterized using a wide range of techniques, including UV–Vis, dielectric, laser damage threshold (LDT), hardness, and HRXRD experiments to examine their physical and optical properties. The grown LODP largeness crystal has better crystalline fineness and fewer flaws, as exposed by HRXRD and etching studies. The UV–Visible analysis reveals that the SCST-produced LODP crystal has better optical properties than the SEST-grown crystal. When comparing the laser damage thresholds (LDT) of LODP crystals made using SEST and SCST, the latter are shown to be better. Microhardness studies carried out at various temperatures show that crystals grown using the SCST method have more mechanical stability than crystals grown using the SEST method. In contrast to SEST-generated crystals, dielectric dispersion is higher in fully developed SCST-technique crystals. Piezoelectric nature and relative Second Harmonic Generation (for different particle sizes) were also performed. For LODP crystals, third-order non-linear optical properties were obtained through the SEST and SCST techniques using a 632.8 nm He–Ne laser. The powder X-ray diffraction investigation verifies the compound's crystalline form. The existence of LODP components was verified using energy dispersion spectrometry. Thermogravimetric and differential thermal measurements demonstrate the crystal's thermal stability.

An extensive investigation of crystalline, nonlinear, piezoelectric, optical, phase purity and electro-optic properties of doped ammonium dihydrogen phosphate single crystals

Pure single crystals of ammonium dihydrogen phosphate (ADP) and crystals containing 1, 3, and 5[Formula: see text]mol% of itaconic acid (ITA) were generated by the slow evaporation of an aqueous solution. With the help of powder X-ray diffraction and Fourier transform infrared spectroscopy, we were able to show that doping puts a lot of stress on crystals. According to the of Vickers microhardness results, the addition of ITA causes the ADP to have a greater degree of abrasiveness. The SHG efficiency of ITA-doped ADP is greater than that of pure ADP. The presence of dopant was established using the energy-dispersive spectroscopy. The [Formula: see text]-scan method was used to investigate the third-order nonlinear optical characteristics of ITA–ADP crystals formed by the slow evaporation method on a variety of planes. A He–Ne laser with a wavelength of 632.8[Formula: see text]nm was used to carry out the investigation. The nonlinear absorption coefficient, nonlinear refractive index, and third-order nonlinear susceptibility of the ITA–ADP crystals were also plotted in detail. The piezoelectric charge coefficient of pure ADP is lower than that of the ITA-doped ADP. Analysis of the electro-optic investigation reveals lesser half-wave voltage of doped ADP.

Enhancing acid production of Acetobacter pasteurianus by laser and intense pulsed light mutagenesis and its molecular mechanism based on transcriptomic analysis

In this study, novel mutagenesis of He–Ne laser and intense pulsed light (IPL) combined with high-throughput screening (HTS) method were used to mutagenize Acetobacter pasteurianus CGMCC 1.59. The acid production of mutants 1-F-6 (after 50 min of He–Ne laser mutagenesis) and 1-C-1 (after 60 min of IPL mutagenesis) was observably increased by 18.21% and 8.41%, respectively, with reference to CGMCC 1.59 (58.75 g·L−1). Transcriptomics and quantitative real-time PCR (qRT-PCR) results indicated that A-vs-C had 17 differentially expressed genes (DEGs) (15 up-regulated and 2 down-regulated), whereas A-vs-F showed 132 DEGs (58 up-regulated and 74 down-regulated). The annotated signaling pathways were significantly enriched in carbohydrate metabolism, growth, amino acid metabolism, and carbohydrate metabolism. The mutant 1-C-1 only up-regulated the expression of pyruvate metabolism pathways and tricarboxylic acid (TCA) cycle-related genes, while mutant 1-F-6 up-regulated the expression of ethanol oxidation respiratory chain pathway-related genes in addition to alterations in the above pathways. Acetaldehyde dehydrogenase and alcohol dehydrogenase were the main acting enzyme systems in the acetic acid fermentation process, and their up-regulation helped to increase acid production. Also, the enhancement of TCA cycle and oxidative respiratory chain pathways could improve its energy metabolism pathways, thereby promoting the acid production of acetic acid bacteria.

Laser Seed Pretreatment Alters the Silybin Content and Anti-Dictyostelium discoideum Cell Growth Activity of Silybum marianum (L.) Fruit

Silybum marianum is a medicinal plant that produces silybins A and B, which exhibit liver-protective activities. The He–Ne laser pre-sowing seed treatment has been used as a physical biostimulator in numerous plants to promote seed germination, plant growth, and secondary metabolite production. Thus, in this study, a He–Ne laser at 632.8 nm was used to irradiate S. marianum seeds with the aim of promoting plant growth as well as enhancing the production of silybin (A + B). The seeds were irradiated with a He–Ne laser for 2, 4, 6, 8, and 10 min. The growth attributes of the plants, as well as the silybin (A + B) content and bioactivities of fruit extracts from various treatment groups, were compared. The results indicated that all laser seed treatments resulted in a subsequent increase in plant growth, with the highest yield observed in the 10 min laser treatment. An increase in fruit silybin (A + B) content and in chalcone synthase gene expressions were observed in plants from the 6-, 8-, and 10-min laser-irradiated seeds. The highest silybin (A + B) contents were observed in plants from the 6-min-irradiated seeds. Furthermore, the corresponding fruit extract also exhibited elevated cell growth inhibition in the Dictyostelium discoideum cell model.

Effect of fractional laser alone or in combination on alopecia areata: A systematic review and meta-analysis.

Alopecia areata (AA) is characterized by limited non-scarring patchy alopecia, which appears as round or oval patches and is prone to recurrence, causing severe psychological burdens to patients. No specific device has been approved by the FDA for the treatment of baldness, but new treatments are being investigated and treatments such as the excimer laser, He- Ne laser, and excimer lamp have been proposed. A growing number of studies have found that fractional lasers also have great potential in the treatment of AA. A literature search and meta-analysis using Review Manager 5.4 software to investigate the efficacy of fractional laser treatment for AA. Fractional laser combined with minoxidil (RR 1.32, 95% CI 1.17-1.49, p < 0.00001) or cortisol (RR 1.39, 95% CI 1.15-1.67, p=0.00006) was more effective than either drug alone in the treatment of AA. Of course, the fractional laser alone was also effective in the treatment of AA (RR 10.33, 95% CI 2.07-51.36, p=0.004) and more effective than cortisol alone (RR 1.86, 95% CI 1.36-2.52, p < 0.00001), and there was no effect on the occurrence of adverse effects (p=0.49 > 0.05). When compared to other physical treatments of a comparable kind, fractional laser therapy's effectiveness was not significantly different (p=0.15 > 0.05). Our results show that the use of fractional lasers can effectively treat alopecia areata.

Optical nonlinear effects of nickel and cobalt substituents in 1D/2D manganese tungstate/rGO nanocomposite for smart filtering optical radiation

The smart filtering effects of Manganese tungstate/reduced Graphene Oxide (MnWO4/rGO,) and Nickel and cobalt doped Manganese tungstate/reduced Graphene Oxide (Mn(1-x+y)NixCoyWO4/rGO) self-assembled urchin like microspheres are explored. Their relevant optical nonlinearities are related with that of pristine MnWO4 nanorods. The third order optical nonlinearities are characterized by a Z-scan analysis with continuous wave regime of 633 nm (He:Ne laser). The highest nonlinear attenuation is attributed to Mn(1-x+y)NixCoyWO4/rGO (5 wt%) microstructures. The intensity dependent absorption β(m/W) and nonlinear index of refraction n2(cm2/W) is determined to be 4.8×10−4 and 8.8×10−7. The maximum attainable optical susceptibility χTOT3 is 16.8×10−8 esu. The morphology of pristine MnWO4 nanorods and urchin like microstructures is evidenced using HRSEM images. The defect D and optical phonon G bands from the Raman signal besides the Agυ1 modes confirms the materialization as nanocomposite.