Red Radiation Research Articles

Effect of Amino Acids on Folates Accumulation in Wheat Seedlings during Germination under Red Light Radiation.

Deficiency of folates can cause various health problems, and germination is a potential way to enrich folates in grain-based food materials. In the present study, the effects of six amino acids (phenylalanine, tyrosine, tryptophan, glutamate, γ-aminobutyric acid, and p-aminobenzoic acid) on folate accumulation during wheat germination under red light radiation were investigated, and an optimized combination of amino acids for promoting folate enrichment was established. The results showed that applying phenylalanine, tyrosine, tryptophan, glutamate, or p-aminobenzoic acid to wheat seedlings during germination can significantly increase the content of total folates through activating the synthesis of the precursors for folate synthesis (pterin and p-aminobenzoic acid) or condensation of these two moieties. Meanwhile, up-regulation of corresponding genes was observed by measuring their expressions to investigate the mechanism for promoting the accumulation of folates. The highest content of folates (ca. 417 µg/100 g DW) was observed when the germinated wheat was cultured with a mixture of 1.5 mM phenylalanine, 0.5 mM tyrosine, 0.5 mM tryptophan, 0.75 mM p-aminobenzoic acid, and 0.5 mM glutamic acid, which was 50% higher than the control seedlings. This study established a promising and practical approach to enhance the accumulation of folates in wheat seedlings.

The qualities of dyed YAG:Ce3+@SiO2 for WLEDs via energy conversion

Y3Al5O12:Ce3+ (YAG:Ce3+), the most common yellow phosphor for WLEDs, has a red insufficiency in its light spectrum. The Ce3+ spectral profile is modified in this research using surface-located ATTO-Rho101 dye molecules, which have powerful, wide impregnation in the greenish-yellow spectroscopic zone of Ce3+ radiation and vivid red-emitting radiation. To create a spherical shell and evenly dispersed micro and nanometer YAG:Ce3+, a modified solvothermal technique is applied. Surface SiO2 covering and synchronized dye embedding are accomplished using solvothermally generated YAG:Ce3+, temperature-stimulated micro-YAG:Ce3+, plus commercialized phosphorus. Upon blue light excitation, the accumulated YAG:Ce3+@SiO2+dye powder exhibits efficient radiative conversion/reintake from Ce3+ within the internal structure of YAG to the pigment particles from the SiO2 external shell, despite the phosphors' diameter; which likely boosts its red radiation. Fluorescence microscopy would be a suitable way to determine the reabsorption of powdered substances.

Activation of Wnt/β-Catenin Signaling Involves 660 nm Laser Radiation on Epithelium and Modulates Lipid Metabolism.

Research has proven that light treatment, specifically red light radiation, can provide more clinical benefits to human health. Our investigation was firstly conducted to characterize the tissue morphology of mouse breast post 660 nm laser radiation with low power and long-term exposure. RNA sequencing results revealed that light exposure with a higher intervention dosage could cause a number of differentially expressed genes compared with a low intervention dosage. Gene ontology analysis, protein–protein interaction network analysis, and gene set enrichment analysis results suggested that 660 nm light exposure can activate more transcription-related pathways in HC11 breast epithelial cells, and these pathways may involve modulating critical gene expression. To consider the critical role of the Wnt/T-catenin pathway in light-induced modulation, we hypothesized that this pathway might play a major role in response to 660 nm light exposure. To validate our hypothesis, we conducted qRT-PCR, immunofluorescence staining, and Western blot assays, and relative results corroborated that laser radiation could promote expression levels of β-catenin and relative phosphorylation. Significant changes in metabolites and pathway analysis revealed that 660 nm laser could affect nucleotide metabolism by regulating purine metabolism. These findings suggest that the Wnt/β-catenin pathway may be the major sensor for 660 nm laser radiation, and it may be helpful to rescue drawbacks or side effects of 660 nm light exposure through relative interventional agents.

Influence of NaYF4 Inert and Active Layer on Upconversion Luminescence.

NaYF4:Yb,Er@NaYF4 core–shell nanostructures were prepared to investigate their influence on upconversion (UC) luminescence. Tests revealed green radiation (4S3/2→4I15/2) and red radiation (4F9/2→4I15/2) first increased and then gradually decreased as Yb concentration increased in the NaYF4 shell. The strongest fluorescent radiation occurred at an Yb concentration of 5%. To investigate the complicated variation of luminescence, we designed a set of experiments to study the impact of Yb ion concentration on luminescence intensity, and we analyzed the corresponding enhancement mechanism. It is probable that the energy transfers between both Yb and Er ions and Yb and Yb ions are involved in the UC processes. The enhancement of hybrid nanostructures has huge potential in biological detection and solar cells.

Ca9La(PO4)7:Eu2+,Mn2+: a radiation-adjustable phosphor usable for high-perfomance white light-emitting diodes

We used solid-condition processes to make a sequence of radiation-adjustable phosphors Eu2+/Mn2+ co-doped Ca9La(PO4)7 (shortened as CaLa:EM), which show a consistently variable hue from green to yellow and red via an efficient resonance-form energy transition as well as the strength of green and red radiations may be controllable through altering the Mn2+concentration. We examined the transition of energy (Eu2+®Mn2+) for CaLa:EM. It is proved to be a resonant kind using a dipole-quadrupole process, having power shift critical range calculated to be 11.36 Å by using the spectral overlap techniques. Mixing a 365 nm UV-InGaN chip as well as one phosphor combination containing (Ca0.98Eu0.005Mn0.015)9La(PO4)7 in yellow with BaMgAl10O17:Eu2+in blue produced a warming WLED having CIE color coordinates measured at (0.35, 0.31), better CRI value (Ra)measured at 91.5 along with smaller CCT value of 4,496 K.

The excellent dual optical thermometry of the Yb3+, Er3+ doped SrLu2O4

SrLu2O4: Yb3+, Er3+ samples were achieved successfully via a traditional solid-state method at 1450 °C. As 980-nm laser exciting, the UC spectra include red and green emissions mainly centering on 665 and 552 nm, respectively. The red is dominant, and the green part is a relative weakness. For all co-doped samples, intense red radiation is obtained. Meanwhile, the experimental formulas about pumping power and spectrum intensity helped us comprehend the up-conversion processes further, and the conclusion is a two-photon process in UC. The 4S3/2 and 2H11/2 levels ions are thermal coupled energy levels. We also investigated thermometric characteristics of the samples on the fluorescence intensity ration technology. For SrLu2O4: Er3+/Yb3+, it can be used as a temperature sensor by using its green emission and red emission, and the sensor sensitivity was calculated. The maximum absolute sensitivity and the relative sensitivity is 0.00226 K-1 and 0.0119 K−1 at 513 K for green emission and the maximum absolute sensitivity and the relative sensitivity is 0.00126 K-1 and 0.0026 K−1 at 303 K for red emission. The fluorescence intensity ratio (FIR) values are almost stable and accurate in repeated tests. As a result, the SrLu2O4: Er3+/Yb3+ samples would useful hopefully to optical engineering and sensors.

Minimization of the equivalent system mass of a vitamin greenhouse with LED lighting for various scenarios of space missions

To improve the habitat of the manned spacecraft (MS) crews with fresh vitamin greens, relatively small and economical space greenhouses (SG) with LED-based lamps (LED) can be used. In order to reduce the costs of onboard resources when growing plants in SG, the method of adaptive search optimization of the lighting parameters of plants during their growth was used. The minimum specific value of the light-dependent part of the equivalent system mass (ESM) per unit of grown biomass (G) was used as the current optimization criterion for SG. The current value of the criterion at plant age t during period of time Δt can be written as: min G (I, t, Δt) = min{[Cv (k3/k2) + CE (k4/k2)·I]/F(I,t) Δt}. Here F(I,t) - is the current net photosynthesis of the crop; CV,CE – cost factors of consumed by SG electric power unit and unit of volume occupied by the SG, in kg/m2 and kg/kW, respectively; k2-k4 - constants of dimension matching; I – lighting attributes which include combination of parameters (intensity, spectrum, time distribution). If lighting spectrum and time distribution are constant, I will equal to average PPFD. Obviously, the cost coefficients CV, СE can depend both on spacecraft design and on space mission specificity – flight duration, task program, crew number, etc. The CV and CE have been calculated for 3 published scenarios of space missions: for a manned station in low Earth orbit, a planetary mission on a Lunar base and a planetary mission on Mars. Special stand was built for adaptive optimization of crop illumination using the crop net photosynthesis as biofeedback. Chinese cabbage was grown in a phytotron under 24-h lighting per day. Above the crop, an LED lamp was mounted with autonomous regulation of supply currents for LEDs with red (660 nm) and white (color temperature 4000 K) radiation. The crop net photosynthesis was automatically measured every 15 min by the rate of CO2 decrease in the closed phytotron air. The control software and hardware complex calculated the value of the optimality criterion G (t) at the time of measurement and calculated the optimal parameters of the supply currents for red and white LEDs, which were implemented at the next iteration of the search. The optimal lighting dynamics for Chinese cabbage crop in the phytotron, minimizing ESM, was experimentally obtained for the last 7 days of the plants’ growth.

Transcriptome Analysis Reveals Differences in Anthocyanin Accumulation in Cotton (Gossypium hirsutum L.) Induced by Red and Blue Light.

Many factors, including illumination, affect anthocyanin biosynthesis and accumulation in plants. light quality is the key factor affecting the process of photoinduced anthocyanin biosynthesis and accumulation. We observed that the red color of the Upland cotton accession Huiyuan with the R1 mutation turned to normal green color under light-emitting diodes (LEDs), which inspired us to investigate the effect of red and blue lights on the biosynthesis and accumulation of anthocyanins. We found that both red and blue lights elevated accumulation of anthocyanins. Comparative transcriptomic analyses, including Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) and GSEA, revealed that genes differentially expressed under different light conditions were enriched with the pathways of circadian rhythm, phenylpropanoid biosynthesis, anthocyanin biosynthesis, and flavone and flavonol biosynthesis. Not surprisingly, all the major structural genes related to biosynthesis of anthocyanins, including the key regulatory MYB transcription factor (GhPAP1D) and anthocyanin transporter (GhGSTF12), were induced by red or blue light treatment. However, LARs and MATEs related to biosynthesis of proanthocyanidins were more significantly up-regulated by red light radiation than by blue light radiation. Vice versa, the accumulation of anthocyanins under red light was not as high as that under blue light. In addition, we demonstrated a potential role of GhHY5, a key regulator in plant circadian rhythms, in regulation of anthocyanin accumulation, which could be achieved via interaction with GhPAP1D. Together, these results indicate different effect of red and blue lights on biosynthesis and accumulation of anthocyanins and a potential module including GhHY5 and GhPAP1D in regulation of anthocyanin accumulation in cotton. These results also suggest that the substrates responsible the synthesis of anthocyanins under blue light is diverted to biosynthesis of proanthocyanidin under red light.

Photodynamic inactivation (effect of laser with and without photosensitizer) on viability of streptococcus pyogenes

Abstract:
 Burns wounds infection is the high most frequent complications of burns as a result of penetration of bacteria from neighboring tissue. Because of expanded utilization of antibiotics, the spread of multi-drug resistance bacteria emerge as one of alarming hazard to public health.
 Photodynamic inactivation is the technique that can be used to prohibit these organisms. This study focused on bactericidal potency of toluidine blue (TBO) photosensitizer and red laser radiation of 635nm with different doses against multi-drug resistant streptococcus pyogenes (S. pyogenes) isolated from infected burns wounds to see if it is susceptible to photodynamic inactivation .
 A total of 45 isolates were collected from 38 patients with infected burns wounds samples were collected from September to December 2019.Burns wounds swabs were employed using standard procedure of swab collection. Among these, eleven isolates were multidrug resistant S.pyogenes. More resistant isolate that has been proved to all antibiotics used. This multidrug resistant isolate used in all experiments. Bacterial suspension was diluted by using serial dilution. The suspension of S. pyogenes in normal saline was treated with red laser radiation at a wavelength 635nm with and without TBO, and investigated the effect of changing laser doses (3.6 ,7 and 10.8 J/cm2) corresponding to laser exposure time (5,10 and 15 minutes and different photosensitizer concentrations on viability of S. pyogenes isolated from infected burns wounds. The results of this study suggest that multi- drug resistance S pyogenes isolated from infected burns wounds inhibited by using photodynamic inactivation mediated by TBO and red laser at a wavelength 635 nm. The effective technique for killing or inhibiting S. pyogenes isolated from infected burns wounds is the combination of red laser at a wave length 635nm and TBO. Combination of TBO and red laser light prohibit S. pyogenes, the optimum results of bacterial inhibition obtained at 50µg/ml, and laser dose 7 J/cm2 corresponding to exposure time 10 minutes.

INFLUENCE OF RED LASER RADIATION ON THE VIGOR OF TOMATO SEEDS AFFECTED BY AGING

The loss of vigour in tomato seeds (Solanum lycopersicum L.) due to aging is a normal condition. This study provides a future reference in regard to the possible applications pre-sowing of red laser radiation treatments on tomato seeds to improve the vigour of the aged seeds. The objective of the study was to analyse the effects of laser radiation on aged tomato seeds, on the rate of germination and growth. It is hypothesized that at least one treatment of red laser radiation could improve the seed vigour. Two groups of seeds were used, one with 11 years of aging and another with seeds aged 11 years plus 24 h of artificial aging. For the radiation, a red laser diode of 660 nm was used with a potency of 100 mW, at a radiation density of 0.2 mW cm-2, eight exposure times to the laser radiation and a control. The data were subjected to an analysis of variance and the means were compared with the Tukey test (HSD; p ≤ 0.05). In seeds with 11 years of aging, the laser treatment at 120 s improved seed vigour by 125 %, resulting from an increase in the growth of the radicle (167 %, p ≤ 0.05) compared to the control (100 %). On the other hand, the laser treatment at 60 s improved the tolerance to stress from artificial aging, the vigour index increased 143 % compared to the control (100 %), as a result of an improvement in germination of 162 % and in the hypocotyl growth (130 %, p ≤ 0.05), compared to the control (100 %). Red laser radiation on tomato seeds affected by natural or artificial aging can influence the processes of photo morphogenesis and increase seed vigour.

Enhancing optical properties of WLEDs with LaOF:Eu3+&SiO2 application

After many efforts, the core-shell nanostructure of LaOF:Eu3+SiO2 that emits bright red radiation can be fabricated by simple solvothermal application succeeded by heat treatment. The resulted particles from the fabrication process are small in size, able to demonstrate circular form more efficient and prevent stacking. Photoluminescence (PL) emission spectra exhibits intense peaks at 593 nm, 611 nm, 650 nm corresponds to 5D0 -- 7FJ (J = 0, 1 and 2) Eu3+ transitions respectively. The spectral intensity parameters and Eu-O ligand behaviors are estimated by means of Judd-Ofelt (J-O) theory. CIE co-ordinates are found to be (x = 0.63, y = 0.36) which is very close to standard NTSC values (x = 0.67, y = 0.33). CCT value is 3475 K which is less than 5000 K, as a result this phosphor is suitable for warm light emitting diodes. The optimized core-shell SiO2 (coat III)@LaOF:Eu3+ (5 mol%) was used as a fluorescent labeling marker to identity latent fingerprints on both porous and non-porous surfaces. The fingerprints results are highly sensitive, selective and also has no obstruction caused by the back-ground which supports level-I to level-III fingerprint ridge recognition. The experiments outcomes suggest that the enhancements brought by the core-shell NS structure can be further examined to apply in forensic and solid state lightning applications.

Red-light-triggered self-destructive mesoporous silica nanoparticles for cascade-amplifying chemo-photodynamic therapy favoring antitumor immune responses

Although chemo-photodynamic therapy demonstrates promising synergetic therapeutic effects in malignant tumors, the light-controlled drug release, synergism and biocompatibility of current nanocarriers are limited. Herein, we report a red light-responsive, self-destructive carrier constructed using polyethylene glycol-modified, diselenide-bridged mesoporous silica nanoparticles. The carrier is co-encapsulated with the chemo-drug doxorubicin and the photosensitizer methylene blue for chemo-photodynamic therapy. Upon low-dose red light irradiation during photodynamic therapy (PDT), the reactive oxygen species (ROS) mediates a diselenide bond cleavage resulting in the degradation of the organosilica matrix and a dual drug release. This, in turn, results in a synergistic chemo-photodynamic performance in vitro and in vivo. More importantly, such cascade chemo-PDT boosts immunogenic cell death and robust anti-tumor immunity responses. Combination with a PD-1 checkpoint blockade further evokes a series of systemic immunity responses that suppress distant tumor growth and the pulmonary metastasis of breast cancer, as well as offer long-term protection against recurrent tumors. The presented work offers a controllable self-destruction nanoplatform for cascade-amplifying chemo-photodynamic therapy in response to external red light radiation.

Laser therapy effect on endothelial dysfunction in patients after the surgery for orthognathic disorders

To optimize postoperative rehabilitation by applying low-intensity laser irradiation (LILI) with different wavelengths in the early postoperative period to prevent inflammatory complications. After radiological examination and ultrasound diagnostics of the periodontal tissue vessels, surgical methods of orthognathic treatment were performed, after completion of which a course of LILI was carried out. The VEGF its receptors (sVEGF-R1; sVEGF-R2) content was measured by enzyme immunoassay using standard reagent kits. The laser therapy using 635 nm laser light was applied directly to the vestibular and oral surfaces of the gingival tissues and in the operation area, changeable by the scanning method, for 1.5 minutes (5 W power); the pulsed infrared laser therapy (PILT) with the 904 nm wavelength (light pulse duration 100 s, power 15 W, 1500 Hz) applied epicutaneously to the operation projective zones (four control points of the upper and lower jaw) through the skin of the cheek, in stable method (1.5 minutes) with a time range between red and infrared wavelength LILI not exceeding 100 s (1.5 minutes). Vascular and endothelial dysfunction after laser irradiation with different wavelengths is better controlled by increasing the microcapillary blood flow (66.7% gain; p<0.05) in arteriolar and 70.3% in venular sections of capillaries (p<0.01), which is associated by vasodilatation: diameter increased by 26.9% compared to that under the influence of red laser radiation (by 13.0%) and infrared laser radiation (by 7.2%); p<0.01). Early laser therapy using the low-intensity laser irradiation with different wavelengths improves vasoactive processes of hemoregulation in dental tissues associated with the elimination of vasospasm caused by operative stress, activation of arteriolodilatory effects, contributes to the prevention of development of inflammatory complications.

Initiation of lightning flashes simultaneously observed from space and the ground: Narrow bipolar events

We investigate the initiation of four lightning flashes detected from ground by means of the Colombia Lightning Mapping Array (Colombia-LMA) and simultaneously observed from space by the optical sensors of the Atmosphere-Space Interactions Monitor (ASIM) on board the International Space Station (ISS), the Geostationary Lightning Mapper (GLM), and the Lightning Imaging Sensor on the ISS. The initiations of the flashes are characterized by isolated and predominant optical blue pulses (337.0 nm). In three of the flashes, red emissions (777.4 nm), a dominant line of hot lightning, were not detected during their initiation. In these cases, the initiations were also accompanied by bipolar VLF/LF waveform with a narrow short duration (<40 μs) and VHF emissions with high radio frequency power (<269 kW). The detection of the blue emissions without any red luminosity supports that the fast breakdown processes at the flash initiation can be exclusively of streamer nature. The onset of the fourth flash was associated with both blue and red radiation, and with weak narrow bipolar waveform in VLF/LF and low VHF power. The flashes initiated between the midlevel negative and upper positive charge regions. This paper presents and discusses the first fast breakdown processes observed simultaneously from ground by means a Lightning Mapping Array (LMA) and from space during the onset of lightning flashes.

The effectiveness of complex treatment of acute catarrhal mastitis in cows

The article presents data on the study of the therapeutic efficacy of methods for treating cows with acute catarrhal mastitis. The research was carried out on the basis of 2 cattle farms SPK (collective farm) "Kolos" Myasnikovsky district of Rostov region and individual entrepreneur Head of the peasant (farm) farm AA Berekchiyan Myasnikovsky district of the Rostov region, as well as on the basis of the North Caucasian zonal research veterinary institute - a branch of the Federal State Budgetary Institution "Federal Rostov Agrarian Scientific Center". To study the therapeutic efficacy of the treatment regimen for acute catarrhal mastitis, 2 groups of animals (experimental and control) were also formed according to the principle of analogous pairs, 15 animals each. Control cows were injected with the antibacterial drug amoxicillin LA 15% twice with an interval of 48 hours at the rate of 1 ml of the drug per 10 kg of animal body weight. The drug was administered fractionally, divided into 2 injections. The animals of the experimental group were also injected with the semisynthetic antibiotic amoxicillin LA 15% twice with an interval of 48 hours at the rate of 1 ml of the drug per 10 kg of the animal's body weight. The treatment regimen was supplemented by exposing the animal's body to pulsed low-intensity infrared laser radiation with simultaneous exposure to pulsed incoherent infrared and red radiation and a constant magnetic field in the infiltrate area once a day at the rate of 5 minutes per 10 cm2 of the affected area for 5-7 days. In the course of our research, it was found that therapy for catarrhal mastitis using pulsed low-intensity infrared laser radiation with simultaneous exposure to pulsed incoherent infrared and red radiation and a constant magnetic field in the infiltrate area once a day, as well as the semisynthetic antibiotic amoxicillin LA 15% twice with at intervals of 48 hours showed a high degree of effectiveness. This is confirmed by the rapid recovery of the clinical picture, physiological parameters, and morphological data of the blood of experimental animals. The therapeutic efficiency of the proposed method of treatment was 100%, recovery occurred on average in 3.9 ± 0.15 days. The signs of the inflammatory process disappeared gradually, however, by the 3rd day of treatment, the secretion of milk was completely restored and a significant improvement in the condition of the animals was noted.

Radiation Intensity and Quality Affect Indoor Acclimation of Blueberry Transplants

The objectives were to characterize and compare shrinkage (i.e., transplant loss) and growth of tissue-cultured blueberry (Vaccinium corymbosum) transplants acclimated in greenhouses or indoors under 1) different photosynthetic photon flux densities (PPFDs) (Expt. 1); or 2) spectral changes over time using broad-spectrum white (W; 400 to 700 nm) light-emitting diodes (LEDs) without or with red or far-red (FR) radiation (Expt. 2). In Expt. 1, ‘Emerald’ and ‘Snowchaser’ transplants were acclimated for 8 weeks under PPFDs of 35, 70, 105, or 140 ± 5 µmol·m‒2·s‒1 provided by W LED fixtures for 20 h·d−1. In another treatment, PPFD was increased over time by moving transplants from treatment compartments providing 70 to 140 µmol·m‒2·s‒1 at the end of week 4. Transplants were also acclimated in either a research or a commercial greenhouse (RGH or CGH, respectively). Shrinkage was unaffected by PPFD, but all transplants acclimated indoors had lower shrinkage (≤4%) than those in the greenhouse (15% and 17% in RGH and CGH, respectively), and generally produced more shoot and root biomass, regardless of PPFD. Growth responses to increasing PPFD were linear in most cases, although treatment effects after finishing were generally not significant among PPFD treatments. In Expt. 2, ‘Emerald’ transplants were acclimated for 8 weeks under constant W, W + red (WR), or W + FR (WFR) radiation, all of which provided a PPFD of 70 ± 2 μmol·m−2·s−1 for 20 h·d−1. At the end of week 4, a group of transplants from WR and WFR were moved to treatment compartments with W (WRW or WFRW, respectively) or from W to a research greenhouse (WGH), where another group of transplants were also acclimated for 8 weeks (GH). Shrinkage of transplants acclimated indoors was also low in Expt. 2, ranging from 1% to 4%. In contrast, shrinkage of transplants acclimated in GH or under WGH was 37% or 14%, respectively. Growth of indoor-acclimated transplants was generally greater than that in GH or under WGH. Although growth responses were generally similar indoors, plants acclimated under WFR had a higher root dry mass (DM) and longer roots compared with GH and WGH.

Photon avalanche in nanoluminophore obtained by REE silicate evaporation

A bulk phosphor composition Sr2Y6.8YbEr0.2Si6O26 was synthesized. A nanophosphorus in an amorphous state was obtained from this sample by the method of pulsed electron beam evaporation. The spectra of upconversion photoluminescence of bulk and nanosamples were studied. In the field of pumping power of nanosample with 78 mW laser radiation with a wavelength of 980 nm, there is a threshold population of energy levels Er3+. Laser radiation carries out resonant pumping of 4I13/2 → 4F9/2 transition. Then there is an intensive red radiation upon transition 4F9/2 → 4I15/2. A photon avalanche was found in the nanophosphore, at which the intensity of red radiation increases ∼80 times compared to the bulk phosphorus.

Estimation of nominal ocular hazard distance and nominal ocular dazzle distance for multibeam laser radiation.

This paper presents a method of estimation of the nominal ocular hazard distance (NOHD) and the nominal ocular dazzle distance (NODD) for multibeam laser radiation. For the analysis, laser beams propagating in the same optical path (overlapping) but with different wavelength, power, and divergences in two perpendicular planes were assumed. To the authors' best knowledge, such a comprehensive analysis of multiple beams, considering the above parameters, is being presented for the first time. The dazzling possibilities described thus far assumed a single beam of radiation with a circular cross-section. This article also presents the calculation results of the NOHD and the NODD values for three laser beams with wavelengths in the red, green, and blue radiation spectrum with assumed parameters. Similar calculations were also made for a commercial laser source with potential use for laser dazzling. The presented analysis did not take into account the attenuation of radiation by the atmosphere. Moreover, the study provides recommendations on how to design effective, but safe, multiwavelength laser dazzlers.

Rapid and efficient leaf regeneration propagation system for Euonymus bungeanus

Rapid propagation of plants by tissue culture is of great significance for large-scale production, molecular genetics research, and breeding. Currently, a rapid and high-efficient tissue culture protocol for Euonymus bungeanus is needed. To develop a propagation system for this species, we established a new regeneration system from leaves. Callus formation was induced on Murashige and Skoog (MS) medium supplemented with 0.5 mg dm-3 6-benzylaminopurine (6-BA) and 0.5 mg dm-3 &#945;-naphthalene acetic acid (NAA) and the induction rate almost reached 100 % under red radiation within 21 d. The medium for proliferation of adventitious buds comprised of MS medium with 1.0 mg dm-3 6-BA and 0.5 mg dm-3 NAA, and the induction rate within 20 d nearly reached 100 %. When, the adventitious buds were transferred to the rooting medium containing 1/2MS, 2.0 mg dm-3 indole-3-butyric acid (IBA), and 0.05 mg dm-3 NAA, adventitious root formation was achieved within 20 d. Collectively, the rapid and high-efficient regeneration system from E. bungeanus leaves was established, providing useful references for effective mass propagation and it could serve as an enabling technology for future genetic engineering.

Influence of water shortage on apple seedling growth under different radiation composition

Abiotic stresses strongly impair plant development and might impose detrimental effects particularly on seedlings. Irradiance and water deficit are relevant factors, which affect performance of young plants under controlled conditions. In our study, we investigated the influence of water shortage combined with different radiation sources - light emitting diodes (LED) and compact fluorescence lamps (CFL) - on physiological and biochemical parameters of young apple plants. Stress responses were assessed by fluorescence-based indices, while relative water, chlorophyll (Chl), and proline content served as reference parameters. The watering regime had a higher impact on biochemical indicators than the radiation sources. Lower Chl content was determined in plants grown under LED both in control and in water deficit plants. Nitrogen balance index and nitrogen balance index with red radiation excitation showed similar patterns regarding leaf Chl results in relation to the radiation source, being higher under CFL. In contrast, the flavonol index was higher in plants cultivated under LED. Stomatal conductance and maximal photochemical efficiency emphasised a radiation quality effect with higher values for CFL. In conclusion, fluorescence indices related to nitrogen status and flavonol content are promising parameters to sense physiological impairments under the given conditions. However, discrepancies compared to previous studies might be related to the different plant species, the nature of dehydration, and the measuring conditions.