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The difference in the spectral composition of artificial and natural lighting can negatively affect health, as well as lead to a distorted perception of the color of surrounding objects. At the same time, a certain correction of the spectral composition of visible radiation in medical institutions and workplaces has a positive effect on human health, while can be carried lighting control out taking into account the data of personal sensor devices that determine the human condition. The purpose of the research was to select criteria for comparing natural and LED optical and visible radiation by spectral composition and by the visibility of color differences in natural and LED lighting. The effectiveness of the application of known and developed criteria for assessing the difference in the spectral composition of optical and visible radiation from natural and LED sources was investigated, as well as for the visibility of color differences in natural and LED lighting. To minimize the values of criteria are proposed additive and subtractive methods for calculating LED parameters. Their comparison allowed us to conclude that a more complex calculation algorithm, but higher performance for an additive technique than for a subtractive one with the same minimization results.It was found that to simulate the spectral composition of natural radiation using LEDs, it is most effective to use the criteria "standard deviations of the relative differences between the optical and visible spectral components of natural and LED radiation". A comparison of the criteria for the visibility of color differences in natural and LED lighting showed approximately the same effectiveness of using the criteria "small color differences" and "standard deviation by photoreceptors" at the present stage and the prospects for applying the second criterion, provided that its acceptable values are established.

Imaging spectroscopy is emerging as a leading remote sensing method for quantifying plant biodiversity. The spectral variation hypothesis predicts that variation in plant hyperspectral reflectance is related to variation in taxonomic and functional identity. While most studies report some correlation between spectral and field‐based (i.e., taxonomic and functional) expressions of biodiversity, the observed strength of association is highly variable, and the utility in applying spectral community properties to examine environmental drivers of communities remains unknown. We linked hyperspectral data acquired by airborne imaging spectrometers with precisely geolocated field plots to examine the spectral variation hypothesis along a temperate‐to‐boreal forest gradient in southern Québec, Canada. First, we examine the degree of association between spectral and field‐based dimensions of canopy tree composition and diversity. Second, we ask whether the relationships between field‐based community properties and the environment are reproduced when using spectral community properties. We found support for the spectral variation hypothesis with the strength of association generally greater for the functional than taxonomic dimension, but the strength of relationships was highly variable and dependent on the choice of method or metric used to quantify spectral and field‐based community properties. Using a multivariate approach (comparisons of separate ordinations), spectral composition was moderately well correlated with field‐based composition; however, the degree of association increased when univariately relating the main axes of compositional variation. Spectral diversity was most tightly associated with functional diversity metrics that quantify functional richness and divergence. For predicting canopy tree composition and diversity using environmental variables, the same qualitative conclusions emerge when hyperspectral or field‐based data are used. Spatial patterns of canopy tree community properties were strongly related to the turnover from temperate‐to‐boreal communities, with most variation explained by elevation. Spectral composition and diversity provide a straightforward way to quantify plant biodiversity across large spatial extents without the need for a priori field observations. While commonly framed as a potential tool for biodiversity monitoring, we show that spectral community properties can be applied more widely to assess the environmental drivers of biodiversity, thereby helping to advance our understanding of the drivers of biogeographical patterns of plant communities. [ABSTRACT FROM AUTHOR]

This study investigates the effect of continuous blue light (CBL) treatment on quality-related metabolites, focusing on ascorbic acid (AsA) accumulation in hydroponically grown Eruca vesicaria (L.). Plants were subjected to CBL treatment, consisting of 24-h exposure to constant-intensity blue light (48 μmol m−2 s−1) and 12-h exposure to the remaining spectrum (192 μmol m−2 s−1). The activities of key enzymes in AsA biosynthesis and recycling were analyzed, including L-galactono-1,4-lactone dehydrogenase (GalLDh), monodehydroascorbate reductase (MDhAR), dehydroascorbate reductase (DhAR), and ascorbate peroxidase (APX). The results showed a significant increase in AsA accumulation of 65.9% during the “day” and 69.1% during the “night” phases under CBL compared to controls. GalLDh activity increased by 20% during the “day phase” in CBL-treated plants. APX activity also rose significantly under CBL conditions, by 101% during the “day” and 75.6% during the “night”. However, this did not affect dehydroascorbic acid levels or the activities of MDhAR and DhAR. These findings highlight the potential of tailored light treatments to enhance the nutraceutical content of horticultural species, offering valuable insights for sustainably improving food quality in controlled-environment agriculture (CEA) systems and understanding the roles of blue light in ascorbic acid biosynthesis. [ABSTRACT FROM AUTHOR]

Light spectral composition regulates terpenoid biosynthesis, abundances, and chemical diversity in both aboveground and belowground organs, thus impacting the nutritional and medicinal content, aroma, flavor, and color of plants. Red and blue (B) light regulation of terpenoid biosynthesis is mutually dependent, and a light spectrum >50% of red (R) tends to be detrimental to the biosynthesis of various terpenoids. The transcription factor elongated hypocotyl 5 (HY5) plays a central role in UV, R, and B light signaling regulating terpenoid biosynthesis. Beside HY5, MYB and trichome-specific transcription factors play a role in UV light signaling affecting terpenoids. In controlled environment agriculture (CEA), light is used to impact terpenoid production and improve plant quality. In this review we discuss various aspects of light as important regulators of terpenoid production in different plant organs. Spectral quality primarily modifies terpenoid profiles, while intensity and photoperiod influence abundances. The central regulator of light signal transduction elongated hypocotyl 5 (HY5) controls transcriptional regulation of terpenoids under UV, red (R), and blue (B) light. The larger the fraction of R and green (G) light, the more beneficial the effect on monoterpenoid and sesquiterpenoid biosynthesis, and such an effect may depend on the presence of B light. A large fraction of R light is mostly detrimental to tetraterpenoid production. We conclude that light is a promising tool to steer terpenoid production and potentially tailor the quality of plants. [ABSTRACT FROM AUTHOR]

Artificial light can affect eyeball development and increase myopia rate. Matrix metalloproteinase 2 (MMP-2) degrades the extracellular matrix, and induces its remodeling, while tissue inhibitor of matrix MMP-2 (TIMP-2) inhibits active MMP-2. The present study aimed to look into how refractive development and the expression of MMP-2 and TIMP-2 in the guinea pigs' remodeled sclerae are affected by artificial light with varying spectral compositions. Three weeks old guinea pigs were randomly assigned to groups exposed to five different types of light: natural light, LED light with a low color temperature, three full spectrum artificial lights, i.e. E light (continuous spectrum in the range of ~390-780 nm), G light (a blue peak at 450 nm and a small valley 480 nm) and F light (continuous spectrum and wavelength of 400 nm below filtered). A-scan ultrasonography was used to measure the axial lengths of their eyes, every two weeks throughout the experiment. Following twelve weeks of exposure to light, the sclerae were observed by optical and transmission electron microscopy. Immunohistochemistry, Western blot and RT-qPCR were used to detect the MMP-2 and TIMP-2 protein and mRNA expression levels in the sclerae. After four, six, eight, ten, and twelve weeks of illumination, the guinea pigs in the LED and G light groups had axial lengths that were considerably longer than the animals in the natural light group while the guinea pigs in the E and F light groups had considerably shorter axial lengths than those in the LED group. Following twelve weeks of exposure to light, the expression of the scleral MMP-2 protein and mRNA were, from low to high, N group, E group, F group, G group, LED group; however, the expression of the scleral TIMP-2 protein and mRNA were, from high to low, N group, E group, F group, G group, LED group. The comparison between groups was statistically significant (p

Relevance and methodology. In order to determine the effect of increasing the proportion of far red light (different ratio of red and far red light) in the total spectrum of polychrome irradiation on the growth rates of sugar beet plants of the Smena hybrid, they were grown for 82 days under LED lighting under controlled climate conditions in a Synergotron digital device of the ISR 2.01 model with a twofold increase in the proportion of far red light compared to control.Results. An increase in the proportion of far red light led to an increase in the specific weight of leaves with a smaller area of leaves in the initial period of plant growth, higher values of the quantum yield of photosynthesis, the rate of electron transport, and a decrease in energy losses mainly to heat. The biometric indicators of plants changed depending on the period of ontogeny. In the initial period, the biomass of the aerial part prevailed, in the subsequent period, the biomass of root crops. In the experimental variant, the accumulation of biomass in the aerial parts of plants in the initial period of the experiment turned out to be less than in the control, and only at the end of the experiment was an excess of the total biomass in the experimental variant by 12.2%. There was an increase in the accumulation of root biomass compared to the control by 38.7%. The predominant part of the aboveground biomass of sugar beet was made up of leaf blades, the proportion of petioles was much less and practically did not depend on the composition of the light. At the end of the growing period, the dry matter content in root crops increased by 2.44% compared to the control, sugar content – by 0.65%. The data obtained can be used in the development of technology for artificial lighting of sugar beets when grown in closed agrobiotechnosystems in order to increase the yield and sugar content of root crops.

Silvopastoral systems can have animal welfare and sustainability benefits because trees continually remove carbon from atmosphere, reducing greenhouse effects. Thisstudy identified the most promising fruit trees for inclusion in silvopastoral systems to dairy cattle calves. This experiment was conducted at Embrapa Agrossilvipastoril, Brazil, between 2014 and 2018. Five silvopastoral systems with fruit trees and 'Tifton-85' grass were designed to evaluate tree growth and light environment under the canopies. Data were analyzed using SAS® and PDIFF (P < 0.10). Caja fruit trees had the greatest tree height (5.4 m) and trunk diameter (23.4 cm), while acerola fruit tree had the smallest (1.8 m and 8.3 cm, respectively). At 42 months (drought 2017), caja, cashew, and guava trees had similar heights. Guava trees had the highest light interception (89.3%), both cashew cultivars provided medium levels of shade (50 to 60% LI) and with greater constancy between the rainy and dry seasons. The systems that showed increased light interception during the drought period were those with CCP76 in 2017 and EMB51 in 2018. Higher incidences of wavelengths of the spectral composition of light occurred between the rainfall (2015) and drought (2017) periods, and greater differences in the ratio of red:far red in 2015. By 2018, there were no more differences between the rainy and dry seasons for the spectral composition of light under the tree canopies. Cashews and guava trees have adequate growth and light environment to support silvopastoral systems but Caja and acerola fruit trees showed limitations. [ABSTRACT FROM AUTHOR]

This paper investigated latitudinal and seasonal variations in the qualitative characteristics of solar radiation (spectral composition, position of the maximum and short-wave boundary) in the ultraviolet and visible regions. It has been established that, depending on the latitude and season, the peaks λ=415 nm, λ=480 nm, λ=500-505 nm, λ=525-535 nm, λ=575-590 nm, λ=610-700 nm, λ=722.5 nm, λ=735 nm, λ=740 nm, λ=760 nm and λ=765 nm may appear. Coloring surfaces variants whose absorption spectrum corresponds to these peaks are considered. It has been suggested that the coloration of the corolla in flowering plants is the result of adaptation to the solar spectrum maximum and may determine convergent seasonal and latitudinal coloration in species of flowering plants.

This study investigates the effect of continuous blue light (CBL) treatment on quality-related metabolites, focusing on ascorbic acid (AsA) accumulation in hydroponically grown Eruca vesicaria (L.). Plants were subjected to CBL treatment, consisting of 24-h exposure to constant-intensity blue light (48 μmol m−2 s−1) and 12-h exposure to the remaining spectrum (192 μmol m−2 s−1). The activities of key enzymes in AsA biosynthesis and recycling were analyzed, including L-galactono-1,4-lactone dehydrogenase (GalLDh), monodehydroascorbate reductase (MDhAR), dehydroascorbate reductase (DhAR), and ascorbate peroxidase (APX). The results showed a significant increase in AsA accumulation of 65.9% during the “day” and 69.1% during the “night” phases under CBL compared to controls. GalLDh activity increased by 20% during the “day phase” in CBL-treated plants. APX activity also rose significantly under CBL conditions, by 101% during the “day” and 75.6% during the “night”. However, this did not affect dehydroascorbic acid levels or the activities of MDhAR and DhAR. These findings highlight the potential of tailored light treatments to enhance the nutraceutical content of horticultural species, offering valuable insights for sustainably improving food quality in controlled-environment agriculture (CEA) systems and understanding the roles of blue light in ascorbic acid biosynthesis.

Relevance and methodology. In order to determine the effect of near-ultraviolet radiation with a wavelength of 380 nm on the growth and development of a sugar beet hybrid plant, Smena was grown for 82 days under LED lighting with phytolamps and under conditions of increased UV-A intensity of the light range (an increase in the UV/PPFD ratio (0.027) compared with the control (0.0075) while maintaining the ratio of the remaining sites spectrum). The study was carried out on the basis of the digital software package "Synergotron" with a controlled internal environment.Results. An increase in the share of UV-A in the illumination spectrum leads to a significant change in the biometric indicators of plants – the aboveground biomass increases by 2.2 times compared to the control, and the mass of the underground part (root crops), on the contrary, decreases by 86.9%. At the same time, the share of root crops in the total biomass of plants decreases from 60% in the control to 30%. The morphological structure of the leaf apparatus changes: the proportion of petioles increases significantly compared to leaf blades (64.8% of petioles in aboveground biomass, whereas in the control 30%). Probably, an increase in the share of UV-A in the spectrum can favorably affect the cultivation of leaf forms of beets and other root crops. UV-A radiation leads to a change in the chemical composition of root crops, in particular, a decrease in the accumulation of dry substances (by 1.58%) and a decrease in sugar content (by 1.8%). An increase in the proportion of UV-A in the irradiation spectrum changes the parameters of chlorophyll fluorescence and contributes to an increase in the maximum quantum yield of Fv/Fm, non-photosynthetic quenching of NPQ fluorescence and a decrease in the real quantum yield of photosynthesis Y(II), as well as the electron transport rate (ETR).

The article examines a number of features of energy processes in the "three-phase traction electromagnetcapacitor" system with continuous oscillatory motion of the armature electromagnet. It is assumed that the amplitude of mechanical vibrations can be quite large. According to this judgment, regarding the possibility of obtaining low-frequency mechanical oscillations in the range (0÷20) Hz using a three-phase electromagnetic traction system, it should be considered appropriate to consider in detail the processes in the specified device when it is connected according to circuits with series capacitors in a standard network. Such consideration would make it possible to clarify the design conditions of these devices, which helps to improve their design. [ABSTRACT FROM AUTHOR]

The mechanisms of self-oscillation processes occurring in cavities of open flow type are considered and substantiated on the basis of a detailed investigation of the phenomena of hydrodynamic, flow-rate, wave, and resonance nature. The theoretical conclusions are substantiated by an analysis of the data of numerical experiments performed by different authors. [ABSTRACT FROM AUTHOR]

Background and aim: Wherever sunlight reaches litter, there is potential for photodegradation to contribute to decomposition. Although recent studies have weighed the contribution of short wavelength visible and ultraviolet (UV) radiation as drivers of photodegradation, the relative importance of each spectral region across biomes and plant communities remains uncertain. Methods: We performed a systematic meta-analysis of studies that assessed photodegradation through spectrally selective attenuation of solar radiation, by synthesizing 30 published studies using field incubations of leaf litter from 110 plant species under ambient sunlight. Results: Globally, the full spectrum of sunlight significantly increased litter mass loss by 15.3% ± 1% across all studies compared to darkness. Blue light alone was responsible for most of this increase in mass loss (13.8% ± 1%), whereas neither UV radiation nor its individual constituents UV-B and UV-A radiation had significant effects at the global scale, being only important in specific environments. These waveband-dependent effects were modulated by climate and ecosystem type. Among initial litter traits, carbon content, lignin content, lignin to nitrogen ratio and SLA positively correlated with the rate of photodegradation. Global coverage of biomes and spectral regions was uneven across the meta-analysis potentially biasing the results, but also indicating where research in lacking. Conclusions: Across studies attenuating spectral regions of sunlight, our meta-analysis confirms that photodegradation is a significant driver of decomposition, but this effect is highly dependent on the spectral region considered. Blue light was the predominant driver of photodegradation across biomes rather than UV radiation. [ABSTRACT FROM AUTHOR]

This paper investigated latitudinal and seasonal variations in the qualitative characteristics of solar radiation (spectral composition, position of the maximum and short-wave boundary) in the ultraviolet and visible regions. It has been established that, depending on the latitude and season, the peaks λ=415 nm, λ=480 nm, λ=500- 505 nm, λ=525-535 nm, λ=575-590 nm, λ=610-700 nm, λ=722.5 nm, λ=735 nm, λ=740 nm, λ=760 nm and λ=765 nm may appear. Coloring surfaces variants whose absorption spectrum corresponds to these peaks are considered. It has been suggested that the coloration of the corolla in flowering plants is the result of adaptation to the solar spectrum maximum and may determine convergent seasonal and latitudinal coloration in species of flowering plants. [ABSTRACT FROM AUTHOR]

The Mohorovičić discontinuity, often known as the Moho, marks the boundary separating the Earth's crust from the mantle. Techniques such as isostatic-gravity and seismic methods can be used to determine this division. The Moho marks the boundary between the continental and oceanic crust and the upper mantle. Simply put, the Moho acts as a physical/chemical boundary between the mantle and the crust and causes significant changes in geophysical properties such as seismic wave velocity, density, pressure, and temperature (Mooney and Masters, 1998; Martinck, 1994; Bagherbandi, 2011 and Dashtbazi et al., 2023). An accurate and high resolution Moho depth model in fields such as geodesy, geology, geophysics, geodynamic modeling, seismic risk assessment, stress field modeling caused by mantle convection (Li et al., 2018; Behr et al., 2022; Singh and Yadav, 2023; Heilman and Becker, 2022; Hashima et al., 2016; Eshagh et al., 2020; Eshagh, 2015 and Gido et al., 2019), and understanding seismic source mechanisms is important, among other applications (Gido et al., 2019 and Dashtbazi et al., 2023). Furthermore, a reliable Moho model can reveal details of crustal structure that provide valuable insights into the complexities of deeper mantle layers; related to the calculations and detailed examination of gravity, geothermal, geomagnetic models (Stalk et al., 2013). Although there are several Moho models, their accuracy and resolution are insufficient in the complex tectonic geometry of the Makran subduction zone (Brizi et al., 2021 and Heilman and Becker, 2022), because these zones show a complex Moho configuration (Shad Manaman et al., 1390; Taghizadeh Farhamand et al., 2015 and Dashtbazi et al., 2023). As a result, the existing models lack the necessary accuracy for the Makran subduction zone, a region approximately 1000 km long located in southeast Iran and southwest Pakistan (Byrne et al., 1992; Shad Manaman et al., 1390, Penney et al., 2017; Dashtbazi et al., 1398; Dashtbazi. et al., 2023). In geophysical and geodetic studies, hybrid methods are mainly used to determine the Moho depth when seismic data with appropriate distribution and abundance are not available. These techniques include the Parker-Oldenberg method and the Wenning-Mines-Moritz method. In an effort to strengthen the existing Moho depth models in the Makran subduction zone, two distinct models named BC and SC through the integration of gravity (VMM) and seismic (CRUST1.0) data, which are processed through the Butterworth filter, spectral combination approaches and the least squares technique, was developed (Bagherbandi, 2011 and Dashtbazi et al., 2023). The resulting models provide a resolution of 5' x 5' degrees of arc, corresponding to a grid size of 9 x 9 km (Dashtbazi et al., 2023). The accuracy of these models was evaluated against four separate regional and local models. The resulting RMS values were 5.28, 1.55, 4.18, and 1.27 km for the BC model and 5.59, 1.17, 3.74, and 3.04 km for the SC model. Also, the Moho depth model obtained for the west Makran region in Iran significantly improved the accuracy and resolution of the Moho depth models in the studied area. The SC Moho model exhibits improved RMS metrics compared to the combined BC model, so we recommend it as the first priority. While the Moho depth models in our research really bring significant improvements to the existing models of the Makran subduction Moho zone, the integration of more detailed seismic data with SC and BC Moho models can improve the developed model for the Makran subduction zone. In the end, we suggest that a similar approach be adopted for the analysis of the Moho model in the eastern Makran region in Pakistan, which allows a comparative evaluation of the Moho depth and structure between the western and eastern parts in order to obtain a better picture of the Moho depth model of the Makran subduction zone. [ABSTRACT FROM AUTHOR]

Summary: Wind‐induced movement in the canopy produces rapid fluctuations in irradiance, called 'windflecks'. They create a dynamic environment for photosynthesis that bears little resemblance to the stable controlled conditions under which plants are typically measured.We recorded time series of irradiance to assess the diversity of windfleck properties (intensity, duration, frequency, clustering, and spectral composition) in canopies of four crops and five tree species. We also measured traits associated with leaf morphology and canopy architecture, which could be associated with canopy‐specific differences in windflecks.Distinct features of windfleck properties were identified both between and among crop and tree canopy. Windflecks in crops were generally more intense and longer, and baseline irradiance was much higher than even the peak irradiance during a windfleck in a forest. The change in spectral composition during a windfleck was species‐specific. Overall, irradiance fluctuations were less frequent and less intense in tall canopies and with increased depth from the canopy.Our systematic exploration of how canopy structure dictates light dynamics provides new insight into windfleck creation. Coupled with progress in elucidation of the mechanisms of photosynthetic induction, this knowledge should improve our capacity to model canopy ecophysiology and understand light use efficiency in shade. [ABSTRACT FROM AUTHOR]

Purpose: To develop a wearable, spectacle‐mounted, sensor‐based device to monitor and modify myopia risk factors in children, namely near‐working distance, light levels and spectral composition. Methods: A wearable, spectacle‐mounted device has been developed, which consists of inbuilt sensors, namely: (i) light sensor to detect ambient light intensity; (ii) proximity sensor to measure near‐work distance; (iii) microspectrograph to measure spectral power for six visible channels, namely red, green, blue, yellow, orange and violet and (iv) a global positioning system tracker to track the location and the device. The sensors were programmed by Arduino Nano, and the circuit was fixed onto a printed circuit board fitted onto a spectacle frame for pilot testing. Laboratory testing of the prototype was performed using a mannequin. An alert will be set when exceeding the predetermined threshold to help control myopia risk factors. Results: The indoor and outdoor light levels measured using the prototype were less than and greater than 1000 lux, respectively. The actual target distance and the corresponding distance measured by the prototype were highly correlated (R2 = 0.99). The mean distance measured by the prototype was within 1.5 cm of the actual target distance for distances between 30 and 95 cm. The spectral energy of the indoor location was highest for the orange channel at about 100–160 counts/μW/cm2, whereas it was highest for the blue channel in outdoor daylight (10,000–19,000 counts/μW/cm2). Conclusion: A working prototype that can simultaneously measure the viewing distance, light intensity and spectral composition has been developed. [ABSTRACT FROM AUTHOR]

Purpose: Given the possible role of spectral composition of light and myopia, this study aimed at investigating the variation in the spectral composition of ambient light in different (a) outdoor/indoor locations, (b) time of a day and (c) seasons. Methods: The spectral power distribution (SPD), categorised into short (380–500 nm), middle (505–565 nm) and long wavelengths (625–780 nm), was recorded using a handheld spectrometer at three outdoor locations ('open playground', 'under shade of tree' and 'canopy') and three indoor locations ('room with multiple windows', 'closed room' and 'closed corridor'). Readings were taken at five different time points (3‐h intervals between 6:30 and 18:00 hours) on two days, each during the summer and monsoon seasons. Results: The overall median SPD (IQR [25th‐75th percentile] W/nm/m2) across the three outdoor locations (0.11 [0.09, 0.12]) was 157 times higher than that of the indoor locations (0.0007 [0.0001, 0.001]). Considerable locational, diurnal and seasonal variation was observed in the distribution of the median SPD value, with the highest value being recorded in the 'open playground' (0.27 [0.21, 0.28]) followed by 'under shade of tree' (0.083 [0.074, 0.09]), 'canopy' (0.014 [0.012, 0.015]) and 'room with multiple windows' (0.023 [0.015, 0.028]). The relative percentage composition of short, middle and long wavelengths was similar in both the outdoor and indoor locations, with the proportion of middle wavelengths significantly higher (p < 0.01) than short and long wavelengths in all the locations, except 'canopy'. Conclusion: Irrespective of variation in SPD values with location, time, day and season, outdoor locations always exhibited significantly higher spectral power than indoor locations. The relative percentage composition of short, middle and long wavelengths of light was similar across all locations. These findings establish a foundation for future research to understand the relationship between spectral power and the development of myopia. [ABSTRACT FROM AUTHOR]

The libRadtran radiative transfer model was used to calculate examples of the amount of spectral radiation (250–2500 nm) incident on the eye. Simulations were run for every hour of four individual days (representing spring, summer, autumn and winter) and at three latitudes (from southern Spain to central Finland), in order to demonstrate diurnal and seasonal variations in directional photon flux density due to solar angle. The dataset also includes outputs under strong and weak aerosol optical density, three bidirectional reflectance distribution functions (corresponding to a forested, urban and snowy ground surfaces), eight cardinal directions, and two tilt angles (either looking towards the horizon or 15° downward). All simulations were parametrized according to local meteorological conditions (elevation, pressure, temperature) and atmospheric condition on the simulated day (aerosol optical density, water column, O3 and NO2 concentrations), at 170 cm above the ground (representing the average human height). Example data are presented for a 17° field of view relevant to exposure of the macula (without correction for spectral transmission of ocular media). For each simulation, a file in “.csv” format is available containing the radiance at each wavelength. The simulations were performed in batches via R software, from a template input parameter file modified for each simulation from a summary input table. The R code and input files are also available. By describing the amount and wavelength composition of directional radiation incident on the eye, this dataset and future simulations will help parameterize research aimed at understanding and mitigating eye-related diseases.

Artificial light at night (ALAN) is a widespread human-induced disturbance, whose effects have been documented in many ecosystems. However, limited attention has been given to the source of the lights behind ALAN, so this study examined three of them: High-Pressure Sodium (HPS) lamps and warm and cool white Light-Emitting Diodes (LEDs). Laboratory experiments compared the effects of each type of light to natural day/night conditions, upon the activity, feeding behavior and growth of the isopod Tylos spinulosus. Tanks equipped with actographs monitored locomotor activity, while separate tanks were utilized to assess food consumption and growth under natural and ALAN conditions. Our results show that all ALAN sources disrupt and reduce isopods' activity and feeding behavior, with cool and warm LEDs being the most severe and mildest, respectively. Instead, ALAN had only minor effects on isopod growth. Our findings suggest that warm LEDs may be preferable for ALAN mitigation purposes. • ALAN spectral composition affects isopod's activity patterns and feeding behavior. • Cool LEDs severely disrupt activity and feeding compared to warm LED and HPS lights. • Warm LEDs show potential for mitigating ALAN effects on sandy beach ecosystems. • Studies on the effects of ALAN properties on species are essential for informed management. [ABSTRACT FROM AUTHOR]

Forest regeneration is a crucial ecological process for promote self-reproduction and restoration, which is essential for maintaining complex community structure and preserving biological resources. Although sunlight have been considered as the main driver of forest regeneration, how light quality shapes functional traits of seedlings is poorly understood in the forest understorey, where spectral compositions of solar radiation change dramatically. We investigated the responses of 15 typical functional traits of Pinus koraiensis and Quercus mongolica to five filter treatments that differed in the spectral transmittance: (a) 95 % of solar radiation was transmitted (280–700 nm); (b) ultraviolet (UV)-B radiation was attenuated (>315 nm); (c) all UV radiation was attenuated (>400 nm); (d) all UV radiation and blue light was attenuated (>500 nm); (e) all UV radiation, blue-green light was attenuated (>580 nm). Our results showed that functional traits responded to UV-B radiation (contrasting treatment [a] vs. [b]) with species-dependence, but consistently showed a positive response to blue light (contrasting treatment [c] vs. [d]). UV-B radiation decreased the relative growth rate (RGR) and leaf area ratio (LAR) of P. koraiensis seedlings by 48 % and 42 %, respectively; however, it increased seedling height, total leaf area (TLA), and above-ground biomass of Q. mongolica. Blue light consistently increased LAR and RGR of two species. Furthermore, Q. mongolica was more plastic in morphological traits (including plant height and TLA) and root/shoot ratio than P. koraiensis to the single spectral region (UV-B, UV-A, blue, and green light), but opposite in physiological and biochemical traits (such as chlorophyll and anthocyanidin). These suggest that two studied species have evolved different light capture strategies in the understorey: Q. mongolica seedlings tended to adjust morphology and biomass allocation to enhance light interception capacity, while P. koraiensis seedlings preferred to adjust physiological and biochemical traits to enhance light utilization efficiency. A better understanding how canopy spectral compositions affect seedling regeneration may provide a new insight for future forest management (i.e. the appropriate gap creation or tree species combination). • P. koraiensis and Q. mongolica seedlings had a consistent positive response to blue light, while exhibiting opposite responses to UV-B radiation. • Q. mongolica enhanced its light interception capacity by adjusting morphological traits. • P. koraiensis improved its light utilization efficiency through adjusting physiological and biochemical traits. • Differentiation in light capture strategies between species would provide a new insight for forest management to promote the understorey regeneration. [ABSTRACT FROM AUTHOR]

The purpose of the study was to investigate the effect of artificial light with different spectral composition and distribution on axial growth in guinea pigs. Three-week-old guinea pigs were randomly assigned to groups exposed to natural light, low color temperature light-emitting diode (LED) light, two full spectrum artificial lights (E light and Julia light) and blue light filtered light with the same intensity. Axial lengths of guinea pigs’ eyes were measured by A-scan ultrasonography prior to the experiment and every 2 weeks during the experiment. After light exposure for 12 weeks, retinal dopamine (DA), dihydroxy-phenylacetic acid (DOPAC) levels and DOPAC/DA ratio were analyzed by high-pressure liquid chromatography electrochemical detection and retinal histological structure was observed. Retinal melanopsin expression was detected using Western blot and immunohistochemistry. After exposed to different kinds of light with different spectrum for 4 weeks, the axial lengths of guinea pigs’ eyes in LED group and Julia light group were significantly longer than those of natural light group. After 6 weeks, the axial lengths in LED light group were significantly longer than those of E light group and blue light filtered group. The difference between axial lengths in E light group and Julia light group showed statistical significance after 8 weeks (p

In natural environments, the spectral composition of incident light is often subject to drastic changes due to the abundance of suspended particles, floating animals, and plants in coastal waters. In this study, after four months of culturing under blue light (NB), orange light (NY), dark environment (ND), and natural light (NN), the shell length and weight-specific growth rate in Pacific abalone, Haliotis discus hannai, were ranked in the following order: NY > NN > ND > NB. To understand the growth differences in abalone under these different light environments, we first performed 24-h video monitoring and found that the cumulative movement distance and duration were lowest in group NB, whereas the cumulative movement distance and duration were significantly higher in group ND than in any other group (P NN > ND > NB. According to in situ hybridization analysis, the three subtype genes were widely expressed in the hepatopancreas. Finally, the contents of many lipid metabolites differed significantly among groups and the expression levels of the triglyceride hydrolysis-related gene hormone sensitive lipase and fatty acid oxidation-related gene carnitine palmitoyltransferase 1 were higher in groups ND and NB than in groups NN and NY according to fluorescence quantification PCR (P

Results of the spectral analysis of electromagnetic signals induced in a model antenna by discharges from an artificial thunderstorm cell involving structural elements made of dielectric and composite materials are presented. The spectral analysis has been performed using the "Mexican Hat" basic wavelet. The influence of the curvature radius of the tip of the initiating model electrode contacting the surface of the dielectric structure on the spectral composition of the induced signals is investigated. The spectral composition of the discharge current during the formation of a streamer corona with a larger radius of tip curvature exhibited characteristic frequencies with higher values that are several times higher. The spectrum of the signal induced on the antenna contains characteristic frequencies that are higher than those in the discharge-current spectrum. The characteristic frequencies of the signal detected by the antenna during the formation in the electric field of a streamer corona and the upward leader from the initiating electrode with a small radius of curvature in contact with the insulator surface were 20% higher than those in the case when the discharge developed from an electrode with a large radius of curvature. During the formation of the main stage of the discharge, the average values of the maximum frequencies of the signal induced in the antenna had similar values. The frequency that corresponds to the maximum intensity of the signal wavelet spectrum tends to decrease with an increase in the steepness of the streamer corona current pulse. In analyzing the possible effects of atmospheric electricity and lightning on elements of monitoring and control systems of power facilities, it is necessary to take into account that the electromagnetic radiation spectrum of discharges developing from structural elements near the surface of composite/dielectric materials includes frequencies up to 70–80 MHz. [ABSTRACT FROM AUTHOR]

This study examined the effect of different spectral on the growth, feeding rate, digestion, and metabolism of Plectropomus leopardus in an industrial recirculating aquaculture system. All Plectropomus leopardus (wet weight 100 g ± 0.45 g) were kept in triplicate tanks for 60 days under six different spectral full visual (400 to 800 nm), blue (450 nm), green (530 nm), yellow (590 nm), red (630 nm) spectrum, and dark. After the experiment, fish were weighed and sampled to obtain haemolymph, brain, and hepatopancreas tissues, which were used to analyze biochemical parameters and gene expression. The findings indicated that the group exposed to blue light demonstrated substantially elevated feeding rate, weight gain, specific growth rate, and reduced feed conversion ratios and visceral-somatic indexes compared to the other groups (p < 0.05). The blue light and full spectrum groups had considerably increased levels of digestive, metabolic, and antioxidant enzyme activity compared to the other groups (p < 0.05). The expression levels of GH , GHR , PACA , ADCY , IGF I , IGF IR, and IGFBP growth axis genes in the brain and liver were significantly higher in the blue light group than in the other groups (p < 0.05). The results indicate that spectral impact the growth, feeding rate, digestion, and metabolism of P. leopardus. This study revealed distinct spectra that enhanced the growth rate and increased the weight gain from feeding. Furthermore, the optimal spectral composition for recycling aquaculture of P. leopardus was clarified, thereby providing theoretical references for designing lighting strategies in indoor recycling aquaculture systems tailored to P. leopardus. • Blue light can increase the feeding rate and reduce the feed coefficient of P. leopardus. The blue light environment can stimulate the hypothalamus to secrete neuroendocrine factors, including PACA, ADCY, and GnRH, thereby promoting pituitary secretion of GH. This, in turn, triggers the liver to secrete IGF I, promoting the growth of P. leopardus. • Blue light can enhance the activity of immunoenzyme and antioxidant enzyme, and enhance the immune and antioxidant capacity of P. leopardus. At the same time, the activities of some antioxidant enzymes were decreased under blue light, indicating that the environment without pressure under blue light was more conducive to the survival of P. leopardus. [ABSTRACT FROM AUTHOR]

Relevance and methods. We studied the influence of LED lighting of different spectral composition on the content of photosynthetic pigments in tomato leaves to identify the most optimal lighting option suitable for obtaining high-quality seedlings under controlled conditions. We used LED lamps in which the ratio of the photon flux density (PFD) of the orange-red band (607–694 nm) to the PFD of the blue band (400–495 nm) varied from 1 to 20. In this case, the proportion of the PFD in the range 580-607 nm ( yellow) ranged from 13 to 22%, and the fraction of photons in the range 495–580 nm (green) ranged from 18 to 38%. The research was carried out with two varieties of Belarusian tomato varieties, which differed in a number of morphobiological characteristics.Results. It was found that the use of LED lighting of different spectral composition had mainly an inhibitory effect on the biosynthesis of chlorophylls and carotenoids in the leaf tissue of plants. The decrease in the amount of pigments, in comparison with the control variant, reached 47-57%. It was revealed that under all studied lighting options, with the exception of conditions where the spectral ratio R / B ("red/blue") was 0.8, the value of the total inhibitory effect in the Cherry Coral variety was 1.2-1.7 times lower than that of the Zorka variety, which indicated a significantly lower susceptibility of the pigment fund of the former to LED lighting. The smallest inhibitory effect of the latter on the biosynthesis of photosynthetic pigments in both tomato varieties was established at a photon flux of 69.1 μmol/s, while the greatest, exceeding it by 3.0-3.1 times in the Zorka variety and 4.5-5.3 times for the Cherry Coral variety with a photon flux of 73.9 μmol/s.

Tabor RA, Perkin EK, Beauchamp DA, Britt LL, Haehn R, Green J, Robinson T, Stolnack S, Lantz DW, Moore ZJ. 2021. Artificial lights with different spectra do not alter detrimental attraction of young Chinook salmon and sockeye salmon along lake shorelines. Lake Reserv Manage. 37:313–322. Artificial light at night (ALAN) is common in lakes with developed shorelines, especially prevalent in the nearshore areas where juvenile fishes, including salmonids, are present. One concern is that fishes may be attracted to ALAN and become more vulnerable to predators. The use of longer wavelength lights has been suggested to reduce the effects of ALAN; however, the response in juvenile salmonids is not well known. We tested the hypothesis that longer wavelength lights would attract fewer subyearling Chinook salmon (Oncorhynchus tshawytscha) and sockeye salmon (O. nerka) than shorter wavelength lights. Test lights included 4 LED lights, an incandescent light, and a high-pressure sodium light (HPS). In total, 13 experimental trials were conducted in 2017 and 2018, and in total 1769 Chinook salmon and 870 sockeye salmon were collected with beach seines. The mean catch rate (number per beach seine set) of subyearling salmonids was 51.0 for lighted treatments but only 6.6 for control treatments (no light). In both years, we did not find any significant difference in catch rates for either species between either of the longer wavelength lights (red-filter and yellow-filter LED lights) and other lights, and thus we rejected the hypothesis that longer wavelength light would attract fewer subyearling salmonids. For these early life stages of salmon in shallow shoreline habitats, reducing the intensity of light present is likely more important than altering the spectral composition when trying to minimize maladaptive attraction to ALAN. [ABSTRACT FROM AUTHOR]

Artificial light at night (ALAN) has been recognized as a biodiversity threat due to the drastic effects it can have on many organisms. In wild birds, artificial illumination alters many natural behaviors that are important for fitness, including chick provisioning. Although incubation is a key determinant of the early developmental environment, studies into the effects of ALAN on bird incubation behavior are lacking. We measured nest temperature in nest boxes of great tits during the incubation period in two consecutive years. Nest boxes were located in eight previously dark field sites that have been experimentally illuminated since 2012 with white, green, or red light, or were left dark. We tested if light treatment affected mean nest temperature, number of times birds leave the nest (off-bout frequency), and off-bout duration during the incubation period. Subsequently, we investigated if incubation behavior is related to fitness. We found that birds incubating in the white light during a cold, early spring had lower mean nest temperatures at the end of incubation, both during the day and during the night, compared to birds in the green light. Moreover, birds incubating in white light took fewer off-bouts, but off-bouts were on average longer. The opposite was true for birds breeding in the green light. Low incubation temperatures and few but long off-bouts can have severe consequences for developing embryos. In our study, eggs from birds that took on average few off-bouts needed more incubation days to hatch compared to eggs from birds that took many off-bouts. Nevertheless, we found no clear fitness effects of light treatment or incubation behavior on the number of hatchlings or hatchling weight. Our results add to the growing body of literature that shows that effects of ALAN can be subtle, can differ due to the spectral composition of light, and can be year-dependent. These subtle alterations of natural behaviors might not have severe fitness consequences in the short-term. However, in the long term they could add up, negatively affecting parent condition and survival as well as offspring recruitment, especially in urban environments where more environmental pollutants are present.

AIM: To investigate the effects of spectral composition and light intensity on natural refractive development in guinea pigs. METHODS: A total of 124 pigmented guinea pigs (2-week-old) were randomly assigned to three groups at high (Hi; 4000 lx), medium (Me; 400 lx) and low (Lo; 50 lx) light intensities under a 12:12 light/dark cycle for 6wk. Each group was subdivided into subgroups with the following spectra: broad spectrum Solux halogen light (BS), 600 nm above-filtered continuous spectrum (600F), 530 nm above-filtered continuous spectrum (530F), and 480 nm above-filtered continuous spectrum (480F; HiBS: n=10, Hi600F: n=10, Hi530F: n=10, Hi480F: n=10, MeBS: n=10, Me600F: n=10, Me530F: n=10, Me480F: n=10, LoBS: n=11, Lo600F: n=12, Lo530F: n=10, Lo480F: n=11). Refractive error, corneal curvature radius, and axial dimensions were determined by cycloplegic retinoscopy, photokeratometry, and A-scan ultrasonography before and after 2, 4, and 6wk of treatment. Average changes from both eyes in the ocular parameters and refractive error were compared among different subgroups. RESULTS: After 6wk of exposure, high-intensity lighting enhanced hyperopic shift; medium- and low-intensity lighting enhanced myopic shift (P

Forty-seven patients suffering from neck and/or back pain were examined; their temperament was evaluated using the Eysenck Personality Questionnaire (EPQ); the pain syndromes in these subjects were described according to the visual analogous scale (VAS). All patients were subjected to the detailed EEG examination. As was found, characteristics of pain in subjects of the examined group noticeably depended on the type of their temperament. Simultaneously, spectral powers (SPs) of EEG oscillations of the beta range also demonstrated specific dependences on the temperament type. Spectral powers of beta activity showed negative correlations (in many cases significant) with the extra/introversion estimates of the patients, while correlations with the neuroticism level were positive. The mean pain intensity in patients with choleric and melancholic temperaments showed positive correlations with the intensity of beta activity, while correlations of the periodicity of spinal pain with the above activity were positive and stronger. The above differences are assumed to depend on the functional state of the brain and, primarily, on the degree of activation of the ascending reticular formation reflected on the type of temperament of the individual. The importance of the human neuroconstitution for peculiarities of the pathogenesis of reflex neurological disorders of the spine with neck and back pain is discussed. [ABSTRACT FROM AUTHOR]

Although sunlight is essential for plant growth and development, the relative importance of each spectral region in shaping functional traits is poorly understood, particularly in dynamic light environments such as forest ecosystems.We examined responses of 25 functional traits from groups of 11 shade‐intolerant and 12 understorey shade‐tolerant forb species grown outdoors under five filter treatments differing in spectral transmittance: (a) transmitting c. 95% of solar radiation (280–800 nm); (b) attenuating ultraviolet‐B (UV‐B); (c) attenuating all UV; (d) attenuating all UV and blue light; (e) attenuating all UV, blue and green light.Our results show that UV‐B radiation mainly affected the biochemical traits but blue light mainly affected the physiological traits irrespective of functional strategy, whereas green light affected both sets of traits. This would suggest that differentiation among suites of functional trait responses proceeds according to light quality. Biomass accumulation was significantly increased by UV‐A radiation (contrasting treatment [b] vs. [c]) among shade‐intolerant but decreased by blue light among shade‐tolerant species; green and red light affected whole‐plant morphological development differently according to functional groups. Shade‐tolerant species were more plastic than shade‐intolerant species in response to each spectral region that we examined except for UV‐B radiation.Synthesis. Our results show that differences in the spectral composition of sunlight can drive functional trait expression irrespective of total irradiance received. The different responses of functional traits between functional groups imply that shade‐tolerant and intolerant species have adapted to utilize spectral cues differently in their respective light environments. [ABSTRACT FROM AUTHOR]

Paper and silk are the artworks with the highest light sensitivity. They are very vulnerable to photochemical reactions caused by the radiation of light sources in museum lighting, resulting in irreversible permanent damage such as color fading and discoloration. The basis of lighting protection for these artworks is to clarify the influence of different light sources on paper and silk materials. In this study, 10 kinds of narrow band monochrome light in the visible light range were used as experimental light sources, real cultural relics paper and silk materials were used as experimental samples, and long-term irradiation experiments were carried out under constant temperature and humidity conditions. The color parameters of paper and silk irradiated by different light sources were detected periodically, and the curve of color difference with exposure was drawn. The relative influence coefficients of different spectral bands on the color of paper and silk were obtained by curve analysis. By fitting data regularity and regression analysis, the "relative damage-spectral composition" function was established. The effect of light source on color damage of paper and silk is described by mathematical language, and the influence formula of different spectrum on color damage of paper and silk is obtained. [ABSTRACT FROM AUTHOR]

Artificial lighting has two important effects on sea turtles: It reduces the attractiveness of the beach to nesting females, and thus decreases the number of turtles which place nests in a coastal region, and; it interferes with the hatchlings ability to orient normally from the nest to the ocean.Both of these effects depend upon the overall intensity (energy content) and spectral composition (concentration of heat energy as a function of wavelength) of the light source(s). Habitat alterations associated with FDOT coastal highwayscontribute to many beach lighting problems. The existing Florida Department of Transportation (FDOT) Roadway Lighting Standards do not take into account the biological conditions of adjacent properties when developing roadway lighting systems.This problem was identified in the FDOT 2020 Long Range Transportation Plan which was approved by Secretary of Transportation Ben Watts and the Florida Transportation Commission in March 1995. The 2020 Long Range Plan suggested that FDOT incorporate the findings of the ecosystem management task force into Department procedures, including such ideas as identifying critical sea turtle nesting habitat where alternative street lighting could be installed. In 1998, FDOT entered into a research study with Florida Atlantic University (FAU) that would address the impacts of coastal roadway lighting on adjacent sea turtle nesting beaches. Originally, the purpose of this study was to (i) identify coastal roadway lighting problems, (ii) determine how they can be corrected, and (iii) use this information to develop new and improved lighting standards for roadway design engineers, coastal communities and utility companies. It was expanded to include an embedded roadway lighting demonstration project as well as an evaluation of the safety and roadway user response to embedded roadway lighting that was conducted by the Department of Civil and Coastal Engineering at the University of Florida (UF). These findings were presented at the 2001 ICOET conference in Keystone, Colorado. A recommendation of the UF research study was the need for the development of an Engineering Manual for Designing Roadway Lighting Systems in Environmentally Sensitive Areas. The manual would not necessarily offer new lighting criteria, but would show the designer how to use alternative lighting products in the design of coastal roadway lighting systems. It was determined that this would be a valuable resource for Florida and for the nation (Ellis and Washburn, 2003). The manual would allow the implementation of specialized Coastal Roadway Lighting Standards that would meet the needs of the roadway and satisfy the requirements of the Endangered Species Act.The purpose of this paper is to provide an overview of this latest implementation of FDOT sponsored research to address coastal roadway lighting and its impacts on adjacent sea turtle nesting beaches. This recent project is a work in progress with anticipated completion date of September 2007.

• Light quality and nutrients status are vital environmental trigger for turion formation. • Red light exerts stronger induction effect on turion formation than blue light. • Red/blue light with a ratio of 4 is optimal for turion and starch production. • Optimized light helps to reduce light energy consumption. • Appropriate supplementation of nutrients further promotes turion production. Spectral composition and nutrients status are important environmental factors for biomass production. For realizing the economical and efficient production of duckweed [Spirodela polyrhiza (L.) Schleiden] turion, a promising starch-rich biofuel feedstock, impacts of tailored-lights combined with eutrophic/oligotrophic medium was investigated in this study. Results revealed that nutrients starvation was better for turion production and optimized spectral composition could significantly enhance it. Accompanied with simultaneously enhanced frond biomass and starch content, starch yield of 32.34 g/m2 under fluorescent lamp was largely elevated to 51.71 g/m2 by red/blue: 1/2. Especially, lights with higher ratio of red spectrum exerted strong inductive effect on turion formation under eutrophic condition. Considering the energy consumption, red/blue: 4/1 was the optimal option as it cut down energy cost by 12.56% and owned the highest production efficiency. Moreover, appropriate nutrients supplementation can further improve the starch productivity. Finally, an efficient and economical culture method for turion and starch production was established. [ABSTRACT FROM AUTHOR]

Plants have evolved a suite of photoreceptors to perceive information from the surrounding light conditions. The aim of this study was to examine photomorphogenic effects of light quality on the growth of Scots pine (Pinus sylvestris L.) seedlings representing southern (60 °N) and northern (68 °N) origins in Finland. We measured the growth characteristics and the expression of light-responsive genes from seedlings grown under two LED light spectra: (1) Retarder (blue and red wavelengths in ratio 0.7) inducing compact growth, and (2) Booster (moderate in blue, green and far-red wavelengths, and high intensity of red light) promoting shoot elongation. The results show that root elongation, biomass, and branching were reduced under Retarder spectrum in the seedlings representing both origins, while inhibition in seed germination and shoot elongation was mainly detected in the seedlings of northern origin. The expression of ZTL and HY5 was related to Scots pine growth under both light spectra. Moreover, the expression of PHYN correlated with growth when exposed to Retarder, whereas CRY2 expression was associated with growth under Booster. Our data indicates that blue light and the deficiency of far-red light limit the growth of Scots pine seedlings and that northern populations are more sensitive to blue light than southern populations. Furthermore, the data analyses suggest that ZTL and HY5 broadly participate in the light-mediated growth regulation of Scots pine, whereas PHYN responses to direct sunlight and the role of CRY2 is in shade avoidance. Altogether, our study extends the knowledge of light quality and differential gene expression affecting the early growth of Scots pines representing different latitudinal origins. [ABSTRACT FROM AUTHOR]

Solar radiation is a very important energy source for life on Earth and especially for the proper growth and development of plants. Its spectral composition is necessary for a main physiological process in a plant’s life—photosynthesis. In practical agriculture, plants are cultivated in the stand, which causes neighboring plants not only to compete for water and nutrients but also for light. Living in such an environment, plants have developed different mechanisms for dealing with shading. An aim of the studies conducted here was to determine the effect of the red (R) and far red (FR) range of spectral composition on gas exchange and the other physiological features of spring barley plants. The experiment was conducted in two growth chambers with different spectral compositions of radiation. Spring barley was grown in Mitscherlich pots. The physiological features measured during the two barley developmental phases, i.e., seventh and flag leaves, differed depending on the R/FR ratio used in these chambers. Plants that grew under conditions of a high R/FR ratio showed a higher photosynthesis efficiency, intracellular CO2 concentration, stomatal conductance and transpiration of water but lower values of the water use efficiency (WUE) index. The leaves of plants treated with this kind of light (higher R/FR ratio) had a greater stomata number and higher content of chlorophyll when compared to plants grown under conditions with a low R/FR ratio.

Впровадження в Україні швидкісного руху поїздів з підвищеним їх рухом до 200 км/год вимагає застосування більш потужних, ніж при звичайному русі, видів електрорухомого складу змінного струму, зокрема електровозів. А більш потужні електровози, як відомо, являються і більш потужними генераторами реактивної потужності, транзит якої в системі електричної тяги являється однією із проблем, яку до цього часу не вдалось розв’язати. Тому проектування нових швидкісних ділянок чи перехід існуючих із системи постійного струму на змінний повинні здійснюватись з урахуванням генерування і транзиту в системі електротяги реактивної потужності. Навіть до цього часу в електротехніці існує проблема оцінки реактивної потужності та енергетичних показників нелінійних, тим більше нестаціонарних, споживачів електроенергії. Тому перевагу віддають тій теорії, яка, по-перше, відображає максимум інформації про енергетичний процес і, по-друге, дозволяє оперувати з миттєвими характеристиками системи. В роботі встановлено, що існує певний зв’язок між ВАХ і спектральним складом кіл з несинусоїдними напругою та струмом в колі двополюсника. За результатами досліджень виконано чисельний аналіз зазначеного зв’язку для швидкісного електровоза ДС 3М

Purpose. In the paper it is necessary to: 1) find out the causes of turnouts faults to determine diagnostic features failures; 2) consider the requirements structure, purpose components of turnouts, work and technology of their maintenance to determine the construction of the economic activities related to system to the turnout’s maintenance; 3) substantiate the possibility, necessity and prospects of automated diagnostics turnout’s implementation; 4) elaborate a prototype of an automated hardware and software system for the turnouts control parameters and perform diagnostics on them. Methodology. In the paper possible turnouts faults were presented and manifestations and influence on its work were shown. According to the current technology works the process analyze of turnouts’ maintenance was conducted, were defined the basic performed operations during the examination of appearance, parameters and check the repair or replacement of parts and assemblies. Based on the analysis of reasons of turnouts malfunctioning and their fixes were systematized types of damages and ways to deal with them, an information scheme of troubleshooting were created, opportunities and limits of automating the process of diagnostics were identified and compared with the existing method of turnouts maintenance. A diagnostics system block diagram was created, an algorithm of its work was developed and established main basic principles of operation. Software and hardware to determine the turnout’s state considering diagnostic performance of points in use were applied. Findings. During the experiment was created a method of automated turnout’s diagnostics with AC electric drives, managed centrally. The results of automated hardware and software system make it possible to control turnout’s parameters and perform diagnostics on them. Originality. Authors created the method of turnout’s state determination by current curve and its spectral composition in the circle of turnout electric motor. The de hardware and software centralized point’s diagnostics complex was developed. Practical value. Thanks to the obtained results the operation safety due to a time workers decrease in the area of train’s movement is increased. The human factor in the performance of measurements is eliminated. Hiding and concealment the facts of turnouts malfunction are not possible.

Purpose. Development and implementation the points system diagnostics that would allow determining remotely the current state of turnout with all possible faults, gradual and sudden failures, damages, and in real time to report about their appearance. Methodology. State diagnostics on the values analysis of turnout main parameters is proposed to carry out with the help of a computer and analog-to-digital converter (ADC). Connecting measurements performance is advisable to produce to a shunt ammeter, installed in the working circuit of the point feed panel. ADC converts the analog signal of lost volts at the shunt into digital form and transmits it to a computer which stores the received data on its own recording medium for their further processing and storage. There is special software that is capable to reconnect signal and construct its temporal characteristic as well as decompose it on the spectral components. Using it one can analyze the obtained data, which allows diagnosing state of points upon change the nature, values and composition of the current curve. Findings. The computer diagnosis method was confirmed in practice for possible indications of problems that are associated with both the mechanical part of the turnout and the electrical part of it, while controlling parameters such as the amount of current normal transition, when working on frictions, the duration of the transition, properly adjusted headset and attachment points, the state of the motor. Originality. The use of computer technology in the diagnosis of the state of turnouts during their operation to monitor the current values of technical indicators, analysis and storage for all types of electric switches with different types of engines both DC and AC occurs through digitization and recording signal from measuring shunt of point feeder panel. Practical value. The proposed method enables timely, still in the early stages of defect parts, damages or failures of nodes mechanisms to detect and eliminate them. In addition, it reduces the load on the electrical engineers during schedule maintenance. The introduction of a diagnostic analysis of the turnout using computer technology will allow defining the appearance of faults in the early stages of their formation and preventing development the difficult avoidable damages or necessity for their complete replacement.

Purpose. The paper is aimed to establish the dependence of changes in the time domain and spectral components of the current in the circuit of the AC electric point motor on its technical condition, to identify the common features for the same type of damage. It is necessary using the analysis of the received signals to carry out the remote diagnosis and determination of faults and defects of electric point motors. In addition it suggested to accelerate the process of the failure, malfunction and damage search. Authors propose the automated approach to the service of remote floor automation equipment, which is located in the envelope of trains. Reduction of the threat to life and health of staff by reducing the residence time in the zone of train movement. Reduce the impact of human factors on the result of service. Methodology. The paper studies the structure, parameters and characteristics, the operation and maintenance characteristics of the AC electric point motors. Determination of the main types of possible faults in the process depending on the operating conditions. Presentation of the electric motor as an object of diagnosis. Findings. The time dependences of the current in the circuit of electric point motor for its various states was obtained. The connection between the technical condition of electric point motor and the performance of current curve in time and spectral domains was established. The revealed deviations from the reference signal were justified. According to the obtained results it was made the conclusion. Originality. A method for diagnosing the state of the AC electric point motor by the time dependence and the spectral composition of the current in its circuit was proposed. The connection diagram to the motor windings based on non-infringement of electric parameters of connection circuit in the actual operating conditions was applied. Practical value. The obtained results suggest the possibility and feasibility of further development of the principles of remote diagnosis based on the analysis of temporal and spectral domains of the current curve in the circuit of the AC electric point motor. The implementation and practical application in operation as a separate system for the collection, analysis, processing and data communication is also real and rational. The given system makes possible tracking the changes in key parameters and forming the proposals on impact measures on the existing situation, as well as the ability to predict the state of the objects on the basis of the dependency determination of the previous changes.

Effects of temperament as a constitutional feature of higher nervous activity on the spectral characteristics of ongoing EEG activity were examined in 54 patients with neurological spinal cervical-level disorders (cervicocranialgies, cervicalgies, and cervicobrachialgies). Four types of temperaments were classified in the examined patients, choleric (group ChT, n = 22), sanguine (ST, n = 10), melancholic (MT, n = 19), and phlegmatic (PhT, n = 3). Spectral analysis of EEGs showed that normalized powers of the θ rhythm in some cortical areas of patients of the PhT group were lower than those in patients of groups ChT, MT, and ST (P < 0.05). The most significant intergroup specificity of the EEG patterns was found in the normalized power of the β1 and β2 subrhythms. In patients of the MT and PhT groups, these indices were noticeably greater than those in ST and ChT subjects (P< 0.05 and P< 0.01, respectively). As was found, the power of β oscillations correlated with the temperament-related indices, negatively with the estimates of extra/introversion and positively with the neuroticism level (P < 0.05). Thus, temperament-related specificities are in a certain way reflected in the characteristics of mostly β activity and, therefore, are dependent on the level of activity of the cerebral reticular formation. [ABSTRACT FROM AUTHOR]

Key message: An LED spectrum containing blue light advanced bud burst in branches of Betula pendula, Alnus glutinosa and Quercus robur compared with a spectrum without blue light in a controlled environment.Abstract: During spring, utilising multiple cues allow tree species from temperate and boreal regions to coordinate their bud burst and leaf out, at the right moment to capitalise on favourable conditions for photosynthesis. Whilst the effect of blue light (400-500 nm) has been shown to increase percentage bud burst of axillary shoots of Rosa sp., the effects of blue light on spring-time bud burst of deciduous tree species have not previously been reported. We tested the hypotheses that blue light would advance spring bud burst in tree species, and that late-successional species would respond more than early-successional species, whose bud burst is primarily determined by temperature. The bud development of Alnus glutinosa, Betula pendula, and Quercus robur branches, cut from dormant trees, was monitored under two light treatments of equal photosynthetically active radiation (PAR, 400-700 nm) and temperature, either with or without blue light, under controlled environmental conditions. In the presence of blue light, the mean time required to reach 50% bud burst was reduced by 3.3 days in Betula pendula, 6 days in Alnus glutinosa, and 6.3 days in Quercus robur. This result highlights the potential of the blue region of the solar spectrum to be used as an extra cue that could help plants to regulate their spring phenology, alongside photoperiod and temperature. Understanding how plants combine photoreceptor-mediated cues with other environmental cues such as temperature to control phenology is essential if we are to accurately predict how tree species might respond to climate change. [ABSTRACT FROM AUTHOR]