Blue Spectrum Research Articles

Bouncing cosmology in VCDM

We construct an asymmetric bouncing scenario within the VCDM model — also known as type-II minimally modified gravity, — a modified gravity theory with two local physical degrees of freedom. The scenario is exempt of any ghost or gradient instability, ad-hoc matching conditions or anisotropic stress issue (BKL instability). It moreover succeeds in generating the cosmological perturbations compatible with the observations. The scalar spectral index can be adapted by the choice of the equation of state of the matter sector and the form of the VCDM potential leading to an almost scale-invariant power spectrum. Satisfying the CMB bounds on the tensor-to-scalar ratio leads to a blue tensor spectrum.

Effects of LED Red and Blue Spectra Irradiance Levels and Nutrient Solution EC on the Growth, Yield, and Phenolic Content of Lemon Basil (Ocimum citriodurum Vis.)

This research was conducted to study the effects of LED red and blue spectra irradiance levels and nutrient solution (electrical conductivity) and their interaction on the plant growth, yield, and phytochemical contents of lemon basil (Ocimum citriodorum Vis.) in a controlled environment. The controlled environment was equipped with red and blue spectra at a 4:1 ratio with irradiance levels of 80 and 160 µmol m−2 s−1 and irrigated with four different nutrient solution ECs at 1.0, 1.8, 2.6, and 3.4 mS cm−1, cultivated on a vertical structure. The temperature and relative humidity of the controlled environment and the pH of the nutrient solution were maintained at 26 and 18 °C day and night, 65 ± 5%, and pH 6, respectively. It was observed that plant height, canopy diameter, and the number of leaves of lemon basil had significantly increased under the irradiance levels of 160 µmol m−2 s−1 in combination with a nutrient solution EC of 2.6 mS cm−1. In addition, there was an interaction observed between the LED irradiance levels and the nutrient solution EC on the fresh weight of the stem and the dry weight of all the plant parts (leaves, stem, and roots). Lemon basil cultivated at 160 µmol m−2 s−1 and irrigated with 2.6 mS cm−1 was significantly higher in fresh stem weight and dry leaf, stem, and root weight at 17.36, 1.79, 1.82, and 0.22 g, respectively. The ascorbic acid of lemon basil was significantly higher under a treatment of 160 µmol m−2 s−1 irradiance level and an EC of 2.6 mS cm−1, and no interaction was observed. At the same time, there was an interaction observed between the LED irradiance level and the nutrient solution EC on the total phenolic content (TPC), total flavonoid content (TFC), and caftaric acid concentration of lemon basil. Lemon basil cultivated at 160 µmol m−2 s−1 and irrigated with 2.6 mS cm−1 was significantly higher in TPC, TFC, and caftaric acid concentration, with 1440.62 mg gallic acid equivalent to 100 g−1 DW, 1148.79 mg quercetin equivalent to 100 g−1 DW, and 2812.50 mg 100 g−1 DW, respectively. This result indicates that the irradiance levels of red and blue LED spectra at 160 µmol m−2 s−1 and irrigated with a nutrient solution EC of 2.6 mS cm−1 enhances the growth, yield production, and phenolic content of lemon basil in a controlled environment facility.

Spectral optimization of trichromatic white LEDs based on age of lighting user and application scene.

The optimization of trichromatic white light emitting diodes (LEDs) spectrum for application scenes related to the age of lighting users is proposed and demonstrated. Based on the spectral transmissivity of human eyes at different ages, the visual and non-visual responses of human eyes to different wavelengths of light, we have built the blue light hazards (BLH) and circadian action factor (CAF) related to the age of the lighting user. The BLH and CAF are used to evaluate the spectral combinations of high color rendering index (CRI) white LEDs obtained from different radiation flux ratios of red, green, and blue monochrome spectrum. The best spectra of white LEDs for lighting users at different ages in work and leisure scenes are achieved due to the optimization criterion of BLH proposed by us. This research provides a solution for intelligent health lighting design applicable to light users of different ages and application scenes.

High-power supercontinuum lasers with a flat blue spectrum through pump modulation: a numerical study.

We numerically investigate high-power, modulational instability-based supercontinuum sources. Such sources have spectra that reach the infrared material absorption edge and as a result the spectrum has a strong narrow blue peak (dispersive wave group velocity matched to solitons at the infrared loss edge) followed by a significant dip in the neighboring longer-wavelength region. In a wide range of applications one prefers a broader and more flat blue part within a certain minimum and maximum power spectral density. From the perspective of fiber degradation it would be desirable to achieve this at reduced pump peak powers. We show that it is possible to improve the flatness by more than a factor of 3 by modulating the input peak power, although this comes at the expense of slightly higher relative intensity noise. Specifically, we consider a standard 6.6 W, 80 MHz supercontinuum source with a 455 nm blue edge, which uses 7 ps pump pulses. We then modulate its peak power to generate a pump pulse train having two and three different sub-pulses.

Hunting for C-rich long-period variable stars in the Milky Way’s bar-bulge using unsupervised classification ofGaiaBP/RP spectra

ABSTRACTThe separation of oxygen- and carbon-rich asymptotic giant branch sources is crucial for their accurate use as local and cosmological distance and age/metallicity indicators. We investigate the use of unsupervised learning algorithms for classifying the chemistry of long-period variables from Gaia DR3’s BP/RP spectra. Even in the presence of significant interstellar dust, the spectra separate into two groups attributable to O-rich and C-rich sources. Given these classifications, we utilize a supervised approach to separate O-rich and C-rich sources without blue and red photometers (BP/RP) spectra but instead given broadband optical and infrared photometry finding a purity of our C-rich classifications of around 95 per cent. We test and validate the classifications against other advocated colour–colour separations based on photometry. Furthermore, we demonstrate the potential of BP/RP spectra for finding S-type stars or those possibly symbiotic sources with strong emission lines. Although our classification suggests the Galactic bar-bulge is host to very few C-rich long-period variable stars, we do find a small fraction of C-rich stars with periods $\gt 250\, \mathrm{day}$ that are spatially and kinematically consistent with bar-bulge membership. We argue the combination of the observed number, the spatial alignment, the kinematics, and the period distribution disfavour young metal-poor star formation scenarios either in situ or in an accreted host, and instead, these stars are highly likely to be the result of binary evolution and the evolved versions of blue straggler stars already observed in the bar-bulge.

Colour Selection and Olfactory Responses of Papilio demoleus during Foraging and Courtship.

Colours and odours are the most important cues for butterflies to localise food and mating partners. We studied the visual and olfactory responses of the widely distributed butterfly Papilio demoleus Linnaeus during foraging and courtship. P. demoleus visited odourless flowers with six colours except green and black, with red as the favourite colour (650-780 nm). Males and females differed in behaviour while visiting flowers. Males were more active than females during foraging. The application of honey water resulted in a significant increase in flower visits by both females and males, and they scarcely visited the apetalous branches with odours. Under natural conditions, four patterns were observed: males chasing males (42.28%), males chasing females (30.56%), females chasing females (13.73%), and females chasing males (13.43%). Males chasing males was the most frequent, probably because males drive away competing con-specific males. When butterflies visited odourless mimics, males chasing females (70.73%) and males chasing males (29.27%) also occurred, indicating that males could accurately distinguish mates using colours only without any chemical cues, and females need chemical cues. The behavioural responses of P. demoleus to floral visits and courtship suggest that colour is the dominant factor during foraging and courtship. We verified the presence of P. demoleus rhodopsin genes, including Rh2, Rh3, Rh4, and Rh5, for long wavelength, blue, and ultraviolet (UV) spectrum recognition, which is consistent with the colour recognition of flowers and wings during visiting flowers and courtship.

Options for treatment correction in children with atopic dermatitis

Background. Atopic dermatitis (AD) treatment is based on clinical recommendations (CR, 2021). It is reasonable to use other effective treatment methods due to continuous and often relapsing course of dermatosis, and thus physiotherapy treatment is important.Objective. The aim of the study is to evaluate the efficacy of chromotherapy with a spectrum of 470 nm (blue spectrum) in children with AD complicated by secondary infection.Methods. The study included 40 children aged from 2 to 12 years. All patients received standard treatment regimen according to the current CR and were divided into 2 groups, equal in number (20 patients each): the control group (CG — only traditional therapy), and the experimental group (EG — traditional therapy + blue spectrum chromotherapy (470 nm)).Results. The SCORAD index (the sum of objective and subjective features) before treatment in the whole patient cohort was 32.5 ± 6.99 points, which corresponds to the moderate-severe form of the disease. The positive effect of therapy was registered in all patients (n = 40). Persistent process stabilization on the 7th day 7 of treatment in EG was observed in 8 patients, and in CG — in 2 (40% and 10%, respectively); p = 0.065. After the end of the treatment (10th day) persistent remission prevailed in EG and was registered in 90% (n = 18) of patients, and in CG — only in half of all patients, 55% (n = 11); p = 0.031. The evaluation of the AD severity due to the SCORAD index in patients with residual clinical manifestations clearly indicates that in EG its value corresponded to a mild disease course (p < 0.001), and in CG — the lower border of the moderate-severe and the upper border of the mild disease course (p < 0.05).Conclusion. The use of blue spectrum chromotherapy in treatment of children with AD is the effective and accessible method that can be used as an addition to traditional treatment in cases with secondary infectious complications. Its use has a potential to exclude polypragmasy in this dermatosis treatment.

The power of light: Impact on the performance of biocontrol agents under minimal nutrient conditions.

The spectral distribution of light (different wavelength) has recently been identified as an important factor in the dynamics and function of leaf-associated microbes. This study investigated the impact of different wavelength on three commercial biocontrol agents (BCA): Bacillus amyloliquefaciens (BA), Pseudomonas chlororaphis (PC), and Streptomyces griseoviridis (SG). The impact of light exposure on sole carbon source utilization, biofilm formation, and biosurfactant production by the selected BCA was studied using phenotypic microarray (PM) including 190 sole carbon sources (OmniLog®, PM panels 1 and 2). The BCA were exposed to five monochromatic light conditions (420, 460, 530, 630, and 660 nm) and darkness during incubation, at an intensity of 50 μmol m-2 s-1. Light exposure together with specific carbon source increased respiration in all three BCA. Different wavelengths of light influenced sole carbon utilization for the different BCA, with BA and PC showing increased respiration when exposed to wavelengths within the blue spectrum (420 and 460 nm) while respiration of selected carbon sources by SG increased in the presence of red light (630 and 660 nm). Only one carbon source (capric acid) generated biosurfactant production in all three BCA. A combination of specific wavelength of light and sole carbon source increased biofilm formation in all three BCA. BA showed significantly higher biofilm formation when exposed to blue (460 nm) and green (530 nm) light and propagated in D-sucrose, D-fructose, and dulcitol. PC showed higher biofilm formation when exposed to blue light. Biofilm formation by SG increased when exposed to red light (630 nm) and propagated in citraconic acid. To increase attachment and success in BCA introduced into the phyllosphere, a suitable combination of light quality and nutrient conditions could be used.

Two genes, ANS and UFGT2, from Vaccinium spp. are key steps for modulating anthocyanin production.

Anthocyanins are a major group of red to blue spectrum plant pigments with many consumer health benefits. Anthocyanins are derived from the flavonoid pathway and diversified by glycosylation and methylation, involving the concerted action of specific enzymes. Blueberry and bilberry (Vaccinium spp.) are regarded as 'superfruits' owing to their high content of flavonoids, especially anthocyanins. While ripening-related anthocyanin production in bilberry (V. myrtillus) and blueberry (V. corymbosum) is regulated by the transcriptional activator MYBA1, the role of specific structural genes in determining the concentration and composition of anthocyanins has not been functionally elucidated. We isolated three candidate genes, CHALCONE SYNTHASE (VmCHS1), ANTHOCYANIDIN SYNTHASE (VmANS) and UDP-GLUCOSE : FLAVONOID-3-O-GLYCOSYLTRANSFERASE (VcUFGT2), from Vaccinium, which were predominantly expressed in pigmented fruit skin tissue and showed high homology between bilberry and blueberry. Agrobacterium-mediated transient expression of Nicotiana benthamiana showed that overexpression of VcMYBA1 in combination with VmANS significantly increased anthocyanin concentration (3-fold). Overexpression of VmCHS1 showed no effect above that induced by VcMYBA1, while VcUFGT2 modulated anthocyanin composition to produce delphinidin-3-galactosylrhamnoside, not naturally produced in tobacco. In strawberry (Fragaria × ananassa), combined transient overexpression of VcUFGT2 with a FLAVONOID 3´,5´-HYDROXYLASE from kiwifruit (Actinidia melanandra) modulated the anthocyanin profile to include galactosides and arabinosides of delphinidin and cyanidin, major anthocyanins in blueberry and bilberry. These findings provide insight into the role of the final steps of biosynthesis in modulating anthocyanin production in Vaccinium and may contribute to the targeted breeding of new cultivars with improved nutritional properties.

A grounded perspective on new early dark energy using ACT, SPT, and BICEP/Keck

We examine further the ability of the New Early Dark Energy model (NEDE) to resolve the current tension between the Cosmic Microwave Background (CMB) and local measurements of H 0 and the consequences for inflation. We perform new Bayesian analyses, including the current datasets from the ground-based CMB telescopes Atacama Cosmology Telescope (ACT), the South Pole Telescope (SPT), and the BICEP/Keck telescopes, employing an updated likelihood for the local measurements coming from the SH 0ES collaboration. Using the SH 0ES prior on H 0, the combined analysis with Baryonic Acoustic Oscillations (BAO), Pantheon, Planck and ACT improves the best-fit by Δχ 2 = -15.9 with respect to ΛCDM, favors a non-zero fractional contribution of NEDE, fNEDE > 0, by 4.8σ, and gives a best-fit value for the Hubble constant of H 0 = 72.09 km/s/Mpc (mean 71.49 ± 0.82 with 68% C.L.). A similar analysis using SPT instead of ACT yields consistent results with a Δχ 2 = -23.1 over ΛCDM, a preference for non-zero f NEDE of 4.7σ and a best-fit value of H0 = 71.77 km/s/Mpc (mean 71.43 ± 0.85 with 68% C.L.). We also provide the constraints on the inflation parameters r and ns coming from NEDE, including the BICEP/Keck 2018 data, and show that the allowed upper value on the tensor-scalar ratio is consistent with the ΛCDM bound, but, as also originally found, with a more blue scalar spectrum implying that the simplest curvaton model is now favored over the Starobinsky inflation model.

Design and construction of a microfluidics workstation for high-throughput multi-wavelength fluorescence and transmittance activated droplet analysis and sorting.

Droplet microfluidics has revolutionized quantitative high-throughput bioassays and screening, especially in the field of single-cell analysis where applications include cell characterization, antibody discovery and directed evolution. However, droplet microfluidic platforms capable of phenotypic, fluorescence-based readouts and sorting are still mostly found in specialized labs, because their setup is complex. Complementary to conventional FACS, microfluidic droplet sorters allow the screening of cell libraries for secreted factors, or even for the effects of secreted or surface-displayed factors on a second cell type. Furthermore, they also enable PCR-activated droplet sorting for the isolation of genetic material harboring specific markers. In this protocol, we provide a detailed step-by-step guide for the construction of a high-throughput droplet analyzer and sorter, which can be accomplished in ~45 working hours by nonspecialists. The resulting instrument is equipped with three lasers to excite the fluorophores in droplets and photosensors that acquire fluorescence signals in the blue (425-465 nm), green (505-545 nm) and red (580-630 nm) spectrum. This instrument also allows transmittance-activated droplet sorting by analyzing the brightfield light intensity transmitting through the droplets. The setup is validated by sorting droplets containing fluorescent beads at 200 Hz with 99.4% accuracy. We show results from an experiment where droplets hosting single cells were sorted on the basis of increased matrix metalloprotease activity as an application of our workstation in single-cell molecular biology, e.g., to analyze molecular determinants of cancer metastasis.

Transcriptome Dataset of Strawberry (Fragaria × ananassa Duch.) Leaves Using Oxford Nanopore Sequencing under LED Irradiation and Application of Methyl Jasmonate and Methyl Salicylate Hormones Treatment

This data descriptor introduces a transcriptome dataset of strawberry plant left exposed to an LED light treatment and plant hormones of Methyl Jasmonate (MeJA) and Methyl Salicylate (MeSA). These data consist of a transcriptome dataset (four libraries) obtained from the leaves of strawberry plants treated with LEDs of blue and red spectrums and the hormones of Methyl Jasmonate (MeJA) and Methyl Salicylate (MeSA), which allowed us to conduct a further analysis of the growth and development processes of strawberry plants. In addition, we describe detailed procedures on how the plants were prepared and treated and how the data were generated and processed beforehand. Further analysis of these data will significantly help to improve our understanding of the molecular mechanisms of LED light and MeJA-MeSA in strawberry plants.

Blue monsters. Why are JWST super-early, massive galaxies so blue?

ABSTRACT The recent James Webb Space Telescope tentative discovery of a population of super-early (redshift z > 10), relatively massive (stellar mass M* = 108–109M⊙) and evolved (metallicity Z ≈ 0.1 Z⊙) galaxies, which nevertheless show blue (β ≃ −2.6) spectra, and very small dust attenuation (AV ≲ 0.02), challenges our interpretation of these systems. To solve the puzzle, we propose two solutions in which dust is either (a) ejected by radiation pressure, or (b) segregated with respect to UV-emitting regions. We clarify the conditions for which the two scenarios apply, and show that they can be discriminated by ALMA observations, such as the recent non-detection of the 88μm dust continuum in GHZ2 (z ≃ 12) favouring dust ejection.

Morphofunctional characteristics of proliferation and apoptosis of germinal epithelium: pathogenesis of temporary azoospermia after local electron irradiation.

At present, the violation of male reproductive function caused by electron irradiation, leading to a decrease in the proliferative activity of germ cells, as well as the development of methods for its correction are relevant. The effect of leukocyte-poor platelet-rich plasma (LP-PRP) growth factors, which have a high regenerative capacity for the restoration of spermatogenesis, remains poorly understood. Objective of the study: immunohistochemical (IHC) assessment of the proliferation of germinal epithelium after electron irradiation with a dose of 2 Gy. Wistar rats (n=60) were divided into groups (conventional names): (I) control (n=30), which were injected with saline; (II) single local irradiation of the testes with electrons at a dose of 2 Gy (n=30). Animals were gradually withdrawn from the experiment over 11 weeks: 5 animals one week after irradiation, and then 5 animals once every 2 weeks. The testes were studied by histological and IHC methods using antibodies to Ki-67, Bcl-2, and p53. Terminal deoxynucleotidyl transferase (TdT) dUTP Nick-End Labeling (TUNEL) method was used to study DNA fragmentation in germ cells, which were stained with TdT solution (Thermo Fisher, USA) and incubated for 60 minutes. The nuclei were counterstained with 4',6-diamidino-2-phenylindole (DAPI) (blue spectrum) (Thermo Fisher), and the luminescence intensity was controlled in a fluorescent microscope with a set of fluorescein isothiocyanate (FITC) filters (green spectrum). IHC analysis of testes after irradiation showed a shift in the proliferative-apoptotic balance towards apoptosis of germ cells: a decrease in the expression levels of Ki-67 (16.3%±1.1%, P<0.05) and Bcl-2 (9.1%±1.1%, P<0.05), an increase in p53-positive cells (74.8%±1.2%, P<0.05) by the end of the experiment. In the experimental model, local irradiation of the testes with electrons at a dose of 2 Gy causes the development of focal hypospermatogenesis, affecting up to 1/8 of the sections of the tubules (in the first week) with a subsequent increase to 1/4 (in the second month), with a tendency to recovery in the third month (temporary azoospermia). The basis of focal hypospermatogenesis is the irradiation-induced proliferative-apoptotic imbalance towards the dominance of apoptosis, which is most pronounced in the pool of spermatogonia.

Medical rehabilitation of children with obstructive uropathy

To develop technologies of physiotherapy application (sound stimulation, selective chromotherapy) for inclusion in comprehensive medical rehabilitation of children with megaloureter. Clinical observations and special examinations have been performed in 90 children with megaloureter aged from 1 to 10 years. The patients were divided into 2 groups: 30 children (study group) received sound stimulation combined with selective chromotherapy; 30 children (the 1st comparison group) - sound stimulation; 30 children (the 2nd comparison group) - selective chromotherapy (blue spectrum). General clinical methods, ultrasound of kidneys and bladder with Doppler monitoring of intrarenal blood flow, functional methods of bladder examination were used. The positive effects of separate and combined application of sound stimulation and selective chromotherapy on clinical and laboratory indicators, urodynamics of urinary tract and renal blood flow in children with megaloureter after surgery have been revealed. The efficacy of selective chromotherapy use in children with megaloureter and comorbid neurologic bladder dysfunction has been proven. Modern technologies for the application of physiotherapy, namely selective chromotherapy and sound stimulation, to include them in the comprehensive medical rehabilitation of children with megaloureter, have been developed for the first time and their high efficacy has been proven.

Coumarin-based acid dye for fluorescent staining of calcium carbonate particles

Vital fluorescence staining of calcium-containing structures in calcifying organisms is a powerful tool for the study of biocalcification. The main dyes used in this field have green or red fluorescence, which may be overlapped with the fluorescence of chlorophyll and other organic substances. We synthesized a novel coumarin-based fluorescent dye QA2 that stains calcium carbonate and calcium phosphate. The fluorescence of this dye depends from environment, it is enhanced in non-polar medium with a shift of the emission maximum to the blue spectrum region. Small vaterite and calcium phosphate particles adsorb QA2 on the surface and exhibit predominantly green fluorescence, while low surface area calcite crystals are stained in bulk and show additional intense blue fluorescence. The ability of the QA2 dye to generate blue fluorescence of calcium carbonate may be useful for tracking calcium carbonate formation at living organisms in the presence of green and red fluorescent organic substances.

TISSUE EXPRESSION OF NEURONAL PROTEINS DURING SCIATIC NERVE REGENERATION AND INFLUENCE OF DIFFERENT SPECTRUM LASER RADIATION

Aim: To determine the effect of laser irradiation of different spectrum on the expression of neuronal proteins (GFAP, S100, NSE and NF-L) in the sciatic nerve during its regeneration after crossing and surgical suturing. Materials and methods: The experiment was performed on 60 laboratory rats of the Wistar line (200-250 g) with crossing of the left sciatic nerve and sutur¬ing with an epineural suture end to end 30 minutes after neurotomy. 90 days later, an immunohistochemical study was performed using specific antibodies (Thermo Fisher Scientific; USA). Results: A study of the marker of non-myelin Schwann GFAP cells showed their pronounced activation with germination in nerve thickness and the formation of weaves of processes around regenerated nerve fibers. The number of S-100-positive myelin Schwann cells decreased, the heterogeneity of their color and the loss of processes were determined. It showed a general decrease in the intensity of NSE- and NF-L-positive staining of nerve fibers regenerated after neurotomy, which was less pronounced when irradiated with a laser with a wavelength of 450-480 nm and 520 nm. Conclusions: In general, the use of laser radiation had a positive effect on the repair of nerve fibers after neurotomy. According to the immunohistochemical study of neuromarkers, the effect of laser irradiation of the blue spectrum was the most effective.

Использование светодиодов синего цвета на промысле гидробионтов в целях повышения эффективности промысла

The article highlights the development of the complex research on using blue spectrum LEDs, taking into account the literature data and the authors' own research. Reaction to light is shown related to stimulating the food activity of aquatic organisms. This is a complex of factors that determine the behavior of aquatic organisms moving towards a light source. Light in the blue segment of spectrum travels the longest distances from the source, so animals and plants have evolved to respond more to the light in this segment. Therefore, using blue LEDs stimu-lates the entire trophic food chain: phytoplankton (phytoplankton growth due to the effective absorption of light energy by chlorophylls a, b and carotenoids in this spectrum) → zooplankton (attracted to the blue light segment due to the reflex about the food presence) → hydrobionts eating zooplankton (attracted to the blue light segment because of the food reflex) → predatory aquatic organisms (also attracted to the blue light segment due to the food reflex). There has been proposed a method of choosing the LED wavelength to optimize the light source subject to the spectral sensitivity of photoreceptors, increasing the LED life with a decreased current, which helps improve the autonomous source life. Based on the nature-like approach and the choice of the light spectrum, using blue LEDs is found reasonable for fishing traditional light-fishing commercial species (saury and squid), as well as other hydrobionts that haven’t been caught using light before (crab, flounder and smelt). This approach allows to use light for catching other aquatic organisms not previously harvested by using light, as well as optimize light sources in fishing traditional commercial species (kilka).

Influence of Mineral Treatment, Plant Growth Regulators and Artificial Light on the Growth of Jewel Sweet Potato (Ipomoea batatas Lam. cv. Jewel) In Vitro

Sweet potato (Ipomoea batatas (L.) Lam), a member of the bindweed family (Convolvulaceae Juss.), is well known for its food, medicinal, and industrial values. It is estimated that more than 7000 sweet potato cultivars have been bred to date. Jewel sweet potato (I. batatas Lam cv. Jewel) is one of the most popular cultivars of sweet potato grown today because of its high nutritional value, delicious taste, and is suitable for all processing methods. However, little is known about the micropropagation of jewel sweet potato. The purpose of this paper was to study the effect of three important factors, including culture medium, plant growth regulators (PGRs), and artificial light sources, on the induction, proliferation, and growth of in vitro I. batatas 'Jewel' shoots obtained from the axillary bud and shoot tip explants. The different Murashige and Skoog (MS) salt levels (33%, 50%, 100%, and 150%) were used to study the influence of mineral treatment. To assess the influence of PGRs, we used 0.5 mg/L indole-3-acetic acid (IAA) combined with various cytokinins, including 0.5-2.0 mg/L 6-benzylaminopurine (BAP), 0.5-2.0 mg/L kinetin (Kn), and 0.1-1.0 mg/L thidiazuron (TDZ). On the other hand, the in vitro shoots were cultivated in a light room with different lighting conditions. Three lighting treatments (differences in the ratio between the red (R) and blue (B) spectra) were used. Research results have shown that the medium containing 50% MS salt concentration supplemented with 0.5 mg/L BAP or 0.5 mg/L Kn combined with 0.5 mg/L IAA was the most suitable for induction, proliferation, and growth of in vitro jewel sweet potato shoots. On the other hand, stem pieces bearing the axillary buds' explants were determined to be suitable for the shoot induction. Using artificial light with different blue/red ratios also had a significant effect on the growth of explants and stimulates shoot or root formation.

Amount of Melanin Granules in Human Hair Defines the Absorption and Conversion to Heat of Light Energy in the Visible Spectrum.

One of the known important functions of hair is protection from extensive sunlight. This protection is accomplished in large part due to natural hair pigmentation which is known to reflect the number of melanin granules (melanosomes) in the hair shaft, and melanin variants. Melanin takes in excessive light energy and converts it to heat in a process called absorption; heat is then dissipated into the environment as infrared radiation, thereby protecting the underlying skin. We used transmission electron microscopy (TEM) to visualize the melanosome counts in samples of human hair, and used thermal microscopy to measure the temperature changes of the samples when exposed to green and blue light lasers. In our experiments green light conversion to heat was highly correlated to the number of melanosomes, whereas blue light conversion to heat was less correlated, which may be because the reddish melanosomes it contains are less effective in absorbing energy from the blue spectrum of light. Anyway, we have shown the metals accumulation in the melanin can be easily visualized with TEM. We confirmed that the amount of melanin granules in human hair defines the conversion to heat of light energy in the visible spectrum.