Yellow Light Research Articles

Numerical modeling of Dy3+-doped aluminosilicate fiber lasers for yellow light emission

Numerical simulations of Dy3+-doped aluminosilicate fiber lasers for yellow light emission are presented. The 4F9/2→6H13/2 laser transition emitting at approximately 580 nm has been developed experimentally with 445 nm diode pumping and shows promise for higher output power in both silicate and in particular fluoride glass hosts. In this report, we focus on accumulating the published spectroscopic data in order to quantify cross relaxation (CR) in each of these hosts and use it to estimate its role in the laser dynamics. The model involves calculation of the branching ratios, and radiative and nonradiative decay rates and compares well with reported experimental results. We show the important role of the background losses on previous laser performance and the relatively strong increase in the laser threshold as a result of CR despite the moderately low Dy3+ concentrations that have been experimentally tested.

Postmortem Protocols of Implantable Neurosurgical Devices: A Cross-Sectional Survey

BackgroundImplantable devices are increasingly more common for management of movement disorders, pain, and epilepsy. These devices are often complex and constructed of non-biodegradable or hazardous materials. Therefore, proper post-mortem handling of these devices is exceedingly important. Unfortunately, there is no consolidated resource available for post-mortem neuromodulation device protocols. Thus, we surveyed and catalogued the protocols for implantable devices to summarize proper post-mortem device protocols for implantable neurosurgical devices currently on the market. MethodsWe performed a cross-sectional study of companies producing commonly implanted neurosurgical devices. Using information from company websites, user manuals, and catalogs we categorized devices into three groups: A (formal recommendation for explantation), B (recommendation for explantation without formal company protocol), and C (explantation is not necessary). We then compiled the data into a stoplight diagram, providing a clear post-mortem disposal algorithm for each device category. ResultsTwelve companies were queried regarding 46 devices. Post-mortem protocols were available for 50% (23/46) of devices; the remaining devices did not have formal recommendations. Overall, 50% of devices were classified as Category A "red light" on the stoplight diagram based on recommendations, 10.9% as Category B "yellow light," and the remaining 39.1% were classified as Category C "green light" indicating they are safe to bury or cremate. ConclusionsEvolution in therapies and growth in functional neurosurgery has expanded the range of implantable neurosurgical devices. We provide an educational document summarizing their post-mortem protocols. This resource aims to aid healthcare providers and encourage proper disposal practices during burial or cremation.

Physicochemical Properties of Oil of Polygala multiflora Poir. Grown in Burkina Faso

Polygala multiflora is an important source of oil that needs to be valorized. This study aimed to investigate the potential of P. multiflora as an oleaginous plant. The physical and chemical properties of oil extracted from P. multiflora seeds were analyzed according to standard methods. The main physical parameters were yield of oil (43.25 ± 2.3%), relative density (0.912 ± 0.031), melting point (2.42±0.6°C), and refraction index (1.45±0.02), yellow light color. Chemical characteristics were: free fatty acids (1.97±0.2 % ac. Oleic), acidity index (6.93±0.14 mg KOH/g), saponification index (186.3±9.31mg KOH/g), iodine index (40.37±0.5 gI2/100g), and peroxide index (1.58±0.05 Meq O2/kg). Overall, P. multiflora seed oil has shown properties in line with standards for food, cosmetic and pharmaceutical use.

Optimizing traffic light signal timing using a yellow interval model: Methodology and empirical evaluation

All over the world, especially in urban areas, the growing population and prosperity of the car industry have resulted in a steady increment in vehicles on the road, leading that already-built car-transportation infrastructure can not be commensurate with the traffic demand. Consequently, this will cause traffic congestion and thus a higher rate of traffic accidence. In such circumstances, the ability of traffic management becomes indispensable and crucial to ameliorate or even solve this problem. Although various advanced approaches can provide effective traffic management, the cost can be prohibitive to execute them pervasively. Many algorithms, especially machine learning related, require a mass of input data and a high hash rate. As a result, massive sensor systems, advanced computers, and elaborate programming will be unavoidable, which are costly. Two models in this paper, respectively, yellow light interval and traffic-light signalization, are based on summarizing and improving on previous models and are easy to understand and apply. The model focuses on timing the traffic light to maximize the number of vehicles passing through a traffic intersection in a given time. Many authors in their paper on traffic-light signalization hardly consider the effect of yellow light intervals. This paper provides a relatively comprehensive model of traffic-light signalization. Although the model in this paper is inferior to those advanced models utilized in effectiveness, this model can be applied simpler than others.

The Behavioral and Productive Characteristics of Japanese Quails (Coturnix japonica) Exposed to Different Monochromatic Lighting

The purpose of this study is to examine the impact of monochromatic illuminations at wavelengths of white (400–700 nm), green (560 nm), yellow (580 nm), blue (480 nm), and red (660 nm) on the performance and behavioral traits of Japanese quails throughout their fattening period. A total of 300 quails in five lighting experimental groups were housed in their conventional rearing cages. Weekly live weights of quails were measured individually, developmental stability was determined, and behavior and fear tests were performed. The body weight averages of quails exposed to blue, green, and yellow light were determined to be greater than those exposed to white and red light (p < 0.05). In terms of the mature weight parameter and the weight of the inflection point of the Gompertz growth model, the averages of the quails exposed to green and blue monochromatic lighting were higher (p < 0.05). The most negative findings on aggressive behavior were observed in birds exposed to monochromatic yellow and red light. Although the body weight of quails exposed to yellow monochromatic lighting was similar to that of quails exposed to green and blue monochromatic lighting, green and blue monochromatic lighting produced the best results in terms of growth, behavior, and developmental stability characteristics. Consequently, it is believed that consistently using green or blue monochromatic lighting programs when raising Japanese quails may provide economic advantages to the producers.

Traditional Herb (Moxa) Modified Zinc Oxide Nanosheets for Quick, Efficient and High Tissue Penetration Therapy of Fungal Infection.

Fungal infection possesses the characteristics of high invasion depth and easy formation of a biofilm under the skin, which greatly hinders the treatment process. Here, traditional Chinese medicine moxa is carbonized and modified with zinc oxide (ZnO) nanosheets to synthesize carbonized moxa@ZnO (CMZ) with the dual response properties of yellow light (YL) and ultrasound (US) for synergistic antifungal therapy. CMZ with narrow bandgap can respond to long-wavelength YL that is highly safe and helpful for skin repair. Simultaneously, CMZ with a piezoelectric effect can further enhance the photocatalytic efficiency under the stimulation of US with high tissue penetration. Gene mechanism investigation indicates that when exposed to US and YL irradiation, CMZ-based therapy can adjust the expression of genes associated with fungal virulence, metabolic activity, mycelial growth and biofilm development, thus efficaciously eradicating planktonic Candida albicans (C. albicans) and mature biofilm. Importantly, despite the 1.00 cm thick tissue barrier, CMZ can rapidly eliminate 99.9% of C. albicans within 4 min, showing a satisfactory deep fungicidal efficacy. The in vivo therapeutic effect of this strategy is demonstrated in both open wound and deep cutaneous infection tests, speaking of dramatically better efficacy than the traditional fungicide ketoconazole (KTZ).

A fluorogenic nitric oxide donor induced by yellow LED light for cells proliferation inhibition and imaging

Nitric oxide (NO), as a vital cellular signalling molecule in physiological processes, has been found to play an important role in various biological functions. In this study, we rationally designed three NO donors by tethering nitrobenzene derivatives to three fluorescent chromophores. NX-NO was found to release NO and exhibit a high fluorescence turn-on signal ratio upon exposure to LED yellow light. Additionally, it had excellent photo-stability and good inhibitory activity against cancer cell proliferation, and was successfully applied to cell imaging. Moreover, we detected the release of NO and fluorescence response in the blood of a mouse, suggesting its potential therapeutic application in living organisms.

YELLOW LIGHT THE NEXT TECHNOLOGY FOR SMART WATCHES

Light emitting diodes (LED) are often found in wearable smart electronic devices, such as smart watches, health care monitoring system etc. These are utilized for photoplethysmography (PPG) to monitor a variety of physical health factors. Wearable health monitoring systems have been developed as an outcome of the growth of sensor-based process to deliver real-time feedback information to promote health. This technique has the potential to help with symptom checking and treatment in sophisticated diseases, such as pain management.

Influence of coloured lights on growth and enzyme production of beneficial endophytic fungi.

The influence of light regulation on fungal growth and enzyme production was tested on endophytic isolates of Fusarium proliferatum (CCH), Colletotrichum boninense (PL1, PL9, OL2), Colletotrichum gloeosporiodes (OL3) and Colletotrichum siamense (PL3). The isolates were treated with blue, red, green, and yellow light, while white fluorescent light (12h light/12h dark photoperiod) and 24h dark conditions were applied as control. Results revealed that coloured light treatments induced formation of circadian rings, while exposure to white light and dark conditions showed less pronounced circadian rings. Growth and sporulation of endophytes were not significantly influenced by light. By contrast, enzyme production was affected by coloured light treatments, notably with red (amylase), blue (cellulase) and yellow (cellulase, xylanase, L-asparaginase) light, resulting in lower enzyme levels for certain isolates. Under control conditions, enzyme production was relatively higher for amylase, cellulase, xylanase (for cultures incubated in the dark), and for L-asparaginase (for cultures incubated in white fluorescent light). Among the endophytic isolates, F. proliferatum (CCH) showed better response to coloured light treatment as higher sporulation and enzyme production was detected, although growth was significantly suppressed. On the contrary, C. gloeosporiodes (OL3) showed better growth but significantly lower enzyme production and sporulation when treated with the various coloured light. This study revealed that coloured light may have the potential to manipulate growth, sporulation and enzyme production in certain fungal species as strategies for fungal control or for harnessing of valuable enzymes.

Modulation of the emission spectrum of rare-earth ions using inverse-designed photonic crystals cavities.

Rare-earth elements play an indispensable role in the optical communication and laser industries, due to their superior luminescent properties. Nevertheless, the selective enhancement and suppression of different emission bands during energy level transitions for multi-band emitting rare-earth ions presents a significant research challenge, which we aim to address. This study explores the potential of leveraging an inverse-designed dual-cavity photonic crystals structure to manipulate the emission spectrum, thereby facilitating the augmentation or suppression of distinct emission bands. We utilized a convolutional neural network model to establish the relationship between geometric parameters and the local density of states, forecasting the optimal cavity geometry parameters for achieving the desired modulation outcomes. This paper delineates the neural network's generalization capabilities, along with the modulation efficacy of the dual-cavity configuration, both confirmed through numerical validation. Our findings highlight the modulatory capacity of Dy3+ ions, which exhibit three emission spectrum in the visible range, to achieve pure color light emission within the devised cavity structure. Notably, our approach yielded enhancements of up to 2.79-fold and 2.81-fold in pure yellow and red light emissions respectively, compared to free space emissions. The single-sided emission enhancement reaches 16.28-fold for yellow light and 30.79-fold for red light. This emphasizes the transformative potential of this methodology in crafting rare-earth-based luminescent materials with meticulously engineered emission attributes.

Behavioral responses of cave-roosting bats to artificial light of different spectra and intensities: Implications for lighting management strategy

Artificial light at night has become an emerging environmental pollutant, posing a serious threat to biodiversity. Cave-roosting animals are vulnerable to light pollution due to long-term adaptation to nocturnal niches, and the problem is especially severe in the context of cave tourism and limestone mining. Mitigating the adverse impacts of artificial light on cave-dwelling animals presents a challenge. This study aimed to assess the relative contributions of spectral parameters and light intensity to the emergence behavior of nine cave-roosting bat species: Rhinolophus macrotis, Rhinolophus pearsonii, Rhinolophus rex, Rhinolophus pusillus, Rhinolophus siamensis, Rhinolophus sinicus, Hipposideros armiger, Myotis davidii, and Miniopterus fuliginosus. We manipulated light spectra and intensities through light-emitting diode (LED) lighting and gel filters at the entrance of bat roost. We monitored nightly passes per species to quantify bat emergence under the dark control and ten lighting conditions (blue, green, yellow, red, and white light at high and low intensities) using ultrasonic recording. Our analyses showed that the number of bat passes tended to be reduced in the presence of white, green, and yellow light, independent of light intensity. In contrast, the number of bat passes showed no pronounced differences under the dark control, blue light, and red light. The number of bat passes was primarily affected by LED light's blue component, red component, peak wavelength, and half-width instead of light intensity. These results demonstrate that spectral parameters of LED light can significantly affect emergence behavior of cave-dwelling bats. Our findings highlight the importance of manipulating light colors to reduce the negative impacts of light pollution on cave-roosting bats as a function of their spectral sensitivity. We recommend the use of gel filters to manage existing artificial lighting systems at the entrance of bat-inhabited caves.

Structural and optical properties of Cd2MgTeO6:Dy3+, Na+ phosphors for potential application in w-LEDs and personal identification

Cd2MgTeO6:Dy3+, Na+ phosphors were synthesized via a high-temperature solid-phase reaction. Phase purity, structure, surface morphology, luminescent properties, and thermostability of the samples were analyzed exactly. Under 351 nm excitation, Cd2MgTeO6:Dy3+, Na+ phosphors possessed three emission peaks: 4F9/2-6HJ/2 (J = 15, 13, 11). The phosphors mainly emitted yellow light due to the intensity of 4F9/2-6H13/2 being higher than other energy level transitions. The optimal doping concentration of Cd2MgTeO6:xDy3+, xNa+ phosphor was x = 10 mol% and the mechanism of concentration quenching was the quadrupole-quadrupole interaction. The phosphors possessed good thermostability and high activation energy (Ea = 0.41 eV). The chromaticity coordinate (CIE) coordinates of Cd2MgTeO6:Dy3+, Na+ were located yellow region and were almost the same at different doping concentration. For Cd2MgTeO6: 10 mol%Dy3+, 10 mol%Na+ phosphor, the internal quantum efficiency (IQE) was 20.55% and the cell viability for the cytotoxicity test was bigger than 88.1%. White-light emitting diode (w-LED) was fabricated with an excellent correlated color temperature (CCT = 5340 K) and a high color rendering index (CRI = 88). Cd2MgTeO6:10 mol%Dy3+, 10 mol%Na+ phosphor could display the feature of latent fingerprint (LFP) and lip print (LP) excellently. Hence, the phosphor could excellently apply to the three-level features of latent fingerprint and six characteristics of lip print identification. In general, Cd2MgTeO6:Dy3+, Na+ phosphors have great potential in w-LEDs and personal identification.

Effects of Light Color on the Growth, Feeding, Digestion, and Antioxidant Enzymes of Tripneustes gratilla (Linnaeus, 1758).

To study the effects of light color on sea urchin (Tripneustes gratilla), blue light (B, λ450nm), yellow light (Y, λ585-590nm), red light (R, λ640nm), green light (G, λ510nm), white light (W, λ400-780nm), and darkness (H) groups were established in a recirculating seawater aquaculture system. Six different LED light color treatment groups with a photoperiod of 12 L:12 D were tested for 30 days to investigate the effects of different light colors on the feeding, growth, and enzyme activities of T. gratilla (142.45 ± 4.36 g). We found that using different LED light colors caused significantly different impacts on the feeding, growth, and enzyme activity of T. gratilla. Notably, the sea urchins in group B exhibited better growth, with a weight gain rate of 39.26%, while those in group R demonstrated poorer growth, with a weight gain rate of only 26%. The feeding status differed significantly (p < 0.05) between groups B and R, with group B consuming the highest daily intake (6.03 ± 1.69 g) and group R consuming the lowest (4.54 ± 1.26 g). Throughout the three phases, there was no significant change in the viability of the α-amylase (p > 0.05). Conversely, the pepsin viability significantly increased (p < 0.05) in group B. The lipase viability consistently remained at the lowest level, with no notable differences between group W and group B. In group R, both the α-amylase and pepsin viabilities remained lower, whereas the lipase viability was noticeably greater in each phase than in group B (p < 0.05). Among the antioxidant enzymes, group R exhibited a trend of initial increase followed by decreases in catalase, superoxide dismutase, and glutathione peroxidase activities, particularly during the third stage (15-30 days), during which a significant decrease in antioxidant enzyme activity was observed (p < 0.05). Taken together, these findings suggest that blue light positively affects the growth, feeding, digestion, and antioxidant capacity of T. gratilla in comparison with those in other light environments, whereas red light had an inhibitory effect. Furthermore, T. gratilla is a benthic organism that lives on shallow sandy sea beds. Thus, as short wavelengths of blue and green light are more widely distributed on the seafloor, and long wavelengths of red light are more severely attenuated on the seafloor, shorter wavelengths of light promote the growth of bait organisms of sea urchins, which provide better habitats for T. gratilla.

Synthesis and characterization of Dy-doped Zn2SiAl2O4 nanophosphor for color modulation in advanced lighting systems

Nanoparticles of Zn2SiAl2O4 infused with Dy3+ were produced through a traditional co-precipitation approach. We investigated the particles' structural attributes and physical characteristics using tools such as X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), UV–Vis absorption spectroscopy, and photoluminescence (PL) spectrometry. The XRD outcomes validated the crystalline nature of the nanoparticles and showed the effective replacement of Dy3+ ions in the place of Zn2+ ions within the matrix and with increasing Dy concentration from 0.5 % to 1.25 %, the crystallite size decreased from 84 nm to 53 nm. The SEM visuals offered clarity on the shape, dimension, and spread of these particles. FTIR analysis further confirmed the composition and structure of the nanoparticles by identifying the chemical bonds and functional groups. UV–visible absorption spectroscopy revealed increase in the optical energy bandgap from 4.45 eV to 4.55 eV with increasing Dy3+ content, indicating potential for optical applications. The photoluminescence spectrometry results featured a prominent transition at approximately 646 nm, suggest that the phosphor has the capability to function as a vivid yellow light emitter and demonstrate their potential for application in optoelectronics, photonics, and luminescent materials.

Cyanorhodopsin-II represents a yellow-absorbing proton-pumping rhodopsin clade within cyanobacteria.

Microbial rhodopsins are prevalent in many cyanobacterial groups as a light-energy-harvesting system in addition to the photosynthetic system. It has been suggested that this dual system allows efficient capture of sunlight energy using complementary ranges of absorption wavelengths. However, the diversity of cyanobacterial rhodopsins, particularly in accumulated metagenomic data, remains underexplored. Here, we used a metagenomic mining approach, which led to the identification of a novel rhodopsin clade unique to cyanobacteria, cyanorhodopsin-II (CyR-II). CyR-IIs function as light-driven outward H+ pumps. CyR-IIs, together with previously identified cyanorhodopsins (CyRs) and cyanobacterial halorhodopsins (CyHRs), constitute cyanobacterial ion-pumping rhodopsins (CyipRs), a phylogenetically distinct family of rhodopsins. The CyR-II clade is further divided into two subclades, YCyR-II and GCyR-II, based on their specific absorption wavelength. YCyR-II absorbed yellow light (λmax = 570nm), whereas GCyR-II absorbed green light (λmax = 550nm). X-ray crystallography and mutational analysis revealed that the difference in absorption wavelengths is attributable to slight changes in the side chain structure near the retinal chromophore. The evolutionary trajectory of cyanobacterial rhodopsins suggests that the function and light-absorbing range of these rhodopsins have been adapted to a wide range of habitats with variable light and environmental conditions. Collectively, these findings shed light on the importance of rhodopsins in the evolution and environmental adaptation of cyanobacteria.

Cool white light generation of Dy3+ activated aluminum sodium calcium borate glass for W-LED application

The Dy3+-activated aluminum sodium calcium borate glass with white light emission might have been created through the melt-quenching process. This research explores the optical and luminescence characteristics of borate glasses. Dy3+-activated glasses exhibit absorption in the visible (VIS) and near-infrared spectrums. The absorption starts from the 6H15/2 ground state to the higher state concerning optical characteristics. The emission spectra of dysprosium-doped glasses' photoluminescence show greater intensity at 483 nm (blue light) and 575 nm (yellow light), which are critical wavelengths for white light-generating materials. The luminescence intensity of Dy3+ ions increased up to a 0.50 mol% concentration, while the decay time decreased with an increasing dysprosium ion concentration. The emission spectra were used to estimate the CIE 1931 chromaticity and corresponding color temperature, revealing a shift towards the cold white light location at that temperature. The stimulated emission cross-section is calculated via the Judd-Ofelt theory. All characteristic outcomes suggest that the existing dysprosium-enabled glasses are excellent materials for generating cool white light in W-LED applications.

RPIOSL: construction of the radiation transfer model for rice leaves

The radiative transfer model of vegetation leaves simulates the transmission mechanism of light inside the vegetation and simulates the reflectivity of blades according to the change law of different components in the process of plant growth. Based on the PIOSL model, this paper combines PIOSL with the structure of rice leaves to construct a radiation transfer model for rice leaves. The parameters of each layer of the RPIOSL model are determined by the Non-dominated Sorting Genetic Algorithm-III. (NSGA-III.) algorithm. The reflectance spectra of 218 rice leaf samples in different periods were simulated using the RPIOSL model. The results show that the mean (RMSE) between the simulated and measured spectra of the constructed RPIOSL model is 0.1074, which is 0.0191 lower than that of the PROSPECT model. Among them, the spectral simulation effect of RPIOSL model in yellow and red light band is the best, and the RMSE at tillering period, jointing period, heading period and grouting period are 0.0584, 0.0576, 0.0724 and 0.0820, respectively. Therefore, the establishment of the RPIOSL model can accurately describe the interaction mechanism between light, which is of great significance for the rapid acquisition of rice growth information and accurate crop management.

Finding the optimal light quality and intensity for the withering process of fuding Dabai tea and its impact on quality formation

This study investigates the pivotal role of withering in shaping the quality of white tea. We used a single-factor experimental design to optimize both the light quality and intensity during the withering process. Using gas chromatography-mass spectrometry (GC-MS), sensory evaluation, and physical and chemical analyses, we identified the ideal parameters as yellow light at an intensity of 5000 lx. Subsequently, we used non-targeted metabolomics and transcriptomics to analyze the mechanism of white tea quality formation at various stages of withering. The results showed significant changes to flavonoids during the withering process, with heightened F3′5′H (flavonoid3,5-hydroxylase) gene expression leading to increased levels of quercetin, myricetin, and luteolin. Conversely, the decreased catechin content was attributed to the decreased expression of most genes in the catechin synthesis pathway. The elevated levels of leucine, isoleucine, and GABA in free amino acids were due to a significant increase in the expression of the genes that synthesize them. Hormone and WGCNA analyses substantiated the importance of ABA, JA, and other key genes in shaping white tea quality during withering. These combined factors orchestrate the gradual formation of the distinctive characteristics of high-quality white tea.

A Workable Solution for Reducing the Large Number of Vehicle and Pedestrian Accidents Occurring on a Yellow Light

A Workable Solution for Reducing the Large Number of Vehicle and Pedestrian Accidents Occurring on a Yellow Light

Factors Influencing Traffic Accidents Involvement: A Case Study of Online Motorcycle Taxi Drivers in Banda Aceh

In Indonesia, online transportation or motorcycle taxi is often used because they can take passengers to their destination at an affordable cost. Still, along with the rise of online motorcycle taxi facilities that are not balanced with safety facilities, human factors significantly influence traffic accidents. This study aims to identify personal characteristics and driver behavior related to anxiety, aggressive driving, impatience, and violations of accident involvement in Banda Aceh city. Data collection in this study was carried out by distributing questionnaires using Google Forms aimed at online transportation drivers, as many as 200 respondents, to determine the characteristics and driving behavior. Structural Equation Modeling (SEM) method with Confirmatory Factor Analysis (CFA) model to analyze the relationship between driving behavior variables on accident involvement in Banda Aceh city. The results of respondents’ perceptions of unsafe driving behavior towards traffic accident involvement show that all indicators have a value above 2.5 on a Likert scale of 1-4. The results of CFA modeling showed that the relationship between variables Anxiety, aggressive driving, and impatience has a positive correlation value with a significant effect on accident involvement. From the modeling, the most significant indicator is the indicator “Taking the opportunity and accelerating the speed of the vehicle when the yellow light before turning red?” with a t-value of 6.996, while the impatience variable is “Feeling impatient or angry at slow drivers and wanting to get ahead of them?” with a t-value of 6.592 and “Feeling worried if you suddenly feel sleepy while driving” with a t-value of 3.598. Based on the results, it can be stated that impatience and aggressive driving lead to accident involvement.