Light Supplementation in Pitaya Orchards Induces Pitaya Flowering in Winter by Promoting Phytohormone Biosynthesis.

The interaction between light and phytohormones is crucial for plant growth and development. The practice of supplementing light at night during winter to promote pitaya flowering and thereby enhance yield has been shown to be crucial and widely used. However, it remains unclear how supplemental winter light regulates phytohormone levels to promote flowering in pitaya. In this study, through analyzing the transcriptome data of pitaya at four different stages (NL, L0, L1, L2), we observed that differentially expressed genes (DEGs) were mainly enriched in the phytohormone biosynthesis pathway. We further analyzed the data and found that cytokinin (CK) content first increased at the L0 stage and then decreased at the L1 and L2 stages after supplemental light treatment compared to the control (NL). Gibberellin (GA), auxin (IAA), salicylic acid (SA), and jasmonic acid (JA) content increased during the formation of flower buds (L1, L2 stages). In addition, the levels of GA, ethylene (ETH), IAA, and abscisic acid (ABA) increased in flower buds after one week of development (L2f). Our results suggest that winter nighttime supplemental light can interact with endogenous hormone signaling in pitaya, particularly CK, to regulate flower bud formation. These results contribute to a better understanding of the mechanism of phytohormone interactions during the induction of flowering in pitaya under supplemental light in winter.

Harnessing Green Electricity from Food: A Split Black Gram-Based Triboelectric Nanogenerator for a Self-Powered Autonomous Lighting System and Portable Electronics.

Triboelectric nanogenerators (TENGs) represent a promising solution to mounting environmental concerns associated with battery disposal amid the escalating demand for portable electronics. However, prevailing TENG fabrication predominantly relies on nonbiodegradable, nonbiocompatible, and synthetic materials, posing a grave ecological threat. To mitigate this, there is a pressing need to develop eco-friendly and green TENGs leveraging sustainable, naturally occurring materials. This study pioneers the use of split black gram (SBG) as a tribo-positive material for TENGs. SBG's effectiveness as a tribo-positive material stems from its abundance of oxygen-containing functional groups, as confirmed by FTIR analysis, facilitating electron donation during the triboelectric process. SBG offers compelling advantages, including widespread availability, cost-effectiveness, biodegradability, and hydrophobic and adhesive properties due to its richness in starch and protein, positioning it as an optimal choice for eco-conscious TENG manufacturing. The fabrication process of an SBG-TENG is not only economical and facile but also solvent-free, requiring no specialized tools. Demonstrating commendable performance, the SBG-TENG achieves a maximum power density of 15.36 µW/cm2 at 1 MΩ, with an open circuit voltage of 84 V and short circuit current of 28 µA, comparable to recent studies. In practical applications, the SBG-TENG seamlessly integrates with LEDs and portable electronic devices via a full bridge rectifier, successfully powering them postcapacitor charging. Moreover, an autonomous lighting system is developed by embedding the SBG-TENG in a foot mat, enabling wireless light control through human stepping on the mat, introducing power-saving functionality for residential and office environments. In essence, the introduction of the SBG-TENG not only delivers cost-effectiveness but also minimizes the environmental impact by harnessing sustainable energy from food sources.

Advanced Detection of Failed LEDs in a Short Circuit for Automotive Lighting Applications.

This paper addresses the issue of LED short-circuit fault detection in signaling and lighting systems in the automotive industry. The conventional diagnostic method commonly implemented in newer vehicles relies on measuring the voltage drop across different LED branches and comparing it with threshold values indicating faults caused by open circuits or LED short circuits. With this algorithm, detecting cases of a few LEDs short-circuited within a branch, particularly a single malfunctioning LED, is particularly challenging. In this work, two easily implementable algorithms are proposed to address this issue within the vehicle's control unit. One is based on a mathematical prediction model, while the other utilizes a neural network. The results obtained offer a 100% LED short-circuit fault detection rate in the majority of analyzed cases, representing a significant improvement over the conventional method, even in scenarios involving a single malfunctioning LED within a branch. Additionally, the neural network-based model can accurately predict the number of failed LEDs.

Artificial night light and thyroid cancer.

BACKGROUND: The occurrence of thyroid cancer (TC) has increased in recent decades. Exposure to outdoor artificial light at night (ALN) is associated with an increased risk of cancer. AIM: To investigated the impact of ALN, as a significant environmental pollutant, on TC incidence worldwide. METHODS: The assessment involved analyzing satellite ALN data in conjunction with TC incidence data [adjusted standardized rate (ASR)], while considering the quality of cancer registries (QCR), gross domestic product (GDP) per person, and health expenditure per person (HEP) for each country. RESULTS: Results indicated a correlation between higher ASR and ALN exposure percentages, particularly in countries with higher GDP or HEP quartiles (all P< 0.05). Significant differences in ASR were observed across QCR levels, both high and low quality (all P < 0.05), but not in countries without registry activity. However, when evaluating ASR against ALN exposure percentages while considering GDP/HEP quartiles or QCR levels, no significant associations were found (all P > 0.10). CONCLUSION: The findings suggest a potential link between higher GDP and adverse health conditions, serving as possible risk factors for TC, rather than a direct association with ALN. Limitations include the use of cross-sectional data, temporal misalignment, and reliance on ALN as a socioeconomic proxy. It is proposed that light pollution might be connected to a lifestyle conducive to carcinogenesis. Additionally, the presence of higher GDP/HEP could enhance access to diagnostic resources, potentially facilitating TC diagnosis and inclusion in cancer registries.

Simple Sol-Gel Protein Stabilization toward Rainbow and White Lighting Devices.

Fluorescent proteins (FPs) are heralded as a paradigm of sustainable materials for photonics/optoelectronics. However, their stabilization under non-physiological environments and/or harsh operation conditions is the major challenge. Among the FP-stabilization methods, classical sol-gel is the most effective, but less versatile, as most of the proteins/enzymes are easily degraded due to the need of multi-step processes, surfactants, and mixed water/organic solvents in extreme pH. Herein, sol-gel chemistry with archetypal FPs (mGreenLantern; mCherry) is revisited, simplifying the method by one-pot, surfactant-free, and aqueous media (phosphate buffer saline pH = 7.4). The synthesis mechanism involves the direct reaction of the carboxylic groups at the FP surface with the silica precursor, generating a positively charged FP intermediate that acts as a seed for the formation of size-controlled mesoporous FP@SiO2 nanoparticles. Green-/red-emissive (single-FP component) and dual-emissive (multi-FPs component; kinetic studies not required) FP@SiO2 are prepared without affecting the FP photoluminescence and stabilities (>6 months) under dry storage and organic solvent suspensions. Finally, FP@SiO2 color filters are applied to rainbow and white bio-hybrid light-emitting diodes featuring up to 15-fold enhanced stabilities without reducing luminous efficacy compared to references with native FPs. Overall, an easy, versatile, and effective FP-stabilization method is demonstrated in FP@SiO2 toward sustainable protein lighting.

Double Perovskite Single Crystals with High Laser Irradiation Stability for Solid-State Laser Lighting and Anti-counterfeiting.

Laser lighting devices, comprising an ultraviolet (UV) laser chip and a phosphor material, have emerged as a highly efficient approach for generating high-brightness light sources. However, the high power density of laser excitation may exacerbate thermal quenching in conventional polycrystalline or amorphous phosphors, leading to luminous saturation and the eventual failure of the device. Here, for the first time, we raise a single-crystal (SCs) material for laser lighting considering the absence of grain boundaries that scatter electrons and phonons, achieving high thermal conductivity (0.81 W m-1 K-1) and heat-resistance (575 °C). The SCs products exhibit a high photoluminescence quantum yield (89%) as well as excellent stability toward high-power lasers (>12.41 kW/cm2), superior to all previously reported amorphous or polycrystalline matrices. Finally, the laser lighting device was fabricated by assembling the SC with a UV laser chip (50 mW), and the device can maintain its performance even after continuous operation for 4 h. Double perovskite single crystals doped with Yb3+/Er3+ demonstrated multimodal luminescence with the irradiation of 355 and 980 nm lasers, respectively. This characteristic holds significant promise for applications in spectrally tunable laser lighting and multimodal anticounterfeiting.

Regulating Surface-Passivator Binding Priority for Efficient Perovskite Light-Emitting Diodes.

Suppressing trap-assisted nonradiative losses through passivators is a prerequisite for efficient perovskite light-emitting diodes (PeLEDs). However, the complex bonding between passivators and perovskites severely suppresses the passivation process, which still lacks comprehensive understanding. Herein, the number, category, and degree of bonds between different functional groups and the perovskite are quantitatively assessed to study the passivation dynamics. Functional groups with high electrostatic potential and large steric hindrance prioritize strong bonding with organic cations and halides on the perfect surface, leading to suppressed coordination with bulky defects. By modulating the binding priorities and coordination capacity, hindrance from the intense interaction with perfect perovskite is significantly reduced, leading to a more direct passivation process. Consequently, the near-infrared PeLED without external light out-coupling demonstrates a record external quantum efficiency of 24.3% at a current density of 42 mA cm-2. In addition, the device exhibits a record-level-cycle ON/OFF switching of 20 000 and ultralong half-lifetime of 1126.3 h under 5 mA cm-2. An in-depth understanding of the passivators can offer new insights into the development of high-performance PeLEDs.

Multimodal In-Vehicle Hypoglycemia Warning for Drivers With Type 1 Diabetes: Design and Evaluation in Simulated and Real-World Driving.

BACKGROUND: Hypoglycemia threatens cognitive function and driving safety. Previous research investigated in-vehicle voice assistants as hypoglycemia warnings. However, they could startle drivers. To address this, we combine voice warnings with ambient LEDs. OBJECTIVE: The study assesses the effect of in-vehicle multimodal warning on emotional reaction and technology acceptance among drivers with type 1 diabetes. METHODS: Two studies were conducted, one in simulated driving and the other in real-world driving. A quasi-experimental design included 2 independent variables (blood glucose phase and warning modality) and 1 main dependent variable (emotional reaction). Blood glucose was manipulated via intravenous catheters, and warning modality was manipulated by combining a tablet voice warning app and LEDs. Emotional reaction was measured physiologically via skin conductance response and subjectively with the Affective Slider and tested with a mixed-effect linear model. Secondary outcomes included self-reported technology acceptance. Participants were recruited from Bern University Hospital, Switzerland. RESULTS: The simulated and real-world driving studies involved 9 and 10 participants with type 1 diabetes, respectively. Both studies showed significant results in self-reported emotional reactions (P<.001). In simulated driving, neither warning modality nor blood glucose phase significantly affected self-reported arousal, but in real-world driving, both did (F2,68=4.3; P<.05 and F2,76=4.1; P=.03). Warning modality affected self-reported valence in simulated driving (F2,68=3.9; P<.05), while blood glucose phase affected it in real-world driving (F2,76=9.3; P<.001). Skin conductance response did not yield significant results neither in the simulated driving study (modality: F2,68=2.46; P=.09, blood glucose phase: F2,68=0.3; P=.74), nor in the real-world driving study (modality: F2,76=0.8; P=.47, blood glucose phase: F2,76=0.7; P=.5). In both simulated and real-world driving studies, the voice+LED warning modality was the most effective (simulated: mean 3.38, SD 1.06 and real-world: mean 3.5, SD 0.71) and urgent (simulated: mean 3.12, SD 0.64 and real-world: mean 3.6, SD 0.52). Annoyance varied across settings. The standard warning modality was the least effective (simulated: mean 2.25, SD 1.16 and real-world: mean 3.3, SD 1.06) and urgent (simulated: mean 1.88, SD 1.55 and real-world: mean 2.6, SD 1.26) and the most annoying (simulated: mean 2.25, SD 1.16 and real-world: mean 1.7, SD 0.95). In terms of preference, the voice warning modality outperformed the standard warning modality. In simulated driving, the voice+LED warning modality (mean rank 1.5, SD rank 0.82) was preferred over the voice (mean rank 2.2, SD rank 0.6) and standard (mean rank 2.4, SD rank 0.81) warning modalities, while in real-world driving, the voice+LED and voice warning modalities were equally preferred (mean rank 1.8, SD rank 0.79) to the standard warning modality (mean rank 2.4, SD rank 0.84). CONCLUSIONS: Despite the mixed results, this paper highlights the potential of implementing voice assistant-based health warnings in cars and advocates for multimodal alerts to enhance hypoglycemia management while driving. TRIAL REGISTRATION: ClinicalTrials.gov NCT05183191; https://classic.clinicaltrials.gov/ct2/show/NCT05183191, ClinicalTrials.gov NCT05308095; https://classic.clinicaltrials.gov/ct2/show/NCT05308095.

Tunable Narrow-Band Cyan-Emission of Eu2+-doped Nitridomagnesophosphates Ba3-xSrx[Mg2P10N20] : Eu2+ (x=0-3).

Tetrahedron-based nitrides offer a wide range of properties and applications. Highly condensed nitridophosphates are examples of nitrides that exhibit fascinating luminescence properties when doped with Eu2+, making them appealing for industrial applications. Here, we present the first nitridomagnesophosphate solid solution series Ba3-xSrx[Mg2P10N20] : Eu2+ (x=0-3), synthesized by a high-pressure high-temperature approach using the multianvil technique (3 GPa, 1400 °C). Starting from the binary nitrides P3N5 and Mg3N2 and the respective alkaline earth azides, we incorporate Mg into the P/N framework to increase the degree of condensation κ to 0.6, the highest observed value for alkaline earth nitridophosphates. The crystal structure was elucidated by single-crystal X-ray diffraction, powder X-ray diffraction, energy-dispersive X-ray spectroscopy (EDX), and solid-state NMR. DFT calculations were performed on the title compounds and other related highly condensed nitridophosphates to investigate the influence of Mg in the P/N network. Eu2+-doped samples of the solid solution series show a tunable narrow-band emission from cyan to green (492-515 nm), which is attributed to the preferred doping of a single crystallographic site. Experimental confirmation of this assumption was provided by overdoping experiments and STEM-HAADF studies on the series as well on the stoichiometric compound Ba2Eu[Mg2P10N20] with additional atomic resolution energy-dispersive X-ray spectroscopy (EDX) mapping.

A simplification of intricate multifocal electroretinogram understanding: A mini-review.

Variation of multifocal electroretinogram (mfERG) data presentation in existing scientific publications is a challenge for eye care practitioners to apply the scientific information for evidence-based practice in patient management. This review offers an overview of the mfERG data presentation types. Eight types of data presentation in the form of a table, scatter plot, line graph, bar graph/box plot, single waveform/a group of waveforms, trace array topography, three-dimensional topography, and two-dimensional topography are identified. The table format is used to provide the exact values. Line graphs, scatter, and box plots offer information about the relationship of mfERG values. Waveforms are helpful for comparison between groups or conditions. Topographies outline the retinal, especially the specific localized retinal abnormalities. An infographic of fundamental mfERG electrical response with definitions and clinical indications is provided to bridge the gap between researchers and clinicians to facilitate efficient clinical application.

Render lighting dataset: A collection of rendered images with varied lighting conditions using blender render engines.

The quality of datasets is crucial in computer graphics and machine learning research and development. This paper presents the Render Lighting Dataset, featuring 63,648 rendered images of Blender's primitive shapes with various lighting conditions and engines. The images were created using Blender 4.0's Cycles and Eevee Render Engines, with careful attention to detail in texture mapping and UV unwrapping. The dataset covers six different lighting conditions, including Area Light, Spotlight, Point Light, Tri-Light, HDRI (Sunlight), and HDRI (Overcast), each adjusted using Blender's different options in the Color Management panel. With thirteen unique materials, ranging from Coastal Sand to Glossy Plastic, the dataset provides visual diversity for researchers to explore material properties under different lighting conditions using different render engines. This dataset serves as a valuable resource for researchers looking to enhance 3D rendering engines. Its diverse set of rendered images under varied lighting conditions and material properties allows researchers to benchmark and evaluate the performance of different rendering engines, develop new rendering algorithms and techniques, optimize rendering parameters, and understand rendering challenges. By enabling more realistic and efficient rendering, advancing research in lighting simulation, and facilitating the development of AI-driven rendering techniques, this dataset has the potential to shape the future of computer graphics and rendering technology.

Recent Advances in Preparing Transparent Phosphor Ceramics for High-Index Color Rendering and High-Power Lighting.

In recent years, high-power white light-emitting diode (wLED)/laser diode (wLD) lighting sources based on transparent phosphor ceramic (TPC) materials have attracted increasing application interest in automotive headlights, projection displays, and space navigation lighting due to their superior brightness, lighting distance, compactness, lifespan, and environmental resistance compared with the widely used phosphor-converted wLEDs. However, preparing TPC-converted wLEDs/wLDs with high color rendering index (CRI) remains a huge challenge, which limits their widespread application. In this review, we summarize the recently adopted strategies for constructing TPCs to develop high-power wLEDs/wLDs with high CRI values (>75). The construction protocols were categorized into four groups: host regulation, red-emitter doping, host regulation/red-emitter doping combination, and composite structure design. A comprehensive discussion was conducted on the design principles, photoluminescent properties, and device performances for each strategy. The challenges and future trends of high-power and high-CRI wLEDs/wLDs based on TPCs are also discussed toward the end of this review.

Phosphate phosphors with anti-thermal quenching properties for urban ecological lighting.

White light-emitting diode (LED) for night lighting disrupts photoperiod in plants, which affects the plant's photosynthesis. Therefore, it is necessary to find a new type of white LED with little effect on plant photosynthesis. In this study, a series of phosphate phosphors Ca9NaY2/3(PO4)7:Dy3+ (CNYP:Dy3+) were synthesized. Cation Li+ substitute Na+ were used to improve the luminescence properties of CNYP:Dy3+ phosphor. The CNYP:Dy3+ phosphor exhibits visible white light emission with emission peaks at 480 nm (blue light) and 570 nm (yellow light) excited by the near ultraviolet light 350 nm. The optimal concentration of Dy3+ was 0.10 mol, and the mechanism of concentration quenching was evaluated as energy migration among the nearest or next-nearest Dy3+. The substitution of Na+ by Li+ of CNYP:0.10Dy3+ improves the internal quantum efficiency from 30.24 % to 59.05 %, and presents good near-zero thermal quenching performance at 423 K. To assess the suitability of this phosphor for urban ecological lighting, the spectrum resemblance (SR) index between the electroluminescence spectrum of the prepared pc-LED and the absorption spectra of chlorophyll a and b was evaluated as 6.63 % and 18.61 %, respectively. This work exhibits a feasible scheme for the development of urban ecological lighting.

Robust, Narrow-Band Nanorods LEDs with Luminous Efficacy > 200 lm/W: Next-Generation of Efficient Solid-State Lighting.

Energy-efficient white light-emitting diodes (LEDs) are in high demand across the society. Despite the significant advancements in the modern lighting industry based on solid-state electronics and inorganic phosphor, solid-state lighting (SSL) continues to pursue improved efficiency, saturated color performance, and longer lifetime. Here in this article, robust, narrow emission band nanorods (NRs) are disclosed with tailored wavelengths, aiming to enhance the color rendering index (CRI) and luminous efficacy (LE). The fabricated lighting device consists of NRs of configuration CdSe/ZnxCd1-xS/ZnS, which can independently tune CRI R1-R9 values and maximize the luminous efficacy. For general lighting, NRs with quantum yield (QY) up to 96% and 99% are developed, resulting in ultra-efficient LEDs reaching a record high luminous efficacy of 214 lm W-1 (certified by the National Accreditation Service). Furthermore, NRs are deployed onto mid-power (0.3 W@ 50 mA) LEDs, showing significantly enhanced long-term stability (T95 = 400 h @ 50 mA). With these astonishing properties, the proposed NRs can pave the way for efficient lighting with desired optical spectrum.

Protein plant factories: production and resource use efficiency of soybean proteins in vertical farming.

BACKGROUND: Controlled environment agriculture, particularly vertical farms (VF), also called plant factories, is often claimed as a solution for global food security due to its ability to produce crops unaffected by weather or pests. In principle, essential macronutrients of the human diet, like protein, could technically be produced in VF. This aspect becomes relevant in the era of protein transition, marked by an increasing consumer interest in plant-based protein and environmental challenges faced by conventional farming. However, the real question is: what does the cultivation of protein crops in VF imply in terms of resource use? To address this, a study was conducted using a VF experiment focusing on two soybean cultivars. RESULTS: With a variable plant density to optimize area use, and because of the ability to have more crop cycles per year, protein yield per square metre of crop was about eight times higher than in the open field. Assuming soy as the only protein source in the diet, the resources needed to get total yearly protein requirement of a reference adult would be 20 m2 of crop area, 2.4 m3 of water and 16 MWh of electricity, versus 164 m2, 111 m3 and 0.009 MWh in the field. CONCLUSIONS: The study's results inform the debate on protein production and the efficiency of VF compared to conventional methods. With current electricity prices, it is unlikely to justify production of simple protein crops in VF or promote it as a solution to meet global protein needs. © 2024 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Solution approach using heuristic and artificial neural networks methods in assembly line balancing problems: A case study in the lighting industry.

Assembly line efficiency is one of the most important parameters that determine the overall efficiency of a manufacturing company. The production of a product under optimum conditions is ensured by a balanced assembly. With a balanced assembly line, machinery, material and labour costs are reduced. Within the scope of this research, real data about the daily production capacity and assembly line efficiency of a company producing Emergency Luminaire were taken, the same assembly line was balanced with 4 different Heuristic ALB methods and the results were compared. According to the results obtained, a high line efficiency of 93.955% was achieved using the Hoffman, Comsoal and Moodie&Young (M&Y) methods, and 84.414% was achieved with the Ranked Positional Weight (RPW) method. As a result of this, it was observed that the daily production capacity increased from 250 units to 375 units. As a result of the study, it was revealed that the efficiency of the existing assembly line and accordingly the daily production capacity increased. In addition, the study results of this assembly line were taught to an artificial neural network model for training purposes, and the work station results of the operations of a different assembly line were obtained with 99.940 accuracy. In this context, it has been revealed that the artificial neural networks method can be used in addition to the use of the heuristic method in the solution of ALB problems.

Smart home system using blockchain technology in green lighting environment in rural areas.

Currently, with the rapid development of smart home technology, the demand for establishing efficient and sustainable smart home systems in rural areas is increasing. However, in rural environments, the effective management and intelligent control of green energy face many challenges. To address these issues, this work aims to design a smart home system based on blockchain technology to achieve efficient energy management and intelligent control in a green lighting environment in rural areas. The main goals include improving the performance and safety of the system to meet the lighting needs of rural areas and promote sustainable development. The system comprises two primary components: the home gateway and cloud services. These components encompass functions like data monitoring and transmission, cloud storage, and remote control. The work also introduces the structural interaction, user node interaction, and the data security transmission scheme of the smart home system. Ultimately, the system's effectiveness is confirmed through simulation experiments. The results demonstrate that the system achieves the lowest latency when the transaction arrival rate is 40tps and the block size is 10. Additionally, the access control scheme based on the Hyperledger Fabric consortium chain can efficiently handle access requests for smart home resources and meet the practical application requirements within an appropriate range of security parameters. The main research conclusion is that the designed smart home system based on blockchain technology has achieved significant results in improving performance and security. This not only provides reliable lighting solutions for rural areas, but also provides important theoretical and practical guidance for the future development of smart home systems. The direction of future work includes further optimizing system performance, expanding the scope of application, and exploring more advanced blockchain technology applications in the field of smart homes. This will provide more possibilities and innovative directions for the development of future smart home systems.

The Energy Requirement for Supplemental Greenhouse Lighting Can Be Reduced by Considering 'Excess' Light from the Previous Day.

The sunlight greenhouse crops receive varies and is often insufficient for consistent year-round growth in greenhouses. Supplemental lighting is commonly applied in winter, but this practice has a significant energy cost, accounting for 10-30% of operating expenses and impacting greenhouse profitability. Greenhouse lights are traditionally adjusted based on sunlight intensity to meet crops' daily light requirements. However, if plants can withstand lower daily light integrals (DLI) after a sunny day without reducing the growth, there is potential to reduce the energy required for supplemental lighting and increase the profit. To determine whether excess light received one day can be 'carried over' to the next, we grew oakleaf lettuce (Lactuca sativa 'Green Salad Bowl' and 'Red Salad Bowl') under six lighting regimes inside a vertical farm. Plants in all treatments received an average DLI of 15 mol·m-2·d-1, but DLIs alternated from day-to-day (15/15, 17.5/12.5, 20/10, 22.5/7.5, 25/5, and 27.5/2.5 mol·m-2·d-1), resulting in DLI fluctuations from 0 to 25 mol·m-2·d-1. Plants had similar leaf area (~800 cm2/plant) and dry weight (~1.8 g/plant) when grown with DLI fluctuations from 0 to 15 mol·m-2·d-1, while higher DLI fluctuation reduced growth. To confirm this DLI "carrying-over" effect on plants grown under sunlight with supplemental light, we conducted a second study in a greenhouse with 'Green Salad Bowl' lettuce. In this study, plants were grown with five different DLI fluctuations (15/15, 16.75/13.25, 18.5/11.5, 20.25/9.75, and 22/8 mol·m-2·d-1), ranging from 0 to 14 mol·m-2·d-1, while maintaining an average DLI of 15 mol·m-2·d-1 in all the treatments. We observed similar leaf area (~750 cm2/plant) and dry weight (~1.8 g/plant) in lettuce plants grown with DLI fluctuations from 0 to 10.5 mol·m-2·d-1. Higher DLI fluctuations reduced growth. Hence, carrying excess light from a sunny to an overcast day is possible within limits. Our study concluded that the DLI requirement can be reduced by approximately 5.25 mol·m-2·d-1 on the day following a sunny day. By analyzing historical weather data from five US locations, we quantified the potential annual energy savings from incorporating this 'carrying-over DLI' concept. This approach resulted in annual energy savings of approximately 75-190 MWh/ha in greenhouse lettuce production. Such reductions in supplemental lighting energy will enhance the profitability and sustainability of the greenhouse industry.

Nanoparticle Effects on Ice Plant Mineral Accumulation under Different Lighting Conditions and Assessment of Hazard Quotients for Human Health.

Nanotechnologies can improve plant growth, protect it from pathogens, and enrich it with bioactive and mineral substances. In order to fill the lack of knowledge about the combined environmental effects of lighting and nanoparticles (NPs) on plants, this study is designed to investigate how different HPS and LED lighting combined with CuO and ZnO NPs influence the elemental composition of ice plants (Mesembryanthemum crystallinum L.). Plants were grown in hydroponic systems with LED and HPS lighting at 250 ± 5 µmol m-2 s-1 intensity, sprayed with aqueous suspensions of CuO (40 nm, 30 ppm) and ZnO (35-45 nm, 800 ppm) NPs; their elemental composition was measured using an ICP-OES spectrometer and hazard quotients were calculated. LED lighting combined with the application of ZnO NPs significantly affected Zn accumulation in plant leaves. Cu accumulation was higher when plants were treated with CuO NPs and HPS illumination combined. The calculated hazard quotients showed that the limits are not exceeded when applying our selected concentrations and growth conditions on ice plants. In conclusion, ice plants had a more significant positive effect on the accumulation of macro- and microelements under LED lighting than HPS. NPs had the strongest effect on the increase in their respective microelements.

Exploring effective light spectral conversion techniques for enhanced production of Spirulina-derived blue pigment protein, c-phycocyanin.

Spirulina is a promising feedstock for c-phycocyanin, a blue pigment-protein, commercially incorporated in many food products for its desirable bright blue attributes, exceptional bioavailability, and inherent therapeutic properties. Remarkably, enhancing c-phycocyanin synthesis in Spirulina would facilitate economic viability and sustainability at large-scale production, as the forecasted market value is $ 409.8 million by 2030. Notably, the lighting source plays a key role in enhancing c-phycocyanin in Spirulina, and thus, strategies to filter/concentrate the photons of respective wavelengths, influencing light spectra, are beneficial. Enveloping open raceway ponds and greenhouses by luminescent solar concentrators and light filtering sheets enables solar spectral conversion of the sunlight at desirable wavelengths, emerges as a promising strategy to enhance synthesis of c-phycocyanin in Spirulina. Nevertheless, the conduction of techno-economic assessments and evaluation of scalability at large-scale cultivation of Spirulina are essential for the real-time implementation of lighting strategies.