Use In Light-emitting Diodes Research Articles

Exploiting the Synergistic Effect of Kairomones and Light-Emitting Diodes on the Attraction of Phlebotomine Sand Flies to Light Traps in Brazil.

The synergistic effect of light-emitting diodes (LEDs) and kairomones on the attraction of sand flies to light traps was evaluated. Octenol and lactic acid were used as chemical attractants. Green LEDs and the incandescent lamps were used as light attractants. Five CDC-type light traps with the respective combination of attractants (incandescent lamp, incandescent lamp + chemical attractant, green LED, green LED + chemical attractant, and chemical attractant alone [without light]) were set between 18:00 and 06:00 following a Latin square design. A total of 6,536 sand flies and 16 species were collected. The most frequent species collected was Lutzomyia longipalpis (Lutz & Neiva, 1912) (Diptera, Psychodidae) accounting for 43.21% of all individuals. Order of success (mean, SD) of lactic acid attractant fly capture was as follows: LED + lactic acid (36.83 ± 4.74), LED alone (34.87 ± 4.61), incandescent lamp + lactic acid (22.80 ± 3.19), incandescent lamp alone (12.67 ± 2.03), and lactic acid (0.46 ± 0.13). Order of success of octenol attractant fly capture was as follows: LED + octenol (37.23 ± 5.61), LED alone (35.77 ± 5.69), incandescent lamp + octenol (18.63 ± 3.28), incandescent lamp alone (14.67 ± 2.86), and octenol alone (1.80 ± 0.65). With exception of lactic acid + incandescent light, chemical synergists played no part in significantly increasing light trap capture of phlebotomine sand flies. However, the use of LEDs, with or without such attractants, provided significantly higher capture compared to the incandescent lamp with or without such chemicals, showing that LEDs are suitable and efficient light sources for surveillance and monitoring of phlebotomine sand flies in Brazil.

LED light quality intensifies leaf pigmentation in ornamental pot plants

Light stimulates the production of anthocyanins in leaves. Assimilation light is needed in the production of red colored foliage plants during the dark winter period in order to obtain a commercially attractive product. In this study we tested whether this can be achieved by growing those plants for a limited period at the end of the production cycle in a growth chamber under specific LED (Light Emitting Diodes) light spectra. The experiment was conducted on three species: Hypoestes phyllostachya ‘decor pink’ and ‘decor red’ or polka dot plant, Guzmania lingulata ‘Theresa’ with yellow and red bracts and Cryptanthus carnosus ‘Tricolor’, also known as earth star. Different combinations of blue, red and far red light were applied and control treatments were given with and without HPS (High Pressure Sodium) lamps in the greenhouse. In all three species a minimal amount of blue light is compulsory. When only red LEDs are used in Hypoestes, leaves become curly and plants are not sufficiently compact. Without the addition of blue light the Guzmania bracts turn entirely yellow and Cryptanthus leaves are much more pale. In all cases, the use of LED was an improvement for the anthocyanin content when compared to plants that were grown without supplementary light. We demonstrated that for all three species a limited growing period under specific light spectra at the end of the production cycle can be a good way to produce attractive colored foliage plants when natural light is limited.

Antimicrobial efficacy of photodynamic therapy using two different light sources on the titanium-adherent biofilms of Aggregatibacter actinomycetemcomitans: An in vitro study.

Antimicrobial photodynamic therapy (aPDT), is a promising approach proposed as an adjunct for the decontamination of dental implant surfaces. This study aimed to investigate the effect of aPDT with laser or light emitting diode (LED) compared with conventional chlorhexidine treatment on the titanium-attached biofilms of Aggregatibacter actinomycetemcomitans. Thirty-six acid-etched and sandblasted (SLA) titanium discs were allocated to six groups and incubated with the titanium-adherent biofilms of A. actinomycetemcomitans as follows. Negative control (no treatment applied), positive control (0.2% chlorhexidine solution), 0.1 mg/mL Toluidine Blue [TBO] group, aPDT-treated groups subjected either to diode laser with a wavelength of 635 nm wavelength or LED with the peak wavelength of 630 nm with TBO as photosensitizer and sterile control (not contaminated). Following sonication and transferring the specimens to the microplate, the number of colony-forming units (CFUs) per disc was calculated. Data were analyzed using one-way analysis of variance (ANOVA) and additional post hoc tests with the level of significance set at P < 0.05. aPDT using TBO + LED was significantly more effective (0.93 ± 0.24 × 104) in the suppression of A. actinomycetemcomitans compared with TBO + Laser (2.65 ± 0.7 × 104). However, the lowest mean of CFU count was found in sterile, and chlorhexidine groups, respectively (P < 0.0001) and the highest bacterial count was observed in the negative control group (P < 0.0001). LEDs and diode lasers have a lower ability to suppress A. actinomycetemcomitans biofilms compared to 0.2% chlorhexidine in vitro. However, the aPDT with the use of LED as a light source and TBO as a photosensitive agent could be an appropriate alternative to conventional chlorhexidine treatment.

Effects of daytime intra-canopy LED illumination on photosynthesis and productivity of bell pepper grown in protected cultivation

In the past decade, light-emitting diodes (LEDs) have been replacing most other types of light sources. One emerging use for LEDs in horticulture is ‘intra-canopy illumination’ or ‘LED-interlighting’, feasible owing to their low heat output and small physical size. The interlighting technique, typically implemented in environmentally-controlled greenhouses also supplemented with overhead lighting, is mostly relevant for high-wire vegetable cultivation, in which self-shading results in light limitations for a large fraction of the canopy. Interlighting has been shown to increase the yield and/or improve fruit quality in all-year round greenhouse crops such as tomato, cucumber and sweet pepper. In this work, we utilized daytime supplemental intra-canopy LED illumination for sweet pepper grown in high-density ‘Spanish’ trellis systems within passive high tunnels in the Jordan Valley, Israel (latitude ˜32 °N). While canopy top at these conditions is not light-limited, extensive deep shading of the inner canopy is a disadvantage. In two experiments carried out in two separate seasons, the supplemental lighting, which enhanced the photosynthetic rates of the inner canopy foliage by 3.5- to 5.7-fold, resulted in significant increase (˜30%) of the fruit yield during the spring season. The added yield was attained by higher fruit numbers, with no notable effects on fruit size or weight. Our results raise the prospect that LED-interlighting may be a useful practical tool for maximizing fruit production, even in geographical regions of ample sunlight.

Microalgae and sustainable wastewater treatment: a Review

Microalgae play important roles in the realisation of energy-efficient carbon-neutral wastewater treatment. This is achievable through coupling carbon capture with wastewater treatment and consequent biomass production. Unlike activated sludge, microalgal biomass is more of a resource than a waste. This paper presents a review on the use of microalgae in sustainable wastewater treatment including organic matter, nitrogen, phosphorus and heavy metals removal. The paper also focussed on microalgal cultivation systems and the potentials of using microalgal photosynthesis in satisfying bacterial oxygen requirements in hybrid algae-bacteria systems. The use of light-emitting diodes in microalgal photosynthesis and their prospects as promising light sources in hybrid algal wastewater treatment systems was also presented.Keywords: Bacteria; carbon capture; hybrid wastewater treatment systems; light-emittingdiodes; microalgae

Optimization of LED Lighting and Quality Evaluation of Romaine Lettuce Grown in An Innovative Indoor Cultivation System

Sustainability is the most critical point in micro-scale indoor crop systems. It can be improved through the optimization of all of the production factors, such as water, nutrients, and energy. The use of light-emitting diodes (LED) allows the fine regulation of the light intensity and light spectrum to be obtained, with a significant reduction in energy consumption. The objective of this study was the optimization of a LED-based protocol of light management for Romaine lettuce cultivation in a micro-growing environment specifically designed for home cultivation. Four different growing cycles were tested. In each one, the light spectrum was modified by increasing the percentage of red light and decreasing the blue light. This resulted in a change in the light intensity which ranged from 63.2 to 194.54 µmol m−2 s−1. Moreover, the photoperiod was shortened to reduce the energy consumption and, in the last cycle, the effect of the daily alternation of dark and light was tested. The fresh and dry biomass produced were measured and the energy consumed in each cycle was monitored. The quality of lettuce was evaluated by measuring several physiological indexes, including chlorophyll a fluorescence, chlorophyll, sugars, nitrate, lipid peroxidation, carotenoids, and phenolic index. The results obtained showed that the productivity and the quality of lettuce can be positively affected by modulating the light quality and intensity, as well as other cultural practices. At the same time, the estimation of the electrical energy consumption indicated that little changes in the lighting recipe can significantly affect the energetic, environmental, and economic impact of home productions.

Analysis of the Algae Growth Dynamics in the Hydroponic System with LEDs Nighttime Lighting Using the Laser Granulometry Method

The latest research focused on the analysis of algal growth and the dynamics of their growth use the laser diffraction technique, enabling determination of the volume fraction of suspended particles with specific diameters in aqueous solution as well as their fractal dimensions. This study focuses on the possibility of using a laser granulometer to assess the growth dynamics of algae growing in treated wastewater in a hydroponic system, supported by artificial lighting with the use of light-emitting diodes (LEDs). On the basis of the measurements, the fractal dimension (Df) of algae was determined. An attempt was made to apply the modified Avrami equation describing the crystallization process for the analysis of algae growth dynamics in wastewater. Presented results show that the fractal dimension of suspended matter, largely created by algae, in the case of additional lighting of the hydroponic system at night, takes lower values (Df ~ 1.0) than in sewage without additional light source (Df ~ 2.0). In each measurement series, the fractal dimension of particles in the tank with lighting in the end of the experiment was about 33–43% lower than in the tank without LEDs. The analysis of changes in particle diameters calculated on the basis of Avrami equation largely corresponds with the stages of algae growth. During the measurement series with lower air temperatures, the growth of algae in the tank with additional light was faster than in the tank without LEDs. The obtained information can be the basis for determining the effective method of removing algae from wastewater treated in the hydroponic system, before they are discharged to the receiver in order to prevent the outflow of increased concentrations of total suspended solids.

Silicon-Doped Diamond-Like Composite Film to Improve the Thermal Dissipated Performance of Light-Emitting Diode

With the progress of light-emitting diodes (LEDs) research deepening, LEDs are gaining more and more widespread. During the use of LED, the excessive temperature of the P-N junction has a bad influence on the life of the LED. In order to reduce the junction temperature of the LED, efficient thermal management has become the key to the popularity of LEDs. The graphite materials are promising thermal conductivity material due to their superior thermal conductivity. In this experiment, Al/AlCX/Diamond-like carbon (DLC) composite film was coated on the surface of the LED substrate by direct current (DC) sputtering and radio frequency (RF) magnetron sputtering. On studying the effect of this composite film on the thermal dissipation performance of LED, the results show that the Al/AlCX/DLC composite film can effectively improve the thermal conductivity of the LED and reduce the thermal resistance. When the LED was driven using a 350-mA drive current, the thermal resistance of the uncoated device was 36.69 K/W and the thermal resistance of the coated device was 30.06 K/W. Compared with the uncoated device, the thermal resistance of the coated device is reduced by 18.1% and the junction temperature is reduced by 4.27 °C.

LED light use for the improvement of wastewater treatment in the hydroponic system

ABSTRACTEffective removal of nitrogen and phosphorus from sewage before its discharge to the receiving water body is now a key task for scientists and technologists around the world. The widespread problem of eutrophication in the watercourses as well as in the seas and oceans obliges to take actions leading to more effective protection of water resources and implementation of sustainable development principles. One of the methods of increased wastewater treatment from nutrients is the use of a third stage of treatment with the use of macrophytes for the uptake of nitrogen and phosphorus. These systems, called hydroponic, under moderate climate conditions show little effectiveness due to the lack of sufficient light intensifying the growth of aquatic plants. The aim of this study was to evaluate the reduction of biogenic compounds concentrations in wastewater where additional lighting of plants was provided by the use of LED (Light Emitting Diodes), in two different conditions of experiment: with aeration and with carbon dioxide supplementation. Analyses show that the effectiveness of purification was higher in the wastewater supplemented with CO2 and artificial lighting had no significant influence on the reduction of nitrogen forms concentrations. In wastewater with aeration, higher effectiveness of nitrogen removal was observed in the tank with artificial lighting. In both cases, aeration or CO2 supplementation as well as artificial lighting or its lack, had no influence on total phosphorus and phosphates removal.

Continuous Irradiation with Alternating Red and Blue Light Enhances Plant Growth While Keeping Nutritional Quality in Lettuce

Plant factories with artificial lighting have been developed to improve food production, functional ingredients, and profitability. Intensive research has been performed to elucidate the effects of light intensity and wavelength on plant growth and nutritional quality with the use of light-emitting diodes (LEDs). In particular, the effects of monochromatic red, blue, or simultaneous red + blue light have been studied because these wavelengths are predominantly used for photosynthesis. We examined the effects of alternating red and blue light provided by LEDs over a period of 24 hours on the growth and nutritional properties of leafy lettuce. The results clearly show that alternating red and blue light accelerated plant growth significantly compared with white fluorescent lamps or red and blue LEDs at the same daily light integral. Plants grown under alternating red/blue light had a greater net assimilation rate and total and projected leaf area (an indicator of the fraction of leaf area that absorbs more light) than other plants. Additionally, alternating red and blue light maintained high concentrations of sugars, ascorbic acid, and anthocyanins in leaves. Taken together, the results indicate that continuous irradiation with alternating red and blue light could enhance growth while maintaining the nutritional quality in lettuce.

Circular Economy Aspects Regarding LED Lighting Retrofit—from Case Studies to Vision

The lighting industry is still a linear economy, despite the extensive use of light-emitting diode (LED) and the ban of incandescent/halogen lamps, claiming to be greener and more human centered. Light-emitting diode has changed radically the whole lighting industry with an increased luminaire efficacy more than four times higher compared with fluorescent lamps and their new opportunities for modern control systems. In the years to come, millions of fluorescent luminaires will become waste and will be replaced by LED luminaires. According to the Cost European Cooperation in Science &amp; Technology Program the next step will be from sustainability to regenerative (enabling social and ecological systems to maintain a healthy state and to evolve) and to get there, circular economy is essential. In order to reduce even further the carbon footprint, the retrofit of existing luminaires and additional modern control systems should be the solution. Circular economy aspects for the lighting area were identified using the university adopted lighting retrofit solutions as case studies. For an LED retrofitted recessed luminaire 4 × T8 18 W studies showed a major installed power reduction, a good lighting distribution, but also revealed some problems: the retrofit luminaire has no certification, necessity of qualified personnel, high labor costs, etc. A major issue is the fact that luminaire design did not take into consideration circular economy aspects like the possibility of future retrofit solutions. It is important that from now on a different approach should be foreseen for the LED luminaire design. There is a section about vision, which plays an important role in preparing new luminaire generations with circular economy in mind.

Light Emitting Diode (LED) as an essential prop component for STEM education in the 21st century: A focus for secondary school level

Indonesian secondary science curriculum is often late to keep up with the rapid development of technology. For instance, the widely-used LED (Light Emitting Diode) technology is not familiar as props in secondary science instructions in Indonesia. This study aims to: (1) provide professional development for teachers in developing experiments using LEDs for learning physics concepts, and (2) increase teachers’ beliefs on their knowledge on using LEDs for physics experiments. The professional development only used a single group pre- and post-test research design in the form of a two-day workshop attended by 20 science teachers from secondary level schools in the city of Banda Aceh. The workshop used Investigative Science Learning Environment (ISLE)-STEM approach, an inquiry-based physics learning that incorporate STEM education approach in active learning and collaboration. The workshop used LEDs as experimental props. From the qualitative analysis of the pre- and postquestionnaires’ responses, we found that there are positive improvements on participants’ understanding of ISLE-based STEM approach and of the use of LEDs as props. From the questionnaire administered after the workshop, we found that most of the teachers were excited about the training using LED as props and 89.4% of them feel that their knowledge increased.

Efficacy of diode-emitting diode (LED) photobiomodulation in pain management, facial edema, trismus, and quality of life after extraction of retained lower third molars: A randomized, double-blind, placebo-controlled clinical trial.

Background:In dentistry, one of the most common surgical procedures is the removal of retained third molars. This surgery generates great morbidity to the participants for causing pain, edema, and trismus due to surgical trauma. The objective of the present study is to evaluate the efficacy of photobiomodulation with light emitting diode (LED) in the control of pain, facial edema, trismus, and quality of life resulting from the extraction of retained lower third molars.Methods:A randomized, double-blind, placebo-controlled clinical trial involving 38 adult participants, who meet the criteria of eligibility and agree to participate in the study. Before the surgeries are performed, the facial and mouth opening measures of all the participants will be taken. Immediately after the surgeries, participants will be randomized into 2 groups. In the LED group, participants will receive LED applications (intra oral with 660 nm, 12J and extraoral with 850 nm, 108J) in the immediate postoperative, first and second days after the surgical procedure. In the control group, the participants will be attended in the same way as in the LED group, however, the person in charge of the application will simulate the irradiation. Pain (EVA and NRS-101), postoperative edema, trismus, temperature, dysphagia, and hematoma will be evaluated after 1, 2, 5, and 7 days. The oral health impact profile (OHIP-14 Questionnaire) and anxiety analysis (Beck anxiety inventory -BAI) questionnaires will be applied preoperatively and 7 days after treatment. The appropriate statistical tests will be applied for each specific analysis in a significance level of 5%.Discussion:Although the use of low-power laser in the postoperative has shown good results in the control of postoperative sequelae, this is the first study on the efficacy of the use of LED in this situation.

Photodynamic and photobiological effects of light-emitting diode (LED) therapy in dermatological disease: an update

Benefit deriving from the use of light is known since ancient time, but, only in the last decades of twentieth century, we witnessed the rapid expansion of knowledge and techniques. Light-emitted diode (LED)-based devices represent the emerging and safest tool for the treatment of many conditions such as skin inflammatory conditions, aging, and disorders linked to hair growth. The present work reviews the current knowledge about LED-based therapeutic approaches in different skin and hair disorders. LED therapy represents the emerging and safest tool for the treatment of many conditions such as skin inflammatory conditions, aging, and disorders linked to hair growth. The use of LED in the treatment of such conditions has now entered common practice among dermatologists. Additional controlled studies are still needed to corroborate the efficacy of such kind of treatment.

Do Different LED Colours Influence Sand Fly Collection by Light Trap in the Mediterranean?

Light traps represent the most used attractive system to collect and monitor phlebotomine sand flies. Recent studies have suggested that light traps can be easily upgraded by the use of light-emitting diode (LED) with positive effects on trap design, weight, and battery life. However, scant data on the effect of different LED colours on the attractiveness to phlebotomine sand fly species are available in literature. In this study, the capture performances of light traps equipped with different LED colours on phlebotomine sand fly species indigenous in the Mediterranean area were evaluated. Phlebotomine sand fly collections were performed using a classical light trap (CLT), equipped with a traditional incandescent lamp, and five Laika 4.0 light traps supplied, each with LED of different colours and wavelengths: (i) white; (ii) red; (iii) green; (iv) blue; (v) UV. Light traps were set for three consecutive nights fortnightly from May to October 2017 and climate data recorded using a meteorological station. A total of 411 phlebotomine sand flies (191 males and 220 females), belonging to three different species, namely, Phlebotomus perniciosus (n= 298, 141 males and 157 females), Sergentomyia minuta (n=110, 48 males and 62 females), and Phlebotomus neglectus (n=3, 2 males and 1 females) were collected. Abundance of capture was influenced by colours of LED and time. The highest number of phlebotomine sand flies was captured on June (P<0.01) and by UV LED (P<0.01). As regard to species, P. perniciosus was mainly captured by UV LED on June (P<0.01). No effect of time (P>0.05) or LED colour (P>0.05) was recorded for S. minuta and P. neglectus. According to the results of the present study light trap equipped with UV LED can represent an effective tool for the capture of sand fly species in the Mediterranean area.

LED Lighting - Modification of Growth, Metabolism, Yield and Flour Composition in Wheat by Spectral Quality and Intensity.

The use of light-emitting diode (LED) technology for plant cultivation under controlled environmental conditions can result in significant reductions in energy consumption. However, there is still a lack of detailed information on the lighting conditions required for optimal growth of different plant species and the effects of light intensity and spectral composition on plant metabolism and nutritional quality. In the present study, wheat plants were grown under six regimens designed to compare the effects of LED and conventional fluorescent lights on growth and development, leaf photosynthesis, thiol and amino acid metabolism as well as grain yield and flour quality of wheat. Benefits of LED light sources over fluorescent lighting were manifested in both yield and quality of wheat. Elevated light intensities made possible with LEDs increased photosynthetic activity, the number of tillers, biomass and yield. At lower light intensities, blue, green and far-red light operated antagonistically during the stem elongation period. High photosynthetic activity was achieved when at least 50% of red light was applied during cultivation. A high proportion of blue light prolonged the juvenile phase, while the shortest flowering time was achieved when the blue to red ratio was around one. Blue and far-red light affected the glutathione- and proline-dependent redox environment in leaves. LEDs, especially in Blue, Pink and Red Low Light (RedLL) regimens improved flour quality by modifying starch and protein content, dough strength and extensibility as demonstrated by the ratios of high to low molecular weight glutenins, ratios of glutenins to gliadins and gluten spread values. These results clearly show that LEDs are efficient for experimental wheat cultivation, and make it possible to optimize the growth conditions and to manipulate metabolism, yield and quality through modification of light quality and quantity.

Discrete Indoor Three-Dimensional Localization System Based on Neural Networks Using Visible Light Communication.

Indoor localization estimation has become an attractive research topic due to growing interest in location-aware services. Many research works have proposed solving this problem by using wireless communication systems based on radiofrequency. Nevertheless, those approaches usually deliver an accuracy of up to two metres, since they are hindered by multipath propagation. On the other hand, in the last few years, the increasing use of light-emitting diodes in illumination systems has provided the emergence of Visible Light Communication technologies, in which data communication is performed by transmitting through the visible band of the electromagnetic spectrum. This brings a brand new approach to high accuracy indoor positioning because this kind of network is not affected by electromagnetic interferences and the received optical power is more stable than radio signals. Our research focus on to propose a fingerprinting indoor positioning estimation system based on neural networks to predict the device position in a 3D environment. Neural networks are an effective classification and predictive method. The localization system is built using a dataset of received signal strength coming from a grid of different points. From the these values, the position in Cartesian coordinates is estimated. The use of three neural networks is proposed in this work, where each network is responsible for estimating the position by each axis. Experimental results indicate that the proposed system leads to substantial improvements to accuracy over the widely-used traditional fingerprinting methods, yielding an accuracy above 99% and an average error distance of 0.4 mm.

Optical characterization of magnesium incorporation in p-GaN layers for core–shell nanorod light-emitting diodes

III-nitride nanostructures are of interest for a new generation of light-emitting diodes (LEDs). However, the characterization of doping incorporation in nanorod (NR) structures, which is essential for creating the p-n junction diodes, is extremely challenging. This is because the established electrical measurement techniques (such as capacitance–voltage or Hall-effect methods) require a simple sample geometry and reliable ohmic contacts, both of which are difficult to achieve in nanoscale devices. The need for homogenous, conformal n-type or p-type layers in core–shell nanostructures magnifies these challenges. Consequently, we demonstrate how a combination of non-contact methods (micro-photoluminescence, micro-Raman and cathodoluminescence), as well as electron-beam-induced-current, can be used to analyze the uniformity of magnesium incorporation in core–shell NRs and make a first estimate of doping levels by the evolution of band transitions, strain and current mapping. These techniques have been used to optimize the growth of core–shell nanostructures for electrical carrier injection, a significant milestone for their use in LEDs.

Influence of Closed Sandwich Technique on Marginal Seal of Class II Restorations with Different Substrates using LED Curing

This study was done to evaluate the microleakage at the tooth restoration interfacein different substrates when glass ionomer was used as a base which covered by aveneer of resin composite, as closed sandwich technique, with light -emitting diode(LED) curing.Eighty Class II cavities were prepared in mesial and distal of extracted molars,mesial cavities with gingival margins in enamel (E) and distal cavities with gingivalmargins in dentin(D), were divided into four main groups (G)s, each group wassubdivided into GE and GD of ten cavities for each and filled as follows:GI each cavity of GIE &amp; GID was filled with composite and cured with halogenlight curing unit (H), GII each cavity of GIIE &amp; GIID was filled with glass ionomerlining and composite and cured as GI, Group III each cavity of GIIIE &amp; GIIID wasfilled as GI but cured with LED while Group IV, each cavity of GIVE and GIVDfilled as GII and cured as GIII. After restorations, the teeth were thermocycled 300times, soaked in 0.1% methylene blue for 24 hours, sectioned and microleakage fromthe gingival margin scored. Statistical analysis was performed using t-test.There was no significant difference when use sandwich technique in enamel butThere was significant difference in dentin (p≤0.05), while no significant differencewhen the comparison between enamel and dentin, whether LED or H curing was used.With sandwich technique, the marginal adaptation of enamel margins was notdependent on the restorative technique while marginal adaptation in dentin wassignificantly better. The use of LED had no adverse effect on microleakage.

Current status and recent achievements in the field of horticulture with the use of light-emitting diodes (LEDs)

Abstract Light-emitting diode (LED) technology has rapidly advanced the past years and it is nowadays irrevocably linked with controlled-environment agriculture (CEA). We provide here an amalgamation of the recent research achievements in the horticulture and floriculture industry, ranging from greenhouse applications to climate rooms and vertical farming. We hope this overview bestows ample examples for researchers and growers in the selection of the appropriate LED light solution for amending crop yield, phytochemical content, nutritional value, flowering control, transplant success, pre-harvest and postharvest product quality, and production of regeneration material. We leave the reader with some future prospects and directions that need to be taken into account in this ever-growing field.