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Recent work has demonstrated that exposure to artificial light at night (ALAN) may alter mosquito feeding behavior and so must be considered a moderator of vector-borne disease transfer. Anopheles funestus mosquitoes are a primary malaria vector in sub-Saharan Africa, but no study to date has tested the impact of ALAN on their feeding behavior. Here we test if the exposure to commonly used household lights (compact fluorescent lights, light-emitting diodes, and incandescent lights) alters Anopheles funestus feeding. Mated, unfed female mosquitoes were exposed to a light treatment, at the onset of darkness, followed by a blood-feeding assay. The light treatments consisted of a 30-min light pulse of one of the three household lights, each in individual experimental containers, versus controls. All three household lights resulted in a reduction in the percentage of females taking a blood meal, but only mosquitoes exposed to incandescent light showed a statistically significant reduction in feeding of 19.6% relative to controls which showed a 42.8% feeding rate. Our results suggest that exposure to some household lights during the night may have an immediate inhibitory effect on Anopheles funestus feeding. By helping identify which light types lead to a suppression of feeding, the findings of this study could provide insight necessary to design household lights that can help minimize mosquito feeding on humans. [ABSTRACT FROM AUTHOR]

This study investigates the influence of LED radiation intensity on the photodeposition of gold nanoparticles onto TiO2 substrates, examining their physicochemical properties and photocatalytic activities. Utilizing a range of radiation intensities and wavelengths, TiO2-Au composites were synthesized and characterized through techniques such as X-ray diffraction (XRD), scanning electron microscopy (SEM) with energy dispersive X-ray (EDX), and X-ray photoelectron spectroscopy (XPS). The deposition process, markedly enhanced by shorter wavelengths and higher intensities, efficiently formed gold nanoparticles. This research distinctly highlights observable morphological changes in the nanoparticles; increased radiation intensity not only augmented the size but also altered their shape from spherical to hexagonal. These morphological transformations significantly improve the composites' light absorption and catalytic properties due to the surface plasmon resonance of the gold nanoparticles. Photocatalytic assessments, using metronidazole as a model pollutant, demonstrated that composites prepared with higher LED intensities showed significantly enhanced degradation capabilities compared to those synthesized with lower intensities. The findings underscore that manipulating photodeposition parameters can critically influence the structural and functional properties of TiO2-Au composites, potentially advancing their applications in environmental remediation and solar energy utilization. [ABSTRACT FROM AUTHOR]

Artificial seed production is a valuable technology for commercial plant production and provides a viable option for preserving elite plant germplasm. The objective of this study was to determine the optimal concentrations of sodium alginates (3%, 4%, and 5%) and calcium chloride (75 mM, 100 mM, and 150 mM) for encapsulating Phalaenopsis orchid protocorms. The second objective was to determine the optimal temperature (4, 20, and 25 °C), light spectra (blue, red, green, far-red, white, and darkness), and storage duration (30, 60, 90, and 180 days) for preserving synthetic seeds. The optimal alginate concentration for producing uniform, circular, and sufficiently strong artificial seeds with the highest germination percentage was found to be 4% in a 100 mM calcium chloride solution. The synthetic seeds stored at 25 °C for 180 days had the shortest germination initiation time (2.33 days), the highest germination percentage (100%), and the highest number of leaves, roots, and protocorm-like bodies. The study on synthetic seeds found that storing them in darkness for 90 days is the most effective treatment, considering the interaction between light spectra and storage period. It is recommended to use green light during storage only when quick germination is necessary. Key Message: Artificial seeds of Phalaenopsis made of 4% alginate with 100 mM CaCl2 had the highest germination rate. The best storage condition was 25 °C for 180 days under LED lights, particularly green light. [ABSTRACT FROM AUTHOR]

Magnetic photocatalyst [magnetic@silica@zinc manganate, Fe3O4@SiO2@ZnMn2O4] (MZMO) and [magnetic@silica@zinc manganate@copper tetra hydroxyl phenyl porphyrin, Fe3O4@SiO2@ZnMn2O4@CuIITHPP] (MZMOCuP) nanocomposites were prepared using green synthesis method and characterized by means of Fourier transform-infrared, scanning electron microscope, energy-dispersive X-ray spectroscopy, X-ray diffraction, vibrating sample magnetometer (VSM) and ultra-violent-diffuse reflectance spectroscopy techniques. The magnetic properties of the synthesized samples were measured by a VSM with maximum saturation magnetization values of 10 and 8 emu g−1 for MZMO and MZMOCuP nanocomposites, respectively. UV-diffuse reflectance spectroscopy data of MZMOCuP indicate the red shift of the absorption edge and reduction of the band gap from 1.4 to 1.1 eV in comparison with MZMO. The nanocomposite of MZMOCuP showed excellent photocatalytic activity for photodegradation of methylene blue (MB) in aqueous solution under visible-LED light irradiation. The degradation of MB was monitored by UV–Vis spectrophotometer. Maximum degradation of 98% for MB was obtained in the presence of MZMOCuP nanocomposite as the photocatalyst and under 180 min irradiation of 3 W blue LED light. The recovery of the photocatalyst was easily performed by using an external magnetic field. [ABSTRACT FROM AUTHOR]

The development of the scheme and the results of marine tests of a system for operational video surveillance of the vertical distribution of zooplankton "in situ" are presented for the example of works in the Kara Sea. [ABSTRACT FROM AUTHOR]

Photosensitizer MiniSOG (mini-singlet oxygen generator), a green fluorescent flavoprotein, can be used to kill cells in a spatially and temporally regulated manner according to a chosen promoter when it is fused with the target cells. However, it needs 470 nm blue light excitation to release reactive oxygen species (ROS) to work. In the past, researchers usually used fluorescence microscope to generate light, which wasted the lab resources and influenced other experiments. Here, we developed a homemade light emitting diode (LED) light for photo-inducible cell ablation by photosensitizers. The LED light consisted of six groups of lamps, and it could illuminate a plurality of culture dish drawers simultaneously with different light intensities. In order to watch the efficacy of cell ablation, confocal imaging, behavioral, calcium imaging and electrophysiology experiments have been performed on C. elegans. Most of neurons related with forward movements have been ablated after dozens of minutes light irradiation. The worms can only move backward with wriggled body, and the calcium oscillation increases in reverse movement motor neurons. The whole frequency and amplitude of miniature postsynaptic currents (PSCs) in body wall muscle decrease because of death of some neurons. These experimental results verified that the LED light was useful and convenient. This study provides a method for high-throughput cell ablation experiments. [ABSTRACT FROM AUTHOR]

This report describes a comparative study of dye degradation under 20-W LED light using the perovskite photocatalyst Calcium Copper Titanate (CCTO) and its compositions (CaxCu3-xTi4O12) (x = 1, 1.5 and 2), synthesized by changing molar ratios of Ca2+ and Cu2+ ions. The 99.74% degradation of Rhodamine Blue (RhB) with composition (x = 1) within 6 h is reflected its better photocatalytic activity than the parent CCTO and other compositions. The band gap energy of the materials 2.18 eV (CCTO), 1.93 eV (x = 1), 2.40 eV (x = 1.5), and 2.55 eV (x = 2) are analysed with UV–Vis spectroscopy. The presences of Ca, Cu, Ti and O in the synthesized photocatalysts are confirmed with Elemental X-ray Dispersive (EDX) analysis. The cubic phases in the polyhedral shape of the materials are detected in X-ray diffraction and Scanning Electron Microscopy (SEM). This report further observes the defect density concentrations of the materials with Photoluminescence Spectroscopy (PL) and provides the approximate explanation of their dye degradation performance as photocatalysts. The rate constants are found in a first order reaction trend; where the composition (x = 1) shows about 1.683 × 10–2 min−1. The mechanistic understanding of the degradation process is also revisited and rationalized with different scavengers for the process. [ABSTRACT FROM AUTHOR]

TiO2 is employed as both photocatalytic and structural materials, leading to its applications in external coatings or in interior furnishing devices, including cement mortar, tiles, floorings, and glass supports. The authors have already demonstrated the efficiency of photoactive micro-sized TiO2 and here its industrial use is reported using the digital printing to coat porcelain grés slabs. Many advantages are immediately evident, namely rapid and precise deposition, no waste of raw materials, thus positively affecting the economy of the process. Data for the thin films deposited by digital printing were compared with those obtained for the conventional spray method. The use of metal-doped TiO2 is also reported so that the photoactivity of these materials can be exploited even under LED light. The digital inkjet printed coatings exhibited superior photocatalytic performance owing to both higher exposed surface area and greater volume of deposited anatase, as well as the greater areal distribution density of thinly and thickly coated regions. Moreover, the presence of TiO2 doped silver increased the efficiency of the materials in NOx degradation both under UVA and LED lights. [ABSTRACT FROM AUTHOR]

Photocatalysis has been intensively used for wastewater remediation, but suffers from unsatisfactory efficiency for treating complex wastewater system, which includes antibiotic, organic dye and bacteria. Herein, we prepared novel SnO2−x/g-C3N4 photocatalysts and introduced oxygen vacancy by partial oxidation of Sn2+ under solvothermal condition. The oxygen vacancy was demonstrated by the X-ray photoelectron and electron spin resonance spectra. Compared with pure SnO2−x, g-C3N4 and stoichiometric SnO2/g-C3N4 composite, the optimum SnO2−x/g-C3N4 composite exhibited higher photoactivity for removing antibiotic (tetracycline hydrochloride) and organic dye (rhodamine B) under light-emitting diode (LED) track light irradiation. Furthermore, the optimum SnO2−x/g-C3N4 composite could completely inactivate Escherichia coli within 30 min. The remarkable performance of SnO2−x/g-C3N4 was mainly ascribed to oxygen vacancy: (i) enhanced the separation efficiency of photo-induced charge carriers between SnO2−x and g-C3N4; (ii) broadened light absorption range due to the formation of SnO2−x with narrow band gap. This work provides a new idea for designing g-C3N4-based photocatalyst with oxygen vacancy toward wastewater remediation. [ABSTRACT FROM AUTHOR]

In this paper, an indoor positioning method, namely LiPro, is proposed for handheld devices such as smartphones. Based on an empirical light intensity model, we propose a rotating multi-face positioning method that enables a receiver to locate itself in ill-conditioned scenarios which would otherwise make the traditional multilateration impossible-for example when less than three LED lamps are visible to the receiver. In this method, the user manually performs three rotations of the receiver around three orthogonal axes, in a manner similar to the calibration process of a compass. During this process, the receiver continuously collects RSS and magnetic field strength, which are then used to solve for the receiver's position. LiPro can work with a single source of light, making it a more cost-effective and less demanding than previous approaches. Our experiments show that LiPro achieves a median error of 0.59 m in a corridor with linearly deployed LEDs, and 0.45 m in an office. Moreover, LiPro is shown to be robust against interference from ambient light sources. [ABSTRACT FROM AUTHOR]

I studied the influence of various combinations of auxin and cytokinin concentrations, and the increased content of zinc and enzymatic casein hydrolizate in SH medium on initiation and proliferation of embryogenic callus of Abies nordmanniana (Steven) Spach. Additionally, the effect of ABA, PEG-4000 and different wavelengths on the maturation of somatic embryos was tested. The use of optimum composition of modified SH medium with BA, KIN and 2.4-D while simultaneously ensuring appropriate external conditions resulted in 15.5 % embryogenesis. Finally, satisfactory results of micropropagation of A. nordmanniana by somatic embryogenesis were obtained providing seven lines of embryogenic callus with high proliferation capacity. Those lines gave properly developed seedlings in white LED light with a wavelength of 400-700 nm, preceded by eight-week vernalization treatment of the callus. This paper may provide a protocol by which all stages of somatic embryogenesis of A. nordmanniana can be carried out, including the preceding 24-h seed disinfection with NaOCl and PVP, which resulted in 100 % frequency of uninfected zygotic embryos that were capable of starting embryogenesis. [ABSTRACT FROM AUTHOR]

A dual input LED lighting scheme with constant illumination is proposed in this paper. The scheme employs a photovoltaic array as the first input and a battery as the second one. A microcontroller is programmed to operate a changeover switch as well as a DC-DC converter for uninterrupted and constant illumination in work place. The scheme is suitable for conference halls, laboratories, clean rooms, marriage halls, theaters, etc. The complete modeling, design and experimentation of the proposed scheme are explained and the economic viability of the scheme is justified. [ABSTRACT FROM AUTHOR]

Microalgae are viable sources of biological compounds for biodiesel production. In this study, effects of various types of nitrogen sources and nutrients concentrations in the growth medium and different LED light wavelengths and intensities on biomass production of green algae Chlorella vulgaris were investigated. Warm white light with 80 µmol/m/sec light intensity was determined as the optimal light for biomass production. The results indicated that microalgae growth with urea as nitrogen source was higher than that of other nitrogen sources such as sodium nitrate, ammonium carbonate and ammonium chloride. Maximum biomass concentration (1.37 g/L) was obtained under the following media compositions: urea 0.25 g/L, KHPO 0.04 g/L, MgSO· 7HO 0.06 g/L, and ammonium ferric citrate 0.01 g/L. Microalgae growth data under the different light wavelengths and intensities were fitted with a mathematical model. [ABSTRACT FROM AUTHOR]

Hyperspectral imaging is useful for detecting internal defects of pickling cucumbers. The technique, however, is not yet suitable for high-speed online implementation due to the challenges in analyzing large-scale hyperspectral images. This research aimed to select the optimal wavebands from the hyperspectral image data, so that they can be deployed in either a hyperspectral or multispectral imaging-based inspection system for the automatic detection of internal defects of pickling cucumbers. Hyperspectral reflectance (400-700 nm) and transmittance (700-1,000 nm) images were acquired, using an in-house developed hyperspectral imaging system running at two conveyor speeds of 85 and 165 mm/s, for 300 'Journey' pickling cucumbers before and after internal damage was induced by mechanical load. Minimum redundancy-maximum relevance (MRMR) was used for optimal wavebands selection, and the loadings of principal component analysis (PCA) were also applied for qualitatively identifying the important wavebands that are related to the specific features. Discriminant analysis with Mahalanobis distance classifier was performed for the two-class (i.e., normal and defective) and three-class (i.e., normal, slightly defective, and severely defective) classifications using the mean spectra and textural features (energy and variance) from the regions of interest in the spectral images at selected waveband ratios. The classification results based on MRMR wavebands selection were generally better than those from PCA-based classifications. The two-band ratio of 887/837 nm from MRMR gave the best overall classification results, with the accuracy of 95.1 and 94.2 % at the conveyor speeds of 85 and 165 mm/s, respectively, for the two-class classification. The highest classification accuracies for the three-class classification based on the optimal two-band ratio of 887/837 nm were 82.8 and 81.3 % at the conveyor speeds of 85 and 165 mm/s, respectively. The mean spectra-based classification achieved better results than the textural feature-based classification, except in the three-class classification for the higher conveyor speed. The overall classification accuracies for all selected waveband ratios at the low conveyor speed were slightly higher than those at the higher conveyor speed, since the low speed resulted in more scan lines, thus higher spatial resolution hyperspectral images. The identified two-band ratio of 887/837 nm in transmittance mode could be applied for fast real-time internal defect detection of pickling cucumbers. [ABSTRACT FROM AUTHOR]

This study evaluated the shear bond strength (SBS) and adhesive remnant index (ARI) of ceramic brackets with different base designs using a 473-nm diode-pumped solid-state (DPSS) laser to test its usefulness as a light source. A total of 180 caries-free human premolars were divided into four groups according to the base designs: microcrystalline, crystalline particle (CP), dovetail, and mesh. For each base design, teeth were divided into three different subgroups for light curing using three different light-curing units (LCUs) (quartz-tungsten-halogen unit, light-emitting diode unit, and a DPSS laser of 473 nm). Applied light intensities for the DPSS laser and the other LCUs were approximately 630 and 900 mW/cm, respectively. Stainless steel brackets with a mesh design served as controls. The failure modes of debonded brackets were scored using ARI. As a result, brackets bonded using the DPSS laser had the highest SBS values (16.5-27.3 MPa) among the LCUs regardless of base design. Regarding base designs, the CP groups showed the highest SBS values (22.9-27.3 MPa) regardless of LCU. Furthermore, stainless steel brackets with a mesh design had the lowest SBS values regardless of LCU. In many cases, brackets bonded using the DPSS laser had higher ARI scores and had more adhesive on their bases than on tooth surfaces. The study shows that the 473-nm DPSS laser has considerable potential for bonding ceramic brackets at lower light intensities than the other light-curing units examined. [ABSTRACT FROM AUTHOR]

The aim of this study was to propose the use of red light-emitting diode (LED) as an alternative light source for methylene blue (MB) photosensitizing effect in photodynamic therapy (PDT). Its effectiveness was tested against Staphylococcus aureus (ATCC 26923), Escherichia coli (ATCC 26922), Candida albicans (ATCC 90028) and Artemia salina. The maximum absorption of the LED lamps was at a wavelength of 663 nm, at intensities of 2, 4, 6 and 12 J.cm-2 for 10, 20, 30 and 60 min of exposure, respectively. Assays with and without LED exposure were carried out in plates containing MB at concentrations of 7 to 140.8 μM for microorganisms and 13.35 to 668.5 μM for microorganisms or microcrustaceans. The LED exposure induced more than 93.05%, 93.7% and 93.33% of growth inhibition for concentrations of 42.2 μM for S. aureus (D-value=12.05 min) and 35.2 μM for E. coli (D-value=11.51 min) and C. albicans (D-value=12.18 min), respectively after 20 min of exposure. LED exposure for 1 h increased the cytotoxic effect of MB against A. salina from 27% to 75%. Red LED is a promising light device for PDT that can effectively inhibit bacteria, yeast and microcrustacean growth. [ABSTRACT FROM AUTHOR]

The article presents an analysis of visual perception of light emitting diode (LED) brightness in dense fog with various droplet sizes. It mentions that it is understood, through the measurement of the brightness of the LED, the particle size distribution and density of fog does affect visibility in fog. It reports that the finding can contribute to air and land traffic safety and the prevention of accidents.

The electromagnetic compatibility (EMC) of 400 MHz radio communications is an issue of growing interest, especially the EMC of wireless medical telemetry (WMT) in clinical settings. Electromagnetic interference (EMI) by radiation noise emitted from switched-mode power supplies built into light-emitting diode (LED) lights is now of considerable interest for the safe operation of WMT. Moreover, the 400 MHz frequency bands that are allocated for WMT are also shared and used for other radio communication systems. In this work, we studied the EMI problem of WMT used in Japan. We experimentally investigated EMI with WMT caused by electromagnetic noise emitted from LED lights. In addition, we suggested countermeasures for these EMI issues and the management of an electromagnetic environment by a very simplified method. [ABSTRACT FROM AUTHOR]

The article describes a method for determination of tannic acid in extracts of medicinal plants. Tannic acid (TA) is an antioxidant and has anticancer and antimicrobial properties. Titanium dioxide nanoparticles (TiO2) were co-sensitized with 5-methylphenazinium methosulfate (PMS) and carboxy-functionalized cadmium telluride quantum dots (CdTe QDs), and immobilized on a fluorine-doped tin oxide electrode. The surface morphology and electrochemical properties of the modified electrode were investigated by scanning electron microscopy and amperometry, respectively. A composite consisting of TiO2, PMS and CdTe QDs in a nafion film has a response to TA under LED light higher than that observed for each separate component. Under optimized experimental conditions and at an applied voltage of +0.4 V vs Ag/AgCl, the photoelectrochemical sensor has a linear response in the 0.2 to 200 μmol L−1 TA concentration range and a detection limit of 60 nmol L−1. The sensor was successfully applied to the determination of TA in spiked extracts from three medicinal plants, with recovery values between 98.3 and 103.9 %.Schematic diagram for photoelectrochemical detection of tannic acid based on a fluorine doped tin oxide electrode modified with titanium oxide, 5-methylphenazinium methosulfate and carboxy-functionalized cadmium telluride quantum dots [ABSTRACT FROM AUTHOR]