light spectrum
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2024 ◽  
Vol 84 ◽  
Author(s):  
M. C. S. Virtuoso ◽  
E. H. C. Silva ◽  
E. M. Silva ◽  
T. S. Valente ◽  
P. F. Vargas ◽  
...  

Abstract The in vitro sporulation of Didymella bryoniae is of great importance for studies that require pure inoculum and in large quantities. Thus, the objectives of this study were to identify the best condition for D. bryoniae sporulation combining different light spectra (UV-A or UV-B light, white light, and continuous dark), with distinct culture media (PDA, V8, ML, and PDAB) and, to evaluate fungus’ survivability stored at -20°C over time. The fungus samples were only able to sporulate when subjected to the UV-B light treatment, regardless of the culture medium. The highest appearance of spores conidium type was observed in the PDAB medium, and the lowest production occurred in the ML medium. Reproductive structures, such as perithecia and pycnidia, were observed in all culture media. However, there was considerable variation in the amount of each structure between the different culture media. The ML and V8 media showed a greater number of perithecia and the PDA and PDAB media presented a greater proportion of pycnidia compared to perithecia. The storage duration at -20°C did not affect mycelial growth or mycelial growth rate. In conclusion, the UV-B light is essential for D. bryoniae in vitro sporulation. Moreover, the culture medium composition influences the type of fungal structure produced, as well as spores’ size and quantity. Freezing at -20°C is an efficient technique that can be used to store D. bryoniae for at least five months without loss of viability.


2022 ◽  
Author(s):  
Ting-Kai Leung ◽  
Chia-Wei Li ◽  
Yu-Chun Lo ◽  
Ping-Yen Tsai ◽  
Jia-Yi Wang

Abstract There is still no clear explanation of the process of perceptual consciousness that connects our body with brain. Innovation on the technology of bioceramic has now advanced towards clinical applications, including rehabilitation of brain infarction, therapies of insomnia and migraine. To demonstrate how ‘resonant energy transfer through the bioceramic material with tempo sound and visible light spectrum’ (bioceramic material stimulation, BMS) non-invasively affects perceptual consciousness, we investigated the responses of participants to BMS on perceptual consciousness by questionnaire of subjective descriptions and analyzed resting state fMRI during BMS. There were 61.3% participants who were categorized as positive group with various types of perceptual consciousness. By setting a threshold value at ‘p<0.001’, enhanced connections of ‘parahippocampal gyrus to cerebellar lobule V’ and ‘angular gyrus to precuneus’ were found. However, decreased connection of ‘caudate nucleus to cerebellar lobule VIIb’ was found. We conclude that the most affected brain functions by BMS including somatosensory, audio-visual perception and social cognition. The analysis of functional connectivity during BMS may help us gain more knowledge of consciousness and related division of neuroscience in humans.


2022 ◽  
Vol 21 (1) ◽  
pp. 11-21
Author(s):  
Bambang Kusmayadi Gunawan ◽  
Kukuh Nirmala ◽  
Dinar Tri Soelistyowati ◽  
Daniel Djokosetiyanto ◽  
Wildan Nurussalam

This study aimed to evaluate the effect of light spectrum on growth and color performance of giant giant gourami Padang strain. The experiment used a completely randomized design (RAL) with four light emitting diode (LED) treatments in  different emission spectra (white, red, green, and blue) at 550 Lux intensity, compared to the control treatment (light room with white tubular lamp at 50 Lux intensity). The irradiation was carried out for 12 hours of photoperiod. The fish used had the total length of 82.90±4.2 mm and body weight of 9.87 ± 0.99 g. The highest growth performance was found in blue LED treatment with the specific growth rate of  2.73 ± 0.2% and feed efficiency of 86.26 ± 2.71%. The best color performance was found in red LED treatment with the RGB ratio of 44.57 ± 0.62% in dorsal fin, 38.41 ± 1.36% in pectoral fins, and 45.33 ± 2.25% in anal fin with the chromatophore cell concentration at 1.973±58 cells/mm2.   Keywords : Osphronemus gouramy, blue LED, spectrum, chromatophore, light   ABSTRAK   Penelitian ini bertujuan untuk mengevaluasi pengaruh spektrum cahaya terhadap kinerja pertumbuhan dan warna ikan gurami strain Padang. Rancangan penelitian yang digunakan adalah rancangan acak lengkap (RAL) dengan 4 perlakuan cahaya lampu light emitting diodes (LED)  yang memiliki spektrum panjang gelombang berbeda (putih, merah, hijau dan biru) intensitas 550 Lux dan kontrol (cahaya ruang berasal dari lampu tubular putih intensitas 50 Lux). Penyinaran dilakukan selama 12 jam mengikuti fotoperiod. Ikan uji yang digunakan memiliki panjang total 82,90 ± 4,2 mm, dengan bobot 9,87 ± 0,99 g. Kinerja pertumbuhan terbaik terdapat pada perlakuan LED biru dengan laju pertumbuhan spesifik sebesar 2,73 ± 0,2% dan efisiensi pakan sebesar 86,26 ± 2,71%. Performa warna terbaik terdapat pada perlakuan LED merah dengan rasio warna merah pada RGB bagian dorsal sebesar 44,57 ± 0,62%, sirip pektoral sebesar 38,41 ± 1,36%, dan sirip anal sebesar 45,33 ±  2,25% dengan jumlah sel kromatofor sebanyak 1973 sel/mm2.   Kata kunci : Osphronemus gouramy, LED biru, spektrum, kromatofor, cahaya        


2022 ◽  
Vol 12 (1) ◽  
Author(s):  
Panita Chutimanukul ◽  
Praderm Wanichananan ◽  
Supattana Janta ◽  
Theerayut Toojinda ◽  
Clive Terence Darwell ◽  
...  

AbstractLight-emitting diodes (LEDs) are an artificial light source used in indoor cultivation to influence plant growth, photosynthesis performance and secondary metabolite synthesis. Holy basil plants (Ocimum tenuiflorum) were cultivated under fully controlled environmental conditions with different red (R) and blue (B) light intensity ratios (3R:1B, 1R:1B and 1R:3B), along with combined green (G) LED (2R:1G:2B). The photosynthetic activities of both cultivars were maximal under 3R:1B. However, the highest fresh (FW) and dry (DW) weight values of green holy basil were recorded under 3R:1B and 2R:1G:2B, significantly higher than those under alternative light conditions. For red holy basil, the highest FW and DW were recorded under 1R:3B. Moreover, 2R:1G:2B treatment promoted pigment (chlorophyll and carotenoid) accumulation in green holy basil, while red holy basil was found to be rich in both pigments under 3R:1B. Antioxidant capacity was also influenced by light spectrum, resulting in greater total phenolic content (TPC) and DPPH accumulation in both cultivars under 1R:3B. The highest content of flavonoid in green holy basil was detected under 1R:1B; meanwhile, 1R:3B treatment significantly promoted flavonoid content in red holy basil. In addition, anthocyanin content increased in red holy basil under 1R:3B conditions. Gas chromatography coupled with mass spectrometry (GC–MS/MS) analysis of chemical composition showed higher proportional accumulation in Methyleugenol and Caryophyllene of two cultivars grown under all light spectrum ratios at two developmental stages. Overall, specific light spectrum ratios induced different chemical composition responses in each cultivar and at each developmental stage. These results suggest that 3R:1B was favorable for biomass accumulation and photosynthetic responses in green holy basil, while 1R:3B provided antioxidant accumulation. For red holy basil cultivation, 1R:3B provided optimal growing conditions, promoting improvements in plant biomass, and physiological and antioxidant capacities.


Plants ◽  
2022 ◽  
Vol 11 (2) ◽  
pp. 176
Author(s):  
Tatjana G. Shibaeva ◽  
Elena G. Sherudilo ◽  
Alexandra A. Rubaeva ◽  
Alexander F. Titov

The effect of continuous lighting (CL, 24 h) and light spectrum on growth and nutritional quality of arugula (Eruca sativa), broccoli (Brassica oleracea var. italic), mizuna (Brassica rapa. var. nipposinica), and radish (Raphanus sativus var. radicula) were investigated in growth chambers under light-emitting diode (LED) and fluorescent lighting. Microgreens were grown under four combinations of two photoperiods (16 h and 24 h) providing daily light integral (DLI) of 15.6 and 23.3 mol m−2 day−1, correspondingly) with two light spectra: LED lamps and fluorescent lamps (FLU). The results show that fresh and dry weights as well as leaf mass per area and robust index of harvested arugula, broccoli, mizuna, and radish seedlings were significantly higher under CL compared to 16 h photoperiod regardless of light quality. There were no visible signs of leaf photodamage. In all CL-treated plants higher chlorophyll a/b and carotenoid-to-chlorophyll ratios were observed in all plants except mizuna. CL treatment was beneficial for anthocyanin, flavonoid, and proline accumulation. Higher activities of antioxidant enzymes (catalase, superoxide dismutase, ascorbate peroxidase, and guaiacol peroxidase) were also observed in CL-treated plants. In most cases, the effects were more pronounced under LED lighting. These results indicate that plants under mild oxidative stress induced by CL accumulated more non-enzymatic antioxidants and increased the activities of antioxidant enzymes. This added nutritional value to microgreens that are used as functional foods providing health benefits. We suggest that for arugula, broccoli, mizuna, and radish, an LED CL production strategy is possible and can have economic and nutritional benefits.


2022 ◽  
Vol 15 ◽  
Author(s):  
Laura C. E. Steel ◽  
Selma Tir ◽  
Shu K. E. Tam ◽  
James N. Bussell ◽  
Manuel Spitschan ◽  
...  

Light is known to exert powerful effects on behavior and physiology, including upon the amount and distribution of activity across the day/night cycle. Here we use home cage activity monitoring to measure the effect of differences in home cage light spectrum and intensity on key circadian activity parameters in mice. Due to the relative positioning of any individually ventilated cage (IVC) with regard to the animal facility lighting, notable differences in light intensity occur across the IVC rack. Although all mice were found to be entrained, significant differences in the timing of activity onset and differences in activity levels were found between mice housed in standard versus red filtering cages. Furthermore, by calculating the effective irradiance based upon the known mouse photopigments, a significant relationship between light intensity and key circadian parameters are shown. Perhaps unsurprisingly given the important role of the circadian photopigment melanopsin in circadian entrainment, melanopic illuminance is shown to correlate more strongly with key circadian activity parameters than photopic lux. Collectively, our results suggest that differences in light intensity may reflect an uncharacterized source of variation in laboratory rodent research, with potential consequences for reproducibility. Room design and layout vary within and between facilities, and caging design and lighting location relative to cage position can be highly variable. We suggest that cage position should be factored into experimental design, and wherever possible, experimental lighting conditions should be characterized as a way of accounting for this source of variation.


2022 ◽  
Vol 11 (1) ◽  
Author(s):  
Mani Teja Vijjapu ◽  
Mohammed E. Fouda ◽  
Agamyrat Agambayev ◽  
Chun Hong Kang ◽  
Chun-Ho Lin ◽  
...  

AbstractNeuromorphic vision sensors have been extremely beneficial in developing energy-efficient intelligent systems for robotics and privacy-preserving security applications. There is a dire need for devices to mimic the retina’s photoreceptors that encode the light illumination into a sequence of spikes to develop such sensors. Herein, we develop a hybrid perovskite-based flexible photoreceptor whose capacitance changes proportionally to the light intensity mimicking the retina’s rod cells, paving the way for developing an efficient artificial retina network. The proposed device constitutes a hybrid nanocomposite of perovskites (methyl-ammonium lead bromide) and the ferroelectric terpolymer (polyvinylidene fluoride trifluoroethylene-chlorofluoroethylene). A metal-insulator-metal type capacitor with the prepared composite exhibits the unique and photosensitive capacitive behavior at various light intensities in the visible light spectrum. The proposed photoreceptor mimics the spectral sensitivity curve of human photopic vision. The hybrid nanocomposite is stable in ambient air for 129 weeks, with no observable degradation of the composite due to the encapsulation of hybrid perovskites in the hydrophobic polymer. The functionality of the proposed photoreceptor to recognize handwritten digits (MNIST) dataset using an unsupervised trained spiking neural network with 72.05% recognition accuracy is demonstrated. This demonstration proves the potential of the proposed sensor for neuromorphic vision applications.


Author(s):  
Hugo Rene Lárraga-Altamirano ◽  
Dalia Rosario Hernández-López ◽  
Ana María Piedad-Rubio ◽  
Jesús Antonio Amador-Soni

This research work shows that with the use of remote sensing technology it is possible to more effectively fulfill two of the purposes pursued by farmers in the field; manage crops more efficiently and include environmental care in decision-making. Specifically, remote sensing is applied in the context of precision agriculture through geographic information systems (GIS), unmanned aerial vehicles (UAV), multispectral sensors that capture the reflectance of the infrared band of the light spectrum (for interpretation of the biochemical state of the crop), global geopositioning systems (GPS), among others. This study limits the use of this technology to the processing of multispectral images obtained by aerial photogrammetry, and its subsequent treatment for the generation of orthoimages, the calculation of the NDVI vegetation index and the classification of land cover by clustering. Finally, the effect of classification with RGB and multispectral images is analyzed.


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