scholarly journals Red Light Exposure Delays Appearance and Aroma Deterioration of Fresh-Cut Watermelon during Retail Display

2020 ◽  
Vol 2020 ◽  
pp. 1-9
Author(s):  
Yue Shi ◽  
Yubin Wang ◽  
Yue Ma ◽  
Yong Xu ◽  
Xiaoyan Zhao ◽  
...  
Keyword(s):  
Weight Loss ◽  
White Light ◽  
Light Exposure ◽  
Red Light ◽  
Microbial Metabolism ◽  
Color Difference ◽  
The Self ◽  
Retail Display ◽  
Fresh Cut ◽  
Fruit Surface

Appearance and aroma deterioration are the main concerns during the retail display of fresh-cut watermelons. Here, fresh-cut watermelons were exposed to the red, green, blue, and conventional white light at 4°C for 4 days, respectively, and their resulting qualities were compared with the conventional white light as the control. Specifically, the red light presented its maximum emissions in 620–650 nm with a purity of 100% and an intensity of 1104.7 lux. The red light exposure reduced the weight loss to 1.81%, which was reduced by 51.1% of the control. The red light exposure reduced the color difference of the fruit surface significantly as well as maintaining its redness. The water-soaking ratio of the red light exposure was also reduced by 62.8% of the control. Moreover, the red light exposure delayed the aroma deterioration, which resulted from both microbial metabolism and the self-metabolism of volatiles of the fresh-cut watermelon. In summary, the red light exposure was better to delay the appearance and aroma deterioration of fresh-cut watermelons than the conventional white light during their retail display.

Photoinduced changes in amorphous selenium

2014 ◽  
Vol 92 (7/8) ◽  
pp. 663-666 ◽  
Author(s):  
F. Djefaflia ◽  
C. Mebarkia ◽  
A. Hafdallah ◽  
M.L. Benkhedir ◽  
A. Belfedal
Keyword(s):  
Thin Films ◽  
White Light ◽  
Room Temperature ◽  
Light Exposure ◽  
Red Light ◽  
Amorphous Selenium ◽  
Corning Glass ◽  
Visible Transmittance ◽  
Photoinduced Changes ◽  
Photoinduced Phenomena

Photoinduced phenomena in thin films of amorphous selenium (a-Se) have been a subject of intensive researches so far. Thin films of a-Se were deposited on corning glass by thermal evaporation, with several thicknesses. The influence of light exposure, with different colors (blue or red or natural white light), on the optical and structural properties of a-Se thin films was carried out by using ultraviolet–visible transmittance spectroscopy. It was found that the gap of the samples illuminated with blue and natural white light at room temperature shifts to lower energies. This photodarkening is stable at room temperature and is irreversible even after several days. On the other hand the photodarkening in the samples illuminated with red light is much smaller than that for samples illuminated with blue and natural white light. The photodarkening is accompanied by an increase in the refractive index. These results are discussed with results, previously obtained, about the photoinduced changes of the negative-U centers in, T– and T+, studied using time-of-flight (TOF) traces recorded on samples prepared in the same conditions. These TOF measurements show that the defect level T– at 0.4 eV above the valence band edge shifts to 0.5 eV under illumination with white light at room temperature. This effect is not seen if the illumination is done at 35 °C. These phenomena are attributed to nanocrystallization in the a-Se films.

scholarly journals Different Postharvest Responses of Fresh-Cut Sweet Peppers Related to Quality and Antioxidant and Phenylalanine Ammonia Lyase Activities during Exposure to Light-Emitting Diode Treatments

Foods ◽  
2019 ◽  
Vol 8 (9) ◽  
pp. 359 ◽  
Author(s):  
Gludia M. Maroga ◽  
Puffy Soundy ◽  
Dharini Sivakumar
Keyword(s):  
Weight Loss ◽  
Phenylalanine Ammonia Lyase ◽  
Light Emitting Diode ◽  
Ascorbic Acid Content ◽  
Color Difference ◽  
Sweet Pepper ◽  
Blue Led ◽  
Led Light ◽  
Red Led ◽  
Fresh Cut

The influence of emitting diode (LED) treatments for 8 h per day on functional quality of three types of fresh-cut sweet peppers (yellow, red, and green) were investigated after 3, 7, 11, and 14 days postharvest storage on the market shelf at 7 °C. Red LED light (660 nm, 150 μmol m−2 s−1) reduced weight loss to commercially acceptable level levels (≤2.0%) in fresh-cuts of yellow and green sweet peppers at 7 and 11 d, respectively. Blue LED light (450 nm, 100 μmol m−2 s−1) maintained weight loss acceptable for marketing in red fresh-cut sweet peppers up to 11 d. Highest marketability with minimum changes in color difference (∆E) and functional compounds (total phenols, ascorbic acid content, and antioxidant activity) were obtained in yellow and green sweet pepper fresh-cuts exposed to red LED light up to 7 and 11 d, respectively, and for red sweet pepper fresh-cuts exposed to blue LED light for 11 d. Red LED light maintained the highest concentrations of β carotene, chlorophyll, and lycopene in yellow, green, and red sweet pepper fresh-cuts up to 7 d. Similarly, blue LED light showed the highest increase in lycopene concentrations for red sweet pepper fresh-cuts up to 7 d. Red LED (yellow and green sweet peppers) and blue LED (red sweet pepper) lights maintained phenolic compounds by increasing phenylalanine ammonia lyase activity. Thus, the results indicate a new approach to improve functional compounds of different types of fresh-cut sweet pepper.

scholarly journals PERTUMBUHAN PARUH ANAK ITIK MAGELANG (Anas javanica) AKIBAT INDUK YANG DISUPLEMENTASI KURKUMIN (Curcuma longa L.) DAN DIPAJAN CAHAYA MERAH

2018 ◽  
Vol 7 (1) ◽  
Author(s):  
Luthfiana Ulil Albab ◽  
Sri Isdadiyanto ◽  
Muhammad Anwar Djaelani
Keyword(s):  
White Light ◽  
Egg Production ◽  
Light Exposure ◽  
Curcuma Longa ◽  
Red Light ◽  
Meat Production ◽  
Parametric Test ◽  
Wild Duck ◽  
Randomized Design ◽  
Length Width

ABSTRACTMagelang duck is the Indonesian wild duck that have high egg and meat production. To increase egg production hence in this research magelang ducks are supplemented with curcumin and exposure of white and red light.  The aim of the research to study growth beak duckling from parental magelang ducks that supplemented curcumin and red light exposure. The research design used  complete randomized design from fourdifferents group of ducks, i.e., A0B0 (duck without curcumin and white light exposure), A0B1 (duck without curcumin and red light exposure), A0B1 (curcumin dose of 18 mg/duck/day and white light exposure and A1B1 (curcumin dose 18 mg/duck/day and red light exposure). Five female ducklings were taken from each group and their morphometry were measured. The variables of this research were the length, width and height of beaks. The collected data were analized with Kruskal-Wallis non parametric test and would be further tested with Mann-Whitney-U test. The result of this research showed that curcumin supplementaion and red light exposure in ducks affected the magelang ducklings beak growth. Keywords : beaks, curcumin, growth, magelang ducks, red light. ABSTRAKItik magelang merupakan itik liar asli Indonesia yang memiliki produksi telur dan daging relatif tinggi. Untuk meningkatkan produksi telur maka pada penelitian ini itik magelang diberi suplementasi kurkumin serta pajanan cahaya putih dan merah. Penelitian ini bertujuan untuk mengkaji pengaruh pemberian kurkumin serta cahaya putih dan merah pada induk terhadap pertumbuhan paruh anak itik magelang. Rancangan penelitian yang digunakan adalah Rancangan Acak Lengkap (RAL) yang berasal dari empat induk yang berbeda, yaitu induk A0B0 (tanpa diberi kurkumin dan dipapar cahaya putih),  A0B1 (tanpa diberi kurkumin dan  dipapar cahaya merah), A1B0 (dosis kurkumin 18 mg/ekor/hari dan paparan cahaya putih) dan A1B1 (dosis kurkumin 18 mg/ekor/hari pada cahaya merah). Masing-masing kelompok induk diambil lima ekor anak itik untuk diukur paruhnya. Variabel yang diamati berupa pengukuran panjang, lebar, dan tebal paruh. Data yang diperoleh dianalisis menggunakan uji non parametrik Kruskal-Wallis dan diuji lanjut menggunakan uji Mann-Whitney-U. Hasil penelitian ini menunjukkan bahwa suplementasi kurkumin dan pajanan cahaya putih serta merah pada induk secara umum dapat meningkatkan pertumbuhan paruh anak itik. Kata kunci: paruh, kurkumin, pertumbuhan, itik magelang, cahaya merah.

Light at Night and Measures of Alertness and Performance

2015 ◽  
Vol 18 (1) ◽  
pp. 90-100 ◽  
Author(s):  
Mariana G. Figueiro ◽  
Levent Sahin ◽  
Brittany Wood ◽  
Barbara Plitnick
Keyword(s):  
White Light ◽  
Light Exposure ◽  
Red Light ◽  
Reaction Times ◽  
Light At Night ◽  
Improve Performance ◽  
Practical Applications ◽  
Circadian Phase ◽  
Dim Light ◽  
And Performance

Rotating-shift workers, particularly those working at night, are likely to experience sleepiness, decreased productivity, and impaired safety while on the job. Light at night has been shown to have acute alerting effects, reduce sleepiness, and improve performance. However, light at night can also suppress melatonin and induce circadian disruption, both of which have been linked to increased health risks. Previous studies have shown that long-wavelength (red) light exposure increases objective and subjective measures of alertness at night, without suppressing nocturnal melatonin. This study investigated whether exposure to red light at night would not only increase measures of alertness but also improve performance. It was hypothesized that exposure to both red (630 nm) and white (2,568 K) lights would improve performance but that only white light would significantly affect melatonin levels. Seventeen individuals participated in a 3-week, within-subjects, nighttime laboratory study. Compared to remaining in dim light, participants had significantly faster reaction times in the GO/NOGO test after exposure to both red light and white light. Compared to dim light exposure, power in the alpha and alpha-theta regions was significantly decreased after exposure to red light. Melatonin levels were significantly suppressed by white light only. Results show that not only can red light improve measures of alertness, but it can also improve certain types of performance at night without affecting melatonin levels. These findings could have significant practical applications for nurses; red light could help nurses working rotating shifts maintain nighttime alertness, without suppressing melatonin or changing their circadian phase.

scholarly journals Artificial complementary chromatic acclimation gene expression system in Escherichia coli

2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Dwi Ariyanti ◽  
Kazunori Ikebukuro ◽  
Koji Sode
Keyword(s):  
Gene Expression ◽  
Escherichia Coli ◽  
Light Exposure ◽  
Expression System ◽  
Red Light ◽  
Green Light ◽  
Light Illumination ◽  
Multiple Gene ◽  
Gene Expression System ◽  
Chromatic Acclimation

Abstract Background The development of multiple gene expression systems, especially those based on the physical signals, such as multiple color light irradiations, is challenging. Complementary chromatic acclimation (CCA), a photoreversible process that facilitates the control of cellular expression using light of different wavelengths in cyanobacteria, is one example. In this study, an artificial CCA systems, inspired by type III CCA light-regulated gene expression, was designed by employing a single photosensor system, the CcaS/CcaR green light gene expression system derived from Synechocystis sp. PCC6803, combined with G-box (the regulator recognized by activated CcaR), the cognate cpcG2 promoter, and the constitutively transcribed promoter, the PtrcΔLacO promoter. Results One G-box was inserted upstream of the cpcG2 promoter and a reporter gene, the rfp gene (green light-induced gene expression), and the other G-box was inserted between the PtrcΔLacO promoter and a reporter gene, the bfp gene (red light-induced gene expression). The Escherichia coli transformants with plasmid-encoded genes were evaluated at the transcriptional and translational levels under red or green light illumination. Under green light illumination, the transcription and translation of the rfp gene were observed, whereas the expression of the bfp gene was repressed. Under red light illumination, the transcription and translation of the bfp gene were observed, whereas the expression of the rfp gene was repressed. During the red and green light exposure cycles at every 6 h, BFP expression increased under red light exposure while RFP expression was repressed, and RFP expression increased under green light exposure while BFP expression was repressed. Conclusion An artificial CCA system was developed to realize a multiple gene expression system, which was regulated by two colors, red and green lights, using a single photosensor system, the CcaS/CcaR system derived from Synechocystis sp. PCC6803, in E. coli. The artificial CCA system functioned repeatedly during red and green light exposure cycles. These results demonstrate the potential application of this CCA gene expression system for the production of multiple metabolites in a variety of microorganisms, such as cyanobacteria.

scholarly journals The Preferences of Different Cultivars of Lettuce Seedlings (Lactuca sativa L.) for the Spectral Composition of Light

Agronomy ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1211
Author(s):  
Barbara Frąszczak ◽  
Monika Kula-Maximenko
Keyword(s):  
Chlorophyll Content ◽  
Blue Light ◽  
White Light ◽  
Leaf Shape ◽  
Red Light ◽  
Spectral Composition ◽  
Fresh Weight ◽  
Light Spectrum ◽  
Dark Green ◽  
Relative Chlorophyll Content

The spectrum of light significantly influences the growth of plants cultivated in closed systems. Five lettuce cultivars with different leaf colours were grown under white light (W, 170 μmol m−2 s−1) and under white light with the addition of red (W + R) or blue light (W + B) (230 μmol m−2 s−1). The plants were grown until they reached the seedling phase (30 days). Each cultivar reacted differently to the light spectrum applied. The red-leaved cultivar exhibited the strongest plasticity in response to the spectrum. The blue light stimulated the growth of the leaf surface in all the plants. The red light negatively influenced the length of leaves in the cultivars, but it positively affected their number in red and dark-green lettuce. It also increased the relative chlorophyll content and fresh weight gain in the cultivars containing anthocyanins. When the cultivars were grown under white light, they had longer leaves and higher value of the leaf shape index. The light-green cultivars had a greater fresh weight. Both the addition of blue and red light significantly increased the relative chlorophyll content in the dark-green cultivar. The spectrum enhanced with blue light had positive influence on most of the parameters under analysis in butter lettuce cultivars. These cultivars were also characterised by the highest absorbance of blue light.

Use of A GAS Jet Technique to Prepare Microcrystalline Silicon Based Solar Cells at High I-Layer Deposition Rates

1999 ◽  
Vol 557 ◽  
Author(s):  
S.J. Jones ◽  
R. Crucet ◽  
X. Deng ◽  
J. Doehler ◽  
R. Kopf ◽  
...  
Keyword(s):  
Solar Cells ◽  
Peak Power ◽  
Light Exposure ◽  
Red Light ◽  
Gas Jet ◽  
Scale Production ◽  
Microcrystalline Silicon ◽  
Deposition Rates ◽  
Layer Deposition ◽  
Power Outputs

AbstractUsing a Gas Jet thin film deposition technique, microcrystalline silicon (μc-Si) materials were prepared at rates as high as 15-20 Å/s. The technique involves the use of a gas jet flow that is subjected to a high intensity microwave source. The quality of the material has been optimized through the variation of a number of deposition conditions including the substrate temperature, the gas flows, and the applied microwave power. The best films were made using deposition rates near 16 Å/s. These materials have been used as i-layers for red light absorbing, nip single-junction solar cells. Using a 610nm cutoff filter which only allows red light to strike the device, pre-light soaked currents as high as 10 mA/cm2 and 2.2-2.3% red-light pre-light soaked peak power outputs have been obtained for cells with i-layer thicknesses near 1 micron. This compares with currents of 10-11 mA/cm2 and 4% initial red-light peak power outputs obtained for high efficiency amorphous silicon germanium alloy (a-SiGe:H) devices. The AM1.5 white light efficiencies for these microcrystalline cells are 5.9-6.0%. While the efficiencies for the a-SiGe:H cells degrade by 15-20% after long term light exposure, the efficiencies for the microcrystalline cells before and after prolonged light exposure are similar, within measurement error. Considering these results, the Gas Jet deposition method is a promising technique for the deposition of μc-Si solar cells due to the ability to achieve reasonable stable efficiencies for cells at i-layer deposition rates (16 Å/s) which make large-scale production economically feasible.

Effects of electron-withdrawing groups in imidazole-phenanthroline ligands and their influence on the photophysical properties of EuIII complexes for white light-emitting diodes

2017 ◽  
Vol 41 (18) ◽  
pp. 9826-9839 ◽  
Author(s):  
Boddula Rajamouli ◽  
Rachna Devi ◽  
Abhijeet Mohanty ◽  
Venkata Krishnan ◽  
Sivakumar Vaidyanathan
Keyword(s):  
Thin Film ◽  
Quantum Yield ◽  
White Light ◽  
Light Emitting Diode ◽  
Photophysical Properties ◽  
Red Light ◽  
Europium Complexes ◽  
Light Emitting ◽  
White Light Emitting Diodes ◽  
Phenanthroline Ligands

The red light emitting diode (LED) was fabricated by using europium complexes with InGaN LED (395 nm) and shown digital images, corresponding CIE color coordinates (red region) as well as obtained highest quantum yield of the thin film (78.7%).

(K0.5Na0.5)NbO3:Eu3+/Bi3+: a novel, highly efficient, red light-emitting material with superior water resistance behavior

RSC Advances ◽  
2015 ◽  
Vol 5 (6) ◽  
pp. 4707-4715 ◽  
Author(s):  
Qiwei Zhang ◽  
Haiqin Sun ◽  
Tao Kuang ◽  
Ruiguang Xing ◽  
Xihong Hao
Keyword(s):  
Blue Light ◽  
White Light ◽  
High Performance ◽  
Water Resistance ◽  
Light Emitting Diodes ◽  
Red Light ◽  
Light Emitting ◽  
Highly Efficient ◽  
White Light Emitting Diodes

Materials emitting red light (∼611 nm) under excitation with blue light (440–470 nm) are highly desired for fabricating high-performance white light-emitting diodes (LEDs).

Pineal response types in the frog's brain under white light exposure

1979 ◽  
Vol 36 (1) ◽  
Author(s):  
J. Cadusseau ◽  
F. Gaillard ◽  
G. Galand
Keyword(s):  
White Light ◽  
Light Exposure
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