Tubular Daylighting Devices and People: A comparison of the human responses to Tubular Daylighting Devices and fluorescent lighting

<p>Tubular Daylighting Devices are used to bring daylight into deep-plan spaces, and meet sustainability goals. However, they are expensive, and justification for their use lies in hypothesised benefits they can provide in areas such as well-being and productivity. Yet, there is very little research into the effects of Tubular Daylighting Devices. The broader daylighting literature suggests that benefits to satisfaction, mood, and performance are possible — though research into the benefits of daylight is still not conclusive. Therefore, a before and after study was carried out in a windowless computer room in the university to compare how the students responded under TDDs versus typical electric lighting. Their cognitive performance, change in mood, average sleepiness, and perceptions of the room and lighting were measured. TDDs significantly increased ratings of room attractiveness and brightness, and had no more perceived glare than the electric lighting. Ratings of lighting quality were on a par with both typical electric lighting and good modern lighting. They were also just as effective on overcast days as sunny. No effects were found on performance or sleepiness, and mood results were inconclusive. Overall, it is suggested that TDDs can be considered to be on a par with good modern lighting, and superior to typical existing lighting. Note, however, that it is possible that effects in rooms with windows could differ from those found here. Further research should use longer exposures and larger sample sizes if they wish to find performance effects.</p>

Tubular Daylighting Devices and People: A comparison of the human responses to Tubular Daylighting Devices and fluorescent lighting

<p>Tubular Daylighting Devices are used to bring daylight into deep-plan spaces, and meet sustainability goals. However, they are expensive, and justification for their use lies in hypothesised benefits they can provide in areas such as well-being and productivity. Yet, there is very little research into the effects of Tubular Daylighting Devices. The broader daylighting literature suggests that benefits to satisfaction, mood, and performance are possible — though research into the benefits of daylight is still not conclusive. Therefore, a before and after study was carried out in a windowless computer room in the university to compare how the students responded under TDDs versus typical electric lighting. Their cognitive performance, change in mood, average sleepiness, and perceptions of the room and lighting were measured. TDDs significantly increased ratings of room attractiveness and brightness, and had no more perceived glare than the electric lighting. Ratings of lighting quality were on a par with both typical electric lighting and good modern lighting. They were also just as effective on overcast days as sunny. No effects were found on performance or sleepiness, and mood results were inconclusive. Overall, it is suggested that TDDs can be considered to be on a par with good modern lighting, and superior to typical existing lighting. Note, however, that it is possible that effects in rooms with windows could differ from those found here. Further research should use longer exposures and larger sample sizes if they wish to find performance effects.</p>

Tubular Daylighting Devices and People: A comparison of the human responses to Tubular Daylighting Devices and fluorescent lighting

<p>Tubular Daylighting Devices are used to bring daylight into deep-plan spaces, and meet sustainability goals. However, they are expensive, and justification for their use lies in hypothesised benefits they can provide in areas such as well-being and productivity. Yet, there is very little research into the effects of Tubular Daylighting Devices. The broader daylighting literature suggests that benefits to satisfaction, mood, and performance are possible — though research into the benefits of daylight is still not conclusive. Therefore, a before and after study was carried out in a windowless computer room in the university to compare how the students responded under TDDs versus typical electric lighting. Their cognitive performance, change in mood, average sleepiness, and perceptions of the room and lighting were measured. TDDs significantly increased ratings of room attractiveness and brightness, and had no more perceived glare than the electric lighting. Ratings of lighting quality were on a par with both typical electric lighting and good modern lighting. They were also just as effective on overcast days as sunny. No effects were found on performance or sleepiness, and mood results were inconclusive. Overall, it is suggested that TDDs can be considered to be on a par with good modern lighting, and superior to typical existing lighting. Note, however, that it is possible that effects in rooms with windows could differ from those found here. Further research should use longer exposures and larger sample sizes if they wish to find performance effects.</p>

Tubular Daylighting Devices and People: A comparison of the human responses to Tubular Daylighting Devices and fluorescent lighting

<p>Tubular Daylighting Devices are used to bring daylight into deep-plan spaces, and meet sustainability goals. However, they are expensive, and justification for their use lies in hypothesised benefits they can provide in areas such as well-being and productivity. Yet, there is very little research into the effects of Tubular Daylighting Devices. The broader daylighting literature suggests that benefits to satisfaction, mood, and performance are possible — though research into the benefits of daylight is still not conclusive. Therefore, a before and after study was carried out in a windowless computer room in the university to compare how the students responded under TDDs versus typical electric lighting. Their cognitive performance, change in mood, average sleepiness, and perceptions of the room and lighting were measured. TDDs significantly increased ratings of room attractiveness and brightness, and had no more perceived glare than the electric lighting. Ratings of lighting quality were on a par with both typical electric lighting and good modern lighting. They were also just as effective on overcast days as sunny. No effects were found on performance or sleepiness, and mood results were inconclusive. Overall, it is suggested that TDDs can be considered to be on a par with good modern lighting, and superior to typical existing lighting. Note, however, that it is possible that effects in rooms with windows could differ from those found here. Further research should use longer exposures and larger sample sizes if they wish to find performance effects.</p>

Performance analysis of standalone photovoltaic power generation in different load conditions in India

The conversion of solar energy into electrical energy by the design of energy-efficient way is the key objective of this paper, which can be used as a main source of power for the main building of Polytechnic Institute to meet its daily energy requirement by replacing the all exist-ing fluorescent lighting loads to LEDs. The main purpose to choose a standalone photovoltaic system is due to the huge power cut in this location. This institute is situated in a rural area of West Bengal, India. The use of photovoltaic power relies upon assortment factors, such as structuring, topographical area, climate condition, sun-based irradiance, and burden utilization. Point by point use examinations including the two sorts of lighting burden, establishment, and upkeep of sun-based PV framework amid its life expectancy has been completed. Moreover, the analysis has two dimensions, one is cost comparison and payback calculation with respect to energy by replacement of load and another is, though the initial investment is high in a off-grid photovoltaic system, during the life span of the scheme, it not only returns this capital in-vestment but also gains substantial dividend.

Microgreens: Functional Food with Antiproliferative Cancer Properties Influenced by Light

The anti-proliferative/pro-oxidant efficacy of green pea, soybean, radish, Red Rambo radish, and rocket microgreens, cultivated under either fluorescent lighting (predominant spectral peaks in green and orange) or combination light-emitting diode (LED, predominant spectral peak in blue) was investigated using Ewing sarcoma lines, RD-ES and A673, respectively. All aqueous microgreen extracts significantly reduced cell proliferation (cancer prevention effect) to varying extents in two-dimensional sarcoma cell cultures. The effect of the polyphenol fraction in the aqueous food matrix was unrelated to total polyphenol content, which differed between species and light treatment. Only Pisum sativum (LED-grown) extracts exercised anti-proliferative and pro-apoptotic effects in both three-dimensional RD-ES and A673 spheroids (early tumor progression prevention), without cytotoxic effects on healthy L929 fibroblasts. A similar anti-tumor effect of Red Rambo radish (LED and fluorescent-grown) was evident only in the RD-ES spheroids. Aside from the promising anti-tumor potential of the polyphenol fraction of green pea microgreens, the latter also displayed favorable growth quality parameters, along with radish, under both light treatments over the 10 day cultivation period.

256 Spectrophotometric Properties of 31 Different Commercially Available Blue Blocking Glasses Under Electric Room Lighting

Introduction Blue blocking glasses are often marketed to promote relaxation, sleep, and circadian health by attenuating melatonin-suppressing light exposure. But these glasses represent a wide range of tint and other lens properties. Further, the utility of these glasses under ecologically valid indoor conditions (where light is typically generated from overhead broadspectrum fluorescent lamps) is still unclear, especially across various products. Methods A calibrated spectroradiometer (Ocean Insight), cosine corrector, optic fiber, and software package were used to measure the absolute irradiance (uW/cm^2/nm) emitted from overhead fluorescent lighting in a closeted dark room. Thirty-one commercially available blue blockers were individually placed between the cosine corrector and the luminaire, at a standardized distance and angle, where intensity was measured and analyzed. Each lens was evaluated individually relative to the light source under identical conditions. Then, lenses were collapsed by type into the following groups: red-tinted lenses (RTL), orange-tinted lenses (OTL), orange-tinted lenses with blue reflectivity (OBL), brown-tinted lenses (BTL), yellow-tinted lenses (YTL), and clear reflective blue lenses (RBL). Results There was significant variation in light-blocking across lens types (one-way ANOVA, p &lt; 0.0001). On average, RTL and BTL restricted 59% of the visible light measured from 380-780nm. OTL blocked 47% of the light in this range, while OBL blocked 29%. Both YTL and RBL blocked 14% of the exposure. When narrowing the range of light to 440-530nm (the part of the spectrum most likely to produce a response from melanopsin-expressing retinal ganglion cells), we estimated the following performance: the RTL and OTL blocked close to 100% of the light, OBL blocked 98%, BTL blocked 80%, YTL blocked 33%, and RBL blocked 15%. These differences were statistically significant (one-way ANOVA, p &lt; 0.0001). Individual lenses performed variably within groups, but these differences were small. Conclusion Focusing on the portion of the visible spectrum most likely to suppress melatonin secretion, RTL and OTL blocked exposure the best, followed by OBL, BTL, YTL, and (lastly) RBL. Support (if any) R01MD011600, R01DA051321