The Talking Film

Background: Salvia miltiorrhiza Bunge has been used in traditional medicine. The type of light source has an effect on the growth properties and composition of functional compounds in plants. In this study, we analyzed the effects of different artificial light sources on the growth characteristics as well as antioxidant and antimicrobial activities of S. miltiorrhiza.<BR>Methods and Results: Seedlings of S. miltiorrhiza were grown under various artificial light sources, including fluorescent light (FL), light emitting diode (LED), and microwave electrodeless light (MEL), for 8 weeks. Growth characteristics were the best in plants treated with MEL. DPPH scavenging activity of the shoot was more pronounced with the FL treatments, while the roots were more active in plants grown under single wavelength lights (i.e., blue and red LEDs). Among the different light source treatments, the blue LED resulted in a higher total phenolic content in the plants. Furthermore, growing plants growth under the red LED enhanced their total flavonoid content. Notably, the antimicrobial properties of plants varied significantly between light source treatments in this study. Except for E. coli, all the tested microorganisms were susceptible to the plant extracts.<BR>Conclusions: The type of light source may be an important parameter for the enhancement of plant growth and functional compounds in S. miltiorrhiza.

In the Formula Student Racing Car, the frame is a fundamental component that supports the body. The frame’s anti-deformation ability will impact the four-wheel positioning parameters of the car, which subsequently affect the car’s stability. The quality of the frame directly determines the power and efficiency of the racing car, making the frame crucial to the overall race performance. Therefore, researching lightweight frame design is particularly important to enhance frame performance and reduce its total weight. In this paper, based on the variable density method, the global topology optimization of the frame is carried out to obtain the distribution of the frame material, realize the efficient utilization of the material, and improve the torsional stiffness of the frame. Compared with the previous local topology optimization, the global topology optimization involves a wider range, and the results are more accurate. Based on the adjoint variable method, the sensitivity analysis of the frame is carried out to obtain the influence level of each design variable. The size of the frame is optimized according to the variables with high influence levels. After optimization, the total mass of the frame is reduced by 12.8%; the performance in terms of maximum displacement and maximum stress is improved; and the lightweight design of the frame is realized as a whole.

In this study, a topology optimization method based on combined mechanical analysis and variable density is presented for a large-scale casting structure with complex thin-walled structures. First, the mechanical analysis model of the frame is established, the first-order bending and torsional modes and stiffness values of the all-cast aluminum frame are obtained, and the basic mechanical parameters such as bending/torsional mode and stiffness constraints needed for topology optimization are defined. Using the variable density method, unneeded material that can be removed from the casting structure is identified. According to the design requirements, the optimization objective function and constraint conditions are established, and the variable density method is used to solve the problem. Analysis of the mechanical results before and after topology optimization reveals that the modes and stiffness values are larger than the target values, and the mass of the frame is reduced by 10.2 kg (i.e. 13.9%) compared with the original design. The application of the combined mechanical analysis and variable density method to a casting structure can effectively achieve lightweight design.

Eustoma grandiflorum (Raf.) Shinn. was subjected to long-day treatment using four types of light sources with a high red (R; 660 ± 30 nm) to far-red (FR; 730 ± 30 nm) light ratio to improve cut flower quality for early-autumn shipping. The R:FR ratios of a red-light fluorescent lamp, a color fluorescent lamp (R-type), a bulb-type red-light fluorescent lamp, and a bulb-type daylight fluorescent lamp were 62.0, 100.0, 8.8, and 8.5, respectively. As a control, plants were grown under ambient daylight. Flower budding of ‘Double Pink’ seedlings, planted on July 11 and treated with night-break treatment from planting to budding using these four light sources, was delayed 2–5 days compared with the control. Night-break treatment using each light source increased the number of nodes on the main stem, number of lateral branches, and number of flower buds, and increased the cut flower length of plants at anthesis of the first floret, compared with the control. Three cultivars were treated with night break using a color fluorescent lamp (R-type) and a bulb-type red-light fluorescent lamp. Although these two light sources did not delay the flowering of ‘King of Snow’ compared with the control, the mean flowering date of ‘Double Pink’ and ‘Piccolosa Snow’ under both light sources was 3–6 days later than that of the control. These light sources increased the number of nodes of the main stem, and increased the stem length and cut flower length compared with the control in each cultivar. As the most practical application, the bulb-type red-light fluorescent lamp was used for long-day treatment of ‘Double Pink’ under four lighting periods: pre-dawn lighting for 6 h, end-of-day lighting for 6 h, all-night lighting, and night break for 6 h during the night. All-night lighting delayed flowering more than the other treatments. Cut flower length of the plants at anthesis of the first floret was longest in the pre-dawn lighting treatment. We concluded that long-day treatment using a bulb-type red-light fluorescent lamp from 0:00 to 6:00 just after planting until flower budding is most effective to improve cut flower quality for early-autumn shipping of Eustoma cultivars.

A light source has been built at the simulation chamber AIDA (Aerosol Interactions and Dynamics in the Atmosphere) at the Karlsruhe Institute of Technology, simulating solar radiation at ground level. Instead of full spectra light sources, it uses a combination of LEDs with a narrow emission spectrum, resulting in a combined spectrum similar to the solar spectrum between 300 and 530 nm. The use of LEDs leads to an energy-efficient, robust and versatile illumination concept. The light source can be used over a wide temperature range down to −90 °C, is adjustable in intensity and spectral width as well as easily adjustable to new technological developments or scientific needs. Characterization of the illumination conditions shows a vertical intensity gradient in the chamber. The integral intensity corresponds to a NO2 photolysis frequency j(NO2) of (1.58 ± 0.21 (1σ)) x 10−3 s−1 for temperatures between 213 and 295 K. At constant temperature, the light intensity is stable within ±1 %. While the emissions of the different LEDs change with temperature, they can be adjusted, thus it is possible to adapt the spectrum for different temperatures. Although, the illumination of the simulation chamber leads to an increase of 0.7 K h−1 of the mean gas temperature, it is possible to perform experiments with aqueous droplets at relative humidities up to ≤ 95 % and also above water or ice saturation with corresponding clouds. Additionally, temperature and wavelength dependent photolysis experiments with 2,3-pentanedione have been conducted. The photolysis of 2,3-pentanedione occurs mainly between 400 and 460 nm resulting in a mean photolysis frequency of (1.03 ± 0.15) x 10−4 s−1 independent of temperature in the range 213–298 K with a quantum yield of 0.36 ± 0.04. In contrast the yield of the two main photolysis products, acetaldehyde and formaldehyde, decreases with temperature. Furthermore, the light source was applied to study the photochemistry of aerosol particles. For the atmospheric brown carbon proxy compound 3,5-diacetyl-2,4,6-trimethyl-1,4-dihydropyridine photochemical reaction products were identified. In aerosol particles containing iron oxalate as photosensitizer the photosensitized degradation of organic acids (pinic and pinonic acid) was studied. Although, the light source only generates about 1/3 of the maximum solar irradiation at ground level with a substantial intensity gradient throughout the simulation chamber it could be shown that this type of light source allows reproducible experiments over a wide range of simulated atmospheric conditions and with a large flexibility and control of the irradiation spectrum.

Recently, dye-sensitized solar cells demonstrated a superior performance under ambient light conditions. In this study, the influence on dye-sensitized solar cell performances was investigated under different light sources, light intensity, spectra, and water flow lens (WFL) system. Three types of light sources (xenon, halogen, and tungsten) with various spectral distributions (spectra) were used. Dyes-sensitized solar cells with varied sensitizers and co-sensitizers were tested depending on the light sources. Higher efficiency was obtained under irradiance of tungsten and halogen lamp in comparison to the xenon lamp, specifically at lower light intensities. Additionally, a new way of spectral adjustment was demonstrated. The use of a WFL system changes the distribution of spectra and remarkably influence for better performances of solar cells and efficiency values up to 30&#x0025;. The results revealed that at lower light intensity, the influence of spectra was dominant and by changing spectral distribution various values of efficiency can be obtained. Also, a great influence on solar cells characteristics had a light source used for measurements. IEEE

United States Navy submariners have historically lived with circadian disruption while at sea due to 18-h-based watchschedules. Previous research demonstrated that circadian entrainment improved with 24-h-based watchschedules. Twenty-nine male crew members participated in the study, which took place on an actual submarine patrol. The crew were exposed, first, to experimental high correlated color temperature (CCT = 13,500 K) fluorescent light sources and then to standard-issue fluorescent light sources (CCT = 4100 K). A variety of outcome measures were employed to determine if higher levels of circadian-effective light during on-watch times would further promote behavioral alignment to 24-h-based watchschedules. The high CCT light source produced significantly higher circadian light exposures than the low CCT light source, which was associated with significantly greater 24-h behavioral alignment with work schedules using phasor analysis, greater levels of sleep efficiency measured with wrist actigraphy, lower levels of subjective sleepiness measured with the Karolinska Sleepiness Scale, and higher nighttime melatonin concentrations measured by morning urinary 6-sulfatoxymelatonin/creatinine ratios. Unlike these diverse outcome measures, performance scores were significantly worse under the high CCT light source than under the low CCT light source, due to practice effects. As hypothesized, with the exception of the performance scores, all of the data converge to suggest that high CCT light sources, combined with 24-h watchschedules, promote better behavioral alignment with work schedules and greater sleep quality on submarines. Since the order and the type of light sources were confounded in this field study, the results should only be considered as consistent with our theoretical understanding of how regular, 24-h light-dark exposures combined with high circadian light exposures can promote greater behavioral alignment with work schedules and with sleep.

Development of a compact X-ray linear light source and FEL at UCLA

Recently the new type of light source has been introduced to the market. Organic light emitting diode (OLED) is not only interesting because of the low applying voltage, wide light emitting areas and emission efficiency. It gives the possibility to create a light source of a various shape, various color and in the near future very likely even the one that will change shape and spectrum in time in controlled way. Those opportunities have not been in our reach until now. In the paper authors try to give an answer to the question if the new light source -OLED - is suitable for interferometric purposes. Tests cover the short and long term spectrum stability, spectrum changes due to the emission area selection. In the paper the results of two OLEDs (red and white) are shown together with the result of an attempt to use them in an interferometric setup.

Topology optimization design of the main structure of 6-DOF manipulator based on the variable density method

For the lightweight design of composite sandwich corrugated structures, a new topology optimization design scheme is proposed using the variable density method. Multi-working conditions static analysis of the composite sandwich corrugated structure is carried out by finite element software. Then, the topology optimization is carried out by using the minimum flexibility method. Finally, the results of different working conditions are coupled to propose a new composite sandwich corrugated structure. The results indicate that the structure has a weight reduction of 34% and exhibits periodicity and continuity while also meeting the necessary mechanical properties to fulfill the engineering requirements. The optimization of composite sandwich corrugated structures has been achieved, providing a new approach to the lightweight design of composite sandwich structures.

Wear characteristics of some metals in relation to surface temperature

In this paper, we investigate the effect of pulse-to-pulse fluctuations of supercontinuum sources on the noise in spectral domain optical coherence tomography (OCT) images. The commonly quoted theoretical expression for the OCT noise is derived for a thermal light source, which is not suitable if a supercontinuum light source is used. We therefore propose a new, measurement-based OCT noise model that predicts the noise without any assumptions on the type of light source. We show that the predicted noise values are in excellent agreement with the measured values. The spectral correlation evaluated for the photodetected signal when using a supercontinuum determines the shape of the OCT noise floor, which must be taken into account when characterizing the sensitivity roll-off of a supercontinuum-based OCT system. The spectral correlations using both conventional supercontinuum sources and low-noise all-normal dispersion supercontinuum sources are investigated, and the fundamental physical effects that cause these correlations are discussed.

The analysis of technical characteristics and cost of modern light sources and motion sensors used in administrative premises is carried out. It has been established that lighting of corridor-type rooms using LED panels of the lower and middle price ranges with a luminous efficiency of 80-85 and 100 lm/W, accordingly, becomes less expensive in the second year of operation compared to fluorescent lighting. Installation of panels with a higher luminous efficiency, up to 120 lm/W, at the current level of prices on them has certain risks, as the payback period of the investment in this case is about 7 years, exceeding the warranty period of these panels. The payback period of investment in the automation of lighting control in corridor-type rooms using relatively inexpensive infrared motion sensors and the expected reduction of energy consumption by 30% does not exceed 5 years, demonstrating the feasibility of this event. Measures for replacing fluorescent lamps with LED panels in less loaded classrooms, up to 510 hours of operation per year, have a payback time of 4-6 years, which exceeds the warranty period of the panels. Therefore, according to the authors of the article, it is appropriate to first replace the lamps in the corridors, and then, after accumulating experience in operating the purchased light sources, to replace them in the classrooms. Due to their high cost in the premises of educational institutions, the use of presence sensors as well as automated lighting level control systems is not economically feasible. The urgency of saving energy by replacing fluorescent lamps with LED and automation of lighting control, due to the trend towards an increase in the cost of electricity, will also grow. The algorithms and formulas given in the article for determining the present value, payback periods are simple and can be applied to other types of light sources and design conditions.

Illumination design is a job that is related to culture, and forms the bridge between illumination theories on civilization and illumination theories on culture. As a result of rapid developments in illumination technology, new light sources such as LEDs are now attracting attention, and the many calls for the elimination of incandescent lamps have led to a rather alarming situation. In illumination design, various types of light sources should be used in coordination to take advantage of their unique characteristics. In this sense, LEDs and incandescent lamps are light sources that should co-exist even in the future. In illumination design, what is more important than anything else is having the mindset to learn from natural lighting.