Different Types Of Light Research Articles

From slow to fast – the user controls the rate of the release of molecules from masked forms using a photoswitch and different types of light

Exposure to UV light generates a ring-closed isomer of a diarylethene, which undergoes very slow bond breaking and release even after the light is turned off. The rate of release is increased by exposing the isomer to UV and/or visible light.

Telmisartan.

Telmisartan is an angiotensin-II receptor antagonist (ARB) used in the treatment of hypertension. Generally, angiotensin-II receptor blockers such as telmisartan bind to the angiotensin-II type 1 receptors with high affinity, causing inhibition of the action of angiotensin II on vascular smooth muscle, ultimately leading to a reduction in arterial blood pressure. The present study gives a comprehensive profile of telmisartan, including detailed nomenclature, formulae, elemental analysis, and appearance of the drug are mentioned. The uses and applications and the several methods described for its preparation of the drug are outlined. The profile contains the physicochemical properties including: pKa value, solubility, X-ray powder diffraction, melting point, and methods of analysis (including compendial, electrochemical, spectroscopic, and chromatographic methods of analysis). Developed validated stability-indicating (HPLC and biodiffusion assay methods under accelerated acidic, alkaline, and oxidative conditions, in addition to effect of different types of light, temperature, and pH. Detailed Pharmacology also presented (Pharmacological actions, Therapeutic uses and Dosing, Interactions, and adverse effects and precautions). More than 80 references were given as a proof of the above-mentioned studies.

The efficiency, energy intensity and visual impact of the accent lighting in the retail grocery stores

Over the last few years, topics of displaying, presentation, lighting, energy saving and issues related to the environment while selling the fresh food (fruits, vegetable, bakery products, meat) are becoming an important matter among traders. However, just bigger companies with transnational capital have devoted their attention to this issue yet. Generally, the energy costs make up 70% of operating costs in retail stores where the cooling system and lighting are the most energy consuming. Accent lighting in modern retails is largely involved in the overall design and atmosphere in shops and plays a crucial role in presenting the goods as well. Using of accent lighting can draw the customer's attention to a specific part of the sales area and achieve the overall harmonization in the store. With the rational using of combination of energy saving and effective accent lighting retailers can achieve not only attractive presentation of displayed products but also appreciable savings in the operation of their stores. It is the only factor that can be exactly measured and controlled. Using a Colour and Lux Meters we found out the intensity and color temperature of accent lighting used in domestic and foreign retail chains for the different kinds of fresh food products. Based on the obtained values we have compiled graphs, which are showing visual comfort. We also identified different types of accent lighting, which we assigned to their impact on emotional involvement of consumers. The starting points were the tests we conducted in simulated laboratory conditions. While searching of a compromise between effective and energy efficient accent lighting we take into consideration consumers' emotional response as well as the annual electricity consumption of different types of light sources. At the end we recommend options for energy-efficient, effective and spectacular lighting while using the optimal number of light sources and their logical organization, automatic control as well as using energy-saving LED lights or practical skylights. Improvements in energy efficiency of technical equipments could reduce the operating costs for retailers as well as enhance the attractiveness of displayed goods and customer satisfaction and thereby increase their sales.

Investigation of luminescent properties of Ca0.3Sr0.7Al2O4:Tb3+,Eu3+ excited using different excitation sources

The structure and luminescent properties of Tb3+–Eu3+ co-activated Ca0.3Sr0.7Al2O4 powder phosphor prepared via solution combustion (SC) method were investigated. The phosphor was analyzed using UV–vis spectroscopy, Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron (XPS), time of flight secondary ion mass spectroscopy (ToF-SIMS), photoluminescence spectroscopy, synchrotron radiation spectroscopy and cathodoluminescence spectroscopy. In particular, the unintended reduction of Eu3+ to Eu2+ was illustrated from the ToF-SIMS, XPS and luminescent spectroscopy data. This reduction is known to occur under certain conditions and possible mechanisms for the reduction are discussed. The chemical imaging performed with ToF-SIMS illustrated how individual ions were distributed in the crystal. Tunable luminescence was observed when the phosphor was optically-excited by different excitation sources including a 325nm He-Cd laser, synchrotron radiation and high energy electrons. This phosphor was evaluated for application in different types of light emitting devices.

ZnO Gate Based MOSFETs for Sensor Applications

A metal–oxide–semiconductor field-effect transistor (MOSFET) with transparent ZnO as its gate metal was fabricated and its photodetecting capabilities were investigated. For the fabrication of the MOSFET, a four level mask was used. The first level was used for making the diffusion wells for source and drain. The second level to form the via holes for Aluminum deposition followed by the third level to shape the source and drain contact structures. Finally the fourth level mask to pattern the ZnO gate metal. The ZnO gate metal was deposited by sputtering process. The electrical characteristic analysis was performed on the fabricated MOSFETs when different types of light were incident on it.

Harmonic phase angles for a domestic customer with different types of lighting

Summary This paper presents measurements of the changes in phase angle of the harmonic current for a domestic costumer due to the introduction of energy-efficient lamps (compact fluorescent lamps and light-emitting diodes lamps). Those results are then compared with the aggregation rules according to standard IEC 61000-3-6 and with a mathematical model, in order to highlight the importance of using phase angles in the harmonic estimations. The paper presents both the emission from individual household devices and the variations in the complex harmonic current from a group of devices. Cancellation because of phase-angle difference plays an important role in the emission from a group of different devices. This explains why the increase in emission after changing to energy-efficient lamps is much smaller than expected. Some other power-quality parameters are also considered such as total harmonic distortion, total power factor, and displacement power factor. It is concluded that the complex plane presentation is a useful tool to estimate the harmonic emission from a group of domestic appliances. Copyright © 2014 John Wiley & Sons, Ltd.

Matter correlations induced by coupling to quantum light

Correlations between uncoupled particles induced by the interaction with different types of light are investigated using a superoperator formalism. We derive compact expressions for the doubly-excited-state distributions of noninteracting multilevel atoms excited by classical laser light, classical stochastic light, and quantum light. We find that the g2 function of the incoming light can be directly related to its ability to induce correlations in the matter. Unlike coherent light, quantum light can induce entanglement between the atoms. The photon coincidence signal created by classical fields may be factorized into a product of single photon counting rates. This is not the case for quantum light. © 2014 American Physical Society.

Chapter One - Azithromycin

Azithromycin is an azalide, a subclass of macrolide antibiotics. It is derived from erythromycin, with a methyl-substituted nitrogen atom incorporated into the lactone ring, thus making the lactone ring 15-membered. It prevents bacteria from growing by interfering with their protein synthesis. It binds to the 50S subunit of the bacterial ribosome and thus inhibits translation of mRNA. Azithromycin is used to treat or prevent certain bacterial infections, most often those causing middle ear infections, strep throat, pneumonia, typhoid, bronchitis, and sinusitis. In recent years, it has been used primarily to prevent bacterial infections in infants and those with weaker immune systems. It is also effective against certain sexually transmitted infections, such as nongonococcal urethritis, chlamydia, and cervicitis. Recent studies have indicated it also to be effective against late-onset asthma, but these findings are controversial and not widely accepted. The present study gives a comprehensive profile of azithromycin, including detailed physico-chemical properties, nomenclature, formulae, methods of preparation, and methods of analysis (including compendial, electrochemical, spectroscopic, and chromatographic methods of analysis). Developed validated stability-indicating (HPLC and biodiffusion assay methods under accelerated acidic, alkaline, and oxidative conditions, in addition to effect of different types of light, temperature, and pH. Detailed clinical applications also presented (mechanism of action, ADME profile, clinical uses and doses, side effects, and drug interactions). Each of the above stages includes appropriate figures and tables. More than 80 references were given as a proof of the above-mentioned studies.

Relative Evaluation of Comfort Level Associated with Light-Emitting Diode Lighting Based on near Infrared Spectroscopy

Although the use of light-emitting diode (LED) lighting has rapidly become popular as the next-generation of lighting, the degree of comfort associated with these lights has not been sufficiently examined. Therefore, establishing both subjective and objective evaluation methods to test the comfort associated with LED lightings is desirable. We investigated the comfort associated with LED lighting by using near infrared (NIR) spectroscopy. The study recruited 35 healthy young adults with no ophthalmological diseases. Three types of lighting, including edge-lit LED, direct-lit LED and fluorescent lighting, were used for the subjective evaluation and measurements of the brain function in both Experiment 1 (comfort verification of lighting illuminance) and Experiment 2 (comfort verification of lighting type). Brain measurements were performed using an NIR sensor and by assessing the oxygenated haemoglobin concentration changes in the frontal lobe during the time the subjects looked at each type of light. The subjective evaluation determined that lighting luminance at 800 lux significantly lowered the comfort level, while direct-lit LED and fluorescent lighting significantly lowered the comfort level as compared with edge-lit LED lighting. Lighting illuminance of 800 lux induced a significant increase in oxygenated haemoglobin concentration compared with the control conditions when eyelids were closed. In addition, looking at direct-LED and fluorescent lighting significantly increased oxygenated haemoglobin concentration compared with edge-lit LED lighting. Our study suggests that the subjective comfort level experienced while looking at different types of lighting could potentially be evaluated based on changes in oxygenated haemoglobin concentration within the frontal lobe detected using NIR sensors.

Understanding the expected performance of large-scale solar ponds from laboratory-scale observations and numerical modeling

Solar ponds are low-cost, large-scale solar collectors with integrated storage that can be used as an energy source in many thermal systems. Experimental solar pond investigations at smaller scales have proven to be useful when trying to understand how different factors affect the pond’s efficiency, but they do not necessarily represent the expected performance of large-scale solar ponds. Consequently, it is important to investigate how the results of small-scale solar pond experiments can be scaled up. In this work, we show how models based on laboratory-scale observations can be utilized to understand the expected performance of large-scale solar ponds. This paper presents an approach that combines high-resolution thermal observations with computational fluid dynamics to investigate how different physical processes affect solar pond performance at different scales. The main factors that result in differences between small- and large-scale solar pond performances are boundary effects, light radiation spectrum and intensity, and turbidity. Boundary effects (e.g., pond geometry, thermal insulation) reduce the energy that reaches the storage zone of small-scale solar ponds. Different types of lights result in different radiation spectrum and intensity, which affects the energy reaching the storage zone. Turbidity is typically not important in small-scale solar ponds subject to controlled environmental conditions. However, it is an important factor in outdoor solar ponds in which the pond is prone to particles that can deposit onto the water surface or become suspended in the gradient zone. In general, the combination of these factors results in less energy collected in small-scale solar ponds than in large-scale solar ponds, even though large-scale solar ponds are typically subject to more extreme environmental conditions. High-resolution thermal observations combined with numerical simulations to understand the expected performance of large-scale solar ponds seems to be a promising tool for improving both efficiency and operation of these solar energy systems.

Evaluation of the Surface Roughness for Three Different Types of Composite Resin Materials Using (Sof–Lex) Finishing and Polishing Systems: A Comparative Study

Aim: To evaluate the surface roughness of three different types of light activated composite resin using (Sof-Lex) – polishing system, a profilometer study. Materials and Methods: A total of 30 resin com-posite disks were prepared from three different types of composite resin include 3 – groups. Group I: 10 specimens were prepared from light activated nano hybride (Tetric n – Ceram, Ivoclar – Vivadent – Liechtenstein). Group II: 10 specimens were prepared from light activated microhybride composite resin (Arabesk – Voco, Germany). Group III: 10 specimens were prepared from light activated poly-glas composite resin (Solitaire – 2, Heraeus, Kulzer, Germany). The resin blocks finished and polished using (Sof – Lex) polishing system. The specimens were analyzed for surface roughness using “Pro-filometer”. Results: Tetric n – Ceram composite resin showed the lowest roughness average (0.112 μm) followed by Arabesk composite (0.150 μm), Solitaire – 2 composite resin showed the highest roughness average (0.341 μm). Conclusions: Tetric n– Ceram (nano-hybride) was the best polished composite resin, showed the least roughness average.

Effects of different light types on root formation of Ocimum basilicum L. cuttings

Sweet basil is usually propagated by cuttings due to the ease of this method and the ability to establish mature plants quickly. However, slow root formation in this method limits early stage plant growth. To improve the efficiency of root formation, we evaluated the effects of different types of light on sweet basil cuttings. Basil cuttings were initially separated into NAA or non-NAA treatment groups to evaluate hormonal effects on rooting. Then, basil cuttings were irradiated with red, blue, fluorescent light, or natural sunlight for 16h per day. Adventitious root and shoot fresh weights as well as chlorophyll content were measured at 2, 4, and 6 weeks. Blue light was the most effective at improving root formation. Root establishment was about three times faster upon treatment with blue light than natural sunlight; root growth under blue light for 2 weeks was similar to that under natural sunlight for 6 weeks. NAA treatment of the cutting surface significantly improved root growth under blue light as compared with non-NAA treatment. The effects of NAA treatment on growth under other light types were not significantly different. However, longer exposure to blue light resulted in leaf etiolation of older leaves. Our results indicate that use of blue LEDs to irradiate basil cuttings significantly reduced the time required for both root formation and the development of conventional cuttings compared to other light types.

Study on harmonic emission of domestic equipment combined with different types of lighting

This paper presents the results of a set of measurements to study changes in harmonic emission from domestic equipment due to the introduction of energy-efficient lamps. During this study measurements have been performed of the emission from different combinations of domestic devices in combination with different kind of lamps. Those results are then compared with standards, with a mathematical aggregation model and with results from field experiments in order to give recommendations to different stakeholders. The measurements clearly show that the total emission depends on the lamps that are connected as a background. It is however not possible to draw the general conclusion that the introduction of CFLs and LED lamps will result in an increase or decrease of emission. It is also concluded in this work that the IEC aggregation model does not give useful estimations of changes in emission from domestic installations due to the introduction of CFLs and LED lamps. The measurement results further indicate that emission levels at higher frequencies might increase due to the large-scale introduction of such lamps.

Study of the Effect of Brightness After Penetration of Light from a Lens

There are many types of component that are able to produce light and the light is produced based on the angle and wavelength of the lens. Light penetration depends on the type of material used. The tests are done using basic electronic components which are able to produce light including the light emitting diode (LED), laser and infrared source. From the component, there are two types of light line, one with an angle and one without. It is known that the laser only produces a straight line light while the angle and thickness of light from both the LED, and infrared source increase with distance. The results show that the different types of light must use different types of lenses and they are suitable for use with all light properties.

Effect of MeJA and Light on the Accumulation of Betulin and Oleanolic Acid in the Saplings of White Birch (<i>Betula platyphylla</i> Suk.)

In this study, we investigated the effect of different types of light and MeJA treatment on the accumulation of betulin and oleanolic acid in various organs of white birch. Our results showed that betulin and oleanolic were accumulated mainly in the stalk skin. The content of both substances in the stalk skin was significantly affected by seasons with a peak accumulation in August. The content of oleanolic and betulin was significantly decreased in the stem skin treated with 4 types of light (red, yellow, blue and green) compared with the plant with normal illumination. In contrast, oleanolic acid in leaves was increased by 13.28 folds when the white birch was treated with green light. Betulin was increased by 1.959 folds in leaves of white birch treated with blue light. The highest content of betulin and oleanolic acid in various organs of birch with appropriate shading treatment (light transmittance: 50%) was increased by 45.09% and 30.50%, respectively, in comparison with those with non-shading treatment. Content of oleanolic acid and betulin can be significantly improved in various parts of birch after treatment with different concentration of MeJA. The study lays the foundation to metabolic regulation of oleanolic acid and betulin in birch.

145 EXTRA LIGHT EXPOSURE DECREASES DEVELOPMENT AND QUALITY OF PORCINE PARTHENOTE EMBRYOS

During in-vitro handling, oocytes and embryos are always exposed to light. This has been shown to affect embryonic development and quality in different species, i.e. hamster and mouse (Takenaka et al. 2007 PNAS, 104, 14 289–14 293) and human (Tatsuo et al. 2010 J. Assist. Reprod. Genet. 27, 93–96). However, similar experiments have not been made on porcine embryos, so our aim was to test effects of different types of light on the development and quality of porcine parthenote embryos. Cumulus–oocyte complexes from slaughterhouse-derived sow ovaries were aspirated and matured (38.5°C, 5% CO2, maximum humidity, 42 h). Parthenogenetic activation was made (Day 0) first by an electric pulse (1.26 kV cm–1, 80 µs) and then by incubation with 5 µg mL–1 cytochalasin B and 10 µg mL–1 cycloheximide in porcine zygote medium-3 (PZM-3) for 4 h. During these processes, the oocytes would be exposed to ~30 min of light. After activation, the oocytes were either directly cultured in incubator (0 h), or experimentally exposed to two types of light (DAY: near window, no direct sunlight; LAB: app. 40 cm from warm white lamps (12 V, 40 W) in PZM-3 while placed on a heating plate (38.5°C) with the culture dish covered by a crystal plastic foil filled with the appropriate gas (5% O2, 5% CO2) for different periods (1 h, 4 h, 24 h), and then cultured in PZM-3 in incubator. On Day 6, total and good blastocysts were counted. Good blastocysts were defined as blastocysts having expanded to 1.5 times the oocytes’ size, having cells of uniform color and distribution, and having formed a regular blastocyst cavity. The total number of cells and the apoptotic cells were detected on Day 6 blastocysts with TUNEL assay to evaluate embryonic quality. All statistics analysis were performed by ANOVA test (R). The results are summarized in Table 1. The developmental rates were decreased with both types of light: the decrease appeared earlier for good blastocyst rates, only after 1 h exposure; however, a clear adverse effect was also found on total blastocyst rates after 24 h exposure. The total cell number decreased after 4 h light exposure for both types of light. The rate of apoptotic cells tended to increase with both types of light (from approximately 7 to 9.5%) when embryos were exposed during 24 h, but no significant difference was found between groups. We conclude that the blastocyst morphology would be altered already after 1 h extra exposure to both light types, and their quality would further decrease after 4 h exposure. However, under normal working conditions, this should not represent a real problem. Table 1.Effect of light exposure on development of porcine parthenote embryos

Electrically induced light scattering performances of lanthanum-modified lead zirconate titanate transparent ceramics

A series of lanthanum-modified lead zirconate titanate (PLZT) ceramics of Zr/Ti (70/30) with different La concentration (La = 7.6, 7.8, 8.0 mole %) were prepared by a hot pressing process. The performances of electrically induced light scattering for PLZT (X/70/30) ceramics were investigated and analyzed systematically. All samples are crystallized into a single perovskite phase. The PLZT (7.6/70/30) sample exhibits a ferroelectric behavior while both PLZT (7.8/70/30) and PLZT (8.0/70/30) samples show an antiferroelectric behavior. The phase transition temperature (Tc) of the PLZT (X/70/30) ceramics shifts slightly from ~86 °C to ~89 °C with the increasing of La concentration at 1 kHz. All three ceramic samples exhibit a high transmittance, i.e., greater than 60 %, with a thickness of 0.4 mm over a wide range of wavelength band, from visible to near IR. The PLZT (X/70/30) ceramics exhibit three different types of light scattering behavior depending on the La concentration (examined at λ = 632.8 nm). Among them, PLZT (8.0/70/30) presents a unique applicable auto-switchable property with a low threshold value of electric field and high transmittance. Noticeably, the contrast ratio increases correspondingly with the thickness of the sample, and the contrast ratio aroused by the transverse electric field is about twice as big as that aroused by the longitudinal one. The light scattering properties of the PLZT (8.0/70/30) ceramic may represent a creative application in optical modulators.

VISUALIZATION AND ANALYSIS OF LIGHT POLLUTION: A CASE STUDY IN HONG KONG

Abstract. The effects of light pollution problems in metropolitan areas are investigated in this study. Areas of Hong Kong are used as the source of three typical study cases. One case represents the regional scale, a second represents the district scale, and a third represents the street scale. Two light pollution parameters, Night Sky Brightness (NSB) and Street Light Level (SLL), are the focus of the analyses. Light pollution visualization approaches in relation to the different scales include various light pollution maps. They provide straightforward presentations of the light pollution situations in the study areas. The relationship between light pollution and several social-economic factors such as land use, household income, and types of outdoor lighting in the scale areas given, are examined. Results show that: (1) Land use may be one factor affecting light pollution in the regional scale; (2) A relatively strong correlation exists between light pollution and household income in the district scale; (3) The heaviest light pollution in the street scale is created by spotlights and also the different types of lighting from shops. The impact of the latter is in relation to the shop profile and size.

Effect of ZnO and TiO2 nanoparticles preilluminated with UVA and UVB light on Escherichia coli and Bacillus subtilis

We evaluated the effects of zinc oxide (ZnO) and titanium dioxide (TiO₂) nanoparticles (NPs) preilluminated with ultraviolet light on Escherichia coli and Bacillus subtilis. The experiments were conducted using three different types of light: visible, Ultraviolet A (UVA, 315-400 nm), and Ultraviolet B (UVB, 280-315 nm). The bacteria were exposed to NPs, either as liquid suspensions for growth inhibition assays or on agar plates for colony forming unit (CFU) assays. We found that the ZnO NPs were more toxic when preilluminated with UVA or UVB light than with visible light in both growth inhibition and CFU assays. TiO₂ NPs were not toxic to the bacteria under UVA or UVB preillumination conditions. The photo-dissolution of ZnO NPs increased with UV preillumination, which could explain the observed toxicity of ZnO NPs. We detected oxidative stress elicited by photoactive nanoparticles by measuring superoxide dismutase activity. The results of this study show that the toxicity of photoactive nanoparticles can be increased by UV preillumination by dissolution of toxic ions, which suggests the potential for preillumination-dependent toxicity of nanoparticles on soil environments in low light or darkness.

Effects of different luting cements and light curing units on the sealing ability and bond strength of fiber posts

This study evaluated the sealing ability and push-out bond strength of two luting cements cured with two different types of light curing units (LCU): light-emitting diode (LED) versus quartz tungsten halogen (QTH). Forty teeth were divided into four groups(n=10/group). Quartz fiber posts (D. T. Light-Post) were luted to coronal or apical section of root canals using two types of resin cements (Panavia F or RelyX) cured with either LED LCU (Elipar FreeLight II) or QTH LCU (Optilux 501). Highest push-out bond strength was exhibited by QTH-cured RelyX, which was not significantly different from LED-cured RelyX but was higher than QTH-cured Panavia F. The push-out bond strength of Panavia F did not differ with LCU type (p>0.05), but exhibited lower values than both QTH- and LED-cured RelyX. Fluid filtration test revealed that sealing ability was not influenced by luting cement type, but was significantly influenced by LCU type in favor of QTH light source: QTH-cured specimens displayed better seal than LED-cured ones (p<0.05).