Effects of UV-B radiation on tetraspores of Chondrus ocellatus Holm(Rhodophyta),and effects of red and blue light on repair of UV-B-induced damage

We evaluated the effects of red and blue light on the repair of UV-B radiation-induced damage in tetraspores of Chondrus ocellatus Holm. Tetraspores of C. ocellatus were treated with different UV-B radiation levels(0,36,72,108,144 and 180 J/m2),and thereafter subjected to PAR,darkness,or red or blue light during a 2-h repair stage,each day for 48 days. The diameters and cellular contents of cyclobutane pyrimidine dimmers(CPDs),chlorophyll a(Chl a),phycoerythrin,and UV-B-absorbing mycosporinelike amino acids(MAAs) contents of the tetraspores were determined. Our results show that low doses of UV-B radiation(36 and 72 J/m 2) promoted the growth of C. ocellatus; however,increased UV-B radiation gradually reduced the C. ocellatus growth(greater than 72 J/m2). The MAAs(palythine and asterina-330) in C. ocellatus were detected and analyzed by LC/MS. Our results suggest that moderate red light could induce the growth of this alga in aquaculture. In addition,photorepair was inhibited by red light,so there may be some other DNA repair mechanism activated by red light. Blue light promoted the activity of DNA photolyase,greatly improving remediation efficiency. Red and blue lights were found to reduce the capacity of C. ocellatus to form MAAs. Therefore,PAR,red light,and blue light play different roles during the repair processes for damage induced by UV-B radiation.

Radiation of lamp and optimized experiment using artificial light in the Arctic Ocean

A winter optical experiment by an artificial lamp was conducted in the Amundsen Bay of Arctic Ocean from November of 2007 to January of 2008. The radiation field emitted from an artificial lamp was measured and is introduced in this paper, and the optimized experiment project is discussed. It is demonstrated that the minimum size allowed of the lamp is determined by both the field of view （ FOV ） of optical instrument and the measuring distance from the lamp. Some problems that might influence on the experiment result often occur for a simple fluorescent lamp, such as instability, spatial nonuniformity, light divergence, effect of lamp temperature, etc. By the analysis of the light radiation, three kind of measures are proposed to control the quality of the experiment, i.e. keeping consistency of lamp size with FOV of instrument, calibrating in situ downwind, and conducting measurement in effective range. Among them, the downwind calibration is the key step to overcome most problems arose by the lamp. The experiment indicated that the reliable results can be obtained only when the optical measurement is coordinated with the radiation field of artificial lamp. The measured radiation property of the lamp was used to advise the field experiment to minimize measuring error. As the experiment by artificial lamp was the first attempt in the Arctic Ocean, the experience given by this paper is a valuable reference to the correlative studies.

A Theoretical Model of Arc Light Radiation Based on GTA Spectral Diagnosis

An arc light radiation phenomenon in TIG welding process was studied through experiments and theoretical analysis.The arc spectra were acquired under a variety of welding parameters from 200 nm to 1000 nm wavelength rangein TIG. The influence of welding parameters on the arc radiation was discussed. The radiation energy from linesemission mechanisms was calculated and the comparison was made with the one from the continuum emissionmechanisms. The result shows that the radiation energy from the line emission mechanisms is equal to the one fromthe background. Based on the experiments and analysis, a physical model of arc light radiation has been developed.In this model. the arc plasma was presumed to be in local thermal equilibrium (LTE) with light thinness property.The Bolzmann distribution and Saha equation were applied to establish the arc light radiation model. This helps laythe foundation for further mathematical modeling of the arc light radiation.

Light Meter for Measuring Photosynthetically Active Radiation

Measurement of photosynthetically active radiation (PAR) incident on photosynthetic organisms is a crucial measurement for understanding how organisms respond to various light conditions, and for calculating electron flow through the photosynthetic machinery. Measurements of PAR are typically performed in the region of the electromagnetic spectrum between 400 - 700 nm, which is the region of radiation that is responsible for promoting photosynthesis. Typically, to ensure that the sensor measures in this range, the implementation of long- and short-pass filters is required. Although this allows the exclusion of radiation outside of the PAR region, such filters can be expensive. Additionally, the implementation of autonomous PAR measurements requires costly commercial instruments. Here, a straight-forward, inexpensive apparatus has been designed and constructed using a sensor that can distinguish between red, green, blue and white light. The constructed apparatus was able to perform comparably to a commercial PAR sensor. Furthermore, the implementation of the device to measure PAR intensity over a three-day period shows how the apparatus can be implemented for use as a constant light monitor.

Effects of Light Radiation Absoption on the Resistance of Sweet Potato Starch-Based Bioplastics

The strength of starch-based bioplastics is a challenge, we tried to overcome this limitation by using electromagnetic radiation in the visible range. Synthetically obtained retrograde bioplastics were subjected to radiation from an Edison-type incandescent lamp. A cross-linked network is obtained within the bioplastic matrix considerably attenuating the usual hygroscopicity of starch and increasing the ability to resist rupture. After this positive behavior, the bioplastics were colored in order to optimize the action of light radiation. The results show a stronger and more compact bioplastic. The green-colored bioplastics show the best performance in the optimization of the resistance.

Effects of Ultraviolet Radiation on Skeleton Development of Broiler Chickens

Seven hundred and twenty one-day-old AA broiler chickens were randomly allocated into two groups （male and female for half）, and put into two identical closed houses with different lighting programs. The first house was illuminated by using common incandescence light, and the second one was added with ultraviolet radiation light from the second week onwards. The birds lived in a floor with litters and free access to feed and water. Temperature, humidity and immune programs in the two houses were similar. The results showed that under ultraviolet radiation, the growth speed of skeleton increased （the shank length was significantly increased in the third week, P〈0.05; the leg muscle weight was significantly improved by 3.87%, P〈 0.05）; the skeleton quality improved （the density of skeleton mineralization was significantly increased by 6.11%, P 〈 0.01; serum calcium, phosphorus, and alkaline phosphatase activity were all improved）; and the growth performance was improved （feed conversion ratio was improved by 1.4% averagely; the uniformity of body weight, the shank length, the inclined body length and body height were significantly improved） in broiler chicken.

Solar radiation-use characteristics of indica/japonica hybrid rice (Oryza sativa L.) in the late season in southeast China

New indica and japonica hybrid rice cultivars,such as the Yongyou series,provide farmers with very high yield potential.However,information on their canopy light capture and solar radiation use efficiency in the late season is limited.Field experiments were performed to compare the radiation-use parameters of four rice types:indica rice(IR),inbred japonica rice(IJR),hybrid japonica rice(HJR),and hybrid indica/japonica rice(HIJR),from 2016 to 2018 during the late season in Hangzhou,China.The grain yield,aboveground biomass,intercepted solar radiation(SI),and radiation-use efficiency(RUE)of the HIJR were on average respectively 13.4%–53.4%,14.3%–30.6%,7.6%–21.4%,and 8.2%–14.9%higher than those of the HJR,IJR,and IR.The leaf area index(LAI)of the HIJR was 18.2%–57.0%greater than that of the IJR and HJR at four growth stages,resulting in respectively 17.8%–38.5%and 10.7%–42.8%greater canopy light interception rates(LIR)and amount of intercepted solar radiation during the vegetative stage.The prolonged grain-filling stage also led to respectively 33.9%–52.6%and 30.5%–51.4%increases in amounts of incident and intercepted radiation for the HIJR relative to the IR during grain filling.These results indicate that the SI superiority of the HIJR was caused by canopy closure as rapid as that of the IR during the vegetative stage(greater LAI and canopy LIR during the growing season)and a grain-filling stage as long as that of the HJR.For grain-filling stage,differences in leaf Pn between HIJR,IR,and IJR were not significant,suggesting that the greater RUE of the HIJR(12.7%–52.8%higher)than that of the other rice types resulted from improved canopy architecture after flowering(FL).Principal components analysis(PCA)revealed that the superiority of the HIJR in terms of solar radiation use resulted from the greater canopy light capture capability of IR and the prolonged growth period(especially during grain filling)of japonica rice in the late growing season.

Application of Exergy for Research on Increasing the Usefulness of Solar Radiation by Dispersing It into Monochromatic Beams

Energy determines the ability of matter to work. However, in the given environment, the real usefulness to perform work is determined by exergy. This study covers not only solar, but also any monochromatic thermal radiation. The value of such radiation was determined by its exergy and the ratio of its exergy-to-energy. A novelty in this work is to demonstrate by means of exergy that the usefulness of thermal polychromatic radiation can be increased by its dispersion to monochromatic radiation. This effect is the greater, the lower the temperature of the radiation. Analogies of this effect to the exergetic effect of gas separation have been indicated. The effect of the increase in exergy in the process of radiation dispersion was interpreted by means of a cylinder-piston system that explains this effect with the influence of environmental radiation. The concept of quasi-monochromatic and cumulated radiation was introduced into dispersion considerations and the change in the energetic, entropic and environmental components of the exergy of radiation beams was analyzed. Considerations were illustrated with appropriate examples of calculations considering dispersion of high-temperature radiation, such as extraterrestrial solar radiation and dispersion of low-temperature radiation from water vapor.

Radiation Use Efficiency of Cotton in Contrasting Environments

Crop growth and yield varies among locations due to differences in environmental parameters, such as temperature, relative humidity, solar radiation and vapor pressure deficit. Previous research has shown that increasing vapor pressure deficit has a negative effect on radiation use efficiency of many crops. In this study, the radiation use efficiency of cot-ton (Gossypium hirsutum L.) grown in two contrasting production environments, Arkansas and California, was evaluated for two years, in 2006 and 2007. Temperature, relative humidity, vapor pressure deficit and photosyntheti-cally active radiation were recorded at both locations. Although the crop in California accumulated more dry matter during the period of the study, the radiation use efficiency was found to be lower compared to Arkansas. Radiation use efficiency for the Arkansas and California locations was estimated at 2.060 and 1.518 g?MJ–1 of intercepted photosynthetically active radiation, respectively. The higher productivity observed in California can be attributed to larger amounts of incident and intercepted radiation in this location. Radiation use efficiency of cotton was estimated to decrease with increasing vapor pressure deficit by a slope of –0.47 g?MJ–1?kPa–1.

Electrically-driven ultrafast out-of-equilibrium light emission from hot electrons in suspended graphene/hBN heterostructures

Nanoscale light sources with high speed of electrical modulation and low energy consumption are key components for nanophotonics and optoelectronics.The record-high carrier mobility and ultrafast carrier dynamics of graphene make it promising as an atomically thin light emitter which can be further integrated into arbitrary platforms by van der Waals forces.However,due to the zero bandgap,graphene is difficult to emit light through the interband recombination of carriers like conventional semiconductors.Here,we demonstrate ultrafast thermal light emitters based on suspended graphene/hexagonal boron nitride(Gr/hBN)heterostructures.Electrons in biased graphene are significantly heated up to 2800 K at modest electric fields,emitting bright photons from the near-infrared to the visible spectral range.By eliminating the heat dissipation channel of the substrate,the radiation efficiency of the suspended Gr/hBN device is about two orders of magnitude greater than that of graphene devices supported on SiO2or hBN.Wefurther demonstrate that hot electrons and low-energy acoustic phonons in graphene are weakly coupled to each other and are not in full thermal equilibrium.Direct cooling ofhigh-temperature hot electrons to low-temperature acoustic phonons is enabled by the significant near-field heat transfer at the highly localized Gr/hBN interface,resulting in ultrafast thermal emission with up to 1 GHz bandwidth under electrical excitation.It is found thatsuspending the Gr/hBN heterostructures on the SiO2trenches significantly modifies the light emission due to the formation of the optical cavity and showed a~440%enhancement inintensity at the peak wavelength of 940 nm compared to the black-body thermal radiation.The demonstration of electrically driven ultrafast light emission from suspended Gr/hBNheterostructures sheds the light on applications of graphene heterostructures in photonicintegrated circuits,such as broadband light sources and ultrafast thermo-optic phase modulators.

Laser Radiation Influence on Transport Phenomena in a Biotissue

Different mechanisms of laser radiation influence on the chemical transport inside a biotissue are investigated. The average size of speckles existing inside a biotissue and the radiation intensity in them are estimated experimentally. Gradient forces and forces caused by the thermal expansion acting on the micro-volume inside a tissue as result of an irregular light field are calculated at different average light intensities including therapeutic. Using theoretical simulation taking into account nonequilibrium light absorption in structural elements of biotissue it has been obtained that the coherent light influences on the chemical transport more strongly in comparison with the incoherent one.

AN EMPIRICAL STUDY ON THE USE OF WATER FILM IN GLAZED BUILDINGS TO REDUCE SOLAR RADIATION TRANSMITTANCE IN THE TROPICS

Solar radiation is the cause of large heat gain in glazed buildings particularly in the tropics,thus the aim of this study is to investigate the impact of a sustainable water film on glazing transmittance to solar radiation.The experimental investigation measured two parameters,namely,type of glazing and solar radiation intensity,utilizing glazed façades oriented west in two full-scale rooms.It was found that the water film on the glazed façade increases the transmittance of solar radiation behind the glazing by 2%-6.8%depending on the solar intensity and glass type,while the indoor temperature was reduced.The study concluded that the increment of the solar radiation(300-2500nm)transmittance is an increment in the range of the visible light(daylighting).

On a Heuristic Viewpoint Concerning the Conversion and Transformation of Sound into Light

In the study of Terrestrial Gamma-ray Flashes (TGFs) and Sonoluminescence, we observe parallels with larger cosmic events. Specifically, sonoluminescence involves the rapid collapse of bubbles, which closely resembles gravitational collapse in space. This observation suggests the potential formation of low-density quantum black holes. These entities, which might be related to dark matter, are thought to experience a kind of transient evaporation similar to Hawking radiation seen in cosmic black holes. Consequently, sonoluminescence could be a valuable tool for investigating phenomena typically linked to cosmic scale events. Furthermore, the role of the Higgs boson is considered in this context, possibly connecting it to both TGFs and sonoluminescence. This research could enhance our understanding of the quantum mechanics of black holes and their relation to dark matter on Earth.

High-Temperature Target Recognition Based on Spectral Radiation Information

Based on the principles of optics and radiometry, the imaging mathematical model is established and the factors of the contrast (signal-noise-ratio) of high-temperature target and the scenery are given. By analyzing not only the differences in spectral properties between objects in the scene, but also the CCD spectral response theoretically, a new method of enhancement of contrast is given. By optimizing the initial image capture stage, using liquid crystal light valve to make a simple modification of the imaging system, the goal of high-temperature object recognition is achieved. The experimental results agree with the theoretical predict.

Application of Well-Known Antiviral Drugs in the Field Formed by the Unexplained Properties of Low-Level Laser Radiation in Therapy of Covid-19 and Chronic Viral Hepatitis

Low-level laser therapy (LLLT) or cold laser has been used in medicine for several decades. However, the method utilizes a direct contact of the light beam with a patient. Further research resulted in development of another method that enables remote transmission of the pharmacological properties of a medicament into a human body with the application of low-level laser radiation as the light source. 18 patients with different viral diseases were treated with the antiviral drugs placed into the field formed by the unexplained properties of low-level laser radiation of the “device for transfer of the pharmacological properties of a drug into the patient’s body”. This resulted in improvement of the patient’s condition, the absence of side effects and adverse reactions when using drugs in the proposed device and shortened therapy period for patients with chronic hepatitis C infection and Covid-19 patients. The long-term follow-up of the patients with chronic hepatitis B infection showed that hepatitis B virus remained at low replication levels under the influence of the therapy, which made it possible to avoid such formidable complications of the disease as cirrhosis of the liver and liver cancer.

基于Lighttools和Matlab的内辐射杂光分析方法研究

针对红外系统内辐射杂光对系统成像影响严重的问题,以一个具体红外系统为例,基于Lighttools和Matlab软件,提出一种适用于红外系统的内辐射杂光分析方法。针对分析结果所确定的需要重点消除杂光的表面,提出了相应的杂光消除措施。经验证,该方法对于寻找内辐射杂光来源,消除内辐射杂光具有很好的效果和适用性。

Investigation and optimization of sampling characteristics of light field camera for flame temperature measurement

It is essential to investigate the light field camera parameters for the accurate flame temperature measurement because the sampling characteristics of the flame radiation can be varied with them. In this study, novel indices of the light field camera were proposed to investigate the directional and spatial sampling characteristics of the flame radiation. Effects of light field camera parameters such as focal length and magnification of the main lens, focal length and magnification of the microlens were investigated. It was observed that the sampling characteristics of the flame are varied with the different parameters of the light field camera. The optimized parameters of the light field camera were then proposed for the flame radiation sampling. The larger sampling angle(23 times larger) is achieved by the optimized parameters compared to the commercial light field camera parameters. A non-negative least square(NNLS) algorithm was used to reconstruct the flame temperature. The reconstruction accuracy was also evaluated by the optimized parameters. The results suggested that the optimized parameters can provide higher reconstruction accuracy for axisymmetric and non-symmetric flame conditions in comparison to the commercial light field camera.

Tracking leaf area index and coefficient of light extinction over the harvesting cycle of black wattle

The amount of photosynthetic radiation inter- cepted by a crop is a function of the incident solar radiation on the plants, the leaf area index （LAI）, and the light extinction coefficient （k）. We quantified LAI and k in stands of black wattle （Acacia mearnsii De Wild.） over a 7-year growth cycle at two locations in the state of Rio Grande do Sul, Brazil. Our study was conducted in commercial stands in agroecological regions with high densities of black wattle plantations. LAI was calculated as the ratio between the leaf area of a tree and its planting space, and k was derived from Beer＇s law. LAI depends on the planting site and stand age. Between the two sites, the LAI was similar over time, the amount of variation differed. Values of k depended only on stand age, with the highest average observed for stands up to 5 years old. The trend of k during the plantation cycle was inversely proportional to LAI and was correlated with LAI, leaf area, leaf dry mass, canopy volume, height, branches dry mass, total dry mass, and crown diameter.

Simultaneous estimation of aerosol optical constants and size distribution from angular light-scattering measurement signals

The angular light-scattering measurement（ALSM） method combined with an improved artificial bee colony algorithm is introduced to determine aerosol optical constants and aerosol size distribution（ASD） simultaneously. Meanwhile, an optimized selection principle of the ALSM signals based on the sensitivity analysis and principle component analysis（PCA）is proposed to improve the accuracy of the retrieval results. The sensitivity analysis of the ALSM signals to the optical constants or characteristic parameters in the ASD is studied first to find the optimized selection region of measurement angles. Then, the PCA is adopted to select the optimized measurement angles within the optimized selection region obtained by sensitivity analysis. The investigation reveals that, compared with random selection measurement angles, the optimized selection measurement angles can provide more useful measurement information to ensure the retrieval accuracy. Finally,the aerosol optical constants and the ASDs are reconstructed simultaneously. The results show that the retrieval accuracy of refractive indices is better than that of absorption indices, while the characteristic parameters in ASDs have similar retrieval accuracy. Moreover, the retrieval accuracy in studying L-N distribution is a little better than that in studying Gamma distribution for the difference of corresponding correlation coefficient matrixes of the ALSM signals. All the results confirm that the proposed technique is an effective and reliable technique in estimating the aerosol optical constants and ASD simultaneously.

Effects of different light conditions on repair of UV-B-induced damage in carpospores of Chondrus ocellatus Holm

We evaluated the effects of ultraviolet-B （UV-B） radiation and different light conditions on the repair of UV-B-induced damage in carpospores of Chondrus ocellatus Holm （Rhodophyta） in laboratory experiments. Carpospores were treated daily with different doses of UV-B radiation for 48 days, when vertical branches had formed in all treatments; after each daily treatment, the carpospores were subjected to photosynthetically active radiation （PAR）, darkness, red light, or blue light during a 2-h repair stage. Carpospore diameters were measured every 4 days. We measured the growth and cellular contents of cyclobutane pyrimidine dimers （CPDs）, chlorophyll a, phycoerythrin, and UV-B-absorbing mycosporine-like amino acids （MAAs） in carpospores on Day 48. Low doses of UV-B radiation （36 and 72 J/m2） accelerated the growth of C. ocellatus. However, as the amount of UV-B radiation increased, the growth rate decreased and morphological changes occurred. UV-B radiation significant damaged DNA and photosynthetic pigments and induced three kind of MAAs, palythine, asterina-330, and shinorine. PAR conditions were best for repairing UV-B-induced damage. Darkness promoted the activity of the DNA dark- repair mechanism. Red light enhanced phycoerythrin synthesis but inhibited light repair of DNA. Although blue light, increased the activity of DNA photolyase, greatly improving remediation efficiency, the growth and development of C. ocellatus earpospores were slower than in other light treatments.