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Introduktion - Detta examensarbete handlar om belysningens påverkan på människorsrumsupplevelse och trygghet i trånga och stängda utrymmen, med särskilt fokus påhissar. Syftet med studien var att undersöka hur ljusfördelning och ljusintensitetpåverkar människors upplevelse av hissar och hur ljuset kan skapa en mer behaglig ochtrygg miljö för dessa utrymmen. Metod - Undersökningen utfördes genom en kombination av en enkätundersökning ochett experiment med djupgående intervjuer. Båda delarna av studien innehöll sexbelysningsscenarier med olika ljusfördelningar och intensiteter. Enkätundersökningengenomfördes med 23 deltagare som besvarade frågor gällande upplevd atmosfär, känslaoch trygghet i hissen med hjälp av en semantisk skala. Experimentet utfördes på ettmindre urval deltagare med samma scenarier visade genom ett VR-headset. Resultat och Analys - Den insamlade datan från enkäten och intervjuerna visar attdeltagarna föredrog en jämnare och högre ljusintensitet. Många upplevde en förbättradtrygghet i hissen med ett jämnare ljus, eftersom det tydliggjorde människors ansikten.Den mer varierade ljusfördelningen upplevdes som luminant och ojämn. Resten av deninsamlade datan visar på att deltagarna upplevde scenarierna på väldigt olika sätt. Diskussion - Resultaten bekräftar en del tidigare forskning gällande att högreljusintensiteter bidrar till en ökad trygghet. Men i motsats till tidigare forskning somvisar på att en mer varierad ljusfördelning skapar en positivare atmosfär, visar dennastudie på att en jämnare ljusfördelning bidrar till en bättre atmosfär i hissar. En möjligförklaring till detta resultat kan vara att en jämn ljusfördelning tydliggör ansikten ochskapar en känsla av ökad trygghet. Detta resultat är viktigt att ta hänsyn till förljusdesign i offentliga utrymmen, speciellt i hissar där det är viktigt att skapa en tryggoch bekväm atmosfär. Trots att hissen är ett utrymme som brukas under en kortare tidär det viktigt att den upplevs trygg och behaglig för, Introduction - This thesis investigated the impact of lighting on people's spatialexperience and sense of safety in confined and enclosed spaces, with a particular focuson elevators. The aim of the study was to examine how light distribution and intensityaffect people's experience of elevators and how light can create a more comfortable andsecure environment for these spaces. Method - The study was conducted through a combination of a survey and anexperiment with in-depth interviews. Both parts of the study included six lightingscenarios with varying light distributions and intensities. The survey was conductedwith 23 participants who answered questions about their perceived atmosphere,feelings, and sense of safety in the elevator using a semantic scale. The experiment wasconducted on a smaller sample of people with the same scenarios shown through a VRheadset. Results and Analysis - The collected data from the survey and interviews show thatparticipants preferred a more even and higher light intensity. Many experiencedimproved safety in the elevator with a more even light, as it highlighted people's faces.A more varied light distribution was experienced as luminous and uneven. The rest ofthe collected data shows that participants experienced the scenarios in very differentways. Discussion - The results confirm previous research that higher light intensitiescontribute to increased safety. Contrary to previous research, it showed that a morevaried light distribution creates a more positive atmosphere, this study shows that amore even light distribution contributes to a better atmosphere in elevators. Onepossible explanation for this result could be that an even light distribution highlightsfaces and creates a sense of increased safety. This result is important to consider forlighting design in public spaces, especially in elevators where it is important to createa safe and comfortable atmosphere. Despite being a space used for a short period oftime, it is important f

Device-measured physical activity and sedentary time are suggested to be more important determinants of all-cause mortality compared to body mass index (BMI) in mainly older adults. However, the joint associations of physical activity and sedentary time with BMI in relation to mortality risk in relatively healthy middle-aged individuals are unclear. We followed 770 adults (56 % women, mean age 55.6 years) from a population-based cohort study for up to 15.3 years. BMI categories were combined with tertiles of total, light, and moderate-to-vigorous physical activity and sedentary time. Cox proportional hazards models estimated hazard ratios (HR) of all-cause mortality with 95% confidence intervals (CI). High total and light intensity physical activity and low sedentary time were associated with a lower risk of mortality in normal weight individuals compared with low active overweight/obese; HR: 0.35 (CI: 0.14, 0.86), HR: 0.33 (CI 0.12, 0.89) and HR: 0.34 (CI: 0.13, 0.92). Among overweight/obese individuals, those who were medium active in light physical activity had a lower mortality risk, HR: 0.36 (CI: 0.15, 0.83), compared with low active. Medium sedentary individuals had a lower risk, HR: 0.43 (CI: 0.20, 0.94) compared with those who were most sedentary. Associations among the most active or least sedentary tertiles were similar irrespective of BMI category. In conclusion, higher physical activity and lower sedentary time were associated with lower mortality risk irrespective of BMI. Physical activity should be promoted and prescribed to individuals with low physical activity levels irrespective of weight status.

ABSTRAK Tujuan penelitian ini adalah untuk menganalisis kontrol dan monitoring arus listrik CCR pada lampu PAPI di Bandar Udara Silangit. Pengumpulan data menggunakan observasi dengan cara pengamatan dan pengukuran. Berdasarkan data yang diperoleh, minimal 2,2 Ampere dan arus maksimum yang dibutuhkan untuk intensitas besar adalah 6,5 Ampere dengan kenaikan arus 5 langkah. Intensitas dan besarnya arus yang didapat memiliki nilai stabil dari hasil perbandingan monitoring dan pengukuran dilapangan pacu bandara. Kata kunci— CCR, Intensitas Cahaya, Landasan Pacu Bandara, Sistem Penerangan ABSTRACT The purpose of this study was to analyze the control and monitoring of CCR electric current on PAPI lamps at Silangit Airport. Data collection uses observation by means of observation and measurement. Based on the data obtained, a minimum of 2.2 Ampere and the maximum current required for large intensity is 6.5 Ampere with a current increase of 5 steps. The intensity and magnitude of the flow obtained have a stable value from the comparison results of monitoring and measurement on the airport runway. Keywords— Airport Runway, CCR, Light Intensity, Lighting System

Wreckfish (Polyprion americanus) is a promising new species for aquaculture diversification due to its fast growth, late reproductive maturation, and high market price. Nowadays, low larval survival is considered the biggest limitation in wreckfish farming. Here, the fertilization, hatching, and survival rates of 20 spawning events from an established wreckfish broodstock have been analyzed in order to characterize the main bottlenecks in wreckfish early and larval development. The ontogenesis of the skeletal system and the incidence of skeletal deformities have been assessed in 632 samples from larval rearing trials using an acid free double staining protocol. Furthermore, the effect of different rearing temperatures (13 vs 16 ºC) and light intensities at water surface (600, 900 and 1200 lux) on the skeletal development have been also explored. Results showed as while a variable egg fertilization rate (61.75 ± 34.62%) were achieved, a very poor hatching (4.52 ± 9.27%) and survival rate (0.01 ± 0.00%) until 71 days post hatching (dph) were observed. Swimbladder inflation was first seen at 7 dph, and at 11 and 25 dph a 61-63% of fish functional swimbladder. The first skeletal structures to be formed were those related with breathing and feeding activities (e.g., cleithrum, Meckel¿s cartilage and ceratobranchials) and were visible in larvae of 4-5 mm of standard length (SL). Ossification of the vertebral column progressed in an anterior-to-posterior direction, being fully ossified at 7-14 mm of SL. Regarding the skeletal deformities, a high incidence (63%) of jaw deformity (particularly lower jaw deformity) was observed in larvae of 4-5 of SL, progressively decreasing (up to 5%) in larvae of >6 mm of SL. Deformed vertebrae (compressed, fused, and/or displaced) were mainly located at the 13 to 15th vertebra, and were associated to lordosis, most probably due to the no swimbladder inflation. No clear relationship between temperature and the incidence of lower jaw deform

This study reports the effect of N2 and CO2 bubbles on dilute to dense gas-liquid two-phase bubbly flow. A shadowgraph imaging technique captured bubble images at a high spatiotemporal resolution. The recordings of bubble images allow us to compute gas fraction distribution. It requires challenging segmentation and gas-liquid interface detection approaches in image processing. Hence a novel gas contour characterization technique has been introduced in this study that analyses light intensity per pixel for quantifying the effect of local gas volume fraction. The dominant gas structure and repetitive gas pattern have also been determined here using Fourier transform-based power spectral density and 2D cross-correlation functions, respectively. Gas-liquid flow regimes of dissolved CO2 bubbles are found quite different than that of N2 bubbles. The plausible reasons are that gas fraction distribution at the sparger region may inhibit bubble coalescence and the positive surface charge of CO2 bubbles acts as a barrier to the interface deformation., Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public., ChemE/Transport Phenomena, ChemE/O&O groep

Growing small seedling tubers from true seed, comparable with mini tubers, in controlled conditions could be a method to multiply healthy starting material of potato. In indoor farming systems, the conditions can be optimised for high production. In field trials, it is impossible to investigate the effects of environmental factors such as temperature and light separately. In this study, we performed three climate room experiments in which the effects of light intensity, temperature and percentage of far-red light in the light spectrum on tuber production were assessed. We found that increasing the average temperature reduced tuber number and tuber weight. Increasing the diurnal temperature variation while keeping the average temperature equal resulted in increased tuber size. The light treatments on the other hand only affected the number of tubers per plant: increasing light intensity and increasing the percentage of far-red light in the spectrum enhanced the number of tubers. Moreover, interaction in tuber production between inbred lines and temperature was significant, with some inbred lines being relatively tolerant to high temperature. These findings will help breed for heat tolerant varieties and optimise growing conditions for tuber production in indoor farming systems.

The article processing charge was funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) – 491192747 and the Open Access Publication Fund of Humboldt-Universität zu Berlin., With the aim of optimizing resources in regional production of nutritive valuable leafy vegetables, this study was conducted to obtain more knowledge regarding the interdependencies between light conditions and accumulation of inorganic constituents. The test plant, P. odorata, was cultivated in a climate chamber with fluorescent tubes as the main light source and daylight integrals (DLI) varying between 4.68 and 9.06 mol·m−2·day−1. The average DLI in greenhouse experiments was 41.55 mol·m−2·day−1. Light conditions were modified using additional LEDs (443, 515, and 629 nm) or by covering the plants with photoselective plastic films, leading to a lower DLI and modified light spectrum, especially by reducing the green spectral range. Contents of nitrate, phosphorus, potassium, magnesium, calcium, and iron, biomass accumulation, and water content were analyzed. In terms of particular light modifications, additional green (515 nm) and red (629 nm) LEDs showed reducing effects on nitrate content at both cultivation locations. Other inorganic constituents were affected differently depending on cultivation location. However, the calculation of average partial correlation coefficients enabled a more general statement. Increasing DLI correlated positively with contents of magnesium, nitrate, and potassium but negatively with contents of calcium and iron. Additionally, nitrate content correlated positively with the spectral range of 651–700 nm but negatively with the R:FR ratio. Consequently, a general recommendation related to the light conditions is not possible, as inorganic constituents were affected differently. Nevertheless, as the nitrate content in leafy vegetables is of high concern and was reduced by higher shares of green or red light, this might be one way to regulate nitrate content in leafy vegetables., Peer Reviewed

Artificial lighting is complementary and single-source lighting for controlled Environment Agriculture (CEA) to increase crop productivity. Installations to control CO2 levels and luminaires with variable spectrum and intensity are becoming increasingly common. In order to see the net assimilation of CO2 based on the relationship between the three factors: intensity, spectrum and CO2 concentration, tests are proposed on tomatoes seedling with combinations of ten spectra (100B, 80B20G, 20B80G, 100G, 80G20R, 20G80R, 100R, 80R20B, 20R80B, 37R36G27B) seven light intensities (30,90, 200, 350, 500, 700 and 1000 mmol·m-2 s-1) and nine CO2 concentrations(200, 300, 400, 500, 600, 700, 800 and 900 ppm). These tomato seedlings grew under uniform conditions with no treatments applied up to the moment of measurement by a differential gas analyzer. We have developed a model to evaluate and determine under what spectrum and intensity of light photosynthesis the Net assimilation of CO2 (An) is more significant in the leaves of tomato plants, considering the CO2 concentration as an independent variable in the model. The evaluation of the model parameters for each spectrum and intensity shows that the intensity has a more decisive influence on the maximum An rate than the spectra. For intensities lower than 350 mmol·m-2 s-1, it is observed that the spectrum has a greater influence on the variable An. The spectra with the best behaviour were 80R20B and 80B20R, which maintained An values between 2 and 4 (mmol CO2·m-2·s-1) above the spectra with the worst behaviour (100G, 80G20R, 20G80R and 37B36G27R) in practically all situations.Photosynthetic Light-Use Efficiency (PLUE) was also higher for the 80B20R and 20R80B spectra with values of 36,07 and 33,84 mmol CO2·mol photon-1,respectively, for light intensities of 200 mmol·m-2 s-1 and 400 ppm of CO2 that increased to values of 49,65 and 48,38 mmol CO2·mol photon-1 for the same light intensity and concentrations of 850 ppm. The choice of s

In this chapter, the method called Firefly Algorithm (FA) is described, including a brief history, the algorithm, and its application to the inverse radiative transfer problem, for the determination of the optical thickness, single scattering albedo, and diffuse reflectivities in the internal part of the boundary surfaces of one-dimensional homogeneous participating media. Two variants of the FA method are also presented: FAEP Firefly with epidemic predation and FAcom Firefly with fuzzy strategy (fuzzy and center of mass). Additionally, the three approaches FA, FAEP, and FAcom are used to obtain estimates for the scattering and absorption coefficients in two-layer one-dimensional heterogeneous participating media., isbn: 978-3-031-43543-0 978-3-031-43544-7, Pages: 157-168

Throughout history, different intraocular illumination methods for vitreoretinal surgery have been used and the most common limitations to the state-of-the-art intraocular illumination methods are the glare and reflections created by the illumination device and the relatively small illuminated area. A way to tackle these limitations could be by using a ring-light configuration, which produces diffuse scattered illumination for a full 360° around the object. In this study, we developed and experimentally evaluated two ring-light configurations for intraocular illumination during vitreoretinal surgery: one for insertion through the pars plana (20 mm), and one for insertion through the cornea and placement in the posterior chamber (11 mm). Both prototypes are made from a 27 gauge Eckardt TwinLight (DORC, the Netherlands), placed inside a capillary tube cut in half through the length. Cuts were made in the fiber every 2 mm, perpendicular to the length of the fiber, to allow light to exit the fiber through the cladding. By measuring the light intensity and illuminated area, we found that the ring-light configurations produce a lower light intensity but also a slightly larger illuminated area and a more diffuse and uniformly distributed illumination than the Eckardt TwinLight. The placement of the ring-light in the posterior chamber proved to be unsafe and complex, since the installation procedure in ex-vivo porcine cadaver eyes could not be executed without damaging the lens bag, lens zonules, posterior iris and cornea, due to the lack of space in the posterior chamber, and the rigidity and sharp tip of the ring. The ring-light configuration that is inserted through the pars plana also caused damage to the retina and lens bag, due to the ring’s rigidity and its sharp tip. However, this configuration shows potential when the ring would be made from a more flexible material and has an incorporated pigtail curve a the distal end, which can be easily achieved, Biomedical Engineering

Agroforestry is an integration of tree species with agricultural crops or livestock that can be directly used to enhance agro biodiversity, rural livelihood and to meet the demand of green fodder throughout the year. Considering this fact, a study was done at Chaudhary Charan Singh Haryana Agricultural University, Hisar, Haryana to assess the productivity of fodder crops under poplar based agroforestry system. In February 2016, poplar was planted in six different spacing of 3× 3 m, 4×3 m, 5×3 m, 6×3 m, 7×3 m and 8×3 m. In this study, fodder crops (sorghum during Kharif season and oat and berseem during Rabi season) were intercropped in different spacing’s of poplar and compared with control in three replications. The results revealed that the maximum DBH (13.92 cm), basal diameter (16.90 cm) and crown spread (6.79 m) attained in 8×3 m spacing while maximum height (9.61 m) is attained in 3×3 m spacing. The highest pH (7.94) and EC (0.27 dS/m) were recorded in 8×3 m spacing while highest SOC (0.47 %), N (158.5 kg/ha), P (16.8 kg/ha) and K (343.8 kg/ha) were recorded in 3×3 m spacing. Green fodder biomass of sorghum (38.45 t/ha), berseem (64.56 t/ha) and oat (52.62 t/ha) was recorded higher in wider spacing (8×3 m) as compared to sole crops. The maximum light intensity (672.4 Lux) was recorded in 8×3 m at 1.00 pm in the month of July, 2018. Higher value of BCR was observed for poplar with oat (2.44) followed by poplar with sorghum (2.31) and poplar with berseem (2.28) under 3×3 m spacing indicating that closer spacing of 3×3 m of poplar is more economic than the other spacings due to more number of trees per unit area and more production of wood.

This paper describes the design of an adaptable, low-cost, and energy efficient gesture detection system. The system leverages the ambient light available in the environment to perform Visible Light Sensing (VLS) using powerful Convolutional Neural Networks. The focus lies on designing a system that is capable of robust gesture detection in any environment while only utilizing a limited number (3) of photodiode sensors. The research conducted in this paper contributes to two crucial aspects of VLS gesture recognition systems. First, it shows how the photodiode sensors can be automatically fine-tuned using four resistors to achieve excellent sensing performance in a wide range of lighting environments from 50 Lux up to 150k Lux. Secondly it is shown that a photodiode arrangement consisting of an equilateral triangle with sides of 5cm facilitates the highest performance and robustness using Dynamic Time Warping for general and user-friendly gestures., CSE3000 Research Project, Gesture Recognition Empowered by Ambient Light and Embedded AIx, Computer Science and Engineering

In the present work, the recurring topic of a point sources of light is extended to spherical sources of light, through a simple experimental setup and the modeling of light intensity as the sum of point sources. The results show that the model remarkably fits to measurements in the near field when we include an angular response function of the light sensor of a smartphone used as a light detector. The response function in the form of a modified cosine turns out to be important for modeling the illuminance in the near field zone. Additionally, far field illuminance measurements are used to determine luminous flux of two spherical sources, LED type, with notably different radii, obtaining discrepancies of less than 3% compared to the nominal values, where the limited opening angle of the light source has been considered., En el presente trabajo se extiende el tópico recurrente de una fuente de luz puntual al de fuentes de luz esféricas, a través de un simple montaje experimental y el modelamiento de la intensidad de luz como suma de fuentes puntuales. Los resultados muestran que el modelo ajusta notablemente a las mediciones en el campo cercano cuando incluimos una función de respuesta angular del sensor de luz de un smartphone usado como detector de luz. La función de respuesta en forma de coseno modificado resulta ser importante para modelar la Iuminancia en la zona de campo cercano. Adicionalmente, las mediciones de Iluminancia en el campo lejano son usadas para determinar el flujo luminoso de dos fuentes esféricas, tipo LED, de radios notablemente diferentes, obteniendo discrepancias menores al 3% comparados con los valores nominales, en donde se ha considerado el ángulo de apertura limitado de la fuente de luz.

Este documento está orientado al mejoramiento de la seguridad vial en el tramo del PR 6+800 AL PR 8+000 apoyado en la Norma ISO 39001 Es la norma con relación directa a la conservación de vidas humanas y nos lleva a adoptar un Sistema de Gestión de la Seguridad Vial esencial para aquellas organizaciones que desempeñan gran parte de su labor en medios de transporte. La norma ISO 39001 recoge los estándares que debe cumplir una empresa para poder adoptar un Sistema de Gestión de la Seguridad Vial (SV), también llamado Road Traffic Security (RTS). Esta es una norma muy necesaria para aquellas organizaciones o empresas que desarrollan su trabajo o parte de él en la carretera.

Both light intensity and spectrum (280–800 nm) affect photosynthesis and, consequently, the formation of reactive oxygen species (ROS) during photosynthetic electron transport. ROS, together with antioxidants, determine the redox environment in tissues and cells, which in turn has a major role in the adjustment of metabolism to changes in environmental conditions. This process is very important since there are great spatial (latitude, altitude) and temporal (daily, seasonal) changes in light conditions which are accompanied by fluctuations in temperature, water supply, and biotic stresses. The blue and red spectral regimens are decisive in the regulation of metabolism because of the absorption maximums of chlorophylls and the sensitivity of photoreceptors. Based on recent publications, photoreceptor-controlled transcription factors such as ELONGATED HYPOCOTYL5 (HY5) and changes in the cellular redox environment may have a major role in the coordinated fine-tuning of metabolic processes during changes in light conditions. This review gives an overview of the current knowledge of the light-associated redox control of basic metabolic pathways (carbon, nitrogen, amino acid, sulphur, lipid, and nucleic acid metabolism), secondary metabolism (terpenoids, flavonoids, and alkaloids), and related molecular mechanisms. Light condition-related reprogramming of metabolism is the basis for proper growth and development of plants; therefore, its better understanding can contribute to more efficient crop production in the future., Version of record

A photon avalanche (PA) effect that occurs in lanthanide-doped solids gives rise to a giant nonlinear response in the luminescence intensity to the excitation light intensity. As a result, much weaker lasers are needed to evoke such PAs than for other nonlinear optical processes. Photon avalanches are mostly restricted to bulk materials and conventionally rely on sophisticated excitation schemes, specific for each individual system. Here we show a universal strategy, based on a migrating photon avalanche (MPA) mechanism, to generate huge optical nonlinearities from various lanthanide emitters located in multilayer core/shell nanostructrues. The core of the MPA nanoparticle, composed of Yb3+ and Pr3+ ions, activates avalanche looping cycles, where PAs are synchronously achieved for both Yb3+ and Pr3+ ions under 852 nm laser excitation. These nanocrystals exhibit a 26th-order nonlinearity and a clear pumping threshold of 60 kW cm−2. In addition, we demonstrate that the avalanching Yb3+ ions can migrate their optical nonlinear response to other emitters (for example, Ho3+ and Tm3+) located in the outer shell layer, resulting in an even higher-order nonlinearity (up to the 46th for Tm3+) due to further cascading multiplicative effects. Our strategy therefore provides a facile route to achieve giant optical nonlinearity in different emitters. Finally, we also demonstrate applicability of MPA emitters to bioimaging, achieving a lateral resolution of ~62 nm using one low-power 852 nm continuous-wave laser beam., QC 20230124

Research shows that university students of Pedagogy in Physical Education present better parameters of physical condition, however, little information is available on sedentary behavior, physical activity (PA) and sleep patterns measured objectively. The objective of this research is to describe sedentary behavior, PA and sleep patterns; determine if there are significant differences between students according to sex and year of admission to university; and determine if there is an association between PA intensity and sleep patterns. We worked with a sample of 128 students, in which sedentary behavior, PA of light, moderate and vigorous intensity, and sleep patterns (sleep time, time in bed and sleep efficiency) were objectively evaluated. The results indicate that first year students present the highest values of average minutes per day for the three PA intensities (men: light = 71.5 min, moderate = 100.4 min, vigorous = 12 min; women: light = 80.3 min, moderate = 93.8 min, vigorous = 6.5 min), in addition to having less sleep time, however, their sleep efficiency is higher. In conclusion, first-year students present less time of sedentary behavior, greater amount of PA in the three intensities and less time of sleep, but greater efficiency. When comparing by sex, women present less PA of moderate and vigorous intensity. Light intensity PA was associated with assessed sleep patterns., Investigaciones demuestran que estudiantes universitarios de Pedagogía en Educación Física presentan mejores parámetros de condición física, sin embargo, es poca la información disponible sobre comportamiento de movimiento de 24 horas, medidas de manera objetiva. El objetivo de la presente investigación es describir conducta sedentaria, AF y patrones de sueño; determinar si existen diferencias significativas entre estudiantes según sexo y año que se encuentran cursando en la universidad; y determinar si existe asociación entre intensidad de AF y patrones de sueño. Se trabajó con una muestra de 128 estudiantes, en los cuales se evaluó de manera objetiva conducta sedentaria, AF de intensidad ligera, moderada y vigorosa, y patrones del sueño (tiempo de sueño, tiempo en cama y eficiencia del sueño). Los resultados indican que los estudiantes de primer año presentan para las tres intensidades de AF, los valores más altos de minutos promedio por día (hombres: ligera= 71.5 min, moderada= 100.4 min, vigorosa= 12 min; mujeres: ligera= 80.3 min, moderada= 93.8 min, vigorosa= 6.5 min), además de presentar menor tiempo de sueño, sin embargo, su eficiencia del sueño es más alta. En conclusión, los estudiantes de primer año presentan menor tiempo de conducta sedentaria, mayor cantidad de AF en las tres intensidades y menor tiempo de sueño, pero mayor eficiencia. Al comparar por sexo, las mujeres presentan menor cantidad de AF de intensidad moderada y vigorosa. AF de intensidad ligera se asoció con los patrones del sueño evaluados.

Thousands of scientific papers have described how plants responded to different levels of a given environmental factor, for a wide variety of physiological processes and morphological, anatomical or chemical characteristics. There is a clear need to summarize this information in a structured and comparable way through meta-analysis. This paper describes how to use relative trait responses from many independent experiments to create generalized dose-response curves. By applying the same methodology to a wide range of plant traits, varying from the molecular to the whole plant level, we can achieve an unprecedented view on the many ways that plants are affected by and acclimate to their environment. We illustrate this approach, which we refer to as ‘MetaPhenomics’, with a variety of previously published and unpublished dose-response curves of the effect of light intensity on 25 plant traits. Furthermore, we discuss the need and difficulties to expand this approach to the transcriptomics and metabolomics level, and show how the generalized dose-response curves can be used to improve simulation models as well as the communication between modelers and experimental plant biologists.

This study assesses the performance of the model-assisted Design of Experiment (mDoE) software toolbox for the design of two microalgae bioprocesses. The mDoE-toolbox was applied to maximize biomass growth for Desmodesmus pseudocommunis in a photobioreactor by varying the light intensity and pH and for Chlorella vulgaris in shake flasks, by varying the light intensity and duration. For both case studies, a mathematical mechanistic model was applied. In the first study only one experiment was necessary to adapt the mathematical model and identify a combination of light intensity and pH that improved biomass yield, as confirmed experimentally. In the second study, no well-established model was available for the specific experimental arrangement. On the basis of the literature, a mathematical model was constructed and a first cycle of mDoE was performed, thus identifying the desired factor combinations. Experiments confirmed the high biomass yield but revealed shortcomings of the model. The model was improved and a second cycle of mDoE was performed. The recommended factor combinations from both cycles were comparable. The mDoE was found to be a time-saving, cost-effective and useful method enabling the identification of factor combinations leading to high biomass production for the design of two different microalgae bioprocesses with low experimental effort.

The effect of light intensity and inoculum volume on the occurrence of photooxidation for Leptolyngbya sp. QUCCCM 56 was investigated, to facilitate the transition from small-scale laboratory experiments to large-scale outdoor cultivation. Indoor, the strain was capable of growing at light intensities of up to 5600 µmol photons/m2/s, at inoculation densities as low as 0.1 g/L (10% inoculation volume vol/vol). Levels of chlorophyll and phycocyanin showed a significant decrease within the first 24 h, indicating some level of photooxidation, however, both were able to recover within 72 h. When cultivated under outdoor conditions in Qatar during summer, with average peak light intensities 1981 ± 41 μmol photons/m2/s, the strain had difficulties growing. The culture recovered after an initial adaptation period, and clear morphological differences were observed, such as an increase in trichome length, as well as coiling of multiple trichomes in tightly packed strands. It was hypothesized that the morphological changes were induced by UV-radiation as an adaptation mechanism for increased self-shading. Furthermore, the presence of contaminating ciliates could have also affected the outdoor culture. Both UV and contaminants are generally not simulated under laboratory environments, causing a mismatch between indoor optimizations and outdoor realizations.

[EN] In order to establish a lighting regime suitable for rabbit farms in East China, the effects of lighting schedule, intensity and colour on the reproductive performance of rabbit does were evaluated by three experiments, respectively. In experiment 1, does were exposed to different lighting schedules: 16L:8D-continuous, 16L:8D-18d (6 d before artificial insemination (AI) to 12 d post-AI), 16L:8D-6d (6 d before AI to the day of AI) and 12L:12D-continuous. In experiment 2, does were exposed to different light intensities: 40 lx, 60 lx, 80 lx and 120 lx. In experiment 3, does were exposed to different light colours: white, yellow, blue and red. For all experiments, conception rate, kindling rate and pre-weaning mortality were calculated; litter size at birth, litter weight at birth, litter size at weaning, litter weight at weaning and individual kit weight at weaning were recorded. Results showed that none of the reproductive parameters of does were affected by the application of 16L:8D-18d lighting schedule compared with the continuous 16L:8D group(P>0.05). Moreover, rabbits does exposed to 80 lx light performed as well as those under 120 lx light in conception rate, kindling rate, litter size (total and alive) at birth and litter weight at birth (P>0.05). Furthermore, the exposures of 60 lx and 80 lx light were beneficial for litter weight at weaning. In addition, red light had a positive effect, as it led to a larger litter size and litter weight at weaning and lower pre-weaning mortality than white light (P<0.05). In summary, a 16L:8D photoperiod with 80 lx red light from 6 d before AI to 12 d post-AI is recommended for use in breeding of rabbit does according to our results.

The objective of this study is to analyze the impact of light intensity on the subjective complaints of librarians and visitiors at an academic library. This research applied both quantitative and qualitative techniques on 696 visitors and librarians. The result suggests that the effects of light intensity include eyestrain, reading difficulty, dizziness, shoulder and back pains, as well as impaired concentration. Also, the frequency of reading and working impacted the subjective complaints. Furthermore, the intensity as well as the frequency of reading and working greatly influenced the subjective complaints. Based on the qualitative analysis, the development of light concepts and room design significantly influenced the comfort level. Therefore, the negative impact of lighting is exacerbated by the increasing frequency of reading and working. However, library room designs greatly contribute to the comfort level of librarians and visitors.

This study aimed to clarify whether the light condition-dependent changes in the redox state and subcellular distribution of glutathione were similar in the dicotyledonous model plant Arabidopsis (wild-type, ascorbate- and glutathione-deficient mutants) and the monocotyledonous crop species wheat (Chinese Spring variety). With increasing light intensity, the amount of its reduced (GSH) and oxidized (GSSG) form and the GSSG/GSH ratio increased in the leaf extracts of both species including all genotypes, while far-red light increased these parameters only in wheat except for GSH in the GSH-deficient Arabidopsis mutant. Based on the expression changes of the glutathione metabolism-related genes, light intensity influences the size and redox state of the glutathione pool at the transcriptional level in wheat but not in Arabidopsis. In line with the results in leaf extracts, a similar inducing effect of both light intensity and far-red light was found on the total glutathione content at the subcellular level in wheat. In contrast to the leaf extracts, the inducing influence of light intensity on glutathione level was only found in the cell compartments of the GSH-deficient Arabidopsis mutant, and far-red light increased it in both mutants. The observed general and genotype-specific, light-dependent changes in the accumulation and subcellular distribution of glutathione participate in adjusting the redox-dependent metabolism to the actual environmental conditions., Version of record

Ostreopsis cf. ovata is a benthic and ovatoxin-producing dinoflagellate proliferating yearly along the Mediterranean coasts where blooms have been related to human illness and unusual mortality of marine organisms. The spreading of O. cf. ovata in this temperate area has been linked to global changes and its consequences such as the increase of temperature or light intensities. In the present study, an experimental design using batch cultures of pre-acclimated cells of a strain of O. cf. ovata isolated from Villefranche-sur-Mer (NW Mediterranean Sea, France), was implemented to investigate the combined effect of temperature (23, 27 and 30 °C) and light intensity (200, 400 and 600 µmol m−2 s−1) on the growth, metabolome and OVTX content. Both light intensity and temperature affected the growth as significantly higher growth rates were obtained under 400 and 600 µmol m−2 s−1 while the maximum values were obtained at 27 °C (0.48 d−1). Metabolomic analyses highlighted a clear effect only for temperature that may correspond to two different strategies of acclimation to suboptimal temperatures. Significant features (such as carotenoid and lipids) modified by the temperature and/or light conditions were annotated. Only temperature induced a significant change of OVTX content with higher values measured at the lowest temperature of 23 °C (29 – 36 pg cell−1). In a context of global changes, these results obtained after acclimation suggest that the increase of temperature might favor the proliferation of less toxic cells. However, in the light of the intraspecific variability of O. cf. ovata, further studies will be necessary to test this hypothesis. This study also highlighted the lack of knowledge about the metabolome composition of such non-model organisms that impairs data interpretation. There is a need to study more deeply the metabolome of toxic dinoflagellates to better understand how they can acclimate to a changing environment.

Concepts of semi-closed greenhouses can be used to save energy, whereas their technical equipment often causes a decrease in the light received by the plants. Nevertheless, higher yields are achieved, which are presumably triggered by a higher CO2 concentration in the greenhouse and associated higher photosynthesis because of the technical cooling and the longer period of closed ventilation. Therefore, we examined the effects of photosynthetic photon flux density (PPFD) and CO2 concentration on plant photosynthesis and transpiration in tomato using a multiple cuvette gas exchange system. In a growth chamber experiment, we demonstrated that a light-mediated reduction in photosynthesis can be compensated or even overcompensated for by rising CO2 concentration. Increasing the CO2 concentration from 400 to 1000 µmol mol−1 within the PPFD range from 303 to 653 µmol m−2 s−1 resulted in an increase in net photosynthesis of 51%, a decrease in transpiration of 5 to 8%, and an increase in photosynthetic water use efficiency of 60%. Estimations showed that light reductions of 10% can be compensated for via increasing the CO2 concentration by about 100 µmol mol−1 and overcompensated for by about 40% if CO2 concentration is kept at 1000 instead of 400 µmol mol−1., Peer Reviewed

In this paper, we investigate the given ambient lighting conditions in today’s schools. On the example of Oulu University Teacher Training School, the classroom quality in terms of the available amount of ambient lighting is analysed. In particular, attention is paid to the available illuminance of the pupils’ desks. Commonly, light is produced artificially by light sources installed on the classroom’s ceiling and obtained from the outside through windows. However, due to the use of digital blackboards, window blinds are often closed and lights are often switched off, thereby, reducing the available light in the classroom significantly. Furthermore, our results reveal that each pupil’s desk receives a different light intensity. It is worth noting that low levels of ambient lighting can result into a degradation of learning performances and, therefore, requiring pupils more time solve different types of activities assigned by the teacher.

Introduction: Solar energy technology, a natural and free energy source, is implemented in places with limited access to traditional electric power, in some cases in the agricultural field or small rural human settlements. Currently, commercial systems include a charge control unit with a small display, to show the voltage generated, but unfortunately, the operator must go to the controller to check its performance, so it is necessary to have a tool that allows knowing the energy conversion in real-time remotely. This can be achieved by making use of the Internet of Things (IoT) technology. Currently, there are several IoT platforms; some are free, others are demo or paid versions. Method: In this work, a prototype was developed with a system for monitoring the voltage and light intensity of a small solar cell and a TSL2561 digital sensor. The Arduino programming environment coupled to a myDevices Cayenne (IoT) platform was used to transmit and access the data remotely. Results: With the integration of the components, the myDevices Cayenne platform was able to monitor in real-time the voltage of the solar cell and the luminous intensity of the environment visually and intuitively, from any computer or cell phone with internet access. Discussion or Conclusion: The myDevices Cayenne IoT platform has become an attractive, accessible, robust, and easy-to-use option for the development of innovative IoT projects applied to different sectors of economic importance., Resumen: Introducción: La tecnología de energía solar, fuente de energía natural y gratuita, es implementada en lugares con acceso limitado a la energía eléctrica tradicional, en algunos casos en el ámbito agrícola o en pequeños asentamientos humanos rurales. Actualmente, los sistemas comerciales, incluyen una unidad de control de carga con una pequeña pantalla, con la finalidad de mostrar el voltaje generado, pero desafortunadamente el operario debe de acudir hasta el controlador para revisar su desempeño, por lo que es necesario tener una herramienta que permita conocer la conversión energética en tiempo real de manera remota. Esto se puede lograr haciendo uso de la tecnología del internet de las cosas (IoT). En la actualidad existen diversas plataformas IoT; algunas son gratuitas, otras son versiones demostrativas o de paga. Método: En el presente trabajo se desarrolló un prototipo con un sistema de monitoreo de voltaje e intensidad luminosa de una pequeña celda solar y un sensor digital TSL2561. Se utilizó el entorno de programación de Arduino acoplado a una plataforma (IoT) myDevices Cayenne para poder transmitir y acceder a los datos de manera remota. Resultados: Con la integración de los componentes se logró monitorear en la plataforma myDevices Cayenne en tiempo real el voltaje de la celda solar y la intensidad luminosa del entorno de una manera visual e intuitiva, desde cualquier computadora o teléfono celular con acceso a internet. Discusión o Conclusión: La plataforma de IoT myDevices Cayenne se convierte en una opción atractiva, accesible, robusta y fácil de usar en el desarrollo de proyectos novedosos con IoT aplicados a diferentes sectores de importancia económica.

Generalised dose–response curves are essential to understand how plants acclimate to atmospheric CO2. We carried out a meta-analysis of 630 experiments in which C3 plants were experimentally grown at different [CO2] under relatively benign conditions, and derived dose–response curves for 85 phenotypic traits. These curves were characterised by form, plasticity, consistency and reliability. Considered over a range of 200–1200 µmol mol−1 CO2, some traits more than doubled (e.g. area-based photosynthesis; intrinsic water-use efficiency), whereas others more than halved (area-based transpiration). At current atmospheric [CO2], 64% of the total stimulation in biomass over the 200–1200 µmol mol−1 range has already been realised. We also mapped the trait responses of plants to [CO2] against those we have quantified before for light intensity. For most traits, CO2 and light responses were of similar direction. However, some traits (such as reproductive effort) only responded to light, others (such as plant height) only to [CO2], and some traits (such as area-based transpiration) responded in opposite directions. This synthesis provides a comprehensive picture of plant responses to [CO2] at different integration levels and offers the quantitative dose–response curves that can be used to improve global change simulation models., Peer Reviewed

Since the outbreak of SARS-COV-2, various virus inactivation techniques have been applied to suppress the spread of virus. Ultraviolet exposure inactivation is an efficient approach to inactivate virus, within UV band, UV-C with comparatively higher energy. UV-C has been proved to inactivate viruses efficiently, while to figure out efficient inactivation approach, virus reduction rate as a function of UV-C wavelength with different viral sensitivity and quantitative exposure dose should be measured through experiments. On the one hand, miniatured, energy-efficient and fully-customized UV-C light-emitting diodes (LED) offer possibility of switching wavelengths and adjusting quantitative optical properties, on the other hand, UV-C LEDs have been produced with the latest technology based on Aluminium gallium nitride (AlGaN). ~\\Multifunctional UV-C LED Virus Inactivation Experimental Platform is a system designed with replaceable UV-C wavelengths, controllable light intensity and exposure time for quantitative virology experiments. The system has an initial design for standard virology experimental equipment which offers a new and consistent tool for virus researchers. The Inactivation Platform has been assembled and utilized to perform several Influenza A (ssRNA virus) inactivation experiments in order to obtain reduction rate as a function of UV-C wavelength and exposure dose with Germicidal Curve and Inactivation Curve respectively. ~\\After inactivation experiments implementation and result analysis, the inactivation mechanism on the basis of molecular dynamic research theory and simulation is supposed to be figured out. Due to the complexity of proteins in virus, the research focuses on Nucleic Acid Bases (NABs) as target genetic viral material. The absorbed ultraviolet energy results in ultrafast decay, including molecular electronic transition, virus structure variation (Dimerization) theoretically. The absorbed energy along the band is rev, Electrical Engineering | Embedded Systems

Mariculture wastewater generated from the mariculture industry has increased public concern due to its impact on the sustainability of aquatic environments and aquaculture practices. Herein, the Bacterial-Algal Coupling System was applied for mariculture wastewater treatment. Microalgae growth in heterotrophy and mixotrophy (2000–8000 lux) were first compared. The best microalgal growth and nutrient removal were obtained at 5000 lux, where biomass productivity of microalgae was 0.465 g L−1 d−1, and 98.1% of chemical oxygen demand, 70.7% of ammonia-nitrogen, and 90.0% of total phosphorus were removed. To further understand the nutrient removal through microalgae cultivation, the enzyme activities involved in the Calvin cycle and the Tricarboxylic Acid cycle at different light intensities were determined. Under mixotrophic cultivation, there was a coordination between photosynthesis and heterotrophic metabolism in agal cells, which resulted in a high algal biomass production and removal efficiency of nutrients. This study provided a novel insight into the bioremediation of mariculture wastewater and microalgae cultivation.

Currently, there is a demand for more energy-efficient lighting sources, however, light emitted by different lighting systems differs in primary properties such as intensity, propagation direction, and wavelength spectrum, among others, and these properties may affect insect light attraction. Despite the energetic benefits of light-emitting diodes (LED) as street light systems, their ecological impacts on insects have not yet been tested on a wide range of taxa. Using an experimental approach, we showed that LED street lights lead to a reduction in the total number of insects captured with light traps in a wide range of families. Coleoptera and Lepidoptera orders were the most sensitive groups to ecological light pollution in the study area. We suggest that LED was the least attractive light system for most of the affected groups both because of its very little emitted short-wavelength light and because of its lower light intensity. We expect that the more and more widespread use of LED lights as a measure to reduce economic costs of outdoor lighting should lead to a lower attraction to street lights in most of the affected insect taxa and to diminish the negative impacts of artificial light attraction on the ecosystems.

The use of microbial inoculants, particularly arbuscular mycorrhizal fungi, has great potential for sustainable crop management, which aims to reduce the use of chemical fertilizers and pesticides. However, one of the major challenges of their use in agriculture is the variability of the inoculation effects in the field, partly because of the varying environmental conditions. Light intensity and quality affect plant growth and defense, but little is known about their impacts on the benefits of mycorrhizal symbioses. We tested the effects of five different light intensities on plant nutrition and resistance to the necrotrophic foliar pathogen Botrytis cinerea in mycorrhizal and non-mycorrhizal lettuce plants. Our results evidence that mycorrhiza establishment is strongly influenced by light intensity, both regarding the extension of root colonization and the abundance of fungal vesicles within the roots. Light intensity also had significant effects on plant growth, nutrient content, and resistance to the pathogen. The effect of the mycorrhizal symbiosis on plant growth and nutrient content depended on the light intensity, and mycorrhiza efficiently reduced disease incidence and severity under all light intensities. Thus, mycorrhiza-induced resistance can be uncoupled from mycorrhizal effects on plant nutrition. Therefore, mycorrhizal symbioses can be beneficial by providing biotic stress protection even in the absence of nutritional or growth benefits.

This study was undertaken to fabricate Vertical Farming Structures (VFS) suitable for homestead and evaluate the performance of fabricated vertical farming structures. The experiment was conducted in Kelappaji College of Agricultural Engineering and Technology (KCAET), Tavanur, in Malappuram district, Kerala. Two vertical farming structures DVFS 1 (Developed vertical farming structure 1) and DVFS 2 (Developed vertical farming structure 2) were designed and fabricated. The drip irrigation system was adopted to irrigate the plants to reduce the wastage of water. Amaranthus seedlings of variety ‘Kannara local’ was taken for the trial. Climatic parameters and biometric observations were analyzed to compare and evaluate the performances of vertical farming structures. Correlation analysis was done using IBM SPSS statistics 25 software. The analysis of trials revealed that DVFS 1 showed better performance in every aspect compared to DVFS 2. The biometric observations like plant height and number of leaves were more in T1 at the right side and followed by T3 at the right side of DVFS 1. The plant characteristics are highly correlated with the light intensity. This was the reason for more growth was observed on the right side of DVFS 1. The maximum yield was obtained from the DVFS 1 (58%) than DVFS 2 (42%). The study recommended that usage of the platform like structure with triangular cross-section was more advantageous than the structure with tiers one over the other with Poly Vinyl Chloride (PVC) splits.

Factory produced chicken meat has the lowest climate impact and domesticated poultry, (Gallus gallus), is the world's most commonly bred animal. In Sweden the production of poultry is increasing, also the size of an average facility with chickens is increasing. Vision is their dominant sense organ and the vision is important for the animals to be able to explore their environment and search for food. In this study the aim was to find both an optimal light intensity and the minimum light intensity for increased animal welfare and what's required by regulations for the facilities that keep production hens. The methods involved both a literature study and interviews. Information was also collected from the county administrative boards and the Swedish Board of Agriculture. Results showed that an optimal light intensity could not be established due to lack of research of the fields. Also, optimal light intensity can vary depending on age, hybrids and how prone to hacking a hybrid is, time of day and with what behavior the hen displays. A minimum light intensity of at least 5 lux could be set for hens ́ ability to recognize their environment and for the ability to implement inspections of the hens. Further investigations are needed to examine whether it may be relevant with a higher minimum light level than 5 lux. There should also be more research about optimal light intensity and new regulations according to a minimum light intensity for production hens to improve and secure their welfare and to improve animal health inspections., Kycklingkött är det kött med minst klimatpåverkan och fjäderfän, Gallus gallus, är den djurart som det föds upp flest av i världen. I Sverige ökar antalet fjäderfä samtidigt som den genomsnittliga besättningsstorleken ökar. Det är mer väsentligt än någonsin att hönsen som vi använder inom livsmedelsproduktionen mår bra och har en hög djurvälfärd. Synen är det sinnet som fåglarna använder mest och är viktig för att de ska kunna utföra basala behov som att utforska sin miljö och söka efter föda. Syftet med studien var att ta reda på vilken den optimala belysningsstyrkan är, om en lägsta gräns för belysningsstyrkan kan detekteras utifrån gällande reglering och om det finns ett behov att reglera en miniminivå för belysningsstyrkan, i anläggningar för produktionshöns. Resultatet visade att ingen optimal belysningsstyrka för produktionshöns i dagsläget kan fastställas, varken genom sammanställning av vetenskapliga studier eller genom intervjuer med en expert från SLU, och branschorganisationerna Svensk Fågel och Svenska Ägg. Anledningen är att det inte finns tillräckligt med forskning på optimala belysningsstyrkor för höns och att den optimala belysningsstyrkan kan variera beroende på hönsens ålder, hybrid och hur hackningsbenägen den hybriden är, tid på dygnet och med vilket beteende hönan ska utföra. Hackning och kannibalism är vanliga problem i fjäderfäbesättningar och är en anledning till en låg belysningsstyrka i fjäderfäbesättningar, vilket sänker hönsens aktivitet. Resultatet visade också att det finns flera vetenskapliga belägg för att ett en lägsta gräns av belysningsstyrkan ska kunna fastställas med 5 lux. En miniminivå av belysningsstyrkan kan säkerhetsställa att hönsens syn utvecklas korrekt och att de kan utföra sina naturliga beteenden. 5 lux behövs för att hönsen ska ha möjlighet till att uppfatta sin miljö och för att kontroller av hönsen ska kunna genomföras, vilket krävs av gällande lagstiftning. Men vi anser att det behövs utredas om det kan vara aktuel

Leptolyngbya sp. QUCCCM 56 was investigated as a possible alternative to A. platensis, for the production of phycocyanin-rich biomass under desert conditions. Under elevated temperatures and light intensities, of up to 40 °C and 1800 μmol·m−2·s−1, the strain's biomass productivity was up to 45% higher as compared to reported productivities for A. platensis, with comparable phycocyanin content. Increasing temperatures were found to improve the biomass productivity and phycocyanin content, which, at 40 °C, were 1.09 ± 0.03 gX·L−1·d−1 and 72.12 ± 3.52 mgPC·gX −1, respectively. The optimum biomass productivity was found at a light intensity of 300 μmol·m−2·s−1, with higher light intensities causing a decrease of 15%. Furthermore, of the various phycocyanin extraction methods tested, bead-beating in phosphate buffer had the highest combined phycocyanin yield (169.9 ± 3.6 mgPC·gX) and purity (7.37 ± 0.16) for Leptolyngbya sp. For A. platensis, this extraction method also resulted in the highest extract purities (3.78 ± 0.04). The extract purities obtained for Leptolyngbya sp. are considerably higher than other reported phycocyanin purities, and further investigation is recommended to study the scale-up of both Leptolyngbya sp. and bead-beating for commercial scale high-grade phycocyanin production under desert conditions.

Polar microalgae that are highly productive in cold climates can produce large amounts of biomass and polyunsaturated fatty acids (PUFA). The polar Chlamydomonas malina RCC2488, grows at low temperatures and produces high amounts of lipids, which are mainly composed of PUFA. However, not much is known about its phylogenetic relationship with other strains within the order Chlamydomonadales and the optimum growth conditions for maximum biomass productivity have not yet been identified. In this study, a phylogenetic analysis was performed to determine the closest relatives of C. malina within the Chlamydomonadales order. To select the best growth conditions for maximum biomass productivities in cultivations performed at 8 °C, different salinities (0–80) and light intensities (70–500 μmol photons m−2 s−1) were tested, using bubble column and flat-panel photobioreactors. The effect of nitrogen limitation was tested to determine if C. malina can accumulate energy reserve metabolites (carbohydrates and lipids). Phylogenetic analysis confirmed that C. malina, which belongs to the Chlamydomonales order, is closely related to the psychrophilics Chlamydomonas sp. UWO 241 and Chlamydomonas sp. SAG 75.94, as well as to the mesophilic C. parkeae MBIC 10599. The highest biomass (527 mg L−1 day−1), lipid (161.3 mg L−1 day−1) and polyunsaturated fatty acids (PUFA; 85.4 mg L−1 day−1) productivities were obtained at a salinity of 17.5, light intensity of 250 μmol photons m−2 s−1 and nitrogen replete conditions. Strikingly, the marine C. malina can grow even in fresh water, but the biomass productivity was reduced. While the intracellular lipid content remained unchanged under nitrogen deprivation, the carbohydrate content increased (up to 49.5% w/w), and the protein content decreased. The algal lipids were mainly comprised of neutral lipids, which were primarily composed o

Twelve microalgae species isolated in tropical lagoons of New Caledonia were screened as a new source of antioxidants. Microalgae were cultivated at two light intensities to investigate their influence on antioxidant capacity. To assess antioxidant property of microalgae extracts, four assays with different modes of action were used: 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2’-azinobis (3-éthylbenzothiazoline-6-sulphonique) (ABTS), oxygen radical absorbance capacity (ORAC), and thiobabituric acid reactive substances (TBARS). This screening was coupled to pigment analysis to link antioxidant activity and carotenoid content. The results showed that none of the microalgae studied can scavenge DPPH and ABTS radicals, but Chaetoceros sp., Nephroselmis sp., and Nitzschia A sp. have the capacity to scavenge peroxyl radical (ORAC) and Tetraselmis sp., Nitzschia A sp., and Nephroselmis sp. can inhibit lipid peroxidation (TBARS). Carotenoid composition is typical of the studied microalgae and highlight the siphonaxanthin, detected in Nephroselmis sp., as a pigment of interest. It was found that xanthophylls were the major contributors to the peroxyl radical scavenging capacity measured with ORAC assay, but there was no link between carotenoids and inhibition of lipid peroxidation measured with TBARS assay. In addition, the results showed that light intensity has a strong influence on antioxidant capacity of microalgae: Overall, antioxidant activities measured with ORAC assay are better in high light intensity whereas antioxidant activities measured with TBARS assay are better in low light intensity. It suggests that different antioxidant compounds production is related to light intensity.

Background Cultivation of microalgae in wastewater could significantly contribute to wastewater treatment, biodiesel production, and thus the transition to renewable energy. However, more information on effects of environmental factors, including light intensity, on their growth and composition (particularly fatty acid contents) is required. Therefore, we investigated the biomass and fatty acid production of four microalgal species, isolated in the Northern hemisphere and grown at three light intensities (50, 150 and 300 mu E m(-2) s(-1)). Results Increases in light intensities resulted in higher biomass of all four species and, importantly, raised fatty acid contents of both Desmodesmus sp. and Scenedesmus obliquus. Fourier-transform IR spectrometry analysis showed that the increases in fatty acid content were associated with reductions in protein, but not carbohydrate, contents. Assessment of fatty acid composition revealed that increasing light intensity led to higher and lower contents of oleic (18:1) and linolenic (18:3) acids, respectively. The microalgae consumed more than 75% of the nitrogen and phosphorus present in the wastewater used as growth medium. Conclusion The results show the importance of optimizing light intensities to improve fatty acid production by microalgae and their quality as sources of biodiesel. In addition, increase in fatty acid content is associated with decrease in protein content.

House flies (Musca domestica L.) are common synanthropic pests associated with confined animal operations, including dairy farms. House flies can cause substantial nuisance and may transmit human and animal pathogens. Surprisingly little is known about the daily flight activity of house flies. This study examined diurnal house fly flight activity on two southern California dairies using clear sticky traps to capture flies over hourly intervals. Flight activity for both males and females combined started near dawn and generally increased to a single broad activity peak during mid to late morning. Male flight activity peaked earlier than female flight activity and this separation in peak activity widened as mean daytime temperature increased. Flight activity for both sexes increased rapidly during early morning in response to the combined effects of increasing light intensity and temperature, with decreasing flight activity late in the day as temperature decreased. During midday, flight activity was slightly negatively associated with light intensity and temperature. Collection period (time of day) was a useful predictor of house fly activity on southern California dairies and the diurnal pattern of flight activity should be considered when developing house fly monitoring and control programs.

Flying safely and avoiding obstacles in low light is crucial for the bumblebees that forage around dawn and dusk. Previous work has shown that bumblebees overcome the limitations of their visual system-typically adapted for bright sunlight-by increasing the time over which they sample photons. While this improves visual sensitivity, it decreases their capacity to resolve fast motion. This study investigates what effect this has on obstacle avoidance in flight, a task that requires the bees to reliably detect obstacles in the frontal visual field and to make a timely diversion to their flight path. In both bright and dim light, bumblebees avoided the 5 cm diameter obstacle at a consistent distance (22 cm) although in dim light they approached it more slowly from a distance of at least at least 80 cm. This suggests that bumblebees have an effective strategy for avoiding obstacles in all light conditions under which they are naturally active, and it is hypothesised that this is based on a time-to-contact prediction.

The shade of the trees projected on the herbaceous stratum that grows under the canopy represents an undesired effect for livestock farmers for forage production in the silvopastoral system. In order to determinethe dry matter production and the floristic composition of the herbaceous stratum with different amounts of photosynthetically active radiation, three plots with low tree density (BDA; 50 to 200), moderate tree density (MDA; 201 to 350) and high tree density (ADA; 350 to 500) trees ha-1were selected. In each plot, photosynthetically active radiation (RFA) that affects the herbaceous stratum was estimated and the dry matter production (DM) of the forage herbaceous plants present during 15 weeks of the rainy season was determined. The intensity of light under the canopy and the production of herbaceous forage biomass in BDA, MDA and ADA were 8 594, 6 437 and 3 801 MJ m2year-1and 2 859, 1 988 and 1 679 kg of DM ha-1, respectively. The number of herbaceous species in BDA, MDA and ADA was 38, 48 and 27, respectively, although the dominant species, with more than 80% of the botanical composition, were only six. It is concluded that the tree density modifies the amount of light that falls on the herbaceous stratum, affecting the biomass production and the floristic composition of forage herbaceous plants that grow under the tree canopy in a traditional silvopastoral system in the Low Deciduous Forest., La sombra de los árboles proyectada sobre el estrato herbáceo que crece bajo el dosel representa para los ganaderos un efecto no deseado para la producción de forrajes en el sistema silvopastoril. Con el objetivo de determinar la producción de materia seca y la composición florística del estrato herbáceo con diferente cantidad de radiación fotosintéticamente activa, se seleccionaron tres parcelas con baja densidad arbórea (BDA; 50 a 200), moderada densidad arbórea (MDA; 201 a 350) y alta densidad arbórea (ADA; 350 a 500) árboles ha-1. En cada parcela se estimó la radiación fotosintéticamente activa (RFA) que incide en el estrato herbáceo y se determinó la producción de materia seca (MS) de las herbáceas forrajeras presentes durante 15 semanas de la estación lluviosa. La intensidad de luz bajo el dosel y la producción de biomasa forrajera herbácea en BDA, MDA y ADA fue 8 594, 6 437 y 3 801 MJ m2 año-1 y 2 859, 1 988 y 1 679 kg de MS ha-1, respectivamente. El número de especies herbáceas en BDA, MDA y ADA fue 38, 48 y 27, respectivamente, aunque las especies dominantes, con más de 80% de la composición botánica, fueron solo seis. Se concluye que la densidad arbórea modifica la cantidad de luz que incide en el estrato herbáceo, afectando la producción de biomasa y la composición florística de las herbáceas forrajeras que crecen bajo el dosel arbóreo en un sistema silvopastoril tradicional en la selva baja caducifolia.

Nowadays, the use of halogen or light emission diode (LED) devices in dental attention is constant for almost any oral treatment. The need of providing an adequate light intensity for a correct photopolymerization of the resinous materials is critical. Likewise, it is important to consider the biosecurity norms for avoiding cross-contamination by residues likely to be accumulated at the top of the light guide in contact with oral cavity fluids. Therefore, the use of translucid barriers at the top of the light guide is imperative to protect the health of the patient while providing a correct polymerization of the resinous materials. The present study analyzes the effect of using four translucid barriers in the light intensity of three dental lamps commercially available. The tested barriers are two of commercial availability, and two conventional plastic wraps. Results indicate a significant reduction of light intensity without affecting the requirements for a correct photopolymerization with any barrier. Differences among barriers points out a conventional plastic wrap as more suitable than commercially available barriers, considering only light intensity provided. Keywords: Light intensity; Sleeves; Light curing; Barriers

Kelp life-cycle transitions are complex and susceptible to various (a)biotic controls. Understanding the microscopic part of the kelp's lifecycle is of key importance, as gametophytes form a critical phase influencing, among others, the distributional limits of the species. Many environmental controls have been identified that affect kelp gametogenesis, whose interactive effects can be subtle and counterintuitive. Here we performed a fully factorial experiment on the (interactive) influences of light intensity, light quality, and the Initial Gametophyte Density (IGD) on Saccharina latissima reproduction and vegetative growth of delayed gametophytes. A total of 144 cultures were followed over a period of 21 d. The IGD was a key determinant for reproductive success, with increased IGDs (≥0.04 mg DW · mL−1) practically halting reproduction. Interestingly, the effects of IGDs were not affected by nutrient availability, suggesting a resource-independent effect of density on reproduction. The Photosynthetically Usable Radiation (PUR), overarching the quantitative contribution of both light intensity and light quality, correlated with both reproduction and vegetative growth. The PUR furthermore specifies that the contribution of light quality, as a lifecycle control, is a matter of absorbed photon flux instead of color signaling. We hypothesize that (i) the number of photons absorbed, independent of their specific wavelength, and (ii) IGD interactions, independent of nutrient availability, are major determinants of reproduction in S. latissima gametophytes. These insights help understand kelp gametophyte development and dispersal under natural conditions, while also aiding the control of in vitro gametophyte cultures.

Pleioblastus pygmaeus (Miq.) Nakai, as a dwarf bamboo, providing a high ornamental value in landscaping. Furthermore its well-developed and intricate root system lends its use for soil consolidation and slope protection. A pot experiment was performed to study the impact of different light intensity on the growth characteristics of P. pygmaeus seedlings. The light intensity was controlled by punching circular holes with different diameters in center of the plates cover the pots. The illuminance percentages of the pore diameter area to the inner diameter area of the pot in each treatment were 1.29% (A), 5.16% (B), 11.62% (C), 20.66% (D), 32.28% (E), and 100% (F). The average illumination intensity under treatment A, B, C, D and E is 3.87%, 11.25%, 20.25%, 38.76% and 60.70% of control F (100% of full sunlight), respectively. The results showed that the light intensity is a key factor influencing P. pygmaeus seedlings’ growth and mortality. Seedlings died when light is lower than 38.76%. As light intensity decreased, the mortality increased and the number of culms and total rhizomes, leaf-, aboveground- and underground-biomass significantly decreased, and the gap between the treatments and control significantly increased over the nine month growing period. The generalized additive model (GAM) explained the influence of illuminance and investigation time and indicated a lower determination coefficient on culm height, culm diameter, total rhizome length and total rhizome diameter compared with number of culms, number of total rhizomes and biomass. The diameter of culms showed a decreasing trend during the experiment while their lengths increased even under A treatment (3.87% of full sunlight), suggesting that nonstructural carbohydrates stored prior to the experiment was used for culm height growth under light/carbon limitation. In the case of the leaves, their growth was significantly inhibited under low light intensity (3.87–60.70% of full sunlight) as they are the

Manganese (Mn) plays an important role in the oxygen-evolving complex, where energy from light absorption is used for water splitting. Although changes in light intensity and Mn status can interfere with the functionality of the photosynthetic apparatus, the interaction between these two factors and the underlying mechanisms remain largely unknown. Here, maize seedlings were grown hydroponically and exposed to two different light intensities under Mn-sufficient or -deficient conditions. No visual Mn deficiency symptoms appeared even though the foliar Mn concentration in the Mn-deficient treatments was reduced to 2 mu g g(-1). However, the maximum quantum yield efficiency of PSII and the net photosynthetic rate declined significantly, indicating latent Mn deficiency. The reduction in photosynthetic performance by Mn depletion was further aggravated when plants were exposed to high light intensity. Integrated transcriptomic and proteomic analyses showed that a considerable number of genes encoding proteins in the photosynthetic apparatus were only suppressed by a combination of Mn deficiency and high light, thus indicating interactions between changes in Mn nutritional status and light intensity. We conclude that high light intensity aggravates latent Mn deficiency in maize by interfering with the abundance of PSII proteins.

The external and internal quality of citrus fruit determines consumer acceptance, thereby driving the consumption and demand for fresh fruit. Emphasis is placed on producing a high volume of fruit of good quality, and it is known that light intensity is especially important in influencing sugar content, rind color, and blemish incidence. Extreme environmental conditions are challenging controllable factors. Therefore shade netting is used especially on fruit crops for protection against dramatic climatic events that affect the appearance of the fruit, i.e., excess sunlight, wind, and hail. The study was conducted on 'Nadorcott' mandarin trees planted in 2012 in a commercial orchard in Citrusdal, Western Cape province, South Africa. The aim of this study was to determine the influence of 20% white shade nets on the quality of 'Nadorcott' mandarin fruit. Monthly evaluation of fruit size, rind color, internal quality parameters (°Brix/citric acid ratio) and the incidence of sunburn was performed. The fruit diameter was not influenced by shade net in 2016; however, in 2017 a larger fruit diameter was measured for shade net fruit. Rind color development and internal quality were not influenced negatively by the treatment. Shade net was effective, reducing the incidence of sunburn significantly in both seasons, 2016 and 2017. Moreover, postharvest fruit quality was not negatively affected by the shade net treatments. In summary, our results indicate that shade-netting is a potential preventative technology ensuring unblemished and high quality in 'Nadorcott' mandarins, but further studies are required to evaluate the influence of tree age and microclimatic effect on fruit production and postharvest storage behavior in other citrus cultivars.

Conventional light intensity sensing devices such as a light meter are big in size and incapable of outputting a digitized signal to a microprocessor for further control and actuation. Sensor transducers based on CMOS has therefore increased in popularity. Using CMOS technology, manufacturing costs and the power consumption can be reduced with smaller form factor. This paper presents a proposed design of light sensor for the detection of light intensity. The project utilizes Silterra’s 130 nm CMOS architecture to create a low power and low space monolithic light sensor chip that is able to detect the intensity of light to assist in achieving the recommended levels of light intensity in domestic areas. The light intensity was simulated with a photocurrent and the photodiode operates optimally at a wavelength of 555 nm, the spectral sensitivity of the human eye and has good linearity. The light intensity detected is shown in illuminance (lux) and this project is capable to detect illuminance in the range of 0 to 200 lux with a resolution of 20 lux. The monolithic chip of the light intensity sensor comprises of the transimpedance amplifier which acts as a current to voltage converter and an ADC to convert the analog voltage into a digital reading.  Hence, the output of the light intensity sensor is in binary representation.  The total power consumption of the monolithic light intensity sensor is 1.88mW and the total size of the design is 0.01202 mm2.

The study of the relationship between cultivated plants and environmental factors can provide information ranging from a deeper understanding of the plant biological system to the development of more effective management strategies for improving yield, quality, and sustainability of the produce. In this article, we present a comprehensive metabolomics dataset of two phytochemically divergent lettuce (Lactuca sativa L.) butterhead varieties under different growing conditions. Plants were cultivated in hydroponics in a growth chamber with ambient control. The pre-harvest factors that were independently investigated were light intensity (two levels), the ionic strength of the nutrient solutions (three levels), and the molar ratio of three macroelements (K, Mg, and Ca) in the nutrient solution (three levels). We used an untargeted, mass-spectrometry-based approach to characterize the metabolomics profiles of leaves harvested 19 days after transplant. The data revealed the ample impact on both primary and secondary metabolism and its range of variation. Moreover, our dataset is useful for uncovering the complex effects of the genotype, the environmental factor(s), and their interaction, which may deserve further investigation.