Amount Of Sunlight Research Articles

Chemical composition of ripe fruits of Rubus chamaemorus L. grown in different habitats

Cloudberry (Rubus chamaemorus L.) is one of the most valuable berry-producing plants because of its nutritional properties. The chemical composition and crop yield of ripe fruits of cloudberry grown wild in 10 habitats in northern Finland was analysed over two consecutive summers. For comparison, two clones of cultivated cloudberries were studied as well. The concentrations of citric and malic acids, α-tocopherol, anthocyanins and β-carotene had notable variations between habitats. In particularly, cloudberries grown on open habitats had higher content of citric acid and less α-tocopherol compared to those grown on shaded sites. In a colder and rainy summer the content of anthocyanins and the unsaturation level of fatty acids were significantly higher than in a warmer and drier summer. Crop yields were higher in the warmer summer, except in open sites where yields were quite equal. Cloudberries grown in open habitats showed notable differences in chemical composition when compared to those grown on shaded sites. Results suggest that the amount of sunlight and temperature levels could be the main factors affecting crop yield and chemical composition of cloudberry. In addition, the amount of rainfall may have an effect on anthocyanin concentrations.

Monitoring and maintaining the water clarity of salinity gradient solar ponds

A common problem encountered in salinity-gradient solar ponds is the growth of various types of algae and bacterial populations, which affects the brine clarity and hence reduces thermal performance. Algae and bacterial populations are enhanced by the presence of organic nutrient such as nitrogen and phosphorus. A comprehensive study was undertaken on three salinity-gradient solar ponds in Australia: a 3000 m2 sodium chloride solar pond at Pyramid Hill in Northern Victoria; a 50 m2 sodium chloride; and 15 m2 magnesium chloride solar pond at RMIT University in Bundoora, Victoria. The experimental study involved monitoring the clarity of these three ponds and testing chemical and biological treatment methods to see their effect on the brine transparency. The sources of turbidity and their impacts on clarity and efficiency of salinity-gradient solar ponds are presented in detail in this paper. The initial observation showed that the amount of sunlight is reduced due to the heavy algal growth creating instability in the solar pond as it absorbs light. Two treatment methods were applied to these solar ponds and experiments were conducted to study the turbidity reduction in the solar ponds. In the RMIT magnesium chloride solar pond, diluted hydrochloric acid was injected in the pond to reduce the pH and turbidity levels. Algal blooms were observed and found in the pond where the pH was between 5.5 and 8. It was observed from the experimental study that pH values should be kept below 4.5 to maintain low turbidity and prevent algae growth. The introduction of brine shrimps was also found to be very effective and economical to control algae, provided the oxygen has not depleted due to advanced heavy algal growth. The investigation concluded that hydrochloric acid could be used initially as a shock treatment to kill all the algae and then brine shrimps could be introduced to control the growth of algal and maintain transparency. This analysis showed that by using a combination of chemical and biological treatment methods, the pond clarity can be maintained and the thermal efficiency of the solar pond can be improved.

Research Spotlight: Assessing regional impacts of geoengineering

As the climate warms along with rising levels of atmospheric carbon dioxide (CO2), geoengineering has been suggested as an emergency option to cool the planet. One possibility is implementing a solar radiation management project, such as injecting sulfate aerosols into the stratosphere or deploying a solar “sunshade,” to counteract global warming by decreasing the amount of sunlight that reaches Earth's surface. However, a global intervention would have different regional impacts. For instance, geoengineering could result in decreased precipitation and increased droughts in some regions, with serious consequences for some human populations.

Research Spotlight: Satellites monitor air pollutant emissions in China

A new satellite study verifies that Chinese emission control efforts did reduce power plant emissions of sulfur dioxide (SO2), a harmful gas that causes acid rain and can form sulfate aerosols; these aerosols play an important role in the climate system by affecting clouds and precipitation patterns and altering the amount of sunlight that is reflected away from Earth.

Research Spotlight: Simple description of atmospheric organic aerosol

Atmospheric organic aerosols consist of a variety of organic molecules that are either directly emitted into the atmosphere or formed through chemical reactions in the atmosphere. Organic aerosols can affect climate by altering the amount of sunlight that is reflected away from Earth. Because the aerosol composition changes as chemical reactions take place in the atmosphere and air masses move and mix, it is difficult and time consuming for atmospheric chemistry models to include the details of the evolution of organic aerosol composition. A new study shows that it may not be necessary for models to include all the details.

Effect of Season of Inoculation on Immune Response to Rubella Vaccine in Children

The yearly seasons are marked by changes in the amount of sunlight. Ultraviolet radiation (UVR) is known to adversely affect the course of viral infections, immunologic memory and cellular and humoral immune responses. Our objectives were to investigate potential differences in the immune response of the rubella vaccine after 3-4 years by season of inoculation. Children aged 4-5 years attending four kindergartens in villages in northern Israel, all of whom had been vaccinated at 1 year of age, were enrolled in the study. Participants were divided into three groups by season of the year in which the inoculation was performed: summer (N = 63), winter (N = 36) and intermediate (N = 104). Main outcome measures were mean geometrical titer of rubella antibodies and complete, partial or no immunity to rubella by season of inoculation. Of the 203 children tested, 186 (91.6%) had adequate antibody levels, 7 (3.4%) had equivocal levels and 10 (4.9%) had inadequate levels. Significantly higher mean geometrical titers were found in the winter-inoculated compared with the summer-inoculated group (73.0 ± 2.6 vs 47.6 ± 2.8; p < 0.05). The same tendency was noted in the percent of infants properly immunized. This preliminary study shows a strong correlation between the immune response to rubella vaccine and the season of vaccination. Immunogenicity may be improved by inoculating children during seasons of less sunlight or by reducing the children's exposure to sunlight following inoculation. This practice is especially important in areas with extreme seasonal variability in solar radiation and tropical areas. Further studies are needed to corroborate and expand these findings.

Simulation of nanorod structures for an amorphous silicon-based solar cell

Through the use of three-dimensional (3D) technology computer aided design (TCAD) numerical simulations, the authors have designed a nanorod solar cell that can solve the conflict between high light absorption and efficient carrier transport in most amorphous silicon-based thin film solar cells. This novel structure involves the use of an n-type amorphous silicon (a-Si:H) nanorod on the substrate, an a-Si:H i-layer and an a-SiC:H p-layer which are sequentially grown along the surface of each n-type a-Si:H nanorod. Sunlight is absorbed along the axial direction of the nanorods, while carrier transport is along the radial direction. The nanorod used in this study was long and therefore it could absorb a high amount of sunlight, while the solar cell was still thin enough for effective transport of photo-generated carriers.

Effect of shade and shading history on species abundances and ecosystem processes in temporary ponds

Summary1. The amount of sunlight that an ecosystem receives is an important determinant of primary productivity, which in turn can influence species diversity and nutrient cycling. Here, we examine the effects of shading and shading history on ecosystem processes, macroinvertebrate diversity and development of dominant ecosystem states in field‐based aquatic mesocosms.2. We found that there were large effects of the level of shade, but few effects of shading history. Increasing light increased the biomass of filamentous algae (metaphyton) which increased the overall productivity of the ecosystem, and shifted the invertebrate community from one with more mosquitoes (filter feeders) to one with more anuran tadpoles (algal grazers).3. There was also an effect of shading history, where increased shade led to changes in the macroinvertebrate communities that were maintained after shade was reduced in the later part of the experiment.4. Finally, our results indicated that correlations between ecosystem processes, specific key macrofauna and the development of pond ecosystem states were greater than correlations of these factors to shading treatments. These results suggest that the history of community assembly can have a greater impact on the development of ecosystem processes than diminishing light by as much as 50%. However, light may have a potentially strong indirect effect and may impact the communities through altered bottom‐up structuring forces.

Occurrence, proportion, and vertical distribution of red heartwood in paper birch

Normal paper birch ( Betula papyrifera Marsh.) wood has a clear and uniform color. However, some paper birch trees contain reddish-brown-, discolored wood known as red heartwood. Its occurrence, proportion, and vertical distribution were investigated. One hundred and fifty trees were randomly sampled from three stands located at the Montmorency Forest, 75 km north of Quebec City, Quebec, Canada. A subsample of 18 trees showing occurrence of red heartwood at stump height were felled, and 5 cm thick disks were cut at every 0.5 m of height. Red heartwood volume, proportion, and vertical distribution were determined from the disks. Trees with larger diameter at breast height and lower tree height had a higher probability of red heartwood occurrence. Red heartwood starts occurring in 40-year-old trees on average in the stands studied. The volume of red heartwood was positively correlated with tree age, and the proportion of red heartwood was positively related to tree age, and negatively related to the amount of sunlight on the live crown. Red heartwood proportion was 13.3% of the tree merchantable volume, mostly located under the live crown.

Sources, nature and influence on climate of marine airborne particles

Environmental context. Climate models are of considerable interest to scientists and the general public given the increasing awareness of global climate change. A large uncertainty in climate models is the influence of airborne particles on the amount of sunlight that clouds reflect back to space. Since oceans comprise 70% of the Earth’s surface, it is important that we gain an understanding of the factors that control the sources and nature of marine airborne particles. This work describes previously unexplored features of the marine aerosol at a clean site exposed to the Southern Ocean and its environmental importance, which will be of benefit to future climate models. Abstract. Airborne particles (aerosol) collected at Cape Grim, Tasmania, in February 2006 in baseline conditions were examined by transmission electron microscopy. Particles recognised as marine exopolymer gels, and aggregates of insoluble organic particles that have diameters of ~40 nm, formed 9% of the particles larger than 200 nm. Once water-soluble compounds were removed by dialysis, the proportion rose to 30%. The gels and exopolymers were mainly of marine algal and bacterial origin. Their highly surface-active properties make them potentially environmentally important in the aerosol because of their ability to act as cloud condensation nuclei. The chemical constitution of particles in the 80–200-nm diameter size range is controversial, and widely varying estimates of the proportion of sea salt they contain have been published. Possible reasons for this are discussed. The present work supports the lowest estimate.

Risk Factors for Heatstroke among Japanese Forestry Workers

We examined the risk factors for heatstroke among forestry workers in Japan during the summer. We distributed a questionnaire to 124 forestry workers to determine heatstroke symptoms, degree of sweating and hydration, as well as perceived hotness and amount of sunlight at work sites. Forty of the workers (32.3%) reported experiencing heatstroke symptoms. Thirteen and 21 of them reported such symptoms during July and August, respectively. Eleven workers experienced heatstroke at around 14:00; 5 and 4 developed symptoms at around 11:00 and 10:00, respectively. Groups with and without heatstroke symptoms significantly differed in terms of perceived hotness (p<0.05), sunlight (p<0.05), degree of sweating (p<0.01) and frequency of hydration (p<0.05) while working. Heatstroke symptoms developed in 60.6% of workers aged up to 50 yr, but in only 22.0% of those over the age of 51 (p<0.01). Multiple regression analysis selected the following key variables associated with the development of heatstroke symptoms (R(2)=0.236 and p=0.006): frequency of urination, hotness, BMI and years of forestry work (standard coefficients: +0.229, +0.194, +0.280 and -0.162, respectively). The results of the present study showed that one third of forestry workers developed some symptoms of early heatstroke during summer forestry work. Furthermore, the results indicate that a short duration of forestry service was one of the risk factors contributing to the onset of heatstroke, in addition to heat stress, loss of body water and electrolytes, and obesity.

An analysis of factors that influence personal exposure to toluene and xylene in residents of Athens, Greece

BackgroundPersonal exposure to pollutants is influenced by various outdoor and indoor sources. The aim of this study was to evaluate the exposure of Athens citizens to toluene and xylene, excluding exposure from active smoking.MethodsPassive air samplers were used to monitor volunteers, their homes and various urban sites for one year, resulting in 2400 measurements of toluene and xylene levels. Since both indoor and outdoor pollution contribute significantly to human exposure, volunteers were chosen from occupational groups who spend a lot of time in the streets (traffic policemen, bus drivers and postmen), and from groups who spend more time indoors (teachers and students). Data on individual and house characteristics were obtained using a questionnaire completed at the beginning of the study; a time-location-activity diary was also completed daily by the volunteers in each of the six monitoring campaigns.ResultsAverage personal toluene exposure varied over the six monitoring campaigns from 53 to 80 μg/m3. Urban and indoor concentrations ranged from 47 – 84 μg/m3 and 30 – 51 μg/m3, respectively. Average personal xylene exposure varied between 56 and 85 μg/m3 while urban and indoor concentrations ranged from 53 – 88 μg/m3 and 27 – 48 μg/m3, respectively. Urban pollution, indoor residential concentrations and personal exposures exhibited the same pattern of variation during the measurement periods. This variation among monitoring campaigns might largely be explained by differences in climate parameters, namely wind speed, humidity and amount of sunlight.ConclusionIn Athens, Greece, the time spent outdoors in the city center during work or leisure makes a major contribution to exposure to toluene and xylene among non-smoking citizens. Indoor pollution and means of transportation contribute significantly to individual exposure levels. Other indoor residential characteristics such as recent painting and mode of heating used might also contribute significantly to individual levels. Groups who may be subject to higher exposures (e.g. those who spent more time outdoors because of occupational activities) need to be surveyed and protected against possible adverse health effects.

The Effect of Sunlight on Postoperative Analgesic Medication Use: A Prospective Study of Patients Undergoing Spinal Surgery

Exposure to natural sunlight has been associated with improvement in mood, reduced mortality among patients with cancer, and reduced length of hospitalization for patients who have experienced myocardial infarction. Our aim was to evaluate whether the amount of sunlight in a hospital room modifies a patient's psychosocial health, the quantity of analgesic medication used, and the pain medication cost. A prospective study of pain medication use was conducted in 89 patients undergoing elective cervical and lumbar spinal surgery where they were housed on either the "bright" or "dim" side of the same hospital unit. Analgesic medication was converted to standard morphine equivalents for interpatient comparison. The intensity of sunlight in each hospital room was measured daily and psychologic questionnaires were administered on the day after surgery and at discharge. Patients staying on the bright side of the hospital unit were exposed to 46% higher-intensity sunlight on average (p = .005). Patients exposed to an increased intensity of sunlight experienced less perceived stress (p = .035), marginally less pain (p = .058), took 22% less analgesic medication per hour (p = .047), and had 21% less pain medication costs (p = .047). Age quartile was the only other variable found to be a predictor of analgesic use, with a significant negative correlation (p <.001). However, patients housed on the bright side of the hospital consistently used less analgesic medications in all age quartiles. The exposure postoperatively of patients who have undergone spinal surgery to increased amounts of natural sunlight during their hospital recovery period may result in decreased stress, pain, analgesic medication use, and pain medication costs.

‘I Need Time to Grow’: The Transitional Year

Not every student is developmentally ready to move on to first grade after a year of kindergarten. The best gift we can give to those who aren't, Ms. Harris has found, is an extra year to mature -- mentally, socially, and emotionally -- in a nurturing environment. WHILE WATERING MY plants near the kitchen window one morning, noticed that one particular plant, though healthy in appearance, was not flourishing like the others had rooted at about the same time. All had received the same amount of sunlight, well-prepared soil, water, and pruning, and since had not moved them, the temperature was the same for all. Yet the green leaves of this plant had not matured as rapidly, the stems were not as strong, and the overall size of the plant was much smaller. As continued to ponder these differences, it occurred to me that perhaps this one plant just needed more time before its roots took hold in that growth spurt that leads to maturity. Isn't that just the way it is with children? When see the kindergartners spilling into our school each fall, I'm always struck that they are alike in so many ways, yet different in so many others. We provide all of them with a bounty of care, nurturing, and attention, and it seems that they should master the social skills, soak up everything teachers can pour out for them, and mature at an ever- quickening pace. Yet, as they near the end of that kindergarten year, many of the children do not seem to possess the maturity, both academic and social, that they will need for their replanting in first grade. At my school and others throughout the country, educators long ago saw the need for the transitional classroom, a place where normal children would be given the time they need to acquire maturity, to master work habits, to refine skills, and to develop the attention span that is so critical to success in the early grades. recently came upon an old cartoon that had been keeping. It showed two kindergarten boys coming out of their classroom. One was saying to the other, I plan to take a year off between kindergarten and first grade to myself. suspect that more than just a few kindergartners need to find themselves during an extra year's time between kindergarten and first grade -- a year that can stimulate them to further learning and support their development of positive self- esteem. When think back over the years about the students I've known who seemed to succeed with ease in the early years and compare them to those who struggled, the major difference that see has to do with readiness -- developmental readiness. All Grown Up and No Place to Go, David Elkind writes, In New Hampshire children are not hurried. It is one of the few states in the nation that provides 'readiness' classes for children who have completed kindergarten but who are not yet ready for first grade.1 Yes, we are a society that is in a hurry, but where are we going, and what will we get there with, if our young children are not fortified and nurtured in the early years of growth? As Nancy Bohl so clearly put it many years ago in her special message to parents, the step between kindergarten and first grade is a giant one, and for those who are not developmentally ready, it can lead to frustration and failure.2 recently participated in a panel discussion with several kindergarten teachers who bear the responsibility of recommending (or requiring) that students in their classes attend a transitional class for a year rather than passing directly into first grade. the case of recommending transition, parents have the option of choosing whether the student moves on to first grade or goes to the transitional year. If a student is required to attend the transitional class, there is no option, and the child must be enrolled in the transition program. These are not easy decisions that teachers make overnight. They think long and hard and observe the children in their kindergarten classes closely as they work throughout the entire year to evaluate each child's readiness for first grade. …

Seasonal variation in postnatal depression

Background: We evaluated the occurrence of postnatal depression in general and during different seasons as part of a larger longitudinal mother–child follow-up study. Method: One hundred and eighty-five mothers, from the maternity wards of University Hospital of Oulu, Finland, completed a self-rating depression scale, the Edinburgh Postnatal Depression Scale (EPDS) twice: first at hospital 2–7 days after delivery and the second time at home 4 months after the delivery. Different psychosocial variables were mapped out to avoid any confounding factors. The year was divided in two separate ways: first, three different time periods were selected by the amount of sunlight: dark (October–January), intermediate (February, March, August, September) and light (April–July), and second, the year was divided by seasons. The results were analysed by the χ 2-test for multinomials. Results: Sixteen percent (16.2) of mothers were scored as being depressed using 13 as a cut-off point immediately after the infant was born. Thirteen percent (13.0) were depressed measured 4 months postpartum. There was more mild depression in the autumn (ratio observed/expected 1,62; 95% confidence interval 1.05–2.19) immediately after delivery, using 10 as a cut-off, and less depression in the spring (0.27; 0.00–0.62) measured at home later, using 13 as a cut-off. When using classification by the amount of light there was more depression during the dark time (1.58; 1.05–2.11) immediately postpartum. Limitations: The group sizes and the amount of sample sizes collected within each month are quite small. Conclusions: It should be borne in mind that seasonal changes and alterations in the amount of light might influence the occurrence of postnatal depression.

レザーファーンのまだら黄化症発生に及ぼす遮光率と土壌水分の影響およびその防止指針

Leaves of leather fern are used as a foliage plant and Mottled Yellowing Syndrome (MYS) has been occurring on leaves cultivated in protected greenhouses at Hachijo Island since the 1990s. Experiments with different shading levels and soil moisture levels were carried out to develop cultivation methods that will prevent the occurrence of MYS. Relationships between the greenhouse environment and the occurrence of MYS were examined and the following results were obtained.The temperature of air, the canopy surface, and soil in the greenhouses were affected not only by shading levels but also by the color of the shading net. Air and canopy surface temperature decreased with an increase of shading rate with blue nets, however, temperatures under black nets were quite high due to the high surface temperature of the nets, which caused a high occurrence of MYS.Numbers of leaves decreased with an increase of shading level, but the leaf size increased. Chlorophyll content of the leaves increased with shading levels too.An optimum greenhouse environment to increase leaf size, leaf number, and chlorophyll content was obtained by a using a blue net with a 55% shading rate and the soil water potential controlled to less than 0.016MPa.MYS occurrence is increased by high temperature stress of the plant rather than high solar radiation in greenhouses. Also, MYS occurrence was decreased by frequent irrigation.MYS occurrence (%) can be estimated by degree days over 34°C of maximum air temperature for well-irrigated greenhouses, and by 1.5 times the degree days over 32°C for less-irrigated greenhouses. Farmers can manage the greenhouse environment to reduce MYS damage by applying these results.Greenhouses devoted to leather fern cultivation should be shaded (around half the amount of sunlight compared to outside) and should be controlled to keep good ventilation and soil moisture by frequent irrigation, which provides a desirable canopy surface-, air- and soil temperature, resulting in reduction of MYS damage and improvement in productivity and quality.

25-hydroxyvitamin D-1α-hydroxylase in normal and malignant colon tissue

Vitamin D affects calcium metabolism and prevents proliferation of colon cells in vitro. In human beings the main circulating form of vitamin D is 25-hydroxyvitamin D; to regulate calcium homoeostasis, this form must be converted to 1alpha, 25-dihydroxyvitamin D by 1alpha-hydroxylation in the kidney with 25-hydroxyvitamin D-1alpha-hydroxylase. Cultured transformed colon cancer cells can convert 25-hydroxyvitamin D(3) to 1alpha,25-dihydroxyvitamin D(3). We identified messenger RNA (mRNA) for 25-hydroxyvitamin D-1alpha-hydroxylase in normal colon tissue and in malignant and adjacent normal colon tissue. These findings support the notion that vitamin D might have a role in cell growth regulation and cancer protection, and might be the explanation for why the risk of dying from colorectal cancer is highest in areas with the least amount of sunlight.

高冷地一貫生産におけるシンビジウムの生育・開花に及ぼす開花リード発生時の低夜温管理の影響

The effects of low night temperature management in winter on growth and flowering of Cymbidium orchid were investigated in a greenhouse in a highland environment, using two varieties. The minimum night temperature was set at either 5°C or 15°C (control) from September 24, 1998 to May 31, 1999. In the other treatments, minimum night temperatures were set at 5°C then raised to 15°C on January 20, February 3, February 17, or March 3. The growth of lead bulbs was slightly poor in 5°C treatments in comparison with the control. However, the high-quality product ratio of 5°C treatments was equal or higher, and the flowering date was equal or earlier than the control. The treatment when the minimum night temperature was raised to 15°C, from 5°C on February 17 had the earliest flowering date, and fuel costs were about 60% less than the control. A low-cost way to manage the temperature for producing higher-quality Cymbidium plants is to set the minimum night temperature at 5°C from fall to spring, then raise it to 15°C after mid-February when the amount of sunlight has increased, promoting good flowering.

A Comparison of Diel Nest Temperature and Nest Site Selection for Two Sympatric Species of Freshwater Turtles

Diel nest temperature profiles were recorded form natural nests of eastern mud turtles (Kinosternon subrubrum) and Florida cooters (Pseudemys floridana) to determine whether nest microhabitat selection compensates for the effect of interspecific differences in nest depth on nest temperature. Kinosternon subrubrum nest depths were significantly shallower than those of P. floridana (t = 2.93, P < 0.01). We predicted that differences in nest depth would result in K. subrubrum nests being cooler at night and warmer during daylight than the deeper P. floridana nests. Diel temperature patterns agreed with out predictions at night, but P. floridana nest temperatures were not lower than K. subrubrum nest temperatures during the day. Soil composition, slope and soil moisture were similar for the nest of both species. However, the amount of sunlight reaching the soil above K. subrubrum nest sites was substantially less than the amount above P. floridana nest sites. We suggest that these species select habitats for oviposition that differ in the amount and types of vegetative cover, which in turn affect exposure to sunlight and ultimately nest temperature. 27 refs., 2 figs.

Visual Simulation of Leaf Arrangement and Autumn Colours

The representation methods of botanical trees have been presented so far by several researchers in recent years. A great deal of effort has been dedicated mainly to designing a procedural modelling method, especially a growth model of a tree/plant skeleton. However, few previous works have treated the problems of appropriate leaf arrangement and autumn colour evolution of a leaf which are essential to giving natural and seasonal impressions in a close-range view of a tree. In this paper, we will present the simulation methods for these attractive problems based mainly on the estimation of the amount of sunlight and the brightest direction of each part of every leaf.