Sunlight Environments Research Articles

Quality and growth of mangaba (Hancornia speciosa) seedlings according to the substrate and shading

The use of suitable substrates and growing environments are essential to produce high quality seedlings. This work evaluated shading levels and different substrates to produce mangaba seedlings. Growth environments with 0, 18, 35, and 50% shading were evaluated. In these environments, four substrates (S) were obtained from the combinations of soil (So), cattle manure (M), commercial substrate (CS), sand (Sa) and fine grain vermiculite (V), where: S1 = 0% So, 45% M, 20% CS, 20% Sa, 15% V, S2 = 15% So, 30% M, 20% CS, 20% Sa, 15% V, S3 = 30% So, 15% M, 20% CS, 20% Sa, 15% V, and S4 = 45% So, 0% M, 20% CS, 20% Sa, 15% V. For each growth environment, a completely randomized experimental design with five replications of five seedlings was adopted. The substrates S2 and S3 originated the best seedlings with the largest number of leaves, the largest dry mass of shoot, root, and total, and the highest Dickson quality index. The highest plants were obtained in the substrate S2. In the full sunlight environment, the conducted plants in S2 presented larger neck diameter. The environments with 0 and 18% of shading provided plants with larger leaves, larger aerial and total phytomass, and Dickson quality index. The environment in full sunlight promoted plants with a larger diameter. Therefore, it is recommended to produce seedlings on substrates S2 and S3 and in environments of 0 and 18% of shading.

Impacts of climate changes on pregnancy and birth outcomes: A review

This study aimed to review the impact of climate change around the world on the incidence of emerging and noncommunicable diseases in sensitive and vulnerable individuals, such as pregnant women and newborns. The combination of keywords such as climate change, ambient temperature, pregnancy outcomes, spontaneous abortion, preterm birth, stillbirth, autism, orofacial cleft, cleft palate, heart disorders, and diabetes was used for comprehensive search on reputable citation databases such as Scopus, PubMed, Web of Science, and Google Scholar, throughout research conducted previously with a focus on the years from 2018 to 2020. The results of the literature cited showed that long-term exposure to high temperatures reduced birth weight. Heat has been reported to have serious adverse effect than cool weather for preterm birth. A significant association has been reported between seasonal changes and diabetes and gestational hypertension. Climate changes, by increasing infant mortality and miscarriage, have made a difference in sex ratios. Further, the development of neonatal abnormalities such as hypospadias, autism, cleft palate, and heart disorders has been significantly associated with climate change. Seasonal changes, rising temperatures, sunlight, increased ultraviolet rays, and ozone concentration have been suggested to involve in the prevalence of cleft palate. Changes in relative humidity, temperature, sunlight, oxygen pressure, and elevated environments have also contributed to the development of heart disorders. This review showed that climate change has played an important role in the incidence and prevalence of emerging diseases. Hence, climate change has adverse effects on pregnant women and neonates. This study confirms critical importance of climate change and its negative effect on susceptible people and next generation.

Study on the influence of sunlight and ventilation on outdoor activity space of residential district

Outdoor activity space in residential districts is an important place for daily leisure activities of urban residents, whose comfortable level is directly affected by sunshine environment and ventilation environment. In this study, three residential areas represented in Hangzhou were selected. First, models were established to analyze the sunlight environment, and the suggestions were proposed to improve the sunshine conditions based on the research results. Secondly, the CFD wind environment simulation analysis method is adopted to analyze the ventilation environment of the three residential areas and discuss the solutions to the corresponding problems. The research conclusion can provide reference for the planning and design of outdoor activity space in urban residential districts.

Moderate shade environment facilitates establishment of desert phreatophytic species Alhagi sparsifolia seedlings by enlarge fine root biomass

Phreatophytic species (Alhagi sparsifolia Shap.) is commonly found to distribute in open area with full sun light environment without shading, and spontaneous occurrence of seedlings in mixed species communities is rare in arid and semi-arid regions. Seedlings and field-grown perennial plants at the southern rim of the Taklamakan Desert were grown under three light availability, i.e., full sun light, 80 and 20% of full sun light treated as high-light (HL), moderately high-light (MHL), and low-light (LL) groups. Plastic acclimation of leaf morphological and photosynthetic traits induced by low light was evident. Low-light-grown plants exhibited higher maximum photochemical efficiency (F v/F m) and relatively low assimilation rate (P n ), while difference in daily P n between the HL and MHL was not significant. Photosynthetic efficiency at the HL on summer midday was constrained partially due to lower quantum yield of electron transport at the primary quinone acceptors between photosystem II and I. Compared with the HL and LL, seedlings at the MHL group had larger relatively growth rate, net primary production per plant, and longer assimilative branch. Allocation proportions of biomass into root, assimilative branches, leaves, and stem, root/shoot ratio, and specific root length between the HL and MHL were, respectively, similar. However, very fine root biomass (<1 mm) was significantly enlarged by the MHL, which directly contributed to biomass production. Collectively, plant growth of A. sparsifolia favored by the MHL was mainly ascribed to rapid growth rate, photosynthetic efficiency without suffering midday stresses, and importantly to strong root system featured by enlarged fine root biomass.

Synthesis of Photocatalytic Nanocomposite Biomaterials for Enhanced Water Filtration Application

Clean and drinkable water is a critical necessity for all human and economic development; unfortunately, millions of people do not have access to potable water, resulting in the death of over 2 million children every year. Over the past decade, emphasis has been placed on the synthesis and design of photocatalytic nanocomposites to enhance the chemical degradation of organic pollutants as a cost effective vehicle for clean water production. Amongst the many semiconducting nanoparticles explored in literature, TiO2has stood out for its favorable physiochemical properties, low toxicity, easy availability, high stability, and low cost. When TiO2is irradiated by ultraviolet light, there is creation an electron-hole pair which provides sites for effective reduction or oxidization of the pollutant, converting the pollutant to carbon dioxide, water, and mineral acids. One major shortcoming of TiO2 is related to the efficiency of these systems to harness the entire solar spectrum; therefore, a main focus of this work is the modification of the TiO2 nanoparticles to increase the photon capture efficiency in the visible light region. Of the various possible functionalization pathways, this work focuses on dye sensitization, noble metal deposition, and silane functionalization as well as understanding the synergy between all three. When looking at the rate of remediation of a organic dye pollutant in a simulated sunlight environment, the functionalized particles completely remediated an organic dye pollutant. These functionalized nanoparticles were then deposited into a cellulose matrix of highly absorbent beads in order to prepare a nanocomposite. Results show there is a decrease in the chemical degradation of the pollutant when in the nanocomposite, but a significant increase in a physio-absorption capacity, thus maintaining the rate of total remediation. In addition, the binding interaction between the dye and the particle is a major component in chemical degradation; an aminosilane can be covalently added to the surface of the nanoparticle, and increase the ability of various dyes to adhere to the surface of the TiO2. The incorporation of Ag-functionalized nanocomposites resulted in a synergistic antimicrobial effect, which eliminated both E. coli and S. aureus from the water sample, in addition to increasing the photochemical degradation rate. The specific aim of this work was to create functionalized TiO2 particles with silane groups, organic dyes, and Ag, for the incorporation into a photocatalytic biomimetic nanocomposite membrane which utilizes sunlight to degrade pollutants and inhibit the growth of deadly bacteria.

A feasible scalable porphyrin dye for dye-sensitized solar cells under one sun and dim light environments

A new porphyrin dye Y1A1 has been devised for high performance dye-sensitized solar cells under the irradiance of either AM1.5G simulated sunlight or fluorescent/LED based dim light.

판상형 공동주택의 건폐율 및 용적률이 일조·옥외열환경에 미치는 영향 분석

As development density increases due to an increase in demand for apartment houses according to economic growth, a trend toward high density high rise apartment occurs. Accordingly, a bad influence is exerted on residential environment. Besides, the actual condition is that microclimate in urban space is getting worse due to an increase in artificial structure coverage ratio and imprudent apartment house block planning. For the improvement of urban microclimate and comfortable residential environment, a design that considers sunlight environment and outdoor thermal environment is needed in planning an apartment complex. And quantitative review and relevant baseline data accumulation is required. We quantitatively evaluated and analyzed an effect produced on the sunlight environment and outdoor thermal environment according to the change of floor area ratio and building coverage ratio, a main factor of building density in apartment houses. Sunlight environment is more sensitively affected by the change of building coverage ratio than that of floor area ratio under the same conditions of distance between buildings. The percentage of apartments having insufficient solar access decreased by an average of 2.1% according to the increase of floor area ratio. On the other hand, in case the building coverage ratio increased, it increased by an average of 25.2%. With regard to outdoor thermal environment, as floor area ratio increases, average building surface temperature decreases by 1.6~2.0% and average MRT decreases by 3.2~4.5%. Besides, it is possible to find that a daily variation in HIP becomes larger according to the increase of floor area ratio than according to the change of building coverage ratio. It is thought that the reason is that sunlight environment and outdoor thermal comfort in summer is largely affected by sun shade in comparison, and in case of HIP, the effect of artificial structure coverage ratio such as roof slab area is more dominant. It is believed that building density needs to be planned in consideration of comfortable residential environment in planning an apartment complex. And it is thought that a plan to which an environment-friendly technique is applied should be made according to whether floor area ratio and building coverage ratio is applied.

Evaluation Method for Energy Saving Effect of Reflective Thermal Insulation Coatings

According to the climate and energy saving characteristics in the hot summer and cold winter zone, especially in view of requirements for thermal insulation in summer, reflective thermal insulation coatings (RTIc) are gradually applied in building energy efficiency of exterior envelope. A feasible evaluation method for energy saving effect is very important for acceptance of energy efficient building construction. In this paper, thermal resistance has been used as the evaluation index. The energy efficiency of the reflective thermal insulation coatings was investigated. Four hot boxes were applied contrast test. Based on the qualitative and quantitative analysis of electricity consumption within 36 hours and comparative analysis of heating process simulating sunlight environment, thermal resistance of RTIc can be calculated on the basis of the correlation between power saving rate and thermal resistance so that energy saving effect of RTIc can be quantitatively characterized.

고령화에 따른 중소규모 노인요양원의 건축환경 분석에 관한 연구

Recently the concerns of aging & care according to the aged Society were on the increase about Home for the elderly facility. In order to moment, the purpose of this study is to analyze planning direction and Architectural Environments in medium and small scale Elderly Care Facilities. This survey are used to investigate with latest building data, which is Long-term Care Insurance Code for the Elderly was started on July 2008 in Korea. The results of this paper are as follows. First, various type of home for the elderly and the elderly group homes are spread out, attached to day care center type, nursing home type, city region type, countryside rural type, near the university and remodeling type. Secondly, per capita room area- are sufficient in regal comparison with . Thirdly, Sunlight environments is inappropriate condition as south direction proportion-41.95%. According to the present situation various facility type and model for our baby boomers generation should be more developed with preemptive systems of senior welfare concept.

Laser ranging at few-photon level by photon-number-resolving detection.

Sensitive laser ranging was demonstrated at few-photon level using photon-number-resolving (PNR) detectors. The reflected photon pulses from a non-cooperation remote target were distinguished in a sunlight environment of 2.5×103 lx by setting the discrimination threshold at 5-photon level. By comparing the detected photon numbers, two remote targets with different reflection coefficients were well recognized. PNR detection facilitated remote laser ranging of few-photon sensitivity with similar capabilities of linear optical detectors. This technique avoids photon-counting saturation and is important for ultra-long distance LIDAR and 3D imaging at a few photon level.

서울시 단독주택지의 독립형 저층공동주택 제안에 관한 연구 - 답십리 재건주택지를 중심으로 -

As a measures for improving a housing environment, this study suggests a planning of detached low-rise multi-plex houses, which are applicable to part of the reconstruction housing site in Dapsipri, one of the detached public housing sites constructed in 1956. The purpose of this study is to suggest an architectural alternative, which can improve the quality of dwelling while maintaining the residential environment of the detached housing site. The planning of detached low-rise multi-plex houses for the reconstruction housing site in Dapsipri has the following features: 1)This planning ensures the equal quality of sunlight environment by considering the current physical housing density and by arranging four types of unit housing modules which consider the width and direction of streets. 2) This planning uses a rehabilitation redevelopment method for each lot, which has dilapidated buildings. This approach will be able to maintain previous housing lots and road systems where various housing groups have been formed over the years in the reconstruction housing site. 3)This planning provides an easy access to roads by increasing the width of inner streets within unit housing and by considering the geographical condition of each lot. 4)This planning provides community space to ensure connectivity among residents and to revitalize communications among residents. It designs public streets as a community space through an inward common space, which directs toward housing blocks, in addition to the outward common space, which directs toward the roads. This study discovered that the current residential environment of the Dapsipri reconstruction housing site is poor. To improve such a poor living environment, this study suggests a detached low-rise apartment planning, which still maintains the existing housing density and the existing geographical context, by taking a rehabilitation redevelopment approach. The planning suggested in this study will be able to restore physical rationality. However, it will face limitations in improving residents' awareness about redevelopment and in leading to a flexible interpretation of the related laws.

Preferred solar access in high-density, sub-tropical housing

Appropriate solar access is considered to be important to residents’ health, comfort and daily living. In the past few decades, guidelines and standards have been formulated for the provision of sunlight in low-density housing. However, in sub-tropical, high-density housing like that found in Hong Kong, relevant guidelines and standards are generally lacking. At the same time, better provision of sunlight to such housing has become a matter of concern. Residents’ preference for solar access is very important to the formulation of standards for solar access and daylighting, as well as urban planning and building design. This paper presents the results of questionnaire surveys regarding residents’ preferences for solar access in terms of timing, duration and location. Computer simulation provides information on the actual sunlight environment of the visited households. Policy-makers, as well as planners and architects, should take the findings into account when establishing appropriate guidelines and standards for high-density tropical cities like Hong Kong.

장파장 근적외선 조명 및 밴드 패스 필터 기반 이동형 홍채 인식 시스템 및 성능 평가

Recently, there have been previous research about the iris recognition in mobile device to increase portability, whose accuracy is affected by the quality of iris image. Iris image is affected by illumination environment during the image acquisition. The existing system has high accuracy in indoor environment. However the accuracy is degraded in outdoor environment, because the gray levels of iris patterns in image are changed, and ghost and eyelash shading regions are produced by the sunlight of various wavelengths into iris region. To overcome these problems, we propose new mobile iris camera system which uses the near-infrared (NIR) light illuminator of 850 nm and band pass filter (BPF) of 850 nm. To measure the performance of the proposed system, we compared it to the existing one with the iris images captured in indoor and outdoor sunlight environments in terms of the equal error rates (EER) based on false acceptance rate (FAR) and false rejection rate (FRR). The experimental result showed that the proposed system had the lower EERs than those of previous system by 0.96% (with frontal light in indoors), 4.94% (with frontal light in outdoor), 9.24% (with side light in outdoor), and 7% (with back light in outdoor), respectively.

Residents’ preference of solar access in high-density sub-tropical cities

Solar access refers to the ability of a living unit to continue to receive sunlight without obstruction from any other properties or structures. The provision of appropriate solar access is considered to be important to residents’ health, comfort and daily living. Guidelines and standards for the provision of sunlight have been formulated in the past few decades in low-density living environment. In sub-tropical high-density living environment like Hong Kong, associated guidelines and standards are generally lacking and it has become a growing concern for better provision of sunlight to residential units. It is also important to consider residents’ preference of solar access in the formulation of standard for solar access and daylighting, as well as urban planning and building design. The present paper presents the results of a questionnaire survey regarding residents’ preference of solar access in terms of time, amount, place, and purpose of the exploitation of sunlight, as well as an exploratory factor analysis (EFA) which examines the influence of environmental parameters on residents’ preference. Results show that the majority of the respondents (72.0%) were satisfied with the current situation of solar access in their households. Only 12.4% of the respondents felt unsatisfactory about solar access of their flats. Over half of the respondents preferred to have sunlight penetration into their households in the morning. There is likely a need to improve the provision of solar access in terms of the time of sunlight received by residents since only about 40% of the respondents had the same time of sunlight entering their flats as they expected. There are not any particular preferences of the expected amount of solar access. Sufficient solar access was found to be more important than view outside respondents’ flats with an overwhelming 70.2% of the respondents in favor of sufficient solar access. The EFA results indicate that observed microclimatic parameters were the dominant influencing factors and closely followed by visual elements of residents’ subjective feelings about their flats. It implies that the incorporation of microclimatic environments into current design standard and guidelines should be considered. Further studies can also be conducted to examine the behavior of residents, i.e. activities occurred in the units, in more details. Current findings provide a basis of the preference of residents to solar access of residential flats in high-density tropical cities using Hong Kong as a case study. Policy-makers, as well as planners and architects, should therefore take the findings into account when establishing appropriate guidelines and standards, especially for high-density subtropical cities, in order to provide residential units with better sunlight environment.

Enhancing the Precision and Spatial Acuity of Point Quadrat Analyses via Calibrated Exposure Mapping

Modeling canopy sunlight environments requires precise measurements of biomass distribution and photon flux distribution (PFD). However, customary methods for obtaining these measurements are limited in their precision and practicality. Point quadrat analysis (PQA), the standard for canopy architecture, is limited in spatial precision and the lack of calibration; while measurement of PFD across an entire canopy typically requires rigorous sampling protocols. New methods are introduced that combine PQA and photon flux measurements into a calibrated biomass and PFD model. These techniques, applied to sample data from a shoot-thinning study, revealed quantitative descriptions of canopy biomass distribution, light environment, and treatment efficacy.

A double-digitising method for building 3D virtual trees with non-planar leaves: application to the morphology and light-capture properties of young beech trees (Fagus sylvatica).

We developed a double-digitising method combining a hand-held electromagnetic digitizer and a non-contact 3D laser scanner. The former was used to record the positions of all leaves in a tree and the orientation angles of their lamina. The latter served to obtain the morphology of the leaves sampled in the tree. As the scanner outputs a cloud of points, software was developed to reconstruct non-planar (NP) leaves composed of triangles, and to compute numerical shape parameters: midrib curvature, torsion and transversal curvature of the lamina. The combination of both methods allowed construction of 3D virtual trees with NP leaves. The method was applied to young beech trees (Fagus sylvatica L.) from different sunlight environments (from 1 to 100% incident light) in a forest in central France. Leaf morphology responded to light availability, with a more bent shape in well-lit leaves. Light interception at the leaf scale by NP leaves decreased from 4 to 10% for shaded and sunlit leaves compared with planar leaves. At the tree scale, light interception by trees made of NP leaves decreased by 1 to 3% for 100% to 1% light, respectively.

Low clouds and cloud immersion enhance photosynthesis in understory species of a southern Appalachian spruce–fir forest (USA)

High-altitude forests of the southern Appalachian Mountains (USA) are frequently immersed in clouds, as are many mountain forests. They may be particularly sensitive to predicted increases in cloud base altitude with global warming. However, few studies have addressed the impacts of immersion on incident sunlight and photosynthesis. Understory sunlight (photosynthetically active radiation, PAR) was measured during clear, low cloud, and cloud-immersed conditions at Mount Mitchell and Roan Mountain, NC (USA) along with accompanying photosynthesis in four representative understory species. Understory PAR was substantially less variable on immersed vs. clear days. Photosynthesis became light-saturated between ∼100 and 400 μmol · m(-2) · s(-1) PAR for all species measured, corresponding closely to the sunlight environment measured during immersion. Estimated daily carbon gain was 26% greater on clear days at a more open canopy site but was 22% greater on immersed/cloudy days at a more closed canopy site. F(v)/F(m) (maximum photosystem II efficiency) in Abies fraseri seedlings exposed to 2.5 min full sunlight was significantly reduced (10%), indicating potential reductions in photosynthesis on clear days. In addition, photosynthesis in microsites with canopy cover was nearly 3-fold greater under immersed (2.6 mmol · m(-2) · h(-1)) vs. clear conditions (0.9 mmol · m(-2) · h(-1)). Thus, cloud immersion provided more constant PAR regimes that enhanced photosynthesis, especially in shaded microsites. Future studies are needed to predict the survival of these refugial forests under potential changes in cloud regimes.

Role of Light and Phytochrome on Piper aduncum L. Germination: An Adaptive and Environmental Approach

ABSTRACT The influence of light on the germination process of two Piper aduncum ecotypes (SP and PR) were investigated and reported in this paper. This species has been getting special attention because the safrole content in their leaves. Seeds of both ecotypes were exposed to: daylight (DL), red (R), far-red (FR), blue (B), green (G), dark (DK) and reversible (RVB) to determine the light effects. Both ecotypes behaved similarly, except SP ecotype in the green light treatment, which reached an intermediary germination level. Seeds kept under far-red environment acquired light induced dormancy. This dormancy, however, was reversible and the most germination was observed by seeds first exposed to saturated levels of far-red and then exposed to red light (RVB treatment), a light regime consistent with transitional shading to direct sunlight environments (new deforested fields, gaps, and forest borders). Seeds also germinated under daylight and red light, but not far-red light, blue light, and dark treatments. Some seeds of the PR ecotype, but not the SP ecotype, germinated under green light treatment. The seeds do not germinate without light, classifying the plant as positively photoblastic. Daylight and red light treatments started germination on the 14th day for the SP ecotype and on the 14th and 15th day (for daylight and red light, respectively) for the PR ecotype. The fluency accumulated before the initiation of germination was higher than 1 × 103 μmol · m−2, evidence for the necessity of light for seed germination in this species. Apparently, seed germination in P. aduncum will be promoted by sowing under the shade of other commercial crops (15 to 20 days before harvesting).

Molar absorptivities of 2,4-D, cymoxanil, fenpropidin, isoproturon and pyrimethanil in aqueous solution in the near-UV

The absorption spectra of five pesticides, namely 2,4-dichloro-phenoxy acetic acid (2,4-D), cymoxanil, fenpropidin, isoproturon and pyrimethanil, have been measured in aqueous solution using a set-up consisting of two parallel absorption cells coupled to a CCD detector. The absolute values of their molar absorptivity coefficients ɛ were determined in the wavelength-range 240–344nm with a deuterium-lamp at room temperature (298±2K). Using the Beer–Lambert law, values of ɛ were also determined at 253.7nm with a Hg-Lamp: ɛ=145±14 for 2,4-D, ɛ=7940±920 for cymoxanil, ɛ=196±14 for fenpropidin, ɛ=7330±880 for isoproturon, ɛ=13200±1400 for pyrimethanil (in units of M−1cm−1). The quoted errors correspond to 2σ obtained from the least square fit analysis and the estimated systematic error of 5% due to the uncertainties in aqueous concentrations. For all the studied compounds, the absorbances measured were lower than 2.3 and did not exhibit any deviation from the Beer–Lambert's law.Our experimental data are discussed and compared to UV spectra of similar molecules when such data were available in the literature.Based on their UV spectra and the calculated fractions of these pesticides in the aqueous phase, their direct photolysis under sunlight environment could occur, except may be for fenpropidin, either in water surfaces or in aqueous droplets contained in the atmospheric clouds.

Environmental Effects on Cotton Fiber Carbohydrate Concentration and Quality

Cotton (Gossypium hirsutum L.) grown in reduced light environments produces inferior fiber compared with that produced in abundant sunlight environments. This response to low light suggests that insufficient photosynthetic assimilates are the cause of the fiber quality reductions. The primary objective of this research was to determine how fiber carbohydrates respond to varying levels of sunlight during development. A field study was conducted from 1995 to 1997 in which cotton was exposed to two light regimes during reproductive growth: (i) incident sunlight and (ii) 70% of incident sunlight achieved with shade cloth. Samples of fiber, ovules, and leaves subtending the boll were collected at 0, 14, 21, and 35 d post anthesis (DPA) and analyzed for starch, glucose, fructose, and sucrose. Fiber quality was determined at the end of the season. With some exceptions, the shade treatment reduced carbohydrates levels in the leaf and ovule tissue. At 14 DPA, starch was reduced 29% in fiber grown under shade. Sucrose levels in shade fiber was reduced 31% at 21 DPA. The carbohydrate reductions at 14 and 21 DPA occurred during a period of fiber development when strength is determined. These carbohydrate reductions parallel the 3% fiber strength reductions seen with low light. The reduced sucrose levels at 21 DPA induced by the shade also occur during fiber secondary cell wall deposition and match the lower fiber micronaire produced under shade. These data present compelling evidence that adequate carbon assimilates are required to produce fiber quality approaching genetic maximums.