Average Sun Research Articles

Chemical composition and potential pharmacological applications of Centaurea acaulis L.

Our study aimed to characterize the composition of the ethyl acetate extract obtained from Centaurea acaulis L. and assess its dermatoprotective and antioxidant properties. The secondary metabolite composition was established by high-performance liquid chromatography combined with mass spectrometry. The antioxidant activity was assessed using four different assays, including DPPH, β-carotene, CUPRAC, and reducing power assays. Furthermore, the in vitro photoprotective effect was evaluated by measuring sun protection. The HPLC-TOF/MS analysis identified the presence of 19 bioactive compounds in the ethyl acetate extract. Major components such as rosmarinic acid and 4-hydroxy benzoic acid were detected, along with other compounds including caffeic acid, cichoric acid, gentisic acid, p-coumaric acid, protocatechuic acid, ferulic acid, vanilic acid, gallic acid, apigenin-7-glucoside, catechin, kaempferol, and quercetin. The ethyl acetate extract of Centaurea acaulis L. exhibited strong antioxidant activity in DPPH, β-carotene, CUPRAC, and reducing power assays, outperforming standard antioxidants such as butylated hydroxytoluene (BHT) and butylated hydroxyanisole (BHA), tannic acid, and ascorbic acid. Additionally, the extract demonstrated a high ability to absorb UV radiation, with an average sun protection factor of 40.20 ± 0.11. These findings highlight the significant antioxidant and dermatoprotective potential of the ethyl acetate extract from Centaurea acaulis L., suggesting its potential use in cosmetic and dietary additive formulations.

Phase “Rise” of The 11-Year Solar Cycle with Contribution to Global Warming – Examples from The Bulgarian Meteo Stations’ Temperature Data

A high negative correlation between the average Sun Spot Number in phase “rise” in the 11-year cycle of solar activity and the annual average Earth’s surface temperature was observed in the data from several meteorological stations – first in the temperature data from meteorological stations in Bulgaria, and then from many stations from Europe and the world. As solar activity has decreased over the last 70 years – the last few solar cycles up to the 24th number have had a monotonically decreasing number of sunspots – their negative correlation with temperature results in a rising surface air temperature. This increase is related to processes in the Sun’s magnetosphere and has nothing to do with the increasing concentration of greenhouse gases in the surface atmosphere. The increasing concentration of greenhouse gases may be also a consequence of the processes taking place on the earth’s surface as a result of solar activity and is not a cause of the increasing temperature of the earth’s surface.

Association between sun exposure habits and disease progression in multiple sclerosis.

Higher latitude has been associated with increased occurrence of multiple sclerosis (MS) and with more severe disease. The aim was to study the impact of sun exposure habits on MS disease progression and health-related quality of life. Patients from a population-based case-control study were categorized based on sun exposure habits at diagnosis and were followed up to 15 years post-diagnosis through the Swedish MS registry (n = 3314) with regard to changes in Expanded Disability Status Scale (EDSS). Linear mixed models were used to analyse long-term changes, while Cox regression models, with 95% confidence intervals, were used to investigate outcomes, including 24-week confirmed diasability worsening, EDSS3, EDSS4, and physical worsening as measured by the physical component of the Multiple Sclerosis Impact Scale 29. Compared to average sun exposure (median value), low exposure to sunlight was associated with faster EDSS progression, increased risk of confirmed disability worsening (hazard ratio [HR] 1.48, 95% CI 1.21-1.81), increased risk of reaching EDSS 3 (HR 1.35, 95% CI 1.02-1.79), EDSS 4 (HR 1.47, 95% CI 1.01-2.20) and self-reported physical worsening (HR 1.27, 95% CI 1.00-1.62). Significant trends revealed a lower risk of unfavourable outcomes with increasing sun exposure. Very low levels of sun exposure are associated with worse disease progression and health-related quality of life in patients with MS.

Assessing the safety and efficacy of DIY-homemade sunscreens with natural, aromatic and herbal ingredients

Sunscreen products are widely used during the summer months to protect against increased sunlight exposure. While there have been advancements in the effectiveness and safety of commercial sunscreens, there is a growing interest in "completely natural" and homemade skincare products, including sunscreens. These homemade alternatives often incorporating aromatic and medicinal herbal preparations, are being touted as safe alternatives on online social media platforms and alternative health websites. It is essential to recognize that scientific research has primarily focused on evaluating the effectiveness and safety of commercially available sunscreen products. Concerns have arisen regarding the potential risks associated with non-commercial sunscreens, particularly those labeled as "homemade" or "completely natural." Therefore, it is crucial to investigate whether these DIY sunscreen products, advertised as natural and additive-free, pose any health threats due to their inadequate sun protection properties. This study aims to examine the formulations of these proposed homemade sunscreen products, specifically evaluating their durability, protection against ultraviolet A and B (UVA and UVB) radiation, and average sun protection factor (SPF) values from a toxicological perspective. Emphasizing the importance of safety in sunscreen products is paramount, as the use of unsafe sunscreens can lead to serious health risks, including skin cancer, premature aging, and other skin disorders.

Effect of Roof Inclination on Solar Panel’s Energy Output in a South-Western Nigerian City

This work sets up four photovoltaic (PV)-based solar power systems with adjustable solar panel inclination angle stands. It also varies the inclination angle of the solar panel every five days while recording daily energy delivered by the panels. The study finally compares the output energy recorded for different angles. This was done with a view to studying the effect of building roof inclination on the energy deliverable by solar panel installed on it. The set up consists of PV-based solar power systems with adjustable inclination angle stands for four 10 W solar panels which are on the same axis. Each solar panel was connected to a 42 Ah battery through multimeter and charge controller. A 25 W load was used to discharge the battery at night to allow fresh charge from the panels during the day. The multimeter was used to monitor the daily energy delivered. The solar panels were subjected to 0°, 25°, 50° and 75° inclination angles and faced to South direction at the Renewable Energy Laboratory, Osun State University, Osogbo, Nigeria. Data were recorded daily for 20 days by subjecting all panels to the considered angles for five days. The results obtained showed that the average energy delivered by panels installed at the stated inclination angles are 35.35 Wh, 32.25 Wh, 24.1 Wh and 13.95 Wh, respectively. This means that, for a specific building energy need, the steeper the roof (intended for panel installation), the more the amount of solar panel required to meet such energy. The results also showed various expressions that can be used to estimate daily average sun hour (ASH) based on roof inclination. For example, the estimated daily (ASH) for Osogbo and environs can be taken to be 4.22 hour, 3.15 hour and 1.82 hour for 25°, 50° and 75° roof inclinations, respectively.

Clinical and Dermoscopic Evaluation of Melasma in Men- An Observational Study at a Tertiary Health Care Centre in Western Odisha, India

Introduction: Melasma is one of the most common cause of facial hypermelanosis presenting as symmetrical hyperpigmented macules over sun exposed areas especially in women and sizeable proportion in men causing a detrimental effect on the quality of life. Aim: To evaluate the clinical profile and dermoscopic features of melasma in men. Materials and Methods: A cross-sectional, observational study was conducted at Veer Surendra Sai Institute of Medical Sciences and Research (VIMSAR), Burla, Odisha, India, from November 2018 to October 2020. 245 men, clinically diagnosed with melasma were included in the study with due consent and evaluated for age, family history, skin type, drug intake history, duration, duration of sun exposure, disease pattern, Melasma Area Severity Index (MASI) Score and dermoscopic feature. Data was collected using questionnaire, managed by Microsoft excel 2016 and analysed using Statistical Package for Social Sciences (SPSS) 20.0. Results: Melasma occurred most commonly in the age group of 31-35 years (37.9%) with mean age of occurrence being 34.5±7.9 years affecting most commonly Fitzpatrick skin type IV (47.3%). There was positive family history in 63 patients (29.7%) and history of Diabetes Mellitus (DM) type 2 in 24 cases (9.7%). There was increased occupational sun exposure in 93% of cases with average duration of exposure being 7-8 hours/day in 98 cases (42.9%). The most common clinical pattern observed was malar pattern in 156 cases (63.6%) and epidermal dermoscopic pattern in 128 cases (52.2%). Majority of cases had a MASI Score between 5-10 with mean being 8.7±7.7. On comparing MASI Score and sun exposure, the average sun exposure was highest for a MASI Score 20-25 i.e., 7.4 hours/day. Conclusion: The most common age group affected by melasma in males is 20-40 years, with prevalence being greater in higher Fitzpatrick skin type (III, IV), with positive history of occupational sun exposure and positive family history. The severity of melasma in form of MASI score was formulated. The knowledge acquired through the study can help bridge the knowledge gap to improve its management and quality of life.

Utilization of Solar Energy for Water Heating Application to Improve Building Energy Efficiency: An Experimental Study

The manuscript is written for flow escalation based on an experimental data for a Solar Assisted Heat Pump Water Heater (SAHPWH) increasing building energy efficiency. For the investigation, a Solar Assisted Heat Pump (SAHP) was conceived, manufactured, and tested in real time. The findings of the experiments shows that single glazing with average sun radiation of 600–750 W/m2, COP of approx. 6 can be obtained with identical heat gains. This study shows that when a flat plate collector of area 1.83 m (L) × 1.22 m (W) × 0.1 m (T) with a 0.5-mm-thick black copper plate absorber with clear glazing as a cover receives average radiation of 700 W/m2, then setup can supply 60 litres of water for residential use from 15 °C to 45 °C in approx. 70 min. In addition, the study finds that the collector efficiency factor F’ is likewise shown to have a direct connection with the absorber and an inverse relationship of tube spacing. The findings indicated that the technology has significant commercial potential, particularly in sectors such as with solar resources for improving building energy efficiency.

An Experimental Approach towards PV-Based Solar System Sizing for an Engineering Laboratory

This study aims at providing an experimental sizing procedure for a rooftop PV-based solar power system for an engineering laboratory. This was achieved by monitoring the peak power and energy delivered by an installed 20W solar panel into an 18 Ah battery. Knowledge of the average daily peak power and energy was used to determine the percentage rated capacity available for use and the sun hour. A load consumption comparison was also carried out with and without the connection of a load to inverter. In addition to this, the monitoring of the no-load consumption of the inverter was carried out. This was carried-out to ascertain the contribution of the inverter to the system. With the knowledge of the average daily energy deliverable, sun hour and the no-load power of the inverter, a sample sizing for basic electronic laboratory loads was done. The findings of the study reveals that the average available power is 89.35% of the solar panel rated capacity while the average sun hour is 4.38 h. It has also been shown that an approximate difference of 20 W exists between the power consumption of the load with and without its connection to the inverter. This value (i.e., 20W) has been recorded as the approximate no-load power for the inverter. The sample sizing done has shown that, the solar panel energy requirement of the system with inverter may be considerably higher than that without inverter.

Integrating Neural Network for Pest Detection in Controlled Environment Vertical Farm

Background: An integrated system for creating and maintaining controlled environment ideal for vertical farming prototype is demonstrated. The requirement of optimal artificial light for different growth stages of tomato and chilli plants is studied in detail and CNN model-based method for detection and classification of Leaf disease is also developed. Methods: The artificial environment ensuring adequate artificial lighting, moisture, and minerals was create by implanting various sensors and actuators to the plant beds and connected in network through a cloud based remote server. A CMOS image sensor module was used to monitor the various stages of plant growth. Findings: The duration and intensity requirement for germination, vegetation and flowering of both tomato and chilli plants are relatively lesser with artificial light condition than with sunlight. At the end of fifth epoch the developed convolution neural network model for detection and classification of leaf disease produced training and validation accuracies of 84.8% and 67.2%, respectively. Novelty: For different growth stages of tomato and chilli plants in north eastern India, the requirement of optimal artificial light is studied by exposing them to different light intensities. The study was conducted during summer (May-June) when the average sun exposure in eastern India was ~130- 190 hours. The captured images and data generated were used to monitor the status of the crops and identifying diseases with the application of Deep Learning models. Convolutional Neural Network (CNN) model-based method for detection and classification of leaf disease is presented. Keywords: Convolution Neural Network; Vertical Farming; Artificial Light; Pest Detection; Light Emitting Diode

Integrated water vapor over the Arctic: Comparison between radiosondes and sun photometer observations

The amplification of global warming because of the feedbacks associated with the increase in atmospheric moisture and the decrease in sea ice and snow cover in the Arctic is currently the focus of scientists, policy makers and society. The amplification of global warming is the response to increases in precipitation originally caused by climate change. Arctic predominant increases in specific humidity and precipitation have been documented by observations. In comparison, evapotranspiration in the Arctic is poorly known, in part, because the spatial and temporal sparsity of accurate in situ and remote sensing observations. Although more than 20 observations sites in the Arctic are available, where AERONET sun photometer integrated water vapor (IWV) measurements have been conducted, that information have been barely used. Here, we present a comparison of IWV observations from radiosondes and AERONET sun photometers at ten sites located across the Arctic with the goal to document the feasibility of that set of observations to contribute to the ongoing and future research on polar regions. Sun photometer IWV observations are averaged for three-time windows; 30 min, 6 and 24 h. The predominant dry bias of AERONET IWV observations with respect to radiosondes, identified at tropical and midlatitudes, is also present in the Arctic. The statistics of the comparison show robust results at eight of the ten sites, with precision and accuracy magnitudes below 8 and 2% respectively. The possible causes of the less robust results at the other two sites are discussed. In addition, the impact of selecting other temporal coincidence windows in the average sun photometer IWV used in the comparison were tested. Auto-correlation in diurnal sun photometer IWV could produce appreciable bias in the statistics used for the comparison. We suggest using only one pair of values per day, consisting in the daily mean IWV sun photometer and the IWV radiosonde observation value. This feature should be valid also for comparison of IWV from sun photometer and other instruments. Maximum 10% error level of IWV from sun photometer observations, when compared with radiosondes, have been found for the Arctic. It is in the same order of magnitude than at tropical and middle latitudes locations. It has been demonstrated the feasibility of AERONET IWV observations in the Arctic for research on this variable. AERONET standard instruments and its centralized-standard processing algorithm allow its IWV observations to be considered a relative standard dataset for the re-calibration of other instrumental IWV observations assuming radiosondes as the absolute standard dataset.

Facial Basal Cell Carcinoma: A Study of Causative Factors and Site-based Algorithm for Surgical Reconstruction.

Basal cell carcinoma (BCC) can be categorized as one of the commonly occurring skin malignancies in the world, with several variations in treatment protocols. Sun exposure has been attributed to its causality; however, other factors such as gender, age, and occupation also affect its incidence. We aimed to characterize the patient population who underwent surgical management for facial BCC at a tertiary referral hospital. Further, we have described an algorithm that may aid in surgical decision-making based on the location of the lesions on the face. We performed a retrospective chart review of all patients who presented with a facial BCC to our institution between 2018 and 2019. Data regarding patients' demographic characteristics, skin phototype, average sun exposure, occupation, residence place (rural or urban), and surgical outcomes were recorded. Sixty-eight patients underwent reconstructive procedures after oncologic resection of facial BCC: 41.2% were males and 58.8% were females. Forty-eight (70.6%) patients were from rural areas, and 20 patients (29.4%) from urban areas (P < 0.001). Twenty-six patients reported >2 h of sunlight exposure, 16 reported <2 h of continuous sun exposure, and 26 reported intermittent sun exposure. A significantly higher proportion of patients with facial BCC presented with a Fitzpatrick skin type 4 in comparison to types 3 and 5 (P < 0.001). The most common reconstructive technique was the V-Y advancement flap (n=22, 32.4%), followed by the forehead flap (n=12, 17.6%) and the Limberg flap (n=12, 17.6%). All the flaps were healthy post-operatively and none of them suffered from flap failure, infection, or suture line dehiscence. There was no recurrence at 1-year follow-up. This study gives a correlation between incidence of BCC and age, gender, and sun exposure in Indian population. In our experience, local flaps yield outstanding results and are the first choice for reconstruction of the face when composite defects are not present. Our algorithm aids in surgical decision-making.

An Analysis of Hybrid Energy Design for Yogyakarta International Airport (YIA)

The potential for solar and wind energy at YIA Airport is quite large so that it can be used as a renewable alternative energy source. Based on data obtained from BMKG of YIA, the average sun intensity at YIA Airport is 6.21 kWh/m2 while the average wind speed is 3.07 m/s. This potential can be used as solar and wind hybrid energy to meet some of the electricity demand at YIA Airport using photovoltaic modules and wind turbines. Design of the wind turbine refers to research conducted by Mihai Lates and Radu Velicu (2014), which implements a basic savonius type wind turbine with an aspect ratio (α) 2, diameter (D) 3.50 m, number of blades (n) 2. Solar array design uses an off-grid system, then will be hybridized with the wind turbine. Based on the calculation result shows that the required area of the solar array is 2282.87 m2 to produce 2574 kWh/day, while the number of turbines proposed is 143 units to produce 136.90 kWh/day. With this design and based on the calculation, electrical energy will be generated for 13.55% (2710.90 kWh/day) of the total electricity demand at YIA Airport.

Birth cohort-specific trends of sun-related behaviors among individuals from an international consortium of melanoma-prone families

BackgroundIndividuals from melanoma-prone families have similar or reduced sun-protective behaviors compared to the general population. Studies on trends in sun-related behaviors have been temporally and geographically limited.MethodsIndividuals from an international consortium of melanoma-prone families (GenoMEL) were retrospectively asked about sunscreen use, sun exposure (time spent outside), sunburns, and sunbed use at several timepoints over their lifetime. Generalized linear mixed models were used to examine the association between these outcomes and birth cohort defined by decade spans, after adjusting for covariates.ResultsA total of 2407 participants from 547 families across 17 centers were analyzed. Sunscreen use increased across subsequent birth cohorts, and although the likelihood of sunburns increased until the 1950s birth cohort, it decreased thereafter. Average sun exposure did not change across the birth cohorts, and the likelihood of sunbed use increased in more recent birth cohorts. We generally did not find any differences in sun-related behavior when comparing melanoma cases to non-cases. Melanoma cases had increased sunscreen use, decreased sun exposure, and decreased odds of sunburn and sunbed use after melanoma diagnosis compared to before diagnosis.ConclusionsAlthough sunscreen use has increased and the likelihood of sunburns has decreased in more recent birth cohorts, individuals in melanoma-prone families have not reduced their overall sun exposure and had an increased likelihood of sunbed use in more recent birth cohorts. These observations demonstrate partial improvements in melanoma prevention and suggest that additional intervention strategies may be needed to achieve optimal sun-protective behavior in melanoma-prone families.

Thin-layer mathematical modeling of apple slices drying, using open sun and cabinet solar drying methods

This paper aims to investigate the effect of climate conditions such as ambient temperature, humidity, pressure, sun radiation and pollution on sliced apples quality and drying time which are dried in an indirect forced cabinet solar drying (IFCSD) and open sun drying (OSD) systems. Both experiments were implemented at same place (Kabul, Afghanistan) and time. The IFCSD yield for saving time is 42.8 % which is more effective than drying in the OSD system. Simultaneously with the decreasing of sliced apple weight from 512.9 g down to 73.9 g, the water activity decreased from 0.955 down to 0.355 in the IFCSD system. For OSD system, the sample weight decreased from 512.6 g down to 78.4 g and its water activity from 0.955 down to 0.411. On the experiment day the average sun radiation was 571 w/m2 . The pressure drop between inlet and outlet of the dryer was 0.1 kPa. Different thin-layer mathematical models were investigated to identify the best model fitting the experimental data. The mathematical models’ performances were investigated by comparing the coefficient of determination (R 2 ), reduced chi-square (X2 ) and root mean square error (RMSE) coefficients. From all 11 applied thin-layer drying models the Page, Approximation diffusion, Verma et al and Midilli and Kacuk models are more fitted to our data.

Modeling of the Solar Thermal Energy Use in Urban Areas

Most of the generated electricity in Kosovo is produced from fossil fuel, a part of the energy comes from the import, while participation of renewable resources is symbolic, and a bias between the grid extension and the load of power generated sometimes results in shortage of electricity and thus frequent power cuts. The use of renewable energy and particularly the solar thermal energy represents one of the most promising alternative strategies. In Kosovo, the global horizontal radiation ranges from 1241 kWh/m2 per year in Shterpce to 1461 kWh/m2 per year in Gjakova, while the average for Kosovo can be estimated at 1351 kWh/m2 per year. The average sun duration for the city of Pristine is 5.44 h, while the average horizontal irradiation is 3.79 kWh/m² per day. Participation of energy consumption in household is still dominant - about 41.4% of the total consumption in Kosovo, 15% of this energy is used for domestic hot water. This energy demand can be lowered significantly by using improved building construction techniques and utilization of RES-s, especially solar thermal. The first step is to map the city in different areas to locate suitable locations for the installation of solar collectors serving sanitary hot water. The demand for sanitary hot water varies from object to object, this variation depends on whether the building is individual or collective, school institutions or religious buildings, for this reason the classification of buildings was done according to the request for sanitary hot water. After that the demand for sanitary hot water is calculated for several different institutions: Residential houses, Dormitories and Hospitals. For all of the above-mentioned cases the data for: solar fraction, solar contribution, CO2 avoided, collector temperature, financial analysis etc. are gained using the TSOL 2018 software. To evaluate the active energy for a time period, the daily, monthly and annual performance for three systems which are located in University Clinical Center of Pristine, Kosovo have been analyzed. In addition the results of the mathematical model, simulation and measured solar energy contribution for solar station in Infective disease clinic have been compared. In this paper, a proposal for replacing the conventional water heaters with the domestic solar water heaters (DSWH) is made. A case study for 38289 Residential households in Pristine has been selected. The initial cost of the solar water heater for the city is 60113730 €. The system saves 7274910 € annually and reduced C𝑂2 emission by 22973400 kg. The results from the paper show that the DSWH is economically feasible in Pristine and can result in fuel saving and CO2 emission reduction.

Serum Vitamin D Level in Patients with Coronary Artery Disease and Association with Sun Exposure: Experience from a Tertiary Care, Teaching Hospital in India

Background Vitamin D, a fat-soluble vitamin, has various extraskeletal effects, and several human and animal studies have suggested that vitamin D deficiency may be a contributory factor in the pathogenesis of coronary artery disease (CAD). However, such studies in the Indian subcontinent are either lacking or have shown conflicting results. Methods This was a descriptive cross-sectional study involving 121 patients with CAD from a tertiary care center and their 80 age-matched healthy controls. Serum vitamin D levels along with serum and urine chemistries were measured in both the groups. The average duration of sun exposure/day and use of sunscreen were also considered in the study cohort using a questionnaire. Serum vitamin D levels were categorized into deficient (<30 nmol/lit), insufficient (30–75 nmol/lit), and sufficient (>75 nmol/lit) groups. Results Among the cases, 51.2% of the patients were vitamin D deficient and 44.6% patients had insufficient vitamin D levels, whereas among controls, 40% and 31% of the population had deficient and insufficient levels of vitamin D, respectively. However, the mean value of the serum vitamin D level was not statistically different in the cases as compared to that of the controls (34.06 vs 40.19 nmol/lit) (P=0.08). Corrected serum calcium (9.26 vs 9.59 mg%) (P ≤ 0.0001) and serum albumin levels (4.21 vs 4.75 gm%) (P ≤ 0.0001) were lower in the cases than those of the controls. The average sun exposure/day was higher among the cases than that among the controls (2.93 vs 1.85 hours) (P=0.001). Conclusion Vitamin D deficiency is widely prevalent in Indian population despite abundant sunshine, and the duration of sun exposure is not correlated with serum vitamin D levels. Vitamin D deficiency is not associated with CAD. However, serum calcium is deficient in CAD patients as compared to the controls. Large-scale studies are required to explore the association further to evaluate the benefits of screening and correction of vitamin D deficiency in patients with CAD.

Prediction and Appraisal of Solar Radiations and Its Intensity in South East Geopolitical Region, Nigeria

This research work shows the variability of solar parameters. The parameters that are solar radiation, sun intensity and temperature were optimized and predicted in other to investigate its influence in Permanent site of Federal Polytechnic, Oko, Anambra State, South Eastern part of Nigeria. The research was conducted for the period of five days, 6:00am to 6:00pm daily on 6th to 10th December, 2017. Measuring the intensity of solar radiation is one of the directions used at an investigation of solar power and necessary for the implementation of photovoltaic systems in a particular geographical 'area. Instrument used for measuring the solar radiation is solarimeter which is based on the thermal or photovoltaic principles. The device harness two main components for measuring solar radiation, namely- direct radiation and diffuse radiation, with sensors based on the photovoltaic principles. The research tends to optimize and to develop the intended sun intensity and solar radiation principles and properties of the environs. From the optimization results, the maximum sun intensity of the geographical area is 957.620 w/m2 while the minimum sun intensity of the area is 2 w/m2. However, the maximum temperature of the geographical area is 39.4˚С while the minimum temperature of the geographical area is 18.8˚С. The average sun intensity of the case study is 356.644 w/m2. The optimization technic employed will ensure the efficiency of solar radiation, sun intensity and temperature variability of the geographical area in the study as a key to climatic issues and solar systems manufacturing.

Feasibility study of photovoltaic water pump for rice paddy irrigation

Diesel pumps are commonly used for irrigation purposes of paddy fields at locations far from the grid. Diesel pumps have low reliability because they require high maintenance costs. The use of photovoltaic is a valuable option because the selection decision is not only based on direct biya modal but also includes environmental costs. These solutions reduce the impact of global warming, mitigate negative effects on air quality and contribute to sustainable economic development. Daily sun conditions in Indonesia are average in the horizontal plane within the range of 5-7 kWh/m2/day and the average daily sun shines within the 7-9 hour. The availability of solar radiation is quite abundant and due to the high cost of grid connections, the pumping of irrigated rice paddy water is beneficial to the water needs for remote communities in Indonesia. It is known from some literature that the photovoltaic irrigation pump system is technically and economically feasible for very small systems in hectares orders. Technical and economic feasibility is determined as a function of the plant and geographical location, including climatic factors, soil quality, ground water depth and recharge rate. The objective of the research is to design a system of pumping irrigation of paddy field of photovolatics to replace previous diesel pumps that meet the criteria of feasibility standard. From simulation using PVSYST 5.0 software, it is known need of solar panel as many as 5 series module and 2 parallel module which fulfill the required eligibility criteria.

Designing and modelling of grid connected photovoltaic system (case study: EEU Building at Hawassa City)

Renewable energy sources are integral part of the present energy system because of the various problems, associated with conventional energy sources. Solar and wind are the major renewable energy sources. The renewable energy sources are sufficient enough to meet the world energy requirement. In this paper, a comprehensive analysis on energy output calculation of the photo-voltaic (PV) system is presented. The solar radiation effect is articulated based on monthly average sun shine hours. After local area solar potential is assessed, small plant is developed and designed for EEU building electric power supply, which is connected to the grid. Therefore, there is huge reduction in grid supply demand. The study uses different metrological data and simulates the grid connected PV technologies to end users, for decision making in PV energy investment. Performance ratio and specific energy is calculated as indicator for the plant feasibility in the area.

The association between Solar Lentigines and Type-2 Diabetes.

Background:Limited information exists between the associations of diabetes mellitus (DM) and solar lentigo (SL); a benign, common skin lesion characterized by hyperpigmented macules.Methods:This study was conducted on 90 patients diagnosed with DM and their age and sex matched controls who were referred to the Departments of Endocrinology at Babol University of Medical Science in Northern of Iran from January 2013 to December 2015. All demographic data including age, gender, occupation, family history of DM, estimated average sun exposure and presence of skin lesions were collected and analyzed.Results: Presence of SL was significantly higher among patients with DM compared to controls (61.9% vs 33.6%, P<0.001). After adjusting for age, sex and sun exposure rate, results indicated that DM was independently associated with the presence of SL (p=0.002). Stratifying patients based on gender, indicated that DM was significantly associated with SL in females (p=0.03), but not in male patients (p=0.06).Conclusion: The findings of the present study indicate that DM is an independent risk factor for the occurrence of SL lesions. These findings could represent a novel association between DM as a chronic oxidation state and SL as an early sign of aging.