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Let (A1, A2, A3) be a triple of nonempty convex subsets of a metric space Ω. In this paper, we determine optimal problems of the best proximity pair by proximal normal structure between two sets A1 and A2 with the help of a third set A3 and we find some necessary and sufficient conditions for existence these optimal problems. Also, we provide an example to illustrate the convergence behavior of our proposed results. [ABSTRACT FROM AUTHOR]

Graph theory is a useful tool to study the properties of algebraic structures. Here we are going to employ this tool to study nominal sets. To do so, we employ the freshness relation to construct certain graphs so-called fresh-graph, due to the key role of freshness relation in obtaining these graphs. We then investigate the properties of these graphs to determine some properties of nominal sets. [ABSTRACT FROM AUTHOR]

Electromagnetic absorbers based on ultra-thin metallic film are desirable for many applications such as plasmonics, metamaterials, and long-wavelength detectors. A metallic film will achieve a maximum 50% of electromagnetic wave absorption, frequency independent, at a thickness defined by its conductivity, typically in the sub-Angstrom range for good metals if bulk conductivity is maintained throughout. This makes it extremely difficult to obtain substantial absorption from thin metal films, in contrast to 2D materials such as graphene. Luckily, however, from a practical point of view, metal conductivity is drastically reduced as the film becomes sub-100 nm, to make it a race between the thinnest possible metal thickness experimentally achievable vs the conductivity reduction. Here, we demonstrate a near-50% absorption at a gold film thickness of 6.5 nm, with conductivity much reduced from the bulk value, down to the range of 106 Siemens per meter. Studying the effect of the substrate thickness, we found that the common cover glass, with its thickness much smaller than the wavelength, achieves symmetric absorption of 44%, implying that a pseudo-free-standing limit is achieved. Our work may find applications in infrared sensing as in bolometers and biomedical sensing using microwaves. [ABSTRACT FROM AUTHOR]

In this paper, we introduce a new class of algebras satisfying certain conditions which has been named power algebras and we prove some fixed point theorems for a new class of contractions. We give new conditions for the existence and uniqueness of fixed points for this new class of mappings which are not a contraction in the usual algebra. Also, we introduce a new iterative algorithm for fixed-point problems in a Banach algebra. This results improve and extend the corresponding conclusions of the Ishikawa algorithm under weaker conditions and lead to stronger results. In conclusion, we give an application to nonlinear integral equations. [ABSTRACT FROM AUTHOR]

Date palm fiber bundle includes lumens in solid region, which present low thermal conductivity than that of fiber bundle. In this work, the transverse thermal conductivity of date palm fiber bundle was determined by numerical software to investigate the relation between the bundle fiber and the solid region thermophysical properties. Therefore, the results determined from the numerical investigation were compared to the analytical model to prove the numerical model developed in this study. In this context, numerical simulation of thermal conductivity was performed by the numerical finite element method by COMSOL software. To verify the developed models, the bundle fiber and solid region thermal conductivity relation were determined. Quadratic and Cubic polynomial expressions, were used to study the influence of the normalized conductivity of the bundle fiber and the solid region of the composite material and to evaluate the composites thermal conductivity. Influence of lumen on the thermal conductivity was also investigated in this work. The results indicate that the bundle fiber thermal conductivity is much less than that of the solid region thermal conductivity. This one depends on pore dimension, but not on distribution and shape of pore. The numerical results obtained from the model developed in this study are compared with analytical model to validate this model. Finally, a sensitivity analysis was conducted with the models to investigate how changes in the values of important variables, such as thermal conductivity and volume fraction of the constituent, can affect the effective thermal properties of the composite. [ABSTRACT FROM AUTHOR]

Summary: Regulatory T (Treg) cell therapy is a promising approach for immune tolerance induction in autoimmunity conditions and cell/organ transplantations. Insufficient isolation yields and impurity during downstream processes and Treg instability after adoptive transfer in inflammatory conditions are major limitations to Treg therapy, and indicate the importance of seeking a valid, reliable method for de‐novo generation of Tregs. In this research, we evaluated Treg‐like cells obtained from different Treg differentiation protocols in terms of their yield, purity and activity. Differentiation was performed on naive CD4+ cells and a naive CD4+/Treg co‐culture by using three different protocols – ectopic expression of forkhead box protein P3 (E‐FoxP3), soluble transforming growth factor β (S‐TGF) and small molecules [N‐acetyl puromycin and SR1555 (N‐Ac/SR)]. The results showed that a high yield of a homogeneous population of Treg‐like cells could be achieved by the N‐Ac/SR method under a T helper type 17 (Th17)‐polarizing condition, particularly interleukin (IL)‐6 and TGF‐β, when compared with the E‐FoxP3 and S‐TGF methods. Surprisingly, SR completely inhibited the differentiation of IL‐17‐producing cells and facilitated Treg generation in the inflammatory condition and had highly suppressive activity against T cell proliferation without Treg‐specific demethylase region (TSDR) demethylation. For the first time, to our knowledge, we report the generation of efficient, pure Treg‐like cells by using small molecules during in‐vitro inflammatory conditions. Our results suggested that the N‐Ac/SR method has several advantages for Treg generation when compared with the other methods, including a higher purity of Tregs, easier procedure, superior suppressive activity during the inflammatory condition and decreased cost. [ABSTRACT FROM AUTHOR]

Nowadays, a large number of power conversion applications is commonly based on DC/DC converters with high voltage boost capability. Different voltage-boosting techniques have been reported in the literature. Each technique has its own merits and demerits depending on the application, cost, complexity, power density, reliability and efficiency. To meet the growing demand for such applications, new power converter topologies are continuously being proposed. This paper focuses on a novel hybrid boost converter, which combines the conventional boost (CB) and the quadratic boost (QB). This new topology allows the extension of the output voltage gain and the duty cycle range regarding to the original topologies. Thus, it ensures high conversion voltage ratio for almost duty cycle values. Consequently, it has two working modes, one as QB mode and the other one as CB mode. In order to verify the performance of the proposed topology, several simulations have been carried out under Matlab/Simulink environment for both QB and CB modes. The well-known P&O algorithm was implemented into a FPGA (Field Programmable Gate Array) board in order to verify experimentally the designed hybrid boost. Experimental results confirm the convenience of the proposed topology for tracking the maximum power point in photovoltaic systems. [ABSTRACT FROM AUTHOR]

We are going to study best simultaneous approximation preserving maps in a conditionally complete lattice Banach space X with a strong unit. Also we develop a theory of best simultaneous approximations for closed upward sets. [ABSTRACT FROM AUTHOR]

Oxidative stress is believed to be a major factor for the onset of Parkinson’s disease (PD). In this study, we have investigated oxidative status in transgenic Drosophila model of PD. Our results revealed elevated levels of reactive oxygen species (ROS) and lipid peroxidation (LPO) in A30P and A53T α-synuclein PD model flies compared to control. We have demonstrated for the first time the ameliorating potential of natural antioxidants characterized from the roots of Dh in A30P and A53T α-synuclein PD model flies. Feeding of transgenic flies with aqueous Dh root extract for 21 days significantly improved their climbing ability and circadian rhythm of locomotor activity which was associated with reduction in levels of ROS and LPO and enhancement in the activities of catalase (CAT) and superoxide dismutase (SOD). Dh protected against paraquat (PQ) sensitivity in α-synuclein transgenic flies and delayed the onset of PD-like symptoms which appears to be mediated by suppression of oxidative stress. [ABSTRACT FROM AUTHOR]

Although fuzzy set theory and sheaf theory have been developed and studied independently, Ulrich Hohle shows that a large part of fuzzy set theory is in fact a subfield of sheaf theory. Many authors have studied mathematical structures, in particular, algebraic structures, in both categories of these generalized (multi)sets. Using Hohle's idea, we show that for a (universal) algebra A, the set of fuzzy algebras over A and the set of subalgebras of the constant sheaf of algebras over A are order isomorphic. Then, among other things, we study the category of fuzzy acts over a fuzzy semigroup, so to say, with its universal algebraic as well as classic algebraic definitions. [ABSTRACT FROM AUTHOR]

In this paper, an effective operation of standalone hybrid photovoltaic (PV) system is proposed by implementing a management program via control strategy. The system is composed of photovoltaic modules, a liquid petroleum gas (LPG) fired generator and electrochemical batteries. The system configuration can solve problems that affect the quality and reliability of power supplies. This document includes the state of the art work carried out so far in the field of hybrid energy systems, including the study and evaluation of control methods. This paper focuses on the design and implementation of an electronic control module and optimal energy management in hybrid energy systems, using real weather data and load profile. The results have shown a reliable behavior of the control system and a good robustness to perturbations. [ABSTRACT FROM AUTHOR]

In this paper, we give new common fixed point theorems on cone metric space. [ABSTRACT FROM AUTHOR]

Purity and equational compactness play a role at least in the Theories of Modules, Acts, Model, and Category. Adámek and Rosický have studied them categorically, Rothmaler model-theoretically, and some authors, including Banaschewski, Gould, and Normak have studied these notions on G-acts. We take both the group G and the set A in the definition of a G-act to be sheaves and study equationally compact G-sheaves. We get different kinds of equationally compact G-sheaves, study them and their interrelations, give some conditions for their proper behavior, and generalize some of the existing results. [ABSTRACT FROM AUTHOR]

In this paper, we obtain some results on best f-approximation in quotient spaces of vector spaces and determine under what conditions f-proximinality can be transmitted to and from quotient spaces. Also, in conclusion, we consider the relationship between f-approximation subsets and linear functionals on X. [ABSTRACT FROM AUTHOR]

A calorific energy is generated during the photovoltaic conversion of the solar module, which increases the temperature of the cell and will cause a fall in its electric output. This phenomenon is, on one hand, due to the partial unabsorptive solar radiation, which constituted the origin of the cell's heating, and on the other hand, due to the Joule effect caused by the passage of the photo-electrical current generated in the external circuit. This heating, harmful for the photovoltaic cell output, involved many research efforts to limit its effects by evacuating this heat. There was also the idea to exploit this phenomenon by the combination of the photovoltaic module with a thermal system to form the photovoltaic thermal (PVT) hybrid collector, which will generate, at the same time, electricity and heat. In this paper, the design of a new type of PVT collector is described through its numerical modeling and experimental study. This novel collector constitutes a new technical approach to maximize the total output of conversion with lower cost compared to the traditional hybrid collectors. [ABSTRACT FROM AUTHOR]

Nowadays purity plays a role in at least four branches of mathematics: Module Theory, Theory of Acts over semigroups, Model Theory, and Category Theory. Adámek and Rosciký have studied these notions categorically, and Rothmaler model-theoretically. Some authors including Banaschewski, Gould, and Normak have studied purity on G-acts, acts over a monoid or a group G. In this paper we take both the group G and the set A in the definition of a G-act to be sheaves (multigroups and multisets) over a topological space X to get the category G-ShX of G-sheaves, and mainly study different types of essentiality with respect to the different classes ℳ of pure monomorphisms in G-ShX. We give some necessary and sometimes sufficient conditions for the different types of essentiality. We will also see that these notions of essentiality are local, in the sense that an ℳ-monomorphism f is ℳ-essential if and only if there exists a cover of disjoint open sets of X such that the restriction of f to every component is essential. [ABSTRACT FROM AUTHOR]

Among the large number of photovoltaic applications, we are interested in the cathodic protection; it's one of the most widely used methods for corrosion prevention, mainly in the oil and gas industries. In this paper, we report on our study of the design of a voltage regulator with variable output and maximum power point tracker (MPPT) for solar photovoltaic cathodic protection. The system is based on two microcontroller controlled DC/DC converters. The first one is a buck used to match the maximum power point voltage of the solar panel to the battery charging voltage; and the second one is a buckboost used between the batteries and the load in order to adapt the regulator for all cases of the cathodic protection systems. Usually, cathodic protection systems are working with constant current output, which is the necessary condition to procure immunity voltage to the structures, thus preventing corrosion from occurring. In our case, the system is carried out by an automatic adjustment of the output voltage of the adapter, which is the buck-boost DC/DC converter, by means of the microcontroller by generating the required duty cycle by way of its pulse width modulation (PWM) output port. In this paper, a study of an optimum design of this voltage regulator with variable output for solar photovoltaic cathodic protection has been carried out. [ABSTRACT FROM AUTHOR]

Abstract: This paper deals with design of hybrid energy system consisting of wind and photovoltaic with battery storage. A diesel generator is added to ensure continuous power supply and to take care of intermittent nature of wind and photovoltaic. The paper reports results of the technical–economic optimization study of photovoltaic/wind/diesel hybrid with battery storage in Algeria. The primary objective of this study is to estimate the appropriate dimension of stand-alone hybrid photovoltaic/wind/diesel with battery storage that guarantee the energy autonomy of typical remote consumer with lowest cost of energy. A secondary aim is to study the impact of renewable energy potential quality on the system size. The optimum dimensions of the system are defined for six sites in Algeria. In this context, a complete sizing model is developed in Matlab/Simulink V.6.5, able to predict the optimum system configuration. The simulation results indicate that the hybrid system is the best option for all the sites considered in this study. Thus, it provides higher system performance than photovoltaic or wind alone. It s shown that the principal advantage of photovoltaic/wind/diesel hybrid with battery storage are used all together, the reliability of the system is enhanced. The economic analysis has resulted in the calculation of kWh cost of energy for different types of resources and optimized cost of hybrid energy system. It s revealed too that the energy cost depends largely on the renewable energy potential quality. So, our objective for the optimization parameters is not the production cost but the offered service. [Copyright &y& Elsevier]

Abstract: We present a methodology to analyze the performance of a photovoltaic system of pumping installed in an isolated site at Ghardaïa (southern of Algeria). A computer program which simulates the electric operation of the system (irradiation and production of water) on the hourly basis was developed while being based on the data of irradiation of the site of year 2005, measured with a step of 5min. This work allows to evaluate the economic interest of the system which will have to satisfy an average daily volume of 60m3 throughout the year compared to another very widespread energy system in the area, the diesel genset (DG), by using the method of the life cycle cost (LCC). Considering the economic realities of the Algerian market where the price of the fuel is very low, it makes it difficult to other energy processes to emerge. [Copyright &y& Elsevier]

Abstract: The storage of energy in batteries is a cause of the failure and loss of reliability in PV systems. The battery behavior has been largely described in the literature by many authors; the selected models are of Monegon and CIEMAT. This paper reviews the two general lead acid battery models and their agreement with experimental data. In order to validate these models, the behavior of different battery cycling currents has been simulated. Results obtained have been compared to real data. The CIEMAT model presents a good performance compared to Monegon’s model. [Copyright &y& Elsevier]

The distribution of energy consumption by sector shows that the consumption rate of the building is very high. On a worldwide scale, the rate varies between 30 and 40%. In Algeria and according to the energy balance published by the Ministry of Energy, the residential household sector represents of about 42% of the total energy consumption. The main objective of this paper is to study the performance of the grid-connected photovoltaic system and the energy balance in the residential building. A case study is applied in the northern region of Algeria. The photovoltaic system supplies the house with electricity during the sunny days, and during the night or the cloudy-days, the house is powered by grid. The calculation of energy performance is based on the optimization, rationalization and saving energy approach. This takes into account the energy profiles of residential homes, real data and meteorological conditions. The results show clearly that the use of saving energy and grid-connected photovoltaic system allows a positive annual electricity balance of the studied residential house. The PV system generated 67.6% of the overall energy used in the house. Only, 33.4% are purchased from the grid. An energy positive balance of 2 kWh/day is observed. [ABSTRACT FROM AUTHOR]

Introduction With regard to disaster proneness of Islamic Republic of Iran, considering the capacity of all stakeholders may lead to correct use of resources and facilities and decrease or control the destructive effects in disaster affected areas. Methods In a library based review we found out, saving life is the most important factor in health management and that the disaster management must focus on three phases. Pre-event Management of this phase includes situational analysis (structural and non-structural), surveillance, adapting standards, communication, information and warning systems, public education and organising local or country wide manoeuvres for testing the response mechanisms. Event Includes triage, reinforcement of rescue and relief capacities, evacuation, financial and human supports in the community and collaboration with other stakeholders such as the Ministry of Interior and other subcommittees, local or collaborating health facilities in the field or nearby, medical and residential centres, mass media and if indicated, field hospitals also expert human resources are important for medical management in this phase. Post-event It's the longest phase includes referring survivors to rehabilitation centres, evaluating mental and social needs of them and assist communication between the remainders and social support centres and assessing the response programs. Discussion Public awareness by capacity building is necessary for decreasing destructive outcomes in stressful situations. Disaster prevention, mitigation & preparedness are more important than response in achieving the goals and objectives of vulnerability reduction. Disaster response alone is not sufficient as it yields only temporary results at a very high cost. [ABSTRACT FROM PUBLISHER]

Injuries are one of the most important challenges in public health with great socioeconomic burden especially in developing countries. In Islamic Republic of Iran, road traffic injuries are known as the first cause of burden and the second cause of death in all age groups. According to the 92 nd article of fourth national socio-economic and cultural developmental law, the Ministry of Health and Medical Education is responsible for immediate and free of charge medical coverage for road traffic victims referred to the hospitals and healthcare facilities. This law passed 2005. Financial resources for road traffic victims services are provided from vehicle insurance fees. It means that 10% of the compulsory third party insurance premiums are transferred to the ministry of health to compensate the costs related to medical care of the injured patients. Thus, road traffic injuries are no longer a cause of catastrophic medical care cost in our country. This might be a step towards accounting the social determinants of health because after passing this law, although the number of road traffic hospital admitted injured increased (from 550 714 to 718 000) but the number of road traffic death increased (from 22 918 to 23 362). This shows the role of health sector regarding better health equity and improved access. [ABSTRACT FROM PUBLISHER]

Introduction In our country there was an ancient Wednesday eve festival during the last Wednesday evening of each year which included creating small fire and jumping over it with making good health wishes. Unfortunately for using fire crackers nowadays the real feature of this night has become similar to a war scene. Methods Data was collected during 21 April 2009 till 20 March 2009 and carried out from all over the country. It was assessed and analysed in the Violence and injury prevention department of the Ministry of health and medical education. Different types of injuries were classified and correlated with age, sex, education, out come, activity while injury occurred and place or field of occurrence. Result Overall, 1817 cases were registered in 41 medical universities. The most common type of injury was first degree burning (25.2%), followed by abrasion and corrosion (24.6%), and second degree burning (13.3%). The most common place for injuries was road, street and highways (80.2%) followed by home and around it. Overall, the commonest age of injures was 15–19 (25.8%) followed by 20–24 (20.5%). Males were more likely to be injured than female (83.2 vs 16.8). Hands (43.3%) were the most common injured site in the Wednesday eve festival followed by eyes (24.5%). Unfortunately three dead and four disabilities were reported. Conclusion Preventive interventions most focus on pupils as the most vulnerable group and the schools as the most accessible field in Iran. [ABSTRACT FROM PUBLISHER]

Among a large number of photovoltaic applications, we are interested in the cathodic protection. It is one of the solutions used for the structures subjected to corrosion, mainly in oil and gas industries. In this work, optimum design sizing and system description are presented. Based on the design of a solar photovoltaic powered minicathodic protection system, a standard configuration of the photovoltaic system using a combination of four panels (two in series and two in parallel), has been derived. This standard size option must be matched at any cases of the cathodic protection station. For this purpose, an adaptive circuit, which is a voltage regulator with variable output, has been developed. Usually, cathodic protection systems work with constant current output, which is the necessary condition to procure immunity voltage of the structures against corrosion. The major difficulty to achieve this goal is the variations in the surrounding medium resistivity. To overcome this difficulty, several systems of control and regulation intended for cathodic protection system powered by photovoltaic energy have been designed and discussed. In our case, we propose an adaptive adjustment of the buck-boost converter output voltage by means of the microcontroller pulse width modulation output. In this paper, a complete design of the adaptive cathodic protection system using photovoltaic energy is carried out. [ABSTRACT FROM AUTHOR]

Objectives: There are few reports on epidemiological patterns of injury and injury-related mortality in developing countries. This study aimed to report the epidemio!ogy of injuries and poisonings in emergency departments in Iran. Study design: Retrospective study using available data from 20 March 2005 to 19 March 2008. Methods: Recorded Injury Surveillance System (ISS) data including demographics, place of residence, type of injury, and outcome during emergency department stay were extracted from the databank of the national ISS and included in the final analysis. Results: In total, 2,991,624 emergency department admissions due to injury were recorded at university hospitals during the study period. According to the national census in 2006, Iran had a population of 70,472,846, so the injury admission rate to university hospital emergency departments was 1.4%/year in Iran. The mean age of the patients was 26.5 [standard deviation (SD) 16.9] years, and 72.7% of the cases were male. The most common cause of injury was road traffic accidents (RTAs) (31.9%), followed by hit (25.5%) and falls (10.9%). Intoxication was associated with 5.3% of all injuries. The overall emergency department mortality rate was 0.6%. Of those who died, the mean age was 32.6 (SD 21.1) years. All fatal injuries, except burn injuries, were more common in males. Intoxication-related deaths occurred in 3.8% of cases. In patients aged <13, 13-65 and >65 years, hit (28.2%), RTAs (34%) and RTAs (27.9%) were, respectively, the most common causes of injury. In all age groups, RTAs were the most common cause of death. Conclusions: This study determined the epidemiology of injuries and poisonings in emergency departments in Iran. The mortality rate in this study was low in comparison with other research, which may be explained in the context of inappropriate prehospital or interhospital care in Iran. This finding can be employed to formulate targeted preventive strategies based on the incidence of the more common types of injury. [ABSTRACT FROM AUTHOR]

This work has two main objectives. The first objective is to carry out a statistical comparison of specific models for estimating monthly mean daily and hourly global and diffuse irradiations on a horizontal surface from the monthly average per day of the main meteorological data and to recommend the most accurate models to be used for estimating solar radiation in sites belonging to the Algerian climate areas represented by each of the three sites presented in this work. The second objective is to propose a Simulink program where the methodology allows for reconstituting daily and hourly monthly mean horizontal solar radiation data. From the 10 global radiation models proposed in several journal papers, Rietveld’s, Garg et al ’s and McCulloch’s relations are retained, respectively, for estimating the monthly mean daily global ratio for Adrar, Bouzareah and Ghardaia sites and Page and from the nine retained diffuse relations, Page’s, Liu et al ’s and Erbs et al ’s relations are used, respectively, for the same sites for calculating the monthly averages per day of diffuse irradiation. On the other hand, the models of Jain and Liu et al are, respectively, recommended for the reconstitution of the monthly averages per hour of the global and diffuse irradiations. However, the obtained results are used to develop a Simulink program which can be used in the estimation of long-term performance of flat plate solar radiation systems. [Copyright &y& Elsevier]

Abstract: Efficient visible photoluminescence (PL) is obtained from a hydrocarbon (CHx) layer coated porous silicon (PS). PL and its dependence upon aging have been investigated. Fourier Transform Infrared (FTIR) spectroscopy has been used to study the bonding characteristics at the surface before and after the CHx deposition. The enhancement of the PL properties and its features with aging time are explained by the FTIR spectroscopy studies. In this paper, we present experimental evidence that emphasises the role that surface recombination plays in the luminescence of PS. [Copyright &y& Elsevier]

Abstract: A gas sensor utilizing a porous silicon layer and a thick film printing technique, instead of thin film deposition and photolithographic methods for fabricating such a device, is presented. The contact structure consists of a printed silver metal grid on the top of the porous silicon surface and an aluminium ohmic contact at the bottom, which were formed by a screen-printed metallization process. Freshly prepared porous silicon (PS) surfaces have been modified with organic molecules (CH x groups) in a thermal process in order to replace the hydrogen termination by monolayers attached to the surface through Si–C bonds. In this work, we report the experimental results of a porous silicon based sensor whose contacts were treated at different temperatures, ranging from 200 to 750°C, and the effect of this thermal process on the reorganization of the PS bond configuration. [Copyright &y& Elsevier]

Introduction Nearly 1 million people worldwide commit suicide each year, with anywhere from 10 to 20 million suicide attempts annually. Suicide is the process of purposely ending one's own life which shatters the lives of family and friends. Methods In a 7 year survey from 21 March 2002 to 20 March 2009 all hospitals admitted suicidal cases from all hospitals of Iran medical university in Tehran were included in our study. The cases were both from public and private hospitals. Results Overall 12 224 cases were admitted during 7 years, in most cases there was no single or clear reason for why he decided to suicide. The most common type of suicide was drug abuse (taking high doses of legal or illegal drugs) and the less was electrical shock. The most common age was 21–30 years old followed by 16–20. Females attempted and dead much more often by means of suicide than do males (60% vs 40%). Single had more suicidal behaviours than married. Recommendation There are two central components of successful prevention programs. The first is case-finding; means to find individuals who are at risk, referring them and making sure they get appropriate care. The second is risk reduction or primary prevention by reducing the risks for suicide and suicidal behaviour in the general population. Community prevention efforts should focus on primary prevention from childhood because behaviours that contribute to the leading causes of morbidity and mortality among adults often are established during childhood. [ABSTRACT FROM PUBLISHER]

Abstract: This work is performed to investigate the effect of using different sun tracking mechanisms on the flat plate photovoltaic system performances and the main parameters affecting the amount of their electrical energy output as well as those affecting their gains compared to the traditional fixed photovoltaic systems. To this end, five configurations of sun tracking systems and two traditional fixed panels have been considered. The sun tracking systems effect on the PV system performances is improved by using the hourly data collected over 18days for different seasonal sky conditions. The daily cumulative electrical energy produced by the different systems have been quantified separately for each sky state and the corresponding electrical gains have then been compared to those experienced with two traditional fixed photovoltaic systems. It is found that for a completely clear day, the highest obtained gains are those related to the two-axis sun tracker systems, which decrease gradually from the inclined to the vertical rotating axis when the same optimum slope is applied and from the seasonal to the yearly optimum slope if the same rotating axis is considered. On the other hand, for the partially clear days, the gain amounts are mainly dependant on the clearness index and on the seasonal variation of day length values. For a completely cloudy day, the results show that all considered systems produced closely the same electrical energy and the horizontal position of the photovoltaic panel presented the best performance. [Copyright &y& Elsevier]

This study was undertaken to define the prevalence of the upper Gastrointestinal (GI) lesions, dyspeptic symptoms, H.pylori infection, and the impact of duration of dialysis on upper GI symptoms and lesions of children with End-stage renal disease. We studied 69 children with ESRD who were under regular hemodialysis therapy in our department. The age of the patients were between 4-18 years (mean: 11.3). 57(82.6%) of 69 patients had GI symptoms and 12(17.4%) were symptom free, the prevalence of each symptom in 57 symptomatic children was as follows: anorexia 48(84.2%), nausea/vomiting 39 (68.4%), belching/heartburn 20(35%), abdominal distention 15(26.3%), and epigastric pain 8(14%). 65(92.4%) of 69 patients with ESRD had pathologic lesions and the most common lesion was gastritis .There was no case of gastric angiodysplasia in our patients. 15(21.7%) of 69 patients had H. pylori infection. The prevalence of H.pylori infection in non-uremic children with upper GI symptoms is about 27% in our pediatric gastroenterology department, so there was no significant difference in prevalence of H.pylori infection between uremic and non-uremic children in our study (p value = 0.4735). There was no significant relationship between duration of dialysis and dyspeptic symptoms or upper GI lesions (p values were 0.8775 and 0.7435, respectively). Conclusions: Upper GI disorders are very common in children with ESRD, even when they have no upper GI symptoms, the most common lesion is gastritis. The prevalence of H.pylori infection is not different between children with ESRD and non-uremic children with upper GI symptoms, and duration of hemodialysis therapy has no significant effect on prevalence of GI symptoms and lesions. [ABSTRACT FROM AUTHOR]

Abstract: The overall efficiency of photovoltaic (PV) systems connected to the grid depends on the efficiency of direct current (DC) of the solar modules to alternate current (AC) inverter conversion. The requirements for inverter connection include: maximum power point, high efficiency, control power injected into the grid, high power factor and low total harmonic distortion of the currents injected into the grid. An approach to power factor control and reactive power regulation for PV systems connected to the grid using field programmable gate array (FPGA) is proposed. According to the grid demands; both the injected active and reactive powers are controlled. In this paper, a new digital control strategy for a single-phase inverter is carried out. This control strategy is based on the phase shift between the inverter output voltage and the grid voltage, and the digital sinusoidal pulse width modulation (DSPWM) patterns, in order to control the power factor for a wide range of the inverter output current and consequently the control and the regulation of the reactive power will be achieved. The advantage of the proposed control strategy is its implementation around simple digital circuits. In this work, a simulation study of this strategy has been realized using Matlab/Simulink and PSIM. In order to validate its performance, this control has been implemented in a FPGA. Experimental tests have been carried out demonstrating the viability of this control in order to control the power factor and the injected power into the grid. [Copyright &y& Elsevier]

Abstract: The optimal design of the renewable energy system can significantly improve the economical and technical performance of power supply. In this paper, the technical-economic optimization study of a stand-alone hybrid PV/wind system (HPWS) in Corsica Island is presented. Therefore, the primary objective of this study is to estimate the appropriate dimensions of a stand-alone HPWS that guarantee the energy autonomy of a typical remote consumer with the lowest levelised cost of energy (LCE). A secondary aim is to compare the performance and the optimal sizing of two system configurations. Finally, to study the impact of the renewable energy potential quality on the system size, the optimum dimensions of system are defined for five sites in Corsica Island. In this context, a complete sizing model is developed, able to predict the optimum system configuration on the basis of LCE. Accordingly, an integrated energy balance analysis is carried out for the whole time period investigated. The simulation results indicate that the hybrid system is the best option for all the sites considered in this study, yielding lower LCE. Thus, it provides higher system performance than PV or wind systems alone. The choice of the system configuration type affects the state of charge variation profile, especially at low wind potential sites, while the system size and the LCE are significantly influenced. It is shown that the LCE depends largely on the renewable energy potential quality. At high wind potential site, more than 40% of the total production energy is provided by the wind generator, while at low wind potential sites, less than 20% of total production energy is generated by the wind generator. [Copyright &y& Elsevier]

Abstract: We present results on the photoluminescence (PL) properties of porous silicon (PS) as a function of time. Stabilization of PL from PS has been achieved by replacing silicon–hydrogen bonds terminating the surface with more stable silicon–carbon bonds. The composition of the PS surface was monitored by transmission Fourier transform infrared (FTIR) spectroscopy at intervals of 1 month in ageing time up to 1 year. The position of the maximum PL peak wavelength oscillates between a blue-shift and a red-shift in the 615–660nm range with time. [Copyright &y& Elsevier]

Abstract: The most spectacular feature of porous silicon (PS) is its ability of emitting very intense visible light at room temperature and to use this light emission as a sensor signal. In this paper, we report the sensitivity of porous silicon photoluminescence (PL) to carbon dioxide and propane gases. A hydrocarbon film has been applied to PS surface to enhance its luminescence since a complete surface passivation is important to suppress or reduce non-radiative recombination centres. The operation sensor effect is based on the variation of the photoluminescence of the CH x /PS region due to the interaction with gaseous substances. Presence of carbon dioxide reduces the PL intensity while propane provokes an opposite behaviour. The PL quenching phenomenon leads itself to interesting optical sensor applications. The annealing effect on the photoluminescence of a p-type CH x /PS has been investigated. The orange light disappears and an intense blue light is obtained. Moreover, the effect of this treatment on the PL response of porous silicon in presence of CO2 and propane gases has also been studied. [Copyright &y& Elsevier]

The article presents a study which surveyed suicide attempts and suicide in Iran based on the epidemiological data from the national injury surveillance system (ISS) from March 20, 2005 to March 19, 2008. Some of the ISS data used in the study, include demographics, place of residence and type of trauma. It relates the rate of suicide attempts and suicide in hospital emergency departments (EDs) during the period. The study has revealed that females accounted for 53% of the suicide attempts.

Introduction: Magnetized water has made many improvements in industry, agriculture and medicine. However its utilization in medicine still remains controversial. In this study we aimed to investigate the effects of magnetized water on fertility and height of epithelial cells in pre- implantation stage endometrium and fallopian tube in female mice. Materials and Methods: Eighty female NRMI mice were randomly divided into two groups: the control group drank no magnetized water and the experimental (case) group drank magnetized water for 2 weeks. Female mice were superovulated and mated with male mice. At pre-implantation time samples of endometrium and fallopian tube were obtained and after processing, the height of epithelial cells was measured by light microscope equipped with cell measurement software. Results: Data analysis showed a significant increase in the mean number of corpus lutea and the height of epithelial cells in fallopian tube comparing the case with the control group (p<0.01, p<0.05 respectively) whereas endometrium epithelial cells of the case group showed insignificant increase in height, in compare with the control group (p>0.05). Conclusion: Our results suggest that magnetized water can improve fertility indices in mice by increasing the number of corpus lutea and the height of fallopian tube epithelial cells. Therefore magnetized water, along with other methods, can be used to increase the success rate of fertility especially in assisted reproductive technology. [ABSTRACT FROM AUTHOR]

Background This cross sectional study was carried in the EOC of Ministry of Health & Medical Education, for road traffic injuries. The aim of this study was showing the role of health sector in decreasing road traffic injuries mortality as a public health challenge according to the forth developmental agenda. Materials and Methods The data were gathered in the Disaster and Emergency Management Centres of 41 medical universities in Iran and was analyzed in the Eoc of Ministry of Health using SPSS version 12. Result Increasing the number of prehospital emergency centres per population (25% in 2006 comparing to 2005, and 21% in 2007 comparing to 2006), decrease in the number of death per fatal crashes (4 in 2006, in comparison with 1.3 in 2007), 43.1% decrease in the number of death at the scene and 33.8% decrease in the number of death during hospital transit in 2007 in comparison to 2005, and decrease in arrival time of EMS from 10 min for urban missions in 2005 to 7 min in 2007 all are due to five basic managerial achievements in the Ministry of Health & Medical Education including planning, organising, staffing, leadership and control. Conclusion For decreasing road traffic injuries mortality and morbidity rate, holistic approach in the EMS management is needed, which target both human resources (staff and training) and physical resources (infrastructure, equipment and supplies). [ABSTRACT FROM PUBLISHER]