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In this paper, we simulated and designed an all-optical Fredkin gate. The proposed structure is very simple and compact. We used air holes with radii of 177 nm in a silicon slab waveguide in a square lattice with a lattice constant of a = 466 nm. First, we created input and output waveguides in the structure. After that, by imposing a non-linear ring resonator, we controlled the coupling of light. This ring is composed of doped glass with linear and non-linear refractive indices of 1.4 and 10–14 m2/w respectively. The results of the time analysis showed that the worst rising time of the proposed gate is 0.61 ps and hence is very fast. We set the parameters of the lattice in a way that the proposed device works on λ = 1550 nm. All of the mentioned features make this gate suitable for all-optical integrated circuits. [ABSTRACT FROM AUTHOR]

In this paper, by using the non-linear effects and also destructive and constructive interferences between waveguides, we have designed and simulated an all-optical full-Subtractor based on two-dimensional photonic crystals. The proposed Subtractor has a very simple structure which is composed of 33 × 31 silicon rods immersed in air in a square lattice and involves three input ports (bits) and an additional waveguide to exhaust the unwanted light. We imposed some defect rods to control the behavior of the light. The used non-linear material, is a doped glass with 1.4 × 10–14 m2/w non-linear refractive index which is very greater than the non-linearity refractive index of silicon, 3.46 × 10–20 m2/w. Since the proposed structure is very simple and compact, it can be applicable in optical integrated circuits and optical calculations. [ABSTRACT FROM AUTHOR]

In this research, we fabricated the electrospun nanofibers based on functionalized porous graphene (FPG), modified SBA-15 (SBA/CuO), Polyvinylpyrrolidone (PVP), and Polyacrylonitrile (PAN). FPG, SBA/CuO, and PAN concentrations, and applied voltage were optimized to fabricate the nanofibers with the best morphology. The average diameter of optimized nanofibers was obtained at 124 ± 41 nm. A series of characterizations, including FE-SEM, EDX, AFM, FT-IR, XRD, TG-DTA, tensile and contact angle measurements were employed to study the structure and morphology of nanofibers. We fabricated a Nano-filter from nanofibers to remove some water pollutants including methylene blue, malachite green, potassium permanganate, copper, lead, and cadmium ions. The filtration performance of the proposed Nano-filter was examined under the optimum conditions (concentration, volume, and pH) for each of the water pollutants (R> 97%). The results of Nano-filter recycling showed that it could be reused up to 5 times with more than 90% efficiency. Experiments have demonstrated that Nano-filter has ideal performance in the removal of dyes and metal ions from factory wastewater. Besides, the static and dynamic adsorption capacities were explored, where methylene blue (112 mg/g) and lead ions (131 mg/g) had higher static states were higher than other dyes and metal ions. [Display omitted] • A novel nanofiber was synthesized and characterized. • Use nanofiber as a membrane to filtration of water pollutants. • A simple method of filtration by the vacuum pump. • High filtration performance in the removal of heavy metals and dyes. • High dynamic and static capacities adsorption for heavy metals and dyes. [ABSTRACT FROM AUTHOR]

Massive windings must be used for strong magnetic field applications, which results in low magnetic field uniformity. In this paper, a simple circular Helmholtz coil system is analyzed to identify the main causes of the problems, which arise for high intensity uniform magnetic field applications. Here, dominant deformations of the circular solenoid winding cross-section shape and its dimensions effects on the generated magnetic field and its uniformity are analyzed. These analyses can be applied to the modified Helmholtz coil and multi-axial systems, as well. The system dimensions are optimized and normalized to easily scale the given results for any desired uniform magnetic field and workspace without doing further laborious calculations. The optimized dimensions increase the magnetic field uniformity in a large portion of the available workspace and realize the desired magnetic field at the center of the system. Also, the necessary conductor mass and the total electrical power are reduced. To verify the given analyses, two small-scale Helmholtz coil systems have been implemented and their generated magnetic fields and nonuniformities have been measured under a variety of conditions. [ABSTRACT FROM PUBLISHER]

Purpose: While several studies have reported a relationship between chronic daily headache (CDH) and different dietary patterns, no study has investigated the association between CDH and the dietary inflammatory index (DII). This study aims to hypothesize that a higher DII score (proinflammatory diets) is associated with higher odds of CDH. Design/methodology/approach: This cross-sectional study was performed using the baseline data of the Dena PERSIAN cohort study, including demographic information, body mass index, medical history, laboratory tests, sleep duration and blood pressure. The DII was computed based on the data collected by a valid 113-item food frequency questionnaire and a 127-item indigenous food questionnaire. The association between CDH and DII score was analyzed by simple and multiple logistic regression. Findings: Out of 3,626 people included in the study, 23.1% had CDH. The median DII was −0.08 (interquartile range = 0.18). People in the third and fourth quartiles of DII (proinflammatory diet) had a 20% (odds ratio: 0.80; 95% confidence interval: 0.65–1) and a 25% (odds ratio: 0.75; 95% confidence interval: 0.61–0.94) lower chance of having CHD than those in the first quartile, respectively. After adjustment for confounding variables, this association did not remain statistically significant (p > 0.05). Originality/value: Although the analysis conducted without adjustment for medical history showed a significant association between proinflammatory diet and reduced CDH, considering the diverse etiology of different types of headaches and the paucity of studies in this area, further studies are needed to investigate the DII score of patients by the type of headache, its severity and duration. [ABSTRACT FROM AUTHOR]

Resonant switched-capacitor converters have widely been used recently to increase conversion power density. The most significant drawback of these converters is voltage regulation problem when their input voltages vary in wide ranges. Here, a basic double voltage-ratio resonant switched-capacitor converter (SCC) is analyzed and simulated below its resonant frequency under the different operation modes to overcome this problem. The converter different parameters are calculated under both continuous conduction mode (CCM) and discontinuous conduction mode (DCM) conditions. The advantages and drawbacks of these operation modes are compared and the closed-loop control of the converter is also investigated based on the extended describing function approach. The given analyses demonstrate that the output voltage can be well-regulated under the CCM1 and DCM2 operation modes even when wide input voltage and load variations are applied. Besides, the DCM1 operation mode must be avoided when output voltage regulation is important. Based on the given analytical and experimental results, switching frequency varies in a reasonable range to regulate the output voltage. Also, faster transient responses, smaller output capacitor, and smaller resonant tank components can be used below the resonant frequency, as compared to the above resonant frequency, but lower efficiency value is achieved. The given approach has been extended to the other resonant SCCs as well. [ABSTRACT FROM PUBLISHER]

A resonant switched-capacitor converter (SCC) has been analyzed above its resonant frequency to realize zero-voltage switching (ZVS) and to overcome voltage regulation issue of SCCs even when wide input voltage and output power variations are applied. ZVS operation under the continuous conduction mode (CCM) conditions improves efficiency due to lower conduction and switching losses. It is more efficient than the widely used zero-current switching (ZCS) approach in recent years under the discontinuous conduction mode (DCM) condition. Because, switching losses dominant components are reduced in MOSFET-based converters under the ZVS not ZCS conditions. Also, it has been demonstrated that output voltage can be well regulated under the CCM operation when wide input voltage and load variations are used. When output voltage regulation is not the major issue, operating at fixed switching frequency higher than, but near to, the resonant frequency results smaller components, higher power density, and lower electromagnetic interference level, as compared to the constant voltage ratio DCM operation mode, widely used in recent years. Also, output voltage ripple has been calculated, in details, by considering parasitic components of the output capacitor. A 110–165 to 200 V SCC has been implemented in 206.6–402.5 kHz frequency range to deliver 100–500 W. Maximum and average efficiency values equal to 96.8% and 94% are achieved, respectively. [ABSTRACT FROM PUBLISHER]

Background: Distribution of Tuberculosis (TB) has a special template affected by geographic and social factors. Nowadays Geographical Information System (GIS) software is one of the most important and useful epidemiologic devise for identifying geographic areas and high risk population for infection by TB. Aim of this study was assessment of Tuberculosis distribution by GIS in Khuzestan province, Iran. Methods: In this retrospective cohort study, documents of 6363 TB patients identified in Khuzestan province at the beginning of 2005 until the end of the September of 2012 were assessed and sampling method was census. The data was gathered by TB-Register Center. TB incidence was evaluated by GIS maps according to climatic and vegetation with 1:25,000 scale. The data was analyzed in SPSS software and means plot and Independent's t-test, ANOVA with a significance level of less than 5% and Eta Correlation. Results: Spread of Tuberculosis in climatic and vegetation were plotted in GIS maps, cumulative incidence rate was calculated separately for each area. There was a statistical significant relationship between cumulative incidence rate of disease and climatic (P=0.017) and the Eta correlation coefficient was 0.379 (P=0.011). There was a statistical significant relationship between cumulative incidence rate of TB and vegetation (P=0.004) and the Eta correlation coefficient was 0.388 (P=0.188). Mean age and median age of patients were 39.3±18 and 35±6.5 years respectively. For women, mean age was 2.1 years older than men and this difference was statistically significant. (P=0.0001). Conclusion: The risk of TB infection is closely associated with the climatic and vegetation. So the risk of TB in extra-dry climate and vegetation of highland meadows is more than other areas. Special care and services to high-risk areas is recommended. [ABSTRACT FROM AUTHOR]

Background: Tuberculosis is still one of the main causes of mortality and disability in developing countries. Despite of socio-economic development of communities and controlling majority of communicable diseases, With respect to importance and high incidence of Tuberculosis in marginal provinces, the present study was aimed to assess the epidemiology of Tuberculosis. Methods: In this Descriptive-Analytical Retrospective Study, documents of 6363 patients diagnosed with TB in the beginning of March 2005 to the end of the September 2012 in Khuzestan province, Iran, by used census sampling size, were used. Demographic variables and other necessity data were recorded by TB-Register software and then these data were analyzed by SPSS 16.0 software and Chi-square and independent t-tests with a significance level of less than 5%. For comparison Tuberculosis incidence in consecutive years used by Poisson tests (with a significance level of less than 5%). Results: mean age of patients and median age of patients were 39.3±18 and 35±6.5 years, for women mean age was older 2.1 years than men and there was significant relationship to age (P=0.0001). Of all patients 75.7% were pulmonary tuberculosis, 2.7% were infected with HIV and 91.2% were new cases. Cumulative incidence in province was 148.84/100,000. Most prevalent in Non-pulmonary TB was Lymphatic glands. Poisson test showed that changing trends of TB incidence in study years was statistically significant (P<0.05). Conclusion: Increasing concurrent of HIV infection and TB and decreasing patients mean age (39.3±18) and median (35±6.5) in southwest of Iran has high prevalence. Screening, training and preventive activities for controlling of disease is highly recommended for the whole country and in margin provinces in particular. [ABSTRACT FROM AUTHOR]

LLC resonant converter is one of the most suitable circuit topologies that have been introduced for designing constant output voltage switched-mode power supplies. In this paper, a design procedure is introduced for using this converter as a wide output range voltage source. Unlike constant output voltage applications which need small converter inductance ratio and narrow switching frequency variations, for wide output range applications, large values of these parameters are needed simultaneously and should be optimized. Instead of minimizing the components stresses, leading to a great value of the inductance ratio, proper choice of the converter parameters resulting in a smaller inductance ratio has been done. Maximum value of the capacitor in parallel with the power MOSFETs drain-sources has been derived to realize the zero voltage switching operation in the converter inductive region. Soft switching is achieved for all power devices under all operating conditions. A prototype of the converter has been tested for different regulated output voltages (35-165 Vdc) under different loads (0-3 Adc) and input voltages (320-370 Vdc) for using an ion implanter arc power supply, with maximum efficiency value of 94.7%. Experimental results confirm the high performance of the wide output range LLC resonant converter even under the worst case conditions. [ABSTRACT FROM AUTHOR]

LLC resonant converter with significant resonant inductance is proposed for designing an adjustable wide-range regulated voltage source. Large resonant inductance increases output voltage adjustment range and conversion efficiency, particularly at light loads. Soft switching is achieved for all power devices under all operating conditions by choosing the dead time and maximum switching frequency properly and operating in the converter's inductive region. Using a power-factor-correction (PFC) converter reduces the resonant converter's output voltage dependence to the variations of the main ac input voltage. Thus, the compensation of the load variations and the wide-range adjustment of the regulated output voltage can be achieved by using small switching frequency variations. The proposed method has been used to implement an adjustable wide-range voltage source (35–165 V dc), as an ion implanter arc power supply. An almost flat efficiency curve with maximum value of 94% has been achieved for the converter. Its output current can change from no load to 3 A dc. [ABSTRACT FROM AUTHOR]

LLC resonant converter has been widely used in dc–dc converters. In this paper, optimum dead-time and maximum switching frequency of a wide-adjustable-range LLC resonant converter are investigated for realizing the zero voltage switching (ZVS) operation even under the worst-case conditions. Analyses demonstrate that these parameters depend on the converter inductance ratio and ratio of the converter resonant capacitor and the effective capacitance appeared in parallel with the drain–sources of the power MOSFETs. The necessary dead time for realizing the ZVS operation can be minimized by choosing the normalized maximum switching frequency, properly. Using the dead-time optimum value, soft switching is achieved for all power devices even under the worst-case conditions. Developed prototype of the converter has been tested under different loads (0–3 A dc) and input voltage conditions (320–370 V dc) to achieve a wide-adjustable-range output voltage (40–165 V dc). This dc–dc converter is used as an ion implanter arc power supply. The calculated optimum dead-time and maximum switching frequency are approximately equal to 184 ns and 205.7 kHz, for realizing the ZVS operation at the worst-case conditions. These parameters in the prototype are approximately equal to 195 ns and 203.5 kHz, respectively. [ABSTRACT FROM PUBLISHER]

LLC resonant converter has been used widely as dc-dc converter for achieving constant dc voltage. In this paper, an LLC resonant converter, by adding an inductance to its conventional topology and considering the rectifying stage stray inductances, is proposed for an adjustable wide range regulated current source (20-200Adc ) for using as ion implanter's filament power supply. The additional inductor increases output current adjustment range and efficiency, especially at light loads. Transformer's leakage inductances and rectifying stage stray inductances have been considered. Because of these inductances, the rectifier stage always works in continuous conduction mode, and its conduction angle is forced to be larger than π, and peak current of the rectifier stage and the output capacitor have been reduced effectively. Switching losses and electromagnetic interference noises have been reduced as well due to zero-voltage switching at the primary and secondary sides of the converter, and zero-current switching at its secondary side. Soft switching is achieved for all power devices under all operating conditions. A developed prototype of the converter has been tested under different load (2.5-12.5 m̱) and input voltage conditions (320-370 Vdc ) with maximum efficiency of 87%. Experimental results confirm high performance of the designed adjustable and regulated current source even under the worst-case conditions. [ABSTRACT FROM AUTHOR]

Background. Cystic echinococcosis is considered a public health problem that if left untreated can have dangerous consequences for the person. The disease is caused by Echinococcus granulosus sensu lato larvae. The main risk factors for this parasitic infection are habitat, direct contact with dogs, use of raw vegetables, and use of unwashed vegetables. The most important factors affecting the prevalence of HCD are economic, occupational, agricultural, educational, and factors related to public health and cultural habits of the general public in that geographical area. Objectives. The purpose of this study was to investigate the prevalence of the types of cystic echinococcosis genotypes (E. granulosus sensu stricto (G1-G3) and E. Canadensis (G6 and G7)) in livestock in Iran. Method. This systematic review was conducted, using Medline/PubMed, Scopus, Web of Sciences, and Google Scholar databases, to identify studies of cystic echinococcosis in animals published from 2010 to April 14, 2021. Finally, 28 studies were selected for meta-analysis, which was analyzed using Stata software version 14. The cystic echinococcosis prevalence with 95% confidence intervals of animals was synthesized using the random effect model. Heterogeneity was evaluated and in cases where the I 2 index was higher than 75%, subgroup analysis was performed according to the types of animals. Result. The highest prevalence of cystic echinococcosis infection was related to G1 genotype (P = 0.91 (95% CI = 0.84 , 0.97)) and the prevalence was related to G2 genotype (P = 0.07 (95% CI = 0.00 , 0.18)). The results of the subgroup analysis showed that in the G1 genotype the highest prevalence was observed in Goats and Buffaloes with P = 1 (95% CI = 0.96 , 1) and P = 1 (95% CI = 0.97 , 1), in the G3 and G6 genotypes the highest prevalence was observed in camels with P = 0.50 (95% CI = 0.31 , 0.69), and P = 0.45 (95% CI = 0.22 , 0.69), respectively. Conclusion. The cystic echinococcosis genotypes vary from region to region or from country to country and also from host to host, and according to the results, it should always be stopped in areas where the prevalence of such genomes suitable for livestock as well as human food sources to prevent infection of livestock and thus human exposure to cystic echinococcosis. [ABSTRACT FROM AUTHOR]

In this paper, a novel single-stage three-port inverter that connects photovoltaic (PV) panel to a single-phase power grid is introduced. In a single-phase grid-connected PV panel, the input power is constant during the line-frequency period, while the output power oscillates at double-line frequency. A series active power decoupling circuit utilizing thin-film capacitors is incorporated to a conventional flyback inverter to handle input and output power differences. Therefore, popularly low-reliable electrolytic capacitors are replaced with small long-lifetime thin film. The proposed inverter can extract the maximum power from PV, deliver a low total harmonic distortion sinusoidal current to the output, and decouple the input and output powers. The proposed power decoupling circuit shares the inverter main switch. Thus, these functions are achieved using just three switches and a simple control scheme which is applicable for both charging and discharging states. Operation principle and control strategy are discussed in detail. Experimental results based on a 100-W prototype inverter verify feasibility and functionality of the proposed inverter. [ABSTRACT FROM PUBLISHER]

Multiterminal converters eliminate using several single-input-single-output converters and simplify their topologies and reduce their cost. In this paper, a new family of multi-input converters based on three switches leg is introduced. Inputs of the proposed converters are similar and they are topologically interchangeable and have boost or buck operation modes. The proposed converter has one output that operates as an inverter. Here, all operating modes of the proposed converters and their effects on each other are investigated, in details. Also, an appropriate switching technique for the converters is given. A detailed comparison between conventional and proposed two-input converters is also presented. A two-input, one-output prototype converter has been implemented to validate the given analyses and to verify the proposed converter's performance. The experimental results are in good agreement with the theoretical and simulated analyses. [ABSTRACT FROM AUTHOR]

Objective: To assess the effect of a blended educational program to promote performing the PST among Iranian women. Design: In a randomized control trial four main variables; knowledge, attitude, self-efficacy, and practice about PST was evaluated using a man–made questionnaire for PST. Setting: Women aged 18–49 living in Andimeshk (Khuzestan, Iran), covered by 16 health centers, participated in study from November 2019 till April 2019. Method: The educational intervention conducted to increasing women's performing the PST. The experimental group received an intervention, whereas the control group received usual care. Participants were tested at four-time points: pre-test (baseline), post-test 1 (immediately after the program's completion) post-test 2 (4 weeks after the program's completion) and post-test 3 (12 weeks after the program completion). Results: A total of 84 women with average aged 32.27 (42 in the experimental group, 42 in the control group) were recruited from 16 health centers in Andimeshk, southern Iran. Significant group differences were found at different times in knowledge, attitude, self-efficacy, and practice about PST. Conclusion: A blended method was effective in sustaining the effects of the educational program in the experimental group. The development of appropriate teaching method on restricted situation such as COVID-19 pandemic to promote participation is suggested. Plain Language Summary: Cervical cancer is the fourth most common cancer among women. The Pap-test is considered the most economical and efficient method for screening cervical cancer and is a simple method without any side effects. Given that awareness with proper methods regarding the initial symptoms, timely diagnosis and treatment are vital for controlling cancer. In this study, we assessed the effect of a blended educational program to promote performing Pap-test among 84 Iranian women. Therefore, a study to assess four main variables; knowledge, attitude, self-efficacy, and practice about PST was designed. We asked women aged 18–49 living in Andimeshk (Khuzestan, Iran) covered by 16 health centers. The educational program to increase women's performance in the PST using online technology regarding participants' convenience, accessibility, and availability of educational content. Women were divided into two groups. One group received an educational program, the second group remained in control and did not receive any education. All women were asked for their knowledge, attitude, self-efficacy and practice of PST three times immediately, 4 and 12 weeks after one-month training. Our assessment showed significant group differences at different times in knowledge, attitude, self-efficacy, and practice about PST. In conclusion, effective online education in sustaining the effects of the educational program in the experimental group happened. Moreover, we experienced an appropriate teaching method for restricted situations such as the COVID-19 pandemic to promote educational participation. [ABSTRACT FROM AUTHOR]

In this paper, a new zero-voltage-switching, high power-factor, bridgeless rectifier is introduced. In this topology, an auxiliary circuit provides soft switching for all of the power semiconductor devices. Thus the switching losses are reduced and the highest efficiency can be achieved. The proposed converter has been analyzed and a design procedure has been introduced. The control circuit for the converter has also been developed. Based on the given approach, a 250 W, 400 Vdc prototype converters has been designed at 100 kHz for universal input voltage (90-264 Vrms) applications. A maximum efficiency of 94.6% and a power factor correction over 0.99 has been achieved. The simulation and experimental results confirm the design procedure and highlight the advantages of the proposed topology. [ABSTRACT FROM AUTHOR]

Resonant switched-capacitor converters (SCCs) are being increasingly used in energy conversion systems due to their low cost, low weight, and high efficiency. The zero-current switching (ZCS) feature of an SCC, which can be achieved at a switching frequency below the resonant frequency, not only results in soft switching and, hence, low switching losses, but also reduces the electromagnetic interference caused by the converter. This paper proposes a cascaded step-down SCC (CSD-SCC) with an arbitrary number of converter stages and an exponential output-to-input voltage ratio. This SCC reduces the number of required converter stages for a low voltage conversion ratio and has a low ripple in the output voltage. A mathematical study is proposed to analyze the operating modes of this generalized CSD-SCC under ZCS operation. This study also enables the calculation of the output voltage, the output voltage ripple, and the efficiency for different switching frequencies and loads. The proposed analysis is validated via several simulation and experimental case studies, including a photovoltaic energy conversion system. The experimental CSD-SCC has two converter stages with an efficiency higher than  $\text{95}\%$. [ABSTRACT FROM AUTHOR]

Objective: There is a likelihood of risky behaviors such as drug abuse, risky sexual behavior, and adaptability issues in young ages. The present study aimed at investigating the prevalence of risky behaviors among students of Dezful University of Medical Sciences in 2014. Methods: This was a descriptive-analytical cross sectional study, with a random sampling approach. Scale of measuring risky behaviors was used to measure the risky behaviors (high speed driving, maim, drug use, and sexual behaviors) and related factors. The mean, standard deviation, Chi-square tests, t tests, and ANOVA were used for data analysis. Results: The study was conducted on 150 (50%) female and 150 (50%) male students. Most of the participants aged 20 to 24 years. A statistically significant difference was obtained between the average scores of risky behaviors among female and male students (p<0.05). The results of the present study revealed that the prevalence of risky behaviors, high speed driving, and drug consumption was different among the students of various study fields (p<0.05). Conclusion: The prevalence of risky behaviors among students of Dezful University was relatively low, and the prevalence of these behaviors in female students was far less than in male students. Risky behaviors were associated with background variables, except for mother's occupation. [ABSTRACT FROM AUTHOR]