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Transformation toward a low-carbon sustainable energy system is getting more recognition in oil-rich developing countries under pressure exerted by their growing environmental challenges and international treaties- including UN SDGs. This calls for concerted efforts for developing renewable energy technologies (RETs). In this regard, the current paper examines the historical development of the solar photovoltaic (PV) niche formation in Iran from 1990 to 2020 in two chronological phases, i.e., technological niches and market niches. We adopt strategic niche management framework and highlight the active role of government support should plays as a key prerequisite required for RET niches development in oil-rich developing countries (ORDCs) where market is heavily in favor of fossil sources of energy. Data was gathered through 19 semi-structured interviews as well as PV-related science and technology development activities. We found that while universities and research institutions played a pivotal role in PV technological niche formation, foreign direct investment (FDI) and local firms were instrumental in PV market niche development. Our findings provide recommendations to direct ORDCs in developing PV, which include proper implementation of feed-in tariff policy, enhanced collaboration among international and local actors, integrated and balanced development of the PV value chain, diversified application of PV in the residential and industrial sectors, and lastly, leveraging FDI and joint-ventures as means of promoting local technological capabilities, industrialization, and market expansion. • Renewable niches formation process entails two distinct technological and market phases. • Government support has explanatory power about how renewable niches form. • Government support is crucial for diffusion of renewable niches in oil-rich countries. • International collaborations and investment facilitate renewable niches formation. [ABSTRACT FROM AUTHOR]

Emerging avian influenza viruses pose a high risk to poultry production, necessitating the need for more broadly protective vaccines. Live attenuated influenza vaccines offer excellent protective efficacies but their use in poultry farms is discouraged due to safety concerns related to emergence of reassortant viruses. Vaccination of chicken embryos inside eggs (in ovo) induces early immunity in young chicks while reduces the safety concerns related to the use of live vaccines on farms. However, in ovo vaccination using influenza viruses severely affects the egg hatchability. We previously engineered a high interferon-inducing live attenuated influenza vaccine candidate with an enhanced protective efficacy in chickens. Here, we asked whether we could further modify this high interferon-inducing vaccine candidate to develop an in ovo -compatible live attenuated influenza vaccine. We first showed that the enhanced interferon responses induced by the vaccine is not enough to attenuate the virus in ovo. To reduce the pathogenicity of the virus for chicken embryos, we replaced the hemagglutinin cleavage site of the H7 vaccine virus (PENPKTR/GL) with that of the H6-subtype viruses (PQIETR/GL) and disrupted the ribosomal frameshifting site responsible for viral polymerase acidic X protein expression. In ovo vaccination of chickens with up to 105 median egg infectious dose of the modified vaccine had minimal effects on hatchability while protecting the chickens against a heterologous challenge virus at two weeks of age. This study demonstrates that targeted genetic mutations can be applied to further attenuate and enhance the safety of live attenuated influenza vaccines to develop future in ovo vaccines for poultry. [ABSTRACT FROM AUTHOR]

Under irradiation, Zr and Zr alloys undergo growth in the absence of applied stress. This phenomenon is thought to be associated with the anisotropy of diffusion of either or both radiation-induced point defects and defect clusters. In this work, molecular dynamic simulations are used to study the anisotropy of diffusion of self-interstitial atom clusters. Both near-equilibrium clusters generated by aggregation of self-interstitial atoms and cascade-induced clusters were considered. The cascade-induced clusters display more anisotropy than their counterparts produced by aggregation. In addition to 1-dimensional diffusing clusters, 2-dimensional diffusing clusters were observed. Using our molecular dynamic simulations, the input parameters for the "self-interstitial atom cluster bias" rate-theory model were estimated. The radiation-induced growth strains predicted using this model are largely consistent with experiments, but are highly sensitive to the choice of interatomic interaction potential. [ABSTRACT FROM AUTHOR]

A new triple-layer, electrospun nanofiber membrane was fabricated in sequential electrospinning steps for enhancing the thermal efficiency of the membrane for desalination of high-salinity solution in a membrane distillation process. The membrane structure is designed to form a Janus structure comprised of two hydrophobic layers made of polyvinylidene fluoride and polystyrene at the top and middle, respectively, and one hydrophilic layer made of polyacrylonitrile at the bottom layer (support). The low thermal conductivity of the polystyrene layer and the Janus structure of the membrane could considerably enhance the flux and thermal performance of the membrane for desalination of hypersaline solution. The experimental results demonstrated that the designed membrane achieved high permeate flux and high energy efficiency compared with single and dual-layer membranes when used for treatment of high salinity solution. The results further showed that increasing feedwater salinity dropped the permeate flux of the single-layer membrane by over 50 % and reached 10 L/m2h, while for the triple-layer membrane, it just dropped 20 % for the feed salinity of 200 g/l. Moreover, the triple-layer membrane showed 20 % higher energy efficiency at the same operation conditions. Furthermore, a simulation model was developed and validated via the experimental results to understand the effect of various parameters. [Display omitted] • Triple-layer nanofiber membrane was fabricated in sequential electrospinning step. • Energy efficiency of the membranes for DCMD was improved. • Hydrophilic layer worked as a support layer/amplifier of water vapor transfer across membrane. • Triple-layer membrane demonstrated high permeate flux and energy efficiency. [ABSTRACT FROM AUTHOR]

• TARV-infected SPF turkeys recapitulate the disease observed in commercial turkeys. • Reoviral arthritis features in SPF turkeys include: hock joint swelling, tenosynovitis, tibiotarsal cartilage erosion, and gait defects. • SPF turkey reoviral arthritis model will be instrumental in evaluation of TARV pathogenesis and reoviral vaccine efficacy. Turkey arthritis reovirus (TARV) infections have been recognized since 2011 to cause disease and significant economic losses to the U.S. turkey industry. Reoviral arthritis has been reproduced in commercial-origin turkeys. However, determination of pathogenesis or vaccine efficacy in these turkeys can be complicated by enteric reovirus strains and other pathogens that ubiquitously exist at subclinical levels among commercial turkey flocks. In this study, turkeys from a specific-pathogen-free (SPF) flock were evaluated for use as a turkey reoviral arthritis model. One-day-old or 1-week-old poults were orally inoculated with TARV (O'Neil strain) and monitored for disease onset and progression. A gut isolate of turkey reovirus (MN1 strain) was also tested for comparison. Disease was observed only in TARV-infected birds. Features of reoviral arthritis in SPF turkeys included swelling of hock joints, tenosynovitis, distal tibiotarsal cartilage erosion, and gait defects (lameness). Moreover, TARV infection resulted in a significant depression of body weights during the early times post-infection. Age-dependent susceptibility to TARV infection was unclear. TARV was transmitted to all sentinel birds, which manifested high levels of tenosynovitis and tibiotarsal cartilage erosion. Simulation of stressful conditions by dexamethasone treatment did not affect the viral load or exacerbate the disease. Collectively, the clinical and pathological features of reoviral arthritis in the SPF turkey model generally resembled those induced in commercial turkeys under field and/or experimental conditions. The SPF turkey reoviral arthritis model will be instrumental in evaluation of TARV pathogenesis and reoviral vaccine efficacy. [ABSTRACT FROM AUTHOR]

Abstract Avian influenza in poultry continues to be a great concern worldwide, and the currently licensed inactivated influenza vaccines are not effective against the novel strains of influenza virus that continue to emerge in the field. This warrants the development of more broadly protective influenza vaccines or vaccination regimens. Live attenuated influenza vaccines (LAIVs) and subunit vaccines derived from viral peptides, such as the highly conserved ectodomain of influenza virus matrix protein 2 (M2e), can offer a more broadly reactive immune response. In chickens, we previously showed that a chimeric norovirus P particle containing M2e (M2eP) could provide partial but broad immunity, when administered as a standalone vaccine, and also enhanced the protective efficacy of inactivated vaccine when used in a combination regimen. We also demonstrated that a naturally-selected NS1-truncated H7N3 LAIV (pc4-LAIV) was highly efficacious against antigenically distant heterologous H7N2 low pathogenicity avian influenza virus challenge, especially when used as the priming vaccine in a prime-boost vaccination regimen. In this study, we investigated the cross-subtype protective efficacy of pc4-LAIV in conjunction with M2eP using single vaccination, combined treatment, and prime-boost approaches. Chickens vaccinated with pc4-LAIV showed significant reduction of tracheal shedding of a low pathogenicity H5N2 challenge virus. This cross-subtype protective efficacy was further enhanced, during the initial stages of challenge virus replication, in chickens that received a vaccination regimen consisting of priming with pc4-LAIV at 1 day of age and boosting with M2eP. Further, H5N2-specific serum IgG and pc4-LAIV-specific hemagglutination-inhibition antibody titers were enhanced in LAIV-primed and M2eP boost-vaccinated chickens. Taken together, our data point to the need of further investigation into the benefits of combined and prime-boost vaccination schemes utilizing LAIV and epitope-based vaccines, to develop more broadly protective vaccination regimens. [ABSTRACT FROM AUTHOR]

Transportation sector is responsible for a considerable share of total energy consumption and greenhouse gas (GHG) emissions. Widespread electric vehicles (EVs) adoption is instrumental in achieving sustainability. This paper aims to elaborate the future scenarios of EVs development and diffusion in Iran by 2040. By adjusting the conventional intuitive logics school, to more efficiently engage public and private stakeholders and to enhace policy informing of the secenario planning results, we identified nine driving forces that shape the future of EVs. Our findings indicate that government policies and the maturity of EV technology development are the two axis of the scenario matrix and the most critical uncertainties. We outline four possible future scenarios for EVs development and diffusion. "EVs persistently struggle under the rule of non-EVs" is the probable scenario, while "EVs rule the streets" is the preferable scenario. This paper also discusses the neglected influence of oil-rich developing countries' context and efficiency of policies on the probable and preferable future scenarios of EVs in Iran. Our proposed scenarios shed light on the uncertainties of EVs development and diffusion, which policy-makers and firms in Iran and other developing countries need to consider in their future policies and strategies. Implications of this research can be helpful if transitioning from a fossil-based transportation system to a sustainable one is on the agenda of oil-rich countries beyond the prevalent political rhetorics toward EVs. • Proposing probable and preferable future scenarios of EVs in Iran 2040. • Identifying major driving forces shaping the future of EVs. • Government policies and regulations have a dichotomous effect on EVs development. • Context of oil-rich developing countries is a determining factor in EVs diffusion. • Adjusting conventional intuitive logics to make it more pragmatic. [ABSTRACT FROM AUTHOR]

• Proposal has distance protection scheme for the lines connected to the PV plants. • The proposed scheme is independent of PV plant parameters and fault resistance. • In this method the exact fault location is also calculated. The output power of the inverter-interfaced photovoltaic (PV) plant has the continuous variations due to the properties of PV modules and environmental conditions. These variations fundamentally affect the performance of the conventional distance protection during nonmetallic faults. This paper proposes a positive sequence network-based distance protection scheme for the transmission lines connected to the PV plants. Different from the adaptive mho and quadrilateral characteristics, the proposed scheme is independent of PV plant parameters and fault resistance. In this method, the Thevenin equivalent parameters of the grid seen from the PV plant are calculated. Thevenin equivalent parameters are calculated using prefault current and voltage data at the local terminal, without additional costs related to the requirements of the communication channel. The obtained parameters are used in the fault resistance compensation. Furthermore, by eliminating the fault resistance effect on the relay impedance, the exact fault location is also calculated. Since the fault line impedance formula is derived only from the positive sequence network, the proposed method is applicable to different grid codes. The efficiency of the proposed scheme is evaluated on the Western System Coordinating Council (WSCC) 9-bus and IEEE 30-bus test systems. The obtained simulation results verify the validity of the proposed scheme under various fault and PV plant conditions. [ABSTRACT FROM AUTHOR]

The presence of flexible ac transmission system (FACTS) controllers in transmission lines causes mal-operation of distance relays. The series-shunt FACTS devices have larger influence on the performance of the relays compare to the other FACTS controllers. Furthermore, high-resistance fault is another factor that relay become under-reach and cannot correctly identify the fault. In this paper, a method is provided based on synchrophasors to eliminate the effects of unified power-flow controller (UPFC) and fault resistance on the distance relay. In the presented method, the data of voltage and current signals of buses will be sent to system protection center (SPC). In SPC, an algorithm is provided based on active power calculation in buses which is able to eliminate the effects of both mentioned factors. The main advantage of the proposed method, in addition to the simplicity of the algorithm, is the ability to operate in all types of faults and in high-resistance faults. Furthermore, a technique is presented in this paper to calculate UPFC data. A comparison has been performed between this technique and another method where UPFC data is directly transmitted to SPC by communication channel. In modeling of UPFC, detail model is used based on 48-pulses voltage source converters. [ABSTRACT FROM AUTHOR]

Ni(x)-Al 2 O 3 (x = 5, 7.5, 10, 12.5, 15, 17.5, and 20 wt%) catalysts were fabricated by the mechanochemical way, and the samples were used in acetic acid steam reforming. The results showed that all prepared samples have excellent features with a high BET area in the range of 185–215 m2 g−1. Based on the founding results, the reducibility degree of the studied samples was enhanced by raising the nickel content to 17.5 wt%. The activity results revealed that the catalyst with 17.5 wt% Ni showed the best performance, and the acetic acid conversion and hydrogen yield reached 93% and 35% at 450 °C over this sample, respectively. Also, the agglomeration of particles at higher calcination temperatures led to the decrease in acetic acid conversion by increasing the T calcination from 700 to 900 °C. Furthermore, the results demonstrated that the catalytic activity improved by a decrease in GHSV value from 24000 to 12000 ml h−1.g−1 cat and an increase in the S/C molar ratio from 1:1 to 5:1. The influence of reduction temperature on the catalytic performance was also studied over the selected catalysts, and the results indicated that the sample under reduction temperature of 700 °C displayed the highest efficiency in the acetic acid steam reforming, which was related to the existence of more active sites and more acetic acid adsorption on the catalyst surface. [Display omitted] • Ni-Al 2 O 3 catalysts are prepared by the solid-state synthesis method. • The performance of the samples is evaluated in AcOH steam reforming. • The calcined catalysts show excellent physicochemical properties. • 17.5%Ni-Al 2 O 3 catalyst possesses the best efficiency in this process. • The influence of calcination temperature and operating parameters are studied on the catalyst efficiency. [ABSTRACT FROM AUTHOR]

Distance relays are often used in the protection of the transmission lines connected to the wind farms. The distance relay using the transmission line impedance measurement identifies the type and location of the fault. However any other factors that cause the failure of the measured impedance, makes the relay detect the fault in incorrect location or do not detect the fault at all. One of these factors is the fault resistance which directly increases the measured impedance by the relay. One of the methods to eliminate relay under-reach effect is using of the trip boundaries. Trip boundaries are changing with wind variation and following with output power of the wind farms. Therefore, trip boundaries should continuously change proportional by the wind speed. In this paper, a method is provided based on the combination of distance and differential protection. In this method, using active power calculation in both ends of the transmission line, fault resistance is calculated and its effects are directly deducted from the calculated impedance by the relay. Therefore, variable trip boundaries are not needed anymore. Also in this method, unlike the technique that the trip boundaries are used, the exact location of fault and its distance from the relay also is calculated. Detailed model of a doubly-fed induction generator (DFIG) driven by a wind turbine is used in the modelling. Results of studies show that the presented method eliminates properly the mal-operation of relays under all different fault resistance conditions. [ABSTRACT FROM AUTHOR]

In this study, a comprehensive model was developed using Computational Fluid Dynamics (CFD), and the behaviour of a direct contact membrane distillation (DCMD) system was investigated at hypersaline feedwater conditions. The effects of various operating parameters including feed and permeate velocities, temperatures and salinities, as well as different membrane characteristics like thickness, porosity, and thermal conductivity were studied. The developed simulation model was also validated using experimental data. The results showed that the membrane conductivity and thickness had a significant impact on the DCMD performance, and the optimum operational condition was necessary to be determined. The results showed that increasing the feedwater salinity from 50 to 200 g/l decreased the membrane flux by up to 33%, while a four times decrease in thermal conductivity of the membrane could lead to an increase in the membrane flux from 11.2 to 32.4 l/m2·h (LMH). In addition, the optimal membrane thickness was found to increase with salinity, reaching >120 μm for treatment of 22 wt% NaCl feedwater solution. However, the flux declined from >32 LMH to <13 LMH upon the increase in feedwater salinity (up to 22 wt% NaCl solution). It is also shown that a thinner membrane performed better for desalination of low salinity feedwater, while the thicker one produces higher separation performance and thermal efficiency for hypersaline brine desalination. [Display omitted] • CFD Simulation of MD process for desalination of high salinity feedwater was performed. • A comprehensive simulation of mass, heat, and momentum transfer was carried out. • The optimum physical properties and operational parameters were obtained. • The effect of thermal conductivity on the performance of the system was investigated. • The optimum thickness of membrane in different operating conditions was obtained. [ABSTRACT FROM AUTHOR]

Evaluating the current situation of ecotourism in Kaji Namakzar Wetland in South Khorasan Province, Iran and offering strategies for its sustainable development are the main objectives of this study. To this end, different decision making tools were used including questionnaires and interviews with experts, local residents and visitors of the wetland. Strengths, weaknesses, opportunities and threats (SWOT) and quantitative strategic planning matrix (QSPM) analysis techniques were conducted to identify the required management strategies. Results showed that the existing ecotourism activities within the wetland are not in line with the sustainability requirements. Although the result of the present study showed that KNW has an unsustainable situation with regard to its current management strategies, if authorities take its great opportunities and strengths more into consideration, it can have positive effects on developing sustainable strategies to increase ecotourism activities in the region and to reduce the adverse effects on the environment. [ABSTRACT FROM AUTHOR]

Abstract: In this paper the impact of Static Synchronous Series Compensator (SSSC) on the impedance calculated by distance relay is investigated. Analytical results are presented and verified by detailed simulations. Six different phase to phase and phase to ground measuring units of the distance relay are simulated to resemble the behavior of the relay. It is shown in this paper that zero sequence of the injected voltage by 48 pulse SSSC converter has the most impact on the apparent impedance seen by the phase to ground fault measuring unit and cause under reaching of distance relay. It can be concluded from the results that SSSC located in the middle of the transmission line cause to divide trip characteristics of distance relay into two separate parts. It is also shown that the over-reaching operation of distance relay might happen in some cases in the presence of SSSC. All the detailed simulations are carried out in MATLAB/Simulink environment. [Copyright &y& Elsevier]

Abstract: In this paper a novel supplementary subsynchronous damping controller (SSDC) is proposed for the STATic synchronous COMpensator (STATCOM) which is capable of damping out subsynchronous oscillations in power system with series compensated transmission lines. An auxiliary subsynchronous damping controller (SSDC) for a STATCOM using the generator rotor speed deviation signal as the stabilizing signal has been designed to damp subsynchronous oscillations. Eigenvalue analysis and transient simulations of detailed nonlinear system are considered to investigate the performance of the controller. Robustness of the controller has been analyzed by facing the system with disturbances leading to significant changes in generator operating point. This paper deals with a cascaded multilevel converter model, which is a 48-pulse (three levels) source converter. The IEEE Second Benchmark (SBM) model is considered for the analysis and the complete digital simulation of the STATCOM within the power system is performed in the MATLAB/Simulink environment. [Copyright &y& Elsevier]

Abstract: The impact of Static Var Compensator (SVC) on the apparent impedance seen by the transmission line distance relay is investigated in this paper. Analytical results are presented and verified by detailed simulations. It is shown that the connection type of the windings of the shunt coupling transformer of the SVC has a remarkable effect on the apparent impedance seen by the distance relay. Six different phase to phase and phase to ground measuring units of the distance relay are simulated to resemble the behavior of the relay. The impact of SVC is more pronounced on the apparent impedance seen by the phase to ground fault measuring units than the others as is shown by the results. Simulation results include different power system operating conditions, SVC control system settings and different fault-type scenarios. The impact of SVC on the relay tripping boundaries is also clearly demonstrated. Detailed and sophisticated models are used for simulating distance protective relay in a digital simulation environment. [Copyright &y& Elsevier]

• A pilot scheme to enhance the fault location for TCSC compensated line is proposed. • In this method only the current data at remote-end should be sent to the local-end. • The proposed algorithm is independent of fault resistance, and TCSC parameters. This paper introduces a communication-aided scheme to enhance the fault detection, and fault location calculation for a thyristor-controlled series capacitor (TCSC) compensated transmission lines. In the proposed method only the current data at the remote-end should be synchronously sent to the local-end. Since the remote-end voltage data do not use in local-end, compared with the conventional pilot impedance-based protection schemes, the proposed method significantly reduces the requirement of data transmission bandwidth. The proposed algorithm is independent of fault resistance, power flow direction, and pre-fault condition. In the proposed method the TCSC parameters are not utilized in the derived fault location formula and as a result, the performance of the proposed method is not impacted due to variations in TCSC parameters. Several major factors are taken to investigate the accuracy of the proposed method, including measurement errors and power swing conditions. The simulation results prove the high accuracy and acceleration of the proposed scheme during all fault cases. [ABSTRACT FROM AUTHOR]

• This method is only based on the current data in relay location. • The proposed method is completely analytical. • A negative-sequence based approach used to fault location estimation. This paper introduces an accurate fault location algorithm for double-circuit transmission lines compensated by Static Var Compensator (SVC). The proposed algorithm is based on the negative-sequence circuit of the transmission system and it depends only on the current data available from one end of the line. Since only magnitudes of current signals are required, there is no need for data synchronization. The proposed technique uses the COMTRADE fault files available from digital distance relays and it can effectively locate the all types of unbalanced faults, regardless the high fault resistance, effect of mutual coupling and SVC current injection information. As one formula can be used for all types of fault, classification of fault types and phase selection are not required. The shunt capacitances of the line are considered by utilizing the distributed parameters model of the transmission lines. The proposed algorithm is rigorously investigated for various fault scenarios in SVC compensated transmission system. The simulation cases in the MATLAB environment verifies that the proposed scheme has excellent performance. Test results are compared with a conventional fault location technique to illustrate the accuracy of the proposed algorithm. [ABSTRACT FROM AUTHOR]

Development of a broadly reactive influenza vaccine that can provide protection against emerging type A influenza viruses is a big challenge. We previously demonstrated that a vaccine displaying the extracellular domain of the matrix protein 2 (M2e) on the surface loops of norovirus P-particle (M2eP) can partially protect chickens against several subtypes of avian influenza viruses. In the current study, a chimeric vaccine containing a conserved peptide from the subunit 2 of hemagglutinin (HA) glycoprotein (HA2) and Arabidopsis thaliana cyanase protein (AtCYN) (HA2-AtCYN vaccine) was evaluated in 2-weeks-old chickens. Depending on the route of administration, the HA2-AtCYN vaccine was shown to induce various levels of HA2-specific IgA in tears as well as serum IgG, which were associated with partial protection of chickens against tracheal shedding of a low pathogenicity H5N2 challenge virus. Furthermore, intranasal administration with a combination of HA2-AtCYN and M2eP vaccines resulted in enhanced protection compared to each vaccine alone. Simultaneous intranasal administration of the vaccines did not interfere with secretory IgA induction by each vaccine. Additionally, significantly higher M2eP-specific proliferative responses were observed in peripheral blood mononuclear cells of all M2eP-vaccinated groups when compared with the mock-vaccinated group. Although tripling the number of M2e copies did not enhance the protective efficacy of the chimeric vaccine, it significantly reduced immunodominance of P-particle epitopes without affecting the robustness of M2e-specific immune responses. Taken together, our data suggests that mucosal immunization of chickens with combinations of mechanistically different cross-subtype-conserved vaccines has the potential to enhance the protective efficacy against influenza virus challenge. [ABSTRACT FROM AUTHOR]