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Purpose Insufficient sleep and insomnia are common issues associated with modern lifestyles that often contribute to the development of mental health disorders. 4‐aminopyridine (4‐AP), a voltage‐gated potassium (Kv) channel antagonist, is commonly used in the treatment of multiple sclerosis (MS). It has been shown to improve nerve conduction velocity, strengthen myelin, and increase axonal area after injury. In addition, 4‐AP has been reported to reduce behavioral disorders, including depression. The aim of this study was to investigate the effects of 4‐AP on anxiety‐like behavior in mice subjected to rapid eye movement (REM) sleep deprivation. Methods Fifty male mice were randomly divided into five groups: control, normal saline (NS) (receiving normal saline via gavage), AP‐0.25, AP‐0.5, and AP‐1 (receiving daily doses of 0.25, 0.5, and 1 mg/kg of 4‐AP, respectively by gavage). All groups except the control group underwent SD for five consecutive days. The animals' locomotion and anxiety‐like behavior were assessed using the open field and elevated plus maze tests. After behavioral testing, N‐methyl‐D‐aspartate receptor (NMDA‐R), α‐amino‐3‐hydroxy‐5‐methyl‐4‐isoxazolepropionic acid receptor (AMPA‐R), and tumor necrosis factor (TNF‐α) were measured by western blotting, and also malondialdehyde (MDA) and total antioxidant capacity (TAC) were analyzed by ELISA in the hippocampus. Finding AP‐1 significantly reduced the levels of anxiety‐like behavior compared to the NS group in both tests. In AP‐1, a significant decrease in the levels of NMDA‐R, AMPA‐R, TNF‐α, and MDA was observed. While these levels were increased in the NS group. In addition, AP‐1 showed a higher level of TAC compared to the NS group, indicating an increase in antioxidant levels. Conclusion 4‐AP may be effective in reducing anxiety‐like behavior in sleep‐deprived mice by modifying the levels of NMDA‐R, AMPA‐R, and TNF‐α, while simultaneously reducing oxidative stress induced by sleep deprivation in the hippocampus. 4‐AP may be effective in attenuating anxiety‐like behavior in sleep‐deprived mice by modifying the levels of NMDA‐R and AMPA‐R and TNF‐α and simultaneously reducing oxidative stress in the hippocampus.

It is predicted that the continuously increasing demand for the energy-critical element of lithium will soon exceed its availability, rendering it a geopolitically significant resource. The present work critically reviews recent reports on Li + selective membranes. Particular emphasis has been placed on the basic principles of the materials’ design for the development of membranes with nanochannels and nanopores with Li + selectivity. Fundamental and practical challenges, as well as prospects for the targeted design of Li + ion-selective membranes are also presented, with the goal of inspiring future critical research efforts in this scientifically and strategically important field. Lithium is in increasing demand for energy storage and is abundant in seawater, but its extraction is challenging due to coexistence with similar ions. Here the authors review recent advances in lithium separation strategies, focusing on the development of nanochannel and nanopore based membranes.

A large-scale silicon nanophotonic phased array with more than 4,000 antennas is demonstrated using a state-of-the-art complementary metal-oxide–semiconductor (CMOS) process, enabling arbitrary holograms with tunability, which brings phased arrays to many new technological territories. New dimension to photonic nanoarrays Nanophotonic approaches allow the construction of chip-scale arrays of optical nanoantennas capable of producing radiation patterns in the far field. This could be useful for a range of applications in communications, LADAR (laser detection and ranging) and three-dimensional holography. Until now this technology has been restricted to one-dimensional or small two-dimensional arrays. This paper reports the construction of a large-scale silicon nanophotonic phased array containing 4,096 optical nanoantennas balanced in power and aligned in phase. The array was used to generate a complex radiation pattern—the MIT logo—in the far field. The authors show that this type of nanophotonic phased array can be actively tuned, and in some cases the beam is steerable. Electromagnetic phased arrays at radio frequencies are well known and have enabled applications ranging from communications to radar, broadcasting and astronomy 1 . The ability to generate arbitrary radiation patterns with large-scale phased arrays has long been pursued. Although it is extremely expensive and cumbersome to deploy large-scale radiofrequency phased arrays 2 , optical phased arrays have a unique advantage in that the much shorter optical wavelength holds promise for large-scale integration 3 . However, the short optical wavelength also imposes stringent requirements on fabrication. As a consequence, although optical phased arrays have been studied with various platforms 4 , 5 , 6 , 7 , 8 and recently with chip-scale nanophotonics 9 , 10 , 11 , 12 , all of the demonstrations so far are restricted to one-dimensional or small-scale two-dimensional arrays. Here we report the demonstration of a large-scale two-dimensional nanophotonic phased array (NPA), in which 64 × 64 (4,096) optical nanoantennas are densely integrated on a silicon chip within a footprint of 576 μm × 576 μm with all of the nanoantennas precisely balanced in power and aligned in phase to generate a designed, sophisticated radiation pattern in the far field. We also show that active phase tunability can be realized in the proposed NPA by demonstrating dynamic beam steering and shaping with an 8 × 8 array. This work demonstrates that a robust design, together with state-of-the-art complementary metal-oxide–semiconductor technology, allows large-scale NPAs to be implemented on compact and inexpensive nanophotonic chips. In turn, this enables arbitrary radiation pattern generation using NPAs and therefore extends the functionalities of phased arrays beyond conventional beam focusing and steering, opening up possibilities for large-scale deployment in applications such as communication, laser detection and ranging, three-dimensional holography and biomedical sciences, to name just a few.

Silicon photonics has emerged as the leading candidate for implementing ultralow power wavelength–division–multiplexed communication networks in high-performance computers, yet current components (lasers, modulators, filters and detectors) consume too much power for the high-speed femtojoule-class links that ultimately will be required. Here we demonstrate and characterize the first modulator to achieve simultaneous high-speed (25 Gb s −1 ), low-voltage (0.5  V PP ) and efficient 0.9 fJ per bit error-free operation. This low-energy high-speed operation is enabled by a record electro-optic response, obtained in a vertical p – n junction device that at 250 pm V −1 (30 GHz V −1 ) is up to 10 times larger than prior demonstrations. In addition, this record electro-optic response is used to compensate for thermal drift over a 7.5 °C temperature range with little additional energy consumption (0.24 fJ per bit for a total energy consumption below 1.03 J per bit). The combined results of highly efficient modulation and electro-optic thermal compensation represent a new paradigm in modulator development and a major step towards single-digit femtojoule-class communications. Optical modulators on silicon promise to deliver ultralow power communication networks between or within computer chips. Here, the authors demonstrate a silicon modulator operating with less than one femtojoule energy and are able to compensate for thermal drift over a 7.5 °C temperature range.

Objective Prenatal stress (PS) is a problematic situation resulting in psychological implications such as social anxiety. Ubiquitous extremely low‐frequency electromagnetic fields (ELF‐EMF) have been confirmed as a potential physiological stressor; however, useful neuroregenerative effect of these types of electromagnetic fields has also frequently been reported. The aim of the present study was to survey the interaction of PS and ELF‐EMF on anxiety‐like behavior. Method A total of 24 female rats 40 days of age were distributed into four groups of 6 rats each: control, stress (their mothers were exposed to stress), EMF (their mothers underwent to ELF‐EMF), and EMF/stress (their mothers concurrently underwent to stress and ELF‐EMF). The rats were assayed using elevated plus‐maze and open field tests. Results Expressions of the hippocampus GAP‐43, BDNF, and caspase‐3 (cas‐3) were detected by immunohistochemistry in Cornu Ammonis 1 (CA1) and dentate gyrus (DG) of the hippocampus and prefrontal cortex (PFC). Anxiety‐like behavior increased in all treatment groups. Rats in the EMF/stress group presented more serious anxiety‐like behavior. In all treatment groups, upregulated expression of cas‐3 was seen in PFC, DG, and CA1 and downregulated expression of BDNF and GAP‐43 was seen in PFC and DG and the CA1. Histomorphological study showed vast neurodegenerative changes in the hippocampus and PFC. Conclusion The results showed ,female rats that underwent PS or/and EMF exhibited critical anxiety‐like behavior and this process may be attributed to neurodegeneration in PFC and DG of the hippocampus and possibly decreased synaptic plasticity so‐called areas. The present study showed that PS and ELF‐EMF could have potential hazardous implications in neurogenration in hippocamus and PFC in the pregnancy period and could result in anxiety‐like behavior in offspring. We also found for the first time that omnipresent ELF‐EMF not only induces neurodegeneration effects on hippocamus and PFC but also could exacerbate anxiey like behavior of PS, which may be attributed to hippocampal and PFC neurodegeneration and also neuroplasticity reduction.

Recently, the demand for residence and usage of urban infrastructure has been increased, thereby resulting in the elevation of risk levels of human lives over natural calamities. The occupancy demand has rapidly increased the construction rate, whereas the inadequate design of structures prone to more vulnerability. Buildings constructed before the development of seismic codes have an additional susceptibility to earthquake vibrations. The structural collapse causes an economic loss as well as setbacks for human lives. An application of different theoretical methods to analyze the structural behavior is expensive and time-consuming. Therefore, introducing a rapid vulnerability assessment method to check structural performances is necessary for future developments. The process, as mentioned earlier, is known as Rapid Visual Screening (RVS). This technique has been generated to identify, inventory, and screen structures that are potentially hazardous. Sometimes, poor construction quality does not provide some of the required parameters; in this case, the RVS process turns into a tedious scenario. Hence, to tackle such a situation, multiple-criteria decision-making (MCDM) methods for the seismic vulnerability assessment opens a new gateway. The different parameters required by RVS can be taken in MCDM. MCDM evaluates multiple conflicting criteria in decision making in several fields. This paper has aimed to bridge the gap between RVS and MCDM. Furthermore, to define the correlation between these techniques, implementation of the methodologies from Indian, Turkish, and Federal Emergency Management Agency (FEMA) codes has been done. The effects of seismic vulnerability of structures have been observed and compared.

The hazardous effects of pollutants from conventional fuel vehicles have caused the scientific world to move towards environmentally friendly energy sources. Though we have various renewable energy sources, the perfect one to use as an energy source for vehicles is hydrogen. Like electricity, hydrogen is an energy carrier that has the ability to deliver incredible amounts of energy. Onboard hydrogen storage in vehicles is an important factor that should be considered when designing fuel cell vehicles. In this study, a recent development in hydrogen fuel cell engines is reviewed to scrutinize the feasibility of using hydrogen as a major fuel in transportation systems. A fuel cell is an electrochemical device that can produce electricity by allowing chemical gases and oxidants as reactants. With anodes and electrolytes, the fuel cell splits the cation and the anion in the reactant to produce electricity. Fuel cells use reactants, which are not harmful to the environment and produce water as a product of the chemical reaction. As hydrogen is one of the most efficient energy carriers, the fuel cell can produce direct current (DC) power to run the electric car. By integrating a hydrogen fuel cell with batteries and the control system with strategies, one can produce a sustainable hybrid car.

Determining the risk priorities for the building stock in highly seismic-prone regions and making the final decisions about the buildings is one of the essential precautionary measures that needs to be taken before the earthquake. This study aims to develop an Artificial Neural Network (ANN)-based model to predict risk priorities for reinforced-concrete (RC) buildings that constitute a large part of the existing building stock. For this purpose, the network parameters in the network structure have been optimized by establishing a hybrid structure with the Genetic Algorithm (GA). As a result, the ANN model can make accurate predictions with maximum efficiency. The suggested ANN model is a feedforward back-propagation network model. It aims to predict the risk priorities for 329 RC buildings in the most successful way, for which the performance score was calculated using the Turkey Rapid Evaluation Method (2013). In this paper, a GA-ANN hybrid model was implemented in which the ANN, using the most successful gene revealed by the model, produced successful results in calculating the performance score. In addition, the required input parameters for obtaining more efficient results in solving such a problem and the parameters that need to be used in establishing such an ANN network structure have been optimized. With the help of such a model, the operation process will be eliminated. The created hybrid model was 98% successful in determining the risk priority in RC buildings.

Inducer is an important device which is mounted upstream of the inlet to the main impeller of the centrifugal pump and rotates at the same rotational speed as the impeller. The main purpose of the inducer is to improve the suction performance of the pump, but this improvement is dependent on the geometrical parameters of the inducer. Therefore, it is essential to optimize these parameters. In the present study, the performance of an inducer is optimized by considering the inlet tip blade angle, the outlet tip blade angle, and the ratio of the outlet hub radius to inlet hub radius as design variables and the head coefficient, the hydraulic efficiency, and the required net positive suction head (NPSHR) as objective functions. The inducer performance is simulated using 3-D computational fluid dynamics (CFD) and compared with experimental data, which shows the validity of the used method and assumptions. Then the group method of data handling (GMDH) algorithm is used to model the objective functions with respect to design variables. Using the modified non-dominated sorting genetic algorithm II (NSGA-II) approach, Pareto fronts are then plotted and trade-off optimum points are obtained using the technique for order of preference by similarity to ideal solution (TOPSIS). Using multi-objective optimization, the head coefficient, the hydraulic efficiency, and NPSHR are improved 14.3%, 0.3%, and 30.2%, respectively. Recommended design points unveil significant optimum design principles that can be obtained only by using a multi-objective optimization approach.

There is a disagreement on whether extremely low frequency electromagnetic fields (ELF-EMF) have a beneficial or harmful effect on anxiety-like behavior. Prenatal stress induces frequent disturbances in offspring physiology such as anxiety-like behavior extending to adulthood. This study was designed to evaluate the effects of prenatal stress and ELF-EMF exposure before and during pregnancy on anxiety-like behavior and some anxiety-related pathways in the hippocampus of female rat offspring. A total of 24 female rats 40 days of age were distributed into four groups of 6 rats each: control, Stress (rats whose mothers underwent chronic stress), EMF (rats whose mothers were exposed to electromagnetic fields) and EMF/S (rats whose mothers were simultaneously exposed to chronic stress and ELF-EMF). The rats were given elevated plus-maze and open field tests and then their brains were dissected and their hippocampus were subjected to analysis. ELISA was used to measure 24(S)-hydroxy cholesterol, corticosterone, and serotonin levels. Cryptochrome2, steroidogenic acute regulatory protein, 3B-Hydroxy steroid dehydrogenase, N-methyl-D-aspartate receptor 2(NMDAr2) and phosphorylated N-methyl-D-aspartate receptor 2(PNMDAr2) were assayed by immunoblotting. Anxiety-like behavior increased in all treatment groups at the same time EMF increased anxiety induced by maternal stress in the EMF/S group. The stress group showed decreased serotonin and increased corticosterone levels. ELF-EMF elevated the PNMDAr2/NMDAr2 ratio and 24(S)-hydroxy cholesterol compared to the control group but did not change corticosterone. EMF did not restore changes induced by stress in behavioral and molecular tests. The results of the current study, clarified that ELF-EMF can induce anxiety-like behavior which may be attributed to an increase in the PNMDAr2/NMDAr2 ratio and 24(S)-OHC in the hippocampus, and prenatal stress may contribute to anxiety via a decrease in serotonin and an increase in corticosterone in the hippocampus. We also found that anxiety-like behavior induced by maternal stress exposure, is exacerbated by electromagnetic fields radiation.