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Despite tremendous efforts toward vaccination, influenza remains an ongoing global threat. The induction of strain-specific neutralizing antibody responses is a common phenomenon during vaccination with the current inactivated influenza vaccines, so the protective effect of these vaccines is mostly strain-specific. There is an essential need for the development of next-generation vaccines, with a broad range of immunogenicity against antigenically drifted or shifted influenza viruses. Here, we evaluate the potential of whole inactivated vaccines, based on chemical and physical methods, as well as new approaches to generate cross-protective immune responses. We also consider the mechanisms by... 

This paper presents a double input-double output bilateral low-pass equivalent amplifier behavioral model that takes into account input source and output load termination mismatches. The model is intended for the system-level simulation of amplifier chains subjected to wideband modulated signals, since it can predict the device's input and output scattered waves and their memory effects, in a wide range of voltage standing wave ratios (VSWR). In addition, the model extraction methodology, and its associated laboratory test bench are discussed, noting the limitations of conventional setups for behavioral model extraction and validation. The model is validated comparing the predicted and... 

Insider threat is a significant security risk for organizations and hard to detect. Most introduced detection methods need contextual data entries about users, or preprocessed user activity logs to detect insider threats which it is costly and time-consuming. In this paper, we introduce a behavior analysis method that learns its context and detects multiple types of insider threats from raw logs and network traffic in real-time. This method, named XABA, learns user roles and exclusive behaviors, through analyzing raw logs related to each network session of the user. Then it checks for some abnormal patterns, and if so, triggers the appropriate alert. XABA is implemented on the big-stream... 

MXenes are a prominent group within 2D materials with extensive utilization in various electrochemical applications due to their notable specific capacitance, swift ion intercalation kinetics, and favorable hydrophilicity. Despite this, they suffer from low oxidation resistance and ease of layer restacking. Herein, an effective approach to overcome this inherent weakness of MXenes was employed by embedding MoS2 nanopetals as pillars into the backbone of Ti3C2Tx MXene by a one-step hydrothermal technique. It not only alleviates the restacking problem of Ti3C2Tx but also shorten the diffusion path of sodium ions. Meanwhile, ammonium bicarbonate as a guest ion agent was utilized to achieve the... 

This paper introduces an analytical approach to obtain fundamental and harmonic load-pull contours using X-parameters. This method is proposed to obtain the optimum load impedance at different harmonics. This approach has been applied on a two port X-parameter model and its results are independently verified by ADS simulation  

This work discusses several extraction procedures for the recently proposed dual input-dual output (DIDO) low pass equivalent behavioral model according to their required excitation signals. These methods are based on passive load pulling and uncontrolled open loop active load pulling but with different type of excitation waveforms. It also addresses the hardware and signal conditioning of the proposed extraction procedures in detail. The performance of the discussed methods are compared based on the datasets extracted from simulation results in ADS. The results show that the use of the active load-pulling can enhance modeling performance  

Developing new cathode materials for intermediate-temperature solid oxide fuel cells (IT-SOFCs) is still challenging. In this study, co-doped Sr3Fe2O7-δ Ruddlesden-Popper (R-P) (Sr3-xPrxFe1.8Co0.2O7-δ x = (0–0.3)) cathode is synthesized by the polymer complex technique as a cathode for IT-SOFCs. The synthesized powders show a desired tetragonal structure of Sr3-xPrxFe1.8Co0.2O7-δ with an I4/mmm space group. The effect of Pr and Co on the physical, thermal, electrical, and electrochemical properties of the cathodes is investigated. The results reveal that Pr/Co co-doping improves electrochemical properties while increasing the electrical resistivity and average thermal expansion coefficients... 

Nowadays, the growing global population and increased industrialization have exacerbated water pollution, posing a significant environmental threat. To tackle this issue, there is an urgent need for effective catalysts to remove pollutants. This study developed a novel N-doped g-C3N4/Nd-doped ZnO (NZ) heterostructure using a green approach by incorporating pomegranate peel waste as a stabilizing and capping agent. Characterization techniques confirmed successful NZ nanohybrid preparation. The synthesized NZ displayed high photocatalytic activity in degrading methylene blue (MB) and tetracycline (TC) pollutants found in wastewater, achieving degradation efficiencies of 95.3 % and 98.3 %,... 

A nonlinear seismic soil-pile-structure interaction (SSPSI) analysis of fixed offshore platforms constructed on pile foundations including both vertical and battered piles is presented. The analysis is carried out in time domain and the effects of soil nonlinearity, discontinuity at pile soil interfaces, energy dissipation through soil radiation damping, formation of soil layers on bed rock, structural material nonlinearity and geometrical nonlinearity are considered. A combination of FEM approach and BNWF approach is used in modeling pile (substructure), platform structure (superstructure) and soil media. Gapping in clay is modeled by a special connector configuration. To find out the... 

Development of reliable and accurate models to estimate carbon dioxide–brine interfacial tension (IFT) is necessary, since its experimental measurement is time-consuming and requires expensive experimental apparatus as well as complicated interpretation procedure. In the current study, feed forward artificial neural network is used for estimation of CO2–brine IFT based on data from published literature which consists of a number of carbon dioxide–brine interfacial tension data covering broad ranges of temperature, total salinity, mole fractions of impure components and pressure. Trial-and-error method is utilized to optimize the artificial neural network topology in order to enhance its... 

In the present study, we performed hydrothermal method as a simple and efficient route for the synthesis of rutile TiO 2 nanostructures in various concentrations of lithium hydroxide solutions. TiO 2 nanopowders with average sizes of 15 and 23 nm were prepared using 4 M and 7 M LiOH solutions. X-ray diffraction analysis (XRD), transmission electron microscope (FEG-STEM), scanning electron microscopy (SEM), and Brunauer-Emmet-Teller (BET) analyses were used in order to characterize the obtained products and comparison of the morphology of the powders obtained in different concentrations of LiOH solvent. It was shown that alkali solution concentration has affected the crystallinity,... 

Through a fast, simple, low cost, surfactant-free and convenient microwave-assisted route, narcis-like ZnO nanostructures (10-15 nm size) with flower diameters in the range of 1-2.5 μm were synthesized. X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared (FTIR) spectroscopy and room temperature photoluminescence (PL) measurements were used to characterize the produced ZnO nanostructures. The principle raw materials - ammonium hydroxide (NH4OH) and zinc acetate dihydrate [Zn(CH3COO)2·2H2O] - were both inexpensive. The method was fast, simple and surfactant-free capable of producing larger quantities of zinc oxide... 

Galvanostatic method was used to electrodeposit Fe nanostructures on platinum electrodes as catalysts. Scanning electron microscopy (SEM) revealed flower-like Fe deposits with high surface area. Carbon nanotubes were grown on flower-like Fe nanostructures by chemical vapor deposition. The structure of the synthesized carbon nanotubes was investigated by scanning electron microscopy, transmission electron microscopy, Raman spectroscopy and X-ray diffraction. According to X-ray diffraction patterns, Fe was the only detected constituent of the deposited coating. The carbon nanotubes had small wall-thickness and wide hollow core  

It is widely supposed that methodological naturalism, understood as a thesis about the methodology of science, is metaphysically neutral, and that this in turn guarantees the value-neutrality of science. In this paper we argue that methodological naturalism is underpinned by certain ontological and epistemological assumptions including evidentialism and the causal closure of the physical, adoption of which necessitates commitment to metaphysical naturalism. © 2019, Springer Nature B.V