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• The improved VMD and DWT are combined to denoise and reconstruct the signal under strong noise without a reference. • The selection of wavelet function and transform level in DWT is optimized by Shannon entropy to denoise the signal without a reference. • The RAPID and the CNN are used to achieve spatial localization and visualization of the composite delamination. In this paper, a damage spatial imaging approach based on novel signal extraction is suggested to reconstruct the Lamb wave response signal under strong noise and realize the spatial localization of damage. First, the Variable Mode Decomposition (VMD) parameters are optimized by the improved Grey Wolf optimization method (IGWO) to decompose the response signal. To rebuild the response signal, the correlation coefficient is used to choose the optimal modal component and the residual. To give the best wavelet function and transform level for adaptive denoising of the reconstructed signal without a reference signal, an enhanced Discrete Wavelet Transform (DWT) based on Shannon entropy is proposed. To achieve damage localization imaging, a damage spatial localization model is built utilizing a reconstruction algorithm for probabilistic inspection of damage (RAPID) approach and a convolutional neural network (CNN). The suggested method may successfully increase the signal-to-noise ratio (SNR) of the reconstructed response signal and lower the error of spatial localization under strong noise through experiments. The spatial localization of composite damage using Lamb wave under strong noise is expanded in this paper. [ABSTRACT FROM AUTHOR]

Magnetic lenses can effectively reduce the fiber diameter and whipping-circle width to control the random behavior of electrospinning. Although the axisymmetric magnetic lens for electrostatic spinning have several potential applications, the effect of its pole-piece structure on the electrostatic spinning process has not been adequately discussed. In this study, we explored the influence of changing the pole piece structure of the magnetic lens on the electrospinning process using experimental and numerical simulation methods. The results showed that for a 12 wt% polyacrylonitrile (PAN) solution, when the applied voltage was 15 kV, the feed rate was 1 mL/h, and current of the magnetic lens was 1 A, the gap width of the magnetic lens had a notable effect on the fiber deposition efficiency of the electrostatic spinning range of the magnetic lens. Appropriately reducing the gap width in the range of 1–10 mm can effectively reduce the deposition range of the fibers and improve fiber film thickness. Furthermore, when the angle of α is 45°, it exerts the most significant effect on the electrostatic spinning spray range and deposition efficiency, and the fiber film thickness and average fiber diameter attain their highest values. When the angle of α increases or decreases from 45°, the fiber film thickness and fiber diameter both show a decreasing trend. A change in the magnetic lens structure can effectively change the ejection range and fiber diameter during electrostatic spinning, which shows great potential in the field of nanofiber production. [Display omitted] • Changing the magnetic lens structure can control the ejection range and fiber diameter during electrostatic spinning. • Study investigates the impact of magnetic lens pole-piece structure on electrospinning using experiments and simulations. • Optimal gap width (1–10 mm) enhances fiber deposition efficiency and film thickness. • Angle α of 45° maximizes electrostatic spinning range, deposition efficiency, fiber film thickness, and diameter. [ABSTRACT FROM AUTHOR]

The homebuilt traditional electrostatic spinning apparatus was equipped with a silicone rubber heating plate and a magnetic lens to produce polyacrylonitrile (PAN) nanofiber films. The PAN nanofibers used in this experiment were examined using a scanning electron microscope (FE-SEM) as well as other characterization tools to determine their morphology, diameter, crystallinity, thickness, and mechanical characteristics. The experimental results showed that the combined effect of two parameters, the temperature of the receiver plate and the magnetic field generated by the magnetic lens let to the production of fibers with a smaller diameter (308 nm). The magnetic field generated by the magnetic lens increased the thickness of the nanofiber membrane, whereas the temperature decreased the diameter of the nanofibers. The combined effect of the temperature and magnetic fields increased the thickness of the nanofiber membrane. The combined effect of the aforementioned parameters led to a nanofiber crystallinity of 70.72%, which was higher than the average crystallinity generated by the individual impact of the said parameters. The mechanical characteristics also improved significantly with an increase in receiver plate temperature. In conclusion, the combined effect of the temperature of the receiver plate and the magnetic field generated by the magnetic lens improved the performance of the PAN nanofibers and was more significant than their independent impact. A foundation for the preparation of high-performance filtration membranes was laid and the results paved the way for industrializing the process. [Display omitted] [ABSTRACT FROM AUTHOR]

The homebuilt traditional electrostatic spinning apparatus was equipped with a silicone rubber heating plate and a magnetic lens to produce polyacrylonitrile (PAN) nanofiber films. The PAN nanofibers used in this experiment were examined using a scanning electron microscope (FE-SEM) as well as other characterization tools to determine their morphology, diameter, crystallinity, thickness, and mechanical characteristics. The experimental results showed that the combined effect of two parameters, the temperature of the receiver plate and the magnetic field generated by the magnetic lens let to the production of fibers with a smaller diameter (308 nm). The magnetic field generated by the magnetic lens increased the thickness of the nanofiber membrane, whereas the temperature decreased the diameter of the nanofibers. The combined effect of the temperature and magnetic fields increased the thickness of the nanofiber membrane. The combined effect of the aforementioned parameters led to a nanofiber crystallinity of 70.72%, which was higher than the average crystallinity generated by the individual impact of the said parameters. The mechanical characteristics also improved significantly with an increase in receiver plate temperature. In conclusion, the combined effect of the temperature of the receiver plate and the magnetic field generated by the magnetic lens improved the performance of the PAN nanofibers and was more significant than their independent impact. A foundation for the preparation of high-performance filtration membranes was laid and the results paved the way for industrializing the process. [Display omitted] [ABSTRACT FROM AUTHOR]

Superior colliculus (SC) is the target of retinal neurons, allowing them to form connections. Cultured stem cells/progenitors can potentially be used as donor tissue to reconstruct degenerated retina including perhaps replacing lost ganglion cells in glaucoma. In which case, it will be essential for these cells to integrate with the central nervous system targets. Here, we have investigated if the mid -brain region containing superior colliculus (SC) provides a permissive environment for the survival and differentiation of neural progenitors, including retinal progenitor cells propagated in cultures. Neural (NPCs) and retinal progenitor cells (RPCs) from green fluorescent protein (GFP) transgenic mice were cultured. Passage two through four neural and retinal progenitor cells were subsequently cocultured with the SC organotypic slices and maintained in culture for 17 and eight days respectively. Differentiation of the neurons was studied by immunocytochemistry for retinotypic neuronal markers. Retinal progenitor cells cocultured with SC slices were able to differentiate into various neuronal morphologies. Some cocultured progenitor cells differentiated into neurons as suggested by class III β tubulin immunoreactivity. In addition, specific retinotypic neuronal differentiation of RPC was detected by immunoreactivity for calbindin and PKC. SC provides a permissive environment that supports survival and differentiation of the progenitor cells. [ABSTRACT FROM AUTHOR]

Abstract: Neural progenitor cells (NPCs) have drawn attention because they offer possible treatment for neurodegenerative disorders in the form of regenerative therapy or transplantation. NPCs adapt and change in response to the cues in the pathological environment. We assessed the effect of pre-exposure to non-cytotoxic levels of oxidative stress, a common pathogenic factor in a number of neurological disorders, on the cell viability and neurosphere morphology of NPCs derived from the periventricular zone of mice brain. Neural progenitor cell viability and neurosphere morphology (neurosphere number, size and chain migration) were assessed in response to cytotoxic levels of oxidative stress in the presence or absence of preconditioning with non-cytotoxic doses of hydrogen peroxide (H2O2). Preconditioning with non-cytotoxic levels of H2O2 provided significant protection against subsequent exposure to lethal doses of H2O2. Preconditioning also modulated alteration in the neurosphere morphology in response to oxidative stress. Oxidative stress increased chain migration and neurosphere size while decreasing neurosphere numbers, specially in the cultures that were preconditioned with higher doses of H2O2. Non-cytotoxic exposure to oxidative stress can evoke endogenous cytoprotection in NPCs. Redox signaling plays a role in other cellular functions of NPCs, namely the chain migration of NPCs from neurospheres, perhaps as a result of its effect on cell differentiation. [Copyright &y& Elsevier]

The static and dynamic mechanical performances of notched and un-notched 3D braided composites were studied. The effect of longitudinal laid-in yarn was investigated in comparison with low braiding angle composites. The specimens were fatigue tested for up to millions of cycles, and the residual strength of the samples that survived millions of cycles was tested. The cross-section of the 3D braided specimens was observed after fatigue loading. It was found that the static and fatigue properties of low angle 3D braided behaved better than longitudinally reinforced 3D braided composites. For failure behavior, pure braids contain damage better and show less damage area than the braids with longitudinal yarns under fatigue loading. More cracks occurred in the 3D braided specimen with axial yarn cross-section along the longitudinal and transverse direction. [ABSTRACT FROM AUTHOR]

This paper provides a new method for predicting the diameter of electrospun nanofibers. Based on the grey system theory, the effects of polyacrylonitrile mass fraction, voltage, flow rate, and receiving distance on fiber diameter were studied. The GM(1,1) (grey model) model and DNGM(1,1) (The DNGM (1,1) model is based on the whitening differential equation using parameters to Directly estimate the approximate Non-homogeneous sequence Grey prediction Model) model were established to predict fiber diameter by a single-factor change, and the results showed high prediction accuracy. The multi-variable grey model MGM(1,n) (MGM(1,n) is a Multivariate Grey prediction Model) was used for prediction of fiber diameter when multiple factors change simultaneously. The results showed that the average modeling fitting error is 8.62%. The background value coefficients of the MGM(1,n) model were optimized, the average modeling fitting error was reduced to 1.01%, and the average prediction error was reduced to 1.33%. Combining the fractional optimization with the background-value coefficient optimization, the optimal background-value coefficient α and the order r were selected. The results showed that the average modeling fitting error is 0.85%, and the average prediction error is 0.38%. The results demonstrate that the grey system theory can effectively predict the diameter of polyacrylonitrile electrospinning fibers with high prediction accuracy. This theory can increase the control of nanofiber diameters in production. [ABSTRACT FROM AUTHOR]

The three primary reactions in metal-air batteries and electrochemical hydrolysis are the hydrogen evolution reaction (HER), the oxygen evolution reaction (OER), and the oxygen reduction reaction (ORR). Therefore, it is crucial to develop efficient low-cost trifunctional catalysts. In this study, we design a self-supported electrocatalyst with hierarchical nanostructure, in which the bamboo-like nitrogen doped carbon nanotubes (NCNTs) encapsulated CoFe nanoparticles (CoFe NPs) in-situ anchored on nanoflower like CoFe 2 O 4 via chemical vapor deposition. Strikingly, the resulting catalysts CoFe@NC/CoFe 2 O 4 /IF demonstrate exciting trifunctional catalytic performance, overpotential of 66 mV and 185 mV for HER and OER at current densities of 10 mA cm−2, and a half-wave potential of 0.852 V for ORR, respectively. In addition, the maximum power density of the Zinc-air batteries (ZABs) assembled with CoFe@NC/CoFe 2 O 4 /IF as the cathode electrode is 134.5 mW cm−2; and the overall water splitting requires only a voltage of 1.50 V at a decomposition current density at 10 mA cm−2. This method provides a new strategy for trifunctional electrocatalysts and offers a promising approach for self-driven water electrolysis devices. • Self-supported electrocatalysts with multilevel nanostructures. • The catalyst exhibits remarkable HER, OER and ORR performance. • A variety of active species cooperatively enhance catalytic activity. • It can be applied to ZABs and self-driven overall water splitting. [ABSTRACT FROM AUTHOR]

Vortex spinning is a novel process for spinning short-staple yarns with high production rate and quality. The dynamics of the fiber in the nozzle plays a key role on the properties of the resultant yarn. In this paper, the images of fiber motion in the airflow inside the nozzle of vortex spinning are captured using a high-speed photography technique. The nozzle is magnified according to the Reynolds number similarity. Based on the high-speed photographic results, the effects of some parameters – the nozzle pressure, yarn delivery speed, and distance between the nozzle inlet and the hollow spindle – on the motional characteristics of the fiber are investigated. [ABSTRACT FROM PUBLISHER]

Abstract: China, an oil and NG scarcity country, is coal dependent, and this situation will remain for a long time. DME, as an ideal replacer of liquid fuel, is considered to develop. The efficient way of producing DME from coal is under research. Considering the components of coal and natural gas (NG), we choose co-feed (coal and NG) and co-production (electricity and DME) system (Co–Co system) to be studied on. Three systems which are the standalone system, co-generation system and Co–Co system are simulated by Aspen-Plus. The simulation results concerning material flows, exergy flows, CO2 emission and the evaluation indexes are obtained. It is found that Co–Co system has higher exergy efficiency, higher economic benefit, and it is environmental friendly because of releasing the least CO2.The analysis illustrates that Co–Co system has obviously advantage over the other two kinds of systems. [Copyright &y& Elsevier]

Abstract: The myelodysplasia/myeloid leukemia factor 1-interacting protein MLF1IP is a novel gene which encodes for a putative transcriptional repressor. It is localized to human chromosome 4q35.1 and is expressed in both the nuclei and cytoplasm of cells. Northern and Western blot analyses have revealed MLF1IP to be present at very low amounts in normal brain tissues, whereas a number of human and rat glioblastoma (GBM) cell lines demonstrated a high level expression of the MLF1IP protein. Immunohistochemical analysis of rat F98 and C6 GBM tumor models showed that MLF1IP was highly expressed in the tumor core where it was co-localized with MLF1 and nestin. Moreover, MLF1IP expression was elevated in the contralateral brain where no tumor cells were detected. These observations, together with previous data demonstrating a role for MLF1IP in erythroleukemias, suggest a possible function for this protein in glioma pathogenesis and potentially in other types of malignancies. [Copyright &y& Elsevier]