Abstract

Ischemic stroke (IS) is a neurological condition characterized by severe long-term consequences and an unfavorable prognosis for numerous patients. Despite advancements in stroke treatment, existing therapeutic approaches possess certain limitations. However, accumulating evidence suggests that mesenchymal stem/stromal cells (MSCs) hold promise as a potential therapy for various neurological disorders, including IS, owing to their advantageous properties, such as immunomodulation and tissue regeneration. Additionally, MSCs primarily exert their therapeutic effects through the release of extracellular vesicles (EVs), highlighting the significance of their paracrine activities. These EVs are small double-layered phospholipid membrane vesicles, carrying a diverse cargo of proteins, lipids, and miRNAs that enable effective cell-to-cell communication. Notably, EVs have emerged as attractive substitutes for stem cell therapy due to their reduced immunogenicity, lower tumorigenic potential, and ease of administration and handling. Hence, this review summarizes the current preclinical and clinical studies performed to investigate the safety and therapeutic potential of MSCs and their EVs derived from different sources, including bone marrow, adipose tissue, umbilical cord blood, and Wharton’s jelly in IS.

Abstract

As industries continue to release pollutants into the environment, the preservation of the environment has become a crucial concern. Among these pollutants, dye pollutants are particularly dangerous because they degrade slowly and pose a threat to aquatic life. In this paper, the removal and degradation of two dangerous dye contaminants, Malachite Green (MG) and Congo red (CR), by gC3N4 and its composites and derivatives, were investigated. The results have shown that these composites have effectively removed both CR and MG dye contaminants from aqueous media in almost all studies, with a high degradation rate of over 90%. Also, in all studies, composites and derivatives of g-C3N4 have been found to destroy these two dye pollutants more effectively than g-C3N4 alone. Finally, as a general outcome, g-C3N4 and its composites can be utilized on a large scale in the textile industry to eliminate dye contaminants and aid in preserving the environment for future generations.

Abstract

A complex sequence of occurrences, including host genetic vulnerability, Helicobacter pylori infection, and other environmental variables, culminate in gastric cancer (GC). The development of several genetic and epigenetic changes in oncogenes and tumor suppressor genes causes dysregulation of several signaling pathways, which upsets the cell cycle and the equilibrium between cell division and apoptosis, leading to GC. Developments in computational biology and RNA-seq technology enable quick detection and characterization of long non-coding RNAs (lncRNAs). Recent studies have shown that long non-coding RNAs (lncRNAs) have multiple roles in the development of gastric cancer. These lncRNAs interact with molecules of protein, RNA, DNA, and/or combinations. This review article explores several gastric cancer-associated lncRNAs, such as ADAMTS9-AS2, UCA1, XBP-1, and LINC00152. These various lncRNAs could change GC cell apoptosis, migration, and invasion features in the tumor microenvironment. This review provides an overview of the most recent research on lncRNAs and GC cell apoptosis, migration, invasion, and drug resistance, focusing on studies conducted in cancer cells and healthy cells during differentiation.

Abstract

In this study, hydroxyapatite (HA) was used as a bioceramic on a TiNi shape memory alloy. Butanol and tri-ethanolamine were used as suspensions with HA particles. The electrophoretic deposition (EPD) process was performed at 20, 30, and 40 V for 1–5 min on the cathode. Samples were left at room temperature for 24 hours to obtain slow drying after deposition. Weight and layer thickness were then measured. Sintering was conducted in an Ar atmosphere at 800°C for 2 h. The phases and surface morphologies were examined using XRD and SEM. The results showed that a uniform, homogeneous, crack-free coating layer can be achieved at a voltage of 30 V and low sintering temperatures. Also, longer deposition times increased the coatings' weight and thickness. Compared to other deposition methods, such as sol-gel and plasma coating, the method presented in this research can be used as an alternative method for bioactive coatings. The hardness of the undecorated HA coatings obtained at 15 and 30 V EPD voltage reached 0.2245 ± 0.036 GPa and 0.0661 ± 0.008 GPa, respectively.

Filters are essential tools in the field of signal processing, they have been employed to control the signals and reduce or eliminate the noise associated with the signal. In this article, we will show the importance of filters in signal processing, especially in the field of biomedical engineering. As these filters will be applied to filter and remove noise from the electrocardiogram (ECG) signal, we will learn about some of the filters in this article.

Abstract

Constructing a sulfur-vacancy-enriched heterostructure offers advantages in enhancing photocatalytic performance due to the synergy between the vacancy’s electron-trapping and the internal electric field (IEF) features. In this study, a series of IEF-modulated type-I heterostructures containing sulfur vacancies-rich ZnIn2S4 (SV-ZIS) and Bi2Se3 (BSe) was rationally developed by hydrothermal and reduction methods. The optimized BSe@SV-ZIS catalyst shows an outstanding photocatalytic Cr(VI) reduction and tetracycline degradation rates, which are ∼ 2.1 and ∼ 1.5 times higher than that of pure SV-ZIS and BSe, respectively. Notably, the enhanced catalytic performance of binary samples could be linked to efficient absorption of the full spectrum of light, heterojunction formation and larger contact area to enhance the charge carriers movement at their interface and exceptional photo-stability. By assisting DRS, VB-XPS, and UPS analyses, details of the energy band position, charge carriers transport route, and preliminary photocatalytic mechanism were systematically explored. Furthermore, radical scavenging and electron paramagnetic resonance experiments were conducted to provide evidence of the participation of the reactive species during photocatalysis over BSe@SV-ZIS. Kinetic analysis revealed that the rate of photocatalytic process adheres to the Langmuir–Hinshelwood kinetic model. These results demonstrated that the heterostructuring approach holds significant potential as an effective avenue for developing photocatalysts that can harness both visible and NIR light, offering promising solutions to contemporary challenges in the realms of environmental decontamination and energy.

Abstract

The weak spots have been examined, a solution has been suggested, the solution has been applied, and a comparison between the simulation and experimental test results has been given in this work. In order to do this, a nonlinear model predictive controller and a linear quadratic regulator controller have been utilized to control a four-wheel mobile robot during modeling and implementation. But the combination of these classic and modern controllers with machine learning can greatly help to make these controllers work more accurately; As a result, in order to increase the accuracy of the performance of these controllers, by training neural networks of multilayer perceptrons, the controllers have been made intelligent. Controllers with cost function have coefficients as weighting to the matrix of system state variables and control input, which are greatly affected by changing these two weighting matrices of problem solving and optimization. For this reason, it is necessary to extract these two matrices for each separate path in order to improve the performance of the controller by trial and error. But by applying the proposed network which is trained with a new algorithm, not only the performance accuracy has increased, but the network extracts these two matrices without the need to spend human energy. Additionally, by training additional neural networks to optimally extract the benefit of the forecast horizon, fewer calculations and faster solution times have been achieved, helping to reduce the current time delays, particularly in the implementation of the nonlinear controller on the robot in the experimental mode. In the hardware section, the solution time has been shortened by looking at and utilizing operators like the U2D2 interface and the pixy camera, which are quicker than the standard procedure. The information indicates that the proposed intelligence technology reacts 40%–50% quicker than the NMPC standard procedure. The suggested algorithm has also minimized the path tracking error since it extracts the optimal gain at each stage. Moreover, a hardware mode solving speed comparison between the recommended and conventional methods is given. In this domain, a 33% increase in solving speed has been noted.

Abstract

In this research, we introduced a novel counter electrode (CE) for dye-sensitized solar cells (DSSCs) based on crystalline WSe2 doped with Zn impurities. The crystalline nature of these CEs was confirmed through X-ray diffraction (XRD) analysis. Additionally, we demonstrated that Zn dopants significantly enhances the electrochemical and electrocatalytic properties of the CEs. These improvements were verified using electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV), and Tafel analysis with iodine-based electrolytes. Collectively, these enhancements resulted in a remarkable 42 % increase in DSSC efficiency, improving it from 5.78 % to 8.19 % under optimized conditions. Notably, this surpassed the performance of platinum-based CEs, which achieved 7.66 % efficiency. The proposed CE holds great promise for advancing DSSCs by elevating their efficiency and reducing fabrication costs.

Abstract

This study aims to optimize the economic thermodynamics of a flat plate solar collector and investigate transient heat transfer. This study focuses on modeling and optimization under unfavorable radiation conditions. The method employed here is optimization using a multi-objective genetic algorithm with the assistance of MATLAB software. The key components include objective functions, constraints, and design variables, which are the collector efficiency and the annual total price. The results indicate that increasing the length of the collector has a negative impact on the thermodynamic efficiency and increases the total annual price. Conversely, increasing the width of the collector initially improves the thermodynamic efficiency but then decreases it while also increasing the total annual price. Furthermore, increasing the number of pipes leads to a decrease in the total annual price and an initial increase followed by a decrease in the thermodynamic efficiency. The research was conducted over four different days.

Abstract

A radial flux permanent magnet generator can be effectively used in generating wind power at low speeds. This generator uses a combination of permanent magnets and a stator to produce electricity from the wind’s kinetic energy. The permanent magnets are arranged in a radial pattern, which reduces the amount of heat lost and therefore increases the generator’s efficiency. This design allows for a low rotational speed, which makes it suitable for applications such as wind turbines. The air gap between the rotor and the stator affects the output voltage and power due to the decrease in magnetic flux. This study aims to increase the generator’s output voltage and output power by fitting stator teeth widths to the stator teeth. The stator teeth width fitting design method adjusts the air gap between the stator and the rotor to a uniform size. This helps to reduce the pulsating torque and ensure that the output voltage and power are maximized. The three variables are the stator slot width, the rotor slot width, and the air gap width. By adjusting these variables, the stator teeth width fitting design method can adjust the air gap between the stator and rotor.

Abstract

Background

Aluminum phosphide (AlP) is a well-known toxic compound used as an agricultural pesticide to prevent insect damage to stored crops. However, even if just a small amount was consumed, it caused lasting harm to the human body and, in acute concentrations, death. The current study employed cerium oxide nanoparticles (CeO2 NPs) to reduce oxidative stress and various harmful outcomes of AlP poisoning.

Methods

Following finding effective concentrations of CeO2 NPs via MTT assay, Human Cardiac Myocyte (HCM) cells were pre-treated with CeO2 NPs for 24 h. After that, they were exposed to 2.36 μM AlP. The activity of oxidative stress and mitochondrial biomarkers, including mitochondrial swelling, mitochondrial membrane potential, and cytochrome c release, were evaluated in HCM cells. Finally, the population of apoptotic and necrotic cells was assessed via flow cytometry.

Results

After 24 h, data revealed that all tested concentrations of CeO2 NPs were safe, and 25 and 50 μM of that were selected as effective concentrations. Oxidative stress markers (malondialdehyde, protein carbonyl, superoxide dismutase, and catalase) showed that CeO2 NPs could successfully decrease AlP poisoning due to their antioxidant characteristics. Mitochondrial markers were also recovered by pre-treatment of HCM cells with CeO2 NPs. Furthermore, pre-treating with CeO2 NPs could compensate for the reduction of live cells with AlP and cause a diminishing in the population of early and late apoptotic cells.

Conclusion

As a result, it is evident that CeO2 NPs, through the recovery of oxidative stress and mitochondrial damages caused by AlP, reduce apoptosis and have therapeutic potentials on HCM cells.

Graphical abstract

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Abstract

The optomechanically induced grating (OMIG) in a nanocavity using a bilayer graphene system as the intracavity medium has been proposed. We investigate the effects of different parameters on the Fraunhofer diffraction pattern of the incident probe light. Here, one mirror of the nanocavity is considered coherently driven by the standing wave coupling and probe fields, whereas the second mirror has mechanical oscillation due to the radiation pressure. We consider interaction of bilayer graphene with the optomechanical cavity and show that OMIG can be obtained corresponding to output probe field frequency. Moreover, we find that under specific parametric conditions, most of the probe energy can transfer to the higher orders of the diffraction and only a small portion remains in the zero order.

Abstract

Insufficient synchronization between the operational efficiency of capacitors and tap-changer transformers in regulating voltage presents a fundamental challenge in distribution networks, which in turn hinders the control performance. This challenge is caused by the inability of these two components to synchronize their respective operations properly. In this study, a novel control strategy is presented with the objective of achieving synchronization in the functioning of capacitors and tap transformers. Depending on the load change, various devices can be used to control the distribution network voltage. On Load Tap Changers (OLTCs) and Capacitor Banks (CBs) respond slowly to voltage changes. If the voltage changes rapidly, such devices are useless and should be avoided. Keying may shorten lifespan. This study investigated a new optimal control mechanism for coordinating tap transformers and capacitors. The optimization of tap trans- and capacitor-stage operation through the use of a Genetic Algorithm (GA) results in the reduction of superfluous switching. The limits for Point of Common Coupling (PCC) bus voltage and power factor are 0.94 and 1.02 per unit, respectively. The secondary control stage regulates the voltage of the feeder bus within the range of 0.95 to 1.05 per unit. Following the second-stage regulation of the terminal buses in the N network feeder, the third stage governs the PCC bus voltage. To prevent an infinite control loop, the voltage of the PCC bus is regulated within the range of 0.95 to 1.05 per unit (PU). These findings indicate that the optimization model is capable of achieving maximum efficiency in controlling the voltage of the distribution network. In the interim, this optimization technique produces outcomes of greater accuracy, as evidenced by a voltage value that remains consistently close to unity [Root Mean Square Error (RMSE) = 0.85] across a broad spectrum of network-loading scenarios.

Abstract

In this study, magnetic CoFe2O4 nanoparticles (CFO NPs) were fabricated by coprecipitation method for the removal of crystal violet (CV), Cu(II) and Cd(II) from environmental water samples in batch mode. This study investigated the effect of CFO NPs on the removal of CV, Cu(II), and Cd(II) using the response surface methodology (RSM) based on central composite design (CCD). For this purpose, batch experiments were designed and performed to evaluate the effect of variables such as pH, adsorbent amount, sonication time, and concentration of pollutants using RSM. Under optimal conditions (ultrasound time of 17 min, pollutant concentration of 15 mg L−1, CFO NPs amount of 0.24 g, and pH = 6), the removal efficiency was achieved in the range of 95.86–99.82%. Evaluating the reusability of the CFO NPs showed that the CFO NPs adsorbent can be reused for up to 5 cycles while maintaining its high efficiency in removing CV, Cu(II) and Cd(II). The removal efficiency of CV, Cu(II) and Cd(II) was obtained in the range of 91.68–97.59% for real samples. Overall, the results revealed that CFO NPs adsorbent has a high ability to remove CV, Cu(II) and Cd(II) from different water samples.

Abstract

In recent years, bimetallic strips have been progressively used in manufacturing to make collective purposes. Amongst cladding approaches, the rolling process is one of the most popular processes in making bimetallic strips. In this study, a new analytical model based on the slab method has been proposed to predict the bond strength of two layer strips. Results show that the bond strength of strips increases with increasing total rolling thickness reduction of the samples. Also, the finite element simulation and an experimental study were run to approve the results obtained from the new analytical model for producing AA1060/AA7075 bimetallic strips. Moreover, the planned analytical model is appropriate for modeling the roll bonding process of the two-layer strips and it is proficient to extend our information in engineering and production of bimetal strips. The bonding strength of bilayer samples enhanced by increasing the reduction in thickness ratio. The peeled surface of samples has been investigated using scanning electron microscopy (SEM).