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We report herein the design of promising composite material as a cathode in a rechargeable battery by combining the properties of polypyrrole (PPy) and MnO2 particles. The composites were prepared by electropolymerization of the pyrrole monomer followed by electrodeposition of a manganese salt suspension by two methods. The first method involved the formation of MnO2 in situ in the PPy/ITO electrode, while the second method involved first a preliminary adsorption of Mn2+ ions in the polymer, followed by an electrochemical of the electrode. The morphology of the resulting composite materials (PPy/MnO2) was studied by energy-dispersive X-ray spectroscopy (EDS), X-ray diffractometry (XRD), scanning electron microscopy (SEM), Fourier-transform infrared (FTIR). The investigations of the electrochemical properties of the composite electrodes show that the presence of MnO2 play an important role in improving the surface of polymer films, which leads to lower charge transfer resistance and higher electrode activity. For the optimal synthesis method, the electrode generates a maximum current of up to − 7.9 mA cm−2 for the oxygen reduction reaction, which is eight times the current density delivered by the electrode without PPy. [ABSTRACT FROM AUTHOR]

In order to develop an innovative, environmentally friendly composite materials for the construction industry, this study aims to exploit three types of waste material to manufacture cement mortars for producing lightweight concretes, ecologically friendly paving slabs and pavers. For this purpose, the response surface methodology (RSM) was investigated to predict and optimize the physical properties of mortars made from dune sand (DS) combined with recycled sand (RS), which are abundant in the desert and considered as waste products, reinforced by polymerized polyethylene terephthalate (PET) fibers of two different lengths, 20 mm and 30 mm, respectively. This investigation was carried out to assess the material's capacity in terms of engineering criteria, including air content in the fresh state (Ac), shrinkage (Sh), flexural displacement (Yf), ultrasonic pulse velocity (UPV), and water absorption (WA). Further, the chemical composition and mineralogical transformations at high temperatures of the produced mortar were examined. The ANOVA analysis of variance and a desirability function (DF) test are developed based on the Box-Behnken Design to predict and optimize variables and output responses by maximizing the mechanical properties and minimizing the physical properties. The obtained results reveal a significant improvement in the physical properties of the mortars, 6.25% Sh, 43% Yf, 4.65% UPV, and 6.54% WA, confirming the beneficial effect of fiber-reinforced products compared with those without fibers. The proposed quadratic model proves the validity of the experimental results with a better accuracy of less than 4.5% error. The optimal formulation obtained in this protocol consisted of 50% DS, 50% RS, and 2% PET, with a length of 12.70 mm. This mix yielded 0.799% Ac, −95.28 μm/m Sh, 5.79 mm Yf, 3855.11 m/s UPV, and 11.91% WA, presenting an attractive option for applications in eco-construction sustainability. Therefore, The RSM model correlates well with the experimental data, which has contributed to an improvement in the physical-mechanical features. Consequently, this eco-mortar has several applications in buildings, roads, bridges, for bending elements (beams, slabs) and can also be used for repairing damaged structures. [Display omitted] • The RSM methodology has been used for the optimization and prediction process. • The three types of waste used DS-RS-PF have proven essential in eco-construction. • The 50/50 sand mixture is relevant for the high quality of the studied mortar. • DS-RS-PF combination decreases Ac, Sh, WA and increases Yf, UPV, showing high behavior. • Abandoned dune sand is considered to be waste. [ABSTRACT FROM AUTHOR]

• Economic valorisation of eco-mortar composed of dune sand, recycled sand and PET-F. • Dune sand corrected by recycled sand with PET-F improves the performance of the eco-mortar. • Dune sand and PET fibre-reinforced prisms enhance flexural strength. • The RSM responses optimally improve the physical–mechanical properties of eco-mortar. • The interaction of DS and RS provides a sustainable solution for eco-mortar production. Today, economic and environmental interests have become imperative in construction works. Therefore, the use of substitute materials for natural aggregates or cement contributes to the preservation of natural resources and the reduction of carbon dioxide diffusion. The large quantity of dune sand available in the Algerian Sahara and the affordable cost of recycled aggregates and plastic waste encourage their use as a replacement for natural aggregates in the production of cementitious materials. The interaction of dune sand (DS) and recycled sand (RS) with the introduction of a polyethylene terephthalate (PET-F) fibre help to design a normative ecological material. The aim of the study was to explore and optimize the proportions of these materials to create an environmentally-friendly cementitious product. The strategy is based on the progressive substitution of dune sand by another originating from demolition waste at different rates: 0%, 25%, 50%, 75% and 100%, and a gradual rate of PET-F fibres, 20 and 30 mm from 0% to 2% with a step of 0.5%. In this article, we study the effect of the new composites on the physico-mechanical performance of the designed eco-mortars through several tests (spreadability, fresh density, porosity, capillary and immersion absorption, compression strength, and flexural strength). In addition, we utilise Response Surface Methodology (RSM) to predict approximate parameters that influence the properties of new cementitious composites. The results obtained show the significant benefit of the following rates: 50% SD, 50% SR and (0.5%, 30 mm) PET-F fibre. Thus, the RSM model correlates well with the experimental data, which has undoubtedly led to an improvement in the physical–mechanical characteristics of the eco-mortar studied. Otherwise, the proposed model reaches a high pertinence, with a good desirability coefficient of 0.917. [ABSTRACT FROM AUTHOR]

This study presents the static and vibratory behavior of a hybrid sandwich plate with a magnetorheological elastomer core. In order to improve the static and vibrational behavior of the plate, the pseudo-fibers formed by the effect of the magnetic field on the elastomer charged by the ferromagnetic particles are oriented at 45° with respect to the direction of the magnetic field at 0°. Ritz's approach is taken to solve the physical problem. In order to verify and compare the results obtained by the Ritz approach, an analysis using the finite element method was carried out. The effect of the magnetic field on bending displacements, normal stresses, shear stresses, and static strain modes of the off-axis anisotropic hybrid sandwich plate are discussed. The rheological property of the MRE material at 0° and at 45° are determined experimentally, and are exploited in the two numerical approaches. The natural frequencies and the modal damping of the sandwich plate are calculated and discussed for various magnetic field intensities. The results obtained by the two methods are compared. These off-axis anisotropic MRE structures could open up new opportunities in various fields of aeronautics, aerospace, mechanical engineering and civil engineering. [ABSTRACT FROM AUTHOR]

Background and Objectives: By convention, patients who have undergone a craniotomy for tumor are monitored in a neurocritical care unit (NCCU) overnight, yet there is little evidence to justify the need for such intense care. Here, we compared postoperative adverse events in patients after brain tumor surgeries surveilled in a NCCU overnight or postanesthesia care unit (PACU) for a shorter duration., Methods: We retrospectively studied 1070 consecutive patients who underwent craniotomy for brain tumor between 2016 and 2021. Inclusion criteria were age ≥18 years and craniotomy for resection or biopsy of intracerebral or extracerebral tumors. Cohorts were divided into 2 groups based on recovery destination, NCCU or PACU. Medical history, preoperative and postoperative neuroimaging, surgical resection features, diagnosis, and postoperative adverse events within 24 hours were reviewed for all patients., Results: A total of 674 patients in the NCCU group and 396 patients in the PACU group were studied. The mean ages were 55.7 (NCCU) and 59.6 (PACU) years ( P < .001). The American Society of Anesthesiologists class was not significantly different between groups ( P = .42). The median recovery time was 19 hours (SD 24.5) for the NCCU group and 4 hours (SD 8) for the PACU group ( P < .001). The incidence of adverse events within 24 hours postsurgery was 0.04 for the NCCU group and 0.028 for the PACU group (odds ratio 0.69, 95% CI 0.32-1.38, P = .40). The mean postoperative hospital stay was 9.6 days (SD 15.6) for the NCCU group and 8.5 days (SD 17.5) for the PACU group ( P < .001)., Conclusion: The incidence of adverse events within 24 hours after brain tumor surgery was not different between patients being surveilled for a long period in a NCCU or for a short period in a PACU., Competing Interests: The authors have no personal, financial, or institutional interest in any of the drugs, materials, or devices described in this article., (© The Author(s) 2025. Published by Wolters Kluwer Health, Inc. on behalf of Congress of Neurological Surgeons.)

The existence of neural stem cells (NSCs) in adult human brain neurogenic regions remains unresolved. To address this, we created a cell atlas of the adult human subventricular zone (SVZ) derived from fresh neurosurgical samples using single-cell transcriptomics. We discovered 2 adult radial glia (RG)-like populations, aRG1 and aRG2. aRG1 shared features with fetal early RG (eRG) and aRG2 were transcriptomically similar to fetal outer RG (oRG). We also captured early neuronal and oligodendrocytic NSC states. We found that the biological programs driven by their transcriptomes support their roles as early lineage NSCs. Finally, we show that these NSCs have the potential to transition between states and along lineage trajectories. These data reveal that multipotent NSCs reside in the adult human SVZ., Competing Interests: The authors declare no competing interests., (© 2024 The Author(s).)

Antigen-specific T cell expansion ex vivo followed by adoptive transfer enables targeting of a multitude of microbial and cancer antigens. However, clinical-scale T cell expansion from rare precursors requires repeated stimulation, which may lead to T cell dysfunction and limited therapeutic potential. We used a clinically compliant protocol to expand Epstein-Barr virus (EBV) and Wilms tumor 1 (WT1) antigen-specific CD8 + T cells, and leveraged T cell exhaustion-associated inhibitory receptor blockade to improve T cell expansion. Several inhibitory receptors were expressed early by ex vivo -expanded antigen-specific CD8 + T cells, including PD-1 and TIM3, with co-expression matching evidence of T cell dysfunction as the cultures progressed. Introduction of anti-PD-L1 and anti-TIM3 blockade in combination (but not individually) to the culture led to markedly improved antigen-specific T cell expansion without inducing T cell dysfunction. Single-cell RNA sequencing (RNA-seq) and T cell receptor (TCR) repertoire profiling revealed that double blockade does not impart specific transcriptional programs in T cells or alterations in TCR repertoires. However, combined blockade may affect gene expression in a minority of clonotypes in a donor-specific fashion. We conclude that antigen-specific CD8 + T cell manufacturing can be improved by using TIM3 and PD-L1/PD-1 axis blockade in combination. This approach is readily applicable to several adoptive immunotherapy strategies., Competing Interests: The authors declare no competing interests., (© 2022 The Author(s).)